• Title/Summary/Keyword: Reflection Rate

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Satisfaction with School Food Service of Middle School Students in Daegu (대구지역 중학생들의 학교 급식 만족도 조사)

  • Jang Mi-Ae;Choi Mi-Ja
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.2
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    • pp.226-234
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    • 2005
  • A study was conducted to improve satisfaction to school food service and to furnish source materials for nutrient education by researching degree of satisfaction of middle school students to school food service. Following results are from the study that targeted 215 male students and 173 female students in 5 middle schools in Daegu. Satisfaction rates regarding taste of foods, smell, proper temperature, use of seasonal food, cafeteria atmosphere, numbers of side dishes, and kindness of the cook in a cafeteria were higher than dissatisfaction. And dissatisfaction rates were higher in quantity and quality of foods, sanitation, purity of table wares, opening to nutrient education and related informations for students, opinion reflection of students, food serving time and gratification to food serving than the opposite. But the degree of general satisfaction on school food service were higher than the degree of general dissatisfaction. Sanitation was the first thing to be changed in school food service, then quantity of food and taste for the last. And there were notable differences between male students and female students in sanitation satisfaction. The variables that influence on satisfaction to school food service were sanitary administration, numbers of side dishes, quantity of foods, nutrient, smell and taste when ranked. And the main three things that have similar rate in quantity with satisfaction rate are taste, smell and nutrient of school food service. Through these followed results, degree of general satisfactions to school food service were higher than degree of general dissatisfactions. But sanitation, quantity and quality of foods, taste, and food serving size were not satisfactory for students in rate. Therefore it has to be improved to enhance satisfactions to middle school food service.

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Particle Image Velocimetry of the Blood Flow in a Micro-channel Using the Confocal Laser Scanning Microscope

  • Kim, Wi-Han;Kim, Chan-Il;Lee, Sang-Won;Lim, Soo-Hee;Park, Cheol-Woo;Lee, Ho;Park, Min-Kyu
    • Journal of the Optical Society of Korea
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    • v.14 no.1
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    • pp.42-48
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    • 2010
  • We used video-rate Confocal Laser Scanning Microscopy (CLSM) to observe the motion of blood cells in a micro-channel. Video-rate CLSM allowed us to acquire images at the rate of 30 frames per second. The acquired images were used to perform Particle Image Velocimetry (PIV), thus providing the velocity profile of the blood in a micro-channel. While previous confocal microscopy-assisted PIV required exogenous micro/nano particles as the tracing particles, we employed blood cells as tracing particles for the CLSM in the reflection mode, which uses light back-scattered from the sample. The blood flow at various depths of the micro-channel was observed by adjusting the image plane of the microscope. The velocity profile at different depths of the channel was measured. The confocal micro-PIV technique used in the study was able to measure blood velocity up to a few hundreds ${\mu}m/sec$, equivalent to the blood velocity in the capillaries of a live animal. It is expected that the technique presented can be applied for in vivo blood flow measurement in the capillaries of live animals.

The cultural characteristic of American film (genre drama) in (영화 <블라인드 사이드 Blind Side>에 나타난 '드라마' 장르의 미국 문화 특성)

  • Han, Yong Taek;Woo, Jung Gueon
    • Cross-Cultural Studies
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    • v.26
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    • pp.273-296
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    • 2012
  • The purpose of this paper is to examine the characteristics of American film (genre drama) through the analysis of , which merits our attention because the proportion of domestic gross earnings to foreign gross earnings is four to one. It means that the cultural discount rate of this film is relatively higher than the films which belong to the other genres, for example adventure, action, fantasy, SF etc. And it would be correct to say that this film is typically american. What is the reason of this difference of cultural discount rate? And what allows this film to be defined as a typical American film. The analysis of shows that the difference doesn't result from the actant structure. In fact the narrative structure of this film is similar to the other films of drama genre like or : the common structure of drama genre is characterized by an encounter of sujet and adjuvant and the progress of their relationship. But the drama is a genre in which the reflection of the actualities is important as compared with other genres. In that sense the story of is based upon the American cultural characteristics. Because the process that realize the progress of relationship between two protagonists is typically American such as race problem, adoption system, concept of family, system of education and going to college etc. As a result it is possible that move less the worldwide spectators than the American spectators.

Development of a Demand Model for Physician Workforce Projection on Regional Inequity Problem in Korea Using System Dynamics (시스템 다이내믹스를 활용한 지역별 국내 의사인력 수요에 대한 추계모델 개발)

  • Lee, Gyeong Min;Yoo, Ki-Bong
    • Health Policy and Management
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    • v.32 no.1
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    • pp.73-93
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    • 2022
  • Background: Appropriate physician workforce projection through reasonable discussions and decisions with a broad view on supply and demand of the workforce, thus, is very important for high-quality healthcare services. The study expects to provide preliminary research data on the workforce diagnosis standard model for Korean physician workforce policy decision through more flexible and objective physician workforce projection in reflection of diverse changes in healthcare policy and sociodemographic environments. Methods: A low flow rate through the causal map was developed, and an objective workforce demand projection from 2019 to 2040 was conducted. In addition, projections by scenarios under various situations were conducted with the low flow rate developed in the study. Lastly, the demand projection of the physician workforce by region of 17 cities and provinces was conducted. Results: First, demand of physicians in 2019 was 110,665, 113,450 in 2020, 129,496 in 2025, 146,837 in 2030, 163,719 in 2035, and 179,288 in 2040. Second, the scenario for the retirement of baby boomers led to a decrease in the growth rate due to time delay. Third, Seoul and Gyeonggi-do account for a high percentage of demand, a very high upward trend was identified in Gyeonggi-do, and as a result, the projection showed that the demand of the physician workforce in Gyeonggi-do would worsen over time. Conclusion: This study is meaningful in that rational and collective physician workforce supply and demand and its imbalance in workforce distribution were verified through various projections by scenarios and regions of Korea with System Dynamics.

A Case Study on the Implement of Teaching and Learning Models aiming at Training Creative Engineers: focused on the SICAT

  • KWON, Sungho;OH, Hyunsook;KIM, Sungmi
    • Educational Technology International
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    • v.11 no.1
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    • pp.27-46
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    • 2010
  • The purpose of this paper is to apply the newly developed SICAT teaching and learning model to the actual scene of teaching and learning and draw a point of discussion for utilizing teaching and learning model, by uncovering the satisfaction of students and the inhibiting/facilitating elements when using the model. SICAT(Scientific Inquiry and Creative Activity with Technology; from here on SICAT), a teaching and learning model custom-built for engineering education, was developed, as more and more people paid attention to the demand for creative engineers. It was developed from the basis of PBL(Problem Based Learning), includes three sub-types which can be applied to the actual theory, design, and experimentation fields within engineering education. The three sub-types, which are ARDA(Analysis-Reasoning Activity & Discussion-Argumentation Activity), CoCD (Collaboration Activity & Capstone Design Activity), and ReSh(Reflection Activity & Sharing Activity), respectively support deductive and argumentation activities, creative design and collaboration activities, and retrospection and sharing activities. However, no research has been conducted to investigate whether or not there are inhibiting or facilitating elements in the application procedure, or what the rate of satisfaction for students is, when applying the SICAT model, which was newly developed to innovate existing engineering education, to the actual site of teaching and learning. Therefore, this research applied three types of SICAT teaching and learning models to the theory, design, and experimentation classes at the department of materials science and engineering at Hanyang University for eight weeks. After application, the students, teachers and tutors were surveyed and interviewed, and then the results analyzed in order to uncover inhibiting/facilitating elements and the rate of satisfaction. The satisfaction rate of students from the SICAT teaching and learning model was 3.78(in a perfect score of 5: The A type-3.65, The C type-3.80, The R type-3.90), and inhibiting/facilitating elements were drawn from the aspects of learning activities, support system. In conclusion, they can be contributed for implications of SICAT teaching and learning model universal use at engineering education in University.

A Study on Fast Iris Detection for Iris Recognition in Mobile Phone (휴대폰에서의 홍채인식을 위한 고속 홍채검출에 관한 연구)

  • Park Hyun-Ae;Park Kang-Ryoung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.2 s.308
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    • pp.19-29
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    • 2006
  • As the security of personal information is becoming more important in mobile phones, we are starting to apply iris recognition technology to these devices. In conventional iris recognition, magnified iris images are required. For that, it has been necessary to use large magnified zoom & focus lens camera to capture images, but due to the requirement about low size and cost of mobile phones, the zoom & focus lens are difficult to be used. However, with rapid developments and multimedia convergence trends in mobile phones, more and more companies have built mega-pixel cameras into their mobile phones. These devices make it possible to capture a magnified iris image without zoom & focus lens. Although facial images are captured far away from the user using a mega-pixel camera, the captured iris region possesses sufficient pixel information for iris recognition. However, in this case, the eye region should be detected for accurate iris recognition in facial images. So, we propose a new fast iris detection method, which is appropriate for mobile phones based on corneal specular reflection. To detect specular reflection robustly, we propose the theoretical background of estimating the size and brightness of specular reflection based on eye, camera and illuminator models. In addition, we use the successive On/Off scheme of the illuminator to detect the optical/motion blurring and sunlight effect on input image. Experimental results show that total processing time(detecting iris region) is on average 65ms on a Samsung SCH-S2300 (with 150MHz ARM 9 CPU) mobile phone. The rate of correct iris detection is 99% (about indoor images) and 98.5% (about outdoor images).

Numerical Analysis of Unstable Combustion Flows in Normal Injection Supersonic Combustor with a Cavity (공동이 있는 수직 분사 초음속 연소기 내의 불안정 연소유동 해석)

  • Jeong-Yeol Choi;Vigor Yang
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.05a
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    • pp.91-93
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    • 2003
  • A comprehensive numerical study is carried out to investigate for the understanding of the flow evolution and flame development in a supersonic combustor with normal injection of ncumally injecting hydrogen in airsupersonic flows. The formulation treats the complete conservation equations of mass, momentum, energy, and species concentration for a multi-component chemically reacting system. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations and detailed chemistry of H2-Air is considered. It also accommodates a finite-rate chemical kinetics mechanism of hydrogen-air combustion GRI-Mech. 2.11[1], which consists of nine species and twenty-five reaction steps. Turbulence closure is achieved by means of a k-two-equation model (2). The governing equations are spatially discretized using a finite-volume approach, and temporally integrated by means of a second-order accurate implicit scheme (3-5).The supersonic combustor consists of a flat channel of 10 cm height and a fuel-injection slit of 0.1 cm width located at 10 cm downstream of the inlet. A cavity of 5 cm height and 20 cm width is installed at 15 cm downstream of the injection slit. A total of 936160 grids are used for the main-combustor flow passage, and 159161 grids for the cavity. The grids are clustered in the flow direction near the fuel injector and cavity, as well as in the vertical direction near the bottom wall. The no-slip and adiabatic conditions are assumed throughout the entire wall boundary. As a specific example, the inflow Mach number is assumed to be 3, and the temperature and pressure are 600 K and 0.1 MPa, respectively. Gaseous hydrogen at a temperature of 151.5 K is injected normal to the wall from a choked injector.A series of calculations were carried out by varying the fuel injection pressure from 0.5 to 1.5MPa. This amounts to changing the fuel mass flow rate or the overall equivalence ratio for different operating regimes. Figure 1 shows the instantaneous temperature fields in the supersonic combustor at four different conditions. The dark blue region represents the hot burned gases. At the fuel injection pressure of 0.5 MPa, the flame is stably anchored, but the flow field exhibits a high-amplitude oscillation. At the fuel injection pressure of 1.0 MPa, the Mach reflection occurs ahead of the injector. The interaction between the incoming air and the injection flow becomes much more complex, and the fuel/air mixing is strongly enhanced. The Mach reflection oscillates and results in a strong fluctuation in the combustor wall pressure. At the fuel injection pressure of 1.5MPa, the flow inside the combustor becomes nearly choked and the Mach reflection is displaced forward. The leading shock wave moves slowly toward the inlet, and eventually causes the combustor-upstart due to the thermal choking. The cavity appears to play a secondary role in driving the flow unsteadiness, in spite of its influence on the fuel/air mixing and flame evolution. Further investigation is necessary on this issue. The present study features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the previous works. In particular, the oscillatory flow characteristics are captured at a scale sufficient to identify the underlying physical mechanisms. Much of the flow unsteadiness is not related to the cavity, but rather to the intrinsic unsteadiness in the flowfield, as also shown experimentally by Ben-Yakar et al. [6], The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The work appears to be the first of its kind in the numerical study of combustion oscillations in a supersonic combustor, although a similar phenomenon was previously reported experimentally. A more comprehensive discussion will be given in the final paper presented at the colloquium.

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Sintering Effects on Fe/Mo Ordering and Magnetoresistance in Double Perovskite Sr2FeMoO6

  • Kim, J;Park, B.J;Lee, B.W
    • Journal of Magnetics
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    • v.9 no.1
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    • pp.9-12
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    • 2004
  • We have investigated sintering effects on Fe/Mo ordering and magnetoresistance (MR) in double perovskite-reflection lines due to $Sr_2FeMoO_6$ (SFMO). Polycrystalline samples have been prepared by the conventional solid-state reaction by sintering in a stream of 5% $H_2/Ar$ gas. All samples are single phase and exhibit a series of superstructurecation ordering at Fe and Mo sites. As sintering temperature increases from 900 to $1300^{\circ}C$, the degree of Fe/Mo ordering increases from 82 to 92%, magnetization (15 K, 7 kOe) increases from 1.6 to 2.7 ${\mu}_B/f.u.,$ and Curie temperature increases at a rate of 4.3 K/% with the increase of Fe/Mo ordering ratio. The magnitude of MR measured at 5 K is 19% for sample prepared at $1000^{\circ}C$ with magnetic fields of 7 kOe. The observed MR is proportional to the square of magnetization indicating that the MR feature in SFMO is explained by the spin-polarized tunneling at grain boundaries.

Analysis of an Optimal Iterative Turbo Equalizer for Underwater Acoustic Communication (수중 음향통신에 적합한 최적의 반복기반 터보 등화기 분석)

  • Park, Tae Doo;Lee, Seong Ro;Kim, Beom Mu;Jung, Ji Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.3
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    • pp.303-310
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    • 2013
  • Underwater acoustic communication has multipath error because of reflection by sea-level and sea-bottom. The multipath of underwater channel causes signal distortion and error floor. In order to improve the performance, it is necessary to employ an iterative coding scheme. Among the iterative coding scheme, turbo codes and LDPC codes are dominant channel coding schemes in recent. This paper concluded that turbo coding scheme is optimal for underwater communications system in aspect to performance, coded word length, and equalizer combining. Also, we confirmed the performance in the environment of oceanic experimentation using turbo equalizer based on distance 5Km, data rate 1Kbps.

The Effect of Substrate DC Bias on the Low -Temperature Si homoepitaxy in a Ultrahigh Vacuum Electron Cyclotron Resonance Chemical Vapor Deposition (초고진공 전자 사이클로트론 화학 기상 증착 장치에 의한 저온 실리콘 에피 성장에 기판 DC 바이어스가 미치는 영향)

  • 태흥식;황석희;박상준;윤의준;황기웅;송세안
    • Journal of the Korean Vacuum Society
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    • v.2 no.4
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    • pp.501-506
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    • 1993
  • The spatial potential distribution of electron cyclotron resonance plasma is measured as a function of tehsubstrate DC bias by Langmuir probe method. It is observed that the substrate DC bias changes the slope of the plasma potential near the subsrate, resulting in changes in flux and energy of the impinging ions across plasma $_strate boundary along themagnetric field. The effect of the substrate DC bias on the low-temperature silicon homoepitaxy (below $560^{\circ}C$) is examine dby in situ reflection high energy electron diffraction (RHEED), cross-section transmission electron microscopy (XTEM),plan-view TEM and high resolution transmision electron microscopy(HRTEM). While the polycrystalline silicon layers are grow withnegative substrate biases, the single crystaline silicon layers are grown with negative substrate biases, the singel crystalline silicon layers are grown with positive substrate biases. As the substrate bias changes form negative to positive values, the growth rate decreases. It is concluded that the control of the ion energy during plasma deposition is very important in silicon epitaxy at low temperatures below $560^{\circ}C$ by UHV-ECRCVD.VD.

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