• Title/Summary/Keyword: Complex Sample Design

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Study on Food-Intake and Atopic Dermatitis among Adolescents : Findings from the Korea Youth Risk Behavior Web-based Survey (청소년들의 아토피 피부염과 식품섭취빈도에 관한 연구 : 청소년건강행태온라인조사 자료를 중심으로)

  • Lee, Jee Hye
    • Journal of the Korean Dietetic Association
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    • v.22 no.2
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    • pp.79-87
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    • 2016
  • The aim of this study was to explore the relationship between demographic characteristics and atopic dermatitis, along with adolescents' body mass index. Also, this study explored the association between dietary intakes (fruits, soda, caffeinated beverages, instant food, cracker, vegetables, and milk) of adolescents and atopic dermatitis. Korea Youth Risk Behavior Web-based Survey for 2014 was used for data analysis, in which a total of 3,532,149 middle and high school students participated. Data were analyzed by descriptive analysis and logistic regression based on the complex sample design using SPSS ver.20.0 statistics. The results showed that males had a higher prevalence rate of atopic dermatitis than females. The significant association between body mass index and atopic dermatitis was found (F=46.625, P<0.001). Students who have higher levels of body mass index showed a higher prevalence rate of atopic dermatitis. Finally, the findings showed that the intake of vegetable and milk had associations with atopic dermatitis (F=6.795, P<0.001). Greater vegetable intake was associated with less atopic dermatitis whereas greater milk intake was associated with more atopic dermatitis prevalence. Based on the above results, we found that demographic characteristics, body mass index, and some dietary food intakes of adolescents had influences on prevalence rate of atopic dermatitis.

Factors related to Adolescents' Sexual Experience (청소년의 성경험 관련요인)

  • Boo, Yun Jeong;Kang, Moon Jung;Yi, Jee Seon
    • Journal of the Korean Society of School Health
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    • v.30 no.2
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    • pp.154-163
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    • 2017
  • Purpose: This study aimed to understand the current situation of Korean adolescents' sexual experience and its characteristics by school level, gender, and related factors to their sexual experience. This could be the basic evidence for the development of various sex education programs for the youth. Methods: This study used the 11th online survey data on youth health behavior (2015) and all 68,043 students who participated in the study were included for the analysis. The binominal logistic regression model was used to identify the characteristics and relevant factors of sexual intercourse experience. Analysis was performed by complex sample design using SPSS/WIN 18.0. The statistical significance was defined as p<.05 with a two-sided test. Results: The factors related to sexual experience of adolescents included grade, sadness and hopelessness, smoking, Internet addiction, and sex education in school, for middle school boys. For middle school girls, grade, residence area, sadness and hopelessness, smoking, drinking, and sex education in school were related. For high school boys, the factors were grade, living with parents, economic situation, sadness and hopelessness, smoking, drinking, and Internet addiction. For high school girls, grade, sadness and hopelessness, smoking, and drinking were found to be related factors. Conclusion: The results of this study suggest that a practical program considering adolescents' level and characteristics should be developed and applied.

Forces Prediction by Indirect Force Measurement and Pseudo-inverse Technique (간접 힘 측정 방법과 가상 역행렬을 이용한 힘 예측)

  • Ahn, Byoung-Ha;Shim, Jae-Sool
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.6
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    • pp.43-50
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    • 2002
  • In the design of structure, the forces acting on tai structure are key parameter fur noise and vibration control. However, in the complex structure, the forces at the injection point on the structure cannot be measured directly. So, it is necessary to find out Indirect force evaluation method. In this paper, forces have been measured with In-situ vibration responses and system information. And, three existing techniques of indirect force measurement, vita. direct inverse. principal component analysis and regularization have been compared. This paper shows that multi-vibration responses are essential for talc precise estimation of the forces. To check these conditions, rotary compressor is adopted as test sample, because it is very difficult to measure the injection forces from internal excitation to shell. It alas also been obtained that relatively higher force is transmitted through three welding paths to the compressor shell. It shows a good agreement between direct and indirect force evaluation with curvature shell and plate.

ADVANCED TEST REACTOR TESTING EXPERIENCE - PAST, PRESENT AND FUTURE

  • Marshall Frances M.
    • Nuclear Engineering and Technology
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    • v.38 no.5
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    • pp.411-416
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    • 2006
  • The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world's premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the comer 'lobes' to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 122 cm long and 12.7 cm diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors - US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, which places the capsule in direct contact with the primary coolant. The next level of experiment complexity is an instrumented lead experiment, which allows for active control of experiment conditions during the irradiation. The most complex experiment is the pressurized water loop, in which the test sample can be subjected to the exact environment of a pressurized water reactor. For future research, some ATR modifications and enhancements are currently planned. This paper provides more details on some of the ATR capabilities, key design features, experiments, and future plans.

A Review of the Trends of Journal Research on Dementia and Nursing Interventions for Demented Elders (치매와 치매노인 간호중재에 대한 연구 분석)

  • Roh, Kook-Hee
    • Research in Community and Public Health Nursing
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    • v.19 no.2
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    • pp.300-309
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    • 2008
  • Purpose: The purpose of this study was to review research trends and show the developmental direction of studies on dementia and nursing interventions for demented elders. Methods: This study analyzed 104 articles on dementia and 23 on nursing interventions for demented elders published until 2007. Results: These dementia studies increased in quantity after 1996, mainly in studies on demented elders and their families and in quantitative studies, Nursing intervention methods were music, light, horticultural therapy, reminiscence and complex therapeutic program, etc. There were experimental studies after 1996, but non-equivalent control group pretest-posttest design was 8(34.8%) of 23(100,0%). The medium sample size was 16.6 for experimental groups, 13 for control groups. The experimental time range was 10-120 minutes a day, frequency was 1-18 a week, and the total frequency was 4-72. The result variables were cognitive function, dementia behavior, emotion, depression, ADL, social behavior, etc. Conclusion: The findings of this review suggest that studies on dementia have been improved in quantity since 1996, but various and effective research methods should be developed as a way to further improve the quality of studies.

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Associations between Airborne Manganese and Blood Manganese in the Korean General Population according to KNHANES 2008-2009 (한국인의 혈중 망간농도와 공기중 망간농도의 관련성)

  • Jung, Kyung Sick;Lee, Jong Dae;Kim, Yong Bae
    • Journal of Environmental Science International
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    • v.22 no.12
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    • pp.1589-1598
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    • 2013
  • The objective of this study was to evaluate associations between airborne manganese and blood manganese in a general population of South Korean adults. The concentrations of airborne manganese in total suspended particulate (TSP) were calculated from data obtained from ambient air-monitoring stations (AAMSs) located in South Korea. Blood manganese data obtained Korean National Health and Nutrition Examination Survey (KNHANES) using a rolling sampling design involving a complex, stratified, multistage, probability cluster survey of a representative sample of the non-institutionalized civilian population of South Korea. Airborne manganese geometric means was 46.10 $ng/m^3$, blood manganese geometric means were 1.19 ${\mu}g/d{\ell}$ for male and 1.40 ${\mu}g/d{\ell}$ for female. In multiple linear regression analysis of log transformed blood manganeseas a continuous variable on airborne manganese, after adjusting for covariates including gender, age, job, smoking and drinking status, education level, BMI (body mass index). Airborne manganese was positively associated with blood manganese with statistical significance. The present study confirms that airborne manganese is a possible contributor to the increase of blood manganese in the adult general population.

A Study on the Relationship between Company Performance and Production Management in Apparel Manufacture

  • Lee, Sun-Hee;Suh, Mi-A
    • The International Journal of Costume Culture
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    • v.3 no.3
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    • pp.235-245
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    • 2000
  • The purposes of this study were 1) to investigate usage level of production strategies based on group of production environment, 2) to investigate usage level of production systems based on group of production strategy, and 3) to analyze each of company performance based on group of production strategy and system. For this study, the questionnaires were administered to 215 apparel manufactures in metropolitan area from Feb. to Mar. 1998. Employing a sample of 201, data were analyzed by factor analysis, descriptive statistics, cluster analysis, discriminant analysis, and multivariate analysis of variance. The following are the results of this study. 1. Concerning production strategy due to group of production environment, the stable group and the complicated group prefer to rice/quality centered strategy but the level of usage for strategies is so pretty that it is not significant to carry out them. 2. Concerning production system due to group of production strategy, the workers centered group is occupied high in the price/quality centered group & the complex group. And also the product centered system is occupied high in the flexibility centered group. 3. Concerning company performance due to group of production strategy and system, the price/quality centered group holds low position of performance comparing to another groups. And the performance of the managers centered group is higher than that of the workers.

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A Critical Review and Visim of Family Caregiving Research on the Demented Elderly간s in Republic of Korea (우리나라 치매노인 가족간호제공에 관한 연구의 현황과 전망)

  • 김진선
    • Journal of Korean Academy of Nursing
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    • v.29 no.6
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    • pp.1419-1433
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    • 1999
  • Little is known about the impact of family caregiving for the demented elderly in Korea. The purpose of this study was to identify the current state of development of family caregiving research for the demented elderly in Korea and to identify correlates of caregiver or health problems and burdens within the socio-political contexts of Korea. A critical review of 17 family caregivers was carried out. The review revealed that various caregiving impacts and correlates of caregiver burden or health problems have been studied in relation to demented elderly family caregiving. Family caregiving for the demented elderly is a very complex phenomenon and various factors were related to caregiver burden, or their emotional and physical health. Findings from studies reviewed have shown inconsistent, inconclusive, and contradictory results. Furthermore, several conceptual and methodological problems were identified in the studies reviewed: restricted conceptualization, unrepresentative study samples, inadequate sample size, inappropriate study design, absence of comparison groups, inappropriate psychometric properties, and uncontrolled confounding factors. More research, as well as directions for further research, is recommended to identify family caregiving the impact of for the demented elderly, and to clarify the factors that explain results.

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Identification of Feasible Scaled Teleoperation Region Based on Scaling Factors and Sampling Rates

  • Hwang, Dal-Yeon;Blake Hannaford;Park, Hyoukryeol
    • Journal of Mechanical Science and Technology
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    • v.15 no.1
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    • pp.1-9
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    • 2001
  • The recent spread of scaled telemanipulation into microsurgery and the nano-world increasingly requires the identification of the possible operation region as a main system specification. A teleoperation system is a complex cascaded system since the human operator, master, slave, and communication are involved bilaterally. Hence, a small time delay inside a master and slave system can be critical to the overall system stability even without communication time delay. In this paper we derive an upper bound of the scaling product of position and force by using Llewellyns unconditional stability. This bound can be used for checking the validity of the designed bilateral controller. Time delay from the sample and hold of computer control and its effects on stability of scaled teleoperation are modeled and simulated based on the transfer function of the teleoperation system. The feasible operation region in terms of position and force scaling decreases sharply as the sampling rate decreases and time delays inside the master and slave increase.

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Design of a GIS-Based Distribution System with Service Consideration (서비스수준을 고려한 GIS기반의 차량 운송시스템)

  • 황흥석;조규성
    • Korean Management Science Review
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    • v.18 no.2
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    • pp.125-134
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    • 2001
  • This paper is concerned with the development of a GIS-based distribution system with service consideration. The proposed model could be used for a wide range of logistics applications in planning, engineering and operational purpose for logistics system. This research addresses the formulation of those complex prob1ems of two-echelon logistics system to plan the incorporating supply center locations and distribution problems based on GIS. We propose an integrated logistics model for determining the optimal patterns of supply centers and inventory allocations (customers) with a three-step sequential approach. 1) First step, Developing GIS-distance model and stochastic set-covering program to determine Optimel pattern of supply center location. 2) Second step, Optimal sector-clustering to support customers. 3) Third step, Optimal vehicle rouse scheduling based on GIS, GIS-VRP In this research we developed GUI-tree program, the GIS-VRP provide the vehicle to users and freight information in real time. We applied a set of sample examples to this model and demonstrated samp1e results. It has been found that the proposed model is potentially efficient and useful in solving multi-depot problem through examples. However the proposed model can provide logistics decision makers to get the best supply schedule.

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