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71.
本文结合士兵系统的发展概况,阐述了单兵装备人机工程仿真评价技术研究的重要性,并总结了目前的研究进展情况,进而重点介绍单兵装备人机工效仿真评价系统的最新研究成果,首次在三维仿真环境和基础数据库的支持下对单兵装备系统的可视性、可达性、舒适性等指标进行综合研究和评价。  相似文献   
72.
The drying up of the fossil energy sources and the damage from unchecked carbon emissions demand the development of low carbon economy, which promotes the development of new energy sources, such as wind power and photovoltaic. However, the direct connections of wind/photovoltaic power into power grid bring great impacts on power systems, thus affecting the security and stability of power system operations, which challenges the power system dispatching. In despite of many methods for power system dispatch, lack of the models, for power system containing wind power and photovoltaic considering carbon trading and spare capacity variation (PSCWPCCTSCV), restricts the further optimal operations of power systems. This paper studies the economic dispatch modeling problem of power system containing wind power and photovoltaic, establishes the model of economic dispatch of PSCWPCCTSCV. On this basis, adaptive immune genetic algorithm is applied to conduct the economic operation optimization, which can provide the optimal carbon trading price and the optimal power distribution coefficient. Finally, simulations based on the newly proposed models are made to illustrate the economic dispatch of PSCWPCCTSCV. The results show that optimization with the proposed model can not only weaken the volatility of the new energy effectively, but also reduce carbon emissions and reduce power generation costs.  相似文献   
73.
The octanol–air partition coefficients (KOA) for PBB15, PBB26, PBB31, PBB49, PBB103 and PBB153 were determined as a function of temperature using a gas chromatographic retention time technique with 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (p,p′-DDT) as a reference substance. The internal energies of phase change from octanol to air (ΔOAU) were calculated for the six compounds and were in the range from 74 to 116 kJ mol−1. Simple regression equations of log KOA versus relative retention times (RRTs) on gas chromatography (GC), and log KOA versus molecular connectivity indexes (MCI) were obtained, for which the correlation coefficients (r2) were greater than 0.985 at 283.15 K and 298.15 K. Thus the KOA values of the remaining PBBs can be predicted by using their RRTs and MCI according to these relationships.  相似文献   
74.
Based on shift-share method, this article employs re- gional share, structural shift and competitive shift to analyze the structural benefit and competitive position of agricultural structure in western China by comparing with agriculture, foresting, stockbreeding and fishing before and after Conversion of Farmland to Forest and Grassland (CFFG). Then authors draw following conclusion: while CFFG program has been put in practice, the agricultural structure in western China has some typical characteristics, such as growth faster, structural predominance obvious and more competitive. But the contributiveness from the competition is not too much yet, and the structural benefit of forest estate and stockbreeding are restrained.  相似文献   
75.
生物反应器填埋的沉降加速效应   总被引:1,自引:0,他引:1  
通过实验室填埋柱模拟实验,研究了生物反应器填埋操作方式对填埋层沉降的影响。结果表明:与传统卫生填埋方式相比,回灌经厌氧生物处理后渗滤液的生物反应器填埋方式能够加速填埋层的沉降,140 d内沉降提高比例达10%以上。我国填埋垃圾高含水率、高易腐有机物含量的特性,使得其填埋层的次沉降系数高于文献值。填埋垃圾有机物降解量及其引起的垃圾水分排出量与填埋层沉降有显著相关性,表明有机物降解是引起填埋层沉降的重要因素,也是造成生物反应器填埋与传统卫生填埋方式初期沉降差异的主要原因。  相似文献   
76.
废弃印刷线路板碘化法浸金研究   总被引:1,自引:0,他引:1  
针对碘化法从废弃印刷线路板中提取金的工艺设计,分别考察了碘的质量分数、n(I2)/n(I-)比值、固液比、双氧水的质量分数、pH值、浸出时间和浸出温度对金浸出率的影响。结合正交设计优化实验方法,提出了从废弃印刷线路板中碘化法浸取金的最佳工艺条件:碘的质量分数为1.1%,n(I2)∶n(I-)=1∶10,双氧水的质量分数为1.5%,浸出时间4 h,固液比为1∶10,浸出温度为常温(25℃),溶液pH值为中性,此时金浸出率可达97.5%。  相似文献   
77.
采用新型膜蒸馏技术对水中As(III)与As(Ⅴ)的去除展开了研究。实验结果表明,膜蒸馏对水中As (III)及As (Ⅴ)具有较高的去除能力:当产水中砷含量超过10 μg/L时,原水中As (III)与As (Ⅴ)的浓度可分别高达40 mg/L和2 000 mg/L。局部润湿现象的存在导致As (III)及As (Ⅴ)跨膜至产水侧,PVDF微孔膜在溶液中的负电性以及As (III)与 As (Ⅴ)在溶液中存在形式的不同导致膜蒸馏对两者去除能力的差异。360 h连续运行过程中产水通量及电导率稳定,且整个过程中As (III)均低于检测限,说明PVDF微孔膜具有良好的疏水性和稳定的除砷性能。  相似文献   
78.
Odorous air samples collected from several sources were presented to an olfactometer, an electronic nose, a hydrogen sulfide (H(2)S) detector and an ammonia (NH(3)) detector. The olfactometry measurements were used as the expected values while measurements from the other instrumentation values became input variables. Five hypotheses were established to relate the input variables and the expected values. Both linear regression and artificial neural network analyses were used to test the hypotheses. Principal component analysis was utilized to reduce the dimensionality of the electronic nose measurements from 33 to 3 without significant loss of information. The electronic nose or the H(2)S detector can individually predict odor concentration measurements with similar accuracy (R (2) = 0.46 and 0.50, respectively). Although the NH(3) detector alone has a very poor relationship with odor concentration measurements, combining the H(2)S and NH(3) detectors can predict odor concentrations more accurately (R (2) = 0.58) than either individual instrument. Data from the integration of the electronic nose, H(2)S, and NH(3) detectors produce the best prediction of odor concentrations (R (2) = 0.75). With this accuracy, odor concentration measurements can be confidently represented by integrating an electronic nose, and H(2)S and NH(3) detectors.  相似文献   
79.
A novel biomimetic absorbent containing the lipid triolein was developed for removing persistent organic pollutants (POPs) from water. The structural characteristics of the absorbent were obtained by SEM and a photoluminescence method. Under optimum preparation conditions, triolein was perfectly embedded in the cellulose acetate (CA) spheres, the absorbent was stable and no triolein leaked into the water. Dieldrin, endrin, aldrin and heptachlor epoxide were effectively removed by the CA--triolein absorbent in laboratory batch experiments. This suggests that CA-triolein absorbent may serve as a good absorbent for those selected POPs. Triolein in the absorbent significantly increased the absorption capacity, and lower residual concentrations of POPs were achieved when compared to the use of cellulose acetate absorbent. The absorption rate for lipophilic pollutants was very fast and exhibited some relationship with the octanol--water partition coefficient of the analyte. The absorption mechanism is discussed in detail.  相似文献   
80.
浅谈外墙保温材料对建筑防火的影响   总被引:1,自引:0,他引:1  
曲毅  仝艳时 《安全》2008,29(11):6-8
本文通过对几种外墙保温材料及国内外外墙保温技术的介绍,从中分析出引起建筑耐火极限降低的原因,找到在目前条件下,最适合外墙保温的材料及技术,以降低火灾的发生。  相似文献   
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