• 한국정보통신학회논문지
• /
• 제13권2호
• /
• pp.355-361
• /
• 2009

본 논문에서는 목표 비트량에 맞게 영상을 압축하는 베이직 유닛 레벨 비트율 제어 알고리즘을 제안한다. H.264 비디오 압축 표준은 다양한 압축 모드 및 최적화 방법을 사용하여 압축률을 향상 시키지만 복잡한 인코더 구조는 정확한 트래픽 제어를 어렵게 한다. 제안된 알고리즘에서는 한 프레임에 할당된 목표 비트량과 일치하는 결과 비트율을 생성하기 위해 한 프레임에 할당된 비트량을 각 베이직 유닛에 적절하게 분배하였고 목표치와 결과치의 차이를 다음 프레임에 반영하여 트래픽이 목표치에 수렴할 수 있게 한다. 제안하는 알고리즘과 기존 알고리즘간의 비교 실험은 제안하는 알고리즘이 목표 비트량과 일치하는 결과 비트를 생성하며 동시에 PSNR 성능에서 기존의 알고리즘 보다 우수함을 보여준다.

• 대한전기학회논문지:전력기술부문A
• /
• 제48권6호
• /
• pp.760-772
• /
• 1999

The CAN is a serial communication protocol for distributed real-time control and automation systems. Data generated from field devices in the distributed control of power plant are classified into three categories: real-time event data, real-time control data, non-real-time data. These data share a CAN medium. If the traffic of the CAN protocol is not efficiently controlled, performance requirements of the power plant system could not be satisfied. This paper proposes a bandwidth allocation algorithm that can be applicable to the CAN protocol. The bandwidth allocation algorithm not only satisfies the performance requirements of the real-time systems in the power plant but also fully utilizes the bandwidth of CAN. The bandwidth allocation algorithm introduced in this paper is validated using the integrated discrete-event/continuous-time simulation model which comprises the CAN network and distributed control system of power plant.

• 제어로봇시스템학회논문지
• /
• 제13권3호
• /
• pp.230-234
• /
• 2007

Generally, huge amounts of data traffic are generated by using broadcasting method to deliver sensing data to a sink node reliably so that it makes a severe network saturation problem resulting in unreliable data transfer. In order to handle this problem, a new congestion control protocol is required for supporting reliable data transfer, minimal use of energy and network resources at the same time in wireless sensor networks. In this paper, it proposes a Protocol to guarantee both a reliable transfer in data accuracy and minimum consumption of energy waste by using Hop-by-Hop sequence number and DSbACK(Delayed and Selective ACK Buffer Condition) scheme. In addition, it proves that reliability and energy efficiency are enhanced by the proposed method with the simulation results performed on TinyOS platform which is a component based built-in OS announced by UC Berkely with the performance comparison of other existing methods.

• 전자공학회논문지A
• /
• 제32A권9호
• /
• pp.1219-1228
• /
• 1995

In this paper, we propose a dynamic bandwidth allocation scheme for the transmission of VBR video source through ATM based BISDN. In order to efficiently evaluate the required bandwidth, the characteristics of the VBR video sources generated by the MPEG coder are analyzed with variations in the number of GOP and quantizer scale. The required bandwidth for VBR video source is estimated by a prediction algorithm using scene and frame correlations as well as the statistical properties of the VBR video source. Scene correlation represents a strong correlation among the adjacent slices in a frame, and frame correlation represents a strong correlation among the frames. The statistical properties based on the traffic parameters of video sources such as peak rate, average rate, and standard deviation of source are determined through simulation. The performance of the proposed bandwidth allocation scheme is evaluated in terms of the over-allocated bandwidth, bandwidth utilization, and cell loss rate with variations in the quantizer scale and the number of GOP. It is shown that the results of simulation based on the proposed scheme are superior to those of the conventional methods.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2006년도 정기 학술대회 논문집
• /
• pp.772-777
• /
• 2006

An acoustic finite element model of a bridge is developed to evaluate the noise generated by the traffic-induced vibration of the bridge. The dynamic response of a multi-girder bridge, modeled by a 3-dimensional frame element model, is analyzed with a 3-axle(8DOF) truck model and a 5-axle(l3DOF) semi-trailer. The flat plate element is used to analyze the acoustic pressure due to the fluid-structure interactions between the vibrating surface and contiguous acoustic fluid medium. The radiation fields of noise with a specified distribution of vibrating velocity and pressure on the structural surface are also computed using the Kirchhoff-Helmholtz integral. In an attempt to illustrate the influence of the structural vibration noise of a bridge to total noise level around the bridge, the random function is used to generate the vehicle noise source including the engine noise and the rolling noise interacting between the road and tire. Among the diverse parameters affecting the dynamic response of bridge, the vehicle velocity, the vehicle weight, the spatial distribution of the road surface roughness, the stiffness degradation of the bridge and the variation of the air temperature changing the air density are found to be the main factors that increase the level of vibration noise. Consequently, The amplification rate of noise increases with the traveling speed and the vehicle weight.

• 한국도로학회논문집
• /
• 제19권3호
• /
• pp.65-70
• /
• 2017

PURPOSES : Pavement Management System contains the data that describe the condition of the road. Under limited budget, the data can be utilized for efficient plans. The objective of this research is to develop a mixed integer program model that maximizes remaining durable years (or Lane-Kilometer-Years) in road maintenance planning. METHODS : An optimization model based on a mixed integer program is developed. The model selects a cluster of sectors that are adjacent to each other according to the road condition. The model also considers constraints required by the Seoul Metropolitan Facilities Management Corporation. They select two lanes at most not to block the traffic and limit the number of sectors for one-time construction to finish the work in given time. We incorporate variable cost constraints. As the model selects more sectors, the unit cost of the construction becomes smaller. The optimal choice of the number of sectors is implemented using piecewise linear constraints. RESULTS : Data (SPI) collected from Pavement Management System managed by Seoul Metropolitan City are fed into the model. Based on the data and the model, the optimal maintenance plans are established. Some of the optimal plans cannot be generated directly in existing heuristic approach or by human intuition. CONCLUSIONS:The mathematical model using actual data generates the optimal maintenance plans.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2013년도 춘계학술대회
• /
• pp.601-603
• /
• 2013

본 논문은 Ad-hoc 네트워크에서의 전송을 효율적으로 하기 위한 클러스터링 알고리즘에 대해 실험을 통하여 살펴보았다. Ad-hoc 네트워크상 노드들은 정보전송과 위치등록, 노드간의 라우팅 경로유지를 위해 많은 패킷전송이 이루어진다. 본 논문에서는 무선 Ad-hoc 통신망에서 요구되는 알고리즘 프로그램개발을 통하여 패킷 전송효율을 분석을 통해 문자메세지, 무료통화가 가능한 알고리즘을 개발하여 향후 통신 서비스 산업에 적용가능함을 제시한다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2012년도 추계학술대회
• /
• pp.623-625
• /
• 2012

본 논문은 Ad-hoc 네트워크에서의 전송을 효율적으로 하기 위한 클러스터링 알고리즘에 대해 실험을 통하여 살펴보았다. Ad-hoc 네트워크상 노드들은 정보전송과 위치등록, 노드간의 라우팅 경로 유지를 위해 많은 패킷전송이 이루어진다. 이러한 환경에서의 트래픽은 고정망에서 보다 이동성 변수에 따라 더욱 많은 수가 발생하게 될 것이다. 본 논문에서는 무선 Ad-hoc 통신망에서 요구되는 알고리즘프로그램을 통하여 패킷 전송효율을 분석하여 그 결과를 제시한다.

• Journal of Information Processing Systems
• /
• 제12권4호
• /
• pp.711-723
• /
• 2016

With the rapid development of both ubiquitous computing and the mobile internet, big data technology is gradually penetrating into various applications, such as smart traffic, smart city, and smart medical. In particular, smart medical, which is one core part of a smart city, is changing the medical structure. Specifically, it is improving treatment planning for various diseases. Since multiple treatment plans generated from smart medical have their own unique treatment costs, pollution effects, side-effects for patients, and so on, determining a sustainable strategy for treatment planning is becoming very critical in smart medical. From the sustainable point of view, this paper first presents a three-dimensional evaluation model for representing the raw medical data and then proposes a sustainable strategy for treatment planning based on the representation model. Finally, a case study on treatment planning for the group of "computer autism" patients is then presented for demonstrating the feasibility and usability of the proposed strategy.

• 한국소음진동공학회논문집
• /
• 제22권2호
• /
• pp.156-162
• /
• 2012

This paper presents differences of road traffic noise maps were generated by using the draft map and two digital maps with different versions. As a first step, the calculation of the areas of excessive noise exposure was made for the draft map and each digital map version. Subsequently, the areas of excessive noise exposure were compared so as to determine how different from each other. Then, comparison of the populations exposed to excessive noise was also conducted in the same way. It was found that the most accurate noise map was obtained when using the combination of the draft map containing all attribute information and the digital map Ver 2.0. This result indicates that more information on the height and the number of floors of the individual building is required in order to obtain more accurate population exposed to excessive noise, thus creating a more accurate noise map.