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Development and Experiment of Multi- functional Wood Dehumidification Dryer 被引量:2
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作者 谢拥群 张壁光 +1 位作者 常建民 霍光青 《Forestry Studies in China》 CAS 2001年第2期60-64,共5页
A multi functional wood dehumidification dryer has been developed recently. The dryer can carry out air dehumidification by using only one refrigeration system, in which heat supplying and moisture air are exhausted ... A multi functional wood dehumidification dryer has been developed recently. The dryer can carry out air dehumidification by using only one refrigeration system, in which heat supplying and moisture air are exhausted by changing the position of several air dampers. In this paper, the work principles and characteristics of the dehumidification dryer are introduced, and the testing results about the thermal engineering performance of the dehumidification dryer, as well as the experiment results of drying several species of lumbers are expounded. 展开更多
关键词 multi function dehumidification dryer heat pump refrigeration system
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Application of data fusion on multi-function earth drill
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作者 胡长胜 赵伟民 +3 位作者 李瑰贤 杨春蕾 牛红 胡长军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期89-92,共4页
taking the bucket of multi function earth drill as an example, combining with the conception of multi sensor integration and data fusion, adopting the terrene column chart and digging torque formula as control depende... taking the bucket of multi function earth drill as an example, combining with the conception of multi sensor integration and data fusion, adopting the terrene column chart and digging torque formula as control dependence, the detecting method of the earth drill’s working state is introduced. Multi sensor data fusion is done with the aid of BP neural network in Matlab. The data to be interfused are pre processed and the program of simulation and “point checking” is given. 展开更多
关键词 multi function earth drill multi sensor integration and data fusion normalization preprocessing simulation experiment
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Design of Drilling and Riveting Multi-functional End Effector for CFRP and Aluminum Components in Robotic Aircraft Assembly 被引量:6
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作者 Zhang Lin Tian Wei +4 位作者 Li Dawei Hong Peng Li Zhenyu Zhou Weixue Liao Wenhe 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期529-538,共10页
To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforc... To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength. 展开更多
关键词 robotic aircraft assembly CFRP and aluminum components automatic drilling and riveting multi-functional end effector online detection and adjustment
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Relationship between Multi-Output Partially Bent Functions and Multi-Output Bent Functions 被引量:2
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作者 ZHAO Yaqun JU Guizhi WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1887-1890,共4页
In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent function... In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent functions is given in Theorem 4, which includes Walsh spectrum expression and function expression. This shows that multi-output partially Bent functions and multi-output Bent functions can define each other in principle. So we obtain the general method to construct multi-output partially Bent functions from multi-output Bent functions. 展开更多
关键词 multi-output partially Bent functions multi-output Bent functions Walsh spectrum CONSTRUCTING
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Three-dimensional free vibration analysis of multi-directional functionally graded piezoelectric annular plates on elastic foundations via state space based differential quadrature method 被引量:3
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作者 M.H.YAS N.MOLOUDI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第4期439-464,共26页
The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different... The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different boundary conditions. The material properties are assumed to vary continuously along the radial and thickness directions and have exponent-law distribution. A semi-analytical approach named the state space based differential quadrature method (SSDQM) is used to provide an analytical solution along the thickness using the state space method (SSM) and an approximate solution along the radial direction using the one-dimensional differential quadrature method (DQM). The influence of the Winkler and shear stiffness of the foundation~ the material property graded variations, and the circumferential wave number on the nomdimensional natural frequency of multi-directional FGP annular plates is studied. 展开更多
关键词 multi-directional functionally graded PIEZOELECTRIC annular plate freevibration
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Two-Phase Genetic Algorithm Applied in the Optimization of Multi-Modal Function 被引量:5
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作者 Huang Yu-zhen, Kang Li-shan,Zhou Ai-minState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期259-264,共6页
This paper presents a two-phase genetic algorithm (TPGA) based on the multi- parent genetic algorithm (MPGA). Through analysis we find MPGA will lead the population' s evol vement to diversity or convergence accor... This paper presents a two-phase genetic algorithm (TPGA) based on the multi- parent genetic algorithm (MPGA). Through analysis we find MPGA will lead the population' s evol vement to diversity or convergence according to the population size and the crossover size, so we make it run in different forms during the global and local optimization phases and then forms TPGA. The experiment results show that TPGA is very efficient for the optimization of low-dimension multi-modal functions, usually we can obtain all the global optimal solutions. 展开更多
关键词 optimization of multi-modal function genetic algorithm global optimization local optimization
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A Two-Level Subspace Evolutionary Algorithm for Solving Multi-Modal Function Optimization Problems 被引量:3
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作者 Li Yan, Kang ZhuoComputation Center, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期249-252,共4页
In this paper, a new algorithm for solving multi-modal function optimization problems-two-level subspace evolutionary algorithm is proposed. In the first level, the improved GT algorithm is used to do global recombina... In this paper, a new algorithm for solving multi-modal function optimization problems-two-level subspace evolutionary algorithm is proposed. In the first level, the improved GT algorithm is used to do global recombination search so that the whole population can be separated into several niches according to the position of solutions; then, in the second level, the niche evolutionary strategy is used for local search in the subspaces gotten in the first level till solutions of the problem are found. The new algorithm has been tested on some hard problems and some good results are obtained. 展开更多
关键词 multi-modal function subspace search evolutionary algorithm
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Walsh Spectral Characteristics and the Auto-Correlation Function Characteristics of Forming Orthomorphic Permutations of Multi-Output Functions 被引量:4
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作者 ZHAO Yaqun WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1895-1898,共4页
Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalize... Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained. 展开更多
关键词 orthomorphic permutation multi-output functions walsh spectral auto-correlation function
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Multi-factor analysis of initial poor graft function after orthotopic liver transplantation 被引量:12
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作者 Chen, Hao Peng, Cheng-Hong +5 位作者 Shen, Bai-Yong Deng, Xia-Xing Shen, Chuan Xie, Jun-Jie Dong, Wei Li, Hong-Wei 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第2期141-146,共6页
BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study s... BACKGROUND: In the early period of orthotopic liver transplantation (OLT), initial poor graft function (IPGF) is one of the complications which leads to primary graft non-function (PGNF) in serious cases. This study set out to establish the clinical risk factors resulting in IPGF after OLT. METHODS: Eighty cases of OLT were analyzed. The IPGF group consisted of patients with alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) above 1500 IU/L within 72 hours after OLT, while those in the non-IPGF group had values below 1500 IU/L. Recipient-associated factors before OLT analyzed were age, sex, primary liver disease and Child-Pugh classification; factors analyzed within the peri-operative period were non-heart beating time (NHBT), cold ischemia time (CIT), rewarming ischemic time (RWIT), liver biopsy at the end of cold ischemia; and factors analyzed within 72 hours after OLT were ALT and/or AST values. A logistic regression model was applied to filter the possible factors resulting in IPGF. RESULTS: Donor NHBT, CIT and RWIT were significantly longer in the IPGF group than in the non-IPGF group; in the logistic regression model, NHBT was the risk factor leading to IPGF (P < 0.05), while CIT and RWIT were possible risk factors. In one case in the IPGF group, PGNF appeared with moderate hepatic steatosis. CONCLUSIONS: Longer NHBT is an important risk factor leading to IPGF, while serious steatosis in the donor liver, CIT and RWIT are potential risk factors. 展开更多
关键词 orthotopic liver transplantation poor liver function multi-factor analysis
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Correlation Degree and Correlation Coefficient of Multi-Output Functions 被引量:1
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作者 JUGui-zhi ZHAOYa-qun 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期195-198,共4页
We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlati... We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other. 展开更多
关键词 Key words multi output functions independency correlation degree BALANCE correlation coefficient
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Novel multi–SO_(3)H functionalized ionic liquids as highly efficient catalyst for synthesis of biodiesel 被引量:1
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作者 Meichen Li Jie Chen +3 位作者 Ling Li Changshen Ye Xiaocheng Lin Ting Qiu 《Green Energy & Environment》 SCIE CSCD 2021年第2期271-282,共12页
Biodiesel is an attractive alternative to fossil fuels due to the energy and environmental concerns. In this paper, seven different multi –SO_(3)H functionalized ILs based on the low-cost less-substituted amines, whi... Biodiesel is an attractive alternative to fossil fuels due to the energy and environmental concerns. In this paper, seven different multi –SO_(3)H functionalized ILs based on the low-cost less-substituted amines, which contained massive sites for functionalization of sulfonic acid groups and further treatment of sulfonate-based anions, were prepared as catalysts with high acidity and desirable catalytic activity for the synthesis of biodiesel from the esterification of oleic acid with methanol. The physicochemical properties of these acidic ILs were characterized by a variety of analytical techniques such as FT-IR, EA, TGA, and the Br?nsted acidity was well determined by UV–vis. Among the ILs prepared, [EDA-PS][P-TSA] showed the highest catalytic activity for esterification due to its high acidity and appropriate miscibility with reactants, with an ultrahigh97.58% conversion of oleic acid under the optimum conditions(i.e. reaction time, 1.8 h;catalyst amount, 3 wt%;alcohol/acid molar ratio, 13:1,temperature 70℃) acquired from the Box–Behnken response surface methodology. With the novel strategy of multi –SO_(3) H modification on ILs,our catalyst had an approaching or even superior oleic acid conversion rate compared to other reported catalysts with considerably lower catalyst dosage and shorter reaction time. More importantly, it also exhibited high generality for converting various FFA feedstocks into biodiesel with considerable conversion within 93.59–94.33% under a rather lower catalyst dosage, which showed the valuable potential for converting low-cost oils into biodiesel from an economic and environmental perspective. 展开更多
关键词 multi–SO_(3)H functionalized IL High acidity ESTERIFICATION BIODIESEL
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Stability control of multi-parameter adaptive wireless communication systems based on multi-Lyapunov function 被引量:1
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作者 Song Xiaoqi Dong Li +2 位作者 Li Wenfa Tong Tinging Lei Lei 《High Technology Letters》 EI CAS 2017年第4期375-383,共9页
With the occurrence of burst interference,bit error rate( BER) stability of the wireless communication system( WCS) always degrades significantly. To cope with it,a stability control algorithm is proposed,utilizing th... With the occurrence of burst interference,bit error rate( BER) stability of the wireless communication system( WCS) always degrades significantly. To cope with it,a stability control algorithm is proposed,utilizing the stability theory of switched systems,which is specifically applicable for multi-parameter adaptive WCS with spectrum sensing ability,and it is capable of stabilizing BER within a reasonable range. Firstly,WCS is modeled as a switched system. Then,based on the multi-Lyapunov function,controlling rules are presented to enable the switched system to satisfy stable condition asymptotically. Finally,analysis and numerical simulation results demonstrate that the switched WCS with the proposed controlling rules is superior to conventional power-controlled WCS with or without state feedback control in terms of stability performance. 展开更多
关键词 switched system stability control multi-Lyapunov function(MLF) power control burst interference
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Multi-functional optical fiber sensor system based on a dense wavelength division multiplexer
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作者 Yue-Xin Yin Zhifa Wu +4 位作者 Siwen Sun Liang Tian Xibin Wang Yuanda Wu Daming Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第7期222-224,共3页
We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain... We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain sensor, and a 48-channel DWDM.This system can monitor temperature and strain changes at the same time.The ranges of these two sensors are from-20℃ to 100℃ and from-1000 με to 2000 με, respectively.The sensitivities of the temperature sensor and strain sensor are 0.03572 nm/℃ and 0.03808 nm/N, respectively.With the aid of a broadband source and spectrometer,different kinds and ranges of parameters in the environment can be monitored by using suitable sensors. 展开更多
关键词 DENSE wavelength DIVISION multiplexer(DWDM) planar LIGHTWAVE circuit multi-functional SENSOR optical fiber SENSOR system
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Searching for an Optimized Single-objective Function Matching Multiple Objectives with Automatic Calibration of Hydrological Models
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作者 TIAN Fuqiang HU Hongchang +2 位作者 SUN Yu LI Hongyi LU Hui 《Chinese Geographical Science》 SCIE CSCD 2019年第6期934-948,共15页
In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies,... In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies, there is a general opinion that no single-objective function can represent all important characteristics of even one specific hydrological variable(e.g., streamflow).Thus hydrologists must turn to multi-objective calibration.In this study, we demonstrated that an optimized single-objective function can compromise multi-response modes(i.e., multi-objective functions) of the hydrograph, which is defined as summation of a power function of the absolute error between observed and simulated streamflow with the exponent of power function optimized for specific watersheds.The new objective function was applied to 196 model parameter estimation experiment(MOPEX) watersheds across the eastern United States using the semi-distributed Xinanjiang hydrological model.The optimized exponent value for each watershed was obtained by targeting four popular objective functions focusing on peak flows, low flows, water balance, and flashiness, respectively.Results showed that the optimized single-objective function can achieve a better hydrograph simulation compared to the traditional single-objective function Nash-Sutcliffe efficiency coefficient for most watersheds, and balance high flow part and low flow part of the hydrograph without substantial differences compared to multi-objective calibration.The proposed optimal single-objective function can be practically adopted in the hydrological modeling if the optimal exponent value could be determined a priori according to hydrological/climatic/landscape characteristics in a specific watershed. 展开更多
关键词 automatic calibration single-objective function multi-OBJECTIVE functions Xinanjiang MODEL HYDROLOGICAL MODEL
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A design and application of compound multi-functional sensor in wood-based panel processing
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作者 XU Kai-hong ZHOU Ding-guo 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期319-322,共4页
A compound multi-functional sensor was designed by the study on the on-line testing technology of wood-based panels, and its properties of shape, functions, size, resistance to special environment were studied in deta... A compound multi-functional sensor was designed by the study on the on-line testing technology of wood-based panels, and its properties of shape, functions, size, resistance to special environment were studied in details. The operational principles of different sensors, technical flow of manufacturing, development of software systems of special functions, and the assessments of technical specification were also be introduced. This sensor adopted many new technologies, such as the applications of piezoresistant effect and heat sensitive effect can effectively measure the pressure and temperature, digital signal processing technology was used to extract and treat signals, and resist interference, encapsulation technology was used to keep the normal run of sensor under a harsh environment. Thus, the on-line compound multi-functional temperature/pressure sensor can be applied better to supervise the production of wood-based panels. All technical specifications of the compound multi-functional sensor were tested and the results met the requirements of the equipments. 展开更多
关键词 Wood-based panel processing multi-functional sensor Piezoresistant effect Heat sensitive effect
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Quasi-distribution Appraisal about Finite Element Analysis of Multi-functional Structure Made of Honeycomb Sandwich Materials
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作者 王一多 SHI Xiaofei +1 位作者 XI Ping LANG Haitao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期30-34,共5页
A new appraisal method(QDA, quasi-distribution appraisal) which could be used to evaluate the finite element analysis of multi-functional structure made of honeycomb sandwich materials is developed based on sub-sect... A new appraisal method(QDA, quasi-distribution appraisal) which could be used to evaluate the finite element analysis of multi-functional structure made of honeycomb sandwich materials is developed based on sub-section Bezier curve. It is established by simulating the distribution histogram data obtained from the numerical finite element analysis values of a satellite component with sub-section Bezier curve. Being dealt with area normalization method, the simulation curve could be regarded as a kind of probability density function(PDF), its mathematical expectation and the variance could be used to evaluate the result of finite element analysis. Numerical experiments have indicated that the QDA method demonstrates the intrinsic characteristics of the finite element analysis of multi-functional structure made of honeycomb sandwich materials, as an appraisal method, it is effective and feasible. 展开更多
关键词 honeycomb sandwich materials multi-functional structure quasi-distribution finite element analysis
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Study on the Intensive Use of Rural Cemetery Lands from the Perspective of Multiple Functions
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作者 Li Mingping Yu Zhongxiang 《Asian Agricultural Research》 2014年第4期50-53,共4页
According to the investigation and study on the land use of different cemeteries in rural areas,the intensive land use of four cemeteries,including the public cemetery,traditional cemetery,vertical cemetery,and ecolog... According to the investigation and study on the land use of different cemeteries in rural areas,the intensive land use of four cemeteries,including the public cemetery,traditional cemetery,vertical cemetery,and ecological cemetery,was evaluated.According to the data analysis,it is suggested to choose right cemetery according the practical conditions of each area,to take full use the multiple functions of cemetery lands and improve the intensive use. 展开更多
关键词 RURAL CEMETERY land-using multi-functions Intensiv
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Analysis and Research on the phenomenon of multifunction clothing
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作者 MA Jinjin SUN Sun 《International English Education Research》 2016年第6期45-47,共3页
The changes of the times to update the mode of life, so that people in the material consumption at the same time. the more the pursuit of spiritual enjoyment of consumption."Multi function clothing" in a single prod... The changes of the times to update the mode of life, so that people in the material consumption at the same time. the more the pursuit of spiritual enjoyment of consumption."Multi function clothing" in a single product can transform a variety of clothing style,with multi - variability and fashion.Not only reduces the scale of production and people's pursuit of fashion personality contradiction between them, also make life and travel more lightweight, functional, and intelligent, increased interest and personality clothing experience. Its low energy consumption, high utilization and other advantages, but also the expression of the concept of low carbon environmental protection.Its characteristics conform to the development trend of the times and the concept of the times, it can also meet the diverse psychological demands of the consumers, and have great market potential. 展开更多
关键词 Low carbon design multi functional clothing Smart clothing
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Analysis of Dynamic Cross Response between Spindles in a Dual Spindle Type Multi-Functional Turning Machine
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作者 Y. H. Choi S. T. Kim +1 位作者 T. Y. Seo K. H. Kim 《Journal of Power and Energy Engineering》 2013年第7期20-24,共5页
In order to meet increasing demand for higher productivity and flexibility, recently many kinds of multi-functional machine tools, which are capable of multiple machining functions or different kinds of machining proc... In order to meet increasing demand for higher productivity and flexibility, recently many kinds of multi-functional machine tools, which are capable of multiple machining functions or different kinds of machining processes on one machine, have been developed and widely used in manufacturing industries. In this study, a multi-functional turning lathe, which has two spindles and two turrets so that multiple turning operations and various machining processes could be performed simultaneously, has been developed. Furthermore, the equations of correlation between whole responses and cross responses of the two spindles have been derived to examine to what extent the two spindles affect each other’s vibrations. 展开更多
关键词 multi-functional LATHE multi-Spindles Frequency RESPONSE CROSS RESPONSE FEM Structural ANALYSIS
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Agricultural Multifunctionality Evolution and Research into Issues concerning Agriculture,Countryside and Farmers
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作者 LIU Xin 《Asian Agricultural Research》 2012年第12期1-4,9,共5页
From the point of view of agricultural civilization, the history of human civilization is the history of the development of the agricultural civilization. Accompanied by social progress and development of the times, t... From the point of view of agricultural civilization, the history of human civilization is the history of the development of the agricultural civilization. Accompanied by social progress and development of the times, the function of agriculture also experiences the expansion and deepening. In terms of economy, there is a process from mechanized farming to industrialization, then to informatization, modernization and internationalization. The great rejuvenation of the Chinese nation has also experienced and witnessed this process. In terms of "agriculture, countryside and farmers", the content is complex, diverse, profound, sharp, and changing, constantly testing and challenging our wisdom. When the Document No.1 in 2007 targeted modern agriculture, it indicated that new connotation was integrated into agricultural multifunctionality, standing at a new starting point. At present, the function of agriculture is still deepening; there are tremendous achievements and outstanding problems concurrently in issues concerning agriculture, countryside and farmers. We take the agricultural multifunctionality as breakthrough point for exploration and research. 展开更多
关键词 multi-functional AGRICULTURE MODERN AGRICULTURE IS
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