http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
CONSTRUCTION OF EUCLIDEAN VORONOI DIAGRAM FOR 3D BALLS BY TRACING EDGES
Youngsong CHO,Donguk KIM,Deok-Soo KIM 한국산업응용수학회 2005 한국산업응용수학회 학술대회 논문집 Vol.- No.-
Despite its important applications in various disciplines in science and engineering, the Euclidean Voronoi diagram for balls in 3D space has not been studied as much as it deserves. In this paper, we present an algorithm to compute the Euclidean Voronoi diagram for 3D balls with different radii. The presented algorithm follows Voronoi edges one by one until the construction is completed in O(mn) time in the worst-case, where m is the number of edges in the Voronoi diagram and n is the number of spherical balls.
조영송(Youngsong Cho),김재관(Jae-Kwan Kim),유중현(Joonghyun Ryu),이목원(Mokwon Lee),차제현(Jehyun Cha),송찬영(Chanyoung Song),김덕수(Deok-Soo Kim) (사)한국CDE학회 2014 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2014 No.8
Geometric properties are critical for the function of molecules consisting of atoms with different radii which are usually modeled as spheres in 3D. “Molecular Geometry” is a theoretical framework of computational understanding of the geometry of molecules in the claim that most molecular structure problems can be effectively and efficiently facilitated by the “geometrization” of the problem into that among spheres in 3D whose solution can be easily found via “geometry kernel”. In this paper, we report BULL!, the molecular geometry engine based on the Voronoi diagram of spheres, the quasi-triangulation, and the beta-complex. Being a program implemented in C++, application programmers can simply call API-functions of BULL! to create application programs correctly, efficiently, and conveniently. The BULL! is designed compatibly so that application programs are completely independent of future modifications and improvements. The BULL! engine will be freely available from the Voronoi Diagram Research Center at Hanyang University.
클라이언트 버퍼 상태를 고려한 오디오 패킷의 동적 부가 전송 기법
조민웅(Minwoong Cho),문영성(Youngsong Mun) 한국정보과학회 2000 한국정보과학회 학술발표논문집 Vol.27 No.2Ⅲ
본 논문에서는 VOD시스템, 혹은 영상회의 시스템에서의 오디오 패킷의 QOS를 보장해 주기 위해 클라이언트의 버터 상태에 따른 전송속도 제어와 부가 전송 기법을 동적으로 사용하여 재전송 함으로써 오디오 패킷의 손실문제를 해결하기 위한 방법과 함께 클라이언트의 버퍼 상황을 파악하여 전송속도를 조절하여 클라이언트의 버터에서의 오버프로우와 언더플로우를 방지하여 VOD와 영상회의 시스템에서 오디오 데이터의 전송시 안정적인 서비스를 보장할 수 있다.
Ryu, JoongHyun,Cho, Dongsoo,Cho, Youngsong,Kim, Deok-Soo 한국경영과학회 1999 한국경영과학회 학술대회논문집 Vol.- No.1
Intersection problem occurs in various engineering application areas, such as CAD/CAM, GIS, computer graphics, etc. Most of all, intersection algorithms are fundamental to CAD/CAM. Parametric curves have been frequently used in CAGD and thus intersection algorithm between parametric curves been studied intensively in several respects such as the speed, the robustness and the efficiency. Although many intersection algorithms have been published, there exists no algorithm that is satisfactory in all the above three aspects. The intersection techniques that appear in the literature can be classified into three categories; Newton-Raphson iteration method, subdivision method and implicitization method. Newton-Raphson iteration-wise method shows a good convergence rate in case that a good initial seed is given. Otherwise, it provides a wrong solution or diverges. Bezier clipping algorithm copes with intersection problem like an intelligent Newton method. Though it is faster than Implicitization algorithm and Interval subdivision for curve of degree less than 5. Intersection algorithm based on subdivision method divides the original intersection problem into easier ones and then conquers the each divided problem. Be´zier subdivision and interval subdivision algorithm is included in this category. Implicitization method transforms intersection problem to the problem of finding a single polynomial root by substitution a parametric from curve into the implicitized curves. This approach is known to be fastest in computing the intersections between curves of degrees less than quintics. In this paper, an algorithm for intersecting Bezier curves is provided and is extended to an algorithm for intersections between NURBS curves. The algorithm characterized both curves to be intersected and approximates them in lower degree curves. Implicitization technique is applied to the intersections between approximated low degree curves for locating initial solution. Then a good initial solution is obtained and Newton-Raphson iteration converge to a true intersection quickly abs robustly. Tangential case overlapping case are not considered in the pro^+posed algorithm.