• Title/Summary/Keyword: Sight Distance

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A Study on Quantitative Analysis Method of Museum Architecture Arrangement - Focused on Space Syntax and Visibility Graph Analysis - (뮤지엄건축 공간배치의 정량적 분석방법에 관한 연구 -공간구문론(Space Syntax)과 가시장분석(Visibility Graph Analysis)을 중심으로 -)

  • Park, Chong-Ku;Lee, Sung-Hoon
    • Korean Institute of Interior Design Journal
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    • v.18 no.4
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    • pp.97-104
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    • 2009
  • This thesis analyzed arrangement and mixture method of function elements, which are getting more important in museum planning. It used quantitative method, Space Syntax and Visibility Graph Analysis tool to analyze five case museums. Through this analysis, advantages and disadvantages of two methods were derived and case museums' arrangement and mixture attributes were grasped. Results of the analysis were derived differently by two kinds of plan form which were room to room type and open type. Open typed museum recorded similar graphs of Integration, Visual Integration and Visual Connectivity. Since whole space structures were relatively simple and structure of exhibition halls were opened, the results of Space Syntax and Visibility Graph Analysis had similar graphs. Room to room typed museum showed differences in Integration, Visual Integration and Visual Connectivity. In the result, the most accessible space was lobby and Mediation Space became the center of visibility. Also, the exhibition hall, where the opening of room to room typed exhibition hall was penetrated visually, became a center of visibility. Lobby space, which was close to entrance, had the highest Visibility Connectivity. As Space Syntax could analyze the museum as whole space structure, Space Syntax showed strength in room to room typed museum analysis compared to open typed museum analysis which has relatively simple structure. Visibility Graph Analysis could expect the flow of exhibit distance including visibility analysis unlike the flow of exhibit distance with space arrangement. The exhibition hall, which secures the sight to penetration of an opening, couldn't be analyzed in existing Space Syntax. However, it became the biggest advantages in Visibility Graph Analysis of room to room typed museum. Visibility Graph Analysis derived detailed results in exhibit arrangement so it will be the useful method not only for architecture but also for planning of exhibit arrangement in open typed museum. Through this study, various possibilities on Quantitative Analysis Method of Museum Architecture could be verified. However, the analysis still has limitation of second dimension. Therefore, diverse and liberal following study will be expected to accomplish.

A study on the sharing between NGSO/MSS service link and existing fixed-service microwave system (NGSO / MSS 서비스링크와 기존 고정서비스 마이크로웨이브 시스템간의 주파수 공유에 관한 연구)

  • 이성수;조삼모;김혁제
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.1
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    • pp.115-125
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    • 1998
  • This paper examined the feasibility of adding a new NGSO/MSS(Non-Geostationary orbit/Mobile satellite service) service link to a frequency band which is already allocated to fixed-service microwave(M/W) system. To achieve this goal, the NGSO/MSS handset performance under the influence of the M/W multiple stations and the influence of handsets on the M/W station were both analyzed. Sharing criterions were also obtained by means of coordination contour in the former case, and handset capacity in the latter case. As the results, it was proven that sharing was feasible only when the vertical distance between handset and trendline was above 4 km except front and back points of M/W antenna bore sight under influence of 9 hops(the distance between hops = 50 km) M/W system on the NGSO/MSS handset, and only when the capacity of handset was below $7.0\times10^{-14}$ handsets/ $m^{2}$ under influence of handsets on the M/W station.

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A Study on the Factors that Affect the Submarine's Depth-rate on the Vertical Plane (수직평면에서 잠수함의 심도변화율에 영향을 주는 제 요소에 관한 연구)

  • 윤점동;김종훈;윤종휘
    • Journal of the Korean Institute of Navigation
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    • v.13 no.3
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    • pp.21-36
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    • 1989
  • The submarine played an active part in military operation during the last of nineteenth century. Today, as an aid to science and technology and technology m the submarine is being utilized in the fields of deep sea investigation and sight-seeing as well as military activities. When the stability and the maneuverability of a submarine is studied, the problems arise on the vertical plane as well as the horizontal plane. However, the horizontal plane has been dealt with in the study of surface vessels. The author attempts to look into the hydrodynamic directional stability at high speeds (above 10knots) on the vertical plane, and to clarify the submarine's depth-rate as related to the factors that affect it : the distance from the center of buoyancy to the center of gravity, the speed of the submarine, and the position and the area ratio of hydroplane. In this study, the author considered the two groups of dimensionless derivatives of submarine. It is confirmed that the depth-rate of a submarine is decreased when the length, of BG is increased under the continuous submerging status. But the depth-rate is increased when the area ratio of hydroplane is enlarged. It is also confirmed that a submarine has only one critical speed in accordance with the shape of its hull, but unconcerned with its speeds.

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Cosmological Tests using Redshift Space Clustering in BOSS DR11

  • Song, Yong-Seon;Sabiu, Cristiano G.;Okumura, Teppei;Oh, Minji;Linder, Eric V.
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.43.3-44
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    • 2015
  • We analyze the clustering of large scale structure in the Universe in a model independent method, accounting for anisotropic effects along and transverse to the line of sight. A large sample of 690,000 galaxies from The Baryon Oscillation Spectroscopy Survey Data Release 11 are used to determine the Hubble expansion H, angular distance D_A, and growth rate GT at an effective redshift of z=0.57. After careful bias and convergence studies of the effects from small scale clustering, we find that cutting transverse separations below 40 Mpc/h delivers robust results while smaller scale data leads to a bias due to unmodelled nonlinear and velocity effects. The converged results are in agreement with concordance LCDM cosmology, general relativity, and minimal neutrino mass, all within the $68{\backslash}%$ confidence level. We also present results separately for the northern and southern hemisphere sky, finding a slight tension in the growth rate -- potentially a signature of anisotropic stress, or just covariance with small scale velocities -- but within $68{\backslash}%$ CL.

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16-QAM OFDM-Based K-Band LoS MIMO Communication System with Alignment Mismatch Compensation

  • Kim, Bong-Su;Kim, Kwang-Seon;Kang, Min-Soo;Byun, Woo-Jin;Song, Myung-Sun;Park, Hyung Chul
    • ETRI Journal
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    • v.39 no.4
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    • pp.535-545
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    • 2017
  • This paper presents a novel K-band (18 GHz) 16-quadrature amplitude modulation (16-QAM) orthogonal frequency-division multiplexing (OFDM)-based $2{\times}2$ line-of-sight multi-input multi-output communication system. The system can deliver 356 Mbps on a 56 MHz channel. Alignment mismatches, such as amplitude and/or phase mismatches, between the transmitter and receiver antennas were examined through hardware experiments. Hardware experimental results revealed that amplitude mismatch is related to antenna size, antenna beam width, and link distance. The proposed system employs an alignment mismatch compensation method. The open-loop architecture of the proposed compensation method is simple and enables facile construction of communication systems. In a digital modem, 16-QAM OFDM with a 512-point fast Fourier transform and (255, 239) Reed-Solomon forward error correction codecs is used. Experimental results show that a bit error rate of $10^{-5}$ is achieved at a signal-to-noise ratio of approximately 18.0 dB.

Changes in High Degree p-mode Parameters with Magnetic and Flare Activities

  • Maurya, Ram Ajor
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.89.2-89.2
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    • 2013
  • Solar energetic transients, e.g., flares, CMEs, etc., release large amount of energy which is expected to excite acoustic waves (p-modes) by exerting mechanical impulse of the thermal expansion of the flare on the photosphere. We study the p-mode properties of flaring and dormant active regions (ARs) to find association between flare and p-mode parameters. We compute the magnetic and flare activity indices of ARs using the line-of-sight magnetograms and GOES X-ray fluxes, respectively. The p-mode parameters are computed from the ring-diagram analysis. We correct p-mode parameters for magnetic field, filling factors and foreshortening by multiple linear-regression analysis. Our analysis of several flaring and dormant ARs observed during the Carrington rotations 1980-2109, showed strong association of mode parameters with magnetic and flare activities. We find that the mode parameters are contaminated by the geometrical effect. Mode amplitude decreases with angular distance from the solar disc centre. The mode width increases with magnetic activity while amplitude showed opposite relation due to mode absorption by the sunspot. After correcting modes due to all geometrical effects, magnetic activity and filling factor, we find that the modes amplitude, and mode energy increases with flare energy while width shows opposite relation.

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A Technique to Efficiently Place Sensors for Three-Dimensional Robotic Manipulation : For the Case of Stereo Cameras (로봇의 3차원 작업을 위한 효율적 센서위치의 결정기법 : 스테레오 카메라를 중심으로)

  • Do, Yong-Tae
    • Journal of Sensor Science and Technology
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    • v.8 no.1
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    • pp.80-88
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    • 1999
  • This paper deals with the position determination problem of stereo camera systems used as a sensor for 3D robotic manipulation. Stereo cameras having parallel rays of sight and been set up on the same baseline are assumed. The distance between the sensor and the space measured is determined so as to get insensitive parameters to the uncertainty of control points used for calibration and to satisfy the error condition set by considering the repeatability of the robot. The baseline width is determined by minimizing the mutual effect of 3D positional error and stereo image coordinate error. Unlike existing techniques, the technique proposed here is developed without complicated constraints and modelling process of the object to be observed. Thus, the technique of this paper is more general and its effectiveness is proved by simulation.

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A Self-Calibrated Localization System using Chirp Spread Spectrum in a Wireless Sensor Network

  • Kim, Seong-Joong;Park, Dong-Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.2
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    • pp.253-270
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    • 2013
  • To achieve accurate localization information, complex algorithms that have high computational complexity are usually implemented. In addition, many of these algorithms have been developed to overcome several limitations, e.g., obstruction interference in multi-path and non-line-of-sight (NLOS) environments. However, localization systems those have complex design experience latency when operating multiple mobile nodes occupying various channels and try to compensate for inaccurate distance values. To operate multiple mobile nodes concurrently, we propose a localization system with both low complexity and high accuracy and that is based on a chirp spread spectrum (CSS) radio. The proposed localization system is composed of accurate ranging values that are analyzed by simple linear regression that utilizes a Big-$O(n^2)$ of only a few data points and an algorithm with a self-calibration feature. The performance of the proposed localization system is verified by means of actual experiments. The results show a mean error of about 1 m and multiple mobile node operation in a $100{\times}35m^2$ environment under NLOS condition.

THE SIMPLE METHOD OF GEOMETRIC RECONSTRUCTION FOR SPOT IMAGES

  • JUNG HYUNG-SUP;KIM SANG-WAN;WON JOONG-SUN
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.205-207
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    • 2004
  • The simple method of the geometric reconstruction of satellite linear pushbroom images is investigated. The model of the sensor used is based on the SPOT model that is developed by Kraiky. The satellite trajectory is a Keplerian trajectory in the approximation. Four orbital parameters, longitude of the ascending $node(\omega),$ inclination of the orbit plan(I), latitude argument of the satellite(W) and distance between earth center and satellite, are used for the camera modeling. We suppose that four orbital parameters and satellite attitude angles are exactly acquired. Then, in order to refine model, the given attitude angles and orbital parameters is not changed, but time-independent four parameters associated with LOS(Line Of Sight) vector is updated. A pair of SPOT-5 images has been used for validation of proposed method. Two GCPs acquired by GPS survey is used to controlling the LOS vector. The results are that the RMSE of 16 checking points are about 4.5m. Because the ground resolution of SPOT-5 is 2.5m, the result obtained in this study has a good accuracy. It demonstrates that the sensor model developed by this study can be used to reconstruct the geometry of satellite image taken by pushbroom camera.

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Backstepping-Based Control of a Strapdown Boatboard Camera Stabilizer

  • Setoodeh, Peyman;Khayatian, Alireza;Farjah, Ebrahim
    • International Journal of Control, Automation, and Systems
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    • v.5 no.1
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    • pp.15-23
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    • 2007
  • In surveillance, monitoring, and target tracking operations, high-resolution images should be obtained even if the target is in a far distance. Frequent movements of vehicles such as boats degrade the image quality of onboard camera systems. Therefore, stabilizer mechanisms are required to stabilize the line of sight of boatboard camera systems against boat movements. This paper addresses design and implementation of a strapdown boatboard camera stabilizer. A two degree of freedom(DOF)(pan/tilt) robot performs the stabilization task. The main problem is divided into two subproblems dealing with attitude estimation and attitude control. It is assumed that exact estimate of the boat movement is available from an attitude estimation system. Estimates obtained in this way are carefully transformed to robot coordinate frame to provide desired trajectories, which should be tracked by the robot to compensate for the boat movements. Such a practical robotic system includes actuators with fast dynamics(electrical dynamics) and has more degrees of freedom than control inputs. Backstepping method is employed to deal with this problem by extending the control effectiveness.