Vortex manipulation in a superconducting matrix with view on applications

We show how a single flux quantum can be effectively manipulated in a superconducting film with a matrix of blind holes. Such a sample can serve as a basic memory element, where the position of the vortex in a [k x l] matrix of pinning sites defines the desired combination of n bits of information (2^n=k*l). Vortex placement is achieved by strategically applied current and the resulting position is read-out via generated voltage between metallic contacts on the sample. Such a device can also act as a controllable source of a nanoengineered local magnetic field for e.g. spintronics applications

AC Josephson properties of phase slip lines in wide tin films

Current steps in the current-voltage characteristics of wide superconducting Sn films exposed to a microwave irradiation were observed in the resistive state with phase slip lines. The behaviour of the magnitude of the steps on the applied irradiation power was found to be similar to that for the current steps in narrow superconducting channels with phase slip centers and, to some extent, for the Shapiro steps in Josephson junctions. This provides evidence for the Josephson properties of the phase slip lines in wide superconducting films and supports the assumption about similarity between the processes of phase slip in wide and narrow films.Comment: 7 pages, 2 figures, to be published in Supercond. Sci. Techno

I Smell Trouble: Using Multiple Scents To Convey Driving-Relevant Information

Cars provide drivers with task-related information (e.g. "Fill gas") mainly using visual and auditory stimuli. However, those stimuli may distract or overwhelm the driver, causing unnecessary stress. Here, we propose olfactory stimulation as a novel feedback modality to support the perception of visual notifications, reducing the visual demand of the driver. Based on previous research, we explore the application of the scents of lavender, peppermint, and lemon to convey three driving-relevant messages (i.e. "Slow down", "Short inter-vehicle distance", "Lane departure"). Our paper is the first to demonstrate the application of olfactory conditioning in the context of driving and to explore how multiple olfactory notifications change the driving behaviour. Our findings demonstrate that olfactory notifications are perceived as less distracting, more comfortable, and more helpful than visual notifications. Drivers also make less driving mistakes when exposed to olfactory notifications. We discuss how these findings inform the design of future in-car user interfaces

Личностный потенциал корпоративной культуры

Стаття присвячена розгляду взаємодії корпоративної культури і особистості в умовах організації. Аналіз здійснено на прикладі тиску корпоративної культури на особистість працівника. Схарактеризовано ключові елементи за моделлю Шейна: артефакти організації, проголошені в цілях і стратегіях цінності, базові положення в уявленнях про компанію, а також подано й інші характеристики моделі організаційної культури. Розкрито охоронну, інтегративну, регулятивну, адаптивну, орієнтаційну, мотиваційну, іміджеву функції, що привносить культура в організацію. Виділено й описано декілька типів тиску на особистість та її реакцій через партисипацію, тотальну уніфікацію і деіндивідуалізацію. Звернено увагу на дві категорії проблем стосовно тиску і деструкції індивідуальності людини – проблеми моралі та проблеми ефективності. Наголошено на важливості збереження людиною власної індивідуальності.The interaction of corporate culture and personality in organization is examined considering corporate culture puts pressure on the personality of an employee. The key elements of Schein’s model, (i.e. artifacts of organization, which are declared in companies’ aims and strategies, values) and other characteristics of organization culture are characterized. The guardian, integrative, regulating, adaptive, directional, motivational and image functions that culture brings to the organization are revealed. Some types of pressure on personality and the individual’s reactions, i.e. participation, absolute unification and deindividualization are distinguished and described. The author’s attention focuses on two categories of problems concerning the pressure on and destruction of a person’s individuality; these are morality issues and efficiency issues. The importance of saving a person’s individuality is stressed.В статье рассматривается взаимодействие корпоративной культуры и личности в условиях организации. Анализ проведен на примере давления корпоративной культуры на личность работника. Охарактеризованы ключевые элементы по модели Шейна: артефакты организации, провозглашенные в целях и стратегиях ценности, базовые положения в представлениях о компании, а также представлены и другие характеристики модели организационной культуры. Раскрыта охранная, интегративная, регулятивная, адаптивная, ориентационная, мотивационная, имиджевая функции, которые вносит культура в организацию. Выделены и описаны несколько типов давления на личность и ее реакций – партисипация, тотальная унификация и деиндивидуализация. Обращено внимание на две категории проблем относительно давления и деструкции индивидуальности человека – проблемы морали и проблемы эффективности. Подчеркнута важность сохранения человеком собственной индивидуальности

Observation of superluminal geometrical resonances in Bi2Sr2CaCu2O8+x intrinsic Josephson junctions

We study Fiske steps in small Bi2Sr2CaCu2O8+x mesa structures, containing only few stacked intrinsic Josephson junctions. Careful alignment of magnetic field prevents penetration of Abrikosov vortices and facilitates observation of a large variety of high quality geometrical resonances, including superluminal with velocities larger than the slowest velocity of electromagnetic waves. A small number of junctions limits the number of resonant modes and allows accurate identification of modes and velocities. It is shown that superluminal geometrical resonances can be excited by subluminal fluxon motion and that flux-flow itself becomes superluminal at high magnetic fields. We argue that observation of high-quality superluminal geometrical resonances is crucial for realization of the coherent flux-flow oscillator in the THz frequency range

Fiske Steps and Abrikosov Vortices in Josephson Tunnel Junctions

We present a theoretical and experimental study of the Fiske resonances in the current-voltage characteristics of "small" Josephson junctions with randomly distributed misaligned Abrikosov vortices. We obtained that in the presence of Abrikosov vortices the resonant interaction of electromagnetic waves, excited inside a junction, with the ac Josephson current manifests itself by Fiske steps in a current-voltage characteristics even in the absence of external magnetic field. We found that the voltage positions of the Fiske steps are determined by a junction size, but the Fiske step magnitudes depend both on the density of trapped Abrikosov vortices and on their misalignment parameter. We measured the magnetic field dependence of both the amplitude of the first Fiske step and the Josephson critical current of low-dissipative small $Nb$ based Josephson tunnel junctions with artificially introduced Abrikosov vortices. A strong decay of the Josephson critical current and a weak non-monotonic decrease of the first Fiske step amplitude on the Abrikosov vortex density were observed. The experimentally observed dependencies are well described by the developed theory.Comment: 21 pages, 7 figures, submitted to Physical Review

Анализ состояния вопроса утилизации низкопотенциальных энергетических ресурсов на объектах малой энергетики

Studying the issues of recovery of low-potential energy at smallscale energy facilities allowed to show the promising character of the organic Rankine cycle (ORC) technology as a technology for recovery or conversion of low-potential energy.The most promising developments in the field of the use and recovery of waste heat are described regarding application of ORC, which is widely used in geothermal sources, hot water boilers, gas turbine plants. Due to the constantly growing diversity of working fluids, ORC can be used within a wide temperature range from 100°C to over 350°C. Also, developments are underway in the design of ORC generators to increase reliability of its individual system units, such as turbines and expanders. Based on the above factors, it can be concluded that with a deeper study of the problems of adopting ORC technologies, they can become a very promising direction in development of heat power engineering.It has been determined that the main factor hindering the widespread adoption of the ORC technology is associated with high cost of heat exchange equipment due to increased heat exchange surfaces. It is shown that design of mini power plants and energy centres based on the use of low-potential energy requires improvement of mathematical modelling methods to reliably determine operating modes and characteristics of each of the units. Methods for modelling evaporation and condensation systems, including turbines and expanders using organic low-boiling working fluids, should be considered among the methods that are highly sought after. The methods for selecting a working fluid for ORC devices also have a significant impact on characteristics of the installation determining the range of cycle operating temperatures and pressures. The solution of the above problems can lead to a reduction in the cost of heat exchange equipment, and, consequently, to a decrease in costs for design of ORC generators. В статье рассмотрены вопросы утилизации низкопотенциальных энергетических ресурсов на объектах малой энергетики. Показана перспектива использования технологии органического цикла Ренкина (ОЦР) в качестве технологии утилизации или преобразования низкопотенциальной энергии.Приведены разработки в области реализации и утилизации бросового тепла. Наиболее перспективные из них представлены в применении ОЦР, который широко используется на геотермальных источниках, в водогрейных котельных, газотурбинных установках. За счёт постоянного растущего сортамента рабочих тел ОЦР может применяться в широком температурном диапазоне, начиная от 100°С и заканчивая свыше 350°С. Также ведутся разработки в области проектирования ОЦР-генераторов с целью повышения надёжности отдельных узлов системы, таких как турбины и детандеры. Исходя из вышеперечисленных факторов, можно сделать вывод, что при более глубоком исследовании проблем внедрения ОЦР-технологий они могут стать весьма перспективным направлением в развитии теплоэнергетики.Определено, что основным фактором, препятствующим широкому внедрению ОЦР-технологии, является высокая стоимость теплообменного оборудования из-за повышенных теплообменных поверхностей. Показано, что проектирование миниэлектростанций и энергокомплексов на основе использования низкопотенциальной энергии требует совершенствования методов математического моделирования для достоверного определения режимов работы и характеристик каждого из агрегатов. К востребованным следует отнести методы моделирования испарительных и конденсационных систем, в том числе турбин и детандеров, работающих на органических низкокипящих рабочих телах. Методики выбора рабочего тела для ОЦР-устройств также оказывают существенное влияние на характеристики установки, которые определяют диапазон эксплуатационных температур и давлений цикла. Решение вышеуказанных задач способно привести к удешевлению теплообменного оборудования, а, следовательно, снижению издержек на проектирование ОЦР-генераторов.

Laser Scanning Microscopy of HTS Films and Devices

The work describes the capabilities of Laser Scanning Microscopy (LSM) as a spatially resolved method of testing high_Tc materials and devices. The earlier results obtained by the authors are briefly reviewed. Some novel applications of the LSM are illustrated, including imaging the HTS responses in rf mode, probing the superconducting properties of HTS single crystals, development of twobeam laser scanning microscopy. The existence of the phase slip lines mechanism of resistivity in HTS materials is proven by LSM imaging.Comment: 17 pages, 21 figures, Submitted to Fizika Nizkikh Temperatur (Low Temperature Physics

CARoma Therapy: Pleasant Scents Promote Safer Driving, Better Mood, and Improved Well-Being in Angry Drivers

Driving is a task that is often affected by emotions. The effect of emotions on driving has been extensively studied. Anger is an emotion that dominates in such investigations. Despite the knowledge on strong links between scents and emotions, few studies have explored the effect of olfactory stimulation in a context of driving. Such an outcome provides HCI practitioners very little knowledge on how to design for emotions using olfactory stimulation in the car. We carried out three studies to select scents of different valence and arousal levels (i.e. rose, peppermint, and civet) and anger eliciting stimuli (i.e. affective pictures and on-road events). We used this knowledge to conduct the fourth user study investigating how the selected scents change the emotional state, well-being, and driving behaviour of drivers in an induced angry state. Our findings enable better decisions on what scents to choose when designing interactions for angry drivers

Fractional ac Josephson effect in unconventional superconductors

For certain orientations of Josephson junctions between two p_x-wave or two d-wave superconductors, the subgap Andreev bound states produce a 4pi-periodic relation between the Josephson current I and the phase difference phi: I ~ sin(phi/2). Consequently, the ac Josephson current has the fractional frequency eV/h, where V is the dc voltage. In the tunneling limit, the Josephson current is proportional to the first power (not square) of the electron tunneling amplitude. Thus, the Josephson current between unconventional superconductors is carried by single electrons, rather than by Cooper pairs. The fractional ac Josephson effect can be observed experimentally by measuring frequency spectrum of microwave radiation from the junction.Comment: 8 pages, 3 figures, RevTEX 4; v2. - minor typos corrected in proof