Two-dimensional packing problems A survey

合集下载

ISO包装标准(ISO packing standards)

IEC 60264-3-3-1990
绕组线的包装第 3 部分: Packaging of winding wires; part 3: taper
圆锥形筒装交货线盘第 barrelled delivery spools; section 3:
3 节:热塑性材料不可回 specification for non-returnable spools
IEC 60286-5-2003
自动装配用元件的包装. Packaging of components for automatic 第 5 部分:矩阵式料盘 handling - Part 5: Matrix trays
IEC 60286-6-2004
自动化处理用组件的包 Packaging of components for automatic
IEC 60286-2-1997
自动装配用元件的包装第 2 部分:具有单向引线的元件在连续编带上的带式包装
Packaging of components for automatic handling - Part 2: Tape packaging of components with unidirectional leads on continuous tapes
装.第 6 部分:表面安装组 handling - Part 6: Bulk case packaging for
件的散装箱包装
surface mounting components
IEC 60512-11-13-2002
电子设备连接器.试验和 Connectors for electronic equipment -
1 节:基本尺寸
section one; basic dimensions

儿童智能手表入门指南

儿童智能手表入门指南QuickStart Guide Children's Smartwatch请您在使用之前认真阅读智能手表使用说明书，以便正确安装和快速使用，产品颜色请以实物为准Please carefully read the instructions of the smartwatch before use, so as to install and use it in a correct and easy manner. The color is subject to the actual product!一.产品快速使用说明：I.QuickStart Guide:1:打开电池盖，装入SIM卡小卡（移动或联通卡）并开通来电显示功能和包月流量（建议选择30M/月流量）1.Remove the battery cover, install a small SIM card (China Mobile or China Unicom)and activate the Caller Identification function and subscribe to a monthly traffic package (the 30M/month package is recommended).2：再装回电池，盖上电池盖，扭上螺钉。

2.Install the battery, put on the cover, and then tighten the screws.3：按开关机键开机，听到铃声后松手，屏幕会显示内容即设备进入开机状态。

（设置好主监护号码后手表无法关机，只能在APP或PC端远程关机）3.Press and hold the ON/OFF key until a ringtone is heard, and a message indicatingthat the watch is being started up is displayed on the screen. The watch cannot be powered off locally after the major guardian's number is set. To power it off, use the mobile APP or PC.4：手机端下载app(在说明书尾页会有相应的二维码扫描下载），并登陆。

PLJ-8LED-C 8位频率计用户手册说明书

8-digit LED Frequency Counter ModuleModel PLJ-8LED-CUser Manual V 1.0May 2014Appendix with test details and schematics and additional notes in themain text of this manual were added in August 2016 by ZL2PD.Information including Links and Code (Software) Supplied or Referenced in this Document is supplied by MPJA inc. as a service to our customers and accuracy or usefulness is not guaranteed nor is it an Endorsement of any particular part, supplier or manufacturer. Use of information and suitability for any application is at users own discretion and user assumes all risk.All rights are retained by the Owners/Author(s)34112-TEContents (2)Overview (2)Technical Specifications (3)Operation and Use (5)Product Ordering (9)FAQ (10)About DIY (11)Appendix : Testing and Modifications (12)The PLJ-8LED-C module is a cost-effective 8-digit frequency counter and display module primarily to display the operating frequency in a transceiver and other equipment. It may also be used for conventional frequency measurement. The module offers compact, reliable high performance with clear display at low cost.The main features include:∙Microchip PIC16F648A forms the core of the 2.4GHz frequency meter.∙Frequency reference using a temperature-compensated voltage controlled crystal oscillator(2.5 ppm VC-TCXO).∙Unique gate control with precise time algorithm (No timer interrupt).∙Gate (display refresh) times include 0.01, 0.1 and 1.0 seconds to allow a real-time frequency display.∙Single connector input design supports three frequency measurement modes (Low channel / High channel / Auto mode).∙Dual mode IF modes allow the offset value and the IF up / down mode to be separately preset.∙Eight 0.56 inch high brightness LED digits with adjustable brightness.∙Automatic leading zero blanking, invalid display filter frequency selectable, optional last bit blanking.∙Elegant circuit design supports two-button control for simple operation.∙Settings are saved automatically and directly recalled at power-up.1.GATE TIME∙0.01 sec∙0.10 sec∙ 1.0 sec2.CHANNEL MEASUREMENT PERFORMANCE (CHANNEL LEVEL HIGH IMPEDANCE)Low channelMeasuring range: 0.1 MHz - 60 MHzAccuracy: ± 100Hz (0.01 sec gate time)± 10Hz (0.1 sec gate time)± 1Hz (1.0 sec gate time)Low channel sensitivity:0.1 MHz - 10 MHz: Better than 60mVpp10 MHz - 60 MHz: Better than 60mVpp60 MHz - 75 MHz: Not specifiedHigh channel (Divide by 64)Measuring range: 20 MHz - 2.4 GHzAccuracy: ± 6400Hz (0.01 sec gate time)± 640Hz (0.1 sec gate time)± 64Hz (1.0 sec gate time)High channel sensitivity:20 MHz - 30 MHz: Better than 100mVpp30 MHz - 60 MHz: Better than 50mVpp60 MHz - 2.4GHz: Not specifiedAuto ChannelDepending on the frequency of the input signal, the counter will automatically select thehigh or low channel (Change occurs at 60 MHz). If the input signal is greater than 60 MHz buta weak signal level prevents automatic high channel selection, it is possible to manuallyselect the high frequency channel.3.IF SETTINGSIndependent double-IF design allows the IF settings to be adjusted in minimum increments of 100 Hz.∙Intermediate frequency range:0 - 99.9999 MHz∙Offset:Plus or minus IF mode can be configured4.FREQUENCY REFERENCE13.000MHz temperature compensated voltage controlled crystal oscillator (VC-TCXO) in 5032 package ∙Frequency stability: ± 2.5 ppm5.SUPPLYDC Input: 9V - 15V (Reverse polarity protection)Current: 160 mA max (Test conditions: 12VDC supply, red LED display, brightness=8)6.DISPLAYReadout: Eight 7-segment LED digits.Brightness: Eight LED brightness levels, factory set to maximum brightness.7.PHYSICALDimensions (L×W×H): 125.5 mm × 25.5 mm × 21.5 mmWeight: 46 g (net weight)8.INTERFACESDC IN (Power Interface): HX2.54-2P socketRF IN (signal input): HX2.54-2P socketICSP (programming interface): 2.54-6P Pin1.MODULE ARRANGEMENTFront view of moduleDC In TCXO cal Program Input sensitivity (H/L) RF InRear view of moduleNote: This diagram shows the High channel (Ch H) components on the right hand end of the board. The Low channel components are located on the other side of the PCB under the LED display.2.MOUNTING DIMENSIONSING THE MODULE1.Please check the power supply voltage (DC 9V-15V) and confirm the power supply polarity before use. The power supply circuit in the module has a series diode fitted to prevent operation when the power supply is inadvertently connected with reverse polarity. This protects the module from devastating consequences.2.The signal input (2-pin) port may be connected directly to the measured signal (wired) or to an antenna (inductive mode).SYSTEM SETTINGSRed: display characterBlue: blinking characterGATE TIME ADJUSTMENTSYSTEM RESETOne of two IF frequencies may be selected by using pin 4 of the ICSP programming interface. If pin 4 is pulled High or left floating, then the first IF frequency is used. If pin 4 is pulled to ground, then the second IF frequency is selected.Each IF frequency can be independently programmed with IF frequency and offset (Add or subtract). The first IF settings are programmed when pin 4 is pulled High or left floating, and. the second IF settings are programmed when pin 4 is pulled to ground.The default factory programming sets the floating pin 4 as the first IF configuration. If the IF is zero, then the Up/Down setting is ignored.In practice, pin 3 (GND) and pin 4 of the ICSP programming interface ICSP can be connected to a 2P DuPont connector immediately adjacent or on the pins (See location circled in red below). A switch can then be connected to select the appropriate IF setting.(C) MEASURING FREQUENCIESThe signal to be measured should be connected to the RF IN (signal input) port. This signal input can be connected to the local oscillator output from a transceiver or to other test points. Once connected, the LED display will show the frequency in real time.The high-impedance input design helps to reduce the load of the counter on the local oscillator circuit in the transceiver LO. However, the signal being measured should be greater than 60mVpp. For example, the oscillator signal from the widely used NE602 / NE612 is weak and the counter may not be able to obtain a stable frequency value.To facilitate the use of test equipment, Sanjian Studios can supply small quantities for personal purchases. Agents should go to the main page of the Taobao search engine and search for "Sanjian Studio" or "PLJ-8LED" or they can also directly contact the company.The product packaging bag is sealed with a label containing a two-dimensional barcode. This may be scanned to load a web address to obtain product-related technical support.PRODUCT DETAILS:∙IC devices installed∙Reflow process used∙Uses double sided plated through nickel-plated copper PCB∙No power supply, no enclosure∙Fully testedPACKING LIST:∙PLJ-8LED-C module (in anti-static bag) 1 off∙XH2.54-2P 20cm long cable 2 offPRECAUTIONS:∙Two XH2.54-2P 20cm cables are included in the package. Please note the color polarity and connect correctly. Check the wiring polarity of the socket assembly before applying power,and read the manual before using the module to understand its operation.∙Do not place the instrument in hot, humid, or dusty environments, and mountings should prevent severe vibration.∙After module manufacturing, the reference frequency oscillator was aligned using a rubidium reference. The sensitivity adjustment has been optimized so do not adjust unless necessary.∙Under normal usage, the module is covered by a warranty period of six months. Warranty does not apply if subjected to incorrect use, modifications, or operated under abnormalconditions which may lead to the destruction of the product.1.Will the frequency counter generate any interference when installed in a transceiver?Zero interference is impossible because the microcontroller, crystal and LED driver all produce some radiated RF noise, but the level is quite low. Some measures have been taken in the design of the module to keep certain components away from the transceiver. If interference is encountered, try changing the position of the module or install a shield.2.What is the reason for frequency display instability?First, make sure the quality (strength, stability, etc.) of the input signal meets the minimum requirements of the module (see Technical Data section). The input cable connecting to the signal should use shielded wire, and the power supply should also be suitable. Check it has no noise or ripple.3.Why is the display showing values when there is no input signal?Check if the ripple on the power supply being used with the module is too large, then check whether if something near the module is generating a strong signal. The module can reject invalid signals by using signal filtering. On the low range (CH L), filtering removes invalid signals below 50kHz, and below 20MHz on the high range (CH H). This will then result in the normal display showing zero with no input signal.4.Since the display is limited to eight digits, how can it display the “hundreds of megahertz” and gigahertz digits with 0.1s and 1s gate times?By reducing the gate time or using the LSD function, it is possible to obtain a suitable frequency display.For example, when measuring 450.000 000 MHz signal:When the LSD is OFF (See Menu setup section above)∙1S gate display:50.000.000∙0.1S gate display:450.000.00When the LSD is ON∙1S gate display:450.000.00∙0.1S gate display:450.000.0When measuring a 2400.000 000 MHz signal:When the LSD is OFF∙1S gate display:00.000.000∙0.1S gate display:400.000.00When the LSD is ON∙1S gate display:400.000.00∙0.1S gate display:2400.000.0A full set of manufacturing information on the PLJ-8LED-C was released on a forum which can be sent directly to a PCB Gerber file processing plant. The software is also available (as a HEX file) suitable for most microprocessor programmers without manual intervention. If your programmer doesn’t recognize the settings, the crystal type can be selected and the remaining options simply turned off. (Note: Sites appear to require registration)A summary of all the conditions covering this software and which limits its use are found in the programming document released by the Forum. When you power on the 25th time, the counter will display "--------". To remove these restrictions and continue to use the counter, carry out a system reset to recover (Press and hold the SET key during boot up). There are no other hardware or software traps.Attachments containing the frequency meter data for previous releases can be found on the forum, as follows:2008-11-03：/forum/read.php?tid=1895832008-11-04：/forum/read.php?tid=1896962008-11-05：/forum/read.php?tid=1897182009-03-30：/forum/read.php?tid=2008682011-04-27：/forum/read.php?tid=2644172011-12-14：/forum/read.php?tid=2826262013-03-22：/forum/read.php?tid=312288All intellectual property rights contained in this product are the property of Sanjian Studio. The information published can be copied or reprinted, and (we) encourage individuals to copy and test this design, but not for commercial purposes.Copyright notice from original manual:© 2008 Sanjian Studio 三剑工作室E-mail：************* QQ：307693659Note: Additional details and the following appendix have been added to this translation from various sources and attributed where the source is known.1.ACCURACYThe accuracy of the measured frequency was tested by F6CQK using an EPOC quartz oscillator calibrated from a rubidium clock. This showed an error of -10 Hz. This was easily corrected using the calibration adjustment available near the TCXO.A measurement over 24 hours shows a stability better than 1 Hz.2.SENSITIVITYThe sensitivity of the module was measured by F6KEH, shown below:Low Channel (CH L)High Channel (CH H)3.SCHEMATIC AND MODIFICATIONSIt is noted that the UHF channel allows measurements up to about 450 MHz. This path comprises a divide by 64 stage claimed to be able to operate to 2.4GHz according to the published specifications. It is therefore surprising that the sensitivity fell as quickly as it did. The problem could come from the automatic channel switching. Unfortunately no schematic is provided in the Chinese instructions.However, elsewhere, a circuit for the front end was located:This shows a conventional preamplifier for each channel paralleled at the input, each channel using a dual gate MOSFET as a preamplifier followed by a buffer stage (CH L) or divider/buffer (CH H). The buffer transistors in each channel are used to obtain a TTL level. This somewhat “agricultural” approach suggests that the low channel is likely to be excessively loading the higher channel, and that is precisely what we see in the French sensitivity results.The ideal solution to this is to separate out the two inputs and connect them to two separate input connectors, one for each channel.Note: The High channel (including prescaler) is located on the visible side of the PCB adjacent to the PIC microprocessor and the TM1639 LED display driver. The Low channel is not visible. It is located under the left hand front panel LED display (when the module is viewed from the front) and is connected to the input connector and microcontroller via through-plated holes in the PCB.4.CHANNEL SWITCHING RELIABILITYThe manual notes (See above) that the automatic channel switching does not always work reliably for low frequencies above 30 MHz. In this case it is best to manually select the range.For frequencies above 100 MHz, the hundreds digit may not be displayed sometimes. In this case, press the Δ button to select the appropriate gate time until the hundreds digit is displayed.。

北京市海淀区2024届高三下学期期中练习(一模)英语试卷

海淀区2023-2024学年第二学期期中练习高三英语2024. 04本试卷共10页，100分。

考试时长90分钟。

第一部分知识运用（共两节，30分）第一节（共10小题；每小题1. 5分，共15分）阅读下面短文，掌握其大意，从每题所给的A、B、C、D四个选项中，选出最佳选项，并在答题卡上将该项涂黑。

It was 4: 30 pm. As I was packing up, I noticed my colleague had left his laptop bag in the office. So I decided to bring it to him. It took me about 15 minutes to get to his house, where I 1 the bag and got right back on the road.Suddenly a snowstorm came and within minutes I was in a whiteout. I stopped because I was afraid of driving into a farmer's field, or worse. I kept the car 2 to stay warm and called 911. They told me to sit tight and wait things out for the night.Those seconds after the call were 3 . Breathe, I told myself. Panicking won't help.I texted my colleague, joking about my good deed ending in 4 . He suggested I share a satellite view of my 5 on my social media. And I did so, praying that anyone who knew the residents of the nearby farms could get me rescued.Waiting in the car, I doubted whether 6 would be able to come. Soon enough, though, I got a message from someone who was going to put me in touch with them.At 8 pm, I saw a tall figure in a yellow raincoat striding toward me in the dark, carrying a flashlight. I'd never been more 7 to see someone in my life. It was André Bouvier, who'd walked about 550 yards to come get me, fighting the wind and snow each step of the way.He turned around and started to trudge through the snow, sure of the direction. I drove behind him, feeling my heart begin to beat more 8 . When we reached his house, I burst into tears, all my fears turning into relief and 9 .The experience has been a game changer for me. I now 10 challenges with a sense of calm I'd not known before. But best of all, it brought André into my life.1. A. dropped off B. filled up C. set aside D. put away2. A. locked B. parked C. signaling D. running3. A. painful B. critical C. disappointing D. impressive4. A. failure B. smoke C. disaster D. mystery5. A. route B. location C. direction D. destination6. A. news B. help C. hope D. faith7. A. satisfied B. surprised C. relieved D. worried8. A. slowly B. excitedly C. nervously D. strongly9. A. recognition B. admiration C. satisfaction D. appreciation10. A. identify B. present C. approach D. anticipate第二节（共10小题；每小题1. 5分，共15分）阅读下列短文，根据短文内容填空。

求解长方体Packing问题的捆绑穴度算法

求解长方体Packing问题的捆绑穴度算法何琨;黄文奇【期刊名称】《软件学报》【年(卷),期】2011(22)5【摘要】Based on the caving degree method, this paper proposes a heuristic approach to solve the cuboid packing problem by incorporating the cuboid arrangement strategy.Experiments on 15 classic LN benchmark instances, performed by Lob and Nee in 1992, have shown that this approach has the potential of performing very well.In the difficult instance of LN2, it achieved a volume utilization of 98.2％, which is an improvement from the current best record by 1.6％.In another difficult instance of LN6, it achieved a volume utilization of 96.2％, which matches that of the current best record.For each of the other 13 instances, it maintains optimal layout that packs all euboid items into the container, matching current best record.As a whole, the average volume utilization on the 15 LN instances is 70.96％.%在穴度方法的基础上结合捆绑策略,为三维欧氏空间中长方体Packing 问题的求解提供了一种高效的启发式算法.试算了由Loh和Nee于1992年提出的15个经典算例,对其中的困难算例LN2,取得了98.2%的空间利用率,比目前的最好纪录高1.6个百分点;对另一个困难算例LN6,取得了96.2%的空间利用率,与目前的最好纪录持平;对其他13个较为容易的算例均取得了最优的布局,与目前的最好纪录持平.总体而言,15个算例的平均空间利用率为70.96%,在整体空间利用率上达到了较好的效果.【总页数】9页(P843-851)【作者】何琨;黄文奇【作者单位】华中科技大学,计算机科学与技术学院,湖北,武汉,430074;华中科技大学,计算机科学与技术学院,湖北,武汉,430074【正文语种】中文【中图分类】TP301【相关文献】1.一种求解二维矩形Packing问题的拟人型全局优化算法 [J], 邓见凯;王磊;尹爱华2.求解长方体Packing问题的高效算法 [J], 何琨;黄文奇3.求解一刀切式二维矩形Strip Packing问题的混合搜索算法 [J], 郭超;王磊;尹爱华4.一种求解等圆Packing问题的柔性位置选择算法 [J], 王英聪;张领;肖人彬5.求解长方体packing问题的拟人算法 [J], 黄文奇;赵亮因版权原因，仅展示原文概要，查看原文内容请购买。

石墨烯复合材料的制备、表征及性能

石墨烯复合材料的制备、表征及性能郝丽娜【摘要】石墨烯属于一种二维晶体结构,它是由碳原子紧密堆积而成,其中有富勤烯、石墨以及碳纳米管等基本单元,这些都是碳的同位异形体.石墨烯在力学领域、电学领域、热学领域以及光学领域等都发挥出其优越的性能,因此,这一复合材料在当今已经成为了科学领域和物理学领域之中研究的焦点.对石墨烯复合材料的制备、表征以及性能进行分析,希望可以对石墨烯的应用与研究起到一定的帮助.%Graphene belongs to a two-dimensional crystal structure,which is formed by the close packing of carbon atoms.There are basic units such as rich olefins,graphite and carbon nanotubes,which are allomorphs of carbon.Graphene has exerted its superior performance in various fields such as mechanics,electricity,heat,and optics.Therefore,this composite material has become the focus of research in the fields of science and physics.This paper is to analyze the preparation,characterization and performance of graphene composites,and hope to help the applicationand research of graphene.【期刊名称】《化工设计通讯》【年(卷),期】2019(045)009【总页数】2页(P128-129)【关键词】石墨烯复合材料;制备;表征;性能【作者】郝丽娜【作者单位】齐齐哈尔工程学院,黑龙江齐齐哈尔 161005【正文语种】中文【中图分类】TB332 ;TM53因为石墨烯所具有的二维晶体结构是比较特殊的，所以其纵横比很高、电子迁移率也很高，这就使得石墨烯在储能领域之中的应用前景十分广泛。

立体化思考英文

立体化思考英文Embracing the Third Dimension: The Power of Spatial ThinkingHumanity's journey of intellectual evolution has been marked by a constant pursuit of new perspectives and innovative ways of understanding the world around us. One such transformative approach is the concept of spatial thinking, which encourages us to move beyond the confines of linear, two-dimensional reasoning and embrace the richness of the three-dimensional realm.At the heart of spatial thinking lies the recognition that our universe is inherently multidimensional. From the intricate structures of atoms and molecules to the grand celestial bodies that dot the cosmos, the world we inhabit is imbued with depth, texture, and a profound sense of interconnectedness. By cultivating the ability to visualize and comprehend these three-dimensional relationships, we unlock a powerful tool for problem-solving, creative expression, and a deeper understanding of the natural and man-made environments we navigate.One of the primary benefits of spatial thinking is its capacity to enhance our problem-solving abilities. When faced with complexchallenges, the traditional linear approach often falls short, as it fails to account for the multifaceted nature of the problem at hand. In contrast, spatial thinking encourages us to consider the problem from multiple angles, to identify patterns and relationships that may not be immediately apparent, and to devise innovative solutions that leverage the inherent complexity of the situation.Consider, for instance, the field of architecture. Architects who embrace spatial thinking are able to envision the three-dimensional flow of a building, anticipating how people will navigate the space, how light and shadow will play across the surfaces, and how the structure will integrate with its surrounding landscape. This holistic understanding allows them to create designs that are not only aesthetically pleasing but also highly functional, catering to the diverse needs and experiences of the building's occupants.Similarly, in the realm of scientific research, spatial thinking has proven invaluable. Researchers studying the intricate structures of molecules, the dynamics of fluid flow, or the intricacies of the human body rely on their ability to visualize and manipulate three-dimensional models to uncover groundbreaking insights and develop cutting-edge technologies. By moving beyond the confines of two-dimensional representations, these scientists are able to identify subtle nuances, explore alternative scenarios, and push the boundaries of their respective fields.The benefits of spatial thinking extend far beyond the realms of architecture and science. In the arts, painters, sculptors, and designers harness the power of three-dimensional visualization to create works that captivate the senses and evoke profound emotional responses. Musicians, too, leverage spatial thinking in their compositions, considering the interplay of sound waves, the placement of instruments, and the immersive experience of the audience.Even in our everyday lives, spatial thinking plays a crucial role. From navigating the complexities of urban environments to packing our belongings efficiently, our ability to envision and manipulate three-dimensional spaces allows us to make informed decisions, optimize our actions, and enhance our overall quality of life.However, the true transformative power of spatial thinking lies in its capacity to shape our fundamental worldview. By embracing a multidimensional perspective, we begin to see the world not as a collection of isolated, two-dimensional entities, but as a dynamic, interconnected tapestry of relationships and possibilities. This shift in mindset can have profound implications, from the way we approach problem-solving to the manner in which we engage with our communities and the natural world.As we navigate the rapidly evolving landscape of the 21st century, the need for spatial thinking has become increasingly pressing. The complex challenges we face, from climate change to social inequity, demand a holistic, multidimensional approach that transcends the limitations of linear thinking. By cultivating and nurturing our spatial intelligence, we can unlock new avenues for innovation, collaboration, and the creation of a more sustainable, equitable, and fulfilling future.In conclusion, the power of spatial thinking lies in its ability to expand our horizons, challenge our assumptions, and unlock new realms of possibility. By embracing the third dimension and the richness of multidimensional relationships, we can transform the way we perceive, interact with, and shape the world around us. As we continue to push the boundaries of our understanding, the promise of spatial thinking remains a beacon, guiding us towards a future where the limitations of the past give way to the boundless potential of the present and the yet-to-be-discovered.。

展会常用英语词汇中英文解读

香港展会PCB专业术语（中英文）1.线路板生产流程：• 板材(board：硬板 rigid board、环氧玻璃纤维板(FR-4 Epoxy glass fiber board-type4 双面板 double layers board 多层板 Multi-layers board• 开料(board cut：来料检查material incoming inspection、剪板 material-cutting磨边Milling、洗板 board washing、烤板 board baking• 内层线路inner circuit：前处理pretreat、压干膜dry film pressing、对位registration 曝光exposed、显影development、蚀刻etching、品质控制（QC） quality control • 层压：lamination-pressing• 钻孔 drilling• 沉铜 (PTH plated through hole• 外层线路outer circuit• 外层蚀刻：outer etching• 阻焊 soldermask• 字符 legends• 表面处理surface finishing：沉金(ENIGElectroless nickel immersion gold沉银immersion silver 沉锡 immersion Tin；有铅喷锡(HALHot air leveling无铅喷锡Lead-free hot air leveling 抗氧化(OSPOrganic Solderability Preservatives；电金gold-plating；金手指 gold finger• 成型routing：冲压pounching、楔形掏槽（V-cut）wedge cut• 电测试(E-test electronic test：飞针probeflying, 测试架fixture• 终检（FQC）final quality control• 包装packing2.其他相关术语a.金厚测试仪gold thickness tester 阻抗测试仪impedance tester拉力测试仪Tension measuring instrument 二次元测试仪 Two dimensional tester b.通孔Vias、过孔via hole 埋孔buried holes、盲孔blind holes 定位孔tooling holes 半固化片（PP）prepregc.拼板panel、工艺边tooling edge、干膜dry film、菲林filmd.尺寸size、样板sample、批量mass production、交期lead time、产能production capacitye.板厚board thickness、铜厚copper thickness、公差tolerancef.线宽line width、线距line space、孔径hole size。

2022年考研考博-考博英语-厦门大学考试全真模拟全知识点汇编押题第五期(含答案)试卷号：33

2022年考研考博-考博英语-厦门大学考试全真模拟全知识点汇编押题第五期（含答案）一.综合题(共15题)1.单选题The captain performs his duties with great_______and all the crew believed that they can get over the storm.问题1选项A.affectionB.suspicionC.assuranceD.definition【答案】C【解析】affection喜爱, 影响; suspicion怀疑; assurance确信, 断言, with assurance指有把握地, 自信地; definition定义。

句意：船长信心十足地履行着他的职责，所有的船员都相信他们能够战胜暴风雨。

选项C符合句意。

2.单选题To give you a general idea of our products, we enclose the catalogues showing various products handled by us with detailed_______and means of packing.问题1选项A.specimensB.inspectionsC.samplesD.specifications【答案】D【解析】specimens样本; inspections视察, 检查; samples样品; specifications规格, 规范。

句意：为了使您对我们的产品有一个大致的了解, 随函附上我方经营的各种产品的目录, 以及详细的规格和包装方法。

选项D更符合句意。

3.单选题Any nation that interferes in the internal affairs of another nation should be_______condemned. 问题1选项A.verballyB.universallyC.wickedlyD.visually【答案】B【解析】verbally口头地；universally普遍地；wickedly恶劣地，居心叵测地；visually视觉地。

HyperStakAPEZStyleDispenserforMicroplates

HyperStak:A PEZ Style Dispenserfor Microplates*Daniel P.Cinicola,1*Justin Webster,2and Paul Skerker1 1Millennium Pharmaceuticals,Cambridge,MA;2HyperTask,Hopkinton,MAH yperStak is a new microplate stacker,which can beintegrated onto most robotic systems without the need for costly software integration.It was developed to minimize the downtime and cost associated with microplate handling errors made by robots within passive microplate stackers and to maximize microplate storage space by decreasing the workspace often required by other microplate stackers.The‘‘when-you-need-it’’design of the HyperStak always has a microplate ready for use,which translates into a reduced robotic access time and an increased overall throughput of the system.(JALA 2005;10:327–30)I NTRODUCTIONTo understand why the HyperStak was developed,it is important to know the diﬀerent options available for microplate automated storage.There are prin-cipally two diﬀerent access modes currently used in the storage of microplates:random access and stacker-based systems.Random access modes usu-ally require either a tray-or a carousel-based storage system.With tray-based storage,each location is designed to handle a number of diﬀerent consumables;in comparison,carousel racks are often designed for speciﬁc consumables.To use diﬀerent consumables within the same carousel, diﬀerent carousel racks,each speciﬁc for a particular consumable,are required.Tray-based systems pro-vide access to a number of items at once,whereas carousel-based systems present a desired consum-able concurrent with a robotic action.Both random access storage devices contain a large number of samples in a comparatively small space,are diﬃcult to manually load and unload,and require a higher level of integrated software control for seamless operation within a robotic system.Stacker-based storage devices provide samples serially to the robotic system and are easy to man-ually load and unload.The passive stacker(i.e.,used by Caliper on Twister/TwisterII and Thermo Electron on Catalyst Express)must be replicated numerous times to increase a robotic system’s storage capacity.This signiﬁcantly increases the footprint of the system.Passive stackers must be arranged appropriately to permit a robot to enter the stacker from the top and reach down to all positions within a stack.This limitation means that these stackers cannot be placed directly in front of one another because this would inhibit the robot from reaching all of the samples within each of the stackers.An advantage of these systems is that little is needed in the way of hardware control of the stacker,because the robot performs all manipula-tions.A common error with this type of stacker occurs when a microplate is knocked out of the robot’s hand during its movements through the stacker.Stacker-based systems that present consum-ables mechanically from the bottom of the stack (i.e.,Tecan TeStack and Velocity11VStack) virtually eliminate the errors associated with micro-plateﬂipping.These bottom-access systems requireKeywords:HyperTask,automated stacker,microplate stacker,HyperStak*PEZ is a registered trademark of the PEZ Candy Company.*Correspondence:Mr Daniel P.Cinicola,M.S.,MillenniumPharmaceuticals,75Sidney St.,Cambridge,MA02139;Phone:þ1.617.679.7241;E-mail:****************1535-5535/$30.00Copyright c2005by The Association for Laboratory Automationdoi:10.1016/j.jala.2005.07.001Technology Reviewsoftware for hardware control and subsequent integration into a robotic system,increasing the cost of this device.The HyperStak is designed to correct a number of issues described here and commonly seen with both the random access and stacker-based systems.First,the HyperStak’s small footprint provides the user with the means of having multiple HyperStaks on a system without using a signiﬁcant amount of workspace.Second,no software integration is required.This provides the opportunity to use HyperStak on most robotic systems without the need for custom software integration.Third,HyperStak is designed with a single access point,which is serviced by a feeding mechanism that minimizes the number of microplateﬂipping errors seen with most passive stackers.This mechanism permits the ‘‘when-you-need-it’’concept allowing the microplate to be waiting in the access position without any instruction from the software controlling the robotic system.Further,the single access point reduces the number of positions to teach in comparison to other robotically accessed stackers.In addition,the HyperStak presents microplates to the robot from the top of the stacker,allowing for dense packing of the storage device and increasing capacity without a signiﬁcant space reduction.M ETHODS AND MATERIALSThe HyperTask HyperStak(Fig.1)consists of two pieces: a removable tower for holding consumables and a motor-driven platform including the base.The base consists ofa programmable logic controllers for controlling movements of the platform,an optical sensor for edge detection of the microplate,and two toggle switches.Theﬁrst toggle allows the user to jog the platform up or down as needed.The second toggle sets the initial operational mode of the HyperStak,which is either the input or output.If an output mode is selected,the platform drives up until the edge detection sensor detects a microplate and then moves a deﬁned distance to place the microplate into position for robotic access.Input mode will move the platform up until either the edge of a microplate or nothing is detected.At this point,the HyperStak prepares to receive microplates from the robot.Once a microplate is detected on the platform, the HyperStak will move down until the top edge of the microplate is detected.At this point it will then await the next incoming microplate.The Thermo Electron Catalyst Express system was used for the HyperStak integration project.The HyperStak was designed to hold39microplates within a16Â17.8Â66cm footprint(see Fig.2)to meet the height requirements of the Thermo robot.Because no external control was required for this device,no software drivers were necessary to control the HyperStak.R ESULTSThe fully automated stacker was installed on the Thermo Electron Catalyst Express system.Because one of the objectives of the HyperStak was its ability to run without any software integration,the HyperStak was fully opera-tional within30min on the ing the Thermo Electron Polara software,the single access point per stack was taught,a method and sequence were generated,and the robot began accessing the stacker.Three different384-well microplate types were initially tested:black polystyrene, white polystyrene,and clear polypropylene.The black polystyrene microplate worked without incident.Both the white polystyrene and clear polypropylene microplates exhibited some initial problems when the stacker was in the output mode.This problem was resolved by correcting a timing-related issue with the optical sensor located at the presentation point.Three hundred clear and white micro-plates were then run without incident.All three microplate types were then intermixed and run without issues.C ONCLUSIONOne of the most important aspects of the HyperStak is its ability to automatically switch between output and input modes.When the HyperStak is running in output mode and the last microplate is removed,the HyperStak will detect the absence of microplate on the platform and automatically switch into input mode and wait for an incoming microplate to be placed onto the platform.This is helpful in allowing multiple stacks to be used on a system.For example,in Figure1.Each of the two HyperTask HyperStakÔstackers shown contains a maximum of39microplates housed in a16Â17.8Â66cm footprint.Technology Reviewa system with three stacks,the second and third stacks may be ﬁlled with microplates and the ﬁrst stack remains empty.The robot can take the microplates from the second stack,perform some operation and then place the microplates into the ﬁrst stack.Once the second stack is empty and the ﬁrst stack is full,the system can pull microplates from the third stack and put them into the second stack.Microplates are presented serially to a single use point at the top of the stacker.The robotic handler can access all the microplates in the stack from this position,which decreases robotic access time and eliminates traversing errors by the robot commonly experienced with most general stacker racks.This design also speeds the teaching of the positions for a robot because only one position needs to be taught per stack to access all the consumables.The HyperStaks were designed to work together with one stacker handing out (output)and the other receiving microplates (input).The 3-s pause built into the logic of the HyperStak provides suﬃcient time for the robot to move clear of the access point before the HyperStak motor-driven platform is engaged.It takes less than 2s for the platform to move into position,which occurs while the robot is moving the previous sample onto its next position.The HyperTask HyperStak successfully achieved the primary project tasks.The HyperStak39,described here,has a capacity of 39microplates.Because it was built around the Society for Biomolecular Screening standard,it is alsocapableFigure 2.The HyperStak is pictured integrated with a Catalyst Express with one being an input position and the others as outputpositions.Figure 3.Four HyperStak towers in a dense pack formation occupy 30Â38cm of workspace.Technology Reviewof working with deepwell and midwell microplates,two-dimensional tube racks,and tip boxes.The rapid,single point accessibility of the stacker combined with its ability to automatically switch between output and input modes makes the integration of this device into a robotic system a simple and worthwhile addition to increase sample capacity and throughput without signiﬁcantly increasing workspace or requiring additional integration cost.The single access point also removes the need to leave access room for a robotic arm to get from the lowest nest position of a stack,thereby permitting dense packing of the units(see Fig.3).In this orientation,which starts with three HyperStaks full of microplates and one empty,90microplates would be available from a30Â38cm space.In the near future,plans for the HyperStak involve a higher level of software control using either RS232or RS485communications via an ActiveX control if desired by the user and adding an adjustable mounting bracket,which would permit the HyperStak to be recessed within a work-table yielding access to the robot at whatever height the user/ integrator might seeﬁt.In this recessed mode,a removable insert has been considered which could aid in the loading and removing of consumables from the HyperStak towers.Recently,the Matrix Trakmate two-dimensional tube racks were successfully run using the HyperStaks,and each tower was capable of holding up to10racks.The Hyper-Stak39and a larger capacity50-microplate unit(Hyper-Stak50)are currently available from HyperTask.Technology Review。

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InvitedReviewTwo-dimensionalpackingproblems:Asurvey

AndreaLodi*,SilvanoMartello,MicheleMonaciDipartimentodiElettronica,InformaticaeSistemistica,UniversityofBologna,VialeRisorgimento2,40136Bologna,ItalyReceived9March2001

AbstractWeconsiderproblemsrequiringtoallocateasetofrectangularitemstolargerrectangularstandardizedunitsbyminimizingthewaste.Intwo-dimensionalbinpackingproblemstheseunitsareﬁniterectangles,andtheobjectiveistopackalltheitemsintotheminimumnumberofunits,whileintwo-dimensionalstrippackingproblemsthereisasinglestandardizedunitofgivenwidth,andtheobjectiveistopackalltheitemswithintheminimumheight.Wediscussmathematicalmodels,andsurveylowerbounds,classicalapproximationalgorithms,recentheuristicandmetaheuristicmethodsandexactenumerativeapproaches.Therelevantspecialcaseswheretheitemshavetobepackedintorowsforminglevelsarealsodiscussedindetail.Ó2002ElsevierScienceB.V.Allrightsreserved.

Keywords:Two-dimensionalpacking;Binpackingproblems;Strippackingproblems

1.IntroductionInseveralindustrialapplicationsoneisrequiredtoallocateasetofrectangularitemstolargerrectangularstandardizedstockunitsbyminimi-zingthewaste.Inwoodorglassindustries,rect-angularcomponentshavetobecutfromlargesheetsofmaterial.Inwarehousingcontexts,goodshavetobeplacedonshelves.Innewspaperspaging,articlesandadvertisementshavetobear-rangedinpages.Intheseapplications,thestan-dardizedstockunitsarerectangles,andacommonobjectivefunctionistopackalltherequesteditems

intotheminimumnumberofunits:theresultingoptimizationproblemsareknowninthelitera-tureastwo-dimensionalbinpackingproblems.Inothercontexts,suchaspaperorclothindustries,wehaveinsteadasinglestandardizedunit(arollofmaterial),andtheobjectiveistoobtaintheitemsbyusingtheminimumrolllength:theprob-lemsarethenreferredtoastwo-dimensionalstrippackingproblems.Aswewillseeinthefollow-ing,thetwoproblemshaveastrictrelationinalmostallalgorithmicapproachestotheirsolu-tion.Mostofthecontributionsintheliteraturearedevotedtothecasewheretheitemstobepackedhaveaﬁxedorientationwithrespecttothestockunit(s),i.e.,oneisnotallowedtorotatethem.Thiscase,whichistheobjectofthepresentarticle,re-ﬂectsanumberofpracticalcontexts,suchasthecuttingofcorrugatedordecoratedmaterial(wood,glass,clothindustries),orthenewspaperspaging.

EuropeanJournalofOperationalResearch141(2002)241–252*Correspondingauthor.Tel.:+39-051-209-3029;fax:+39-

051-209-3073.E-mailaddresses:alodi@deis.unibo.it(A.Lodi),smar-tello@deis.unibo.it(S.Martello),mmonaci@deis.unibo.it(M.Monaci).

0377-2217/02/$-seefrontmatterÓ2002ElsevierScienceB.V.Allrightsreserved.PII:S0377-2217(02)00123-6Forvariantsallowingrotations(usuallyby90°)and/orconstraintsontheitemsplacement(suchasthe‘‘guillotinecuts’’),thereaderisreferredtoLodietal.[41,42],whereathree-ﬁeldclassiﬁcationoftheareaisalsointroduced.GeneralsurveysoncuttingandpackingproblemscanbefoundinDyckhoﬀandFinke[17],DowslandandDows-land[16]andDyckhoﬀetal.[18].ResultsontheprobabilisticanalysisofpackingalgorithmscanbefoundinCoﬀmanandShor[12]andCoﬀmanandLueker[11].Letusintroducetheproblemsinamoreformalway.Wearegivenasetofnrectangularitemsj2J¼f1;...;ng,eachdeﬁnedbyawidth,wj,and

aheight,hj:

(i)intheTwo-DimensionalBinPackingProblem(2BP),wearefurthergivenanunlimitednum-berofidenticalrectangularbinsofwidthWandheightH,andtheobjectiveistoallo-catealltheitemstotheminimumnumberofbins;(ii)intheTwo-DimensionalStripPackingProblem(2SP),wearefurthergivenabinofwidthWandinﬁniteheight(hereaftercalledstrip),andtheobjectiveistoallocatealltheitemstothestripbyminimizingtheheighttowhichthestripisused.

Inbothcases,theitemshavetobepackedwiththeirw-edgesparalleltotheW-edgeofthebins(orstrip).Wewillassume,withnolossofgenerality,thatallinputdataarepositiveintegers,andthatwj6Wandhj6H(j¼1;...;n).

BothproblemsarestronglyNP-hard,asiseasilyseenbytransformationfromthestronglyNP-hard(one-dimensional)BinPackingProblem(1BP),inwhichnitems,eachhavinganassoci-atedsizehj,havetobepartitionedintothemini-

mumnumberofsubsetssothatthesumofthesizesineachsubsetdoesnotexceedagivenca-pacityH.Athirdrelevantcaseofrectanglepackingisthefollowing.Eachitemjhasanassociatedproﬁtpj>0,andtheproblemistoselectasubsetof

items,tobepackedinasingleﬁnitebin,whichmaximizesthetotalselectedproﬁt.Thisproblemisusuallydenotedas(Two-Dimensional)Cutting

Stock,althoughithadbeenintroducedbyGilmoreandGomory[29]as(Two-Dimensional)CuttingKnapsack.Inthissurveyweconcentrateontwo-dimen-sionalproblemsinwhichallitemshavetobepacked,i.e.,on2SPand2BP.Thereaderisre-ferredtoDyckhoﬀetal.[18,Section5]foranannotatedbibliographyontwo-dimensionalcut-tingstockproblems.Forboth2SPand2BP,wealsoconsiderthespecialcasewheretheitemshavetobepackedintorowsforminglevels.InSection2wediscussmathematicalmodelsforthevariousproblemsintroducedabove.InSection3wesurveyclassicalapproximationalgo-rithmsaswellasmorerecentheuristicandmeta-heuristicmethods.InSection4weintroducelowerboundingtechniques,whileinSection5wede-scribeexactenumerativeapproaches.