In practice, some bugs have more impact than others and thus deserve more immediate attention. Due to tight schedule and limited human resources, developers may not have enough time to inspect all bugs. Thus, they oft...In practice, some bugs have more impact than others and thus deserve more immediate attention. Due to tight schedule and limited human resources, developers may not have enough time to inspect all bugs. Thus, they often concentrate on bugs that are highly impactful. In the literature, high-impact bugs are used to refer to the bugs which appear at unexpected time or locations and bring more unexpected effects （i.e., surprise bugs）, or break pre-existing functionalities and destroy the user experience （i.e., breakage bugs）. Unfortunately, identifying high-impact bugs from thousands of bug reports in a bug tracking system is not an easy feat. Thus, an automated technique that can identify high-impact bug reports can help developers to be aware of them early, rectify them quickly, and minimize the damages they cause. Considering that only a small proportion of bugs are high-impact bugs, the identification of high-impact bug reports is a difficult task. In this paper, we propose an approach to identify high-impact bug reports by leveraging imbalanced learning strategies. We investigate the effectiveness of various variants, each of which combines one particular imbalanced learning strategy and one particular classification algorithm. In particular, we choose four widely used strategies for dealing with imbalanced data and four state-of-the-art text classification algorithms to conduct experiments on four datasets from four different open source projects. We mainly perform an analytical study on two types of high-impact bugs, i.e., surprise bugs and breakage bugs. The results show that different variants have different performances, and the best performing variants SMOTE （synthetic minority over-sampling technique） ＋ KNN （K-nearest neighbours） for surprise bug identification and RUS （random under-sampling） ＋ NB （naive Bayes） for breakage bug identification outperform the Fl-scores of the two state-of-the-art approaches by Thung et al. and Garcia and Shihab.展开更多
The chemical modification of conventional acrylic resin by butadiene-styrene rubber to get high-impact acrylic resin has not been completely effective due to its potential bad influence on the resistance of bending or...The chemical modification of conventional acrylic resin by butadiene-styrene rubber to get high-impact acrylic resin has not been completely effective due to its potential bad influence on the resistance of bending or flexural and also the toughness of acrylic resin substance for the base of denture.So,to overcome this detrimental effect of rubber modification of acrylic resin,we tried to reinforce it in this research by the addition of titanium oxide and aluminum oxide nanoparticle mixture to the liquid(monomer)of acrylic resin(high-impact)with sonication at 3 wt%(TiO_(2):Al_(2)O_(3) ratio1:1)which was then blended with polymer(powder)of acrylic resin using conventional procedure to form nanocomposite.40 specimen of two groups(20 for each group)according to the performed property,20 specimens for flexural strength group and 20 specimens for impact strength group were prepared.Each group was divided into two subgroups,control group A:10 samples of pure high-impact acrylic,and study group B:10 samples of modified high-impact acrylic resin by 3wt%nanoparticle mixture.Testing of the flexural strength was examined by flexural testing universal machine(Instron),while testing of the impact strength was examined by impact testing Charpy's machine.The results were gathered from the tests and translated by statistical program(SPSS version 20)for analysis.The flexural strength and the impact strength increased with high significance upon the addition of 3 wt%nanoparticle mixture,according to t-test(Two-Sample Assuming Unequal Variances)and p-value.展开更多
Kangbao County is located in the northwest of Bashang in Hebei Province,which is a sub-arid area in the middle temperate zone,with a cold and arid climate and frequent disastrous weather.The meteorological data of Kan...Kangbao County is located in the northwest of Bashang in Hebei Province,which is a sub-arid area in the middle temperate zone,with a cold and arid climate and frequent disastrous weather.The meteorological data of Kangbao County Meteorological Station from 1994 to 2023 were selected,and the meteorological elements such as air pressure,temperature,precipitation,wind,relative humidity,sunshine,thunderstorm,hail,gale,rainstorm,fog,and snow cover were counted.The climate background analysis and high-impact weather analysis were carried out in combination with the topographic characteristics,geographical location,and climate characteristics.The results of meteorological sensitivity survey in the park showed that industries such as food,agriculture and new energy are very sensitive to temperature.During the visit to the enterprises in the park,it was found that heavy precipitation,snow,strong winds and hail had a great impact on many industries,and it was recommended to carry out long-term planning and reasonable design of buildings.It should pay close attention to forecasts and early warnings,formulate emergency plans for high-impact weather defense,and actively take preventive measures.展开更多
基金This work is supported by the National Natural Science Foundation of China under Grant Nos. 61602403 and 61402406 and the National Key Technology Research and Development Program of the Ministry of Science and Technology of China under Grant No. 2015BAH17F01.
文摘In practice, some bugs have more impact than others and thus deserve more immediate attention. Due to tight schedule and limited human resources, developers may not have enough time to inspect all bugs. Thus, they often concentrate on bugs that are highly impactful. In the literature, high-impact bugs are used to refer to the bugs which appear at unexpected time or locations and bring more unexpected effects （i.e., surprise bugs）, or break pre-existing functionalities and destroy the user experience （i.e., breakage bugs）. Unfortunately, identifying high-impact bugs from thousands of bug reports in a bug tracking system is not an easy feat. Thus, an automated technique that can identify high-impact bug reports can help developers to be aware of them early, rectify them quickly, and minimize the damages they cause. Considering that only a small proportion of bugs are high-impact bugs, the identification of high-impact bug reports is a difficult task. In this paper, we propose an approach to identify high-impact bug reports by leveraging imbalanced learning strategies. We investigate the effectiveness of various variants, each of which combines one particular imbalanced learning strategy and one particular classification algorithm. In particular, we choose four widely used strategies for dealing with imbalanced data and four state-of-the-art text classification algorithms to conduct experiments on four datasets from four different open source projects. We mainly perform an analytical study on two types of high-impact bugs, i.e., surprise bugs and breakage bugs. The results show that different variants have different performances, and the best performing variants SMOTE （synthetic minority over-sampling technique） ＋ KNN （K-nearest neighbours） for surprise bug identification and RUS （random under-sampling） ＋ NB （naive Bayes） for breakage bug identification outperform the Fl-scores of the two state-of-the-art approaches by Thung et al. and Garcia and Shihab.
文摘The chemical modification of conventional acrylic resin by butadiene-styrene rubber to get high-impact acrylic resin has not been completely effective due to its potential bad influence on the resistance of bending or flexural and also the toughness of acrylic resin substance for the base of denture.So,to overcome this detrimental effect of rubber modification of acrylic resin,we tried to reinforce it in this research by the addition of titanium oxide and aluminum oxide nanoparticle mixture to the liquid(monomer)of acrylic resin(high-impact)with sonication at 3 wt%(TiO_(2):Al_(2)O_(3) ratio1:1)which was then blended with polymer(powder)of acrylic resin using conventional procedure to form nanocomposite.40 specimen of two groups(20 for each group)according to the performed property,20 specimens for flexural strength group and 20 specimens for impact strength group were prepared.Each group was divided into two subgroups,control group A:10 samples of pure high-impact acrylic,and study group B:10 samples of modified high-impact acrylic resin by 3wt%nanoparticle mixture.Testing of the flexural strength was examined by flexural testing universal machine(Instron),while testing of the impact strength was examined by impact testing Charpy's machine.The results were gathered from the tests and translated by statistical program(SPSS version 20)for analysis.The flexural strength and the impact strength increased with high significance upon the addition of 3 wt%nanoparticle mixture,according to t-test(Two-Sample Assuming Unequal Variances)and p-value.
文摘Kangbao County is located in the northwest of Bashang in Hebei Province,which is a sub-arid area in the middle temperate zone,with a cold and arid climate and frequent disastrous weather.The meteorological data of Kangbao County Meteorological Station from 1994 to 2023 were selected,and the meteorological elements such as air pressure,temperature,precipitation,wind,relative humidity,sunshine,thunderstorm,hail,gale,rainstorm,fog,and snow cover were counted.The climate background analysis and high-impact weather analysis were carried out in combination with the topographic characteristics,geographical location,and climate characteristics.The results of meteorological sensitivity survey in the park showed that industries such as food,agriculture and new energy are very sensitive to temperature.During the visit to the enterprises in the park,it was found that heavy precipitation,snow,strong winds and hail had a great impact on many industries,and it was recommended to carry out long-term planning and reasonable design of buildings.It should pay close attention to forecasts and early warnings,formulate emergency plans for high-impact weather defense,and actively take preventive measures.
