The weighing system designed for large structure object is mainly composed of three parts. The part of hydraulic system is made up of hydraulic cylinders, high pressure hydraulic hoses and electric pumps; the part of ...The weighing system designed for large structure object is mainly composed of three parts. The part of hydraulic system is made up of hydraulic cylinders, high pressure hydraulic hoses and electric pumps; the part of computer controlling system comprises pressure sensors, displacement sensors, data acquisitions, RS 485 network and the computer controlling model; the part of loading system is composed of the fulcrum structure and the concrete girder. The measurement principle and composition of the weighing system are discussed in this paper. Credibility and security of the weighing system are fully considered during the design phase. The hydraulic system is controlled by pilot operated check valves in case of the sudden loss of system pressure. The states of all gauges and RS485 network are monitored by computer controlling system functioning in different modules. When the system is running incorrectly, it will be switched to manual mode and give alarm. The finite element method is employed to analyze fulcrum structure so that the system has enough intensity to be lifted. Hence the reliability of the whole system is enhanced.展开更多
We present a feasible scheme that realizes quantum computation using the two-level systems (TLSs) in Current-biased Josephson junction (CBJJ) under the present experimental technology. Effective manipulation of th...We present a feasible scheme that realizes quantum computation using the two-level systems (TLSs) in Current-biased Josephson junction (CBJJ) under the present experimental technology. Effective manipulation of the TLSs by CBJJ serving as register qubit can be obtained, such as initialization, single-qubit rotations, two-qubit gates, entanglement generation, and read out, etc. In addition, we also discuss the experimental feasibility and efficiency of the scheme.展开更多
The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind...The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind the flow disturbing element(hydraulic elbow), an ultrasonic flowmeter with applied head set in accordance with the Z-type system was used. For comparative purposes, a flow simulation for 3 different turbulence models(k-epsilon, SST and SSG) was performed. It was found that with a proper ultrasonic flowmeter heads configurations, it is possible to measure the flow rate disturbed by the hydraulic elbow at any distance from the source of the disturbance. It has to use appropriate correction factor that can be determined by knowing the flow velocity profile equation. Based on comparison of CFD simulation results with experimental data, the accuracy/purposefulness of using individual turbulence models in the case of discussed hydraulic installation was evaluated.展开更多
The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecologi...The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s).展开更多
The present work proposes a novel methodology for constructing coarse-grained (CG) models, which aims at minimizing the difference between CG model and the corresponding original system. The difference is defined as...The present work proposes a novel methodology for constructing coarse-grained (CG) models, which aims at minimizing the difference between CG model and the corresponding original system. The difference is defined as a functional of their equilibrium conformationaJ probability densities, then is estimated from equilibrium averages of many independent physical quantities denoted as basis functions. An orthonormalization strategy is adopted to get the independent basis functions from su^ciently preselected interesting physical quantities of the system. Thus the current method is named as probability density matching coarse-graining (PMCG) scheme, which effectively takes into account the overall cha,~acteristics of the original systems to construct CG model, and it is a rtatural improvement of the usual CG scheme wherein some physical quantities are intuitively chosen without considering their correlations. We verify the general PMCG framework in constructing a one-site CG water model from TIP3P model. Both structure of liquids and pressure of the TIP3P water system are found to be well reproduced at the same time in the constructed CG model.展开更多
文摘The weighing system designed for large structure object is mainly composed of three parts. The part of hydraulic system is made up of hydraulic cylinders, high pressure hydraulic hoses and electric pumps; the part of computer controlling system comprises pressure sensors, displacement sensors, data acquisitions, RS 485 network and the computer controlling model; the part of loading system is composed of the fulcrum structure and the concrete girder. The measurement principle and composition of the weighing system are discussed in this paper. Credibility and security of the weighing system are fully considered during the design phase. The hydraulic system is controlled by pilot operated check valves in case of the sudden loss of system pressure. The states of all gauges and RS485 network are monitored by computer controlling system functioning in different modules. When the system is running incorrectly, it will be switched to manual mode and give alarm. The finite element method is employed to analyze fulcrum structure so that the system has enough intensity to be lifted. Hence the reliability of the whole system is enhanced.
基金supported by National Natural Science Foundation of China under Grant No. 10905024Doctoral Startup Natural Science Foundation of Guangdong Province
文摘We present a feasible scheme that realizes quantum computation using the two-level systems (TLSs) in Current-biased Josephson junction (CBJJ) under the present experimental technology. Effective manipulation of the TLSs by CBJJ serving as register qubit can be obtained, such as initialization, single-qubit rotations, two-qubit gates, entanglement generation, and read out, etc. In addition, we also discuss the experimental feasibility and efficiency of the scheme.
文摘The article is an attempt to compile the results of CFD liquid flow simulation through pipeline section containing hydraulic elbow with the results of ultrasonic flow measurements. To carry out the measurements behind the flow disturbing element(hydraulic elbow), an ultrasonic flowmeter with applied head set in accordance with the Z-type system was used. For comparative purposes, a flow simulation for 3 different turbulence models(k-epsilon, SST and SSG) was performed. It was found that with a proper ultrasonic flowmeter heads configurations, it is possible to measure the flow rate disturbed by the hydraulic elbow at any distance from the source of the disturbance. It has to use appropriate correction factor that can be determined by knowing the flow velocity profile equation. Based on comparison of CFD simulation results with experimental data, the accuracy/purposefulness of using individual turbulence models in the case of discussed hydraulic installation was evaluated.
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 51021066)the State Key Development Program for Basic Research of China (Grant No. 2010CB951102)
文摘The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s).
基金Supported by National Natural Science Foundation of China under Grant No.11175250
文摘The present work proposes a novel methodology for constructing coarse-grained (CG) models, which aims at minimizing the difference between CG model and the corresponding original system. The difference is defined as a functional of their equilibrium conformationaJ probability densities, then is estimated from equilibrium averages of many independent physical quantities denoted as basis functions. An orthonormalization strategy is adopted to get the independent basis functions from su^ciently preselected interesting physical quantities of the system. Thus the current method is named as probability density matching coarse-graining (PMCG) scheme, which effectively takes into account the overall cha,~acteristics of the original systems to construct CG model, and it is a rtatural improvement of the usual CG scheme wherein some physical quantities are intuitively chosen without considering their correlations. We verify the general PMCG framework in constructing a one-site CG water model from TIP3P model. Both structure of liquids and pressure of the TIP3P water system are found to be well reproduced at the same time in the constructed CG model.