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家兔的合成配套系建系法及配套系 被引量:2
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作者 谷子林 《中国养兔杂志》 1998年第3期4-5,共2页
在家兔的育种过程中,品系繁育是重要的繁育方式。通常品系繁育有三种方法:系祖建系法、群体建系法(群体继代选育建系法)和合成配套系建系法。后者又称专门化品系建系法。这种育种方式是将家兔的全部选育性状划分为几个“性状组”,... 在家兔的育种过程中,品系繁育是重要的繁育方式。通常品系繁育有三种方法:系祖建系法、群体建系法(群体继代选育建系法)和合成配套系建系法。后者又称专门化品系建系法。这种育种方式是将家兔的全部选育性状划分为几个“性状组”,然后培育几个品系(通常3~4个,以... 展开更多
关键词 家兔 育种 合成配套 建系法
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浅谈初中数学利用建系法巧解几何题 被引量:1
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作者 曾钰玲 《数理化解题研究》 2021年第20期2-3,共2页
一道数学题,从不同的角度思考,运用不同的数学知识,通常会有不同的解题思路.而初中阶段,以北师大的教材为例,从初二开始研究平面直角坐标系与函数,学生开始有了坐标系的概念,便可以开始给学生灌输建系法解题的思想.
关键词 初中数学 建系法 巧解几何题
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泰山长毛兔的选育
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作者 王景才 王守荣 +2 位作者 李志才 肖允水 邢云芬 《特产研究》 2003年第4期25-27,共3页
根据合成育种原理,利用德系安哥拉兔产毛量高、被毛密度大的遗传基础,导入GSAB兔粗毛率高、生长快、体重大的优良基因,经杂种1代横交或用德系安哥拉兔回交后,分离筛选得到毛密、体大、粗毛含量高的粗毛型兔,然后进一步同质迁入新法系安... 根据合成育种原理,利用德系安哥拉兔产毛量高、被毛密度大的遗传基础,导入GSAB兔粗毛率高、生长快、体重大的优良基因,经杂种1代横交或用德系安哥拉兔回交后,分离筛选得到毛密、体大、粗毛含量高的粗毛型兔,然后进一步同质迁入新法系安哥拉、沪2071系等粗毛型兔的高产基因,获得高产毛量、高粗毛率的理想型个体组建选育核心群。核心群基因来源及血统比例为德系安哥拉占37.5%,GSAB占12.5%,新法系和沪2071系分别占25%。 展开更多
关键词 泰山长毛兔 选育 核心群 转基因 合成育种 多品种杂交合成建系法 基础群
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如何提高小尾寒羊生产性能
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作者 彭秀君 《内蒙古草业》 1996年第3期21-22,共2页
如何提高小尾寒羊生产性能彭秀君(扎赉特旗家畜繁育改良指导站137600)小尾寒羊以其体格大、早熟、生长发育快、多胎高产、产毛量高、四季发情配种、极耐粗饲、适应性强等优点,被称为“国宝”和“世界超级羊”。各地相继引入,... 如何提高小尾寒羊生产性能彭秀君(扎赉特旗家畜繁育改良指导站137600)小尾寒羊以其体格大、早熟、生长发育快、多胎高产、产毛量高、四季发情配种、极耐粗饲、适应性强等优点,被称为“国宝”和“世界超级羊”。各地相继引入,有些地区把发展小尾寒羊列入发展规划... 展开更多
关键词 小尾寒羊 生产性能 繁育 建系法 近交建系法 群体继代选育 利用
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Thesaurus-based approach for building domain ontology with a case study of military aircraft prototype ontology construction 被引量:3
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作者 真溱 唐爱民 +1 位作者 沈钧毅 卢胜军 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期353-356,共4页
To alleviate the amount of work involved in constructing a domain ontology, starting with the base of an existing terminological-rich thesaurus is better than starting from scratch. With a case study of reengineering ... To alleviate the amount of work involved in constructing a domain ontology, starting with the base of an existing terminological-rich thesaurus is better than starting from scratch. With a case study of reengineering the Defense Science and Technology Thesaurus into a prototype military aircraft ontology, a four-phase thesaurus-based methodology is introduced and investigated, which consists of identifying the application purpose, overall design, designing in detail and evaluation. Designing in detail is the core step, converting the terms and semantic relationships of the thesaurus into an ontology and supplementing richer semantic relationships. The resulting prototype ontology includes 87 concepts and 34 relationships, and can be extended and scaled up to a full-fledged domain ontology in the future. Eight universal genres of relationships of this ontology are preliminarily summarized and analyzed, including equivalent relationships, approximate relationships, generic/abstract relationships, part/whole relationships, cause/effect relationships, entity/location relationships etc., and the normalization of semantic relationships is critical to the merging and reusing of follow-up multiple ontologies. 展开更多
关键词 THESAURUS domain ontology CONSTRUCTION METHODOLOGY semantic relationship
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Analysis and Modeling of the Central Air-Conditioning System in Intelligent Buildings 被引量:6
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作者 郭巧 徐庆伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期295-297,共3页
The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed ... The central air conditioning system in an intelligent building (IB) was analyzed and modeled in order to perform the optimization scheduling strategy of the central air conditioning system. A set of models proposed and a type of periodically autoregressive model (PAR) based on the improved genetic algorithms (IGA) were used to perform the optimum energy saving scheduling. The example of the Liangmahe Plaza was taken to show the effectiveness of the methods. 展开更多
关键词 intelligent building analysis and modeling central air conditioning energy saving
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对“直线与平面所成角”复习的教学思考
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作者 曹贤鸣 陈亚菲 《中学数学研究(华南师范大学)(下半月)》 2022年第1期21-23,共3页
复习“直线与平面所成角”的求解方法时,在巩固向量建系法和等体积法之后,还要回归到综合几何法的复习.本文通过具体实例,介绍了利用“垂面法”这一传统的综合几何的方法求解直线与平面所成角,通过对学生几何法的训练,完善学生求解直线... 复习“直线与平面所成角”的求解方法时,在巩固向量建系法和等体积法之后,还要回归到综合几何法的复习.本文通过具体实例,介绍了利用“垂面法”这一传统的综合几何的方法求解直线与平面所成角,通过对学生几何法的训练,完善学生求解直线与平面所成角的方法,帮助学生完善立体几何中点、线、面之间的知识体系和方法体系. 展开更多
关键词 直线与平面所成角 向量建系法 等体积 综合几何 教学实践
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一道中考真题的多角度解法探究
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作者 沈建新 《数理化学习(初中版)》 2024年第6期28-31,共4页
一题多解是指从不同角度,运用不同的思维方式来解答同一道题的思考方法.一题可破万题山,经常进行一题多解的训练,可以锻炼学生的思维,使头脑更灵活.在进行一题多解的练习时,要根据题目的具体情况,首先确定思维的起点,然后沿着不同的思... 一题多解是指从不同角度,运用不同的思维方式来解答同一道题的思考方法.一题可破万题山,经常进行一题多解的训练,可以锻炼学生的思维,使头脑更灵活.在进行一题多解的练习时,要根据题目的具体情况,首先确定思维的起点,然后沿着不同的思考方向,就能找到不同的解题方法.本文以一道中考题为例进行阐释. 展开更多
关键词 构造模型 一题多解 辅助圆 建系法
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Modeling approaches to pressure balance dynamic system in shield tunneling 被引量:2
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作者 李守巨 于申 屈福政 《Journal of Central South University》 SCIE EI CAS 2014年第3期1206-1216,共11页
In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial n... In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial neural network(ANN) and input-output data of the system during shield tunneling and can overcome the precision problem in mechanistic modeling(MM) approach. The computational results show that the training algorithm with Gauss-Newton optimization has fast convergent speed. The experimental investigation indicates that, compared with mechanistic modeling approach, intelligent modeling procedure can obviously increase the precision in both soil pressure fitting and forecasting period. The effectiveness and accuracy of proposed intelligent modeling procedure are verified in laboratory tests. 展开更多
关键词 intelligent modeling neural network pressure balance system excavation chamber analytically modeling approach
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Thermal-hydraulic modeling and analysis of hydraulic system by pseudo-bond graph 被引量:3
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作者 胡均平 李科军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2578-2585,共8页
To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they ... To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they can be separated into two categories: capacitive components and resistive components. Then, the thermal-hydraulic pseudo-bond graphs of capacitive C element and resistance R element were developed, based on the conservation of mass and energy. Subsequently, the connection rule for the pseudo-bond graph elements and the method to construct the complete thermal-hydraulic system model were proposed. On the basis of heat transfer analysis of a typical hydraulic circuit containing a piston pump, the lumped parameter mathematical model of the system was given. The good agreement between the simulation results and experimental data demonstrates the validity of the modeling method. 展开更多
关键词 thermodynamics hydraulic system pseudo-bond graph piston pump modeling temperature simulation
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Le Corbusier and a New Structural System as the Germ of the Modern Grammar 被引量:2
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作者 Ana Maria Rigotti 《Journal of Civil Engineering and Architecture》 2017年第7期677-690,共14页
The opposition between the terms carcasse (carcass), conceptualized by Auguste Perret, and ossature (frame), proposed as an alternative by Le Corbusier, gives rise to the exploration of the capital contribution of... The opposition between the terms carcasse (carcass), conceptualized by Auguste Perret, and ossature (frame), proposed as an alternative by Le Corbusier, gives rise to the exploration of the capital contribution of the "Dom-ino" prototype as the basic and in escapable condition for an aesthetic operation. Some issues addressed are: the importance of the question of the structure--which remains implicit in Toward an Architecture--as key to a quest for the specificity of architecture; Le Corbusier's troublesome relationship with Perret and the debates between them, which convey two different ways of understanding the potential contributions of concrete to the redefinition of architectural vocabulary; the "Dom-ino" system considered as a new structural type in the sense ascribed to this category by Violletle Duc; the topic of the abri souverain (sovereign shelter) fit for all programs, which triggered typological invention; the ways in which Le Corbusier plays with Gottfried Semper's Urformen and, finally, how this new structural type anchors Le Corbusier's radical redefinition of the elements of the discipline, the making of a new grammar. 展开更多
关键词 Structure modern architecture CONCRETE structural type architectural vocabulary.
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Modeling and Implementing ISO 13584-based Part Library
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作者 杨东 肖丽雯 +1 位作者 何援军 张申生 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期73-77,共5页
ISO 13584 (i.e. PLIB) is an international standard for the representation and exchange of CAD part libraries. It aims to provide an application-independent mechanism to enable the share of part library information bet... ISO 13584 (i.e. PLIB) is an international standard for the representation and exchange of CAD part libraries. It aims to provide an application-independent mechanism to enable the share of part library information between applications. In this paper, the approach of modeling part library conforming to ISO 13584 is presented. Also, a prototype of part library management system, i.e. BYL-PLIB, whose implementation is in agreement with ISO 13854 is developed to demonstrate the usefulness of proposed approach. 展开更多
关键词 Part Library ISO 13584 STEP
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UML statechart based rigorous modeling of real-time system
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作者 赖明志 尤晋元 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期74-80,共7页
Rigorous modeling could ensure correctness and could verify a reduced cost in embedded real-time system development for models. Software methods are needed for rigorous modeling of embedded real-time systems. PVS is a... Rigorous modeling could ensure correctness and could verify a reduced cost in embedded real-time system development for models. Software methods are needed for rigorous modeling of embedded real-time systems. PVS is a formal method with precise syntax and semantics defined. System modeled by PVS specification could be verified by tools. Combining the widely used UML with PVS, this paper provides a novel modeling and verification approach for embedded real-time systems. In this approach, we provide 1) a time-extended UML statechart for modeling dynamic behavior of an embedded real-time system; 2) an approach to capture timed automata based semantics from a timed statechart; and 3) an algorithm to generate a finite state model expressed in PVS specification for model checking. The benefits of our approach include flexibility and user friendliness in modeling, extendability in formalization and verification content, and better performance. Time constraints are modeled and verified and is a highlight of this paper. 展开更多
关键词 embedded real-time system UML statechart PVS timed automata model checking
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Treatment of Peptic Ulcer with Xiao Jianzhong Tang—A Report of 80 Cases
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作者 周光前 王薇 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2005年第1期23-24, ,共2页
With Xiao Jianzhong Tang (小建中汤), the author has successfully treated 80 cases of peptic ulcer. The therapeutic effects obtained were compared with that of the Western medicine. A report follows.
关键词 PHYTOTHERAPY ADULT Drugs Chinese Herbal Duodenal Ulcer FEMALE Humans Male Middle Aged Peptic Ulcer Stomach Ulcer
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Soft Sensor Model Derived from Wiener Model Structure: Modeling and Identification 被引量:2
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作者 曹鹏飞 罗雄麟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第5期538-548,共11页
The processes of building dynamic and static relationships between secondary and primary variables are usually integrated in most of nonlinear dynamic soft sensor models. However, such integration limits the estimatio... The processes of building dynamic and static relationships between secondary and primary variables are usually integrated in most of nonlinear dynamic soft sensor models. However, such integration limits the estimation accuracy of soft sensor models. Wiener model effectively describes dynamic and static characteristics of a system with the structure of dynamic and static submodels in cascade. We propose a soft sensor model derived from Wiener model structure, which is an extension of Wiener model. Dynamic and static relationships between secondary and primary variables are built respectively to describe the dynamic and static characteristics of system. The feasibility of this model is verified. Then the expression of discrete model is derived for soft sensor system. Conjugate gradient algorithm is applied to identify the dynamic and static model parameters alternately. Corresponding update method for soft sensor system is also given. Case studies confirm the effectiveness of the proposed model, alternate identification algorithm, and update method. 展开更多
关键词 soft sensor Wiener model MODELING alternate identification
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Modeling, identification and compensation for geometric errors of laser annealing table 被引量:1
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作者 李殿新 张建富 +1 位作者 张云亮 冯平法 《Journal of Central South University》 SCIE EI CAS 2014年第3期904-911,共8页
In order to improve the process precision of an XY laser annealing table, a geometric error modeling, and an identification and compensation method were proposed. Based on multi-body system theory, a geometric error m... In order to improve the process precision of an XY laser annealing table, a geometric error modeling, and an identification and compensation method were proposed. Based on multi-body system theory, a geometric error model for the laser annealing table was established. It supports the identification of 7 geometric errors affecting the annealing accuracy. An original identification method was presented to recognize these geometric errors. Positioning errors of 5 lines in the workspace were measured by a laser interferometer, and the 7 geometric errors were identified by the proposed algorithm. Finally, a software-based error compensation method was adopted, and a compensation mechanism was developed in a postprocessor based on LabVIEW. The identified geometric errors can be compensated by converting ideal NC codes to actual NC codes. A validation experiment has been conducted on the laser annealing table, and the results indicate that positioning errors of two validation lines decreased from ±37 μm and ±33 μm to ±5 μm and ±4.5 μm, respectively. The geometric error modeling, identification and compensation method presented in this work can be straightforwardly extended to any configurations of 2-dimensional worktable. 展开更多
关键词 geometric error error modeling error measurement error identification error compensation laser annealing table
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Multi-objective modeling and optimization for scheduling of cracking furnace systems 被引量:8
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作者 Peng Jiang Wenli Du 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第8期992-999,共8页
Cracking furnace is the core device for ethylene production. In practice, multiple ethylene furnaces are usually run in parallel. The scheduling of the entire cracking furnace system has great significance when multip... Cracking furnace is the core device for ethylene production. In practice, multiple ethylene furnaces are usually run in parallel. The scheduling of the entire cracking furnace system has great significance when multiple feeds are simultaneously processed in multiple cracking furnaces with the changing of operating cost and yield of product. In this paper, given the requirements of both profit and energy saving in actual production process, a multi-objective optimization model contains two objectives, maximizing the average benefits and minimizing the average coking amount was proposed. The model can be abstracted as a multi-objective mixed integer non- linear programming problem. Considering the mixed integer decision variables of this multi-objective problem, an improved hybrid encoding non-dominated sorting genetic algorithm with mixed discrete variables (MDNSGA-II) is used to solve the Pareto optimal front of this model, the algorithm adopted crossover and muta- tion strategy with multi-operators, which overcomes the deficiency that normal genetic algorithm cannot handle the optimization problem with mixed variables. Finally, using an ethylene plant with multiple cracking furnaces as an example to illustrate the effectiveness of the scheduling results by comparing the optimization results of multi-objective and single objective model. 展开更多
关键词 Cracking furnace systems Feed scheduling Multi-objective mixed integer nonlinear optimization Genetic algorithm
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Strategic Focus and Business Model Organization: The Mean Field Analysis Approach
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作者 Paola Pisano Daniele Manini +1 位作者 Marco Gribaudo Marco Pironti 《Journal of Modern Accounting and Auditing》 2011年第7期709-718,共10页
The objective of this research is to show a new methodology for modeling phenomena present in complex economic systems. The case study we analyzed is the adoption of open organization model among firms operating in a ... The objective of this research is to show a new methodology for modeling phenomena present in complex economic systems. The case study we analyzed is the adoption of open organization model among firms operating in a particular industry. A firm with an open system model creates and captures value taking advantage not only from the internal resource but also from external. The organization could approach to open model acquisition using different focus: external focus namely looking out of its boundary, acting and reacting to competitor innovation, costumers' changing, demand growth, or internal focus remaining inside its boundary improving its best capabilities ignoring what happened outside (Vagnani, Moran, & Simoni, 2010). The actors involved are firms, customers and suppliers linked together through a business to business model. The methodology is based on an Object-Oriented Analysis Field Model that allows to intuitively describe systems characterized by a large number of objects that interact, as in this case of a system composed by different organizational entities. The system simulation allows to analyze how the actors influence the acquisition and diffusion of the open organization model. This approach permits the generation of different classes of objects to represent all actors involved in the evolution of the system and to define the dynamics that determine their interaction. The solution of the model can be approximated using the Mean-Field analysis technique (Kurtz, 1978), following the results proposed in Bobbio, Gribaudo, and Yelek (2008). A qualitative result is illustrated in order to show the applicability of the proposed methodology and to emphasize its relevant features: flexible modeling approach, capacity of solving complex systems and output management facilities. The presented model is comprehensive and its scope is wide; it could be used to study the behavior of enterprises changing model in many different scenarios and situations. In future works quantitative results will be given, and different situations will be analyzed. 展开更多
关键词 DIFFUSION open organization model internal focus external focus mean field analysis
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The Innovations and Shortages of the New Budget Law
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《International English Education Research》 2015年第4期8-9,共2页
The introduction of the new budget law is one of the most important achievements of the construction of national legal system. It is a landmark event in building financial system. The new budget law has made a lot of ... The introduction of the new budget law is one of the most important achievements of the construction of national legal system. It is a landmark event in building financial system. The new budget law has made a lot of breakthroughs and innovations in the budget managemenL to lead direction for further deepen fiscal reform. However, the modification of the budget law can only adopt the principle of limited modification, there are still many problems. This paper discusses the innovation and deficiency of the new budget law under the background of budget law modification, and makes suggestions to further improve the budget law. 展开更多
关键词 new budget law INNOVATION SHORTAGE improve.
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Multi-criteria Decision of Type and Building Material for Simple House Construction
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作者 Wahyu Wuryanti 《Journal of Civil Engineering and Architecture》 2013年第4期433-439,共7页
Facing the innovation technology in building construction, the designer has the option in selecting the type of system construction and building materials. There is a big question for the designer and owner on how to ... Facing the innovation technology in building construction, the designer has the option in selecting the type of system construction and building materials. There is a big question for the designer and owner on how to evaluate the quality material to meet the technical requirements as building construction reliability. By demand to provide a low cost house, there is need for improving structure model and material construction for residents. When material cost takes 60%-70% of total construction cost, it is important to select the appropriate building material. Currently the innovation of material building for main frame and wall component has present for residential projects in Indonesia. Attempt to replace the traditional material such as brick or pozzolan lime concrete block is developed a new material include utilization of coal combustion waste for concrete block, lightweight concrete, or prefab panel wall. This paper presents the research result to develop a tool support for material and system construction selecting that facilitates the selection an optimal material for a simple house construction. A multi-criteria decision method is used based on performance criteria such as economy, reliability, comfort and eco-friend. 展开更多
关键词 Multi-criteria decision building material simple house.
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