检索结果-南通市图书馆

Analysis of coal pillar stability(ACPS): A new generation of pillar design software

International Journal of Mining Science and technology 2019年第1期29卷 87-91页

作者： christopher Mark Zach Agioutantis technical Support Mine Safety and Health Administration Department of Mining Engineering University of Kentucky

thirty years ago, the analysis of longwall pillar stability(ALPS) inaugurated a new era in coal pillar *** was the first empirical pillar design technique to consider the abutment loads that arise from full extraction, and the first to be calibrated using an extensive database of longwall mining case *** was followed by the analysis of retreat mining stability(ARMPS) and the analysis of multiple seam stability(AMSS). these methods incorporated other innovations, including the coal mine roof rating(CMRR), the Mark-Bieniawski pillar strength formula, and the pressure arch loading model. they also built upon ever larger case history databases and employed more sophisticated statistical ***, these empirical methods are used in nearly every underground coal mine in the US. however,the piecemeal manner in which these methods have evolved resulted in some weaknesses. For example,in certain situations, it may not be obvious which program is the best to use. Other times the results from the different programs are not entirely consistent with each other. the programs have also not been updated for several years, and some changes were necessary to keep pace with new developments in mining practice. the analysis of coal pillar stability(ACPS) now integrates all three of the older software packages into a single pillar design framework. ACPS also incorporates the latest research findings in the field of pillar design, including an expanded multiple seam case history data base and a new method to evaluate room and pillar panels containing multiple rows of pillars left in place during pillar *** also includes updated guidance and warnings for users and features upgraded help files and graphics.

关键词： Pillar design Ground control Stability Empirical methods

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

transient elastography improves detection of liver cirrhosis compared to routine screening tests

引用

World Journal of Gastroenterology 2015年第3期21卷 953-960页

作者： thomas Gobel Janine Schadewaldt-tümmers Lucas Greiner christopher Poremba Dieter haussinger Andreas Erhardt Klinik für Gastroenterologie Hepatologie und InfektiologieUniversitatsklinikum Düsseldorf40225 DüsseldorfGermany Klinik für Gastroenterologie Hepatologie und DiabetologiePetrus-Krankenhaus Wuppertal42283 WuppertalGermany Pathologie München-Nord Ernst-Platz-StraBe 280992 MünchenGermany

AIM:to investigate the diagnostic significance oftransient elastography(tE) in a daily routine clinical setting in comparison to clinical signs,laboratory parameters and ***:tE,ultrasound,laboratory parameters and cutaneous liver signs were assessed in 291 consecutive patients with chronic liver disease of various aetiologies who underwent liver biopsy in daily ***:Sensitivity of tE for the detection of liver cirrhosis was 90.4%,compared to 80.1% for ultrasound,58.0% for platelet count and 45.1% for cutaneous liver signs(P th histology).AUROC for tE was 0.760(95%CI:0.694-0.825).Combination of tE with ultrasound increased sensitivity to 96.1% and AUROC to 0.825(95%CI:0.768-0.882).tE correlated with laboratory parameters of cirrhosis progression like albumin(r =-0.43),prothrombin time(r =-0.44),and bilirubin(r = 0.34; P h).Particularly,in patients with Child Pugh score A or normal platelet count tE improved sensitivity for the detection of liver cirrhosis compared to ultrasound by 14.1%(P transient elastography is superior to routine diagnostic tests allowing detection of liver cirrhosis in additional 10%-16% of patients with chronic liver disease that would have been missed by clinical examinations.

关键词： transient elastography Fibroscan Liver cirrhosis Liver disease Chronic hepatitis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wildfire effects on permafrost and soil moisture in spruce forests of Interior Alaska

引用

Journal of Forestry Research 2020年第2期31卷 553-563页

作者： christopher Potter Charles hugny NASA Ames Research Center Moffett FieldCA 94035USA Interior Alaska Wilderness Consultants NenanaAKUSA

In the summer of 2015,hundreds of forest fires burned across the state of *** uncontrolled wildfires near the town of tanana on the Yukon River were responsible for the largest portion of the area burned *** July 2017,field measurements were carried out in both unburned and burned forested areas nearly adjacent to one another,all within 15 miles of the village of *** surveys were used to first visually verify locations of different burn severity classes,(low,moderate,or high),estimated in 2016 from Landsat images(collected before and after the 2015 tanana-area wildfires).Surface and soil profile measurements to 30-cm depth at these same locations were collected for evidence of moss layer and forest biomass *** temperature and moisture content were measured to 30-cm depth,and depth to permafrost was estimated by excavation wherever *** thermal infra-red images of the soil profiles were taken at each site location,and root-zone organic layer samples were extracted for further chemical *** supported the hypothesis that the loss of surface organic layers is a major factor determining post-fire soil water and temperature changes and the depth of permafrost *** the most severely burned forest sites,complete consumption of the living moss organic layer was strongly associated with both warming at the surface layer and increases in soil water content,relative to unburned forest *** temperatures at both 10-cm and 30-cm depths at burned forest sites were higher by 8-10C compared to unburned *** 15 cm,temperatures of unburned sites dropped gradually to frozen levels by 30 cm,while soil temperatures at burned sites remained above 5C to 30-cm *** water content measured at 3 cm at burned sites was commonly in excess of 30%by volume,compared to unburned *** strong correlation between burn index values and depth to permafrost measured across all sites sampled in July 2017 showed tha

关键词： Alaska Landsat Permafrost RdNBR Soil temperature Soil water Wildfire

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Coal bursts in the deep longwall mines of the United States

引用

International Journal of Coal Science & technology 2016年第1期3卷 1-9页

作者： christopher Mark U.S. Mine Safety and health Administration Pittsburgh PAUSA

Coal bursts involve the sudden, violent ejection of coal or rock into the mine workings. they are a particular hazard because they typically occur without warning. During the past 2 years three US coal miners were killed in two coal bursts, following a 6-year period during which there were zero burst fatalities. this paper puts the US experience in the context of worldwide research into coal bursts. It focuses on two major longwall mining coalfields which have struggled with bursts for decades. the Utah experience displays many of the ＂classic＂ burst characteristics, including deep cover, strong roof and floor rock, and a direct association between bursts and mining activity. In Colorado, the longwalls of the North Fork Valley （NFV） also work at great depth, but their roof and floor strengths are moderate, and most bursts have occurred during entry development or in headgates, bleeders, or other outby locations. the NFV bursts also are more likely to be associated with geologic structures and large magnitude seismic events. the paper provides a detailed case history to illustrate the experience in each of these coalfields. the paper closes with a brief discussion of how US longwalls have managed the burst risk.

关键词： Underground mining Coal Burst Longwall Strata control

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Non-invasive transcutaneous electrical stimulation in the treatment of overactive bladder

引用

Asian Journal of Urology 2015年第2期2卷 92-101页

作者： Martin Slovak christopher R.Chapple Anthony t.Barker Department of Medical Physics&Clinical Engineering Sheffield Teaching Hospitals NHS Foundation TrustSheffieldUK Department of Urology Sheffield Teaching Hospitals NHS Foundation TrustSheffieldUK

We reviewed the literature on transcutaneous electrical nerve stimulation(tENS)used as a therapy for overactive bladder(OAB)symptoms,with a particular focus on:stimulation site,stimuli parameters,neural structures thought to be targeted,and the clinical and urodynamic outcomes *** majority of studies used sacral or tibial nerve *** literature suggests that,whilst tENS therapy may have neuromodulation effects,patient are unlikely to benefit to a significant extent from a single application of tENS and indeed clear benefits from acute studies have not been *** long-term studies there were differences in the descriptions of stimulation intensity,strategy of the therapy,and positioning of the electrodes,as well as in the various symptoms and pathology of the ***,most studies were uncontrolled and hence did not evaluate the placebo *** is known about the underlying mechanism by which these therapies work and therefore exactly which structures need to be stimulated,and with what *** is promising evidence for the efficacy of a transcutaneous stimulation approach,but adequate standardisation of stimulation criteria and outcome measures will be necessary to define the best way to administer this therapy and document its efficacy.

关键词： Overactive bladder Posterior tibial nerve stimulation Sites of stimulation Sacral stimulation Sham stimulation methodology Surface electrodes transcutaneous electrical nerve stimulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

MODELING,SIMULAtION,AND OPtIMIZAtION OF SURFACE ACOUStIC WAVE DRIVEN MICROFLUIDIC BIOChIPS

引用

Journal of Computational Mathematics 2010年第2期28卷 149-169页

作者： harbir Antil Roland Glowinski Ronald h.W.hoppe christopher Linsenmann tsorng-Whay Pan Achim Wixforth Department of Mathematics University of Houston Institute of Mathematics University of Augsburg Institute of Physics University of Augsburg

We will be concerned with the mathematical modeling, numerical simulation, and shape optimization of micro fluidic biochips that are used for various biomedical applications. A particular feature is that the fluid flow in the fluidic network on top of the biochips is in- duced by surface acoustic waves generated by interdigital transducers. We are thus faced with a multiphysics problem that will be modeled by coupling the equations of piezoelectricity with the compressible Navier-Stokes equations. Moreover, the fluid flow exhibits a multiscale character that will be taken care of by a homogenization approach. We will discuss and analyze the mathematical models and deal with their numerical solution by space-time discretizations featuring appropriate finite element approximations with respect to hierarchies of simplicial triangulations of the underlying computational domains. Simulation results will be given for the propagation of the surface acoustic waves on top of the piezoelectric substrate and for the induced fluid flow in the microchannels of the fluidic network. the performance of the operational behavior of the biochips can be significantly improved by shape optimization. In particular, for such purposes we present a multilevel interior point method relying on a predictor-corrector strategy with an adaptive choice of the continuation steplength along the barrier path. As a specific example, we will consider the shape optimization of pressure driven capillary barriers between microchannels and reservoirs.

关键词： Microfluidic biochips Mathematical modeling Numerical simulation Shape optimization Multiphysics Multiscale problems.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Patterns of cancer recurrence in localized resected hepatocellular carcinoma

引用

hepatobiliary & Pancreatic Diseases International 2015年第3期14卷 269-275页

作者： Aryavarta MS Kumar Elisha t Fredman christopher Coppa Galal El-Gazzaz Federico N Aucejo May Abdel-Wahab Department of Radiation Oncology 9500 Euclid AveT28 Cleveland ClinicCleveland OH 44195 USA Department of Radiology 9500 Euclid Ave Hb6 Cleveland ClinicCleveland OH 44195 USA Department of hepato-pancreato-biliary & transplant Surgery 9500 Euclid Ave A100Cleveland OH 44195 USA

BACKGROUND： tumor resection in non-metastatic hepato- cellular carcinoma （hCC） patients with adequate liver reserve offers a potential cure, but has a high 5-year recurrence rate. We analyzed the patterns of cancer... 详细信息

关键词： hepatocellular carcinoma patterns of failure partial hepatectomy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CO_(2)Plume Geothermal(CPG)Systems for Combined heat and Power Production:an Evaluation of Various Plant Configurations

引用

Journal of thermal Science 2022年第5期31卷 1266-1278页

作者： SChIFFLEChNER christopher WIELAND Christoph SPLIEthOFF hartmut Chair of Energy Systems TUM School of Engineering and DesignTechnical University of Munich85747 GarchingGermany

CO_(2) Plume Geothermal(CPG)systems are a promising concept for utilising petrothermal resources in the context of a future carbon capture utilisation and sequestration *** geothermal energy has a tremendous worldwide potential for decarbonising both the power and heating *** paper investigates three potential CPG configurations for combined heating and power generation(ChP).the present work examines scenarios with reservoir depths of 4 km and 5 km,as well as required district heating system(DhS)supply temperatures of 70℃ and 90℃.the results reveal that a two-staged serial ChP concept eventuates in the highest achievable net power *** a thermosiphon system,the relative net power reduction by the ChP option compared with a sole power generation system is significantly lower than for a pumped *** net power reduction for pumped systems lies between 62.6%and 22.9%.For a thermosiphon system with a depth of 5 km and a required DhS supply temperature of 70℃,the achievable net power by the most beneficial ChP option is even 9.2%higher than for sole power generation *** second law efficiency for the sole power generation concepts are in a range between 33.0%and 43.0%.the second law efficiency can increase up to 63.0%in the case of a ChP ***,the combined heat and power generation can significantly increase the overall second law efficiency of a CPG *** evaluation of the achievable revenues demonstrates that a ChP application might improve the economic performance of both thermosiphon and pumped CPG ***,the minimum heat revenue required for compensating the power reduction increases with higher electricity *** summary,the results of this work provide valuable insights for the potential development of CPG systems for ChP applications and their economic feasibility.

关键词： deep geothermal energy combined heat and power generation CO_(2)plume geothermal systems petrothermal resources carbon capture utilisation and storage

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

the cross-cutting contribution of the end of neglected tropical diseases to the sustainable development goals

引用

Infectious Diseases of Poverty 2017年第1期6卷 634-653页

作者： Mathieu Bangert David h.Molyneux Steve W.Lindsay christopher Fitzpatrick Dirk Engels Department of Control of Neglected tropical Diseases World Health Organization20 Avenue Appia1211 GenevaSwitzerland Department of Parasitology Liverpool School of Tropical MedicineLiverpoolUK Department of Biosciences Durham UniversityDurhamUK

the Sustainable Development Goals(SDGs)call for an integrated response,the kind that has defined Neglected tropical Diseases(NtDs)efforts in the past *** interventions have the greatest relevance for SDG3,the health goal,where the focus on equity,and its commitment to reaching people in need of health services,wherever they may live and whatever their circumstances,is fundamentally aligned with the target of Universal health *** interventions,however,also affect and are affected by many of the other development areas covered under the 2030 *** such as mass drug administration or the programmatic integration of NtD and WASh activities(SDG6)are driven by effective global partnerships(SDG17).Intervention against the NtDs can also have an impact on poverty(SDG1)and hunger(SDG2),can improve education(SDG4),work and economic growth(SDG8),thereby reducing inequalities(SDG10).the community-led distribution of donated medicines to more than 1 billion people reinforces women’s empowerment(SDG5),logistics infrastructure(SDG9)and non-discrimination against disability(SDG16).Interventions to curb mosquito-borne NtDs contribute to the goals of urban sustainability(SDG11)and resilience to climate change(SDG13),while the safe use of insecticides supports the goal of sustainable ecosystems(SDG15).Although indirectly,interventions to control waterand animal-related NtDs can facilitate the goals of small-scale fishing(SDG14)and sustainable hydroelectricity and biofuels(SDG7).NtDs proliferate in less developed areas in countries across the income spectrum,areas where large numbers of people have little or no access to adequate health care,clean water,sanitation,housing,education,transport and *** scoping review assesses how in this context,ending the epidemic of the NtDs can impact and improve our prospects of attaining the SDGs.

关键词： Neglected tropical diseases Sustainable development goals

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Assessing risks from mining-induced ground movements near gas wells

引用

International Journal of Mining Science and technology 2020年第1期30卷 11-16页

作者： christopher Mark Gregory M.Rumbaugh Mine Safety and health Administration PittsburghPAUSA

the proliferation of unconventional gas well development in the Northern Appalachian coalfields has raised a number of mine safety *** wells,which extract gas from deep shale formations,are characterized by gas volumes and pressures that are significantly higher than those observed at many conventional *** gas is composed largely of methane as well as other *** of planned and actively producing wells penetrate protective coal pillars or barriers within active mine boundaries,including chain pillars located between longwall *** released from a well damaged by mining-induced ground movements could pose a risk to miners by flowing into the mine *** mining-induced ground movements that may cause well damage include conventional subsidence,non-conventional subsidence(*** plane slip),pillar failure,and floor *** paper describes the known risk factors for each of the four failure *** includes a framework that can guide the risk assessment process when mining takes place near gas or oil wells.

关键词： Gas well Subsidence Coal protection pillar Risk matrix Longwall mining

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：