• Journal of Electrical Engineering and information Science
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• 제2권5호
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• pp.33-39
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• 1997

In this paper we proposed a new traffic load shedding scheme which maximizes the throughput of traffic control by decreasing the load of the hot-spot cell using minimum load cell selection (MLCS) algorithm and deployed control flow of calls to define characteristic for hadoff region. we compared the performance of the random shedding approach with that of the proposed algorithm. The results of simulation show that MLCS algorithm minimizes the cal blocking rate under a high-density traffic compared to the random shedding scheme.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.859-864
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• 2001

An effective live load model for analyzing probable maximum live load effects such as moment and shear in transverse direction was developed. The main procedure of this live load model is composed of four parts, i.e., firstly, determination of the appropriate influence lines in longitudinal direction, secondly, application of the characteristics of vehicles and traffic patterns in longitudinal direction, thirdly, determination of the appropriate influence lines in transverse direction, and fourthly, application of the characteristics of vehicles and traffic patterns in transverse direction. Through this procedure, the probabilistic distributions of maximum probable load effects are deduced in the form of probability density function (PDF) and/or cumulative density function(CDF). This live load model is able to consider local or global deterioration of bridges in the structural analysis.

• 한국소음진동공학회논문집
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• 제17권3호
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• pp.274-281
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• 2007

Road traffic noise is not produced by any one factor rather it occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of any noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examines the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/h, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.277-282
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• 2006

Road traffic noise is not produced by any one factor rather occurs as a composition of various factors. Its occurrence is made by running engine noise, tire frictional, and exhaust noise etc. The quality of the noise depends on the size of the vehicles, rotation and engine speed, vehicle load, package state of the road and incline etc. The occurrence of noise level of heavy trucks appears louder than smaller vehicles and the noise levels produced differs according to speed and load etc between similar size vehicles. Other factors such as traffic density, average speed, mixing rate of heavy vehicles, and the distance between vehicles also generate road traffic noise. In this paper we examine 2, 4, and 6-lane roads in Jeonju. Consequently, this study examined the means used to measure road traffic noise. It was found that when there is a large traffic density and the average velocity is below 70 km/hr, the noise level could receive a relative proper value by the current measuring means. But in the case of night-time, it was found that the current measuring method is inapposite.

• 한국통신학회논문지
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• 제33권7A호
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• pp.757-767
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• 2008

차세대 이동 통신망의 발전으로 상용 망과 이 기종 망이 서로 겹쳐진 다중 망 구조가 형성될 것이다. 이러한 여러 망이 겹쳐진 다중 망 구조에서 전체 무선자원의 사용 효율을 높이고 Eb/Io (bit energy-to-interference plus noise density ratio)를 개선하기 위해 이기종망간 혹은 동종망간 상호 연동 기술이 필요하다. 본 논문에서는 이러한 동종망과 이기종망들이 서로 겹쳐져 있는 다중 셀 환경에서 load를 효율적으로 분산시킴으로써 무선 자원의 효율을 높이고 신호의 간섭양을 줄여 사용자의 QoS 보장 및 성능 개선을 위한 soft load balancing algorithm을 제안 및 분석한다. 본 논문에서는 수학적 분석을 통해 효율적인 load sharing을 위한 최적의 LBR (load balancing ratio) 을 구하고 이를 이용하여 각 network에 traffic 양을 할당하여 서비스한다. 그러므로 soft load balancing 알고리듬은 보다 안정적인 데이터 전송을 가능하게 한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.865-870
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• 2001

An effective live load model for analyzing probable maximum live load effects in longitudinal direction such as moment and shear was developed. The main procedure of this live load model is composed of two parts. Firstly, determination of the appropriate influence lines, and secondly, application of the characteristics of vehicles and traffic patterns. Through this procedure, probabilistic distributions of maximum probable load effects are deduced in the form of probability density function (PDF) or cumulative density function (CDF). The proposed live load model is not limited by bridge types(number of spans or girders) and can consider local or global deterioration of bridges in the analysis. Besides, load effects can be determined at any section without restrictions.

• 한국도로학회논문집
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• 제8권3호
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• pp.29-37
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• 2006

본 연구는 현재 수행중인 "한국형 포장 설계법 개발과 포장성능 개선방안 연구"의 일환으로 역학-경험적 포장 설계법에 사용될 교통하중 입력변수를 정량화하기 위해서 실시하였다. 교통하중 정량화를 위하여 기존의 ESAL 개념이 아닌 축하중 스펙트럼을 이용하였다. 이를 위하여 교통량 통계 연보내 교통량 자료를 가지고 일반 국도에 대한 대표 축하중 조사지점을 차로별, 지역특성별 구분에 따라 33개 지점을 통계적 방법을 이용하여 선정하였다. 그리고 선정된 대표 지점을 대상으로 축하중 계측기를 이용하여 각 차종에 대한 축하중을 조사하였다. 측정된 축하중 자료는 각각 분류된 조건에 따라서 축하중 스펙트럼으로 표준화하였으며, 그 방법으로 누적밀도함수인 S-커브 곡선을 이용하여 각 조건별 계수를 제시하였다.

• 대한교통학회지
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• 제20권5호
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• pp.67-79
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• 2002

교통량, 교통밀도, 교통류 속도 등, 교통류 변수에 대한 현재까지의 불확실한 정의와 연속적 파동방정식의 거시적 교통류 해석상의 문제점을 지적하고 이를 개선하기 위해 교통류 변수들에 대한 새로운 확률적 정의를 제시하고 이들의 성격을 규명하였다. 이러한 새로운 교통류 변수들에 대한 새로운 정의를 바탕으로 미시적 운전자 행동을 세밀하게 수용할 수 있고 많은 교통환경에서 연속적 파동 방정식을 대체하여 교통류 변수들과 통행시간을 예측할 수 있는 미분방정식 체계를 확률 미분방적식을 이용하여 도출하였다. 도출된 미분 방정식을 단일 차량의 시공 괘적에 적용해 보았다.

• 한국통신학회논문지
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• 제31권12A호
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• pp.1189-1197
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• 2006

Ultra-wideband(UWB) is a killer technology for short-range wireless communications. In the past, most of the UWB research focused on physical layer but the unique characteristics of UWB make it different to design the upper layer protocols than conventional narrow band systems. Cross-layer protocols have received high attention for UWB networks. In this paper, we investigate the performance of two physical layer schemes: Time Hopping Binary Pulse Position Modulation(TH-BPPM) and Time Hopping Binary Pulse Amplitude Modulation (TH-BPAM) with proposed private MAC protocol for UWB ad-hoc networks. From pulse level to packet level simulation is done in network simulator ns-2 with realistic network environments for varying traffic load, mobility and network density. Our simulation result shows TH-BPAM outperforms TH-BPPM in high traffic load, mobility and dense network cases but in a low traffic load case identical performance is achieved.

• 전자통신동향분석
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• 제33권5호
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• pp.42-50
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• 2018

UDN is expected to be a type of network capable of satisfying the requirements various 5G services, such as the peak data rate, connection density, and area traffic capacity. Technical challenges for 5G UDN, such as interference management, resource management, mobility management, load balancing, and energy efficiency are discussed. In addition, candidate technologies for solving these challenges, and their related standardization trends, are summarized in this article.