• The Korean Journal of Ecology
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• 제22권2호
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• pp.69-77
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• 1999

Secondary vegetation. the holistically integrated system of nature and human being, is the complicated ecosystem that is composed of natural and man-created factors. Understanding the ecological function of secondary vegetation supplies us many important informations for sustainable landscape management and ecological restoration planning. In this research, we tried to examine the shape effect of vegetation patch on early structure of populations of pine and oaks. Moreover. we also tried to clarify the ecological functions of patch edge by exploring the patch effect on germination using patch index. In addition, we present the landscape structure of man -made vegetation of our study area, and setting experimental design of research. Vegetation landscape of study area is typical human disturbed landscape mainly composed of disturbance patches. Vegetation types of graveyard and managed pine forest were controlled by periodically repeated management. However, current seedlings of pine occurred well at both vegetation types. Presence of both saplings were more controlled in managed pine forest (PDM) and graveyard (G) than those of undergrowth (PD) and forest edge (FE) with canopy trees. The number of pine seedlings increased with patch size and patch perimeter. That of oak seedlings was, however, not significantly different. Larger graveyards provided higher light availability for germination of pine seedlings. We think, however, most seedlings of both species in the large sized graveyards without shade will die more easily than that of small sized ones before rainy summer. Relationships between patch shape and germination of two woody species cannot be exactly explained enough yet in these results. More informations on spatial interaction of the total species with differently sized patches are necessary to solve the concept of patch effect on species colonization.

• Weed & Turfgrass Science
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• 제4권2호
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• pp.124-128
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• 2015

갈색퍼짐병은 토양 병원성균으로 Rhizoctonia solani AG2-2 IV가 원인균이다. 한국잔디나 버뮤다글라스와 같은 난지형 잔디에 가장 중요한 병으로 알려져 있다. 본 연구는 갈색퍼짐병 발병토양의 미생물 군집 분석으로 생물적 방제제로 이용할 근거자료를 수집하기 위하여 실시하였다. 갈색 퍼짐병의 중심부(CLC)와 가장자리(CLE), 건전부(CLH)에서 채취한 근권부 토양의 미생물 군집(bacterial composition)을 Metagenomics 데이터 분석으로 Phylum 수준에서 조사한 결과 미생물상은 Proteobacteria, Acidobacteria, Chloroflexi, Firmicutes, Planctomycetes, Gemmatimonadetes, Nitrospira, Cyanobactria, Verrucomicrobia, Bacteroidetes 등의 순으로 분포 경향은 모두 유사하게 나타났다. 이에 반해 Actinobacteria의 경우 중심부에서 9.28%, 가장자리에서 10.84%로 건전부에서의 16%에 비하여 5~6% 정도 높은 비율로 분포하는 결과가 나타났다. Phylum 수준에서 중복되는 미생물의 종류를 조사한 결과 전체적으로 중심부에서는 총 6,948 OTUs가 분포하였으며 가장자리와 건전부에서는 각각 6,505와 5,537 OTUs 분포하는 것으로 나타났다. Actinobacteria의 경우 중심부의 총 OTUs는 615였으며 가장자리와 건전부는 709와 891 OTUs로 나타났다. 또한 모두 중복되는 OTUs도 382로 높게 나타났으나 서로 중복되지 않는 OTUs는 건전부에서 286으로 중심부와 가장자리가 91과 126 OTUs인 것에 비하여 2~3배 이상으로 월등히 높게 나타났다.

• Steel and Composite Structures
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• 제29권3호
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• pp.309-318
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• 2018

Steel girders are the structural members often used for passing long spans. Mostly being subjected to patch loading, or concentrated loading, steel girders are likely to face sudden deformation or damage e.g., web breathing. Horizontal or vertical stiffeners are employed to overcome this phenomenon. This study aims at assessing the feasibility of a machine learning method, namely the support vector machines (SVM) in predicting the patch loading resistance of longitudinally stiffened webs. A database consisting of 162 test data is utilized to develop SVM models and the model with best performance is selected for further inspection. Existing formulations proposed by other researchers are also investigated for comparison. BS5400 and other existing models (model I, model II and model III) appear to yield underestimated predictions with a large scatter; i.e., mean experimental-to-predicted ratios of 1.517, 1.092, 1.155 and 1.256, respectively; whereas the selected SVM model has high prediction accuracy with significantly less scatter. Robust nature and accurate predictions of SVM confirms its feasibility of potential use in solving complex engineering problems.

• 한국생산제조학회지
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• 제9권5호
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• pp.119-126
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• 2000

Recently, according to the various taste of consumers, the design of a product is changed variously and complicatedly. The complicated product is not usually constructed with one path but multi-path. By the way, in machining, higher precision and the reduction of leading and machining time is required. But, for the multi-patch sculptured surface, the amount of machining data becomes large. This means the increase of leading and machining time. In this study, the tool path generation method with reparameterization is proposed for multi-patch sculptured surface and variable step size using NURBS is used to satisfy the precision and to reduce leading and machining time.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1738-1745
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• 2015

Radiation characteristics of a probe-fed rectangular microstrip patch antenna printed on a finite grounded high permittivity substrate are investigated systematically for various square grounded dielectric substrate sizes with several thicknesses and dielectric constants by experiment and full wave simulation. The effect of the substrate size on the radiation characteristics of a rectangular patch antenna is mainly determined by the effective dielectric constant of surface waves on a grounded dielectric substrate. As the effective dielectric constant of surface waves increases, the substrate sizes for the maximum broadside gain and the required onset for a large magnitude of squint angle decrease, while the variations of the broadside gain, the front-to-back ratio, and the magnitude of squint angle versus the substrate size increase due to the increase of the power of the surface wave.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.548-549
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• 2014

Omni-directional shear-horizontal magnetostrictive patch transducers have a disadvantage that magnetic flux leakage into the plate when it is installed on a ferromagnetic plate. The leakage produces poor transduction efficiency and unwanted wave mode excitation which should be avoided in guided wave inspections of large plate-like structures. In order to resolve these problems, we newly developed a method to reduce the leakage into the plate. In the method, the patch and the magnet are vertically lifted off and their optimal positions are determined by numerical simulations. Also, the verification of the developed method is successfully verified by experiments.

• Journal of Chest Surgery
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• 제24권4호
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• pp.390-396
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• 1991

From July 1984 to September 1990, 316 patients of congenital heart diseases were operated and 15 patients died. Hospital mortality was 4.75%. Five patients of 73 PDA had residual shunt after operation: 4 were ligated under support of Dacron patch, 1 was closed through the pulmonary arteriotomy under CPB. 3 patients were reoperated. No patient had residual shunt or reopening among the patients of simple ligation or division and suture. During the ligation of PDA, Dacron patch for protection from tearing may disturb the complete interruption of shunt. If the tissue around the ductus arteriosus looks weak or fragile, division and suture may be more reliable other than ligation with supporting patch. If the septal leaflet of tricuspid valve is adherent around the VSD, remained opening of VSD may be closed with simple suture directly. In these cases, the incidence of postoperative residual shunt is as high as the incidence of more large VSD closed with patch [10.9%: 9.6%]. During the direct closure of remained opening of VSD, another leaking route should be looked for carefully beneath the septal leaflet of tricuspid valve.

• 융합보안논문지
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• 제4권2호
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• pp.43-51
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• 2004

운영체제 및 응용프로그램들은 프로그램 개발 과정의 특성상 보안 취약성을 가지고 있다. 최근 이러한 취약성을 악용하는 침해사례가 증가하고 있으며, 그 피해의 파급효과가 더욱 커지고 있다. 패치의 분배 및 설치는 취약성을 이용하는 침해사고를 예방하기 위한 가장 중요한 요소 중의 하나이다. 특정 기관이나 조직은 다양한 운영체제 및 응용프로그램을 사용하기 때문에 관리자가 매번 신속하게 모든 시스템들에 대하여 패치를 설치하기는 어려움이 있다. 본 논문에서는 중앙의 관리자가 패치관리서버를 이용하여 Windows, Linux, Solaris 클라이언트 시스템들에 대하여 안전하게 패치를 자동분배하고 설치하는 패치관리시스템을 설계 및 구현하였다 또한, 대규모 네트워크를 지원하기 위하여 확장성을 고려한 계층적인 패치 분배 구조로 설계 및 구현하였다.

• Journal of Information Processing Systems
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• 제13권5호
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• pp.1183-1202
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• 2017

Image restoration has been carried out by texture synthesis mostly for large regions and inpainting algorithms for small cracks in images. In this paper, we propose a new approach that allows for the simultaneous fill-in of different structures and textures by processing in a wavelet domain. A combination of structure inpainting and patch-based texture synthesis is carried out, which is known as patch-based inpainting, for filling and updating the target region. The wavelet transform is used for its very good multiresolution capabilities. The proposed algorithm uses the wavelet domain subbands to resolve the structure and texture components in smooth approximation and high frequency structural details. The subbands are processed separately by the prioritized patch-based inpainting with isophote energy driven texture synthesis at the core. The algorithm automatically estimates the wavelet coefficients of the target regions of various subbands using optimized patches from the surrounding DWT coefficients. The suggested performance improvement drastically improves execution speed over the existing algorithm. The proposed patch optimization strategy improves the quality of the fill. The fill-in is done with higher priority to structures and isophotes arriving at target boundaries. The effectiveness of the algorithm is demonstrated with natural and textured images with varying textural complexions.

• 아시안잔디학회지
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• 제13권4호
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• pp.201-212
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• 1999

In use of pesticides in golf courses has been increased steadily. Environmental concern as well as decrease in efficiency led the turfgrass management into an alternate approach of using beneficial microorganism to deal with turfgrass pests. This study was focused on the use of such microorganisms for improving cultural environment and minimizing the use of pesticides. Microorganisms antagonistic to turfgrass diseases were applied to zoysiagrass fairways and creeping bentgrass greens in Yusung country club. Tharch accumulation, disease occurrence, and other cultural environments were compared among the combinations of microorganisms and suppliemental N applications. The application of microorganisms antagonistic to turfgrass diseases improved turf resiliency. Thatch thickness was 3.03cm in the control plot but it was 2.11cm in plots treated by microorganisms, indicating significant effects of microorganism application on reduction of thatch accumulation. Number of microorganism that can decompose of cellulose was higher at the plots treated with useful microbial products and it was considered that existence of higher population of microorganisms resulted in reduction of thatch accumulation. In the evaluation of relationship between thatch accumulation and disease occurrence, greater thatch accumulation was observed at the golf courses which have been frequently infested by large patch. However, the rate of thatch accumulation varied among surveyed golf courses regardless of the year of turf establishment. Therefore, management practice which can be effective for reduction of thatch could result in large patch suppression. The application of microorganisms on the established turfgrasses reduced the occurrence rate of pythium blight and yellow path diseases, whereas occurrence of brown patch and dollar spot increased.