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等离子原位制备VC增强Al_(1.5)CoCrFeNi高熵合金熔覆层的组织与力学性能
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作者 王虎 秦晓婷 +1 位作者 王智慧 贺定勇 《表面技术》 北大核心 2025年第3期110-117,共8页
目的制备不同含量碳化物增强BCC结构的高熵合金熔覆层,研究碳化物含量对其微观组织和力学性能的影响规律。方法在Q235钢表面采用等离子原位合成技术制备Al_(1.5)CoCrFeNi(VC)x(x为0、0.1、0.2、0.3)高熵合金熔覆层,研究VC含量对其物相... 目的制备不同含量碳化物增强BCC结构的高熵合金熔覆层,研究碳化物含量对其微观组织和力学性能的影响规律。方法在Q235钢表面采用等离子原位合成技术制备Al_(1.5)CoCrFeNi(VC)x(x为0、0.1、0.2、0.3)高熵合金熔覆层,研究VC含量对其物相组成、微观组织及力学性能的影响。结果在x=0时,熔覆层为简单体心立方(BCC)固溶体结构,微观组织呈典型的树枝晶,枝晶内为富含Al、Ni的BCC固溶体,枝晶间为富含Cr、Fe的BCC固溶体。在加入V、C后(x为0.1、0.2、0.3),物相组成转变为BCC相、原位合成的VC增强相及少量的σ相。VC呈颗粒状、长条状及十字状,主要偏聚于基体的树枝晶间,少数从枝晶内析出,且随着V、C含量的提高,VC的析出量逐渐上升。TEM结果显示,原位合成的VC增强相与基体之间的界面整洁,无反应物生成。当VC的含量x由0提高至0.3时,熔覆层的硬度由529.3HV增至829.8HV,磨损率由34.88mg/min降至2.45mg/min。在x=0时,熔覆层的磨损形式以微观切削为主,以多次塑性变形为辅;在原位合成VC增强相后(x为0.1、0.3),熔覆层的磨损形式以微观切削为主。结论原位合成VC对高熵合金起到了明显的强化作用,随着VC含量的增加(x为0~0.3),熔覆层的显微硬度和耐磨性逐渐增加。 展开更多
关键词 等离子熔覆 原位合成 高熵合金 vc 微观组织 力学性能
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VC对冻融处理过程中莲子淀粉理化及消化特性变化的影响
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作者 张婉妮 何伟炜 +1 位作者 宋萧萧 殷军艺 《食品科学》 北大核心 2025年第4期44-50,共7页
为明确冻融处理过程中VC的添加对莲子淀粉理化及消化特性的影响,分别采用扫描电子显微镜、傅里叶变换红外光谱、X射线衍射、差示扫描量热仪进行多尺度结构表征,并对其流变特性及体外消化特性进行测定。结果表明,随着冻融次数的增加,凝... 为明确冻融处理过程中VC的添加对莲子淀粉理化及消化特性的影响,分别采用扫描电子显微镜、傅里叶变换红外光谱、X射线衍射、差示扫描量热仪进行多尺度结构表征,并对其流变特性及体外消化特性进行测定。结果表明,随着冻融次数的增加,凝胶孔隙增大且析水率降低,添加VC可以使莲子淀粉在冻融处理中形成更加致密的凝胶,从而降低析水率并提高冻融稳定性。并且随着冻融次数增加,淀粉重结晶程度增强,添加VC会抑制冻融处理后莲子淀粉的消化率,潜在的原因与添加VC会增强莲子淀粉的短程有序及双螺旋结构和相对结晶度等有关。综上,VC能提高莲子淀粉的冻融稳定性,并能降低冻融处理后莲子淀粉的消化率。 展开更多
关键词 莲子淀粉 vc 冻融处理 消化特性
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Linux中Software RAID驱动程序的机制分析 被引量:5
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作者 王沛 韩耀伟 +1 位作者 刘斌 潘金贵 《小型微型计算机系统》 CSCD 北大核心 2001年第3期305-308,共4页
本文简单介绍了 RAID的含义 ,级别分类及其在 L inux中的应用 ,着重探讨了 L inux中 Software RAID驱动程序的体系结构以及 buffer cache的机制 ,并以
关键词 LINUX software RAID 驱动程序 缓冲区 UNIX 操作系统
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Golden Software Voxler在污染场地调查与风险评估方面的应用 被引量:8
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作者 李晓璇 张斌 +3 位作者 万正茂 邹卉 陈辉 戴敏 《科学技术与工程》 北大核心 2017年第8期317-323,共7页
三维绘图软件Golden Software Voxler已广泛应用于地质勘探、水质分析、空气污染监测等方面,而在土壤污染方面的应用较少。根据对某污染场地前期的调查与研究,确定了该场地的土壤关注污染物为重金属镍。运用Voxler 3.0对污染物监测数据... 三维绘图软件Golden Software Voxler已广泛应用于地质勘探、水质分析、空气污染监测等方面,而在土壤污染方面的应用较少。根据对某污染场地前期的调查与研究,确定了该场地的土壤关注污染物为重金属镍。运用Voxler 3.0对污染物监测数据进行处理,绘制污染物的钻孔轨迹图、三向切片图以及体积渲染图。结果显示镍主要集中分布在场地东北部地表以下50~250 cm范围内,浓度随着深度增加而减小且有向下扩散的趋势。Voxler的应用为污染物在土壤中的空间分布提供了可视化表达,从而为后续的风险评估和污染防治工作提供数据支撑。 展开更多
关键词 GOLDEN software Voxler 污染场地 土壤污染 风险评估 污染防治
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高效液相色谱法测定菜用大豆鲜籽粒VC含量 被引量:1
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作者 钟文娟 石盛佳 +3 位作者 陈四维 戢沛城 龚一耘 牟方生 《保鲜与加工》 CAS 北大核心 2024年第2期44-49,共6页
为建立菜用大豆鲜籽粒VC含量的高效液相色谱测定方法,采用30 g/L偏磷酸溶液低温提取样品后,进行高效液相色谱分析,色谱柱为Agilent Eclipse XDB-C18柱(4.6 mm×250 mm×5μm),流动相为1 g/L偏磷酸溶液∶甲醇=96∶4(V/V),流速0.8... 为建立菜用大豆鲜籽粒VC含量的高效液相色谱测定方法,采用30 g/L偏磷酸溶液低温提取样品后,进行高效液相色谱分析,色谱柱为Agilent Eclipse XDB-C18柱(4.6 mm×250 mm×5μm),流动相为1 g/L偏磷酸溶液∶甲醇=96∶4(V/V),流速0.8 mL/min,检测波长243 nm,柱温25℃,以保留时间定性,外标法定量。结果表明:VC质量浓度范围为2~40μg/mL时,其与峰面积呈良好的线性关系(R2=1.000),平均加标回收率为108.14%,相对标准偏差为1.70%。所建立的方法操作简便,灵敏度高,分离度好,结果准确,重复性也比较好,适用于测定菜用大豆鲜籽粒VC含量,为优质菜用大豆的选育和生产提供技术支持。 展开更多
关键词 菜用大豆 vc 高效液相色谱法
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基于Fisher判别分析可分性信息融合的马铃薯VC含量高光谱检测方法 被引量:4
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作者 郭林鸽 殷勇 +1 位作者 于慧春 袁云霞 《食品科学》 EI CAS CSCD 北大核心 2024年第7期164-171,共8页
为提高马铃薯VC含量检测结果的准确性和可靠性,提出一种基于Fisher判别分析(Fisher discriminant analysis,FDA)可分性数据融合的检测模型输入变量构建方法。首先,利用高光谱成像技术采集200个马铃薯的高光谱信息,通过对比6种预处理方... 为提高马铃薯VC含量检测结果的准确性和可靠性,提出一种基于Fisher判别分析(Fisher discriminant analysis,FDA)可分性数据融合的检测模型输入变量构建方法。首先,利用高光谱成像技术采集200个马铃薯的高光谱信息,通过对比6种预处理方法和原始数据的建模结果,确定多元散射校正为光谱数据的预处理方法;其次,采用竞争性自适应重加权采样(competitive adaptive reweighted sampling,CARS)、连续投影算法(successive projections algorithm,SPA)及CARS-SPA组合算法3种方法提取相应特征波长,通过对比分析最终确定34个有效特征波长;然后,将有效特征波长进行FDA可分性数据融合,根据融合的新变量对样本间差异性判别能力的大小进行筛选,确定构建检测模型的输入变量;最后,分别对FDA融合前后筛选的变量建立偏最小二乘模型和反向传播神经网络(back propagation neural network,BPNN)模型,并对检测结果进行对比分析。结果表明,将CARS算法提取的34个特征波长进行FDA融合,采用前3个融合变量作为构建检测模型的输入变量时,其所建BPNN模型的相关系数由0.9726提高至0.9990,均方根误差由0.7723降低至0.1727,不仅能够极大地降低数据分析维度,而且能够提高检测结果的准确性。因此,基于FDA可分性数据融合构建检测模型输入变量可以提高马铃薯VC含量检测结果的准确性。 展开更多
关键词 高光谱成像 FISHER判别分析 马铃薯 vc含量检测 模型
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Software Agent间的知识级通信 被引量:1
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作者 徐鹏 高济 《计算机工程》 CAS CSCD 北大核心 1999年第8期29-29,53,共2页
提供了一种综合了概念表示语言(CRLE)、共享本体论、消息表示语言(MRL)和通信促进器的共享信息和知识的高层模型,以实现SoftwareAgent间的知识级通信。
关键词 software AGENT 本体论 知识级通信 人工智能
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On modeling approach for embedded real-time software simulation testing 被引量:6
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作者 Yin Yongfeng Liu Bin Zhong Deming Jiang Tongmin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期420-426,共7页
Modeling technology has been introduced into software testing field. However, how to carry through the testing modeling effectively is still a difficulty. Based on combination of simulation modeling technology and emb... Modeling technology has been introduced into software testing field. However, how to carry through the testing modeling effectively is still a difficulty. Based on combination of simulation modeling technology and embedded real-time software testing method, the process of simulation testing modeling is studied first. And then, the supporting environment of simulation testing modeling is put forward. Furthermore, an approach of embedded real-time software simulation testing modeling including modeling of cross-linked equipments of system under testing (SUT), test case, testing scheduling, and testing system service is brought forward. Finally, the formalized description and execution system of testing models are given, with which we can realize real-time, closed loop, mad automated system testing for embedded real-time software. 展开更多
关键词 embedded real-time software software testing testing modeling SIMULATION
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Optimal hardware/software co-synthesis for core-based SoC desi gns 被引量:5
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作者 Zhan Jinyu Xiong Guangze 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期402-409,共8页
A hardware/software co-synthesis method is presented for SoC designs consisting of both hardware IP cores and software components on a graph-theoretic formulation. Given a SoC integrated with a set of functions and a ... A hardware/software co-synthesis method is presented for SoC designs consisting of both hardware IP cores and software components on a graph-theoretic formulation. Given a SoC integrated with a set of functions and a set of performance factors, a core for each function is selected from a set of alternative IP cores and software components, and optimal partitions is found in a way to evenly balance the performance factors and to ultimately reduce the overall cost, size, power consumption and runtime of the core-based SoC. The algorithm formulates IP cores and components into the corresponding mathematical models, presents a graph-theoretic model for finding the optimal partitions of SoC design and transforms SoC hardware/software co-synthesis problem into finding optimal paths in a weighted, directed graph. Overcoming the three main deficiencies of the traditional methods, this method can work automatically, evaluate more performance factors at the same time and meet the particularity of SoC designs. At last, the approach is illustrated that is practical and effective through partitioning a practical system. 展开更多
关键词 SOC co-synthesis partition IP core software component optimal path.
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Design and realization of synchronization circuit for GPS software receiver based on FPGA 被引量:5
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作者 Xiaolei Yu Yongrong Sun +1 位作者 Jianye Liu Jianfeng Miao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期20-26,共7页
With research on the carrier phase synchronization and symbol synchronization algorithm of demodulation module, a synchronization circuit system is designed for GPS software receiver based on field programmable gate a... With research on the carrier phase synchronization and symbol synchronization algorithm of demodulation module, a synchronization circuit system is designed for GPS software receiver based on field programmable gate array (FPGA), and a series of experiment is done on the hardware platform. The result shows the all-digital synchronization and demodulation of GPS intermediate frequency (IF) signal can be realized and applied in embedded real-time GPS software receiver system. It is verified that the decision-directed joint tracking algorithm of carrier phase and symbol timing for received signals from GPS is reasonable. In addition, the loop works steadily and can be used for receiving GPS signals using synchronous demodulation. The synchronization circuit for GPS software receiver designed based on FPGA has the features of low cost, miniaturization, low power and real-time. Surely, it will become one of the development directions for GPS and even GNSS embedded real-time software receiver. 展开更多
关键词 software receiver synchronization circuit field programmable gate army GPS joint tracking algorithm.
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A New Signal Processing Technique of π/4-DQPSK Modem Based on Software Radio 被引量:3
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作者 Chang Jiang & Zhang Naitong Communication Research Center, Harbin Institute of Technology, Harbin 150001, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期20-24,共5页
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
关键词 DQPSK Baseband signal processing DSP software radio.
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Automatic software fault localization based on artificial bee colony 被引量:2
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作者 Linzhi Huang Jun Ai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第6期1325-1332,共8页
Software debugging accounts for a vast majority of the financial and time costs in software developing and maintenance. Thus, approaches of software fault localization that can help automate the debugging process have... Software debugging accounts for a vast majority of the financial and time costs in software developing and maintenance. Thus, approaches of software fault localization that can help automate the debugging process have become a hot topic in the field of software engineering. Given the great demand for software fault localization, an approach based on the artificial bee colony (ABC) algorithm is proposed to be integrated with other related techniques. In this process, the source program is initially instrumented after analyzing the dependence information. The test case sets are then compiled and run on the instrumented program, and execution results are input to the ABC algorithm. The algorithm can determine the largest fitness value and best food source by calculating the average fitness of the employed bees in the iteralive process. The program unit with the highest suspicion score corresponding to the best test case set is regarded as the final fault localization. Experiments are conducted with the TCAS program in the Siemens suite. Results demonstrate that the proposed fault localization method is effective and efficient. The ABC algorithm can efficiently avoid the local optimum, and ensure the validity of the fault location to a larger extent. 展开更多
关键词 software debugging software fault localization arti-ficial bee colony (ABC) algorithm program instrumentation.
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Maturity assessment model for aircraft collaborative design software solution 被引量:5
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作者 HUO Ying QIU Peng ZHAI Jiyou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1228-1236,共9页
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
关键词 aircraft collaborative design software development process quality function deployment fuzzy evaluation method
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Real-time embedded software testing method based on extended finite state machine 被引量:6
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作者 Yongfeng Yin Bin Liu Hongying Ni 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期276-285,共10页
The reliability of real-time embedded software directly determines the reliability of the whole real-time embedded sys- tem, and the effective software testing is an important way to ensure software quality and reliab... The reliability of real-time embedded software directly determines the reliability of the whole real-time embedded sys- tem, and the effective software testing is an important way to ensure software quality and reliability. Based on the analysis of the characteristics of real-time embedded software, the formal method is introduced into the real-time embedded software testing field and the real-time extended finite state machine (RT-EFSM) model is studied firstly. Then, the time zone division method of real-time embedded system is presented and the definition and description methods of time-constrained transition equivalence class (timeCTEC) are presented. Furthermore, the approaches of the testing sequence and test case generation are put forward. Finally, the proposed method is applied to a typical avionics real- time embedded software testing practice and the examples of the timeCTEC, testing sequences and test cases are given. With the analysis of the testing result, the application verification shows that the proposed method can effectively describe the real-time embedded software state transition characteristics and real-time requirements and play the advantages of the formal methods in accuracy, effectiveness and the automation supporting. Combined with the testing platform, the real-time, closed loop and automated simulation testing for real-time embedded software can be realized effectively. 展开更多
关键词 real-time system real-time embedded software for- mal method extended finite state machine (EFSM) testing se- quence test case.
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Incorporating S-shaped testing-effort functions into NHPP software reliability model with imperfect debugging 被引量:7
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作者 Qiuying Li Haifeng Li Minyan Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期190-207,共18页
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
关键词 testing-effort(TE) imperfect debugging(ID) software reliability growth models(SRGMs) S-shaped non-homogeneous Poisson process(NHPP)
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Design of BPS digital frontend for software defined radio receiver 被引量:2
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作者 王洪梅 KIM Jae-hyung +2 位作者 王法广 LEE Sang-hyuk 王雪松 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4709-4716,共8页
In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is ... In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is designed.In order to increase the processing speed,Gigabit Ethernet was applied in the platform at speed of 5×10~8 bit/s.By appropriate design of interpolant according to the position of input RF signals,multi-band receiving can be realized in the platform with suppression more than 35 d B without changing hardware. 展开更多
关键词 software defined radio(SDR) digital frontend bandpass sampling
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Web software reliability modeling with random impulsive shocks 被引量:1
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作者 Jianfeng Yang Ming Zhao Wensheng Hu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期349-356,共8页
As the web-server based business is rapidly developed and popularized, how to evaluate and improve the reliability of web-servers has been extremely important. Although a large num- ber of software reliability growth ... As the web-server based business is rapidly developed and popularized, how to evaluate and improve the reliability of web-servers has been extremely important. Although a large num- ber of software reliability growth models (SRGMs), including those combined with multiple change-points (CPs), have been available, these conventional SRGMs cannot be directly applied to web soft- ware reliability analysis because of the complex web operational profile. To characterize the web operational profile precisely, it should be realized that the workload of a web server is normally non-homogeneous and often observed with the pattern of random impulsive shocks. A web software reliability model with random im- pulsive shocks and its statistical analysis method are developed. In the proposed model, the web server workload is characterized by a geometric Brownian motion process. Based on a real data set from IIS server logs of ICRMS website (www.icrms.cn), the proposed model is demonstrated to be powerful for estimating impulsive shocks and web software reliability. 展开更多
关键词 web software software reliability growth model(SRGM) change-point (CP) impulsive shocks geometric Brown-ian motion.
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NHPP-based software reliability model considering testing effort and multivariate fault detection rate 被引量:4
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作者 Jie Zhang Yang Lu +1 位作者 Shu Yang Chong Xu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期260-270,共11页
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
关键词 software reliability software reliability growth mo del(SRGM) testing effort fault detection rate(FDR).
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WC–xVC复合粉的制备及高含量VC对WC–Co基硬质合金微观结构和力学性能的影响 被引量:1
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作者 邓孝纯 康笑东 张国华 《粉末冶金技术》 CAS CSCD 北大核心 2024年第3期226-233,254,共9页
采用两步碳热还原法合成了WC–xVC复合粉,并以此为原料通过真空烧结法制备了不同Co含量(6%和10%,质量分数)的WC–Co–VC硬质合金,研究了烧结温度(1420℃、1440℃和1460℃)对硬质合金致密化过程的影响,分析了Co和VC含量对WC晶粒尺寸以及... 采用两步碳热还原法合成了WC–xVC复合粉,并以此为原料通过真空烧结法制备了不同Co含量(6%和10%,质量分数)的WC–Co–VC硬质合金,研究了烧结温度(1420℃、1440℃和1460℃)对硬质合金致密化过程的影响,分析了Co和VC含量对WC晶粒尺寸以及硬质合金维氏硬度和断裂韧性的影响。结果表明,随着烧结温度的升高,合金的相对密度增大,当烧结温度为1460℃时,所有合金试样的相对密度均大于98.5%。此外,随着VC含量的增加,WC的平均晶粒尺寸减小,这导致样品的硬度提高,断裂韧性降低。当VC质量分数为6%时,WC–6Co硬质合金和WC–10Co硬质合金的硬度均达到最大值,分别为HV301941和HV301838。在烧结温度和VC含量一定的情况下,试样的断裂韧性随着Co含量的增加而增加,试样的硬度随着Co含量的增加而减小。 展开更多
关键词 WC–vc复合粉 WC–Co硬质合金 维氏硬度 断裂韧性 CO含量
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RFC:a feature selection algorithm for software defect prediction 被引量:2
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作者 XU Xiaolong CHEN Wen WANG Xinheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期389-398,共10页
Software defect prediction(SDP)is used to perform the statistical analysis of historical defect data to find out the distribution rule of historical defects,so as to effectively predict defects in the new software.How... Software defect prediction(SDP)is used to perform the statistical analysis of historical defect data to find out the distribution rule of historical defects,so as to effectively predict defects in the new software.However,there are redundant and irrelevant features in the software defect datasets affecting the performance of defect predictors.In order to identify and remove the redundant and irrelevant features in software defect datasets,we propose ReliefF-based clustering(RFC),a clusterbased feature selection algorithm.Then,the correlation between features is calculated based on the symmetric uncertainty.According to the correlation degree,RFC partitions features into k clusters based on the k-medoids algorithm,and finally selects the representative features from each cluster to form the final feature subset.In the experiments,we compare the proposed RFC with classical feature selection algorithms on nine National Aeronautics and Space Administration(NASA)software defect prediction datasets in terms of area under curve(AUC)and Fvalue.The experimental results show that RFC can effectively improve the performance of SDP. 展开更多
关键词 software defect prediction(SDP) feature selection CLUSTER
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