• Title/Summary/Keyword: $^{232}Th$

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U-Series Disequilibrium Dating and its Application to the Recent Sediment Dating from Sangback-do, Southern Sea of Korean Peninsula (우라늄계열(系列) 비평충(非平衝) 연대측정법(年代測定法)과 한반도(韓半島) 남해(南海) 상백도(上白島) 현생(現生) 퇴적층(堆積層)의 연대측정(年代測定)에 관(關)한 연구(硏究))

  • Jae, Won Mok;Lee, Chul;Park, Keung Shik;Choo, Seung Whan
    • Economic and Environmental Geology
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    • v.18 no.3
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    • pp.239-246
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    • 1985
  • Uranium-thorium separation technique from shallow sediment and ${\alpha}$-source electrodeposition technique are established in the present work, and uranium series disequilibrium dating method is applied to the quaternary piston core from Sangback-do, South Sea of Korean Peninsula. The age of the piston core (depth 200~300cm) sampled from Latitude $34^{\circ}06^{\prime}37^{{\prime}{\prime}}$, Longitude $127^{\circ}37^{\prime}37^{{\prime}{\prime}}$ was determined as ranging from $9.0{\pm}2.2$ to $22.9{\pm}3.3$ Ky B.P, i.e., Later Pleistocene, older than Holocene which was stratigraphically known in the previous study. The sedimentation rate in the area is regularly increased according to the depth of the sedimentation layer. Except a few split sections of the piston core the sedimentation rates are avarage 7.2cm/1,000 years. Where sedimentation layer is deeper, then sedimentation rate tend to be slower. It must be pointed in age calculation that initial $^{230}Th/^{234}U$ radioactivity ratio is much influenced when detrital material was introduced in the sample. The $^{230}Th/^{234}U$ activity ratio measured in the present work is 0.06 at $^{232}Th=0$, and this value shows higher analytical errors because of the low· radioactivity of $^{230}Th$ in the samples.

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Factors Influencing Exercise Compliance among Older Adults (일 지역 노인의 운동이행 영향요인 분석)

  • Ko, Young-Ji;Lee, Ju-Hee
    • Journal of muscle and joint health
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    • v.19 no.2
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    • pp.223-232
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    • 2012
  • Purpose: The purpose of this study was to examine the relationships among perceived health status, exercise self-efficacy, social support, and exercise compliance and factors influencing exercise compliance in older adults in an area. Methods: The sample consisted of 154 older adults who attended a senior welfare center in D metropolitan city. Data were collected from the 25th to the 31th of January in 2012. Results: The mean score for perceived health status was 2.94, 911.69 for exercise self-efficacy, 46.99 for social support, and 6.83 for exercise compliance. The highest score on social support domains was emotional support, followed by self-esteem, material, and informational support. There were significant correlations between perceived health status and exercise self-efficacy, between perceived health status and exercise compliance, between exercise self-efficacy and social support, between exercise self-efficacy and exercise compliance, between emotional support and exercise compliance. Findings of multiple regression indicated that only exercise self-efficacy significantly explained exercise compliance. Conclusion: Health care providers may need to develop various intervention program to promote exercise self-efficacy in order to influence on exercise compliance and adherence among older adults.

A Study on Development of Design Program for PCV Valve (PCV 밸브의 설계 프로그램 개발에 관한 연구)

  • Lee, Jong-Hoon;Islam, Md. Tajul;Lee, Yeon-Won;Kim, Young-Duk
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.228-232
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    • 2005
  • Automobiles are very important as modern society is developed. Increase of the number of the automobiles cause environmental problem, that is, air pollution. So, many countries are adopting a environmental law. Automobile manufacturing companies have developing methods to prevent air pollution with increase of the efficiency of automotive engines. PCV(Positive Crankcase Ventilation) system which is one of them is made by the closed loop that consists of combustion chamber, crankcase, manifold suction tube and manifold. PCV valve is attached on manifold tube to control the flowrate of blowby gas. PCV valve is an important part in this system but it is difficult to design PCV valve which satisfies the required flowrate of blowby gas. In this study, our purpose is to help a PCV valve designer with the development of a design program. We used 4th order Runge-Kutta method and Bernoulli's equation to analyze the spool dynamic motion. By the comparison between our program and experiment, we think that a PCV designer can use our program in their work place.

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Effect of Eating-Out Consumption Propensity on Selection Attributes for Dessert Cafe (외식소비성향이 디저트 카페 선택속성에 미치는 영향)

  • Yoon, Jung-Suk
    • Culinary science and hospitality research
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    • v.23 no.7
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    • pp.31-41
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    • 2017
  • The purpose of this study was to verify the relationship of eating-out consumption propensity and selection attributes by consumers have been used dessert cafe and to provide the useful data for efficient establishing marketing strategies to dessert cafe managers. This survey was conducted from 7th to 22th on April, 2017 and a total of 250 responses were distributed, of which 232 were used for analysis, after excluding responses containing missing data. The results from this study are as follows. First, it was found that eating out enjoyment pursuit type and health pursuit type had significant effects on menu and service factor of selection attributes for dessert cafe. Second, only eating out enjoyment pursuit type had significant effects on visual factor of selection attributes for dessert cafe. Third, only health pursuit type had significant effects on health menu factor of selection attributes for dessert cafe. Fourth, economic value pursuit type and atmosphere pursuit type had significant effects on price factor of selection attributes for dessert cafe. This study contributes to useful results for establishing efficient marketing strategies to dessert cafe marketers by examining selection attribution of dessert cafe as recognizing eating-out consumption propensity.

Fabrication of High Speed Modulation Doped SMQW-PBH-DFB-LD (변조 도핑된 SMQW-PBH-DFB-LD의 고속변조 특성)

  • 장동훈;이중기;조호성;박경형;김정수;박철순;김흥만;편광의
    • Korean Journal of Optics and Photonics
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    • v.6 no.3
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    • pp.228-232
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    • 1995
  • We have made modulation doped SMQW-PBH-DFB-LD for high speed optical communications. The waveguide and barrier layers were doped by Zn with the concentration of $1.2 \times 10^{18}cm^{-1}$. Mean threshold current and slope efficiency were 24.88 mA (minimum 16 mA) and 0.197 mW/mA (maximum 0.275 mW/mA) respectively. Linewidth enhancement factor ($\alpha$) of MD-SMQW-PBH-DFB-LD was reduced than that of SMQW-PBH-DFB-LD. Linewidth enhancement factor of 1.8 owes to the large gain coefficient of modulation doped active layer. The resonance frequency was linearly increased with the square root of optical power. The resonance frequency in small signal modulation was measured as 8 GHz and -3 dB modulation bandwidth was 10 GHzat $46mA(I_{th}+30mA)$..

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The Work Experiences of Emergency Room Nurses during the COVID-19 Pandemic (COVID-19 대유행 상황에서 응급실 간호사의 근무 경험)

  • Hyeon, Yong Hwan;Chae, Young Hee
    • Journal of Korean Clinical Nursing Research
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    • v.27 no.3
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    • pp.221-232
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    • 2021
  • Purpose: The purpose of this study was to explore emergency room nurse's work experiences during the COVID-19 pandemic. Methods: Data were collected from 15 registered nurses working in the emergency room between October, 10th and December 15th, 2020, through focus group interviews and in depth interviews. Collected data were analyzed using Colaizzi's phenomenological method. Results: The study derived four categories and eight themes. The four categories are 'sense of cringing with fear', 'nursing in chaotic situation', 'lonely struggles', and 'career growth as a nurse'. Emergency room nurses experienced fear and confusion in the COVID-19 pandemic, but overcame the crisis and had positive experiences of professional growth as a nurse. Conclusion: To protect emergency room nurses from infectious disease and improve their professional quality of life during the COVID-19 pandemic appropriate education and healthcare resource should be provided. It is necessary to reflect clinical worker's opinions and improve the delivery system of guideline to reduce confusion in the field and develop practical infectious disease control guideline. Furthermore, better working conditions, appropriate rewards and social and mental support should be provided for nurses in emergency room.

Similarities and Differences in Temperament Among Korean-Chinese, Chinese-Korean, Chinese and Korean Children (조선족, 화교, 한족 그리고 한국 아동의 기질에서의 유사점과 차이점에 관한 연구)

  • Park, Min-Jung;Park Choi, Hyewon
    • Korean Journal of Child Studies
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    • v.28 no.1
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    • pp.129-145
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    • 2007
  • The short form of the Early Adolescent Temperament Questionnaire-Revised(Ellis & Rothbart, 1999) was translated into Korean for Korean(N=367) and Korean-Chinese(N=258) children and into Chinese for Chinese-Korean(N=232) and Chinese(N=211) children. This 43 item scale of self-ratings was administered to 4th graders by home-room teachers in China and in Korea. Korean-Chinese children rated themselves higher on affiliation, depression, fear, pleasure- and perceptual - sensitivity and shyness than other groups. Chinese-Korean children were higher on affiliation, aggression and frustration, Chinese children were higher on activation control and Korean children rated themselves lowest on all subscales. Korean girls were higher than boys on activation control and affiliation. Korean boys were higher than girls on pleasure sensitivity. Chinese boys were higher than girls on aggression.

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Research on Asocial Behavior by Types of Internet Addiction in Elementary School Students (인터넷 중독에 따른 초등학생의 비사회 행동 연구)

  • Hong, Seung-Pyo;Lee, Hee-Joo
    • Korean Journal of Child Studies
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    • v.28 no.1
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    • pp.205-216
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    • 2007
  • An internet addiction measure(Park et al., 2001) and an asocial behavior measure(K. J. Lee, 1997) were administered to 232 6th-grade students. Statistical analyses were by mean-difference scores and t-test. Results showed that all aspects of internet addiction(preoccupation, compulsive use, relapse, tolerance/dependence and impediments in daily life) were related to both the inner asocial behaviors of depression, social withdrawal and over-anxiety and the external asocial behaviors of aggressiveness, delinquency and hyperactivity. The only exception was that tolerance/dependence was not related to delinquency. Boys addicted to the internet were more socially withdrawn, aggressive, delinquent and hyperactive than girls. From the results, it can be suggested that internet education should be carried out from the elementary educational level.

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Effects of Acanthopanax koreanum Extracts on Anticancer Related Cytokine Secretions (섬오가피 추출물의 항암관련 사이토카인 분비활성)

  • Lyu, Su-Yun;Park, Won-Bong
    • YAKHAK HOEJI
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    • v.54 no.4
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    • pp.232-239
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    • 2010
  • Stems and roots of Acanthopanax koreanum Nakai were extracted with water and treated on immune cells in order to determine their immunomodulatory activites. Various Th-1 type cytokines were measured using ELISA including interleukin (IL)-2, IL-12, interferon-gamma (IFN-$gamma$), and tumor necrosis factor-alpha (TNF-$\alpha$) secreted by dendritic cells, T-cells, intestinal epithelial cells, natural killer cells, and macrophages. As a result, there was a significant increase in IL-12 and IFN-$\gamma$, secretion, but there was no change in the secretion of TNF-$alpha$. Additionally T-cells slightly increased the secretion of IL-2, but there was a significant increase of IL-2 in intestinal epithelial cells. Therefore, our results suggest that A. koreanum Nakai may act as an immunomodulator by stimulating the cell-mediated immunity which can help the immune system defend against infections or cancer cells.

PRIMORDIAL RADIONUCLIDES DISTRIBUTION AND DOSE EVALUATION IN UDAGAMANDALAM REGION OF NILGIRIS IN INDIA

  • Manikandan, N.Muguntha;Selvasekarapandian, S.;Sivakumar, R.;Meenakshisundaram, V.;Raghunath, V.M.
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.183-190
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    • 2001
  • The activity concentration of primordial radionuclides i.e., $^{238}U$ series, $^{232}Th$ series and $^{40}K$, in soil samples collected from Udagamandalam environment, have been measured by employing NaI (Tl) Gamma ray Spectrometer. The absorbed gamma dose rate has also been simultaneously measured by using both Environmental Radiation Dosimeter at each soil sampling location (ambient gamma dose) as well as from the gamma dose derived from the activity concentration of the primordial radionuclides. The results of activity concentration of each radio nuclides in soil, absorbed dose rate in air due to soil activity and possible cosmic radiation at each location along with human effective dose equivalent for Udagamandalam environment are presented and discussed.

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