第一篇：超聲波測(cè)距畢業(yè)論文中英文對(duì)照資料外文翻譯文獻(xiàn)

超聲波測(cè)距畢業(yè)論文中英文對(duì)照資料外文翻譯文獻(xiàn)

超聲波測(cè)距 中英文對(duì)照資料外文翻譯 超聲測(cè)距系統(tǒng)設(shè)計(jì) 原文出處：傳感器文摘 布拉福德:1993年 第13頁(yè)摘要：超聲測(cè)距技術(shù)在工業(yè)現(xiàn)場(chǎng)、車輛導(dǎo)航、水聲工程等領(lǐng)域都具有廣泛的應(yīng)用價(jià)值，目前已應(yīng)用于物位測(cè)量、機(jī)器人自動(dòng)導(dǎo)航以及空氣中與水下的目標(biāo)探測(cè)、識(shí)別、定位等場(chǎng)合。因此，深入研究超聲的測(cè)距理論和方法具有重要的實(shí)踐意義。為了進(jìn)一步提高測(cè)距的精確度，滿足工程人員對(duì)測(cè)量精度、測(cè)距量程和測(cè)距儀使用的要求，本文研制了一套基于單片機(jī)的便攜式超聲測(cè)距系統(tǒng)。關(guān)鍵詞：超聲波，測(cè)距儀，單片機(jī)

1、前言 隨著科技的發(fā)展，人們生活水平的提高，城市發(fā)展建設(shè)加快，城市給排水系統(tǒng)也有較大發(fā)展，其狀況不斷改善。但是，由于歷史原因合成時(shí)間住的許多不可預(yù)見因素，城市給排水系統(tǒng)，特別是排水系統(tǒng)往往落后于城市建設(shè)。因此，經(jīng)常出現(xiàn)開挖已經(jīng)建設(shè)好的建筑設(shè)施來改造排水系統(tǒng)的現(xiàn)象。城市污水給人們帶來了困擾，因此箱涵的排污疏通對(duì)大城市給排水系統(tǒng)污水處理，人們生活舒適顯得非常重要。而設(shè)計(jì)研制箱涵排水疏通移動(dòng)機(jī)器人的自動(dòng)控制系統(tǒng)，保證機(jī)器人在箱涵中自由排污疏通，是箱涵排污疏通機(jī)器人的設(shè)計(jì)研制的核心部分。控制系統(tǒng)核心部分就是超聲波測(cè)距儀的研制。因此，設(shè)計(jì)好的超聲波測(cè)距儀就顯得非常重要了。

2、超聲波測(cè)距原理2.1 壓電式超聲波發(fā)生器原理 畢業(yè)設(shè)計(jì)（論文）英文翻譯 壓電式超聲波發(fā)生器實(shí)際上是利用壓電晶體的諧振來工作的。超聲波發(fā)生器內(nèi)部結(jié)構(gòu)，它有兩個(gè)壓電晶片和一個(gè)共振板。當(dāng)它的兩極外加脈沖信號(hào)，其頻率等于壓電晶片的固有振蕩頻率時(shí)，壓電晶片將會(huì)發(fā)生共振，并帶動(dòng)共振板振動(dòng)，便產(chǎn)生超聲波。反之，如果兩電極間未外加電壓，當(dāng)共振板接收到超聲波 時(shí)，將壓迫壓電晶片作振動(dòng)，將機(jī)械能轉(zhuǎn)換為電信號(hào)，這時(shí)它就成為超聲波接收器了。測(cè)量脈沖到達(dá)時(shí)間的傳統(tǒng)方法是以擁有固定參數(shù)的接收信號(hào)開端為基礎(chǔ)的。這個(gè)界限恰恰選于噪音水平之上，然而脈沖到達(dá)時(shí)間被定義為脈沖信號(hào)剛好超過界限的第一時(shí)刻。一個(gè)物體的脈沖強(qiáng)度很大程度上取決于這個(gè)物體的自然屬性尺寸還有它與傳感器的距離。進(jìn)一步說，從脈沖起始點(diǎn)到剛好超過界限之間的時(shí)間段隨著脈沖的強(qiáng)度而改變。結(jié)果，一種錯(cuò)誤便出現(xiàn)了——兩個(gè)擁有不同強(qiáng)度的脈沖在不同時(shí)間超過界限卻在同一時(shí)間到達(dá)。強(qiáng)度較強(qiáng)的脈沖會(huì)比強(qiáng)度較弱的脈沖超過界限的時(shí)間早點(diǎn)，因此我們會(huì)認(rèn)為強(qiáng)度較強(qiáng)的脈沖屬于較近的物體。2.2 超聲波測(cè)距原理 超聲波發(fā)射器向某一方向發(fā)射超聲波，在發(fā)射時(shí)刻的同時(shí)開始計(jì)時(shí)，超聲波在空氣中傳播，途中碰到障礙物就立即返回來，超聲波接收器收到反射波就立即停止計(jì)時(shí)。超聲波在空氣中的傳播速度為 340m/s，根據(jù)計(jì)時(shí)器記錄的時(shí)間 t，就可以計(jì)算出發(fā)射點(diǎn)距障礙物的距離s，即：s340t/

23、超聲波測(cè)距系統(tǒng)的電路設(shè)計(jì) 系統(tǒng)的特點(diǎn)是利用單片機(jī)控制超聲波的發(fā)射和對(duì)超聲波自發(fā)射至接收往返時(shí)間的計(jì)時(shí)，單片機(jī)選用 C51，經(jīng)濟(jì)易用，且片內(nèi)有 4K 的 ROM，便于編程。電路原理圖如圖 1 所示。‐1‐畢業(yè)設(shè)計(jì)（論文）英文翻譯 圖 1 電路原理圖 ‐2‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯3.1 40kHz 脈沖的產(chǎn)生與超聲波發(fā)射 測(cè)距系統(tǒng)中的超聲波傳感器采用 UCM40 的壓電陶瓷傳感器，它的工作電壓是40kHz 的脈沖信號(hào)，這由單片機(jī)執(zhí)行下面程序來產(chǎn)生。puzel： mov 14h 12h；超聲波發(fā)射持續(xù) 200mshere： cpl p1.0 ； 輸出 40kHz 方波 nop ； nop ； nop ； djnz 14h，here； ret 前方測(cè)距電路的輸入端接單片機(jī) P1.0 端口，單片機(jī)執(zhí)行上面的程序后，在 P1.0端口輸出一個(gè) 40kHz 的脈沖信號(hào)，經(jīng)過三極管 T 放大，驅(qū)動(dòng)超聲波發(fā)射頭 UCM40T，發(fā)出 40kHz 的脈沖超聲波，且持續(xù)發(fā)射 200ms。右側(cè)和左側(cè)測(cè) 距電路的輸入端分別接 P1.1 和 P1.2 端口，工作原理與前方測(cè)距電路相同。3.2 超聲波的接收與處理 接收頭采用與發(fā)射頭配對(duì)的 UCM40R，將超聲波調(diào)制脈沖變?yōu)榻蛔冸妷盒盘?hào)，經(jīng) IC2運(yùn)算放大器 IC1A 和 IC1B 兩極放大后加至 IC2。是帶有鎖 定環(huán)的音頻譯碼集成塊LM567，內(nèi)部的壓控振蕩器的中心頻率 f01/1.1R8C3，電容 C4 決定其鎖定帶寬。調(diào)節(jié) R8 在發(fā)射的載頻上，則 LM567 輸入信號(hào)大于 25mV，輸出端 8 腳由高電平躍變?yōu)榈碗娖剑鳛橹袛嗾?qǐng)求信號(hào)，送至單片機(jī)處理.前方測(cè)距電路的輸出端接單片機(jī) INT0 端口，中斷優(yōu)先級(jí)最高，左、右測(cè)距電路的輸出通過與門 IC3A 的輸出接單片機(jī) INT1 端口，同時(shí)單片機(jī) P1.3 和 P1.4 接到 IC3A的輸入端，中斷源的識(shí)別由程序查詢來處理，中斷優(yōu)先級(jí)為先右后左。部分源程序如下：receive1：push psw push acc clr ex1； 關(guān)外部中斷 1 jnb p1.1right；P1.1 引腳為 0轉(zhuǎn)至右測(cè)距電路中斷服務(wù)程序 ‐3‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯 jnb p1.2left；P1.2 引腳為 0轉(zhuǎn)至左測(cè)距電路中斷服務(wù)程序return： SETB EX1； 開外部中斷 1 pop acc pop psw retiright：...； 右測(cè)距電路中斷服務(wù)程序入口 ajmp returnleft：...； 左測(cè)距電路中斷服務(wù)程序入口 ajmp return3.3 計(jì)算超聲波傳播時(shí)間 在啟動(dòng)發(fā)射電路的同時(shí)啟動(dòng)單片機(jī)內(nèi)部的定時(shí)器 T0，利用定時(shí)器的計(jì)數(shù)功能記錄超聲波發(fā)射的時(shí)間和收到反射波的時(shí)間。當(dāng)收到超聲波反射波時(shí)，接收電路 輸出端產(chǎn)生一個(gè)負(fù)跳變，在 INT0 或 INT1 端產(chǎn)生一個(gè)中斷請(qǐng)求信號(hào)，單片機(jī)響應(yīng)外部中斷請(qǐng)求，執(zhí)行外部中斷服務(wù)子程序，讀取時(shí)間差，計(jì)算距離。其部分源程序如下：RECEIVE0： PUSH PSW PUSH ACC CLR EX0 ； 關(guān)外部中斷 0 MOV R7 TH0 ； 讀取時(shí)間值 MOV R6 TL0 CLR C MOV A R6 SUBB A 0BBH； 計(jì)算時(shí)間差 MOV 31H A ； 存儲(chǔ)結(jié)果 MOV A R7 SUBB A 3CH MOV 30H A SETB EX0 ； 開外部中斷 0 POP ACC ‐4‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯 POP PSW RETI對(duì)于一個(gè)平坦的目標(biāo)，距離測(cè)量包括兩個(gè)階段:粗糙的測(cè)量和精細(xì)測(cè)量。第一步：脈沖的傳送產(chǎn)生一種簡(jiǎn)單的超聲波。第二步：根據(jù)公式改變回波放大器的獲得量直到回?fù)鼙粰z測(cè)到。第三步：檢測(cè)兩種回波的振幅與過零時(shí)間。第四步：設(shè)置回波放大器的所得來規(guī)格輸出，假定是 3 伏。通過脈沖的周期設(shè)置下一 個(gè)脈沖。根據(jù)第二部的數(shù)據(jù)設(shè)定時(shí)間窗。第五步：發(fā)射兩串脈沖產(chǎn)生干擾波。測(cè)量過零時(shí)間與回波的振幅。如果逆向發(fā)生在回 波中，決定要不通過在低氣壓插入振幅。第六步：通過公式計(jì)算距離 y。

4、超聲波測(cè)距系統(tǒng)的軟件設(shè)計(jì) 軟件分為兩部分，主程序和中斷服務(wù)程序。主程序完成初始化工作、各路超聲波發(fā)射和接收順序的控制。定時(shí)中斷服務(wù)子程序完成三方向超聲波的輪流發(fā)射，外部中斷服務(wù)子程序主要完成時(shí)間值的讀取、距離計(jì)算、結(jié)果的輸出等工作。

5、結(jié)論 對(duì)所要求測(cè)量范圍 30cm200cm 內(nèi)的平面物體做了多次測(cè)量發(fā)現(xiàn)，其最大誤差為0.5cm，且重復(fù)性好?？梢娀趩纹瑱C(jī)設(shè)計(jì)的超聲波測(cè)距系統(tǒng)具有硬件結(jié)構(gòu)簡(jiǎn)單、工作可靠、測(cè)量誤差小等特點(diǎn)。因此，它不僅可用于移動(dòng)機(jī)器人，還可用在其它檢測(cè)系統(tǒng)中。思考：至于為什么接收不用晶體管做放大電路呢，因?yàn)榉糯蟊稊?shù)搞不好，集成放大電路，還帶自動(dòng)電平增益控制，放大倍數(shù)為 76dB，中心頻率是 38k 到 40k，剛好是超聲波傳感器的諧振頻率。‐5‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯 參考文獻(xiàn)1.Fox J.D.Khuri-Yakub B.T.and Kino G.S.quotHigh Frequency Acoustic WaveMeasurement in Airquot in Proceedings of IEEE 1983 Ultrasonic Symposium October 31-2November 1983 Atlanta GA pp.581-4.2.Martin Abreu J.M.Ceres R.and Freire T.quotUltrasonic Ranging: Envelope AnalysisGives Improved Accuracyquot Sensor Review Vol.12 No.1 1992 pp.17-21.3.Parrilla M.Anaya J.J.and Fritsch C.quotDigital Signal Processing Techniques for HighAccuracy Ultrasonic Range Measurementsquot IEEE Transactions: Instrumentation andMeasurement Vol.40 No.4 August 1991 pp.759-63.4.Canali C.Cicco G.D.Mortem B.Prudenziati M.and Taron A.quotA TemperatureCompensated Ultrasonic Sensor Operating in Air for Distance and ProximityMeasurementquot IEEE Transaction on Industry Electronics Vol.IE-29 No.4 1982 pp.336-41.‐6‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯 Ultrasonic ranging system design Publicationtitle: Sensor Review.Bradford: 1993.Vol.13ABSTRACT：Ultrasonic ranging technology has wide using worth in many fields，such as the industriallocale，vehicle navigation and sonar engineering．Now it has been used in level measurement，self-guided autonomous vehicles fieldwork robots automotive navigation，air and underwater targetdetection，identification，location and so on．So there is an important practicing meaning to learn theranging theory and ways deeply.To improve the precision of the ultrasonic ranging system in hand，satisfy the request of the engineering personnel for the ranging precision，the bound and the usage，aportable ultrasonic ranging system based on the single chip processor was developed．Keywords：Ultrasound r，Ranging System，Single Chip Processor1.Introductive With the development of science and technology the improvement of peoplesstandard of living speeding up the development and construction of the city.urbandrainage system have greatly developed their situation is constantly improving.Howeverdue to historical reasons many unpredictable factors in the synthesis of her time the citydrainage system.In particular drainage system often lags behind urban construction.Therefore there are often good building excavation has been building facilities to upgradethe drainage system phenomenon.It brought to the city sewage and it is clear to the citysewage and drainage culvert in the sewage treatment system.comfort is very important topeoples lives.Mobile robots designed to clear the drainage culvert and the automaticcontrol system Free sewage culvert clear guarantee robot the robot is designed to clear theculvert sewage to the core.Control System is the core component of the development ofultrasonic range finder.Therefore it is very important to design a good ultrasonic rangefinder.2.A principle of ultrasonic distance measurement ‐7‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯2.1 The principle of piezoelectric ultrasonic generator Piezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work.Ultrasonic generator the internal structure as shown it has two piezoelectric chip and aresonance plate.When its two plus pulse signal the frequency equal to the intrinsicpiezoelectric oscillation frequency chip the chip will happen piezoelectric resonance andpromote the development of plate vibration resonance ultrasound is generated.Converselyif the two are not inter-electrode voltage when the board received ultrasonic resonance itwill be for vibration suppression of piezoelectric chip the mechanical energy is convertedto electrical signals then it becomes the ultrasonic receiver.The traditional way to determine the moment of the echos arrival is based onthresholding the received signal with a fixed reference.The threshold is chosen well abovethe noise level whereas the moment of arrival of an echo is defined as the first moment theecho signal surpasses that threshold.The intensity of an echo reflecting from an objectstrongly depends on the objects nature size and distance from the sensor.Further the timeinterval from the echos starting point to the moment when it surpasses the thresholdchanges with the intensity of the echo.As a consequence a considerable error may occurEven two echoes with different intensities arriving exactly at the same time will surpass thethreshold at different moments.The stronger one will surpass the threshold earlier than theweaker so it will be considered as belonging to a nearer object.2.2The principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound in the moment to launch thebeginning of time at the same time the spread of ultrasound in the air obstacles on his wayto return immediately the ultrasonic reflected wave received by the receiver immediatelystop the clock.Ultrasound in the air as the propagation velocity of 340m / s according tothe timer records the time t we can calculate the distance between the launch distancebarrier s that is: s 340t / 23.Ultrasonic Ranging System for the Second Circuit Design ‐8‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯 System is characterized by single-chip microcomputer to control the use of ultrasonictransmitter and ultrasonic receiver since the launch from time to time single-chip selectionof 8751 economic-to-use and the chip has 4K of ROM to facilitate programming.Circuitschematic diagram shown in Figure 2.Figure 1 circuit principle diagram ‐9‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯3.1 40 kHz ultrasonic pulse generated with the launch Ranging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40its operating voltage of the pulse signal is 40kHz which by the single-chip implementationof the following procedures to generate.puzel: mov 14h 12h ultrasonic firing continued 200mshere: cpl p1.0 output 40kHz square wave nop nop nop djnz 14h here ret Ranging in front of single-chip termination circuit P1.0 input port single chipimplementation of the above procedure the P1.0 port in a 40kHz pulse output signal afteramplification transistor T the drive to launch the first ultrasonic UCM40T issued 40kHzultrasonic pulse and the continued launch of 200ms.Ranging the right and the left side ofthe circuit respectively then input port P1.1 and P1.2 the working principle and circuit infront of the same location.3.2 Reception and processing of ultrasonic Used to receive the first launch of the first pair UCM40R the ultrasonic pulsemodulation signal into an alternating voltage the op-amp amplification IC1A and afterpolarization IC1B to IC2.IC2 is locked loop with audio decoder chip LM567 internalvoltage-controlled oscillator center frequency of f0 1/1.1R8C3 capacitor C4 determinetheir target bandwidth.R8-conditioning in the launch of the carrier frequency on theLM567 input signal is greater than 25mV the output from the high jump 8 feet into alow-level as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit output port INT0 interrupt thehighest priority right or left location of the output circuit with output gate IC3A accessINT1 port single-chip while single-chip P1.3 and P1.4 received input IC3A interrupted ‐10‐ 畢業(yè)設(shè)計(jì)（論文）英文翻譯by the process to identify the source of inquiry to deal with interrupt priority level for thefirst left right after.Part of the source code is as follows:receive1: push psw push acc clr ex1 related external interrupt 1 jnb p1.1 right P1.1 pin to 0 ranging from right to interrupt serviceroutine circuit jnb p1.2 left P1.2 pin to 0 to the left ranging circuit interruptservice routinereturn: SETB EX1 open external interrupt 1 pop acc pop psw retiright:...right location entrance circuit interrupt service routine Ajmp Returnleft:...left Ranging entrance circuit interrupt service routine Ajmp Return3.3 The calculation of ultrasonic propagation time When you start firing at the same time start the single-chip circuitry within the timerT0 the use of timer counting function records the time and the launch of ultrasonicreflected wave received time.When you receive the ultrasonic reflected wave the receivercircuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates asignal single-chip microcomputer in response to external interrupt request theimplementation of the external interrupt service subroutine read the time differencecalculating the distance.Some of its source code is as follows:RECEIVE0: PUSH PSW PUSH ACC CLR EX0 related external interrupt 0.

第二篇：超聲波測(cè)距外文翻譯文獻(xiàn)

超聲波測(cè)距畢業(yè)論文中英文對(duì)照資料外文翻譯文獻(xiàn)

超聲測(cè)距技術(shù)在工業(yè)現(xiàn)場(chǎng)、車輛導(dǎo)航、水聲工程等領(lǐng)域都具有廣泛的應(yīng)用價(jià)值，目前已應(yīng)用于物位測(cè)量、機(jī)器人自動(dòng)導(dǎo)航以及空氣中與水下的目標(biāo)探測(cè)、識(shí)別、定位等場(chǎng)合。因此，深入研究超聲的測(cè)距理論和方法具有重要的實(shí)踐意義。為了進(jìn)一步提高測(cè)距的精確度，滿足工程人員對(duì)測(cè)量精度、測(cè)距量程和測(cè)距儀使用的要求，本文研制了一套基于單片機(jī)的便攜式超聲測(cè)距系統(tǒng)。隨著技術(shù)的發(fā)展，人們生活水平的提高，城市發(fā)展建設(shè)加快，城市給排水系統(tǒng)也有較大展，其狀況不斷改善。但是，由于歷史原因合成時(shí)間住的許多不可預(yù)見因素，城市給排水系統(tǒng)，特別是排水系統(tǒng)往往落后于城市建設(shè)。因此，經(jīng)常出現(xiàn)開挖已經(jīng)建設(shè)好的建筑設(shè)施來改造排水系統(tǒng)的現(xiàn)象。城市污水給人們帶來了困擾，因此箱涵的排污疏通對(duì)大城市給排水系統(tǒng)污水處理，人們生活舒適顯得非常重要。而設(shè)計(jì)研制箱涵排水疏通移動(dòng)機(jī)器人的自動(dòng)控制系統(tǒng)，保證機(jī)器人在箱涵中自由排污疏通，是箱涵排污疏通機(jī)器人的設(shè)計(jì)研制的核心部分?？刂葡到y(tǒng)核心部分就是超聲波測(cè)距儀的研制。因此，設(shè)計(jì)好的超聲波測(cè)距儀就顯得非常重要了。波測(cè)距原理

2.1 壓電式超聲波發(fā)生器原理 壓電式超聲波發(fā)生器實(shí)際上是利用壓電晶體的諧振來工作的。超聲波發(fā)生器內(nèi)部結(jié)構(gòu)，它有兩個(gè)壓電晶片和一個(gè)共振板。當(dāng)它的兩極外加脈沖信號(hào)，其頻率等于壓電晶片的固有振蕩頻率時(shí)，壓電晶片將會(huì)發(fā)生共振，并帶動(dòng)共振板振動(dòng)，便產(chǎn)生超聲波。反之，如果兩電極間未外加電壓，當(dāng)共振板接收到超聲波 時(shí)，將壓迫壓電晶片作振動(dòng)，將機(jī)械能轉(zhuǎn)換為電信號(hào)，這時(shí)它就成為超聲波接收器了。測(cè)量脈沖到達(dá)時(shí)間的傳統(tǒng)方法是以擁有固定參數(shù)的接收信號(hào)開端為基礎(chǔ)的。這個(gè)界限恰恰選于噪音水平之上，然而脈沖到達(dá)時(shí)間被定義為脈沖信號(hào)剛好超過界限的第一時(shí)刻。一個(gè)物體的脈沖強(qiáng)度很大程度上取決于這個(gè)物體的自然屬性尺寸還有它與傳感器的距離。進(jìn)一步說，從脈沖起始點(diǎn)到剛好超過界限之間的時(shí)間段隨著脈沖的強(qiáng)度而改變。結(jié)果，一種錯(cuò)誤便出現(xiàn)了——兩個(gè)擁有不同強(qiáng)度的脈沖在不同時(shí)間超過界限卻在同一時(shí)間到達(dá)。強(qiáng)度較強(qiáng)的脈沖會(huì)比強(qiáng)度較弱的脈沖超過界限的時(shí)間早點(diǎn)，因此我們會(huì)認(rèn)為強(qiáng)度較強(qiáng)的脈沖屬于較近的物體。

2.2 聲波測(cè)距原理

超聲波發(fā)射器向某一方向發(fā)射超聲波，在發(fā)射時(shí)刻的同時(shí)開始計(jì)時(shí)，超聲波在空氣中傳播，途中碰到障礙物就立即返回來，超聲波接收器收到反射波就立即停止計(jì)時(shí)。超聲波在空氣中的傳播速度為 340m/s，根據(jù)計(jì)時(shí)器記錄的時(shí)間 t，就可以計(jì)算出發(fā)射點(diǎn)距障礙物的距離s，即：s340t/2 3 波測(cè)距系統(tǒng)的電路設(shè)計(jì)

系統(tǒng)的特點(diǎn)是利用單片機(jī)控制超聲波的發(fā)射和對(duì)超聲波自發(fā)射至接收往返時(shí)間的計(jì)時(shí)，單片機(jī)選用 C51，經(jīng)濟(jì)易用，且片內(nèi)有 4K 的 ROM，便于編程。

3.1 40kHz 脈沖的產(chǎn)生與超聲波發(fā)射 測(cè)距系統(tǒng)中的超聲波傳感器采用

UCM40 的壓電陶瓷傳感器，它的工作電壓是40kHz 的脈沖信號(hào)，這由單片機(jī)執(zhí)行下面程序來產(chǎn)生。puzel： mov 14h 12h；超聲波發(fā)射持續(xù) 200mshere： cpl p1.0 ； 輸出 40kHz 方波 nop ； nop ； nop ； djnz 14h，here； ret 前方測(cè)距電路的輸入端接單片機(jī) P1.0 端口，單片機(jī)執(zhí)行上面的程序后，在 P1.0端口輸出一個(gè) 40kHz 的脈沖信號(hào)，經(jīng)過三極管 T 放大，驅(qū)動(dòng)超聲波發(fā)射頭 UCM40T，發(fā)出 40kHz 的脈沖超聲波，且持續(xù)發(fā)射 200ms。右側(cè)和左側(cè)測(cè) 距電路的輸入端分別接 P1.1 和 P1.2 端口，工作原理與前方測(cè)距電路相同。

3.2 超聲波的接收與處理

接收頭采用與發(fā)射頭配對(duì)的 UCM40R，將超聲波調(diào)制脈沖變?yōu)榻蛔冸妷盒盘?hào)，經(jīng) IC2運(yùn)算放大器 IC1A 和 IC1B 兩極放大后加至 IC2。是帶有鎖 定環(huán)的音頻譯碼集成塊LM567，內(nèi)部的壓控振蕩器的中心頻率 f01/1.1R8C3，電容 C4 決定其鎖定帶寬。調(diào)節(jié) R8 在發(fā)射的載頻上，則 LM567 輸入信號(hào)大于 25mV，輸出端 8 腳由高電平躍變?yōu)榈碗娖?，作為中斷?qǐng)求信號(hào)，送至單片機(jī)處理.前方測(cè)距電路的輸出端接單片機(jī) INT0 端口，中斷優(yōu)先級(jí)最高，左、右測(cè)距電路的輸出通過與門 IC3A 的輸出接單片機(jī) INT1 端口，同時(shí)單片機(jī) P1.3 和 P1.4 接到 IC3A的輸入端，中斷源的識(shí)別由程序查詢來處理，中斷優(yōu)先級(jí)為先右后左。部分源程序如下：receive1：push psw push acc clr ex1； 關(guān)外部中斷 1 jnb p1.1right；P1.1 引腳為 0轉(zhuǎn)至右測(cè)距電路中斷服務(wù)程序 jnb p1.2left；P1.2 引腳為 0轉(zhuǎn)至左測(cè)距電路中斷服務(wù)程序return： SETB EX1； 開外部中斷 1 pop acc pop psw retiright：...； 右測(cè)距電路中斷服務(wù)程序入口 ajmp returnleft：...； 左測(cè)距電路中斷服務(wù)程序入口 ajmp return 3.3 計(jì)算超聲波傳播時(shí)間

在啟動(dòng)發(fā)射電路的同時(shí)啟動(dòng)單片機(jī)內(nèi)部的定時(shí)器 T0，利用定時(shí)器的計(jì)數(shù)功能記錄超聲波發(fā)射的時(shí)間和收到反射波的時(shí)間。當(dāng)收到超聲波反射波時(shí)，接收電路 輸出端產(chǎn)生一個(gè)負(fù)跳變，在 INT0 或 INT1 端產(chǎn)生一個(gè)中斷請(qǐng)求信號(hào)，單片機(jī)響應(yīng)外部中斷請(qǐng)求，執(zhí)行外部中斷服務(wù)子程序，讀取時(shí)間差，計(jì)算距離。其部分源程序如下：RECEIVE0： PUSH PSW PUSH ACC CLR EX0 ； 關(guān)外部中斷 0 MOV R7 TH0 ； 讀取時(shí)間值 MOV R6 TL0 CLR C MOV A R6 SUBB A 0BBH； 計(jì)算時(shí)間差 MOV 31H A ； 存儲(chǔ)結(jié)果 MOV A R7 SUBB A 3CH MOV 30H A SETB EX0 ； 開外部中斷 0 POP ACC POP PSW RETI對(duì)于一個(gè)平坦的目標(biāo)，距離測(cè)量包括兩個(gè)階段:粗糙的測(cè)量和精細(xì)測(cè)量。第一步：脈沖的傳送產(chǎn)生一種簡(jiǎn)單的超聲波。第二步：根據(jù)公式改變回波放大器的獲得量直到回?fù)鼙粰z測(cè)到。第三步：檢測(cè)兩種回波的振幅與過零時(shí)間。第四步：設(shè)置回波放大器的所得來規(guī)格輸出，假定是 3 伏。通過脈沖的周期設(shè)置下一 個(gè)脈沖。根據(jù)第二部的數(shù)據(jù)設(shè)定時(shí)間窗。第五步：發(fā)射兩串脈沖產(chǎn)生干擾波。測(cè)量過零時(shí)間與回波的振幅。如果逆向發(fā)生在回 波中，決定要不通過在低氣壓插入振幅。第六步：通過公式計(jì)算距離 y。波測(cè)距系統(tǒng)的軟件設(shè)計(jì)

軟件分為兩部分，主程序和中斷服務(wù)程序。主程序完成初始化工作、各路超聲波發(fā)射和接收順序的控制。定時(shí)中斷服務(wù)子程序完成三方向超聲波的輪流發(fā)射，外部中斷服務(wù)子程序主要完成時(shí)間值的讀取、距離計(jì)算、結(jié)果的輸出等工作。對(duì)所要求測(cè)量范圍 30cm200cm 內(nèi)的平面物體做了多次測(cè)量發(fā)現(xiàn)，其最大誤差為0.5cm，且重復(fù)性好?？梢娀趩纹瑱C(jī)設(shè)計(jì)的超聲波測(cè)距系統(tǒng)具有硬件結(jié)構(gòu)簡(jiǎn)單、工作可靠、測(cè)量誤差小等特點(diǎn)。因此，它不僅可用于移動(dòng)機(jī)器人，還可用在其它檢測(cè)系統(tǒng)中。思考：至于為什么接收不用晶體管做放大電路呢，因?yàn)榉糯蟊稊?shù)搞不好，集成放大電路，還帶自動(dòng)電平增益控制，放大倍數(shù)為 76dB，中心頻率是 38k 到 40k，剛好是超聲波傳感器的諧振頻率。

原文出處：傳感器文摘 布拉福德:1993年 第13頁(yè)摘要

Ultrasonic ranging technology has wide using worth in many fields，such as the industriallocale，vehicle navigation and sonar engineering．Now it has been used in level measurement，self-guided autonomous vehicles fieldwork robots automotive navigation，air and underwater targetdetection，identification，location and so on．So there is an important practicing meaning to learn theranging theory and ways deeply.To improve the precision of the ultrasonic ranging system in hand，satisfy the request of the engineering personnel for the ranging precision，the bound and the usage，aportable ultrasonic ranging system based on the single chip processor was developed 1.With the development of science and technology the improvement of peoplesstandard of living speeding up the development and construction of the city.urbandrainage system have greatly developed their situation is constantly improving.Howeverdue to historical reasons many unpredictable factors in the synthesis of her time the citydrainage system.In particular drainage system often lags behind urban construction.Therefore there are often good building excavation has been building facilities to upgradethe drainage system phenomenon.It brought to the city sewage and it is clear to the citysewage and drainage culvert in the sewage treatment system.comfort is very important topeoples lives.Mobile robots designed to clear the drainage culvert and the automaticcontrol system Free sewage culvert clear guarantee robot the robot is designed to clear theculvert sewage to the core.Control System is the core component of the development ofultrasonic range finder.Therefore it is very important to design a good ultrasonic rangefinder.2.A principle of ultrasonic distance measurement

2.1 The principle of piezoelectric ultrasonic generator Piezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work.Ultrasonic generator the internal structure as shown it has two piezoelectric chip and aresonance plate.When its two plus pulse signal the frequency equal to the intrinsicpiezoelectric oscillation frequency chip the chip will happen piezoelectric resonance andpromote the development of plate vibration resonance ultrasound is generated.Converselyif the two are not inter-electrode voltage when the board received ultrasonic resonance itwill be for vibration suppression of piezoelectric chip the mechanical energy is convertedto electrical signals then it becomes the ultrasonic receiver.The traditional way to determine the moment of the echos arrival is based onthresholding the received signal with a fixed reference.The threshold is chosen well abovethe noise level whereas the moment of arrival of an echo is defined as the first moment theecho signal surpasses that threshold.The intensity of an echo reflecting from an objectstrongly depends on the objects nature size and distance from the sensor.Further the timeinterval from the echos starting point to the moment when it surpasses the thresholdchanges with the intensity of the echo.As a consequence a considerable error may occurEven two echoes with different intensities arriving exactly at the same time will surpass thethreshold at different moments.The stronger one will surpass the threshold earlier than theweaker so it will be considered as belonging to a nearer object.2.2The principle of ultrasonic distance measurement Ultrasonic transmitter in a direction to launch ultrasound in the moment to launch thebeginning of time at the same time the spread of ultrasound in the air obstacles on his wayto return immediately the ultrasonic reflected wave received by the receiver immediatelystop the clock.Ultrasound in the air as the propagation velocity of 340m / s according tothe timer records the time t we can calculate the distance between the launch distancebarrier s that is: s 340t / 2 3.Ultrasonic Ranging System for the Second Circuit Design System is characterized by single-chip microcomputer to control the use of ultrasonictransmitter and ultrasonic receiver since the launch from time to time single-chip selectionof 8751 economic-to-use and the chip has 4K of ROM to facilitate programming.Circuitschematic diagram shown in Figure 2.Figure 1 circuit principle diagram

3.1 40 kHz ultrasonic pulse generated with the launch Ranging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40its operating voltage of the pulse signal is 40kHz which by the single-chip implementationof the following procedures to generate.puzel: mov 14h 12h ultrasonic firing continued 200mshere: cpl p1.0 output 40kHz square wave nop nop nop djnz 14h here ret Ranging in front of single-chip termination circuit P1.0 input port single chipimplementation of the above procedure the P1.0 port in a 40kHz pulse output signal afteramplification transistor T the drive to launch the first ultrasonic UCM40T issued 40kHzultrasonic pulse and the continued launch of 200ms.Ranging the right and the left side ofthe circuit respectively then input port P1.1 and P1.2 the working principle and circuit infront of the same location.3.2 Reception and processing of ultrasonic Used to receive the first launch of the first pair UCM40R the ultrasonic pulsemodulation signal into an alternating voltage the op-amp amplification IC1A and afterpolarization IC1B to IC2.IC2 is locked loop with audio decoder chip LM567 internalvoltage-controlled oscillator center frequency of f0 1/1.1R8C3 capacitor C4 determinetheir target bandwidth.R8-conditioning in the launch of the carrier frequency on theLM567 input signal is greater than 25mV the output from the high jump 8 feet into alow-level as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit output port INT0 interrupt thehighest priority right or left location of the output circuit with output gate IC3A accessINT1 port single-chip while single-chip P1.3 and P1.4 received input IC3A interrupted by the process to identify the source of inquiry to deal with interrupt priority level for thefirst left right after.Part of the source code is as follows:receive1: push psw push acc clr ex1 related external interrupt 1 jnb p1.1 right P1.1 pin to 0 ranging from right to interrupt serviceroutine circuit jnb p1.2 left P1.2 pin to 0 to the left ranging circuit interruptservice routinereturn: SETB EX1 open external interrupt 1 pop acc pop psw retiright:...right location entrance circuit interrupt service routine Ajmp Returnleft:...left Ranging entrance circuit interrupt service routine Ajmp Return 3.3 The calculation of ultrasonic propagation time When you start firing at the same time start the single-chip circuitry within the timerT0 the use of timer counting function records the time and the launch of ultrasonicreflected wave received time.When you receive the ultrasonic reflectedwave the receivercircuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates asignal single-chip microcomputer in response to external interrupt request theimplementation of the external interruptservice subroutine read the time differencecalculating the distance.Some of its source code is as follows: RECEIVE0: PUSH PSW PUSH ACC CLR EX0;related external interrupt 0 MOV R7, TH0;read the time value MOV R6, TL0 CLR C MOV A, R6 SUBB A, # 0BBH;calculate the time difference MOV 31H, A;storage results MOV A, R7 SUBB A, # 3CH MOV 30H, A SETB EX0;open external interrupt 0 POP ACC POP PSW RETI For a flat target, a distance measurement consists of two phases: a coarse measurement and.a fine measurement: Step 1: Transmission of one pulse train to produce a simple ultrasonic wave.Step 2: Changing the gain of both echo amplifiers according to equati-on , until the echo is detected.Step 3: Detection of the amplitudes and zero-crossing times of both echoes.Step 4: Setting the gains of both echo amplifiers to normalize the output at, say 3 volts.Setting the period of the next pulses according to the : period of echoes.Setting the time window according to the data of step 2.Step 5: Sending two pulse trains to produce an interfered wave.Testing the zero-crossing times and amplitudes of the echoes.If phase inversion occurs in the echo, determine to otherwise calculate to by interpolation using the amplitudes near the trough.Derive t sub m1 and t sub m2.Step 6: Calculation of the distance y using equation.4.The ultrasonic ranging system software design Software is divided into two parts, the main program and interrupt service routine.Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Interrupt service routines from time to time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on..5.Conclusions Required measuring range of 30cm ~ 200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility.Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error.Therefore, it can be used not only for mobile robot can be used in other detection systems.Thoughts: As for why the receiver do not have the transistor amplifier circuit, because the magnification well, integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.Ultrasonic ranging system design Publication title: Sensor Review.Bradford: 1993.Vol.13

第三篇：中英文對(duì)照資料外文翻譯文獻(xiàn)

中英文對(duì)照資料外文翻譯文獻(xiàn)

平設(shè)計(jì)任何時(shí)期平面設(shè)計(jì)可以參照一些藝術(shù)和專業(yè)學(xué)科側(cè)重于視覺傳達(dá)和介紹。采用多種方式相結(jié)合，創(chuàng)造和符號(hào)，圖像和語(yǔ)句創(chuàng)建一個(gè)代表性的想法和信息。平面設(shè)計(jì)師可以使用印刷，視覺藝術(shù)和排版技術(shù)產(chǎn)生的最終結(jié)果。平面設(shè)計(jì)常常提到的進(jìn)程，其中溝通是創(chuàng)造和產(chǎn)品設(shè)計(jì)。共同使用的平面設(shè)計(jì)包括雜志，廣告，產(chǎn)品包裝和網(wǎng)頁(yè)設(shè)計(jì)。例如，可能包括產(chǎn)品包裝的標(biāo)志或其他藝術(shù)作品，舉辦文字和純粹的設(shè)計(jì)元素，如形狀和顏色統(tǒng)一件。組成的一個(gè)最重要的特點(diǎn)，尤其是平面設(shè)計(jì)在使用前現(xiàn)有材料或不同的元素。平面設(shè)計(jì)涵蓋了人類歷史上諸多領(lǐng)域，在此漫長(zhǎng)的歷史和在相對(duì)最近爆炸視覺傳達(dá)中的第20和21世紀(jì)，人們有時(shí)是模糊的區(qū)別和重疊的廣告藝術(shù)，平面設(shè)計(jì)和美術(shù)。畢竟，他們有著許多相同的內(nèi)容，理論，原則，做法和語(yǔ)言，有時(shí)同樣的客人或客戶。廣告藝術(shù)的最終目標(biāo)是出售的商品和服務(wù)。在平面設(shè)計(jì)，“其實(shí)質(zhì)是使以信息，形成以思想，言論和感覺的經(jīng)驗(yàn)”。在唐朝（618-906）之間的第4和第7世紀(jì)的木塊被切斷打印紡織品和后重現(xiàn)佛典。阿藏印在868是已知最早的印刷書籍。在19世紀(jì)后期歐洲，尤其是在英國(guó)，平面設(shè)計(jì)開始以獨(dú)立的運(yùn)動(dòng)從美術(shù)中分離出來。蒙德里安稱為父親的圖形設(shè)計(jì)。他是一個(gè)很好的藝術(shù)家，但是他在現(xiàn)代廣告中利用現(xiàn)代電網(wǎng)系統(tǒng)在廣告、印刷和網(wǎng)絡(luò)布局網(wǎng)格。于1849年，在大不列顛亨利科爾成為的主要力量之一在設(shè)計(jì)教育界，該國(guó)政府通告設(shè)計(jì)在雜志設(shè)計(jì)和制造的重要性。他組織了大型的展覽作為慶祝現(xiàn)代工業(yè)技術(shù)和維多利亞式的設(shè)計(jì)。從1892年至1896年威廉?莫里斯凱爾姆斯科特出版社出版的書籍的一些最重要的平面設(shè)計(jì)產(chǎn)品和工藝美術(shù)運(yùn)動(dòng)，并提出了一個(gè)非常賺錢的商機(jī)就是出版?zhèn)ゴ笪谋菊摰膱D書并以高價(jià)出售給富人。莫里斯證明了市場(chǎng)的存在使平面設(shè)計(jì)在他們自己擁有的權(quán)利，并幫助開拓者從生產(chǎn)和美術(shù)分離設(shè)計(jì)。這歷史相對(duì)論是，然而，重要的，因?yàn)樗鼮榈谝淮沃卮蟮姆磻?yīng)對(duì)于十九世紀(jì)的陳舊的平面設(shè)計(jì)。莫里斯的工作，以及與其他私營(yíng)新聞運(yùn)動(dòng)，直接影響新藝術(shù)風(fēng)格和間接負(fù)責(zé)20世紀(jì)初非專業(yè)性平面設(shè)計(jì)的事態(tài)發(fā)展。誰(shuí)創(chuàng)造了最初的“平面設(shè)計(jì)”似乎存在爭(zhēng)議。這被歸因于英國(guó)的設(shè)計(jì)師和大學(xué)教授Richard Guyatt，但另一消息來源于20世紀(jì)初美國(guó)圖書設(shè)計(jì)師William Addison Dwiggins。倫敦地鐵的標(biāo)志設(shè)計(jì)是愛德華約翰斯頓于1916年設(shè)計(jì)的一個(gè)經(jīng)典的現(xiàn)代而且使用了系統(tǒng)字體設(shè)計(jì)。在20世紀(jì)20年代，蘇聯(lián)的建構(gòu)主義應(yīng)用于“智能生產(chǎn)”在不同領(lǐng)域的生產(chǎn)。個(gè)性化的運(yùn)動(dòng)藝術(shù)在 2 俄羅斯大革命是沒有價(jià)值的，從而走向以創(chuàng)造物體的功利為目的。他們?cè)O(shè)計(jì)的建筑、劇院集、海報(bào)、面料、服裝、家具、徽標(biāo)、菜單等。Jan Tschichold 在他的1928年書中編纂了新的現(xiàn)代印刷原則，他后來否認(rèn)他在這本書的法西斯主義哲學(xué)主張，但它仍然是非常有影響力。Tschichold，包豪斯印刷專家如赫伯特拜耳和拉斯洛莫霍伊一納吉，和El Lissitzky 是平面設(shè)計(jì)之父都被我們今天所知。他們首創(chuàng)的生產(chǎn)技術(shù)和文體設(shè)備，主要用于整個(gè)二十世紀(jì)。隨后的幾年看到平面設(shè)計(jì)在現(xiàn)代風(fēng)格獲得廣泛的接受和應(yīng)用。第二次世界大戰(zhàn)結(jié)束后，美國(guó)經(jīng)濟(jì)的建立更需要平面設(shè)計(jì)，主要是廣告和包裝等。移居國(guó)外的德國(guó)包豪斯設(shè)計(jì)學(xué)院于1937年到芝加哥帶來了“大規(guī)模生產(chǎn)”極簡(jiǎn)到美國(guó);引發(fā)野火的“現(xiàn)代”建筑和設(shè)計(jì)。值得注意的名稱世紀(jì)中葉現(xiàn)代設(shè)計(jì)包括阿德里安Frutiger，設(shè)計(jì)師和Frutiger字體大學(xué);保蘭德，從20世紀(jì)30年代后期，直到他去世于1996年，采取的原則和適用包豪斯他們受歡迎的廣告和標(biāo)志設(shè)計(jì)，幫助創(chuàng)造一個(gè)獨(dú)特的辦法，美國(guó)的歐洲簡(jiǎn)約而成為一個(gè)主要的先驅(qū)。平面設(shè)計(jì)稱為企業(yè)形象;約瑟夫米勒，羅克曼，設(shè)計(jì)的海報(bào)嚴(yán)重尚未獲取1950年代和1960年代時(shí)代典型。從道路標(biāo)志到技術(shù)圖表，從備忘錄到參考手冊(cè)，增強(qiáng)了平面設(shè)計(jì)的知識(shí)轉(zhuǎn)讓?？勺x性增強(qiáng)了文字的視覺效果。設(shè)計(jì)還可以通過理念或有效的視覺傳播幫助銷售產(chǎn)品。將它應(yīng)用到產(chǎn)品和公司識(shí)別系統(tǒng)的要素像標(biāo)志、顏色和文字。連同這些被定義為品牌。品牌已日益成為重要的提供的服務(wù)范圍，許多平面設(shè)計(jì)師，企業(yè)形象和條件往往是同時(shí)交替使用。教科書的目的是本科目，如地理、科學(xué)和數(shù)學(xué)。這些出版物已布局理論設(shè)計(jì)說明和圖表。一個(gè)常見的例子，在使用圖形，教育是圖表人體解剖學(xué)。平面設(shè)計(jì)也適用于布局和格式的教育材料，使信息更容易和更容易理解的。平面設(shè)計(jì)是應(yīng)用在娛樂行業(yè)的裝飾，景觀和視覺故事。其他的例子娛樂設(shè)計(jì)用途包括小說，漫畫，電影中的開幕和閉幕，在舞臺(tái)上節(jié)目的和道具的安排。這也包括藝術(shù)品在T恤衫的應(yīng)用和其他物品的出售。從科學(xué)雜志報(bào)道，提出意見和事實(shí)往往是提高圖形和深思熟慮的組成視覺信息-被稱為信息的設(shè)計(jì)。報(bào)紙，雜志，博客，電視和電影紀(jì)錄片，可以使用平面設(shè)計(jì)通知及娛樂。隨著網(wǎng)絡(luò)，信息與經(jīng)驗(yàn)的交互設(shè)計(jì)的工具，Adobe和Flash正越來越多地被用來說明的背景新聞。一個(gè)平面設(shè)計(jì)項(xiàng)目可能涉及程式化和介紹現(xiàn)有的文字，或者事先存在的意向或圖像開發(fā)的平面設(shè)計(jì)師。例如，一家報(bào)紙的故事始于記者和攝影記者，然后成為平面設(shè)計(jì)師的工作安排到一個(gè)合理的頁(yè)面布局，并確定是否有任何其他圖形元素應(yīng)當(dāng)要求。在一本雜志的文章或廣告，往往是平面設(shè)計(jì)師或藝術(shù)總監(jiān)將委員會(huì)攝影師或插圖創(chuàng)建原始文件只是被納入設(shè)計(jì)規(guī)劃?，F(xiàn)代設(shè)計(jì)的做法已經(jīng)擴(kuò)展到了現(xiàn)代的計(jì)算機(jī)，例如在使用所見的用戶界面，通常被稱為交互式設(shè)計(jì)，或多媒體設(shè)計(jì)。任何圖形元素用于設(shè)計(jì)之前，圖形元素必須是源于通過視覺藝術(shù)技能。這些圖形通常（但并不總是）被設(shè)計(jì)師開發(fā)。視覺藝術(shù)的作品主要是視覺性的東西從使用傳統(tǒng)的傳播媒介、攝影或電腦產(chǎn)生的藝術(shù)。平面設(shè)計(jì)原則可以適用于每一個(gè)人的版畫藝術(shù)元素，并最終組成。3 印刷術(shù)是藝術(shù)，工藝和技術(shù)型，修改類型字形，并安排類型的設(shè)計(jì)。類型字形（字符）的創(chuàng)建和修改使用各種說明方法。這項(xiàng)安排的類型是選擇字體、大小、線長(zhǎng)、主要的（行距）和文字的間距。刷術(shù)是由排字工機(jī)，排字，印刷工人，圖形藝術(shù)家，藝術(shù)總監(jiān)，工作者和辦事員。直到數(shù)字時(shí)代，印刷成為一個(gè)專業(yè)的領(lǐng)域。數(shù)字化開辟了新的視覺設(shè)計(jì)師和用戶。排版設(shè)計(jì)師平面設(shè)計(jì)的一部分，是在網(wǎng)頁(yè)設(shè)計(jì)中是圖形設(shè)計(jì)，處理安排風(fēng)格（內(nèi)容）的要素。從早期的照明網(wǎng)頁(yè)手工復(fù)制書籍的中世紀(jì)和程序，以錯(cuò)綜復(fù)雜的現(xiàn)代雜志和目錄布局，適當(dāng)?shù)木W(wǎng)頁(yè)設(shè)計(jì)公司長(zhǎng)期以來一直是考慮的印刷材料，與印刷媒體，內(nèi)容通常包括類型（文字，圖片（照片）偶爾發(fā)生持有者圖形的內(nèi)容，沒有印刷油墨，如模具/激光切割，燙金壓印或盲目壓花。平面設(shè)計(jì)師常常專心研究于界面設(shè)計(jì)，如網(wǎng)頁(yè)設(shè)計(jì)和軟件設(shè)計(jì)，最終用戶的交互性是一個(gè)設(shè)計(jì)考慮的布局或接口。視覺溝通技巧、互動(dòng)溝通技巧與用戶互動(dòng)得相結(jié)合和在線品牌推廣，平面設(shè)計(jì)師往往與軟件開發(fā)和網(wǎng)絡(luò)開發(fā)人員創(chuàng)建的外觀和風(fēng)格的網(wǎng)站或軟件應(yīng)用程序，來加強(qiáng)用戶或網(wǎng)絡(luò)網(wǎng)站的訪問者互動(dòng)體驗(yàn)。版畫是在紙上，其他有機(jī)材料或者表面上印刷藝術(shù)品的過程。每一張不會(huì)被復(fù)制，但時(shí)最初的因?yàn)樗皇且粋€(gè)復(fù)制的另一藝術(shù)作品，并在技術(shù)上稱為留下深刻的印象。繪畫或素描，另一方面，創(chuàng)造了獨(dú)特的原始藝術(shù)品。版畫是由一個(gè)單一的原始表面創(chuàng)造的，在技術(shù)上已經(jīng)作為基質(zhì)而被已知。常見的矩陣包括：金屬板，通常是銅或鋅的雕刻或蝕刻石料，用于光刻;塊木刻的木材，油氈和織物板的絲網(wǎng)印刷。但也有許多其他種類，討論如下：作品從一個(gè)單一的印刷板創(chuàng)造一個(gè)版本，在現(xiàn)代通常每個(gè)簽署和編號(hào)，形成限量。打印也可編制成冊(cè)，作為藝術(shù)家的書籍。一個(gè)單一的打印可能是產(chǎn)品的一種或多種技術(shù)。色彩學(xué)領(lǐng)域是如何在打印機(jī)上和顯示器上用眼睛識(shí)別顏色和如何解釋和組織這些色彩。眼睛的視網(wǎng)膜被兩個(gè)被命名為視桿和視錐的感光體涵蓋。視桿對(duì)光很敏感但是對(duì)顏色不是很敏感。視錐卻與視桿恰恰相反。他們對(duì)光不太敏感，但是顏色可以被感知。隨著科技的發(fā)展，人們?cè)絹碓秸J(rèn)識(shí)到環(huán)境問題日益嚴(yán)重，大氣污染、森林破壞、水土流失、土地沙漠

化、水資源污染、大量物種滅絕、石油、天然氣、煤等資源枯竭。作為工業(yè)設(shè)計(jì)師，應(yīng)該有強(qiáng)烈的環(huán)境 保護(hù)意識(shí)，使得自己的設(shè)計(jì)建立在不破壞環(huán)境及節(jié)約自然資源的基礎(chǔ)上。

其中，溫室效應(yīng)、臭氧層破壞和酸雨是當(dāng)今全球性的三大環(huán)境問題。

溫室效應(yīng)就是大氣變暖的效應(yīng)其形成原因是太陽(yáng)短波輻射可以透過大氣射入地面，而地面增暖后放

出的長(zhǎng)波輻射卻被大氣中的二氧化碳就像一層厚厚的玻璃，把地球變成了一個(gè)大暖房。甲烷、臭氧、氯、氟烴以及水汽等也對(duì)溫室效應(yīng)有所貢獻(xiàn)。隨著人口的急劇增加和工業(yè)的迅速發(fā)展，越來越多的二氧化碳 排入大氣中；

又由于森林被大量砍伐，大氣中原本應(yīng)被森林吸收的二氧化碳沒有被吸收，致使二氧化碳 逐漸增加，溫室效應(yīng)也不斷增強(qiáng)。溫室效應(yīng)的后果十分嚴(yán)重，自然生態(tài)將隨之發(fā)生重大變化，荒漠將擴(kuò)

大，土地侵蝕加重，森林退向極地，旱澇災(zāi)害嚴(yán)重，雨量增加；溫帶冬天更濕、夏天更旱；熱帶也將變 得更濕，干熱的亞熱帶變得更干旱，迫使原有水利工程重新調(diào)整。沿海將受到嚴(yán)重威脅。由于氣溫升高，兩極冰塊將融化，使海平面上升，將會(huì)淹沒許多城市和港口。

臭氧層破壞現(xiàn)象引起科學(xué)界及整個(gè)國(guó)際社會(huì)的震動(dòng)。美國(guó)的兩位科學(xué)家 Monila 和 Rowland 指出，正是人為的活動(dòng)造成了今天的臭氧洞。元兇就是現(xiàn)在所熟知的氟利昂和哈龍。

酸雨目前已成為一種范圍廣泛、跨越國(guó)界的大氣污染現(xiàn)象。酸雨破壞土壤，使湖泊酸化，危害動(dòng)植

物生長(zhǎng)；刺激人的皮膚，誘發(fā)皮膚病，引起肺水腫、肺硬化；會(huì)腐蝕金屬制品、油漆、皮革、紡織品和 含碳酸鹽的建筑。

總而言之，人類生活的環(huán)境已經(jīng)日益惡化。

而惡化的原因大部分屬于人類本身的不良生活方式和不 尊重客觀規(guī)律，急功近利，對(duì)于地球資源的使用沒有科學(xué)的計(jì)劃性，而且在設(shè)計(jì)、制造產(chǎn)品以及日常生

活中缺乏保護(hù)環(huán)境的意識(shí)，以至于自毀家園，其危害不僅于當(dāng)代，而且嚴(yán)重影響了子孫后代的生存。

環(huán)境問題在很大程度上是由于人們的不良設(shè)計(jì)、生活方式造成的后果。于是給設(shè)計(jì)師們提出了一個(gè)

嚴(yán)肅的問題：作為設(shè)計(jì)師，應(yīng)肩負(fù)起保護(hù)環(huán)境的歷史重任！

工業(yè)在為人類創(chuàng)造大量物質(zhì)財(cái)富的同時(shí)，也給世界帶來了災(zāi)難。工業(yè)設(shè)計(jì)在為人類創(chuàng)造了現(xiàn)代生活

方式的同時(shí)，也加速了資源、能源的消耗，并對(duì)地球的生態(tài)平衡造成了巨大的破壞。

所以，作為工業(yè)設(shè)計(jì)師，建立環(huán)境意識(shí)體現(xiàn)了其道德和社會(huì)責(zé)任心。設(shè)計(jì)師必須對(duì)自己的設(shè)計(jì)負(fù)責(zé)，必須把人類的健康幸福，自然與人類的和諧共存作為設(shè)計(jì)中心遵循的原則。

設(shè)計(jì)師還必須掌握必要的材料、工藝、化工、制造等方面的知識(shí)，使得其設(shè)計(jì)不對(duì)環(huán)境造成危害而 成為可能。

“可持續(xù)發(fā)展設(shè)計(jì)” 這一概念的提出，對(duì)于人性的回歸及世界真正意義上的發(fā)展具有劃時(shí)代的意義。他體現(xiàn)了設(shè)計(jì)師的道德與責(zé)任，已成為 21 世紀(jì)設(shè)計(jì)發(fā)展的總趨勢(shì)。從此，人類傳統(tǒng)工業(yè)文明發(fā)展模式

轉(zhuǎn)向現(xiàn)代生態(tài)文明發(fā)展模式。它是社會(huì)進(jìn)步，經(jīng)濟(jì)增長(zhǎng)，環(huán)境保護(hù)三者之間的協(xié)同。

可持續(xù)發(fā)展是人們應(yīng)遵循的一種全新的倫理、道德和價(jià)值觀念。其本質(zhì)在于：充分利用現(xiàn)代科技，大力開發(fā)綠色資源，發(fā)展清潔生產(chǎn)，不斷改善和優(yōu)化生態(tài)環(huán)境，促使人與自然的和諧發(fā)展，人口、資源 和環(huán)境相互協(xié)調(diào)。

解決可持續(xù)反展問題是一個(gè)技術(shù)創(chuàng)新和行為模式轉(zhuǎn)變的問題。

可持續(xù)發(fā)展戰(zhàn)略是解決在不危害未來幾代人的需求前提下，盡量滿足當(dāng)代人的需求的問題。實(shí)現(xiàn)目

前利益與長(zhǎng)遠(yuǎn)利益的統(tǒng)一，為子孫后代留下發(fā)展空間。

目前可持續(xù)發(fā)展戰(zhàn)略考慮的問題有：循環(huán)性、綠色能源、生態(tài)效率。

綠色設(shè)計(jì)源于人們對(duì)于現(xiàn)代技術(shù)文化所引起的環(huán)境及生態(tài)破壞的反思。綠色設(shè)計(jì)著眼于人與自然的

生態(tài)平衡關(guān)系，在設(shè)計(jì)過程的每一個(gè)決策中都充分考慮到環(huán)境效益，盡量減少對(duì)環(huán)境的破壞。

對(duì)工業(yè)設(shè)計(jì)師而言，綠色設(shè)計(jì)的核心是“ 3R ”，即“減少”（Reduce）、“再循環(huán)”(Recycle)和“再 利用”（Reuse)。不僅要盡量減少物質(zhì)和能源的消耗、減少有害物質(zhì)的排放，而且要使產(chǎn)品及零件能夠 5 方便的分類回收，并再生循環(huán)或重新利用。

綠色設(shè)計(jì)不僅是一種技術(shù)層面的考慮，更重要的是一種觀念 上的變革。

要求設(shè)計(jì)師放棄那種過分強(qiáng)調(diào)產(chǎn)品在外觀上標(biāo)新立異的做法，而將重點(diǎn)放在真正意義上的創(chuàng) 新上面，已一種更為負(fù)責(zé)的方法去創(chuàng)造產(chǎn)品的形態(tài)，用更簡(jiǎn)潔、長(zhǎng)久的造型使產(chǎn)品盡可能地延長(zhǎng)其使用 壽命。

從材料方面要考慮： 原材料的存量和可再生性，獲取材料時(shí)的環(huán)境能源的消耗與污染，后續(xù)加工時(shí)

環(huán)境材料的易加工性，低能耗性、低污染性，報(bào)廢時(shí)的可回收性。

從加工制造方面要考慮：加工制造階段需要將污染減至最少，或?qū)⑽廴鞠麥缭谏a(chǎn)過程初始階段。

從包裝、運(yùn)輸、銷售等方面要考慮：包裝的環(huán)境性能、綠色包裝，良好的可運(yùn)輸性、降低自重、減 少能耗，當(dāng)?shù)鼗a(chǎn)及減少物流過程消耗。

從產(chǎn)品的使用階段考慮： 使用中的能耗、資源消耗。

產(chǎn)品更新?lián)Q代時(shí)環(huán)境性能的模塊化、可重組性、產(chǎn)品的使用模式等因素。

從產(chǎn)品的報(bào)廢階段考慮：易拆卸性，便于分解和分類，材料可回收性和可再利用性，零部件可重組 性或移作它用等因素。

清潔的能源：如考慮太陽(yáng)能、水電、風(fēng)力的清潔燃料；清潔的材料，涉及低污染、無毒、易降解和 可回收性；清潔的制造過程，考慮低能耗、少排放的制造；清潔的產(chǎn)品，涉及使用中節(jié)能、環(huán)保、報(bào)廢 后的回收。

零部件的再生利用濕可持續(xù)戰(zhàn)略的有力措施。事實(shí)證明： 報(bào)廢的產(chǎn)品拆卸后，經(jīng)分析，其中材料在

改進(jìn)設(shè)計(jì)后可重用和經(jīng)翻新后可重用的比例可以提高。

比如：一輛報(bào)廢車中，金屬材料占 80 ％，其中，有色金屬占 3 ％～ 4.7 ％。世界鋼產(chǎn)量中的 45 ％是 由廢鋼鐵生產(chǎn)出的。中國(guó)鋼產(chǎn)量的 25 ％是由廢鋼鐵生產(chǎn)的。

產(chǎn)品全生命周期管理是指從人對(duì)產(chǎn)品的需求開始，到產(chǎn)品淘汰報(bào)廢的全部生命歷程。其中包括產(chǎn)

品需求分析產(chǎn)品計(jì)劃、概念設(shè)計(jì)、產(chǎn)品設(shè)計(jì)、數(shù)字化仿真、工藝準(zhǔn)備、工藝規(guī)劃、生產(chǎn)測(cè)試和質(zhì)量監(jiān)控、銷售與分銷、使用、維護(hù)與維修，以及報(bào)廢與回收等主要階段。將先進(jìn)的管理理念和一流的信息技術(shù)有

機(jī)融入到現(xiàn)代企業(yè)的工業(yè)和商業(yè)運(yùn)作中，從而使企業(yè)在數(shù)字經(jīng)濟(jì)時(shí)代能夠有效地調(diào)整經(jīng)營(yíng)手段和管理方式，以發(fā)揮企業(yè)前所未有的競(jìng)爭(zhēng)優(yōu)勢(shì)。幫助企業(yè)進(jìn)行產(chǎn)品創(chuàng)新，贏得市場(chǎng)，并獲得額外利潤(rùn)，以提高企業(yè)產(chǎn)品的價(jià)值。

GRAPHIC DESIGN The term graphic design can refer to a number of artistic and professional disciplines which focus on visual communication and presentation.Various methods are used to create and combine symbols, images and/or words to create a visual representation of ideas and messages.A graphic designer may use typography, visual arts and page layout techniques to produce the final result.Graphic design often refers to both the process by which the communication is created and the products which are generated.Common uses of graphic design include magazines, advertisements, product packaging and web design.For example, a product package might include a logo or other artwork, organized text and pure design elements such as shapes and color which unify the piece.Composition is one of the most important features of graphic design especially when using pre-existing materials or diverse elements.Graphic Design spans the history of humankind from the caves of Lascaux to the dazzling neons of Ginza.In both this lengthy history and in the relatively recent explosion of visual communication in the 20th and 21st centuries, there is sometimes a blurring distinction and over-lapping of advertising art, graphic design and fine art.After all, they share many of the same elements, theories, principles, practices and languages, and sometimes the same benefactor or client.In advertising art the ultimate objective is the sale of goods and services.In graphic design, “the essence is to give order to information, form to ideas, expression and feeling to artifacts that document human experience.” During the Tang dynasty(618–906)between the 4th and 7th century A.D.wood blocks were cut to print on textiles and later to reproduce Buddhist texts.A Buddhist scripture printed in 868 is the earliest known printed book.In late 19th century Europe, especially in the United Kingdom, the movement began to separate graphic design from fine art.Piet Mondrian is known as the father of graphic design.He was a fine artist, but his use of grids inspired the modern grid system used today in advertising, print and web layout.In 1849, Henry Cole became one of the major forces in design education in Great Britain, informing the government of the importance of design in his Journal of Design and Manufactures.He organized the Great Exhibition as a celebration of modern industrial technology and Victorian design.From 1892 to 1896 William Morris' Kelmscott Press published books that are some of the most significant of the graphic design products of the Arts and Crafts movement, and 2 made a very lucrative business of creating books of great stylistic refinement and selling them to the wealthy for a premium.Morris proved that a market existed for works of graphic design in their own right and helped pioneer the separation of design from production and from fine art.The work of the Kelmscott Press is characterized by its obsession with historical styles.This historicism was, however, important as it amounted to the first significant reaction to the stale state of nineteenth-century graphic design.Morris' work, along with the rest of the Private Press movement, directly influenced Art Nouveau and is indirectly responsible for developments in early twentieth century graphic design in general.Who originally coined the term “graphic design” appears to be in dispute.It has been attributed to Richard Guyatt, the British designer and academic, but another source suggests William Addison Dwiggins, an American book designer in the early 20th century The signage in the London Underground is a classic of the modern era and used a font designed by Edward Johnston in 1916.In the 1920s, Soviet constructivism applied 'intellectual production' in different spheres of production.The movement saw individualistic art as useless in revolutionary Russia and thus moved towards creating objects for utilitarian purposes.They designed buildings, theater sets, posters, fabrics, clothing, furniture, logos, menus, etc.Jan Tschichold codified the principles of modern typography in his 1928 book, New Typography.He later repudiated the philosophy he espoused in this book as being fascistic, but it remained very influential.Tschichold, Bauhaus typographers such as Herbert Bayer and Laszlo Moholy-Nagy, and El Lissitzky are the fathers of graphic design as we know it today.They pioneered production techniques and stylistic devices used throughout the twentieth century.The following years saw graphic design in the modern style gain widespread acceptance and application.A booming post-World War II American economy established a greater need for graphic design, mainly advertising and packaging.The emigration of the German Bauhaus school of design to Chicago in 1937 brought a “mass-produced”minimalism to America;sparking a wild fire of “modern”architecture and design.Notable names in mid-century modern design include Adrian Frutiger, designer of the typefaces Univers and Frutiger;Paul Rand, who, from the late 1930s until his death in 1996, took the principles of the Bauhaus and applied them to popular advertising and logo design, helping to create a uniquely American approach to European minimalism while becoming one of the principal pioneers of the subset of graphic design known as corporate identity；and Josef Müller-Brockmann, who designed posters in a severe yet accessible manner typical of the 1950s and 1960s era.3 From road signs to technical schematics, from interoffice memorandums to reference manuals, graphic design enhances transfer of knowledge.Readability is enhanced by improving the visual presentation of text.Design can also aid in selling a product or idea through effective visual communication.It is applied to products and elements of company identity like logos, colors, and text.Together these are defined as branding(see also advertising).Branding has increasingly become important in the range of services offered by many graphic designers, alongside corporate identity, and the terms are often used interchangeably.Textbooks are designed to present subjects such as geography, science, and math.These publications have layouts which illustrate theories and diagrams.A common example of graphics in use to educate is diagrams of human anatomy.Graphic design is also applied to layout and formatting of educational material to make the information more accessible and more readily understandable.Graphic design is applied in the entertainment industry in decoration, scenery, and visual story telling.Other examples of design for entertainment purposes include novels, comic books, opening credits and closing credits in film, and programs and props on stage.This could also include artwork used for t-shirts and other items screenprinted for sale.From scientific journals to news reporting, the presentation of opinion and facts is often improved with graphics and thoughtful compositions of visual information-known as information design.Newspapers, magazines, blogs, television and film documentaries may use graphic design to inform and entertain.With the advent of the web, information designers with experience in interactive tools such as Adobe Flash are increasingly being used to illustrate the background to news stories.A graphic design project may involve the stylization and presentation of existing text and either preexisting imagery or images developed by the graphic designer.For example, a newspaper story begins with the journalists and photojournalists and then becomes the graphic designer's job to organize the page into a reasonable layout and determine if any other graphic elements should be required.In a magazine article or advertisement, often the graphic designer or art director will commission photographers or illustrators to create original pieces just to be incorporated into the design layout.Contemporary design practice has been extended to the modern computer, for example in the use of WYSIWYG user interfaces, often referred to as interactive design, or multimedia design.Before any graphic elements may be applied to a design, the graphic elements must be originated by means of visual art skills.These graphics are often(but not always)developed 4 by a graphic designer.Visual arts include works which are primarily visual in nature using anything from traditional media, to photography or computer generated art.Graphic design principles may be applied to each graphic art element individually as well as to the final composition.Typography is the art, craft and techniques of type design, modifying type glyphs, and arranging type.Type glyphs(characters)are created and modified using a variety of illustration techniques.The arrangement of type is the selection of typefaces, point size, line length, leading(line spacing)and letter spacing.Typography is performed by typesetters, compositors, typographers, graphic artists, art directors, and clerical workers.Until the Digital Age, typography was a specialized occupation.Digitization opened up typography to new generations of visual designers and lay users.Page layout is the part of graphic design that deals in the arrangement and style treatment of elements(content)on a page.Beginning from early illuminated pages in hand-copied books of the Middle Ages and proceeding down to intricate modern magazine and catalog layouts, proper page design has long been a consideration in printed material.With print media, elements usually consist of type(text), images(pictures), and occasionally place-holder graphics for elements that are not printed with ink such as die/laser cutting, foil stamping or blind embossing.Graphic designers are often involved in interface design, such as web design and software design when end user interactivity is a design consideration of the layout or interface.Combining visual communication skills with the interactive communication skills of user interaction and online branding, graphic designers often work with software developers and web developers to create both the look and feel of a web site or software application and enhance the interactive experience of the user or web site visitor.Printmaking is the process of making artworks by printing on paper and other materials or surfaces.Except in the case of monotyping, the process is capable of producing multiples of the same piece, which is called a print.Each piece is not a copy but an original since it is not a reproduction of another work of art and is technically known as an impression.Painting or drawing, on the other hand, create a unique original piece of artwork.Prints are created from a single original surface, known technically as a matrix.Common types of matrices include: plates of metal, usually copper or zinc for engraving or etching;stone, used for lithography;blocks of wood for woodcuts, linoleum for linocuts and fabric plates for screen-printing.But there are many other kinds, discussed below.Works printed from a single

第四篇：食品安全外文文獻(xiàn)翻譯(適用于畢業(yè)論文外文翻譯+中英文對(duì)照)

w 論食品供應(yīng)鏈管理和食品質(zhì)量安全

上世紀(jì)90年代以來,供應(yīng)鏈管理已成為學(xué)術(shù)界和實(shí)業(yè)界關(guān)注的熱門話題,特別是供應(yīng)鏈管理成功地應(yīng)用于IBM、P&G、DELL 等公司的經(jīng)營(yíng)管理以后,食品和農(nóng)產(chǎn)品行業(yè)也紛紛效仿并借助供應(yīng)鏈管理這一工具來提高自身的競(jìng)爭(zhēng)力。1996年,Zuurbier等學(xué)者在一般供應(yīng)鏈的基礎(chǔ)上，首次提出了食品供應(yīng)鏈概念，并認(rèn)為食品供應(yīng)鏈管理是農(nóng)產(chǎn)品和食品生產(chǎn)銷售等組織,為了降低食品和農(nóng)產(chǎn)品物流成本、提高其質(zhì)量安全和物流服務(wù)水平而進(jìn)行的垂直一體化運(yùn)作模式。如今,在美國(guó)、英國(guó)、加拿大和荷蘭等農(nóng)業(yè)生產(chǎn)較為發(fā)達(dá)的國(guó)家,這一管理模式已經(jīng)廣為應(yīng)用,并逐漸成為當(dāng)今學(xué)術(shù)研究的重點(diǎn)課題。

對(duì)食品供應(yīng)鏈管理的研究大致經(jīng)歷了三個(gè)階段：第一階段為商流管理階段，研究范圍包括農(nóng)產(chǎn)品和食品加工企業(yè)的產(chǎn)出到消費(fèi)者消費(fèi)前的商流階段，其研究?jī)?nèi)容通常被包含在營(yíng)銷范疇內(nèi)；第二階段為集成物流管理階段，農(nóng)產(chǎn)品的物流管理從市場(chǎng)營(yíng)銷中分離出來，且向上游擴(kuò)展到農(nóng)產(chǎn)品和食品生產(chǎn)企業(yè)的生產(chǎn)加工過程，強(qiáng)調(diào)生產(chǎn)應(yīng)以市場(chǎng)需求為導(dǎo)向和對(duì)整個(gè)物流環(huán)節(jié)的成本控制；第三階段為供應(yīng)鏈一體化管理階段，研究范圍進(jìn)一步向上游延伸到農(nóng)產(chǎn)品的最上游企業(yè)(如種子供應(yīng)商等)，延伸的目的是為了跟蹤和追溯農(nóng)產(chǎn)品食品質(zhì)量安全問題，以便快速和有效地發(fā)現(xiàn)并解決問題。本文介紹了不同食品供應(yīng)鏈的生產(chǎn)物流系統(tǒng)特點(diǎn)，并對(duì)食品供應(yīng)鏈與食品質(zhì)量安全管理的發(fā)展進(jìn)行了分析和探討。

一．食品供應(yīng)鏈管理的產(chǎn)生原因

近年來，食品供應(yīng)鏈的產(chǎn)生和發(fā)展是人們對(duì)食品消費(fèi)的要求不斷提高的必然結(jié)果。具體而言，產(chǎn)生的原因主要有：(1)消費(fèi)者對(duì)食品和農(nóng)產(chǎn)品的新鮮度要求越來越高，并要求食品和農(nóng)產(chǎn)品交貨期、生產(chǎn)期越短越好。(2)消費(fèi)者對(duì)食品和農(nóng)產(chǎn)品的質(zhì)量要求也越來越高，迫使食品生產(chǎn)企業(yè)實(shí)行食品供應(yīng)鏈管理，以保證穩(wěn)定的上游原料供應(yīng)和下游的銷售渠道暢通。(3)消費(fèi)者對(duì)食品的質(zhì)量安全也越來越關(guān)注。為了滿足消費(fèi)者對(duì)食品和農(nóng)產(chǎn)品在種類和數(shù)量上的要求，企業(yè)不斷尋求和研發(fā)新技術(shù)，而新技術(shù)和新方法的過度使用(如殺蟲劑、激素、抗生素和轉(zhuǎn)

w 基因技術(shù)等)，在滿足了消費(fèi)者需求的同時(shí)，也不可避免地對(duì)人體產(chǎn)生了危害從而引起食品質(zhì)量安全問題。這是因?yàn)槭袌?chǎng)中買賣雙方信息不對(duì)稱,消費(fèi)者在購(gòu)買食品或農(nóng)產(chǎn)品時(shí)，不了解產(chǎn)品的衛(wèi)生、環(huán)保和安全信息。因此，企業(yè)有必要在生產(chǎn)過程的各個(gè)環(huán)節(jié)對(duì)產(chǎn)品進(jìn)行檢驗(yàn)和檢測(cè)并及時(shí)向消費(fèi)者披露這些信息。(4)食品和農(nóng)產(chǎn)品企業(yè)迫于政府、相關(guān)社會(huì)組織和消費(fèi)者的要求和壓力，不得不按食品供應(yīng)鏈來進(jìn)行運(yùn)作。例如，歐盟管理法規(guī)第178號(hào)規(guī)定，從2004年起在歐盟范圍內(nèi)銷售的所有食品，都要實(shí)行食品供應(yīng)鏈跟蹤與追溯；同樣在美國(guó)，食品與藥品管理局規(guī)定，在美國(guó)國(guó)內(nèi)外從事食品生產(chǎn)、加工和包裝等的部門以及相關(guān)組織，在2003年12月12日前要向食品與藥品管理局進(jìn)行登記，以便進(jìn)行食品安全跟蹤與追溯，未登記者就不許從事食品生產(chǎn)和銷售。由此可見，食品供應(yīng)鏈管理是在市場(chǎng)內(nèi)在動(dòng)力和政府外在壓力的情況下促成的。

二．食品供應(yīng)鏈生產(chǎn)物流系統(tǒng)

食品供應(yīng)鏈的形成是與其物流系統(tǒng)的內(nèi)容不斷變化密切相關(guān)的,特別是在食品和農(nóng)產(chǎn)品生產(chǎn)物流系統(tǒng)不斷演變的情況下,為人們創(chuàng)建高效率的食品供應(yīng)鏈管理范式提供了基礎(chǔ)。根據(jù)食品和農(nóng)產(chǎn)品物流的發(fā)展階段,典型的食品供應(yīng)鏈可劃分為啞鈴型、T型、對(duì)稱型和混合型四種類型。

1.啞鈴型食品供應(yīng)鏈。這種類型的食品供應(yīng)鏈嚴(yán)格來說是一種準(zhǔn)供應(yīng)鏈。它的特點(diǎn)是供應(yīng)鏈較短,連接位于兩端的交易主體很多,而中間鏈節(jié)少且交易主體也較少，呈現(xiàn)為啞鈴型。由于上游生產(chǎn)者擁有的技術(shù)條件較差、產(chǎn)量低和品種少，故上游聚集了為數(shù)眾多的農(nóng)產(chǎn)品生產(chǎn)者；同時(shí)，由于產(chǎn)品生產(chǎn)地離市場(chǎng)較近且只提供單一農(nóng)產(chǎn)品，也又使得鏈中參與交易的主體大多為農(nóng)產(chǎn)品生產(chǎn)者，他們?cè)谑袌?chǎng)上進(jìn)行直接交易，而少有聯(lián)系生產(chǎn)者和消費(fèi)者之間的中間商，因此，種植業(yè)者直接將食品和農(nóng)產(chǎn)品銷售給消費(fèi)者。在發(fā)展中國(guó)家,特別是靠近城鎮(zhèn)地區(qū)的蔬菜供應(yīng),一般都采用這種類型的供應(yīng)鏈。

2.T型食品供應(yīng)鏈。這種類型的食品供應(yīng)鏈一般適用于食品和農(nóng)產(chǎn)品的生產(chǎn)地和銷售地相距較遠(yuǎn)，消費(fèi)需求差異較大的情況。由于農(nóng)產(chǎn)品易腐爛，農(nóng)產(chǎn)品生產(chǎn)者不可能直接銷售自己的產(chǎn)品,需要通過必要的中間商提供服務(wù),如第三方物流、農(nóng)產(chǎn)品深加工商和批發(fā)商等所提供的相應(yīng)服務(wù)。這種類型的供應(yīng)鏈，上游聚

w 集了較多的農(nóng)產(chǎn)品生產(chǎn)者,而在中游環(huán)節(jié)對(duì)產(chǎn)地生產(chǎn)情況比較了解,又在銷售地占有一定渠道優(yōu)勢(shì)的銷售商卻較少。因此,T型食品供應(yīng)鏈的上游種植業(yè)者眾多,而中下游中間商和銷售商較少且集中,供應(yīng)鏈的形狀呈現(xiàn)為 T型。與啞鈴型食品供應(yīng)鏈相比,它的鏈條較長(zhǎng),食品和農(nóng)產(chǎn)品的銷售表現(xiàn)為間接性和增值服務(wù)性。這種類型的食品供應(yīng)鏈在中國(guó)較為普遍，在中國(guó)農(nóng)業(yè)產(chǎn)業(yè)化不發(fā)達(dá)的地區(qū),由于缺乏一端連接上游農(nóng)戶，另一端聯(lián)結(jié)銷售市場(chǎng)、專門從事農(nóng)產(chǎn)品加工的龍頭企業(yè)以及相應(yīng)的中間環(huán)節(jié)，農(nóng)產(chǎn)品生產(chǎn)往往和市場(chǎng)需求相脫節(jié)。因此T型食品供應(yīng)鏈由于中間環(huán)節(jié)缺位和低水平的物流運(yùn)作，易出現(xiàn)上游農(nóng)戶盲目生產(chǎn)而下游農(nóng)產(chǎn)品銷售困難的現(xiàn)象。

3.對(duì)稱型食品供應(yīng)鏈。隨著新興銷售業(yè)態(tài)的出現(xiàn),銷售渠道日益被大型專業(yè)市場(chǎng)和超市所壟斷,農(nóng)產(chǎn)品和食品的傳統(tǒng)銷售形式也被超市所取代,而且這種趨勢(shì)越來越明顯,同時(shí)由于技術(shù)水平的提高,農(nóng)產(chǎn)品生產(chǎn)也趨向于由少數(shù)種植商集約經(jīng)營(yíng)。Boselie.D通過對(duì)泰國(guó)皇家阿荷生鮮超市食品供應(yīng)鏈管理的調(diào)查發(fā)現(xiàn),曼谷有50%的食品和農(nóng)產(chǎn)品是在大型超市(如7-

11、皇家阿荷、家樂福、Sainsburry和TESCO)售出的。這些大型超市為了滿足市場(chǎng)對(duì)農(nóng)產(chǎn)品品質(zhì)一致性和供應(yīng)穩(wěn)定性的要求，對(duì)供應(yīng)商進(jìn)行了嚴(yán)格的篩選。因此，皇家阿荷生鮮超市實(shí)施食品供應(yīng)鏈管理后，將供應(yīng)商從原來的250家減少為60家左右，使物流系統(tǒng)更加高效和簡(jiǎn)潔。隨著上游農(nóng)產(chǎn)品供應(yīng)商數(shù)目的銳減和超市連鎖店的不斷擴(kuò)張，這種食品供應(yīng)鏈的上游供應(yīng)商與下游超市連鎖店的數(shù)目呈現(xiàn)對(duì)稱增長(zhǎng)之態(tài)勢(shì)。在發(fā)達(dá)國(guó)家及物流發(fā)展較為成熟的大城市里，這種食品供應(yīng)鏈經(jīng)常表現(xiàn)為集中采購(gòu)、統(tǒng)一流通配送和減少不增值的物流環(huán)節(jié),以實(shí)現(xiàn)節(jié)約成本的精益物流戰(zhàn)略。

4.混合型食品供應(yīng)鏈。隨著市場(chǎng)食品和農(nóng)產(chǎn)品消費(fèi)需求的多樣化，食品和農(nóng)產(chǎn)品加工的比重也在逐步提高。據(jù)有關(guān)統(tǒng)計(jì)表明，美國(guó)2002未加工和加工蔬菜的比例為15%和85%；水果為30%和70%。其他國(guó)家的情況也大致如此。大型超市為了適應(yīng)消費(fèi)需求的顯著變化，將原先由獨(dú)立企業(yè)從事的專業(yè)化生產(chǎn)的增值環(huán)節(jié)進(jìn)行“內(nèi)部化”，專門建立大型加工及配送中心，對(duì)農(nóng)產(chǎn)品進(jìn)行清洗、分類、深度加工、包裝和配送等增值業(yè)務(wù)，同時(shí)通過在大型加工中心實(shí)施HACCP和GMP加工質(zhì)量和衛(wèi)生安全認(rèn)證，來保證食品和農(nóng)產(chǎn)品的品質(zhì)安全。這個(gè)環(huán)節(jié)是前述三個(gè)食品供應(yīng)鏈中所沒有的，這是大型超市和連鎖店對(duì)市場(chǎng)需求作出快速反

w 應(yīng)的結(jié)果。隨著上游供應(yīng)商實(shí)力和優(yōu)勢(shì)的增強(qiáng)，加工中心的部分功能，如清洗、分類和深度加工等環(huán)節(jié)又向供應(yīng)商回流，使得加工中心的重點(diǎn)放在處理和不斷擴(kuò)大的農(nóng)產(chǎn)品數(shù)量和種類業(yè)務(wù)上。因此，這種食品供應(yīng)鏈?zhǔn)且环N綜合型、多品種、大批量和多頻次的混合型供應(yīng)鏈體系。這種食品供應(yīng)鏈更關(guān)注消費(fèi)者的滿意度，通過加工中心來對(duì)市場(chǎng)需求作出快速反應(yīng)，并實(shí)時(shí)對(duì)農(nóng)產(chǎn)品和食品進(jìn)行“量身定制”和深度加工，以實(shí)現(xiàn)不同于精益物流的靈捷物流戰(zhàn)略。

三．食品供應(yīng)鏈跟蹤與食品質(zhì)量安全

近年來，由于食品供應(yīng)鏈合作的重點(diǎn)由原來的保證供貨質(zhì)量逐步轉(zhuǎn)向加強(qiáng)食品和農(nóng)產(chǎn)品的質(zhì)量安全，如瘋牛病、口蹄疫和轉(zhuǎn)基因食品等的出現(xiàn)。農(nóng)產(chǎn)品和食品質(zhì)量安全的跟蹤離不開食品供應(yīng)鏈管理，因此基于質(zhì)量安全的食品供應(yīng)鏈跟蹤成了食品供應(yīng)鏈管理的重點(diǎn)和難點(diǎn)。Golan.E等通過對(duì)美國(guó)生鮮農(nóng)產(chǎn)品、谷類和油菜以及牛肉制品的調(diào)查研究發(fā)現(xiàn)，三者經(jīng)食品供應(yīng)鏈跟蹤后，在食品質(zhì)量安全方面出現(xiàn)了很大的差異。而分析這些差異，他們又發(fā)現(xiàn)三種農(nóng)產(chǎn)品食品供應(yīng)鏈管理的共性，即存在三種驅(qū)動(dòng)力。這也是企業(yè)實(shí)施食品供應(yīng)鏈管理時(shí)需要分析考察的問題：

1.有利于食品和農(nóng)產(chǎn)品差別化營(yíng)銷，以提高食品和農(nóng)產(chǎn)品的銷量。通過那些細(xì)小的或不能直接發(fā)現(xiàn)的食品質(zhì)量安全的特性，可區(qū)別不同類型的農(nóng)產(chǎn)品和食品。因?yàn)樵谑称泛娃r(nóng)產(chǎn)品市場(chǎng)上不僅存在大量單一的谷類和肉類產(chǎn)品，而且也有根據(jù)消費(fèi)者不同的偏好和口味量身定制的食品。有些農(nóng)產(chǎn)品和食品的質(zhì)量可能容易判別，而另一些則不容易直接判別，甚至在消費(fèi)之后也不能馬上發(fā)現(xiàn)其質(zhì)量問題。例如，轉(zhuǎn)基因食用油，如未進(jìn)行標(biāo)識(shí)，消費(fèi)者就很難判別食用油是否由非轉(zhuǎn)基因大豆加工而成。因此，對(duì)農(nóng)產(chǎn)品和食品的安全質(zhì)量和品質(zhì)進(jìn)行細(xì)分，是差別化營(yíng)銷的必要前提。

2.有利于農(nóng)產(chǎn)品和食品質(zhì)量安全的跟蹤，減少食品和農(nóng)產(chǎn)品召回成本。許多企業(yè)已利用食品供應(yīng)鏈跟蹤系統(tǒng)，來最大限度地減少食品安全體系缺陷可能造成的潛在損失。供應(yīng)商通常有著很強(qiáng)的經(jīng)濟(jì)驅(qū)動(dòng)性，當(dāng)發(fā)現(xiàn)食品有安全隱患和質(zhì)量問題時(shí)，他們往往會(huì)采取措施，避免食品質(zhì)量安全問題給企業(yè)自身或品牌帶來負(fù)面的影響?；谑称饭?yīng)鏈的跟蹤能幫助企業(yè)縮短確認(rèn)和清理有問題食品的時(shí)

w 間，為此，國(guó)外許多企業(yè)將相關(guān)標(biāo)識(shí)信息揭示在食品包裝上，以便利消費(fèi)者的識(shí)別和認(rèn)定。例如，在美國(guó)大多數(shù)要求召回的食品和農(nóng)產(chǎn)品都被公布在美國(guó)農(nóng)業(yè)部食品安全和檢驗(yàn)服務(wù)的官方網(wǎng)站上，以便消費(fèi)者根據(jù)食品包裝的標(biāo)識(shí)信息來判定有問題的食品和農(nóng)產(chǎn)品。有些企業(yè)則通過使用先進(jìn)RSS條碼系統(tǒng)和EAN/UCC全球統(tǒng)一標(biāo)識(shí)系統(tǒng)，更為具體地揭示食品供應(yīng)鏈的標(biāo)識(shí)信息，如每種產(chǎn)品的種子、施肥、使用抗生素的情況、生產(chǎn)時(shí)間、生產(chǎn)線、生產(chǎn)地、生產(chǎn)所使用的技術(shù)和生產(chǎn)次序，等等。因此某種產(chǎn)品一旦出現(xiàn)問題，這些標(biāo)識(shí)信息將能夠發(fā)揮很大的作用。

目前，歐盟已經(jīng)采用EAN/UCC系統(tǒng)，成功地開展了對(duì)牛肉、蔬菜等食品追蹤的研究。通過采用EAN/UCC-128條碼符號(hào)、GLN(全球位置碼)可以對(duì)食品供應(yīng)鏈全過程中的產(chǎn)品及其屬性信息和參與方信息等進(jìn)行有效的標(biāo)識(shí)。在對(duì)食品跟蹤與追溯時(shí)，要求供應(yīng)鏈中的每一道加工環(huán)節(jié)，不僅要對(duì)自己所加工完成的產(chǎn)品進(jìn)行標(biāo)識(shí)，還要采集所需加工的食品原料上的已有標(biāo)識(shí)信息，并將其全部信息標(biāo)識(shí)在加工完成的產(chǎn)品上，以備下一道加工環(huán)節(jié)或消費(fèi)者使用，從而有效地解決了供應(yīng)鏈各環(huán)節(jié)之間的聯(lián)系比較脆弱、實(shí)施跟蹤和追溯難度大的問題，也為企業(yè)減少因缺乏明確信息而將混在優(yōu)質(zhì)食品中的劣質(zhì)食品連同優(yōu)質(zhì)食品一同處理的可能性。

3.有利于提高和改善供應(yīng)方的物流管理。對(duì)于企業(yè)來說，管理生產(chǎn)物流和跟蹤相關(guān)零售信息(如條形碼)，能幫助企業(yè)了解其食品供應(yīng)鏈的物流流出狀況，以便對(duì)供應(yīng)鏈上游物流的流入進(jìn)行有效管理。特別是有些企業(yè)采用了基于質(zhì)量安全的食品供應(yīng)鏈的高新技術(shù)追溯系統(tǒng)，如農(nóng)場(chǎng)主使用電子耳標(biāo)識(shí)和相關(guān)數(shù)據(jù)收集卡來跟蹤食品和農(nóng)產(chǎn)品的免疫記錄、健康記錄和飼養(yǎng)記錄等。這些食品供應(yīng)鏈的信息也能使食品或農(nóng)產(chǎn)品在市場(chǎng)上獲得與其質(zhì)量相符的價(jià)格。

然而，對(duì)所有食品和農(nóng)產(chǎn)品都實(shí)施食品供應(yīng)鏈的質(zhì)量安全跟蹤是沒有必要的。Van Weele根據(jù)市場(chǎng)對(duì)農(nóng)產(chǎn)品和食品信息的需求，確定食品供應(yīng)鏈信息跟蹤的寬度、深度和精度。同理，企業(yè)對(duì)食品供應(yīng)鏈信息跟蹤的寬度、深度和精度也反映出其對(duì)基于質(zhì)量安全的食品供應(yīng)鏈的成本和收益的一種綜合取向。因?yàn)樾畔⒏櫟膶挾?、深度和精度決定著企業(yè)整合食品供應(yīng)鏈的投入和成本。只有當(dāng)收益大于成本時(shí)，企業(yè)所選擇的寬度、深度和精度才是實(shí)施供應(yīng)鏈質(zhì)量安全跟蹤的動(dòng)力和保證。

w Discussion on food supply chain management and food quality and safety

Since the 1990s, supply chain management has become the academic and business circles hot topic, especially in supply chain management successfully applied to IBM, P & G, DELL, etc.after the company's management, food and agricultural industries have followed suit and Supply chain management with a tool to improve their competitiveness.1996, Zuurbier and other scholars in general, on the basis of the supply chain, first proposed the concept of the food supply chain, and that the food supply chain management of agricultural and food production and marketing organization, food and agricultural products in order to reduce logistics costs and improve its quality and safety and logistics service level and for vertical integration mode of operation.Now, in the U.S., UK, Canada and the Netherlands and other more developed countries, agricultural production, this management model has been widely used, and gradually become the focus of academic research project.The food supply chain management research has gone through three stages: the first stage of the business flow management phase, the study of agricultural products and food processing enterprises, including the output of consumer spending to business before the flow phase, the content of their research is often included In the marketing context;the second stage of integrated logistics management phase, agricultural marketing, logistics management separate from, and to extend to the upstream producers of agricultural and food production process, emphasizing the production should be based on market demand and cost control throughout the supply chain;the third stage of supply chain integration management phase, the study extends further upstream to the most upstream agricultural enterprises(such as seed suppliers, etc.), the purpose is to extend the tracking and tracing of food quality and safety of

w agricultural products issues in order to quickly and effectively identify and solve problems.This article describes the production of different food supply chain logistics system characteristics, and the food supply chain management with the development of food quality and safety are analyzed and discussed.One.Food causes of supply chain management In recent years, the food supply chain, production and development of people's increasing demands for food consumption, the inevitable result.Specifically, the causes are:(1)the consumer fresh food and agricultural products have become increasingly demanding and require delivery of food and agricultural products, the production period as short as possible.(2)consumers of food and agricultural products quality requirements have become more sophisticated, forcing food manufacturers to implement the food supply chain management to ensure a stable supply of raw materials upstream and downstream sales channels.(3)food quality and safety of consumers are increasingly concerned about.In order to meet consumer demand for food and agricultural products in the type and quantity requirements, companies continue to seek and develop new technologies, and new technologies and new methods of excessive use(such as pesticides, hormones, antibiotics and genetically modified technology, etc.)to meet the consumer demand, but also inevitably produced a hazard causing human food quality and safety issues.This is because buyers and sellers in the market information asymmetry, consumers in the purchase of food or agricultural products, the products do not understand the health, environmental and safety information.Therefore, enterprises need in all aspects of the production process inspection and testing of products and timely disclosure of information to consumers.(4)food and agricultural companies forced the government, Relevant social

w organizations and consumer demands and pressure to press the food supply chain to operate.For example, EU regulations No.178, as from 2004 in all EU-wide sales of food, must be implemented to track and trace food supply chain;the same in the United States Food and Drug Administration regulations in the United States and abroad engaged in food production, processing and packaging departments and related organizations in the December 12, 2003 to register the Food and Drug Administration for food safety tracking and tracing, on the allowed unregistered persons engaged in food production and sales.Thus, the food supply chain management is inherent in the market dynamics and the external pressure the government to promote the case.Two.Food supply chain, production logistics system The formation of the food supply chain logistics system with the changing content of closely related, particularly in the food and agricultural production logistics system evolving situation, for people to create a highly efficient food supply chain management paradigm provides the basis.According to food and agricultural products logistics stage of development, typical of the food supply chain can be divided into dumbbell-shaped, T-, symmetric and mixed four types.1．dumbbell food supply chain.This type of food supply chain is a quasi-strict supply chain.It is characterized by a shorter supply chain, connecting the main lot located at both ends of the transaction, while the middle of the main chain are few and fewer transactions, showing the dumbbell type.Upstream producers have poor technical conditions, production is low and less variety, it gathered a large number of upstream agricultural producers;the same time, products from the market to close and only a single farm, it also makes the chain in Most of the main trading agricultural producers, their direct trading in the market, and little

w contact between producers and consumers, middlemen, so growers sell directly to consumers food and agricultural products.In developing countries, especially near urban areas, the supply of vegetables, generally using this type of supply chain.2.T type of food supply chain.This type of food supply chains are generally applicable to food and agricultural production and sales of land to the far distance, consumer demand quite different situation.As perishable agricultural products, agricultural producers can not sell their products directly, through intermediaries to provide the necessary services, such as third-party logistics, agricultural processors and wholesalers provide appropriate services.This type of supply chain, upstream gathered more producers, and in the middle part of a better understanding of the origin of production, but also in the sales channels to occupy a certain advantage, but fewer vendors.Therefore, T-food supply chain and many growers, brokers and sellers and less downstream and concentrated, showing the shape of the supply chain for the T-type.And dumbbell-shaped compared to the food supply chain, which chain is longer, the sales performance of food and agricultural products and value-added services for the indirect nature.This type of food supply chains more common in China, China's agriculture industry in less developed regions, due to lack of upstream farmers to connect one end, other end of the link sales market, specializing in the processing of agricultural products among leading enterprises and the corresponding part of agricultural production often out of line with market demand.Therefore, T-middle part of the food supply chain as a low level of absence and logistics operation, prone to upstream farmers and downstream production of agricultural products sold blindly difficult phenomenon.3．symmetric food supply chain.With the emergence of new sales formats, distribution channels are increasingly large-scale professional market

w and supermarket monopoly, the traditional sales of agricultural products and food forms have been replaced by supermarkets, and this trend is more and more obvious, and because of its technological level of agricultural products production also tends to intensive management by a few growers.Boselie.D Ahe by the Royal Thai supermarket fresh food supply chain management survey found that 50% of Bangkok's food and agricultural products in large supermarkets(such as 7-11, Royal Ahe, Carrefour, Sainsburry and TESCO)sold of.These large supermarkets in order to meet the market for agricultural products, quality consistency and supply stability requirements, the supplier of a rigorous screening.Therefore, the implementation of the Royal Ahe supermarket fresh food supply chain management, will be vendors from the original 250 was reduced to about 60, so that the logistics system more efficient and concise.With the upper reaches of the sharp drop in the number of suppliers of agricultural products and the continuous expansion of the supermarket chain, this food supply chain, upstream suppliers and downstream number of supermarket chains showed symmetrical growth trend.Logistics development in developed and more mature cities, this has been expressed in the food supply chain, centralized purchasing, reduce non-uniform flow distribution and value-added logistics sectors, in order to achieve cost savings of lean logistics strategy.4．mixed food supply chain.With consumer demand for food and agricultural products market diversification, the proportion of food and agricultural processing has gradually improved.According to the statistics that the United States in 2002 raw and processed vegetables for 15% and 85%;fruit of 30% and 70%.Other countries also generally the case.Large supermarkets in order to meet consumer demand significant changes to the original by an independent enterprise engaged in specialized production of value-added aspects of “internal” and

w specifically the establishment of large-scale processing and distribution center for agricultural products for cleaning, sorting, in-depth processing, packaging and distribution and other value-added services, through the implementation of HACCP in a large processing center and GMP certification process quality and health and safety, to ensure the quality of food and agricultural safety.The link is above three does not have the food supply chain, which is large supermarkets and chain stores to respond quickly to market demands results.With upstream suppliers to enhance the strength and advantages of the processing center part of the function, such as cleaning, sorting and depth of processing and other sectors Youxiang supplier back, making the processing center focused on the processing of agricultural products and expanding the number and type of business.Therefore, this food supply chain is a comprehensive, multi-species, multi-frequency high-volume and mix of supply chain system.This food supply chain are more concerned about customer satisfaction, through the processing centers to respond quickly to market demand, and real-time on agricultural products and foodstuffs “tailored” and depth of processing, in order to achieve different from the lean agile logistics logistics strategy.Three.Food supply chain tracking and food quality and safety In recent years, the focus of the food supply chain collaboration to ensure delivery of quality from the gradual move to reinforce the quality and safety of food and agricultural products, such as BSE, foot and mouth disease and the emergence of genetically modified foods.Agricultural products and food quality and safety of track without food supply chain management, so based on quality and safety of the food supply chain to track the food supply chain management has become important and difficult.Golan.E by the United States and other fresh produce, meat products，w cereals and oilseed rape, and survey findings, three by the food supply chain tracking, food quality and safety in that there are great differences.The analysis of these differences, they also found that three agricultural products common food supply chain management, that there are three driving forces.This is also the corporate implementation of the food supply chain management requires analysis examines the question: 1．will help differentiate the marketing of food and agricultural products to improve food and agricultural sales.Through those small or can not be directly found in food quality and safety features, can distinguish between different types of agricultural products and food.Because in the food and agricultural products on the market not only in large single grains and meat products, but also based on consumer preferences and tastes of different tailor-made food.Some agricultural products and food quality may be easier to distinguish, while others are not easy to directly determine, even after the consumer can not immediately find its quality.For example, transgenic edible oil, if not identified, the consumer it is difficult to determine whether the oil processed from non-genetically modified soybeans.Therefore, the quality of agricultural products and food safety and quality of the segmentation is a necessary prerequisite for differentiated marketing.2.is conducive to quality and safety of agricultural products and food tracking, reducing the cost of food and agricultural products recall.Many companies have used the food supply chain tracking systems to minimize food safety system deficiencies may result in potential losses.Suppliers often have a strong economy driven, when discovered food safety hazards and quality problems are, they tend to take measures to avoid food quality and safety issues to the companies themselves, or have a negative impact on the brand.Based on the food supply chain tracking can help businesses identify and reduce the time to clean up the food in question, for many

w foreign companies to reveal identifying information related to food packaging, to facilitate the identification of consumers and identified.For example, in the United States requested the recall of most food and agricultural products have been released in the United States Department of Agriculture Food Safety and Inspection Service's official website for consumers based on food packaging, identification information to determine the question of food and agricultural products.Some companies are using advanced RSS bar code system and EAN / UCC Global unified identification system, more specifically reveal the identity of the food supply chain information, such as the product of each seed, fertilizer, use of antibiotics, production time, production lines, production , the production technology used and the production order, and so on.Therefore, a product if there are problems, these identification information will be able to play a significant role.Currently, the EU has adopted EAN / UCC system, successfully carried out on beef, vegetables and other food tracking research.By using EAN/UCC-128 bar code symbol, GLN(Global Location Number)to the food supply chain and the whole process of product attribute information and participants information for effective identification.Tracking and traceability in the food, the requirements of the supply chain process in every aspect, not only to complete the processing of their products for identification, but also to collect the necessary processing of food materials has been on the identification information, and all information identified in the processing of finished products, to prepare for the next part of a process or consumer use, in order to effectively solve the supply chain link between the weak, difficult to track and trace the problem, but also for companies to reduce by lack of clear information and good food will be mixed in with the poor quality of food processing with the possibility of high-quality food.w 3．will help enhance and improve the supply side of logistics management.For businesses, the management of production logistics and track-related retail information(such as bar code), to help businesses understand their food supply chain, logistics and outflow conditions for the supply chain for effective management of logistics flows.In particular, some businesses have adopted based on the quality and safety of the food supply chain of high-tech tracking system, such as farmers use electronic ear identification cards and related data collection to track the immunization records of food and agricultural products, health records and breeding records.The food supply chain information can also make food or agricultural products in the market for its consistent quality and price.However, the implementation of all food and agricultural products quality and safety of the food supply chain tracking is not necessary.Van Weele, according to market information on agricultural and food needs of the food supply chain information to determine the track width, depth and accuracy.Similarly, companies in the food supply chain information to track width, depth and accuracy also reflects on the quality and safety of its food supply chain costs and benefits of an integrated approach.Because the information track width, depth and accuracy of a determinant of business investment in the food supply chain integration and cost.Only when the benefits outweigh the costs, the firm chosen width, depth and accuracy is the implementation of supply chain quality and safety of track power and assurance.

第五篇：HC_SR04超聲波測(cè)距模塊資料

本模塊因生產(chǎn)批次不同有綠色和藍(lán)色，電路和質(zhì)量完全一樣的，如客戶未作特殊要求，我們默認(rèn)發(fā)綠色底板的模塊。

１、本模塊性能穩(wěn)定，測(cè)度距離精確。能和國(guó)外的SRF05,SRF02等超聲波測(cè)距模塊相媲美。模塊高精度，盲區(qū)（2cm）超近,穩(wěn)定的測(cè)距是此產(chǎn)品成功走向市場(chǎng)的有力根據(jù)！2 主要技術(shù)參數(shù)：

1：使用電壓：DC5V2：靜態(tài)電流：小于

2mA3：電平輸出：高5V4：電平輸出：底0V

15度6：探測(cè)距離：2cm-450cm5：感應(yīng)角度：不大于

7:高精度：可達(dá)0.3cm

接線方式，VCC、trig（控制端）、echo（接收端）、GND

本產(chǎn)品使用方法：一個(gè)控制口發(fā)一個(gè)10US以上的高電平,就可以在接收口等待高電平輸出.一有輸出就可以開定時(shí)器計(jì)時(shí),當(dāng)此口變?yōu)榈碗娖綍r(shí)就可以讀定時(shí)器的值,此時(shí)就為此次測(cè)距的時(shí)間,方可算出距離.如此不斷的周期測(cè),就可以達(dá)到你移動(dòng)測(cè)量的值了~~模塊工作原理：

(1)采用IO觸發(fā)測(cè)距，給至少10us的高電平信號(hào);

(2)模塊自動(dòng)發(fā)送8個(gè)40khz的方波，自動(dòng)檢測(cè)是否有信號(hào)返回；

(3)有信號(hào)返回，通過IO輸出一高電平，高電平持續(xù)的時(shí)間就是超聲波從發(fā)射到返回的時(shí)間．測(cè)試距離=(高電平時(shí)間*聲速

(340M/S))/2;