• 한국컴퓨터정보학회논문지
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• 제11권4호
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• pp.47-54
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• 2006

교통사고를 줄이기 위해서, 많은 연구원이 교통사고 예측 모형을 연구하고 있다. 교통사고의 원인으로는 교차로 신호주기가 잘못 산출되거나 교차로 설계가 잘못된 경우가 많다. 그러므로, 정확하게 교통사고 원인을 분석하려면 많은 노력이 필요하다. 본 논문에서는 교차로 조건 및 날씨조건을 고려하여 최적 자동차 안전 속도를 실시간으로 산출하고자한다. 특별히, 비가 오거나 눈이 오는 경우에는 자동차 속도를 1/3이상 감속해야 된다. 그러나, 기존의 속도표지판은 기상조건이 바뀌어도 항상 같은 제한 속도를 표시하는 문제점이 있다. 본 논문에서는 이러한 문제점을 해결하기 위해서 날씨조건과 도로조건을 이용한 최적 안전속도 산출 알고리즘을 제시한다. 컴퓨터 모의실험결과, 지능형 교통사고 예측알고리즘이 교통 제한속도를 정확하게 산출할 수 있음을 입증했다.

• 전자공학회논문지A
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• 제32A권3호
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• pp.411-417
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• 1995

Packet switching is an important aspect of ISDN. In the TDX-10 switching system, which is being developed as an ISDN exchange in Korea, the packet switching function is implemented on the basis of Case B scenario of X.31. After implementing the packet switching function the performance test must be executed to check whether the design objectives of performance are satisfied or not. However, it is not easy to set up test environment for performance measurement under full load conditions. This paper presents the design of the traffic generator which enables us to do performance test of the TDX-10 packet handler under full load conditions. To generate packet traffic we change only software programs without any change of the hardware system of the packet handler.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.34-41
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• 2005

Construction of the Shinkansen was planned on the basis of a traffic volume determined by the Trunk Line Investigation Committee set up within JNR in 1957. Passenger and freight traffic along the vitally important Tokaido Main Line had been steadily increasing, passenger traffic reaching $24\%$ and freight $23\%$ of the total domestic traffic. Train frequency was expected to reach the upper limit in the 1960s. Estimated traffic volume was 13,000 million passenger-km for the opening year 1964 and 20,000 million for 1975. Although the traffic did not reach the estimed figure during 1975 reached about twice the estimated figure for the Tokyo-Shinoska Section. The amazing growth of the national economy was undoubtedly responsible for this.

• Journal of Communications and Networks
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• 제14권3호
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• pp.310-318
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• 2012

Detecting intrusion attacks accurately and rapidly in wireless networks is one of the most challenging security problems. Intrusion attacks of various types can be detected by the change in traffic flow that they induce. Wireless industrial networks based on the wireless networks for industrial automation-process automation (WIA-PA) standard use a superframe to schedule network communications. We propose an intrusion detection system for WIA-PA networks. After modeling and analyzing traffic flow data by time-sequence techniques, we propose a data traffic prediction model based on autoregressive moving average (ARMA) using the time series data. The model can quickly and precisely predict network traffic. We initialized the model with data traffic measurements taken by a 16-channel analyzer. Test results show that our scheme can effectively detect intrusion attacks, improve the overall network performance, and prolong the network lifetime.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.693-695
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• 2007

This study describes the proposed methods for constructing the residential section which satisfies quiet environment and scenery at the same time. For the purpose of achieving this objective, the influences of house arrangement, house skyline change, soundproofing facility installation, etc. on traffic noise environment and scenery are compared using document investigation and computational results.

• 한방안이비인후피부과학회지
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• 제17권3호
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• pp.138-145
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• 2004

The clinical features and therapeutic results of alopecia areata are variable and unpredictable. For example, genetic, psychic, immunologic factors are regarded as the reason of alopecia areata. For the relationship between alopecia and whiplash injury, Dr. Guun explained that whiplash injury by the traffic accident produces cervical muscle spasm, and it makes autonomic nerve change. The tropical changes accompanied with ischemic change of scalp vessels made by this mechanism cause alopecia areata. And Yesudian reported the case of scalp alopecia as the result of ischemic change following traffic accident. We have experienced a 25-year-old woman with Alopecia areata following whiplash injury by traffic accident, and who had no risk factor of it. The patient was treated by acupuncture and physical treatment. Her hair loss, cervical angle and pain were improved through acupuncture treatment. This case of alopecia areata following whiplash injury is uncommon, so we report the mechanism of it, but should collect more cases and observations.

• 한국산학기술학회논문지
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• 제8권3호
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• pp.639-645
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• 2007

본 연구에서는 우리나라의 인터넷전화 통화수요함수를 2001년 6월부터 2004년 12월까지의 월별 데이터를 이용하여 추정하고 있다. 추정식에서 인터넷 통화수요는 통화요금, 타서비스의 요금, 소득, 품질 등의 함수로 가정하였으며, 통화량의 부분적응모형을 이용하여 시차변수도 설명변수에 포함시켰다. 추정결과 인터넷전화는 해당 요금에 대해 탄력적인 것으로 파악되었고 소득에 대하여는 비탄력적으로 나타났다. 품질은 인터넷전화수요에 큰 영향을 미치는 것으로 파악되었으며 인터넷전화 통화수요가 설명변수의 변화에 대하여 반응하는데 있어 시차가 존재함을 보이고 있다.

• 한국ITS학회 논문지
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• 제19권3호
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• pp.38-51
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• 2020

고속도로에서 공사로 인한 차로폐쇄가 발생하면 병목이 형성되어 혼잡이 발생한다. 따라서 공사구간의 도로 운영효율을 개선하기 위해 다양한 교통관리전략이 개발되었으며, 대표적으로 공사구간 상류에 운영하는 합류제어가 있다. 일반차 환경에서는 혼잡시 운전자가 합류에 어려움을 겪어 전략 운영에 한계가 존재하나, 자율협력주행차는 통신기능을 활용하여 고도화된 교통관리전략의 운영이 가능하다. 이에 본 연구는 자율협력주행차 환경에서 동적합류제어와 차로변경제어를 통합한 교통관리전략을 개발하였다. 통합제어전략은 공사구간 상류의 점유율을 기준으로 조기합류 또는 지연합류를 운영하며, 비공사차로의 차로별 교통량을 균형화 하기 위해 차로를 변경할 차량수를 결정한다. 미시교통시뮬레이션에 자율협력주행차와 전략을 구현하고 분석한 결과 누적 통과교통량, 공사구간 상류의 평균속도 및 네트워크 평균통행시간이 개선되어 도로 운영성이 향상된 것을 확인하였다.

• 한국도로학회논문집
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• 제17권4호
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• pp.117-126
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• 2015

PURPOSES : This study aims to investigate the direct and indirect influence areas from incidents on urban interrupted roadways and to develop traffic management strategies for each influence area. METHODS : Based on a literature review, various traffic management strategies for certain incidents were collected. In addition, the relationship between the measure of effectiveness and the characteristics of incidents was explored using an extensive simulation study. RESULTS : From the simulation studies, traffic delays increased as the number of lane closures increased, and the impact of lane closures was reduced to the direction upstream from the incident site. However, the magnitude of the delay change depended on the degree of saturation. Using these characteristics, the direct and indirect influence areas resulting from incidents were defined, and traffic management strategies were established for each direct and indirect influence area and for each level of incident. CONCLUSIONS: The results of this study will contribute to the improvement of national traffic safety by preventing secondary incidents and by effective adaptation to incident events.

• 대한산업공학회지
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• 제29권2호
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• pp.135-144
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• 2003

Traffic performance in a microcellular system is much more affected by cell dwell time and channel holding time in each cell. Cell dwell time of a call is characterized by its mobility pattern, i.e., stochastic changes of moving speed and direction. Cell dwell time provides important information for other analyses on traffic performance such as channel holding time, handover rate, and the average number of handovers per call. In the next generation mobile communication system, the cell size is expected to be much smaller than that of current one to accommodate the increase of user demand and to achieve high bandwidth utilization. As the cell size gets small, traffic performance is much more affected by variable mobility of users, especially by that of pedestrians. In previous work, analytical models are based on simple probability models. They provide sufficient accuracy in a simple second-generation cellular system. However, the role of them is becoming invalid in a picocellular environment where there are rapid change of network traffic conditions and highly random mobility of pedestrians. Unlike in previous work, we propose an improved probability model evolved from so-called Random walk model in order to mathematically formulate variable mobility of pedestrians and analyze the traffic performance. With our model, we can figure out variable characteristics of pedestrian mobility with stochastic correlation. The above-mentioned traffic performance measures are analyzed using our model.