• Title/Summary/Keyword: Self-Consistent Model

Search Result 138, Processing Time 0.026 seconds

New PDP cell designs for high luminous efficiency and radiation transport model in PDP

  • Yang, Sung-Soo;Shin, Seung-Won;Kim, Hyun-Chul;Lee, Jae-Koo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.590-593
    • /
    • 2002
  • Using two- and three-dimensional fluid simulation codes, we have suggested several new plasma display panel (PDP) cell structures that have high luminous efficiency compared with conventional structure. To improve the luminance and discharge efficiency, we utilize long discharge path, lower electric field region, and reduction of power consumption by adding one auxiliary electrode or reducing the electrode area. Consequently, luminous efficiency increases about 1.8 times. Furthermore for the resonance radiation trapping effect in PDP system, we have described a self-consistent radiation transport model coupled with fluid simulation using modified Holstein's equation.

  • PDF

Development of a Family Pattern Appraisal to Guide a Rogerian Nursing Practice (Rogers 이론에 근거한 가족양상 사정지침개발)

  • 이광옥;한영란;김희정
    • Journal of Korean Academy of Nursing
    • /
    • v.25 no.4
    • /
    • pp.751-773
    • /
    • 1995
  • We, clinical nurse specialists practising and guiding student practice in a Community health nursing clinic, wanted to develop a family pattern appraisal consistent with Rogers' conceptual system, the nursing model guiding our practice. We use Rogers' model because it is harmonious with the traditional Korean view of the one human, natural and cosmic world. The purpose of our research was to contribute to science - based nursing practice, not only, one helpful model, but also a model of how to use, in guiding practice, a conceptual system which reflects nurse practitioners' philosophy of nursing, is intellectually satisfying, and enriches meaning in daily nursing life. The research objectives were to review the literature on Rogers' model and analyse it according to Kim's five - level analytical framework, to explore Rogers' definition of family, to review appraisals based on Rogers' model, and to develop a family appraisal which is culturally appropriate for use in our community. This work including the use of the appraisal and its refinement with families in our practice which was done during 1994 and 1995, in Seoul, in the Capital of the Republic of Korea. At the highest level of analysis, Rogers conceptual system emphasizes acausality and multidimentional meaning ; the world view is characterized by process, movement and wholeness. The epistemology Is one of holism and the knowledge base includes all forms of experience, from sensory to mystical, objective, and subjective. At the metaparadigm level, nursing focuses on the unitary human being and the environment. At the level of nursing philosophy, the model identifies human being, nursing, nurse, and illness and health. At the paradigm level the model assumes the irriducibility of the human to parts, noncausality and continual change. Rogers' practice methodology consists of pattern manifestation appraisal and deliberative mutual patterning. Under-standing patterns and patterning of people is the key to helping them achieve their potential. At the theory level, the basic assumptions, key concepts, and homeodynamic principles were identified. Rogers states the family energy field is an undividable, four-dimensional negentropic energy field which is in a larger envircinmental field show-ing such characteristics as cannot be predicted by knowledge of individual family members. Based on the word of Rogers scholars, we chose Rogers' correlates of patterning to understand the family unit as a whole-frequency, rhythms, motion, time perception, sleeping-waking beyond waking, pragmatic -imaginative-visionary to develop the appraisal. We, also used some of Barrel's (1988) criteria including interpersonal network and professional health care access and use, and Cordon's (1982) criteria including self perception - self concept modified to fit the family. Our family Pattern appraisal included 1. Influencirg data, 2. Professional health care access and use, 3. Family self perception-self concept, 4. Family interpersonal network, 5. Sleep-wake-be-yond waking, 6. Pragmatic-imaginary-visionary, 7. Family frequency and rhythm, 8. Family motion, 9. Family time perception. The appraisal was used with four families and modified to eliminate overlap and to make it possible for the family member to express themselves more easily. We plan to gain more experience with the appraisal toward further development of the tool.

  • PDF

Simulation of Capacitively Coupled RF Plasma; Effect of Secondary Electron Emission - Formation of Electron Shock Wave

  • Park, Seung-Kyu;Kim, Heon-Chang
    • Journal of the Semiconductor & Display Technology
    • /
    • v.8 no.3
    • /
    • pp.31-37
    • /
    • 2009
  • This paper presents one and two dimensional simulation results with discontinuous features (shocks) of capacitively coupled rf plasmas. The model consists of the first two and three moments of the Boltzmann equation for the ion and electron fluids respectively, coupled to Poisson's equation for the self-consistent electric field. The local field and drift-diffusion approximations are not employed, and as a result the charged species conservation equations are hyperbolic in nature. Hyperbolic equations may develop discontinuous solutions even if their initial conditions are smooth. Indeed, in this work, secondary electron emission is shown to produce transient electron shock waves. These shocks form at the boundary between the cathodic sheath (CS) and the quasi-neutral (QN) bulk region. In the CS, the electrons emitted from the electrode are accelerated to supersonic velocities due to the large electric field. On the other hand, in the QN the electric field is not significant and electrons have small directed velocities. Therefore, at the transition between these regions, the electron fluid decelerates from a supersonic to a subsonic velocity in the direction of flow and a jump in the electron velocity develops. The presented numerical results are consistent with both experimental observations and kinetic simulations.

  • PDF

Relationship Between Self-Reflection, Critical Thinking Disposition, Muti Cultural Experience and Cultural Competence in nursing students (간호대학생의 자아성찰, 비판적 사고성향 및 다문화 경험과 문화적 역량과의 관계)

  • Pak, So-Young
    • Journal of Digital Convergence
    • /
    • v.14 no.12
    • /
    • pp.345-355
    • /
    • 2016
  • As Korea has been rapidly transformed to be a multi cultural society, it becomes essential for nursing provider to develop cultural competency. The purpose of this study was to identify impact of self-reflection, critical thinking disposition and multi cultural experience on nursing student's cultural competence. A convenience sample of 148 nursing students was obtained from a university in Gyeonggi Province. Data was analyzed using Pearson correlation and multiple regression. Significant relationships were found between self-reflection, critical thinking disposition, multi cultural experience and cultural competence in nursing student. The result of multiple regression indicates that critical thinking disposition (${\beta}=0.27$, p=.005), self-reflection (${\beta}=0.21$, p=.040) were the most consistent predictors of cultural competence and explained 26.0%. Thus, it is necessary to develop multi cultural education program including self-reflection and critical thinking disposition. The findings suggest the necessity to explore further various factors affecting the cultural competence and to conduct research for establishment a theoretical model.

Electron Mobility Model in Strained Si Inversion Layer (응력변형을 겪는 Si 반전층에서 전자 이동도 모델)

  • Park Il-Soo;Won Taeyoung
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.42 no.3 s.333
    • /
    • pp.9-16
    • /
    • 2005
  • The mobility in strained Si inversion layer on $Si_{1-x}Ge_x$ is calculated considering a quantum effect(subband energy and wavefunction) in inversion layer and relaxation time approximation. The quantum effect in inversion layer is obtained by using self-consistent calculation of $Schr\ddot{o}dinger$ and Poisson equations. For the relaxation time, intravalley and intervalley scatterings are considered. The result shows that the reason for the enhancement in mobility as Ge mole fraction increases is that the electron mobility in 2-폴드 valleys is about 3 times higher than that of 4-폴드 valleys and most electrons are located in 2-폴드 valleys as Ge mole fraction increases. Meanwhile, for the phonon-limited mobility the fitting to experimental data, Coulomb and surface roughness mobilities are included in total mobility, Deformation potentials are selected for the calculated effective field, temperature, and Ge mole fraction dependent mobilities to be fitted to experimental data, and then upgraded data can be obtained by considering nonparabolicity in Si band structure.

A Study on the Regional Self-sufficiency for In-patient Care Services (입원의료의 진료권별 자체충족도에 관한 연구)

  • Han, Dal-Sun;Kwon, Soon-Ho
    • Journal of Preventive Medicine and Public Health
    • /
    • v.23 no.3 s.31
    • /
    • pp.285-295
    • /
    • 1990
  • The utilization of medical care services has been partly regionalized with the implementation of referral requirement by the government since July 1, 1989 when the health insurance coverage was extended to all the people. For the purpose of regionalization, the whole country has been primarily divided into tertiary care regions, and each of them again into secondary care regions. This study investigates the self-sufficiency for in-patient care services of secondary care regions focusing on why it varies among the regions. In doing so, analysis is performed to examine a model which embodies three sets of hypotheses as follows : 1) The regional self-sufficiency for medical care services would be subject to direct influences of regional characteristics, amount of available services and structural properties of regional medical care system ; 2) The regional characteristics would have indirect effects on the self-sufficiency which are mediated by medical care services ; and 3) The amount of available services would indirectly affect the self-sufficiency by influencing the structure of regional medical care system. The results of analysis were generally consistent with the model. The findings have some practical implications. The regional self-sufficiency for medical care services partly depends upon basic properties of each region which cannot be changed in a short period of time. Thus the self-sufficiency for medical care services can be improved mainly by health policy measures. In some of the regions the self-sufficiency for in-patient care services was much higher or lower than can be predicted from the bed-population ratio. Indication is that the allocation of health resources should be made considering a variety of factors bearing upon the supply of and demand for health care ; not on the basis of just a single criterion like the availability. The self-sufficiency of a certain region is related to not only its own characterstics but also the characteristics of neighboring regions. Therefore, attention should be also directed to the inter-regional relationships in health care when the needs for investment of health resources in a region are assessed. However, it should be noted that this study used the data collected before the referral requirement was imposed. A replication of this analysis using recent data would provide an evaluation of the impact on the self-sufficiency of the referral requirement as well as a confirmation of the findings of this study.

  • PDF

A model of Photon Dominated Region(PDR) for the UV-heated outflow walls in the embedded protostellar objects

  • Lee, Seok-Ho;Lee, Jeong-Eun;Park, Yong-Sun
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.37 no.1
    • /
    • pp.83.1-83.1
    • /
    • 2012
  • We have developed an self-consistent PDR model to synthesize warm CO lines of Herschel/PACS observations more accurately. The PDR model solves the FUV continuum radiative transfer, gas energetics, and chemistry simultaneously. A local FUV radiation flux is calculated by using a Monte Carlo method taking anisotropic scattering into account. A new (r, ${\delta}$) coordinate system was used, where the r is the distance from the origin and the ${\delta}$ is z/$R^2$ in the cylindrical coordinate of (R,z). This is an adequate coordinate system to represent a power-law density of an envelope and a high spatial resolution near the outflow wall. The gas enegetics and chemistry are solved locally and considered $10^4K$ blackbody radiation field instead of the interstellar radiation filed. This newly developed model can be used to analyze quantitatively the effect of UV-heated outflow walls on the warm molecular lines in the embedded proto-stellar objects.

  • PDF

Numerical analysis of particle transport in low-pressure, low-temperature plasma environment

  • Kim, Heon Chang
    • Particle and aerosol research
    • /
    • v.5 no.3
    • /
    • pp.123-131
    • /
    • 2009
  • This paper presents simulation results of particle transport in low-pressure, low-temperature plasma environment. The size dependent transport of particles in the plasma is investigated with a two-dimensional simulation tool developed in-house for plasma chamber analysis and design. The plasma model consists of the first two and three moments of the Boltzmann equation for ion and electron fluids respectively, coupled to Poisson's equation for the self-consistent electric field. The particle transport model takes into account all important factors, such as gravitational, electrostatic, ion drag, neutral drag and Brownian forces, affecting the motion of particles in the plasma environment. The particle transport model coupled with both neutral fluid and plasma models is simulated through a Lagrangian approach tracking the individual trajectory of each particle by taking a force balance on the particle. The size dependant trap locations of particles ranging from a few nm to a few ${\mu}m$ are identified in both electropositive and electronegative plasmas. The simulation results show that particles are trapped at locations where the forces acting on them balance. While fine particles tend to be trapped in the bulk, large particles accumulate near bottom sheath boundaries and around material interfaces, such as wafer and electrode edges where a sudden change in electric field occurs. Overall, small particles form a "dome" shape around the center of the plasma reactor and are also trapped in a "ring" near the radial sheath boundaries, while larger particles accumulate only in the "ring". These simulation results are qualitatively in good agreement with experimental observation.

  • PDF

A 3-DOF forced vibration system for time-domain aeroelastic parameter identification

  • Sauder, Heather Scot;Sarkar, Partha P.
    • Wind and Structures
    • /
    • v.24 no.5
    • /
    • pp.481-500
    • /
    • 2017
  • A novel three-degree-of-freedom (DOF) forced vibration system has been developed for identification of aeroelastic (self-excited) load parameters used in time-domain response analysis of wind-excited flexible structures. This system is capable of forcing sinusoidal motions on a section model of a structure that is used in wind tunnel aeroelastic studies along all three degrees of freedom - along-wind, cross-wind, and torsional - simultaneously or in any combination thereof. It utilizes three linear actuators to force vibrations at a consistent frequency but varying amplitudes between the three. This system was designed to identify all the parameters, namely, aeroelastic- damping and stiffness that appear in self-excited (motion-dependent) load formulation either in time-domain (rational functions) or frequency-domain (flutter derivatives). Relatively large displacements (at low frequencies) can be generated by the system, if required. Results from three experiments, airfoil, streamlined bridge deck and a bluff-shaped bridge deck, are presented to demonstrate the functionality and robustness of the system and its applicability to multiple cross-section types. The system will allow routine identification of aeroelastic parameters through wind tunnel tests that can be used to predict response of flexible structures in extreme and transient wind conditions.

Peer and Parental Influences on Adolescent Smoking

  • Lee Eunyoung;Tak Youngran
    • Journal of Korean Academy of Nursing
    • /
    • v.35 no.4
    • /
    • pp.694-700
    • /
    • 2005
  • Purpose. The purpose of this study was to determine the relationship between peer and parental factors and smoking behavior of adolescents in urban cities and to investigate whether there are gender differences. Methods. A stratified and random cluster sampling design was used to obtain a cross-sectional sample of high school students in two urban cities. The sample consisted of 512 Korean adolescents (256 boys and 256 girls) aged 15 to 18 (mean age 16.7$\pm$.58). Self-reported questionnaire consisted of adolescent smoking behavior, peer smoking and alcohol use, parental smoking and alcohol use, father-mother-peer relationships and perceived social support from peers and parents. Multiple logistic regression analysis was used to examine the hypothesized model. Results. The findings showed that peer and parental factors accounted for $30.3\%$ of the variance in adolescent smoking and peer smoking was most strongly associated with adolescent smoking behavior (OR = 10.18). In addition, peer smoking (OR = 4.71), peer alcohol use (OR = 4.21), and peer relationships (OR = 1.03) were significantly associated with boys' smoking behavior. In girls, peer smoking (OR = 26.50) and parent smoking (OR = 5.48) were significantly associated with smoking behavior. Conclusions. Consistent with previous findings, peer smoking is a significant factor on adolescent smoking. Specifically, boys would be more influenced from peers than girls. Therefore, smoking prevention programs for adolescents might be focused on the social context such as, resisting to peer pressure and enhancing the self-efficacy to control.