The paper starts with a brief overview to the necessity of sheet metal forming simulation and the complexity of automobile panel forming, then leads to finite element analysis (FEA) which is a powerful simulation too...The paper starts with a brief overview to the necessity of sheet metal forming simulation and the complexity of automobile panel forming, then leads to finite element analysis (FEA) which is a powerful simulation tool for analyzing complex three-dimensional sheet metal forming problems. The theory and features of the dynamic explicit finite element methods are introduced and the available various commercial finite element method codes used for sheet metal forming simulation in the world are discussed,and the civil and international status quo of automobile panel simulation as well. The front door outer panel of one certain new automobile is regarded as one example that the dynamic explicit FEM code Dynaform is used for the simulation of the front door outer panel forming process. Process defects such as ruptures are predicted. The improving methods can be given according to the simulation results. Foreground of sheet metal forming simulation is outlined.展开更多
In order to analyze and test the component-based web application and decide when to stop the testing process, the concept of coverage criteria and test requirement reduction approach are proposed. First, four adequacy...In order to analyze and test the component-based web application and decide when to stop the testing process, the concept of coverage criteria and test requirement reduction approach are proposed. First, four adequacy criteria are defined and subsumption relationships among them are proved. Then, a translation algorithm is presented to transfer the test model into a web application decision-to-decision graph（WADDGraph）which is used to reduce testing requirements. Finally, different sets of test requirements can be generated from WADDGraph by analyzing subsumption and equivalence relationships among edges based on different coverage criteria, and testers can select different test requirements according to different testing environments. The case study indicates that coverage criteria follow linear subsumption relationships in real web applications. Test requirements can be reduced more than 55% on average based on different coverage criteria and the size of test requirements increases with the increase in the complexity of the coverage criteria.展开更多
The effects of application of cassava alcohol anaerobic fermentation liquid and mulching of film on overwintering and next year's growth and yield of banana were investigated in this study.The results showed that ...The effects of application of cassava alcohol anaerobic fermentation liquid and mulching of film on overwintering and next year's growth and yield of banana were investigated in this study.The results showed that the application of cassava alcohol anaerobic fermentation liquid with COD concentration of 1 200-2 000 mg/L(900 m^3/hm^2) and mulching of film significantly increased the soil organic matter and available potassium contents in banana orchard,improved the cold resistance of banana seedlings,increased the pseudostem height,pseudostem circumference,green leaf number and chlorophyll content of next year's banana seedlings,brought the flower bud emergence period and harvest period forward,and significantly increased the yield per plant.展开更多
Spent mushroom substrates （SMS） are usually treated as wastes. One of the main beneficial uses of SMS is as soil amendment, after further composting, for horticulture. Avocado orchards in Northern Israel, are grown ...Spent mushroom substrates （SMS） are usually treated as wastes. One of the main beneficial uses of SMS is as soil amendment, after further composting, for horticulture. Avocado orchards in Northern Israel, are grown mainly on heavy clay soils, suffering from poor drainage and limited aeration. This situation can cause yield decrease and lead to tree＇s degeneration. In the present study, two soil cover （mulch） treatments were compared, in an avocado orchard, as means to solve this problem： SMS and cattle manure compost （CMC）. The yields of two avocado varieties were higher on SMS than CMC mulch. Thick growth of avocado roots was found in and under both mulch types. Soil＇s electrical conductivity （EC） values were high under both mulch types, although they later decreased, due to annual rainfall. There are treatments （leaching etc.） that can be used, for minimizing the increase of soil＇s salinity after SMS application. Enhancement of avocado root growth into and under the mulch can lead to improvement of avocado trees growth, especially on heavy un-drained soils. Therefore, SMS recycling is advantageous for both avocado and mushroom growers. The commercial utilization of SMS in avocado orchards should be done carefully, with monitoring its impact on soil＇s EC （salinity） and taking the needed measures to avoid unnecessary damages.展开更多
In this paper we study the problem of generation of surface waves produced due to a） rolling of the plate and b） presence of a line source in front of a fixed vertical plate. The amplitudes of radiated waves at larg...In this paper we study the problem of generation of surface waves produced due to a） rolling of the plate and b） presence of a line source in front of a fixed vertical plate. The amplitudes of radiated waves at large distance from the plate, in both cases, are obtained by a suitable application of Green＇s integral theorem. These are then studied graphically for various values of the ice cover parameter.展开更多
文摘The paper starts with a brief overview to the necessity of sheet metal forming simulation and the complexity of automobile panel forming, then leads to finite element analysis (FEA) which is a powerful simulation tool for analyzing complex three-dimensional sheet metal forming problems. The theory and features of the dynamic explicit finite element methods are introduced and the available various commercial finite element method codes used for sheet metal forming simulation in the world are discussed,and the civil and international status quo of automobile panel simulation as well. The front door outer panel of one certain new automobile is regarded as one example that the dynamic explicit FEM code Dynaform is used for the simulation of the front door outer panel forming process. Process defects such as ruptures are predicted. The improving methods can be given according to the simulation results. Foreground of sheet metal forming simulation is outlined.
基金The National Natural Science Foundation of China(No.90818027,60873050)the National High Technology Research andDevelopment Program of China (863 Program) (No.2009AA01Z147)+2 种基金Opening Foundation of State Key Laboratory Software Engineering in Wu-han University(No.SKLSE20080717)Opening Foundation of State KeyLaboratory for Novel Software Technology in Nanjing University(No.ZZ-KT2008F12)the Key Laboratory Foundation of Shanghai Municipal Science and Technology Commission (No.09DZ2272600)
文摘In order to analyze and test the component-based web application and decide when to stop the testing process, the concept of coverage criteria and test requirement reduction approach are proposed. First, four adequacy criteria are defined and subsumption relationships among them are proved. Then, a translation algorithm is presented to transfer the test model into a web application decision-to-decision graph（WADDGraph）which is used to reduce testing requirements. Finally, different sets of test requirements can be generated from WADDGraph by analyzing subsumption and equivalence relationships among edges based on different coverage criteria, and testers can select different test requirements according to different testing environments. The case study indicates that coverage criteria follow linear subsumption relationships in real web applications. Test requirements can be reduced more than 55% on average based on different coverage criteria and the size of test requirements increases with the increase in the complexity of the coverage criteria.
基金Supported by National Natural Science Foundation of China(31260461)2013 Guiding Fund for Ecological Guangxi Construction+2 种基金Guangxi Scientific Research and Technological Development Project(GKH 1346011-19)Students’Experimental Skills and Scientific and Technological Innovation Ability Training Fund of Guangxi University(SYJN20131513)Earmarked Fund for Nanning Station of Banana in Guangxi of China Agriculture Research System(nycytxcxtd-04-18)
文摘The effects of application of cassava alcohol anaerobic fermentation liquid and mulching of film on overwintering and next year's growth and yield of banana were investigated in this study.The results showed that the application of cassava alcohol anaerobic fermentation liquid with COD concentration of 1 200-2 000 mg/L(900 m^3/hm^2) and mulching of film significantly increased the soil organic matter and available potassium contents in banana orchard,improved the cold resistance of banana seedlings,increased the pseudostem height,pseudostem circumference,green leaf number and chlorophyll content of next year's banana seedlings,brought the flower bud emergence period and harvest period forward,and significantly increased the yield per plant.
文摘Spent mushroom substrates （SMS） are usually treated as wastes. One of the main beneficial uses of SMS is as soil amendment, after further composting, for horticulture. Avocado orchards in Northern Israel, are grown mainly on heavy clay soils, suffering from poor drainage and limited aeration. This situation can cause yield decrease and lead to tree＇s degeneration. In the present study, two soil cover （mulch） treatments were compared, in an avocado orchard, as means to solve this problem： SMS and cattle manure compost （CMC）. The yields of two avocado varieties were higher on SMS than CMC mulch. Thick growth of avocado roots was found in and under both mulch types. Soil＇s electrical conductivity （EC） values were high under both mulch types, although they later decreased, due to annual rainfall. There are treatments （leaching etc.） that can be used, for minimizing the increase of soil＇s salinity after SMS application. Enhancement of avocado root growth into and under the mulch can lead to improvement of avocado trees growth, especially on heavy un-drained soils. Therefore, SMS recycling is advantageous for both avocado and mushroom growers. The commercial utilization of SMS in avocado orchards should be done carefully, with monitoring its impact on soil＇s EC （salinity） and taking the needed measures to avoid unnecessary damages.
基金Supported by the Department of Science and Technology,Government of India for their financial support of this work through the SERC Fast Track Scheme for Young Scientist(No.SR/FTP/MS-037/2011)
文摘In this paper we study the problem of generation of surface waves produced due to a） rolling of the plate and b） presence of a line source in front of a fixed vertical plate. The amplitudes of radiated waves at large distance from the plate, in both cases, are obtained by a suitable application of Green＇s integral theorem. These are then studied graphically for various values of the ice cover parameter.
