This paper proposes a collaborative design model based on operation semantics in a distributed computer-aided design (CAD) environment. The goal is to reduce time consumption in data format conversion and the requirem...This paper proposes a collaborative design model based on operation semantics in a distributed computer-aided design (CAD) environment. The goal is to reduce time consumption in data format conversion and the requirement of network bandwidth so as to improve the cooperative ability and the synchronization efficiency. Firstly, real-time collaborative design is reviewed and three kinds of real-time collaborative design models are discussed. Secondly, the concept of operation semantics is defined and the framework of an operation semantics model is presented. The operation semantics carries the original design data and actual operation process to express design intent and operation activity in conventional CAD systems. Finally, according to the operation semantics model, a CAD operation primitive is defined which can be retrieved from and mapped to the local CAD system operation commands; a distributed CAD collaborative architecture based on the model is presented, and an example is given to verify the model.展开更多
A novel forward-flyback converter employing two switches and two transformers is presented. Two diodes of the primary side enable the voltage stress of two switches to be clamped at the input voltage ,which is lower t...A novel forward-flyback converter employing two switches and two transformers is presented. Two diodes of the primary side enable the voltage stress of two switches to be clamped at the input voltage ,which is lower than that of a conventional forward-flyback converter. Two transformers offer the following advantages. Firstly, the turns of primary transformer winding are reduced to half of that of a conventional forward-flyback converter with a single transformer; Secondly, the use of two transformers enables the smaller low-profile cores to be utilized, thus facilitating a low-profile design. The unequal condition of turn ratios is compared with the equal condition of turn ratios. When two turn ratios are unequal, the power distribution between the two transformers can be easily designed. Finally, experimental results verify the above analyses.展开更多
To better remove the contamination on the surface of a heat-exchanger in urban sewage source heat pump system (USSHPS), this paper analyzes the feasibility of strong self-flushing on the basis of experiments and pre...To better remove the contamination on the surface of a heat-exchanger in urban sewage source heat pump system (USSHPS), this paper analyzes the feasibility of strong self-flushing on the basis of experiments and presents a new on-line self-flushing technique, which alternately flushes part of heat transfer tubes. In addition, operation principles and the structure of the new heat-exchanger are introduced and the feasible economi- cal and technological cleaning plans are given by design calculation and scheme comparison. The result shows that keeping each tube washed for one minute with 5 m/s, the operating cost is lower than ¥5 and when one flushing pump ahemately flushes 10-20 heat exchangers, the saved costs of flushing 10 tubes alternately are over 4 times of the increased costs.展开更多
This work was focused on the model-based design method of two-axis four-actuator(TAFA) fast steering mirror system(FSM), in order to improve the design efficiency. The structure and operation principle commonality of ...This work was focused on the model-based design method of two-axis four-actuator(TAFA) fast steering mirror system(FSM), in order to improve the design efficiency. The structure and operation principle commonality of normal TAFA FSM were investigated. Based on the structure and the commonality, the conditions of single-axis idea, high-frequency resonance and coupling were modeled gradually. Combining these models, a holonomic system model was established to reflect and predict the performance of TAFA FSM. A model-based design method was proposed based on the holonomic system model. The design flow and design concept of the method were described. In accordance with the method, a TAFA FSM was designed. Simulations and experiments of the FSM were done, and the results of them were compared. The compared results indicate that the holonomic system model can well reflect and predict the performance of TAFA FSM. The bandwidth of TAFA FSM is more than 250 Hz; adjust time is less than 15 ms;overshoot is less than 8%; position accuracy is better than 10 μrad; the FSM prototype can satisfy the requirements.展开更多
In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the di...In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the direction of industry development have been found out, and the even-drive washing technology has been studied out through adoption of hyperbolic impeller and suspended inner barrel structure, as well as high-efficiency drive and innovated control design. Thereby the problems with existing washing machines such as heavy twist and wear, uneven wash of clothes, long washing time, and high water and power consumption are solved.展开更多
This paper sets up a mathematical model of switching network and switching function by utilizing graph theory to describe the logical function of different paths.The function varies with open and closed states of air ...This paper sets up a mathematical model of switching network and switching function by utilizing graph theory to describe the logical function of different paths.The function varies with open and closed states of air doors in a complex mine air sub network, and the computer program for solving the switching function of complex networks are offered. It gives the method for discriminating a reversible branch in a complex network by means of the switching function, and the method of counter inverted logical control of airflow inversion by means of open and short circuit conversion of key branches. The research has solved the problem of the stablization of air flow for normal ventination and reversing ventination in a diagonal network.展开更多
The purpose of variable selection is to identify important predictors for response variables. Although there are many varieties of variable selection methods, almost all of them have a problem of not accounting for th...The purpose of variable selection is to identify important predictors for response variables. Although there are many varieties of variable selection methods, almost all of them have a problem of not accounting for the relationship between predictors. Therefore it would well happen that the selected subset of identified predictors leads to hard-to-interpret model consisted of only interaction terms. In design of experiments, the analysis is driven by the effect heredity principle which governs the relationship between an interaction and its corresponding main effects. In this paper, the authors extend the variable selection method the Lasso with effect heredity principle to its Bayesian version. In the example, the authors analyze the data obtained from typical screening design Plackett-Bunnan design and compare the result from the ordinary Bayesian Lasso and proposed method.展开更多
The energy crisis and global warming become severe issues. Solar-driven CO2 reduction provides a promising route to confront the predicaments, which has received much attention. The photoelectrochemical(PEC) process...The energy crisis and global warming become severe issues. Solar-driven CO2 reduction provides a promising route to confront the predicaments, which has received much attention. The photoelectrochemical(PEC) process,which can integrate the merits of both photocatalysis and electrocatalysis, boosts splendid talent for CO2 reduction with high efficiency and excellent selectivity. Recent several decades have witnessed the overwhelming development of PEC CO2 reduction. In this review, we attempt to systematically summarize the recent advanced design for PEC CO2 reduction. On account of basic principles and evaluation parameters, we firstly highlight the subtle construction for photocathodes to enhance the efficiency and selectivity of CO2 reduction, which includes the strategies for improving light utilization, supplying catalytic active sites and steering reaction pathway.Furthermore, diversiform novel PEC setups are also outlined.These exploited setups endow a bright window to surmount the intrinsic disadvantages of photocathode, showing promising potentials for future applications. Finally, we underline the challenges and key factors for the further development of PEC CO2 reduction that would enable more efficient designs for setups and deepen systematic understanding for mechanisms.展开更多
Biothiols are important species in physiological processes such as regulating protein structures, redox homeostasis and cell signalling. Alternation in the biothiol levels is associated with various pathological proce...Biothiols are important species in physiological processes such as regulating protein structures, redox homeostasis and cell signalling. Alternation in the biothiol levels is associated with various pathological processes, therefore non-invasive fluorescent probes with high specificity to biothiols are highly desirable research utilities. Meanwhile, fluorescent probes with aggregationinduced emission properties(AIEgens) possess unique photophysical properties that allow modulation of the sensing process through controlling the aggregation-disaggregation or the intramolecular rotational motions of the fluorophores. Herein we review the recent progress in the development of biothiol-specific AIEgens. In particular, the molecular design principles to target different types of biothiols and the corresponding sensing mechanisms are discussed, along with the potential of the future design and development of multi-functional bioprobes.展开更多
文摘This paper proposes a collaborative design model based on operation semantics in a distributed computer-aided design (CAD) environment. The goal is to reduce time consumption in data format conversion and the requirement of network bandwidth so as to improve the cooperative ability and the synchronization efficiency. Firstly, real-time collaborative design is reviewed and three kinds of real-time collaborative design models are discussed. Secondly, the concept of operation semantics is defined and the framework of an operation semantics model is presented. The operation semantics carries the original design data and actual operation process to express design intent and operation activity in conventional CAD systems. Finally, according to the operation semantics model, a CAD operation primitive is defined which can be retrieved from and mapped to the local CAD system operation commands; a distributed CAD collaborative architecture based on the model is presented, and an example is given to verify the model.
文摘A novel forward-flyback converter employing two switches and two transformers is presented. Two diodes of the primary side enable the voltage stress of two switches to be clamped at the input voltage ,which is lower than that of a conventional forward-flyback converter. Two transformers offer the following advantages. Firstly, the turns of primary transformer winding are reduced to half of that of a conventional forward-flyback converter with a single transformer; Secondly, the use of two transformers enables the smaller low-profile cores to be utilized, thus facilitating a low-profile design. The unequal condition of turn ratios is compared with the equal condition of turn ratios. When two turn ratios are unequal, the power distribution between the two transformers can be easily designed. Finally, experimental results verify the above analyses.
基金Sponsored by the National Natural Science Foundation of China (Grant No.50578048)
文摘To better remove the contamination on the surface of a heat-exchanger in urban sewage source heat pump system (USSHPS), this paper analyzes the feasibility of strong self-flushing on the basis of experiments and presents a new on-line self-flushing technique, which alternately flushes part of heat transfer tubes. In addition, operation principles and the structure of the new heat-exchanger are introduced and the feasible economi- cal and technological cleaning plans are given by design calculation and scheme comparison. The result shows that keeping each tube washed for one minute with 5 m/s, the operating cost is lower than ¥5 and when one flushing pump ahemately flushes 10-20 heat exchangers, the saved costs of flushing 10 tubes alternately are over 4 times of the increased costs.
基金Projects(51135009)supported by the National Natural Science Foundation of China
文摘This work was focused on the model-based design method of two-axis four-actuator(TAFA) fast steering mirror system(FSM), in order to improve the design efficiency. The structure and operation principle commonality of normal TAFA FSM were investigated. Based on the structure and the commonality, the conditions of single-axis idea, high-frequency resonance and coupling were modeled gradually. Combining these models, a holonomic system model was established to reflect and predict the performance of TAFA FSM. A model-based design method was proposed based on the holonomic system model. The design flow and design concept of the method were described. In accordance with the method, a TAFA FSM was designed. Simulations and experiments of the FSM were done, and the results of them were compared. The compared results indicate that the holonomic system model can well reflect and predict the performance of TAFA FSM. The bandwidth of TAFA FSM is more than 250 Hz; adjust time is less than 15 ms;overshoot is less than 8%; position accuracy is better than 10 μrad; the FSM prototype can satisfy the requirements.
文摘In this paper, the development history and existing shortcomings of washing machines have been briefly described, the operating principle of the current washing machines has been analyzed, user requirements and the direction of industry development have been found out, and the even-drive washing technology has been studied out through adoption of hyperbolic impeller and suspended inner barrel structure, as well as high-efficiency drive and innovated control design. Thereby the problems with existing washing machines such as heavy twist and wear, uneven wash of clothes, long washing time, and high water and power consumption are solved.
文摘This paper sets up a mathematical model of switching network and switching function by utilizing graph theory to describe the logical function of different paths.The function varies with open and closed states of air doors in a complex mine air sub network, and the computer program for solving the switching function of complex networks are offered. It gives the method for discriminating a reversible branch in a complex network by means of the switching function, and the method of counter inverted logical control of airflow inversion by means of open and short circuit conversion of key branches. The research has solved the problem of the stablization of air flow for normal ventination and reversing ventination in a diagonal network.
文摘The purpose of variable selection is to identify important predictors for response variables. Although there are many varieties of variable selection methods, almost all of them have a problem of not accounting for the relationship between predictors. Therefore it would well happen that the selected subset of identified predictors leads to hard-to-interpret model consisted of only interaction terms. In design of experiments, the analysis is driven by the effect heredity principle which governs the relationship between an interaction and its corresponding main effects. In this paper, the authors extend the variable selection method the Lasso with effect heredity principle to its Bayesian version. In the example, the authors analyze the data obtained from typical screening design Plackett-Bunnan design and compare the result from the ordinary Bayesian Lasso and proposed method.
基金financially supported in part by the National Key R&D Program of China (2017YFA0207301)the National Basic Research Program of China (973 Program, 2014CB848900)+5 种基金the National Natural Science Foundation of China (21471141 and U1532135)the CAS Key Research Program of Frontier Sciences (QYZDB-SSW-SLH018)the CAS Interdisciplinary Innovation Team, the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology (2016FXCX003)the Recruitment Program of Global Experts, the CAS Hundred Talent Program, Anhui Provincial Natural Science Foundation (1708085QB26)China Postdoctoral Science Foundation (BH2060000034)the Fundamental Research Funds for the Central Universities (WK2060190064)
文摘The energy crisis and global warming become severe issues. Solar-driven CO2 reduction provides a promising route to confront the predicaments, which has received much attention. The photoelectrochemical(PEC) process,which can integrate the merits of both photocatalysis and electrocatalysis, boosts splendid talent for CO2 reduction with high efficiency and excellent selectivity. Recent several decades have witnessed the overwhelming development of PEC CO2 reduction. In this review, we attempt to systematically summarize the recent advanced design for PEC CO2 reduction. On account of basic principles and evaluation parameters, we firstly highlight the subtle construction for photocathodes to enhance the efficiency and selectivity of CO2 reduction, which includes the strategies for improving light utilization, supplying catalytic active sites and steering reaction pathway.Furthermore, diversiform novel PEC setups are also outlined.These exploited setups endow a bright window to surmount the intrinsic disadvantages of photocathode, showing promising potentials for future applications. Finally, we underline the challenges and key factors for the further development of PEC CO2 reduction that would enable more efficient designs for setups and deepen systematic understanding for mechanisms.
基金supported by Australian Research Council (DE170100058)Rebecca L. Cooper Medical Research Foundation
文摘Biothiols are important species in physiological processes such as regulating protein structures, redox homeostasis and cell signalling. Alternation in the biothiol levels is associated with various pathological processes, therefore non-invasive fluorescent probes with high specificity to biothiols are highly desirable research utilities. Meanwhile, fluorescent probes with aggregationinduced emission properties(AIEgens) possess unique photophysical properties that allow modulation of the sensing process through controlling the aggregation-disaggregation or the intramolecular rotational motions of the fluorophores. Herein we review the recent progress in the development of biothiol-specific AIEgens. In particular, the molecular design principles to target different types of biothiols and the corresponding sensing mechanisms are discussed, along with the potential of the future design and development of multi-functional bioprobes.