• 대한의용생체공학회:의공학회지
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• 제35권3호
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• pp.35-41
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• 2014

In this study, joint angles of the lower extremity and inertial sensor data such as accelerations and angular velocities were measured during a ski simulator exercise in order to evaluate the skill of skiers. Twenty experts and twenty unskilled skiers were recruited for the study. All expert skiers held the certificates issued by the Korea Ski Instructors Association. A three-dimensional motion capture system and two inertial sensors were used to acquire joint movements, heel acceleration and heel angular velocity during ski simulator exercises. Pattern variation values were calculated to assess the variations in ski simulator motion of expert and unskilled skiers. Integral ratio of roll angular velocity was calculated to determine the parallel alignment of the two feet. Results showed that ski experts showed greater range of motion of joint angle, peak-to-peak amplitude(PPA) of heel acceleration and PPA of heel angular velocity than unskilled skiers. Ski experts showed smaller pattern variations than unskilled skiers. In addition, the integral ratio of roll angular velocity in ski experts was closer to 1. Inertial sensor data measurements during the ski simulator exercises could be useful to evaluate the skill of the skier.

• 융합정보논문지
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• 제10권7호
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• pp.108-115
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• 2020

본 연구의 목적은 중년(45~64세) 남녀를 대상으로 주관적 사회계층과 자살생각의 관계에서 자아존중감과 사회적 지지의 이중 매개효과를 파악하는 것이다. 대상자의 주관적 사회계층이 자살생각에 영향에 사회적 지지와 자아존중감의 매개효과를 확인하기 위해 병렬 이중 매개모형으로 분석하였다. 성별, 연령, 동거인 여부와 우울을 보정한 상태에서 독립변수인 주관적 사회계층은 매개변수인 사회적 지지(β =0.23, p<.001)와 자아존중감(β =0.12, p <.001)에 사회적 지지는 자아존중감에 유의한 영향을 미쳤다(β =0.21, p<.001). 종속변수인 자살생각에 주관적 사회계층(β =-0.25, p<.001), 사회적 지지(β =-0.32, p<.001)와 자아존중감(β =-0.19, p=.001)이 모두 통계적으로 유의한 영향을 미쳤다. 주관적 사회계층이 자아존중감을 매개로 하여 자살생각에 미치는 간접효과와 주관적 계층이 사회적 지지 그리고 자아존중감을 거쳐 자살생각에 이르는 다중 간접효과 모두 유의하였다. 본 연구의 결과에 따라 중년성인을 대상으로 생활터 기반의 사회적 지지체계 구축이 필요하다. 이는 중년성인의 자아존중감 향상에 기여하여, 자살예방에 긍정적 영향을 미칠 것이다.

• 제어로봇시스템학회논문지
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• 제16권3호
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• pp.305-312
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• 2010

The aim of this study is to find an analytic solution to the problem of determining the optimal capacity of a batch-storage network to meet demand for finished products in a system undergoing joint random variations of operating time and batch material loss. The superstructure of the plant considered here consists of a network of serially and/or parallel interlinked batch processes and storage units. The production processes transform a set of feedstock materials into another set of products with constant conversion factors. The final product demand flow is susceptible to joint random variations in the cycle time and batch size. The production processes have also joint random variations in cycle time and product quantity. The spoiled materials are treated through regeneration or waste disposal processes. The objective function of the optimization is minimizing the total cost, which is composed of setup and inventory holding costs as well as the capital costs of constructing processes and storage units. A novel production and inventory analysis the PSW (Periodic Square Wave) model, provides a judicious graphical method to find the upper and lower bounds of random flows. The advantage of this model is that it provides a set of simple analytic solutions while also maintaining a realistic description of the random material flows between processes and storage units; as a consequence of these analytic solutions, the computation burden is significantly reduced. The proposed method has the potential to rapidly provide very useful data on which to base investment decisions during the early plant design stage. It should be of particular use when these decisions must be made in a highly uncertain business environment.

• 한국중재학회지:중재연구
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• 제14권1호
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• pp.133-156
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• 2004

The rapid development of the internet may not have occurred without techniques of linking and framing, which provide users flexible and easy access to other website. These techniques have enabled internet users to navigate the internet efficiently and sort through the products, services and information available on the internet. The Advent of the global information structure and the do-called EC revolution raise countless new issues and questions. There are no limitations regulating the expressions on the cyberspace due to internet's of quality anonymity? diversity? spontaneity. Therefore, the freedom of speech is expanded in both areas of time and space, which was impossible with the old communicating system. Although online technology raises many new legal issues, the law available to help us resolve them, at least today, is largely based on the world as it existed before online commerce became a reality. Thus the challenge is to predict how these new legal issues may be resolved using the current law. As a result of the drastic change of the environment for international trade of which that has taken took place in parallel with the global information technology revolution on a global basis, the scope of issues to be addressed which should be resolved by the conflict of laws principles has been remarkably expanded, and various new issues of an entirely which are quite new in its type and nature have arisen been raised. Further more in addition, the old act prior act was regarded as insufficient in that it lacked rules on international governing law to adjudicate, or international adjudicatory governing law, where as the expectation of the public was that the private international law should function as the basic law of the legal relational encompassing rules on governing law given the increase of It international disputes. for the move the private international law has also attracted more attention from the korean.

• 대한전자공학회논문지TC
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• 제42권10호
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• pp.17-24
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• 2005

본 논문에서는 극수의 순환성을 이용하여 GF(3)상에서 새로운 GRM(Generalized Reed-Muler:GRM)상수를 생성 하는 방법을 제안하였다. 일반적인 GRM 상수의 생성 방법은 RM 변환을 이용하여 고정 극수 p = 0의 GRM상수를 구한 후, 이를 확장하여 모든 극수의 GRM 상수를 구하는 것이다. 이 방법은 변수의 개수가 증가함에 따라 적용되는 변환 행렬의 차수도 커지게 되므로 연산자의 숫자도 증가하게 된다. 이에 반해, 본 논문에서 제시한 방법은 극수의 순환성을 이용하여 순차적으로 상수를 생성하는 방법으로서 연산식이 가장 간단한 특정 극수의 변환 방식을 반복 적용, GRM 상수를 생성하여 병렬형의 출력을 갖는 GRM 상수 생성 방법보다 상수 생성과정에 있어서 비교적 간단하고 연산자의 수도 감소하였다. 기존에 발표된 직 $\cdot$ 병렬형의 연산 방법에 비하여 하드웨어 적인 측면에서 승산기의 사용을 제한하고 가산기만을 사용하므로 효율적인 회로 구성과 함께 시스템의 복잡도를 개선할 수 있다.

• 전자공학회논문지
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• 제53권1호
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• pp.153-158
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• 2016

본 논문에서는 집중호우, 태풍, 허리케인과 같은 자연재해로 인한 낙과된 배 봉지를 자동으로 검출할 수 있는 알고리즘을 구현하였다. 검출 대상인 배 봉지는 글자가 인쇄된 회색 계열로, 수출용 배를 대량으로 생산하는 상주와 나주의 대규모 농원들에서 주로 사용한다. 제안한 알고리즘은 먼저 영상에서 관심영역을 설정하고, 설정한 관심 영역에 대해 유채색 영역을 제거한 후 형태학적 연산을 사용하여 잡음이나 이상 영역을 제거하여 낙과 영역을 검출한다. 이 낙과 영역을 분석하고 계수하여 낙과 피해 규모를 산정한다. 실험영상으로는 2014년 상주와 나주 배농원에서 촬영한 영상을 사용하였다. 제안한 기법은 실험영상에 대해 90% 이상의 검출 성능을 얻었으며, 알고리즘 구성이 간단해서 실시간 하드웨어 적용 및 모바일 디바이스를 활용한 구현도 가능하다.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1429-1435
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• 2012

태양광 시스템이나 연료전지 시스템 그리고 전기자동차에 많이 사용되는 DC-DC 컨버터는 부스트 컨버터이다. 이러한 부스트 컨버터를 병렬로 연결하고 위상차를 두고 동작하여 입출력 전류리플을 줄이는 인터리브드 부스트 컨버터가 최근에 많이 사용되고 있다. 이 회로는 입출력 전류 리플이 작기 때문에 입출력 커패시터의 크기를 줄일 수 있다. 따라서 기존의 전해 커패시터를 신뢰성이 우수한 필름 커패시터로 교체할 수 있고 이는 전체 시스템의 수명 및 신뢰성을 향상시킬 수 있다. 본 논문에서는 다단 인터리브드 부스트 컨버터에 사용되는 출력 커패시터의 전류리플 수식을 유도하고 듀티에 따른 특성을 알아본다. 이를 확인하기 위해서 PSIM 툴을 이용하여 계산된 값과 비교를 할 것이다.

• 지능정보연구
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• 제4권1호
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• pp.133-147
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• 1998

Recently, many researchers have been involved in finding deterministic equations which can accurately predict future event, based on chaotic theory, or fractal theory. The theory says that some events which seem very random but internally deterministic can be accurately predicted by fractal equations. In contrast to the conventional methods, such as AR model, MA, model, or ARIMA model, the fractal equation attempts to discover a deterministic order inherent in time series data set. In discovering deterministic order, researchers have found that neural networks are much more effective than the conventional statistical models. Even though prediction accuracy of the network can be different depending on the topological structure and modification of the algorithms, many researchers asserted that the neural network systems outperforms other systems, because of non-linear behaviour of the network models, mechanisms of massive parallel processing, generalization capability based on adaptive learning. However, recent survey shows that prediction accuracy of the forecasting models can be determined by the model structure and data structures. In the experiments based on actual economic data sets, it was found that the prediction accuracy of the neural network model is similar to the performance level of the conventional forecasting model. Especially, for the data set which is deterministically chaotic, the AR model, a conventional statistical model, was not significantly different from the MLP model, a neural network model. This result shows that the forecasting model. This result shows that the forecasting model a, pp.opriate to a prediction task should be selected based on characteristics of the time series data set. Analysis of the characteristics of the data set was performed by fractal analysis, measurement of Hurst index, and measurement of Lyapunov exponents. As a conclusion, a significant difference was not found in forecasting future events for the time series data which is deterministically chaotic, between a conventional forecasting model and a typical neural network model.

• 전기학회논문지P
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• 제63권4호
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• pp.361-367
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• 2014

This paper is related to a new solar power conditioner for a built-in step-up chopper function. In the first step-up chopper proposed solar PV power conditioner for mutually connected in series with the input voltage of the bypass diodes are respectively connected to the positive terminal should install the mutual boosting chopper diode connected in series with the boost chopper switching element between the two power supply and at the same time the first and the second was connected to a second diode and a resonance inductor and a snubber capacitor in series with each other. And the common connection point between the bypass diode and the step-up chopper and the step-up chopper diode common connection point of the switching elements of the input voltage was set to the boost inductor for storing energy. In addition, between the step-up chopper and the step-up chopper diode and a switching element of a joint connection point of the first auxiliary diode and the second common connection point of the auxiliary diode was provided, the resonance capacitor. Between the step-up chopper and the step-up chopper diode and a switching element of a joint connection point and the common connection point of the resonance inductor snubber capacitor and connecting the third secondary diode, between two power supply lines is characterized by configuring the DC link capacitor bus lines in parallel. Therefore, it is possible to suppress the switching loss through, DC link bus lines, as well as there could seek miniaturization and weight reduction of the power conditioner itself by using a common capacitor of the non-polar non-polar electrolytic capacitor having a capacitor, the service life of the circuit can be extended and it is possible to greatly reduce the loss can be greatly improve the reliability of the product and the operation of the product itself.

• 대한공업교육학회지
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• 제31권1호
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• pp.185-199
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• 2006

본 연구에서는 구조물이 횡방향으로 음압을 받을 경우 이를 감지하기 위하여 Fabry-Perot형 광섬유 배열 센서를 제작하고 실험하였다. 이는 한 개의 광원으로 두 개의 센서가 병렬로 연결되고 센서의 출력신호를 보기 위한 별도의 신호처리기가 필요 없는 구조이다. 횡방향 음압을 임의의 음원 주파수인 100Hz, 200Hz 및 655Hz의 주파수를 무지향성 스피커에 인가하였으며 $60cm{\times}60cm{\times}60cm$의 격자 구조물에 부착된 두 개의 배열 센서가 잡은 신호를 분석하였다. 시간 영역에서 두 개의 센서 신호는 진폭에 약간의 차이는 있으나 음원 주파수를 잘 감지함을 확인 하였다. 센서가 실제로 양단이 지지된 구조의 배열 센서를 모델링하고 그 해를 실험결과와 비교하였다. 2kHz의 음원을 배열 센서에 인가하였더니 이론 해석과 비교적 잘 일치하는 측정 결과를 얻었다.