• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.153-163
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• 2007

An adaptive framework paradigm where the bandwidth values of the ongoing calls vary according to the trafficsituations is one of the promising concepts for overcoming poor resource conditions due to handoffs in mobilecellular networks. However, quantifying the level of bandwidth degradation of the ongoing calls in an adaptiveframework is important in view of Quality of Service (QoS) Provisioning. Therefore we introduce new QoSparameters, the Degradation Degree Ratio (DDR), which represents the average portion of the degradationdegree during degradation pehod of a call, and the Degradation Area Ratio (DAR), which represents the averageratio of a call's degradation level considering both the period and the degree of degradation jointly in multi-levelbandwidth service. We also develop a new analytical model for estimating the QoS measures such as theDegradation Pehod Ratio (DPR), DDR and DAR. We show how to calculate the QoS measures and illustrate themethod by numerical examples. The proposed model can be used to determine the optimal parameter of theCAC scheme and analyze the sensitivity ofthe QoS parameters in adaptive networks.

• Research in Community and Public Health Nursing
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• v.22 no.3
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• pp.262-271
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• 2011

Purpose: The study was conducted in order to identify factors influencing depression and quality of life in elderly customized home visiting health services. Methods: A total of 442 people participated as the subjects of this study. Data were collected during the period from June to September in 2010 and the measurement tool used for this study was the customized home visiting health service recording sheet recommended by the Ministry of Health. Data were analyzed using t-test, one-way ANOVA, Pearson correlation coefficients, and stepwise multiple regression with SPSS/WIN 17.0. Results: Depression was correlated negatively with quality of life. According to the results of this research, factors influencing depression in elderly customized home visiting health services were quality of life, customized home visiting health service period, and IADL. Factors influencing quality of life in elderly customized home visiting health services were depression, joint exercise capacity, age, connection to volunteerism, IADL and ADL. Conclusion: The results of this study can be leveraged as complementary information for the effective management of customized home visiting health service subjects. Moreover, the results can be used as a reference for future studies.

• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.39-47
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• 2006

In most of supply chain planning practices, the estimated demands, which are forecasted for each individual period in a forecasting window, are regarded as deterministic. But, in reality, the forecasted demands for the periods of a given horizon are stochastically distributed. Instead of using a safety stock, this study considers a direct control of service level by choosing the demand used in planning from the distributed forecasted demand values for the corresponding period. Using the demand quantile and echelon stock concept, we propose a simple but efficient heuristic algorithm for multi-echelon serial systems under service level constraints. Through a comprehensive simulation study, the proposed algorithm was shown to be very accurate compared with the optimal solutions.

• Fire Science and Engineering
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• v.22 no.4
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• pp.61-64
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• 2008

This paper studied on the response characteristics depending on service life of ionization smoke detector. The experimental samples used ionization smoke detectors (360 EA) for over 5 years which were influenced by environment set up with fire objects. The experimental method performed operate and non-operate test according to 'Type Approval and Technical Regulation of Detector (KOFEIS 0301)', for estimate the response characteristics of ionization smoke detector depending on service life. The results showed that their response characteristics were rapidly decreasing when the longer their using period. Accordingly, it is desirable that ionization smoke detector has to be changed for early fire detection when passed their service life.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.4
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• pp.336-344
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• 2007

A method is developed to evaluate partial safety factors for armor units, by which uncertainties of random variables in reliability function as well as wave height distribution with service periods could take into account straightforwardly. It is found that partial safety factors for resistance and wave height are correctly increased with improving target levels on failure of coastal structures at the same return and service periods. Therefore, it nay be possible to determine design variables through the same processes as those of deterministic method by using the partial safety factors for resistance and wave height evaluated in this paper, since uncertainties of random variables and the effects of service periods and target probability failure are directly considered in the processes of evaluation of partial safety factors.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.168-173
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• 2012

The objective of this study was to investigate the problems and benefits associated with the implementation of HACCP on livestock product of plants in Korea. The survey was carried out by randomly selecting 115 HACCP accredited meat processing plants, all across the country. A total of 105 complete responses were selected for analysis. The results were as follows: approximately 60% of the respondents employed less than twenty workers. The average period of operating HACCP system was 3.4 years. The respondents replied that the major incentive to implement the HACCP system was to improve hygiene management ability. More than half of the respondents (59.05%) claimed that the implementation of the HACCP system cost less than 400 million won, and the highest investment in terms of cost was the freezer/refrigerator. In the preparation period taken to implement the HACCP system, the 6-12 mon category had the highest percentage (55.24%). Most respondents replied that there was an increase in the customer satisfaction, plant image and turnover, after HACCP implementation (p<0.05). A total of 98.09% of respondents had the opinion that their plant workers had improved in their understanding of food hygiene by HACCP implementation (p<0.05). Approximately 79% of respondents indicated that customer complaints decreased, as a result of HACCP implementation.

• The Korean Journal of Emergency Medical Services
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• v.28 no.1
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• pp.63-76
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• 2024

Purpose: To analyze trends related to demography and EMS and to provide supporting data for the appropriate deployment of EMS providers. Methods: In this cross-sectional study, data on patients transported by 119 EMS, demographics, and EMS factors were collected using the Korean Statistical Information Service (KOSIS) and the National Fire Agency annual report from 2017 to 2021. Results: During the study period, the total number of patients and those with severe disorders transported via 119 EMS showed an increasing trend. The total fertility rate and population during the same period tended to decrease, and the population density and number of households increased; however, there was a disparity between regions. The main demographic factors affecting the number of patients transported were population density and total fertility rate, while the main EMS factors were the number of ambulances and provision of emergency medical information services(hospital guidance, pharmacy information, and first aid guidance). Conclusion: From the perspective of EMS providers' force deployment, it is necessary to consider population density, population, number of households, total fertility rate, and number of emergency medical institutions and to strengthen the role of diverting the use of 119 EMS by minor patients by providing emergency medical information.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.235-236
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• 2010

Since many structures in the sea environment are damaged by chloride, appropriate repair strategy is required. Therefore in the paper, optimum period for the RC structure's repair is calculated with consideration of economic efficiency. Moreover, when the concrete members are repaired with the other material such as polymer mortar forr section restoration, their expected service life also calculated to predict more accurate repair period during the life span.

• Journal of the Korea Convergence Society
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• v.11 no.4
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• pp.323-332
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• 2020

The purpose of the study is to investigate the impact on service quality of caregivers. 200 caregivers in 6 elderly care facilities located in J city were instructed to answer structure questionnaires, and the collected data was analyzed by T-test, ANOVA, Pearson correlation, and regression analysis. The results of the study show significant differences in service quality depending on their religion, education level, form of employment, employment period, health status, and access to staff lounge. Work environment shows positive correlation to service quality, whereas job stress shows negative correlation. Variables shown to affect service quality are, from the most powerful to the least, human environment, physical environment, form of employment, employment period, and education level with explanatory power of 42.6%. The results of the study suggest the need for putting in individual effort and improving work environment specifically to unique characteristics of each institution and looking into various ways to intervene in financial support policies in order to promote service quality of caregivers.

• Convergence Security Journal
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• v.7 no.2
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• pp.73-80
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• 2007

The fact that since Internet has been spreaded widely to people, Many security problems also have been grown too much. Due to sudden growth, administrator's responsibility for secure network and services has been growing more and more. This paper represents how to prevent account which didn't use for long period on multi domains environment using service log analysis. hence administrator can find security hole on systems and can dealing with it. The Service Log Analyzer is that loading log file which are written by each service and analyzing them. as a result it makes a list named Used User List contains a number of account names which uses specific services. When the time has come - means cron job schedule time, User Usage Shifter is the next runner. it's mission is finding the person who didn't used service for a specific period of time. Then modifying the expire day of the account information.