• Title/Summary/Keyword: Large patch

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Landscape Ecological Studies on Structure and Dynamics of Plant Populations on Vegetation-Landscape Patterns in Rural Regions: I. The Effect of Patch Shape on the Initial Population Structure of Pine and Oaks

  • Rim, Young-Deuk;Hong, Sun-Kee
    • The Korean Journal of Ecology
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    • v.22 no.2
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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.

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Soil Microbial Community Analysis in Large Patch (Rhizoctonia solani AG2-2 IV) (갈색퍼짐병 발병토양의 미생물 군집 분석)

  • Lee, Jung Han;Min, Gyu Young;Shim, Gyu Yul;Jeon, Chang Wook;Choi, Su min;Han, Jeong Ji;Kwak, Youn-Sig
    • Weed & Turfgrass Science
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    • v.4 no.2
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    • pp.124-128
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    • 2015
  • Large patch, caused by Rhizoctonia solani AG2-2 IV, is a soil-born disease that is the most important of warm season turfgrass such as zoysia and Bermuda grass. This study was conducted to analysis of the soil microbial community structure on large patch. Center of the large patch (CLC), edge (CLE) and healthy (CLH) part of microbial communities were examined using metagenomics in Phylum level. Distribution trends of the rhizosphere microorganisms were similar to the order Proteobacteria, Acidobacteria, Chloroflexi, Firmicutes, Planctomycetes, Gemmatimonadetes, Nitrospira, Cyanobactria and Verrucomicrobia in soil collections. Contrastively Actinobacteria was more 56% abundant in healthy part soil (16%) than in the center (9.28%) or edge (10.84%) parts. Taxonomic distributions were compared among the CLC, CLE and CLH, total 6,948 OTUs were detected in the CLC, 6,505 OTUs for the CLE and 5,537 OTUs were detected in the CLE. Distributions of Actinobacteria OTUs were appeared 615 OTUs in the CLC, 709 OTUs in the CLE and 891 OTUs in the CLH. Among Actinobacteria, 382 OTUs were overlapped in the all soils. Not matched OTUs of CLH (286 OTUs) was detected 23 times higher than CLC (91 OTUs) and CLE (126 OTUs).

Patch load resistance of longitudinally stiffened webs: Modeling via support vector machines

  • Kurtoglu, Ahmet Emin
    • Steel and Composite Structures
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    • v.29 no.3
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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.

Tool Path Generation of Multi-Patch Sculptured Surface with Reparameterization (여러 개의 패치로 이루어진 곡면에서 재매개변수화를 통한 공구경로 생성)

  • 이성근
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.5
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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.

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Radiation Characteristics of a Probe-Fed Microstrip Patch Antenna on a Finite Grounded High Permittivity Substrate

  • Kwak, Eun-Hyuk;Yoon, Young-Min;Kim, Boo-Gyoun
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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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.

Development of an omni-directional shear-horizontal wave magnetostrictive patch transducer for the effective inspection of a ferromagnetic plate (효과적인 강자성체 평판구조물 검사를 위한 전 방향 전단파 자기변형 패치 트랜스듀서 개발)

  • Seung, Hong Min;Kim, Yoon Young
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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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.

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Clinical Study for Surgical Treatment of Congenital Heart Diseases (선천성 심혈관 질환의 수술요법에 관한 임상적 고찰)

  • 양태봉
    • Journal of Chest Surgery
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    • v.24 no.4
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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.

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Design and Implementation of Patch Management System for Improving System Security (시스템 보안성 향상을 위한 패치관리시스템 설계 및 구현)

  • 서정택;윤주범;최대식;박응기;박춘식
    • Convergence Security Journal
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    • v.4 no.2
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    • pp.43-51
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    • 2004
  • Operating systems and application programs have security vulnerabilities derived from the software development process. Recently, incident cases related with the abuses of these vulnerabilities are increasing and the damages caused by them are becoming very important security issues all over the nations. Patch management is one of the most important processes to fix vulnerabilities of softwares and to ensure a security of systems. Since an institute or a company has distributed hierarchical and heterogeneous systems, it is not easy to update patches promptly. In this paper, we propose patch management framework to safely distribute and install the patches on Windows, Linux, and Solaris client systems. Besides, we considered extensibility and hierarchical structure for our patch management framework to support large scaled network environment.

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Image Restoration and Object Removal Using Prioritized Adaptive Patch-Based Inpainting in a Wavelet Domain

  • Borole, Rajesh P.;Bonde, Sanjiv V.
    • Journal of Information Processing Systems
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    • v.13 no.5
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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.

The use of beneficial microorganisms to improve turfgrass quality and usability (유용미생물의 시용이 잔디의 질과 이용성에 미치는 영향)

  • 황연성;최준수
    • Asian Journal of Turfgrass Science
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    • v.13 no.4
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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.