• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.341-346
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• 2005

Nowadays, adsorption chillers have been receiving considerable attentions as they are energy-saving and environmental1y benign systems. A Fin & tube type heat exchanger in which adsorption/desorption take place is required more compact size. The adsorption chiller is expected to have high energy-efficiency in utilizing the waste heat exhausted from a process. The objectives of this paper are to investigate the effect of fin pitch of fin & tube on the adsorption performance and to develop an optimal design fin & tube heat exchanger in the silica gel/water adsorption chiller. Previous study concluded that optimal particle size selected 0.5mm, type HO silica gel, and fundamental heat transfer & mass transfer experiments carried out. From the numerical results, the adsorption rate for the fin pitch 2.5mm is the highest than that for the fin pitch 5mm, 7.5mm and 10mm. Also cooling water & hot water temperature affect the adsorption rate.

• 경영과정보연구
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• 제36권5호
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• pp.195-222
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• 2017

오늘날의 경제는 모든 영역의 경계가 허물어짐에 따라 서로 다른 산업 간의 융복합화가 활발해지며 이는 모바일, 소셜 네트워크 서비스 등의 혁신을 이루어내고 있다. 이러한 기술혁명가운데 모바일과 인터넷의 장점을 결합하여 금융과 IT의 업무를 손쉽게 처리할 수 있는 오늘날 새로운 기술을 핀테크라 하며 이러한 핀테크는 금융을 의미하는 파이낸스(Finance)와 기술을 의미하는 테크놀로지(Technology)의 합성어이다. 이에 본 연구는 핀테크 이용 동기(유용성, 즐거움)가 이용자 태도, 구전의도에 미치는 영향의 전반적인 구조적 관계에 대하여 살펴보았다. 이와 더불어 혁신저항 성향에 따라 핀테크 이용 동기, 이용자 태도, 구전 의도는 어떻게 달라지는지 살펴보았다. 또한, 메시지 유형(이성적, 감성적)에 따라 핀테크 이용 동기, 이용자 태도, 구전 의도는 어떻게 달라지는지 살펴보았다. 한편, 본 연구의 주요결과는 다음과 같다. 첫째로, 핀테크 이용 동기요인의 유용성과 즐거움은 사용자태도에 긍정적인 영향을 미치는 것으로 나타났으며 이용자 태도 또한 구전의도에 긍정적인 영향을 미치는 것으로 나타났다. 둘째로, 핀테크 이용 동기, 이용자 태도, 구전의도간의 관계는 소비자들의 혁신저항에 따라 차이가 나는 것으로 밝혀졌다. 셋째로, 핀테크 이용 동기, 이용자 태도, 구전의도간의 관계는 메시지 유형(이성적, 감성적)에 따라 차이가 나는 것으로 밝혀졌다. 연구의 결론 부분에서는 연구결과의 요약, 시사점 및 한계점, 그리고 향후 연구방향에 대해서 기술하였다.

• 제어로봇시스템학회논문지
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• 제10권7호
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• pp.658-668
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• 2004

This paper is concerned with a control allocation strategy using the dynamic inversion and the pseudo inverse control which generates the nominal control input trajectories. In addition, an autopilot design method is proposed by using time-varying control technique which is time-varying version of the pole placement of linear time-invariant system for an agile missile with aerodynamic fin and thrust vectoring control. The control allocation proposed in this paper is capable of extracting the maximum performance by combining each control effector, aerodynamic fin and thrust vectoring control. The adopted time-varying control technique for the autopilot design enhances the robustness of the tracking performance for a reference command. The main results are validated through the nonlinear simulations with aerodynamic data.

• 제어로봇시스템학회논문지
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• 제10권10호
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• pp.947-955
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• 2004

This paper is concerned with a mixed control with aerodynamic fin and side thrust control applied to an agile missile using a dynamic inversion and a time-varying control technique. The nonlinear dynamic inversion method with the weighting function allocates the desired control inputs(aerodynamic fin and side thrust control) to achieve a reference command, and the time-varying control technique plays the role to guarantee the robustness for the uncertainties. The proposed schemes are validated by nonlinear simulations with aerodynamic data.

• 제어로봇시스템학회논문지
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• 제6권1호
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• pp.91-97
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• 2000

In this paper, the illuminator is designed to recognize the shape and the existence of holes of radiation fin in the point that the light reflection characteristics are different according to the roughness of the material. The threshold value, the positions of holes and the black pixel nembers in the positon are obtained under the illuminator, in accordance with the reference image, by applying binary conversion and hole segmentation algorithm, as they are suggested in this paper, The existence and shape of hole are recognized by calculating the distance and feature value in the test image, which is obtained from the parameters of reference image. It is programmed to apply to GUI(Graphic User the Interface) in windows. More than 98% of recognition rate is shown, as it is applied to three different sizes of the radiation fin.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.508-513
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• 2003

This paper is concerned with a mixed control with aerodynamic fin and side thrusters applied to an agile missile using two-time scale dynamic inversion and linear time-varying control technique. The nonlinear dynamic inversion method with the weighting function allocates the desired control inputs (aerodynamic fin and side thrusters) to track a reference trajectory, and the time-varying control technique guarantees the robustness for the uncertainties. Closed-loop stability is achieved by the assignment of the extended-mean of these linear time-varying eigenvalues to the left half complex plane. The proposed schemes are validated by nonlinear simulations.

• 전자공학회논문지
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• 제50권9호
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• pp.46-51
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• 2013

본 논문에는 무인항공기에 장착된 UHF 안테나의 최적 위치 및 형상이 다양한 위치에서 EM 시뮬레이션을 통하여 분석되어져 있다. EM 시뮬레이션을 위하여 FEKO를 이용하였다. 시뮬레이션의 복잡도를 줄이고 분석시간과 메모리 이용도를 최소화하기 위하여 비행체의 복합체 구조를 레이돔 구조를 제외하고 PEC 모델로 간략화 하였다. 시뮬레이션은 무인항공기의 날개와 Ventral Fin 위치에서 수행되어 졌고, 안테나 형상은 모노폴, 다이폴, 굴곡형 모노폴 안테나들을 이용하였다. 모노폴 안테나가 비행체 날개에 장착될 경우, 오른쪽 날개와 왼쪽 날개에 각각 장착되어지기 위하여 두 개의 안테나가 필요하고, 이 두 개의 안테나들은 가시선 데이터링크 지상 안테나에 대한 무인항공기 날개 방향에 따라 전환되어져야 한다. 모노폴 안테나가 Ventral Fin에 장착될 경우, 가시선 데이터링크 지상 안테나에 대한 무인항공기 날개 방향에 상관없이 하나의 안테나로 운용 가능하다. 또한, 안테나 이득도 비행체에 의한 Blockage 감소로 개선되어진다. 안테나 이득은 굴곡형 모노폴 안테나를 이용하여 더욱 더 개선되어 진다. 결론적으로 무인항공기에 장착된 UHF 안테나의 최적 위치 및 형상은 굴곡형 모노폴 안테나를 Ventral Fin 아래에 장착하는 것이다.

• 유통과학연구
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• 제21권5호
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• pp.113-120
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• 2023

Purpose: The purpose of the study is to examine how payment systems for traditional distribution channels pursue changes and how they collaborate in-depth with fintech companies. This study examines the changing payment system through the strategic partnership between distribution companies and fintech companies. Research Design, Data and Methodology: The study conducted research using a variety of secondary materials and existing literature and also utilized the interview method. More specific and in-depth research is conducted through various literature studies and secondary data. Findings and Results: The findings of the study are as follows. First, distributors have occasionally directly adopted simple payment systems due to changes in payment systems as a result of online advances. Second, distributors were found to collaborate with fintech companies when not directly using simple payment. Conclusions: Such maneuvers by distributors are aimed at first, providing convenience and simplicity for consumers. Second, developing the ability to apply big data for accumulating consumer information and third, producing a customer lock-in effect by reducing the fees charged for existing payment services. The present study will provide many domestic and international distributors with a new perspective and practical implications in terms of the distribution and finance industries.

• 제어로봇시스템학회논문지
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• 제18권2호
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• pp.103-109
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• 2012

Fish generates large thrust through an oscillating motion with a compliant joint of caudal fin. The compliance of caudal fin affects the thrust generated by the fish. Due to the flexibility of the fish, the fish can generate a travelling wave motion which is known to increase the efficiency of the fish. However, a detailed research on the relationship between the flexible joint and the thrust generation is needed. In this paper, the compliant joint of a caudal fin is implemented in the driving mechanism of a robotic fish. By varying the driving frequency and stiffness of the compliant joint, the relationship between the thrust generation and the stiffness of the flexible joint is investigated. In general, as the frequency increases, the thrust increases. When higher driving frequency is applied, higher stiffness of the flexible joint is needed to maximize the thrust. The bending angles between the compliant joint and the caudal fin are compared with the changes of the thrust in one cycle. This result can be used to design the robotic fish which can be operated at the maximum thrust condition using the appropriate stiffness of the compliant joint.

• International Journal of Ocean System Engineering
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• 제3권1호
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• pp.10-15
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• 2013

A ship cruising in the ocean oscillates continuously due to wave action. In order to reduce the ship's roll, we developed a fin stabilizer as an anti-rolling device for a 500-ton-class high-speed marine vessel. During the development phase, it was necessary to set up control gains for the motion and hydraulic systems and assess the effectiveness of the anti-rolling performance on the ground. For this reason, a Target Simulator, which simulated the ship's motion, was given operator inputs such as the engine telegraph and waterjet deflection angle, and generated roll using a one-degree-of-freedom motion base. Hardware-In-the-Loop Simulation (HILS) was performed using the Target Simulator in order to confirm the various logics of the developed fin stabilizer, select initial control gains, and estimate the anti-rolling performance. In conclusion, it was confirmed that HILS was very helpful to develop the fin stabilizer because it could reduce the number of sea trial tests that were needed and could find many malfunctions in the factory a priori.