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Estimating the size and travel distance of Klapperhorn Mountain debris flows for risk analysis along railway, canada

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International Journal of Sediment Research 2008年第3期23卷 275-282页

作者： c. Derek martin Dept. civil and Environmental Engineering University of Alberta Edmonton Alberta Canada T6G 2W2Drs.

Debris flows occurring on Klapperhorn Mountain in the Yellowhead Pass in the canadian Rocky Mountains pose a significant hazard to railway operations at the base of the mountain. The size (volume) and travel distance of these debris flows play an important role in assessing the risk to the railway. GIS analysis, airphoto interpretation together with field work were undertaken on two debris flows located at track mileage 54.0 and 54.3. characteristics of these two debris flow events were analyzed, including debris flow path morphology and event behavior. Their sizes and travel distances were estimated using an empirical-statistical model (UBcDFLOW) under different initiation conditions. Their potential impact on the railway bridge was evaluated using a bridge blockage ratio.

关键词： Debris flow Size Travel distance Railway

Factor of safety of strain-softening slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 473-483页

作者： Hossein Rafiei Renani c.Derek martin Klohn crippen Berger Ltd. VancouverCanada Department of civil and Environmental Engineering University of AlbertaEdmontonCanada

Stability analysis of strain-softening slopes is carried out using the shear strength reduction method and Mohr-coulomb model with degrading cohesion and friction *** e ffect of strain-softening behavior on the slope factor of safety is investigated by performing a series of analyses for various slope geometries and strength *** charts and equations are developed to estimate the factor of safety of strain-softe ning slopes from the results of traditional stability analysis based on perfectly-plastic *** example applications including an open pit mine in weak rock and clay shale slope with daylighting bedding planes are *** results of limit equilibrium analysis and shear strength reduction method with perfectly-plastic models were in close *** perfectly-plastic models with peak strength properties led to overly optimistic results while adopting residual strength properties gave excessively conservative *** shear strength reduction method with a strain-softening model gave realistic factors of safety while accounting for the process of strength degradation.

关键词： Slope stability analysis Factor of safety ratio Shear strength reduction Perfectly-plastic behavior Open pit slope clay shale slope

Output digitization of simple measure-preserving linear systems

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control Theory and Technology 2021年第4期19卷 430-443页

作者： A.DeStefano M.Thitsa c.martin Department of Mathematics and computer Science College of the Holy CrossWorcesterMA 01610USA Department of Electrical and computer Engineering Mercer UniversityMaconGA 31207USA Department of Mathematics and Statistics Texas Tech UniversityLubbockTX 79430USA

We examine three simple linear systems from the viewpoint of ergodic *** digitize the output and record only the sign of the output at integer *** show that even with this minimal output we can recover important information about the *** particular,for a two-dimensional system viewed as a fow on the circle,we can determine the rate of *** then use these results to determine the slope of the trajectories for constant irrational fow on the two-dimensional *** achieve this,we randomize the system by partitioning the state space and only recording which partition the state is in at each integer *** show directly that these systems have entropy ***,we examine two four-dimensional systems and reduce them to the study of linear fows on the two-dimensional torus.

关键词： Ergodic Linear system Observability cantor set

Fit to fight——from military hygiene to wellbeing in the British Army

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Military Medical Research 2020年第4期7卷 482-488页

作者： martin c.M.Bricknell colonel David A.Ross Health and Military Medicine Conflict and Health Research GroupSchool of Security StudiesKing’s College LondonStrand CampusLondon WC2R 2LSUK Parkes Professor of Preventive Medicine Robertson HouseCamberley GU154NAUK

This paper reviews the historical evolution of the language and organization surrounding the health of personnel in the British Army from‘hygiene’through to‘wellbeing’.It starts by considering the health of the army in the midnineteenth century and the emergence of military hygiene as a professional *** continues by looking at advances in military hygiene in the two world *** was replaced by the term‘health’in the 1950 s as the collective noun used by professionals working in this *** unity split when the professions of occupational medicine and public health established separate faculties and training ***,the health issues for the armed forces remain fundamentally *** forward,the term‘wellbeing’is helping to refresh the close relationships between executives,their medical advisers and those within the population of health professions charged with keeping the British Army *** core theme is the collaborations between civil society,executive leadership and medical services in maximizing the health of the military population from recruitment through to life as a veteran.

关键词： Public health Hygiene Occupational medicine

Therapeutic uses of animal biles in traditional chinese medicine:An ethnopharmacological,biophysical chemical and medicinal review

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World Journal of Gastroenterology 2014年第29期20卷 9952-9975页

作者： David Q-H Wang martin c carey Gastroenterology Division Department of MedicineBrigham and Women’s HospitalHarvard Medical School and Harvard Digestive Diseases Center Liver center and Gastroenterology Division Department of MedicineBeth Israel Deaconess Medical CenterHarvard Medical School and Harvard Digestive Diseases Center Division of Gastroenterology and Hepatology Department of Internal MedicineEdward Doisy Research CenterSaint Louis University School of Medicine

Forty-four different animal biles obtained from both invertebrates and vertebrates (including human bile) have been used for centuries for a host of maladies in traditional chinese medicine (TcM) beginning with dog, ox and common carp biles approximately in the Zhou dynasty (c. 1046-256 BcE). Overall, different animal biles were prescribed principally for the treatment of liver, biliary, skin (including burns), gynecological and heart diseases, as well as diseases of the eyes, ears, nose, mouth and throat. We present an informed opinion of the clinical efficacy of the medicinal uses of the different animal biles based on their presently known principal chemical components which are mostly steroidal detergent-like molecules and the membrane lipids such as unesterified cholesterol and mixed phosphatidylcholines and sometimes sphingomyelin, as well as containing lipopigments derived from heme principally bilirubin glucuronides. All of the available information on the ethnopharmacological uses of biles in TcM were collated from the rich collection of ancient chinese books on materia medica held in libraries in china and United States and the composition of various animal biles was based on rigorous separatory and advanced chemical identification techniques published since the mid-20th century collected via library (Harvard’s countway Library) and electronic searches (PubMed and Google Scholar). Our analysis of ethnomedical data and information on biliary chemistry shows that specific bile salts, as well as the common bile pigment bilirubin and its glucuronides plus the minor components of bile such as vitamins A, D, E, K, as well as melatonin (N-acetyl-5-methoxytryptamine) are salutary in improving liver function, dissolving gallstones, inhibiting bacterial and viral multiplication, promoting cardiac chronotropsim, as well as exhibiting anti-inflammatory, anti-pyretic, anti-oxidant, sedative, anti-convulsive, anti-allergic, anti-congestive, anti-diabe

关键词： Bile acids Bile pigments Bilirubinates Liquid crystals Materia medica Mixed micelles Bear bile Ox gallstones Paleo-pharmacology Phospholipids

A new strategy for corrosion protection of porous stainless steel using polypyrrole films

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Journal of Materials Science & Technology 2020年第2期37卷 85-95页

作者： c.Garcia-cabezon c.Garcia-Hernandez M.L.Rodriguez-Mendez F.martin-Pedrosa Materials Engineering E.I.I.Universidad de Valladolid47011 ValladolidSpain UVASENS E.I.I.Universidad de Valladolid47011 ValladolidSpain

In this work,a method to improve the protection against corrosion of porous sintered stainless steel is *** is based on the electrodeposition of polypyrrole(PPy)layers doped with a large size counterion such as dodecylbenzenesulphonic acid(DBSA),a conducting polymer with high corrosion resistance and good *** efficacy of PPy coating depends on the adequate adhesion between the metal substrate and the coating *** protection against corrosion has been tested using 316 L stainless steel(SS)powder sintered at different conditions to evaluate the effect of the sintering atmosphere(nitrogen and vacuum)and cooling rates(furnace and water)on corrosion resistance,while wrought 316 L SS has been used as reference *** addition,two electrochemical deposition techniques have been tested to select the most *** circuit potential evolution,anodic polarization measurements and electrochemical impedance spectra have been used to evaluate corrosion protection in phosphate buffer saline *** has been evidenced that a more homogeneous and stable coating was obtained in the case of porous stainless *** corrosion potential shifted to nobler values and the anodic polarization branch became more *** porous samples have a good passivation performance with a lower stable passive current density and a higher breakdown *** transfer electronic resistance and the impedance module increase more than one order of ***,the porosity of sintered stainless steel is seen as an advantage for the improvement of the adherence of the PPy *** best corrosion protection is found for samples sintered in nitrogen and water-cooled.

关键词： Stainless steel Powder metallurgy Protection corrosion Electrodeposited films Polymer coatings

channeling the water data deluge:a system for flexible integration and analysis of hydrologic data

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International Journal of Digital Earth 2016年第3期9卷 272-299页

作者： Michael P.McGuire martin c.Roberge Jie Lian Department of computer and Information Sciences Towson UniversityTowsonMDUSA Department of Geography and Environmental Planning Towson UniversityTowsonMDUSA

The hydrologic cycle and understanding the relationship between rainfall and runoff is an important component of earth system science,sustainable development,and natural disasters caused by *** this in mind,the integration of digital earth data for hydrologic sciences is an important area of ***,it takes a tremendous amount of effort to perform hydrologic analysis at a large scale because the data to support such analyses are not available on a single system in an integrated format that can be easily ***,the state-of-the-art in hydrologic data integration typically uses a rigid relational database making it difficult to redesign the data model to incorporate new data *** Hydrocloud system incorporates a flexible document data model to integrate precipitation and stream flow data across spatial and temporal dimensions for large-scale hydrologic *** this paper,a document database schema is presented to store the integrated data-set along with analysis tools such as web services for data access and a web interface for exploratory data *** utility of the system is demonstrated based on a scientific workflow that uses the system for both exploratory data analysis and statistical hypothesis testing.

关键词： hydrology data integration cloud-based systems NoSQL NEXRAD precipitation stream flow

Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes

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Journal of Mountain Science 2019年第2期16卷 243-255页

作者： Derek J.martin christopher ELY Beverley c.WEMPLE Department of Geography and Planning Appalachian State University Department of Geography University of Vermont

The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km^2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.

关键词： Bank erosion Páramo Fluvial geomorphology Andes

Identifying coastal towns and small cities in Denmark using global population data to support climate change adaptation

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International Journal of Digital Earth 2020年第9期13卷 1040-1054页

作者： James M.Fitton martin Lehmann David c.Major Department of Planning Aalborg UniversityAalborgDenmark The Earth Institute Columbia UniversityNew YorkNYUSA

coastal settlements face many hazards from climate ***,there has been extensive focus on developing and implementing ***,these efforts have prodominantly centred on larger *** towns and small cities(urban areas between 1000 and 100,000 people)have received little attention,despite experiencing a number of barriers to *** absence of information on the global scale of the adaptation challenge within coastal towns and small cities may have contributed to these settlements being *** paper develops a method that can be used to estimate the numbers,sizes,and locations of coastal towns and small cities worldwide from global population data(Global Human Settlement data).Denmark is used as a pilot for this method with settlements over 1000 people classified with relatively high *** method developed here represents a potentially fruitful approach to supporting coastal adaptation,as coastal towns and small cities are identifiable globally,they can be classified into *** will support an assessment of their risk to coastal hazards,and could facilitate knowledge and practice sharing between similar coastal towns and small cities.

关键词： climate change adaptation global data coastal hazards Denmark small urban areas