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There has been a worldwide trend to increase axle loads and train speeds. This means that railway track degradation will be accelerated, and track maintenance costs will be increased significantly. There is a need to investigate the consequences of increasing traffic load. The aim of the research is to develop a model for the analysis of physical degradation of railway tracks in response to changes in traffic parameters, especially increased axle loads and train speeds. This research has developed an integrated track degradation model (ITDM) by integrating several models into a comprehensive framework. Mechanistic relationships for track degradation hav~ ?een used wherever possible in each of the models contained in ITDM. This overcc:mes the deficiency of the traditional statistical track models which rely heavily on historical degradation data, which is generally not available in many railway systems. In addition statistical models lack the flexibility of incorporating future changes in traffic patterns or maintenance practices. The research starts with reviewing railway track related studies both in Australia and overseas to develop a comprehensive understanding of track performance under various traffic conditions. Existing railway related models are then examined for their suitability for track degradation analysis for Australian situations. The ITDM model is subsequently developed by modifying suitable existing models, and developing new models where necessary. The ITDM model contains four interrelated submodels for rails, sleepers, ballast and subgrade, and track modulus. The rail submodel is for rail wear analysis and is developed from a theoretical concept. The sleeper submodel is for timber sleepers damage prediction. The submodel is developed by modifying and extending an existing model developed elsewhere. The submodel has also incorporated an analysis for the likelihood of concrete sleeper cracking. The ballast and subgrade submodel is evolved from a concept developed in the USA. Substantial modifications and improvements have been made. The track modulus submodel is developed from a conceptual method. Corrections for more global track conditions have been made. The integration of these submodels into one comprehensive package has enabled the interaction between individual track components to be taken into account. This is done by calculating wheel load distribution with time and updating track conditions periodically in the process of track degradation simulation. A Windows-based computer program ~ssociated with ITDM has also been developed. The program enables the user to carry out analysis of degradation of individual track components and to investigate the inter relationships between these track components and their deterioration. The successful implementation of this research has provided essential information for prediction of increased maintenance as a consequence of railway trackdegradation. The model, having been presented at various conferences and seminars, has attracted wide interest. It is anticipated that the model will be put into practical use among Australian railways, enabling track maintenance planning to be optimized and potentially saving Australian railway systems millions of dollars in operating costs.

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Campylobacter jejuni and C. coli are the leading causes of human bacterial gastroenteritis in developed countries. Most human Campylobacter infections are sporadic and a seasonal peak in the distribution of infections can be seen in the summer months in several countries, including Finland. A variety of risk factors for Campylobacter infections have been identified; handling and eating poultry, drinking unpasteurized milk, contact with domestic animals, and travelling abroad. However, the relative importance of the different risk factors in sporadic cases of Campylobacter infection remains unknown. In most cases, the infection is self-limiting and no specific treatment is required. Campylobacter enteritis can cause a wide range of complications, including reactive arthritis (ReA) that is reported in 1-5% of the cases. Seven clinical microbiology laboratories serving different geographical areas of Finland, participated in this multi-centre study, conducted during a seasonal peak in 2002. In a matched case-control study, domestically-acquired sporadic Campylobacter infections from three geographical areas were collected. The final study comprised 100 cases and 137 controls. Risk factors for sporadic domestically-acquired Campylobacter infections were identified on the basis of a questionnaire; swimming in natural waters was found to be a novel risk factor for Campylobacter infection. Other independent risk factors were tasting or eating raw or undercooked meat and drinking untreated water from a dug well. The role of bacterial strain and host characteristics are not fully understood in Campylobacter infections. Exposure factors, demographical characteristics, and the serotype of the Campylobacter isolate may affect the severity of the enteritis. This cross-sectional study comprised 114 patients with C. jejuni enteritis, diagnosed in three clinical microbiology laboratories; most of the patients had participated in the previous case-control study. Swimming was associated with age ≤ 5 years and serotype Pen 6,7 was found significantly more often among patients reporting swimming. The geographical distribution among serotypes varied; serotype Pen 4-complex appeared more often in patients from urban areas and serotype Pen 21 among patients from more rural areas. Thus, risk factors and sources of infection for C. jejuni infection may vary among individuals depending on age and geographical location. The in vitro susceptibilities of C. jejuni and C. coli strains isolated from patients infected abroad (85 strains) or domestically (393 strains) revealed that susceptibility to erythromycin is still high, even among isolates of foreign origin. However, the novel antimicrobial agent telithromycin did not offer any advantage over erythromycin; isolates with high minimal inhibitory concentrations (MICs) for erythromycin also showed reduced susceptibility to telithromycin. Reduced susceptibility to fluoroquinolones was detected almost exclusively among isolates of foreign origin and half of these isolates with high MICs for fluoroquinolones also showed elevated MICs for doxycycline. Questionnaires concerning complications associated with C. jejuni enteritis were sent to patients two months after becoming ill; 201 patients from seven different geographical areas were included in the study. Musculoskeletal complications after C. jejuni infection were commonly reported by patients (39%). The incidence of classical ReA was 4% and that of Achilles enthesopathy and/or heel pain 9%. Other C. jejuni-associated reactive joint symptoms were commonly reported, however, due to their milder nature seldom seen and diagnosed by a physician. The severity of the enteritis may predict further complications; stomach ache during enteritis was connected to the development of later joint pain. Early antimicrobial treatment, within two days from the start of symptoms, shortened the duration of diarrhoea by two days but did not prevent later musculoskeletal complications. Campylobacter is an important human enteropathogen and causes a significant burden of illness. As the incidence of Campylobacter infections is high, the importance of the infection and the occurrence of complications will increase. This stresses the importance of understanding the risk factors for acquiring Campylobacter infection and how bacterial strain and host characteristics may affect the risk for infection. The role of antimicrobial treatment for acute Campylobacter enteritis seems to be marginal and should be used restrictively.

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Extreme vibration has been reported for small, high speed craft in the maritime sector, with performance and health threatening effects on boat operators and crew. Musculoskeletal injuries are an enduring problem for high speed craft passengers. Spinal or joint injuries and neurological disorders may occur from repetitive pounding over rough water, continued vibration and single impact events. The risk from whole body vibration (WBV) induced through the small vessels mainly depends on time spent on the craft, which can’t be changed in a military scenario; as well as the number of shocks and jolts, and their magnitude and frequency. In the European Union for example, physical agents directives require all employers to control exposure to a number of physical agents including noise and vibration. The EC Vibration Directive 2002/44/EC then sets out regulations for the control of health and safety risks from the exposure of workers to hand arm vibration (HAV) and WBV in the workplace. Australia has exposure standards relating to WBV, AS 2670.1-2001 – Evaluation of human exposure to whole body vibration. This standard is identical to the ISO 2631-1:1997, Mechanical vibration and shock – Evaluation of human exposure to whole-body vibration. Currently, none of the jurisdictions in Australia have specific regulations for vibration exposures in workplaces. However vibration is mentioned to varying degrees in their general regulations, codes of practice and guidance material. WBV on high speed craft is normally caused by “continuous 'hammering' from short steep seas or wind against tide conditions. Shock on High Speed Craft is usually caused by random impacts. Military organisations need the knowledge to make informed decisions regarding their marine operations, compliance with legislation and potentially harmful health effects, and develop and implement appropriate counter-measures. Marine case studies in the UK such as published MAIB (Marine Accident Investigation Branch) reports show injuries that have occurred in operation, and subsequent MCA (Maritime Coastguard Agency) guidance is provided (MGN 436 (M+F), WHOLE-BODY VIBRATION: Guidance on Mitigating Against the Effects of Shocks and Impacts on Small Vessels. MCA, 2011). This paper proposes a research framework to study the origin, impact and pathways for prevention of WBV in small, high speed craft in a maritime environment.

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Viral hepatitis is caused mainly by infection with one of the five hepatitis viruses, which use the liver as their primary site of replication. Each of these, known as hepatitis A through E viruses (HAV to HEV), belong to different virus families, have unique morphology, genomic organization and replication strategy. These viruses cause similar clinical manifestations during the acute phase of infection but vary in their ability to cause chronic infection. While HAV and HEV cause only acute disease with no chronic sequelae, HBV, HCV and HDV cause varying degrees of chronicity and liver injury, which can progress to cirrhosis and liver cancers. Though specific serological tests are available for the known hepatitis viruses, nearly 20% of all hepatitis cases show no markers. Antiviral therapy is also recommended for some hepatitis viruses and a preventive vaccine is available only for hepatitis B. More research and public awareness programmes are needed to control the disease. This review will provide an overview of the hepatitis viruses and the disease they cause.

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This report to the Thames Water Authority and Central Water Planning Unit is on research carried out in conjunction with the Stage 1 Group Pumping Test of five boreholes in the upper Lambourn Group for a period of three months in September, October and November 1975. The aim of the study was to assess the ecological effects of the pumpin g of five bore-holes in the upper Lambourn. That is, to determine how the seasonal sequence of ecological events in the river differed from what would hav e occurred had no pumping taken place. Since this 'experiment' has no control it is not possible to make a direct assessment. Nevertheless, by careful monitoring of ecological events before, during and after the pumping it is possible to document changes in th e river and by reference to the data already available for the Rive r Lambourn, normal seasonal changes in the flora and fauna can be separated from changes which may be attributable to the pumping and subsequent events.

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本文提出了基于机械臂关节驱动力矩约束方程规划其关节最优运动轨迹的一种有效方法.该方法运用矩阵范数理论简化机械臂的动力学约束方程;在机械臂的关节空间内采用归一化的无因次量运用非线性规划法优化其运动轨迹.将所规划的无因次量轨迹方程作为机械臂产生实际运动轨迹的发生器,通过给定机械臂各运动段的起始和终止关节坐标,由系统的动力学约束方程计算出整个运动段所允许的最短运行时间,即生成所期望的运动轨迹.本文的轨迹规划方法计算效率高,可用于在线轨迹规划,文中通过算例证实了该方法的实用性.

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Längs de finländska vattendragen och den finländska havskusten har identifierats 21 områden med betydande översvämningsrisk. För varje område med betydande översvämningsrisk har utarbetats en plan för hantering av översvämningsrisker. Den här planen för hantering av översvämningsrisker i Helsingfors och Esbo kustområde innehåller mål och åtgärder för att minimera översvämningsriskerna i huvudstadsregionens strandområden och i den närmaste skärgården. I gruppen som utsetts för att utarbeta planen har ingått företrädare för Nylands förbund, städerna Helsingfors och Esbo, Helsingfors och Nylands räddningsverk samt NTM-centralen i Nyland. Dessutom har Samkommunen Helsingforsregionens miljötjänster HRM deltagit i arbetet i egenskap av expert. Viktiga intressentgrupper har hörts enligt behov. Strandområdena i Helsingfors och Esbo har en mångformig natur som varierar från branta klippstränder till vassbevuxna och grunda havsvikar. En del av bäckarna som mynnar ut i havet från de låglänta landskapen når sig långt in i landet vilket gör att det område som påverkas av havsöversvämningar sträcker sig till och med flera kilometer från kusten. Strandområdena i huvudstadsregionen karaktäriseras av en allt tätare bosättning. I närheten av kusten finns utöver bosättning även bland annat flera industri- och samhällsteknikobjekt, låglänta vägar och hamnar. Därtill är underjordiska utrymmen och tunnlar typiska drag för Helsingfors. Målet med hanteringen av översvämningsriskerna är bland annat att trygga bostadsbyggnader, objekt som är svåra att evakuera, samhällsteknikstrukturer, viktiga trafikförbindelser, hamnar, objekt som är farliga för miljön, kulturarvsobjekt och annat byggnadsbestånd om havsvattenståndet stiger. Därtill har man bland annat som mål att minimera egendomsskadorna och att beakta klimatförändringen i det översvämningssäkra byggandet. Man strävar mot målen genom beredskap samt genom åtgärder såväl under som efter översvämningen. Åtgärderna strider inte mot målen för vattenvården. En av de viktigaste åtgärderna som minskar översvämningsrisken i Helsingfors och Esbo kustområde är beaktandet av översvämningsområden och klimatförändringen i planeringen av markanvändningen. Utgångspunkten är att man bör undvika byggande i områden med översvämningsrisk och vid placeringen av funktioner bör man beakta rekommendationerna för lägsta grundläggningsnivå. I fråga om riskobjekt bör man säkerställa att det finns uppdaterade och fungerande beredskapsplaner. Förutsättningarna för invånarnas egen beredskap ska förbättras bland annat genom ökad medvetenhet om översvämningar. I planen identifieras också flera regionala och lokala skyddsbehov.

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Regional structural analysis of the Timmins area indicates four major periods of tectonic deformation. The DI deformation is characterized by a series of isoclinal FI folds which are outlined in the study area by bedding, pillow tops and variolitic flows. The D2 deformation developed the Porcupine Syncline and refolded the Fl folds about a NE. axis. A pervasive S2 foliation developed during low grade (greenschist) regional metamorphism associated with the D2 deformation. The S2 foliation developed south of the Destor-Porcupine Break. The third phase of tectonic D3 deformation is recognized by the development of a S3 sub-horizontal crenulation cleavage which developed on the plane of the S2 foliation. No meso scopic folds are associated with this deformation. The 8 3 crenulation cleavage is observed south of the Destor-Porcupine Break. The D4 tectonic deformation is recorded as a subvertical S4 crenulation cleavage which developed on the plane of the S2 foliation and also offsets the S3 crenulation cleavage. Macroscopic F4 folds have refolded the F2 axial plane. No metamorphic recrystallization is associated with this deformation. The S4 crenulation cleavage is observed south of the Destor-Porcupine Break. Petrographic evidence indicates that the Timmins area has been subjected to pervasive regional low grade (greenschist) metamorphism which has recrystallized the original mineralogy. South of the study are~ the Donut Lake ultramafic lavas have been subjected to contact medium grade (amphibolite facies) metamorphism associated with the intrusion of the Peterlong Lake Complex. The Archean volcanic rocks of the Timmins area have been subdivided into komatiitic, tholeiitic and calcalkaline suites based on Zr, Ti0 2 and Ni. The three elements were used because of their r e lative immobility during subsequent metamorphic events. Geochemical observations in the Timmins area indicates that the composition of the Goose Lake and Donut Lake Formations are a series of peridotitic, pyroxenitic and basaltic komatiites. The Lower Schumacher Formation is a sequence of basaltic komatiites while the upper part of the Lower Schumacher Formation is an intercalated sequence of basaltic komatiites and low Ti0 2 tholeiites. The variolitic flows are felsic tholeiites in composition and geochemical evidenc e sugg ests that they developed as a n immiscible splitting of a tholeiitic magma. The Upper Schumacher Formation is a sequence of tholeiitic rocks dis p laying a mild iron enrichment. The Krist and Boomerang Formations are the felsic calc-alkaline rocks of the study area which are characteristically pyroclastic. The Redstone Fo rmation is dominantly a calc-alkali ne sequence of volcani c rocks whose minor mafic end me mbers exposed in 1t.he study hav e basaltic komatiitic compositions. Geochemical evidence sugges ts that the Keewatin-type se dimentary rocks have a composition similar to a quartz diorite or a granodiorite. Fi e l d obs ervations and petrographic evidence suggests that they were derived fr om a distal source and now repr esent i n part a turbidite sequence. The Timiskaming-type sedimentary rocks approach the c omp osi t ion of the felsic calc-alkaline rocks of the study area . The basal conglomerate in the study are a sugge s ts that th e uni t was derived fr om a proximal source. Petrographic and ge ochemical evidence suggests that the peridotitic and pyroxenitic komatiites originated as a 35-55% partial melt within the mantle, in excess of 100 Km. depth. The melt ros e as a diapir with the subsequent effusion of the ultramafic lavas, The basaltic komatiites and tholeiitic rocks originated in the mantle from lesser degrees of partial melting and fractionated in low pressure chambers. Geochemical evidence suggests a "genetic link" between the basaltic komatiites and tholeiites, The calc-alkaline rocks developed as a result of the increa.se In PO in the magma chamber. The felsic calcalkaline rocks are a late stage effusion possibly the last major volcanic eruptions in the area.

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Conoc iendo la impor tancia del sector asegurador como parte de la base de l sistema financiero de un país, consideram os de gran importancia realizar un estudio que permita establecer la situac ión actual y que posic ión debe tomar el sector asegurador, para enfrent ar escenarios futuros en el corto, mediano y lar go plazo, delimitando las tendencias del me rcado y del entorno, para así crear posibles es trategias encaminadas a tornar a favor las si tuaciones adversas. Con el transcurso de los años ha evolucionado el concepto de riesgo para las Personas y a que estas han tomado conciencia de la inherencia de éste en la vida cotidiana, esto denot a el surgim iento de empresas preocupadas por satisfacer las necesidades y exigenc ias de este sector.

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Background The objectives were to estimate the prevalence of hepatitis A among children and adolescents from the Northeast and Midwest regions and the Federal District of Brazil and to identify individual-, household- and area-levels factors associated with hepatitis A infection. Methods This population-based survey was conducted in 20042005 and covered individuals aged between 5 and 19 years. A stratified multistage cluster sampling technique with probability proportional to size was used to select 1937 individuals aged between 5 and 19 years living in the Federal capital and in the State capitals of 12 states in the study regions. The sample was stratified according to age (59 and 10- to 19-years-old) and capital within each region. Individual- and household-level data were collected by interview at the home of the individual. Variables related to the area were retrieved from census tract data. The outcome was total antibodies to hepatitis A virus detected using commercial EIA. The age distribution of the susceptible population was estimated using a simple catalytic model. The associations between HAV infection and independent variables were assessed using the odds ratio and corrected for the random design effect and sampling weight. Multilevel analysis was performed by GLLAMM using Stata 9.2. Results The prevalence of hepatitis A infection in the 59 and 1019 age-group was 41.5 and 57.4, respectively for the Northeast, 32.3 and 56.0, respectively for the Midwest and 33.8 and 65.1 for the Federal District. A trend for the prevalence of HAV infection to increase according to age was detected in all sites. By the age of 5, 31.5 of the children had already been infected with HAV in the Northeast region compared with 20.0 in the other sites. By the age of 19 years, seropositivity was 70 in all areas. The curves of susceptible populations differed from one area to another. Multilevel modeling showed that variables relating to different levels of education were associated with HAV infection in all sites. Conclusion The study sites were classified as areas with intermediate endemicity area for hepatitis A infection. Differences in age trends of infection were detected among settings. This multilevel model allowed for quantification of contextual predictors of hepatitis A infection in urban areas.

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Inom ramen för projektet Energi- och miljökompetenscentrum vid Högskolan Dalarna haren kortare förstudie kring tekniken som används av Timber Tower GmbH för högavindkrafttorn i trä gjorts. Huvudsyftet med studien har varit att titta närmare på teknikenoch dess potential för svensk landbaserad vindkraft samt utreda vad detta kan innebära förregionen.Trenden för landbaserad vindkraft i skogsmiljö går mot allt högre torn. Skogsmiljön gör attden marknära turbulensen och vindgradienten blir större än över t.ex. hav vilket gör detmer föredelaktigt att använda högre torn.Tekniken som Timber Tower GmbH använder är att bygga tornet på plats med en koniskhålstomme av plana paneler av korslimmat limträ (som annars främst används vidbyggnation av höga hus med massivträstomme). Tekniken är skyddad av ett flertalpatentansökningar varav minst en är beviljad.Vid en jämförelse mellan trätorn och svetsade ståltorn (som är den dominerandetorntekniken idag) kan det konstateras att trätornstekniken är ekonomiskt intressant.Framförallt blir trätornen mer intressanta i jämförelse med ståltornen vi ökande höjder (>100 m) pga. dess transportfördelar. Vidare bör det nämnas att de torntekniker somanvänds idag vid höjder runt 140 m och högre främst är fackverkstorn i stål ochhybridtorn med en hög bas av förspänd betong och övre delen i stål.Då ett typgodkännande av ett vindkraftverk gäller torn och turbin är det i praktiken alltidturbintillverkaren som prissätter och levererar ett komplett vindkraftverk. Medutgångspunkt i regeringens planeringsram för svensk vindkraftutbyggnad (20 TWh/årlandbaserad vindkraft 2020) kan dock marknadsvärdet för torn uppskattas till 2-3 miljarderkr/år fram till 2020. För trätorn motsvarar detta en årlig potentiell volym på ca 190 000 m3.Slutsatsen i denna korta studie är att det är tekniskt möjligt att designa ett trätorn i rimligadimensioner för en 2-3 MW turbin med navhöjd ca 140 m och att detta sannolikt även ärekonomiskt intressant. Då ett trätorn blir något lättare än motsvarande ståltorn går det åtmindre energi för att göra ett trätorn. Hur mycket mindre är dock osäkert pga. den storaspridningen i siffror för energiåtgång för stålproduktion och i praktiken blir skillnadenäven leverantörsberoende. Eftersom andelen förnyelsebar energi är betydligt större vidtillverkningen av materialet för trätornen kommer trätornet att ge en betydande sänkningpå utsläppt CO2e/kWhel jämfört med motsvarande verk med ståltorn. Ett annat argumentför trätorn är förenklade transporter jämfört med t.ex. svetsade ståltorn eller hybridtornmed prefabricerade betongelement.Om tekniken etableras kan det i förlängningen leda till en regional påverkan i form av ökatlokalt innehåll i vindkraftprojekten t.ex. genom ökade råvaruleveranser (eg. sågat ochtorkat virke), lokal produktion av korslimmat limträ eller exempelvis bildande avspecialiserade montagefirmor. Det största hindret för tekniken just nu är dessmarknadsintroduktion och acceptans samt typgodkännande tillsammans med en för svenskmarknad intressant turbinleverantör. För att få acceptans för tekniken krävs byggande ochutvärdering av minst ett verk med trätorn. En intressant storlek för marknaden är en 2-3MW turbin med navhöjd ca 140 m. Ett sådant verk skulle i så fall få det högstavindkrafttornet i Sverige och sannolikt det högsta vindkrafttornet i trä i världen. Byggandetav ett första verk med trätorn skulle sannolikt även kräva ett behov av stödfinansiering föratt täcka en projektörs ökade risk. Då flera vindkraftetableringar i regionen uppvisar godaproduktionsresultat (med Tavelberget som gott exempel) visar det att regionen ärintressant för introduktion och utvärdering av ny teknologi.