Effort estimation plays a crucial role in software development projects,aiding in resource allocation,project planning,and risk management.Traditional estimation techniques often struggle to provide accurate estimates...Effort estimation plays a crucial role in software development projects,aiding in resource allocation,project planning,and risk management.Traditional estimation techniques often struggle to provide accurate estimates due to the complex nature of software projects.In recent years,machine learning approaches have shown promise in improving the accuracy of effort estimation models.This study proposes a hybrid model that combines Long Short-Term Memory(LSTM)and Random Forest(RF)algorithms to enhance software effort estimation.The proposed hybrid model takes advantage of the strengths of both LSTM and RF algorithms.To evaluate the performance of the hybrid model,an extensive set of software development projects is used as the experimental dataset.The experimental results demonstrate that the proposed hybrid model outperforms traditional estimation techniques in terms of accuracy and reliability.The integration of LSTM and RF enables the model to efficiently capture temporal dependencies and non-linear interactions in the software development data.The hybrid model enhances estimation accuracy,enabling project managers and stakeholders to make more precise predictions of effort needed for upcoming software projects.展开更多
The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead t...The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead to changes in their approach to learning.Based on online intelligent learning,we investigated how the academic self-efficacy of nursing students affects their engagement with learning and explored the role of academic attribution as a mediator.Five hundred fifty-three nursing college students from Hebei and Hunan provinces in China participated in the online questionnaire.The results revealed that effort plays a mediating role in the relationship between academic self-efficacy and learning engagement.展开更多
Objective:The purpose of the study was to evaluate listening effort in adults who experience varied annoyance towards noise.Materials and methods:Fifty native Kannada-speaking adults aged 41e68 years participated.We e...Objective:The purpose of the study was to evaluate listening effort in adults who experience varied annoyance towards noise.Materials and methods:Fifty native Kannada-speaking adults aged 41e68 years participated.We evaluated the participant's acceptable noise level while listening to speech.Further,a sentence-final wordidentification and recall test at 0 dB SNR(less favorable condition)and 4 dB SNR(relatively favorable condition)was used to assess listening effort.The repeat and recall scores were obtained for each condition.Results:The regression model revealed that the listening effort increased by 0.6%at 0 dB SNR and by 0.5%at 4 dB SNR with every one-year advancement in age.Listening effort increased by 0.9%at 0 dB SNR and by 0.7%at 4 dB SNR with every one dB change in the value of Acceptable Noise Level(ANL).At 0 dB SNR and 4 dB SNR,a moderate and mild negative correlation was noted respectively between listening effort and annoyance towards noise when the factor age was controlled.Conclusion:Listening effort increases with age,and its effect is more in less favorable than in relatively favorable conditions.However,if the annoyance towards noise was controlled,the impact of age on listening effort was reduced.Listening effort correlated with the level of annoyance once the age effect was controlled.Furthermore,the listening effort was predicted from the ANL to a moderate degree.展开更多
In project management,effective cost estimation is one of the most cru-cial activities to efficiently manage resources by predicting the required cost to fulfill a given task.However,finding the best estimation results i...In project management,effective cost estimation is one of the most cru-cial activities to efficiently manage resources by predicting the required cost to fulfill a given task.However,finding the best estimation results in software devel-opment is challenging.Thus,accurate estimation of software development efforts is always a concern for many companies.In this paper,we proposed a novel soft-ware development effort estimation model based both on constructive cost model II(COCOMO II)and the artificial neural network(ANN).An artificial neural net-work enhances the COCOMO model,and the value of the baseline effort constant A is calibrated to use it in the proposed model equation.Three state-of-the-art publicly available datasets are used for experiments.The backpropagation feed-forward procedure used a training set by iteratively processing and training a neural network.The proposed model is tested on the test set.The estimated effort is compared with the actual effort value.Experimental results show that the effort estimated by the proposed model is very close to the real effort,thus enhanced the reliability and improving the software effort estimation accuracy.展开更多
Under the guidance of Daniel Gile's Effort Model, the paper makes an illustration of unbalanced effort distribution in the first phase of E-C consecutive interpretation through case studies, which are based on fie...Under the guidance of Daniel Gile's Effort Model, the paper makes an illustration of unbalanced effort distribution in the first phase of E-C consecutive interpretation through case studies, which are based on field interpretation practices. The paper explores the causes of improper effort distribution from three perspectives, namely knowledge of the language, extra-linguistic knowledge, and note-taking method. Then it renders several strategies to address improper effort distribution problems, aiming to offer some inspirations for the future field practice.展开更多
Microseismic effects during the transmission of seismic waves in coal and rock mass associated with mining operation were studied by on-site blasting tests and microseismic monitoring in LW704 of Southern Colliery,Aus...Microseismic effects during the transmission of seismic waves in coal and rock mass associated with mining operation were studied by on-site blasting tests and microseismic monitoring in LW704 of Southern Colliery,Australia,by using spread velocities,amplitudes and frequency contents as the main analysis parameters.The results show that the average P-wave velocity,mean values of combined maximal amplitudes and frequencies of the first arrivals are all reduced significantly along with goaf expanding and intensity weakening of overlying strata during mining process.A full roof fracturing can make the average P-wave velocities,combined maximal amplitudes and frequencies of first arrivals reduce to about 69.8%,92.2% and 60.0%,respectively.The reduction of the above seismic parameters reveals dynamic effects of the variation of strata structure and property to the wave transmission and energy dissipation of blasting wave.The research greatly benefits further study on stability of surrounding rock under the destructive effort by mine tremor,blasting,etc,and provides experimental basis for source relocation and parameter optimization of seismic monitoring as well.展开更多
Objective:To observe the clinical effect and protection of vascular endothelium of Zhixin-kang Capsule (ZXKC) in middle-aged and old people with unstable effort angina and hyperlipidemia. Methods: Sixty-five patients ...Objective:To observe the clinical effect and protection of vascular endothelium of Zhixin-kang Capsule (ZXKC) in middle-aged and old people with unstable effort angina and hyperlipidemia. Methods: Sixty-five patients with unstable effort angina were randomly divided into ZXKC group (34 cases) and control group (31 cases). Conventional western medical therapy was given to both groups, with ZXKC group receiving additional ZXKC treatment. Data of 20 healthy persons were taken as normal group. Forty-eight patients with hyperlipidemia were divided into ZXKC group treated with ZXKC (31 cases) and control group treated with Yixintong (17 cases). The changes of clinical symptoms and laboratory indexes in all the patients were observed before and after treatment. Results: In patients with unstable effort angina, the efficacy of treatment of ZXKC, the withdrawal rate of nitroglycerin, the relieving of symptoms, the improvement of the electrocardiogram, the counts of circulating endothelial cells, the content of platelet P-selectin, the content of plasma endothelin (ET), the activity of superoxide dismutase (SOD) and the activity of malonyldialdehyde (MDA) were all better than those in the control group. In patients with hyperlipidemia, there was no significant difference in lipids reduction between ZXKC group and the control group. In both groups, the total cholesterol (TC), triglyceride (TG), low density lipo-protein-cholesterol (LDL-C), lipoprotein(a) [Lp(a)] , ET, oxidized low density lipoprotein, MDA, arte-riosclerotic index (AI) all lowered obviously, while the SOD, HDL-C and calcitonin gene-related peptide (CGRP) were all elevated markedly. In the ZXKC group, the nitric oxide(NO) increased significantly whereas the ET/CGRP and ET/NO decreased markedly. The total effective rate in symptom relieving, the markedly effective rate, the reduction of TC, ET and ET/CGRP, and the elevation of SOD in ZXKC group were all superior to those in the control group. Conclusion: ZXKC could effectively resist myocardial ischemia, relieve angina, reduce blood lipids, protect vascular endothelial cells, inhibit the activation of platelets, and resist lipid peroxidation.展开更多
The software stage-effort estimation can be used to dynamically adjust software project schedule, further to help make the project finished on budget. This paper presents a grey model Verhulst based method for stage-e...The software stage-effort estimation can be used to dynamically adjust software project schedule, further to help make the project finished on budget. This paper presents a grey model Verhulst based method for stage-effort estimation during software development process, a bias correction technology was used to improve the estimation accuracy. The proposed method was evaluated with a large-scale industrial software engineering database. The results are very encouraging and indicate the method has considerable potential.展开更多
Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used...Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used respectively. Methods A total of 3 632 males and 1 706 females from 13 factories and companies in Henan province were recruited in this cross-sectional study. Perceived job stress was evaluated with the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire (Chinese version). Depressive symptoms were assessed by using the Center for Epidemiological Studies Depression Scale (CES-D). Results DC (demands/job control ratio) and ERI were shown to be independently associated with depressive symptoms. The outcome of low social support and overcommitment were similar. High DC and low social support (SS), high ERI and high overcommitment, and high DC and high ERI posed greater risks of depressive symptoms than each of them did alone. ERI model and SS model seem to be effective in estimating the risk of depressive symptoms if they are used respectively. Conclusion The DC had better performance when it was used in combination with low SS. The effect on physical demands was better than on psychological demands. The combination of DCS and ERI models could improve the risk estimate of depressive symptoms in humans.展开更多
In this study, we aimed to assess the relationship of socioeconomic status and acculturation with cardiovascular disease (CVD) risk profiles and CVD and examine the CVD risk factors associated with CVD. We used data...In this study, we aimed to assess the relationship of socioeconomic status and acculturation with cardiovascular disease (CVD) risk profiles and CVD and examine the CVD risk factors associated with CVD. We used data from the 2010 China Chronic Disease and Risk Factor Surveillance surveys, which consisted of a nationally representative sample of women. The following prevalence was found: myocardial infarction (MI):展开更多
Testing-effort(TE) and imperfect debugging(ID) in the reliability modeling process may further improve the fitting and prediction results of software reliability growth models(SRGMs). For describing the S-shaped...Testing-effort(TE) and imperfect debugging(ID) in the reliability modeling process may further improve the fitting and prediction results of software reliability growth models(SRGMs). For describing the S-shaped varying trend of TE increasing rate more accurately, first, two S-shaped testing-effort functions(TEFs), i.e.,delayed S-shaped TEF(DS-TEF) and inflected S-shaped TEF(IS-TEF), are proposed. Then these two TEFs are incorporated into various types(exponential-type, delayed S-shaped and inflected S-shaped) of non-homogeneous Poisson process(NHPP)SRGMs with two forms of ID respectively for obtaining a series of new NHPP SRGMs which consider S-shaped TEFs as well as ID. Finally these new SRGMs and several comparison NHPP SRGMs are applied into four real failure data-sets respectively for investigating the fitting and prediction power of these new SRGMs.The experimental results show that:(i) the proposed IS-TEF is more suitable and flexible for describing the consumption of TE than the previous TEFs;(ii) incorporating TEFs into the inflected S-shaped NHPP SRGM may be more effective and appropriate compared with the exponential-type and the delayed S-shaped NHPP SRGMs;(iii) the inflected S-shaped NHPP SRGM considering both IS-TEF and ID yields the most accurate fitting and prediction results than the other comparison NHPP SRGMs.展开更多
In a recent issue ot World Journal of Gastroenterology, Demeter et al., reported that in patients having both gastro-esophageal reflux disease (GERD) and obstructive sleep apnea (OSA), there was a positive correla...In a recent issue ot World Journal of Gastroenterology, Demeter et al., reported that in patients having both gastro-esophageal reflux disease (GERD) and obstructive sleep apnea (OSA), there was a positive correlation between endoscopic findings of GERD and the number of apneas and hypopneas per hour, namely apnea hypopnea index. They proposed that the severity of OSA and GERD are parallel to each other. The study of Demeter and colleagues is very important, not only for assessing reflux-induced esophageal damage in OSA,展开更多
In recent decades,many software reliability growth models(SRGMs) have been proposed for the engineers and testers in measuring the software reliability precisely.Most of them is established based on the non-homogene...In recent decades,many software reliability growth models(SRGMs) have been proposed for the engineers and testers in measuring the software reliability precisely.Most of them is established based on the non-homogeneous Poisson process(NHPP),and it is proved that the prediction accuracy of such models could be improved by adding the describing of characterization of testing effort.However,some research work indicates that the fault detection rate(FDR) is another key factor affects final software quality.Most early NHPPbased models deal with the FDR as constant or piecewise function,which does not fit the different testing stages well.Thus,this paper first incorporates a multivariate function of FDR,which is bathtub-shaped,into the NHPP-based SRGMs considering testing effort in order to further improve performance.A new model framework is proposed,and a stepwise method is used to apply the framework with real data sets to find the optimal model.Experimental studies show that the obtained new model can provide better performance of fitting and prediction compared with other traditional SRGMs.展开更多
By constructing influence model for communication effect of food safety risk in social media environment,the influences of different response manners taken by relevant enterprises on consumers' cognition and purch...By constructing influence model for communication effect of food safety risk in social media environment,the influences of different response manners taken by relevant enterprises on consumers' cognition and purchasing intention are analyzed,and influence mechanisms of response effort level,interaction and content reliability on consumers' attitudes are revealed. Based on quasi-experimental study with three kinds of response effort levels,it is found that content reliability,interaction and effort degree of enterprise response under negative information of food safety event have significant impacts on communication effect and consumers' purchasing intention.展开更多
How can we best find project changes that most improve project estimates? Prior solutions to this problem required the use of standard software process models that may not be relevant to some new project. Also, those ...How can we best find project changes that most improve project estimates? Prior solutions to this problem required the use of standard software process models that may not be relevant to some new project. Also, those prior solutions suffered from limited verification (the only way to assess the results of those studies was to run the recommendations back through the standard process models). Combining case-based reasoning and contrast set learning, the W system requires no underlying model. Hence, it is widely applicable (since there is no need for data to conform to some software process models). Also, W’s results can be verified (using holdout sets). For example, in the experiments reported here, W found changes to projects that greatly reduced estimate median and variance by up to 95% and 83% (respectively).展开更多
Software development effort estimation is considered a fundamental task for software development life cycle as well as for managing project cost, time and quality. Therefore, accurate estimation is a substantial facto...Software development effort estimation is considered a fundamental task for software development life cycle as well as for managing project cost, time and quality. Therefore, accurate estimation is a substantial factor in projects success and reducing the risks. In recent years, software effort estimation has received a considerable amount of attention from researchers?and became a challenge for software industry. In the last two decades, many researchers and practitioners proposed statistical and machine learning-based models for software effort estimation. In this work, Firefly Algorithm is proposed as a metaheuristic optimization method for optimizing the parameters of three COCOMO-based models. These models include the basic COCOMO model and other two models proposed in the literature as extensions of the basic COCOMO model. The developed estimation models are evaluated using different evaluation metrics. Experimental results show high accuracy and significant error minimization of Firefly Algorithm over other metaheuristic optimization algorithms including Genetic Algorithms and Particle Swarm Optimization.展开更多
文摘Effort estimation plays a crucial role in software development projects,aiding in resource allocation,project planning,and risk management.Traditional estimation techniques often struggle to provide accurate estimates due to the complex nature of software projects.In recent years,machine learning approaches have shown promise in improving the accuracy of effort estimation models.This study proposes a hybrid model that combines Long Short-Term Memory(LSTM)and Random Forest(RF)algorithms to enhance software effort estimation.The proposed hybrid model takes advantage of the strengths of both LSTM and RF algorithms.To evaluate the performance of the hybrid model,an extensive set of software development projects is used as the experimental dataset.The experimental results demonstrate that the proposed hybrid model outperforms traditional estimation techniques in terms of accuracy and reliability.The integration of LSTM and RF enables the model to efficiently capture temporal dependencies and non-linear interactions in the software development data.The hybrid model enhances estimation accuracy,enabling project managers and stakeholders to make more precise predictions of effort needed for upcoming software projects.
基金Research Project on Education and Teaching Reform at Hebei University of Chinese Medicine(22yb-45)Hebei Province Higher Education Teaching Reform Research and Practice Project(2021GJJG278)。
文摘The shift towards online intelligent learning has become the norm in education and is now a fundamental part of modern educational activities.However,this new model can influence students’learning behavior and lead to changes in their approach to learning.Based on online intelligent learning,we investigated how the academic self-efficacy of nursing students affects their engagement with learning and explored the role of academic attribution as a mediator.Five hundred fifty-three nursing college students from Hebei and Hunan provinces in China participated in the online questionnaire.The results revealed that effort plays a mediating role in the relationship between academic self-efficacy and learning engagement.
文摘Objective:The purpose of the study was to evaluate listening effort in adults who experience varied annoyance towards noise.Materials and methods:Fifty native Kannada-speaking adults aged 41e68 years participated.We evaluated the participant's acceptable noise level while listening to speech.Further,a sentence-final wordidentification and recall test at 0 dB SNR(less favorable condition)and 4 dB SNR(relatively favorable condition)was used to assess listening effort.The repeat and recall scores were obtained for each condition.Results:The regression model revealed that the listening effort increased by 0.6%at 0 dB SNR and by 0.5%at 4 dB SNR with every one-year advancement in age.Listening effort increased by 0.9%at 0 dB SNR and by 0.7%at 4 dB SNR with every one dB change in the value of Acceptable Noise Level(ANL).At 0 dB SNR and 4 dB SNR,a moderate and mild negative correlation was noted respectively between listening effort and annoyance towards noise when the factor age was controlled.Conclusion:Listening effort increases with age,and its effect is more in less favorable than in relatively favorable conditions.However,if the annoyance towards noise was controlled,the impact of age on listening effort was reduced.Listening effort correlated with the level of annoyance once the age effect was controlled.Furthermore,the listening effort was predicted from the ANL to a moderate degree.
基金This work was supported by the Technology development Program of MSS[No.S3033853].
文摘In project management,effective cost estimation is one of the most cru-cial activities to efficiently manage resources by predicting the required cost to fulfill a given task.However,finding the best estimation results in software devel-opment is challenging.Thus,accurate estimation of software development efforts is always a concern for many companies.In this paper,we proposed a novel soft-ware development effort estimation model based both on constructive cost model II(COCOMO II)and the artificial neural network(ANN).An artificial neural net-work enhances the COCOMO model,and the value of the baseline effort constant A is calibrated to use it in the proposed model equation.Three state-of-the-art publicly available datasets are used for experiments.The backpropagation feed-forward procedure used a training set by iteratively processing and training a neural network.The proposed model is tested on the test set.The estimated effort is compared with the actual effort value.Experimental results show that the effort estimated by the proposed model is very close to the real effort,thus enhanced the reliability and improving the software effort estimation accuracy.
文摘Under the guidance of Daniel Gile's Effort Model, the paper makes an illustration of unbalanced effort distribution in the first phase of E-C consecutive interpretation through case studies, which are based on field interpretation practices. The paper explores the causes of improper effort distribution from three perspectives, namely knowledge of the language, extra-linguistic knowledge, and note-taking method. Then it renders several strategies to address improper effort distribution problems, aiming to offer some inspirations for the future field practice.
基金Foundation item: Project(2010CB226805) supported by the National Basic Research Program of ChinaProject(2010QNA30) supported by the Fundamental Research Funds for the Central Universities of China+1 种基金Project supported by the Priority Academic Development Program of Jiangsu Higher Education,ChinaProjects(SZBF2011-6-B35,2012BAK04B06) supported by the National Twelfth Five-year Key Science & Technology Foundation of China
文摘Microseismic effects during the transmission of seismic waves in coal and rock mass associated with mining operation were studied by on-site blasting tests and microseismic monitoring in LW704 of Southern Colliery,Australia,by using spread velocities,amplitudes and frequency contents as the main analysis parameters.The results show that the average P-wave velocity,mean values of combined maximal amplitudes and frequencies of the first arrivals are all reduced significantly along with goaf expanding and intensity weakening of overlying strata during mining process.A full roof fracturing can make the average P-wave velocities,combined maximal amplitudes and frequencies of first arrivals reduce to about 69.8%,92.2% and 60.0%,respectively.The reduction of the above seismic parameters reveals dynamic effects of the variation of strata structure and property to the wave transmission and energy dissipation of blasting wave.The research greatly benefits further study on stability of surrounding rock under the destructive effort by mine tremor,blasting,etc,and provides experimental basis for source relocation and parameter optimization of seismic monitoring as well.
基金This study was funded by Natural Science Foundation of Shandong Province (No. Y97C22058)
文摘Objective:To observe the clinical effect and protection of vascular endothelium of Zhixin-kang Capsule (ZXKC) in middle-aged and old people with unstable effort angina and hyperlipidemia. Methods: Sixty-five patients with unstable effort angina were randomly divided into ZXKC group (34 cases) and control group (31 cases). Conventional western medical therapy was given to both groups, with ZXKC group receiving additional ZXKC treatment. Data of 20 healthy persons were taken as normal group. Forty-eight patients with hyperlipidemia were divided into ZXKC group treated with ZXKC (31 cases) and control group treated with Yixintong (17 cases). The changes of clinical symptoms and laboratory indexes in all the patients were observed before and after treatment. Results: In patients with unstable effort angina, the efficacy of treatment of ZXKC, the withdrawal rate of nitroglycerin, the relieving of symptoms, the improvement of the electrocardiogram, the counts of circulating endothelial cells, the content of platelet P-selectin, the content of plasma endothelin (ET), the activity of superoxide dismutase (SOD) and the activity of malonyldialdehyde (MDA) were all better than those in the control group. In patients with hyperlipidemia, there was no significant difference in lipids reduction between ZXKC group and the control group. In both groups, the total cholesterol (TC), triglyceride (TG), low density lipo-protein-cholesterol (LDL-C), lipoprotein(a) [Lp(a)] , ET, oxidized low density lipoprotein, MDA, arte-riosclerotic index (AI) all lowered obviously, while the SOD, HDL-C and calcitonin gene-related peptide (CGRP) were all elevated markedly. In the ZXKC group, the nitric oxide(NO) increased significantly whereas the ET/CGRP and ET/NO decreased markedly. The total effective rate in symptom relieving, the markedly effective rate, the reduction of TC, ET and ET/CGRP, and the elevation of SOD in ZXKC group were all superior to those in the control group. Conclusion: ZXKC could effectively resist myocardial ischemia, relieve angina, reduce blood lipids, protect vascular endothelial cells, inhibit the activation of platelets, and resist lipid peroxidation.
基金Supported by the National Natural Science Foundation of China (60673124)the National High Technology Research and Development Program of China (863 Program)(2006AA01Z183).
文摘The software stage-effort estimation can be used to dynamically adjust software project schedule, further to help make the project finished on budget. This paper presents a grey model Verhulst based method for stage-effort estimation during software development process, a bias correction technology was used to improve the estimation accuracy. The proposed method was evaluated with a large-scale industrial software engineering database. The results are very encouraging and indicate the method has considerable potential.
基金funded by Henan Provincial Health Science and Technology Key Projects(201001009)National Science and Technology Infrastructure Program(2006BAI06B 08),China
文摘Objective To investigate the co-effect of Demand-control-support (DCS) model and Effort-reward Imbalance (ERI) model on the risk estimation of depression in humans in comparison with the effects when they are used respectively. Methods A total of 3 632 males and 1 706 females from 13 factories and companies in Henan province were recruited in this cross-sectional study. Perceived job stress was evaluated with the Job Content Questionnaire and Effort-Reward Imbalance Questionnaire (Chinese version). Depressive symptoms were assessed by using the Center for Epidemiological Studies Depression Scale (CES-D). Results DC (demands/job control ratio) and ERI were shown to be independently associated with depressive symptoms. The outcome of low social support and overcommitment were similar. High DC and low social support (SS), high ERI and high overcommitment, and high DC and high ERI posed greater risks of depressive symptoms than each of them did alone. ERI model and SS model seem to be effective in estimating the risk of depressive symptoms if they are used respectively. Conclusion The DC had better performance when it was used in combination with low SS. The effect on physical demands was better than on psychological demands. The combination of DCS and ERI models could improve the risk estimate of depressive symptoms in humans.
文摘In this study, we aimed to assess the relationship of socioeconomic status and acculturation with cardiovascular disease (CVD) risk profiles and CVD and examine the CVD risk factors associated with CVD. We used data from the 2010 China Chronic Disease and Risk Factor Surveillance surveys, which consisted of a nationally representative sample of women. The following prevalence was found: myocardial infarction (MI):
基金supported by the Pre-research Foundation of CPLA General Equipment Department
文摘Testing-effort(TE) and imperfect debugging(ID) in the reliability modeling process may further improve the fitting and prediction results of software reliability growth models(SRGMs). For describing the S-shaped varying trend of TE increasing rate more accurately, first, two S-shaped testing-effort functions(TEFs), i.e.,delayed S-shaped TEF(DS-TEF) and inflected S-shaped TEF(IS-TEF), are proposed. Then these two TEFs are incorporated into various types(exponential-type, delayed S-shaped and inflected S-shaped) of non-homogeneous Poisson process(NHPP)SRGMs with two forms of ID respectively for obtaining a series of new NHPP SRGMs which consider S-shaped TEFs as well as ID. Finally these new SRGMs and several comparison NHPP SRGMs are applied into four real failure data-sets respectively for investigating the fitting and prediction power of these new SRGMs.The experimental results show that:(i) the proposed IS-TEF is more suitable and flexible for describing the consumption of TE than the previous TEFs;(ii) incorporating TEFs into the inflected S-shaped NHPP SRGM may be more effective and appropriate compared with the exponential-type and the delayed S-shaped NHPP SRGMs;(iii) the inflected S-shaped NHPP SRGM considering both IS-TEF and ID yields the most accurate fitting and prediction results than the other comparison NHPP SRGMs.
文摘In a recent issue ot World Journal of Gastroenterology, Demeter et al., reported that in patients having both gastro-esophageal reflux disease (GERD) and obstructive sleep apnea (OSA), there was a positive correlation between endoscopic findings of GERD and the number of apneas and hypopneas per hour, namely apnea hypopnea index. They proposed that the severity of OSA and GERD are parallel to each other. The study of Demeter and colleagues is very important, not only for assessing reflux-induced esophageal damage in OSA,
基金supported by the National Natural Science Foundation of China(61070220)the Anhui Provincial Natural Science Foundation(1408085MKL79)
文摘In recent decades,many software reliability growth models(SRGMs) have been proposed for the engineers and testers in measuring the software reliability precisely.Most of them is established based on the non-homogeneous Poisson process(NHPP),and it is proved that the prediction accuracy of such models could be improved by adding the describing of characterization of testing effort.However,some research work indicates that the fault detection rate(FDR) is another key factor affects final software quality.Most early NHPPbased models deal with the FDR as constant or piecewise function,which does not fit the different testing stages well.Thus,this paper first incorporates a multivariate function of FDR,which is bathtub-shaped,into the NHPP-based SRGMs considering testing effort in order to further improve performance.A new model framework is proposed,and a stepwise method is used to apply the framework with real data sets to find the optimal model.Experimental studies show that the obtained new model can provide better performance of fitting and prediction compared with other traditional SRGMs.
文摘By constructing influence model for communication effect of food safety risk in social media environment,the influences of different response manners taken by relevant enterprises on consumers' cognition and purchasing intention are analyzed,and influence mechanisms of response effort level,interaction and content reliability on consumers' attitudes are revealed. Based on quasi-experimental study with three kinds of response effort levels,it is found that content reliability,interaction and effort degree of enterprise response under negative information of food safety event have significant impacts on communication effect and consumers' purchasing intention.
文摘How can we best find project changes that most improve project estimates? Prior solutions to this problem required the use of standard software process models that may not be relevant to some new project. Also, those prior solutions suffered from limited verification (the only way to assess the results of those studies was to run the recommendations back through the standard process models). Combining case-based reasoning and contrast set learning, the W system requires no underlying model. Hence, it is widely applicable (since there is no need for data to conform to some software process models). Also, W’s results can be verified (using holdout sets). For example, in the experiments reported here, W found changes to projects that greatly reduced estimate median and variance by up to 95% and 83% (respectively).
文摘Software development effort estimation is considered a fundamental task for software development life cycle as well as for managing project cost, time and quality. Therefore, accurate estimation is a substantial factor in projects success and reducing the risks. In recent years, software effort estimation has received a considerable amount of attention from researchers?and became a challenge for software industry. In the last two decades, many researchers and practitioners proposed statistical and machine learning-based models for software effort estimation. In this work, Firefly Algorithm is proposed as a metaheuristic optimization method for optimizing the parameters of three COCOMO-based models. These models include the basic COCOMO model and other two models proposed in the literature as extensions of the basic COCOMO model. The developed estimation models are evaluated using different evaluation metrics. Experimental results show high accuracy and significant error minimization of Firefly Algorithm over other metaheuristic optimization algorithms including Genetic Algorithms and Particle Swarm Optimization.