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Systems Analysis and Design 5th ed.

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Sensitivity analysis on parameter changes in underground mine ventilation systems

丛书名：经典原版书库

2004年

作者： Shelly gary B.

本书全面讨论了系统开发生命周期的方方面面,从商业案例分析、需求建模、企业建模、开发策略、数据设计、用户界面设计、系统架构、系统实施和支持到最新的发展趋势,完美地结合了理论和实践工具

ISBN: (纸本)7111129148

关键词： System analysis.

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Journal of Coal Science & engineering(China) 2011年第3期17卷 251-255页

作者： LI gary KOCSIS Charles HARDCASTLe Steve Mining and Mineral Sciences Laboratories Natural Resources Canada Sudbury P3E 5P5 Canada

A more efficient mine ventilation system, the ventilation-on-demand (VOD) system, has been proposed and tested in Canadian mines recently. In order to supply the required air volumes to the production areas of a mine, operators need to know the cause and effect of any changes requested from the VOD system. The sensitivity analysis is developed through generating a cause and effect matrix of sensitivity factors on given parameter changes in a ventilation system. This new utility, which was incorporated in the 3D-CANVeNT mine ventilation simulator, is able to predict the airflow distributions in a ventilation network when underground conditions and ventilation controls are changed. For a primary ventilation system, the software can determine the optimal operating speed of the main fans to satisfy the airflow requirements in underground workings without necessarily using booster fans and regulators locally. An optimized fan operating speed time-table would assure variable demand-based fresh air delivery to the production areas effectively, while generating significant savings in energy consumption and operating cost.

关键词：矿井通风系统参数变化灵敏度分析 VOD点播系统矿山生产气流分布运行速度敏感性因素

Deadly oasis:Recurrent annihilation of Cretaceous desert bryophyte colonies;the role of solar,climate and lithospheric forcing

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Geoscience Frontiers 2021年第1期12卷 1-12页

作者： Juan Pedro Rodríguez-Lópeza eduardo Barrón Daniel Peyrot gary B.Hughes Department of Geology.Faculty of Science.United Arab emirates University.50009.Al Ain Abu DhabiUnited Arab Emirates Instituto Geológico y Minero de espana(IGMe) Ríos Rosas 23E-28003MadridSpain School of earth and environment University of Western Australia.6101CrawleyWestern AustraliaAustralia Centre for energy Geosciences University of Western Australia.6101CrawleyWestern AustraliaAustralia Physics Department University of CaliforniaSanta BarbaraCA93106USA

Many oases(wet interdunes)are sedimentary systems characterized by high-frequency water-level oscillations,marked changes in salinity and intense biological activity at their *** are considered to be one of the most challenging environments on earth for ecosystem *** dynamic,depositional settings are usually unfavourable for fossilization and subsequent preservation of vegetal *** paper describes bryophyte(liverwort)assemblages occurring in three successive horizons interpreted to represent(i)recurrent early successional phases of biological soil crust colonization of wet interdune margins or(ii)exceptional preservation of floating or riparian liverworts in oasis pond waters associated with a progressive fall of the interdune water *** record of in situ colonization surfaces characterized by delicate(***-free)three-dimensional structures represents an exceptional type of preservation herein associated with a rapid variation in phreatic interdune water level and the subsequent establishment of anoxic and reducing *** occurrence of exceptionally preserved liverwort colonies coincides with the sedimentary record of,at least,three seismite levels in the *** gathered from the site suggests that the water table of the oasis was controlled by a combination of(i)a positive creation of accommodation space due to subsidence associated with movement on syn-sedimentary extensional faults,and(ii)the rise and fall of the oasis water table controlled by the oscillations of the groundwater system due to orbital changes which appear to drive the variability of the climate *** groundwater levels flooded the oasis soil crusts and lead to the exceptional recurrent preservation of liverwort colonies at the oasis ***,considering the hypothesis of floating or riparian liverworts in the oasis pond waters,the fall in the level of the oasis water table placed the floating liverworts in contact with the

关键词： Oasis Cretaceous Liverworts Colonies extensional tectonics Solar cyclicity

THeRe'S NO‘I’IN TeAM BONDING ACTIVITIeS FOR THe WHOLe OFFICe TO eNJOY

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城市漫步（GBA版） 2014年第3期 44-45页

作者： S.e.SMITH gary MAIDMeNT VAN FAN 不详

Team building can be a tedious task,one that's often performed only with a degree of relucta nee and ***,here at That's PRD we thoroughly believe in a good bonding session and have sourced some of the best locations t... 详细信息

关键词： OFFICe thoroughly bonding

Analysis of controls upon channel planform at the First Great Bend of the Upper Yellow River, Qinghai-Tibet Plateau

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Journal of Geographical Sciences 2013年第5期23卷 833-848页

作者： LI Zhiwei WANG Zhaoyin PAN Baozhu DU Jun gary BRIeRLeY YU Guo-an Brendon BLUe State Key Laboratory of Hydroscience and engineering Tsinghua University Beijing 100084 China Changjiang River Scientific Research Institute Wuhan 430010 China School of environment University of Auckland Private Bag 92019 Auckland New Zealand Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

The 270 km long section of the Upper Yellow River at the First Great Bend is comprised of single channel and multiple channel systems that alternate among anastomosing, anabranching, meandering and braided reaches. The sequence of downstream pattern changes is characterized as： anastomosing-anabranching, anabranching-meandering, meandering-braided and braided-meandering. Remote sensing images, DeM data and field investigations are used to assess ahd interpret controls on these reach transitions. Channel slope and bed sediment size are key determinants of transitions in channel planform. Anas- tomosing reaches have a relatively high bed slope （0.86‰） and coarser sediment bed material （d50 = 3.5 mm）. In contrast, meandering reaches have a low slope （0.30‰） and fine sediment bed material （d50 = 0.036 mm）. The transition from a meandering to braided pattern is characterized by an increase in channel width-depth ratio, indicating the important role of bank strength （i.e. cohesive versus non-cohesive versus channel boundaries）. Interestingly, the braided-meandering and meandering-braided transitions are coincident with variable flow inputs from tributary rivers （Baihe and Heihe rivers respectively）. Theoretical analysis of the meandering-braided transition highlights the key control of channel width-depth ratio as a determinant of channel planform.

关键词： Yellow River Source river pattern diversity river pattern transition anastomosing river ana- branching river meandering river braided river

Systematic comparison of hydrogen production from fossil fuels and biomass resources

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International Journal of Agricultural and Biological engineering 2017年第6期10卷 192-200页

作者： Kang Peng gary Morrow Zhang Xiaolei Wang Tipeng Tan Zhongfu Jayant Agarwal Institute of energy economics and environment School of Economics and ManagementNorth China Electric Power UniversityBeijing 102206China School of Mechanical and Aerospace engineering Queen’s University BelfastBelfast BT95AHUnited Kingdom National engineering Laboratory for Biomass Power Generation equipment School of Renewable Energy EngineeringNorth China Electric Power UniversityBeijing 102206China Department of Mechanical engineering College of Engineering RoorkeeUttarakhand 247667India

Fossil fuels are the main energy source to satisfy the worldwide energy ***,the energy demands are increasing and the supply of fossil fuels is decreasing,thus many countries are looking for other fuel *** from the traditional fuels,hydrogen is considered as one of the most promising energy sources due to its intrinsic features such as clean,efficient,safe and *** novel technologies for hydrogen production from renewable sources(such as biomass)becomes a core area for the investigation of hydrogen *** this work,different pathways for hydrogen production including steam reforming,electrolysis,and biomass gasification have been systematically compared in terms of yield and *** comparison is unique since the systematic evaluation was conducted from many aspects for all the hydrogen production pathways,especially those by involving the biomass gasification that still lack of available *** assessment methods involved energy analysis,exergy analysis and economic *** was concluded that steam reforming remains the cheapest method of hydrogen production at 1.748$/kg,however,steam reforming is not an ideal process currently or for the future,gasification and electrolysis remains competitive with high yield but requires relatively high initial and annual *** biomass gasification,though its energy efficiency is lower than steam reforming,it has relatively higher mass yield,demonstrating the feasibility of this process for hydrogen *** for biomass gasification,the selection of correct feedstock is a key to maximize its yield,i.e.a yield of 82.47%is possible with corn stover fed gasification.

关键词： hydrogen production biomass feedstock gasification pyrolysis fossil fuel techno-economic assessment exergy

Analytical chemistry / 6th ed.

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evaluation of regional water security using water poverty index

2004年

作者： gary D. Christian.

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International Journal of Agricultural and Biological engineering 2008年第2期1卷 8-14页

作者： Fu Qiang gary Kachanoski Liu Dong Wang Zilong Department of Renewable Resources University of AlbertaEdmontonT6G2E3Canada College of Water Conservancy and Architecture Northeast Agricultural UniversityHarbin 150030China

Water security is a widely concerned issue in the world nowadays.A new method,water poverty index(WPI),was applied to evaluate the regional water *** state farms in Heilongjiang Province,Northeastern China were selected to evaluate water security status based on the data of 2006 using WPI and mean deviation grading *** method of WPI includes five key indices:resources(R),access(A),capacity(C),utilization(U)and environment(e).each key index further consists of several *** to the results of WPI,the grade of each farm was calculated by using the method of mean deviation ***,the radar images can be protracted of each *** the radar images,the conclusions can be drawn that the WPI values of Farm 853 and Hongqiling are under very safe status,while that of Farm Raohe is under safe status,those of Farms Youyi,597,852,291 and Jiangchuan are under moderate safe status,that of Farm Beixing is under low safe status and those of Farm Shuangyashan,Shuguang and Baoshan are under unsafe *** results from this study can provide basic information for decision making on rational utilization of water resources and regulations for regional water safety guarantee system.

关键词： mean deviation grading method water poverty index water security evaluation weighted average method

Hypoxia promotes growth of stem cells in dental follicle cell populations

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Journal of Biomedical Science and engineering 2011年第6期4卷 454-461页

作者： Yuntao Dai Hongzhi He gary e. Wise Shaomian Yao Department of Comparative Biomedical Sciences School of Veterinary Medicine Louisiana State University Baton Rouge Louisiana 70803 USA.

Adult stem cells (ASC) have been found in many tis-sues and are of great therapeutic potential due to their capability of differentiation. However, ASC comprise only a small fraction of the tissues. In order to use ASC for therapeutic purposes, it is important to obtain relatively pure stem cells in large quantities. Current methods for stem cell purification are mainly based on marker-dependent cell sorting techniques, which have various technical difficulties. In this study, we have attempted to develop novel conditions to favor the growth of the dental follicle stem cells (DFSC) such that the resultant cell populations are enriched in stem cells. Specifically, a heterogeneous dental follicle cell (H-DFC) population containing stem cells and homogenous non-stem cell dental follicle cell population were cultured at 1% or 5% hypoxic conditions. Only the heterogeneous population could increase proliferation in the hypoxic condition whereas the homogenous DFC did not change their proliferation rate. In addition, when the resultant cells from the heterogonous population were subjected to differentiation, they appeared to have a higher capacity of adipogenesis and osteogenesis as compared to the controls grown in the normal at-mosphere (normoxic condition). These hypoxia- treated cells also express higher levels of some stem cell markers. Together, these data suggest that stem cells are enriched by culturing the heterogeneous cell populations in a reduced O2 condition.

关键词： Hypoxia Dental Follicle (DF) Stem Cells Proliferation Gene expression