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Optimization Algorithms of PERT/cpm Network Diagrams in Linear Diophantine Fuzzy Environment

Computer Modeling in Engineering & Sciences 2024年第4期139卷 1095-1118页

作者： Mani Parimala Karthikeyan Prakash Ashraf Al-Quran Muhammad Riaz Saeid Jafari Department of Mathematics Bannari Amman Institute of TechnologySathyamangalamTamil Nadu638401India Basic Sciences Department Preparatory Year DeanshipKing Faisal UniversityAl-Ahsa31982Saudi Arabia Department of Mathematics University of the PunjabLahorePakistan College of Vestsjaelland South Herrestraede 11Slagelse4200Denmark

The idea of linear Diophantine fuzzy set(LDFS)theory with its control parameters is a strong model for machine learning and optimization under uncertainty.The activity times in the critical path method(cpm)representation procedures approach are initially static,but in the Project Evaluation and Review Technique(PERT)approach,they are probabilistic.This study proposes a novel way of project review and assessment methodology for a project network in a linear Diophantine fuzzy(LDF)environment.The LDF expected task time,LDF variance,LDF critical path,and LDF total expected time for determining the project network are all computed using LDF numbers as the time of each activity in the project network.The primary premise of the LDF-PERT approach is to address ambiguities in project network activity timesmore simply than other approaches such as conventional PERT,Fuzzy PERT,and so on.The LDF-PERT is an efficient approach to analyzing symmetries in fuzzy control systems to seek an optimal decision.We also present a new approach for locating LDF-cpm in a project network with uncertain and erroneous activity timings.When the available resources and activity times are imprecise and unpredictable,this strategy can help decision-makers make better judgments in a project.A comparison analysis of the proposed technique with the existing techniques has also been discussed.The suggested techniques are demonstrated with two suitable numerical examples.

关键词： Linear Diophantine fuzzy graphs project management PERT cpm linear Diophantine fuzzy numbers score function accuracy function

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Network Analysis for Projects with High Risk Levels in Uncertain Environments

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Computers, Materials & Continua 2022年第1期70卷 1281-1296页

作者： Mohamed Abdel-Basset Asmaa Atef Mohamed Abouhawwash Yunyoung Nam Nabil M.AbdelAziz Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

The critical path method is one of the oldest and most important techniques used for planning and scheduling projects.The main objective of project management science is to determine the critical path through a network representation of projects.The critical path through a network can be determined by many algorithms and is useful for managing,monitoring,and controlling the time and cost of an entire project.The essential problem in this case is that activity durations are uncertain;time presents considerable uncertainty because the time of an activity is not always easily or accurately estimated.This issue increases the need to use neutrosophic theory to solve the critical path problem.Real-world problems are characterized by a lack of precision,consistency,and completeness.The concept of neutrosophic sets has been introduced as a generalization of fuzzy,intuitionistic fuzzy,and crisp sets to overcome the ambiguity surrounding real-world problems.Truth-,falsity-,and indeterminacy-membership functions are used to express neutrosophic elements.This study was performed to examine a neutrosophic event-oriented algorithm for determining the critical path in activity-on-arc networks.The activity time estimates are presented as trapezoidal neutrosophic numbers,and score and accuracy functions are used to obtain a crisp model of the problem.An appropriate numerical example is then used to explain the proposed method.

关键词： Project management project life cycle project planning project scheduling cpm neutrosophic set theory trapezoidal neutrosophic number

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第18届国际植物检疫措施委员会通过了4项国际标准

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植物检疫 2024年第3期38卷 33-33页

作者：孙双艳海关总署国际检验检疫标准与技术法规研究中心

2024年4月15-19日,第18届国际植物检疫措施委员会(cpm)在罗马召开,会议通过了4项国际植物检疫措施标准:包括第5号国际植检措施标准《植物检疫术语表》(2022年修订)、第37号国际植检措施标准附件《实蝇寄主状态的确定(实蝇科Tephritidae)... 详细信息

2024年4月15-19日,第18届国际植物检疫措施委员会(cpm)在罗马召开,会议通过了4项国际植物检疫措施标准:包括第5号国际植检措施标准《植物检疫术语表》(2022年修订)、第37号国际植检措施标准附件《实蝇寄主状态的确定(实蝇科Tephritidae)(修订)》、第4号国际植检措施标准《建立非疫区的要求》、第28号国际植检措施标准附件《柑橘上苹果异形小卷蛾的冷处理》。国际植物检疫措施标准是一系列旨在保护全球农业免受有害生物侵害的指导原则和标准,是由世界级专家制定并在cpm会议上通过的。本次会议通过的这4项标准是各国在植物和植物产品贸易中应用的基准,以更好地管理和应对有害生物的威胁或存在。

关键词：植物检疫措施有害生物植检非疫区实蝇国际植物检疫措施标准冷处理 cpm

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Reduced-state noncoherent MLSD method for cpm in aeronautical telemetry

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The Journal of China Universities of Posts and Telecommunications 2020年第4期27卷 43-53页

作者： Zhou You Duan Ruifeng Jiang Bofeng School of Electoric and Information Engineering Beihang UniversityBeijing 100191China School of Information Science and Technology Beijing Forestry UniversityBeijing 100083China Beijing Xinwei Technology Group.Co. LtdBeijing 100193China

Due to high spectral efficiency and power efficiency, the continuous phase modulation(cpm) technique with constant envelop is widely used in range telemetry. How to improve the bit error rate(BER) performance of cpm and keep a reasonable computational complexity is the key of the entire telemetry system and the focus of research and engineering design. In this paper, a reduced-state noncoherent maximum likelihood sequence detection(MLSD) method for cpm is proposed. In the proposed method, the criterion of noncoherent MLSD is derived for cpm when the carrier phase is unknown. A novel Viterbi algorithm(VA) with modified state vector is designed to simplify the implementation of noncoherent MLSD. Both analysis and numerical results show that the proposed method reduces the computational complexity significantly and does not need accurate carrier phase recovery, which overcomes the shortage of traditional MLSD method. Additionally, the proposed method exceeds the traditional MLSD method when carrier phase deviation exists.

关键词： cpm low-complexity noncoherent detection MLSD Viterbi algorithm

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Confidential Procedure Model：a Method for Quantifying Confidentiality Leakage

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China Communications 2012年第11期9卷 117-126页

作者： Zhang Yong Li Xiangxue Zhou Yuan Li Zhibin Qian Haifeng Department of Computer Science and Technology East China Normal University Shanghai 200241 P. R. China State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 P. R. China National Computer Network Emergency Response Technical Team (Coordination Center of China) Beijing 100029 P. R. China.

In this paper, we propose a theoretical-information Confidential Procedure Model (cpm) to quantify confidentiality (or information leakage). The advantages of the cpm model include the following: 1) confidentiality loss is formalized as a dynamic procedure, instead of a static function, and described via the "waterfall" diagram; 2) confidentiality loss is quantified in a relative manner, i.e., taken as a quantitative metric, the ratio of the conditional entropy being reserved after observing the entropy of the original full confidential information; 3) the optimal attacks including exhaustive attacks as well as all possible attacks that have (or have not even) been discovered, are taken into account when defining the novel concept of the confidential degree. To elucidate the proposed model, we analyze the information leakage in side-channel attacks and the anonymity of DC-net in a quantitative manner.

关键词：信息保密程序模型信息泄漏量化穷举攻击保密性信息泄露 cpm

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Non-Coherent Multi-Symbol Detection of PR-cpm for Deep Space Relay Satellites with Physical-Layer Network Coding

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China Communications 2020年第7期17卷 101-112页

作者： Meng Wang Chongzheng Hao Xiaoyu Dang Xiangbin Yu College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The demand for wireless spectrum and data transmission has increased dramatically with the rapid growth of deepspace exploration and communication.The satellite relay communication is an essential technique to solve the issues above.The method of combining Physical-layer Network Coding(PNC)with Continuous Phase Modulation(cpm)on relay satellites can improve communication efficiency and perform the collection and transmission of space data effectively.Partial-Response cpm(PR-cpm)signals possess excellent spectrum and power characteristics and are suitable for deep-space communications with limited bandwidth and massive data transmission.In this paper,a partial response non-coherent multi-symbol detection algorithm is proposed based on the Maximum-Likelihood principle.The proposed algorithm fully utilizes the memory properties of PR-cpm signals and makes decisions on specified symbols by observing a number of symbols each time.Simulation results indicate that the performance gain under the Bit Error Rate of 10-4 is about 2 dB when 5 symbols are inspected,compared with the case where the observation length is 3.

关键词： communication cpm Symbol

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A 40-GHz Colliding Pulse Mode-Locked Semiconductor Laser

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Chinese Physics Letters 2016年第6期33卷 37-40页

作者：刘松涛张瑞康陆丹阚强王圩吉晨 Key Laboratory of Semiconductor Materials Science Institute of Semiconductorsand Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesChinese Academy of Sciences

A monolithically active-passive integrated colliding pulse mode-locked semiconductor laser is demonstrated in the InGaAsP//InP material system. The device is mode locked at the second harmonic passive mode-locking regime with a wide mode-locking range. Pulse trains with the repetition rate of 40 GHz, 3-dB rf line width of 25 kHz, the pulse width of 2.5 ps, and a nearly transform-limited time-bandwidth product of 0.53 are obtained.

关键词： mode as of InP A 40-GHz Colliding Pulse Mode-Locked Semiconductor Laser GHz cpm in TBP

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Numerical study of three phase shifts and dual corrugation pitch modulated(cpm) DFB semiconductor lasers based on reconstruction equivalent chirp technology

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Chinese Science Bulletin 2010年第35期55卷 4083-4088页

作者： SHI YueChun TU XingHua LI SiMin ZHOU YaTing JIA LingHui CHEN XiangFei Microwave-Photonics Technology Laboratory National Laboratory of Microstructures Nanjing University Nanfing 210093 China Department of Electronic Science and Engineering Nanjing University Nanjing 210093 China Microfluidics and Optics Technology Research Center College of Opto-Electronic Engineering Nanjing University of Posts and Telecommunication Nanfing 210003 China

A distributed feedback(DFB) semiconductor laser with three phase shifts based on reconstruction equivalent chirp(REC) technology is proposed and investigated numerically.With the combination of multiple phase shifts and corrugation pitch modulated(cpm) structure,we also propose a novel and more complex structure named dual cpm,which has a flatter light power distribution along the laser cavity compared with the true double phase shifts DFB laser diode(LD),while the P-I curves are nearly the same.The proposed dual cpm structure is also designed and analyzed based on REC technology.The simulation results show that,the DFB semiconductor laser with complex structure such as phase shifts,or even arbitrary variation of the grating period can be achieved equivalently and easily by changing the sampling structure.But its external characteristics are almost the same as those DFB lasers with true phase shifts,or true arbitrary variation of the grating period.The key advantage of the REC technology is that it varies only the sampling structure and keeps the seed grating(actual grating in sampling structure) period constant.So its fabrication needs only low-cost and standard holographic exposure technology.Therefore we believe this method can achieve the high-end and low-cost DFB LD for mass production.

关键词：半导体激光器等效采样拍摄技术数值研究 cpm 啁啾重构基础

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Generation of ultrashort optical pulse by colliding-pulse mode locking in semiconductor laser diodes

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Chinese Science Bulletin 1996年第20期41卷 1755-1760页

作者：孙洪波胡礼中安海岩李玉东刘式墉 State Key Laboratory of Integrated Optoelectronics Jilin University Region Changchun 130023 China

The technique of mode locking has been improved and advanced cosiderably since its first demonstration in 1964. Picosecond, even femtosecond optical pulse is, in principle,capable of being generated easily by the technique.Ultrashort optical pulses from semiconductor laser diodes play an essential role in the research of transient process of high-speed physics phenomenon and molecular relaxation. Interest in picosecond technique has recently been stimulated especially by the applications such as high bit rate time-division multiplexed communication, electrooptic sampling, and picosecond optical logic gate. A considerable amount of theoretical and experimental work has been done on the research.Mode-locking, Q-switching and gain switching are commonly used

关键词： ultrashort optical pulse cpm repetition rate.

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面向cpm的Polar码迭代译码技术研究

面向CPM的Polar码迭代译码技术研究

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作者：窦为龙浙江大学

学位级别：硕士

信道编译码技术是提高通信系统可靠性的关键技术,极化码作为5G（The 5th generation mobile networks）标准中控制信道的编码方案,其纠错能力影响着通信传输的质量。在实际应用中,利用信道编译码来提高系统的纠错性能和抗干扰性能尤为... 详细信息

信道编译码技术是提高通信系统可靠性的关键技术,极化码作为5G（The 5th generation mobile networks）标准中控制信道的编码方案,其纠错能力影响着通信传输的质量。在实际应用中,利用信道编译码来提高系统的纠错性能和抗干扰性能尤为重要。迭代译码技术是一种可以提高译码纠错能力的关键技术。为了进一步提高通信传输的可靠性,本文对极化码迭代译码相关技术展开了研究。首先,本文介绍了极化码的基本原理,包括信道的极化原理和极化码的构造算法。然后,介绍了非系统极化码和系统极化码的编码过程。面向极化码的译码算法,介绍了连续删除译码（Successive Cancellation,SC）和连续删除列表译码（Successive Cancellation List,SCL）两种输出为硬判决的译码算法,以及置信度传播（Belief Propagation,BP）和软消除（Soft Cancellation,SCAN）两种输出为软信息译码算法。最后介绍了连续相位调制（Continuous Phase Modulation,cpm）技术,着重介绍了cpm的基本原理和Rimold分解模型以及cpm的解调算法。其次,针对串行级联cpm方案应用场景中,前向纠错码和cpm相结合可以获得高纠错性能增益的优势,提出了一种基于极化码的cpm串行级联方案。通过将cpm中的Bahl-Cocke-Jelinek-Raviv（BCJR）解调算法与极化码中的SCL-BP译码算法相结合,并在该方案中对极化码的迭代译码算法在软信息传播处理方面进行了改进,通过形成cpm解调与极化码译码的迭代结构,从而最大化极化码的译码增益。通过仿真验证,所提出的串行级联方案在短码长条件下的纠错性能优于基于低密度奇偶校验码（Low Density Parity Check,LDPC）和Turbo码的cpm串行级联方案。最后,针对多编码块传输的应用场景,提出了一种基于关键集合的空间耦合极化码译码方法。通过将关键集合SCL译码算法与空间耦合技术相结合,并在译码时利用对数似然比绝对值准则对关键集合进行排序,从而实现提高译码性能的同时降低译码复杂度。最后将其应用在cpm串行级联方案中,通过仿真验证,该方案能够极大提升多编码块传输误码性能。

关键词：极化码 cpm 迭代译码空间耦合关键集合

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