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5万吨储量水泥熟料库结构选型对比分析 被引量:2
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作者 蒋守锋 《四川水泥》 2017年第11期1-1,共1页
水泥工业设计中,5w吨储量水泥熟料十分常见,何种高径比是最经济合理的选择,相关规范及文献中均未提及,本文结合当下水泥工业中常用的三种高径比选型进行经济性比较,希望能够为方案设计人员提供一个参考。
关键词 库径 造价 储量
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大规模复杂路网条件下的快速径路搜索算法研究 被引量:2
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作者 范家铭 李博 贺俊源 《铁道运输与经济》 北大核心 2022年第8期123-129,共7页
我国铁路建设规模日益扩大,路网连接关系错综复杂,在满足铁路运营条件基础上,快速制定出合理、有效的列车行车径路方案变得更加困难。传统径路搜索方法如深度优先算法、广度优先算法和A*搜索算法等已不能满足大规模复杂路网条件下径路... 我国铁路建设规模日益扩大,路网连接关系错综复杂,在满足铁路运营条件基础上,快速制定出合理、有效的列车行车径路方案变得更加困难。传统径路搜索方法如深度优先算法、广度优先算法和A*搜索算法等已不能满足大规模复杂路网条件下径路的快速搜索。为了解决大规模复杂路网条件下最优径路的快速搜索问题,对比分析传统的径路搜索方法优缺点,选择基于双向搜索算法的基础上,引入限定车站属性搜索、优化车站节点搜索、向量限定搜索、限定节点分支递归深度、建立现行列车径路库等优化策略来提升搜索算法的执行效率,双向搜索优化算法能够快速规划列车径路方案,保证算法的良好性能,为开行方案、运行图计划提供理论支撑,对优化运力资源配置、提升路网管理水平具有重要意义。 展开更多
关键词 行车 搜索算法 优化 递归
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ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR 被引量:1
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作者 DAIChang-lei CHIBao-ming GAOShu-qin 《Chinese Geographical Science》 SCIE CSCD 2005年第1期60-63,共4页
Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir... Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and compositions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the paper analyzed quantity available and regulation coefficient of different regulated water and established a formula to calculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River, Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible. With some constraint conditions, the formula can be adopted in other similar areas. 展开更多
关键词 groundwater reservoir regulated water resources resources analysis composition analysis water quantity calculation
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Experimental Analysis of Sediment Deposition Due to the Effect of an Upstream Reservoir Backwater
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作者 Issa E. Issa Nadhir Al-Ansari +1 位作者 Moayad Khaleel Sven Knutsson 《Journal of Civil Engineering and Architecture》 2014年第9期1185-1193,共9页
The phenomenon of aggradation due to sediment accumulation upstream reservoirs had been studied in this research. For this purpose, groups of experiments were conducted in a laboratory with 25 m long, 0.80 m wide and ... The phenomenon of aggradation due to sediment accumulation upstream reservoirs had been studied in this research. For this purpose, groups of experiments were conducted in a laboratory with 25 m long, 0.80 m wide and 0.70 m deep channel. A block was built at the end of the channel to work as a dam to impound water. The channel was supplied with drainage pipes on both sides to release water out in a manner similar to what happens in reservoirs. The bed of the channel was filled with sand of 0.80 mm median sieve diameter and 0.72 geometric standard deviation. The slope was 0.0093 for all experiments. Two sizes of sand were used representing the sediment. The median diameter and geometric standard deviation of the first were 0.365 mm and 0.46 mm, respectively. The second sample had 0.65 mm median diameter and 0.67 standard deviation. A total of 70 experiments were conducted in two groups to examine effects of sediment transport rate, particle size of sediment and flow velocity on aggradation characteristics. The results showed that there was a strong linear direct relationship between aggradation elements (length and depth) with the rate of sediment transport. Groups of dimensionless parameters affecting the aggradation characteristics were used to develop empirical equations to predict the length, maximum depth of aggradation and predict transient bed profile. The results of empirical approach were compared with the measurement data and previous numerical method. The results indicated that the percentage error was 19% to 31% for length of aggradation and -21% to 26% for maximum depth of aggradation. The results also showed that the sediment materials were deposited closer to the body of the dam when the released water from the dam is higher than the inflow. 展开更多
关键词 AGGRADATION alluvial channel reservoir sedimentation sediment deposition.
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Runoff and Sediment Load from the Right Bank Valleys of Mosul Dam Reservoir 被引量:1
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作者 Mohammad Ezz-Aldeen Mohammad Nadhir A1-Ansari Sven Knutsson 《Journal of Civil Engineering and Architecture》 2012年第10期1405-1410,共6页
Mosul Dam is a Multipurpose Project on the River Tigris in Iraq with 11.11 billion m3 storage capacity. It is used to store the water for irrigation, hydropower generation, and flood control. As in other dams in the w... Mosul Dam is a Multipurpose Project on the River Tigris in Iraq with 11.11 billion m3 storage capacity. It is used to store the water for irrigation, hydropower generation, and flood control. As in other dams in the world, this dam also have sedimentation problem. Sediment accumulation in its reservoir can effect the dam operation (pumping station, hydropower plants, and bottom outlets) and it will definitely shorten the life span of the dam. In this study, the SWAT (soil and water assessment tool) under (]IS (Geographical Information System) was applied to simulate the yearly surface rtmoff and sediment load for the main three valleys on the right bank of Mosul Dam Reservoir. The simulation considered for the twenty one years begin from the dam operation in 1988 to 2008. The resultant values of the average annual sediment load are 35.6~ 103, 4.9 ~ 103, and 2.2~ 103 ton, while the average values of sediment concentration are 1.73, 1.65, and 2.73 kg/m3 for the considered valleys one, two and three respectively. This implies that significant sediment load enters the reservoir from these valleys. To minimize the sediment load entering the reservoir, a check dam is to be constructed in suitable sites especially for valley one. The check dam can store the runoff water and trap the sediment load, and then the flow can be released to the reservoir. 展开更多
关键词 Mosul dam RUNOFF sediment load SWAT model GIS
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Mechanism and Forecasting Methods for Severe Droughts and Floods in Songhua River Basin in China 被引量:5
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作者 LI Hongyan WANG Yuxin LI Xiubin 《Chinese Geographical Science》 SCIE CSCD 2011年第5期531-542,共12页
The influence of various factors, mechanisms, and principles affecting runoff are summarized as periodic law, random law, and basin-wide law. Periodic law is restricted by astronomical factors, random law is restricte... The influence of various factors, mechanisms, and principles affecting runoff are summarized as periodic law, random law, and basin-wide law. Periodic law is restricted by astronomical factors, random law is restricted by atmospheric circulation, and basin-wide law is restricted by underlying surface. The commensurability method was used to identify the almost period law, the wave method was applied to deducing the random law, and the precursor method was applied in order to forecast runoff magnitude for the current year. These three methods can be used to assess each other and to forecast runoff. The system can also be applied to forecasting wet years, normal years and dry years for a particular year as well as forecasting years when floods with similar characteristics of previous floods, can be expected. Based on hydrological climate data of Baishan (1933-2009) and Nierji (1886-2009) in the Songhua River Basin, the forecasting results for 2010 show that it was a wet year in the Baishan Reservoir, similar to the year of 1995; it was a secondary dry year in the Nierji Reservoir, similar to the year of 1980. The actual water inflow into the Baishan Reservoir was 1.178 × 10 10 m 3 in 2010, which was markedly higher than average inflows, ranking as the second highest in history since records began. The actual water inflow at the Nierji station in 2010 was 9.96 × 10 9 m 3 , which was lower than the average over a period of many years. These results indicate a preliminary conclusion that the methods proposed in this paper have been proved to be reasonable and reliable, which will encourage the application of the chief reporter release system for each basin. This system was also used to forecast inflows for 2011, indicating a secondary wet year for the Baishan Reservoir in 2011, similar to that experienced in 1991. A secondary wet year was also forecast for the Nierji station in 2011, similar to that experienced during 1983. According to the nature of influencing factors, mechanisms and forecasting methods and the service objects, mid-to long-term hydrological forecasting can be divided into two classes:mid-to long-term runoff forecasting, and severe floods and droughts forecasting. The former can be applied to quantitative forecasting of runoff, which has important applications for water release schedules. The latter, i.e., qualitative disaster forecasting, is important for flood control and drought relief. Practical methods for forecasting severe droughts and floods are discussed in this paper. 展开更多
关键词 Songhua River Basin RUNOFF drought and flood forecasting
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Solution of Klein-Gordon Equation for Pseudo-Coulomb Potential Plus a New Ring-Shaped Potential
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作者 肖勇军 隆正文 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期54-56,共3页
Under the condition of an equal mixing of vector and scalar potentials, exact solutions of bound states of theKlein-Gordon equation with pseudo-Coulomb potential plus a new ring-shaped potential are presented. Simulta... Under the condition of an equal mixing of vector and scalar potentials, exact solutions of bound states of theKlein-Gordon equation with pseudo-Coulomb potential plus a new ring-shaped potential are presented. Simultaneously,energy spectrum equations are also obtained. It is shown that the radial equation and angular wave functions areexpressed by confluent hypergeogetric and hypergeogetric functions respectively. 展开更多
关键词 Pseudo-Coulomb potential plus a new ring-shaped potential bound states exact solution
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Molecular Dynamics Simulation on Scale Inhibition Mechanism of Polyepoxysuccinic Acid to Calcium Sulphate 被引量:5
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作者 Jian-ping Zeng Feng-he Wang +1 位作者 Chen Zhou Xue-dong Gong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期219-225,I0004,共8页
Molecular dynamics simulation has been performed to simulate the interaction between PESA and the (001) face of anhydrite crystal CaSO4 at different temperatures with the presence of various number of H2O molecules.... Molecular dynamics simulation has been performed to simulate the interaction between PESA and the (001) face of anhydrite crystal CaSO4 at different temperatures with the presence of various number of H2O molecules. The results show that PESA can effectively prevent the growth of CaSO4 scale at 323-343 K. At the same temperature, the binding energy between PESA and the (001) face of CaSO4 for systems with various number of H2O has the order of E-bind(OH2O)〉Ebind(200-400H2O)〉E, bind(lOOH2O). For the same system at different temperatures the binding energies are close and are mainly contributed from the Coulomb interaction, including ionic bonds. The bonds are formed between the calcium atoms of anhydrite scale crystal and the Hydrogen bonds are formed between the O oxygen atoms of the carboxyl group of PESA. atoms of the carboxyl group of PESA and the H atoms of H2O. van der Waals interaction is conducive to the stability of the system of PESA, H2O, and CaSO4. The radial distribution functions of O(carbonyl of PESA)-H(H2O), O(CaSO4)-H(H2O), and O(CaSO4)-H(PESA) imply that solvents have effects on the anti-scale performance of PESA to CaSO4. 展开更多
关键词 Polyepoxysuccinic acid Calcium sulphate Molecular dynamics Binding en-ergy Radial distribution function
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Fusing Fixed and Hint Landmarks on Crowd Paths for Automatically Constructing Wi-Fi Fingerprint Database 被引量:2
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作者 HUANG Zhengyong XIA Jun +3 位作者 YU Hui GUAN Yunfeng GAN Xiaoying LIU Jing 《China Communications》 SCIE CSCD 2015年第1期11-24,共14页
In typical Wi-Fi based indoor positioning systems employing fingerprint model,plentiful fingerprints need to be trained by trained experts or technician,which extends labor costs and restricts their promotion.In this ... In typical Wi-Fi based indoor positioning systems employing fingerprint model,plentiful fingerprints need to be trained by trained experts or technician,which extends labor costs and restricts their promotion.In this paper,a novel approach based on crowd paths to solve this problem is presented,which collects and constructs automatically fingerprints database for anonymous buildings through common crowd customers.However,the accuracy degradation problem may be introduced as crowd customers are not professional trained and equipped.Therefore,we define two concepts:fixed landmark and hint landmark,to rectify the fingerprint database in the practical system,in which common corridor crossing points serve as fixed landmark and cross point among different crowd paths serve as hint landmark.Machinelearning techniques are utilized for short range approximation around fixed landmarks and fuzzy logic decision technology is applied for searching hint landmarks in crowd traces space.Besides,the particle filter algorithm is also introduced to smooth the sample points in crowd paths.We implemented the approach on off-the-shelf smartphones and evaluate the performance.Experimental results indicate that the approach can availably construct WiFi fingerprint database without reduce the localization accuracy. 展开更多
关键词 indoor localization fingerprint database construction fixed landmarks hint landmarks particle filter algorithm
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Hooke's Atom in an Arbitrary External Electric Field: Analytical Solutions of Two-Electron Problem by Path Integral Approach
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作者 蔡亮 张萍 +1 位作者 杨涛 潘孝胤 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期565-568,共4页
By using the path integral approach, we investigate the problem of Hooke's atom (two electrons interacting with Coulomb potential in an external harmonic-oscillator potential) in an arbitrary time-dependent electri... By using the path integral approach, we investigate the problem of Hooke's atom (two electrons interacting with Coulomb potential in an external harmonic-oscillator potential) in an arbitrary time-dependent electric field. For a certain infinite set of discrete oscillator frequencies, we obtain the analytical solutions. The ground state polarization of the atom is then calculated. The same result is also obtained through linear response theory. 展开更多
关键词 Hooke's atom path integral PROPAGATOR POLARIZATION
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A Two-phase Solution Algorithm for the Inventory Routing Problem with Time Windows
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作者 Pantelis Z. Lappas Manolis N. Kritikos George D. Ioannou 《Journal of Mathematics and System Science》 2017年第9期237-247,共11页
The main objective of this paper is to propose a two-phase solution algorithm for solving the Inventory Routing Problem with Time Windows (IRPTW), which has not been excessively researched in the literature. The sol... The main objective of this paper is to propose a two-phase solution algorithm for solving the Inventory Routing Problem with Time Windows (IRPTW), which has not been excessively researched in the literature. The solution approach is based on (a) a simple simulation for the planning phase (Phase I) and (b) the Variable Neighborhood Search Algorithm (VNS) for the routing phase (Phase II). Testing instances are established to investigate algorithmic performance, and the computational results are then reported. The computational study underscores the importance of integrating the inventory and vehicle routing decisions. Graphical presentation formats are provided to convey meaningful insights into the problem. 展开更多
关键词 ROUTING Inventory Routing Problem with Time Windows Simple Simulation Variable Neighborhood Search
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Phosphorus Loss from Dry Sloping Lands of Three Gorges Reservoir Area, China 被引量:4
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作者 HU Zheng-Feng GAO Ming +1 位作者 XIE De-Ti WANG Zi-Fang 《Pedosphere》 SCIE CAS CSCD 2013年第3期385-394,共10页
Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus (P) is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farml... Eutrophication in the Three Gorges Reservoir has become a serious issue, and phosphorus (P) is the nutrient thought to be primarily responsible although there are few studies about P loss from the mostly sloping farmlands of the area. This work investigated the amounts and forms of P loss from 9 farmlands with the slopes of 4°, 9°, and 17° in a small watershed, Wangjiagou in Fuling District, Chongqing of China. The slope of the relationship between runoff and rainfall increased with field slope; i.e., there was a significant interaction between the effects of rainfall and field slope on water export. For sediment export by surface runoff, there was no interaction between field slope and rainfall, and the intercept of the relationship between rainfall and sediment loss was significantly different for the 3 slopes. The main P loss was from sediments, regardless of slope. In the runoff water, particulate P was the largest P fraction, and its loss was greatest from the steepest land and least from the flattest. The release of total P and available P from sediments followed the same trend. The P loss during May to July in Wangjiagou was more than 60% of the annual total. 展开更多
关键词 agricultural production area EROSION nutrient loss purple soil soil loss
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TSdb:A database of transporter substrates linking metabolic pathways and transporter systems on a genome scale via their shared substrates 被引量:6
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作者 ZHAO Min CHEN YanMing +1 位作者 QU DaCheng QU Hong 《Science China(Life Sciences)》 SCIE CAS 2011年第1期60-64,共5页
TSdb (http://tsdb.cbi.pku.edu.cn) is the first manually curated central repository that stores formatted information on the substrates of transporters. In total, 37608 transporters with 15075 substrates from 884 organ... TSdb (http://tsdb.cbi.pku.edu.cn) is the first manually curated central repository that stores formatted information on the substrates of transporters. In total, 37608 transporters with 15075 substrates from 884 organisms were curated from UniProt functional annotation. A unique feature of TSdb is that all the substrates are mapped to identifiers from the KEGG Ligand com- pound database. Thus, TSdb links current metabolic pathway schema with compound transporter systems via the shared compounds in the pathways. Furthermore, all the transporter substrates in TSdb are classified according to their biochemical properties, biological roles and subcellular localizations. In addition to the functional annotation of transporters, extensive compound annotation that includes inhibitor information from the KEGG Ligand and BRENDA databases has been integrated, making TSdb a useful source for the discovery of potential inhibitory mechanisms linking transporter substrates and metabolic enzymes. User-friendly web interfaces are designed for easy access, query and download of the data. Text and BLAST searches against all transporters in the database are provided. We will regularly update the substrate data with evidence from new publications. 展开更多
关键词 transporter substrate biological database compound classification compound metabolic network
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