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精打细算价值工程在YL25轮胎压路机设计开发中的应用
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作者 梁建平 刘金山 《交通世界》 2001年第6期46-47,共2页
价值工程是一门技术与经济相结合的新兴学科,既是一种管理技术,又是一种思想方法,其实质就是在可靠地实现使用者所需功能的前提下,努力寻求寿命周期成本最低的实施方法,以达到合理而有效地利用资源。其应用范围广阔,对一个产品而言,产... 价值工程是一门技术与经济相结合的新兴学科,既是一种管理技术,又是一种思想方法,其实质就是在可靠地实现使用者所需功能的前提下,努力寻求寿命周期成本最低的实施方法,以达到合理而有效地利用资源。其应用范围广阔,对一个产品而言,产品成本的70—80%是在产品设计阶段就已经决定。因此,在产品开发过程中应用价值工程,就可以消除对用户毫无意义而又增加制造和使用成本的功能,既满足用户,又能为企业获取利润。 展开更多
关键词 轮胎压路机 算价 值工程 设计开发 操纵系统 碾压 功能区 洒水系统 制动装置 钳盘
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关于中心原子价层电子对数的求算方法 被引量:2
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作者 徐守兵 《化学教学》 CAS 北大核心 2013年第7期64-67,共4页
结合教学实践,归纳总结了求算中心原子价电子对数的常用方法和相关公式的来龙去脉,提出了从配位原子对中心原子的贡献角度求算价层电子对数的新方法,并归纳出易于记忆该新方法的口诀,有助于实施有效教学。
关键词 层电子对 互斥理论 中心原子 层电子对数 层电子对数的求
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流计 电力市场 输电电
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洗扫车高压水系统清洗能力的评价与计算 被引量:3
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作者 肖庆麟 覃先云 《建设机械技术与管理》 2018年第1期54-57,共4页
针对洗扫车行车作业的特点创新性地提出了利用喷嘴打击力、喷杆单位面积打击能量和喷杆单位面积清洗水量这三个参数综合评价洗扫车高压水系统的清洗能力。以某典型洗扫车为例,详细介绍了如何获得以上三个评价参数的计算方法。对清洗喷... 针对洗扫车行车作业的特点创新性地提出了利用喷嘴打击力、喷杆单位面积打击能量和喷杆单位面积清洗水量这三个参数综合评价洗扫车高压水系统的清洗能力。以某典型洗扫车为例,详细介绍了如何获得以上三个评价参数的计算方法。对清洗喷杆的四种喷嘴布置方案的清洗能力进行对比分析表明,侧喷杆能力明显大于中喷杆,其能力是中喷杆的1.8~2.4倍;将侧喷杆的喷嘴型号由原来的A型更改为B型,使喷杆之间清洗能力差值明显降低,有利于提高路面整体清洗效果。试验测试结果进一步验证了本文方法的正确性。 展开更多
关键词 洗扫车 高压水系统 清洗能力 与计
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Excel在房屋定价中的应用
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作者 张春明 《经济研究导刊》 2011年第27期157-158,共2页
商品房的定价被很多人认为很神秘,目前开发商的定价方法无非三类:需求定价、竞争定价和可比楼盘量化定价法。采用实例的方式,通过A楼盘利用可比楼盘量化定价法来为楼盘设定均价。然后利用Excel的简单公式,以及再确定层加价的前提下,来... 商品房的定价被很多人认为很神秘,目前开发商的定价方法无非三类:需求定价、竞争定价和可比楼盘量化定价法。采用实例的方式,通过A楼盘利用可比楼盘量化定价法来为楼盘设定均价。然后利用Excel的简单公式,以及再确定层加价的前提下,来实现整个楼盘的定价。 展开更多
关键词 可比楼盘量化定 Excel算价 权值
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经典价键理论的从头算计算方法 被引量:2
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作者 苏培峰 吴玮 《化学进展》 SCIE CAS CSCD 北大核心 2012年第6期1001-1007,共7页
价键理论是两大现代化学键理论之一,广泛应用于化学键本质和化学反应机理的研究。由于计算困难,价键理论应用局限于定性的讨论而无法有效地开展从头计算研究。现代经典价键理论在经典价键理论的理论基础上,引入合理有效的计算方法,提高... 价键理论是两大现代化学键理论之一,广泛应用于化学键本质和化学反应机理的研究。由于计算困难,价键理论应用局限于定性的讨论而无法有效地开展从头计算研究。现代经典价键理论在经典价键理论的理论基础上,引入合理有效的计算方法,提高了价键计算的效率。本文回顾近年来经典价键理论从头算方法在提高计算精度和拓展研究范围方面的发展,并简要展望价键理论方法的发展趋势。 展开更多
关键词 从头算价 方法发展 复杂体系
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房地产评估中三种评估方法的比较研究 被引量:2
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作者 魏静 《河北广播电视大学学报》 2001年第3期46-48,共3页
成本法、收益法、市场比较法是房地产评估的三种方法。三种方法在理论依据、估算方式、适用范围及限制条件上的差异分析;三种方法理论统一性和实践差异性分析;评估方法的选取及评估方法可靠性的实证分析。结论是评估者必须把握市场,... 成本法、收益法、市场比较法是房地产评估的三种方法。三种方法在理论依据、估算方式、适用范围及限制条件上的差异分析;三种方法理论统一性和实践差异性分析;评估方法的选取及评估方法可靠性的实证分析。结论是评估者必须把握市场,准确判断,市场是检验标准;而且评估是科学、经验、艺术的结合。 展开更多
关键词 算价 收益 比准 市场平衡
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Lake Eutrophic Evaluation Based on Bee Immune Evolutionary Algorithm 被引量:1
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作者 党媛 李祚泳 邹艳玲 《Agricultural Science & Technology》 CAS 2010年第4期156-158,188,共4页
In order to establish the lake eutrophic evaluation model for multiple indices,based on the gauge transformation,an index formula in the form of a logarithmic power function was proposed to design an eutrophic evaluat... In order to establish the lake eutrophic evaluation model for multiple indices,based on the gauge transformation,an index formula in the form of a logarithmic power function was proposed to design an eutrophic evaluation model for the " normalized values" of multi-indexes.The parameters in the formula were also optimized by bee immune evolutionary algorithm(BEIEA).The universal index formula was suitable to multiindices items for eutrophic evaluation.At the same time,the formula was applied to practical eutrophic evaluations in 10 regions of Dong Lake.The evaluation results were coincident with those obtained from the power function of weighted sums and also with actual conditions.It was shown that the bee immune evolutionary algorithm was suitable to the parameter optimization in the eutrophic evaluation model. 展开更多
关键词 LAKE Eutrophic evaluation Bee algorithm Bee immune evolutionary algorithm Parameter optimization
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Application Comparison of Association Rules and C4.5 Rules in Land Evaluation 被引量:3
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作者 李亭 杨敬锋 陈志民 《Agricultural Science & Technology》 CAS 2010年第4期144-147,共4页
Association rules and C4.5 rules can overcome the shortage of the traditional land evaluation methods and improve the intelligibility and efficiency of the land evaluation knowledge.In order to compare these two kinds... Association rules and C4.5 rules can overcome the shortage of the traditional land evaluation methods and improve the intelligibility and efficiency of the land evaluation knowledge.In order to compare these two kinds of classification rules in the application,two fuzzy classifiers were established by combining with fuzzy decision algorithm especially based on Second General Soil Survey of Guangdong Province.The results of experiments demonstrated that the fuzzy classifier based on association rules obtain a higher accuracy rate,but with more complex calculation process and more computational overhead;the fuzzy classifier based on C4.5 rules obtain a slightly lower accuracy,but with fast computation and simpler calculation. 展开更多
关键词 Land evaluation Association rules C4.5 Algorithm Fuzzy decision
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不能去掉“三个字”
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《探索与求是》 1999年第3期43-43,共1页
关键词 发电报 营业员 小姐 英国人 算价 妻子 现身 瑞士 字数 电文
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Land Evaluation Method Based on Decision Tree Produced by C4.5 and Fuzzy Decision 被引量:2
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作者 杨敬锋 李亭 陈志民 《Agricultural Science & Technology》 CAS 2010年第3期1-3,27,共4页
[Objective]The aim was to overcome the shortage of being difficult to build land evaluation model when the impact factors had continuous value in the traditional land evaluation process,as well as to improve the intel... [Objective]The aim was to overcome the shortage of being difficult to build land evaluation model when the impact factors had continuous value in the traditional land evaluation process,as well as to improve the intelligibility of the land evaluation knowledge.[Method] The land evaluation method combining classification rule extracted by C4.5 algorithm with fuzzy decision was proposed in this study.[Result] The result of Second General Soil Survey of Guangdong Province had demonstrated that the method was convenient to extract classification rules,and by using only 100 rules,quantity correct rate 86.67% and area correct rate 84.80% of land evaluation could be obtained.[Conclusions] The use of C4.5 algorithm to obtain the rules,combined with fuzzy decision algorithm to build classifiers had got satisfactory results,which provided a practical algorithm for the land evaluation. 展开更多
关键词 Land Evaluation C4.5 Algorithm Fuzzy decision
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A New Evaluation Algorithm for the Influence of User in Social Network 被引量:6
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作者 JIANG Wei GAO Mengdi +1 位作者 WANG Xiaoxi WU Xianda 《China Communications》 SCIE CSCD 2016年第2期200-206,共7页
Online social networks have gradually permeated into every aspect of people's life.As a research hotspot in social network, user influence is of theoretical and practical significant for information transmission, ... Online social networks have gradually permeated into every aspect of people's life.As a research hotspot in social network, user influence is of theoretical and practical significant for information transmission, optimization and integration. A prominent application is a viral marketing campaign which aims to use a small number of targeted infl uence users to initiate cascades of infl uence that create a global increase in product adoption. In this paper, we analyze mainly evaluation methods of user infl uence based on IDM evaluation model, Page Rank evaluation model, use behavior model and some other popular influence evaluation models in currently social network. And then, we extract the core idea of these models to build our influence evaluation model from two aspects, relationship and activity. Finally, the proposed approach was validated on real world datasets,and the result of experiments shows that our method is both effective and stable. 展开更多
关键词 social networks INFLUENCE opinionleaders
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Estimation of the Economic Value of Irrigation Water in Jordan 被引量:1
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《Journal of Agricultural Science and Technology(B)》 2012年第5期487-497,共11页
Insight into the different values of water is essential to support rational decision making about policies, management and investments in the water sector. The main objective of this paper is to estimate an economic v... Insight into the different values of water is essential to support rational decision making about policies, management and investments in the water sector. The main objective of this paper is to estimate an economic value of irrigation water in Jordan by choosing appropriate methodology fit with available data. The Residual Imputation Method (RIM) is used to determine the average economic value of irrigation water used in agriculture across crops. The results showed that the weighted average of water value used in field crops is JD 0.44 m"3 and JD 1.23 m3 for vegetable crops and JD 0.23 m3 for fruit trees. The overall weighted average water value in irrigation is estimated with JD 0.51 m"3. With regard to individual crops, cucumbers had the highest water values with about JD 6.05 m3, followed by string beans with JD 2.64 m3, and sweet pepper with JD 2.54 m3. The lowest returns per m3 were provided by squash, radish and hot pepper. For fruit tress banana has the highest water value JD 0.79 m3 and olive tress has the lowest with only JD 0.069 m3. The current practice of some banana producers is economically rational by installing Reverse Osmosis unit to irrigate banana, since water value is twice the desalination costs of one cubic meter. The estimated values represent the maximum price that farmers might be willing to pay for water under the current market conditions. Water subsidy distorts farmers' perception of water as a scarce and thus valuable resource. Low water prices are thus likely to engender excessive use. It is necessary to allow water prices to recover the real cost of water supply and to ensure financial sustainability of water utilities. 展开更多
关键词 Economic value residual imputation irrigation water horticultural crops.
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Eco-compensation of Wetlands in Yellow River Delta of Shandong Province,China 被引量:3
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作者 HAN Mei CUI Jinlong +2 位作者 HAO Zhen WANG Yi WANG Renqing 《Chinese Geographical Science》 SCIE CSCD 2012年第1期119-126,共8页
Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becom... Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becoming in- creasingly important for policy makers. In this study, remote sensing, field investigations, department visits, and other methods were used to survey wetland types, assess wetland area changes, and calculate wetland economic value. Mar- ket value loss and ecological ftmction value loss, caused by reduction of wetland area and environmental pollution were calculated using commonly accepted methods of market valuation, ecological valuation, environmental protection investment cost analysis, and outcome parameters. According to market value loss and ecological function value loss, preliminarily fund allocation for wetland and ecological compensation was calculated. This will provide an important reference for future Yellow River Delta eco-compensation studies. 展开更多
关键词 Yellow River Delta WETLAND eco-compensation compensation standard
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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Building and Researching the Bidding Model Based on the Costof Power Plant
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作者 秦春申 叶春 赵景峰 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期77-80,共4页
A bidding model of neural network was presented to pursue the largest benefit according to the policy of separating power plants from network and bidding transaction. This model bases on the cost of power plant and it... A bidding model of neural network was presented to pursue the largest benefit according to the policy of separating power plants from network and bidding transaction. This model bases on the cost of power plant and its research object is a power plant in the market. The market clearing price (MCP) can be predicted and an optimized load curve can be decided in this model. The model may provide technical support for the power plant. 展开更多
关键词 power system power market neural network market clearing price
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Reserve estimation of an open pit mine under price uncertainty by real option approach 被引量:8
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作者 AKBARI Afshin Dehkharghani OSANLOO Morteza SHIRAZI Mohsen Akbarpour 《Mining Science and Technology》 EI CAS 2009年第6期709-717,共9页
Reserve estimation is a key to find the correct NPV in a mining project. The most important factor in reserve estimation is the metal price. Metal price fluctuations in recent years were exaggerated, and imposed a hig... Reserve estimation is a key to find the correct NPV in a mining project. The most important factor in reserve estimation is the metal price. Metal price fluctuations in recent years were exaggerated, and imposed a high degree of uncertainty to the reserve estimation, and in consequence to the whole mine planning procedure. Real option approach is an efficient method of decision making in the uncertain conditions. This approach has been used for evaluation of defined natural resources projects until now. This study considering the metal price uncertainty used real option approach to prepare a methodology for reserve estimation in open pit mines. This study was done on a copper cylindrical deposit, but the achieved methodology can be adjusted for all kinds of deposits. This methodology was comprehensively described through the examples in such a manner that can be used by the mine planners. 展开更多
关键词 RESERVE open pit mining metal price uncertainty Real Option Approach (ROA) copper deposit
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CLUSTERING VALIDITY BASED ON THE IMPROVED S_DBW INDEX 被引量:1
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作者 Tong Jianhua Tan Hongzhou 《Journal of Electronics(China)》 2009年第2期258-264,共7页
For many clustering algorithms,it is very important to determine an appropriate number of clusters,which is called cluster validity problem.In this paper,a new clustering validity assessment index is proposed based on... For many clustering algorithms,it is very important to determine an appropriate number of clusters,which is called cluster validity problem.In this paper,a new clustering validity assessment index is proposed based on a novel method to select the margin point between two clusters for in-ter-cluster similarity more accurately,and provides an improved scatter function for intra-cluster similarity.Simulation results show the effectiveness of the proposed index on the data sets under consideration regardless of the choice of a clustering algorithm. 展开更多
关键词 Clustering validity Inter-cluster similarity Intra-cluster similarity
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Calculation of slope-cover height under price fluctuation in open-pit mines 被引量:1
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作者 Ma Jinyan Cai Qingxiang +1 位作者 Liu Fuming Chen Shuzhao 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期293-297,共5页
Leaving ditches between adjacent mining areas can effectively reduce re-stripping in the latter mining area and simultaneously lead to an increment in internal dumping costs in the former mining area. This paper estab... Leaving ditches between adjacent mining areas can effectively reduce re-stripping in the latter mining area and simultaneously lead to an increment in internal dumping costs in the former mining area. This paper establishes calculation models for these two marginal costs. The optimizing model for slope cover height can be determined by including marginal cost models in the objective function. The paper has two main contributions:(a) it fully considers redistribution of dumping space in the model;(b) it introduces price fluctuations and cash discounts in the model. We use the typical open-pit mine as an example to test and prove the model. We conclude that a completely covered slope is reasonable in Haerwusu open pit mine; in addition to an increasing price index, the slope cover height can be reduced; and that price changes are one of the most important influencing factors of slope cover height optimization in an open-pit mine. 展开更多
关键词 Open pit Slope cover height Transport costs Re-stripping
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Construction of Evaluation Index System of Tourism Carrying Capacity of the Jokhang Temple Scenic Spot 被引量:4
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作者 WANG Zhongbin 《Journal of Landscape Research》 2018年第1期90-96,共7页
Based on the in-depth study on the theory of tourism carrying capacity at home and abroad, author of this paper defined the concept and connotation of tourism carrying capacity, and proposed the evaluation index syste... Based on the in-depth study on the theory of tourism carrying capacity at home and abroad, author of this paper defined the concept and connotation of tourism carrying capacity, and proposed the evaluation index system of tourism carrying capacity. He also conducted a systematic analysis of tourism resources in the Jokhang Temple scenic spot, constructed an evaluation index system of tourism carrying capacity of the Jokhang Temple scenic spot, pointed out the status quo of its carrying capacity and factors constraining the carrying capacity through quantitative calculation, and put forward suggestions to regulate its carrying capacity. 展开更多
关键词 Carrying capacity of scenic spots EVALUATION Index system RESEARCH
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