• 한국분무공학회지
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• 제2권2호
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• pp.16-23
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• 1997

In this research a novel two-reference-beam double pulse holographic technique for the measurments of particle sizes and velocities was developed. This holographic method features the capability of separation of the first and second particle images by using two reference beams instead of one and the change of the polarization direction of laser light. The developed holographic system was tested through the measurements of droplet sizes and velocities in the spray created by two high speed impinging jets. The overall spray pattern clearly revealed the inherent wave nature. Smaller and faster droplets were generated with larger impingement angle, higher jet velocity. and smaller orifice diameter.

• 전력전자학회논문지
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• 제18권5호
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• pp.422-428
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• 2013

Recently, we use a static synchronous compensator(STATCOM) with cascaded H-bride topologies, because it is easy to increase capacity and to reduce total harmonic distortion(THD). When we use equipment for reactive power compensation, dc-link voltage unbalances occur from several reasons although loads are balanced. In the past, switching pattern change of single phase inverter and reference voltage magnitude change of inverter equipped with power sensor have been used for dc-link voltage balance. But previous methods are more complicated and expensive because of additional component costs. Therefore, this paper explains reasons of dc-link voltage unbalance and proposes solution. This solution is complex method that is composed of reference voltage magnitude change of inverter without additional hardware and shifted phase angle of inverter reference voltages change. It proves possibility through 1000[KVA] system simulation.

• 대한전기학회논문지:전력기술부문A
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• 제48권12호
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• pp.1544-1553
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• 1999

Recently, ultrasonic testing techniques have been widely used in the evaluation of the quality of metal. In this experiment, six heat-treated temperature of specimen have been considered : 0, 1200, 1250, 1300, 1350 and 1387$^{\circ}C$. As heat-treated temperature increases, the grain size of stainless steel also increases and then, eventually make it destroy. In this paper, a pattern recognition method is proposed to identify the heat-treated temperature of metals by evidence accumulation based on artificial intelligence with multiple feature parameters; difference absolute mean value(DAMV), variance(VAR), mean frequency(MEANF), auto regressive model coefficient(ARC), linear cepstrum coefficient(LCC) and adaptive cepstrum vector(ACV). The grain signal pattern recognition is carried out through the evidence accumulation procedure using the distances measured with reference parameters. Especially ACV is superior to the other parameters. The results (96% successful pattern classification) are presented to support the feasibility of the suggested approach for ultrasonic grain signal pattern recognition.

• 한국실내디자인학회논문집
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• 제17권6호
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• pp.137-142
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• 2008

Since mid 1990s, the domestic market in Korea has been changing drastically especially in the field of discount stores. The competition among this market is more severe and the consuming pattern is also changed. This study is to examine the correlation between the customer's circulation and the spatial configuration by using Space Syntax and VMD pattern through the MD plan of each floor in Discount store. Throughout this study, it tries to find out the Quantitative analysis among three factors - the customer's circulation, spatial configuration and VMD investigation. The pattern of customer's circulation appears differently according to the identity of customer and store layout, but with the result, customer's circulation system is in accordance with the floor layout in the store. In result of the study, the circulation of the customer was found to have a close relationship with spatial structure that is composed by the MD pattern in a discount store in the area of food section. Also, the circulation system in the rest area except food section is more affected by the VMD pattern rather than spatial structure.

• 복식문화연구
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• 제27권6호
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• pp.599-614
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• 2019

The aim of this study to provide basic reference data for the development of video contents used in pattern drafting education and to explore the possibility of utilizing YouTube videos in such education. Subject videos were selected using the number of views. A total of 596 videos and 28 channels were analyzed for the period July to September 2019 and the results are as follows. With regard to content, there were 27 pattern drafting items, the majority being dress, pants, skirt, blouse and sleeve drafting, although high-level content such as cowl, bustier, corset patterns were also available. Therefore, there is a high likelihood that YouTube videos could be used as educational material, especially as supplementary references to provide specific examples and easy explanations for difficult concepts or method, for students majoring in this field. However, as most videos currently focus on a few items, expanding video content to features a wider variety of clothing items at different levels is necessary. With regard to video length, it mostly ranged from 10 to 15 minutes. It is not advisable to create lengthy lecture-style videos expounding on different principles or variations in pattern drafting when developing educational video material.

• Journal of Obesity & Metabolic Syndrome
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• 제27권4호
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• pp.254-261
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• 2018

Background: The most beneficial dietary pattern in managing metabolic syndrome (MetS) in the elderly has not been ascertained. The aim of this study is to classify dietary patterns and to examine associations between dietary pattern, MetS and body composition in elderly Koreans. Methods: This study was conducted among Koreans 65 years or older using data from the Korea National Health and Nutrition Examination Survey in 2009. A total of 1,567 study subjects were included. All statistical analyses were conducted using SPSS version 20.0 and dietary patterns were classified by cluster analysis. Results: There were three dietary patterns derived by cluster analysis in this study. We observed that most South Korean elderly still maintain a traditional dietary pattern. Dietary patterns were classified as balanced (31%), imbalanced (40%), or very imbalanced (30%), with the majority of subjects having an unbalanced diet pattern in which their total energy and nutrient intake was insufficient compared with the Dietary Reference Intake for Koreans. Those in the very imbalanced group had a ratio of macronutrients (carbohydrates:fats:protein) of 81.15:7.18:11.50 and a 54% higher likelihood of having hypertriglyceridemia (P=0.025) compared with those in the balanced group. Conclusion: The current findings indicate that the diets of South Korean elderly are nutritionally imbalanced, including high carbohydrate consumption, which confers a high risk hypertriglyceridemia. These findings highlight the effect of nutritional imbalance in elderly with MetS.

• 전기전자학회논문지
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• 제23권1호
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• pp.164-172
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• 2019

현재 배뇨 장애를 진단할 수 있는 대표적인 임상 방법들은 침습적이고 고가이며, 장시간 연속적인 모니터링을 수행하기에는 한계가 있다. EIT는 비침습적 방법으로 외부 전극을 통하여 전류를 주입하고 유기된 전압을 측정하여 내부 전기적(임피던스) 특성을 영상화 하는 기술로써, 저렴한 비용으로 방광의 상태를 모니터링 할 수 있는 유용한 기법이 될 수 있다. 전극을 통하여 주입된 전류 패턴에 따라 측정전압 데이터의 신호특성이 달라지고 영상 복원 성능에 영향을 미친다. 본 논문에서는 인체 하복부 부근에 위치한 방광의 크기 변화에 대한 민감도가 극대화될 수 있는 모델링을 위해 입력전류 패턴에 따른 영상 복원 성능을 분석하였다.

• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4751-4758
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• 2022

Two-phase flow may almost exist in every branch of the energy industry. For the corresponding engineering design, it is very essential and crucial to monitor flow patterns and their transitions accurately. With the high-speed development and success of deep learning based on convolutional neural network (CNN), the study of flow pattern identification recently almost focused on this methodology. Additionally, the photographing technique has attractive implementation features as well, since it is normally considerably less expensive than other techniques. The development of such a two-phase flow pattern online monitoring system is the objective of this work, which seldom studied before. The ongoing preliminary engineering design (including hardware and software) of the system are introduced. The flow pattern identification method based on CNNs and transfer learning was discussed in detail. Several potential CNN candidates such as ALexNet, VggNet16 and ResNets were introduced and compared with each other based on a flow pattern dataset. According to the results, ResNet50 is the most promising CNN network for the system owing to its high precision, fast classification and strong robustness. This work can be a reference for the online monitoring system design in the energy system.

• 한국소프트웨어감정평가학회 논문지
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• 제8권2호
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• pp.13-27
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• 2012

본 연구에서는 트리패턴 기반으로 코드클론을 탐지하는 도구인 CCR(Code Clone Ransacker)를 제안하고 구현하였다. CCR은 프로그램 트리의 모든 하위트리 쌍을 비교하여 중복된 부분인 트리패턴을 찾고 동일한 모양의 패턴들을 하나로 묶어 프로그램에 존재하는 클론들을 샅샅이 탐지한다. 이때 이미 찾은 패턴 내부의 클론 패턴을 비교대상에서 제외하여 중복계산을 하지 않아 불필요한 예산을 최대한 줄인다. 실험으로 CCR의 성능을 평가한 결과, CCR의 정확성과 탐지성은 높다. 프로그램의 구조를 비교하는 기존의 트리패턴 기반의 코드클론 탐지 도구들의 정확성과 탐지성은 이미 좋은 것으로 알려져 있지만, CCR은 높은 정확성을 유지하면서 탐지성은 기존의 Asta보다는 최대 5배, CloneDigger보다는 약 1.9배 높다. 그리고 CCR이 찾은 코드클론은 기존의 코드클론 표본 집합체의 클론을 대부분 포함한다.

• 대한예방한의학회지
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• 제20권2호
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• pp.17-26
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• 2016

Objectives : We presented the results of reliability study in advance, and analyzed agreement between Korean medicine doctors(KMDs)' diagnosis and cold-heat pattern identification questionnaire(CHPI)'s diagnosis. Methods : This survey was conducted from May 16 to 17, 2015. The subjects were 93 adults living in rural society. Diagnosis of CHPI was performed by 2 KMDs who have clinical experience more than 5 years. The KMDs' diagnosis was set as a reference index, and then we compare 23 items(cold pattern 11 items and heat pattern 12 items) of CHPI questionnaire and 15 items(cold pattern 8 items and heat pattern 7 items) that were brief form of it. We had cut-off value by standard of KMDs' diagnosis using receiver operating characteristic-curve(ROC-curve), with which we calculated agreement including kappa value. Correlation analysis between CHPI evaluation score by KMDs and by the questionnaire was fulfilled as well. Results : Agreement about 11 and 8 cold pattern items showed 87.1% together, and the value of kappa each recorded 0.742 and 0.741. Agreement about 12 and 7 heat pattern items suggested 81.7% and 78.5%, and the value of kappa showed 0.634 and 0.570. Correlation coefficients were 0.803 of 11 items and 0.761 of 8 items about cold pattern. In addition, correlation coefficients were 0.789 of 12 items and 0.767 of 7 items about heat pattern. The significant probability (p-value) was under 0.001. Conclusions : We have developed CHPI questionnaire involving reliability and agreement based on usual symptoms, and hope additional complements so that Korean medicine diagnostics and Korean preventive medicine would be improved.