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
The strain of bridges under traffic loads is time-varying and of small amplitude(~10^(-6)),which is a type of cumulative response and needs long-term continuous monitoring.To precisely capture the time-varying respons...The strain of bridges under traffic loads is time-varying and of small amplitude(~10^(-6)),which is a type of cumulative response and needs long-term continuous monitoring.To precisely capture the time-varying responses,a dynamic strain triboelectric nanogenerator(TENG)sensor with superior response capability,sensitivity,self-powered,and long-term stability is proposed in this paper.An analytical correlation between the structural strain response signal and the detected electrical signal is established for long-term continuous quantitative strain measurements based on the principles of contact electrification and electrostatic induction.A series of experiments are conducted to investigate the output performance of the proposed lateral-sliding mode TENG sensors.The results reveal that,with the loading condition with frequencies lower than 10 Hz,the time-varying strain responses of the steel bridge within the range of 3 to 150 microstrains can also be detected with high precision of 0.1 microstrains.And it achieves long-term stability after 10000 loading cycles compared with commercial sensors.The proposed novel sensing theory and method based on TENG technology can be applied as a new alternative approach for monitoring realtime structural strain information quantitatively with general applicability and feasibility for bridges.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.
基金supported by the National Key R&D Program of China(Grant No.2018YFB1600200)the National Natural Science Foundation of China(Grant Nos.52122801,11925206,and 51978609)+1 种基金Zhejiang Provincial Natural Science Foundation for Distinguished Young Scientists(Grant No.LR20E080003)。
文摘The strain of bridges under traffic loads is time-varying and of small amplitude(~10^(-6)),which is a type of cumulative response and needs long-term continuous monitoring.To precisely capture the time-varying responses,a dynamic strain triboelectric nanogenerator(TENG)sensor with superior response capability,sensitivity,self-powered,and long-term stability is proposed in this paper.An analytical correlation between the structural strain response signal and the detected electrical signal is established for long-term continuous quantitative strain measurements based on the principles of contact electrification and electrostatic induction.A series of experiments are conducted to investigate the output performance of the proposed lateral-sliding mode TENG sensors.The results reveal that,with the loading condition with frequencies lower than 10 Hz,the time-varying strain responses of the steel bridge within the range of 3 to 150 microstrains can also be detected with high precision of 0.1 microstrains.And it achieves long-term stability after 10000 loading cycles compared with commercial sensors.The proposed novel sensing theory and method based on TENG technology can be applied as a new alternative approach for monitoring realtime structural strain information quantitatively with general applicability and feasibility for bridges.
