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51.
《组织行为杂志》2017,38(5):615-628
Proper scale development and validation provide the necessary foundation to facilitate future quantitative research in the organizational sciences. Using the framework provided by the Researcher's Notebook , the purpose of this study is twofold. First, we present a modern summary of best practice procedures for scale development, reliability analysis, and validity analysis. Second, we explain and illustrate these best practice procedures by describing each procedure in the context of developing and psychometrically analyzing a new Character Strength Inventory (CSI). Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
52.
马彦峰  张勇 《环境保护科学》2010,36(1):61-63,68
环境监测是为了获得准确的环境信息数据,以便为环境评价、环境管理和环境治理提供依据。监测数据是否具有代表性,必须通过数据分析才能确定。文章通过介绍对监测数据的精密性、准确性和合理性检验,论述了监测数据的代表性。  相似文献   
53.
基于DEA-Malmquist的我国城市物质代谢效率评价   总被引:1,自引:1,他引:0  
运用数据包络分析与麦氏指数(DEA-Malmquist),从"技术效率"、"技术变动效率"和"全要素生产率"三个方面,对我国34个城市从2005年到2007年的物质代谢效率进行实证分析,结果表明:物质代谢效率的总体水平不高,被评估的34个城市中有19个城市在评价期间是无效率的,主要分布在西部地区;并且整体而言,"全要素生产率"和"技术变动效率"要优于"技术效率";结果还表明:34个城市物质代谢的"技术效率"普遍处于中等水平,没有呈现出明显的空间分布差异,但是"技术变动效率"则在长三角地区的城市中体现出较为明显的优势,最后,提出了针对性的建议。  相似文献   
54.
利用2005~2007年我国稻田N2O排放通量的田间原位测定资料和国际上其它地区稻田N2O报道结果,对作者建立的不同水分管理方式下水稻生长季N2O排放估算模型进行了验证. 结果表明,持续淹水稻田N2O排放的拟合结果与其他地区淹水稻田N2O通量值相一致. 淹水-烤田-淹水的水分管理方式下,稻田N2O排放的拟合值接近于国际上同类研究结果. 淹水-烤田-淹水-湿润灌溉的水分管理方式下,稻田N2O排放的估算模型对田间原位测定资料有很好的适切性. 为了检验模型输入参数的可信度,将本研究建立的有关我国水稻生产的相关资料数据库与以往研究报道结果进行了比较,结果表明,两者具有高度的一致性. 数据库资料表明,在20世纪50~70年代间,持续淹水稻田占20%~25%,大约75%~80%的稻田采用淹水-烤田-淹水的水分管理方式. 在20世纪80~90年代间,采用持续淹水,淹水-烤田-淹水和淹水-烤田-淹水-湿润灌溉水分管理方式的稻田分别约占12%~16%、 77%和7%~12%. 20世纪50年代水稻生长季平均每季总施氮量为87.49 kg·hm-2,而90年代平均为224.64 kg·hm-2. 其中,化学氮肥的施用量从20世纪50年代的37.4 kg·hm-2增加到了90年代的198.8 kg·hm-2,分别占水稻生长季氮输入总量的43%和88%. 在20世纪50~70年代间有机氮的输入量相对比较稳定,平均变幅在45.2~48.2 kg·hm-2之间,随后逐步降低,有机肥料氮占氮输入总量的比例从20世纪50年代的52%降低到了90年代的9%. 作物残体N输入量从20世纪50年代的4.9 kg·hm-2增加到了80年代的6.3 kg·hm-2. 20世纪50~70年代水稻生长季氮肥施用量具明显的空间变异性,而80~90年代间其空间变异较小. 模型验证和输入参数检验的结果表明,该模型能较好地模拟我国不同水分管理方式下的稻田N2O直接排放量.  相似文献   
55.
浅谈环境信息中的GIS技术和中介数据   总被引:5,自引:0,他引:5  
介绍了在环境信息系统中GIS技术所具有的功能和中介数据的作用及其规范化问题;并结合中国省级环境决策支持系统的开发,介绍了它们在环境信息中的使用。   相似文献   
56.
The Eulerian atmospheric tracer transport model MATCH (Multiscale Atmospheric Transport and Chemistry model) has been extended with a Lagrangian particle model treating the initial dispersion of pollutants from point sources. The model has been implemented at the Swedish Meteorological and Hydrological Institute in an emergency response system for nuclear accidents and can be activated on short notice to provide forecast concentration and deposition fields.The model has been used to simulate the transport of the inert tracer released during the ETEX experiment and the transport and deposition of 137Cs from the Chernobyl accident. Visual inspection of the results as well as statistical analysis shows that the extent, time of arrival and duration of the tracer cloud, is in good agreement with the observations for both cases, with a tendency towards over-prediction for the first ETEX release. For the Chernobyl case the simulated deposition pattern over Scandinavia and over Europe as a whole agrees with observations when observed precipitation is used in the simulation. When model calculated precipitation is used, the quality of the simulation is reduced significantly and the model fails to predict major features of the observed deposition field.  相似文献   
57.

Introduction

The purpose of this study was to analyze linked crash and hospital data to determine the effect that enactment of a standard enforcement safety belt law in Ohio would have on hospital charges and direct medical costs due to motor-vehicle crashes, focusing on the impact to the state's Medicaid system.

Method

The linkage and analysis was conducted as part of the Ohio Crash Outcome Data Evaluation System (CODES) program. Current safety belt usage in Ohio stands at 82% with its secondary enforcement safety belt law.

Results

Assuming an increase in usage to 92% through standard enforcement, over $15.3 million in medical costs to Medicaid for injuries that occur in a single year could be prevented over a 10-year period. Cumulative savings could reach more than $91.2 million during the 10-year period. In addition, 161 fatalities could have been prevented in one year had all unbelted occupants who sustained a fatal injury instead chosen to wear their safety belt.

Summary and Impact on Industry

Clearly, substantial progress can be made in reducing the number of deaths and injuries, as well as medical costs associated with motor-vehicle crashes, by strengthening safety belt laws and increasing safety belt usage in Ohio.  相似文献   
58.
为了系统的评价煤矿安全投入效率,采用DEA(数据包络分析)方法,选取我国1991~2010年煤矿安全投入产出数据构建DEA模型,其中煤矿安全投入指标为采煤机械化程度、工程技术人员百分比、颁布煤矿安全法规数和行业标准,产出指标为煤矿百万吨死亡率。根据构建的DEA模型对每年的效率进行分析和评价,并提出建议。同时运用Malmquist指数(全要素生产力指数)对煤矿安全投入效率进行分解研究。研究结果表明,从静态上看,我国仅有1993年和2010年当年的煤矿安全投入和产出都达到了最优状态,并且随着煤矿安全投入逐年增加,煤矿安全投入技术效率、纯技术效率、规模效率逐年提升。从动态上看,我国煤矿安全投入Malmquist指数的提高对技术的依赖很明显,无论是技术进步还是技术效率的提高都会相应的提高Malmquist指数。  相似文献   
59.
The consequence modelling package Phast examines the progress of a potential incident from the initial release to the far-field dispersion including the modelling of rainout and subsequent vaporisation. The original Phast discharge and dispersion models allow the released substance to occur only in the vapour and liquid phases. The latest versions of Phast include extended models which also allow for the occurrence of fluid to solid transition for carbon dioxide (CO2) releases.As part of two projects funded by BP and Shell (made publicly available via CO2PIPETRANS JIP), experimental work on CO2 releases was carried out at the Spadeadam site (UK) by GL Noble Denton. These experiments included both high-pressure steady-state and time-varying cold releases (liquid storage) and high-pressure time-varying supercritical hot releases (vapour storage). The CO2 was stored in a vessel with attached pipework. At the end of the pipework a nozzle was attached, where the nozzle diameter was varied.This paper discusses the validation of Phast against the above experiments. The flow rate was predicted accurately by the Phast discharge models (within 10%; considered within the accuracy at which the BP experimental data were measured), and the concentrations were found to be predicted accurately (well within a factor of two) by the Phast dispersion model (UDM). This validation was carried out with no fitting whatsoever of the Phast extended discharge and dispersion models.  相似文献   
60.
In this study, an integrated “Health, Safety, and Environment (HSE)” and maintenance systems are presented. Multivariate analysis is used for continuous performance assessment and improvement of these systems. The two subjects of “Maintenance System” and “HSE” have been individually investigated several times in different studies. However, few studies have been done to integrate these two systems and provide an integrated system for their implementation. This study evaluates current maintenance and HSE systems of a Gas Transmission Unit by Data Envelopment Analysis (DEA) and Principal Component Analysis (PCA). Moreover, decision making units (DMUs) are examined and ranked. Employees are considered as DMUs. This is done through investigating and measuring their efficiencies and identifying the inefficient and less-efficient units. Since an increase in the number of inputs does not lead to an increase in the number of outputs with the same scale, an output-oriented DEA with a Variable Returns to Scale (VRS) is used. The Fuzzy DEA (FDEA) is also used in this research to decrease uncertainty existing in qualitative indicators and human error. Finally, suggestions are given to improve those DMUs. The managers and employees of the gas transmission unit constitute the statistical population of the study. To achieve the objectives of this study, standard questionnaires with respect to HSE and Maintenance system are completed by operators. The proposed approach would help policy makers and top managers of Gas Transmission Company to have a more comprehensive and thorough understanding the working conditions with respect to the maintenance and HSE features.  相似文献   
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