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J1125A型压铸机合型系统不保压故障的排除
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作者 钟友仁 丁永梅 《设备管理与维修》 1991年第8期15-15,共1页
我厂1台北京锻压机床厂生产的J1125A型卧式金属压铸机,从投产起,液压合型系统在合型后即存在轻微降压现象。经使用4年后,情况恶化,发展到合型动作不准,合型后急剧泄压,无法进行生产。压铸机合型系统是电—液—机的综合系统(见附图)。设... 我厂1台北京锻压机床厂生产的J1125A型卧式金属压铸机,从投产起,液压合型系统在合型后即存在轻微降压现象。经使用4年后,情况恶化,发展到合型动作不准,合型后急剧泄压,无法进行生产。压铸机合型系统是电—液—机的综合系统(见附图)。设备在合型后,有一增压过程,待合模力达到规定值时,才允许压射。电磁铁4DT断电而接通3DT(电液换向阀Ⅱ换向)。 展开更多
关键词 压力铸造机 合型系统 故障 排除
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of Au_3Cu-type sublattice system 被引量:3
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作者 谢佑卿 聂耀庄 +2 位作者 李小波 彭红建 刘心笔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第1期211-240,共30页
Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that... Taking Au3Cu-type sublattice system as an example, three discoveries have been presented. First, the fourth barrier to hinder the progress of metal materials science is that today’s researchers do not understand that the Gibbs energy function of an alloy phase should be derived from Gibbs energy partition function constructed of alloy gene sequence and their Gibbs energy sequence. Second, the six rules for establishing alloy gene Gibbs energy partition function have been discovered, and it has been specially proved that the probabilities of structure units occupied at the Gibbs energy levels in the degeneracy factor for calculating configuration entropy should be degenerated as ones of component atoms occupied at the lattice points. Third, the main characteristics unexpected by today’s researchers are as follows. There exists a single-phase boundary curve without two-phase region coexisting by the ordered and disordered phases. The composition and temperature of the top point on the phase-boundary curve are far away from those of the critical point of the Au3Cu compound; At 0 K, the composition of the lowest point on the composition-dependent Gibbs energy curve is notably deviated from that of the Au3Cu compounds. The theoretical limit composition range of long range ordered Au3Cu-type alloys is determined by the first jumping order degree. 展开更多
关键词 Au3Cu compound Au3Cu-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagrams systematic metal materials science
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Alloy gene Gibbs energy partition function and equilibrium holographic network phase diagrams of AuCu_3-type sublattice system 被引量:3
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作者 谢佑卿 李小波 +2 位作者 刘心笔 聂耀庄 彭红建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3585-3610,共26页
Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing exp... Taking AuCu3-type sublattice system as an example, three discoveries have been presented: First, the third barrier hindering the progress in metal materials science is that researchers have got used to recognizing experimental phenomena of alloy phase transitions during extremely slow variation in temperature by equilibrium thinking mode and then taking erroneous knowledge of experimental phenomena as selected information for establishing Gibbs energy function and so-called equilibrium phase diagram. Second, the equilibrium holographic network phase diagrams of AuCu3-type sublattice system may be used to describe systematic correlativity of the composition?temperature-dependent alloy gene arranging structures and complete thermodynamic properties, and to be a standard for studying experimental subequilibrium order-disorder transition. Third, the equilibrium transition of each alloy is a homogeneous single-phase rather than a heterogeneous two-phase, and there exists a single-phase boundary curve without two-phase region of the ordered and disordered phases; the composition and temperature of the top point on the phase-boundary curve are far away from the ones of the critical point of the AuCu3 compound. 展开更多
关键词 AuCu3 compound AuCu3-type sublattice system alloy gene Gibbs energy partition function equilibrium holographic network phase diagram systematic metal materials science
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Modeling method of hybrid systems using extended Petrinets 被引量:1
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作者 周炳海 王世进 陶丽华 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期304-309,共6页
In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, ob... In order to model effectively hybrid systems,a new modeling method of extended Petri nets,which is called extended object-orient hybrid Petri net (EOHPN),is proposed.To deal with the complexity of hybrid systems, object-oriented abstraction mechanisms such as encapsulation and classifications are merged into EOHPN models.To combine the continuous part and discrete part of hybrid systems and to reduce the complexity of hybrid systems,a hybrid Petri net is introduced and extended with object-oriented modeling technology.Development of object models is suggested on the basis of the defined EOHPN.Finally, an application-oriented case is presented to illustrate that how the proposed EOHPN is used to model hybrid systems.The resulting model validates that the EOHPNs can deal with the modeling complexity of hybrid systems. 展开更多
关键词 Petri nets object-oriented model hybrid system MODELING
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Model Compounds of the Mn Cluster in Oxygen-evolving Complex of PSⅡ
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作者 陈昌能 朱红平 +1 位作者 黄德光 刘秋田 《Acta Botanica Sinica》 CSCD 2000年第12期1249-1252,共4页
Six model compounds have been synthesized and used for probing the structural features of the Mn cluster in oxygen_evolving complex (OEC) of photosystem Ⅱ (PSⅡ). The model compounds contain Mn 2(μ_O) 2 and μ_O_... Six model compounds have been synthesized and used for probing the structural features of the Mn cluster in oxygen_evolving complex (OEC) of photosystem Ⅱ (PSⅡ). The model compounds contain Mn 2(μ_O) 2 and μ_O_μ_carboxylato di_manganese structural units, which offer Mn—Mn, Mn……Mn, and Mn—O(N) structural parameters consistent with the corresponding data of the OEC in PSⅡ, implying that the Mn cluster in OEC may possess similar structural features. Two model compounds containing halide anion have been used for discussing the binding of Cl - to Mn in PSⅡ. It is suggested that in the five S states, ligand exchange would lead to the ligation of chloride to Mn in the S states with Mn of higher valence. 展开更多
关键词 PHOTOSYSTEM oxygen-evolving complex model compound manganese cluster
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Global Solutions for a Strongly-coupled Parabolic System with Initial Boundary Values 被引量:2
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作者 XUZhi-fen CHENBin 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期90-100,共11页
In this paper, we consider a strongly-coupled parabolic system with initial boundary values. Under the appropriate conditions, using Gagliard-Nirenberg inequality, Poincare inequality, Gronwall inequality and imbeddin... In this paper, we consider a strongly-coupled parabolic system with initial boundary values. Under the appropriate conditions, using Gagliard-Nirenberg inequality, Poincare inequality, Gronwall inequality and imbedding theorem, we obtain the global existence of solutions. 展开更多
关键词 parabolic equations strongly-coupled initial boundary values global solutions
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Modeling and control of a small solar fuel cell hybrid energy system 被引量:1
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作者 LI Wei ZHU Xin-jian CAO Guang-yi 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期734-740,共7页
This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a stora... This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a storage gas tank and power conditioning unit (PCU). The load is supplied from the PV generator with a fuel cell working in parallel. Excess PV energy when available is converted to hydrogen using an electrolyser for later use in the fuel cell. The individual mathematical model for each component is presented. Control strategy for the system is described. MATLAB/Simulink is used for the simulation of this highly nonlinear hybrid energy system. The simulation results are shown in the paper. 展开更多
关键词 Photovoltaic (PV) Fuel cell ELECTROLYSER Maximum power point tracking
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Saturation influence of control voltage on maglev stationary self-excited vibration 被引量:3
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作者 李金辉 李杰 余佩倡 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期1954-1960,共7页
This work addresses the saturation influence of control voltage on the occurring of self-excited vibration of maglev vehicle-bridge interaction system, which greatly degrades the stability of the levitation control, d... This work addresses the saturation influence of control voltage on the occurring of self-excited vibration of maglev vehicle-bridge interaction system, which greatly degrades the stability of the levitation control, decreases the ride comfort, and restricts the cost of the whole system. Firstly, the interaction model of vehicle-bridge system is developed. Based on the interaction model, the relationship between the control voltage and vibration frequency is solved. Then, the variation of the effective direct component and fundamental harmonic are discussed. Furthermore, from the perspective of energy transmission between the levitation system and bridge, the principle underlying the self-excited vibration is explored, and the influence on the stability is discussed. Finally, in terms of the variation of the characteristic roots, the influence is analyzed further and some conclusions are obtained. This study provides a theoretical guidance for mastering the self-excited vibration problems. 展开更多
关键词 MAGLEV LEVITATION SATURATION self-excited vibration
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Role of Anthropogenic Volatile Organic Compounds and Nitrogen Oxides as Ozone Precursors in the Wintertime over East Asia 被引量:3
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作者 ZHANGMeigen ItsushiUno 《Journal of Ocean University of Qingdao》 2002年第1期45-49,共5页
As an exercise in model sensitivity, the Models-3 Community Multiscale Air Quality (CMAQ) modeling system with meteorological fields from the Regional Atmospheric Modeling System (RAMS) was applied to study the respon... As an exercise in model sensitivity, the Models-3 Community Multiscale Air Quality (CMAQ) modeling system with meteorological fields from the Regional Atmospheric Modeling System (RAMS) was applied to study the response of photochemical oxidants to systematic increases in anthropogenic volatile organic compounds (VOC) and nitrogen oxides (NO x) emissions in January 1997 over East Asia. Three simulations-one base case and two sensitivity simulations were carried out. Two sensitivity simulations were performed by assuming a 35% separate increase in anthropogenic VOC and NO x emissions comparing with the base case. Biogenic VOC emissions were held constant across the sensitivity simulations. To evaluate the model performance, ozone mixing ratios (O 3) from the base case simulation were compared with surface observations at five remote sites in Japan, and it was found that the model reproduces most of the important features in the observations. Monthly average O 3 concentrations in the daytime were examined to gain an understanding of how the increase in anthropogenic emissions affected the overall chemical system for each sensitivity simulation. 展开更多
关键词 Community Multiscale Air Quality (CMAQ) Regional Atmospheric Modeling System (RAMS) East Asia
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Theoretical coupling longitudinal-transverse model and experimental verification of transverse vibration of rope for multi-rope friction hoisting system 被引量:4
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作者 Juan Wu Ziming Kou 《International Journal of Coal Science & Technology》 EI 2016年第1期77-84,共8页
Using the mass of time-varying length balance rope focused on the hoisting conveyance, the coupling longi- tudinal-transverse model of mine friction hoist was established by using of the Hamilton's principle. The mod... Using the mass of time-varying length balance rope focused on the hoisting conveyance, the coupling longi- tudinal-transverse model of mine friction hoist was established by using of the Hamilton's principle. The modified Galerkin's method was used to discretize partial differential Eqs. The mine hoisting system was used to the example to analysis the relation between the load, velocity and transverse vibration of rope. The in situ tests were illustrated to evaluate the proposed mathematical model. The results showed that the modeling method can well represent the transverse vibration of rope. 展开更多
关键词 Hoisting system VIBRATION ROPE Longitudinal-transverse COUPLING
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Development of two microsatellite multiplex PCR systems for high throughput genotyping in Populus euphratica 被引量:4
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作者 Eusemann Pascal Fehrenz Steffen Schnittler Martin 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期195-198,共4页
Eighteen microsatellite primer pairs previously developed at Oak Ridge National Laboratory for Populus tremuloides Michx. and Populus trichocarpa Tort. & Gray were screened for amplification in Euphrates poplar, Popu... Eighteen microsatellite primer pairs previously developed at Oak Ridge National Laboratory for Populus tremuloides Michx. and Populus trichocarpa Tort. & Gray were screened for amplification in Euphrates poplar, Populus euphratica Oliv. Thirteen loci were found to express polymorphisms ranging from two to 17 alleles. The eight most variable loci were selected to set up and optimize two multiplex polymerase chain reaction (PCR) assays. Three populations containing altogether 436 trees were used to characterize the selected loci and ascertain their applicability for parentage analysis and genotyping studies. Through cross-checking of clonal identity against sex of the genotyped trees we estimated the maximum error rate for merging genotypes to be less than 0.045. 展开更多
关键词 clone identification Euphrates poplar genetic fingerprint parentage analysis population structure SSR primers
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Optimization of Wind-Marine Hybrid Power System Configuration Based on Genetic Algorithm 被引量:1
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作者 SHI Hongda LI Linna ZHAO Chenyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期709-715,共7页
Multi-energy power systems can use energy generated from various sources to improve power generation reliability.This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use... Multi-energy power systems can use energy generated from various sources to improve power generation reliability.This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use on a remote island,where the configuration is optimized using a genetic algorithm.A mixed integer programming model is used and a novel object function,including cost and power generation,is proposed to solve the boundary problem caused by existence of two goals.Using this model,the final optimized result is found to have a good fit with local resources. 展开更多
关键词 genetic algorithm cost-power generation function multi-energy system marine energy
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Thermo-hydro-mechanical coupled mathematical model for controlling the pre-mining coal seam gas extraction with slotted boreholes 被引量:11
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作者 Xue Yi Gao Feng +3 位作者 Gao Yanan Liang Xin Zhang Zhizhen Xing Yan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第3期473-479,共7页
Drainage influence radius is the basic parameter for borehole arrangement, while the effect of high pressure water jet slotting technology on borehole drainage influence radius has not been studied systematically. In ... Drainage influence radius is the basic parameter for borehole arrangement, while the effect of high pressure water jet slotting technology on borehole drainage influence radius has not been studied systematically. In this paper, a fully thermo-hydro-mechanical(THM) coupled model which represents the non-linear responses of gas extraction was implemented to demonstrate the reliability of this model through history data matching. Based on this model, the susceptibilities of gas extraction with single slotted borehole, including the permeability, the gas pressure, the temperature, the coal adsorption characteristics and the radius of slot, were quantified through a series of simulations. The simulation results revealed that increasing the permeability, initial gas pressure and temperature could develop the influence radius of single slotted borehole. This finite element model and its simulation results can improve the understanding of the coal-gas interactions of underground gas drainage and provide a scientific basis for the optimization of drainage systems. 展开更多
关键词 Coal seam gasGas extractionThermo-hydro-mechanical modelSlotted boreholes
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Integrated Statistical and Engineering Process Control Based on Smooth Transition Autoregressive Model 被引量:1
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作者 张晓蕾 何桢 《Transactions of Tianjin University》 EI CAS 2013年第2期147-156,共10页
Traditional studies on integrated statistical process control and engineering process control (SPC-EPC) are based on linear autoregressive integrated moving average (ARIMA) time series models to describe the dynamic n... Traditional studies on integrated statistical process control and engineering process control (SPC-EPC) are based on linear autoregressive integrated moving average (ARIMA) time series models to describe the dynamic noise of the system.However,linear models sometimes are unable to model complex nonlinear autocorrelation.To solve this problem,this paper presents an integrated SPC-EPC method based on smooth transition autoregressive (STAR) time series model,and builds a minimum mean squared error (MMSE) controller as well as an integrated SPC-EPC control system.The performance of this method for checking the trend and sustained shift is analyzed.The simulation results indicate that this integrated SPC-EPC control method based on STAR model is effective in controlling complex nonlinear systems. 展开更多
关键词 statistical process control engineering process control time series STAR model AUTOCORRELATION
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Multi-objective intelligent coordinating optimization blending system based on qualitative and quantitative synthetic model 被引量:3
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作者 王雅琳 马杰 +2 位作者 桂卫华 阳春华 张传福 《Journal of Central South University of Technology》 EI 2006年第5期552-557,共6页
A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism a... A multi-objective intelligent coordinating optimization strategy based on qualitative and quantitative synthetic model for Pb-Zn sintering blending process was proposed to obtain optimal mixture ratio. The mechanism and neural network quantitative models for predicting compositions and rule models for expert reasoning were constructed based on statistical data and empirical knowledge. An expert reasoning method based on these models were proposed to solve blending optimization problem, including multi-objective optimization for the first blending process and area optimization for the second blending process, and to determine optimal mixture ratio which will meet the requirement of intelligent coordination. The results show that the qualified rates of agglomerate Pb, Zn and S compositions are increased by 7.1%, 6.5% and 6.9%, respectively, and the fluctuation of sintering permeability is reduced by 7.0%, which effectively stabilizes the agglomerate compositions and the permeability. 展开更多
关键词 Pb-Zn sintering blending process qualitative and quantitative synthetic model multi-objectiveoptimization area optimization intelligent coordination
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Nonequivalent Similarity Reductions and Exact Solutions for Coupled Burgers-Type Equations 被引量:2
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作者 M.H.M.Moussa R.A.K.Omar +1 位作者 Rehab M.El-Shiekh H.R.El-Melegy 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期1-4,共4页
Using the machinery of Lie group analysis,the nonlinear system of coupled Burgers-type equations is studied.Using the infinitesimal generators in the optimal system of subalgebra of the said Lie algebras,it leads to t... Using the machinery of Lie group analysis,the nonlinear system of coupled Burgers-type equations is studied.Using the infinitesimal generators in the optimal system of subalgebra of the said Lie algebras,it leads to two nonequivalent similarity transformations by using it we obtain two reductions in the form of system of nonlinear ordinary differential equations.The search for solutions of these systems by using the G'/G-method has yielded certain exact solutions expressed by rational functions,hyperbolic functions,and trigonometric functions.Some figures are given to show the properties of the solutions. 展开更多
关键词 symmetry method G/G-method coupled Burgers-type equations exact solutions
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Hybrid tracking model and GSLM based neural network for crowd behavior recognition
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作者 Manoj Kumar Charul Bhatnagar 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期2071-2081,共11页
Crowd behaviors analysis is the‘state of art’research topic in the field of computer vision which provides applications in video surveillance to crowd safety,event detection,security,etc.Literature presents some of ... Crowd behaviors analysis is the‘state of art’research topic in the field of computer vision which provides applications in video surveillance to crowd safety,event detection,security,etc.Literature presents some of the works related to crowd behavior detection and analysis.In crowd behavior detection,varying density of crowds and motion patterns appears to be complex occlusions for the researchers.This work presents a novel crowd behavior detection system to improve these restrictions.The proposed crowd behavior detection system is developed using hybrid tracking model and integrated features enabled neural network.The object movement and activity in the proposed crowded behavior detection system is assessed using proposed GSLM-based neural network.GSLM based neural network is developed by integrating the gravitational search algorithm with LM algorithm of the neural network to increase the learning process of the network.The performance of the proposed crowd behavior detection system is validated over five different videos and analyzed using accuracy.The experimentation results in the crowd behavior detection with a maximum accuracy of 93%which proves the efficacy of the proposed system in video surveillance with security concerns. 展开更多
关键词 crowd video crowd bohavior TRACKING RECOGNITION neural network gravitational search algorithm
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Integrated assessment model of water resources constraint intensity on urbanization in arid area 被引量:5
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作者 鲍超 方创琳 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期273-286,共14页
Water has become a key restricting factor of the urbanization process in developing arid areas.Based on qualitative and quantitative methods,we constructed an integrated in-dicator system to assess the status of water... Water has become a key restricting factor of the urbanization process in developing arid areas.Based on qualitative and quantitative methods,we constructed an integrated in-dicator system to assess the status of water resources and urbanization system in arid area,and established an AHP model reformed by entropy technology to evaluate the temporal and spatial variations of water resources constraint intensity on urbanization.This model is ap-plied to the Hexi Corridor,a typical arid area in NW China.Results show that,water resources constraint intensity on urbanization in the Hexi Corridor is bigger in the east and smaller in the west.It has changed from the less strong constraint type into the strong constraint type from 1985 to 2005,yet it decreased appreciably in recent years.At present,most areas in the Hexi Corridor belong to the less strong or strong constraint type.Through rational adjustment of water resources and urbanization system,the Hexi Corridor can still promote water resources sustainable utilization and accelerate the urbanization process.This study suggests that the integrated assessment model of water resources constraint intensity on urbanization is an effective method to analyze the conflicts between water resources and urbanization system in arid area. 展开更多
关键词 water resources constraint intensity (WRCI) URBANIZATION AHP model temporal and spatial variation Hexi Corridor
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Apparatus Prototype for Purposes of Teaching in Bio-digesters
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作者 Martin Trinidad Martinez Garcia Jose Luis Magana Ramirez Rodrigo Mauricio Rodriguez Cuellar 《Journal of Chemistry and Chemical Engineering》 2014年第8期834-840,共7页
A mathematical model is developed based on a simplified mechanism of anaerobic digestion. The main objective is to quantitatively analyze the digestion process to optimize operating conditions and maintenance of this ... A mathematical model is developed based on a simplified mechanism of anaerobic digestion. The main objective is to quantitatively analyze the digestion process to optimize operating conditions and maintenance of this equipment, which could be used to test different materials and be able to apply these results to the possible scaling to bio-digesters installed in the field. The experiments were carried out in a hybrid system bio-digester photovoltaic cells. The bio-digester is made of stainless steel with dimensions to treat an average of 10 kg of raw material and produce biogas from different organic materials. The reactor has been conditioned with temperature sensors, pressure and methane gas that allow monitoring the concentration of the gas and the conditions of operation during the time of digestion. The system has a photovoltaic array to provide the energy required to keep the temperature constant, The experiment was conducted using materials such as goat manure mixed with household waste, and various formulations of these materials were prepared. The experimental results were used to test the mathematical model. 展开更多
关键词 Biodigester anaerobic digestion methane production biomass treatment.
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Overview on high-resolution ocean modeling in JAMSTEC
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作者 Michio Kawamiya 《Engineering Sciences》 EI 2014年第2期43-44,共2页
In view of the importance of ocean component for representing climate change,efforts are underway to implement a high-resolution nesting model system in Model for Interdisciplinary Research on Climate(MIROC) for the N... In view of the importance of ocean component for representing climate change,efforts are underway to implement a high-resolution nesting model system in Model for Interdisciplinary Research on Climate(MIROC) for the North Pacific using the same ocean model as used in the coupled model MIROC5. By comparing double(10 km for the northwestern Pacific,50 km for the rest of the Pacific) and triple(double nesting plus 2 km resolution near Japan) nesting,it turns out that relative vorticity is drastically enhanced near Japan with 2 km resolution. It is hoped that such an elaborated nesting system will reveal detailed processes for the ocean heat uptake by,e.g.,intermediate water and mode water formation for which the"perturbed region"near Japan is the key region. 展开更多
关键词 K computer earth simulator II eddy-resolving ocean model nesting model
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