Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and...Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and a project may fail if there are excessive costs and schedule overruns.COVID-19 has affected the software industry by reducing interactions between developers and customers.Such a lack of interaction is a key reason for the failure of software projects.Projects can also fail when customers do not know precisely what they want.Furthermore,selecting the unsuitable elicitation technique can also cause project failure.The present study,therefore,aimed to identify which requirements elicitation technique is the most cost-effective for large-scale projects when time to market is a critical issue or when the customer is not available.To that end,we conducted a systematic literature review on requirements elicitation techniques.Most primary studies identified introspection as the best technique,followed by survey and brainstorming.This finding suggests that introspection should be the first choice of elicitation technique,especially when the customer is not available or the project has strict time and cost constraints.Moreover,introspection should also be used as the starting point in the elicitation process of a large-scale project,and all known requirements should be elicited using this technique.展开更多
Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model w...Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model whether real-time contrast-enhanced ultrasound （CEUS） can quantitatively evaluate the hemodynamic changes of renal cortex in the early period.Methods The model of ARF was induced in 30 healthy New Zealand white rabbits （2.5-3.0 kg）,by intramuscular injection of 50% glycerin solution （12 ml/kg）.CEUS were performed on right kidneys before,6 and 24 hours after glycerin injection.CEUS quantitative indexes were measured in renal cortex using QLAB software.Comparisons between different stages were performed using paired t test.The sensitivity of CEUS in diagnosing ARF was compared with blood serum urea nitrogen （BUN）,serum creatinine （SCr） level and color Doppler flow imaging （CDFI）.Results Among quantitative indexes,time to peak （TTP） and area under curve （AUC） increased significantly from （5.86±2.57） seconds and （124.4±46.7） dB.s before glycerin injection to （7.66±2.05） seconds and （288.1±64.9） dB.s 6 hours after injection （P 〈0.05）.Slope rate of ascending curve （A） and descending curve （α） decreased slightly from （3.00±1.22） dB/s and （0.19±0.15） 1/s to （2.80±1.45） dB.s and （0.09±0.02） 1/s （P 〈0.05）.Twenty-four hours later,only AUC increased significantly from （124.4±46.7） dB.s to （466.2±52.2） dB.s （P〈0.05）.Conclusion Quantitative indexes of CEUS might be useful in predicting the hemodynamic changes of renal cortex in the early six hours of ARF model.展开更多
基金funding this work through research group no.RG-1441-490.
文摘Requirements elicitation is a fundamental phase of software development in which an analyst discovers the needs of different stakeholders and transforms them into requirements.This phase is cost-and time-intensive,and a project may fail if there are excessive costs and schedule overruns.COVID-19 has affected the software industry by reducing interactions between developers and customers.Such a lack of interaction is a key reason for the failure of software projects.Projects can also fail when customers do not know precisely what they want.Furthermore,selecting the unsuitable elicitation technique can also cause project failure.The present study,therefore,aimed to identify which requirements elicitation technique is the most cost-effective for large-scale projects when time to market is a critical issue or when the customer is not available.To that end,we conducted a systematic literature review on requirements elicitation techniques.Most primary studies identified introspection as the best technique,followed by survey and brainstorming.This finding suggests that introspection should be the first choice of elicitation technique,especially when the customer is not available or the project has strict time and cost constraints.Moreover,introspection should also be used as the starting point in the elicitation process of a large-scale project,and all known requirements should be elicited using this technique.
文摘Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model whether real-time contrast-enhanced ultrasound （CEUS） can quantitatively evaluate the hemodynamic changes of renal cortex in the early period.Methods The model of ARF was induced in 30 healthy New Zealand white rabbits （2.5-3.0 kg）,by intramuscular injection of 50% glycerin solution （12 ml/kg）.CEUS were performed on right kidneys before,6 and 24 hours after glycerin injection.CEUS quantitative indexes were measured in renal cortex using QLAB software.Comparisons between different stages were performed using paired t test.The sensitivity of CEUS in diagnosing ARF was compared with blood serum urea nitrogen （BUN）,serum creatinine （SCr） level and color Doppler flow imaging （CDFI）.Results Among quantitative indexes,time to peak （TTP） and area under curve （AUC） increased significantly from （5.86±2.57） seconds and （124.4±46.7） dB.s before glycerin injection to （7.66±2.05） seconds and （288.1±64.9） dB.s 6 hours after injection （P 〈0.05）.Slope rate of ascending curve （A） and descending curve （α） decreased slightly from （3.00±1.22） dB/s and （0.19±0.15） 1/s to （2.80±1.45） dB.s and （0.09±0.02） 1/s （P 〈0.05）.Twenty-four hours later,only AUC increased significantly from （124.4±46.7） dB.s to （466.2±52.2） dB.s （P〈0.05）.Conclusion Quantitative indexes of CEUS might be useful in predicting the hemodynamic changes of renal cortex in the early six hours of ARF model.
