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Probabilistic prediction of expected ground condition and construction time and costs in road tunnels 被引量:4
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作者 A.Mahmoodzadeh S.Zare 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第5期734-745,共12页
Ground condition and construction (excavation and support) time and costs are the key factors in decision-making during planning and design phases of a tunnel project. An innovative methodology for probabilistic est... Ground condition and construction (excavation and support) time and costs are the key factors in decision-making during planning and design phases of a tunnel project. An innovative methodology for probabilistic estimation of ground condition and construction time and costs is proposed, which is an integration of the ground prediction approach based on Markov process, and the time and cost variance analysis based on Monte-Carlo (MC) simulation. The former provides the probabilistic description of ground classification along tunnel alignment according to the geological information revealed from geological profile and boreholes. The latter provides the probabilistic description of the expected construction time and costs for each operation according to the survey feedbacks from experts. Then an engineering application to Hamro tunnel is presented to demonstrate how the ground condition and the construction time and costs are estimated in a probabilistic way. In most items, in order to estimate the data needed for this methodology, a number of questionnaires are distributed among the tunneling experts and finally the mean values of the respondents are applied. These facilitate both the owners and the contractors to be aware of the risk that they should carry before construction, and are useful for both tendering and bidding. 展开更多
关键词 Markov process Geological condition Monte-Carlo (MC) simulation Construction time and costs Hamro tunnel
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SINGLE MACHINE SCHEDULING WITH CONTROLLABLE PROCESSING TIMES AND COMPRESSION COSTS : PROOF OF THEOREMS
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作者 TANGGUOCHUN FOULDS,L.R. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第4期427-436,共10页
Abstract This report is virtually the appendix part of the author's previous paper which includes the proofs for the theorems and lemmas.
关键词 Machine scheduling problems controllable processing times uniform compression time and cost dominance set lateness crash activities polynomial time algorithm
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Weighted Time-Based Global Hierarchical Path Planning in Dynamic Environment 被引量:2
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作者 邢薇薇 魏翔 卢苇 《Transactions of Tianjin University》 EI CAS 2014年第3期223-231,共9页
A weighted time-based global hierarchical path planning method is proposed to obtain the global optimal path from the starting point to the destination with time optimal control. First, the grid-or graph-based modelin... A weighted time-based global hierarchical path planning method is proposed to obtain the global optimal path from the starting point to the destination with time optimal control. First, the grid-or graph-based modeling is performed and the environment is divided into a set of grids or nodes. Then two time-based features of time interval and time cost are presented. The time intervals for each grid are built, during each interval the condition of the grid remains stable, and a time cost of passing through the grid is defined and assigned to each interval. Furthermore, the weight is introduced for taking both time and distance into consideration, and thus a sequence of multiscale paths with total time cost can be achieved. Experimental results show that the proposed method can handle the complex dynamic environment, obtain the global time optimal path and has the potential to be applied to the autonomous robot navigation and traffic environment. 展开更多
关键词 path planning dynamic environment time optimal control time cost
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A Study on Interregional Differences in Elderly Person’s Remote Care in Terms of Traveling Time and Expense:Comparative Consideration in TOKYO Area and OSAKA Area
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作者 Yuichi Sueshige Hideaki Takayanagi Tatsuto Kihara 《Journal of Civil Engineering and Architecture》 2020年第8期433-451,共19页
This study has been carried out to examine the development of an “elderly tele-nursing model” for care provided in-homeby family members and through remote nursing systems in a super-aging society. The time required... This study has been carried out to examine the development of an “elderly tele-nursing model” for care provided in-homeby family members and through remote nursing systems in a super-aging society. The time required for elderly tele-nursing wasinfluenced by whether or not the visitor uses the Shinkansen or the Express train. Based on 40 questionnaires, clear differences wereobserved according to whether visits were “every two weeks” or “once per month”. And finally, comparing the trends andcharacteristics of remote care for the elderly in the TMA (Tokyo Main Area) and Kansai region clarified regional characteristic. 展开更多
关键词 Super-aging society travel time and cost remote elderly care family caregiving interregional differences
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Seem to overrun on time and budget for engineering projects
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作者 CHEN Yu LIANG De Xiang 《International Journal of Technology Management》 2014年第8期177-178,共2页
In this thesis,construction industries face with the major challenges are cost overruns and time delays, which have existed in most of projects, especially in developing countries. Construction projects and the enviro... In this thesis,construction industries face with the major challenges are cost overruns and time delays, which have existed in most of projects, especially in developing countries. Construction projects and the environment are increasingly complex, thus it has greater demands on project managers and cost managers that deliver processes on time. However the process of construction is limited to unforeseeable and variable factors, resulting from many sources. The aim of the report is to analyze determining factors about causing budget overrun and time delays by reviewing and identifying past cases. Furthermore, the construction process is made up of three critical phases, i.e. conception, design, construction. Generally, the majority of time delays and cost overrun happen in the period of construction, where many factors are always unforeseeable, and time delays usually associate with cost overruns. (Chan and Kumaraswamy, 1997) 展开更多
关键词 cost overruns and time delays the construction process case studies client and consultant
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多项目无节奏流水施工时间成本置换优化分析 被引量:1
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作者 王勇胜 梁昌勇 姜利赢 《工程管理学报》 2010年第2期156-159,共4页
无节奏流水施工是施工组织的常见形式。文章考虑了多项目环境下多模式的无节奏流水施工组织,并结合传统的time-cost置换问题进行了建模求解。目标函数直接采用双目标形式,并基于NSGA-Ⅱ非劣排序思想进行了算法设计。仿真测试表明,改进... 无节奏流水施工是施工组织的常见形式。文章考虑了多项目环境下多模式的无节奏流水施工组织,并结合传统的time-cost置换问题进行了建模求解。目标函数直接采用双目标形式,并基于NSGA-Ⅱ非劣排序思想进行了算法设计。仿真测试表明,改进的算法能够有效的获得较优的离散time-cost曲线,可以为复杂环境下的无节奏流水施工组织与实施提供决策支持。 展开更多
关键词 无节奏流水施工 多项目 多模式 time—cost置换 NSGA—Ⅱ
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江西省某三级甲等医院2型糖尿病患者次均住院费用新灰色关联分析 被引量:27
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作者 马强 张彩凤 +2 位作者 李芬 陈玉倩 万晓文 《中国卫生资源》 北大核心 2021年第2期171-175,共5页
目的分析江西省某三级甲等医院2型糖尿病患者次均住院费用的构成以及影响次均住院费用的主要因素,为有效控制此类患者的住院费用及减轻疾病经济负担提供依据。方法选取江西省某三级甲等医院2015—2018年1928例2型糖尿病患者的住院费用明... 目的分析江西省某三级甲等医院2型糖尿病患者次均住院费用的构成以及影响次均住院费用的主要因素,为有效控制此类患者的住院费用及减轻疾病经济负担提供依据。方法选取江西省某三级甲等医院2015—2018年1928例2型糖尿病患者的住院费用明细,利用新灰色关联分析法对患者住院各项费用的关联度、贡献率以及变动率等指标进行分析。结果2015—2018年,次均住院费用的构成比和关联系数最大的影响因素是治疗费,而结构贡献率最高的因素是药品费;与次均住院费用关联度最大的前三项目顺位分别是治疗费(0.9650)、药品费(0.9100)和检查费(0.8125);结构贡献率最高的前三项目顺位是药品费(30.00%)、护理费(11.69%)和诊察费(10.61%),三者累计结构贡献率达到52.30%。结论治疗费、药品费和检查费是影响患者次均住院费用最主要的因素,但服务性项目的收费较低。建议着重控制药品费用的增长,适当减轻检查类项目对费用的影响,严格规范临床路径,合理提高服务性项目费用的比例,进一步体现医护人员的劳务价值,构建糖尿病精细化管理体系,丰富健康管理内涵。 展开更多
关键词 2型糖尿病type 2 diatetes 次均住院费用average hospitalization cost per time 新灰色关联分析new grey relational analysis 结构变动度structural change
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Synchronous hybrid transport network design 被引量:1
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作者 李夏苗 曾明华 +1 位作者 傅白白 朱晓立 《Journal of Central South University》 SCIE EI CAS 2009年第2期332-338,共7页
Delay,as an inevitable real-world phenomenon,is usually ignored in transport network design.A model of urban hybrid transport system with stochastic delay was created on the basis of the idealized public transport sys... Delay,as an inevitable real-world phenomenon,is usually ignored in transport network design.A model of urban hybrid transport system with stochastic delay was created on the basis of the idealized public transport system design.After formulating the total trip time cost composed of accessing time in the sub-region of the city,waiting time at the public transport station,and in-vehicle time in the public transit network,the analytical properties of the total trip time cost function were investigated.The results show that in the urban hybrid transport network design,the total trip time cost reaches its approximate minimum in a δ-neighbourhood of buffer time of 1.5 min,and that through modelling optimal delay in hybrid transport system,the maximal synchronization can be achieved and operational efficiency and passenger satisfaction can be improved.The proposed modelling and analytical investigations are attempts to contribute to more realistic modelling of future idealized public transport system that involves more practical constraints. 展开更多
关键词 transport network design DELAY SYNCHRONIZATION total trip time cost
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Multi-segment and Multi-ply Overlapping Process of Multi Coupled Activities Based on Valid Information Evolution 被引量:1
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作者 WANG Zhiliang WANG Yunxia QIU Shenghai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期176-188,共13页
Complex product development will inevitably face the design planning of the multi-coupled activities, and overlapping these activities could potentially reduce product development time, but there is a risk of the addi... Complex product development will inevitably face the design planning of the multi-coupled activities, and overlapping these activities could potentially reduce product development time, but there is a risk of the additional cost. Although the downstream task information dependence to the upstream task is already considered in the current researches, but the design process overall iteration caused by the information interdependence between activities is hardly discussed; especially the impact on the design process' overall iteration from the valid information accumulation process. Secondly, most studies only focus on the single overlapping process of two activities, rarely take multi-segment and multi-ply overlapping process of multi coupled activities into account; especially the inherent link between product development time and cost which originates from the overlapping process of multi coupled activities. For the purpose of solving the above problems, as to the insufficiency of the accumulated valid information in overlapping process, the function of the valid information evolution (VIE) degree is constructed. Stochastic process theory is used to describe the design information exchange and the valid information accumulation in the overlapping segment, and then the planning models of the single overlapping segment are built. On these bases, by analyzing overlapping processes and overlapping features of multi-coupling activities, multi-segment and multi-ply overlapping planning models are built; by sorting overlapping processes and analyzing the construction of these planning models, two conclusions are obtained: (1) As to multi-segment and multi-ply overlapping of multi coupled activities, the total decrement of the task set development time is the sum of the time decrement caused by basic overlapping segments, and minus the sum of the time increment caused by multiple overlapping segments; (2) the total increment of development cost is the sum of the cost increment caused by all overlapping process. And then, based on overlapping degree analysis of these planning models, by the V1E degree function, the four lemmas theory proofs are represented, and two propositions are finally proved: (1) The multi-ply overlapping of the multi coupled activities will weaken the basic overlapping effect on the development cycle time reduction (2) Overlapping the multi coupled activities will decrease product development cycle, but increase product development cost. And there is trade-off between development time and cost. And so, two methods are given to slacken and eliminate multi-ply overlapping effects. At last, an example about a vehicle upper subsystem design illustrates the application of the proposed models; compared with a sequential execution pattern, the decreasing of development cycle (22%) and the increasing of development cost (3%) show the validity of the method in the example The proposed research not only lays a theoretical foundation for correctly planning complex product development process, but also provides specific and effective operation methods for overlapping multi coupled activities. 展开更多
关键词 multi coupled activities valid information evolution multi-segment multi-ply overlapping development time and cost trade-ofl iteration
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Effect of blockchain technology initiatives on firms’market value 被引量:1
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作者 Haji Suleman Ali Feiyan Jia +1 位作者 Zhiyuan Lou Jingui Xie 《Financial Innovation》 2023年第1期1349-1383,共35页
Despite blockchain’s potential to transform corporations by providing new ways of organizing business processes and handling information,extant research pays inadequate attention to how and under what conditions bloc... Despite blockchain’s potential to transform corporations by providing new ways of organizing business processes and handling information,extant research pays inadequate attention to how and under what conditions blockchain technology provides additional financial value for shareholders.Drawing on the efficient market hypothesis and signaling theory,we examined the relationship between firms’blockchain use,development announcements,and stock market reactions.We used the event study methodology to analyze a sample of blockchain projects initiated by US firms between 2016 and 2019.The sample contains 114 firm-event observations.The findings show that the average abnormal return over a 2 days event period(including the day of the announcement and the day after the announcement)was positive.This positive stock market reaction is even more substantial when firms announce blockchain projects that focus on saving cost or time.Our findings also indicate that blockchain announcements tend to elicit more positive market reactions from smaller firms.We analyzed 249 firm-event observations containing firms from around the world and conclude that blockchain technology has a non-significant long-term impact on operating performance.The contingency approach adopted in our research provides advice for selecting the right mix of blockchain investment initiatives that is most suitable for a given organizational context. 展开更多
关键词 Blockchain Operation efficiency time and cost saving Stock returns Event study
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Full lifetime cost analysis of battery, plug-in hybrid and FCEVs in China in the near future 被引量:2
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作者 Zhihua CAI Xunmin OU +1 位作者 Qian ZHANG Xiliang ZHANG 《Frontiers in Energy》 CSCD 2012年第2期107-111,共5页
This paper analyzes the full lifetime cost of battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and fuel cell electric vehicles (FCEVs) in China in the near future. The full lifetime co... This paper analyzes the full lifetime cost of battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and fuel cell electric vehicles (FCEVs) in China in the near future. The full lifetime cost comprises the initial and periodic cost of owning and operating the vehicle. Compared with the conventional gasoline vehi- cles, the full lifetime cost of the BEVs, PHEVs and FCEVs are approximately 1.5, 0.5 and 2.3 times more in the short term, respectively, due to the higher initial costs and higher non-energy-related costs though the fuel costs are lower. The results also suggest that with reasonably anticipatable technological progress in the long term, the lifetime cost of advanced electric vehicles (EVs) can be close to that of gasoline vehicles. It is found that two aspects of action are most important to make BEVs cost-effective: to support technology improvement to decrease the high cost of BEV and to formulate high energy cost of operating the conventional gasoline car. Moreover, it is important to decrease the non-energy operating costs including regis- tration fee, tax rate and etc., of BEVs at the same time. 展开更多
关键词 electric vehicle (EV) life time cost China
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An EPQ model with variable production,probabilistic deterioration and partial backlogging under inflation 被引量:6
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作者 M.Palanivel R.Uthayakumar 《Journal of Management Analytics》 EI 2014年第3期200-223,共24页
This paper develops an economic production quantity(EPQ)model under the effect of inflation and time value of money.The rate of replenishment is considered to be a variable and the generalized unit production cost fun... This paper develops an economic production quantity(EPQ)model under the effect of inflation and time value of money.The rate of replenishment is considered to be a variable and the generalized unit production cost function is formulated by incorporating several factors,such as raw material,labour,replenishment rate,advertisements and other factors of the manufacturing system.The selling price of a unit is determined by a mark-up over the production cost.We have considered three types of continuous probabilistic deterioration function,and also considered that the holding cost of the item per unit time is assumed to be an increasing linear function of time spent in storage.In addition,shortages are allowed and partially backlogged.This model aids in minimizing the total inventory cost by finding the optimal cycle length and the optimal production quantity.The optimal solution of the model is illustrated with the help of numerical examples. 展开更多
关键词 variable production cost time dependent holding cost probabilistic deterioration partial backlogging INFLATION
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PROJECT REGULARITY: DEVELOPMENT AND EVALUATION OF A NEW PROJECT CHARACTERISTIC 被引量:2
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作者 Jordy Batselier Mario Vanhoucke 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2017年第1期100-120,共21页
The ability to accurately characterize projects novel project characteristic is developed characteristic, called project regularity, is essential to good project management. Therefore, a reflects the value accrue with... The ability to accurately characterize projects novel project characteristic is developed characteristic, called project regularity, is essential to good project management. Therefore, a reflects the value accrue within a project. This expressed in terms of the newly introduced regular/irregular-indicator RI. The widely accepted management system of earned value management (EVM) forms the basis for evaluation of the new characteristic. More concretely, the influence of project regularity on EVMforecasting accuracy is assessed, and is shown to be significant for both time and cost forecasting. Moreover, this effect appears to be stronger than that of the widely used characteristic of project seriality expressed by the serial/parallel-indicator SP. Therefore, project regularity could also be useful as an input parameter for project network generators. Furthermore, the introduction of project regularity can provide project managers with a more accurate indication of the time and cost forecasting accuracy that is to be expected for a certain project and, correspondingly, of how a project should be built up in order to obtain more reliable forecasts during project control. 展开更多
关键词 Project management earned value management time and cost forecasting empirical database Monte Carlo simulation project control system
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Parallelization and Performance Optimization on Face Detection Algorithm with OpenCL: A Case Study 被引量:1
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作者 Weiyan Wang Yunquan Zhang +2 位作者 Shengen Yan Ying Zhang Haipeng Jia 《Tsinghua Science and Technology》 EI CAS 2012年第3期287-295,共9页
Face detect application has a real time need in nature. Although Viola-Jones algorithm can handle it elegantly, today's bigger and bigger high quality images and videos still bring in the new challenge of real time n... Face detect application has a real time need in nature. Although Viola-Jones algorithm can handle it elegantly, today's bigger and bigger high quality images and videos still bring in the new challenge of real time needs. It is a good idea to parallel the Viola-Jones algorithm with OpenCL to achieve high performance across both AMD and NVidia GPU platforms without bringing up new algorithms. This paper presents the bottleneck of this application and discusses how to optimize the face detection step by step from a very naive implementation. Some brilliant tricks and methods like CPU execution time hidden, stubbles usage of local memory as high speed scratchpad and manual cache, and variable granularity were used to improve the performance. Those technologies result in 4-13 times speedup varying with the image size. Furthermore those ideas may throw on some light on the way to parallel applications efficiently with OpenCL. Taking face detection as an example, this paper also summarizes some universal advice on how to optimize OpenCL program, trying to help other applications do better on GPU. 展开更多
关键词 Viola-Jones OPENCL time cost hidden local memory usage parallel granularity
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A supply chain management in a single-vendor and a singlebuyer integrated inventory model with backorders under imperfect production system 被引量:1
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作者 M.Vijayashree R.Uthayakumar 《Journal of Control and Decision》 EI 2017年第4期195-233,共39页
Lead time is an essential factor in any supply chain and inventory management system.In stochastic inventory models,lead time is often viewed as a prescribed constant or a random variable that is not subject to contro... Lead time is an essential factor in any supply chain and inventory management system.In stochastic inventory models,lead time is often viewed as a prescribed constant or a random variable that is not subject to control.In many practical situations,lead times can be controlled by paying additional investment.Using this viewpoint,notion of the crashing cost into stochastic inventory model,in which lead time can be controlled by additional investment.Many researchers have developed various analytical inventory models we have considered the piecewise linear function.So in this proposed model,we derive the mathematical model which is developed by incorporating three types of lead time crashing cost functions(i)exponential function,(ii)polynomial function and(iii)negative exponential function.An integrated inventory model is recognized to find the optimal solutions of order quantity,lead time,total cost for buyer,total cost for vendor and the total number of deliveries from the single-vendor to the single-buyer in one production run.A solution process is suggested for solving the proposed model and numerical examples to illustrate the feature of the proposed model,and examined the effect of the key parameters on the optimal solution and managerial implications are discussed.Numerical examples show that this model offers significant improvements over existing models.A computer code using the software Matlab is developed to derive the optimal solution.The main contribution of this paper is developing a mathematical model and an effective solution procedure to find the optimal solution.Finally,a graphical representation of the computational algorithm is represented by a flowchart in each model. 展开更多
关键词 Integrated inventory model supply chain management lead time crashing cost
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