Although it is recognized that the post-harvest system is most responsible for the loss of soybean quality,the real impact of this loss is still unknown.Brazilian regulation allows 15%and 30%of broken soybean for grou...Although it is recognized that the post-harvest system is most responsible for the loss of soybean quality,the real impact of this loss is still unknown.Brazilian regulation allows 15%and 30%of broken soybean for group I and group II(quality groups),respectively.However,the industry is not informed about the loss in the quality parameters of soybeans and its impacts during long-term storage.Therefore,the objective was to evaluate the effect of the breakage kernel percentage of soybean stored for 12 months.Content of 15% of breakage kernels did not affect soybean quality.However,content of 30% of breakage kernels affected significantly soybean quality,which was evidenced by the increase of up to 75% in moldy soybeans,72% in acidity,50% in leached solids,27% in electrical conductivity,and the decrease of up to 12% in soluble protein,6.4% in germination and 3.5% in thousand kernel weight after 8 months of storage.Although the legislation establishes a percentage limit,it is recommended to store soybeans with up to 15% breakage kernels.On the contrary,values higher than that can cause a significant reduction in soybean quality,resulting in commercial losses.展开更多
Low temperature(77 K)photoluminescence measurements have been performed on different GaAs substrates to evaluate the GaAs crystal quality.Several defect-related luminescence peaks have been observed,including 1.452 eV...Low temperature(77 K)photoluminescence measurements have been performed on different GaAs substrates to evaluate the GaAs crystal quality.Several defect-related luminescence peaks have been observed,including 1.452 eV,1.476 eV,1.326 eV peaks deriving from 78 meV GaAs antisite defects,and 1.372 eV,1.289 eV peaks resulting from As vacancy related defects.Changes in photoluminescence emission intensity and emission energy as a function of temperature and excitation power lead to the identification of the defect states.The luminescence mechanisms of the defect states were studied by photoluminescence spectroscopy and the growth quality of GaAs crystal was evaluated.展开更多
Based on standards and the expertise, 10 indicators such as crack, reinforcement and splash, etc. are selected for welds quality description. The indicators are classified into three categories： appearance defects, s...Based on standards and the expertise, 10 indicators such as crack, reinforcement and splash, etc. are selected for welds quality description. The indicators are classified into three categories： appearance defects, shape defects and weld defects, and corresponding fuzzy evaluation sets are designed. Membership functions of each indicator are determined with fuzzy inference system （FIS） editor in Matlab based on the actual welding experience. A two-stage fuzzy evaluation model for weld quality is established in Simulink. Finally, the model is tested through evaluating 7 different types of welds. The results show that fuzzy evaluation calculation can be simplified by combining Simulink with Matlab-FIS, and the evaluation results are more accurate and objective compared with the experts＇ subjective e＇, iluation.展开更多
Ethiopia has high livestock population and hence has high potential for hide and skin production. Likewise, in west Shewa Zone of the country there is high hide and skin production. But hides and skins are affected by...Ethiopia has high livestock population and hence has high potential for hide and skin production. Likewise, in west Shewa Zone of the country there is high hide and skin production. But hides and skins are affected by different types of defects that hampered effective and efficient utilization of these resources. Therefore, a study was conducted in Bako Tibe and Ilu Gelan districts of west Showa zone with the objectives to assess pre- and post-slaughter defects that influence hide and skin qualities. Primary data were collected from sample household heads, middlemen, butcheries, hotel/restaurants and tanneries using semi-structured interview and direct observations. All middlemen, butchery and hotel/restaurants in the study areas were employed for data collection while households were selected using simple random sampling techniques. Results of the study revealed that all household respondents reported absence of extension services on hide and skin management. The maximum pre-slaughter defect observed by households (87.2%), hotel/restaurants (91.3%), butcheries (93.3%) and middle men (90%) were due to ectoparasites. Out of the respondents 64.6%, 40% and 82.6% of respondents from household, butcheries and hotels/restaurants, respectively were slaughtered animals on the ground without stunning. The maximum post-slaughter defects observed during slaughtering by households (95.4%), hotel/restaurants (87.0%), and butcheries (86.7%) were dirt and flay cut. According to the respondents, 38.5 of the households kept hide and skin on the ground before marketing. It was found that the major post-slaughter defects of hide were flesh remnant (94.3%), dirty (74.3%), corduroying (71.4%), and flay cut (65.7%). Moreover, traditional animal husbandry and slaughtering practices, poor storage and preservation methods of raw hides and skins, the absence of slaughtering facility and extension service exacerbated the problem. Therefore, there is an urgent need for good animal management practices, animal transportation and slaughtering, and post slaughter hide and skins management.展开更多
In the early stage of software development,a software requirements specification(SRS)is essential,and whether the requirements are clear and explicit is the key.However,due to various reasons,there may be a large numb...In the early stage of software development,a software requirements specification(SRS)is essential,and whether the requirements are clear and explicit is the key.However,due to various reasons,there may be a large number of misunderstandings.To generate high-quality software requirements specifications,numerous researchers have developed a variety of ways to improve the quality of SRS.In this paper,we propose a questions extraction method based on SRS elements decomposition,which evaluates the quality of SRS in the form of numerical indicators.The proposed method not only evaluates the quality of SRSs but also helps in the detection of defects,especially the description problem and omission defects in SRSs.To verify the effectiveness of the proposed method,we conducted a controlled experiment to compare the ability of checklist-based review(CBR)and the proposed method in the SRS review.The CBR is a classicmethod of reviewing SRS defects.After a lot of practice and improvement for a long time,CBR has excellent review ability in improving the quality of software requirements specifications.The experimental results with 40 graduate studentsmajoring in software engineering confirmed the effectiveness and advantages of the proposed method.However,the shortcomings and deficiencies of the proposed method are also observed through the experiment.Furthermore,the proposed method has been tried out by engineers with practical work experience in software development industry and received good feedback.展开更多
Defect prediction is relatively a new research area of software quality assurance. A project team always aims to produce a quality product with zero or few defects. Quality of a product is correlated with the number o...Defect prediction is relatively a new research area of software quality assurance. A project team always aims to produce a quality product with zero or few defects. Quality of a product is correlated with the number of defects as well as it is limited by time and by money. So, defect prediction is very important in the field of software quality and software reliability. This paper gives you a vivid description about software defect prediction. It describes the key areas of software defect prediction practice, and highlights some key open issues for the future.展开更多
Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quali...Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quality is poor,the effective contact area between the gear mating surfaces decreases,affecting the stability of the fit and thus the transmission accuracy,so it is of great significance to optimize the surface quality of the contour bevel gear.This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method,and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece.Then,the surface defects on the machined surface of the workpiece are studied by SEM,and the causes of the surface defects are analyzed by EDS.After that,XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis,and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment.The research results are of great significance for improving the machining accuracy of contour bevel gears,reducing friction losses and improving transmission efficiency.展开更多
基金Coordenacao de Aperfeicoamento de Pessoal de Nível Superior - Brasil (CAPES)Fundacao de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS)+2 种基金Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)financed in part by Coordenacao de Aperfeicoamento de Pessoal de Nível Superior-Brasil(CAPES)-Finance code 001,Fundacao de Amparoa Pesquisa do Estado do Rio Grande do Sul(FAPERGS)-Finances code 17/2551-0000935-5,22/2551-0001051-2,21/2551-0002255-8Conselho Nacional de Desenvolvimento Científico e Tecnologico(CNPq)-Finance codes 205518/2018-4,312603/2018-5.
文摘Although it is recognized that the post-harvest system is most responsible for the loss of soybean quality,the real impact of this loss is still unknown.Brazilian regulation allows 15%and 30%of broken soybean for group I and group II(quality groups),respectively.However,the industry is not informed about the loss in the quality parameters of soybeans and its impacts during long-term storage.Therefore,the objective was to evaluate the effect of the breakage kernel percentage of soybean stored for 12 months.Content of 15% of breakage kernels did not affect soybean quality.However,content of 30% of breakage kernels affected significantly soybean quality,which was evidenced by the increase of up to 75% in moldy soybeans,72% in acidity,50% in leached solids,27% in electrical conductivity,and the decrease of up to 12% in soluble protein,6.4% in germination and 3.5% in thousand kernel weight after 8 months of storage.Although the legislation establishes a percentage limit,it is recommended to store soybeans with up to 15% breakage kernels.On the contrary,values higher than that can cause a significant reduction in soybean quality,resulting in commercial losses.
基金Project supported by the National Natural Science Foundation of China(Grant No.21972103)the National Key Research and Development Program of China(Grant No.2016YFB040183)Research and Development Program of Shanxi Province,China(Grant No.201703D111026)
文摘Low temperature(77 K)photoluminescence measurements have been performed on different GaAs substrates to evaluate the GaAs crystal quality.Several defect-related luminescence peaks have been observed,including 1.452 eV,1.476 eV,1.326 eV peaks deriving from 78 meV GaAs antisite defects,and 1.372 eV,1.289 eV peaks resulting from As vacancy related defects.Changes in photoluminescence emission intensity and emission energy as a function of temperature and excitation power lead to the identification of the defect states.The luminescence mechanisms of the defect states were studied by photoluminescence spectroscopy and the growth quality of GaAs crystal was evaluated.
基金This work was supported by National Natural Science Foundation of China （No. 50875088 ） and Foundation for Distinguished Young Teachers＇ Training of Guangdong（Yq2013106）.
文摘Based on standards and the expertise, 10 indicators such as crack, reinforcement and splash, etc. are selected for welds quality description. The indicators are classified into three categories： appearance defects, shape defects and weld defects, and corresponding fuzzy evaluation sets are designed. Membership functions of each indicator are determined with fuzzy inference system （FIS） editor in Matlab based on the actual welding experience. A two-stage fuzzy evaluation model for weld quality is established in Simulink. Finally, the model is tested through evaluating 7 different types of welds. The results show that fuzzy evaluation calculation can be simplified by combining Simulink with Matlab-FIS, and the evaluation results are more accurate and objective compared with the experts＇ subjective e＇, iluation.
文摘Ethiopia has high livestock population and hence has high potential for hide and skin production. Likewise, in west Shewa Zone of the country there is high hide and skin production. But hides and skins are affected by different types of defects that hampered effective and efficient utilization of these resources. Therefore, a study was conducted in Bako Tibe and Ilu Gelan districts of west Showa zone with the objectives to assess pre- and post-slaughter defects that influence hide and skin qualities. Primary data were collected from sample household heads, middlemen, butcheries, hotel/restaurants and tanneries using semi-structured interview and direct observations. All middlemen, butchery and hotel/restaurants in the study areas were employed for data collection while households were selected using simple random sampling techniques. Results of the study revealed that all household respondents reported absence of extension services on hide and skin management. The maximum pre-slaughter defect observed by households (87.2%), hotel/restaurants (91.3%), butcheries (93.3%) and middle men (90%) were due to ectoparasites. Out of the respondents 64.6%, 40% and 82.6% of respondents from household, butcheries and hotels/restaurants, respectively were slaughtered animals on the ground without stunning. The maximum post-slaughter defects observed during slaughtering by households (95.4%), hotel/restaurants (87.0%), and butcheries (86.7%) were dirt and flay cut. According to the respondents, 38.5 of the households kept hide and skin on the ground before marketing. It was found that the major post-slaughter defects of hide were flesh remnant (94.3%), dirty (74.3%), corduroying (71.4%), and flay cut (65.7%). Moreover, traditional animal husbandry and slaughtering practices, poor storage and preservation methods of raw hides and skins, the absence of slaughtering facility and extension service exacerbated the problem. Therefore, there is an urgent need for good animal management practices, animal transportation and slaughtering, and post slaughter hide and skins management.
基金This work was partially supported by the Natural Science Foundation of Jiangsu Province under Grant No.BK20201462partially supported by the Scientific Research Support Project of Jiangsu Normal University under Grant No.21XSRX001.
文摘In the early stage of software development,a software requirements specification(SRS)is essential,and whether the requirements are clear and explicit is the key.However,due to various reasons,there may be a large number of misunderstandings.To generate high-quality software requirements specifications,numerous researchers have developed a variety of ways to improve the quality of SRS.In this paper,we propose a questions extraction method based on SRS elements decomposition,which evaluates the quality of SRS in the form of numerical indicators.The proposed method not only evaluates the quality of SRSs but also helps in the detection of defects,especially the description problem and omission defects in SRSs.To verify the effectiveness of the proposed method,we conducted a controlled experiment to compare the ability of checklist-based review(CBR)and the proposed method in the SRS review.The CBR is a classicmethod of reviewing SRS defects.After a lot of practice and improvement for a long time,CBR has excellent review ability in improving the quality of software requirements specifications.The experimental results with 40 graduate studentsmajoring in software engineering confirmed the effectiveness and advantages of the proposed method.However,the shortcomings and deficiencies of the proposed method are also observed through the experiment.Furthermore,the proposed method has been tried out by engineers with practical work experience in software development industry and received good feedback.
文摘Defect prediction is relatively a new research area of software quality assurance. A project team always aims to produce a quality product with zero or few defects. Quality of a product is correlated with the number of defects as well as it is limited by time and by money. So, defect prediction is very important in the field of software quality and software reliability. This paper gives you a vivid description about software defect prediction. It describes the key areas of software defect prediction practice, and highlights some key open issues for the future.
基金National Key R&D Program of China(Grant No.2019YFE0121300)Yancheng Hali Power Transmission and Intelligent Equipment Industrial Research Institute Project。
文摘Contour bevel gears have the advantages of high coincidence,low noise and large bearing capacity,which are widely used in automobile manufacturing,shipbuilding and construction machinery.However,when the surface quality is poor,the effective contact area between the gear mating surfaces decreases,affecting the stability of the fit and thus the transmission accuracy,so it is of great significance to optimize the surface quality of the contour bevel gear.This paper firstly analyzes the formation process of machined surface roughness of contour bevel gears on the basis of generating machining method,and dry milling experiments of contour bevel gears are conducted to analyze the effects of cutting speed and feed rate on the machined surface roughness and surface topography of the workpiece.Then,the surface defects on the machined surface of the workpiece are studied by SEM,and the causes of the surface defects are analyzed by EDS.After that,XRD is used to compare the microscopic grains of the machined surface and the substrate material for diffraction peak analysis,and the effect of cutting parameters on the microhardness of the workpiece machined surface is investigated by work hardening experiment.The research results are of great significance for improving the machining accuracy of contour bevel gears,reducing friction losses and improving transmission efficiency.
