基于统一方程多种配置的GF-INS技术研究

采用加速度计取代陀螺仪作为惯性测量元件构建的无陀螺惯导系统（GF-INS），具有成本低、体积小、机动性能好等优点，已成为近年来惯性技术应用领域的研究热点。文中从理论上分析研究了GF-INS加速度计的输出方程，提出了基于统一方程的GF-INS解算的一般过程，并进行了理论推导。研究表明，不同加速度计配置方案只是选取了不同的参数，解算本质是一致的。结合国内外相关研究成果，对GF-INS的研究与发展提出了若干建议。     

基于PWM的平均转矩矢量合成方法在毫米级微型机器人精密定位中的应用研究

提出了基于PWM的平均转矩矢量合成的方法,克服了因为加工工艺限制而无法提高微型电动机步进精度的困难,将步进精度从原来的0．22mm提高到0．072mm,同时电机转动过程中输出力矩保持恒定,从而实现了全方位微型移动机器人的高精度定位。     

Static strength of a composite butt joint configuration with different attachments

The static failure behaviour of a composite single-strap joint configuration using three different attachments was studied experimentally. The attachments used were: adhesive bonding; mechanical bolting; and bonded-bolted joining. The dimensions of the composite butt joint used were determined based on actual joint configurations in aircraft structures, such that the test results would be beneficial to both the academic exploration and practical engineering application for advanced composite joint design and analysis. A damage evolution process was presented for the bonded-bolted butt joints based on the observed stress versus displacement curves and associated failure modes from all the related butt joints with the three attachments. An approach was then proposed for estimating the ultimate tensile strength in the bonded-bolted joints.     

不同层隔震结构在近断层地震作用下动力响应分析

选用天然橡胶支座(LNR)与铅芯橡胶支座(LRB)作为两栋8层钢筋混凝土结构的隔震装置,对其分别输入172条近断层地震波,计算隔震层设置在基础或以上每一层时隔震结构的动力响应,分析近断层地震动对不同层隔震结构动力响应的影响。分析结果表明：隔震结构输入能量小于非隔震结构输入能量,LRB隔震结构的输入能量小于LNR隔震结构的输入能量;随着隔震层的上移,隔震支座位移减小,顶层最大加速度增大。近断层地震动特征参数与不同层隔震结构动力响应参数均存在相关性,但相关程度不同。隔震结构设计要根据建筑结构动力响应的需求,同时考虑隔震层位置与地震动特征参数的影响。     

Bioinspired aquatic microrobot capable of walking on water surface like a water strider

Walking on the water surface is a dream of humans, but it is exactly the way of life for some aquatic insects. In this study, a bionic aquatic microrobot capable of walking on the water surface like a water strider was reported. The novel water strider-like robot consisted of ten superhydrophobic supporting legs, two miniature dc motors, and two actuating legs. The microrobot could not only stand effortlessly but also walk and turn freely on the water surface, exhibiting an interesting motion characteristic. A numerical model describing the interface between the partially submerged leg and the air-water surface was established to fully understand the mechanism for the large supporting force of the leg. It was revealed that the radius and water contact angle of the legs significantly affect the supporting force. Because of its high speed, agility, low cost, and easy fabrication, this microrobot might have a potential application in water quality surveillance, water pollution monitoring, and so on.     

三星的TOP奇迹

过不了多久,在洛桑的国际奥委会总部的奥运博物馆里,在那面深灰色的墙上,就将出现"LENOVE"(联想)的名字.     

Judgments of approach speed for motorcycles across different lighting levels and the effect of an improved tri-headlight configuration

The misperception of vehicle approach speed is a key contributory factor to road traffic crash involvement. Past research has indicated that individuals use the rate of visual looming to calculate the time to passage (TTP) of a vehicle, and that smaller vehicles loom to a lesser extent than larger vehicles. Despite a disproportionate number of fatal injuries occurring on the road after dark, and a higher than average number of accidents involving automobile drivers violating the right of way of a motorcyclist occurring in low light conditions, there has been very little consideration of the accuracy of TTP for smaller and larger vehicles under low levels of luminance. We investigated drivers’ judgments of motorcycle and car approach speeds across a number of levels of luminance within a virtual city scene, as well as the effectiveness of a tri-headlight formation on motorcycle speed judgments. The accuracy of car approach speed judgments were not affected by changes in lighting conditions, but speed judgments for the solo headlight motorcycle became significantly less accurate as lighting reduced in the early night and night-time conditions. Incorporation of a tri-headlight formation onto the standard motorcycle frame resulted in improved accuracy of approach speed judgments, relative to the solo headlight motorcycle, as ambient light levels reduced. The practical implications of the findings are discussed in terms of road safety and motorcycle design.     

Planar configuration for image projection

A flat panel, compact virtual image projection display is presented. It is based on a light- guided optical configuration that includes three linear holographic gratings recorded on one planar transparent substrate so as to obtain a magnified virtual image for a small input display. The principles of the projection display, unique design, and procedures for experimentally recording an actual planar configuration are presented, along with evaluation results. The results reveal that a field of view of +/-8 degrees can be readily achieved at a distance of 36 cm, making such planar configurations attractive for head-up displays.     

倪云林的厕所

元末大画家倪瓒的厕所茅坑里覆盖了厚厚一层白色鹅毛。粪便落入坑中后,鹅毛飘起覆盖之,便不见污秽。不过文献没有记录厕所的其他措施,但这个历史上最著名的洁癖（他怕妓女不干净,让她反复洗浴直到天明都无法说服自己进行房事．最后不了了之）一定还有其他办法除臭的只是不得而知。     

Two by two: the story of the ARC

In the years immediately following the Second World War, there was much activity in both the USA and the UK to develop electronic computers. In this article, the author, then a Fellow at Birkbeck College London, recalls his own work to design a machine using relays-the automatic relay calculator (ARC). This was subsequently developed into a fully electronic computer APE(X)C, a version of which was sold by ICL. A key feature of these machines was the use of a magnetic drum store     

平缝机的组态设计方法研究

为了提高平缝机产品的设计效率和质量,提出了一种组态式产品设计方法,并给出了基于组态技术的产品开发流程,分析了组件化设计的方法.在应用层次分析法和模糊综合评判算法的基础上,对组件的确定过程进行了详细阐述,并通过生成性规则和修改性规则两种准则来完成组件的设计.最后,应用该组态设计方法对平缝机进行产品设计开发,验证了该方法的...     

Algorithms for the model configuration problem

The model configuration problem is a combinatorial optimization problem that arises in the context of switching cabinet manufacturing in the telecommunication industry. We discuss the manufacturing environment and define the q-model problem in this context, for q ≥ 1. We then discuss the structural properties of the q-model problem, and propose an efficient procedure for solving the 1-model problem. We also propose several heuristic procedures for solving the 2-model problem, and present an evaluation of these procedures through an extensive computational experiment.     

Upgraded coil configuration for ISABELLE magnets

Achievement of the design field of 5 T in the ISABELLE dipole magnets is turning out to be more arduous than expected and several avenues of improvement are being pursued. One possibility for improving training and peak field performance is discussed in this paper. It has been recognized that the inert spacers with their adjacent active turns in the cosine magnet windings can be replaced by a double thickness braid operating at approximately half-current density in 46 of the 190 turns. Since the high-field region occurs in the low current density turns near the poles, a performance improvement can be expected. It has been verified that the proposed coil configuration satisfies the field requirements and details thereof are given. Results from an experimental magnet in which superconducting spacer turns are used to simulate half-current density windings are presented. Construction of thick braid coils is being planned and the status of these magnets is reviewed.     

Rise of silicene: A competitive 2D material

Silicene, a silicon analogue of graphene, has attracted increasing attention during the past few years. As early as in 1994, the possibility of stage corrugation in the Si analogs of graphite had already been theoretically explored. But there were very few studies on silicene until 2009, when silicene with a low buckled structure was confirmed to be dynamically stable by ab initio calculations. In spite of the low buckled geometry, silicene shares most of the outstanding electronic properties of planar graphene (e.g., the “Dirac cone”, high Fermi velocity and carrier mobility). Compared with graphene, silicene has several prominent advantages: (1) a much stronger spin–orbit coupling, which may lead to a realization of quantum spin Hall effect in the experimentally accessible temperature, (2) a better tunability of the band gap, which is necessary for an effective field effect transistor (FET) operating at room temperature, (3) an easier valley polarization and more suitability for valleytronics study. From 2012, monolayer silicene sheets of different superstructures were successfully synthesized on various substrates, including Ag(1 1 1), Ir(1 1 1), ZrB₂(0 0 0 1), ZrC(1 1 1) and MoS₂ surfaces. Multilayer silicene sheets have also been grown on Ag(1 1 1) surface. The experimental successes have stimulated many efforts to explore the intrinsic properties as well as potential device applications of silicene, including quantum spin Hall effect, quantum anomalous Hall effect, quantum valley Hall effect, superconductivity, band engineering, magnetism, thermoelectric effect, gas sensor, tunneling FET, spin filter, and spin FET, etc. Recently, a silicene FET has been fabricated, which shows the expected ambipolar Dirac charge transport and paves the way towards silicene-based nanoelectronics. This comprehensive review covers all the important theoretical and experimental advances on silicene to date, from the basic theory of intrinsic properties, experimental synthesis and characterization, modulation of physical properties by modifications, and finally to device explorations.     

Common-path optical heterodyne profilometer: a configuration

A novel configuration that combines a linearly polarized He-Ne laser and a birefringent lens to produce a common-path polarized optical heterodyne profilometer with respect to the heterodyned P and S waves has been set up. In this profilometer a linear polarized frequency-stabilized He-Ne laser was used with an acousto-optical modulator to replace the Zeeman laser as the light source that had two polarization eigenstates in different temporal frequencies. The proposed interferometer shows a more symmetric and ideal common-path structure than the conventional optical heterodyne profilometers with the Zeeman laser. The phase error aroused by the elliptical polarization and the nonorthogonality of the two eigenpolarization modes of the Zeeman laser can be reduced. The system's resolution in the vertical direction reaches 2 A, and in a 27-mum scanning range the repeatability of the surface profile measurements is shown to be 5 A.     

大批量定制环境中的产品配置规则

本文主要对产品配置中的配置机理及其实现进行研究;首先,论述了大批量定制模式中的产品配置技术,分析了目前基于规则驱动的产品配置技术的发展和优缺点;其次,讨论了面向产品族群的产品配置中的规则构件方法,并提出了基于此理论的产品配置框架;然后,重点阐述了面向产品族群的、通用的产品配置中规则的结构,并给出了规则配置的算法和规则匹配引擎的推理流程;最后,通过案例分析验证了此技术的可行性,并给出了基于此技术实现的产品配置系统的运行实例.