The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disa...The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix (DSM) is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized.展开更多
文章以河谷城市甘肃省兰州市为例,在测度“三生”空间冲突强度并揭示多尺度分异机制的基础上提出冲突协调策略。结果显示:①“三生”空间格局演化与地域分异显著。生活空间的增加主要源于对生态空间和生产空间的侵占。②兰州市“三生”...文章以河谷城市甘肃省兰州市为例,在测度“三生”空间冲突强度并揭示多尺度分异机制的基础上提出冲突协调策略。结果显示:①“三生”空间格局演化与地域分异显著。生活空间的增加主要源于对生态空间和生产空间的侵占。②兰州市“三生”空间冲突时空演化与地类分异显著。时序上,“三生”空间冲突强度呈持续上升态势,整体处于基本可控级别;空间上,形成了“一心、两翼、多轴带”的空间冲突格局;就地类而言,城镇的生活空间与生产空间冲突水平较高。③兰州市“三生”空间冲突影响因素尺度效应和异质性明显。高程、坡度、地形起伏度等对“三生”空间冲突具有抑制作用;人口密度、人均G D P、夜间灯光指数等因素加剧了区域“三生”空间冲突程度。展开更多
为协助医护人员开展病区服务工作,提升患者临床康复体验,提出基于用户需求的产品服务系统设计方法。以病区场景下的物流机器人服务系统为研究对象,采用模糊Kano模型和熵权法确定用户需求类型及优先级;结合用户关键需求,进行产品外观与...为协助医护人员开展病区服务工作,提升患者临床康复体验,提出基于用户需求的产品服务系统设计方法。以病区场景下的物流机器人服务系统为研究对象,采用模糊Kano模型和熵权法确定用户需求类型及优先级;结合用户关键需求,进行产品外观与结构、人机交互模式及产品信息显示的设计改进,并采用逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)评估设计方案的可行性。研究结果表明:采用定量和定性相结合的设计方法有利于提升服务系统设计的客观性和准确性,为同类产品的服务系统设计提供参考。展开更多
Weighting model is the only valuation model of life cycle impact assessment(LCIA) profile now. It simplifies evaluation function into linear function, and makes the determination of weighting factor complicated. There...Weighting model is the only valuation model of life cycle impact assessment(LCIA) profile now. It simplifies evaluation function into linear function, and makes the determination of weighting factor complicated. Therefore the valuation of LCIA profile is the most critical and controversial step in life cycle assessment(LCA). Development on valuation models, which are understood easily and accepted widely, is urgently needed in the field of LCA. The modeling approaches for the linear evaluation function were summed up. The modeling approaches for the nonlinear evaluation function were set up by function approximation theory, which include choosing preference products, forming preference data, establishing artificial neural network(ANN) and training ANN by preference data. By selecting 7 material products as preference product, experience was done with modeling approaches of the nonlinear evaluation function. The results show that the modeling approaches and valuation model of the nonlinear evaluation function are more practical than the weighting model.展开更多
许多研究探索了与全球变化相关的生态系统功能的变化,但对生态系统功能变化的机制与途径了解较少。初级生产力是生态系统功能的重要组分,但关于氮(N)添加下荒漠草原植物群落初级生产力如何变化以及变化机制尚未明确,N是否通过影响生物...许多研究探索了与全球变化相关的生态系统功能的变化,但对生态系统功能变化的机制与途径了解较少。初级生产力是生态系统功能的重要组分,但关于氮(N)添加下荒漠草原植物群落初级生产力如何变化以及变化机制尚未明确,N是否通过影响生物多样性来影响荒漠草原初级生产力?为此,本研究在荒漠草原开展了为期4年的N添加控制实验(2018—2021年),试验处理包括对照和4个N添加水平(5、10、20和40 g m^(-2)a^(-1)),研究了N添加对荒漠草原物种多样性、功能多样性、初级生产力及其关系的影响。结果表明:(1)N添加处理(2018—2021年)改变了植物物种多样性及功能多样性,但年际间变化趋势不同。N添加处理第四年(2021年)荒漠草原植物功能多样性(Rao指数)、群落加权平均值-株高、功能均匀度和功能离散度均显著增加,而荒漠草原植物物种丰富度和Shannon-Wiener指数均显著降低。(2)N添加可以通过影响物种丰富度和功能多样性进而间接地促进荒漠草原初级生产力,但群落加权性状值-株高对初级生产力的影响是正效应,而物种丰富度和功能离散度对初级生产力的影响是负效应。(3)生物量比率假说更能解释荒漠草原植物群落初级生产力的变异。我们的研究表明了N添加主要通过改变群落内优势物种的功能性状来调节荒漠草原植物初级生产力。展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51375437)Zhejiang Provincial Natural Science Foundation of China(Grant No.LY12E05019)
文摘The current research of configurable product disassemblability focuses on disassemblability evaluation and disassembly sequence planning. Little work has been done on quantitative analysis of configurable product disassemblability. The disassemblability modeling technology for configurable product based on disassembly constraint relation weighted design structure matrix (DSM) is proposed. Major factors affecting the disassemblability of configurable product are analyzed, and the disassembling degrees between components in configurable product are obtained by calculating disassembly entropies such as joint type, joint quantity, disassembly path, disassembly accessibility and material compatibility. The disassembly constraint relation weighted DSM of configurable product is constructed and configuration modules are formed by matrix decomposition and tearing operations. The disassembly constraint relation in configuration modules is strong coupling, and the disassembly constraint relation between modules is weak coupling, and the disassemblability configuration model is constructed based on configuration module. Finally, taking a hydraulic forging press as an example, the decomposed weak coupling components are used as configuration modules alone, components with a strong coupling are aggregated into configuration modules, and the disassembly sequence of components inside configuration modules is optimized by tearing operation. A disassemblability configuration model of the hydraulic forging press is constructed. By researching the disassemblability modeling technology of product configuration design based on disassembly constraint relation weighted DSM, the disassembly property in maintenance, recycling and reuse of configurable product are optimized.
文摘文章以河谷城市甘肃省兰州市为例,在测度“三生”空间冲突强度并揭示多尺度分异机制的基础上提出冲突协调策略。结果显示:①“三生”空间格局演化与地域分异显著。生活空间的增加主要源于对生态空间和生产空间的侵占。②兰州市“三生”空间冲突时空演化与地类分异显著。时序上,“三生”空间冲突强度呈持续上升态势,整体处于基本可控级别;空间上,形成了“一心、两翼、多轴带”的空间冲突格局;就地类而言,城镇的生活空间与生产空间冲突水平较高。③兰州市“三生”空间冲突影响因素尺度效应和异质性明显。高程、坡度、地形起伏度等对“三生”空间冲突具有抑制作用;人口密度、人均G D P、夜间灯光指数等因素加剧了区域“三生”空间冲突程度。
文摘为协助医护人员开展病区服务工作,提升患者临床康复体验,提出基于用户需求的产品服务系统设计方法。以病区场景下的物流机器人服务系统为研究对象,采用模糊Kano模型和熵权法确定用户需求类型及优先级;结合用户关键需求,进行产品外观与结构、人机交互模式及产品信息显示的设计改进,并采用逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)评估设计方案的可行性。研究结果表明:采用定量和定性相结合的设计方法有利于提升服务系统设计的客观性和准确性,为同类产品的服务系统设计提供参考。
基金Project(50135020) supported by the National Natural Science Foundation of China Project(2001AA337010) supportedby the Hi tech Research and Development Program of China Project(0203) supported by the Key Grant Project of Ministry of Educationof Chi
文摘Weighting model is the only valuation model of life cycle impact assessment(LCIA) profile now. It simplifies evaluation function into linear function, and makes the determination of weighting factor complicated. Therefore the valuation of LCIA profile is the most critical and controversial step in life cycle assessment(LCA). Development on valuation models, which are understood easily and accepted widely, is urgently needed in the field of LCA. The modeling approaches for the linear evaluation function were summed up. The modeling approaches for the nonlinear evaluation function were set up by function approximation theory, which include choosing preference products, forming preference data, establishing artificial neural network(ANN) and training ANN by preference data. By selecting 7 material products as preference product, experience was done with modeling approaches of the nonlinear evaluation function. The results show that the modeling approaches and valuation model of the nonlinear evaluation function are more practical than the weighting model.
文摘许多研究探索了与全球变化相关的生态系统功能的变化,但对生态系统功能变化的机制与途径了解较少。初级生产力是生态系统功能的重要组分,但关于氮(N)添加下荒漠草原植物群落初级生产力如何变化以及变化机制尚未明确,N是否通过影响生物多样性来影响荒漠草原初级生产力?为此,本研究在荒漠草原开展了为期4年的N添加控制实验(2018—2021年),试验处理包括对照和4个N添加水平(5、10、20和40 g m^(-2)a^(-1)),研究了N添加对荒漠草原物种多样性、功能多样性、初级生产力及其关系的影响。结果表明:(1)N添加处理(2018—2021年)改变了植物物种多样性及功能多样性,但年际间变化趋势不同。N添加处理第四年(2021年)荒漠草原植物功能多样性(Rao指数)、群落加权平均值-株高、功能均匀度和功能离散度均显著增加,而荒漠草原植物物种丰富度和Shannon-Wiener指数均显著降低。(2)N添加可以通过影响物种丰富度和功能多样性进而间接地促进荒漠草原初级生产力,但群落加权性状值-株高对初级生产力的影响是正效应,而物种丰富度和功能离散度对初级生产力的影响是负效应。(3)生物量比率假说更能解释荒漠草原植物群落初级生产力的变异。我们的研究表明了N添加主要通过改变群落内优势物种的功能性状来调节荒漠草原植物初级生产力。