• Communications for Statistical Applications and Methods
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• v.15 no.6
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• pp.925-937
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• 2008

In this study, we considered the clustering analysis for stock return traded in the stock market. Most of financial time-series data, for instance, stock price and exchange rate have conditional heterogeneous variability depending on time, and, hence, are not properly applied to the autoregressive moving-average(ARMA) model with assumption of constant variance. Moreover, the variability is font and center for stock investors as well as academic researchers. So, this paper focuses on the generalized autoregressive conditional heteroscedastic(GARCH) model which is known as a solution for capturing the conditional variance(or volatility). We define the metrics for similarity of unconditional volatility and for homogeneity of model structure, and, then, evaluate the performances of the metrics. In real application, we do clustering analysis in terms of volatility and structure with stock return of the 11 Korean companies measured for the latest three years.

• Journal of the Korean Society of Food Culture
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• v.12 no.1
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• pp.87-96
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• 1997

The purpose of this study is, to examine current foodservice management practices at free meal service organization for elderly people and, to evaluate the attitude of recipients about the service and their ecological background. 6 meal service center as well as randomly selected 120 recipients at Sungnam area were surveyed and interviewed and result were summarized as follow. The cost of each meal (lunch) was ranged from 1,300 won to 1,500 won and number of attendant at meal service were ranged from 50 to 200 persons. Meal time for lunch begins from 10:30 am to noon because greater portion of people (elderly) didn't take breakfast frequently. Most of the center adapted self-service system. Standard recipe was not developed and meal preparation was controlled under the experiences of volunteer’s. Recording system of, nutrition management, production control, storage and inventory control was not well adapted by most of the center. In order to measure the level of storage, sanitation etc., scorin system in survey was adapted in this study and result are as follow: The score of sanitation of kitchen was lower than dinning area and that of food storage was lowest score. It was suggested that not only financial but also systematical support on management by local government may be necessary to meet the goal of supply nutritionally balanced food at the center. The score given by the recipient on the satisfaction of meal service was rate as 4.8 at the 5-point maximum scale. Meeting friends and share social relationship was major reason (41.6% of the total) of visiting to the center. It is suggested that in order to meet the changes of the patterns of change of social and family structure, the service of the center should be extended in urban area and it is necessary to develop systematic management models for the center.

• Journal of Intelligence and Information Systems
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• v.5 no.1
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• pp.103-123
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• 1999

Input filtering as a preprocessing method is so much crucial to get good performance in time series forecasting. There are a few preprocessing methods (i.e. ARMA outputs as time domain filters, and Fourier transform or wavelet transform as time-frequency domain filters) for handling time series. Specially, the time-frequency domain filters describe the fractal structure of financial markets better than the time domain filters due to theoretically additional frequency information. Therefore, we, first of all, try to describe and analyze specially some issues on the effectiveness of different filtering methods from viewpoint of the performance of a neural network based forecasting. And then we discuss about neural network model architecture issues, for example, what type of neural network learning architecture is selected for our time series forecasting, and what input size should be applied to a model. In this study an input selection problem is limited to a size selection of the lagged input variables. To solve this problem, we simulate on analyzing and comparing a few neural networks having different model architecture and also use an embedding dimension measure as chaotic time series analysis or nonlinear dynamic analysis to reduce the dimensionality (i.e. the size of time delayed input variables) of the models. Throughout our study, experiments for integration methods of joint time-frequency analysis and neural network techniques are applied to a case study of daily Korean won / U. S dollar exchange returns and finally we suggest an integration framework for future research from our experimental results.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.1
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• pp.197-209
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• 2015

The issue of information security within an organization began to be recognized as risk of the organization. Because of this, not only ISO(Information Security Officer) but an executive or CEO were forced to resign. In addition, it brought about heavy financial damage to the company and made the company difficult to restore trust to customers. At a time when inadvertent disclosure of personal information has become accepted as a matter of survival because of having a bad effect within an organization, how the information security specialist causes influence on information protection level of the organization. For these reasons, targeting the information security specialists of various industry sectors, we'll analyse how task performance rate of the information security specialist within an organization cause influence to the information security level. The goal of this study is for the company to raise the task proportion of information security specialist and to improve the information protection level of the organization.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.4
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• pp.1-9
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• 2012

Recently, the central and local government support various improvement projects on existing public buildings and areas. Improving public use and environment of these areas is adequate because financial condition of local city is not enough to build new infrastructures. As one of the projects, Geochang-Eup(Geochang-Gun, Gyeongnam Province) is selected as the project site since most of the public buildings and areas of the city are located close each other in downtown but not streamlined in function and use nor easily accessible. The purpose of this study is to analyze the causes of decline in local city and to present strategies to vitalize the city through improving environment of public areas. And we analyzed the problems by discussion with local officer, field investigation on the site and paper survey. The analysis shows that public infrastructures are grouped by function: administration, education, life support, culture, health, etc, but not well-connected, easily accessible, adequately located, various in use nor enough in quantity. This study summarized the problems into five categories: Access&Linkage, Safe&Comfort, Identity&Image, Usage&Activity and Ownership&Management and proposes strategy in three phases. The first phase is to improve functions and design of public places per each area: more consistent design on public buildings, better civil facilities and better accessibility to public areas. The second is to vitalize of the areas and to improve efficiency in use through linking each other physically and sharing uses. The third is to encourage citizen's participation and by developing civil programs to streamline public areas each other.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.276-284
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• 2009

This paper applies DEA windows analysis in order to determine the efficiency of the Districts of Busan Metropolitan City over time for 5 years (2003 - 2007). This paper used such factors including Number of solutions of civil petitions, Local Tax Collection, and Financial Independent rate as output, Total Labor Costs, Government Employees, Population and Expenditure as inputs. This study concludes that the efficiency of the different District can fluctuate over time to different extents and efficiency of most District decreases from 2003. Indeed, the empirical results reveal that substantial inefficiency exists in some Districts at some point in time. In consequence, this validates the necessity for using DEA windows analysis in preference to an analysis based upon cross-sectional data. This paper shows that Districts' efficiency decreases as Window goes to 1 to 3.

• Women's Health Nursing
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• v.6 no.4
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• pp.506-515
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• 2000

The purpose of this study was to validate abuse outcomes included Nursing Outcomes Classification(NOC) developed by Johnson and Maas at the University of Iowa. A sample of 71 nurse experts working in university affiliated hospitals participated in this study. They were asked to rate indicators that examplified the outcomes on a scale of 1 (indicator is not at all characteristic) to 5(indicator is very characteristic). A questionnaire with an adaptation of Fehring's methodology was used to establish the content validity of outcomes. The results were as follows: 1. All indicators were considered to be 'supporting' and no indicators were considered to be 'nonsupporting'. 2. 'Abuse Recovery : Emotional' attained an OCV score of 0.780 and was the highest OCV score among abuse outcomes. The highest indicator was 'demonstration of positive interpersonal relationship'. 3. 'Abuse cessation' attained an OCV score of 0.739 and was the lowest OCV score among abuse outcomes. The highest indicator was 'physical abuse has ceased'. 4. 'Abuse Protection' attained an OCV score of 0.743 and the highest indicator was 'plans for avoiding abuse'. 5. 'Abuse Recovery: Financial' attained an OCV score of 0.762 and the highest indicator was 'court-ordered benefits received'. 6. 'Abuse Recovery: Physical' attained an OCV score of 0.767 and the highest indicator was 'resolution of physical health problem'. 7. 'Abuse Recovery: Sexual' attained an OCV score of 0.768 and the highest indicator was 'expression of confidence with gender identity'. More outcomes need to be validated and outcomes sensitive to Korean culture need to be developed.

• Quality Improvement in Health Care
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• v.19 no.2
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• pp.80-88
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• 2013

Objectives: With the increase in the number of people who are marginalized in receiving medical services, the role of Seoul National University Hospital as a public hospital is being emphasized. However, many patients are either experiencing delays in receiving medical services or simply being left out as a result of the inaccessibility to the department of social work on part of both the patients and the medical staff. Methods: In order to increase consultation from other departments and the accessibility to the department of social work for the socially marginalized group through early consultation from other departments, the following steps were taken. First, an orientation program for novice medical residents led by clinical social worker was introduced/implemented. Second, posters and brochures on various financial aids programs were produced and distributed. Third, a system of early screening was built/constructed, and once a week rounds and early screening meeting were executed/carried out. Result: The department of social work's rate of consultation from other departments increased by 4.4% compared to last year, while it showed 61% increase for those wards that had an early screening meeting. In addition, the average time of consultation from other departments was reduced by 3.1 days, securing sufficient amount of time for clinical social work services, both in terms of quality and quantity. Conclusion: It is believed that the various promotional activities, along with the strengthening of accessibility to clinical social work services and early consultation on part of social disadvantaged/marginalized group, would undoubtedly help provide quality services to patients and increase their level of satisfaction. In this way, the wards can effectively reduce the number of unnecessary hospital stay days while the hospital can prevent the accumulation of outstanding bills/fees as well as contribute to the publicness of hospitals. The promotion of clinical social work programs in various ways are crucial to ensuring the satisfaction of patients and hospital staff.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.9
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• pp.932-940
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• 2011

This paper presents an integrated analysis of supply chain and financing decisions of multi-national corporation. We construct a model in which multiple currency storage units are installed to manage the currency flows associated with multi-national supply chain activities such as raw material procurement, process operation, inventory control, transportation and finished product sales. Core contribution of this study is to quantitatively investigate the influence of macroscopic economic factors such as exchange rates and taxes on operational decisions. The supply chain is modeled by the Process-Storage Network with recycle streams. The objective function of the optimization is minimizing the opportunity costs of annualized capital investments and currency/material inventories minus the benefit to stockholders interpreted by home currency. The major constraints of the optimization are that the material and currency storage units must not be depleted. A production and inventory analysis formulation, the periodic square wave (PSW) model, provides useful expressions for the upper/lower bounds and average levels of the currency and material inventory holdups. The expressions for the Kuhn-Tucker conditions of the optimization problem are reduced to a subproblem and analytical lot sizing equations. The procurement, production, transportation and financial transaction lot sizes can be determined by analytical expressions after the average flow rates are already known. We show that, when corporate income tax is taken into consideration, the optimal production lot and storage sizes are smaller than is the case when such factors are not considered typically by 20 %.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4609-4614
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• 2015

Background: In recent decades, the prognosis for childhood leukemia has improved, especially for acute lymphoblastic leukemia (ALL). In Thailand, though, the survival rate for ALL is unimpressive. In 2006, standard national protocols for childhood leukemia treatment were implemented. We herein report the outcome of the ALL national protocols and explanations behind discrepancies in outcomes between institutions. Materials and Methods: Between March 2006 and February 2008, 486 children with ALL from 12 institutions were enrolled in the Thai national protocols. There were 3 different protocols based on specific criteria: one each for standard risk, high risk and Burkitt's ALL. We classified participating centers into 4 groups of institutions, namely: medical schools in Bangkok, provincial medical schools, hospitals in Bangkok and provincial hospitals. We also evaluated supportive care, laboratory facilities in participating centers, socioeconomics, and patient compliance. Overall and event-free survival were determined for each group using the Kaplan Meier method. Statistical differences were determined using the log-rank test. Previous outcomes of Thai childhood ALL treatment between 2003 and 2005 served as the historic control. Results: Five-year overall survival of ALL treated using the Thai national protocol was 67.2%; an improvement from the 63.7% of the 12-institute historical control (p-value=0.06). There were discrepancies in event-free survival of ALL between centers in Bangkok and up-country provinces (69.9% vs 51.2%, p-value <0.01). Socioeconomics and patient compliance were key elements in determining the outcome (65.5% vs 47.5%, 59.4% vs 42.9%) (p-value < 0.02). Conclusions: Implementation of standard national protocols for childhood leukemia in Thailand did not significantly improve the outcome of ALL. Factors leading to better outcomes included (a) improvement of treatment compliance (b) prevention of treatment abandonment and (c) financial support to the family.