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81.
结合总体节能目标,对秦皇岛市“十二五”期间的能源需求进行了预测,并对三大产业能源利用形式及能源利用比例进行了分析。结果表明,第二产业的能源消耗比重最大,将成为节能总量控制的重点,而重中之重则是其中的工业领域节能。测算并分析了工业领域的节能潜力,范围涵盖玻璃制造、装备制造、粮油食品制造、金属压延业、建材、电力、化工7个主要行业。  相似文献   
82.
We use a travel cost model to test the effects of wild and prescribed fire on visitation by hikers and mountain bikers in New Mexico. Our results indicate that net benefits for mountain bikers is $150 per trip and that they take an average of 6.2 trips per year. Hikers take 2.8 trips per year with individual net benefits per trip of $130. Both hikers' and mountain bikers' demand functions react adversely to prescribed burning. Net benefits for both groups fall as areas recover from prescribed burns. Because both visitation and annual recreation benefits decrease to these two types of visitors, this gives rise to multiple use costs associated with prescribed burning. With respect to wildfire, hikers and mountain bikers both exhibit decreased visitation as areas recover from wildfires, however, only hikers indicate an increase in per trip net benefits. Bikers' demand effectively drops to zero. These results differ from previous findings in the literature and have implications for efficient implementation of the National Fire Plan and whether prescribed burning is a cost effective tool for multiple use management of National Forests. Specifically, that fire and recreation managers cannot expect recreation users to react similarly to fire across recreation activities, or different geographic regions. What is cost effective in one region may not be so in another.  相似文献   
83.
    
ABSTRACT: This study examines water consumption characteristics in Casablanca and analyzes approaches for sustainable water demand management. Research procedures involve the development and estimation of water demand models for the residential/commercial, industrial, and institutional sectors; forecasts of water demand to 2010; and simulation of the effects of a complex of water conservation methods on the forecasted demands. The results indicate that residential/commercial water demand is weakly responsive to price changes (elasticity =?0.448) while institutional water demand is slightly more responsive (elasticity =?0.648). The conservation approaches used in the simulations included public education, plumbing code revisions to require use of water conservation devices, leak detection and repair, pricing policy, metering, and pressure reduction. The results indicate that considerable saving in water use can be attained through a comprehensive water demand management program.  相似文献   
84.
Sustainable use of water and land resources requires that these scarce resources be appropriately allocated among various competing human activities. Worldwide, there is a realization now that sustainable river basin management should be accorded the highest priority, because it deals not only with technical, but also with ecological and socioeconomic aspects, and thus calls for a multidisciplinary and integrated approach. However, most of the policy and planning documents have either remained silent, or have made only implicit reference to the importance of environmental water demand (EWD) and its quantification. Therefore, in the light of its importance, a methodology has been evolved in this article for quantifying EWD for various forested areas in two distinctly different Indian river basins: Brahmani (humid zone) and Sabarmati (dry zone). The article analyzes and discusses EWD estimates at three different spatial levels: river basins, states, and districts within them, and finally presents a comparative analysis of all these results. Findings of the present study will be immensely useful in understanding various ecological issues connected with water resource projects and proposals in these river basins.  相似文献   
85.
    
Using meteorological and electricity demand data for a 4-year period, electricity demand in Shetland was modeled to provide an estimate of the demand over a 30-year period from 1 January 1981. That modeled demand was then compared to estimated wind power output over the same period using the WAsP model. The wind farm output was estimated for a range of sizes of wind farm up to the consented 370 MW Viking Wind Farm in Shetland. Some wind power was available for 94% of the time and the 370 MW wind farm would meet 100% of demand for nearly 80% of the time. The statistics of single and accumulated deficits were calculated for a range of wind farms and estimates of the amount of additional generation capacity and additional power requirements were assessed. The study suggests that with storage, wind power in Shetland could meet all electricity demand in Shetland at around £130 to £150/MWh (excluding subsidy) and with a grid connection allowing the sale of excess power, those costs could be reduced.  相似文献   
86.
    
ABSTRACT

This paper proposes a novel congestion management (CM) approach by using the optimal transmission switching (OTS) and demand response (DR) for a system with conventional thermal generators and renewable energy sources (RESs). In this paper, wind and solar PV units are considered as the RESs. The stochastic behavior of wind and solar PV powers are modeled by using the appropriate probability density functions (PDFs). The proposed CM methodology simultaneously optimizes the generation dispatch, demand response, and also the network topology of the power system. The OTS identifies the branches that should be taken out of service by significantly reducing the operating cost of the system while respecting the system security. Here, the total operating cost minimization/social welfare maximization and system losses minimization are considered as the objectives to be optimized. The proposed CM problem is solved using the multi-objective Jaya algorithm and it is used to determine a set of Pareto-optimal solutions. The Jaya algorithm is simple and it does not have any algorithmic-specific parameters to be tuned. This aspect reduces the designer’s effort in tuning the parameters to arrive at the optimum objective function value. A fuzzy logic-based approach is used to identify the best compromise solution. The effectiveness of the proposed CM approach is examined on modified IEEE 30 and practical Indian 75 bus test systems. The obtained simulation results are analyzed and they show the effectiveness of the proposed approach.  相似文献   
87.
用分光光度法测定水中化学需氧量CODCr,通过正交试验选择氧化的最佳选择。试验结果表明对CODCr值为50~1000mg/L的水样:氧化剂K2Cr2O7用量为0.20~0.40mol/L,催化剂Ag2SO4用量为10g/LH2SO4,消解时间10min,加热温度180℃。用CODCr为138mg/L的质控标样进行验证试验,其绝对误差为0.5~3.0mg/L。与标准方法相比用分光光度法测定CODCr具有分析误差小,省时、省力,节约药剂的特点。  相似文献   
88.
针对供热系统存在的水力失衡、能耗高、故障多、事故风险大等问题,分析了系统中的主要能耗环节和危险性,提出了安全节能自控系统的结构,详细研究和分析了主系统和子系统的工作原理及节能机制,设计开发了集实时智能自动监控、预警报警、故障诊断、数据管理、安全分析等功能于一体的安全节能自控系统。所开发系统的工程示范应用表明达到了一定程度的节能降耗、安全稳定和经济运行的良好效果。  相似文献   
89.
风能资源开发利用的社会需要和发展前景   总被引:7,自引:0,他引:7  
开发风能资源、利能风力发电在我国虽然只有数十年,但发展却很快。作为可再生的清洁能源越来越受到重视。不仅有巨大的环保意义,也有突出的经济效益。本文从风能利用的意义和社会需要展开论证,结合我国风能资源利用的概况,特别是结合风电装机最多的新疆的实际情况进行估算,从多侧面论述了风能资源的开发利用问题。  相似文献   
90.
Abstract: Sediment oxygen demand (SOD) is believed to be an important process affecting dissolved oxygen (DO) concentrations in blackwater streams of the southeastern coastal plain. Because very few data on SOD are available, it is common for modelers to take SOD values from the literature for use with DO models. In this study, SOD was measured in seven blackwater streams of the Suwannee River Basin within the Georgia coastal plain for between August 2004 and April 2005. SOD was measured using four in situ chambers and was found to vary on average between 0.1 and 2.3 g O2/m/day across the seven study sites throughout the study period. SOD was found to vary significantly between the watersheds within the Suwannee River Basin. However, land use was not found to be the driving force behind SOD values. Statistical analyses did find significant interaction between land use and watersheds suggesting that an intrinsically different factor in each of the watersheds may be affecting SOD and the low DO concentrations. Further research is needed to identify the factors driving SOD dynamics in the blackwater streams of Georgia’s coastal plain. Results from this study will be used by the Georgia Department of Natural Resources – Environmental Protection Division as model input data for the development and evaluation of DO total maximum daily loads in the Georgia coastal plain.  相似文献   
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