Mapping bedfast and floating thermokarst lake ice and determining lake depth using Sentinel 1 Synthetic Aperture Radar Remote Sensing on the west shore of Hudson Bay, Canada and Prudhoe Bay, Alaska

Thermokarst lakes are an abundant feature in Arctic permafrost regions and cover up to 40 percent of the land area. During winter shallow lakes freeze to the bed (bedfast ice) while lakes which are deeper than the maximum ice thickness up to 2 m preserve perennial liquid water below the ice (floating ice). The different lake ice regimes have an impact on the energy distribution to the surrounding permafrost, available aquatic habitat and geomorphological processes. Completely frozen lakes contribute less energy and gas fluxes to the landscape and atmosphere while floating ice conditions support the development of a talik, a continuously unfrozen layer, as the remaining liquid water provides energy to the surrounding permafrost. This has an impact on permafrost thawing and geomorphological development as taliks can favour subsurface lake drainage, permafrost degradation and lateral lake erosion. Bedfast or floating ice conditions are dependant on the maximum ice thickness. Ice growth is determined by winter temperatures and snow conditions as a thicker snow cover provides insulation and reduce ice growth. In this study Sentinel 1 synthetic aperture radar (SAR) data for four winters from 2015 to 2018 was used to investigate thermokarst lakes and compare lake ice regimes in two study areas with permafrost conditions. One is in the area of Prudhoe Bay, North Slope Borough, Alaska and the other on the west shore of Hudson Bay near Churchill, Manitoba, Canada. Synthetic aperture radar remote sensing allows to distinguish between bedfast and floating ice due to different backscatter intensities. While bedfast ice absorbs the radar signal and appears dark on the radar image, floating ice shows a strong reflectance and appears bright. This is due to differences in the dielectric contrast between ice and sediment (lake bed) and ice and liquid water, respectively. Additionally the maximum ice thickness was approximated by calculating ice growth based on freezing degree days from MODIS land surface temperature data. With the resulting ice growth curve the maximum water depth of lakes which freeze completely to the ground was determined through the date when they became bedfast. Bedfast lake ice percentages decreased over the study period in Prudhoe Bay while they varied widely in Churchill. The average proportions were similar for both study areas with 68 % in Prudhoe Bay and 62 % in Churchill. The lakes in Prudhoe Bay showed a trend towards floating ice regimes which was not detectable in Churchill. Relationships between winter temperatures and the amount of bedfast ice were not linear and indicate the presence of tipping points. Maximum ice thickness was estimated to be 160 cm in Prudhoe Bay which seems valid, while the similar ice thickness in Churchill is most likely overestimated by the used method. Future work in permafrost regions and the establishment of long term observations should help to understand trends more reliable and detect relationships between climate and resulting landscape response

AN EXAMINATION OF LANGUAGE REQUIREMENTS FOR NEWLY-GRADUATED STUDENTS BY QUANTITATIVE RESEARCH

Nowadays the rising unemployment rate for newly-graduated students poses a considerable problem. Although obtaining a degree and certificate are not enough on the labour market, it is a fact that college graduates' unemployment rates over all are still lower than the national average. These days the successful graduate job applicant has to (fluently) speak foreign language(s). In order to ensure that candidates can fulfil this requirement, universities and colleges have to modify the language teaching strategy according to the needs of the labour market

Examination of Language Requirements for Newly-graduated Students by Quantitative Research

Nowadays the rising unemployment rate for newly-graduated students poses a considerable problem. Although obtaining a degree and certificate are not enough on the labour market, it is a fact that college graduates' unemployment rates over all are still lower than the national average. These days the successful graduate job applicant has to (fluently) speak foreign language(s). In order to ensure that candidates can fulfil this requirement, universities and colleges have to modify the language teaching strategy according to the needs of the labour market

AN EXAMINATION OF LANGUAGE REQUIREMENTS FOR NEWLY-GRADUATED STUDENTS BY QUANTITATIVE RESEARCH

Nowadays the rising unemployment rate for newly-graduated students poses a considerable problem. Although obtaining a degree and certificate are not enough on the labour market, it is a fact that college graduates' unemployment rates over all are still lower than the national average. These days the successful graduate job applicant has to (fluently) speak foreign language(s). In order to ensure that candidates can fulfil this requirement, universities and colleges have to modify the language teaching strategy according to the needs of the labour market

Проблемы обеспечения пожарной безопасности в образовательных учреждениях

В статье рассматриваются актуальные вопросы и мероприятия по обеспечению пожарной безопасности в образовательных учреждениях.In article topical issues and actions for ensuring fire safety in educational institutions are considered

Разработка плана локализации и ликвидации аварий на автозаправочной станции Юргинского ЛПУМГ ООО «Газпром трансгаз Томск»

Целью выпускной квалификационной работы является: разработка порядка действий производственного персонала Юргинского ЛПУМГ в случае аварии на опасном производственном объекте по сценарию аварии "Пожар пролива нефтепродуктов и взрыв топливно-воздушной смеси". В работе произведен анализ нормативных документов в области обеспечения пожарной безопасности, разработан порядок действий производственного персонала (руководителей и работников), расчет аварии по сценарию пожар пролива, произведены расчеты для выполнения мероприятий по локализации и ликвидации возможной ЧС.The purpose of the final qualification work is: development of a procedure for the production personnel of the Yurginsky LPUMG in the event of an accident at a hazardous production facility according to the accident scenario "A fire of the spill of oil products and an explosion of a fuel-air mixture." The paper analyzes regulatory documents in the field of ensuring fire safety, developed a procedure for actions of production personnel (managers and workers), calculation of an accident according to the scenario of a strait fire, calculations were made to carry out measures to localize and eliminate a possible emergency

Асинхронный электропривод насоса прямой подачи подкачивающей насосной станции

Цель работы - разработка частотно регулируемого электропривода насоса прямой подачи подкачивающей насосной станции в соответствии с требованиями технического задания и исследование его работы методом моделирования на ЭВМ. В выпускной квалификационной работе был произведён расчет и выбор приводного двигателя; преобразователя частоты, а также определенны параметры силовой цепи. Обоснован выбор способа управления, рассчитаны механические и электромеханические характеристики. Методом имитационного моделирования на ЭВМ исследованы переходные процессы в основных режимах работы.The work purpose - development of frequency adjustable electric drive of the pump of direct giving of the pumping-up pump station according to requirements of the requirement specification and a research of its work as a model operation method on the COMPUTER. In final qualification work calculation and the choice of the drive engine was made; a frequency transformer and also parameters of a power chain are certain. The choice of a way of management is reasonable, mechanical and electromechanical characteristics are calculated. The method of a simulation modeling on the COMPUTER investigated transition phenomenons in the main duties