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1.
制造业是我国国民经济的支柱产业,但也是环境污染物排放的主要来源、能源消耗主体和温室气体排放大户。制造系统高能耗、高物耗、高碳排放的加工过程是造成制造业碳排放量大的重要原因。生产单元作为制造系统的加工的主体,其碳排放量的核算是确定整个制造系统乃至制造业碳排放总量的关键。本文首先对生产单元的原材料、电能、辅助物料及废屑处理所引起的碳排放进行分析,确定生产单元的碳排放源;其次,产品合格率的不同会造成生产单元输入及输出的成品/半成品数量的差异,进而影响生产单元单位产品的碳排放量,在此基础上,综合考虑了原材料、电能、辅助物料及废屑处理的碳排放情况,构建了给定工艺流程下生产单元碳排放核算模型。最后,结合一汽车排气装置加工实例,分别核算加工过程中九个生产单元的碳排放量,验证了模型的可行性。 相似文献
2.
《Risk analysis》2018,38(8):1634-1655
The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated. 相似文献
3.
ABSTRACTPolicymakers and researchers are concerned with whether joint physical custody (JPC) produces better outcomes for children than sole custody. Although several review articles summarizing up to 61 empirical articles demonstrate very positive answers, many of the research designs used compromise the ability to claim that it is JPC per se—and not selection effects—that causes the effect. We discuss several research design issues, such as propensity score analysis, that can more powerfully probe the question of causality. Some studies have already been conducted employing these strategies and more are recommended and likely to soon be forthcoming. On the basis of this comprehensive review we conclude that JPC probably does cause benefits to children on average, and that social scientists can now provisionally recommend rebuttably presumptive JPC to policymakers. 相似文献
4.
Gena A. Rowlands 《Journal of divorce & remarriage》2019,60(4):316-331
The Rowlands Parental Alienation Scale (RPAS) was administered to 592 parents along with measures of convergent and discriminant validity. The scale was designed to capture the eight domains of parental alienating behavior posited in the literature. Factor analysis extracted only six factors, one of which was not included in the original eight: (a) campaign of denigration towards the alienated parent, (b) the independent thinker phenomenon, (c) reflexive support, (d) presence of borrowed scenarios, (e) spread of animosity to extended family, and (f) lack of positive affect towards the alienated parent. Parents who reported either that a court evaluation or court findings had confirmed the presence of parental alienation scored significantly higher on all six RPAS factors as well as on the overall RPAS score. 相似文献
5.
Jen-Hao Chen 《Journal of applied statistics》2019,46(4):725-736
This paper presents a simple and robust method for obtaining a comprehensive understanding of the joint period and radius distribution in Kepler exoplanets. The proposed method is based on particle swarm optimization and bivariate Normal Inverse Gaussian distribution. Furthermore, in the construction of the probability density function, this study selects planet-host stars with the GK-type. The injecting approach is also employed to solve the survey completeness of sample. The resulting occurrence rate of Earth analogs is 0.025 with a 95% bootstrap confidence interval between 0.023 and 0.032. 相似文献
6.
A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set. 相似文献
7.
8.
Belinda Crissman 《The Australian journal of social issues》2019,54(3):245-266
People with serious mental disorders (PSMDs) are overrepresented both in prison deaths and during fatal encounters with the police in the community (deaths after police contact, DAPC). To identify common factors present across cases of who died during contact with the criminal justice system in Queensland, publicly available coroners reports were analysed (N = 38). The findings of the study indicated psychosis and mood disorders were the most common diagnosis in incarcerated PSMD deaths, and suicide was the most common cause of death for incarcerated PSMDs. Within incarcerated settings, access to healthcare records, medication compliance, risk assessment and monitoring, and safe housing of at‐risk prisoners may be potential areas to explore with regard to prevention. Similarly, PSMD DAPCs were more likely to be experiencing mood or psychosis disorders than other forms of mental disorder, and suicide and police shootings were the most common causes of death. In PSMD DAPC, inadequate mental health access, treatment noncompliance and comorbid substance use were included as potential areas that could direct research efforts toward prevention. 相似文献
9.
In this paper, we investigate the k-nearest neighbours (kNN) estimation of nonparametric regression model for strong mixing functional time series data. More precisely, we establish the uniform almost complete convergence rate of the kNN estimator under some mild conditions. Furthermore, a simulation study and an empirical application to the real data analysis of sea surface temperature (SST) are carried out to illustrate the finite sample performances and the usefulness of the kNN approach. 相似文献
10.