太阳能-土壤源热泵系统在唐山地区适用性研究

简述了太阳能-土壤源热泵系统的研究现状,介绍了太阳能-土壤源热泵系统形式,采用Dest软件对唐山地区的太阳能辐射量情况进行了分析,并对典型建筑的负荷特性进行了模拟分析,论述了太阳能-土壤源热泵系统在唐山地区的适用性。     

太阳能-土壤源热泵系统在唐山地区适用性研究

简述了太阳能-土壤源热泵系统的研究现状,介绍了太阳能-土壤源热泵系统形式,采用Dest软件对唐山地区的太阳能辐射量情况进行了分析,并对典型建筑的负荷特性进行了模拟分析,论述了太阳能-土壤源热泵系统在唐山地区的适用性。     

太阳能-土壤源热泵系统在唐山地区适用性研究

简述了太阳能-土壤源热泵系统的研究现状,介绍了太阳能-土壤源热泵系统形式,采用Dest软件对唐山地区的太阳能辐射量情况进行了分析,并对典型建筑的负荷特性进行了模拟分析,论述了太阳能-土壤源热泵系统在唐山地区的适用性。     

地源热泵——新概念的冷暖空调

地源热泵就是一种能量搬运机。冬天代替锅炉从土壤中取热,以30～40℃的热风向建筑物供暖;夏季替代普通空调向土壤排热,以10℃左右的冷风形式为建筑物制冷,同时还能提供生活热水。准确地说:地源热泵是利用地球表面浅层地热资源作为冷热源,进行能量转换的供暖空调系统。     

农村户用分体式地源热泵系统运行特性分析及应用——以邯郸地区某示范项目为例

为了解决京津冀地区农村冬季采暖存在的环境污染问题,以邯郸地区示范项目典型农宅为例,提出了一种新型的分体式地源热泵系统。首先,利用TRNSYS软件建立分体式地源热泵系统模型,模拟分析了系统的长期运行特性;再通过费用年值法和污染物排放量计算,对比分析该地区常见的4种采暖方式的经济性和环境效益;最后选出最合理的运行系统。结果表明：1）分体式地源热泵系统运行高效且稳定,运行期间系统COP达3.5以上,热泵机组COP达4.0以上;2）在间歇运行方式下,土壤平均温度一年的降幅为0.8%,十年的降幅为3.6%;3）在4种采暖方式综合对比下,分体式地源热泵系统运行费用较低且环保性较好。分体式地源热泵系统的运行性能研究为户用分体式地源热泵系统在京津冀地区典型农宅的应用推广提供了参考借鉴。     

小型污水源热泵系统运行实验研究

介绍了小型污水源热泵系统实验装置在冬季供暖运行和夏季制冷运行实验情况,测试了运行工作时实验系统的COP、污水温度变化情况、室内外温度变化情况和冷凝器和蒸发器进出口温度变化情况以及其他各种参数。实验结果表明,该小型污水源热泵系统具有较高的COP和良好的使用性能,节能效果十分显著。     

小型污水源热泵系统运行实验研究

介绍了小型污水源热泵系统实验装置在冬季供暖运行和夏季制冷运行实验情况,测试了运行工作时实验系统的COP、污水温度变化情况、室内外温度变化情况和冷凝器和蒸发器进出口温度变化情况以及其他各种参数。实验结果表明,该小型污水源热泵系统具有较高的COP和良好的使用性能,节能效果十分显著。     

浅谈土壤源热泵节能措施

目前随着人们对建筑室内环境舒适度的要求的不断提高,各种类型的暖通空调系统得以大范围的推广开来,然而在能源日益紧缺的大时代背景下,迫使暖通空调系统向节能性方向发展,通过技术上的创新来利用可再生能源替代短缺能源,而土壤源热泵系统就是应运而生的可再生能源建筑应用技术之一。然而土壤源热泵由于面世时间较短,系统并没有得到最大化完善,目前影响地埋管束换热效率的因素包括管径、钻孔直径与钻孔间距、管内流体及进出口温度、管材、埋管方式及深度、土壤深度等[1-3]。下面就几个主要影响因素以及有关提高土壤源热泵换热效率作简要介绍。     

小型污水源热泵系统运行实验研究

介绍了小型污水源热泵系统实验装置在冬季供暖运行和夏季制冷运行实验情况,测试了运行工作时实验系统的COP、污水温度变化情况、室内外温度变化情况和冷凝器和蒸发器进出口温度变化情况以及其他各种参数。实验结果表明,该小型污水源热泵系统具有较高的COP和良好的使用性能,节能效果十分显著。     

太阳能-生物质能-谷电蓄热联合供暖系统研究

为了提高多种新能源组合供暖的热效率,考察太阳能-生物质能-谷电蓄热联合供暖系统的供暖效果,利用TRNSYS软件中的TRNbuild模块对实验室进行供暖期内逐时热负荷仿真计算,以动态负荷为基础搭建太阳能与生物质锅炉联合供暖系统的TRNSYS 模型,并对仿真结果进行了实验验证。研究结果表明：7种运行模式及控制策略联合互补,实现了各单元在供暖过程中不同时段的协调控制,保证了联合供暖系统的稳定运行;联合供暖系统供水温度从40 ℃升高至60 ℃,其供热效率降低了11.08%,太阳能保证率降低了23.35%;集热器面积从20 m²增大到40 m²时,太阳能保证率增加25.99%,供热效率降低了2.11%;集热水箱容积从1.5 m³增大到4 m³时,太阳能保证率增加8.67%,供热效率增加了4.31%;系统平均供热效率实验值与模拟值误差为4.29%,平均供热指标实验值与模拟值误差为6.15%;联合供暖系统测试日平均温度为19.76 ℃,能够达到寒冷地区冬季供暖室内温度18~24 ℃的采暖要求。联合供暖系统具有良好的热舒适性,研究结果可为北方地区多源互补供热系统工程优化设计提供依据。     

Comparing FTTH access networks based on P2P and PMP fibre topologies

There is an ongoing discussion in the market which Next Generation Access (NGA) architecture best suits future needs and which investment and cost differences exist. The discussion can be subsumed as P2P vs. GPON, which is somewhat misleading as this article reveals. The discussion is driven by the fact that the high capital cost and the long asset life time of fibre mean that the technology choices made today will dominate the opportunities for telecommunication business of all market players, incumbents, competitors, content providers and business and residential users for many years in the future.The paper analyzes the cost and other differences between Fibre-to-the-Home (FTTH) access network architectures and their related different wholesale approaches by using the well-known and understood steady state approach applied in other NGA analyses in the past. In addition to the steady state analysis a dynamic cost evaluation is included taking into account the different investment behaviour of the FTTH architectures over time. The results describe investment and cost differences between architectures, incumbents and wholesale based competitive operators. The analysis has been performed for different geotypes (clusters) of decreasing population density in a representative European settlement structure.     

面向对象的程序设计

用Ｃ＋ ＋ 语言阐述面向对象程序设计中封装和继承的概念以及在实际中怎样运用这些概念提高程序设计水平。     

Indigenous peoples’ nutrition transition in a right to food perspective

In indigenous communities the nutrition transition characterized by a rapid westernization of diet and lifestyle is associated with rising prevalence of chronic disease. Field work and literature reviews from two different policy environments, Argentina (Jujuy) and Canada (Nunavut), identified factors that add to indigenous peoples’ disease risk. The analytical framework was the emerging human right to adequate food approach to policies and programmes. Indigenous peoples’ chronic disease risk tends to increase as a result of government policies that infringe on indigenous peoples’ livelihoods and territories, undermining their economic system, values and solidarity networks. Policies intended to increase food security, including food aid, may also fuel the nutrition transition. There is a need to explore further the connection between well-intended policies towards indigenous peoples and the development of chronic diseases, and to broaden the understanding of the role that different forms of discrimination play in the westernization of their lifestyles, values and food habits. Food policies that take due account of indigenous peoples’ human rights, including their right to enjoy their culture, may counteract the growth of chronic disease in these communities.     

应用CGI技术创建CAI网页计数器

:CGI( Common Gateway Interface)是应用程序与 Web服务器交互的一个标准接口 ,利用该技术可以实现 HTML不具备的交互式主页功能。本文将通过“教育窗”主页的访问 (点击 )计算器的开发应用实例 ,提出了两种使用 CGI技术实现点击计数的方案     

钻井现场H2S气体的探测及防护

在钻井生产过程中，实施HSE管理体系，预防和控制H2S，保护每一位员工不受H2S气体危害，是钻井生产过程中HSE工作的重要一环。阐述了有害气体H2S的物理特性、毒性标准，介绍了几种常用的H2S气体探测器，以及具体操作方法。     

A strategic skill based model of supplier integration and its effect on supply management performance

Supplier integration is a tool to help organizations gain competitive advantage. Strategic supply management skills and the supply management function's perceived status are hypothesized as antecedents to supplier integration leading to supply management performance. The sample for this study includes 152 executive level supply management professionals. The empirical results suggest that strategic skills and perceived status are essential antecedents to supplier integration and subsequent performance. Further, the relationship between strategic skills and performance is mediated by supplier integration. Results of a dominance analysis also suggest which strategic skills are most likely to explain status integration, and performance. These findings have significant implications for supply management theory and practice.     

Migration to 3G wireless broadband internet and real options: The case of an operator in India

The paper focuses on third generation wireless technologies and on alternative technologies for wireless local area networks. The authors present the evolutionary migration path from second to third generation systems. Technological, economic and behavioral factors related to decision-making towards the migration are proposed. As an example, the paper studies the case of the national incumbent operator of India. It analyzes qualitatively the migration problem from the perspective of the operator, the equipment manufacturer and the users. For the quantitative analysis, real options are used to value the investment decisions. The analysis suggests that the initial (sunk) investment cost, the average revenue per user, the growth of the subscriber base and the volatility of the markets are the key factors in the investment process.     

Collectivism,individualism, and outgroup cooperation in a segmented China

A consistent theme in cross-cultural management research is that collectivists are more cooperative than individualists. We use Hofstede's measure for individualism–collectivism and combine it with an experimental measure of cooperation to test this relationship in China. In contrast to the established paradigm, we find that groups with higher individualistic scores are more cooperative than those groups with higher collectivistic scores. We attribute these results to groups being composed of outgroup members. In addition, we find that subjects from the more developed coastal area are more individualistic and cooperative than are subjects from inland China.

Cost allocation of WCDMA and wholesale pricing for mVoIP and data services

This study estimates cost-based prices for wholesale voice and data services provided to 3G (WCDMA) MVNOs according to their distinct types. For estimation, 3G MVNOs are classified into different types, and the overall cost of WCDMA facilities are separated into voice and data components based on their subscriber rates, actual traffic rates, as well as efficiency consideration of traffic rates. The study then calculates cost-based wholesale prices of voice and data services for each of the 3G MVNO types. The result of this study shows that a cost-plus pricing scheme can help achieve the policy goals of the regulator, namely, lowering telecommunications tariffs and facilitating the introduction of new convergent-type services, far more effectively than the current retail-minus pricing scheme. The findings of this study may assist firms in developing business models based on 3G networks and telecom regulators in designing policies related to interconnection, mVoIP, prepaid calls, wholesale services, and network neutrality.     

压入式局部通风技术及管理

局部通风技术及管理在大中小型煤矿广泛应用,如何管理和应用局部通风是掘进安全生产不可忽视的环节,无论从风量的设计、各种安全设施的使用等都是非常重要的。有一套系列化的设计和管理模式是掘进安全生产的重要保证,本文从掘进设计到掘进结束做了详细的使用和管理。