• 제목/요약/키워드: probability-based

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상황 전파 네트워크를 이용한 확률기반 상황생성 모델 (Probability-Based Context-Generation Model with Situation Propagation Network)

  • 천성표;김성신
    • 로봇학회논문지
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    • 제4권1호
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    • pp.56-61
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    • 2009
  • A probability-based data generation is a typical context-generation method that is a not only simple and strong data generation method but also easy to update generation conditions. However, the probability-based context-generation method has been found its natural-born ambiguousness and confliction problems in generated context data. In order to compensate for the disadvantages of the probabilistic random data generation method, a situation propagation network is proposed in this paper. The situation propagating network is designed to update parameters of probability functions are included in probability-based data generation model. The proposed probability-based context-generation model generates two kinds of contexts: one is related to independent contexts, and the other is related to conditional contexts. The results of the proposed model are compared with the results of the probabilitybased model with respect to performance, reduction of ambiguity, and confliction.

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Validation of Statistical Analysis-based Aberrancy Probability Using Marine Simulations

  • Kim, Sung-Cheol
    • 해양환경안전학회지
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    • 제24권3호
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    • pp.332-338
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    • 2018
  • To perform the Maritime Safety Audi Scheme, $10^{-4}$ was constantly applied without adjustment when evaluating the proximity of the fairway. The necessity of applying the different aberrancy probabilities from the different proximity of the fairway depending on the shape of the route and the size of the ship was validated using marine simulations. Marine simulation was performed to evaluate the validity of statistical analysis-based aberrancy probability according to the different shapes of routes and ship size presented in the previous study. As results, the validity of the criterion of the statistical analysis-based aberrancy probability was confirmed by comparing with the results of simulation-based aberrancy probabilities. The results support that the aberrancy probabilities by the types of a vessel could be different based on the type and size of vessels. The results motivate that further investigation is required to find the reasonable criteria of the aberrancy probabilities for the maritime traffic safety audit according to the fairway shape and the size of the vessel.

확률기반 비신호교차로의 우회전 전용차로 설치 기준 정립 (Establishing Probability-Based Warrants for Right-Turn Lanes at Unsignalized Intersections)

  • 문재필
    • 한국도로학회논문집
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    • 제19권6호
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    • pp.183-190
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    • 2017
  • PURPOSES : The objective of this study is to establish the traffic volume-based warrants of right-turn lanes at unsignalized intersections and to introduce a risk probability methodology based on the warrants. METHODS : In this study, a risk probability of a potential rear-end collision is applied between a right-turn vehicle and the immediately following through vehicle. Using the shifted negative exponential model and the compound probability theorem, the risk probability can be expressed as the function of directional volumes and the percentage of right-turns for a two-lane and four-lane highway, respectively. RESULTS : Based on the risk probablity, guidelines for installing right-turn lanes on two-lane and four-lane highways were developed. The risk probability also showed rationality by comparing with right-turn same-direction conflicts observed in-situ. CONCLUSIONS : The results of our study define the total approaching volumes to encourage a right-turn lane as a function of operating speed, percentage of right-turn, and number of lanes.

Contention-based Reservation MAC Protocol for Burst Traffic in Wireless Packet Networks

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • 제5권2호
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    • pp.93-97
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    • 2007
  • In this paper, centralized access control and slot allocation algorithm is proposed for wireless networks. The proposed algorithm is characterized by the contention-based reservation. In order to reduce the collision probability of reservation request, the base station calculates and broadcasts the transmission probability of reservation requests, and the wireless terminal transmits its reservation request with the received transmission probability. The scheduler allocates the uplink data slots based on the successful reservation requests. Simulation results show that the proposed algorithms can provide high channel utilization, and furthermore, maintains constant delay performance in the heavy traffic environment.

Calculation of Life-Time Death Probability due Malignant Tumors Based on a Sampling Survey Area in China

  • Yuan, Ping;Chen, Tie-Hui;Chen, Zhong-Wu;Lin, Xiu-Quan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권10호
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    • pp.4307-4309
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    • 2014
  • Purpose: To calculate the probability of one person's life-time death caused by a malignant tumor and provide theoretical basis for cancer prevention. Materials and Methods: The probability of one person's death caused by a tumor was calculated by a probability additive formula and based on an abridged life table. All data for age-specific mortality were from the third retrospective investigation of death cause in China. Results: The probability of one person's death caused by malignant tumor was 18.7% calculated by the probability additive formula. On the same way, the life-time death probability caused by lung cancer, gastric cancer, liver cancer, esophageal cancer, colorectal and anal cancer were 4.47%, 3.62%, 3.25%, 2.25%, 1.11%, respectively. Conclusions: Malignant tumor is still the main cause of death in one's life time and the most common causes of cancer death were lung, gastric, liver, esophageal, colorectal and anal cancers. Targeted forms of cancer prevention and treatment strategies should be worked out to improve people's health and prolong life in China. The probability additive formula is a more scientific and objective method to calculate the probability of one person's life-time death than cumulative death probability.

확률론적 방법을 적용한 콘크리트 구조물의 염해 내구성 설계에 관한 연구 (A study on Probability-based Durability Design of Concrete Structures subjected to Chloride Attack)

  • 김원동;송하원;변근주;백승우
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.161-164
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    • 2005
  • A probability-based durability design which minimizes the uncertainties on durability parameters of concrete is proposed for reinforced concrete structures subjected to chloride attack. The uncertainties of various factors such as water-cement ratio, curing temperature, age of concrete and the variation of these factors which affect chloride ion diffusion are considered. For the durability design, a probability-distribution function for each factor is obtained and a program which combines Fick's 2nd law and Monte Carlo simulation is developed. The durability design method proposed in this study considers probability of durability limit and probability of the concentration of chloride ion, so that the probability-based deterioration prediction is possible.

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Analysis of structural dynamic reliability based on the probability density evolution method

  • Fang, Yongfeng;Chen, Jianjun;Tee, Kong Fah
    • Structural Engineering and Mechanics
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    • 제45권2호
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    • pp.201-209
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    • 2013
  • A new dynamic reliability analysis of structure under repeated random loads is proposed in this paper. The proposed method is developed based on the idea that the probability density of several times random loads can be derived from the probability density of single-time random load. The reliability prediction models of structure based on time responses under several times random loads with and without strength degradation are obtained by using the stress-strength interference theory and probability density evolution method. The resulting differential equations in the prediction models can be solved by using the forward finite difference method. Then, the probability density functions of strength redundancy of the structures can be obtained. Finally, the structural dynamic reliability can be calculated using integral method. The efficiency of the proposed method is demonstrated numerically through a speed reducer. The results have shown that the proposed method is practicable, feasible and gives reasonably accurate prediction.

Efficient Channel State Feedback Scheme for Opportunistic Scheduling in OFDMA Systems by Scheduling Probability Prediction

  • Ko, Soomin;Lee, Jungsu;Lee, Byeong Gi;Park, Daeyoung
    • Journal of Communications and Networks
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    • 제15권6호
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    • pp.589-600
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    • 2013
  • In this paper, we propose a new feedback scheme called mode selection-based feedback by scheduling probability prediction (SPP-MF) for channel state feedback in OFDMA downlink system. We design the scheme such that it determines the more desirable feedback mode among selective feedback by scheduling probability prediction (SPP-SF) mode and bitmap feedback by scheduling probability prediction (SPP-BF) mode, by calculating and comparing the throughputs of the two modes. In both feedback modes, each user first calculates the scheduling probability of each subchannel (i.e., the probability that a user wins the scheduling competition for a subchannel) and then forms a feedback message based on the scheduling probability. Specifically, in the SPP-SF mode, each user reports the modulation and coding scheme (MCS) levels and indices of its best S subchannels in terms of the scheduling probability. In the SPP-BF mode, each user determines its scheduling probability threshold. Then, it forms a bitmap for the subchannels according to the scheduling probability threshold and sends the bitmap along with the threshold. Numerical results reveal that the proposed SPP-MF scheme achieves significant performance gain over the existing feedback schemes.

위험도 기반 접근법에 의한 선박 복원성의 확률 예측 (Probability Prediction of Stability of Ship by Risk Based Approach)

  • 용전군;정재훈;문병영
    • 한국유체기계학회 논문집
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    • 제16권2호
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    • pp.42-47
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    • 2013
  • Ship stability prediction is very complex in reality. In this paper, risk based approach is applied to predict the probability of a certified ship, which is effected by the forces of sea especially the wave loading. Safety assessment and risk analysis process are also applied for the probabilistic prediction of ship stability. The survival probability of ships encountering with different waves at sea is calculated by the existed statistics data and risk based models. Finally, ship capsizing probability is calculated according to single degree of freedom(SDF) rolling differential equation and basin erosion theory of nonlinear dynamics. Calculation results show that the survival probabilities of ship excited by the forces of the seas, especially in the beam seas status, can be predicted by the risk based method.

Implementation of a Web-Based Electronic Text for High School's Probability and Statistics Education

  • Choi, Sook-Hee
    • Communications for Statistical Applications and Methods
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    • 제11권2호
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    • pp.329-343
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    • 2004
  • With advancement of computer and network, world wide web(WWW) as a medium of information communication is generalized in many fields. In educational aspect, applications of WWW as alternative media for class teachings or printed matters are increasing. In this article, we demonstrate a web-based electronic text on the 'probability and statistics' which is one of six fields of mathematics in the 7th curriculum. This text places importance on comprehension of concepts of probability and statistics as an applied science.