浅谈燃气计量设备的施工及运行管理

本文介绍了影响燃气计量设备计量准确的因素,并从施工、设计及运行管理等环节加强控制,提高计量设备的计量精度,减少产供销差率,保证企业的收入。     

新宁电子保税仓储VMI服务分析

江苏新宁现代物流股份有限公司是较早进入国内电子元器件保税仓储行业的企业,拥有自主开发的仓储管理系统,并依托该系统在业内率先摸索并形成具有自身特色的VMI、DC业务模式。相关仓储物流行业对盈利模式的成功复制及国内电子信息产业的发展为公司带来良好的发展空间。文章对新宁物流电子保税仓储VMI服务进行分析,为业内其他物流公司实施保税仓储VMI服务提供借鉴。     

Biofuel policies and the environment: Do climate benefits warrant increased production from biofuel feedstocks?

We examine whether climate benefits warrant policies promoting biofuel production from agricultural crops when other environmental impacts are accounted for. We develop a general economic-ecological modelling framework for integrated analysis of biofuel policies. An economic model of farmers' decision making is combined with a biophysical model predicting the effects of farming practices on crop yields and relevant environmental impacts. They include GHG emissions over the life cycle, nitrogen and phosphorus runoff, and the quality of wildlife habitats. We apply our model to crop production in Finland. We find that under current biofuel production technology the case for promotion of biofuels is not as evident as has been generally thought. Only reed canary grass for biodiesel is unambiguously desirable, whereas biodiesel from rape seed and ethanol production from wheat and barley cause in most cases negative net impacts on the environment. Suggested policies in the US and the EU tend to improve slightly the environmental performance of biofuel production.     

The economic impact of shale gas extraction: A review of existing studies

Recent advances in drilling technology have allowed for the profitable extraction of natural gas from deep underground shale rock formations. Several reports sponsored by the gas industry have estimated the economic effects of the shale gas extraction on incomes, employment, and tax revenues. None of these reports has been published in an economics journal and therefore have not been subjected to the peer review process. Yet these reports may be influential to the formation of public policy. This commentary provides written reviews of several studies purporting to estimate the economic impact of gas extraction from shale beds. Due to questionable assumptions, the economic impacts estimated in these reports are very likely overstated.     

250吨转炉静电除尘器稳定运行探讨

静电除尘器是一种高效的除尘器,已被越来越多的炼钢厂转炉所采用.为了保持静电除尘器长期、高效、稳定地运行,应该对影响静电除尘器除尘效率的因素进行分析,并加强对静电除尘器运行、维护和检修的管理.     

桑弘羊理财思想的当代意义

西汉时期桑弘羊参与并主持了诸如盐铁酒专营、均输、平准和统一铸币权等重大财经政策的制订和实施,这些改革政策起到了既增加中央政府财力又加强了中央集权统治的作用。如今借鉴桑弘羊的财政政策和理财思想,得出以下启示：政府增加国家财政收入的目的是为了减轻百姓负担,提高人民生活水平,关系国计民生的重要物质资料必须由国家掌握,财政政策、货币政策与市场机制相互协调,要正确把握农工商业三者对立统一的辩证关系,要充分培育并扩展市场,特别是要培育农村市场和拓展国际市场以服务于社会主义市场经济。     

基于“北斗一代”的Zigbee无线网关设计

为了解决野外多点数据采集无供电、布线复杂和通信困难的问题,提出了一种基于“北 斗一代”的Zigbee无线网关设计方案。采用MSP430F6438、CC2341微处理器和一体化的RDSS “北斗”射频芯片完成低功耗、小成本的硬件设计。通过增加SIM卡的数量,将网关转发“ 北斗”数据的频率降至最低的5 s,提高了网关的通信速率。通过软件设计实现了Zigbee无 线传感网络和“北斗一代”系统之间数据的透明交换。该方法已成功应用于野外油气井远程 监控系统中。     

Incomplete Credit Markets and Commodity Marketing Behaviour

We use a simple theoretical model of seasonal market participation in the presence of liquidity constraints and transaction costs to explain the ‘sell low, buy high’ puzzle in which some households do not take advantage of inter‐temporal price arbitrage through storage and sell output postharvest at prices lower than observed prices for purchases in the subsequent lean season. We test our model with data from western Kenya using maximum likelihood estimation of a multivariate sample selection model of market participation. Access to off‐farm income and credit indeed seem to influence crop sales and purchase behaviours in a manner consistent with the hypothesised patterns.     

烟气脱硫脱硝一体化技术的现状与展望

介绍了烟气脱硫脱硝的机理和技术现状,在对炭基材料法、臭氧氧化法、电子束法等烟气脱硫脱硝技术分析的基础上,指出烟气脱硫脱硝一体化技术具有较好的经济、环境和社会效益,是一种适合我国的烟气净化技术,但仍需要进一步的研究和开发。     

The adaptive approach for storage assignment by mining data of warehouse management system for distribution centres

Among distribution centre operations, order picking has been reported to be the most labour-intensive activity. Sophisticated storage assignment policies adopted to reduce the travel distance of order picking have been explored in the literature. Unfortunately, previous research has been devoted to locating entire products from scratch. Instead, this study intends to propose an adaptive approach, a Data Mining-based Storage Assignment approach (DMSA), to find the optimal storage assignment for newly delivered products that need to be put away when there is vacant shelf space in a distribution centre. In the DMSA, a new association index (AIX) is developed to evaluate the fitness between the put away products and the unassigned storage locations by applying association rule mining. With AIX, the storage location assignment problem (SLAP) can be formulated and solved as a binary integer programming. To evaluate the performance of DMSA, a real-world order database of a distribution centre is obtained and used to compare the results from DMSA with a random assignment approach. It turns out that DMSA outperforms random assignment as the number of put away products and the proportion of put away products with high turnover rates increase.