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Resist-decreasing effects of rock bolts on strength of rock mass around roadway——insight from numerical modeling

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Mining Science and Technology 2009年第4期19卷 425-429页

作者： gao fu-qiang XIE Yao-she Mining and Designing Branch Central Coal Research Institute Beijing 100013 China Department of Earth Sciences Simon Fraser University Burnaby VSC2Z9 Canada School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

To investigate the resist-decreasing effects of rock bolts on the strength of the rock mass around a roadway, a compara- tive study has been carded out using the numerical analysis code FLAC3D. An unsupported and a rock bolt supported model have been built for comparison. Two types of rock mass strength, the uniaxial compressive strength （UCS） and the wiaxial compressive strength （TCS） of rock mass have been obtained from each model, using a prepared Fish based on the Mohr-Coulomb criterion. The results indicate that when a roadway is excavated, both the UCS and TCS in a definite local rock mass around the roadway would inevitably decrease, no matter whether the roadway is supported or not. The major decreasing region did not settle in the middle of the roadway surface, but within a deeper horizon into the rock mass. The resist-decreasing effects of rock bolts both on the UCS and the TCS of rock mass around roadway are significant.

关键词： resist-decrease rock mass strength rock bolts numerical simulation

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新形势下节能报告编制的典型问题及策略分析

节能 2024年第1期43卷 126-128页

作者：刘艺苏天亨高富强广东能效科技有限公司广东广州511447 广州广重企业集团有限公司广东广州510000

2023年3月,我国国家发展和改革委员会对《固定资产投资项目节能审查办法》(以下简称:新《办法》)进行修订,新《办法》对节能报告提出新的要求。阐述了新《办法》出台后节能报告编制过程中常见的问题,结合实际工作经验,对节能报告的编制... 详细信息

2023年3月,我国国家发展和改革委员会对《固定资产投资项目节能审查办法》(以下简称:新《办法》)进行修订,新《办法》对节能报告提出新的要求。阐述了新《办法》出台后节能报告编制过程中常见的问题,结合实际工作经验,对节能报告的编制提出应对措施及对策建议。

关键词：节能审查节能报告固定资产投资项目

Spatial compartmentalization and temporal stability of associated microbiota in Pacific oyster Crassostrea gigas

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Journal of Oceanology and Limnology 2024年第4期42卷 1348-1358页

作者： qiang fu Zichao YU Junyan ZHAO Lei gao Ning KONG Lingling WANG Linsheng SONG Liaoning Key Laboratory of Marine Animal Immunology and Disease Control Dalian Ocean UniversityDalian 116023China functional Laboratory of Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control Dalian Ocean UniversityDalian 116023China

The Pacific oyster Crassostrea gigas,one of the most exploited molluscs in the world,has suffered from massive mortality in recent decades,and the occurrence mechanisms have not been well *** this study,to reveal the relationship of associated microbiota to the fitness of oysters,temporal dynamics of microbiota in the gill,hemolymph,and hepatopancreas of *** during April 2018-January 2019 were investigated by 16 S rRNA gene *** microbiota in *** exhibited tissue heterogeneity,of which Spirochaetaceae was dominant in the gill and hemolymph while Mycoplasmataceae enriched in the ***-occurrence network demonstrated that the gill microbiota exhibited higher inter-taxon connectivity while the hemolymph microbiota had more *** richness(Chao 1 index)and diversity(Shannon index)of microbial community in each tissue showed no significant seasonal variations,except for the hepatopancreas having a higher richness in the ***,beta diversity analysis indicated a relatively stable microbiota in each tissue during the sampling period,showing relative abundance of the dominant taxa exhibiting temporal *** indicate that the microbial community in *** showed a tissue-specific stability with temporal dynamics in the composition,which might be essential for the tissue functioning and environmental adaption in *** work provides a baseline microbiota in *** and is helpful for the understanding of host-microbiota interaction in oysters.

关键词： Pacific oyster associated microbiota spatial compartmentalization temporal stability

Combined blasting for protection of gob-side roadway with thick and hard roof

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3165-3180页

作者： qiang fu Jun Yang Yubing gao Changjiang Li Hongxu Song Yuxuan Liu Xing Wu State Key Laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

The deformation control of surrounding rock in gobside roadway with thick and hard roof poses a significant challenge to the safety and efficiency of coal *** address this issue,a novel approach combining directional and non-directional blasting techniques,known as combined blasting,was *** study focuses on the experimental investigation of the proposed method in the 122108 working face in Caojiatan Coal Mine as the engineering *** initial phase of the study involves physical model experiments to reveal the underlying mechanisms of combined blasting for protecting gob-side roadway with thick and hard *** results demonstrate that this approach effectively accelerates the collapse of thick and hard roofs,enhances the fragmentation and expansion coefficient of gangue,facilitates the filling of the goaf with gangue,and provides support to the overlying strata,thus reducing the subsidence of the overlying strata above the ***,the method involves cutting the main roof into shorter beams to decrease the stress and disrupt stress transmission *** numerical simulations were conducted to corroborate the findings of the physical model experiments,thus validating the accuracy of the experimental ***,field engineering experiments were performed,affirming the efficacy of the combined blasting method in mitigating the deformation of surrounding rock and achieving the desired protection of the gob-side roadway.

关键词： Thick and hard roof Surrounding rock control Combined blasting Fragmentation and expansion support stress relief

Pericollapse Stage of Osteonecrosis of the Femoral Head： A Last Chance for Joint Preservation

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Chinese Medical Journal 2018年第21期131卷 2589-2598页

作者： Qing-Yu Zhang Zi-Rong Li fu-qiang gao Wei Sun Department of Orthopaedic Graduate School of Peking Union Medical College China-Japan Friendship Hospital Institute of Clinical Medicine Beijing 100029 China Department of Orthopaedic Centre for Osteonecrosis and Joint-Preserving and Reconstruction China-Japan Friendship Hospital Beijing 100029 China Department of Orthopaedic Peking University China-Japan Friendship School of Clinical Medicine Beijing 100029 China

Objective： To propose a new definition of the pericollapse stage of osteonecrosis of the femoral head （ONFH） and review its significance in disease diagnosis and treatment selection. Data Sources： A search for eligible studies was conducted in three electronic databases including PubMed, Cochrane Library, and Embase up to August 10, 2018, using the following keywords：＂osteonecrosis＂, ＂prognosis＂, and ＂treatment＂. Study Selection： Investigations appraising the clinical signs, symptoms, and imaging manifestations in different stages of ONFH were included. Articles evaluating the prognosis of various joint-preserving procedures were also reviewed. Results： The pericollapse stage refers to a continuous period in the development of ONFH from the occurrence of subchondral fracture to early collapse （〈2 mm）, possessing specific imaging features that mainly consist of bone marrow edema and joint effusion on magnetic resonance imaging （MR1）, crescent signs on X-ray films, and clinical manifestations such as the sudden worsening of hip pain. Accumulating evidence has indicated that these findings may be secondary to the changes after subchondral fractures. Of note. computed tomography provides more information for identifying possible subchondral fractures than does MRI and serves as the most sensitive tool for grading the pericollapse lesion stage. The pericollapse stage may indicate a high possibility of progressive disease but also demonstrates satisfactory long- and medium-term outcomes fbr joint-preserving techniques. In tact, if the articular surface subsides more than 2 mm, total hip arthroplasty is preferable. Conclusions： The pericollapse stage with distinct clinical and imaging characteristics provides a last good opportunity for the use of joint-preserving techniques. It is necessary to separate the pericollapse stage as an independent state in evaluating the natural progression of ONFH and selecting an appropriate treatment regimen.

关键词： Joint-Preserving Procedure Osteonecrosis of the Femoral Head Pericollapse Prognosis

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-Hao Yang Tong Wu qiang fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Focused extra-corporeal shockwave treatment during early stage of osteonecrosis of femoral head

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Chinese Medical Journal 2019年第15期132卷 1867-1869页

作者： Qi-Wei Wang Qing-Yu Zhang fu-qiang gao Wei Sun Department of Orthopedics Peking University China-Japan Friendship School of Clinical Medicine Beijing 100029 China Department of Orthopedics Shandong Provincial Hospital Affiliated to Shandong University Jinan Shandong 250021 China Department of Orthopedics China-Japan Friendship Hospital Beijing 100029 China

In recent years,increasing evidence has demonstrated that extra-corporeal shockwave therapy (ESWT) can offer an effective and non-invasive method for the treatment of musculoskeletal disorders,such as shoulder tendinopathies,lateral epicondylopathy of the elbow,greater trochanteric pain syndrome,patellar tendinopathy,Achilles tendinopathy,plantar fasciitis,and bone disorders.[1,2]As a safe,cheap,and non-invasive therapeutic method,ESWT has played a promising role in orthopedic medicine.[3-5] Inspired by this,several researchers have attempted to investigate its use for treating osteonecrosis of the femoral *** deserves being recommended as the optimal choice for osteonecrosis of the femoral head (ONFH).

关键词： extra-corporeal shockwave osteonecrosis of femoral head

Four Methods for Calculating Blood-loss after Total Knee Arthroplasty

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Chinese Medical Journal 2015年第21期128卷 2856-2860页

作者： fu-qiang gao Zi-Jian Li Ke Zhang Wei Sun Hong Zhang Department of Orthopedics China-Japan Friendship Hospital Beijing 100029 China Department of Orthopedics Peking University Third Hospital Beijing 100191 China Department of Orthopedics The First Affiliated Hospital of People's Liberation Army General Hospital Beijing 100037 China

Background： Currently, various calculation methods for evaluating blood-loss in patients with total knee arthroplasty （TKA） are applied in clinical practice. However, different methods may yield different results. The purpose of this study was to determine the most reliable method for calculating blood-loss after primary TKA. Methods： We compared blood-loss in 245 patients who underwent primary unilateral TKA from February 2010 to August 2011. We calculated blood-loss using four methods： Gross equation, hemoglobin （Hb） balance, the Orthopedic Surgery Transfusion Hemoglobin European Overview （OSTHEO） formula, and Hb-dilution. We determined Pearson＇s correlation coefficients for the four methods. Results： There were large differences in the calculated blood-loss obtained by the four methods. In descending order of combined correlation coefficient based on calculated blood-loss, the methods were Hb-balance, OSTHEO formula, Hb-dilution, and Gross equation. Conclusions： The Hb-balance method may be the most reliable method of estimating blood-loss after TKA.

关键词： Arthroplasty Blood-loss Calculation Method Knee Replacement

MADDPG-D2: An Intelligent Dynamic Task Allocation Algorithm Based on Multi-Agent Architecture Driven by Prior Knowledge

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2559-2586页

作者： Tengda Li Gang Wang qiang fu College of Air and Missile Defense Air Force Engineering UniversityXi’an710051China

Aiming at the problems of low solution accuracy and high decision pressure when facing large-scale dynamic task allocation(DTA)and high-dimensional decision space with single agent,this paper combines the deep reinforce-ment learning(DRL)theory and an improved Multi-Agent Deep Deterministic Policy Gradient(MADDPG-D2)algorithm with a dual experience replay pool and a dual noise based on multi-agent architecture is proposed to improve the efficiency of *** algorithm is based on the traditional Multi-Agent Deep Deterministic Policy Gradient(MADDPG)algorithm,and considers the introduction of a double noise mechanism to increase the action exploration space in the early stage of the algorithm,and the introduction of a double experience pool to improve the data utilization rate;at the same time,in order to accelerate the training speed and efficiency of the agents,and to solve the cold-start problem of the training,the a priori knowledge technology is applied to the training of the ***,the MADDPG-D2 algorithm is compared and analyzed based on the digital battlefield of ground and air *** experimental results show that the agents trained by the MADDPG-D2 algorithm have higher win rates and average rewards,can utilize the resources more reasonably,and better solve the problem of the traditional single agent algorithms facing the difficulty of solving the problem in the high-dimensional decision *** MADDPG-D2 algorithm based on multi-agent architecture proposed in this paper has certain superiority and rationality in DTA.

关键词： Deep reinforcement learning dynamic task allocation intelligent decision-making multi-agent system MADDPG-D2 algorithm