中国碳强度承诺的含义、特点与履行

中国碳强度承诺是中国的国家温室气体中期减排目标。中国碳强度只统计绝大部分CO2排放,且不扣除碳汇。中国碳强度承诺具有正当性、严格性和国内约束性,也具有一定程度的模糊性。中国降低碳强度的重点是控制化石燃料燃烧引起的CO2排放,为此必须节约能源和降低能源排放因子。     

经济发展与碳减排分析

全球气候变化和碳减排对于发达国家和发展中国家具有不同的意义,对于发展中国家而言,其首要任务是适应和发展。基础设施建设和城市化是实现发展的必由之路,在现有技术条件下,这也意味着经济发展必须经过一个碳排放快速增加的阶段,而中国正处于这一发展阶段。中国在2000年以前在碳减排方面的出色表现很大程度上是市场化改革带来的制度红利所致,今后继续保持碳强度下降的关键在于技术能力的提高。     

我国东北地区城镇化与节约型社会建设之间的耦合协调发展度研究

在建立评价指标体系对我国东北地区节约型社会的建设现状进行评价分析的基础上,结合城镇化水平的相关数据,对其城镇化建设与节约型社会建设之间的耦合协调发展度做一尝试性的分析和探讨,并提出相应的对策与建议。     

Development of an urban intensity index to facilitate urban ecosystem studies in Trinidad and Tobago

Urban ecosystems, considered centres of economic, social and cultural development, face a multitude of environmental and socio-economic challenges, which impact on quality of life. Effective management of the urbanization process is believed critical to improving quality of life and realizing sustainable development. The ecosystem perspective provides a holistic approach, needed to address the complexly interconnected issues, which arise from urban development. Central to the mapping and characterization of urban ecosystems is the delineation of their boundaries, which are made less transparent by growing urbanization. This exposes the limitations of a dichotomous approach. An urban intensity index is a critical tool which supports urban ecosystem studies by facilitating analysis of effects along the urban–rural gradient. In this study, Urban Intensity is estimated and ranked from most to least intense for communities across Trinidad and Tobago, using multivariate statistical analysis of physical data from the built environment. This statistically validated index, designed for Trinidad and Tobago, should have wider applicability to other disciplines and countries.     

A quantile-based study on ageing intensity function

Jiang, Ji, and Xiao (2003 Jiang, R., P. Ji, and X. Xiao. 2003. Aging property of unimodal failure rate models. Reliability Engineering and System Safety 79(1):113–6.[Crossref], [Web of Science ®] , [Google Scholar]) has introduced a quantitative measure known as the ageing intensity function for evaluating the ageing properties of a component/system. In recent years, there has been a great interest on the study of quantile function, an equivalent alternative to the distribution function approach. Unlike the distribution function approach, the quantile method possess some unique properties (see Gilchrist 2000 Gilchrist, W. 2000. Statistical modelling with quantile functions. Boca Raton, Florida: Chapman and Hall/CRC.[Crossref] , [Google Scholar], Nair, Sankaran, and Balakrishnan 2013 Nair N. U., P. G. Sankaran, N. Balakrishnan. 2013. Quantile-based reliability concepts. In: Quantile-Based Reliability Analysis. Statistics for Industry and Technology. New York, NY: Birkhäuser.[Crossref] , [Google Scholar]). Motivated with this, in the present paper we introduce a quantile-based ageing intensity function and study its various ageing properties. We also study some stochastic comparison of random variables based on the proposed measure.     

基于投入产出非线性优化的制造业完全能耗强度情景分析

当前,环境污染仍为中国最突出的问题之一,而降低制造业完全能耗强度是减少消耗及污染的重要途径。本文基于投入产出非线性优化理论,以制造业完全能耗强度最小为目标,并以18个行业最终需求为决策变量,构建了一个完全能耗强度非线性优化模型,特引入了进出口系数等约束条件,并基于已有投入产出表等数据,预测调整模型的相关系数。在此基础上,设计了三个方案与两个情景,并运用粒子群算法求解模型。结果表明:2015年中国制造业完全能耗强度最小值区间为0.7823-0.9048tce/万元,相比2010年,下降率区间为8.9%-21.31%。在高方案情景2下,可实现制造业完全能耗强度降低20%的目标。为实现该目标,应促进中低能耗制造业发展、降低高能耗制造业的完全能耗量、适当提高消费和进口系数并降低投资和出口系数。本文既有利于政府部门制定科学系统的节能减排政策,也有利于深化能源经济与管理理论。     

Information-based thinning of point processes and its application to shock models

Thinning of point processes is a useful operation that is implemented in various stochastic models. When the initial point process is the nonhomogeneous Poisson process (NHPP), the thinned processes are also nonhomogeneous Poisson processes independent of each other. The crucial assumption in deriving this result is that the corresponding classification of events is independent of all other events, including the history of the process. However, in practice, this classification is often dependent on the history. In our paper, we define and describe the thinned processes for the history-dependent case using different levels of available information. We also discuss the applications of the obtained general results to the corresponding shocks models.     

Urban African American Pre-Adolescent Social Problem Solving Skills

Summary

The results of two studies focusing on the social problem solving skills of African American preadolescent youth are detailed. In the first study data from a sample of 150 African American children, ages 9 to 11 years, was used to examine the association between type of youth social problem solving approaches applied to hypothetical risk situations and time spent in unsupervised peer situations of sexual possibility. Findings revealed that children with more exposure to sexual possibility situations generated a wider range of social problem solving strategies, but these approaches tended to be unrealistic and ambiguous. Further, there was a positive association between the amount of time spent unsupervised and youth difficulty formulating a definitive response to hypothetical peer pressure situations. Children with less exposure to sexual possibility situations tended to be more aggressive when approaching situations of peer pressure. In the second study, data from a non-overlapping sample of 164 urban, African American adult caregivers and their 9 to 11 year old children was examined in order to explore the associations between child gender, family-level factors including family communication frequency and intensity, time spent in situations of sexual possibility, and youth social problem solving approaches. Results revealed that children were frequently using constructive problem solving and help seeking behaviors when confronted by difficult social situations and that there was a significant relationship between the frequency and intensity of parent child communication and youth help seeking social problem solving approaches. Implications for research and family-based interventions are highlighted.     

港口经济与城市经济系统耦合协调度实证研究

我国正处于港口高速建设和城市迅速发展时期,协调港口和城市功能的关系对提高港口城市的综合能力具有重要意义。在深入分析港城经济系统耦合机理的基础上,采用熵权法选取港口经济与城市经济的耦合元素指标,并以深圳港为例,运用耦合度模型与耦合协调度模型进行实证分析,动态把握港口经济与城市经济的耦合协调状态。研究表明,2000~2011年期间,深圳港口经济与城市经济两大系统的耦合系统程度趋向转好,耦合发展类型由严重不协调衰退向高级协调发展转变,并有向优质协调发展的趋势,体现了两大系统的协同效应。     

冷却剂参数对铣槽喷管低周疲劳寿命的影响

采用有限体积流固耦合计算方法、非线性有限元热结构耦合分析方法和局部应变法研究大面积比铣槽喷管三维再生冷却槽道在循环工作条件下的热结构变形与低周疲劳寿命,并对比分析了冷却剂质量流量与入口温度对铣槽喷管疲劳使用寿命的影响。计算结果表明,铣槽喷管热结构响应呈现复杂的三维效应,应变较大位置主要分布在与肋连接的内衬区域,喷管中部的残余应变量最大;冷却槽道低周疲劳寿命分布和热结构响应基本一致,最小寿命位于喷管中部与肋相连的内衬区域燃气侧;随冷却剂质量流量增加,铣槽喷管低周疲劳寿命不断提高;随冷却剂入口温度增加喷管尾部低周疲劳寿命值不断降低,而喷管中前部的低周疲劳寿命值却不断提高,当冷却剂入口温度为280K左右时,本文的铣槽喷管总体使用寿命达到最大。 