Advances in meticulous dural closure technique remain a great challenge for watertight dural closure in the aged society,because the cerebrospinal fluid(CSF)leakage after spinal surgery is often accompanied with the d...Advances in meticulous dural closure technique remain a great challenge for watertight dural closure in the aged society,because the cerebrospinal fluid(CSF)leakage after spinal surgery is often accompanied with the disgusting wound infection,meningitis and pseudomeningocele.Here,a tetra-poly(ethylene glycol)(PEG)-based hydrogel sealant is developed with collective advantages of facile operation,high safety,quick set time,easy injectability,favorable mechanical strength and powerful tissue adhesion for effective sutureless dural closure during the surgery procedure.Impressively,this tetra-PEG sealant can instantaneously adhere to the irregular tissue surfaces even in a liquid environment,and effectively prevent or block off the intraoperative CSF leakage for sutureless dural closure and dura regeneration.Together,this sutureless tetra-PEG adhesive can be utilized as a very promising alternative for high-efficient watertight dural closure of the clinical patients who incidentally or deliberately undergo the durotomy during the spinal surgery.展开更多
The grating eddy current displacement sensor (GECDS) for distance or position measurement used in watertight electronic calipers was described. The sensor relies on repetitive variation of inductance against displacem...The grating eddy current displacement sensor (GECDS) for distance or position measurement used in watertight electronic calipers was described. The sensor relies on repetitive variation of inductance against displacement caused by the change of coupling areas between moving coils and static reflectors. The investigations focused on setting up and utilizing a computer model of the 3D eddy current fields and geometry to analyze causes of the production of measurement blind areas, and to investigate effects of the sensor parameters, such as axial gap between coils and reflectors, reflector length and reflector width on characteristics of the sensor. Simulation results indicated that the sensor has the smallest nonlinearity error of 0.15%, which agrees well with the experimental results.展开更多
按照某船的柴-柴联合动力装置(combined diesel and diesel,CODAD)主推进系统集成项目总体要求开展主推进系统集成设计。针对主推进系统非直线传动、破舱水密和并车控制要求,采用液力耦合器配合单调速器并车控制方案,相较于常见的液压...按照某船的柴-柴联合动力装置(combined diesel and diesel,CODAD)主推进系统集成项目总体要求开展主推进系统集成设计。针对主推进系统非直线传动、破舱水密和并车控制要求,采用液力耦合器配合单调速器并车控制方案,相较于常见的液压多片式摩擦离合器配合主从调速器并车控制方案,具有并车解列过程平稳、可靠、双机负荷分配均匀等优点。所设计的主推进系统实际应用情况良好。展开更多
Design of watertight subdivision inherently involves its optimization with the objective to increase the index "A" above its minimum required value. In view of a big popularity of probabilistic search methods such a...Design of watertight subdivision inherently involves its optimization with the objective to increase the index "A" above its minimum required value. In view of a big popularity of probabilistic search methods such as genetic algorithms, this task is intrinsically time consuming. Thus, even when an optimal subdivision layout (i.e. topology) is determined, it can be found that the optimal bulkhead positions can be a great challenge time-wise, often forcing designers to satisfy with suboptimal solutions. The fundamental reason why this happens is that the nature of the optimized function (e.g., index "A" as a function of bulkhead positions) is unknown and hence it has no effect upon the choice of optimization strategy, which therefore reflects subjective but not factual preferences. In this paper we study the nature of functional dependency between the subdivision index and bulkhead positions, as a simplest case, and indicate pertinent optimization strategies that consequently reduce the optimization time. In our study we use a cruise ship model to demonstrate the application results of our findings.展开更多
基金supported by the Ministry of Science and Technology of the People’s Republic of China(2018YFE0104200)National Natural Science Foundation of China(51873214,51973226,81871782 and 82002030)the Youth Innovation Promotion Association CAS(No.2019031)for financial support.
文摘Advances in meticulous dural closure technique remain a great challenge for watertight dural closure in the aged society,because the cerebrospinal fluid(CSF)leakage after spinal surgery is often accompanied with the disgusting wound infection,meningitis and pseudomeningocele.Here,a tetra-poly(ethylene glycol)(PEG)-based hydrogel sealant is developed with collective advantages of facile operation,high safety,quick set time,easy injectability,favorable mechanical strength and powerful tissue adhesion for effective sutureless dural closure during the surgery procedure.Impressively,this tetra-PEG sealant can instantaneously adhere to the irregular tissue surfaces even in a liquid environment,and effectively prevent or block off the intraoperative CSF leakage for sutureless dural closure and dura regeneration.Together,this sutureless tetra-PEG adhesive can be utilized as a very promising alternative for high-efficient watertight dural closure of the clinical patients who incidentally or deliberately undergo the durotomy during the spinal surgery.
文摘The grating eddy current displacement sensor (GECDS) for distance or position measurement used in watertight electronic calipers was described. The sensor relies on repetitive variation of inductance against displacement caused by the change of coupling areas between moving coils and static reflectors. The investigations focused on setting up and utilizing a computer model of the 3D eddy current fields and geometry to analyze causes of the production of measurement blind areas, and to investigate effects of the sensor parameters, such as axial gap between coils and reflectors, reflector length and reflector width on characteristics of the sensor. Simulation results indicated that the sensor has the smallest nonlinearity error of 0.15%, which agrees well with the experimental results.
文摘按照某船的柴-柴联合动力装置(combined diesel and diesel,CODAD)主推进系统集成项目总体要求开展主推进系统集成设计。针对主推进系统非直线传动、破舱水密和并车控制要求,采用液力耦合器配合单调速器并车控制方案,相较于常见的液压多片式摩擦离合器配合主从调速器并车控制方案,具有并车解列过程平稳、可靠、双机负荷分配均匀等优点。所设计的主推进系统实际应用情况良好。
文摘Design of watertight subdivision inherently involves its optimization with the objective to increase the index "A" above its minimum required value. In view of a big popularity of probabilistic search methods such as genetic algorithms, this task is intrinsically time consuming. Thus, even when an optimal subdivision layout (i.e. topology) is determined, it can be found that the optimal bulkhead positions can be a great challenge time-wise, often forcing designers to satisfy with suboptimal solutions. The fundamental reason why this happens is that the nature of the optimized function (e.g., index "A" as a function of bulkhead positions) is unknown and hence it has no effect upon the choice of optimization strategy, which therefore reflects subjective but not factual preferences. In this paper we study the nature of functional dependency between the subdivision index and bulkhead positions, as a simplest case, and indicate pertinent optimization strategies that consequently reduce the optimization time. In our study we use a cruise ship model to demonstrate the application results of our findings.