• Journal of the Korean Data and Information Science Society
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• v.28 no.1
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• pp.11-20
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• 2017

In this paper, we introduced linear spatial time series (space-time autoregressive and moving average model) and nonlinear spatial time series (space-time bilinear model). Also we estimated the parameters by Kalman Filter method and made comparative studies of power of forecast in the final model. We proposed several weight matrices such as equal proportion allocation, reciprocal proportion between distances, and proportion of population sizes. For applications, we collected Mumps data at Korea Center for Disease Control and Prevention from January 2001 until August 2008. We compared three approaches of weight matrices using the Mumps data. Finally, we also decided the most effective model based on sum of square forecast error.

• Journal of Gastric Cancer
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• v.19 no.1
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• pp.92-101
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• 2019

Purpose: The aim of this study was to evaluate the trend of non-compliance with treatment (NCT) among gastric cancer patients in the Korean population. Materials and Methods: Using data from the Korea Central Cancer Registry from 1999 to 2015, patients who did not receive any treatment for gastric cancer within 4 months after diagnosis were defined as the NCT group. The annual incidence rate, distributions according to age group and stage, and 5-year relative survival of the patients exhibiting NCT were analyzed. Results: The number of NCT patients was 5,871 (30.6%) in 1999 and continuously decreased to 4,434 (15.3%) in 2015. Between 2006 and 2015, the proportions of NCT patients decreased from 72.9% to 55.0% among those 80 years old or older and from 9.2% to 5.4% among patients younger than 40 years. In patients with distant metastases, this proportion decreased from 35.5% to 32.7%, and this proportion also decreased from 17.6% to 8.2% among those with localized disease. The 5-year relative survival rates of NCT patients between 2011 and 2015 were significantly lower than those of the treated patients in each stage (60.2% vs. 99.7%, 13.8% vs. 67.1%, and 2.0% vs. 8.3% among those with localized, regional, and distant disease, respectively). Conclusions: The proportion of NCT gastric cancer patients has decreased during the last 16 years. However, considerable numbers of elderly patients are still NCT. There must be a strategy to decrease NCT and improve the nationwide survival rate of patients with gastric cancer.

• Journal of Environmental Health Sciences
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• v.48 no.2
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• pp.123-129
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• 2022

Background: The Environmental Health Action Program was a national project carried out from 2012~2021. It was aimed at developing public technologies to protect people's health from various environmental hazards. Objectives: One of the final goals of the project was "creating health benefits worth more than 179.2 billion won by reducing the environmental burden of disease." This study aims to evaluate whether the program sufficiently achieved the planned benefits. Methods: In order to secure consistency in evaluation, we applied the same equation used in the goal-setting process. It is comprised of six parameters to estimate the benefit: 1. The amount of medical expenses for environmental diseases; 2. The attributable proportion of environmental risk factors' 3. The rate of reduction in medical expenses for environmental diseases; 4. R&D project contribution; 5. The proportion of successful policy reflection; and 6. The contributions of the project. The corresponding variables were estimated at the end of the project, and the health benefits of the project were recalculated using the newly estimated variables. Results: It was estimated that a total of 195 billion won in health benefits occurred or will occur from 2015 to 2026. The main contributors for achieving the target were an increase in medical expenses for environmental diseases, a high score in the R&D project contribution, and the proportion of successful policy reflection. Conclusions: Technically, the equation used in the project is about medical expenses for environmental diseases rather than about the environmental burden of disease. There are several benefits of using the environmental burden of disease in the evaluation of public health policies. In further studies, developing a policy evaluation framework using indicators such as population attributable fraction would be needed.

• Journal of the Korean Geographical Society
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• v.49 no.3
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• pp.390-404
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• 2014

This study analysed the job-housing balance using the number of employees and workers data, and investigated the relationship between job-housing ratio and commuting trip in the Seoul metropolitan area. Between 2005-2010, in the central business district which functioned as urban center, the number of employees were reduced and population growth slowed. Meanwhile, the suburbanization of employment and population has advanced as the employment and population moved from Seoul to Gyeonggi-do. As the increasement of workers compared to the employees became prominent, the excess workers increased significantly. The size of excess workers acted as a factor which reduced the job-housing ratio. Job-housing imbalance worsened in Gyeonggi-do especially. While in many regions, job-housing imbalance improved in clerical, sales, and professional job sectors, but in some regions, the job-housing imbalance worsened in simple labor job and service job sectors. The number of jobs which job-housing imbalance was eased increased in the employment center. The more the job-housing ratio is high, the lower the degree of self-sufficiency of commuting trip and the proportion of internal commuters. In business centers where the number of employees exceed the number of workers, the job-housing ratio and the proportion of commuting trips coming from other regions showed decreasing trend together. The results bear important implications for regional labour market plans considering the spatial mismatch between jobs and housing.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6285-6288
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• 2015

Background: Breast cancer is commonly diagnosed at late stages in countries with limited resources. In Morocco, breast cancer is ranked the first female cancer (36.1%) and screening methods could reduce the proportion presenting with a late diagnosis. Morocco is currently adopting a breast cancer screening program based on clinical examination at primary health facilities, diagnosis at secondary level and treatment at tertiary level. So far, there is no systematic information on the performance of the screening program for breast cancer in Morocco. The aim of this study was to analyze early performance indicators. Materials and Methods: A retrospective evaluative study conducted in Temara city. The target population was the entire female population aged between 45-70 years. The study was based on process and performance indicators collected at the individual level from the various health structures in Tamara between 2009 and 2011. Results: A total of 2,350 women participated in the screening program; the participation rate was 35.7%. Of these, 76.8% (1,806) were married and 5.2% (106) of this group had a family history of breast cancer. Of the women who attended screening, 9.3% (190) were found to have an abnormal physical examination findings. A total of 260 (12.7%) were referred for a specialist consultation. The positive predictive value of clinical breast examination versus mammography was 23.0%. Forty four (35.5%) of the lesions found on the mammograms were classified as BI-RADs 3; 4 or 5 category. Cancer was found in 4 (1.95%) of the total number of screened women and benign cases represented 0.58%. Conclusions: These first results of the programme are very encouraging, but there is a need to closely monitor performance and to improve programme procedures with the aim of increasing both the participation rate and the proportion of women eligible to attend screening.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.2
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• pp.117-121
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• 1990

A sweet corn hybrid, Golden Cross Bantam 70, was grown at 5 plant populations (5,000, 6,000, 7,000, 8,000, and 9,000 plants/10a) under the transparent P .E. film mulch to find the best yield evaluation method. Plant population did not affect early plant growth, culm length, ear height, and silking date. However, number of tillers at harvest decreased but leaf area index increased with increased plant population. Marketable ears were divided into two classes; the first grade of which husked ear weight over l50g (unhusked ear weight 230g) and the second grade of which husked ear weight between 100 and 150g (unhusked ear weight between 180 and 230g) according to the whole sale market price. Average length, thickness, and weight of marketable ears over 100g of husked ears decreased with increased plant population. The proportion of ears over 150g decreased with increased plant population. However, total number and weight of marketable ears and gross income per 10a calculated considering weight and number of ears increased with plant population. There were highly positive correlations between gross income and ear number or ear weight per unit area. At high plant populations the number of marketable ears was overestimated but ear weight underestimated compared with gross income. Dry matter yield of stover increased with increased plant population and ranged 755-944kg/10a with 20.7-24.5% dry matter content. Rice black-streaked dwarf virus infection rate was 10.6-14.9%, but it was not related to plant population.

• Journal of Life Science
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• v.24 no.6
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• pp.612-617
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• 2014

The phenetic relationships among six natural populations of Equisetum pratense in Korea were investigated at the population level by constructing a tree based on Random Amplified Polymorphic DNA (RAPD) markers. RAPD analysis was also conducted to estimate genetic diversity and the population structure of E. pratense. A mean of 26.7% at the six population levels indicated polymorphism. E. pratense was found to have fewer alleles per locus (1.267) and fewer effective alleles per locus (1.176). Genetic diversity (0.102) in E. pratense is lower than the average for species with similar life history traits. Total genetic diversity values (HT) varied between 0.112 (OPD-07) and 0.445 (OPD-16), for an average overall polymorphic locus of 0.141. Inter-locus variation in the within-population genetic diversity ($H_S$) was low (0.102). Asexual reproduction, small population size, and the colonization process are proposed as possible factors contributing to the observed low genetic diversity in E. pratense. On a per-locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.129 for OPD-07 to 0.455 for OPD-09, with a mean of 0.277. This indicated that about 27.7% of the total variation was among populations. Thus, genetic variation (72.3%) resided within populations. This study contributes new information for research on the taxonomy and population genetics of E. pratense.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.227-230
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• 2000

A total of 90 isolates of Fusarium oxysporum f.sp. melonis, the causal agent of oriental melon (Cucumis melo var. makuwa) wilt, was isolated from symptomatic tissues of oriental melon from 4 provinces in Korea. These isolates were grouped into vegetative compatibility groups (VCGs) by demonstrating heterokaryosis through complementation using nitrate nonutilizing (nit) mutants. No self-incompatibility was observed in any of isolates. All isolates were grouped into 3 VCGs ; A, B, and C. iSOLATES BELONGING TO VCG A and VCG B accounted for 87% and 91% of the fungal population collected in 1991 and 1993, respectively. As the increment of cultivation period in the same field, the proportion of isolates belonging to VCG B increased whereas that of isolates belonging to VCG A decreased. Mean virulence of a total population increased as the increment of cultivation period in the same field. Isolates belonging to VCG B showed the highest increment of virulence. These data suggest that replanting of a host plant in the same field may cause increase of virulence in the pathogens. Furthermore, virulence of F. oxysporum f.sp. melonis isolates is related to the VCGs.

• The Korean Journal of Applied Statistics
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• v.28 no.6
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• pp.1113-1120
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• 2015

We propose a multi-proportions randomized response model by stratified simple random sampling for surveys of sensitive issues of a polychotomous population composed of several stratum. We also systemize a theoretical validity to apply multi-proportions randomized response model (Abul-Ela et al.' model, Eriksson's model) to stratified simple random sampling and derive the estimate and its dispersion matrix of the proportion of sensitive characteristic of population using the suggested model. Two types of sample allocations (proportional allocation and optimum allocation) are considered under the fixed cost. In efficiency, the Eriksson's model by stratified sampling are compared to the Abul-Ela et al.' model.

• Journal of the Korean Regional Science Association
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• v.6 no.2
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• pp.107-121
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• 1990

The structural change of occupational composition with the coming of post-industrial society is most evidently observed in the developed country. Specially representative of social changes is the emergence of new occupational sectors, such as the so-called quaternary and quinary sectors, which are based on the use of information technology and managerial skills. The paper raises the question of how and in what this chage of occupational components in a mtro area affects the existing residential structure over the period. In order to extend the discussion of the question, the related hypothetical statements on urban spatial impact due to transformation of the society have xtnsively considered and identified a possible multicenter structure concentration and deconcentration of new jobs and population over the metro area. For further examination, the renowned high tech city of Minneaplis -St. Paul has been selected and the occupational labour forces data for 1960 and 1980 analyzed. As a whole, this area has experienced a dispersal and reconcentration of population in new patterns which have resulted from changes in the occupational structure. In particular, the residential area of white-coller workers(the quaternary / quinary or information workers) has expanded into the city from a suburban core area. In this process, a large proportion of the manual-worker's residential areas in the central city either disappeared or diminished. Consequently, other isolated centers created by the manualworker residents are emerging in both the central city and suburbs. Thus, the development of mulitple centers or cores based on the distribution of occupational characteristics can be considered as a typical ongoing pattern of metro areas in the Unite States.