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Dynamic Bandwidth Allocation and Rate Coordination for DiffServ Environment

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 248-252页

作者： CHEN Gang WU guo-xin ZHANG San-feng YOU feng-qin Department of Computer Science and Engineering Southeast University Nanjing 210096 Jiangsu China Key Laboratory of Computer Network and Information Integration of MOE Southeast University Nanjing 210096Jiangsu China

This paper presents a novel model for dynamic bandwidth allocation and rate coordination based on DiffServ and a bandwidth broker（BB）. In this model, assignment of bandwidth was made according to a periodic trace of network characteristics per application. And adjustment of transfer rate was accomplished through negotiation with applications by a bandwidth agent. This model was evaluated using network simulator 2 （NS-2）, and distinct improvements were found in respects of delay and packet loss of overall network and single flow. Finally, the model was suggested to be leveraged to multimedia applications with properties of lower delay and lower packet loss.

关键词： QoS bandwidth broker(BB) dynamic bandwidth allocation rate coordination

Structural reliability analysis using enhanced cuckoo search algorithm and artificial neural network

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Journal of Systems Engineering and Electronics 2018年第6期29卷 1317-1326页

作者： qin Qiang feng Yunwen LI feng Aerospace Science and Industry Corporation Defense Technology Research and Test Center Beijing 100854China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China CASIC Space Engineering Development Co. LtdBeijing 100854China

The present study proposed an enhanced cuckoo search(ECS) algorithm combined with artificial neural network(ANN) as the surrogate model to solve structural reliability problems. In order to enhance the accuracy and convergence rate of the original cuckoo search(CS) algorithm, the main parameters namely, abandon probability of worst nests paand search step sizeα0 are dynamically adjusted via nonlinear control equations. In addition, a global-best guided equation incorporating the information of global best nest is introduced to the ECS to enhance its exploitation. Then, the proposed ECS is linked to the well-trained ANN model for structural reliability analysis. The computational capability of the proposed algorithm is validated using five typical structural reliability problems and an engineering application. The comparison results show the efficiency and accuracy of the proposed algorithm.

关键词： structural reliability enhanced cuckoo search(ECS) artificial neural network(ANN) cuckoo search(CS) algorithm

新冠肺炎对实习/见习护生负性情绪影响的调查分析

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泰州职业技术学院学报 2020年第1期20卷 148-151页

作者：邹莉石丹周丽娟冯国琴苏丽丽泰州市人民医院江苏泰州225300

目的了解新冠肺炎居家隔离期间护理实习生和见习生的情绪反应现况,并进行影响因素分析,为突发公共卫生事件中护理实习生和见习生心理指导提供依据。方法采用便利抽样法选取我院240名实习和见习护生为研究对象,以一般情况调查表和突发性... 详细信息

目的了解新冠肺炎居家隔离期间护理实习生和见习生的情绪反应现况,并进行影响因素分析,为突发公共卫生事件中护理实习生和见习生心理指导提供依据。方法采用便利抽样法选取我院240名实习和见习护生为研究对象,以一般情况调查表和突发性公共卫生事件问卷进行调查,应用单因素方差分析探索护生情绪反应的影响因素。结果护生负性情绪较为明显,以恐惧最为突出。女生负性情绪得分高于男生(t=-5.620,P<0.01);大专生负性情绪得分高于本科生(t=-8.951,P<0.01);实习生负性情绪得分高于见习生(t=-5.778,P<0.01)。结论突发公共卫生事件下实习护生和见习护生负性情绪较为明显,学校和医院应多渠道尽快了解实习/见习护生的心理状况,及时给予心理评估与指导,医院、高校应着力于改善实习/见习护生就业态度及职业认同感,及时采取相应的心理干预措施。

关键词：新冠肺炎实习/见习护生负性情绪

防隔水煤柱定向爆破应力转移机理及参数优化设计

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河南理工大学学报（自然科学版） 2025年第1期44卷 1-9页

作者：刘少伟郭泽政冯超牛帅河南理工大学能源科学与工程学院河南焦作454000 煤炭安全生产与清洁高效利用省部共建协同创新中心河南焦作454000 安阳工学院土木与建筑工程学院河南安阳455000

目的针对内部存在断层的防隔水煤柱在采动影响下应力场持续变化对其稳定性和工作面安全开采造成极大威胁的问题,方法以鹤壁中泰矿业有限公司3309工作面为工程地质背景,采用理论分析、正交试验和FLAC3D数值模拟试验,研究定向爆破应力转... 详细信息

目的针对内部存在断层的防隔水煤柱在采动影响下应力场持续变化对其稳定性和工作面安全开采造成极大威胁的问题,方法以鹤壁中泰矿业有限公司3309工作面为工程地质背景,采用理论分析、正交试验和FLAC3D数值模拟试验,研究定向爆破应力转移保护防隔水煤柱的影响因素以及不同切顶深度和切顶角度下防隔水煤柱内部应力分布特征。结果结果表明:随着切顶角度和切顶深度增加,垂直应力集中区逐渐向深部转移,但当切顶深度和切顶角度达到一定数值后,继续增加切顶角度或切顶深度对应力集中区位置及垂直应力峰值影响不再明显,对比不同方案防隔水煤柱内部测线数据可知,当切顶深度为15 m、切顶角度为15°时,应力集中区距回风巷距离最远,最远距离为19.76 m,应力峰值最小,最小值为15.65 MPa。结论采用定向爆破技术可以实现切顶卸压应力转移,能够阻断回风巷上覆岩层与防隔水煤柱周边岩层的联系,将防隔水煤柱靠近回风巷一侧应力向深部转移,以减少采动对防隔水煤柱的影响;现场工业性试验结果验证了选定方案切顶深度15 m、切顶角度15°的合理性,防隔水煤柱内部实现了应力转移,选定方案的成功应用有效提高了防隔水煤柱的稳定性,能够满足安全生产要求。研究结果可为类似地质条件下内部存在断层的防隔水煤柱的应力转移保护提供参考依据。

关键词：定向爆破应力转移断层数值模拟防隔水煤柱正交试验

Husimi Function of Excited Squeezed Vacuum State

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Communications in Theoretical Physics 2008年第5期49卷 1305-1309页

作者： guo qin Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics Jiangxi Normal University Nanchang 330022 China

The q-p phase-space distribution function is a popular tool to study semiclassical physics and to describe the quantum aspects of a system. In this paper by using the pure state density operator formula of the Husimi operator Δh（q,p;κ） = [p,q〉κκ〈p,q｜ we deduce the Husimi function of the excited squeezed vacuum state. Then we study the behavior of Husimi distribution graphically.

关键词： the excited squeezed vacuum state Husimi function Husimi operator

Dissolution characteristics of black aluminum dross in Na_(3)AIF_(6)-AIF_(3)-Al_(2)O_(3)molten salt system

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Rare Metals 2023年第8期42卷 2747-2756页

作者： Zheng-Ping Zuo guo-qing Yu Chun-Li Liu Gui-Cheng Liu feng-qin Liu State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China Research Center Heavy Machinery Ministry of Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Physics and Oxide Research Center Hankuk University of Foreign StudiesYongin 17035Republic of Korea School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China Department of Physics Dongguk UniversitySeoul 04620Korea

The dissolution performance of black aluminum dross(BAD)in cryolite electrolyte is key to its recovery by molten salt *** stable operation of the electrolyzer depends mainly on the rapid dissolution of BAD in Na_(3)AlF_(6)-AlF_(3)-Al_(2)O_(3)electrolyte *** this paper,the dissolution performance and behavior of BAD and its main components in the cryolite system were studied,and the saturation solubility of aluminum nitride in this system was *** dissolution performance of BAD in cryolite electrolyte before and after denitration was compared,and the effects of temperature,cryolite ratio,and the doping ratio of BAD and alumina on the dissolution rate were *** obtained results showed that aluminum nitride was the main factor affecting the dissolution performance of BAD in the *** nitride was partly converted toα-Al_(2)O_(3)after addition to the electrolyte,and the convertedα-Al_(2)O_(3)was partially dissolved in the cryolite electrolyte,while the remaining precipitated and accumulated at the bottom with aluminum *** nitride was almost insoluble in the cryolite electrolyte,with 0.0022%solubility.A higher proportion ofα-Al_(2)O_(3)in BAD was negatively influenced its solubility in the cryolite *** dissolution rate of BAD in cryolite electrolytes was effectively improved by mixing BAD withγ-Al_(2)O_(3).

关键词： Aluminum dross Aluminum nitride Kinetics Hydrolysis Dissolution rate

Design Change Model for Effective Scheduling Change Propagation Paths

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1081-1090页

作者： Hai-Zhu Zhang guo-Fu Ding Rong Li Sheng-feng qin Kai-Yin Yan School of Mechanical Engineering Southwest Jiaotong University Northumbria School of Design Northumbria University

Changes in requirements may result in the increasing of product development project cost and lead time, therefore, it is important to understand how require- ment changes propagate in the design of complex product systems and be able to select best options to guide design. Currently, a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally. A new design change model is presented to systematically analyze and search change propagation paths. Firstly, a PDS-Be- havior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains. Secondly, a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems, and the interaction relationships of the matrix elements are used to obtain an initial set of change paths. Finally, a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters. The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train＇s bogie to show its feasibility and effectiveness. This model is not only supportive to response quickly to diversified market requirements, but also helpful to satisfy customer require- ments and reduce product development lead time. The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.

关键词： Complex product systems Design changemodel - Propagation path analysis Propagation spacereduction Rough set

Effects of working parameters on gasoline engine exergy balance

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Journal of Central South University 2013年第7期20卷 1938-1946页

作者： LIU Jing-ping FU Jian-qin feng Ren-hua ZHU guo-hui Research Center for Advanced Powertrain Technology Hunan University Changsha 410082 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body (Hunan University) Changsha 410082 China

To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exergy balance model was built. The working processes of gasoline engine were simulated by using the GT-power. In this way, the required parameters were calculated and then gasoline engine exergy balance was obtained by programming on computer. On this basis, the influences of various parameters on exergy balance were analyzed. Results show that, the proportions of various forms of exergy in gasoline engine from high to low are irreversible loss, effective work, exhaust gas exergy and heat transfer exergy. Effective exergy proportion fluctuates with cylinder volumetric efficiency at full load, while it always increases with break mean effective pressure （BMEP） at part load. Exhaust gas exergy proportion is more sensitive to speed, and it increases with speed increasing except at the highest speed. The lower proportion of heat transfer exergy appears at high speed and high load. Irreversible loss is mainly influenced by load. At part load, higher BMEP results in lower proportion of irreversible loss; at full load, the proportion of irreversible loss changes little except at the highest speed.

关键词： gasoline engine exergy balance waste heat recovery thermal efficiency energy conservation

Second order conformal multi-symplectic method for the damped Korteweg–de Vries equation

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Chinese Physics B 2019年第5期28卷 20-26页

作者： feng guo Fujian Province University Key Laboratory of Computational Science School of Mathematical Sciences Huaqiao University

A conformal multi-symplectic method has been proposed for the damped Korteweg–de Vries(DKdV) equation, which is based on the conformal multi-symplectic structure. By using the Strang-splitting method and the Preissmann box scheme,we obtain a conformal multi-symplectic scheme for multi-symplectic partial differential equations(PDEs) with added dissipation. Applying it to the DKdV equation, we construct a conformal multi-symplectic algorithm for it, which is of second order accuracy in time. Numerical experiments demonstrate that the proposed method not only preserves the dissipation rate of mass exactly with periodic boundary conditions, but also has excellent long-time numerical behavior.

关键词： conformal multi-symplectic method damped Korteweg–de Vries (KdV) equation dissipation preservation