DQPSK modem has been chosen as the modem scheme in many mobile communication systems. A new signal processing technique of π/4-DQPSK modem based on software radio is discussed in this paper. Unlike many other softwar...DQPSK modem has been chosen as the modem scheme in many mobile communication systems. A new signal processing technique of π/4-DQPSK modem based on software radio is discussed in this paper. Unlike many other software radio solutions to the subject, we choose a universal digital radio baseband processor operating as the co-processor of DSP. Only the core algorithms for signal processing are implemented with DSP. Thus the computation burden on DSP is reduced significantly. Compared with the traditional ones, the technique mentioned in this paper is more promising and attractive. It is extremely compact and power-efficient, which is often required by a mobile communication system. The implementation of baseband signal processing for π/4-DQPSK modem on this platform is illustrated in detail. Special emphases are laid on the architecture of the system and the algorithms used in the baseband signal processing. Finally, some experimental results are presented and the performances of the signal processing and compensation algorithms are evaluated through computer simulations.展开更多
Software Process Workshop (SPW 2005) was held in Beijing on May 25-27, 2005. This paper introduces the motivation of organizing such a workshop, as well as its theme and paper gathering and review; and summarizes the ...Software Process Workshop (SPW 2005) was held in Beijing on May 25-27, 2005. This paper introduces the motivation of organizing such a workshop, as well as its theme and paper gathering and review; and summarizes the main content and insights of 11 keynote speeches, 30 regular papers in five sessions of “Process Content”, “Process Tools and Metrics”, “Process Management”, “Process Representation and Analysis”, and “Experience Reports”, 8 software development support tools demonstration, and the ending panel “Where Are We Now? Where Should We Go Next?”.展开更多
Due to the randomness and time dependence of the factors affecting software reliability, most software reliability models are treated as stochastic processes, and the non-homogeneous Poisson process(NHPP) is the most ...Due to the randomness and time dependence of the factors affecting software reliability, most software reliability models are treated as stochastic processes, and the non-homogeneous Poisson process(NHPP) is the most used one.However, the failure behavior of software does not follow the NHPP in a statistically rigorous manner, and the pure random method might be not enough to describe the software failure behavior. To solve these problems, this paper proposes a new integrated approach that combines stochastic process and grey system theory to describe the failure behavior of software. A grey NHPP software reliability model is put forward in a discrete form, and a grey-based approach for estimating software reliability under the NHPP is proposed as a nonlinear multi-objective programming problem. Finally, four grey NHPP software reliability models are applied to four real datasets, the dynamic R-square and predictive relative error are calculated. Comparing with the original single NHPP software reliability model, it is found that the modeling using the integrated approach has a higher prediction accuracy of software reliability. Therefore, there is the characteristics of grey uncertain information in the NHPP software reliability models, and exploiting the latent grey uncertain information might lead to more accurate software reliability estimation.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 order to assure quality and control process in the development of the aircraft collaborative design software, a maturity assessment model is proposed. The requirements designing—house of quality is designed to eva...In order to assure quality and control process in the development of the aircraft collaborative design software, a maturity assessment model is proposed. The requirements designing—house of quality is designed to evaluate the maturity degree of the solution, and the evaluation results can help to manage and control the development process. Furthermore, a fuzzy evaluation method based on the minimum deviation is proposed to deal with the fuzzy information. The quantitative evaluation result of the maturity degree can be calculated by optimizing the semantic discount factor aim for the minimum deviation. Finally, this model is illustrated and analyzed by an example study of the aircraft collaborative design software.展开更多
The technologies of software architecture are introduced, and the software analysis-and-design process is divided into requirement analysis, software architecture design and system design. Using these technologies, a ...The technologies of software architecture are introduced, and the software analysis-and-design process is divided into requirement analysis, software architecture design and system design. Using these technologies, a model of architecture-centric software analysis and design process（ACSADP） is proposed. Meanwhile, with regard to the completeness, consistency and correctness between the software requirements and design results, the theories of function and process control are applied to ACSADP. Finally, a model of integrated development environnment （IDE） for ACSADP is propcsed. It can be demonstrated by the practice that the model of ACSADP can aid developer to manage software process effectively and improve the quality of software analysis and design.展开更多
The simulation of underwater acoustic information flow is an important way to research sonar performance and its engagement effectiveness in the ocean environment.This paper analyzes the significance of modeling an op...The simulation of underwater acoustic information flow is an important way to research sonar performance and its engagement effectiveness in the ocean environment.This paper analyzes the significance of modeling an open and sophisticated simulation software architecture by object-oriented method,and introduces the modeling processes and expression method of simulation architecture.According to the requirements of simulation system and the underwater acoustic information flow,the logical architecture of simulation software system is modeled by the object-oriented method.A use-case view captured the system requirements.The logical view shows the logical architecture of software system.The simulation software is decomposed into the loose coupling constituent parts by layering and partitioning the packages for maintainability.The design patterns enabled the simulation software to have good expansibility and reusability.The simulation system involving multi-targets and multi-sonar is developed based on the architecture model.Practices show that the model meets the needs for simulating an open and sophisticated system.展开更多
Mathematical model of filling disk-shaped mold cavity in steady state was studied.And the mathematical model under vibration field was developed from the model in steady state.According to the model of filling disk-sh...Mathematical model of filling disk-shaped mold cavity in steady state was studied.And the mathematical model under vibration field was developed from the model in steady state.According to the model of filling disk-shaped mold cavity in steady state,the filling time,the distribution of velocity field and the pressure field were obtained.The analysis results from rheological analytic model were compared with the numerical simulation results using Moldflow software in the powder injection molding filling process.Through the comparison,it is found that it is unreasonable to neglect the influence of temperature when calculated the pressure changing with the time at the cavity gate,while it can be neglected in other situations such as calculating the distribution of the velocity fields.This provides a theoretical reference for the establishment of correct model both in steady state and under vibration force field in the future.展开更多
废塑料污染已经成为仅次于气候问题的第二大环境问题,废塑料的数量逐年递增。为了解决废塑料的环境污染问题,设计了废塑料化学升级制烯烃工艺的4条技术路线:废塑料气化经费-托合成制烯烃路线(PFTO),废塑料气化经一步法制烯烃路线(PZTO)...废塑料污染已经成为仅次于气候问题的第二大环境问题,废塑料的数量逐年递增。为了解决废塑料的环境污染问题,设计了废塑料化学升级制烯烃工艺的4条技术路线:废塑料气化经费-托合成制烯烃路线(PFTO),废塑料气化经一步法制烯烃路线(PZTO),废塑料气化经甲醇制烯烃路线(PMTO),废塑料裂解经加氢裂化制烯烃路线(PPTO)。为验证其可行性,对4条技术路线进行了化工流程模拟,采用技术经济性分析方法对比了4条技术路线的能源效率、经济性、CO_(2)排放量和碳原子利用效率等参数。模拟结果表明,PMTO路线的能源效率和CO_(2)排放量分别为55.60%和0.55 t CO_(2)/t烯烃,优于其他3条技术路线。在经济性能上,该路线具有产品成本低(4918.59 CNY/t)和内部收益率高(70.18%)的优势,总净现值是初始投资的5.98倍,且投资回报期为1.87年。因此,PMTO路线是一条可行的商业化技术路径。展开更多
文摘DQPSK modem has been chosen as the modem scheme in many mobile communication systems. A new signal processing technique of π/4-DQPSK modem based on software radio is discussed in this paper. Unlike many other software radio solutions to the subject, we choose a universal digital radio baseband processor operating as the co-processor of DSP. Only the core algorithms for signal processing are implemented with DSP. Thus the computation burden on DSP is reduced significantly. Compared with the traditional ones, the technique mentioned in this paper is more promising and attractive. It is extremely compact and power-efficient, which is often required by a mobile communication system. The implementation of baseband signal processing for π/4-DQPSK modem on this platform is illustrated in detail. Special emphases are laid on the architecture of the system and the algorithms used in the baseband signal processing. Finally, some experimental results are presented and the performances of the signal processing and compensation algorithms are evaluated through computer simulations.
文摘Software Process Workshop (SPW 2005) was held in Beijing on May 25-27, 2005. This paper introduces the motivation of organizing such a workshop, as well as its theme and paper gathering and review; and summarizes the main content and insights of 11 keynote speeches, 30 regular papers in five sessions of “Process Content”, “Process Tools and Metrics”, “Process Management”, “Process Representation and Analysis”, and “Experience Reports”, 8 software development support tools demonstration, and the ending panel “Where Are We Now? Where Should We Go Next?”.
基金supported by the National Natural Science Foundation of China (71671090)the Fundamental Research Funds for the Central Universities (NP2020022)the Qinglan Project of Excellent Youth or Middle-Aged Academic Leaders in Jiangsu Province。
文摘Due to the randomness and time dependence of the factors affecting software reliability, most software reliability models are treated as stochastic processes, and the non-homogeneous Poisson process(NHPP) is the most used one.However, the failure behavior of software does not follow the NHPP in a statistically rigorous manner, and the pure random method might be not enough to describe the software failure behavior. To solve these problems, this paper proposes a new integrated approach that combines stochastic process and grey system theory to describe the failure behavior of software. A grey NHPP software reliability model is put forward in a discrete form, and a grey-based approach for estimating software reliability under the NHPP is proposed as a nonlinear multi-objective programming problem. Finally, four grey NHPP software reliability models are applied to four real datasets, the dynamic R-square and predictive relative error are calculated. Comparing with the original single NHPP software reliability model, it is found that the modeling using the integrated approach has a higher prediction accuracy of software reliability. Therefore, there is the characteristics of grey uncertain information in the NHPP software reliability models, and exploiting the latent grey uncertain information might lead to more accurate software reliability estimation.
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.
基金supported by the National Natural Science Foundation for Youth of China(61802174)the Natural Science Foundation for Youth of Jiangsu Province(BK20181016)+1 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(18KJB520019)the Scientific Research Foundation of Nanjing Institute of Technology of China(YKJ201614)
文摘In order to assure quality and control process in the development of the aircraft collaborative design software, a maturity assessment model is proposed. The requirements designing—house of quality is designed to evaluate the maturity degree of the solution, and the evaluation results can help to manage and control the development process. Furthermore, a fuzzy evaluation method based on the minimum deviation is proposed to deal with the fuzzy information. The quantitative evaluation result of the maturity degree can be calculated by optimizing the semantic discount factor aim for the minimum deviation. Finally, this model is illustrated and analyzed by an example study of the aircraft collaborative design software.
文摘The technologies of software architecture are introduced, and the software analysis-and-design process is divided into requirement analysis, software architecture design and system design. Using these technologies, a model of architecture-centric software analysis and design process（ACSADP） is proposed. Meanwhile, with regard to the completeness, consistency and correctness between the software requirements and design results, the theories of function and process control are applied to ACSADP. Finally, a model of integrated development environnment （IDE） for ACSADP is propcsed. It can be demonstrated by the practice that the model of ACSADP can aid developer to manage software process effectively and improve the quality of software analysis and design.
文摘The simulation of underwater acoustic information flow is an important way to research sonar performance and its engagement effectiveness in the ocean environment.This paper analyzes the significance of modeling an open and sophisticated simulation software architecture by object-oriented method,and introduces the modeling processes and expression method of simulation architecture.According to the requirements of simulation system and the underwater acoustic information flow,the logical architecture of simulation software system is modeled by the object-oriented method.A use-case view captured the system requirements.The logical view shows the logical architecture of software system.The simulation software is decomposed into the loose coupling constituent parts by layering and partitioning the packages for maintainability.The design patterns enabled the simulation software to have good expansibility and reusability.The simulation system involving multi-targets and multi-sonar is developed based on the architecture model.Practices show that the model meets the needs for simulating an open and sophisticated system.
基金Project(10672197) supported by the National Natural Science Foundation of ChinaProject(07JJ1001) supported by the Natural Science Foundation of Hunan Province for Distinguished Young Scholars,China
文摘Mathematical model of filling disk-shaped mold cavity in steady state was studied.And the mathematical model under vibration field was developed from the model in steady state.According to the model of filling disk-shaped mold cavity in steady state,the filling time,the distribution of velocity field and the pressure field were obtained.The analysis results from rheological analytic model were compared with the numerical simulation results using Moldflow software in the powder injection molding filling process.Through the comparison,it is found that it is unreasonable to neglect the influence of temperature when calculated the pressure changing with the time at the cavity gate,while it can be neglected in other situations such as calculating the distribution of the velocity fields.This provides a theoretical reference for the establishment of correct model both in steady state and under vibration force field in the future.
文摘废塑料污染已经成为仅次于气候问题的第二大环境问题,废塑料的数量逐年递增。为了解决废塑料的环境污染问题,设计了废塑料化学升级制烯烃工艺的4条技术路线:废塑料气化经费-托合成制烯烃路线(PFTO),废塑料气化经一步法制烯烃路线(PZTO),废塑料气化经甲醇制烯烃路线(PMTO),废塑料裂解经加氢裂化制烯烃路线(PPTO)。为验证其可行性,对4条技术路线进行了化工流程模拟,采用技术经济性分析方法对比了4条技术路线的能源效率、经济性、CO_(2)排放量和碳原子利用效率等参数。模拟结果表明,PMTO路线的能源效率和CO_(2)排放量分别为55.60%和0.55 t CO_(2)/t烯烃,优于其他3条技术路线。在经济性能上,该路线具有产品成本低(4918.59 CNY/t)和内部收益率高(70.18%)的优势,总净现值是初始投资的5.98倍,且投资回报期为1.87年。因此,PMTO路线是一条可行的商业化技术路径。
