1,249 research outputs found
Wave packet dynamics in a monolayer graphene
The dynamics of charge particles described by Gaussian wave packet in
monolayer graphene is studied analytically and numerically. We demonstrate that
the shape of wave packet at arbitrary time depends on correlation between the
initial electron amplitudes and on the
sublattices and correspondingly (i.e. pseudospin polarization). For the
transverse pseudospin polarization the motion of the center of wave packet
occurs in the direction perpendicular to the average momentum . Moreover, in this case the initial wave packet splits
into two parts moving with opposite velocities along . If the
initial direction of pseudospin coincides with average momentum the splitting
is absent and the center of wave packet is displaced at along the same
direction. The results of our calculations show that all types of motion
experience {\it zitterbewegung}. Besides, depending on initial polarization the
velocity of the packet center may have the constant component ,
where is the Fermi velocity and is a function of
the parameter ( is the initial width of wave packet). As a result,
the direction of the packet motion is determined not only by the orientation of
the average momentum, but mainly by the phase difference between the up- and
low- components of the wave functions. Similar peculiarities of the dynamics of
2D electron wave packet connected with initial spin polarization should take
place in the semiconductor quantum well under the influence of the Rashba
spin-orbit coupling.Comment: 7 pages, 8 figures, to be published in Phys. Rev.
Psychological and pedagogical technologies for the correction of social fears of participants in a subculture of role-playing games of live action
Purpose of the study is to identify markers, "risk zones" that contribute to deviations among representatives of the subculture "roleviks", to elaborate a technology to correct negative experiences among "role" movement representatives to increase the efficiency of their adaptation. The following research methods were used in this study: “Questionnaire of the hierarchical structure of actual personal fears” (ISAS) methodology to identify phobias; Personality Belief Questionnaire – PBQ to specify dysfunctional beliefs impeding adaptation (emotional well-being, constructive relationships with other people, etc.). The research results suggest that a systematic integrated approach is a necessary condition for the success of the psychological technology aimed at overcoming negative experiences and maladaptation of "role" movement subculture representatives. A combination of diagnostic and correctional models to overcome social fears, deprivation and maladaptation makes up the essence of the technology. The research provides findings that can be used by managers of various levels in the education system, social workers, teachers and practical psychologists in the education system; they can also be of use while organizing special programs for educators, social and psychological services. It has been worked out to help students - “roleviks” to overcome their social fears. It represents a system of single interrelated activities determined to form and develop personal adaptive resources. It has been established that positive changes in adaptation strategies, a decrease in the level of social fears and anxiety are the main criteria for evaluating the effectiveness of the presented psychological-pedagogical technology. It is shown that the applied technology promotes the decrease of experienced fears intensity, forms stress resistance, and contributes to the selection of effective social interaction strategies.The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University
A new role of cooperation under economic sanctions as seen by residents of the Kaliningrad region
The current economic crisis conditions call for a search for new mechanisms to maintain the population's well-being. Within this setting, cooperation may be considered a priority form of entrepreneurial activity, enabling the consolidation of financial resources and reducing business costs. This article aims to assess the potential of consumer cooperation in the Kaliningrad region under anti-Russian sanctions. The authors analyse the features of cooperation development within the territory and investigate the demands and expectations of the local populace. The principal method employed in the study is a survey of residents of the Kaliningrad region (N = 481), with its results strongly indicating that conditions for a renaissance of cooperative economic models have emerged in the Russian exclave. The region's residents tend to express positive attitudes towards cooperation, drawing a link between economically challenging conditions and opportunities for cooperative development. Moreover, amongst respondents with personal or vicarious experience of cooperation, a substantially higher proportion assess cooperative practices positively. Yet, the deficit of interpersonal trust places a serious limitation on the development of cooperation. It is concluded that the economic crisis has shifted the focus of the region's population's expectations from social interests (collaborations with like-minded individuals) to undertakings aimed at increasing material well-being. Therefore, expectations of participating in cooperative activities are primarily associated with the opportunity to start one's own business and increase personal income
Wave packet dynamics in hole Luttinger systems
For hole systems with an effective spin 3/2 we analyzed analytically and
numerically the evolution of wave packets with the different initial
polarizations. The dynamics of such systems is determined by the
Luttinger Hamiltonian. We work in the space of arbitrary superposition of
light- and heavy-hole states of the "one-particle system". For 2D packets we
obtained the analytical solution for the components of wave function and
analyzed the space-time dependence of probability densities as well as angular
momentum densities. Depending on the value of the parameter ( is
the average momentum vector and is the packet width) two scenarios of
evolution are realized. For the initial wave packet splits into two
parts and the coordinates of packet center experience the transient
oscillations or {\it Zitterbewegung} (ZB) as for other two-band systems. In the
case when remains
almost cylindrically symmetric and the ripples arise at the circumference of
wave packet. The ZB in this case is absent. We evaluated and visualized for
different values of parameter the space-time dependence of angular momentum
densities, which have the multipole structure. It was shown that the average
momentum components can precess in the absence of external or effective
magnetic fields due to the interference of the light- and heavy hole states.
For localized initial states this precession has a transient character.Comment: 9 pages, 8 gigur
The organization of the rating system for assessing the quality of university students training
In spite the universities use the rating system of assessing for a quite long time, this issue is still not fully considered. The article is based on the position of insufficient state of knowledge of the multifunctionality of the students rating. The rating helps to reveal the potential of students. It is mentioned that the rating system of assessment is a tool that will improve the quality of training and provide the required level of motivation.
During the research, the following methods were used: analysis, synthesis, induction, deduction. As a result, the principles of the rating assessment system were revealed, a definition of the term "Rating" was given, its goals were indicated. As an example of the organization of the rating system of assessment, the Nyzhnii Novhorod State Pedagogical University and its "Regulations on the rating system for assessing the quality of student training" were used. It is noted that the rating includes: current check, midterm and final examinations. Further, all possible conditions under which the student receives points were identified and considered.
On the example of the NSPU named after Kozma Minin transferring of the rating points into a five-point grading rating system is presented. Also, the types of violations for which points are discarded, are considered. As the study showed, comprehensive planned system yields productive results for students and the university.peer-reviewe
Повседневность в рассказах Бориса Екимова
Boris Ekimov’s stories of the 2000s which formed the collection “Saturday of Souls” are analyzed
in the present article. The writer doesn’t set the purpose to recreate peasants’ Atlantis but perceives
today of the village as a reality in which a person lives.
The concepts of “daily life” and “daily occurrence” are differentiated in the article as the ones that
have different extension and occur at different times. Daily life is classified as sacral, it is one of
the manifestations of existence, while daily occurrence assumes an appeal to the private life of an
ordinary person in the present and his/her inclusiveness into the civilized everyday life.
The study of the everyday life of B. Ekimov’s characters that allowed him to describe the current state
of the village, which is characterized by the daily life coordinates reduction, has become the purpose
of this article. The deformed connections between people in the literary world of the writer are, first
of all, demonstrated in the transformation of the image of the master and changes in the character of
the neighborhood relationsВ настоящей статье анализируются рассказы Бориса Екимова 2000-х годов, составивших
сборник «Родительская суббота». Писатель не ставит целью воссоздать крестьянскую Атлантиду, а воспринимает сегодняшний день деревни как данность, в которой живет человек.
В статье разграничиваются понятия «быт» и «повседневность» как разнообъемные и разновременные. Быт отнесен к сакральному, это одно из проявлений бытия, повседневность же
предполагает обращение к приватной жизни обычного человека в настоящем, его включенность в цивилизационный обиход.
Целью статьи стало исследование повседневной жизни героев Б. Екимова, позволяющей ему
описать современное состояние деревни, характеризующееся редуцированностью бытийных координат. В художественном мире писателя деформированные связи между людьми проявляются, в первую очередь, в трансформации образа хозяина и изменении характера соседских отношений
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