• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1082-1084
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• 1998

In this paper, we developed a diagnosis device for ZnO arrester to detect on-line leakage current and acquire data from the power distribution system. The arrester is important power equipment used in power transmission and distribution systems to protect the generator and the main transformer from surge and overvoltage. First of all we developed a diagnosis device for ZnO arrester leakage current. And then we detect the total leakage current by the developed device without disconnecting the arrester ground wire and analysis the 3rd order harmonic by Fast Fourier Transform(FFT) to diagnose the ZnO arrester deterioration. With measuring the total current and the resistive current of power distribution system in operation, we analysis the trend of resistive current component in the total leakage current. We expect the result will be promote the method to protect electrical utility and customer from accident.

• Geomechanics and Engineering
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• 제12권2호
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• pp.239-255
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• 2017

Various centrifuge model tests on the pile foundations were performed to investigate fundamental characteristics of a pile-soil-foundation system recently, but it is hard to find numerical analysis results of a pile foundation system considering the nonlinear behavior of soil layers due to the dynamic excitations. Numerical analyses for a pile-soil system were carried out to verify the experimental results of centrifuge model tests. Centrifuge model tests were performed at the laboratory applying 1.5 Hz sinusoidal base input motions, and nonlinear numerical analyses were performed utilizing a finite element program of P3DASS in the frequency domain and applying the same input motions with the intensities of 0.05 g~0.38 g. Nonlinear soil properties of soil elements were defined by Ramberg-Osgood soil model for the nonlinear dynamic analyses. Nonlinear numerical analyses with the P3DASS program were helpful to predict the trend of experimental responses of a centrifuge model efficiently, even though there were some difficulties in processing analytical results and to find out unintended deficits in measured experimental data. Also nonlinear soil properties of elements in the system can be estimated adequately using an analytical program to compare them with experimental results.

• 한국추진공학회지
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• 제20권2호
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• pp.56-66
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• 2016

모델기반 FDI 과정에서 모델오차와 센서잡음은 피할 수 없으므로 견실성은 모델기반 FDI에서 매우 중요하다. 본 연구에서는 이러한 선형모델 오차 및 신호잡음으로 인하여 고장진단 과정에서 발생하는 결함판단 오류들을 비선형 NARX (Nonlinear Auto Regressive eXogenous) 모델과 칼만추정기를 적용하여 개선하는 방법을 제안하였다. 최종 고장판단은 퍼지로직을 이용하여 발생하는 오차의 추이에 대한 확률로 결정하여 순간적인 신호잡음에 강인하도록 설계하였다. 시뮬레이션을 통하여 운용 환경조건에서 엔진제어기의 고장허용에 따른 성능을 확인하였다.

• Elastomers and Composites
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• 제45권4호
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• pp.245-249
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• 2010

Much interest on the thermoplastic elastomers (TPEs) has recently been attracted in commercial fields as well as scientific and applied research. The TPEs have their own characteristic area especially in relation with block copolymers as well as many other polymeric materials, since they show interesting features displayed by the conventional vulcanized rubber, and at the same time, by the thermoplastics. In addition, they are characterized by a set of interesting properties inherent to block and graft copolymers, variety of blends and vulcanized materials. The importance of TPE as organic materials can be evaluated by the number of published reports (papers, patents, technical reports, etc). For the suitable introduction of the TPE, historic, scientific, technical and commercial considerations should be taken into account. This review article starts with a brief discussion on historical considerations, followed by a introduction of the main preparations and analytical techniques utilized in chemical, structural, and morphological studies. The properties, processing tools, the position among organic materials, and applications of TPEs are also briefly reviewed. Finally, the most probable trends of their future development are discussed in a short final remarks.

• 품질경영학회지
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• 제49권1호
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• pp.97-112
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• 2021

Purpose: The purpose of this paper is to analyze the technology convergence and its characteristics, focusing on the defense technologies in South Korea. Methods: Patents applied by the Agency for Defense Development (ADD) during 1979~2019 were utilized in this paper. Information Entropy analysis has been conducted on the patents to analyze the usability and potential for development. To analyze the trend of technology convergence in defense technologies, Social Network Analysis(SNA) and Association Rule Mining Analysis were applied to the co-occurrence networks of International Patent Classification (IPC) codes. Results: The results show that sensor, communication, and aviation technologies played a key role in recent development of defense science and technology. The co-occurrence network analysis also showed that the convergence has gradually enhanced over time, and the convergence between different technology sectors largely emerged, showing that the convergence has been diversified. Conclusion: By analyzing the patents of the defense technologies during the last 30 years, this study presents the comprehensive perspectives on trends and characteristics of technology convergence in defense industry. The results of this study are expected to be used as a guideline for decision making in the government's R&D policies in defence industry.

• 한국식품영양학회지
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• 제35권2호
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• pp.137-149
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• 2022

The purpose of this paper was to analyze domestic patents for food using edible insects. From January 1, 1980 to December 31, 2021, patents filed with the Korean Intellectual Property Office were searched, and a total of 242 valid patents were selected. The trend of Korean patent applications for edible insect food has increased since 2015, with 57 cases (the highest number) in 2017. As for the edible insects used in food, Bombyx mori L. were the most common with 127 cases, followed by Tenebrio molitor L. with 118 cases. By type of applicant, individuals accounted for the most, with 132 cases. As a result of grouping patents by food classification, 67 cases of edible insects were used in snacks, breads, and rice cakes. As a result of patent analysis, an effort was made to supplement insufficient nutrients by adding nutritionally excellent edible insects to existing foods, and efforts were made to improve the sensory properties of insect foods. It is expected that this study will contribute to establishing future R&D directions and patent application strategies related to edible insect food.

• Journal of Positioning, Navigation, and Timing
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• 제10권4호
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• pp.235-242
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• 2021

Unmanned Aerial Vehicles (UAVs), which were used for military purposes, are gradually expanding their application fields under the influence of electrification and digitalization. Starting from the field of aerial imaging and Intelligence Surveillance and Reconnaissance (ISR) mission, nowadays the possibility of Urban Air Mobility (UAM), which transports passengers and cargo with drones, is widely under discussion. In order to occupy the rapidly growing global unmanned aerial vehicle market in advance, it is necessary to secure core technologies and develop key UAVs components based on the new technologies. In the navigation field, it is necessary to secure a precise position with guaranteed reliability and continuity, unrelated to the operating environments. The reliability and continuity should be secured in the algorithm level and in the H/W component levels also. In order to achieve this technical goal, the Ministry of Science and ICT has launched the 'Unmanned Vehicle Core Technology Research and Development Program' in 2019 to support the R&D on the unmanned vehicle technologies. In this paper, authors introduce the unmanned vehicle core technology research and development program to the related researchers. The authors summarize the backgrounds of the program and show the technological tasks and objectives on the sub-programs in the unmanned vehicle navigation program. We present the program schedules especially focused on the test and evaluation of the developed technologies and components.

• 한국식품영양학회지
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• 제35권4호
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• pp.253-258
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• 2022

An increasing trend embracing the 2030 generation mindset through the new word 'newtro', which means reinterpreting the past and selling it in the present, has been gaining traction. The 2030 generation who seek new experiences and desserts is growing. The unique dessert market is expected to continue to grow in the future. Thus, this study devised a pine needle madeleine. Madeleines were made by varying the proportions of pine needle powder added to 0%, 1%, 3%, 5%, and 7%, and specific gravity, moisture, color, physical properties, and antioxidant properties were measured. The L-value decreased significantly (p<0.001) as the amount of pine needle powder added increased, and the a-value increased (p<0.001). The total polyphenol content, DPPH, and ABTS gradually increased significantly (p<0.001). Through this study, it was possible to confirm the quality and characteristics of madeleines using pine needle powder, which has excellent antioxidant properties, and it will become basic data for the development of various desserts using pine needle powder.

• 한국추진공학회지
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• 제26권6호
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• pp.74-85
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• 2022

1990년대부터 기존 맹독성 이원추진제를 대체하기 위해 수행되어 오던 친환경 혹은 저독성 이원추진제 조합에 관한 연구는 최근 우주 추진기술 개발과정에서 경제성, 안정성, 효율성 등이 강조되며 더욱 주목받고 있다. 연구활동은 주로 저독성 하이퍼골릭 연료를 개발하는 것에 집중되어 왔으며 백연질산 혹은 고농도 과산화수소 산화제로 사용하였다. 저독성 하이퍼골릭 연료의 종류는 촉매성 연료, 반응성 연료, 이온성 연료로 구분할 수 있다. 본 논문에서는 하이퍼골릭 이온성 연료의 연구개발 동향을 소개하고 선행연구에서 보고된 주요 결과들에 대해 분석하고자 한다.

• Journal of Information Technology Applications and Management
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• 제29권6호
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• pp.1-12
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• 2022

In recent years, technological competition in the automobile sector is accelerating. This study analyzes the status of patents from a global perspective of three promising future items that Korea has selected as core technologies in the field of autonomous driving,. And the technological cooperation ecosystem was identified through network analysis centered on scientific metrology. As a result of the analysis, it was confirmed that the growth of individual technologies has been strengthened in recent years, and although key source technologies have been largely preempted in major global countries, a close cooperative ecosystem between institutions, companies, and universities in major countries has not yet been formed. Specifically, the US and Japan have the technological leadership, while China is rapidly rising, and Korea is chasing after it as a latecomer. Therefore, it is necessary to continuously strengthen technological cooperation such as R&D of core technology to overcome technological limitations and strengthening of infrastructure construction, attracting excellent foreign talents and international exchanges. This analysis is meaningful in that it explores the global status of Korea's technology and the possibility of technological cooperation from various perspectives in the future from the viewpoint of preoccupation of future technology, rather than grasping the trend of a specific technology.