• Industrial Engineering and Management Systems
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• 제12권3호
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• pp.281-287
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• 2013

In this paper, we introduce a roots method that uses the roots inside the unit circle of the associated characteristics equation to evaluate the steady-state system-length distribution at three epochs (pre-arrival, arbitrary, and post-departure) and sojourn-time distribution in GI/PH/1 queueing model. It is very important for an air base to inspect airplane oil because low-quality oil leads to drop or breakdown of an airplane. Since airplane oil inspection is composed of several inspection steps, it sometimes causes train congestion and delay of inventory replenishments. We analyzed interarrival time and inspection (service) time of oil supply from the actual data which is given from one of the ROKAF's (Republic of Korea Air Force) bases. We found that interarrival time of oil follows a normal distribution with a small deviation, and the service time follows phase-type distribution, which was first introduced by Neuts to deal with the shortfalls of exponential distributions. Finally, we applied the GI/PH/1 queueing model to the oil train congestion problem and analyzed the distributions of the number of customers (oil trains) in the queue and their mean sojourn-time using the roots method suggested by Chaudhry for the model GI/C-MSP/1.

• 설비공학논문집
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• 제21권11호
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• pp.591-598
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• 2009

The service quality with the various building equipments tends to depend on the individual superintendent's capability and efforts generally and this often lead to poor maintenances and managements of them. N-BMS(Networked Building Management System), proposed in this study, is a new type of building management method, which links principal equipments within many buildings into a communication network and carries out several significant missions such as fault detection, deterioration diagnosis and control the equipments and so on, as well as monitoring which is the main and unique purpose of the conventional BMS. How to construct the N-BMS was considered to keep performance of equipments high and thus to save energy and resource. LCC(Life Cycle Cost) based analysis was also performed in order to verify the effects of some maintenance and management works for the building HVAC systems.

• 한국항공운항학회지
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• 제32권1호
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• pp.28-38
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• 2024

Due to globalization, the air transport industry plays a key role in the global economy. In particular, the air transport industry is highly dependent on human resources, and the capabilities of the cabin crews in managing safety and providing service in a cabin depend on the service quality and the success of the company's human resource management. Therefore, systematic support and interest in competitive key personnel are believed as very important factors. Airlines need to improve the work engagement of airline cabin crew through organizational supportive efforts. Thus this paper surveyed 309 cabin crews who worked at low cost carrier and conducted an empirical analysis based on survey results. The study validates hypotheses pertaining the relationship between organizational identification and job commitment of cabin crew according to the airline's perception of organizational support. The comprehensive analysis reveals that perceived organization support has a significantly positive impact on cabin crews' work engagement.

• 한국항공운항학회지
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• 제26권3호
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• pp.66-76
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• 2018

Terminal 2 of Incheon in'tl airport had made a grand opening since January 2018. Terminal 2 is currently operated by mainly Korean airline in cooperation with such skyteam members as Delta airline, Air France and Royal Dutch KLM. It is expected another three skyteam member airlines join the separate operation at terminal 2 since this coming winter. It is believed very meaningful research to analyze how separate operation of Global alliance of airlines affects the global brand image of an organization. To find out such effect, researchers have made an empirical analysis of perception of airline staffs working at terminal 2. This paper has focused on how the staffs perceive airline service quality in the changed working environment and on how significantly their perception on service has an effect on airline's global brand image with such moderating variables as organizational efficacy and organizational trust. According to empirical analysis using structural equation modeling, it was proven the variable of responsiveness among perceived airline service qualities had a direct significant effect on formulating airline's global brand image associated with joint venture between Korean airline and Delta airline. However, the other variables had a indirect significant effect on global brand image with moderating effects.

• 한국식품과학회지
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• 제54권2호
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• pp.196-202
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• 2022

본 연구에서는 증편의 발효효모의 급원인 막걸리의 첨가량을 달리하여(50, 100, 150, 200 mL) 증편의 품질 특성과 관능적 특성을 평가하고 증편제조 표준화의 기초자료를 제시하고자 하였다. 막걸리 첨가량을 달리한 증편의 수분함량은 막걸리의 첨가량에 따른 수분함량의 유의적인 차이는 나타나지 않았다. 반죽과 증편의 pH는 발효가 진행됨에 따라 감소하다가 증숙 후 증가하는 경향을 나타내었으며, 막걸리 첨가량이 증가함에 따라 감소하였다. 증편의 L값은 막걸리의 첨가량이 증가할수록 감소하였고, a값은 막걸리 첨가량에 따른 유의적인 차이는 나타나지 않았으며, b값은 막걸리의 첨가량이 증가할수록 증가하였다. 증편의 비체적은 막걸리 첨가량이 증가할수록 증가하다가 M-150에서 최대치를 나타내었으며, 증편의 팽창률은 M-200이 가장 낮게 측정되었고 M-200을 제외한 다른 군간의 유의적인 차이는 나타나지 않았다. 기공수는 막걸리의 첨가량이 증가할수록 감소하였고, 기공의 크기는 막걸리 첨가량이 증가함에 따라 증가하였다. 증편의 경도는 막걸리의 첨가량이 증가함에 따라 감소하였다. 부착성(Adhesiveness)은 M-50의 부착성이 가장 크게 측정되었다. 증편의 탄력성(Springness)과 응집성(Cohesiveness)은 막걸리의 첨가량이 증가함에 따라 증가하였으며, 씹힘성은 막걸리의 첨가량이 증가함에 따라 증가하는 경향을 나타내었다. 검성은 막걸리의 첨가량이 증가함에 따라 감소하였다. 증편의 관능평가 결과 M-150이 검사를 실시한 모든 항목에서 가장 높은 점수를 나타내었다. 결론적으로, M-150군의 배합 비율로 증편을 제조하면 증편 내부의 기공형성이 가장 잘 이루어지고 특유의 식감과 향미를 부여하며, 이는 품질 특성 및 기호도에도 가장 바람직한 영향을 줄 것으로 사료된다. 또한, 본 연구는 향후 쌀 소비 촉진을 위한 다양한 증편연구에 기여할 수 있는 기초자료가 될 것으로 생각된다.

• 환경영향평가
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• 제11권1호
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• pp.25-36
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• 2002

The purpose of this study is to assess the environmental carrying capacity of Chongju City for the environmental management and the urban growth management. The urban environmental carrying capacity assessment of the city by the index of ecological footprint(EF), shows that the ecosystem of the city has been overloaded and most of the deficiencies has come from outside of the city. The EF index, the area of land per capita required for production and consumption in the city, was 1.731 ha per capita in 1989 and 1.901 ha per capita in 1999. On the other side, the ecologically productive land is 0.0175 ha per capita. It means that every citizen owes 1.88 ha per capita to the ecosystem in 1999. The land consumption of the city has increased by 0.1705 ha per capita during the last 10 years. The capacity of infrastructure and the service supply estimated by the Onishi model does not exceed the demand of the city in 1999. But the rapidly increasing population and fast urban growth need the expansion of the capacity. The water supply capacity of the city appears to be sufficient in 1999, but the water supply demand will increase in the future. The capacity of sewage treatment facilities seems to be sufficient, but the higher level of sewage treatment facilities should be adopted for the improvement of water quality as the generation of sewage will increase and its characteristics will also make the wastewater treatment difficult. Due to the decrease of solid waste generated, the land fill capacity for solid waste disposal is not insufficient at present, but the capacity will be saturated in the near future. Therefore, the scientific management system of solid wastes should be introduced. The air quality of the city meets both the national air quality standard and WHO recommendation standard, but the strong regulation and control of automobile emission gas such as CO, $CO_2$, NOx and HC is required for clean air.

• 한국농촌건축학회논문집
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• 제22권3호
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• pp.49-60
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• 2020

The purpose of this study utilizes the service design methodology centered on the lives and experiences of rural residents, who are the main beneficiaries of the service, to derive specific problems and needs, and to propose a service improvement plan suitable for the rural residential environment. The study selected Dosan 2-ri Village, Hongseong-gun, Chungcheongnam-do as the target of the survey, used personas and Customer Journey map of service design method to derive specific core issues and insights from the village residents. By developing this, the final five service directions for 'Air care service', 'Self-driving garbage collection and treatment service', 'Emergency/disaster networking service', 'Contaminant removal service' and 'Mobility share service' were derived and presented according to each key keyword. This study is not just a study to grasp the actual conditions of the rural residential environment, but it focuses on the lives and experiences of rural residents and extracts elements that can respond to changes in the lifestyles and patterns of the residents. It can be used as a basic material for more realistic improvement of rural residential environment and service development research. Most of the existing studies on residential environments and spaces is focused on urban areas, and there is a limit to the use of rural areas in residential areas. Therefore, by making recommendations for improvement of residential environment services suitable for rural areas and by creating residential spaces and environments in rural areas in a comfortable and safe manner, it is thought that it is possible to contribute to improvement of satisfaction in rural areas and improvement of healthy housing welfare as well as to improvement of the quality of life of residents of rural areas.

• 한국항행학회논문지
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• 제23권5호
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• pp.473-480
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• 2019

스마트 홈은 가정의 가전제품, 에너지 소비 장치, 보안기기 등 모든 사물을 통신망으로 연결해 모니터링 및 제어할 수 있는 기술이다. 스마트 홈은 자동제어 뿐 아니라 상황과 사용자의 취향을 학습하고, 이에 맞는 결과를 스스로 제공하는 방향으로 발전하고 있다. 본 논문은 사용자의 행동을 감지하여 사용자의 특성에 맞는 쾌적한 실내 환경 제어 서비스를 할 수 있는 모델을 제안하였다. 전체 시스템 구성은 센서와 와이파이를 탑재한 ESP8266, 실시간 데이터베이스인 firebase, 스마트 폰 어플로 구성된다. 본 모델은 사용자가 가전기기 작동시의 학습모드, 학습 결과를 통한 학습 제어, 실내와 실외 센서의 값을 이용한 자동 환기 등의 기능으로 구분된다. 학습은 에어컨, 가습기, 공기청정지 등 가전기기 제어시의 온도와 습도에 대한 이동 평균을 이용하였다. 본 시스템은 데이터베이스에 지속적으로 수집된 데이터를 다양한 기계학습과 딥 러닝을 통해 사용자의 특성을 분석하고 예측하여 보다 고 품질의 서비스를 제공할 수 있다.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.323-334
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• 2020

The quality of hospital services remains a concern of both the manager and the patient. The study aims to identify factors affecting outpatient satisfaction at private general hospitals in Ho Chi Minh City, establishing a scale for measuring them. Some 450 outpatients who were treated in five top private hospitals in Ho Chi Minh city (HCMC) in 2019 - An Sinh General Hospital, Hoan My General Hospital, Columbia Asia International Hospital, FV Hospital, and Vu Anh International General Hospital - were interviewed directly in the last quarter of 2019 to obtain the information. The SERVPERF model, plus the cost, together with the SPSS software, have been used to process information by Cronbach's alpha analysis, Exploratory Factor analysis, and linear regression analysis. The results show that there are five factors influencing outpatient satisfaction at private general hospitals in HCMC, in which four factors affects positively in the order of decreasing importance: treatment outcome, doctors and nurses' professional capacity, facilities and environment of the hospital, hospital care, and the treatment time factor affects negatively. The results of the study provide private hospital in HCMC managers with a number of suggestions to increase the level of hospital service quality, so that increase outpatients satisfaction.

• 한국군사과학기술학회지
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• 제13권5호
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• pp.903-909
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• 2010

ADAS is the air defense control system performing air surveillance and identification of ROK and near air. This system is self-developed by Air Force, currently operated successfully as the alternative system of MCRC. ADAS processes converting and combining transferred the real time radar data detected by radars. additionally, it displays significant radar data as producing in tracks. Then, it uses the message queue for IPC(Inter Process Communication). the various tactical data processed in the server is ultimately send to the network management process through the message queue for transmitting to the weapon director console. the weapon director receives this transmitted tactical data through the console to execute air defense operations. However, there is a problem that data packet is delayed or lost since the weapon Director does not receive as the amount of tactical data from the server overflowed with air tracks and missions increased. This paper improved the algorism to display and transmit the various tactical data processed from ADAS server to numbers of the weapon director console in the real time without any delay or lost. Improved the algorism, established at exercise, the development server in the real operation network and the weapon director console, is proved by comparing the number of sending tactical data packets in the server and receiving packets in the weapon director.