• Title/Summary/Keyword: Point interactions

Search Result 324, Processing Time 0.035 seconds

ALTERNATIVE PROOF OF EXISTENCE THEOREM FOR CERTAIN COMPETITION MODELS

  • Ahn, Inkyung
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.13 no.1
    • /
    • pp.119-130
    • /
    • 2000
  • We give alternative proof of the existence theorem for certain elliptic systems describing competing interactions with nonlinear di usion. The existence of positive solution depends on the sign of the principal eigenvalue of suitable operators of Schr$\ddot{o}$dinger type. If the sign of such operators are both positive, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

  • PDF

Chemical Shift and Quadrupolar Interactions in Solids

  • Kim Jin-Eun
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.10 no.1
    • /
    • pp.1-37
    • /
    • 2006
  • General expressions for solid state NMR lines are described for transitions under static, magic angle spinning, and variable angle spinning conditions in the case where the principal axis system for the anisotropic chemical shift tensor is noncoincident with that of the quadrupole coupling tensor. It is demonstrated that solid state NMR powder pattern simulation program VMAS based on the conventional grid point method of integrating over the Euler angle space is fast enough in comparison with the POWDER simulation package and Gauss-point method.

  • PDF

ELLIPTIC SYSTEMS INVOLVING COMPETING INTERACTIONS WITH NONLINEAR DIFFUSIONS II

  • Ahn, In-Kyung
    • Communications of the Korean Mathematical Society
    • /
    • v.12 no.4
    • /
    • pp.869-880
    • /
    • 1997
  • In this paper, we give sufficient conditions of certain elliptic systems involving competing iteractions with nonlinear diffusion rates. The existence of positive solution depends on the sign of the first eigenvalue of operators of Schr$\ddot{o}$dinger type. More precisely, if the sign of such operators are either both positive or both negative, then system has a positive solution. The main tool employed is the fixed point index of compact operator on positive cones.

  • PDF

Analysis of Approachs to Learning Based on Student-Student Verbal Interactions according to the Type of Inquiry Experiments Using Everyday Materials (실생활 소재 탐구 실험 형태에 따른 학생-학생 언어적 상호작용에서의 학습 접근 수준 분석)

  • Kim, Hye-Sim;Lee, Eun-Kyeong;Kang, Seong-Joo
    • Journal of The Korean Association For Science Education
    • /
    • v.26 no.1
    • /
    • pp.16-24
    • /
    • 2006
  • The purpose of this study was to compare student-student verbal interaction from two type's experiments; problem-solving and task-solving. For this study, five 3rd grade middle school students were selected and their verbal interactions recorded via voice and video; and later transcribed. The student-student verbal interactions were classified as questions, explanations, thoughts, or metacognition fields, which were separated into deep versus surface learning approaches. For the problem-solving experiment, findings revealed that the number of verbal interactions is more than doubled and in particular, the number of verbal interactions using deep-approach is more than quadrupled from the point of problem-recognition to problem-solution. As for the task-solving experiment, findings showed that verbal interactions remained evenly distributed throughout the entire experiment. Finally, it was also discovered that students relied upon a more deep learning approach during the problem-solving experiment than the task-solving experiment.

A Comparison of the Characteristics of Students' Verbal Interactions and Teachers' Help in Small Group Thinking Science Activities in Korea and in the U.K. (Thinking Science의 모둠별 활동에서 나타나는 한국과 영국 학생들의 논의와 교사들의 도움 특성 비교)

  • Choi, Byung-Soon;Shin, Ae-Kyung
    • Journal of Korean Elementary Science Education
    • /
    • v.25 no.4
    • /
    • pp.363-373
    • /
    • 2006
  • The purposes of this study were to analyze the within-group verbal interactions in Thinking Science activities and compare the characteristics of verbal interactions shown by the pupils as well as the differences in help by e teacher in Korea with those in the UK. For the purposes of this study, 16 pupils from comparable groups by cognitive level were selected from both countries. Verbal interactions and teacher help during group discussions were audio/ video taped and the types of students' interactions were classified into interactions related to problem solving, management of classroom loaming and others. The results of this study showed that the verbal interactions in Korean groups were more activated than those in the UK groups. However, the percentages of high level interactions such as metacognitive questions, elaborative suggestions and logical argumentations were higher in the UK groups than those in the Korean groups. Observation of the within-group activities revealed that the pupils of both countries shared some common ground in the following ways; neither recognized the need to formulate the hypothesis in the process of inquiry and that the procedures of discussion were dominated by the pupils of higher cognitive level as the discussion proceeded. It was also observed that the pupils in the UK were considerate in response to the questions posed by both their peers or the teacher, while the pupils in Korea were influenced by their prior knowledge in the subject. Analysis of the teacher help during the inquiry activities showed that the tendency fur the teacher to emphasize the process rather than the product in the procedures of discussion and the extent he/she allowed the pupils to think and consider were closely related to the characteristics of the teacher himself/herself and was found to be a point of commonality in both countries. However, the teachers in the UK revealed the tendency of trying to propose the task to the pupils in concrete and systematic ways and guide the discussion based on the thinking of the pupils, while those in Korea tried to use strategies designed to draw out active verbal interactions among the pupils.

  • PDF

Magnetic resonance study on boron substituted amorphous FeZrMn alloys

  • A.N.Ulyanov;Tian, Sheng-Bo;Kim, Kyeong-Sup;V.Srinivas;Yu, Seong-Cho
    • Proceedings of the Korean Magnestics Society Conference
    • /
    • 2003.06a
    • /
    • pp.90-91
    • /
    • 2003
  • Amorphous magnetic materials with competing magnetic interactions are the subject of current interest. Critical behaviour studies have been performed in order to understand the nature of the phase transition at the Curie point (T$\sub$c/) and type of magnetic ordering below the T$\sub$c/. In some cases there exists a temperature interval in which the magnetic system consists of ferromagnetic grains separated by the paramagnetic interlayers. Magnetic properties of nanoparticles embedded in amorphous matrix also are the subject of recent interest. While these materials exhibit excellent soft magnetic properties at room temperature, some of them have been found to be superparamagnetic in the temperature range above the T$\sub$c/ of the matrix. Thus the role of different magnetic phases in the intergrain magnetic coupling can possibly be taken apart in a sufficiently broad temperature range and investigated separately. In particular materials with competing magnetic exchange interactions show characteristics of enhanced magnetoresistance and softer magnetic properties when magnetic nanocrystals are dispersed in amorphous matrix. We expect careful magnetic measurements in the vicinity of T$\sub$c/ would throw some light on magnetic behaviour of above materials. We present here the FMR analysis of Fe$\sub$82/Mn$\sub$8-x/B$\sub$x/Zr$\sub$10/ alloy near the Curie point.

  • PDF

Reconstruction of Thermodynamics by the Concept of Available Energy (II) - Thermodynamics of Real World - (가용 에너지에 의한 열역학의 재구성 (II) - 실제세계 열역학 -)

  • Jung, Pyung-Suk
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.28 no.12
    • /
    • pp.1573-1581
    • /
    • 2004
  • Thermodynamic principles are described with a new point of view. In present study, the interaction between two systems is focused instead of the behavior of a system in conventional thermodynamics. The state change of a system cannot occur by itself but it is the result of the interaction between systems. However, the interaction itself is also the result of another kind of interaction, the interaction between two interactions. To reconstruct thermodynamics with such a point of view, the reversible world is imagined, in which conservations and measurements are discussed. There exists a conserved quantity for each mode of reversible interaction. The conserved transferring quantity in the interaction between interactions is the effective work, which is supposed to be measurable and conserved in reversible world. Effective work is the primary concepts of energy. It is the key factor to explain measurements, energy conservation and energy dissipation. The concepts developed in reversible world are applied to the real world in which irreversible phenomena may occur. Irreversibility is the result of effective energy dissipation, in which effective work irreversibly changes into entropy. A quantitative relation between the disappearing effective work and the generated entropy is dissipation equation which is given by experiments. A special temperature scale to give a very simple type of the dissipation equation is the absolute temperature scale, which gives the conventional conservation of energy.

Spatial Analysis to Capture Person Environment Interactions through Spatio-Temporally Extended Topology (시공간적으로 확장된 토폴로지를 이용한 개인 환경간 상호작용 파악 공간 분석)

  • Lee, Byoung-Jae
    • Journal of the Korean Geographical Society
    • /
    • v.47 no.3
    • /
    • pp.426-439
    • /
    • 2012
  • The goal of this study is to propose a new method to capture the qualitative person spatial behavior. Beyond tracking or indexing the change of the location of a person, the changes in the relationships between a person and its environment are considered as the main source for the formal model of this study. Specifically, this paper focuses on the movement behavior of a person near the boundary of a region. To capture the behavior of person near the boundary of regions, a new formal approach for integrating an object's scope of influence is described. Such an object, a spatio-temporally extended point (STEP), is considered here by addressing its scope of influence as potential events or interactions area in conjunction with its location. The formalism presented is based on a topological data model and introduces a 12-intersection model to represent the topological relations between a region and the STEP in 2-dimensional space. From the perspective of STEP concept, a prototype analysis results are provided by using GPS tracking data in real world.

  • PDF

The Relationship between Medical Students' Assessment of Standardized Patients and Patient‐Physician Interaction Score (표준화 환자에 대한 학생 평가와 환자의사관계 점수와의 관계)

  • Han, Eui-Ryoung;Kim, Sun;Chung, Eun-Kyung
    • Korean Medical Education Review
    • /
    • v.21 no.3
    • /
    • pp.150-154
    • /
    • 2019
  • When standardized patients (SPs) are used for educational purposes, the authenticity of role play and the quality of feedback are essential requirements of SPs. This study was conducted to investigate medical students' assessment of SPs and to identify the components of SPs' performance that were most strongly correlated with patient-physician interaction score. One hundred and forty-two fourth-year medical students were asked to complete the Maastricht Assessment of Simulated Patients (MaSP) at the end of a clinical performance examination. SPs evaluated the patient-physician interactions using a 4-point Likert scale (1=poor to 4=excellent). Medical students' assessment of SPs using the MaSP was positively correlated with patient-physician interactions (r=0.325, p<0.01). Items addressing the authenticity of role play (e.g., "SPs appear authentic," "SPs might be real patients," and "SPs answer questions in a natural manner") were closely correlated with patient-physician interactions (p<0.001, p=0.027, and p=0.017, respectively). These results showed that the MaSP appears to be a useful instrument for evaluating SPs' performance and that the authenticity of SPs' performance was positively correlated with medical students' interactions. In order to improve patient-physician interactions, medical students should be given opportunities to practice their skills with SPs who have been trained to portray patients with a specific condition in a realistic way.

Interactive Technology: Soft Engineering

  • Yoon, Joong-Sun
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.2682-2686
    • /
    • 2003
  • Recent paradigm in technology shifts from object-based technology to environment-based technology. Issue here is interaction among human, machines, and environment. This requires new interpretations for the space among them. Holistic interactions based on “Mom (embodiment)” suggest a good starting point for this endeavor. The past, present, future of technology are presented in terms of technology’s fundamental virtue: “humanizing technology” or “technology serving human.” Interactive technology initiative (ITI) is an interdisciplinary research group to search for the proper technology and the proper way of implementing technology: “interactive technology” or “soft engineering.” Some experimental activities conducted by ITI are presented in this organized session, “Interactive Technology.” Metatechnology, soft engineering, “Mom (embodiment),” holistic interactions, tangible space, and ubiquitous computing are key concepts in interactive technology.

  • PDF