• Title/Summary/Keyword: sampling survey

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Parameter Estimation of Gravity Model by using Transit Smart Card Data (대중교통 카드를 이용한 중력모형 파라메타 추정)

  • Kim, Dae-Seong;Lim, Yong-Taek;Eom, Jin-Ki;Lee, Jun
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.1799-1810
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    • 2011
  • Origin-Destination(OD) trip survey being used in travel demand forecasting has been obtained through totalizing process with direct sample survey techniques such as plate license survey, roadside interview, household travel survey, and cordon line counts. However, the OD survey has many discrepancies in sampling, totalizing process, and such discrepancies contains problems of difference between forecasted traffic volume and observed data. On the other hand, transit smart card data recently collected has credible resource of obtaining travel information for bus and metro. This paper presents parameter estimation of gravity model by using transit smart card data. Through the parameter estimation method, we estimated =0.57, ${\beta}$=0.14 of gravity model for bus, and ${\alpha}$=-0.21, ${\beta}$=0.05 for metro. The statistical test such as T-test, coefficient of correlation, Theil`s inequality coefficient showed no difference between observed volume and estimated volume. Elasticities of bus and metro derived in this paper are also reasonable.

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Development of energy-harvesting based safety apparel for night workers (야간 작업자를 위한 에너지 하베스팅 기반 안전의복 개발)

  • Yoon, Jung-A;Oh, Yujin;Oh, Hwawon;Lee, Younhee
    • The Research Journal of the Costume Culture
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    • v.26 no.4
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    • pp.503-518
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    • 2018
  • The purpose of this study is to illustrate the design of safety suits based on energy-harvesting technology, particularly targeting street cleaners who must work at night with high mobility. The design focuses on applying lightweight energy-harvesting tools and illuminant into the wear. The design development reflects feedback from testers collected via survey constituting a key methodology. The development process has two main stages. Each stage uses a process of design prototyping, internal examination, test sampling, test wearing, and wearers' feedback via survey that consists of questions on visibility, wearing convenience, and washability. The first stage results show the design of safety suits with energy-harvested LED illuminant inserted and the survey results collected from street cleaners dressed in 4 sample and 80 actual suits in total. Improved based on the first-stage survey results, the second stage designs the suits with detachable energy-harvested EL tape. From these 5 sample and 30 actual second-stage suits, the additional survey indicates that this second-stage design facilitates more visibility and convenience in washing and wearing than the first-stage design. Accordingly, one can expect that this new design can apply not only to safety suits for night workers but also to handicapped or outdoor sportswear applications in the future.

Teachers' Perceived Dimensions on Elementary School Health Education Curriculum: An Experimental Trial Based on Concept Mapping Approach (초등학교 보건교육 교과영역에 대한 교사들의 인식도 속성: Concept mapping 기법을 활용한 실험적 시도)

  • Park, Kyoung-Ok
    • Korean Journal of Health Education and Promotion
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    • v.24 no.1
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    • pp.93-108
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    • 2007
  • Background: School is a primary health education setting for children and the continuous support should be provided to renew school health education curriculum correspondent to socio-cultural changes in Korean society. Objectives: This study was conducted to identify the principals' and teachers' needs of health education topics for their students and to analyze their conceptual map for health education curriculum in Korean elementary school. Methods: The sample size of the first survey was 179 and that of the second survey was 691 of elementary school principals and teachers from stratified sampling over Korea. The self-administered mailing survey was conducted to o identify the factor structure of the health education topics and to analyze the conceptual properties with exploratory factor analysis and multidimensional scaling analysis in SPSS 12.0. Results: A total of 21 health education topics were collected from the first survey and 31 topics were, comprehensively, generated for the second survey. The five factors were determined: 'life health promotion behavior,' 'drug control and mental health,' 'bulling and aggression prevention,' 'safety perception and injury prevention,' and 'sex education and sexual harassment.' The educational need scores were the highest in 'safety perception and injury prevention.' The two-dimensional cooperates were generated for the 31 health education topics and the two dimensional properties which divided the conceptual space were 'health-safety' for one and 'public/environmental-individual/personal' for the other. Conclusions: Health education curriculum and textbook should be developed considering teachers' needs and conditions for health education in school fields. The field-based health education programs or textbook would make more possible problem-solving health education for children in real school fields.

Cancer Registration in Basrah-Southern Iraq: Validation by Household Survey

  • Hussain, Riyadh Abdul-Ameer;Habib, Omran S
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup3
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    • pp.197-200
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    • 2016
  • On an international scale, the burden of cancer in absolute numbers continues to increase, mainly due to aging of population in many countries, the overall growth of the world population, changing lifestyle with increasing cancer-causing behavior, like cigarette smoking, changing dietary habits and sedentary life. Cancer is the second-leading cause of death and disability in the world, after only heart disease. Recently, increasing incidence and mortality of cancer have also become evident in the developing world. In Iraq and particularly in Basrah in the southern part of the country, the burden has definitely increased and deserves extensive research. The present paper is part of an extensive household survey carried out in Basrah in 2013. Among the objectives was to validate official cancer registration in the governorate. The cross-sectional survey had a retrospective component to inquire about the incidence of cancer and cancer-related deaths during the three years preceding the date of inquiry (2010-2012). A convenient sample of 6,999 households with 40,688 inhabitants using multistage cluster sampling was surveyed involving all urban and rural areas of Basrah. The official cancer registration activities in Basrah seemed to have attained a high level of registration coverage (70-80%) but the gap, represented by missed cases, is still high enough to criticize the system. Most of the missing cases were either not notified by treating facilities or they were diagnosed and treated outside Basrah. Using a set of parameters, the pattern of cancer was consistent based on data of the household survey and data of the cancer registry but a gap still existed in the coverage of incident cancer and mortality by cancer registration. Integrated serious steps are required to contain the risk of cancer and its burden on the patient through improving the registration process, improving early detection, diagnostic and management capabilities and encouraging scientific research to explore the hidden risk factors and possible causes of low registration coverage. Periodic household surveys seemed feasible and essential to support routine registration.

Comparison of Univariate Kriging Algorithms for GIS-based Thematic Mapping with Ground Survey Data (현장 조사 자료를 이용한 GIS 기반 주제도 작성을 위한 단변량 크리깅 기법의 비교)

  • Park, No-Wook
    • Korean Journal of Remote Sensing
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    • v.25 no.4
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    • pp.321-338
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    • 2009
  • The objective of this paper is to compare spatial prediction capabilities of univariate kriging algorithms for generating GIS-based thematic maps from ground survey data with asymmetric distributions. Four univariate kriging algorithms including traditional ordinary kriging, three non-linear transform-based kriging algorithms such as log-normal kriging, multi-Gaussian kriging and indicator kriging are applied for spatial interpolation of geochemical As and Pb elements. Cross validation based on a leave-one-out approach is applied and then prediction errors are computed. The impact of the sampling density of the ground survey data on the prediction errors are also investigated. Through the case study, indicator kriging showed the smallest prediction errors and superior prediction capabilities of very low and very high values. Other non-linear transform based kriging algorithms yielded better prediction capabilities than traditional ordinary kriging. Log-normal kriging which has been widely applied, however, produced biased estimation results (overall, overestimation). It is expected that such quantitative comparison results would be effectively used for the selection of an optimal kriging algorithm for spatial interpolation of ground survey data with asymmetric distributions.

Vertical distribution of giant jellyfish (Nemopilema nomurai) in the coastal waters of Korea and its correlation analysis by survey method (우리나라 연근해 해역에서 서식하는 노무라입깃해파리(Nemopilema nomurai)의 수층별 분포 및 조사방법별 상관성 분석)

  • OH, Sunyoung;KIM, Kyoung Yeon;LIM, Weol Ae;PARK, Geunchang;OH, Hyunjoo;OH, Wooseok;LEE, Kyounghoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.57 no.4
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    • pp.351-364
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    • 2021
  • In this study, the vertical distribution of giant jellyfish analyzed echo counting method and such survey methods as sighting and trawl were used to compare its density estimates. In May and July 2021, surveys were conducted in the East China Sea and the coastal waters of Korea. As a result, Nemopilema nomurai were evenly distributed in all water layers in East China Sea in May and July. When considered the correlation by each survey methods, it is possible to identify jellyfish in the surface area by sighting method and using sampling net; however, it has a low correlation with acoustic estimates due to marine environmental factor such as weather condition, wind and atmospheric pressure. Therefore, the result can be utilized by basic data when estimating jellyfish's distribution patterns and density estimates from each survey methods hereafter.

Assessing Disaster Response Capability and Feature Analysis for Coastal Residents of Korea using Sampling Process (표본추출법을 이용한 연안주민의 재해대응능력 평가 및 특성 분석)

  • Kang, Tae-Soon;Oh, Hyeong-Min;Kim, Jong-Kyu;Jeong, Kwang-Young;Hwang, Soon-mi;Kim, Soo-Min
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.20 no.1
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    • pp.55-61
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    • 2017
  • This study conducted a survey to evaluate the disaster response capability of coastal residents and analyzed the characteristics. For the sampling process, nonrandom sampling method was used. Sample size is 4,520 and sample error is ${\pm}1.5%p$ at 95% confidence level. As a result of the survey, 72% and 68% of the respondents said that they recognized the emergency contact network and listened to the disaster broadcast. On the other hand, 17% and 18% said that they organized the local voluntary disaster prevention teams and participated in disaster preparedness training. In addition, male's disaster response capability was higher than female's, and first aid techniques and participation in disaster preparedness training were higher in teens and twenties. By occupation, public official possess the highest response capability. By region, it was high in the East coast and low in the South coast. It is necessary that the authorities improve the national disaster preparedness training and publicity to enhance the coastal disaster response capability of coastal residents.

Health Behaviors among Adolescents in the Rural Area in Korea (농촌지역 청소년의 건강행태)

  • Park, Soon-Woo
    • Journal of agricultural medicine and community health
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    • v.34 no.2
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    • pp.202-213
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    • 2009
  • Objectives: The aim of this study was to compare health related behaviors among adolescents in the rural area with those in the urban area in Korea. Methods: The data source was the Korea Youth Risk Behavior Web-based Survey in 2005. With two stage cluster sampling, a total of 58,224 sample was selected from 799 middle and high schools nationwide. The area was classified into county area, small to medium city, and large city, and then the county area was considered as a rural area. Data was analyzed with STATA 9.0 using the method of complex survey data analysis considering sampling weight, strata, and primary sampling unit. Results: The prevalence of health related behaviors among adolescents in the rural area was higher than the city area as following health behaviors: smoking behaviors of smoking experience, smoking experience before entrance to middle school; drinking behaviors of frequent drinking, high risk behaviors with drinking; dietary behaviors of omitting of lunch or dinner, less intake of fruits or milk, more intake of cooky; oral hygiene of less tooth brushing, less preventive oral care, more oral symptoms and less dentist visit; safety behaviors of less wearing of safety belt or protective device; general hygiene of less hand washing before meal or after visiting rest room. Conclusions: The health behaviors among adolescents in the rural area were generally poorer than the city area. The results showed national health program for adolescents should be conducted primarily for those in rural areas. Further study is needed to explore the factors related with the discrepancy of health behaviors between the rural and urban area.

Propensity Adjustment Weighting of the Internet Survey by Volunteer Panel (자원자 패널에 의한 인터넷 조사의 성향조정 가중화)

  • Huh, Myung-Hoe;Cho, Sung-Kyum
    • Survey Research
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    • v.11 no.2
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    • pp.1-28
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    • 2010
  • This paper reports the results of the 2009 Internet volunteer panel version of the social survey conducted by Statistics Korea (Korea National Statistical Office). Authors identify socio-psychological characteristics of Internet survey volunteers and present quantitative evaluation of the propensity adjustment weighting method intended to remove Internet sample bias. The nine criteria used for propensity adjustment were regions, urban/rural, gender, age, education, consumer satisfaction, views on income distribution, newspaper access and Internet news access. Propensity adjustment weighting based on the logit model and rim weights were applied to the online survey of 2,903 respondents using the face-to-face area sample data of 37,049 respondents as reference. A total of 106 items were used for evaluating the propensity adjustment weighting methods. The results showed that in 80% of survey items the propensity adjustment weighting yielded better estimates compared to simple demographic weighting. This suggests that Internet surveys by volunteer panels are useful for conducting the general social study in Korea. The reference survey data for this study contains several items on social-psychological behaviors and attitudes, is large in size and obtained by probability sampling. Thus it may be utilized in propensity adjustment of other Internet surveys.

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The Trend of Food and Nutrient Intakes of Korean(1969-1989) -The First Report, Survey Methods in the Annual Report of the National Nutrition Survey- (한국인의 식품 및 영양섭취상태 추이(1969-1989) -제 1보, 국민영양조사보고서의 조사방법을 중심으로-)

  • Moon, Hyun-Kyung;Park, Mi-A;Kim, Eul-Sang;Song, In-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.5
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    • pp.502-508
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    • 1992
  • From 1969, when the National Nutrition Survey started, to 1989, survey methods are studied for each year. survey methods are examined about the area surveyed, the size and the contents of survey. The National Nutrition Survey are supervised by the Ministry of Health and Social Affairs (MOHSA). The department in charged are changed according to the reorganization of the ministry. Items of the physical examination in the contents of survey are decreased. Sampling methods are changed two times. Until 1974, area and household surveyed are smaller than 1,000 households. From 1989, the number of households surveyed are 2,000. The number of subject surveyed are changed at 1974, 1983 and 1988. From 1988, the number of subject surveyed are about 8,000. Seasons for the survey are summer before 1978 and fall after that. The result suggests that careful attention should be paid to analyzing results of survey because of variation in seasons.

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