This paper analyzes of the bottleneck to influence the running efficiency of educational administration system in universities and colleges,and from the system deployment architecture, server configuration, database S...This paper analyzes of the bottleneck to influence the running efficiency of educational administration system in universities and colleges,and from the system deployment architecture, server configuration, database SQL statement optimization and other aspects, it puts forwards the optimization scheme.展开更多
The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than...The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than overlay network.Upgrade from existing network to destination network requires a multitude of preparations and tests.Cities and provinces upgrade their networks from the aspects of Service Control Point(SCP),Home Location Register(HLR),Mobile Switching Center(MSC),Gateway Mobile Switching Center(GMSC)and subsciption information through different processes.In order to fully realize the destination network after upgrading the accounting systems,the bill collection have to be rebuilt while the value-added services have to be upgraded.However,many difficulties,such as the Originating-CAMEL Subscription Information(O-CSI),the Terminating-CAMEL Subscription Information(T-CSI),and the special access number optimization,which all needs a particular solution,exist in upgrading.展开更多
A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional pur...A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional purification process of flue gas produced during waste incineration( SNCR denitrification +dry/semi-dry deacidification + adsorption of dioxins and heavy metals by activated carbon + bag dusting) has been unable to meet this requirement,and the newly added wet deacidification and SCR denitrification processes can meet this requirement. The flue gas purification process was optimized,and two feasible schemes were compared to choose the better one.展开更多
Based on the demands for crashworthiness and lightweight in the passive safety of transportation vehicles,metal-fiber reinforced polymer(FRP)hybrid thin-walled tubes(MFHTWTs)integrate the toughness,strength and lightw...Based on the demands for crashworthiness and lightweight in the passive safety of transportation vehicles,metal-fiber reinforced polymer(FRP)hybrid thin-walled tubes(MFHTWTs)integrate the toughness,strength and lightweight of two distinct material characteristics.MFHTWTs can achieve energy absorption through the coupling of material plastic deformation and fracture,demonstrating significant engineering value in passive safety.This review provides a comprehensive examination of the crashworthiness topology optimization of MFHTWTs,aiming to demonstrate that a deeply integrated approach combining topology and parameter opti-mization can realize an optimal design method for MFHTWTs,thereby maximizing the functional utilization of limited material.Firstly,the review highlights the crashworthiness topology optimization methods(CTOMs)based on thin-walled structures.With a particular focus on metal,the review discusses both the practical ap-plicability and limitations of CTOMs under crash conditions.Additionally,based on the methodology of the equivalent static load method(ESLM),the review emphasizes that topology optimization methods considering continuous fiber paths and multi-material interface connections are also applicable to the crashworthiness op-timization of MFHTWTs.Furthermore,to couple structural parameters and configuration characteristics,in-tegrated topology optimization methods,including parameter optimization,are proposed to provide a valuable reference for the global optimization of MFHTWTs.Thus,these methods can establish the mapping relationship between key parameters and the structural energy absorption capacity.展开更多
This study develops an innovative methodology for CO2 flooding optimization in tight oil reservoirs through a novel hybrid analytical framework that effectively combines Grey Relational Analysis(GRA),Entropy Weight...This study develops an innovative methodology for CO2 flooding optimization in tight oil reservoirs through a novel hybrid analytical framework that effectively combines Grey Relational Analysis(GRA),Entropy Weight Method(EWM),and Analytic Hierarchy Process(AHP)in a logically structured decisionmaking process.The research achieves significant methodological advancement by intelligently integrating type-2 fuzzy logic with artificial neural networks to establish robust high-precision predictive models,while developing a comprehensive optimization system that innovatively correlates geologicalfluid characteristics with engineering parameters through systematic parameter coupling.The proposed framework introduces a new classification-based approach to formulate specific optimization criteria for different reservoir grades.Detailed comparative studies confirm that the staggered well-fracture network configuration provides optimal performance,offering clear technical advantages over alternative patterns in terms of both productivity enhancement and recovery efficiency.The framework's distinctive analytical capability enables a thorough evaluation of key controlling factors,with rigorous sensitivity analysis identifying porosity,oil saturation,effective reservoir thickness,crude oil viscosity,and crude oil density as dominant geological controls in Block W,while precisely quantifying the impact of operational parameters including fracturing clusters,horizontal interval length,and total gas injection volume.The optimization process employs an enhanced Particle Swarm-Genetic Hybrid System,where 151 iterations of intelligent algorithm refinement yield field-validated performance improvements.The resulting scheme demonstrates consistent effectiveness across reservoir grades,delivering 10%–25%cumulative production increase and over 8%recovery factor enhancement.This multidisciplinary approach provides a technically sound and practically viable solution for tight oil reservoir management,establishing a new methodological standard for CO2 flooding optimization that successfully overcomes several key limitations of traditional analytical approaches through its integrated,datadriven methodology.展开更多
This paper takes the quality management of raw material delivery in construction projects as its research subject, systematically proposing an improvement plan to address prominent issues currently existing in the ope...This paper takes the quality management of raw material delivery in construction projects as its research subject, systematically proposing an improvement plan to address prominent issues currently existing in the operation of the control system. The article first outlines the significance, core components, and basic procedures of quality control for incoming construction materials, clarifying their fundamental role in ensuring overall project quality and safety. It then provides a detailed analysis of the current operational status of the existing system, identifying specific shortcomings and challenges in supplier management, procurement processes, on-site inspection and testing, as well as quality documentation and traceability. To resolve these challenges, the study focuses on developing a comprehensive improvement plan covering three key aspects. First, it proposes establishing a rational and rigorous supplier admission and dynamic grading management system to strictly control material quality at the source. Second, it advocates improving and strengthening standardized incoming inspection procedures to ensure the standardization and effectiveness of acceptance processes. Third, it recommends building a comprehensive quality information tracking system that covers the entire production process, leveraging modern technological tools to enhance transparency and operational efficiency. The paper elaborates on the specific implementation steps and critical stages of this improvement plan, and presents relevant personnel arrangements, regulations, and technical support measures, offering insights into its expected outcomes in enhancing control effectiveness, reducing quality risks, and enabling full-process traceability. The goal of this research is to provide construction enterprises with theoretical foundations and practical methodologies for optimizing the quality management of incoming raw materials.展开更多
Fishery-independent surveys are often used for collecting high quality biological and ecological data to support fisheries management. A careful optimization of fishery-independent survey design is necessary to improv...Fishery-independent surveys are often used for collecting high quality biological and ecological data to support fisheries management. A careful optimization of fishery-independent survey design is necessary to improve the precision of survey estimates with cost-effective sampling efforts. We developed a simulation approach to evaluate and optimize the stratification scheme for a fishery-independent survey with multiple goals including estimation of abundance indices of individual species and species diversity indices. We compared the performances of the sampling designs with different stratification schemes for different goals over different months. Gains in precision of survey estimates from the stratification schemes were acquired compared to simple random sampling design for most indices. The stratification scheme with five strata performed the best. This study showed that the loss of precision of survey estimates due to the reduction of sampling efforts could be compensated by improved stratification schemes, which would reduce the cost and negative impacts of survey trawling on those species with low abundance in the fishery-independent survey. This study also suggests that optimization of a survey design differed with different survey objectives. A post-survey analysis can improve the stratification scheme of fishery-independent survey designs.展开更多
In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio seque...In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio sequence as an optimization objective and simple shifting logic between adjacent gears through operating only one shifting element as a constraint condition, a fitness function of shifting element schemes was proposed. ZF-8AT shifting element schemes were optimized based on GA work-box of MATLAB, and the feasibility of the optimization algorithm was verified.展开更多
There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk f...There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk factors of construction diversion system with discharge control feature as well as their composition. And the risk factors include the upstream operational reservoir discharge control, the interval flood and branch flood and the diversion system itself. And then based on analyzing of the conversion relation between risk index and investment index of diversion scheme, the risk control and conversion principals of diversion system are put forward, and the feasible diversion scheme model is built. At last, the risk and economic evaluation and scheme economic feasibility analysis method of diversion scheme are shown by an example of construction diversion scheme optimization with the discharge control condition of upstream hydropower station. The study is valuable for establishment and optimization of construction diversion scheme with upstream reservoir discharge control.展开更多
The so-called construction scheme optimization is to adjust the original good construction scheme, such as eliminating hidden dangers, simplifying the structure, reducing the cost, etc., thus simplifying the original ...The so-called construction scheme optimization is to adjust the original good construction scheme, such as eliminating hidden dangers, simplifying the structure, reducing the cost, etc., thus simplifying the original scheme and reducing the construction cost. Because the construction plan is different, the construction period will be different and the machines and tools required will be different, thus the expenses incurred will also be different. Therefore, the on-site technical engineer should put forward a technically advanced, technically reasonable and organizationally capable construction plan based on the contract period, taking into account factors such as the scale, nature, complexity, site conditions, equipment conditions and personnel quality of the project, and strive to reduce the project cost. In this paper, from the aspects of the determination of construction methods, the selection of construction machines and tools, the arrangement of construction sequence and the organization and arrangement of construction, the application of the optimization method of construction scheme in the cost management of engineering projects, such as the formulation of advanced, economical and reasonable construction scheme, the rational selection of machinery and the full play of the efficiency of machinery, is analyzed, and the importance of construction scheme in the cost management of projects is expounded.展开更多
Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the eff...Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the effects of perforation position and length on hydraulic fracture propagation in coal measures of the Lin-Xing block,China.Based on field data,three lithologic combinations are simulated:1)a thick section of coal seam sandwiched by sandstones;2)a thin coal seam layer overlay by gas-bearing tight sandstone;3)two coal seams separated by a thin layer of sandstone.Our simulation shows that perforation position and length in multi-layer reservoirs play a major role in hydraulic fracture propagation.Achieving maximum stimulated volume requires consideration of lithologic sequence,coal seam thickness,stress states,and rock properties.To improve the combined gas production in coal measure strata,it is possible to simultaneously stimulate multiple coal seams or adjacent gas-bearing sandstones.In these cases,perforation location and length also significantly impact fracture propagation,and therefore should be carefully designed.Our simulation results using 3 D lattice algorithm are qualitatively consistent with laboratory physical simulation.3 D lattice models can be used to effectively simulate the fracture propagation through layers in coal measure strata.The numerical results provide guidance for perforation optimization in the hydraulic fracturing of coal measure strata.展开更多
Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum chann...Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum channels. They gave the maximal probability of successful teleportation. Here we find that their operation is not the optimal and the successful probability of the teleportation is not maximum. Moreover, we give the optimal schemes operation and obtain maximal successful probability for teleportation.展开更多
China's Rural Cooperative Medical System collapsed alongside communal farming at the end of the Maoist period in 1976, leaving most farmers vulnerable[1]. In rural areas, where 80% of people have been without health ...China's Rural Cooperative Medical System collapsed alongside communal farming at the end of the Maoist period in 1976, leaving most farmers vulnerable[1]. In rural areas, where 80% of people have been without health insurance of any kind, illness has emerged as a leading cause of poverty[24]. To address the poor state of health care among the rural population, in 2003 the Chinese government launched the New Rural Cooperative Medical System (NCMS),展开更多
In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separat...In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separation spring-driven opening scheme is proposed to achieve rapid and reliable opening of the front cover.The mathematical model of the opening process of the front cover is established by the rigid body dynamics theory.To establish a response surface model to optimize the opening scheme,three main influencing factors of the opening process are obtained through the designed experiments,including the pre-compression,the stiffness of the thrust spring,and the thrust spring force arm length.In addition,the prescribed kinematic law was taken as constraint,and the smaller thrust spring preliminary pressure and angular velocity was taken as optimization expectations.The results show that the opening scheme meets the design requirements on opening process well.It also shows that the optimized scheme can reduce the kinetic energy of the front cover,and the impact on the canister effectively,achieving a reliable and rapid opening of the front cover.展开更多
The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of ...The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of importance in both theory and practice in water resource systems engineering. In order to achieve consistency and eliminate the dimensions of fuzzy qualitative and fuzzy quantitative evaluation indexes, to determine the weights of the indexes objectively, and to increase the differences among the comprehensive evaluation index values of water transportation project schemes, a projection pursuit method, named FPRM-PP for short, was developed in this work for selecting the optimal water transportation project scheme based on the fuzzy preference relation matrix. The research results show that FPRM-PP is intuitive and practical, the correction range of the fuzzy rained is both stable and accurate; preference relation matrix A it produces is relatively small, and the result obtherefore FPRM-PP can be widely used in the optimal selection of different multi-factor decision-making schemes.展开更多
This study develops an optimized finite difference iterative (OFDI) scheme for the two-dimensional (2D) viscoelastic wave equation. The OFDI scheme is obtained using a proper orthogonal decomposition (POD) metho...This study develops an optimized finite difference iterative (OFDI) scheme for the two-dimensional (2D) viscoelastic wave equation. The OFDI scheme is obtained using a proper orthogonal decomposition (POD) method. It has sufficiently high accuracy with very few unknowns for the 2D viscoelastic wave equation. Existence, stability, and convergence of the OFDI solutions are analyzed. Numerical simulations verify efficiency and feasibility of the proposed scheme.展开更多
Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categor...Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categorize the correlation extent of compared sequences and a certain reference sequence in a system with uncertain information. It is applied to evaluating and selecting AC cold/heat sources from four main aspects, which are technology, economy, reliability, and operation and management. Case study shows that the result for selecting AC cold/heat sources with the GRA method can be more reasonable and convincible. Thus it offers a new approach for designers in heating, ventilating and air conditioning field to compare and evaluate different AC cold/heat sou rces.展开更多
In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, throu...In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, through computer simulation experiment were analyzed, and optimization design, through the real car collision test, make the concrete guardrail after heightening structure satisfies the requirement of the safety performance of current specification. The results show that the protective performance of the two guardrail schemes meets the requirements of the current guardrail evaluation standards through the computer simulation experiment. Through the optimized design of scheme 1, the actual car crash test proves that the enhanced structure of Minhua TYPE II concrete guardrail can meet the requirements of safety performance evaluation. The research results provide an important basis for the transformation of the guardrail and the revision of the current design of expressway in China.展开更多
The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicabili...The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicability and reliability of upward recursive formula in principle is amended.An optimal scheme of upward-and downward-joint recursions has been developed for the sequential F(z) computations.No additional accuracy is needed with the fundamental term of recursion because the absolute error of Fn(z) always decreases with the recursive approach.The scheme can be employed in modifying any of existent subprograms for Fn computations.In the case of p-d-f-and g-type Gaussians,combining this method with Schaad's formulas can reduce,at least,the additive operations by a factor 40%;the multiplicative and exponential operations by a factor 60%.展开更多
AT the present stage, the urban traffic system facing the problem of road congestion is becoming more serious in this background, the need to improve the existing urban traffic problems, set scientific traffic plannin...AT the present stage, the urban traffic system facing the problem of road congestion is becoming more serious in this background, the need to improve the existing urban traffic problems, set scientific traffic planning scheme with the help of micro traffic engineering technology, cooperate with micro traffic simulation technology to complete the problem of traffic congestion. This paper takes the above content as the core, analyzes the actual cases and scientifically verifies the simulation research results combined with the actual project, and finally explains the specific application of micro-traffic engineering technology in urban traffic engineering improvement in detail.展开更多
基金Acknowledgement Research of the nature science foundation of Shandong province has a triangular surface modeling and control display representation(No. ZR2012FL05)
摘要This paper analyzes of the bottleneck to influence the running efficiency of educational administration system in universities and colleges,and from the system deployment architecture, server configuration, database SQL statement optimization and other aspects, it puts forwards the optimization scheme.
摘要The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than overlay network.Upgrade from existing network to destination network requires a multitude of preparations and tests.Cities and provinces upgrade their networks from the aspects of Service Control Point(SCP),Home Location Register(HLR),Mobile Switching Center(MSC),Gateway Mobile Switching Center(GMSC)and subsciption information through different processes.In order to fully realize the destination network after upgrading the accounting systems,the bill collection have to be rebuilt while the value-added services have to be upgraded.However,many difficulties,such as the Originating-CAMEL Subscription Information(O-CSI),the Terminating-CAMEL Subscription Information(T-CSI),and the special access number optimization,which all needs a particular solution,exist in upgrading.
摘要A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional purification process of flue gas produced during waste incineration( SNCR denitrification +dry/semi-dry deacidification + adsorption of dioxins and heavy metals by activated carbon + bag dusting) has been unable to meet this requirement,and the newly added wet deacidification and SCR denitrification processes can meet this requirement. The flue gas purification process was optimized,and two feasible schemes were compared to choose the better one.
基金Supported by National Natural Science Foundation of China(Grant Nos.52202431,52172353).
摘要Based on the demands for crashworthiness and lightweight in the passive safety of transportation vehicles,metal-fiber reinforced polymer(FRP)hybrid thin-walled tubes(MFHTWTs)integrate the toughness,strength and lightweight of two distinct material characteristics.MFHTWTs can achieve energy absorption through the coupling of material plastic deformation and fracture,demonstrating significant engineering value in passive safety.This review provides a comprehensive examination of the crashworthiness topology optimization of MFHTWTs,aiming to demonstrate that a deeply integrated approach combining topology and parameter opti-mization can realize an optimal design method for MFHTWTs,thereby maximizing the functional utilization of limited material.Firstly,the review highlights the crashworthiness topology optimization methods(CTOMs)based on thin-walled structures.With a particular focus on metal,the review discusses both the practical ap-plicability and limitations of CTOMs under crash conditions.Additionally,based on the methodology of the equivalent static load method(ESLM),the review emphasizes that topology optimization methods considering continuous fiber paths and multi-material interface connections are also applicable to the crashworthiness op-timization of MFHTWTs.Furthermore,to couple structural parameters and configuration characteristics,in-tegrated topology optimization methods,including parameter optimization,are proposed to provide a valuable reference for the global optimization of MFHTWTs.Thus,these methods can establish the mapping relationship between key parameters and the structural energy absorption capacity.
基金funded by the Youth Scienceof the National Natural Science Foundation of China(No.52204070)。
摘要This study develops an innovative methodology for CO2 flooding optimization in tight oil reservoirs through a novel hybrid analytical framework that effectively combines Grey Relational Analysis(GRA),Entropy Weight Method(EWM),and Analytic Hierarchy Process(AHP)in a logically structured decisionmaking process.The research achieves significant methodological advancement by intelligently integrating type-2 fuzzy logic with artificial neural networks to establish robust high-precision predictive models,while developing a comprehensive optimization system that innovatively correlates geologicalfluid characteristics with engineering parameters through systematic parameter coupling.The proposed framework introduces a new classification-based approach to formulate specific optimization criteria for different reservoir grades.Detailed comparative studies confirm that the staggered well-fracture network configuration provides optimal performance,offering clear technical advantages over alternative patterns in terms of both productivity enhancement and recovery efficiency.The framework's distinctive analytical capability enables a thorough evaluation of key controlling factors,with rigorous sensitivity analysis identifying porosity,oil saturation,effective reservoir thickness,crude oil viscosity,and crude oil density as dominant geological controls in Block W,while precisely quantifying the impact of operational parameters including fracturing clusters,horizontal interval length,and total gas injection volume.The optimization process employs an enhanced Particle Swarm-Genetic Hybrid System,where 151 iterations of intelligent algorithm refinement yield field-validated performance improvements.The resulting scheme demonstrates consistent effectiveness across reservoir grades,delivering 10%–25%cumulative production increase and over 8%recovery factor enhancement.This multidisciplinary approach provides a technically sound and practically viable solution for tight oil reservoir management,establishing a new methodological standard for CO2 flooding optimization that successfully overcomes several key limitations of traditional analytical approaches through its integrated,datadriven methodology.
摘要This paper takes the quality management of raw material delivery in construction projects as its research subject, systematically proposing an improvement plan to address prominent issues currently existing in the operation of the control system. The article first outlines the significance, core components, and basic procedures of quality control for incoming construction materials, clarifying their fundamental role in ensuring overall project quality and safety. It then provides a detailed analysis of the current operational status of the existing system, identifying specific shortcomings and challenges in supplier management, procurement processes, on-site inspection and testing, as well as quality documentation and traceability. To resolve these challenges, the study focuses on developing a comprehensive improvement plan covering three key aspects. First, it proposes establishing a rational and rigorous supplier admission and dynamic grading management system to strictly control material quality at the source. Second, it advocates improving and strengthening standardized incoming inspection procedures to ensure the standardization and effectiveness of acceptance processes. Third, it recommends building a comprehensive quality information tracking system that covers the entire production process, leveraging modern technological tools to enhance transparency and operational efficiency. The paper elaborates on the specific implementation steps and critical stages of this improvement plan, and presents relevant personnel arrangements, regulations, and technical support measures, offering insights into its expected outcomes in enhancing control effectiveness, reducing quality risks, and enabling full-process traceability. The goal of this research is to provide construction enterprises with theoretical foundations and practical methodologies for optimizing the quality management of incoming raw materials.
基金The Public Science and Technology Research Funds Projects of Ocean under contract No.201305030the Specialized Research Fund for the Doctoral Program of Higher Education under contract No.20120132130001
摘要Fishery-independent surveys are often used for collecting high quality biological and ecological data to support fisheries management. A careful optimization of fishery-independent survey design is necessary to improve the precision of survey estimates with cost-effective sampling efforts. We developed a simulation approach to evaluate and optimize the stratification scheme for a fishery-independent survey with multiple goals including estimation of abundance indices of individual species and species diversity indices. We compared the performances of the sampling designs with different stratification schemes for different goals over different months. Gains in precision of survey estimates from the stratification schemes were acquired compared to simple random sampling design for most indices. The stratification scheme with five strata performed the best. This study showed that the loss of precision of survey estimates due to the reduction of sampling efforts could be compensated by improved stratification schemes, which would reduce the cost and negative impacts of survey trawling on those species with low abundance in the fishery-independent survey. This study also suggests that optimization of a survey design differed with different survey objectives. A post-survey analysis can improve the stratification scheme of fishery-independent survey designs.
基金Project(2011BAG09B00)supported by the National Science and Technology Support Program,China
摘要In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio sequence as an optimization objective and simple shifting logic between adjacent gears through operating only one shifting element as a constraint condition, a fitness function of shifting element schemes was proposed. ZF-8AT shifting element schemes were optimized based on GA work-box of MATLAB, and the feasibility of the optimization algorithm was verified.
基金National Natural Science Foundation of China ( No. 10902078 and No. 51079115)
摘要There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk factors of construction diversion system with discharge control feature as well as their composition. And the risk factors include the upstream operational reservoir discharge control, the interval flood and branch flood and the diversion system itself. And then based on analyzing of the conversion relation between risk index and investment index of diversion scheme, the risk control and conversion principals of diversion system are put forward, and the feasible diversion scheme model is built. At last, the risk and economic evaluation and scheme economic feasibility analysis method of diversion scheme are shown by an example of construction diversion scheme optimization with the discharge control condition of upstream hydropower station. The study is valuable for establishment and optimization of construction diversion scheme with upstream reservoir discharge control.
摘要The so-called construction scheme optimization is to adjust the original good construction scheme, such as eliminating hidden dangers, simplifying the structure, reducing the cost, etc., thus simplifying the original scheme and reducing the construction cost. Because the construction plan is different, the construction period will be different and the machines and tools required will be different, thus the expenses incurred will also be different. Therefore, the on-site technical engineer should put forward a technically advanced, technically reasonable and organizationally capable construction plan based on the contract period, taking into account factors such as the scale, nature, complexity, site conditions, equipment conditions and personnel quality of the project, and strive to reduce the project cost. In this paper, from the aspects of the determination of construction methods, the selection of construction machines and tools, the arrangement of construction sequence and the organization and arrangement of construction, the application of the optimization method of construction scheme in the cost management of engineering projects, such as the formulation of advanced, economical and reasonable construction scheme, the rational selection of machinery and the full play of the efficiency of machinery, is analyzed, and the importance of construction scheme in the cost management of projects is expounded.
基金the financial support by the National Key Research and Development Program of China(Grant No.2020YFC1808102)the Natural Science Foundation of China(No.51874328 and No.52074311)。
摘要Optimization of fracturing perforation is of great importance to the commingling gas production in coal measure strata.In this paper,a 3 D lattice algorithm hydraulic fracturing simulator was employed to study the effects of perforation position and length on hydraulic fracture propagation in coal measures of the Lin-Xing block,China.Based on field data,three lithologic combinations are simulated:1)a thick section of coal seam sandwiched by sandstones;2)a thin coal seam layer overlay by gas-bearing tight sandstone;3)two coal seams separated by a thin layer of sandstone.Our simulation shows that perforation position and length in multi-layer reservoirs play a major role in hydraulic fracture propagation.Achieving maximum stimulated volume requires consideration of lithologic sequence,coal seam thickness,stress states,and rock properties.To improve the combined gas production in coal measure strata,it is possible to simultaneously stimulate multiple coal seams or adjacent gas-bearing sandstones.In these cases,perforation location and length also significantly impact fracture propagation,and therefore should be carefully designed.Our simulation results using 3 D lattice algorithm are qualitatively consistent with laboratory physical simulation.3 D lattice models can be used to effectively simulate the fracture propagation through layers in coal measure strata.The numerical results provide guidance for perforation optimization in the hydraulic fracturing of coal measure strata.
基金Supported by the National Natural Science Foundation of China under Grant No. 10902083the Natural Science Foundation of Shannxi Province under Grant No. 2009GM1007
摘要Recently, Xiu et al. [Commun. Theor. Phys. 49 (2008) 905] proposed two schemes of teleporting an N particle arbitrary and unknown state when N groups of three particle general W states are utilized a.s quantum channels. They gave the maximal probability of successful teleportation. Here we find that their operation is not the optimal and the successful probability of the teleportation is not maximum. Moreover, we give the optimal schemes operation and obtain maximal successful probability for teleportation.
摘要China's Rural Cooperative Medical System collapsed alongside communal farming at the end of the Maoist period in 1976, leaving most farmers vulnerable[1]. In rural areas, where 80% of people have been without health insurance of any kind, illness has emerged as a leading cause of poverty[24]. To address the poor state of health care among the rural population, in 2003 the Chinese government launched the New Rural Cooperative Medical System (NCMS),
摘要In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separation spring-driven opening scheme is proposed to achieve rapid and reliable opening of the front cover.The mathematical model of the opening process of the front cover is established by the rigid body dynamics theory.To establish a response surface model to optimize the opening scheme,three main influencing factors of the opening process are obtained through the designed experiments,including the pre-compression,the stiffness of the thrust spring,and the thrust spring force arm length.In addition,the prescribed kinematic law was taken as constraint,and the smaller thrust spring preliminary pressure and angular velocity was taken as optimization expectations.The results show that the opening scheme meets the design requirements on opening process well.It also shows that the optimized scheme can reduce the kinetic energy of the front cover,and the impact on the canister effectively,achieving a reliable and rapid opening of the front cover.
基金The authors would like to acknowledge the funding support of the National Natural Science Foundation of China (Nos. 50579009, 70425001 ) the National 10th Five Year Scientific Project of China for Tackling the Key Problems (2004BA608B-02-02)the Excellence Youth Teacher Sustentation Fund Program of the Ministry of Education of China (Department of Education and Personnel [ 2002 ] 350).
摘要The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of importance in both theory and practice in water resource systems engineering. In order to achieve consistency and eliminate the dimensions of fuzzy qualitative and fuzzy quantitative evaluation indexes, to determine the weights of the indexes objectively, and to increase the differences among the comprehensive evaluation index values of water transportation project schemes, a projection pursuit method, named FPRM-PP for short, was developed in this work for selecting the optimal water transportation project scheme based on the fuzzy preference relation matrix. The research results show that FPRM-PP is intuitive and practical, the correction range of the fuzzy rained is both stable and accurate; preference relation matrix A it produces is relatively small, and the result obtherefore FPRM-PP can be widely used in the optimal selection of different multi-factor decision-making schemes.
基金Project supported by the National Natural Science Foundation of China(No.11671106)the Fundamental Research Funds for the Central Universities(No.2016MS33)
摘要This study develops an optimized finite difference iterative (OFDI) scheme for the two-dimensional (2D) viscoelastic wave equation. The OFDI scheme is obtained using a proper orthogonal decomposition (POD) method. It has sufficiently high accuracy with very few unknowns for the 2D viscoelastic wave equation. Existence, stability, and convergence of the OFDI solutions are analyzed. Numerical simulations verify efficiency and feasibility of the proposed scheme.
摘要Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categorize the correlation extent of compared sequences and a certain reference sequence in a system with uncertain information. It is applied to evaluating and selecting AC cold/heat sources from four main aspects, which are technology, economy, reliability, and operation and management. Case study shows that the result for selecting AC cold/heat sources with the GRA method can be more reasonable and convincible. Thus it offers a new approach for designers in heating, ventilating and air conditioning field to compare and evaluate different AC cold/heat sou rces.
摘要In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, through computer simulation experiment were analyzed, and optimization design, through the real car collision test, make the concrete guardrail after heightening structure satisfies the requirement of the safety performance of current specification. The results show that the protective performance of the two guardrail schemes meets the requirements of the current guardrail evaluation standards through the computer simulation experiment. Through the optimized design of scheme 1, the actual car crash test proves that the enhanced structure of Minhua TYPE II concrete guardrail can meet the requirements of safety performance evaluation. The research results provide an important basis for the transformation of the guardrail and the revision of the current design of expressway in China.
摘要The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicability and reliability of upward recursive formula in principle is amended.An optimal scheme of upward-and downward-joint recursions has been developed for the sequential F(z) computations.No additional accuracy is needed with the fundamental term of recursion because the absolute error of Fn(z) always decreases with the recursive approach.The scheme can be employed in modifying any of existent subprograms for Fn computations.In the case of p-d-f-and g-type Gaussians,combining this method with Schaad's formulas can reduce,at least,the additive operations by a factor 40%;the multiplicative and exponential operations by a factor 60%.
摘要AT the present stage, the urban traffic system facing the problem of road congestion is becoming more serious in this background, the need to improve the existing urban traffic problems, set scientific traffic planning scheme with the help of micro traffic engineering technology, cooperate with micro traffic simulation technology to complete the problem of traffic congestion. This paper takes the above content as the core, analyzes the actual cases and scientifically verifies the simulation research results combined with the actual project, and finally explains the specific application of micro-traffic engineering technology in urban traffic engineering improvement in detail.