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整函数与亚纯函数的例外集
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作者 漆毅 顾永兴 《重庆大学学报(自然科学版)》 EI CAS CSCD 1995年第5期64-71,共8页
除将Borel可去集引入到整函数及其导数分别取两个小整函数并涉及重值的辐角分布的研究外,还将其引入到以∞为Nevanlinna亏值的亚纯函数及其各阶导数取两个小亚纯函数的辐角分布的研究中,并证明了相应的奇异方向的存在性。
关键词 整函数 Bord可去集 半纯函数 导数
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Coal pillar design when considered a reinforcement problem rather than a suspension problem 被引量:2
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作者 Russell Frith Guy Reed 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第1期11-19,共9页
Current coal pillar design is the epitome of suspension design.A defined weight of unstable overburden material is estimated, and the dimensions of the pillars left behind are based on holding up that material to a pr... Current coal pillar design is the epitome of suspension design.A defined weight of unstable overburden material is estimated, and the dimensions of the pillars left behind are based on holding up that material to a prescribed factor of safety.In principle, this is no different to early roadway roof support design.However, for the most part, roadway roof stabilisation has progressed to reinforcement, whereby the roof strata is assisted in supporting itself.This is now the mainstay of efficient and effective underground coal production.Suspension and reinforcement are fundamentally different in roadway roof stabilisation and lead to substantially different requirements in terms of support hardware characteristics and their application.In suspension, the primary focus is the total load-bearing capacity of the installed support and ensuring that it is securely anchored outside of the unstable roof mass.In contrast, reinforcement recognises that roof de-stabilisation is a gradational process with ever-increasing roof displacement magnitude leading to ever-reducing stability.Key roof support characteristics relate to such issues as system stiffness, the location and pattern of support elements and mobilising a defined thickness of the immediate roof to create(or build) a stabilising strata beam.The objective is to ensure that horizontal stress is maintained at a level that prevents mass roof collapse.This paper presents a prototype coal pillar and overburden system representation where reinforcement, rather than suspension, of the overburden is the stabilising mechanism via the action of in situ horizontal stresses.Established roadway roof reinforcement principles can potentially be applied to coal pillar design under this representation.The merit of this is evaluated according to failed pillar cases as found in a series of published databases.Based on the findings, a series of coal pillar system design considerations for bord and pillar type mine workings are provided.This potentially allows a more flexible approach to coal pillar sizing within workable mining layouts, as compared to common industry practice of a single design factor of safety(Fo S) under defined overburden dead-loading to the exclusion of other relevant overburden stabilising influences. 展开更多
关键词 Coal PILLAR design OVERBURDEN stability Rock REINFORCEMENT Bord and PILLAR mining
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一个随机微分方程的研究
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作者 李芳 赵生变 《北方交通大学学报》 CSCD 北大核心 2001年第6期97-102,共6页
研究了一个随机微分方程 ,它的解是一特殊的扩散过程 ,其漂移系数是不连续的Borel可测函数 .本文证明了其适应连续过程解的存在和唯一性 ,还指出了它可以进一步推广到更复杂的情形 .
关键词 随机微分方程 扩散过程 漂移系数 反函数 Bord可测函数 适应连续过程解 随机控制
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Rib stability: A way forward for safe coal extraction in India 被引量:1
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作者 Singh Satyendra K. Agrawal Harshit Singh Awanindra P. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期1087-1091,共5页
Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safe... Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earlier formulations for rib stability when applied to case studies gave very low FOS value suggesting significant ground control problems, which were contrary to the field observations. This has necessitated the need to revisit the concept of rib stability. The stress coming on the rib is estimated with the use of numerical modeling technique using the FLAC^(3D) software. The methodology of assessing rib-stability with the help of suggested rib-strength formulation has been validated at eight Indian coal mines. The outcome of this study finds relevance and importance in ensuring underground coal liquidation with improved safety and conservation. 展开更多
关键词 RIB stress estimation Rib-strength Rib-stability Numerical modeling Bord & PILLAR method UNDERGROUND COAL EXTRACTION
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TECTONIC DEFORMATION AND STRONG EARTHQUAKE ACTIVITIES ON THE EAST BORDER OF TIBET PLATEAU
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作者 Zhou Rongjun,Tang Rongchang,Huang Zhuzhi,He Yulin,Yang Tao,Zhou Wei 《地学前缘》 EI CAS CSCD 2000年第S1期298-300,共3页
The tectonic deformation image of Asia Continent can be explained successfully by the model of collision between India secondary continent and Euro\|Asia Plate (P. Molnar and P.Tapponnier, 1975). This paper mainly dis... The tectonic deformation image of Asia Continent can be explained successfully by the model of collision between India secondary continent and Euro\|Asia Plate (P. Molnar and P.Tapponnier, 1975). This paper mainly discusses the characteristics of tectonic deformation and strong earthquake activities on the east border of Tibet Plateau.1\ Characteristics of tectonic deformation on the east border of Tibet Plateau\;Controlled by the flow of the plateau crust material, the movement of the east border of Tibet plateau is mainly horizontal so as to produce two slipping\|block: one results from the slide out of Chuandian Rhombus Block along the SSE direction, the other results from the lateral extrusion of Chuanqing Block with the SEE direction. The slip rate of the north part of Chuandian Rhombus Block, the west region of Sichuan, is 5~8mm/a;2~3mm/a on the south part (the center part of Yunan); the slip rate of Chuanqing is 3~5mm/a and <1mm/a on Longmenshan region (Tang Rongchang, 1993). The slipping features of the blocks directly decide the movement characters of different fault systems: the uniform sinistral shear movement on the east boundary fault of Chuandian Rhombus Block, from the geological viewpoint, the average horizontal slip rate is about 10mm/a, and 5~8mm/a on the Anninghe, Zemuhe and Xiaojiang faults. The dextral shear movement can be found on the west boundary faults composed by Jinshajiang and Honghe faults. Located at the dextral diagonal region between Honghe and Zhongdian faults, the northwestern region of Yunnan shows a tensile stress field with near EW direction and large graben valleys with near NS direction on the ground due to the dextral slip movements of these two faults and slip of Chuandian Rhombus Block along the SSE direction. The normal features of extension tectonic deformation region can be found in this region. Some inner faults (such as Amaniqing, Xiqinglingbeilu) of Chuanqing block show the character of sinistral shear movement with some components of normal slip movement. As the east boundary of Tibet plateau, Minshan and Longmenshan Mountains form the east wall of the plateau. Contrasting to the moving direction of Chuanqing block, the transition from horizontal movement to vertical movement produced the huge nappe reverse deformation in this region, and formed some front\|Mount compensating press\|sag basins such as Gonggaling, Zhangla and Chengdu. Because of the diversity of slip rate of different boundary faults, some clockwise rotating movement can be found in different sub\|blocks. 展开更多
关键词 TECTONIC deformation block slip SEISMICITY the east borde r of Tibet PLATEAU
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Int’l Cooperation Zone under Construction in Jilin
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作者 Zhu zijun 《China's Foreign Trade》 2012年第6期63-63,共1页
An international cooperative demonstration zone is to be built in Northeast China’s Jilin Province to boost cross-border cooperation in the region, according to a press conference held in Beijing on May 21.
关键词 Jilin INT COOPERATION DEMONSTRATION NORTHEAST bord
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Investigation and control of a Plasmodium falciparum malaria outbreak in Shan Special Region II of Myanmar along the China-Myanmar Border from June to December 2014 被引量:5
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作者 Hui Liu Jian-Wei Xu +9 位作者 Heng-Lin Yang Mei Li Cheng-De Sun Yi-Jie Yin Zhi-Liang Zheng Guang-Yun Zhang Ai-Shui Yu Yong-Hui Yang Chun-Hui Li Shui Ai 《Infectious Diseases of Poverty》 SCIE 2016年第1期277-287,共11页
Background:From 2007 to 2013,intensive control measures reduced malaria burden by 90%along the China-Myanmar border.However,despite these measures a P.falciparum malaria outbreak was reported in the Shan Special Regio... Background:From 2007 to 2013,intensive control measures reduced malaria burden by 90%along the China-Myanmar border.However,despite these measures a P.falciparum malaria outbreak was reported in the Shan Special Region II of Myanmar in June of 2014.Methods:Epidemiological,parasitological and entomological investigations were performed.Dihydroartemisinin piperaquine(DAPQ)was immediately administered to treat parasite positive individuals.Long lasting insecticidal nets(LLIN),indoor residual spraying(IRS)with insecticides and behavior change communication(BCC)were also provided for outbreak control.An embedded efficacy study was conducted evaluating DP.Molecular genotyping via polymerase chain reaction(PCR)was performed on the Kelch gene on chromosome 13.Results:All infections were identified as Plasmodium falciparum by RDT and microscopy.Two fatalities resulted from the outbreak.The attack rate was 72.8%(67/92)and the incidence density rate was 14.2 per 100 person-weeks.The positive rate of rapid diagnostic test(RDT)was 72.2%(65/90)and microscopically-determine parasite rate 42.2%(38/90).Adjusted odds ratio(OR)of multivariate logistic regression analysis for aged<15 years,15–45 years,inappropriate treatment from a private healer and lack of bed nets were 13.51(95%confidence interval,2.21–105.89),7.75(1.48–44.97),3.78(1.30–46.18)and 3.21(1.21–15.19)respectively.In the six surrounding communities of the outbreak site,positive RDT rate was 1.2%(4/328)and microscopically-determine parasite rate 0.6%(2/328).Two light traps collected a total of 110 anopheline mosquitoes including local vectors,An.minimus,An.sinensis and An.maculates.After intensive control,the detection of malaria attacks,parasites and antigen were reduced to zero between July 1 and December 1,2014.The cure rate of P.falciparum patients at day 42 was 94.3%(95%CI,80.8–99.3%).The PCR did not detect K13-propeller mutations.Conclusion:Imported P.falciparum caused the outbreak.Age,seeking inappropriate treatment and lack of bed nets were risk factors for infection during the outbreak.P.falciparum was sensitive to treatment with DAPQ.The integrated measures controlled the outbreak and prevented the spread of P.falciparum effectively.The results of this study indicate that malaria control on the China-Myanmar border,especially among special populations,needs further collaboration between China,Myanmar and international societies. 展开更多
关键词 Malaria outbreak Plasmodium falciparum INVESTIGATION Control Chinese-Myanmar borde
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Au bord du lac. 21septembre1838
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作者 汪玮 陈玮 《法语学习》 2000年第4期14-16,共3页
关键词 维克多·雨果 《Au bord du lac》 《湖畔》 散文阅读 阅读欣赏 法语学习 学习辅导
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MINERALOGY
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《Abstracts of Chinese Geological Literature》 2011年第2期25-30,共6页
20110814 Ding Haihong(State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210093,China);Hu Huan Study on Metamict Zircon from the Koktokay No.3 Granit... 20110814 Ding Haihong(State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210093,China);Hu Huan Study on Metamict Zircon from the Koktokay No.3 Granitic Pegmatite Vein(Acta Mineralogica Sinica,ISSN1000-4734,CN52-1045/P,30(2),2010,p.160-167,5 illus.,2 tables,23 refs.)Key words:metamict minerals,Xinjiang In order to acquire relationships among chemical compositions,structures and metamict degrees of different positions on zircon and evaluate the influence of α-decay on structures of different parts of zircon,in this pater,metamict zircon from the Koktokay No.3 granitic pegmatite,Altai,NW China,was studied by using Electron Microprobe analysis(EPMA)and Raman spectrum analysis.EPMA results revealed that this zircon belongs to hafnian zircon with an evident zonal structure,and the contents of U and Th in the core were higher than those in the border. 展开更多
关键词 ZIRCON NANJING MINERALS TABLES ZONAL belongs borde
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