冷轧薄宽带钢局部型中浪瓢曲变形行为研究

针对薄宽带钢冷轧过程中易发多发的局部型中浪瓢曲缺陷,引入非均匀载荷宽度、弹性约束系数及平均张应力建立了屈曲变形的解析计算模型。应用能量最低原理对屈曲变形区域进行搜索求解,得到了局部型中浪屈曲临界条件(包括临界应力、屈曲波长和屈曲波宽),获得了其与非均匀载荷宽度、弹性约束系数、平均张应力的关系,并发现平均张应力是产生局部型中浪的重要影响因素。应用样条有限元方法对局部型中浪进行数值仿真分析,验证了屈曲解析计算方法的正确性。在实验轧机上进行了轧制研究,通过轧制获得了局部型中浪屈曲模态,对实验结果分析得到了相对应的屈曲临界条件,与解析法和样条有限元法结果基本吻合,证明了样条有限元计算方法与解析计算方法的正确性及其工程应用价值。     

9.3大阅兵:高标准让军魂荡气回肠

<正>阅兵是展示辉煌的时刻,而为这一辉煌采取的所有的标准,不啻也是宝贵的财富,应当成为践行标准的榜样……这个月最令人难忘、最引人自豪、最提振国威的事情,当属"9.3"大阅兵,它有着以往没有的多重的亮点:首次以纪念抗日战争暨世界反法西斯战争胜利为阅兵主题,彰显维护和平是全世界人民共同的愿望。首次邀请外国军队代表参加分列式,体现纪念大会的国际性。首次组织抗战老兵包括国民党老兵参加,体现了对历史的尊重,体现全民族抗战的特色。首次编组英模部队方队受阅,展示中国共产党在抗战中定海     

云冈遗韵

<正>云冈石窟,历经1540年的人间风雨而硕立至今的那种坚强、博爱与宽容的佛国神界!这净25米高的崖壁上蜂窝般开凿出的是人间的奇迹,人类的智慧,     

分光光度计使用维护的注意事项

一、分光光度计检定的主要项目对分析结果的影响 1.波长准确度 分光光度法必须对应于样品吸收光谱中的某一个吸收峰的波长.但由于仪器本身存在的误差和不同的人员进行测量时产生的误差,单色光的实际波长与仪器的波长读数值之间会存在一定的误差.     

乡野如画醉金秋

秋天在不经意间早已悄然远去,留下的是那金色的记忆。乡野的秋色金灿灿。柿子树上硕果累累,红红火火的柿子和层次分明、错落有致的黑色枝干在弥漫的烟雾中若隐若现、飘逸洒脱,宛如一幅写意的国画。     

国内外仪器指标的接轨与合格判断

随着科学技术的发展和科研任务的需要,测量仪表的使用大幅度增加,因此检定的任务量也随之大幅攀升.其中国外仪表占了很大的比重,但在仪器技术指标的表达方式上国外各个厂家不尽相同,与国内计量术语和仪器技术指标的表达方式更是存在较大的差异,这对于仪器的使用和计量检定的合格性判断是一个重要的问题,关系到购置仪器的验收与使用,进而关系到科研任务的质量保障.     

甲醛气体传感器研究进展

甲醛是室内空气的主要污染物之一,随着人们对室内空气污染的日益关注,对甲醛的准确及时检测显得更加重要.目前检测甲醛气体最为快速的方法就是传感器法.在综合分析了国内外甲醛气体传感器的研究现状的基础上,着重就测定甲醛的电化学传感器、基于化学发光的传感器、金属氧化物传感器、电子鼻、声表面波传感器的特性进行了阐述与剖析,指出了甲醛气体传感器存在的问题,并预测了其发展趋势.     

世界著名自驾车露营地

<正>露营在国外已经拥有超过100年的历史,露营地的管理和经营方式大多参照了酒店,也有星级之分。随着人们需求的变化,露营地提供的设施和服务也在不断跟进。如今,在一些著名的露营地,已经不仅仅能够看到为自驾车、房车露营者提供的营位和日常生活的基础设施,还有诸如高尔夫、骑行、划船等形式多样的体育运动,以及像毗邻历史悠久的古村落这样的特色看点。在很多国家,建立一个享有声誉的汽车营地甚至成为了拉动旅游业发展的重要手段之一,也因此得到了政府的大力支持。     

汽车阳极电泳线改造为阴极电泳线的实践

为了将车身涂装线中的阳极电泳改造成阴极电泳,在保留前处理不变的前提下,首先布置合理的工艺流程、确定阴极电泳工作原理,然后对阴极电泳的电泳槽、漆液主循环系统、超滤系统、阳极液循环系统、热交换循环系统、阴极电泳电源和电泳后清洗系统的技术参数进行认真的分析和计算,使改造后的阴极电泳的各项技术指标达到了设计的要求.结果表明,通过局部的技术改造,将车身涂装线的阳极电泳改造成阴极电泳完全可行.     

家的幸福瞬间

家是心灵的港湾,让我们寄托一生;家是人生的加油站,让我们纾解疲劳。家是能铺开心事的地方,家是受伤时的创口贴,家是握在手里盈盈一脉的馨香,家是每一砖每一石都用爱砌出来的城堡。家是以爱为圆心,一家人手牵手为半径走过的一个圆;家是整个世界在下雪,走进其中却是春天的角落;     

Patent information of the former USSR countries

The patent information currently available for the former USSR, EAPO, Russian Federation, Turkmenistan, Belarus, Tajikistan, Kazakhstan, Azerbaijan, Moldova, Armenia, Ukraine, Georgia, Kyrgyzstan, the Baltic countries and Uzbekistan is described. It is a complicated scene, in terms of the extent and depth of coverage, the media employed (paper, CD, on-line), and the use of open access, charged INTERNET access and commercial databases.     

Survey of Experimental Data of Thermophysical Properties for Difluoromethane (HFC-32)

A survey of experimental data for HFC-32 was prepared at the Institute of Thermomechanics in connection with planned experiments. In tabular form, surveys of thermodynamic, transport, and other property measurements, including pvT behavior, second virial coefficient, vapor pressure, saturation densities, critical parameters, heat capacities, speed of sound, thermal conductivity, viscosity, surface tension, refractive index, dielectric constant, and dipole moment, are presented. Tables include author)s) name(s), reference, year of publication, ranges of measurements, number of points, stated uncertainty, sample purity, and experimental method.     

高强度高模量玻璃纤维特性与应用

与传统E玻璃纤维相比,高强度高模量玻璃纤维在拉伸强度、弹性模量、抗冲击性能、耐高温性能、耐腐蚀性能、电绝缘性和介电性能等方面都具有明显优势,可广泛地应用于航空航天、国防军事、风力发电、交通运输、体育休闲、压力容器、建筑工程、管道、环境处理、石油、机械等许多领域,成为本行业研究与开发的热点和重点.     

Age and pedestrian injury severity in motor-vehicle crashes: a heteroskedastic logit analysis

This research explores the injury severity of pedestrians in motor-vehicle crashes. It is hypothesized that the variance of unobserved pedestrian characteristics increases with age. In response, a heteroskedastic generalized extreme value model is used. The analysis links explanatory factors with four injury outcomes: fatal, incapacitating, non-incapacitating, and possible or no injury. Police-reported crash data between 1997 and 2000 from North Carolina, USA, are used. The results show that pedestrian age induces heteroskedasticity which affects the probability of fatal injury. The effect grows more pronounced with increasing age past 65. The heteroskedastic model provides a better fit than the multinomial logit model. Notable factors increasing the probability of fatal pedestrian injury: increasing pedestrian age, male driver, intoxicated driver (2.7 times greater probability of fatality), traffic sign, commercial area, darkness with or without streetlights (2-4 times greater probability of fatality), sport-utility vehicle, truck, freeway, two-way divided roadway, speeding-involved, off roadway, motorist turning or backing, both driver and pedestrian at fault, and pedestrian only at fault. Conversely, the probability of a fatal injury decreased: with increasing driver age, during the PM traffic peak, with traffic signal control, in inclement weather, on a curved roadway, at a crosswalk, and when walking along roadway.     

Thermophysical properties of some key solids: An update

In 1985, the CODATA Bulletin published a Report of its Task Group on Thermophysical Properties of Solids which analyzed available data on, and gave recommended values for, the heat capacity of Cu, Fe, W, and Al₂O₃, the thermal expansion of Cu, Si, W, and Al₂O₃, the electrical resistivity of Cu, Fe, Pt, and W, the thermal conductivity of Al, Cu, Fe, and W, and the absolute thermopower of Pb, Cu, Pt, and W. The analysts for the different properties were R. B. Castanet, S. J. Collocott, P. D. Desai, C. Y. Ho, J. G. Hust, R. B. Roberts, C. A. Swenson, and G. K. White. The present paper is an updated version of the earlier report and includes more recent data which change some of the recommended values. notably the heat capacity of Cu and W and the thermal expansion of Si and W.     

The 21st century strategic plan: USPTO’s adjustment to the future

The USPTO’s 21st century strategic plan represents a fundamental reappraisal of the tasks, responsibilities, working practices and priorities of the office. It has gone through several versions in seeking the most effective and acceptable way forward. In this article the author reviews the key factors, opinions and changes at each stage of the plan’s development, primarily from the patent perspective. In doing so, he refers to patent pendency and related timeliness issues, such as staffing, productivity, and potential outsourcing of search, classification, reclassification and examination functions. Quality initiatives, such as search tool enhancements, review by second examiner and e-government, are also described, as are wider issues affecting the plan, such as fee diversion, government outsourcing, and globalization issues such as trilateral efforts to share workloads. In concluding, the author points out that, although not fully finalised, the strategic plan is now largely agreed in a form that meets the key requirements for quicker processing, better quality and a rapid move towards e-government, within realistic fee increases, without concomitant massive staff increases, and in stages, with each stage being preceded by firm proof of concept procedures.     

Hybrid features-enabled dragon deep belief neural network for activity recognition

Activity recognition is a challenging task in computer vision that finds widespread applications in various fields, such as motion capture, video retrieval, security, and video surveillance. The objective of this work is to present a technique for recognizing human activities in videos using Dragon Deep Belief Network (DDBN) and hybrid features, which comprises of features like shape, coverage factor, and Space-Time Interest (STI) points. Initially, the keyframes from the input video sequence are extracted using Structural Similarity (SSIM) measure. Then, the features, such as shape, coverage factor, and STI points, are extracted from the keyframes. Based on the feature vector extracted, the proposed DDBN classifier, which is designed by the effective combination of DBN and Dragonfly Algorithm (DA), a classification on human activities, such as walk, bend, etc. in videos. In DDBN, the weights in the network are selected optimally using DA. The weight update using the DA for each incoming feature improves the performance of the DDBN classifier. Further it improves the accuracy in classification of actions. The proposed DDBN classifier is experimented using KTH and Weizmann datasets based on three evaluation parameters, such as accuracy, sensitivity, and specificity. From the performance evaluation, the proposed DDBN classifier could attain better performance with the probability of 98.5% accuracy, 0.96 sensitivity, and 0.959 specificity, respectively.     

An Approach to Calculate Thermodynamic Properties of Mixtures Including Propane, <Emphasis Type="Italic">n</Emphasis>-Butane,and Isobutane

This paper discusses a mathematical model for computing the thermodynamic properties of propane, n-butane, isobutane, and their mixtures, in the fluid phase using a method based upon statistical chain theory. The constants necessary for computations such as the characteristic temperatures of rotation, electronic state, etc. and the moments of inertia are obtained analytically applying a knowledge of the atomic structure of the molecule. The paper presents a procedure for calculating thermodynamic properties such as pressure, speed of sound, the Joule-Thomson coefficient, compressibility, enthalpy, and thermal expansion coefficient. This paper will discuss, for the first time, the application of statistical chain theory for accurate properties of binary and ternary mixtures including propane, n-butane, and isobutane, in their entire fluid phases. To calculate the thermodynamic properties of Lennard-Jones chains, the Liu-Li-Lu model has been used. The thermodynamic properties of the hydrocarbon mixtures are obtained using the one-fluid theory. Paper presented at the Fifteenth Symposium on Theremophysical Properties, June 22–27, 2003, Boulder, Colorado, U.S.A.     

多波束测深系统多子阵检测法的改进及其性能分析

多波束测深系统中,相位检测法是实现超宽覆盖测量的关键技术之一。分析了分裂子阵相位检测法和多子阵检测法,并基于对子阵结构的分析,改进了多子阵检测法,给出了多子阵检测法输出信噪比的表达式,讨论了子阵结构对输出信噪比的影响,在理论分析基础上选择了三种子阵结构对海上试验数据进行了处理,验证了分析结果。处理结果表明,在优化参数基础上,多子阵检测法不但可实现多波束测深系统的超宽覆盖,而且可改善系统对海底的检测性能。     

p,V, T and derived thermodynamic data for toluene,trichloromethane, dichloromethane,acetonitrile, aniline,and n-dodecane

Experimentally determined p,V,T data are reported for toluene, trichloromethane, dichloromethane, acetonitrile, aniline, and n-dodecane at 278, 288, 298, 313, and 323 K, except for dichloromethane, for which the highest temperature was 298 K. At each temperature, measurements were done at pressures up to about 280 MPa or (for aniline and n-dodecane) at a lower pressure slightly below the freezing pressure at the temperature of measurement. Values of the isobaric expansivity isothermal compressibility and (for toluene, trichloromethane, dichloromethane, and acetonitrile) internal pressure, derived from the p,V,T data, are presented.