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A case study of the stability of a non-typical bleeder entry system.a. a *** mine

International Journal of mining Science and Technology 2020年第1期30卷 25-31页

作者： T.m.Klemetti m.a.Van Dyke I.B.Tulu D.Tuncay NIOSH Pittsburgh mining Research Division Pittsburgh 15236USA Department of mining Engineering West Virginia UniversityMorgantown 26505USA

Longwall abutment loads are influenced by several factors,including depth of cover,pillar sizes,panel dimensions,geological setting,mining height,proximity to gob,intersection type,and size of the *** does proximity to the gob affect pillar loading and entry condition?Does the gob influence depend on whether the abutment load is a forward,side,or rear loading?Do non-typical bleeder entry systems follow the traditional front and side abutment loading and extent concepts?If not,will an improved understanding of the combined abutment extent warrant a change in pillar design or standing support in bleeder entries?This paper details observations made in the non-typical bleeder entries of a moderate depth longwall panel—specifically,data collected from borehole pressure cells and roof extensometers,observations of the conditions of the entries,and numerical modeling of the bleeder entries during longwall *** primary focus was on the extent and magnitude of the abutment loading experienced due to the extraction of the longwall *** to the layout of the longwall panels and bleeder entries,the borehole pressure cells(BPCs)and roof extensometers did not show much change due to the advancing of the first ***,they did show a noticeable increase due to the second longwall advancement,with a maximum of about 4 m.a.of pressure increase and 5mmof roof *** observations of the conditions showed little to no change from before the first longwall panel extraction began to when the second longwall panel had been advanced more than 915 *** pillar spalling was observed on the corners of the pillars closest to the longwall gob as well as an increase in water in the *** addition to the observations and instrumentation,numerical modeling was performed to validate modeling procedures against the monitoring results and evaluate the bleeder *** Consulting Group’s FLAC3D numerical modeling software was used to evaluate the bl

关键词： Abutment loading Longwall Instrumentation Bore hole pressure cells Pillar loading Yield pillar Bleeder pillar

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A Layman’s Impressions of modern medicine

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中华医学杂志 1916年第1期 92-105页

作者： ROGER S. GBEENE, m.a. Resident Director of the China medical Board of the Rockefeller Foundation

Perhaps the layman who has had an opportunity to see how the modern doctor is prepared for his life work is most impressed with the vastness of the field of knowledge which the well trained physician or surgeon must cover, and the great range of subjects with which he must familiarize himself, with the inevitable result that the period of his education continues long after men engaged in business or even in other learn

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Revealing the seismicity increase in interrelationships in various seismic zones in Uzbekistan as a case study

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Geodesy and Geodynamics 2015年第5期6卷 351-360页

作者： Artifeou T.U. Ibragimov R.S. Ibragimova T.L. mirzaev m.a. Artikov m.T. Institute of Seismology

A new research method was developed to investigate the influence of an increase in seismicity from one zone on the increase in other zones nearby. By applying the developed method to each main seismic zone in Uzbekistan, we specify the external seismic zone activation, which has the greatest im.a.t on activation within the research zone. We also identify each external seismic zone characterized by high seismic activity and large seismic potential that has the greatest im.a.t on each seismic zone in Uzbekistan.

关键词： External seismic zoneInternal seismic zoneSeismicitySeismic energyEarthquakeInterrelationship

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Performance evaluation of a WDm/OCDm based hybrid optical switch utilizing efficient resource allocation

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Chinese Optics Letters 2014年第5期12卷 5-10页

作者： Ahmed Nabih Zaki Rashed Abd-Elnaser A. mohammed Osama m.a. Dardeer Electronics and Electrical Communication Engineering Department Faculty of Electronic EngineeringMenofia University

A hybrid optical switch （HOS） with physical layer of wavelength division multiplexing and optical code division multiplexing （WDm/OCDm） scheme is proposed. An additional feature to the HOS than optical cross connect （OXC） is that the controller can process requests for both circuit establishment and burst scheduling. In our study, the m.a.urement criteria of HOS are the blocking probability, probability of error, and probability of outage. To simplify the analysis, no distinction is made between a circuit in progress and a burst in progress. moreover, a minimum fit （minF） resource allocation strategy is applied in order to increase the bandwidth efficiency and control the multiplexing interference of the OCDm. A 2D markov model for the HOS is presented using the minF strategy. Numerical results reveal that the code parameters and the resource allocation strategy greatly affect the performance. Certain periority can be achieved by assigning shorter codes to high periority users and longer codes to low periority users. Also, the probability of error and outage are reduced bv aonling the minF strategy.

关键词： WDm Performance evaluation of a WDm/OCDm based hybrid optical switch utilizing efficient resource allocation

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Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural Regeneration Research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam m.R.Groh moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.R.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive sum.a.y of mature oligodendrocyte diversity is *** delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the im.a.t of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

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尼日利亚推行教师资格标准的危机：一种悲观主义的视角

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比较教育研究 2009年第11期30卷 32-35,58页

作者：楼世洲 m.a.乔治·加加浙江省人文社会科学重点研究基地浙江师范大学高等教育学研究中心、浙江师范大学非洲教育研究中心浙江金华321004 美国杨百翰大学教育学院

尼日利亚和其他非洲国家一样,独立后一直将发展教育作为国家经济增长和社会发展的基础,积极地实施基础教育普及政策。为了实现基础教育发展目标,尼日利亚在1960年独立后,就试图建立一种国家化的教师资格标准来提高教师的质量。但长期的... 详细信息

尼日利亚和其他非洲国家一样,独立后一直将发展教育作为国家经济增长和社会发展的基础,积极地实施基础教育普及政策。为了实现基础教育发展目标,尼日利亚在1960年独立后,就试图建立一种国家化的教师资格标准来提高教师的质量。但长期的实践表明,要建立一个高标准的教师资格要求在低承载力社会(low-carrying-capacity)是过分的要求,或者说是不适当的要求。事实上,即使在发达国家,要全面地推行教师资格制度也不是一件容易的事情。文章认为,尼日利亚强制性推行最低的教师资格标准和教师认证标准政策,脱离了国家的实际,对提高学生成绩和教育质量难以取得成效。在基础教育教师供给受限条件下,要实施教师资格制度,必须实施有实效的发展策略。

关键词：尼日利亚教师资格制度进展困境

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Supplementary Irrigation and Soil Amendment management with Sorghum on Khor Abu Habil （Sudan）

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Journal of Environmental Science and Engineering 2011年第8期5卷 1079-1083页

作者： m.a. Omer E.m. Alamin Water Harvesting Research Institute Khartoum 13391 Sudan Agricultural Economic and Policy Research Center Khartoum 30 Sudan

This research was conducted for 3 cropping seasons at Elobeid Research Station in Western Sudan. The objectives were to improve the irrigation water and soil management and crop yield by evaluating the response of sorghum crop to different supplementary irrigation regimes and soil amendments management in flood basin irrigated scheme. The existing flood irrigation practice was basically conducive to late planting, weed growth, late season water stress and pest and diseases attack. Four levels of each irrigation regimes and farm yard manure （FYm） treatments arranged in split-plot design were tested. Rainfall, field capacity, irrigation water added, profile water content, plant height, yield components and water use efficiency were m.a.ured. Grain yield was significantly increased （p 〈 0,01） with irrigation treatments where 1919, 1870 and 878 kg/ha were obtained for one, two and no irrigation treatments, respectively. The 3 irrigations treatment has produced relatively lower grain yield （1679 kg/ha）. FYm treatment up to 4-8 t/ha showed increase in grain yield. Water added in 1, 2 and 3 irrigation treatments amounts to 4475, 5302 and 6035 m3/ha, respectively which supplmented the rainfall by 23%, 45% and 65%, respectively. Water use efficiency was greater with 1 and 2 irrigation treatments and 4 t/ha FYm which reached 0.43, 0.35 and 0.28 kg/m3, respectively. The result concludes that providing supplementary irrigation from crop establishment to mid season was found sufficient to improve crop productivity.

关键词： Supplementary irrigation sorghum water stress

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The Ability of Combination of Trichoderma Harzianum.a.d Trichoderma Asperellum Isolates in Controlling Fusarium Rot of Chickpea in Com.a.ison with the Effects of Trichoderma Harzianum

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Journal of Environmental Science and Engineering 2011年第8期5卷 1013-1016页

作者： H.m. Shikhlinski m.a. Akrami Genetic Resources Institute of ANAS Baku AZ1106 Azerbaijan mamagan Payame Noor University （PNU） Tabriz 62664 Iran

In this investigation, the ability of biocontrol agents, Trichoderma harzianum.a.d T. aperellum.a.plied in combination and alone, which had been isolated from soil and root chickpea field were com.a.ed to control of Fusarium solani. These isolates had shown good control of Fusarium solani in in-vitro condition. Chickpea roots were treated with T. harzianum individually and in combination and planted in artificially infested soil with pathogen F. solani. Although all biocontrol agents applied individually reduced disease incidence, treatments as combination, except for T. harzianum （T-4）＋ T. asperellum （T-6） showed more protective effect. Combination of T. harzianum （T-7）＋ T. asperellum （T-5） isolate gave the best control （51.29%） at greenhouse condition.

关键词： Fusarium rot chickpea combination Trichoderma control

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Reliability Analysis of Fluid Leak Detection and Isolation System

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Journal of Energy and Power Engineering 2010年第5期4卷 37-44页

作者： m.a. Djeziri B.Ould Bouamama LAGIS UMR CNRS 8146 Polytech-Lille Avenue Paul Langevin V d＇Ascq 59655 France

Reliability analysis of a leak detection system developed by OSYRIS R＆D is dealed with in this paper. The developed algorithm is based on signal processing theory; and it uses the properties of the cross-correlation function in order to distinguish the fluid leak from.a.various disturbances. Experimental results obtained on different processes, in presence of thermal and hydraulic disturbances, show the advantages and limits of the proposed approach.

关键词： Fault detection and isolation thermo-fluid process signal processing.

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Application of Thermal Cracking mechanism of Chrysene molecule Using Density Functional Theory

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Journal of Chemistry and Chemical Engineering 2013年第1期7卷 1-5页

作者： m.a. Shanshal Q.A.Yousif Department of Chemistry College of Science Baghdad University Baghdad Iraq Department of Chemistry College of Science AI-Qadissya University Al-Qadissya Iraq

Density functional theory calculations were carried out to study the thermal cracking for chrysene molecule to estimate the bond energies for breaking C 10b-C 11, C 11-H 11 and C4a-C 12a bonds as well as the activation energies. It was found that for C 10b-C 11 C11-HI 1 and C4a-C12a reactions, it is often possible to identify one pathway for bond breakage through the singlet or triplet states. Thus, the C 11-H11 and C11-C10b bonds ruptured in triplet state whilst the C12a-C4a in singlet state. Also, it was fond that the activation energy value for C4a-C12a bond breakage is lower than required for C10b-C11 and C11-H11 bonds that enquired the C4a-C12a bond ＂bridge bond＂ is a weaker and ruptured firstly in thermal cracking process. It seems that the characteristic planarity for polyaromatic hydrocarbons is an important factor to acquire the molecule structure the required stability along the reaction paths as well as the full octet rule and Clar＇s n-sextet structure, especially when chrysene molecular lose the property of planarity. The atomic charges supported the observation that the breaking bonds C10b-C11, CI1-H11 and C4a-C12a in triplet or singlet states. The configurations in transition state and the conformation for the end products reaction were explained and discussed.

关键词： DFT chrysene thermal cracking C-C rupture C-H rupture

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