Based on the characteristics of make-to-order manufacturing, risks in enterprises are analyzed, which are encountered when receiving orders. Dividing the whole process into three stages, this paper provides a qualitat...Based on the characteristics of make-to-order manufacturing, risks in enterprises are analyzed, which are encountered when receiving orders. Dividing the whole process into three stages, this paper provides a qualitative explanation of the risky factors, failure rate, risk level and changes of each stage, and then provides a mathematic model of quantitative analysis by using fuzzy sets and an analytical hierarchy process. In the light of the relationship among the three stages, a formula for calculating risk levels of orders is worked out. Meanwhile, both economic and non-economic losses due to an order failure are considered in the assessment system. An actual case is analyzed using the described method. Suggestions for risk prevention or loss reduction are given.展开更多
Change orders have a significant impact on many aspects of construction projects.They are known to be the primary cause of litigation in the construction industry.Change orders are almost inevitable due to the uniquen...Change orders have a significant impact on many aspects of construction projects.They are known to be the primary cause of litigation in the construction industry.Change orders are almost inevitable due to the uniqueness of each project from many perspectives,such as the type of building,complexity of the design,human factors,and the available resources.Change orders are the formal mechanism to implement design changes during the execution phase.These changes are usually the outcome of lack of visualization by the owner,misunderstanding,miscommunication between different parties involved in the project,shortage in resources,and other factors.This research aims to investigate and rank causes,effects,and control measures of change orders in the construction industry in the U.S.This research presents the results of a questionnaire surveying owners,contractors,and consultants.A total of 123 industry professionals in the Architecture,Engineering,and Construction(AEC)field,with either significant or final decision-making authority on reviewing,issuing,and approving change orders responded to the survey.Results indicated that owners are the primary source followed by consultants and contractors,respectively.Some of the more important control measures identified in this research are collaboration and visualization technologies.展开更多
研究按订单生产(make to order,MTO)模式下随机订单的准入策略.本文提出的准入决策方法分为两步,首先在考虑随机订单的不同属性基础上,采用TOPSIS(technique for order preference by similarity to an ideal solution)方法计算新到订...研究按订单生产(make to order,MTO)模式下随机订单的准入策略.本文提出的准入决策方法分为两步,首先在考虑随机订单的不同属性基础上,采用TOPSIS(technique for order preference by similarity to an ideal solution)方法计算新到订单与理想订单的接近程度,以此作为订单的综合收益,从而对新订单进行分层排序;其次采用MDP(Markov decision process)模型分别计算接受和拒绝订单的期望收益,从而决定是否接受该订单.研究发现,当市场需求接近或大于产能时,企业可从订单分层中获益;反之,市场需求显著小于产能时,分层不会带来额外收益.企业分层收益随需求增加或产能减少而递增,且与生产前置期呈倒U型关系.数值模拟发现,订单分层越精细,收益越大,且分层数约为需求与企业产能的比值时,订单分层收益接近最大值.展开更多
文摘Based on the characteristics of make-to-order manufacturing, risks in enterprises are analyzed, which are encountered when receiving orders. Dividing the whole process into three stages, this paper provides a qualitative explanation of the risky factors, failure rate, risk level and changes of each stage, and then provides a mathematic model of quantitative analysis by using fuzzy sets and an analytical hierarchy process. In the light of the relationship among the three stages, a formula for calculating risk levels of orders is worked out. Meanwhile, both economic and non-economic losses due to an order failure are considered in the assessment system. An actual case is analyzed using the described method. Suggestions for risk prevention or loss reduction are given.
文摘Change orders have a significant impact on many aspects of construction projects.They are known to be the primary cause of litigation in the construction industry.Change orders are almost inevitable due to the uniqueness of each project from many perspectives,such as the type of building,complexity of the design,human factors,and the available resources.Change orders are the formal mechanism to implement design changes during the execution phase.These changes are usually the outcome of lack of visualization by the owner,misunderstanding,miscommunication between different parties involved in the project,shortage in resources,and other factors.This research aims to investigate and rank causes,effects,and control measures of change orders in the construction industry in the U.S.This research presents the results of a questionnaire surveying owners,contractors,and consultants.A total of 123 industry professionals in the Architecture,Engineering,and Construction(AEC)field,with either significant or final decision-making authority on reviewing,issuing,and approving change orders responded to the survey.Results indicated that owners are the primary source followed by consultants and contractors,respectively.Some of the more important control measures identified in this research are collaboration and visualization technologies.
文摘研究按订单生产(make to order,MTO)模式下随机订单的准入策略.本文提出的准入决策方法分为两步,首先在考虑随机订单的不同属性基础上,采用TOPSIS(technique for order preference by similarity to an ideal solution)方法计算新到订单与理想订单的接近程度,以此作为订单的综合收益,从而对新订单进行分层排序;其次采用MDP(Markov decision process)模型分别计算接受和拒绝订单的期望收益,从而决定是否接受该订单.研究发现,当市场需求接近或大于产能时,企业可从订单分层中获益;反之,市场需求显著小于产能时,分层不会带来额外收益.企业分层收益随需求增加或产能减少而递增,且与生产前置期呈倒U型关系.数值模拟发现,订单分层越精细,收益越大,且分层数约为需求与企业产能的比值时,订单分层收益接近最大值.