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卫星地面站角坐标调整实验的再研究
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作者 郑立坤 刘琦 《实验室研究与探索》 CAS 2004年第9期68-69,74,共3页
随着我国广播电视事业的日益发展,"村村通"的进一步实现,卫星接收已越来越普及,社会急需大量的有线电视知识和技术人才。实验利用"废旧"设备,采用极其简便的方法和极为普通的工具(量角器和罗盘),进行卫星地面站角... 随着我国广播电视事业的日益发展,"村村通"的进一步实现,卫星接收已越来越普及,社会急需大量的有线电视知识和技术人才。实验利用"废旧"设备,采用极其简便的方法和极为普通的工具(量角器和罗盘),进行卫星地面站角坐标的调整实验研究。 展开更多
关键词 卫星地面站 角坐标 调整实验 有线电视
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煤/气混燃锅炉再热汽温偏差调整实验
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作者 闫俊伏 赵学斌 《热力发电》 CAS 北大核心 2019年第2期108-113,共6页
为了研究混燃高炉煤气对炉膛上部烟气速度偏差的影响,对不同高炉煤气热量混燃比工况进行了数值模拟,得到炉膛上部烟气速度偏差随着高炉煤气热量混燃比的增加而增大。针对混燃高炉煤气引起的再热汽温偏差问题进行了分离燃尽风水平摆角优... 为了研究混燃高炉煤气对炉膛上部烟气速度偏差的影响,对不同高炉煤气热量混燃比工况进行了数值模拟,得到炉膛上部烟气速度偏差随着高炉煤气热量混燃比的增加而增大。针对混燃高炉煤气引起的再热汽温偏差问题进行了分离燃尽风水平摆角优化调整实验,得到了最佳摆角组合。结果表明:分离燃尽风(SOFA)的1号、2号、3号、4号喷口水平偏转角度依次为–7.5°、+7.5°、+7.5°、–7.5°时,再热汽温偏差由17.10℃降低到了2.55℃,再热汽温为536.4℃,主蒸汽汽温偏差为4.15℃,主蒸汽温度为538.7℃。 展开更多
关键词 高炉煤气 煤/气混燃 烟气速度 再热汽温 偏差 调整实验 分离燃尽风 水平摆角
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YTQ-7氧气调节器性能参数调整分析与实验验证 被引量:2
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作者 邹念东 张宝平 +3 位作者 王定生 肖华军 刘晓鹏 臧斌 《航空科学技术》 2011年第5期45-48,共4页
通过对YTQ-7氧气调节器供氧浓度调节原理的分析,说明调整氧浓度调节机构后,在高空输入富氧情况下,可以达到输入纯氧时的供氧浓度要求。经测试并对比分析YTQ-7氧气调节器调整前后供氧性能参数实验数据,验证调整后的氧气调节器供氧性能能... 通过对YTQ-7氧气调节器供氧浓度调节原理的分析,说明调整氧浓度调节机构后,在高空输入富氧情况下,可以达到输入纯氧时的供氧浓度要求。经测试并对比分析YTQ-7氧气调节器调整前后供氧性能参数实验数据,验证调整后的氧气调节器供氧性能能够满足不同高度下供氧浓度生理学要求。 展开更多
关键词 氧气调节器 模拟分子筛供氧 性能参数:调整分析:实验验证
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浅谈职业技术教育微生物实验课的改革 被引量:7
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作者 王艳 《微生物学杂志》 CAS CSCD 2007年第5期111-112,共2页
微生物学是一门实践性和应用性很强的学科,它作为与多种专业有关的专业基础课,具有广泛的普及性和重要性。鉴于职业技术教育本身的特点,根据近年经验对实验教学提出一些看法,以供参考。
关键词 实验改革课时调整职业技能考核
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利用教师blog开展现代教育技术实验内容的探索
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作者 王瑜 陈润荣 《中国现代教育装备》 2010年第9期57-58,共2页
现代教育技术实验由于受到诸多因素的影响,无法很好地开展,本文介绍了利用教师blog开展该门课程实验的做法—建构学习环境,调整实验内容。让学生通过本门课程的学习尽可能达到中小学教师教育技术能力标准,并兼顾提高学生ICT技能,提高学... 现代教育技术实验由于受到诸多因素的影响,无法很好地开展,本文介绍了利用教师blog开展该门课程实验的做法—建构学习环境,调整实验内容。让学生通过本门课程的学习尽可能达到中小学教师教育技术能力标准,并兼顾提高学生ICT技能,提高学生建构学习环境的能力。对现代教育技术实验设备不够完善、网络技术支持相对薄弱、学生信息素养不高的地区提供了一个参考。 展开更多
关键词 教师BLOG 建构学习环境 调整实验内容 认知工具
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神经网络专家系统在铁路货车空重车自动调整装置试验台上的应用
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作者 方瑞凤 《铁道技术监督》 2004年第5期29-30,共2页
根据专家系统基本原理,结合模糊理论、神经网络理论,建立了货车空重车自动调整装置试验台的试验监控系统,判断试验台试验过程并指示操作者对试验台进行合理的操作;同时建立了试验故障诊断系统,对故障阀进行故障分析和预测。
关键词 神经网络专家系统 铁路货车 空重车自动调整装置实验 模糊推理 铁路运输
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CARS相邻能级选择激发最佳可调参数的设计
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作者 孟芳芳 丛爽 《量子电子学报》 CAS CSCD 北大核心 2011年第5期513-521,共9页
在其他实验参数都确定的情况下,通过进一步调整泵浦光、斯托克斯光和探测光的相位函数,计算对称与反对称伸缩振动的光极化强度峰值之比为最优,来实现甲醇溶液中CH_3对称和反对称伸缩振动相干反斯托克斯拉曼光谱(CARS)的选择激发。采用Si... 在其他实验参数都确定的情况下,通过进一步调整泵浦光、斯托克斯光和探测光的相位函数,计算对称与反对称伸缩振动的光极化强度峰值之比为最优,来实现甲醇溶液中CH_3对称和反对称伸缩振动相干反斯托克斯拉曼光谱(CARS)的选择激发。采用Silberberg提出的控制方法,通过参数调整实验,总结了各可调参数对选择激发效果的影响,并根据相关理论,定性分析了该控制方法的内部控制机理及最佳可调参数的范围,最后总结实现相邻能级选择激发的参数调控方法。 展开更多
关键词 量子光学 选择激发 参数调整仿真实验 相干反斯托克斯拉曼散射
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Evolutionary Pattern and Effect of Administrative Division Adjustment During Urbanization of China:Empirical Analysis on Multiple Scales 被引量:4
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作者 YU Hu DENG Yu XU Shan 《Chinese Geographical Science》 SCIE CSCD 2018年第5期758-772,共15页
The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively d... The adjustment of administrative divisions is one of the important factors guiding China's urbanization, which has profound economic and social effects for regional development. In this paper, we comprehensively describe the process of the adjustment of administrative divisions at provincial and municipal levels in China and summarize the effects on the basic structure and patterns of the spatial development. We quantitatively assess the effects on fields such as urbanization and social economy through the use of multidimensional scaling. The results show that: 1) Upgrading county to municipality(or city-governed district) is the main way of adjusting the administrative divisions. It is also an important factor in the spatial differentiation of interprovincial urbanization. China's population urbanization can be divided into four patterns including interprovincial migration, provincial migration, natural growth, and growth caused by the adjustment of administrative divisions, which is also the main reason for the increased Chinese urbanization rate at the provincial level. 2) Taking the city of Beijing as an example, we generalize five adjustment patterns made to administrative divisions: the set-up of sub-districts, the set-up of regional offices, the upgrading of townships to sub-districts, the upgrading of townships to towns, and the set-up of towns and the addition of new regional offices. We summarize the municipal urban spatial structure, including the sub-district office area in the central urban area, the regional office area in the new urban area, the mixed area of villages, towns, and sub-district offices in the suburb area, and the township area in the outer suburb area. 3) The adjustment of administrative divisions triggers a significant circulative accumulation effect, resulting in the spatial locking of population and industrial agglomeration. It affects the evolution of the urban spatial form and plays an important role in shaping the urban spatial structure to move to the characteristic of multicenter. In general, the adjustment of administrative divisions was an important factor affecting the inflated statistical level of urbanization and also an important driving force for the evolution of Chinese urban spatial organization structure. 展开更多
关键词 administrative division adjustment evolutionary structure effect evaluation multidimensional scaling URBANIZATION China
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药物在正辛醇-水体系分配系数估算方法的研究 被引量:2
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作者 吴义辉 区荼 尹洁安 《广东药学》 1998年第4期14-15,共2页
估算有机物在正辛醇 -水体系分配系数对数值 (logp)的方法很多 ,本文应用Leo基团常数法和最近开发的AFC(atom /fregmentcontribution)方法估算结构复杂的药物分子的logp值。计算结果与实验值比较 ,其平均绝对偏差为 0 32~ 0 2 4logp... 估算有机物在正辛醇 -水体系分配系数对数值 (logp)的方法很多 ,本文应用Leo基团常数法和最近开发的AFC(atom /fregmentcontribution)方法估算结构复杂的药物分子的logp值。计算结果与实验值比较 ,其平均绝对偏差为 0 32~ 0 2 4logp单位。 展开更多
关键词 分配系数 基团常数法 实验调整
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浙江大学求是公司教学仪器产品介绍
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作者 郑群 张伟 《电气电子教学学报》 2000年第3期111-114,共4页
关键词 电力电子教学仪器 交直流调整系统实验装置
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浅谈多级放大器设计中的几个问题
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作者 陈伟 《电子测试》 2013年第10X期30-31,共2页
在一些电子设备中,常常要求放大电路的输出级能够带动一定的负载。因而要求放大电路有足够大的输出功率,因此对功率放大电路有以下几个要求:(1)根据负载要求,提供足够的输出功率;(2)具有较高的效率;(3)尽量减小非线性失真。一个多级放大... 在一些电子设备中,常常要求放大电路的输出级能够带动一定的负载。因而要求放大电路有足够大的输出功率,因此对功率放大电路有以下几个要求:(1)根据负载要求,提供足够的输出功率;(2)具有较高的效率;(3)尽量减小非线性失真。一个多级放大器,无论如何复杂,总是由各种单级放大器组成的。要设计一个晶体三极管多级放大器,一般采用定性分析、定量计算和实验调整三者结合的设计方法。没有理论上的定性分析与定量估算,将是盲目的实践;但是,由于晶体管参数分散性大的特点,分析和计算不可能十分精确,只有通过实验调整才能使之完善起来。 展开更多
关键词 功率 效率 失真 定性分析 定量计算 实验调整
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What if the "Gold Standard" Can't Be Realized? Propensity Scoring to Adjust for Attrition in Random Experiments
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作者 Michael A. Lewis 《Sociology Study》 2011年第1期75-81,共7页
When it comes to evaluating the effectiveness of interventions, the random experiment is considered the "gold standard". Randomization is considered the gold standard because it provides a way of decreasing the chan... When it comes to evaluating the effectiveness of interventions, the random experiment is considered the "gold standard". Randomization is considered the gold standard because it provides a way of decreasing the chance that systematic differences, other than type of intervention, will be obtained between treatment and control groups. What has received little attention in the literature, however, is the fact that even with random assignment researchers may end up facing problems similar to those faced with data from a study that did not use randomization. This is because attrition may result in the values of potentially confounding variables no longer being "balanced" between (or among) the groups under investigation. This means that in order to estimate the effect of the treatment, one must find some way of adjusting for these potential confounders. Although multiple regression modeling is the way social science researchers typically control for the effects of potentially confounding variables, this paper argues that a modification of multiple regression modeling that uses propensity scores, under some conditions, may provide more parsimonious and better fitting models. 展开更多
关键词 Multiple regression propensity scoring logistic regression attrition in random experiments
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优化涂装工艺,降低涂装成本 被引量:1
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作者 曹晓根 《北京汽车》 2011年第3期30-32,共3页
通过对汽车涂装主要成本组成部分的分析,从制订和改进涂装工艺的角度阐述了几种降低涂装成本的思路,并引申了其他可以降低成本的工位或材料。
关键词 降低涂装成本 实验调整 过滤棉更换 材料利用率
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Adjusted Empirical Likelihood Estimation of Distribution Function and Quantile with Nonignorable Missing Data 被引量:1
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作者 DING Xianwen TANG Niansheng 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2018年第3期820-840,共21页
This paper considers the estimation problem of distribution functions and quantiles with nonignorable missing response data. Three approaches are developed to estimate distribution functions and quantiles, i.e., the H... This paper considers the estimation problem of distribution functions and quantiles with nonignorable missing response data. Three approaches are developed to estimate distribution functions and quantiles, i.e., the Horvtiz-Thompson-type method, regression imputation method and augmented inverse probability weighted approach. The propensity score is specified by a semiparametric expo- nential tilting model. To estimate the tilting parameter in the propensity score, the authors propose an adjusted empirical likelihood method to deal with the over-identified system. Under some regular conditions, the authors investigate the asymptotic properties of the proposed three estimators for distri- bution functions and quantiles, and find that these estimators have the same asymptotic variance. The jackknife method is employed to consistently estimate the asymptotic variances. Simulation studies are conducted to investigate the finite sample performance of the proposed methodologies. 展开更多
关键词 Adjusted empirical likelihood distribution estimation exponential tilting model nonig-norable missing data quantile.
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Ocean satellite data assimilation experiments in FIO-ESM using ensemble adjustment Kalman filter 被引量:4
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作者 CHEN Hui YIN Xun Qiang +1 位作者 BAO Ying QIAO Fang Li 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第3期484-494,共11页
Using Ensemble Adjustment Kalman Filter(EAKF), two types of ocean satellite datasets were assimilated into the First Institute of Oceanography Earth System Model(FIO-ESM), v1.0. One control experiment without data ass... Using Ensemble Adjustment Kalman Filter(EAKF), two types of ocean satellite datasets were assimilated into the First Institute of Oceanography Earth System Model(FIO-ESM), v1.0. One control experiment without data assimilation and four assimilation experiments were conducted. All the experiments were ensemble runs for 1-year period and each ensemble started from different initial conditions. One assimilation experiment was designed to assimilate sea level anomaly(SLA); another, to assimilate sea surface temperature(SST); and the other two assimilation experiments were designed to assimilate both SLA and SST but in different orders. To examine the effects of data assimilation, all the results were compared with an objective analysis dataset of EN3. Different from the ocean model without coupling, the momentum and heat fluxes were calculated via air-sea coupling in FIO-ESM, which makes the relations among variables closer to the reality. The outputs after the assimilation of satellite data were improved on the whole, especially at depth shallower than 1000 m. The effects due to the assimilation of different kinds of satellite datasets were somewhat different. The improvement due to SST assimilation was greater near the surface, while the improvement due to SLA assimilation was relatively great in the subsurface. The results after the assimilation of both SLA and SST were much better than those only assimilated one kind of dataset, but the difference due to the assimilation order of the two kinds of datasets was not significant. 展开更多
关键词 Earth system model Ocean satellite data Ensemble adjustment Kalman filter Data assimilation
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