• Tribology and Lubricants
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• 제36권6호
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• pp.307-314
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• 2020

In this paper, studies on application cases of machine condition monitoring using oil sensors are reviewed. Owing to rapid industrial advancements, maintenance strategies play a crucial role in reducing the cost of downtime and improving system reliability. Consequently, machine condition monitoring plays an important role in maintaining operation stability and extending the period of usage for various machines. Machine condition monitoring through oil analysis is an effective method for assessing a machine's condition and providing early warnings regarding a machine's breakdown or failure. Among the three prevalent methods, the online analysis method is predominantly employed because this method incorporates oil sensors in real-time and has several advantages (such as prevention of human errors). Wear debris sensors are widely employed for implementing machine condition monitoring through oil sensors. Furthermore, various types of oil sensors are used in different machines and systems. Integrated oil sensors that can measure various oil attributes by incorporating a single sensor are becoming popular. By monitoring wear debris, machine condition monitoring using oil sensors is implemented for engines, automotive transmission, tanks, armored vehicles, and construction equipment. Additionally, such monitoring systems are incorporated in aircrafts such as passenger airplanes, fighter airplanes, and helicopters. Such monitoring systems are also employed in chemical plants and power plants for managing overall safety. Furthermore, widespread application of oil condition diagnosis requires the development of diagnostic programs.

• 디지털융복합연구
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• 제13권4호
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• pp.247-252
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• 2015

산업화가 가속화되면서 화석 연료의 사용이 늘어나고 있어 지구 온난화와 기상 이변 등의 문제가 발생하고 있다. 이러한 문제를 해결하기 위한 국제적인 협약이 이루어지는 등 노력은 계속되고 있으나 여전히 화석 연료의 사용은 늘고 있는 추세이다. 공공자전거는 자동차 위주의 교통 시스템이 가지고 있는 문제를 해결하고 사용자의 건강까지 챙길 수 있는 대안으로 제시되고 있다. 본 연구에서는 기존의 공공자전거가 가지고 있는 문제를 해결하고 최근의 스마트폰 사용 트렌드에 맞는 새로운 융복합 공공자전거 시스템을 제안하려고 한다. 본 연구에서 제안하는 공공자전거 시스템은 기존의 시스템에 비해 설치비가 저렴하고 운영비도 적게 드는 장점이 있다. 실제 운영사례를 통해 본 연구에서 제안한 시스템의 효용성을 증명하고자 한다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1288-1293
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• 2009

The TES (Thermal Energy Storage) cooling system utilizing cheaper off-peak electricity has been applied just for building air-conditioning currently and causes limitation of usage rate and inefficiency of national resources utilization. In this regard, more says the necessity to apply TES system in industrial cooling system which is longer using period and wider usage. In this study, we will approve the technical and economical improvement in efficiency of industrial cooling system applied TES system by utilizing cheaper off-peak electricity and it will attribute the promotion of TES system and stabilization of supply and demand of electric power by proving the necessity to develop more efficient industrial cooling system by combining TES system.

• 디지털융복합연구
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• 제20권5호
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• pp.499-512
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• 2022

본 연구는 포스트 코로나 시대에 대비해 안양시 공공도서관이 온라인 미디어를 효과적으로 활용할 수 있는 방안을 제안하고자 하는 목적에서 수행되었다. 이를 위해 2021년 전국 도서관 운영 평가에서 정부 포상을 받은 우수 도서관 5곳의 운영 사례를 분석해 주요 시사점들을 정리하고, 분석 내용들을 바탕으로 안양시 도서관이 온라인 미디어를 활용해 도서관 운영을 활성화 하는 데 도움이 될 수 있는 방안들을 도출하였다. 본 연구는 코로나19 시기 성과들을 바탕으로 우수 도서관으로 선정된 도서관들의 실제 사례를 토대로, 포스트 코로나 시대에 대비해 안양시 도서관의 온라인 미디어 활용 전략을 정리해 제안한 실증적이고 경험적인 연구라는 점에서 의의를 찾을 수 있다.

• 유통과학연구
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• 제21권7호
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• pp.117-129
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• 2023

Purpose: With the number of COVID-19 cases declining and generational differences among how people use mobile apps, including health service apps, the goal of this research is to identify and analyze the factors that affect people's attitudes when using the Halodoc health service app during the third year of the pandemic. Research design, data, and methodology: This study proposes a quantitative analysis method based on PLS-SEM modeling. This study has used a questionnaire survey to collect randomized data from 268 Halodoc users from generations Y and Z in Jakarta. Results: Both the Y and Z generations believe there is a significant usefulness factor in the attitude toward using the application. The start of the pandemic period demonstrates that the urgency of using health service applications is no longer determined by performance expectations, effort, or social panic, but rather by these applications' usability. Conclusions: Even though a health service application is no longer considered an urgent service or a priority need, attitudes, and behaviors in using it emphasize the aspect of long-term benefits. These findings supplement other considerations and understandings in application of the Unified Theory of Acceptance and Use of Technology (UTAUT) model in explaining attitudes and intention behaviors.

• 인터넷정보학회논문지
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• 제19권5호
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• pp.97-105
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• 2018

In this paper, we present our recent effort on the development of a portable OCS system (SCH-mOCS), which provides minimal but essential functionalities of conventional OCS systems. SCH-mOCS is targeted for the environment where Internet connection is not available and fast processing of essential patient information is needed. The main usage could be found at the outdoor environment, such as voluntary medical services at challenged regions. The target of the first usage of the system is in the rural area of Cambodia where medical service and ICT infrastructure is poor. We have been conducting voluntary medical services for 15 years in Cambodia, where the services usually run for 3 days and include outpatient diagnosis/consultation, medication, and simple surgeries. This medical service started in 2002, where about 20 SoonChunHyang University Bucheon Hospital staffs (doctors, nurses, and pharmacists) participated. We realized that a system like SCH-mOCS is needed: we have to consult many patients in a short period, so that a prompt response and prescription to the patients are very important. However, the conventional OCS system is not suitable, because the service is usually conducted outdoor environment where Internet connected computers cannot be installed. Moreover, since the service needs only a subset of the conventional hospital information system and fast system response, application of a full OCS is not practical. The adequate system is a bare minimal OCS system, with very simple and quickly manageable patient admission, consultation, and prescription functionalities. In this paper, we describe hardware as well as the software aspect of a mini-OCS we have developed for the purpose. We named the system SCH-mOCS (SoonChunHyang mini-OCS). We also describe the usage scenario of SCH-mOCS in order to demonstrate that the system is general enough to apply for other similarly challenged regions.

• 한국농공학회논문집
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• 제64권2호
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• pp.27-35
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• 2022

Based on the current status of groundwater usage in the dry season through field surveys, this study tried to suggest countermeasures to reduce groundwater usage and to improve the water quality of baseflow from agricultural fields. For this purposes, basins with water curtain cultivation preceded were targeted where decreases of groundwater due to continuous use of groundwater in spring and winter annually observed. From monitoring groudwater usage of the study watershed, 130,058, 130,105 m³/day of water was pumped in during the water curtain cultivation period (October-February) in the Shindun, Seokwon watershed respectively. And the pilot application of the smart automated sensor-based water curtain cultivation system (smart WC system) developed in this study to reduce groundwater consumption has been conducted. As a result, the efficiency of the smart WC system when threshold temperature is set as 6.3 ℃ was 21.1% compared to conventional cultivation and efficiency increased as threshold temperature gets lower. Lastly, in this study, culvert drainage and Bio-filters were installed and rainfall monitoring was performed 15 times in order to analyze the baseflow securement and pollutant loads behavior. As a result, the test-bed with culvert drainage and Bio-filter installed together generated 61.4% more baseflow (4.974 m³) than the test-bed with only culvert drainage was installed (3.056 m³). However, the total pollutant load of all water quality contents (BOD, COD, T-N, TOC) except for the SS and T-P was found to be greater in the culvert drain and Bio-filter installed than in the culvert drain test-bed.

• 한국농공학회논문집
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• 제58권6호
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• pp.31-38
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• 2016

The purpose of this study was to assess nonpoint sources (NPS) pollution affected by liquid manure and regulating gate in a small agricultural watershed. The study area, which is a wide plain farmland, was operating by the Buyong regulating gate in order to maintain irrigation water level during irrigation period. Consequentially, runoff only occurs through the gate at each event in rainy season for avoiding farmland inundation. In addition, the usage ratio of liquid manure in the study area has been increased greatly since 2014. Discharge loads at the Hwaingsan bridge subwatershed were 1.2 times for T-N, 4-10 times for T-P, and 3-8 times for TOC compared with the Soyang watershed (control) during study period. The reason was that NPS pollutants from upper Gpeun and Sangri bridge subwatersheds, which are widely spraying with livestock liquid manure, were stack at this subwaterehd because of regulating gate in non-rainy seasons. A number of agricultural watersheds in Saemangeum watershed are affected by regulating gate and vigorous livestock activities so that substantial management schemes under controling regulating gate are needed for minimizing livestock related NPS.

• Environmental Engineering Research
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• 제25권3호
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• pp.267-273
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• 2020

This Hydrokinetic energy system is the process of extracting energy from rivers, canals and others sources to generate small scale electrical energy for decentralized usage. This study investigates the application of Soil and Water Assessment Tool (SWAT) in Geographical Information System (GIS) environment to evaluate the theoretical hydrokinetic energy potentials of selected Rivers (Asa, Awun and Oyun) all in Asa watershed, Kwara state, Nigeria. SWAT was interfaced with an open source GIS system to predict the flow and other hydrological parameters of the sub-basins. The model was calibrated and validated using observed stream flow data. Calibrated flow results were used in conjunction with other parameters to compute the theoretical hydrokinetic energy potentials of the Rivers. Results showed a good correlation between the observed flow and the simulated flow, indicated by ash Sutcliffe Efficiency (NSE) and R² of 0.76 and 0.85, respectively for calibration period, and NSE and R² of 0.70 and 0.74, respectively for the validation period. Also, it was observed that highest potential of 154.82 MW was obtained along River Awun while the lowest potential of 41.63 MW was obtained along River Asa. The energy potentials obtained could be harnessed and deployed to the communities around the watershed for their energy needs.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3379-3391
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• 2013

The usage and types of chemicals being developed, with diversified new exposure of workers, are of natural concern to occupational disease. In Korea, with industrialization, application of many chemicals has increased. A large proportion of mortality and disease is due to cancer, and the causal hazardous agents include chemical agents, like heavy metals and so on. Due to the long latency period with malignancies and the fact they are usually found after workers' retirement, it is suggested that management policies must be established to prevent occupational cancers occurring among workers in Korea. To give a general description about the efforts to prevent the occupational cancer with exposure to chemicals, articles on the trends of occupational cancers were reviewed and summarized with related research and efforts for prevention in Korea. It is important to improve the understanding of occupational cancer and help to maintain sustainable and appropriate measures to guarantee workers safety and health.