• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.677-680
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• 2008

본 논문에서는 다층매질 안에 위치한 안테나의 방사특성을 해석하고 있다. 접지면이 없는 유전체 기판에 인쇄된 안테나의 경우, 매질의 구성은 공기층을 포함하여 3층매질이 되며 이러한 3층매질의 Green 함수은 Sommerfeld적분식으로 표현되기 때문에 해석이 매우 복잡해진다. 그러나 안테나위 방사특성을 해석하는데 있어서는 적분식의 조건이 잘 일치한다면 Sadddle-point법을 이용하여 근사할 수 있다. 본 연구에서는 이와 같은 근사법을 적용하여 접지면이 없는 유전체 기판에 놓인 각종 안테나의 방사패턴 특성을 해석한다. 또한 기판으로 사용하는 유전체의 파라미터를 달리하여 방사특성을 검토한다.

• 한국산업융합학회 논문집
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• 제7권3호
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• pp.281-288
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• 2004

The objective of this study is to propose a methodology of the flood runoff analysis in steep mountainous basins and the analysis basin is the Jasa valley basin in Chungju city Analyzing the spatial pattern of the rainfall in 1994. 6 30~7.1, the seasonal rainy front was tied up in the whole central district, and the rainfall center was moving from the northern Chungbuk province to the northern Kyongbuk province and caused heavy storm. Analyzing the temporal pattern with the Huff method, the 52.5% of the rainfall was concentrated on the 3rd quartile. Rainfall frequency analysis is accomplished by five distribution types; 2-parameter Lognomal, 3-parameter Lognomal, Pearson Type III, Log-Pearson Type III and Extremal Type I distribution Rainfall-runoff analysis in Jasa valley basin was made using HEC-HMS model. Jasa valley basin was divided into 3 sub-basins and the analysis point was 3 points{A, B and C point) With the rainfall data measured by the 10 minutes, the flood runoff also was calculated by as many minutes. SCS CN model, Clark UH model and Muskingum routing model in HEC-HMS model were used to simulate the runoff volume using selected rainfall event.

• 대한물리치료과학회지
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• 제9권1호
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• pp.123-128
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• 2002

Objectives: The objective of this study was to investigate factor analysis of low back pain patients. Methods: The data were collected from hospital located in Daegu. Observation was made on 40 low back pain patients and factor analysis study was also performed in terms of their abnormal physical findings. Results: The low back pain patients occupied 20% of all clinical patients in male group and 20% in female group. The occurrence of acute low back pain in the first factor tended to be higher among in male group than among in female group. While it was significantly higher muscle weakness of the back in female group. The most prevailing abnormal finding among low back pain patients in the first factor were tender point on the back, While it was significantly lower Decreased tendon reflex in both sexes Conclusions: The factor pattern of abnormal physical findings in low back pain patients was much different between male and female patients, suggesting the different pattern of etiology. Although low back pain is one of the most common symptoms causing limitation activity, as yet there is no known specific effective treatment.

• Journal of Ecology and Environment
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• 제40권1호
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• pp.34-44
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• 2016

Background: Little is known about how chemical water quality is associated with ecological stream health in relation to landuse patterns in a watershed. We evaluated spatial characteristics of water quality characteristics and the ecological health of Dongjin-River basin, Korea in relation to regional landuse pattern. The ecological health was assessed by the multi-metric model of Index of Biological Integrity (IBI), and the water chemistry data were compared with values obtained from the health model. Results: Nutrient and organic matter pollution in Dongjin-River basin, Korea was influenced by land use pattern and the major point sources, so nutrients of TN and TP increased abruptly in Site 4 (Jeongeup Stream), which is directly influenced by wastewater treatment plants along with values of electric conductivity (EC), bacterial number, and sestonic chlorophyll-a. Similar results are shown in the downstream (S7) of Dongjin River. The degradation of chemical water quality in the downstream resulted in greater impairment of the ecological health, and these were also closely associated with the landuse pattern. Forest region had low nutrients (N, P), organic matter, and ionic content (as the EC), whereas urban and agricultural regions had opposite in the parameters. Linear regression analysis of the landuse (arable land; $A_L$) on chemicals indicated that values of $A_L$ had positive linear relations with TP ($R^2=0.643$, p < 0.01), TN ($R^2=0.502$, p < 0.05), BOD ($R^2=0.739$, p < 0.01), and suspended solids (SS; ($R^2=0.866$, p < 0.01), and a negative relation with TDN:TDP ratios ($R^2=0.719$, p < 0.01). Conclusions: Chemical factors were closely associated with land use pattern in the watershed, and these factors influenced the ecological health, based on the multimetric fish IBI model. Overall, the impairments of water chemistry and the ecological health in Dongjin-River basin were mainly attributes to point-sources and land-use patterns.

• 대한가정학회지
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• 제17권4호
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• pp.1-14
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• 1979

The functional problems of the basic pattern of clothing are a matter of the first importance to clothing construction. Therefore, the ergonomic analysis of the expansion and contraction of the upper body surface, due to motion, has become required. thus in order to obtain the measurements and rate of expansion and contraction of the upper body surface following from its motions, the development figure of " Shell" and somatometry were employed. The results obtained through the investigation can be summarized as follows : 1) According to the developmental figures of "Shell" the latitudes centering around the shoulder line present contractive tendencies by arm movement. The longitudes around the center back waist length are expansive tendencies when bent forward. In the case of a 15$^{\circ}$ lean backward posture, the longitudes around the center front waist length are expansive tendencies. 2) By somatometry, the region from the scapula to the axilla point the upper back with presents the greatest expansion (more than 30%). The region from scapla to arm presents the maximum rate of contraction. In considering the longitude , under the axilla waist length and the bust point waist length generally shows the greatest rate of expansion. 3) The bust point waist length and under the axilla waist length are of great importance to the basic pattern of clothing. and have expansive tendencies(6.3cm). Among the latitudes, the upper back width has the greatest tendency for expansion (7.83 cm). 4) The region which presents the greatest rate of the expansion and contraction is in the proximity of the arm. These results testify that the amount of room of the back width must be given consideration in constructing the basic pattern of clothing.pattern of clothing.

• 전력전자학회논문지
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• 제25권5호
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• pp.385-393
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• 2020

This study introduces an analysis and control method for the variation of neutral point current in a grid-tied three-level neutral point clamped (NPC) converter under various grid imbalance operating conditions. Various fault cases with unbalanced amplitude and phase are systematically categorized and described using a unified metric called the imbalance factor. The fundamental component of neutral point current is generated under grid imbalance cases. The pattern and behavior of this fundamental component of neutral point current highly depend on the imbalance factor regardless of the particular type of grid fault cases. The control scheme for regulating the negative sequential component of AC input current effectively reduces the size of the fundamental component of neutral point current under a wide range of grid imbalance cases. The control scheme will enable a grid-tied three-level NPC converter to operate reliably and stably under various types of grid faults.

• 한국물환경학회지
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• 제33권1호
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• pp.78-89
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• 2017

Water quality monitoring network data is being affected continuously due to non-point source pollution arising from agricultural land located on the Gwangsancheon outlet in the Nakdong River basin. In this study, we have performed analysis of water quality monitoring system, water quality pattern using SOM and water quality in the Gwangsancheon for sub-basin located at Gisan-myeon in the Nakdong River basin. We have developed and applied the model to estimate the runoff and non-point source loading. As a result of SOM pattern, the effect of non-point source pollution was the largest in the paddy fields and fields. As a result of the developed model, we found contribution rate and reduction rate for non-point source loading according to change of landuse because the reduction effect of nonpoint pollutants was 20.9% of SS, 9.9% of TN, 21.2% of TP and 8.9% of TOC depending on the landuse change.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2005년도 종합학술대회
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• pp.147-153
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• 2005

최근 인터넷 쇼핑몰에서 상품을 구매하는 고객들에게 편의성과 효율성을 제공하기 위하여 구매자들의 선호도나 가격에 맞는 상품을 추천해 주는 연구들이 활발하게 진행되고 있지만추천된 상품들의 구매시점에 관한 연구는 찾아보기 어렵다. 이에 본 논문에서는 인터넷 쇼핑몰의 적극적인 마케팅 일환으로 판매가격의 흐름을 시계열 패턴으로 분석하여 상품의 구매시점 정보를 제공하는 방안을 제안한다. 이를 위하여 과거의 판매 기록 데이터베이스에 있는 판매가격의 기준이 되는 패턴과 유사한 변화를 보이는 패턴을 정규화된 유사도로써 검색하고, 검색된 가격 패턴을 기준으로 미래의 가격 패턴의 변화를 분석하여, 미래 가격 패턴의 변화 폭에 따라 상품에 대한 구매시점을 제공한다.

• 패션비즈니스
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• 제15권5호
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• pp.178-194
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• 2011

Due to the population growth of the old aged, Korea is also entering into an aging society. But a research on the pattern design to the old aged is much to be desired. The purpose of this research is to design skirt pattern fitted for each body type by categorizing the lower body type of the old aged woman. For the way of research, categorized the body type by using the female measuring size from the 65 years old to 99 years old which has been measured by the Korean body size research as an assay data, and base on this data, a suitable skirt pattern for each body type of the old aged woman was designed by practicing the exterior evaluation. The data analysis was done with the statistical treatment in SPSS 12.0, and the results are as follows. The lower body type of the old aged woman were divided into the type 1. The circumference article is the biggest compared to the height article regarding to the lower body type of the old aged woman. The type 2. The height article and the circumference and thickness articles are the poorest. The type 3. The height article is the biggest and the hip width and calf circumference are thicker than the waist width. The type 4. The height article is the lowest and the waist width is thicker instead the hip and leg are thinner. In type 1, The pattern was modified by increasing 1cm a length of the dart and raising up 1.2cm at the cross point between side line and waist line. In type 2, the basic pattern was used, and in type 3, using the outline of the basic pattern however, increased 1cm a length of the dart and modified the amounts of dart by handling the art in curve, and modified the waist line to be more three-dimensional curves by raising up 1 cm at the cross point between waist line and side line and falling down 0.5cm at the cross point between the back center line and the waist line. In type 4, modified the amounts of front and back dart to 1.25cm, and raised up 0.8cm at the cross point between side line and waist line, and modified the waist line and the side seam line in a gentle curve by reducing circumference of the skirt tail to 1cm from the side seam line.

• International Journal of Aeronautical and Space Sciences
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• 제10권2호
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• pp.86-94
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• 2009

This paper deals with the creation of a new, low-cost point/position tracking system that can measure deformations in engineering structures with simple commercially widespread cameras. Though point tracking systems do exist today, such as Stereo Pattern Recognition (SPR) and Projection Moir$\acute{e}$ Interferometry (PMI) systems, they are far too costly to use to analyze small, simple structures because complex optical components such as large flashes, high-resolution cameras and data acquisition systems with several computers are required. We developed a point tracking system using commercial cameras. This system used IR LEDs and commercial IR CCD cameras to minimize the interference posed by other extraneous light sources. The main algorithm used for this system is an optical point tracking algorithm, which is composed of the point extraction algorithm and the point matching algorithm for 3-D motion estimation. a series of verification tests were performed. Then, the developed point tracking system was applied to measure deformations of an acrylic plate under a mechanical load. The measured deformations of the acrylic plate matched well with the numerical analysis results. The results indicate that the developed point tracking system is reliable enough to measure continuous deformed shapes of various engineering structures.