• Title/Summary/Keyword: Scale Effects

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C-V Characteristics in Nanometer Scale MuGFETs with Considering Quantum Effects (양자 현상을 고려한 나노미터 스케일 MUGFETS의 C-V 특성)

  • Yun, Se-Re-Na;Yu, Chong-Gun;Park, Jong-Tae
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.11
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    • pp.1-7
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    • 2008
  • In this work, a two dimensional, self-consistent Poisson-$Schr{\ddot{o}}dinger$ solver has been implemented to study C-V characteristics in nanometer scale MuGFETs with considering quantum effects. The quantum-mechanical effects on gate-channel capacitance for different device dimension and gate configurations of nanometer scale MuGFETs have been analyzed. It has been found that 4he gate-channel capacitance per unit gate area is increased as the device dimension decreases. For different gate configurations, the gate-channel capacitance is decreased with increase of effective gate number. Those resu1ts have been explained by the distribution profile of electron concentration in the silicon surface and inversion capacitance. The length of inversion-layer centroid has been calculated from inversion capacitance with device dimension and gate configurations.

A Criticality Analysis of the GBC-32 Dry Storage Cask with Hanbit Nuclear Power Plant Unit 3 Fuel Assemblies from the Viewpoint of Burnup Credit

  • Yun, Hyungju;Kim, Do-Yeon;Park, Kwangheon;Hong, Ser Gi
    • Nuclear Engineering and Technology
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    • v.48 no.3
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    • pp.624-634
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    • 2016
  • Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that $k_{eff}$ values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

Biaxial buckling analysis of sigmoid functionally graded material nano-scale plates using the nonlocal elaticity theory (비국소 탄성이론을 이용한 S형상 점진기능재료 나노-스케일 판의 이축 좌굴해석)

  • Lee, Won-Hong;Han, Sung-Cheon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.11
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    • pp.5930-5938
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    • 2013
  • The sigmoid functionally graded mateiral(S-FGM) theory is reformulated using the nonlocal elatictiry of Erigen. The equation of equilibrium of the nonlocal elasticity are derived. This theory has ability to capture the both small scale effects and sigmoid function in terms of the volume fraction of the constituents for material properties through the plate thickness. Navier's method has been used to solve the governing equations for all edges simply supported boundary conditions. Numerical solutions of biaxial buckling of nano-scale plates are presented using this theory to illustrate the effects of nonlocal theory and power law index of sigmoid function on buckling load. The relations between nonlocal and local theories are discussed by numerical results. Further, effects of (i) power law index, (ii) length, (iii) nonlocal parameter, (iv) aspect ratio and (v) mode number on nondimensional biaxial buckling load are studied. To validate the present solutions, the reference solutions are discussed.

Development and Effects of an Instructional Coaching Program Regarding Children with Attention Deficit Hyperactivity Disorder for Elementary School Teachers (초등 교사를 위한 ADHD 아동 교수법 코칭 프로그램 개발 및 효과)

  • Park, Shin Jeong;Park, Wan Ju
    • Journal of Korean Academy of Nursing
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    • v.47 no.3
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    • pp.305-318
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    • 2017
  • Purpose: The aim of this study was to identify the effects of a newly developed instructional coaching program regarding Attention Deficit Hyperactivity Disorder (ADHD) for teachers. Methods: Seventy teachers participated in this study involving a nonequivalent control group and a pretest-posttest design. The instructional coaching program consisted of eight 60-minute sessions. The program was developed through a theoretical development program involving six steps. To evaluate the effects of the program, data were collected through self-report questionnaires including the Knowledge Scale of Attention Deficit Disorder, Attitude Scale of Primary School Teachers Experiencing Students with ADHD, Practice Scale of Educational Intervention Activity, and the Korean ADHD Rating Scale. Data were analyzed with an independent t test, a chi-square test, and an ANCOVA using SPSS WIN version 20. Results: The intervention program consisted of 3 sectors, 8 subjects, and 24 content items. The experimental group showed a significant improvement in attitudes toward ADHD (F=22.83, p<.001). In addition, teacher's knowledge regarding ADHD (F=7.16, p=.010) and the implementation of instructional interventions (F=4.29, p=.043) improved. Further, teachers reported a reduction in children's ADHD-related behavior (F=4.34, p=.041). Results showed that the coaching program made a positive contribution to teaching skills and understanding of school-age children with ADHD. Conclusion: The instructional coaching program was well structured and significantly improved not only teachers'attitudes, knowledge, and teaching skills but also the behavior of children with ADHD in class. Therefore, the program is recommended as a means of facilitating teaching and managing children with ADHD in class.

A Comparison of Patient-Controlled Analgesia and Conventional Intramuscular Opioid Regimen in Relation to their Post-Operative Pain Control and Side Effects (수술후 통증 관리의 Patient-Controlled Analgesia와 마약류의 전통적인 근육내 주사와의 비교)

  • Lee, Sang-Hun;Lee, Jin-Kyung;Lee, Kyn-Chang;Woo, Nam-Sik;Lee, Ye-Chul
    • The Korean Journal of Pain
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    • v.6 no.1
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    • pp.55-59
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    • 1993
  • Using a visual analogue scale, we compare the effect of patient-controlled analgesia and conventional intramuscular opioid regimen in 68 patients undergoing lower abdominal or gynecological surgery. We also recorded the incidence of side effects. We checked visual analogue scale 4 hours interval for 30 cases managed by patient-controlled analgesia and 38 cases of conventional intramuscular opioid group managed by obstetrician. We maintained fentanyl $0.33{\mu}g/kg/hr$ and set self administrable bolus dose $5.0{\mu}g$(lockout interval: 15 min) in patient-controlled analgesia group. Conventional intramuscular bolus injection group were administered meperidine 50 mg for 4 hour interval. Mean visual analogue scale scores obtained by patient-controlled analgesia group and intramuscular bolus injection group were $2.49{\pm}0.67$ and $4.53{\pm}1.28$(p<0.05). Side effects such as; no significant incidence of respiratory depression, urinary retention, postural hypotension, nausea, vomiting and pruritus were developed by either group. These results suggest that patient-controlled analgesia was more effective method compared with conventional intraumuscular opioid injection regimen for post-operative pain management.

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The Effects of Mindfulness Meditation on Anger according to Sasang Constitution (사상체질에 따라 마음챙김 명상이 분노에 미친 영향 연구)

  • Bae, Hyo-Sang;Park, Seo-Yeon;Jeong, Jun-Young;Park, Seong-Sik
    • Journal of Sasang Constitutional Medicine
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    • v.26 no.2
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    • pp.133-145
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    • 2014
  • Objectives In this study, we tried to examine that Sasang Constitutional differences affect the direction of the treatment of anger by comparing the effect of mindfulness meditation for anger scale in accordance with the difference of the constitution. Methods We analysed 105 college student's Constitution by Questionnaire for the Sasang Constitution Classification II and the effect of mindfulness meditation for anger by State-Trait Anger Expression Inventory Korean version(STAXI-K), Korean Version of the Behavioral Anger Response Questionnaire(K-BARQ). Volunteers who participated in this study were 105 people, except for person that did not properly entered the anger scale and Questionnaire for the Sasang Constitution Classification II, the subjects of analysis for State-Trait Anger Expression Inventory Scale were 45 and for the Behavioral Anger Scale were 49. Results & Conclusions The result of the effects of mindfulness meditation according to Sasang Constitution was as follows. The tendency to try to disperse and avoid the anger was increased through meditation for all subjects. The diffusion of male subjects and the avoidance of female subjects was increased. The effect of meditation on anger did not differ according to Sasang Constitution, constitutional differences did not affect the effects of meditation. The tendency of avoidance of anger was increased in Soyangin, Anger-out was decreased and the tendency of avoidance and diffusion of anger were decreased in Taeeumin through meditation.

Nonlocal elasticity effects on free vibration properties of sigmoid functionally graded material nano-scale plates (S형상 점진기능재료 나노-스케일 판의 자유진동 특성에 미치는 비국소 탄성 효과)

  • Kim, Woo-Jung;Lee, Won-Hong;Park, Weon-Tae;Han, Sung-Cheon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.1109-1117
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    • 2014
  • We study free vibration analysis of sigmoid functionally graded materials(S-FGM) nano-scale plates, using a nonlocal elasticity theory of Eringen in this paper. This theory has ability to capture the both small scale effects and sigmoid function in terms of the volume fraction of the constituents for material properties through the plate thickness. Numerical solutions of S-FGM nano-scale plate are presented using this theory to illustrate the effect of nonlocal theory on natural frequency of the S-FGM nano-scale plates. The relations between nonlocal and local theories are discussed by numerical results. Further, effects of (i) power law index (ii) nonlocal parameters, (iii) elastic modulus ratio and (iv) thickness and aspect ratios on nondimensional frequencies are investigated. In order to validate the present solutions, the reference solutions are compared and discussed. The results of S-FGM nano-scale plates using the nonlocal theory may be the benchmark test for the free vibration analysis.

Analysis of Income Variation of Professional Rice Cultivators Supported by the Farmland Scale Improvement Project (영농규모화사업의 지원을 받은 쌀전업농가의 소득분석)

  • Kim, Kyung-Jin;Kim, Jai-Hong
    • Korean Journal of Agricultural Science
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    • v.34 no.2
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    • pp.189-200
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    • 2007
  • The purpose of this study is to evaluate the farmland scale improvement project and to present basic data for establishing a long-term improvement scheme of this project. Professional rice cultivators' farming scale after receiving the farmland scale improvement fund has increased compared to the situation before receiving the fund support. The average paddy fields increased by 220% (from 2.75ha to 8.82ha), the average upland increased by 27% (from 0.44ha to 0.56ha), and the average orchard land increased by 44% (from 0.25ha to 0.36ha). The rice production costs per 10a are estimated as 608,678won for below 3ha, 488,721won for 3-6ha, 487,431won for 6~10ha, and 425,313won for over 10ha, which decreased with increasing farming scale. The effects of the farmland scale improvement project on income variation are summarized as follows. 1) Average farm household income for all subjects has increased by 223 % (from 40,517,000won to 90,295,000won). 2) For each category, the results show that average farm household income has increased by 9,766,000won for below 3ha, 35,898,000won for 3~6ha, 42,822,000won for 6~10ha, and 72,697,000won for over 10ha.

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Self-Actualization of College Students in Distance Education Analyzed from Nursing Counseling (정신간호상담에서 나타난 방송통신 대학생의 자아실현 분석)

  • 이소우;박명자
    • Journal of Korean Academy of Nursing
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    • v.17 no.1
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    • pp.33-43
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    • 1987
  • This study was to explore the level of self-actualization of the students in Korea Air and Correspondence University. The study subjects consisted of 507 students who visited the counseling center for taking advices to several psychosocial problems due to distance education through nursing counseling. The self actualization of the subjects evaluated by the self-actualization Inventory standardized by Kim and Lee in Korea. It consisted of 130 two-choice comparative value and behavior judgements. The items also consisted of two basic scales: one is inner directed scale (107 items) and the other is time competence (23 items) which included eight subscales, each of which measures a conceptually important element of self-actualization. Analysis of finding was as follows: 1) The self-actualization mean score of the total subjects was characterized by normal value within normal range of scale. The highest subscale score was NC scale: the lowest scale was EX scale. 2) The mean score of time competence scale of female student was higher than male student's time competence scale. 3) There was no significant differences in self aclualization among 4 groups in age. 4) There was also no significant differences in self-actualization between the group taken one time nursing counseling and the group taken two more times nursing counseling. 5) The problems of Job, learning, personality and further study, significantly had effects on the score of self-actualization level.

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Load and Stiffness Dependence of Atomistic Sliding Friction (원자스케일 마찰의 하중 및 강성 의존성)

  • Sung, In-Ha
    • Tribology and Lubricants
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    • v.23 no.1
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    • pp.9-13
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    • 2007
  • Despite numerous researches on atomic-scale friction have been carried out for understanding the origin of friction, lots of questions about sliding friction still remain. It is known that friction at atomic-scale always shows unique phenomena called 'stick-slips' which reflect atomic lattice of a scanned surface. In this work, experimental study on the effects of system stiffnesses and load on the atomic-scale stick-slip friction of graphite was performed by using an Atomic Force Microscope and various cantilevers/tips. The objective of this research is to figure out the dependency of atomic-scale friction on the nanomechanical properties in sliding contact such as load, stiffness and contact materials systematically. From this work, the experimental observation of transitions in atomic-scale friction from smooth sliding to multiple stick-slips in air was first made, according to the lateral cantilever stiffness and applied normal load. The superlubricity of graphite could be verified from friction vs. load experiments. Based on the results, the relationship between the stickslip behaviors and contact stiffness was carefully discussed in this work. The results or this work indicate that the atomic-scale stick-slip behaviors can be controlled by adjusting the system stiffnesses and contact materials.