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Technical parameters of drawing and coal-gangue field movements of a fully mechanized large mining height top coal caving working face

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Mining Science and Technology 2009年第5期19卷 549-555页

作者： LIU Chang-you HUANG Bing-xiang wu feng-feng School of Mines State Key Laboratory for Coal Resources and Safe Mining China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China

Under fully mechanized, large mining height top coal caving conditions, the shield beam slope angle of the support increases due to the enlargement of the top coal breaking and caving space. This results in a change of the caving window location and dimensions and, therefore, the granular coal-gangue movement and flows provide new characteristics during top coal caving. The main inferences we draw are as follows. Firstly, after shifting the supports, the caved top coal layer line and the coal gangue boundary line become steeper and are clearly larger than those under common mining heights. Secondly, during the top coal caving procedure, the speed of the coal-gangue flow increases and at the same drawing interval, the distance between the coal-gangue boundary line and the top beam end is reduced. Thirdly, affected by the drawing ratio, the slope angle of the shield beam and the dimensions of the caving window, it is easy to mix the gangue. A rational drawing interval will cause the coal-gangue boundary line to be slightly behind the down tail boom lower boundary. This rational drawing interval under conditions of large mining heights has been analyzed and determined.

关键词： large mining height top coal caving coal-gangue movement field coal caving technical parameters coal caving window

Mode of overlying rock roofing structure in large mining height coal face and analysis of support resistance

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Journal of Central South University 2016年第12期23卷 3262-3272页

作者：吴锋锋刘长友杨敬轩 School of Mines Key Laboratory of Deep Coal Resource of Mining of Ministry of Education(China University of Mining & Technology)

The mining space of large mining height coal face is large,the range of movement and caving of rock strata is large and the stability of supports at coal face is low and damage rate of supports is high,which significantly affects the safe and efficient production of coal *** similar simulation experiment and theoretical analysis,the mode of fractured roofing structure of large mining height coal face and the method of determination of reasonable support resistance of the support was *** shows that the structural mode of "combined cantilever beam – non-hinged roofing – hinged roofing" of the large mining height coal face appears at the roofing of large mining height coal *** supporting factor of caved gangue at the gob is introduced,the calculating equations of the fractured step distance of roofing were derived and conventional calculating method of caved height of roofing was corrected and the method of determination of the length and height of each structural area of the roofing was *** reference to the excavating conditions at Jinhuagong coal mine in Datong minefield,the dimensions of structural areas of the roofing of the coal face were determined and analyzed,and reasonable support resistance of the height coal face was *** selecting Model ZZ13000/28/60 support and with procedures of advanced pre-cracking blasting,the safe production of large mining height coal face was assured.

关键词： large mining height roof structure roof model roof fracturing distance support resistance

Calculation and analysis of stress in strata under gob pillars

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Journal of Central South University 2015年第3期22卷 1026-1036页

作者：杨敬轩刘长友于斌吴锋锋 School of Mines China University of Mining and Technology Key Laboratory of Deep Coal Resource Mining of Ministry of Education(China University of Mining and Technology) Datong Coal Mine Group Company

Aiming at the difficulty in stress analysis for strata under pillars with actual bearing conditions, an approach was proposed to apply multi-sectional linear approximation to the characteristic curves of pillar loads, and stress of strata was calculated under pillars with linear load by calculation method for uniform load. This approach leads to a rapid analyzing method for strata stress under pillars with any form of loads. Through theoretical analysis, strata stress expressions for pillars under linear bearing conditions are obtained. In addition, two concepts, stress increase factor and stress factor, are proposed for the approximate analysis of strata stress by uniform load approximation method. It is also found that the stress increase factor of strata is related to the strata stress factor and the ratio of the minimum load on the pillar' two ends to the maximum one; and the distribution features of stress factors and the sizes of their influencing areas in strata influenced by overlying pillars are obtained. Combining with the gob pillar conditions of Jurassic coal seam in Tongxin Coal Mine, it is demonstrated that the results obtained by stress distribution analysis of the strata stress in non-influencing areas of pillars with linear bearing through uniform load approximation are in basic accordance with the results obtained for pillars under linear bearing condition. Therefore, it is feasible and accurate to calculate stress in non-influencing area in strata under pillars with linear bearing condition by uniform load calculation method.

关键词： gob pillars pillar load stress increase factor stress factor strata stress

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang feng Gao Yu-Gui Peng Peng wu Zong-Lin Li Xue-feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Superiority of metastatic lymph node ratio to the 7th edition UICC N staging in gastric cancer

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World Journal of Gastroenterology 2011年第46期17卷 5123-5130页

作者： Long-Bin Xiao Jian-Xing Yu Wen-Hui wu feng-feng Xu Shi-Bin Yang Department of Gastrointestinal-pancreatic Surgery the First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong Province China

AIM:To compare and evaluate the appropriate prog-nostic indicators of lymph node basic staging in gastric cancer patients who underwent radical ***:A total of 1042 gastric cancer patients who underwent radical resection and D2 lymphadenectomy were staged using the 6th and 7th edition International Union Against Cancer(UICC)N staging methods and the metastatic lymph node ratio(MLNR)***-mogeneity,discriminatory ability,and gradient mono-tonicity of the various staging methods were compared using linear trend χ2,likelihood ratio χ2 statistics,and Akaike information criterion(AIC)*** area under the curve(AUC)was calculated to compare the predictive ability of the aforementioned three stag-ing ***:Optimal cut-points of the MLNR were cal-culated as MLNR0(0),MLNR1(0.01-0.30),MLNR2(0.31-0.50),and MLNR3(0.51-1.00).In univariate,multivariate,and stratified analyses,MLNR staging was superior to the 6th and 7th edition UICC N stag-ing *** staging had a higher AUC,higher linear trend and likelihood ratio χ2 scores and lower AIC values than the other two staging ***:MLNR staging predicts survival after gastric cancer more precisely than the 6th and 7th edi-tion UICC N classif ications and should be considered as an alternative to current pathological N staging.

关键词： Gastric cancer Metastatic lymph node ratio Prognosis

Pretreatment neutrophil-to-lymphocyte and platelet-to- lymphocyte ratios do not predict survival in patients with cervical cancer treated with neoadjuvant chemotherapy and radical hysterectomy

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Chinese Medical Journal 2013年第8期126卷 1464-1468页

作者： WANG Dan wu Ming feng feng-zhi HUANG Hui-fang YANG Jia-xin SHEN Keng XIANG Yang Department of Obstetrics and Gynecology Peking Union McdicalCotlege Hospital Peking Union Medical College and ChineseAcademy of Medical Sciences Beijing 100730 China

Background A few inflammatory markers were studied to evaluate their possible prognostic roles in various cancers. The neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are hypothesized to reflect the systemic inflammation. The objective of the present study was to investigate whether or not the pretreatment neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio can predict the survival of patients with cervical cancer treated with neoadjuvant chemotherapy and radical hysterectomy. Methods We performed a retrospective study on cervical cancer patients （FIGO stage Ib2-11b） who had undergone neoadjuvant chemotherapy and radical hysterectomy at Peking Union Medical College Hospital between January 1999 and December 2010. Data on demographics, clinical prognostic markers and histopathology were collected and analyzed. Univariate and multivariate analyses for prognostic factors were performed. Results A total of 111 patients were identified. The median neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios were 2.4 and 142.2, respectively. Overall survival and progression-free survival were neither significantly different between patients with high and low neutrophil-to-lymphocyte ratio （P=0.149 and P=0.108） nor in high and low platelet-to-lymphocyte ratio （P=0.336 and P=0.510）. On multivariate analysis, lymph node status （P=O.O00 and P=-O.O07） and lymphovascular space involvement （P=0.001 and P=0.001） were independent prognostic factors of progression-free survival and overall survival. Conclusions Lymph node status and lymphovascular space involvement were found to be independent prognostic factors for patients with cervical cancer who underwent neoadjuvant chemotherapy and radical hysterectomy. The pretreatment neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios seemed not to predict the survival of patients with cervical cancer treated with neoadjuvant chemotherapy and radical hysterectomy.

关键词： cervical cancer, neoadjuvant chemotherapy radical hysterectomy neutrophil-to-lymphocvte ratio:plutclet-to-lymphcyte ratio

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“全寿期费用”管理在ITER项目中的应用

核科学与工程 2013年第3期33卷 287-292页

作者：邢超吴凤凤中国国际核聚变能源计划执行中心北京100038 核工业标准化研究所北京100091

"全寿期费用"管理是一种全新管理理念和方法,运用"全寿期费用"对国际热核实验堆计划进行管理,实现了对国际热核实验堆计划的成本控制以及与其他影响因素的平衡,今后在工程管理中应强化系统工程理念,做到评估和管理并重,强化信息系统在... 详细信息

"全寿期费用"管理是一种全新管理理念和方法,运用"全寿期费用"对国际热核实验堆计划进行管理,实现了对国际热核实验堆计划的成本控制以及与其他影响因素的平衡,今后在工程管理中应强化系统工程理念,做到评估和管理并重,强化信息系统在费用管理中的应用,能有效提高工程管理水平。

关键词：全寿期费用国际热核实验堆计划管理

大科学工程项目管理实施借鉴——以ITER项目为例

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核科学与工程 2017年第3期37卷 341-347页

作者：邢超吴凤凤中国国际核聚变能源计划执行中心北京100038 核工业标准化研究所北京100091

国际热核聚变实验堆(ITER)计划是目前全球规模最大、影响最深远的,也是我国第一次以平等身份参与的国际大科学合作项目。ITER计划是将最先进的管理理念、科学的管理组织模式和现代化的管理工具充分融合的国际大科学工程,对ITER计划项目... 详细信息

国际热核聚变实验堆(ITER)计划是目前全球规模最大、影响最深远的,也是我国第一次以平等身份参与的国际大科学合作项目。ITER计划是将最先进的管理理念、科学的管理组织模式和现代化的管理工具充分融合的国际大科学工程,对ITER计划项目组织管理的研究能够为我国科技项目管理实施提供借鉴。通过对ITER计划项目组织管理的研究,总结了ITER项目组织管理的四大特点,并基于与当前大科学工程管理理念和管理方法的比较,从系统论、控制论和信息论等管理理论的角度,分析了大科学工程组织实施特性在ITER项目中的应用,进而结合我国科技工作的历史、特点和现状,提炼出我国科技计划项目实施可借鉴的管理方法和经验,包括系统规划总体设计、严格的过程控制、积极有效的过程信息反馈、适度的模块化组织分工。

关键词：大科学工程项目管理 ITER计划系统论过程管理

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries