• Title/Summary/Keyword: Distance Geometry

Search Result 361, Processing Time 0.05 seconds

Singularity-Circumvented Computation of Green's Functions for 2D Periodic Structures in Homogeneous Medium

  • Kahng, Sung-Tek
    • Journal of electromagnetic engineering and science
    • /
    • v.7 no.2
    • /
    • pp.59-63
    • /
    • 2007
  • This paper suggests a novel method to efficiently calculate the spatial-domain Green's functions of 2D electromagnetic problems Briefly speaking, this method combines spectral and spatial domain calculation schemes and prevents the Green's functions from poor convergence due to the singularities that complicate the process of the Method of Moment(MoM) applications For the validation of this proposed method, fields will be evaluated along the spatial distance including zero distance for 2D free-space and periodic homogeneous geometry The numerical results show the validity of the prosed method and correspondng physics.

Min-Sum ${\lambda}$ Discrete 2-Center Problem (거리의 합이 최소가 되는${\lambda}$ 이산 2-중심 문제)

  • Shin, Chan-Su;Wolff, Alexahder
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.29 no.6
    • /
    • pp.340-345
    • /
    • 2002
  • In this paper, we deal with the following facility location problem. Given a set P of n points in the plane, find two (discrete) centers p and q in P that minimize the sum of there distance plus the distance of any other point to the closer center. In this paper, we propose an Ο(n$^2$1ogn)-time algorithm to compute the two centers.

NMR STRUCTURE DETERMINATION OF A NOVEL CONOTOXIN, [Pro 7,13] $\alpha$A-conotoxin $P_{IVA}$

  • Han, Kyou-Hoon;Hwang, Kae-Jung;Kim, Seung-Moak;Kim, Soo-Kyung;William R. Gray;Shon, Ki-Joon;Jean Rivier;Baldomero M. Olivera
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1996.07a
    • /
    • pp.10-10
    • /
    • 1996
  • High-resolution solution conformation of a novel conotoxin, [Pro 7,13] $\alpha$A-conotoxin $P_{IVA}$, GCCGSYPNAACHPCSCKDROSYCGQ-N $H_2$, has been determined by two-dimensional $^1$H nmr methods in combination with distance geometry calculation to rmsd values of 0.90 $\AA$ and 1.16 $\AA$ for the backbone and heavy atoms, respectively. Total of 324 NOE-derived interproton distance restraints including 33 long-range NOE restraints a well as 11 $\Phi$ and 7 $\chi$$^1$ torsion angle restraints were used for computation of structures. (omitted)d)

  • PDF

A study on the influence of wheel/rail geometric parameters to equivalent conicity (차륜/레일 기하학적 인자의 등가답면구배에 미치는 영향)

  • Hur Hyun-Moo;Kwon Sung-Tae;Kim Hyung-Jin
    • Proceedings of the KSR Conference
    • /
    • 2004.10a
    • /
    • pp.430-434
    • /
    • 2004
  • The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination to the equivalent conicity relating dynamic behavior. The analyses show the following results. The widening of wheel flange-back distance increase the equivalent conicity, the widening of gage, rail inclination 1/20 compared with rail inclination 1/40 decrease the equivalent conicity.

  • PDF

Proposal of Singularity-Circumvented Green's Functions for 2D Periodic Structures in Homogeneous Medium (특이점이 제거된 2 차원 단일매질 주기구조에 대한 그린함수의 제안)

  • Kahng, Sung-Tek;Kim, Hyeong-Seok
    • Proceedings of the KIEE Conference
    • /
    • 2006.10a
    • /
    • pp.133-134
    • /
    • 2006
  • In this paper, a novel method is presented for efficient calculation of the spatial-domain Green's functions of 2D electromagnetic problems. This method combines spectral and spatial domain calculation schemes and prevents the Green's functions from diverging at the singularities that complicate the process of the Method of Moment(MoM) application. For the validation of this proposed method, fields will be evaluated along the spatial distance including zero distance for 2D free-space and periodic homogeneous geometry. The numerical results show the validity of the prosed method and correspondng physics.

  • PDF

Solution-State Structure of Native Coenzyme F430 by NMR Methods

  • 원호식;Karl D. Olson;박지석;Ralph S. Wolfe;Dennis R. Hare;Michael F. Summers
    • Bulletin of the Korean Chemical Society
    • /
    • v.16 no.7
    • /
    • pp.649-653
    • /
    • 1995
  • Solution-state structure of native F430 was determined by using NMR methods and NMR-based distance geometry (DG) computations. Structures were generated with loose NOE-derived interproton distance restraints (2.0-2.5 Å, 2.0-3.5 Å and 2.0-4.5 Å for strong, medium, and weak NOE cross-peak intensities, respectively). 2D NOESY back-calculations of structures were subsequently carried out for establishing the consistence between experimental data and DG-model structures. The back-calculated 2D NOESY spectra of resulting DG structures were well consistent with experimental 2D NOESY spectra. Superposition of 20 independent structures with macrocyclic ring atoms and all atoms of F430 afforded pairwise root mean square deviations (RMSD) of 0.025-0.125 Å and 0.64-1.3 Å, respectively. The macrocyclic rings of structures are well converged to a unique conformation with saddle-shaped deformation whereas most of side chains are not converged. The average dihedral angle (N1-N2-N3-N4, 27.78±1.50°) of 20 DG-structures exhibits that the macrocyclic ring conformation is puckered as much as 12,13-diepimeric F430 (28.75±4.07°).

Effect of the distance between the adjacent injectors on penetration and mixing characteristics of the jet in supersonic crossflow (수평 배치된 분사구의 배치 간격에 따른 초음속 유동장 내 분사 유동의 침투 및 혼합 특성)

  • Kim, Sei Hwan;Lee, Hyoung Jin
    • Journal of Aerospace System Engineering
    • /
    • v.12 no.4
    • /
    • pp.81-89
    • /
    • 2018
  • In the present study, a numerical investigation was conducted to analyze the effect of the distance between the adjacent injectors on the characteristics of flow structure, fuel penetration, and air/fuel mixing. Numerical results were validated with experimental data using a single injection. Subsequently, the same injector geometry and properties were applied on a non-reacting flow simulation with multiple injectors. Total pressure loss, penetration height, and mixing efficiency were compared with the distance between the injectors. The results showed that each injected gas merged into a single stream, resulting in the 2D-like flow fields under the condition of short distance and lower mixing efficiency along with higher total pressure loss. When the distance between the injectors increased, total pressure loss reduced and mixing efficiency increased due to the weakening of interactions between the injected gases.

A Study on the Installation Method of Delineation System Using Detection Distance and Lateral Position (인지거리와 측방위치를 이용한 시선유도시설의 설치방법에 관한 연구)

  • Jeon, Woo-Hoon;Cho, Hye-Jin
    • International Journal of Highway Engineering
    • /
    • v.9 no.3
    • /
    • pp.29-38
    • /
    • 2007
  • This study investigated the effects of delineation systems on drivers' maneuver and how the effectiveness of delineation system can be further improved according to the road geometry. The experiments were conducted to collect lateral placement data and detection distance data using GPS equipped vehicles. The main results are summarizedas follows. Firstly, installing the delineation facilities on the roads helps drivers to recognize road alignment. Secondly, the detection distance is longer for delineators than for raised pavement marker in tangent section, while there is no difference in curve section. The chevron show the longest detection distance in the curve section, while the raised pavement markers showed no distinctive performance in terms of detection distance and lateral placement. Therefore, we can recommend install delineators in the tangent sections and chevrons in curve sections, based on the analysis results of effects of delineation facilities.

  • PDF

Sensitivity analysis of input variables to establish fire damage thresholds for redundant electrical panels

  • Kim, Byeongjun;Lee, Jaiho;Shin, Weon Gyu
    • Nuclear Engineering and Technology
    • /
    • v.54 no.1
    • /
    • pp.84-96
    • /
    • 2022
  • In the worst case, a temporary ignition source (also known as transient combustibles) between two electrical panels can damage both panels. Mitigation strategies for electrical panel fires were previously developed using fire modeling and risk analysis. However, since they do not comply with deterministic fire protection requirements, it is necessary to analyze the boundary values at which combustibles may damage targets depending on various factors. In the present study, a sensitivity analysis of input variables related to the damage threshold of two electrical panels was performed for dimensionless geometry using a Fire Dynamics Simulator (FDS). A new methodology using a damage evaluation map was developed to assess the damage of the electrical panel. The input variables were the distance between the electrical panels, the vertical height of the fuel, the size of the fire, the wind speed and the wind direction. The heat flux was determined to increase as the vertical distance between the fuel and the panel decreased, and the largest heat flux was predicted when the vertical separation distance divided by one half flame length was 0.3-0.5. As the distance between the panels increases, the heat flux decreases according to the power law, and damage can be avoided when the distance between the fuel and the panel is twice the length of the panel. When the wind direction is east and south, to avoid damage to the electrical panel the distance must be increased by 1.5 times compared to no wind. The present scale model can be applied to any configuration where combustibles are located between two electrical panels, and can provide useful guidance for the design of redundant electrical panels.

A Experiment Study of Torch Distance on Automated Tandem GMA Welding System (탄뎀 가스메탈아크 용접의 토치 극간거리에 관한 실험적 연구)

  • Lee, Ji-Hye;Kim, Ill-Soo;Jung, Seong-Myeong;Lee, Jong-Pyo;Kim, Young-Su;Park, Min-Ho
    • Journal of Welding and Joining
    • /
    • v.30 no.6
    • /
    • pp.49-55
    • /
    • 2012
  • The tandem welding process is one of the most efficient welding processes widely used in material joining technique such as manufacturing of strong and durable structures. It facilitates high rate of joint filling with little increase in the overall rate of heat input due to the simultaneous deposition from two electrode wires. The two electrodes in tandem welding process helps in high-efficiency and high productive of welding process. In this study a automated tandem welding system is developed to determine the correlation between cathode and anode and compared with current ratio of the two electrode torch. Three different inter-electrode distances were chosen, 25mm, 35mm and 45mm to perform the experiment with three different current ratio. From the experiment results, the current ratio between two torch has a large impact on width, height and depth of penetration. In addition, a stable bead geometry is obtained when inter-electrode distance is 35mm.