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1.
K-栅栏覆盖是无线传感器网络覆盖控制的研究热点之一。本文构建了强栅栏覆盖模型,提出了分区强K-栅栏覆盖构建算法PMNSB,用最少的节点形成强栅栏。首先把监控区域分成多个子区域,通过匈牙利算法选用移动距离之和最少的网格集合为基准1-栅栏覆盖,缺少移动节点的子区域,选择附近区域的剩余移动节点修补形成1-栅栏覆盖。水平相邻的两个子区域之间构建竖直栅栏,这些1-栅栏合起来构成强K-栅栏覆盖。仿真结果证明了该方法的有效性,本文的研究对提升无线传感器网络的性能具有重要的理论与实际意义。  相似文献   
2.
This research investigates the moderating roles of firm ownership in managerial perceptions of information systems (IS) in transition economies. Analysis of representative survey data from 304 companies in Hungary showed that perceptions of IS are driven by organizational variables in foreign firms, and by environmental variables in domestic firms. The findings embrace a more fine-grained notion of variables affecting IS usefulness in the transition economy context by showing that those are contingent on firm ownership.  相似文献   
3.
中继系统下的众多资源分配策略很少同时考虑多用户情形下的子载波配对和不同用户需求。针对这一问题,提出了一种基于QoS(服务质量)保证和比例公平的多用户子载波配对和功率分配算法,该算法既能保证QoS用户的最小速率要求,又能满足BE(尽力而为)用户之间速率比例公平的准则。该算法首先根据不同用户需求分配第二跳的子载波,然后利用匈牙利配对算法得到两跳子载波的最佳配对,最后用类似注水算法进行功率分配。仿真结果表明,所提算法在满足用户QoS保证和比例公平准则的同时有效提升了系统的吞吐量。  相似文献   
4.
变批量生产是一种先进制造模式,根据生产批量,合理调配制造资源,是实现该模式的可行途径。根据建立的制造资源分级数据库,结合目标期望,得到资源的能力和使用成本,将设备与工序之间的配置转化为分配问题,运用“匈牙利算法”得到选配结果,重复使用该法,可以获得多条工艺路线。最后以算例说明方法的可行性。  相似文献   
5.
Thermal wells have been used in Hungary for over 140 years. As thermal water production has increased during the past decades, the pressure drawdown has increased in the geothermal systems of the Pannonian basin, showing that their sustainable management is lacking. The Hódmez?vásárhely, Szeged, and Szentes case histories are presented, including the very first indications of stabilization and recharge of the Pannonian thermal aquifers, as a result of reduction of thermal water production. Sustainable production and overall resource management of geothermal systems in SE-Hungary can only be achieved by injection.  相似文献   
6.
The hydrogen economy is seeking its killer application, which can break down the ‘chicken and egg problem’, i.e., no hydrogen powered car can be sold if it cannot be refueled, and nobody will invest to a hydrogen refueling station if no one has a hydrogen powered vehicle. The applications like material handling, backup-power, and small stationary combined heat and power (CHP) engines are the most promising candidates, which may show financial return in 3–5 years. The replacement of fossil fuel with hydrogen in the automotive industry offers a substantial reduction of the harmful environmental effects, however, it is still the most challenging because of the absence of the hydrogen infrastructure, the price and the lifetime of the fuel cell (FC) engine and the unsuitable regulations, as well. In this work a new possible market was identified and analyzed in different points of view. This market segment is a car-sharing system operating with small urban vehicles, which not only can solve some environmental problems (e.g., air pollution and CO2 emission), but also helps to reduce congestion, secure energy supply and ease its distribution. First, a sensitivity analysis was done and the key performance indicators of the system were determined. The financial return of a hydrogen-based car-sharing system was examined carefully as a function of the rated power of the fuel cell power train, the way of hydrogen supply, the cost of the hydrogen and the size of the car fleet. Finally, a possible hydrogen-based car-sharing service was designed and optimized to the downtown of Budapest, Hungary. A sustainable system was proposed, which can satisfy the needs of the business (i.e., profitability) and the environment.  相似文献   
7.
根据某监理公司的具体情况,在人员组织安排上,运用现代管理科学的方法,合理安排、充分利用,达到工程项目所要求的监理人员素质,保证工程能够顺利进行。  相似文献   
8.
Hierarchical Bayesian modelling is considered for the number of age-dependent deaths in different geographic regions. The model uses a conditional binomial distribution for the number of age-dependent deaths, a new family of zero mean Gaussian Markov random field models for incorporating spatial correlations between neighbouring regions, and an intrinsic Gaussian model for including correlations between age-dependent mortality rates. Age-dependent mortality rates are estimated for each region, and approximate credibility intervals based on summaries of samples from the posterior distribution are obtained from Markov chain Monte Carlo simulation. The consequent maps of mortality rates are less variable and smoother than those which would be obtained from naive estimates, and various inferences may be drawn from the results. The prior spatial model includes some of the common conditional autoregressive spatial models used in epidemiology, and so model uncertainty in this family can be accounted for. The methodology is illustrated with an actuarial data set of age-dependent deaths in 150 geographic regions of Hungary. Sensitivity to the prior distributions is discussed, as well as relative risks for certain covariates (males in towns, females in towns, males in villages, females in villages).  相似文献   
9.
This paper describes the status of geothermal energy utilization—direct use—in Hungary, with emphasis on developments between 2000 and 2002. The level of utilization of geothermal energy in the world increased in this period and geothermal energy was the leading producer, with 70% of the total electricity production, of all the renewable energy sources (wind, solar, geothermal and tidal), followed by wind energy at 28%. The current cost of direct heat use from biomass is 1–5 US¢/kWh, geothermal 0.5–5 US¢/kWh and solar heating 3–20 US¢/kWh. The data relative to direct use in Hungary decreased in this period and the contribution of geothermal energy to the energy balance of Hungary, despite significant proven reserves (with reinjection) of 380 million m3/year, with a heat content of 63.5 PJ/a at ΔT=40 °C, remained very low (0.25%). Despite the fact that geothermal fluids with temperatures at the surface higher than 100 °C are available, no electricity has been generated. As of 31 December 2002, the geothermal capacity utilised in direct applications in Hungary is estimated to be 324.5 MWt and to produce 2804 TJ/year. Geothermal heat pumps represent about 4.0 MWt of this installed capacity. The quantity of thermal water produced for direct uses in 2002 was approximately 22 million m3, with an average utilization temperature of 31 °C. The main consumer of geothermal energy is agriculture (68% of the total geothermal heat dedicated to direct uses). The geothermal water is used only in five spas for space heating and sanitary hot water (SHW), although there are 260 spas in the country, and the thermal water produced has an average surface temperature of 68 °C. The total heat capacity installed in the spas is approximately 1250 MWt; this is not provided by geothermal but could be, i.e., geothermal could provide more than three times the geothermal capacity utilized in direct uses by 31 December 2002 (324.5 MWt).  相似文献   
10.
This work is focussing to the thermo-catalytic batch pyrolysis of contaminated real municipal plastic waste using different catalyst mixtures in their different ratios: Ni/ZSM-5, red mud, Ca(OH)2 and Ni/SAPO-11, red mud, Ca(OH)2. The effect of the catalysts to the pyrolysis oil properties and the in-situ upgrading (especially the storage, transportation and corrosion stability) of pyrolysis oil was investigated. High concentration of Ni/ZSM-5 and Ni/SAPO-11 zeolites in catalyst mixtures can increase the yield of gases and pyrolysis oil, the concentration of aromatics or the hydrogen content in gases; however the presence of red mud in higher content can further increase the hydrogen concentration. ZSM-5 based catalysts showed higher efficiency in aromatization reactions. An accelerated aging test at 80 °C till 1 week was performed to investigate the storage and transportation stability of pyrolysis oils. Only slight increase was found in the density and viscosity, on the other hand there was a bit greater increase using SAPO-11 based catalysts than ZSM-5. The change in the olefin content was followed via bromine number and FTIR spectra of pyrolysis oil, which resulted ~3% and ~4% decreasing using Ni/ZSM-5 and Ni/SAPO-11 containing catalyst mixtures. Regarding acidic components, they significantly increased by aging time, while the high red mud and/or Ca(OH)2 in catalyst mixtures had notable benefit, because they can drastically decrease the concentration of chlorinated compounds, which led to less weight loss during corrosion test using copper plate till 60 days at 20 °C.  相似文献   
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