• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2020-2021
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• 2003

Korea Research Institute of Standards and Science (KRISS) has developed a Web-based, remote, Internet calibration system to calibrate the Fluke 5700A/5720A calibrator using a transportable standard: specifically, multifunction transfer standard 4950. Although the uncertainty for the Internet calibration is up to two times larger than that using conventional manual calibration, it has many advantages: no need to transport the customer equipment, a reduction in the calibration service time, a directly enforced traceability to the national standards, convenience, and ease of use for the customers.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.221-226
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• 2006

Around 2002, the United States Coast Guard (USCG) identified a need to re-capitalize their Reference Station (RS) and Integrity Monitor (IM) equipment used in the Nationwide Differential Global Position System (NDGPS). Commercially available off-the-shelf differential RS and IM equipment lacked the open architecture required to support long-term goals that include future system improvements such as use of new civil frequencies on L2 and L5 and realization of a higher rate NDGPS beacon data channel intended to support RTK. The first step in preparing for this future NDGPS was to port current RTCM SC-104 compatible RS and IM functionality onto an open architecture PC-based platform. Trimble's product Charisma is a PC-based RS and IM software designed to meet these USCG goals. In fact USCG engineers provided key designs and design insights throughout the development. We cannot overstate the contribution of the USCG engineers. Fundamental requirements for this effort were that it be sufficiently flexible in hardware and software design to support fluid growth and exploitation of new signals and technologies as they become available, yet remain backward compatible with legacy user receivers and existing site hardware and system architecture. These fundamental goals placed an implicit adaptability requirement on the design of the replacement RS and IM. Additionally, project engineers were to remain focused on sustaining the high level of differential GPS service that 1.5 million legacy users have come to depend on. This paper will present new hardware and software (i.e., Trimble's Charisma software) architecture for the next generation NDGPS RS and IM. This innovative approach to engineering on an open architecture PC-based platform allows the system to continue to fulfill legacy NDGPS system requirements and allows the USCG and others to pursue a scalable hardware re-capitalization strategy. We will use the USCG's recapitalization project to explain the essential role of the Charisma software.

• 정보처리학회논문지A
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• 제17A권2호
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• pp.81-92
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• 2010

진동 정보를 통해 기계 설비의 상태나 고장 유무를 판단하는 연구들이 다수 진행 중에 있는데, 대부분의 연구에서는 설비에 대한 진동을 모니터링하거나 고장 유무를 판별하여 사용자에게 알리는 수준이다. 본 논문에서는 진동에 의한 고장 진단과 판별을 보다 정교하게 수행하는 선박 엔진의 고장 감지 기법과 시스템을 제안하였다. 일차적으로 이중적 진동 정보 판별 기법을 적용하여 진동 정보를 확인한 다음에 고장 유무를 검사한다. 만일 고장이 발생한 경우에는 진동 정보의 오류 부분만을 이용하여 고장 진동 파형에 대한 오차 범위를 기준으로 어떤 유형의 고장인지를 판별할 수 있는 기법을 적용하였다. 또한 선박의 진동 경향 분석과 엔진 안전 보존을 목적으로 진동 정보를 데이터베이스에 저장하고 추적할 수 있도록 시스템을 구현하였다. 제안 시스템을 선박 엔진의 고장 판별 유무와 고장 진동 파형 감별 인자에 대해 실험을 수행한 결과 고장 유무 판별은 약 100% 정확성을 가졌고 고장 진동 파형의 유형 인식에서는 약 96% 정확성을 가졌다.

• Advances in Energy Research
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• 제7권1호
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• pp.1-19
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• 2020

Energy consumption of air-conditioning and refrigeration systems is responsible for about 25 to 30% of the energy demand especially in hot seasons. This equipment is mostly electricity dependent and their use in principle affects negatively the environment. Enhancing the energy efficiency of the existing equipment is important as one of the measures to reduce environment impacts. This paper reports the results of an experimental study to evaluate the impacts of the use electronic expansion valve and variable velocity compressor on the performance of vapor compression refrigeration system. The experimental rig is composed of two independent circuits one for the vapor compression system and the other is the secondary fluid system. The vapor compression system is composed of a forced air condenser unit, evaporator, hermetic compressor and expansion elements, while the secondary system has a pump for circulating the secondary fluid, and an air conditioning heat exchanger. The manufacturer's data was used to determine the optimal points of operation of the system and consequently tests were done to evaluate the influence of variation of the compressor velocity and the opening of the expansion device on the performance of the refrigeration system. A fuzzy logic model was developed to control the rotational velocity of the compressor and the thermal load. Fuzzy control model was made in LabVIEW software with the objective of improving the system performance, stability and energy saving. The results showed that the use of fuzzy logic as a form of control strategy resulted in a better energy efficiency.

• 한국안전학회지
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• 제38권3호
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• pp.102-109
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• 2023

Following the accident at Fukushima, the true impact of multi-unit accidents came to light. Accordingly, research related to multi-unit accident effect analysis, risk evaluation, and accident prevention/prevention technology has been conducted. Specific examples are mobile/fixed equipment such as multi-barrier accident coping strategy (MACST) and diverse and flexible coping strategies (FLEX), which have been introduced and installed in multi-units for preventing and mitigating multi-unit accidents. These strategies are useful for enhancing the safety of nuclear power plants (NPPs); however, a more efficient strategy is required in terms of the costs of physical and human resources. To effectively and efficiently mitigate an increase in multi-unit accidents, it is necessary to not only to utilize mobile/fixed equipment but to also use crosstie options with resources that already exist at NPPs. Therefore, we analyzed the current international and domestic status of crosstie systems technology and propose a method to evaluate feasibility alongside risk based on a multi-unit probabilistic safety assessment (PSA). To analyze the international and domestic status of crosstie systems technology, actual cases and related research were studied, and a list of potential crosstie safety resources was derived. Additionally, a case study was performed on crosstie cases of two systems within the assumed six units on-site under a multi-unit accident, and a multi-unit PSA-based risk evaluation method is proposed.

• 한국물환경학회지
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• 제31권2호
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• pp.151-158
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• 2015

The aim of this research is to derive an optimum operating condition for the thermal solubilization equipment that is employed to increase concentration of soluble organic materials and to assess whether it would be possible to use the waste sludge generated by thermal solubilization reaction as an external carbon source in biological denitrification process. For the purpose, we have constituted a laboratory-size thermal solubilization equipment and have assessed thermal hydrolysis efficiency based on various reaction temperature and reaction time. We have also derived SDNR using the waste sludge generated by thermal solubilization reaction through a batch experiment. As a result of research, the highest thermal hydrolysis efficiency of about 42.8% was achieved at $190^{\circ}C$ of reaction temperature and at 90 minutes of reaction time. And when SDNR was derived using the waste sludge, the value obtained was $0.080{\sim}0.094\;g\;NO_3{^-}-N/g\;MLVSS{\cdot}day$, showing SDNR that is higher than that obtained by the results of existing researches that used common wastewater as an external carbon source. Accordingly, in view of the fact that food wastes vary quite a bit in characteristics based on the area they are generated from and seasonal change, it seems that a flexible operation of thermal solubilization equipment is required through on-going monitoring of food wastes that are imported to food wastes recycling facilities.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2020년도 추계학술대회
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• pp.80-81
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• 2020

코로나 19로 인하여, 전 세계 경제가 위기 상황에 직면해 있으며 수출을 위주로 하는 산업에 대해서는 기업의 생존을 고민해야 하는 상황이다. 정부와 업계에서는 여러 방면으로 수출 활성화를 위해 노력하고 있으며, 비대면 수출 활동에 제약이 발생하면서 비대면으로 수출 마케팅을 실행할 수 있는 여러 방법들을 고민하고 있다. 그중에서도 온라인을 통한 전시회를 진행하는 부분에 대해서 여러 산업에서 다방면으로 연구가 이루어지고 있다. 특히 조선해양 산업은 수출 주력산업으로, 전 세계적으로 개최되는 오프라인 전시회가 마케팅의 중요한 기회의 장이었고, 이를 대체할 수 있는 온라인 전시회 활용이 절실한 실정이다. 본 연구에서는 조선해양 산업에 적합한 온라인 전시장 구축에 필요한 여러 요소 기술들인 AR, VR, MR 등에 대해서 알아보고, 온라인 전시회에 어떻게 접목되는지.

• 수산해양기술연구
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• 제59권4호
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• pp.328-335
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• 2023

In this paper, among the various facilities used in marine farming, young bivalves of the Mytilus galloprovincialis of marine farming was placed on the deck of the fishing vessel to evaluate the environment conditions and drive shaft movement by rolling affecting the separator for the young bivalves and a clean process. There were a few studies on stress analysis of development facilities because it was difficult to access the fishing site due to the use of imported equipment and the lack of development of domestic equipment. In this study, stress analysis of the fixed part of separator for young bivalves and its adjacent part was performed on various phases when the vessel was tilted by rolling using the finite element method. In addition, the structural safety of the internal blade under the driving conditions according to the movement of the drive shaft by the hydraulic motor was confirmed through structural analysis. As a result, the connection part between the deck and the separator by rolling was confirmed to have higher stress than that of other parts due to stress concentration. In addition, it was confirmed that the maximum stress occurred on the connection part between blades. Even though the safety of the separator for marine farming was confirmed by structural analysis, it is necessary to comprehensively consider the age of vessels, the material of the deck, and the corrosion of the deck.

• PNF and Movement
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• 제15권2호
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• pp.115-124
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• 2017

Purpose: Researchers found that blocks of evidence-based practice (EBP) implementation lacked opportunities for EBP education. The study found that physical therapists had negative views of research as well as their roles in EBP, lacked confidence in EBP, and had limited access to web-based materials. The purpose of this study was to highlight the importance of information research technology for efficient EBP in a clinical environment. Methods: The web-based information research technologies that should be used for sustainable EBP include: the clinical practice guideline (CPG) and PubMed's My NCBI service. Journal mailing services and other academic information sources should also be used to gather information from RSS feeds. An EBP library or archive must be created. A site that provides EBP-specific information is also needed. Results: We should usually do EBP. Practitioners must learn and use information technologies that will help them improve their EBP skills. Conclusion: Facilitating EBP implementation and building an EBP system require related education as well as a practical work environment and equipment. However, the highest priority is individual efforts and trial. Information technology will complement the lack of time. It is important to use information research technology to overcome real obstacles. Lasting EBP must use a number of web-based information research technologies to overcome the practical challenges encountered in EBP implementation.

• Safety and Health at Work
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• 제8권3호
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• pp.246-249
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• 2017

Health-care workers are at risk of exposure to occupational infections with subsequent risk of contracting diseases, disability, and even death. A systematic collection of occupational disease data is useful for monitoring current trends in work situations and disease exposures; however, these data are usually limited due to under-reporting. The objective of this study was to review literature related to knowledge, risk perceptions, and practices regarding occupational exposures to infectious diseases in Malaysian health-care settings, in particular regarding blood-borne infections, universal precautions, use of personal protective equipment, and clinical waste management. The data are useful for determining improvements in knowledge and risk perceptions among health-care workers with developments of health policies and essential interventions for prevention and control of occupational diseases.