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Transportation Safety and Environment 2024年第1期6卷 47-55页

作者： Hua Chen Chenyang Zhang Jieyu Zhang Ya Shu Xinjian Qi Chaozhe Jiang sichuan FAST Fire Safety Assessment co. LTD.Chengdu 610036SichuanChina School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 611756SichuanChina sichuan Fire Research Institute of MEM Chengdu 610036SichuanChina Shenzhen Metro group co. LTD.Shenzhen 518026GuangdongChina

Because of its large capacity,high efficiency and energy savings,the subway has gradually beco.e the primary mode of transportation for citizens.A high density of passengers exists within a large-passenger-flow subway station,and the number of casualties and injuries during a fire emergency is *** this paper,Pathfinder software and on-site measured data of Pingzhou station in Shenzhen(china)were utilized to simulate a fire emergency evacuation in a large-passenger-flow subway *** Required Safe Egress Time(RSET),number of passengers and flow rates of stairs and escalators were analysed for three fire evacuation scenarios:train fire,platform fire and hall *** evacuation time of the train fire,which was 1173 s,was the longest,and 3621 occupants needed to evacuate when the train was fully *** co.ld not co.plete the evacuation within 6 mins in all three fire evacuation scenarios,which does not meet the current standard requirements and *** changing the number of passengers and the number of stairs for evacuation,the flow rate capacity and evacuation time were explored,which have reference values for safety management and emergency evacuation plan optimization during peak hours of subway operation.

关键词： fire emergency evacuation large-passenger-flow subway station on-site measured data Pathfinder

Effect of crevice density on biological soil crust development on rock cut slope in mountainous regions,sichuan,china

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Eco.ogical Processes 2023年第1期12卷 46-63页

作者： Maoqiang Zhao Wanqiu Pu Jie Du Wenhu Liu Qian Zhang Yanmei Liu Li Xiao Yingwei Ai Chengmin Huang Department of Environmental Science and Engineering Sichuan UniversityNo.24 South Section 1Yihuan RoadChengdu 610065China Jiuzhaigou Administration Bureau Jiuzhaigou 623402SichuanChina School of Life Science Sichuan UniversityChengdu 610064SichuanChina sichuan Institute of Geological Engineering Investigation group co. Ltd.Chengdu 610072SichuanChina

Background The rock cut slope(RCS)co.ld cause damage to regional eco.ogical functions and landscapes and requires *** soil crusts(BSCs)are pioneer and dominant co.onizers during the initial reco.ery *** accelerate the natural reco.ery of RCS,the development process and influencing agents of BSC should be ***,the area index of crevices(IR),BSC co.erage(co.)and biomass(BM),soil weight(SW),and major soil nutrients[organic carbon(OC),total nitrogen(TN)and total phosphorus(TP)]co.tent,co.lected from 164 quadrats on 13 RCSs in the mountainous area of west sichuan Province,china,were measured,to explore the effect of crevice of RCS on BSC *** Soil OC,TN and TP on RCSs ranged from 18.61 to 123.03 g kg^(-1),0.96 to 6.02 g kg^(-1)and 0.52 to 2.46 g kg^(-1),respectively,and were approximately to or higher than those on natural *** OC,TN and TP co.tents in soils elevated unsystematically with reco.ery time of *** on RCS distributed along crevices generally and *** the first 13 years of natural reco.ery,co.,BM and SW ranged from 6.5 to 28.2%,14.43 to 67.25 g m^(-2),and 127.69 to 1277.74 g m^(-2),***,BM and SW increased linearly with IR on *** positive co.relation between co. and BM and IR was insignificantly impacted by bedrock,slope aspect and altitude within the reco.ery time less than 13 *** and BM on RCSs increased significantly when the reco.ery time is more than 27 *** Crevice on RCSs co.ld be a major environmental factor which is co.ducive to BSC development and soil accumulation through creating a space for water and soil ***,with the increase of reco.ery time of RCSs,BSCs may grow and reach a stable state with the promotion of soil nutrients,plant growth and microbial *** results provide a development process of BSC that from inside to outside the crevices on *** the areas with stable rock strata and a low risk of geological disast

关键词： Rock cut slope Crevice density Natural reco.ery Biological soil crust Soil organic carbon Soil total nitrogen Soil total phosphorus

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Investigation and measurement of old building response to the overlapped shield tunnel of multiple schemes in the sandy co.ble stratum

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Underground Space 2024年第2期15卷 260-274页

作者： Xue Li Aopeng Geng School of Geoscience and Technology Southwest Petroleum UniversityChengduSichuan 610500China china Railway co.struction Bridge Engineering Bureau group co. Ltd.Tianjin 300300China

Ground movements due to tunneling are beco.ing increasingly critical as buildings are located around co.struction *** study proposes a new co.bined reinforcement method using a foundation grouting oblique pipe *** former improves the bearing capacity of the subsoil,and the latter blocks the transmission of soil deformation,which weakens the influence of co.struction during overlapped tunnel *** on this new method,a case study of the shield tunneling response to an old building in Line 6 of china’s Chengdu Metro is ***,three-dimensional numerical models without reinforcement,traditional foundation grouting reinforcement,and the new co.bined reinforcement schemes were *** numerical simulation performance was verified using a set of field instrumentation data,which demonstrated that the old building response to the overlapped tunnels was under co.trol,and the maximum deformation,angular distortion,and principal tensile strain of the building were 5.25 mm,5.1010–6 rad/m,and 0.0081%,*** with the traditional reinforcement scheme,the deformation,angular distortion,and principal tensile strain in the co.bined reinforcement scheme were reduced by 54.78%,71.02%,and 70.22%,*** results have important implications for the design and co.struction of shield tunnels and their response to old buildings.

关键词： Overlapped tunnels Reinforcement schemes Under-crossing Old building Numerical simulation

The Dual Ico.ic Features and Key Enabling Technologies of 6G

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Engineering 2023年第9期28卷 7-10页

作者： Shanzhi Chen Shaoli Kang National Key Laboratory of Wireless mobile co.munications China Information Communication Technology Group Co.Ltd.(CICT)Beijing 100191China

*** Since the 1980s,when the first generation(1G)of mobile networks came into being,mobile co.munications have been developing with the trend of a generational upgrade occurring every *** present,the fifth generation(5G)is in the co.mercial stage and the sixth generation(6G)is in the research *** is expected that the standardization for 6G will debut in the year 2025,and the first version for co.mercialization will be launched in *** the purpose of better understanding 6G.

关键词： mobile Dual networks

The development of mine digitization information system and its application to the Lanping Pb-Zn mine

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Chinese Journal Of Geochemistry 2008年第3期27卷 317-324页

作者： YAN Yongfeng QIN Dexian YU Yangxian LI Shilei JIA Fengqin WANG Xiaoli LIU Fangcheng Kunming University of Science and Technology Kunming 650093 China sichuan Chuanwei group co. Ltd. Chengdu 610100 China

To co.pile the software package of the mine digitization information system in terms of the principle and methods of mathematics geology and geographic information system using co.puter languages such as VB and Matlab,this paper introduces the function co.position and operating environment of this information system,and illustrates the function and effectiveness of the software package as exemplified by the Lanping Pb-Zn mine,Yunnan Province.

关键词：矿山数字化信息系统铅锌矿资源

Development of an ultra-high-pressure rotary co.bined dynamic seal and experimental study on its sealing performance in deep energy mining co.ditions

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Petroleum Science 2022年第3期19卷 1305-1321页

作者： Wei Huang Gan Feng Hui-Lan He Jian-Zhong Chen Jiu-Quan Wang Zhao Zhao Key Laboratory of Deep Earth Science and Engineering(sichuan University) Ministry of EducationSichuan UniversityChengdu610065SichuanChina School of Mechanical Engineering Sichuan UniversityChengdu610065SichuanChina co.lege of Water Resource&Hydropower Sichuan UniversityChengdu610065SichuanChina Jin Shi Drill Tech co. LtdTangshan063004HebeiChina Pingdingshan Tianan co.l Mining co. LTD.Pingdingshan467000HenanChina Xi'an Research Institute China Coal Technology&Engineering Group CorpXi'an710077ShaanxiChina

With the co.tinuous development of deep oil and gas,minerals,geothermal resources,and other resources,there are increasingly more stringent requirements for *** particular,the ultra-highpressure dynamic seals of deep mining device need to be ***,co.sidering the use of dynamic seals in unique deep mining environments,an ultra-high-pressure rotating co.bined dynamic seal was designed and developed and its sealing performance was experimentally measured and *** results show that the experimental device can operate stably under a pressure of up to150 MPa and a rotating speed of 76 r/min,and can also operate normally under a rotating speed of up to 140 r/min and a sealing pressure of 120 *** the operation of the ultra-high-pressure rotating co.bined dynamic seal,the sealing ring does not show obvious damage,which vouches for its sealing *** leakage of flow and pressure was detected in the all seal structures within the sealing pressure range of 0-150 ***,the dynamic sealing performance of the device is intact under ultra-high-pressure co.ditions and can be applied in deep mining environments at a certain *** research and development of this device can aid future deep energy exploration and exploitation.

关键词： Deep energy exploitation Ultra-high-pressure Rotating co.bination dynamic seal Development of test equipment

All-optical ultra-wideband doublet signal source based on the cross-gain modulation in a semico.ductor optical amplifier

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Optoelectronics Letters 2012年第2期8卷 89-92页

作者：赵赞善李培丽郑加金潘婷婷黄世杰罗友宏 co.lege of Optoelectronic Engineering Nanjing University of Posts&Telecommunications china mobile group Hainan co. LTD

We propose a novel scheme to generate the ultra-wideband (UWB) doublet signal pulse based on the cross-gain modulation (XGM) in a semico.ductor optical amplifier (SOA). In the scheme, only an optical source and an SOA are needed. As there is only one wavelength included in the output doublet signal pulse, no time difference between the upper and down pulses is introduced during the transmission process. By using the software of Optisystem 7.0, the impacts of the optical power, the SOA current, the wavelength and the input signal pulse width on the generated doublet pulse are simulated and tudied numerically. The results show that when the pulse width of the input signal pulse is larger, the output signal pulse is better, and is insensitive to the change of wavelength. In addition, the ultra-wideband positive and negative monocycles can be generated by choosing suitable optical source power and SOA current.

关键词： Semico.ductor optical amplifiers

Non-co.perative power co.trol game for adaptive modulation and co.ing

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The Journal of china Universities of Posts and Teleco.munications 2010年第3期17卷 31-37页

作者： GAO Peng MENG De-xiang CHENG Nan LIANG Shuang-chun TU Guo-fang School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China china mobile group Design Institute co. Ltd Beijing 100080 China

Adaptive modulation and co.ing （AMC） provides the flexibility to match modulation and co.ing scheme （MCS） to signal to interference plus noise ratio （SINR） of users. To reduce the transmission power and maintain the transmission quality, power co.trol is normally co.bined with AMC. While the target SINR of power co.trol is fixed, therefore non-co.perative power co.trol game for AMC （NPGA） algorithm was proposed to adapt to the dynamic target SINR changes acco.ding to MCS. In NPGA, we formulate system transmission efficiency via utility, where the utility function is co.structed based on the modulation and co.ing efficiency with non-co.perative game theory. It is demonstrated theoretically that NPGA can satisfy the co.ditions of the supermodular games, and its solution is optimal. The simulation results show that NPGA can improve system transmission efficiency and signal quality with low transmission power, and the co.vergence performance of NPGA is more fast-effectiveness co.pared with geometric programming algorithms.

关键词： power co.trol AMC SINR game theory utility function

Extraction of the dynamic plastic behavior of AlON single crystals by nanoimpact

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Journal of Advanced Ceramics 2024年第10期13卷 1566-1577页

作者： Haomin Wang Mao Deng Zhangyi Huang Kailei Lu Jiebin Shen Hongjiang Qian Zhiyong Huang Jianqi Qi Qingyuan Wang Institute for Advanced Study Chengdu UniversityChengdu 610106China co.lege of Physics Sichuan UniversityChengdu 610064China Chengdu Holy Technology group co. Ltd.Chengdu 610041China School of Aeronautics and Astronautics Sichuan UniversityChengdu 610064China

Investigating the dynamic mechanical behavior of single-crystal aluminum oxynitride(AlON)is fascinating and crucial for understanding material performance in relevant ***,few studies have explored the dynamic mechanical properties of AlON single *** this study,a series of nanoimpact experiments(representative strain rateε˙r≈102s^(-1))were performed on three principal orientations((010),(101),and(111))of grains to extract the dynamic mechanical responses of AlON single *** results reveal that the dynamic plasticity of an AlON single crystal is governed by a co.bination of mechanisms,including dislocation motion and ***,the localized amorphization induced by mechanical deformation has a softening effect(a lower dynamic hardness).The crystallographic orientation affects the dynamic hardness similarly to the static *** particular,the(111)orientation results in the highest hardness,whereas the(010)orientation is the softest among the three principal *** dependency aligns with the expectations derived from applying Schmid ***,both the dynamic and static hardnesses exhibit typical indentation size effects(ISEs),which can be effectively described via the strain gradient theory associated with the geometrically necessary *** addition,the size and rate dependencies of the dynamic hardness can be deco.pled into two independent terms.

关键词： nanoimpact aluminum oxynitride(AlON) indentation size effect(ISE) amorphization dislocations

Mechanical Properties and Microco.mic Properties of Self-co.pacting co.crete Modified by co.pound Admixtures

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Journal of Renewable Materials 2022年第4期10卷 897-908页

作者： Song Yang Bing Qi Zubin Ai Zhensheng Cao Shiqin He Lijun Li Power china Roadbridge group co. Ltd.Beijing100048China co.lege of Civil Engineering North China University of TechnologyBeijing100043China sichuan Tieke New Building Materials co. Ltd.Chengdu610000China

It has beco.e a research hotspot to explore raw material substitutes of *** is important to research the mechanical properties of self-co.pacting co.crete(SCC)with slag powder(SP)and rubber particle(RP)replacing cement and co.rse aggregate,respectively.12 kinds of co.posite modified self-co.pacting co.crete(CMSCC)specimens were prepared by using 10%,20%and 30%SP and 30%,40%,50%and 60%*** rheological properties,mechanical properties and microstructure of the CMSCC were *** indicate that the workability,co.pressive strength,splitting tensile strength and flexural strength of CMSCC prepared by 20%SP and less than 40%RP are *** order to maximize the utilization of waste materials,20%SP and 40%RP can be used as the optimal ratio of the co.bined *** microstructure shows that the addition of proper amount of SP is co.ducive to the formation of increasingly more uniform C-S-H gel.C-SH gel can fill the internal pores of the sample and enhance the adhesion between the aggregate,thus improving the mechanical properties of *** has a rougher surface and lower density and stiffness,which inhibits the workability and mechanical properties of *** above research results have important theoretical and practical significance for the selection of raw materials of self-co.pacting co.crete and the rational use of industrial wastes.

关键词： Self-co.pacting co.crete slag powder rubber particle mechanical properties microstructure