• 제목/요약/키워드: combined systems

Search Result 2,637, Processing Time 0.037 seconds

Speed Enhancement Technique for Ray Casting using 2D Resampling (2차원 리샘플링에 기반한 광선추적법의 속도 향상 기법)

  • Lee, Rae-Kyoung;Ihm, In-Sung
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.27 no.8
    • /
    • pp.691-700
    • /
    • 2000
  • The standard volume ray-tracing, optimized with octree, needs to repeatedly traverse hierarchical structures for each ray that often leads to redundant computations. It also employs the expensive 3D interpolation for producing high quality images. In this paper, we present a new ray-casting method that efficiently computes shaded colors and opacities at resampling points by traversing octree only once. This method traverses volume data in object-order, finds resampling points on slices incrementally, and performs resampling based on 2D interpolation. While the early ray-termination, which is one of the most effective optimization techniques, is not easily combined with object-order methods, we solved this problem using a dynamic data structure in image space. Considering that our new method is easy to implement, and need little additional memory, it will be used as very effective volume method that fills the performance gap between ray-casting and shear-warping.

  • PDF

In vivo Antioxidant Effects of Aralia elata Seemann Ethanol Extract Administered with Benzo($\alpha$) pyrene

  • Nam, Sang-Myung;Chung, Cha-Kwon
    • Preventive Nutrition and Food Science
    • /
    • v.4 no.1
    • /
    • pp.52-56
    • /
    • 1999
  • This study has examined the effects of Aralia elata Seemann ethanol extract on antioxidant enzyme systems inrats along with benzo($\alpha$) pyrene(B(a)P) administration . The ethanol extract of Aralia elata Seemann (50mg/kg body wt.) was fed to rats for 4 weeks by stomach tubing. The extract administration increased antioxidant activities of glutathione sulfur transferase(GST) comparing to the control. also total superoxide dismutase(SOD) and Cu, Zn-SOD activities were stimulated. Catalase activities were increased by 50% with the extract feeding compared to the control . Combined administration of B($\alpha$)P and the extract increased GST activity in B($\alpha$) P group. Although total SOD acitivity was decreased , Cu, Zn-SOD was greately increased from 0.10unit to 0.18 unit and catalase activity also was increased compared to the group of B($\alpha$) P. GST activity in CLE group was 1.32 unit, increased by 33% comparing to the group CL of 0.99unit. Cu, Zn-SOD and catalase activities in thegroup fed high fat and ethanol extracts were increased by 25% and 39%, respectivley comparing to the group of high fat. In addition , total SOD was decreased but, Cu, Zn-SOD acitivity was increased from 0.09 unit to 0.18unit. Catalase activity was 76.05 unit in the group of B($\alpha$) P and extract comparing to 65.26 units in B($\alpha$)P group. Serum $\alpha$-tocopherol of rat was markedly increased by theextract. Administration of B9$\alpha$)P reduced $\alpha$-tocopherol levels in the serum, on the other hand, lard in the diet increased $\alpha$-tocopherol levels in the serum. The above results indicate that Aralia bud exerts antioxidant functions in vivo against B($\alpha$)P. Further research may be necessary for the identification fo the biologically active material.

  • PDF

Design and Verification of Newly Developed Anti-jamming GPS Test System (새롭게 개발된 항재밍 위성항법장치 점검 시스템 설계 및 검증)

  • Kwon, Byung-Gi;Lee, Jong-Hong;Heo, Yong-Kwan;Lee, Chul
    • The Journal of the Korea Contents Association
    • /
    • v.15 no.12
    • /
    • pp.1-7
    • /
    • 2015
  • These anti-jamming GPS systems are verified using large anechoic chamber or field-test until now. When using a large anechoic chamber, Independent verification from external enviroments like noise is an advantage but high cost and availability of chamber are disadvantages. And in case of field test, verification under real propagation enviroment is an advantage but security problem of military equipments and problem of making same test condition are disadvantages. This paper presents an newly developed anti-jamming GPS test system. This test system mainly consists of small anechoic chamber, jamming divider, jamming signal generator and satellite simulator. The small anechoic chamber is installed many jamming antennas to transmit multi jamming signals and the jamming divider is newly developed to control multi jamming signals. According to self performance test and combined test with Anti-jamming GPS receiver, we verified our system's reliability.

Construction and Evaluation of Bank Marketing Database using Geographic Information Systems (GIS를 이용한 은행마케팅 데이터베이스의 구축과 과제)

  • Jo, Myung-Hee;Bu, Ki-Dong;Kim, Kwang-Ju;Suh, Jun-Seok
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.1 no.1
    • /
    • pp.52-69
    • /
    • 1998
  • Using GIS, this study constructs and evaluates a bank marketing system. The study collects a marketing GIS database case from the Daegu Bank, which is one of the leading local banks in Korea. The database includes spatial data such as digital road map, internal and external attribute data which are combined for the construction of bank marketing database. Based on these data, the study developed an interface which enables searching and analysing functions of bank GIS marketing system. For the development of the interface, this study examined the basic concepts of area marketing and its development and utilized Map/Info as a basic GIS software package and Delphi as computer language. Finally, the study makes a comprehensive evaluation of various problems of spatial and attribute data which occurred in the process of constructing the bank marketing database.

The Structure and Operations of Geodata Collaboratives in Metropolitan Area: U.S. Cases (미국 광역권 지리정보협력체 구성 및 운영방안)

  • Nam, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.10 no.4
    • /
    • pp.35-45
    • /
    • 2007
  • Currently, the necessity of inter-system integration and sharing system increases to additionally construct and efficiently utilize the geographical information data in accordance with the increase in demand for geographical information. The provision of the data within the domestic sharing system is led by the tasks within national geographical information distribution network or intra-local governmental combined system. However, any voluntary geographical information sharing cooperation body is increasingly required with the increase in necessity of administrative cooperation among neighboring metropolitan areas, including space planning and development. Accordingly, this study is aimed at looking into the constitutions and roles of cooperation bodies within metropolitan areas by the composition, distribution, update and management of data with special regard to overseas advanced cases whose sharing systems and their effects are highly evaluated, and at presenting any model of the domestic future voluntary sharing cooperation organization within metropolitan area.

  • PDF

Construction of Farmlands Spatial Information for Reasonable Adjustment of Farmland Use (합리적인 농지이용조정을 위한 농지공간정보구축)

  • Chung, Hoi-Hoon;Na, Sang-Il;Lee, Sang-Hyun;Choi, Jin-Yong
    • Journal of Korean Society of Rural Planning
    • /
    • v.15 no.4
    • /
    • pp.213-220
    • /
    • 2009
  • Farmland spatial data are needed as a basic information in conducting rational use of farmlands in regional scale. This study develops a method that can be used to make up such farmland spatial data in a simple way and to develop a technique to manage them in a unitary way, and examines the effectiveness of the technique by applying it to the case area. A method that Web-Service Raster Image and Digital Cadastal Map can be utilized as a base map was devised. It was designed applying the vector system, in which one lot of farmland is area unit. Raster image and field survey data were combined to increase the accuracy of data. The lot boundaries of the existing boundary map were adjusted to the shapes of actual farmlands using GIS edition function. A proper farmland use classification system to the area characteristics was established and data obtained from the field survey were coded. Usually it is very difficult to identify the size of one lot of actual farmland in the existing space data, based on the results of the case study, the result map showed actual topography very realistically. Also the frequently occurring lot divisions and the serious topographical modifications by natural disasters frequently have made it impossible to survey farmlands on the catastral map in the field. But the final map had a great usefulness in that it may solve such problems by expressing the filed survey results graphically.

Management of Ipsilateral Fractures of Humerus and Forearm in Adults (성인에서 동측에 발생한 상완골과 전완골 골절의 치료)

  • Sohn Sung-Keun;Kim Byeong-Hwan;Yang Sung-Wook
    • Clinics in Shoulder and Elbow
    • /
    • v.1 no.2
    • /
    • pp.212-220
    • /
    • 1998
  • Concomitant ipsilateral fractures of the humerus, radius and ulna are uncommon combined injury and are also called "floating elbow". It was found that this injury was usually a result of rather severe trauma and frequently associated injuries to other organ systems. It is controversial in the treatment of the "floating elbow", but the current treatment recommendations are open reduction and internal fixation of both the humerus and the forearm fracture with early initiation of range of motion exercises. The authors reviewed thirteen cases of ipsilateral fractures of the humerus, radius and ulna treated in our clinic from January 1992 to March 1997, and average follow-up period was over 18 months(range, 12 to 36 months). The results obtained were as follows; 1. The most common cause of injury was traffic accident and most common location of fractures was mid-third in both humerus and forearm. 2. The shape of fractures was transverse or comminuted in most cases. 3. The good clinical results were obtained by open reduction and internal fixation of both the humerus and the forearm fracture with early initiation of range of motion exercises. 4. The recovery was affected by the severity of the initial trauma and method of the treatment. 5. According to the Lange and Foster method, the functional result was good in 8 cases, fair in 4 cases and poor in 1 cases.

  • PDF

Beam-Column Element Applicable to Nonlinear Seismic Analysis (비선형 지진 해석을 위한 보-기둥 요소)

  • Kim, Kee Dong;Ko, Man Gi;Lee, Sang Soo
    • Journal of Korean Society of Steel Construction
    • /
    • v.9 no.4 s.33
    • /
    • pp.557-578
    • /
    • 1997
  • The objective of the study in this paper was to develop a beam-column element to model members with purely flexural yielding, as well as members with yielding under combined flexure and axial force during severe earthquake ground motins. The developed element can be considered as an one-component series hinge type model. It has the capability to model plastic axial deformation and changes in axial stiffness, and employs hardening rules to handle monotonic, cyclic or arbitrary loading. In general, when compared to experimental results and fiber model predictions, the element showed significantly better performance than the bilinear hinger model and could properly model the beam-column behavior of bare steel members in moment resisting frames. The developed element can more accurately predict local deformation demands and overall responses of structural systems under earthquake loadings than the bilinear hinge element.

  • PDF

An efficient method and performance analysis for burst synchronization/error detection using cyclic codes (순환코드를 이용한 효율적인 동기/에러 검출 방법 및 성능분석)

  • 최양호
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.21 no.8
    • /
    • pp.2013-2022
    • /
    • 1996
  • Cyclic Codes can be used for burs(or time slot) synchronization as well as error detection as that the overhead bits of the burst, which would be nessary to seperate burst synchronization and error detection systems, may be eliminated. In this paper a new method for combined burst synchronization and error detection is proposed which requires CRC decoding once only, while the previous method which inspects channel error after searching for burst synchronization requeires CRC decoding twice. The proposed method has the advantage of simple implementation and reducing processing time over the previous one, still showing the same detection perfdormance. It may occur that a burst different from the actually transmitted one is falsely accepted in the presence of channel errors. The exact expression for the false acceptance probability is newly presented through a simple derivation basied on the fact that it is determined by channel errors but not by detection methods.

  • PDF

Manufacturing of High Water-Resistant Particleboard by Combining Use of Urea Resin and EMDI Resin (요소수지와 EMDI수지의 복합이용에 의한 고내수정 파티클보드의 제조)

  • Park, Jong-Young
    • Journal of the Korean Wood Science and Technology
    • /
    • v.26 no.1
    • /
    • pp.97-105
    • /
    • 1998
  • This study examined the combined using effects of urea-formaldehyde (UF) resin and emulsifiable methylene diphyenyl diisocyanate (EMDI) resin to overcome performance limit of three-layer particleboards commonly made by UF resin. Two adhesive adding methods were applied with three types of resin combination system to each layer of particleboards. The one was simultaneously spreading method with emulsified compound resin (UF and EMDI) while the other was separately spreading method with unemulsified EMDI resin after UF resin spreading. The performance of particleboards bonded with 2% EMDI resin to the inner layers(IL) were similar to that of controls bonded with 8% UF resin. In the case of the emulsified compound resin application to the all layers of particleboards, there were marked reinforcing effects of EMDI resin, although a small amount of EMDI resin was mixed with UF resin. Especially bending MOR after 24 hours cold water-immersion and thickness swelling after 2 hours hot water-immersion of compound resin-bonded particleboards were remarkably different from those of pure UF resin-bonded particleboards. It was found that separately spreading method with unemulsified EMDI resin was more effective than simultaneously spreading method with emulsified compound resin to sustain the internal bond strength of particleboards after 24 hours cold water-immersion. In the resin combination systems to outer layers/inner layers of particleboards, water resistance and strength properties were superior in order of UF+EMDI/UF+EMDI > UF/UF+EMDI > UF/UF. And water resistance of particleboards was greatly dependent upon EMDI resin level in any adhesive adding method.

  • PDF