• 제목/요약/키워드: Population-based

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An Overview of Bootstrapping Method Applicable to Survey Researches in Rehabilitation Science

  • Choi, Bong-sam
    • 한국전문물리치료학회지
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    • 제23권2호
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    • pp.93-99
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    • 2016
  • Background: Parametric statistical procedures are typically conducted under the condition in which a sample distribution is statistically identical with its population. In reality, investigators use inferential statistics to estimate parameters based on the sample drawn because population distributions are unknown. The uncertainty of limited data from the sample such as lack of sample size may be a challenge in most rehabilitation studies. Objects: The purpose of this study is to review the bootstrapping method to overcome shortcomings of limited sample size in rehabilitation studies. Methods: Articles were reviewed. Results: Bootstrapping method is a statistical procedure that permits the iterative re-sampling with replacement from a sample when the population distribution is unknown. This statistical procedure is to enhance the representativeness of the population being studied and to determine estimates of the parameters when sample size are too limited to generalize the study outcome to target population. The bootstrapping method would overcome limitations such as type II error resulting from small sample sizes. An application on a typical data of a study represented how to deal with challenges of estimating a parameter from small sample size and enhance the uncertainty with optimal confidence intervals and levels. Conclusion: Bootstrapping method may be an effective statistical procedure reducing the standard error of population parameters under the condition requiring both acceptable confidence intervals and confidence level (i.e., p=.05).

국내외 공공도서관 개관시간 기준 연구 (A Study on the Standards for Public Library Opening Hours in Foreign Countries and Korea)

  • 윤희윤
    • 한국도서관정보학회지
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    • 제44권1호
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    • pp.49-71
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    • 2013
  • 도서관은 지역주민이 장서 및 서비스를 가장 효과적이고 편리하게 이용할 수 있는 시간에 개관해야 한다. 달리 말해서 모든 공공도서관은 지역주민에게 적절한 개관시간을 제공해야 한다. 이에 본 연구는 국제기구(IFLA/UNESCO)와 주요 국가(미국, 캐나다, 영국, 프랑스, 호주, 중국과 대만, 일본, 한국)의 공공도서관기준을 대상으로 최소 개관시간을 분석하고 봉사대상인구에 기초하여 국내 공공도서관 자료실의 바람직한 주당 최소 개관시간 기준(1만명 미만은 45시간, 1만명~2만명 미만은 50시간, 2만명~5만명 미만은 55시간, 5만명~10만명 미만은 60시간, 10만명~30만명 미만은 65시간, 30만명 이상은 70시간)을 제안하였다.

Genetic Distances of Paralichthys olivaceus Populations Investigated by PCR

  • Yoon, Jong-Man
    • 한국발생생물학회지:발생과생식
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    • 제22권3호
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    • pp.283-288
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    • 2018
  • The author carried out PCR-based genetic platform to investigate the hierarchical polar dendrogram of Euclidean genetic distances of one bastard halibut population, particularly for Paralichthys olivaceus, which was further connected with those of the other fish population, by involving with the precisely designed oligonucleotide primer sets. Eight oligonucleotides primers were used generating excessively alterating fragments, ranging in size of DNA bands from larger than approximately 100 bp to less than 2,000 bp. As regards average bandsharing value (BS) results, individuals from Hampyeong population (0.810) displayed lower bandsharing values than did individuals from Wando population (0.877). The genetic distance between individuals approved the existence of close relationship in the cluster II. Relatively, individuals of one bastard halibut population were fairly related to that of the other fish population, as shown in the polar hierarchical dendrogram of Euclidean genetic distances. The points of a noteworthy genetic distance between two P. olivaceus populations demonstrated this PCR procedure is one of the quite a few means for individuals and/or populations biological DNA investigates, for species security and proliferation of bastard halibut individuals in coastal region of the Korea.

설악산 국립공원의 산양 보호구역 설정기법에 관한 연구: 서식지 적합성 모형, 서식지 수용능력, 최소 존속 개체군 이론을 이용하여 (Establishing a Korean Goral (Nemorhaedus caudatus raddeanus Heude) Reserve in Soraksan National Park, Korea: Based on Habitat Suitability Model, Habitat Capability Model, and the Concept of Minimum Viable Population)

  • 최태영;박종화
    • 한국조경학회지
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    • 제32권6호
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    • pp.23-35
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    • 2005
  • Korean goral (Nemorhaedus caudatus raddeanus) is an endangered species in Korea, and the rugged terrain of the Sorksan National Park $(373km^2)$ is a critical habitat for the species. Since the goral population is threatened by habitat fragmentation, it is essential to establish a reserve for the isolated goral population. The objective of this study was to propose a reserve for Korean goral in the national Park We employed habitat suitability model, habitat capability model, and the concept of minimum viable population. The results of the study were as follows. First, the carrying capacity and optimal density of gorals in the national park were projected to be 449 gorals, and 251 gorals, respectively Second, since only one patch was projected to satisfy the criteria of minimum viable population (50 individuals/during 50 years), the long term extinction possibility of gorals in the site would be very high. Finally, the patch that satisfy the minimum viable population of goral was proposed as the core zone of the goral reserve and adjacent patches were included as buffer zones.

Probability Sampling Method for a Hidden Population Using Respondent-Driven Sampling: Simulation for Cancer Survivors

  • Jung, Minsoo
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권11호
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    • pp.4677-4683
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    • 2015
  • When there is no sampling frame within a certain group or the group is concerned that making its population public would bring social stigma, we say the population is hidden. It is difficult to approach this kind of population survey-methodologically because the response rate is low and its members are not quite honest with their responses when probability sampling is used. The only alternative known to address the problems caused by previous methods such as snowball sampling is respondent-driven sampling (RDS), which was developed by Heckathorn and his colleagues. RDS is based on a Markov chain, and uses the social network information of the respondent. This characteristic allows for probability sampling when we survey a hidden population. We verified through computer simulation whether RDS can be used on a hidden population of cancer survivors. According to the simulation results of this thesis, the chain-referral sampling of RDS tends to minimize as the sample gets bigger, and it becomes stabilized as the wave progresses. Therefore, it shows that the final sample information can be completely independent from the initial seeds if a certain level of sample size is secured even if the initial seeds were selected through convenient sampling. Thus, RDS can be considered as an alternative which can improve upon both key informant sampling and ethnographic surveys, and it needs to be utilized for various cases domestically as well.

Survey of Status for Ageing Population, Charge Organizations and Polices in UK

  • Kee, Dohyung
    • 대한인간공학회지
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    • 제33권5호
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    • pp.387-394
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    • 2014
  • Objective: The purpose of this study is to survey trend and the real state of ageing population in UK, and its charge organizations, relevant policies and studies. Background: As in other countries, UK population is ageing and people aged 65 or over account for about 17% of population in UK. Considering this ageing population, there are varying basic studies and policies for older people in UK. Method: First, the author consulted ageing and its policies in UK with some faculties in an UK university. Next, based on the results of consultation, wide literature survey was conducted, which includes papers in relevant academic journals, publications and website surfing. Results: A number of basic studies for surveying status and characteristics of older people as well as simple population trend for them have been conducted in UK. Healthcare services are free for all UK residents, and varying social care services including equipment, home and residential cares, financial support, etc., are provided by local governments. Cost of social cares is means-tested and is not free for everyone. There are a number of governmental or non-profit organizations dedicated to help older people access social care services or to financially fund research projects older people. Conclusion: There are more basic studies, and healthcare and social care services for older people in UK, compared to Korea. Application: It would be useful as basic data for establishing effective polices for old people in Korea.

농촌 생활서비스 시설 분포와 인구감소지역의 비교분석 (Comparative Analysis of Spatial Distribution of Rural Living Service Facilities and Depopulation Areas)

  • 최진아;김상범;김수연;조한솔
    • 한국농촌건축학회논문집
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    • 제24권4호
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    • pp.77-84
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    • 2022
  • The purpose of this study is to derive implications by comparing the spatial distribution of each service facility per unit population(1,000 people) with population decline areas. For this purpose, major concepts such as living infrastructure services, Spatial Distribution of Rural Living Service Facilities, areas of declining population, and regional extinction were reviewed and trends in prior research. Based on the literature review, 'Spatial Distribution of Rural Living Service Facilities' analysis criteria were set, and it was derived by 'the number of facilities per 1,000 population by township' using population data and rural space data. And the trend of each service sector was identified and implications were derived with 89 cities and counties in 'depopulation areas' suggested by the Ministry of Public Administration and Security. The derived implications are as follows. In the medical, leisure, and sports infrastructure sectors, 'rural areas with few service facilities per unit population' and 'depopulated areas' tended to coincide. In addition, the distribution characteristics of rural and urban areas differed by sector, which is judged to depend on the inclusion of rural facilities and population density.

Analysis of the Genetic Diversity and Population Structure of Amaranth Accessions from South America Using 14 SSR Markers

  • Oo, Win Htet;Park, Yong-Jin
    • 한국작물학회지
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    • 제58권4호
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    • pp.336-346
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    • 2013
  • Amaranth (Amaranthus sp. L.) is an important group of plants that includes grain, vegetable, and ornamental types. Centers of diversity for Amaranths are Central and South America, India, and South East Asia, with secondary centers of diversity in West and East Africa. The present study was performed to determine the genetic diversity and population structure of 75 amaranth accessions: 65 from South America and 10 from South Asia as controls using 14 SSR markers. Ninety-nine alleles were detected at an average of seven alleles per SSR locus. Model-based structure analysis revealed the presence of two subpopulations and 3 admixtures, which was consistent with clustering based on the genetic distance. The average major allele frequency and polymorphic information content (PIC) were 0.42 and 0.39, respectively. According to the model-based structure analysis based on genetic distance, 75 accessions (96%) were classified into two clusters, and only three accessions (4%) were admixtures. Cluster 1 had a higher allele number and PIC values than Cluster 2. Model-based structure analysis revealed the presence of two subpopulations and three admixtures in the 75 accessions. The results of this study provide effective information for future germplasm conservation and improvement programs in Amaranthus.

Yonsei Evolutionary Population Synthesis (YEPS) Model -III. Spectrophotometric Evolutions of Simple Stellar Population Models based on Empirical Spectra

  • Chung, Chul;Yoon, Suk-Jin;Lee, Young-Wook
    • 천문학회보
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    • 제38권2호
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    • pp.38.1-38.1
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    • 2013
  • We present the Yonsei evolutionary population synthesis (YEPS) models based on the high-resolution empirical spectral energy distributions (SEDs). We have adopted the MILES library in the optical wavelength, and our new models based on the MILES library show good agreements with our previous models presented in the YEPS I. The effect of hot horizontal-branch (HB) stars on the integrated properties of simple stellar populations (SSPs) is again confirmed by our models based on empirical SEDs. In addition, we have extended our empirical models to the near-IR wavelength and predicted the strengths of the calcium II triplet (CaT) and the Paschen triplet (PaT) based on the INDO-US and the Cenarro library. We find that the effect of HB stars and the age of SSPs on the CaT is almost negligible. On the other hands, the PaT models are very sensitive to the existence of hot stars, e.g., HB stars and young turn-off stars, and show very similar results with Balmer lines. Interestingly, the CaT distribution of GCs in NGC 1407, which is at odds with the optical (B-I) color distribution, can be explained by the unique feature of the CaT-[Fe/H] relations that show almost the same equivalent widths in the metal-rich regime. We will also discuss the impact of the second-generation populations on the strength of the CaT.

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GPU-based Stereo Matching Algorithm with the Strategy of Population-based Incremental Learning

  • Nie, Dong-Hu;Han, Kyu-Phil;Lee, Heng-Suk
    • Journal of Information Processing Systems
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    • 제5권2호
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    • pp.105-116
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    • 2009
  • To solve the general problems surrounding the application of genetic algorithms in stereo matching, two measures are proposed. Firstly, the strategy of simplified population-based incremental learning (PBIL) is adopted to reduce the problems with memory consumption and search inefficiency, and a scheme for controlling the distance of neighbors for disparity smoothness is inserted to obtain a wide-area consistency of disparities. In addition, an alternative version of the proposed algorithm, without the use of a probability vector, is also presented for simpler set-ups. Secondly, programmable graphics-hardware (GPU) consists of multiple multi-processors and has a powerful parallelism which can perform operations in parallel at low cost. Therefore, in order to decrease the running time further, a model of the proposed algorithm, which can be run on programmable graphics-hardware (GPU), is presented for the first time. The algorithms are implemented on the CPU as well as on the GPU and are evaluated by experiments. The experimental results show that the proposed algorithm offers better performance than traditional BMA methods with a deliberate relaxation and its modified version in terms of both running speed and stability. The comparison of computation times for the algorithm both on the GPU and the CPU shows that the former has more speed-up than the latter, the bigger the image size is.