383 research outputs found
Rigidity of lattice domes
The means of ensuring total rigidity of lattice domes, using comparison with solid shells of 1-3 layers are discussed. Irregularities of manufacture, processing, and other factors are considered, as they relate to diminution of rigidity. The discussion uses the concepts of upper and lower critical loads on the structure in question
Spherical Bondi accretion onto a magnetic dipole
Quasi-spherical supersonic (Bondi-type) accretion to a star with a dipole
magnetic field is investigated using resistive magnetohydrodynamic simulations.
A systematic study is made of accretion to a non-rotating star, while sample
results for a rotating star are also presented. A new stationary subsonic
accretion flow is found with a steady rate of accretion to the magnetized star
smaller than the Bondi accretion rate. Dependences of the accretion rate and
the flow pattern on the magnetic momentum of the star and the magnetic
diffusivity are presented. For slow star's rotation the accretion flow is
similar to that in non-rotating case, but in the case of fast rotation the
structure of the subsonic accretion flow is fundamentally different and
includes a region of ``propeller'' outflow. The methods and results described
here are of general interest and can be applied to systems where matter
accretes with low angular momentum.Comment: 15 pages, 15 figures, used emulapj.st
Predicting the breaking onset of surface water waves
Why do ocean waves break? Understanding this important and obvious property of the ocean surface has been elusive for decades. This paper investigates causes which lead deep-water two-dimensional initially monochromatic waves to break. Individual wave steepness is found to be the single parameter which determines whether the wave will break immediately, never break or take a finite number of wave lengths to break. The breaking will occur once the wave reaches the Stokes limiting steepness. The breaking probability and the location of breaking onset can be predicted, properties of incipient breakers measured. Potential applications to field conditions are discussed
THE PNEUMATIC TRAINING APPARATUSES WITH ADJUSTABLE ELASTICITY
Introduction
Powerful impact loads are present in many sports. Their
frequent repetition in athletic training causes overloading and injuries
to the motor support apparatus of many athletes. As a result, training
loads must be decreased, which disrupts training plans and creates a
number of complications. This refers particularly to jumping events. In
gymnastics, for example, over 50% of all injuries are related to jumping
exercises and the gymnast's landings
FACTORS OF SOCIAL AND PSYCHOLOGICAL ADAPTATION OF TEENAGERS TO EDUCATION IN SUVOROV MILITARY SCHOOL
The aim of the article is to reveal the content of the concept ofsocio-psychological adaptation.Methods. In the course of work theoretical methods of research are used: an overview and synthesis of approaches to the study of such a theoretical construct as adaptation and disadaptation; practical methods: methods of diagnostics of socio-psychological adaptation by K. Rogers and P. Diamond (SPA) and multi-factor personality questionnaire by R. Cattell (CPQ). The research is summative. Statistical processing is carried out using the computer programs STATISTICA 6.0 and MS Excel; the method of multiple regression analysis is used to highlight the personal factors influencing the level of adaptation of pupils of the Suvorov military school. Results. According to the empirical study, the authors describe the obtained factors of socio-psychological adaptation and disadaptation of adolescents enrolled in the course at Suvorov military school of the Ministry of Defense of the Russian Federation. The results of empirical research of features of adolescents’ adaptation to the conditions of a military educational institution are presented. Special attention is paid to the selection of personality traits characterizing the failure probability of disadaptation. The authors justified the need and described the possibility of organizing a psychological-pedagogical support of adolescents at the initial stage of studying in military educational institution of the closed type.Scientific novelty. The article proposes the authors’ approach to the concept of socio-psychological adaptation; the main indicators of successful socio-psychological adolescents’ adaptation to the conditions of Suvorov military school are identified; the indicators that predict the risk of the failure probability of disadaptation are given. It is concluded that the development of adaptive capacity should be achieved through personal components.Practical significance. The «targets» of the correctional developing influence at the stage of adaptation of teenagers to educational activity in the closed military school are allocated. Promising directions of change in emphasis in the content of psychological and pedagogical support of adolescents at the initial stage of study in Suvorov military school of the defense Ministry are noted. The materials and results of the study described in the article can be used while developing adaptation programmes of younger adolescents to training in pre-University educational institutions of the Ministry of Defense of the Russian Federation.Цель. Статья раскрывает авторский подход к понятию социально-психологической адаптации. Методология и методики исследования. В ходе работы были использованы теоретические методы исследования – обзорный анализ и синтез подходов к изучению таких конструктов, как адаптация и дезадаптация; практические методы – методики диагностики социально-психологической адаптации К. Роджерса и Р. Даймонда (ДПА) и многофакторный личностный опросник Р. Кеттела (CPQ). Исследование носило констатирующий характер. Статистическая обработка осуществлялась с использованием компьютерных программ STATISTICA 6.0 и MS Excel. Для выделения личностных факторов, влияющих на уровень адаптации воспитанников суворовского училища, применялся метод множественного регрессионного анализа. Результаты. Описаны полученные в ходе эмпирического исследования факторы социально-психологической адаптации и дезадаптации подростков, поступивших на первый курс обучения в суворовское военное училище (СВУ) Министерства обороны РФ (МО РФ). Продемонстрированы особенности адаптации курсантов к условиям военного учебного заведения. Особое внимание уделено личностным характеристикам воспитанников, повышающим вероятность возникновения дезадаптации. Обоснована необходимость и показаны возможности организации психолого-педагогического сопровождения подростков на начальном этапе обучения в учебном заведении закрытого типа. Научная новизна. Предложен авторский подход к понятию социально-психологической адаптации; выделены основные показатели успешности этого процесса в условиях СВУ и показатели, позволяющие прогнозировать риск возникновения дезадаптации, а следовательно, своевременно проводить профилактические мероприятия. Сделан вывод о том, что развитие адаптационных способностей подростков должно осуществляться через личностные компоненты. Практическая значимость. Выделены «мишени» коррекционно-развивающего воздействия на этапе адаптации подростков к образовательной деятельности в закрытом военно-учебном заведении. Обозначены перспективные направления изменения акцентов в содержании психолого-педагогического сопровождения подростков на начальном этапе обучения в училищах военного типа. Материалы статьи могут быть использованы при разработке программ адаптации младших учащихся довузовских образовательных организаций МО РФ.
Effect of exchange electron-electron interaction on conductivity of InGaAs single and double quantum wells in ballistic regime
We report an experimental study of quantum conductivity corrections for
two-dimensional electron gas in a GaAs/InGaAs/GaAs single and double quantum
wells in a wide temperature range (1.8-100) K. We perform a comparison of our
experimental data for the longitudinal conductivity at zero magnetic field to
the theory of interaction-induced corrections to th transport coefficients. In
the temperature range from 10 K up to (45-60) K, wich covers the ballistic
interaction regimes for our samples, a rather good agreement between the theory
and our experimental results has been found
Novel quantum NMR magnetometer non-contact defectoscopy and monitoring technique for the safe exploitation of gas pipelines
Pipeline transportation has already proved to be a high-performance tool of resources transportation for the efficient functioning of modern society. However, an aggressive environment, the modernization of existing pipelines and the building of new pipelines pose a number of problems to be solved for secure exploitation. Such problems include mapping, systems certification, technical inspection and monitoring. Recently much attention has being paid to the effective solution of these problems, with no interference into the functioning of the existing systems (non-contact methods), and the magnetometric technique is one such method. The method presented in this paper is based on the interpretation of the absolute value of the magnetic field of an object, which allows us to carry out measurements more accurately compared to other approaches. This paper presents the preliminary results of the usage of high-precision absolute quantum Overhauser “POS” (proton Overhauser sensor) magnetometers in the oil-and-gas field. The field work conducted in the summer of 2013 showed that this equipment has great potential for safe exploitation of oil-and-gas pipelines. The efficiency of the geophysical equipment for gas pipelines of a large diameter (1400 mm) was also confirmed under actual operating conditions. © 2014 WIT Press.International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen
ГРАВІТАЦІЙНИЙ ПОТЕНЦІАЛ ВНУТРІШНЬОРЕГІОНАЛЬНОЇ ТОРГІВЛІ ВАЛЮТНИХ АЛЬЯНСІВ
The paper develops the concept of regional monetary integration, the framework of which includes three alternative exchange rate arrangements: currency board, full or parallel dollarization and currency union. Each of them has its own peculiarities of formation and development, its own advantages and disadvantages, but the common feature is unconditional exchange rate unification. The concept of currency proto-integration was introduced, which foresees the exchange of information on monetary initiatives between monetary authorities, consideration of counterparties’ interests to minimize risks or maximize common benefits in the field of monetary relations.In order to assess the effectiveness of monetary integration for the development of intra-regional trade flows, we use gravity modeling based on a sample of more than 105 thousand observations of bilateral trade flows within monetary integrational and proto-integrational alliances. Gravity model includes the parameters of the volumes of bilateral trade, gross domestic product, weighted distances between states and the system of dummy-variables for the determination of monetary associations, common language and borders between trading states. The applied gravity model demonstrates a fairly high level of certainty for South America, Europe, South and East Asia (R2 for them was 0.71, 0.63 and 0.54, respectively). It was established that among the monetary alliances, the integrational and proto-integrational structures of South America, Asia and Europe were most effective in the aspect of intensifying intraregional trade. Between the African monetary blocks, the regular growth of mutual trade was observed only in the West African Economic and Monetary Union, while the rest was characterized by reverse dependence.Развивается концепция региональной валютной интеграции, к каркасу которой включены три режимы валютного курса: валютный совет, полную или параллельную долларизацию и валютный союз. С целью оценки эффективности валютной интеграции для развития внутрирегиональных торговых потоков использовано гравитационное моделирование. Модель продемонстрировала достаточно высокий уровень достоверности для Южной Америки, Европы, Южной и Восточной Азии. Установлено, что среди валютных объединений наиболее эффективными в аспекте интенсификации внутренней торговли оказались интеграционные и протоинтеграционные структуры Южной Америки, Азии и Европы. Среди африканских валютных союзов регулярный прирост взаимной торговли наблюдался только в Западно-Африканском экономическом и валютном союзе.Розвинуто концепцію регіональної валютної інтеграції, до каркасу якої включено три режими валютного курсу: валютну раду, повну або паралельну доларизацію та валютний союз. Для кожного із них характерні свої особливості розвитку, переваги і недоліки, однак їхньою спільною рисою є безумовна валютно-курсова уніфікація. Введено поняття валютної протоінтеграції, яка включає разом із практикою здійснення регулярних трансакцій з іноземною валютою та обміну інформації щодо монетарних ініціатив також урахування інтересів контрагентів для мінімізації ризиків чи максимізації спільних вигід у сфері валютних відносин.Проведено аналіз ефективності валютної інтеграції для розвитку внутрішньорегіональних торговельних потоків. Дослідження базувалось на використанні методології гравітаційного моделювання торгівлі на основі вибірки із понад 105 тис. спостережень білатеральних торговельних потоків у рамках інтеграційних і протоінтеграційних валютних об’єднань. Гравітаційне моделювання враховувало параметри обсягів білатеральної торгівлі, валового внутрішнього продукту, зваженої відстані між державами і системи фіктивних змінних для врахування впливів членства у валютних об’єднаннях, наявності спільної мови та кордонів між торгуючими державами. Результати гравітаційного моделювання продемонстрували доволі високий рівень статистичної достовірності для Південної Америки, Європи, Південної та Східної Азії (R2 для них становить 0,71; 0,63 та 0,54 відповідно). Установлено, що серед валютних об’єднань найбільш ефективними в аспекті інтенсифікації внутрішньої торгівлі виявились інтеграційні та протоінтеграційні структури Південної Америки, Азії та Європи. В Африці регулярний приріст взаємної торгівлі спостерігався лише в Західно-Африканському економічному і валютному союзі, решта союзів характеризуються зворотною залежністю
Psychological factors of online-learning efficiency of students
The spread of e-learning in high education stimulates investigation of psychological characteristics of successful students of online courses. The aim of our paper was to find psychological predictors of the effectiveness of online learning. The sample consisted of 215 students of the Ural Federal University. The personal sphere of students was studied with the help of personality questionnaire Big Five (R. McCrae and P. Costa); diagnosis of students' educational activity motives (T. O. Gordeeva, E. N. Osin, O. A. Sychev); diagnosis of the dominant perceptual modality (S. Efremtseva); scale of progressive matrices by J. Raven (diagnosis of the level of intelligence based on the evaluation of the effectiveness of non-verbal tasks). The results of the respondents expressed attitude to e-learning and their final scores of online courses have been processed with help of factual analysis. We have found that the main personal characteristics of successful online-students are their intrinsic and extrinsic motivation and level of intelligence, such personal qualities as goodwill and openness to new experience, moreover, the length of study at university and online courses is also important. The results show that one of the most difficult area of online courses is the evaluation of learning outcomes. The recognition of individual psychological characteristics of more and less successful MOOC-students are important information for creators and university teachers working in this format. This data gives understanding how to make the situation of e-learning success and realize the ideas of adaptive learning. © 2019 LLC Ecological Help. All rights reserved
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