摘要 :
This work presents the effects of wrapped rib on thermal hydraulic performance of supercriticalwater in square annular channel. Nine different wrapped pitches and four different cross-sections ofwrapped rib have been tested. The r...
展开
This work presents the effects of wrapped rib on thermal hydraulic performance of supercriticalwater in square annular channel. Nine different wrapped pitches and four different cross-sections ofwrapped rib have been tested. The results have been analyzed in terms of pressure drop, secondflow, peaks of temperature and outlet temperature uniformity in the square annular channel. Thereduction in the wrapped pitch is found to enhance the secondary flow velocity and turbulenceintensity, thereby enhancing the thermal mixing of coolant compared to that in smooth channel. Asa result, the temperature field is more uniform in each sub-channel of the channel. However, thereduction of wrapped pitch increases the friction factor. As the wrapped pitch reduce below 300mm,the pressure drop increases steeply. In the same condition of the wrapped pith, the Influence ofcross-section of wrapped rib on the pressure drop and secondary flow is very small, but it influencesthe peaks of wall temperature near rib. The triangle and rectangle with chamfering have the smallerwall temperature peaks than the rectangle and circle.
收起
摘要 :
This work presents the effects of wrapped rib on thermal hydraulic performance of supercriticalwater in square annular channel. Nine different wrapped pitches and four different cross-sections ofwrapped rib have been tested. The r...
展开
This work presents the effects of wrapped rib on thermal hydraulic performance of supercriticalwater in square annular channel. Nine different wrapped pitches and four different cross-sections ofwrapped rib have been tested. The results have been analyzed in terms of pressure drop, secondflow, peaks of temperature and outlet temperature uniformity in the square annular channel. Thereduction in the wrapped pitch is found to enhance the secondary flow velocity and turbulenceintensity, thereby enhancing the thermal mixing of coolant compared to that in smooth channel. Asa result, the temperature field is more uniform in each sub-channel of the channel. However, thereduction of wrapped pitch increases the friction factor. As the wrapped pitch reduce below 300mm,the pressure drop increases steeply. In the same condition of the wrapped pith, the Influence ofcross-section of wrapped rib on the pressure drop and secondary flow is very small, but it influencesthe peaks of wall temperature near rib. The triangle and rectangle with chamfering have the smallerwall temperature peaks than the rectangle and circle.
收起
摘要 :
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly, veraciously, and comprehensively. Two different remote sensing images are used to obtain the change informatio...
展开
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly, veraciously, and comprehensively. Two different remote sensing images are used to obtain the change information by using an object oriented analyzing method in Land Use/Cover Change. Data is gathered according to the images' resolution, characteristic, size and texture property of the earth surface objects. Meanwhile, the color, shape, smoothness, and compactness of the images are reviewed to form many-adjacent-pixel objects which contain more semantic information. Combined with the knowledge of land use classification and loading classifier of discriminate class, a characteristic space is defined to establish a knowledge base. Two or three different typical features are chosen to serve as the training samples, and a data base could be completed successfully. Non-segmented or error-segmented objects are adjusting into correct ones favorably. Analyzing the data, only the areas of the lands for construction purpose and reservoir & bottomland have been increased in the whole city, while the areas of arable land, river & lake land, woodland, grassland, and not exploited or developed land have been decreased in more or less degree,which means that a tendency to expansion has become more and more significant.
收起
摘要 :
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly,veraciously,and comprehensively.Two different remote sensing images are used to obtain the change information b...
展开
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly,veraciously,and comprehensively.Two different remote sensing images are used to obtain the change information by using an object oriented analyzing method in Land Use/Cover Change.Data is gathered according to the images' resolution,characteristic,size and texture property of the earth surface objects.Meanwhile,the color,shape,smoothness,and compactness of the images are reviewed to form many-adjacent-pixel objects which contain more semantic information.Combined with the knowledge of land use classification and loading classifier of discriminate class,a characteristic space is defined to establish a knowledge base.Two or three different typical features are chosen to serve as the training samples,and a data base could be completed successfully.Non-segmented or error-segmented objects are adjusting into correct ones favorably.Analyzing the data,only the areas of the lands for construction purpose and reservoir & bottomland have been increased in the whole city,while the areas of arable land,river & lake land,woodland,grassland,and not exploited or developed land have been decreased in more or less degree ,which means that a tendency to expansion has become more and more significant.
收起
摘要 :
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly, veraciously, and comprehensively. Two different remote sensing images are used to obtain the change informatio...
展开
Higher resolution remote sensor has already become the significant instrument to obtain the change information quickly, veraciously, and comprehensively. Two different remote sensing images are used to obtain the change information by using an object oriented analyzing method in Land Use/Cover Change. Data is gathered according to the images' resolution, characteristic, size and texture property of the earth surface objects. Meanwhile, the color, shape, smoothness, and compactness of the images are reviewed to form many-adjacent-pixel objects which contain more semantic information. Combined with the knowledge of land use classification and loading classifier of discriminate class, a characteristic space is defined to establish a knowledge base. Two or three different typical features are chosen to serve as the training samples, and a data base could be completed successfully. Non-segmented or error-segmented objects are adjusting into correct ones favorably. Analyzing the data, only the areas of the lands for construction purpose and reservoir & bottomland have been increased in the whole city, while the areas of arable land, river & lake land, woodland, grassland, and not exploited or developed land have been decreased in more or less degree ,which means that a tendency to expansion has become more and more significant.
收起
摘要 :
Nowadays, more and more manufacturing companies tend to provide users with not only products but also additional services, by which emerged a trend that manufacturing companies focus much more on knowledge service through the whol...
展开
Nowadays, more and more manufacturing companies tend to provide users with not only products but also additional services, by which emerged a trend that manufacturing companies focus much more on knowledge service through the whole process of product life cycle. This paper describes the background of the emerging of knowledge-intensive business services and knowledge-intensive manufacturing and explains how the concept of service extends to the manufacturing sector, which proves that category of knowledgeintensive services should not be confined to service industries and can be extended to many manufacturing companies. Furthermore, this paper summarizes the bundled model of service and products, which helps manufacturing companies to provide customers with greater value and establish its own competitive advantage. What's more, case of Dionex (China) Company has been taken as an example for better understanding the knowledge-intensive service happened in manufacturing.
收起
摘要 :
Considering the randomicity of daily passenger flow changes, the paper introduced an index of 'n-day' average passenger flow volume aimed to reflect a more representative and stable daily passenger flow.Using a ' 7-day' average vo...
展开
Considering the randomicity of daily passenger flow changes, the paper introduced an index of 'n-day' average passenger flow volume aimed to reflect a more representative and stable daily passenger flow.Using a ' 7-day' average volume, the paper analyzed changes of Shanghai metro passenger flow, and the change rate of daily volume against '7-day' average was used for analyzing the sudden changes of passenger flow before main holidays including the National Day, Labor's day, Christmas Day and New Year's Day.
收起
摘要 :
Information technology has gradually penetrated into tourism industry, and integrated with it rapidly. Previous studies mainly aimed at information technology as a driving force for the integration of the tourism industry, this pa...
展开
Information technology has gradually penetrated into tourism industry, and integrated with it rapidly. Previous studies mainly aimed at information technology as a driving force for the integration of the tourism industry, this paper from the perspective of industrial integration, builds the path model in which IT promotes the tourism industry to integrate and innovate. Meanwhile, it makes an empirical analysis on that IT drives tourism industry to converge with it based on the relationship of industry concentration degree and convergence degree. The results show that the tourism industry concentration degree and the integration degree between this two industry have no significant correlation, while information industry concentration degree and the integration degree between this two industry show a significant correlation, the correlation coefficient is 0.329. It is suggested that tourism industry has no significant leading role in promoting this two industry's convergence, while information industry manifests a strong role in promoting their convergence.
收起
摘要 :
According to fire protection safety system, such as students' dormitories, put forward a fire prediction method based on SVM to deduce the possibility and risk level, in which people's behavior state is combined with static fire f...
展开
According to fire protection safety system, such as students' dormitories, put forward a fire prediction method based on SVM to deduce the possibility and risk level, in which people's behavior state is combined with static fire factors. Then, the simulation results are shown the method is effective.
收起
原文获取