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Unmanned Air Vehicles (UAVs) have recently gained attention due to their increased ability to perform sophisticated missions with less cost and/or risk than their manned counterparts. This thesis develops approaches to the use of compliant mechanisms in the design of deployable wings for small UAVs. Although deployable wings with rigid-link mechanisms have been used in the past to maintain flight endurance while minimizing required storage volume, compliant mechanisms offer many advantages in manufacturability and potential space savings due to function sharing of components. A number of compliant, deployable wing concepts are generated and a classification system for them is formed. The pool of generated concepts serves as a basis for stimulating future concept ideas. A methodology is also proposed for evaluating concepts for a given application. The approach to developing compliant designs for certain applications is illustrated through two example designs, which demonstrate key portions of the proposed design process. Each is modeled and analyzed to demonstrate viability.

This dissertation presents a substantial contribution to a new field of material science, the investigation of the magnetic properties of 3D curved surfaces, achieved by using a self-assembled geometrical transformation of an initially planar membrane. Essential magnetic properties of thin films can be modified by the process of transforming them from a 2D planar film to a 3D curved surface. By investigating and controlling the reasons that influence the properties, it is possible to improve the functionality of existing devices in addition to laying the foundation for the future development of microelectronic devices based on curved magnetic structures. To accomplish this, it is necessary both to fabricate high-quality 3D curved objects and to establish reliable characterization methods based on commonly available technology. The primary objective of this dissertation is to develop techniques for characterizing the static and dynamic magnetic properties of self-assembled rolled 3D geometries. The second objective is to examine the origin of shape-, size- and strain/curvature-induced effects. The developed approach based on anisotropic magnetoresistance (AMR) measurement can quantitatively define the rolling-induced static magnetic changes, namely the induced magnetoelastic anisotropy, thus eliminating the need for microscopic imaging to characterize the structures. The interpretation of the AMR signal obtained on curved stripes is enabled by simultaneous visualization of the domain patterns and micromagnetic simulations. The developed approach is used to examine the effect of sign and magnitude of curvature on the induced anisotropies by altering the rolling direction and diameter of the 'Swiss-roll'. Furthermore, a time-averaged imaging technique based on conventional microscopies (magnetic force microscopy and Kerr microscopy) offers a novel strategy for investigating nanoscale periodic domain wall oscillations and hence dynamic magnetic characteristics of flat and curved structures. This method exploits the benefit of a position-dependent dwell time of periodically oscillating DWs and can determine the trajectory and amplitude of DW oscillation with sub-100 nm resolution. The uniqueness of this technique resides in the ease of the imaging procedure, unlike other DW dynamics imaging methods. The combined understanding of rolling-induced anisotropy and imaging DW oscillation is utilized to examine the dependence of DW dynamics on external stimuli and the structure's physical properties, such as lateral size, film thickness, and curvature-induced anisotropy. The presented methods and fundamental studies help to comprehend the rapidly expanding field of 3-dimensional nanomagnetism and advance high-performance magneto-electronic devices based on self-assembly rolling.

The aim of the master's thesis is to develop theoretical and practical methods for increasing the efficiency of the enterprise’s vehicles and ensuring the development of the quality of operation of the operational service. The practical significance of the work lies in the application of methods and calculations to improve the efficiency of the operational and maintenance services of the enterprise LLC “Jasmine”. The introduction of the results of work at the enterprise will increase the efficiency of the use of rolling stock due to its rational use, as well as reduce material costs for transportation. In the master's thesis, an analysis was made of the activity of the enterprise, the possibility of using a tractor- transport unit in the construction of roads was considered, the construction of a transport bogies for semi trailers was proposed, and the maneuverability indicators of a motor train were determined. / Целью магистерской диссертации является разработка теоретических и практических методов повышения эффективности работы транспортных средств предприятия и обеспечение развития качества работы эксплуатационной службы. Практическое значение работы заключается в применении методик и расчетов для повышения эффективности работы эксплуатационной и обслуживающей службы предприятия ООО «Жасмин». Внедрение результатов работы на предприятии позволит повысить эффективность использования подвижного состава за счет рационального его использования, а также снизить материальные затраты на транспортные работы. В магистерской диссертации проведен анализ деятельности предприятия, рассмотрена возможность применения тракторно-транспортного агрегата при строительстве автомобильных дорог, предложена конструкция подкатной тележки для полуприцепа, а также определены показатели маневренности автотракторного поезда.

В работе приведены основные свойства и виды плоских полуфабрикатов из алюминия и алюминиевых сплавов. Рассмотрена технология производства плоских полуфабрикатов, технология и оборудование для проведения правки растяжением. Приведены новые патентные разработки в области прокатки плоских полуфабрикатов из алюминиевых сплавов. Представлены результаты исследования неравномерности деформации в процессе правки растяжением листового проката из алюминиевых сплавов. Приведено решение задачи правки растяжением полос из алюминиевых сплавов методом конечных элементов в программном комплексе ABAQUS с целью определения уровня деформаций. Выполнен анализ распределения деформаций при правке растяжением горячекатаных полос из алюминиевых сплавов. Неодинаковые значения деформаций по координатным направлениям объяснены с позиций анизотропии свойств прокатанных полос. / The paper presents the main properties and types of flat semi-finished products made of aluminum and aluminum alloys. The technology of production of flat semi-finished products, technology and equipment for straightening by stretching are considered. New patent developments in the field of rolling flat semi-finished products from aluminum alloys are presented. The paper presents the results of a study of the non-uniformity of deformation in the process of tensile straightening of sheet metal made of aluminum alloys. The solution of the problem of tensile straightening of strips of aluminum alloys by the finite element method in the ABAQUS software package is presented in order to determine the level of deformations. The analysis of the strain distribution during tensile straightening of hot-rolled strips of aluminum alloys is carried out. Unequal values of deformations along coordinate directions are explained from the standpoint of anisotropy of properties of rolled strips.

В работе рассматривается технология, включающая дуговую наплавку в инертном газе порошковой проволокой типа 50Х18 с последующей деформационной обкаткой. Разработан инструмент позволяющий реализовать деформационную обкатку шаром с регулируемой нагрузкой. Наплавленный слой имеет структуру метастабильного аустенита, который при нагружении преобразуется в твердый мартенсит. Измерения показывают, что технология приводит к увеличению твердости поверхности образца с 40 HRC до 54 HRC и снижению шероховатости с Ra 1,2 до Ra 0,4. Результаты позволяют рекомендовать технологию применительно к штокам и плунжерам гидроцилиндров. Магистерская диссертация включает в себя 71 страницу, 33 рисунка, 13 таблиц, 10 литературных источников. / The study shows a technology comprising MIG deposition of cored wire like 50Cr18 with the subsequent surface deformation. Specially developed device realizes adjustable ball rolling load. The structure of the weld includes a large share of metastable austenite, which transforms to hard martensite at loading. The measuring shows that the technology provides an increase of the sample’s surface hardness from 40 HRC to 54 HRC and decrease it’s roughness from Ra 1,2 to Ra 0,4. The results allow using the technology applying to hydraulic pistons. The master's thesis includes 71 pages, 33 figures, 13 tables, 10 literary sources.

No description available.

Объектом исследования являлось изучение микроструктуры и механических свойств трубных сталей 32Г2ФА, 38Г2Ф И 42Г2ФТ после горячей прокатки и термической обработки по различным режимам. На основе литературных данных и результатов собственных экспериментов в работе проведен анализ полученных механических свойств после различных обработок исследуемых сталей. Изучено влияние микролегирования на рост аустенитного зерна при нагреве сталей 32Г2ФА, 38Г2Ф И 42Г2ФТ до различных температур аустенитизации методами оптической микроскопии и растровой электронной микроскопии. / The object of the study was the study of the microstructure and mechanical properties of 32G2FA, 38G2F, and 42G2FT pipe steels after hot rolling and heat treatment in various modes. On the base of the literature and experimental data obtained mechanical properties of the studied steels after various treatments were analyzed. The effect of microalloying on the growth of austenite grains during heating of 32G2FA, 38G2F, and 42G2FT steels to various austenitization temperatures was studied by optical microscopy and scanning electron microscopy.

Объектом исследования являлось изучение микроструктуры и механических свойств сталей типа 32Г2ФА. На основе литературных данных и дюрометрических испытаний проведен анализ значений параметра отпуска и определен коэффициент С. Исследована микроструктура сталей после различных режимов отпуска методами электронной и оптической микроскопии. / The object of the study was the study of the microstructure and mechanical properties of steels of the 32G2FA type. On the basis of literature data and durometric tests, an analysis of the values of the tempering parameter was carried out and the coefficient C was determined. The microstructure of steels after various tempering regimes has been studied by electron and optical microscopy.

Syfte: Syftet med denna studie är att med hjälp av multivariata parametrar undersöka skillnader i fysisk extern belastning under den mest intensiva perioden (MIP) av match för spelare på ungdomselit och seniornivå samt att identifiera eventuella skillnader mellan positioner och halvlekar.Metod: En kvantitativ retrospektiv studie tillämpades, där spelare från ett seniorlag (SEN)spelandes i högsta divisionen i Sverige samt fotbollsspelare från ett ungdomselitlag (U19)från samma klubb spelades i näst högsta divisionen för åldersgruppen deltog i studien. Fysisk extern belastning mättes med hjälp av Global Positioning System (GPS). MIP analyserades utifrån spelares taktiska utgångsposition och med hjälp av multivariata parametrar. Rullande medelvärden användes för analys av 1-min MIP.Resultat: SEN täckte signifikant längre distans under den mest intensiva 1-mintusperioden av match jämfört med U19 (SEN 140 ± 22,3 m; U19 120 ± 24,1 m, p < 0.001). Vid jämförelse mellan positioner täcker SEN-Lateral längre distanser än U19-Lateral under mest intensiva 1-mintusperioden av MIP-kinematik (135 ± 23.5 m vs 104 ± 40.3 m, p = 0.015).Slutsats: Sammanfattningsvis konfirmerar denna studie en skillnad av den mest intensiva 1-minuters perioden för senior- och ungdomsspelare för MIPk. Studien visar att seniorspelare positionerade lateral på planen täcker längre distanser under MIPk jämfört med U19 på samma position. Praktiker bör beakta dessa skillnader i sina träningsupplägg för att kunna förbereda ungdomsspelare för de fysiska krav som ses i seniormiljön / Aim: The present study aimed to investigate differences in physical external load during the most intense period (MIP) of match play for youth and senior player and to indentify possible differences between positions and halves, with multivariate parameters. Method: A quantitative retrospective study was applied, players from a senior team playing in the highest division in Sweden participated in the study as well as football players from a youth elite team from the same club playing in the second highest division for the age group. Physical external load was measured using Global Positioning System (GPS). MIP was analyzed based on players' initial tactical position and using multivariate parameters. Rolling averages were used to analyze 1-min MIP.Results: SEN covered significantly longer distances during the most intense 1-min period of the match compared to U19 (SEN 140 ± 22,3 m; U19 120 ± 24,1 m, p < 0.001). When comparing between positions, SEN-Lateral covers longer distances than U19-Lateral during the most intense 1-minute period of the MIPk (135 ± 23.5 m vs 104 ± 40.3 m, p = 0.015).Conclusions: In conclusion, this study confirms a difference in the most intense 1-minute period for senior and youth players for MIPk. The study shows that senior players positioned laterally on the pitch cover longer distances during MIPk compared to U19-Lateral. Practitioners should consider these differences in their training programmes in order to prepare youth players for the physical demands seen in the senior environment.