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991.
阐述了深层搅拌桩在长江干堤邱家湾段加固中的运用,从施工过程介绍了质量控制要点.  相似文献   
992.
选用变频器时功能并不是越多越复杂越好,只要按负载的特性,满足使用要求即可,并指出了安装环境对变频器影响及安装时的注意事项.  相似文献   
993.
陆水水库水利信息网络建设的实践与认识   总被引:1,自引:0,他引:1  
结合陆水水库防洪计算机网络系统的设计和建设,给出了适合水库防洪及水利水电中小企业信息网络平台建设的设计原则和实现方法.  相似文献   
994.
家庭农场绿色防控技术政策偏好与补偿意愿   总被引:1,自引:0,他引:1  
高杨  赵端阳  于丽丽 《资源科学》2019,41(10):1837-1848
病虫害绿色防控技术对实现化学农药减量控害和促进农业可持发展具有重要作用。本文以黄淮海平原的371户家庭农场为例,运用选择实验法,在通过事前“暖身”和“披露”来消除排序效应,并采用推断性属性非参与方法对家庭农场忽略的属性进行信息处理的基础上,构建分层贝叶斯广义混合Logit模型,探讨家庭农场对绿色防控技术推广政策的偏好,并估计家庭农场绿色防控技术采纳的平均补偿意愿及各政策属性边际补偿意愿,以便为政府制定更具针对性和可操作性的推广政策,以及合理的补偿金额提供参考依据。研究发现:家庭农场尤其偏好政府对其进行销售、资金和技术支持;在面临相同的推广政策属性组合时,农场主务农年限越短、受教育水平越高、资产状况越充裕和劳动力数量越少的家庭农场,其绿色防控覆盖率增加的可能性越大;家庭农场的平均补偿意愿为99.66元/亩,各政策属性边际补偿意愿从高到低依次为销售支持(14.75元/亩)、信贷支持(13.75元/亩)、技术支持(12.21元/亩)和保险支持(0.27元/亩)。因此,应将推广政策聚焦于销售、资金和技术3个方面;以农场主务农年限短、受教育水平高、资产状况充裕、劳动力数量少的家庭农场为重点推广对象;结合地区各政策支持力度的变化,灵活地调整具体补贴金额。  相似文献   
995.
运用文献法与田野调查法,阐述了城市绿道体育空间与可达性4级圈层体系的特征,分析城市绿道体育彰显公平和谐,影响民众日常生活的文化融入;概述了亚健康、老年化休闲空间需求和社会世俗化对公共性漠视的现状,从多个层面建构与分析了绿道体育的社会控制功能"金字塔"模式,以及城市社会需求满足与绿道体育参与程度的递进关系,系统解释了城市绿道体育的社会控制基本逻辑。  相似文献   
996.
IntroductionIt is unclear what is the best strategy for applying patient-based real-time quality control (PBRTQC) algorithm in the presence of multiple instruments. This simulation study compared the error detection capability of applying PBRTQC algorithms for instruments individually and in combination using serum sodium as an example.Materials and methodsFour sets of random serum sodium measurements were generated with differing means and standard deviations to represent four simulated instruments. Moving median with winsorization was selected as the PBRTQC algorithm. The PBRTQC parameters (block size and control limits) were optimized and applied to the four simulated laboratory data sets individually and in combination.ResultsWhen the PBRTQC algorithm were individually optimized and applied to the data of the individual simulated instruments, it was able to detect bias several folds faster than when they were combined. Similarly, the individually applied algorithms had perfect error detection rates across different magnitudes of bias, whereas the error detection rates of the algorithm applied on the combined data missed smaller biases. The performance of the individually applied PBRTQC algorithm performed more consistently among the simulated instruments compared to when the data were combined.DiscussionWhile combining data from different instruments can increase the data stream and hence, increase the speed of error detection, it may widen the control limits and compromising the probability of error detection. The presence of multiple instruments in the data stream may dilute the effect of the error when it only affects a selected instrument.  相似文献   
997.
Abstract

The transformation of library metadata encoded in MARC to linked data will enable libraries to participate in the Semantic Web. This transformation, however, will be an iterative development dependent upon community-based decisions. The PCC, as a community-based organization, is ideally positioned to lead this transformation. As PCC guides this transition, three broad areas must be resolved: the conversion of legacy data to linked data, the use of identifiers to support controlled headings, and the transformation of current workflows to linked-data counterparts. By embracing the Web as a community, PCC can confirm its relevance in a complex web of global data.  相似文献   
998.
ABSTRACT

Many museums are housed in historic buildings, sometimes the building itself is part of the museum collection. Creating a stable environment by providing a nearly constant temperature and relative humidity at correct levels decreases the risk of object degradation. Maintaining this steady indoor environment, however, increases energy consumption and risks to the historic building. Museum display cases offer a solution to the mitigation of risks to which valuable objects may be subjected by providing an extra layer of protection to indoor climate fluctuations. The Anne Frank House is a historic house museum located in Amsterdam. The museum has undergone several renovations in the last years to deal with an increase in the number of visitors to over 1.2 million a year. The original diaries and other documents of Anne Frank are permanently on display in the Anne Frank House. With the recent refurbishment the possibility arose to design a new state-of-the-art display case. This study presents the results of the experimental research related to the design, performed in-situ. The temperature and relative humidity in the new exhibition space and inside the new display cases were monitored to gain insight into the hygrothermal behavior of these controlled environments. A complementary numerical study was performed to investigate effects of dynamic climate control of the exhibition gallery and climate conditions in the display case under various circumstances. Four main conclusions are presented in this paper. The investigated display case design is able to provide a stable relative humidity environment by means of silica gel, while using an active box-in-box climate control system to create stable temperature conditions. The inner case temperature depends on the temperature supplied by the display case air handling unit. Protocols must be in place in case of malfunction or failure of the climate control system of the display case. The air handling unit of the case needs to be shut off to create a passive environment for the objects on display until necessary actions are taken. Exhibition gallery set points can be less stringent when susceptible museum objects are on display in the display case. The environments are separated and provide an opportunity for energy saving set point strategies. The last conclusion drawn is that the numerical study provides valuable insight into imposing dynamic control of set points for temperature and relative humidity in the exhibition gallery and the effect on the display case environment.  相似文献   
999.
ABSTRACT

To maintain the accuracy of squash shots under varying conditions, such as the oncoming ball’s velocity and trajectory, players must adjust their technique. Although differences in technique between skilled and less-skilled players have been studied, it is not yet understood how players vary their technique in a functional manner to maintain accuracy under varying conditions. This study compared 3-dimensional joint and racket kinematics and their variability between accurate and inaccurate squash forehand drives of 9 highly skilled and 9 less-skilled male athletes. During inaccurate shots, less-skilled players hit the ball with a more open racket, demonstrating a difference in this task-relevant parameter. No joint kinematic differences were found for accuracy for either group. Coordinated joint rotations at the elbow and wrist both displayed a “zeroing-in” effect, whereby movement variability was reduced from the initiation of propulsive joint rotation to a higher consistency at ball-impact; potentially highlighting the “functionality” of the variability prior to the impact that enabled consistent task-relevant parameters (racket orientation and velocity) under varying conditions. Further, highly skilled players demonstrated greater consistency of task-relevant parameters at impact than less-skilled players. These findings highlight the superior ability of highly skilled players to adjust their technique to achieve consistent task-relevant parameters and a successful shot.  相似文献   
1000.
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