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ANALYSIS OF BATCH ARRIVAL QUEUE WITH RANDOMIZED VACATION POLICY AND AN UN-RELIABLE SERVER

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Journal of Systems Science & Complexity 2012年第4期25卷 759-777页

作者： Jau Chuan ke kai Bin HUANG Department of Applied Statistics National Taichung University of Science and Technology Department of Engineering Information System Development Ardebtec Corporation Ltd.

This paper examines an M[x]/G/1 queueing system with an unreliable server and a delayed repair, in which the server operates a randomized vacation policy with multiple vacations. Whenever the system is empty, the server immediately takes a,vacation. If there is at least one customer found waiting in the queue upon returning from a vacation, the server will be immediately activated for service. Otherwise, if no customers are waiting for service at the end of a vacation, the server either remains idle with probability p or leaves for another vacation with probability 1 -p. Whenever one or more customers arrive when the server is idle, the server immediately starts providing service for the arrivals. The server may also meet an unpredictable breakdown and the repair may be delayed. For such a system the authors derive the distributions of some important system characteristics, such as the system size distribution at a random epoch and at a departure epoch, the system size distribution at the busy period initiation epoch, and the distribution of the idle period and the busy period. The authors perform a numerical analysis for changes in the system characteristics, along with changes in specific values of the system parameters. A cost effectiveness maximization model is constructed to explain the benefits of such a queueing system.

关键词： Cost effectiveness delayed repair randomized vacation queue reliability.

Influence of pore structure on thermal stress distribution inside coal particles during primary fragmentation

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Particuology 2024年第2期85卷 49-61页

作者： kai Qiao Shan Zhong Siyang Tang ke yang Hairong Yue Kui Ma Lei Song Bin Liang School of Chemical Engineering Sichuan UniversityChengdu610065China Institute of New Energy and Low-carbon Technology Chengdu610207China

Thermal stress is an important reason of coal particle primary fragmentation,during which the role of pore structure is *** stress induced fragmentation experiments were conducted with low volatile coal/char particles,and the results show that the fragmentation severity enhances with increasing *** porous thermal stress models were developed with finite element method,and the influences of the pore shape,size,position and porosity on the thermal stress were *** maximum thermal stress inside particle increases with pore curvature,the pore position affects the thermal stress more significantly at the particle center and *** expectation of the maximum tensile thermal stress linearly increases with porosity,making the particles with higher porosity easier to fragment,contrary to the conclusion deduced from the devolatilization *** obtained results are valuable for the analysis of different thermal processes concerning the thermal stresses of the solid feedstocks.

关键词： Coal particle Primary fragmentation Thermal stress Pore structure Porosity

Application of pulsed chemical vapor deposition on the SiO_(2)-coated TiO_(2) production within a rotary reactor at room temperature

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Chinese Journal of Chemical Engineering 2022年第5期35卷 22-31页

作者： ke yang Shan Zhong Hairong Yue Siyang Tang Kui Ma Changjun Liu kai Qiao Bin Liang School of Chemical Engineering Sichuan UniversityChengdu 610065China Institute of New Energy and Low-carbon Technology Chengdu 610207China

Pulsed chemical vapor deposition(P-CVD)is a promising technology for the surface modification of TiO_(2) *** the scale-up application of P-CVD,a custom-designed rotary reactor and corresponding coating process at room temperature was developed in the present *** obtained SiO_(2)-coated TiO_(2) particles were characterized by various measures including high-resolution transmission electron microscope,Fourier transform infrared spectroscopy,X-ray diffraction,*** results illustrated that the SiO_(2) films with a thickness of(3.7±0.7)nm were successfully deposited onto the surface of TiO_(2) *** to the dye degradation tests and acid solubility measurement,the deposited film can effectively inhibit the photocatalytic activity and enhance the weatherability of the TiO_(2) *** potential measurements showed that the SiO_(2)-coated TiO_(2) is possible to be stably dispersed in the pH range of 6.9–*** coating process made the whiteness of TiO_(2) particles decreased slightly but still sufficient(97.3±0.1)for ***,the properties of the TiO_(2) particles coated by PCVD were compared with the particles coated by traditional wet chemical *** is shown that the P-CVD can produce thinner but denser films with better photoactivity suppression *** developed coating process within the rotary reactor was proved practically feasible and convenient for the scale-up production of SiO_(2)-coated TiO_(2) via P-CVD.

关键词： Film Pulsed-CVD Scale-up Deactivation Pigmentary properties

AInvR:Adaptive Learning Rewards for Knowledge Graph Reasoning Using Agent Trajectories

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Tsinghua Science and Technology 2023年第6期28卷 1101-1114页

作者： Hao Zhang Guoming Lu ke Qin kai Du School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Multi-hop reasoning for incomplete Knowledge Graphs(KGs)demonstrates excellent interpretability with decent *** Learning(RL)based approaches formulate multi-hop reasoning as a typical sequential decision *** intractable shortcoming of multi-hop reasoning with RL is that sparse reward signals make performance *** mainstream methods apply heuristic reward functions to counter this ***,the inaccurate rewards caused by heuristic functions guide the agent to improper inference paths and unrelated object *** this end,we propose a novel adaptive Inverse Reinforcement Learning(IRL)framework for multi-hop reasoning,called AInvR.(1)To counter the missing and spurious paths,we replace the heuristic rule rewards with an adaptive rule reward learning mechanism based on agent’s inference trajectories;(2)to alleviate the impact of over-rewarded object entities misled by inaccurate reward shaping and rules,we propose an adaptive negative hit reward learning mechanism based on agent’s sampling strategy;(3)to further explore diverse paths and mitigate the influence of missing facts,we design a reward dropout mechanism to randomly mask and perturb reward parameters for the reward learning *** results on several benchmark knowledge graphs demonstrate that our method is more effective than existing multi-hop approaches.

关键词： Knowledge Graph Reasoning(KGR) Inverse Reinforcement Learning(IRL) multi-hop reasoning

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新建超超临界直流锅炉的化学清洗

清洗世界 2016年第10期32卷 45-48页

作者：夏跃林郭云飞李昭张向涛王凯杨科李卫华能东方电厂海南东方572600 西安热工研究院有限公司陕西西安710054

针对超超临界锅炉特点及基建机组化学清洗的目的,按照火力发电厂清洗导则的要求,介绍某电厂1号机组化学清洗范围、清洗工艺和控制参数,分析和讨论了EDTA清洗过程中应注意的事项。

关键词：锅炉超超临界化学清洗双氧水 EDTA

Linear stability of plane creeping Couette flow for Burgers fluid

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Acta Mechanica Sinica 2013年第1期29卷 12-23页

作者： kai-Xin Hu Jie Peng ke-Qin Zhu Department of Engineering Mechanics Tsinghua University

It is well known that plane creeping Couette flow of UCM and Oldroy-B fluids are linearly stable. However, for Burges fluid, which includes UCM and Oldroyd-B fluids as special cases, unstable modes are detected in the present work. The wave speed, critical parameters and perturbation mode are studied for neutral waves. Energy analysis shows that the sustaining of perturbation energy in Poiseuille flow and Couette flow is completely different. At low Reynolds number limit, analytical solutions are obtained for simpli- fied perturbation equations. The essential difference between Burgers fluid and Oldroyd-B fluid is revealed to be the fact that neutral mode exists only in the former.

关键词： Linear stability theory Burgers fluid Creeping Couette flow - Elastic instability

Effect of oxidation treatment on the adsorption and the stability of mercury on activated carbon

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Journal of Environmental Sciences 2006年第6期18卷 1161-1166页

作者： HU Chang-xing ZHOU Jin-song LUO Zhong-yang HE Sheng WANG Guang-kai CEN ke-fa State key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Oxidation treatment on the adsorption and the stability of Hg on activated carbon （AC） was inrestigated. Both MnO2-AC and FeCl3-AC were produced during oxidation treatment. The measurement of modified AC＇s mercury adsorption capacity was conducted in a simulated coal-fired flue gas by adsorbing test apparatus. TCLP and column leaching methods were used to test the stability of mercury adsorbed on ACs. The results indicate that the oxidation treatment changed the pore structure of the AC and modified the carbon surface by creating chemical components such as MnO4^-, Mn^4＋, O, NO^3-, Fe^3＋, Cl^-, etc. The Hg sorption capacity on MnO2-AC or FeCl3-AC was about three times higher than that of untreated carbon. In addition, the mercury control cost of each of the formers was about the half cost of the untreated carbon. The stability of Hg absorption was studied, it found that mercury adsorbed on the oxidation treated AC was not better than that of untreated carbon. It could concluded that the insoluble form of Hg is very important to the stability of mercury adsorbed on AC. This study suggests that the FeCl3-AC is the best absorbent for Hg with high adsorption capacity, better Hg adsorption stability in leaching environment, and lower cost among the three ACs tested.

关键词： activated carbon oxidation treatment Hg adsorption stability

Expression of angiostatin cDNA in human hepatocellular carcinoma cell line SMMC-7721 and its effect on implanted carcinoma in nude mice

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World Journal of Gastroenterology 2004年第10期10卷 1421-1424页

作者： kai-ShanTao ke-FengDou Xing-AnWu DepartmentofHepatobiliarySurgery XijingHospitalFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina DepartmentofMicrobiology FacultyofBasicMedicineFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina

AIM: To transfect murine angiostatin cDNA into human hepatocellular carcinoma cell line SMMC-7721 and to investigate its effects on implanted carcinoma in nude ***: A eukaryotic expression vector of pcDNA3.1-mAST containing murine angiostatin was constructed. Then pcDNA3.1-mAST plasmid was transfected into cell line SMMC-7721 by Lipofectamine. The resistant clone was screened by G418 filtration and identified by RT-PCR and Western blotting. Nude mice were divided into three groups of 10 each. Mice in blank control group were only injected with SMMC-7721 cells. Mice in vector control group were injected with SMMC-7721 cells transfected with pcDNA3.1 (+) vector,whereas mice in angiostatin group were injected with SMMC-7721 cells transfected with pcDNA3.1-mAST ***, mass and microvessel density (MVD) of the tumors in different groups were measured and ***: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). pcDNA3.1-mAST was successfully transfected into SMMC-7721 cell line and showed stable expression in this cell *** significant difference was observed in the growth speed of SMMC-7721 cells between groups transfected with and without angiostatin cDNA. Tumor volume, mass and MVD in the angiostatin group were significantly lower than those in the blank control group and vector control group (P<0.01).The inhibitory rate of tumor reached 78.6%. Mass and MVD of the tumors only accounted for 34.6% and 48.9% respectively of those in the blank control ***: Angiostatin cDNA could be stably expressed in human hepatocellular carcinoma cell line SMMC-7721 without obvious inhibitory effects on the growth of SMMC-7721 cells. When implanted into nude mice, SMMC-7721 cells transfected with angiostatin cDNA show a decreased tumorigenic capability. It suggests that angiostatin can inhibit tumor growth through its inhibition on angiogenesis in tumors.

关键词：肝细胞癌 SMMC-7721细胞系肿瘤移植动物模型肿瘤抑制

Influence of intrauterine injection of rat fetal hepatocytes on rejection of rat liver transplantation

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World Journal of Gastroenterology 2003年第1期9卷 137-140页

作者： Yan-Lingyang ke-FengDou kai-ZongLi DepartmentofHepatobiliarySurgery XijingHospitalFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina DepartmentofHepatobiliarySurgery XijingHospitalFourthMilitaryMedicalUniversityXi'an710032ShaanxiProvinceChina

AIM: To investigate the influence of immune toleranceinduced by intrauterine exposure to fetal hepatocytes onliver transplantation in the adult ***: LOU/CN rat fetal hepatocytes were injectedinto the fetuses of pregnant CHN rats (14-16 days ofgestation). At 7-9 weeks of age, the surviving male ratsreceived orthotopic liver transplantation (OLT) from maleLOU/CN donors and the survival period was observed andmonitered by mixed lymphocyte reaction assay andcytotoxicity ***: (1) A total of 31 pregnant CHN rats with 172fetuses received fetal hepatocytes from LOU/CN rats viaintrauterine injection. Among them, thirteen pregnant ratsshowed normal parturition, with 74 neonatal rats growingup normally. (2) The mean survival period after OLT in ratswith fetal exposure to fetal hepatocytes was 32.1±3.7 days,which was significantly different from the control (11.8±2.3days, P＜0.01) in rats without fetal induction of immunetolerance. (3) Mixed lymphocyte proliferation assays yieldedremarkable discrepancies between the groups of rats with- orwithout fetal exposure to fetal hepatocytes, with values of8 411±1 361 and 22 473±1 856 (CPM±SD, P＜0.01) respectively.(4) Cytotoxicity assays showed values of 21.2±6.5 % and64.5±7.2 % (P＜0.01) in adult rats with or without fetalinduction of immune ***: Intrauterine injection of fetal hepatocytes intorat fetuses can prolong the survival period of liver transplantadult male rats recipients, inducting immune tolerance in OLT.

关键词：肝移植排斥反应胎儿肝实质细胞子宫内注射免疫耐受