Vibration Analysis of Digital Radiography System for Large Container Inspection

The cantilever vibration characteristics of a digital radiography system were analyzed to predict the effect of vibration on the performance of a mobile container inspection system. The static deformation,vibration mode and natural frequency of the cantilever of the digital radiography system were calculated with the ALGOR Finite Element System to verify the strength and rigidity of the cantilever. The maximum amplitude of the cantilever vibration occurs as it starts accelerating. The predictions show good agreement with test results, indicating that the finite element model of the cantilever structure accurately models the mechanical characteristics.     

系统数字频响分析中若干条件的辨析及应用

讨论系统数字频响分析中的线性、时不变、因果、稳定、奇偶虚实分解及其对应等推导求解的条件,明确了如何正确应用这些条件.     

Investigation on the Cause of Excessive Vibration of an Offshore Platform

0　IntroductionWiththeexploitureanddrillingforoceanre source,offshore platformsaremost prolificandprevalentintheoffshoreindustrytoday .Asthefun damentalinstallationsofdevelopmentofoceanre sources ,designingrequirementsofoffshoreplatformsarebecomingmoreandmoreimportant.Underenvironmentalloadsduetowind ,cur rent ,waveandevenseismicprotectionattack ,off shoreplatformsinevitablyvibrateduringtheirlife time .While ,foranormalconditionthisvibrationissmallandtheoccupantsontheplatformdon tsenseitatall.…     

Contributions of different land cover types in Otindag Sandy Land and Bashang area of Hebei Province to the material source of sand stormy weather in Beijing

Different land cover types in Otindag Sandy Land and Bashang area of Hebei Province are linked to a material source of sand stormy weather in Beijing based on results of field vegetation and soil survey and laboratory works. Results of grain size analysis show that dust release potential in per unit area of moving sandy land is small,while lowland meadow and meadow steppe in stony hills have high potential of releasing dusts in per unit area during sand stormy weather occurrence. Further considering the effects of vegetation, it is inferred that the moving sandy land served as a material source of past dust storm and the possibility of dust release in per unit area is low in current time.Typical steppe in stony hills is undergoing desertification and its dust release possibility in per unit area is high. Farmland has strong potential of release dusts when they are ploughed in spring, but a large amount of therophytes grow and thus prevent dusts from release when cultivation was terminated.Potentials of dust release in per unit area in fixed sand dunes,stony mountain meadow steppe and low land meadow are lowdue to high cover of perennials. Sand dune reactivation and desiccation of lakes and lowlands under estimated future climatic change will make them serve as a future material source of sand stormy weather.     

Identification and mapping of quantitative trait loci controlling cold-tolerance of Chinese common wild rice (O. rufipogon Griff.) at booting to flowering stages

Cold injury is an important limitation of rice production. Therefore, screening for cold-tolerant genetic resources and the development of highly cold-tolerant cultivars is crucial for higher yield potential and stable yield of rice. There have been several reports on the genetic analysis and QTL mapping of the cold-tolerance at the booting stage. Toriyama et al.[1,2] and Futsuhara et al.[3,4] reported that 4 or more genes were involved in the cold-tolerance. Several QTLs at the booting sta…     

模糊分析在油气储量产能预测中的应用--以靖安油田盘古梁区开发数据为例的分析

针对常规因素分析法在实际应用中所存在的一些问题 ,在阐述模糊分析理论特点和数学模型的同时 ,具体研究了模糊分析设计在油气储量产能预测中的应用 .通过多因素关联度分析导出影响产能开发的因素 ,从主到次依次为 :渗透率、油层厚度、加砂强度、加砂量、孔隙度等     

西北工业发展滞后的数量分析及调整对策

运用统计资料，从工业化基础、工业投入、工业内部结构、工业中非国有经济所占比重、工业的外向性等多个方面，分析了西北地区工业自改革开放以来整体下降的原因，说明工业增长滞后、工业效益滑坡是影响西北经济发展水平的重要因素。提出了在新的外部条件下，调整和优化西北地区工业结构的设想。     

中老年女子服装成衣规格设计--提高服装体型覆盖面的研究

为使尽可能多的中老年女子能根据自己的体型选购到合体的服装，统计分析了中老年女子的人体体型数据，以身胸比来进行体型分类，并在此基础上运用二维区间概率分析方法，制订出对生产具有实用价值的中老年女子合体服装规格参考表，为中老年女子服装的生产提供参考依据。     

HACCP在搅拌型番茄酸奶生产工艺中的应用

将危害分析与关键控制点(HACCP)应用于搅拌型番茄酸奶生产中，对其生产过程进行危害分析，确定关键控制点，并对危害进行有效控制，确保食品的安全性。     

轿车制动效能试验数据的回归分析与仿真

针对国产轿车道路试验中的工况控制、试验结果比较以及试验与仿真的对比等问题 ,提出了在制动效能分析中采用试验实测数据回归分析 ,并利用整车简化模型进行仿真估算的方法 ,并依此分析了原车安装防抱死制动系统后的制动效果 .该方法可为国产化轿车安装防抱死制动系统提供一种简易的分析方法