• Title/Summary/Keyword: compute simulation

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Collision Risk Assessment for Pedestrians' Safety Using Neural Network (신경 회로망을 이용한 보행자와의 충돌 위험 판단 방법)

  • Kim, Beom-Seong;Park, Seong-Keun;Choi, Bae-Hoon;Kim, Eun-Tai;Lee, Hee-Jin;Kang, Hyung-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.1
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    • pp.6-11
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    • 2011
  • This paper proposes a new collision risk assessment system for pedestrians's safety. Monte Carlo Simulation (MCS) method is a one of the most popular method that rely on repeated random sampling to compute their result, and this method is also proper to get the results when it is unfeasible or impossible to compute an exact result. Nevertheless its advantages, it spends much time to calculate the result of some situation, we apply not only MCS but also Neural Networks in this problem. By Monte carlo method, we make some sample data for input of neural networks and by using this data, neural networks can be trained for computing collision probability of whole area where can be measured by sensors. By using this trained networks, we can estimate the collision probability at each positions and velocities with high speed and low error rate. Computer simulations will be shown the validity of our proposed method.

Inventory Control Policies for a Hospital Blood Bank: A Simulation and Regression Approach (병원의 혈액 재고관리를 위한 평가 모형 : 시뮬레이션 및 회귀분석 방법)

  • Suh, Jeong-Dae
    • IE interfaces
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    • v.10 no.1
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    • pp.119-134
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    • 1997
  • The management of blood inventory is very important within the medical care system. The efficient management of blood supplies and demands for transfusions is of great economic and social importance to both hospitals and patients. For any blood type, there is a complex interaction among the optimal inventory level, daily demand level, daily supply level, transfusion to crossmatch ratio, crossmatch release period, issuing policy and the age of arriving units that determine the shortage and outdate rate. In this paper, we develop an efficient decision rule for blood inventory management in a hospital blood bank which can support efficient hospital blood inventory management using simulation. The primary use of the efficient decision rule will be to establish minimum cost function which consists of inventory levels, period in inventory, outdate and shortage rate for whole blood and various component inventories for a hospital blood bank or a transfusion service. If the administrator compute the mean daily demand for each blood type, the mean daily supply for each blood type, the length of the crossmatch release period and the average transfusion to crossmatch ratio, then it is possible to apply the efficient decision rule to compute the optimal inventory level, inventory period, outdate and shortage rate. This rule can also be used as a decision support system that allows the blood bank administrator to do sensitivity analysis related to controllable blood inventory parameters.

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Blocking Probability in an M/D/1/K Queue (M/D/1/K 대기행렬에서의 차단확률)

  • Seo, Dong-Won
    • Journal of the Korea Society for Simulation
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    • v.17 no.4
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    • pp.241-247
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    • 2008
  • In this study we consider an M/D/1 queue with a finite buffer. Due to the finiteness of the buffer capacity arriving customers can not join the system and turn away without service when the buffer is full. Even though a computational method for blocking probabilities in an M/D/1/K queue is already known, it is very complex to use. The aim of this study is to propose a new way to compute blocking probability by using (max,+)-algebra. Our approach provide a totally different and easier way to compute blocking probabilities and it is, moreover, immediately applicable to more generous queueing systems.

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Numerical and random simulation procedure for preliminary local site characterization and site factor assessing

  • Beneldjouzi, Mohamed;Laouami, Nasser;Slimani, Abdennasser
    • Earthquakes and Structures
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    • v.13 no.1
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    • pp.79-87
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    • 2017
  • Seismic analysis of local site conditions is fundamental for a reliable site seismic hazard assessment. It plays a major role in mitigation of seismic damage potential through the prediction of surface ground motion in terms of amplitude, frequency content and duration. Such analysis requires the determination of the transfer function, which is a simple tool for characterizing a soil profile by estimating its vibration frequencies and its amplification potential. In this study, numerical simulations are carried out and are then combined with a statistical study to allow the characterization of design sites classified by the Algerian Building Seismic Code (RPA99, ver 2003), by average transfer functions. The mean transfer functions are thereafter used to compute RPA99 average site factors. In this regard, coming up seismic fields are simulated based on Power Spectral Density Functions (PSDF) defined at the rock basement. Results are also used to compute average site factor where, actual and synthetic time histories are introduced. In absence of measurement data, it is found that the proposed approach can be used for a better soil characterization.

A Practical Method to Compute the Closest Approach Distance of Two Ellipsoids (두 타원체 사이의 최단 근접 거리를 구하는 실용적인 방법)

  • Choi, Min Gyu
    • Journal of Korea Game Society
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    • v.19 no.1
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    • pp.5-14
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    • 2019
  • This paper presents a practical method to compute the closest approach distance of two ellipsoids in their inter-center direction. This is the key technique for collision handling in the dynamic simulation of rigid and deformable bodies approximated with ellipsoids. We formulate a set of equations with the inter-center distance and the contact point and normal for the two ellipsoids contacting each other externally. The equations are solved using fixed-point iteration and Aitken's delta-squared process. In addition, we introduce a novel stopping criterion expressed in terms of the error in distance. We demonstrate the efficiency and practicality of our method in various experiments.

A Performance Evaluation of Multimedia-on-demand Server Using Simulation Method (시뮬레이션 기법을 이용한 주문형 멀티미디어 서버의 성능 평가)

  • 박기진
    • Journal of the Korea Society for Simulation
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    • v.7 no.2
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    • pp.33-43
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    • 1998
  • To evaluate the server performance and forecast capacity requirements, we carry out simulation of Multimedia-on-demand(MOD) server. In multimedia service environment, especially for on-demand service, one of the key problems is capacity planning, which requires ensuring that adequate computer resources will be available to meet the future workload demands in a cost-effective manner. In this paper, we design and implement a simulation model for MOD server with failures of components (e.g., processors, disks and networks). By acquisition of utilization and queue length parameters, we can estimate desirable capacity of server components with various arrival rates of customers and failure rates of components. For a given failure probability, we also compute packet delay probability and reliability of the server. It is possible to derive some important design information of the MOD server by using the above parameters.

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Visualization of Internal Electric Field on Plasma (플라즈마 내부 전기장 가시화)

  • Shin, Han Sol;Yu, Tae Jun;Lee, Kun
    • Journal of Korea Multimedia Society
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    • v.19 no.1
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    • pp.80-85
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    • 2016
  • It costs high in both memory usage and time consuming to sample the space to compute charge density and calculate electric field on that with large size of plasma data. In real-time and interactive application, accelerating the compute time is critical problem. In this paper, we suggest new method to visualize electric field by using convolution theorem, and the parallel computing to accelerate computing time by using GPGPU. We conduct a simulation that compare running time between the methods with convolution and without convolution. We discussed the method of visualization of multivariate data in three dimensional space using colored volume rendering and surface construction.

A Study on Integrated Small Signal Stability Analysis of Power Systems (계통의 종합적 미소신호 안정도해석에 관한 연구)

  • Nam, Ha-Kon;Song, Sung-Geun;Kim, Yong-Gu;Shim, Kwan-Shik
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.1033-1036
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    • 1998
  • In this research project, two aspects of small signal stability are studied: improvement in Hessenberg method to compute the dominant electromechanical oscillation modes and siting FACTS devices to damp the low frequency oscillation. Fourier transform of transient stability simulation results identifies the frequencies of the dominant oscillation modes accurately. Inverse transformation of the state matrix with complex shift equal to the angular speed determined by Fourier transform enhances the ability of Hessenberg method to compute the dominant modes with good selectivity and small size of Hessenberg matrix. Any specified convergence tolerance is achieved using the iterative scheme of Hessenberg method. Siting FACTS devices such as SVC, STACOM, TCSC, TCPR and UPFC has been studied using the eigen-sensitivity theory of augmented matrix. Application results of the improved Hessenberg method and eigen-sensitivity to New England 10-machine 39-bus and KEPCO systems are presented.

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Integrator initial value selection in the guidance laws for attitude controlled missile (자세제어방식 유도탄에 대한 유도법칙의 적분기 초기치 선정)

  • 윤원식;류창경;조항주
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.450-455
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    • 1993
  • Guidance commands for attitude controlled missiles inevitably take the form of attitude angle commands. On the other hand, many guidance laws compute the accelerations required to achieve their goals. Therefore some integrators must be in use for the attitude controlled missiles to implement the guidance laws. Naturally, the use of the integrator raises the problem of choosing a proper initial value. In this paper, we compute the integrator initial value which minimizes the terminal miss and show that if the total flight time of the mission is long enough, the "optimal" initial value becomes some multiple of the initial heading error or of the given impact angle to the target. We demonstrate the validity of the analysis by showing some linear and nonlinear simulation results.n results.

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Computation method of effective bandwidth of VBR MPEG video traffic using the modified equivalent capacity (수정된 equivalent capcity를 이용한 VBR MPEG 비디오 트랙픽의 등가대역폭 계산방법)

  • 하경봉;이창범;박래홍
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.10
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    • pp.40-47
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    • 1996
  • A method for computing effectiv ebandwidth of aggregated varable bit rate (VBR) moving picture experts group (MPEG) video traffic is proposed. To compute statistical characteristics of aggregated MPEG traffic, first we split input MPEG traffic into I, B, and P frame traffics and aggregate respective I, B, and P frame traffics according to the frame type. Second statisticsal characteristics of the aggregated MPEG traffic are obtained using those of aggregated I, B, and P frame traffics. The effective bandwidth of the aggregated I frame traffic is computed by using the gaussian bound. Using the modified equivalent capacity, we obtain the effective bandwidths of aggregated B and P frame traffics and then compute the effective bandwidth of the combined B and P frame traffic. Finally the effective bandwidth of the aggregated MPEG traffic is computed by adding the gaussian bound of the aggregated I frame traffic and modifed equivalent capacity of combined B and P frame traffic. Computer simulation shows that the proposed method estimates effective bandwidth of the aggregated MPEG traffic well.

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