South Pole温度风速廓线的统计分析

利用2008年South Pole的探空资料,通过大气温度和风速廓线,确定了South Pole地区冬季（6,7,8月）和夏季（12,1,2月）的大气边界层结构,边界层和对流层顶的高度。对近地面的温度、水汽压、风速和风向进行了统计分析。结果表明,South Pole大气边界层大多时候为稳定型,但在夏季也存在不稳定的情况,尤其在1月份较多;夏季夜晚的边界层平均高度为389米,比白天的304米大,冬季夜晚的边界层平均高度为591米,大于夏季夜晚;夏季白天对流层顶平均高度比夜晚略大,分别为6172米和5770米。South Pole高层大气理查森数的倒数基本都小于4,发生湍流的可能性很小。     

高校固定资产管理中云计算技术的应用探讨

随着时代的发展,国家对人才的需求量不断增加,并且对人才培养的要求越来越高。高校作为人才输出的重要基地,人们对高等教育的重视程度不断加深,尤其是近年来高校在发展的过程中其规模也在不断的扩展,导致固定资产管理中的一些问题逐渐凸显出来。本文就固定资产管理中存在的问题进行分析,进一步探讨云计算技术在高校固定资产管理中的应用。     

低云中短波红外表观辐射模型研究

在对空红外系统的多光谱探测和红外仿真中，云的干扰不可忽略，所以，对云的辐射特性的研究至关重要。在不同的波段，云的辐射特性会有很大的差异，为了研究各个不同波段云的表现辐射特性．需要计算云的光谱辐射量。在典型观测模式下建立了低云的表观光谱辐射模型，研究了对云背景辐射有贡献的各个辐射分量的计算方法。基于传统的二流近似模型获取各个参数，引入云的光谱光学厚度的经验公式。进而获得了低云在中短波段的光谱辐射特性，有效地计算出了云背景在1-5μm的中短波段内的表现光谱辐亮度数据，并且节省了计算时间。经过比较发现，该模型的计算结果与实测结果有较好的一致性。可以为云背景多光谱分析、探测及仿真提供背景数据。     

狭叶柴胡根发育过程中柴胡皂苷积累的超微细胞化学研究

用醋酸铅溶液对狭叶柴胡（Bupleurum scorzonerifolium Willd.）根内的药用成分柴胡皂苷进行细胞化学定位,在透射电镜下探讨不同发育时期根的结构特征与柴胡皂苷积累的关系。结果表明：狭叶柴胡根的初生结构和次生结构类似一般双子叶植物。在根的初生分生组织中表皮原及皮层原均有皂苷的分布。在根的初生结构中,柴胡皂苷分布于表皮、皮层、中柱鞘、初生韧皮部及原生木质部的薄壁组织细胞内,其中中柱鞘和韧皮部是主要的分布部位。在根的次生结构中,柴胡皂苷主要分布于中柱鞘和次生韧皮部薄壁组织细胞内,在次生木质部及形成层中也有少量分布。高尔基体可能与皂苷的合成有关,且胞间连丝参与皂苷的运输。柴胡皂苷在幼嫩结构中的含量高于次生结构,但其总含量低于次生结构。     

我国周边国家和地区的CO2本底浓度及对比分析

利用世界温室气体数据中心（WDCGG）数据资料和WMO资料,对中国大陆及周边国家和地区的主要温室气体CO2浓度等进行了初步分析。分析结果表明：总体而言,中国大陆瓦里关全球大气本底站与中国香港、日本、俄罗斯、韩国等周边国家和地区CO2浓度水平相近,变化趋势一致;中国香港和韩国CO2的浓度较高,日本、俄罗斯和中国瓦里关的浓度较低。多年观测数据的研究分析显示,北半球CO2平均浓度呈现逐年升高态势,且CO2平均年变化幅度与观测站所处海拔高度成反比。中国瓦里关全球本底站与美国Mauna Loa、Barrow、Trinidad Head全球大气本底站CO2浓度水平和变化趋势较为一致,年际变化幅度略高于Mauna Loa站,低于Barrow站。中国上甸子区域大气本底站CO2浓度变化比瓦里关及美国Mauna Loa、Barrow、Trinidad Head站剧烈,显示出上甸子站受区域排放影响较强的特性。     

电子式互感器性能检测及问题分析

电子化、数字化时代的不断向前发展,互感器也不断进行电子化升级.电子式的互感器主要是用于量测和保护系统,进行对电力系统中电参量的测量,同时对不同种类的电气设备进行检测以及其设备功效的检测评价.就目前而言,电子式的互感器在数字化的变电站中扮演着一个极其重要的角色,作为一个重要的设备,其在电气系统的正常运行中起着重要的保障作用.然而,电子式的互感器在中国的试点运行中依然存在或大或小的问题,因此,为了促进电子式的互感器的技术研究,推动其在我国的运用的可靠性和稳定性,本文对电子式的互感器的性能检测进行了简短分析,并在此基础上对该过程中出现的问题进行了探索研究,以期在今后的相关实践工作能够更顺利地进行.     

基于2007-2013年COSMIC掩星数据的电离层振幅闪烁研究

利用2007-2013年的COSMIC掩星数据，分析了E区与F区电离层闪烁的变化特征.发现用闪烁出现频次、闪烁发生率以及闪烁强度来表征的电离层闪烁出现规律比较相似.E区电离层闪烁在夏季半球的中纬地区最强，其次是春秋季的低纬地区和冬季半球.就经度分布来说，春秋季E区电离层闪烁呈四波结构.对F区电离层闪烁来说:南美-大西洋扇区在12月至点最为显著；非洲和太平洋扇区在6月至点最为显著；大西洋扇区在春秋分季最为显著.极区也出现中等强度的闪烁，尤其在南半球的90°E~180°E扇区较为显著.高纬E区电离层闪烁强度随太阳活动的增强而增强，而低纬和南半球的中纬E区闪烁随太阳活动的增强而减弱.高纬和低纬F区闪烁随太阳活动的增强而增强，而中纬F区电离层闪烁对太阳活动无显著依赖关系.对于赤道区来说，北半球60°W~60°E经度区闪烁强度随太阳活动的变化最为显著，其次是南半球60°E~210°E附近；而对于高纬地区来说，F区闪烁强度随太阳活动的变化最为显著的区域在南半球60°E~210°E附近.     

Recent propagation studies in Japan

Reviews activities in the field of propagation research, in the 1990s, in Japan. The authors focus only on propagation studies related to radio communications; activities in the field of remote sensing are outside the scope of this review. Since Kagoshima and Shiokawa (1992) included a short review of research activities in this field, in the period from 1989 to 1991, the emphasis of the present review is placed on activities after this period. The list of references consists of only papers written in English, which have appeared in international journals or published proceedings of international conferences. Reflecting the activities of various fields of propagation research in Japan, two-thirds of the review is devoted to propagation studies related to mobile communications, including land-mobile, mobile-satellite, and indoor communications. The rest of the review covers other basic studies, related to propagation through the atmosphere and precipitation     

Surgical applications of lasers

Because of an ability to coagulate, ablate, or vaporize tissue, argon, CO2, and Nd:YAG lasers have been employed extensively in surgery. The capability of transmitting argon and neodymium YAG energy through a flexible fiber which may be inserted in a fiberoptic instrument allows the application of the laser in a number of anatomic areas without the need for an incision. Extensive application has been made in utilizing laser techniques in treating lesions of the gastrointestinal tract, skin, central nervous system, bladder and urethra, spine, joints, ear, nose and throat, and in general surgery to provide control of bleeding. Surgical advances in the application of lasers would be assisted by engineering developments such as a tuneable laser, a flexible carbon dioxide transmission fiber, miniaturization, reduction in cost, improvement in cooling systems, and portability of the laser surgical instrument.     

On the ballistic transport in nanometer-scaled DG MOSFETs

The scattering effects are studied in nanometer-scaled double-gate MOSFET using Monte Carlo simulation. The nonequilibrium transport in the channel is analyzed with the help of the spectroscopy of the number of scatterings experienced by electrons. We show that the number of ballistic electrons at the drain-end, even in terms of flux, is not the only relevant characteristic of ballistic transport. Then, the drive current in the 15-nm-long channel transistor generations should be very close to the value obtained in the ballistic limit even if all electrons are not ballistic. Additionally, most back-scattering events, which deteriorate the on current, take place in the first half of the channel and, in particular, in the first low field region. However, the contribution of the second half of the channel cannot be considered as negligible in any studied case i.e., for a channel length below 25 nm. Furthermore, the contribution of the second half of the channel tends to be more important as the channel length is reduced. So, in ultrashort-channel transistors, it becomes very difficult to extract a region of the channel, which itself determine the drive current I/sub on/.     

扬声器单元TS参数偏差对系统频率响应曲线的影响

在闭箱、开口箱、被动辐射体箱和带通箱系统的设计中,人们已认识到单元的TS参数和箱体的声学参数有紧密的配合关系。一旦箱体的结构设计有所确定,安装在箱体上的扬声器单元的TS参数也必须确定,这样,系统的低音频特性就因此而定。但是在批量投产时,TS参数的偏差将对系统的低音频特性产生变化。以开口箱的系统频率响应曲线为分析目标,要观察TS参数的偏差所产生的变化。为此,采用LEAP5扬声器设计软件作相应的模拟,证明只要TS参数的偏差在一定的范围内,频率响应曲线的变化也可以维持在一个偏差带内。这样,可根据系统的技术指标来确定TS参数的偏差。     

Noise in solid-state devices and lasers

A survey is given of the most important noise problems in solid-state devices. Section II discusses shot noise in metal-semiconductor diodes, p-n junctions, and transistors at low injection; noise due to recombination and generation in the junction space-charge region; high-level injection effects; noise in photodiodes, avalanche diodes, and diode particle detectors, and shot noise in the leakage currents in field-effect transistors (FETs). Section III discusses thermal noise and induced gate noise in FETs; generation-recombination noise in FETs and transistors at low temperatures; noise due to recombination centers in the space-charge region(s) of FETs, and noise in space-charge-limited solid-state diodes. Section IV attempts to give a unified account of 1/f noise in solid-state devices in terms of the fluctuating occupancy of traps in the surface oxide; discusses the kinetics of these traps; applies this to flicker noise in junction diodes, transistors, and FETs, and briefly discusses flicker noise in Gunn diodes and burst noise in junction diodes and transistors. Section V discusses shot noise in the light emission of luminescent diodes and lasers, and noise in optical heterodyning. Section VI discusses circuit applications. It deals with the noise figure of negative conductance amplifiers (tunnel diodes and parametric amplifiers), and of FET, transistor, and mixer circuits. In the latter discussion capacitive up-converters, and diode, FET, and transistor mixers are dealt with.     

Influence of water absorption by silicate glass on the strains in passivated Al conductor lines

X-ray diffraction strain measurements and elastic recoil detection analysis of aluminum conductor lines, passivated with silicon oxide, showed that the absorption of water molecules in the passivation layer directly influences the strain state in the lines. Volume changes of the passivation due to water absorption lead to unusual strain states, where the line is strained in compression in the width direction and in tension in the height and length direction, with the largest component in the height direction. The process of water absorption, as well as the rearrangement of the strain components in the lines, was found to be reversible.     

Simulation of lung function evolution after heart-lung transplantation using a numerical model

A morphometry-based computational model for expiratory flow in humans was used to study the unusual configuration of the maximum expiratory flow-volume (MEFV) curve associated with alterations in lung function after heart-lung transplantation (HLT). The postoperative MEFV curve showed a peak, followed by a gently sloping plateau over the midvolume range, ending in a knee where the flow suddenly fell, instead of the usual observed uniform decrease in expiratory flow. We have tested several hypotheses about the relationship between the pattern of changes in the configuration of the MEFV curve and pathological changes in the airway mechanics through computer simulations. Principally, effects of lung denervation and airway obstruction, associated with the development of bronchiolitis obliterans in the lung periphery, have been investigated. The calculated curves are similar in appearance to the measured postoperative flow-volume curves and confirm reliability of the earlier hypotheses. We conclude that the plateau-knee configuration of the MEFV curve can result from flow limitation in one of the first airway generations, that this flow limitation coupled with an increase in peripheral airway resistance results in plateau shortening, and that flows exceeding predicted values during the second part of expiration may be produced by lung denervation. Additionally our results demonstrate that airways larger than the transitional and respiratory bronchioles can be involved in pulmonary function deterioration observed in patients affected with obliterative bronchiolitis. Our findings indicate that the computational model, based on a symmetrical dichotomous branching structure of the bronchial tree, along with pathological data, can be employed to evaluate the effects of heterogeneous changes in the lung periphery. Index Terms-Airway mechanics, forced expiration, lung transplantation, mathematical modeling, maximal expiratory flow-volume curve.     

Regulatory reform in the broadcasting industries of Brazil and Argentina in the 1990s

Regulatory reform has changed the organization of the broadcasting industry in Brazil and Argentina in the past decade. Although responding to a similar set of pressure, the pace, instruments, and character of reforms have been different in the 2 countries, resulting in media markets of diverse natures. This study argues that these different policy outcomes in the reform of broadcasting regulation in Brazil and Argentina reflect variations in three factors: the nature of the political system, the structure of the existing broadcasting industry, and the ideological legacy in the regulation of communication industries. The case of regulatory reform in the broadcasting industry illustrates different policy patterns in the restructuring of state-industry relations in communications and information technology industries in the 2 neighboring countries.     

真空光镊系统及其在精密测量中的研究进展

光镊具有非接触、低损伤和适用范围广等特性,被广泛应用于生命科学、纳米科技等领域。光镊系统通过调制束缚光场操控机械振子的运动,借助光动量和角动量的检测获取振子的运动状态,以实现对振子物理参量的精密测量。与传统液体光镊系统不同,真空光镊系统中的机械振子可获得与外界环境近乎完全隔离的状态,具有超高灵敏度的探测能力,是精密测量和基础物理研究的理想平台。首先介绍了真空光镊系统相关的基础理论,然后介绍了真空光镊系统的实验配置方案及其在精密测量中的典型应用,最后总结了真空光镊系统的发展现状,并给出了未来的发展建议。     

Analog behavioral modeling by multi-companding and wavelet collocation method

In this paper, we develop a wavelet collocation method with multi-companding for behavioral modeling of analog circuits. In the multi-companding procedure, the nonlinear companding algorithm is developed to control the error distribution continuously, while the adaptive scheme is employed to reduce the number of used wavelets. Consequently, the proposed multi-companding algorithm can not only modify the modeling error distribution continuously but also decrease the number of basis functions efficiently. Moreover, the companding function generation is automatic and can be applied for the behavioral modeling of any analog circuits. Jun Tao received the B.S degree in electrical engineering from Fudan University, China, in 2002. Now she is currently working toward the Ph.D. degree in micro-electronic engineering at the Fudan University. Her research interest includes analog behavioral modeling, analog circuit simulation and DFM. Xuan Zeng (M97) received the B.Sc. and Ph.D. degrees in electrical engineering from Fudan University, Shanghai, China, in 1991 and 1997, respectively. She joined the Electrical Engineering Department, Fudan University in 1997 and became a full professor in Microelectronics Department in 2001. Now she serves as the Vice Director of ASIC & System State key Lab. and the Associate Head of Microelectronics Department Fudan University. She was a visiting professor in the Electrical Engineering Department, Texas A&M University, USA and Microelectronics Department of TU Delft, Netherland in 2002 and 2003 respectively. Her research interests include DFM, analog and mixed signal design automation (behavioral modeling, circuit simulation and analog layout generation), high speed interconnect analysis and design and ASIC design. Dr. Zeng received the Cross-Century Outstanding Scholar Award from the Ministry of Education of China in 2002. She was selected into “IT Top 10” in Shanghai China in 2003. She served in the technical program committee of IEEE/ACM ASP-DAC in 2000 and 2005. Dian Zhou received the B.S degree in physics and M.S degree in electrical engineering from Fudan University, China, in 1982 and 1985, respectively, and the Ph.D. degree in electrical and computer engineering from the University of Illinois in 1990. He joined the University of North Carolina at Charlotte as an assistant professor in 1990, where he became an associate professor in 1995. He joined the University of Texas at Dallas as a full professor in 1999, and joined Fudan university as a Changjiang Professor in 2003 (on-leave from the University of Texas at Dallas). Currently, he serves as the dean of Microelectronics School, director of National Key Lab. on ASICs and Systems, and director of Miro-nano-electronics Innovation Platform at Fudan University. His research interests include: High-speed VLSI systems, CAD tools, mixed-signal ICs, and algorithms. Charles Chiang received his Bachelor degrees from the Department of Political Science, Tunghai University at Taichung, Taiwan in 1980, and Department of Computer Science, New Mexico State University, Las Cruces, New Mexico in 1986. Then he had his Masters and Ph.D. degree from the Department of Electrical Engineering and Computer Science, Northwestern University, Illinois in 1988 and 1991, respectively. After working at IBM and EDA companies for 10 years, he joined the Advanced Technology Group at Synopsys, Inc. in 2001. His research interests include routing, placement, floorplan, and signal integrity. His main research focus is now on design for manufacturability (DFM). Dr. Chiang has been a Senior Member of IEEE since 1998. He received the Superior Design Recognition award and the ADAL award from IBM Rochester in 1993 and 1994, respectively. He is one of the top 15 winners with new patent filing in 2005 and 2006 in Synopsys. He has served on the technical committee of ICCAD from 2004 to 2006, on that of Field Programming Logic (FPL) from 2002 to 2003, as well as on the committee of ASP-DAC in 2007. He has published more than 40 technical papers and filed 10 US patents.     

现实场景深度采集系统设计

近年来现实场景深度在各种场景下都得到了广泛的应用：在家庭中有家用智能清扫机器人、家庭服务机器人;在工厂中有应用于物流的自动导引运输车(WMR);在野外考察中有探测机器人;在战场上中有侦察、排雷机器人。这些应用的场景大多非常复杂,因此建立准确的场景模型对于未知环境中的工作非常重要。     

The measurement of oxygen saturation in arterial and venous blood

This article describes about the non-invasive optical measurement techniques to assess oxygen saturation in arterial and venous blood. The pulse oximeters for arterial oxygen saturation measurement use light in two wavelengths, in the red and infrared regions, and calibration is used to account for the difference in optical path-length between them. The accuracy of the commercial pulse oximeters is adequate for monitoring patients during surgical operation, where the clinical information that is needed is the absence of dramatic deterioration in the respiration efficiency. However, the error in pulse oximetry is too high for the clinical assessment of lung function, probably because of the need for calibration in the available technique. The use of two wavelengths in the infrared, instead of one wavelength in the red and one in the infrared region, enables the use of pulse oximetry without calibration. The technique can also be used for determining venous blood saturation, which is important for assessment of the adequacy of tissue blood supply.     

正确把握电信发展规律

二十世纪末，全球网络经济过热和电信业陷入之际，正是中国电信业深化体制改革、破除垄断、全面引入竞争之时。面对复杂的国际国内形势，中国电信业在一系列关系发展全局的重大问题上，坚持理性与务实，保持了行业积极稳健的发展。我国电信业目前正处于新的发展时期，面对新的机遇和挑战，在总结国内外实践的基础上，要进一步加深对电信发展基本问题的认识，要正确处理好一系列带有全球性、战略性、方向性的重大关系问题。