The serious study of the practice of how to determine the appropriate content of a specification is a seldom-appreciated pastime. Those who have the responsibility to design a product would prefer a greater degree of freedom than permitted by the con- tent of a specification. Many of those who would manage those who would design a product would prefer to allocate all of the project funding and schedule to what they consider more productive labor. These are the attitudes, of course, that doom a project to defeat but they are hard to counter no matter how many times repeated by design engineers and managers. A system engineer who has survived a few of these experiences over a long career may retire and forget the past but we have an endur- ing obligation to work toward changing these attitudes while trying to offer younger system engineers a pathway toward a more sure success in requirements analysis and specification publishing.
標(biāo)簽： Requirements Analysis System
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
Recent advances in wireless communication technologies have had a transforma- tive impact on society and have directly contributed to several economic and social aspects of daily life. Increasingly, the untethered exchange of information between devices is becoming a prime requirement for further progress, which is placing an ever greater demand on wireless bandwidth. The ultra wideband (UWB) system marks a major milestone in this progress. Since 2002, when the FCC allowed the unlicensed use of low-power, UWB radio signals in the 3.1–10.6GHz frequency band, there has been significant synergistic advance in this technology at the cir- cuits, architectural and communication systems levels. This technology allows for devices to communicate wirelessly, while coexisting with other users by ensuring that its power density is sufficiently low so that it is perceived as noise to other users.
標(biāo)簽： Circuits Wideband Ultra
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
A wireless ad-hoc network is a wireless network deployed without any infrastructure. In such a network, there is no access point or wireless router to forward messages among the computing devices. Instead, these devices depend on the ad-hoc mode of their wireless net‐ work interface cards to communicate with each other. If the nodes are within the transmis‐ sion range of the wireless signal, they can send messages to each other directly. Otherwise, the nodes in between will forward the messages for them. Thus, each node is both an end system and a router simultaneously.
標(biāo)簽： WIRELESS NETWORKS AD-HOC
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
The purpose of this book is to present detailed fundamental information on a global positioning system (GPS) receiver. Although GPS receivers are popu- larly used in every-day life, their operation principles cannot be easily found in one book. Most other types of receivers process the input signals to obtain the necessary information easily, such as in amplitude modulation (AM) and frequency modulation (FM) radios. In a GPS receiver the signal is processed to obtain the required information, which in turn is used to calculate the user position. Therefore, at least two areas of discipline, receiver technology and navigation scheme, are employed in a GPS receiver. This book covers both areas.
標(biāo)簽： Fundamentals_of_Global_Positionin g_System_Receivers
上傳時(shí)間： 2020-06-09
上傳用戶：shancjb
常用芯片DIP SOT SOIC QFP電阻電容二極管等3D模型庫(kù) 3D視圖封裝庫(kù) STEP后綴三維視圖（154個(gè)）:050-9.STEP0805R.STEP1001-1.STEP1001-2.STEP1001-3.STEP1001-4.STEP1001-5.STEP1001-6.STEP1001-7.STEP1001-8.STEP103_1KV.STEP10X5JT.STEP1206R.STEP13PX2.STEP15PX2.STEP20P插針.STEP25V1000UF.STEP3296W.STEP35V2200UF.STEP3mmLED.STEP3mmLEDH.STEP3X3可調(diào)電阻.STEP400V0.1UF.STEP455.STEP630V0.1UF.STEP7805.STEP8P4R.STEPAXIAL-0.2-0.125W.STEPAXIAL-0.4-0.25W.STEPaxial-0.6-2W.STEPB-3528.STEPC-0805.STEPC06x18.STEPCAP-6032.STEPCH3.96 X2.STEPCH3.96-3P.STEPD-PAK.STEPDB25.STEPDC-30.STEPDIP14.STEPDIP16.STEPDIP6.STEPDIP8.STEPDO-214AA.STEPDO-214AB.STEPDO-214AC.STEPDO-41.STEPDO-41Z.STEPFMQ.STEPGNR14D.STEPH9700.STEPILI4981.STEPIN4007.STEPIN5408.STEPJP051-6P6C_02.STEPJQC-3F.STEPJS-1132-10.STEPJS-1132-11.STEPJS-1132-12.STEPJS-1132-13.STEPJS-1132-14.STEPJS-1132-15.STEPJS-1132-2.STEPJS-1132-3.STEPJS-1132-4.STEPJS-1132-5.STEPJS-1132-6.STEPJS-1132-7.STEPJS-1132-8.STEPJS-1132-9.STEPJS-1132R-2.STEPJS-1132R-3.STEPJS-1132R-4.STEPJS-1132R-5.STEPJS-1132R-6.STEPJS-1132R-7.STEPJS-1132R-8.STEPJZC-33F.STEPKBP210.STEPKE2108.STEPKF2510 X8.STEPKF301.STEPKF301x3.STEPKSD-9700.STEPLED5_BLUE.STEPLED5_GRE.STEPLED5_RED.STEPLED5_YEL.STEPLFCSP_WQ.STEPLQFP100.STEPLQFP48.STEPMC-146.STEPmolex-22-27-2021.STEPmolex-22-27-2031.STEPmolex-22-27-2041.STEPmolex-22-27-2051.STEPmolex-22-27-2061.STEPmolex-22-27-2071.STEPmolex-22-27-2081.STEPMSOP10.STEPMSOP8.STEPPA0630NOXOX-HA1.STEPPIN10.STEPPIN24.STEPPIN24A.STEPR 0805.STEPR0402.STEPR0603.STEPR0805.STEPR1206.STEPRA-15.STEPRA-20.STEPRS808.STEPSIP-3-3.96 22-27-2031.STEPSL-B.STEPSL-D.STEPSL-E.STEPSL-G.STEPSL-H.STEPSOD-123.STEPSOD-323.STEPSOD-523.STEPSOD-723.STEPSOD-80.STEPSOIC-8.STEPSOP-4.STEPSOP14.STEPSOP16.STEPSOP18.STEPSOT-89.STEPSOT223.STEPSOT23-3.STEPSOT23-5.STEPSSOP28.STEPTAJ-A.STEPTAJ-B.STEPTAJ-C.STEPTAJ-D.STEPTAJ-E.STEPTAJ-R.STEPTHB6064H.STEPTO-126.STEPTO-126X.STEPTO-220.STEPTO-247.STEPTO-252-3L.STEPTOSHIBA_11-4C1.STEPTSSOP-8.STEPTSSOP14-BOTTON.STEPTSSOP14.STEPTSSOP28.STEPUSB-A.STEPUSB-B.STEPWT.STEP
標(biāo)簽： 芯片 dip sot soic qfp 電阻 電容 二極管 封裝
上傳時(shí)間： 2021-11-21
上傳用戶：XuVshu
數(shù)字化電源的特點(diǎn)：1.控制智能化它是以數(shù)字信號(hào)處理器(DSP)或微控制器(MCU)為核心，將數(shù)字電源驅(qū)動(dòng)器及PWM控制器作為控制對(duì)象而構(gòu)成的智能化開關(guān)電源系統(tǒng)。傳統(tǒng)的由微控制器控制的開關(guān)電源，一般只是控制電源的啟動(dòng)和關(guān)斷，并非真正意義的數(shù)字電源。2.數(shù)模組件組合優(yōu)化采用“整合數(shù)字電源”(Fusion Digital Power)技術(shù)，實(shí)現(xiàn)了開關(guān)電源中模擬組件與數(shù)字組件的優(yōu)化組合。例如，功率級(jí)所用的模擬組件MOSFET驅(qū)動(dòng)器，可以很方便地與數(shù)字電源控制器相連并實(shí)現(xiàn)各種保護(hù)及偏置電源管理，而PWM控制器也屬于數(shù)控模擬芯片。3.集成度高實(shí)現(xiàn)了電源系統(tǒng)單片集成化(Power System on Chip)，將大量的分立式元器件整合到一個(gè)芯片或一組芯片中。4.控制精度高能充分發(fā)揮數(shù)字信號(hào)處理器及微控制器的優(yōu)勢(shì)，使所設(shè)計(jì)的數(shù)字電源達(dá)到高技術(shù)指標(biāo)。例如，其脈寬調(diào)制(PWM)分辨力可達(dá)150ps(10~12s)的水平，這是傳統(tǒng)開關(guān)電源所望塵莫及的。數(shù)字電源還能實(shí)現(xiàn)多相位控制、非線性控制、負(fù)載均流以及故障預(yù)測(cè)等功能，為研制綠色節(jié)能型開關(guān)電源提供了便利條件。5.模塊化程度高數(shù)字電源模塊化程度高，各模塊之間可以方便地實(shí)現(xiàn)有機(jī)融合，便于構(gòu)成分布式數(shù)字電源系統(tǒng)，提高電源系統(tǒng)的可靠性。
標(biāo)簽： 全數(shù)字電源
上傳時(shí)間： 2021-12-13
上傳用戶：XuVshu
SD卡 USB VGA DB9 RJ45 RJ22 通訊接口封裝Altium Designer AD PCB封裝庫(kù)2D3D元件庫(kù)文件PCB Library : 通訊接口.PcbLibDate : 2020/12/29Time : 14:31:34Component Count : 46Component Name-----------------------------------------------BM4-M003-BBM4-M003-BKBM4-M003-GBM4-M003-RBM4-M003-YDB9/P_ADB9/S_AMicro SDMICRO SIMMICRO SIM-BNano-SIM-ARJ-45A12RJ11-4P4C-LI-BKRJ11-4P4C-LI-GYRJ11-6P6C-BKRJ11-6P6C-GYRJ45_180RJ45-2RJ45-2LEDTF-1USB_A/P_AUSB_A/P_BUSB A/2-14USB A/2-17USB Type-C-6Pin_AUSB Type-C-16Pin_AUSB Type-C-24Pin_AUSB-A/S_AUSB-A/S_BUSB-A/S_CUSB-A/S_DUSB-A/S_EUSB-A/S_FUSB-B/S_AUSB-C/S_AUSB-C/S_BUSB-C/S_CUSB-micro_AUSB-MICRO_BUSB-micro_CUSB-MICRO_DUSB-MICRO_EUSB-MICRO_FUSB-MINI-AVGA15AVGA15B
上傳時(shí)間： 2022-03-12
上傳用戶：得之我幸78
基于藥物治療在臨床治療中的重要性,分析目前服藥提醒裝置存在的不足,以STM32F103VET6單片機(jī)為控制核心,設(shè)計(jì)了一種多功能電子藥箱。該系統(tǒng)包括顯示模塊、語音模塊和數(shù)據(jù)存儲(chǔ)模塊。顯示模塊通過觸摸屏電路和LED指示燈電路,與語音模塊相配合,實(shí)現(xiàn)了服藥提醒及指導(dǎo)的功能;數(shù)據(jù)存儲(chǔ)模塊通過EEPROM存儲(chǔ)電路,能夠?qū)崿F(xiàn)掉電時(shí)服藥信息不丟失的功能。并且為了實(shí)現(xiàn)電子藥箱的智能化控制,開發(fā)了手機(jī)APP,兩者之間可通過WIFI進(jìn)行數(shù)據(jù)通信。經(jīng)測(cè)試,該藥箱能夠有效地幫助慢性病患者按時(shí)、定量、正確服用藥物,適合在家庭中推廣使用,具有較高的應(yīng)用價(jià)值和實(shí)踐意義。Based on the importance of drug therapy in clinical treatment, this paper analyzes the shortcomings of current drug reminder devices, and designs a multi-function electronic medicine box with STM32 F103 VET6 microcontroller as the control core. The system includes a display module, a voice module, and a data storage module. The display module cooperates with the voice module through the touch screen circuit and the LED indicator circuit to realize the function of reminding and guiding the medicine;the data storage module can realize the function of not losing the medication information when the power is off through the EEPROM storage circuit.After testing, the medicine box can effectively help chronic diseases patients to take drugs on time, in a quantitative and correct manner,and is suitable for popularization in the family, and has high application value and practical significance.
標(biāo)簽： 電子藥箱
上傳時(shí)間： 2022-03-27
上傳用戶：
隨著科技發(fā)展及工業(yè)4.0 進(jìn)程推進(jìn),機(jī)械臂應(yīng)用范圍越來越廣,并演化出各種各樣的機(jī)械臂,如碼垛機(jī)械臂、焊接機(jī)械臂、裝配機(jī)械臂以及手術(shù)機(jī)械臂等。現(xiàn)利用solidworks 進(jìn)行三維建模,設(shè)計(jì)制作一款基于stm32f103c8t6 單片機(jī)的主從式桌面級(jí)機(jī)械臂,該機(jī)械臂包括一個(gè)主動(dòng)機(jī)械臂和一個(gè)從動(dòng)機(jī)械臂,采用藍(lán)牙傳輸信號(hào)方式進(jìn)行同步運(yùn)動(dòng),并且詳細(xì)介紹了該機(jī)械臂材料選擇、結(jié)構(gòu)設(shè)計(jì)、工作原理、組成部分和設(shè)計(jì)特點(diǎn)。With the development of science and technology and the advancement of Industry 4.0, the application range of the mechanical arm has become wider and wider, and various types of mechanical arms, such as palletizing robot arms, welding robot arms, assembly robot arms, and surgical robot arms, have been developed. Now using solidworks for 3D modeling, design and manufacture a master-slave desktop-level robot arm based on stm32f103c8t6 single-chip microcomputer. The robot arm includes an active robot arm and a slave robot arm, which uses Bluetooth to transmit signals for synchronous motion. The material selection, structural design, working principle, components and design features of the manipulator are introduced.
標(biāo)簽： stm32f103c8t6 單片機(jī)
上傳時(shí)間： 2022-03-27
上傳用戶：
入室搶劫事件屢見不鮮,針對(duì)此現(xiàn)象進(jìn)行分析不難發(fā)現(xiàn),造成失竊事件的極大原因是人們慵懶和意識(shí)差等不良性格造成習(xí)慣性不鎖門.本文以STC89C52單片機(jī)為基礎(chǔ),設(shè)計(jì)了一種基于人體紅外傳感器的自動(dòng)關(guān)門鎖門裝置,來解決此類問題.The incidents of burglary are so common. It is not difficult to find that the main reason for the burglary is the habit of unlocking of doors caused by people's laziness and poor consciousness. Based on the single chip microcomputer of STC89C52, a device used with infrared sensor of human body is introduced in this paper, which can achieve the effect of automatic closing and locking doors.
上傳時(shí)間： 2022-03-27
上傳用戶：canderile
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