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Retzius-sparing robotic radical prostatectomy

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Asian Journal of Andrology 2020年第2期22卷 149-151页

作者： christopher G Eden Department of Urology The Royal Surrey County HospitalGuildford GU27XXUK

Traditional approach to the prostate during radical prostatectomy(RP)when performed by open,laparoscopic,or robotic means has been from its anterior aspect first and has involved suture ligation and division of the dorsal vein complex(DVC),division of the puboprostatic ligaments,and incision of the endopelvic fascia on either side of the *** steps are necessary to liberate the prostate from its surrounding attachments,even though concern has always existed about the likely association between disruption of these structures and postprostatectomy incontinence(PPI).Although perineal prostatectomy leaves these structures intact,it has failed to become widely accepted because of the small incidence of postoperative fecal incontinence and the difficulty in performing a pelvic lymphadenectomy(PLND)when this is indicated.

关键词： robotic radical steps

In situ nanoscale mapping of electrical and catalytic properties

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National Science Review 2024年第7期11卷 65-66页

作者： christopher S.Kley Helmholtz Young Investigator Group Nanoscale Operando CO2 Photo-Electrocatalysis Helmholtz-Zentrum Berlin für Materialien und Energie GmbH Department of Interface Science Fritz Haber Institute of the Max Planck Society

By enabling the conversion of sustainably-derived electrical energy into chemical energy, electrocatalytic reactions are vital for closing the anthropogenic carbon cycle. A wide array of electrocatalytic reactions have gained extensive attention, including hydrogen evolution（HER）, oxygen evolution（OER）, and CO2electroreduction（CO2RR）.

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

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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

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

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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

Coal bursts in the deep longwall mines of the United States

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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

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

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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

Assessing risks from mining-induced ground movements near gas wells

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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

Buildings and terrain unified-multidimensional dual data structure for GIS

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Geo-Spatial Information Science 2015年第4期18卷 151-158页

作者： Pawel BOGUSLAWSKI christopher GOLD Department of Architecture and the Built Environment University of the West of EnglandFrenchay Campus Coldharbour LaneBristolBS161QYUK School of Computing and Mathematics University of South WalesPontypriddUK Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduChina

3D city models are widely used in many disciplines and applications,such as urban planning,disaster management,and environmental ***,the terrain and embedded objects like buildings are taken into consideration.A consistent model integrating these elements is vital for GIS analysis,especially if the geometry is accompanied by the topological relations between neighboring *** a model allows for more efficient and errorless *** memory consumption is another crucial aspect when the wide area of a city is considered-light models are highly *** methods of the terrain representation using the geometrical-topological data structure-the dual half-edge-are proposed in this *** integration of buildings and other structures like bridges with the terrain is also presented.

关键词： multidimensional modeling GIS data structures

Variations in Isochore Thickness of the Ecca Sediments in the Eastern Cape Province of South Africa,as Deduced from Gravity Models

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1699-1712页

作者： christopher BAIYEGUNHI Oswald GWAVAVA School of Computational Sciences Faculty of Science and AgricultureUniversity of Fort Hare

Gravity modelling was carried out along five profiles that traverse the Eastern Cape Province of South Africa in order to determine the depositional surface and isochore thickness of the Ecca *** models of the subsurface rock density reveal that the Ecca Group has a maximum vertical thickness of about 3215 ± 160 *** maximum depositional surface（elevation）above sea level for the Ecca sediments is about 500 m,whilst the depth below sea level reaches about10000 *** of the isochore thickness maps with the depositional surfaces shows that the sediments in the basement highs were subsided,deformed,eroded and deposited in the basement *** basement highs served as the source area（s） for the sediments in the basement lows,thus basement highs are characterized with thin sediment cover whilst the lows have thick sediment cover.

关键词： ediment isochore thickness depositional surface Ecca Group basement highs and lows