• Title/Summary/Keyword: well-mixed area

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Body Measurement Changes and Prediction Models for Flight Pilots in Dynamic Postures (자세에 따른 부위별 체표길이 변화량 분석 및 예측모형 개발 -공군 전투조종사를 대상으로-)

  • Lee, Ah Lam;Nam, Yun Ja;Chen, Lin
    • Journal of the Korean Society of Clothing and Textiles
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    • v.44 no.1
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    • pp.84-95
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    • 2020
  • Wearing ease is a critical factor when designing special uniforms such as flight pilot's garment and should reflect occupational properties for better performance. This study measured skin surface on 31 areas in seven postures that refer to the pilot's occupational postures as well as made six prediction models including linear mixed model (LMM) for each body part to find the best fit model. Skin surface measured from 3D body scanned images of 11 male pilot participants. There were significantly positive and negative changes in various areas from standing posture (P1) to dynamic postures (P2-P7). Six models were designed in various compositions using stature and chest circumference as fixed effects and subject and posture as random effects. The best models were linear mixed models with one fixed effect (chest circumference or stature, varies with body parts) and two random effects (subject and posture). The results of this study provide reference data to set wearing ease for pilot's garment and suggests a new methodology in this research area, but verifying the effect of diverse independent variables is left for future studies.

Catalytic Characteristics of Perovskite-type Oxides under Mixed Methane and Oxygen Gases (메탄-산소 혼합가스 조건에서의 페롭스카이트계 산화물의 촉매특성 평가)

  • Ahn, Ki-Yong;Kim, Hyoung-Chul;Chung, Yong-Chae;Son, Ji-Won;Lee, Hae-Won;Lee, Jong-Ho
    • Journal of the Korean Ceramic Society
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    • v.45 no.4
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    • pp.232-237
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    • 2008
  • As the single chamber SOFC(SC-SOFC) showed higher prospect on reducing the operation temperature as well as offering higher design flexibility of SOFCs, lots of concerns have been given to investigate the catalytic activity of perovskite-type oxide in mixed fuel and oxidant conditions. Hence we thoroughly investigated the catalytic property of various perovskite-type oxides such as $La_{0.8}Sr_{0.2}MnO_3(LSM),\;La_{0.6}Sr_{0.4}CoO_3(LSC),\;La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_3(LSCF),\;Sm_{0.5}Sr_{0.5}CoO_3(SSC),\;and\;Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}(BSCF)$ under the partial oxidation condition of methane which used to be given for SC-SOFC operation. In this study, powder form of each perovskite oxides whose surface areas were controlled to be equal, were investigated as functions of methane to oxygen ratios and reactor temperature. XRD, BET and SEM were employed to characterize the crystalline phase, surface area and microstructure of prepared powders before and after the catalytic oxidation. According to the gas phase analysis with flow-through type reactor and gas chromatography system, LSC, SSC, and LSCF showed higher catalytic activity at fairly lower temperature around $400^{\circ}C{\sim}450^{\circ}C$ whereas LSM and BSCF could be activated at much higher temperature above $600^{\circ}C$.

Feeding strategies with total mixed ration and concentrate may improve feed intake and carcass quality of Hanwoo steers

  • Lee, Soohyung;Lee, Sang Moo;Lee, Jaehun;Kim, Eun Joong
    • Journal of Animal Science and Technology
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    • v.63 no.5
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    • pp.1086-1097
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    • 2021
  • This study examined the impact of using total mixed ration (TMR) and concentrate on feed intake, daily gain, carcass yield grade, and carcass quality grade of Hanwoo steers and its subsequent economic efficiency. Thirty six 7-month-old Hanwoo steers were assigned to one of the four treatment groups, and each group was divided into three repeated pens, with each repeated pen comprising three steers. The treatment groups were: 1) separate feeding with commercial concentrate and forage (namely, SCF) for the entire experimental period; 2) TMR feeding for a growing period followed by SCF for the early and late fattening period (namely, TMRGSCF); 3) TMR feeding for growing and an early fattening period followed by SCF for the late fattening period (namely, TMREFSCF); and 4) TMR feeding for the entire experimental period (namely, TMRW). The results showed that the SCF treatment had significantly (p < 0.05) higher feed intake during the growing period than other treatments. In contrast, the total feed intake had little difference during early and late fattening as well as the whole period regardless of feeding strategies. Daily gain showed no difference during the growing period. However, it was significantly higher in SCF and TMREFSCF treatments for the early and late fattening period, respectively (p < 0.05). The daily gain during the total raising period is in the order of TMREFSCF > TMRGSCF > SCF > TMRW. Carcass characteristics, including carcass weight, loin eye muscle area, and carcass yield grade, did not significantly differ among different treatments. However, TMRW treatment, wherein TMR was fed for a long time, showed that the cold carcass weight was less compared with other treatments, but carcass yield grade was higher with thinner backfat. Backfat thickness was in the order of SCF > TMRGSCF > TMREFSCF > TMRW, showing that the thickness reduced with longer TMR feeding (p < 0.05). TMRGSCF, which numerically had a higher carcass quality grade, showed higher economic efficiency, whereas SCF showed low economic efficiency. In conclusion, it was more feasible to apply TMR strategy in the growing and early fattening period and then SCF for the early or late fattening period to improve carcass yield, quality grade, and economic efficiency.

The Strategy of Russia's Political Elites to Maintain Dominance Through the Overhaul of Electoral System (선거제도 개편을 통한 러시아 정치 엘리트의 지배력 유지 전략)

  • Siheon Kim;Seho Jang
    • Analyses & Alternatives
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    • v.7 no.1
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    • pp.7-43
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    • 2023
  • This study examines and identified a series of strategies of Russia's political elites to maintain and strengthen their dominance by reviewing the case of revisions in the election laws of Russia in 2014. At that time, a mixed-member electoral system was newly introduced, and on the surface, it seemed that the new system was a step toward meeting the demands of the people for "enhanced democracy". However, in 2016 and 2021, the ruling party of Russia won the general elections by making the most of the factors that could distort the election results inherent in the mixed-member electoral system. Therefore, this study aimed to analyze whether the revision of election laws was a mere vehicle used by the ruling party, United Russia, to maintain its political power, or whether it was a leap forward to achieve democracy. The study result indicate that the revision of election laws in 2014 was part of the policy responses to the internal conflicts in the circle of Russia's political elites, which had been rising since 2008, as well as to the public resistance. In other words, it was confirmed that the revision of election laws was one of the measures taken to "minimize competition" and "reproduce political power on a stable basis".

A Study on the Development of Predictive Model for Patient Visibility in Korean Intensive Care Units (ICUs) - Focused on "Corridor or Continental" type units

  • Ullah, Ubaid;Park, Jae Seung
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.22 no.3
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    • pp.27-34
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    • 2016
  • Purpose: The purpose of this paper is to develop a predictive model for patient visibility in Korean ICUs (corridor or continental type). Methods: The measures of static visibility were used to quantify the patient visibility (upper third part of the patient bed) from the nurse station. The measure of space programme and area distribution (patient zone percentage, staff zone percentage and departmental gross square meter per patient bed) were calculated by using AutoCAD and MS Excel programs. Regression analysis was conducted for visibility as dependant variable with independent variables of patient area percentage, staff area percentage as well as departmental gross square meter per bed by using IBM SPSS. Results: (1) Average patient visibility and percentage of patient area in ICU shows a strong negative correlation ($r^2$=0.66), p=0.01. (2) Patient visibility in Korean ICU (corridor or continental type) can be calculated as below with the given conditions: Y= $-1.449(X)+124.3{\pm}6$, Y is the total visibility of the ICU (corridor or continental type) and X is the percentage of patient area in the unit. Conditions:1. Given that the unit has a mixed programme of open bed and closed patient rooms and 2. The unit have a minimum of 20% patient rooms. Implications: This study may contribute to the visibility analysis of existing and future ICU design (corridor or continental type) in Korea to achieve maximum patient visibility and reduced patient mortality.

Concentration Variations of Persistent Organic Pollutants in Gosan, Jeju during the Polluted Period in November 2001 and the Yellow Sand Period in Spring 2002 (2001년 11월 오염시기와 2002년 봄 황사시기 제주도 고산에서의 잔류성 유기오염물질 농도 변화)

  • 김영성;김진영;김연제;문길주;문광주;한진석;김상우;윤순창;권성안
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.5
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    • pp.469-490
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    • 2003
  • Atmospheric concentrations of persistent organic pollutants (POPs) were measured at Gosan, Jeju in November 2001 and spring 2002, each time for two weeks. Primary target pollutants were organochlorine pesticides, coplanar polychlorinated biphenyls (co- PCBs), and dioxin/furans listed in the Stockholm Convention adopted in May 2001. Polycyclic aromatic hydrocarbons (PAHs) were also measured in order to understand the overall characteristics of the POPs distribution as well as PM$_{2.5}$, a potent carrier of POPs. In the latter part of the measurement period of November 2001, almost every pollutant of combustion origin including dioxin/furans went high probably due to influence of emissions in the nearby area. The characteristics of atmospheric environment at Gosan in this period were rather close to urban areas far from those of a background area. A severe dust storm swept for three days at the end of the measurement period of spring 2002. However, changes in pollutant concentrations were relatively small except PM$_{10}$. Nevertheless, increases in particulate PAHs and OCDD (octachlorinated dibenzo-p-dioxins), mostly present in fine particles, were observed. Trends in organochlorine pesticide variations were mixed although possible volatilization of DDT residues from soil was inferred from the measurements of spring 2002.2.2.

The Oxidation of Magnetic Particles in Medicinal Ointment

  • Kim, Eng-Chan
    • Journal of Magnetics
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    • v.17 no.2
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    • pp.83-85
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    • 2012
  • Magnetic particles in a novel, wound-healing ointment were studied using M$\ddot{o}$ssbauer spectroscopy and VSM to estimate the stability of the properties of the magnetic particles. The isomer shifts of $Fe_3O_4(A)$ were found to be 0.49-0.56 mm/s relative to iron metal, this indicates that the iron ions in $Fe_3O_4(A)$ are $Fe^{3+}$. On the other hand, the isomer shifts of $Fe_3O_4(B)$ were found to be 0.91-1.13 mm/s relative to iron metal, this shows that the ion state of $Fe_3O_4(B)$ is a mixed state of $Fe^{2+}$ and $Fe^{3+}$. It is noted that this composition, as well as that of the initial pure component in the form of a highly dispersed fraction (${\sim}10\;{\AA}$), differs from the stoichiometric one. It was found that the area ratio of the M$\ddot{o}$ssbauer subspectra of $Fe_3O_4(A)$ / $Fe_3O_4(B)$ taken at 87 and 181 K linearly increased in comparison to the initial pure magnetic particles, but the rate of increase of the area ratio at 181 K was about two times that at 87 K. From the magnetic hyperfine field, despite their small size, the particles exhibit no superparamagnetism.

Conveniences & Inconveniences of Living in Residential Care Facilities Focused on Middle Class Paid Facilities in Rural Area- (양로원 생활의 장단점에 관한 연구 -농촌지역 중류층 유료시설을 중심으로-)

  • Lee, In-Soo
    • Journal of Families and Better Life
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    • v.20 no.5
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    • pp.113-124
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    • 2002
  • This study has been performed to explore conveniences and inconveniences of daily lives in rural residential care facilities among the elderly residents. In this study, five males and seven females aged 68 to 78 were asked about socio-familial and physical aspects of their daily lives in the facilities such as meals, social activities, family visits, recreation, and health care. The answers of the qualitative interview were drawn as follow; first, the residents perceived well planned regular meals and snacks, free visits of friends, regularly supervised daily sanitary activities, periodic outdoor activities, education programs provided by religious experts, and pastoral farming lives as most convenient aspects of the retirement facilities. In addition, some felt that facility life made them free of familial conflicts, while others appealed fear of being forgotten because of distant location. On the other hand, they perceived the supervised group activities and meals as major inconveniences. They also felt persistently depressed when closely observing serious illness or deaths of their co-residents. Therefore in this study, suggestions were made as follows: first, combination of normal family life and retirement facility should be developed in the mixed form of community welfare center and shared home. Second, intensive medical care facilities should be in collaboration with the retirement facilities, so that the residents are relieved from stressful contacts with extremely ill patients in the residential area.

Numerical Study on the Ventilation Performance in the Boiler Building with and without Roof Openings (루프 환기구에 따른 보일러빌딩 내부 환기성능에 관한 수치적 연구)

  • Choi, Hoon Ki;Yoo, Geun Jong;Lee, Sang Heon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.26 no.3
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    • pp.342-349
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    • 2016
  • Objectives: The objective of this paper is to find flow and heat transfer characteristics numerically in boiler buildings for three different ventilation window configurations. Methods: Turbulent natural convection flow in boiler buildings with a constant heating wall temperature was analyzed numerically. Governing equations were solved with standard finite-volume method using the SIMPLE algorithm. Conclusions: Flow and heat transfer characteristics are found for three different ventilation types. In the lower area under furnace, velocity and temperature distributions show similar patterns among the three different ventilation types. In the upper area over furnace, however, air flow is well mixed with lower peak temperatures for types B and C, which have roof ventilation windows, compared to type A which has side wall louvers only. Also, type B, with a single large roof window, shows better ventilation effect than does type C with its distribution roof windows.

An Evaluation of Listening Studies concerning Discourse Signaling Cues: Focus on Research Designs

  • Jung, Euen-Hyuk
    • English Language & Literature Teaching
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    • v.15 no.4
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    • pp.55-74
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    • 2009
  • Although a considerable amount of research on discourse signaling cues has been conducted in reading, little attention has been paid to such cues in the area of listening. Moreover, despite the solid evidence showing that cues have beneficial effects for reading comprehension, L2 listening research has produced mixed findings about the role of cues. Such discrepancies among these findings might be due in part to inadequate research methodologies as well as the idiosyncratic features of their experimental designs. However, no study, to date, has thoroughly examined the research designs of listening comprehension studies on cues. Consequently, this study critically evaluates the present state of research designs and reporting practices of studies investigating the role of cues in listening comprehension. The present study aims to provide insights into areas that require empirical attention and systematic investigation. It also seeks to encourage improved and refined research practices for future studies. This paper is organized as follows: It will first critically review the empirical findings regarding cues in the area of L1 listening comprehension. Second, it will present a critical evaluation of L2 listening studies on cues. Finally, it will address the major research design issues of currently available listening studies and provide suggestions for improvement in future research.

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