• Proceedings of the Korea Water Resources Association Conference
• /
• 2018.05a
• /
• pp.304-304
• /
• 2018

이변량 빈도해석은 일반적으로 고정지속기간 강우량에 대해 빈도해석하는 단변량 빈도해석에 비해 지속기간을 확률변수로 이용하여 강우량과 동시에 확률변수로 사용할 수 있다는 장점이 있다. 하지만 확률분포형의 차원이 증가하기 때문에 기존 단변량 빈도해석에서 요구되던 표본크기보다 더 많은 표본이 필요하다. 우리나라 강우관측소의 경우 오래된 관측소의 경우에도 기록년수가 60년을 넘지 않아 연최대계열로 확률표본을 작성할 경우 이변량 빈도해석을 수행하기에 부족할 수 있다. 따라서 본 연구에서는 Peaks Over Threshold (POT) 방법을 이용하여 적정 확률표본을 선택하는 연구를 진행하였다. 서울 기상청 지점의 강우자료로부터 최소무강우시간을 이용하여 모든 강우사상을 추출하였으며 각 강우사상의 강우량과 지속기간이 확률변수로 사용되었다. 기존에 알려진 POT 방법들과 Anderson-Darling 적합도 검정을 이용한 절단값 산정방법등을 적용하여 확률표본 개수의 변화에 따른 주변분포형의 적합도 검정과 이변량 확률모형의 적합성을 살펴보았다.

• Journal of Industrial Convergence
• /
• v.20 no.10
• /
• pp.197-207
• /
• 2022

The purpose of this study is to identify factors that affect the cost of rehabilitation services for people with congenital disabilities. The subjects of this study were 712 persons who had a disability from prenatal life from data of the 2020 National Survey of the Disabled Persons. 19-40 years, middle-class economic status, monthly family income level, use of vouchers, satisfaction with service institutions, autistic disability types significantly contributed to the cost of rehabilitation services. Among them use of vouchers had the greatest influence on the cost of rehabilitation services. Therefore, in order to reduce the cost of rehabilitation services for people with the congenital disabilities, it is suggested to improve the target of the voucher program and to establish a rehabilitation service support system for the entire life span.

• Journal of Digital Contents Society
• /
• v.16 no.1
• /
• pp.63-70
• /
• 2015

In this paper, we estimate the life cycle from acceleration life test about the hard disk of disk array of image storage of PACS. Webuil distribution was selected by the Anderson-Darling goodness-of-fit test with data of down time at $50^{\circ}C$ and $60^{\circ}C$. The equality test of shape parameter and scale parameter was conducted, so that the probability distribution estimated from data of down time at $50^{\circ}C$ and $60^{\circ}C$ was not statistically significant. The shape parameter was 1.0409, The characteristic life was 24603.5 hours at normal user condition($30^{\circ}C$) by the analysis of weibull-arrhenius modeling which included the acceleration factor of temperature, and The activation energy was 0.5011 eV through arrhenius modeling. The failure analysis of the failure samples of acceleration test and the samples of market return was conducted, so that the share percentage of failure mode was detail difference but the rank of share percentage was almost same. This study suggest the test procedure of acceleration test of hard disk drive in PACS using environment, and help the life estimation at manufacture and use.

• Journal of Convergence for Information Technology
• /
• v.10 no.11
• /
• pp.302-312
• /
• 2020

This study examined whether there is a difference in cost asymmetry between a corporate listed on KOSDAQ and a corporate listed on KOSPI, and whether there is a difference in cost asymmetry depending on the size of the listed corporate. In the previous study, cost asymmetry was examined only for listed corporate, but the difference in size between KOSDAQ-listed corporate and KOSPI-listed corporate was not examined. However, according to many studies, since the characteristics of corporate and firm risks are different between corporate listed on KOSPI and corporate listed on KOSDAQ, or even for listed corporate, such an impact may affect the decision-making of internal resource allocation. The analysis was conducted that there would be a difference in the impact. For this study, the results of analyzing the KOSPI and KOSDAQ markets from 2011 to 2019 using the cost behavior model of Anderson et al. (2003), There was a difference in cost behavior in the KOSPI and KOSDAQ markets. Overall, as in previous studies, Cost Stickiness was appeared. but in the case of the KOSPI market, Cost Stickiness was mitigated.It was found that corporate with large corporate size made the decision to dispose of idle resources more clearly when sales decreased. In addition, it was observed that the higher the foreign investor's ownership ratio, the KOSPI market, and the larger the corporate size, the more clearly the Stickiness of cost was mitigated. This study expands research on cost asymmetry and reveals that there is a difference between the KOSPI market and the KOSDAQ market, and between the size of the corporate, and has a differentiation from previous studies.

• Journal of Digital Contents Society
• /
• v.15 no.1
• /
• pp.19-27
• /
• 2014

In order to estimate the life of 2,5 inch HDD which is adopted by PC environment, make the test plan which reflect the failure mode of market, make the test model of accelerated life test which reflect the stress of temperature. after an analysis of the environment of PC using, test procedure was decided that operation was write 50 % and read 50 %, and then access method was sequential 50 % and random 50%. The acceleration life test was executed on condition that temperature was $50^{\circ}C$ and $60^{\circ}C$, performance was 95 % in max performance, test time was 1000 hours. by the test of goodness of fit of anderson-darling of the failure data during test, it was confirmed that the distribution of failure fellow weibull. test for shape and scale was equal, and shape parameter was 0.7177, characteristic life was 429434 hours at normal user condition($30^{\circ}C$) by the analysis of weibull-arrhenius modeling. It made no difference about the statistics when equality test was executed. The activation energy was 0.2775eV. In analyzing between the failure samples of acceleration test and the samples of market return even though there is detail difference about the share of failure mode, the rank of share was almost same. This study suggest the test procedure of acceleration test of 2.5 inch HDD in PC using environment, and help the life estimation at manufacture and user.

• Journal of Industrial Convergence
• /
• v.21 no.10
• /
• pp.167-180
• /
• 2023

The aim of this study is to explore the factors that influence the health care utilization of disabled workers who returned to their original workplace after an occupational accident. The study sample consisted of 457 workers who suffered from occupational accidents and were rated as disabled based on the data from the PSWCI in 2021. Data analysis was performed using a hierarchical multiple regression analysis with SPSS WIN 26.0. The study findings revealed that the number of outpatient visits was affected by factors such as daily wage payment, economic status, physical activity limitations, subjective health status, and chronic diseases. Moreover, health care expenditures were determined by factors such as having a caregiver for daily living, burn injuries, and physical activity limitations. Therefore, to increase the accessibility of health care utilization for disabled workers, the role of nurses in the workplace should be expanded, employers should include a health care utilization plan when developing a return-to-work plan, and research on the introduction of a paid sick leave system that allows workers to rest when they are sick is needed. It is also necessary to alleviate the economic burden by increasing the coverage of benefits for burn and rehabilitation treatments.

• The Korean Journal of Applied Statistics
• /
• v.20 no.2
• /
• pp.267-280
• /
• 2007

Various single-valued design optimality criteria such as D-, G-, and V-optimality are used often in constructing optimal experimental designs for mixture experiments in a constrained region R where lower and upper bound constraints are imposed on the ingredients proportions. Even though they are optimal in the strict sense of particular optimality criterion used, it is known that their performance is unsatisfactory with respect to the prediction capability over a constrained region. (Vining et at., 1993; Khuri et at., 1999) We assume the quadratic polynomial model as the mixture response surface model and are interested in finding efficient designs in the constrained design space for a mixture. In this paper, we make an expanded list of candidate design points by adding interior points to the extreme vertices, edge midpoints, constrained face centroids and the overall centroid. Then, we want to propose a robust design with respect to D-optimality, G-optimality, V-optimality and distance-based U-optimality. Comparing scaled prediction variance quantile plots (SPVQP) of robust designs with that of recommended designs in Khuri et al. (1999) and Vining et al. (1993) in the well-known examples of a four-component fertilizer experiment as well as McLean and Anderson's Railroad Flare Experiment, robust designs turned out to be superior to those recommended designs.

• Journal of Digital Convergence
• /
• v.18 no.4
• /
• pp.177-191
• /
• 2020

This study examines the effect of the self-overviewing attributes derived from agency problem on the cost behavior in franchise industry. To solve the research problem, we developed the proxies for self-overviewing attributes of domestic franchise CEO and used Anderson et al. (2003)'s cost behavior model to test hypothesis. Moreover, we grouped the self-overviewing variables for additional test. We find that operating costs are more sticky for firms which present higher CEO's self-overviewing attributes in franchise industry. Second, we find that the greater the self-overviewing tendency, more strengthened cost stickiness when sales decrease. This study is meaningful in that we developed proxies for self-overviewing propensity, such as the hypodermic behaviors of franchise CEO, which have not been performed in previous studies, to enhance future studies of franchise CEO. Futhermore, we empirically provide the effects of CEO's self-overviewing attributes on the operating costs behaviors, suggesting useful information to franchise stakeholders such as prospective start-ups, franchisee and investors.

• The Journal of Korean Society for Radiation Therapy
• /
• v.28 no.1
• /
• pp.57-64
• /
• 2016

Purpose : To evaluate the results of absorbed and effective doses using CBCT and 4D-CBCT settings for lung cancer. Materials and Methods : This experimental study. Measurements were performed using a Anderson rando phantom with OSLD(optically stimulated luminescent dosimeters). It was performed computed tomography(Lightspeed GE, USA) in order to express the major organs of the human body. Measurements were obtained a mean value is repeated three times each. Evaluations of effective dose and absorbed dose were performed the CL-IX-Thorax mode and Truebeam-Thorax mode CBCT. Additionally, compared Truebeam-Thorax mode CBCT with Truebeam-Thorax mode 4D-CBCT(Four-dimensional Cone Beam Computed Tomography) Results : Average absorbed dose in the CBCT of CL-IX was measured in lung 2.505cGy, heart 2.595cGy, liver 2.145cGy, stomach 1.934cGy, skin 2.233cGy, in case of Truebeam, It was measured lung 1.725cGy, heart 2.034cGy, liver 1.616cGy, stomach 1.470cGy, skin 1.445cGy. In case of 4D-CBCT, It was measured lung 3.849cGy, heart 4.578cGy, liver 3.497cGy, stomach 3.179cGy, skin 3.319cGy Average effective dose, considered tissue weighting and radiation weighting, in the CBCT of CL-IX was measured lung 2.164mSv, heart 2.241mSVv, liver 0.136mSv, stomach 1.668mSv, skin 0.009mSv, in case of Turebeam, it was measured lung 1.725mSv, heart 1.757mSv, liver 0.102mSv, stomach 1.270mSv, skin 0.005mSv, In case of 4D-CBCT, It was measured lung 3.326mSv, heart 3.952mSv, liver 0.223mSv, stomach 2.747mSv, skin 0.013mSv Conclusion : As a result, absorbed dose and effective Dose in the CL-IX than Truebeam was higher about 1.3 times and in the 4D-CBCT Truebeam than CBCT of Truebeam was higher about 2.2times However, a large movement of the patient and respiratory gated radiotherapy may be more accurate treatment in 4D-CBCT. Therefore, it will be appropriate to selectively used.

• Journal of Preventive Medicine and Public Health
• /
• v.26 no.4 s.44
• /
• pp.599-613
• /
• 1993

To study the pattern of prenatal care utilization and its determinants in rural Korea, 976 mothers (65.5%) out of 1,489 living mothers in Chinyang, Sachon and Hapchon Counties in Kyongsangnam Province who had delivered a baby between July 1, 1990 and June 30, 1991 were interviewed by the Myon health workers from January 3 through February 15, 1992. The Anderson's behavioral model for health service utilization was applied to develop the frames for analysis. The dependent variable was a number of prenatal care visits. And the independent variables included In the model were the variables pertaining to the predisposing, enabling, medical need and other components. The proportion of mother who had ever received the prenatal care service for the index pregnancy was 97.3%. However, the proportion of mothers who had made more than 10 visits was only 20.6%, which indicated that majority of mothers had paid far less visits than recommended $10{\sim}12$ visits for each normal pregnancy. The low utilization of prenatal care services (none or less than 4 visits) was related to mother's low educational level, the high birth order, beneficiary of the medical aid, the absence of clinic in the community, no diagnosed disease of mother during pregnancy, and mothers engaged in farming. Inequity of access seemed to exist because social structure variables and the variables of enabling component were important predictors. And there seemed to be high mutability in equalizing the distribution of prenatal care services because the variables of enabling component such as type of medical security and whether there was a clinic or not in the community were substantially important.