418 research outputs found
Graph kernel extensions and experiments with application to molecule classification, lead hopping and multiple targets
The discovery of drugs that can effectively treat disease and alleviate pain is one of the core challenges facing modern medicine. The tools and techniques of machine learning have perhaps the greatest potential to provide a fast and efficient route toward the fabrication of novel and effective drugs. In particular, modern structured kernel methods have been successfully applied to range of problem domains and have been recently adapted for graph structures making them directly applicable to pharmaceutical drug discovery. Specifically graph structures have a natural fit with molecular data, in that a graph consists of a set of nodes that represent atoms that are connected by bonds. In this thesis we use graph kernels that utilize three different graph representations: molecular, topological pharmacophore and reduced graphs. We introduce a set of novel graph kernels which are based on a measure of the number of finite walks within a graph. To calculate this measure we employ a dynamic programming framework which allows us to extend graph kernels so they can deal with non-tottering, softmatching and allows the inclusion of gaps. In addition we review several graph colouring methods and subsequently incorporate colour into our graph kernels models. These kernels are designed for molecule classification in general, although we show how they can be adapted to other areas in drug discovery. We conduct three sets of experiments and discuss how our augmented graph kernels are designed and adapted for these areas. First, we classify molecules based on their activity in comparison to a biological target. Second, we explore the related problem of lead hopping. Here one set of chemicals is used to predict another that is structurally dissimilar. We discuss the problems that arise due to the fact that some patterns are filtered from the dataset. By analyzing lead hopping we are able to go beyond the typical cross-validation approach and construct a dataset that more accurately reflect real-world tasks. Lastly, we explore methods of integrating information from multiple targets. We test our models as a multi-response problem and later introduce a new approach that employs Kernel Canonical Correlation Analysis (KCCA) to predict the best molecules for an unseen target. Overall, we show that graph kernels achieve good results in classification, lead hopping and multiple target experiments
Влияние модулированного питающего напряжения на межвитковую изоляцию
Описание научно-квалификационной работы. В работе исследованы особенности электротеплового старения изоляции низковольтных обмоток электрических двигателей в составе частотно-регулируемого привода и предложены рекомендации по повышению надежности.Description of scientific qualification work. The features of an electrothermal aging of electric motors low-voltage windings insulation in variable frequency drive are studied and recommendations on reliability improving are proposed in this work
Разработка мероприятий по повышению конкурентоспособности автоцентра
В процессе исследовалась конкурентоспособность ООО "Фольксваген Груп Рус" посредством выявления ключевых факторов конкурентоспособности и анализа конкурентоспособности автоцентров города Томска, а также посредством изучения открытых источников. В результате исследования был разработан комплекс мероприятия, который направлен на повышение конкурентоспособности автоцентра ООО "Фольксваген Груп Рус". Практическая значимость исследования состоит в возможности применения мер по повышению конкурентоспособности в исследуемом автоцентре. Актуальность работы обусловлена тем, что конкуренция на автомобильном рынке России с каждым годом усиливается и предприятие при использовании методов оценки конкурентоспособности, может осуществлять анализ своей деятельности на рынке.We research competitiveness of LLC Volkswagen Group Rus by means of identification of key factors of competitiveness and the analysis of competitiveness of autocenters of the city of Tomsk, and also by means of studying of open sources was investigated. As a result of probe the action complex which is directed to increase in competitiveness of autocenter of LLC Volkswagen Group Rus was developed. The practical importance of probe consists in a possibility of application of measures for increase in competitiveness at the studied autocenter. Relevance of work is caused by the fact that the competition in the automobile market of Russia amplifies also the enterprise when using methods of an assessment of competitiveness every year, can carry out the analysis of the activity in the market
Ремонт магистральных газопроводов ручной дуговой сваркой в условиях Крайнего Севера
Условным объектом исследования является магистральный газопровод из стали 13ХФА диаметром 1420 мм и толщиной стенки 25 мм. Целью работы является: разработка рекомендаций по выбору параметров режима и последовательности сварочных операций при ремонте магистральных газопроводов в условиях Крайнего Севера. В процессе исследования проводились расчет параметров режима сварки, прогнозирование химического состава и свойств сварного шва, определение расхода сварочных материалов, анализ вредных и опасных производственных факторов, расчёт экономической эффективности. В результате исследования был произведен подбор оборудования и электродов по полученным результатам, даны рекомендации по снижению вредных и опасных производственных факторов.The conditional object of the study is the main gas pipeline of steel 13HFA with a diameter of 1420 mm and a wall thickness of 25 mm. The purpose of the work is: development of recommendations on the choice of parameters of the regime and sequence of welding operations in the repair of main gas pipelines in the Far North. In the process of the study, the parameters of the welding regime were calculated, the chemical composition and properties of the welded joint were predicted, the consumables consumed, the analysis of harmful and dangerous production factors, and the calculation of economic efficiency. As a result of the research, the selection of equipment and electrodes was made based on the results obtained, recommendations were given to reduce harmful and dangerous production factors
Statistical analysis of industrial indicators of enterprises of various property forms
In this paper we study the impact of the economic crisis on the enterprises of subsection DM "Manufacture of transport means and equipment" manufacturing industries of Russia in the context of ownership. The study is based on comparative statistical analysis of available indicators of enterprises producing vehicles in 2013, 2014 and 2015 located in Russian, foreign and co-property
Основные факторы воздействия ферросплавного производства на атмосферу
На основных этапах технологического процесса получения ферросилиция образуются вредные выбросы, которыми являются колошниковые газы, шлаки и пыль. В открытых электропечах образуются газы, в которых содержится большое количество пыли и оксида углерода (до 80 % по объему). При этом оксид углерода смешивается с кислородом воздуха и сгорает с образованием диоксида углерода. В данной работе представлен количественный анализ пыле-газовых выбросов из открытой печи при получении ферросилиция и их содержание в атмосферном воздухе санитарно-защитной зоны предприятия «Юргинские ферросплавы».At the main stages of the technological process of obtaining ferrosilicon, harmful emissions are generated, which are blast-furnace gases, slags and dust. In open electric furnaces gases are formed, which contain a large amount of dust and carbon monoxide (up to 80% by volume). At the same time, carbon monoxide mixes with air oxygen and burns to form carbon dioxide. In this paper, a quantitative analysis of dust-gas emissions from an open furnace during the production of ferrosilicon and their content in the atmospheric air of the sanitary protection zone of the OAO Yurginsky Ferroalloys OJSC is presented
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