• Journal of KIISE:Information Networking
• /
• v.28 no.3
• /
• pp.447-453
• /
• 2001

In this paper, we consider the scheduling of SE(switching element)-disjoint multicasting in photonic Banyan-type switching networks constructed with directional couplers. This ensures that at most, one connection holds each SE in a given time thus, neither crosstalk nor blocking will arise in the network. Such multicasting usually takes several routing rounds hence, it is desirable to keep the number of rounds(i.e., scheduling length) to a minimum. We first present the necessary and sufficient condition for connections to pass through a common SE(i.e., make crosstalk) in the photonic Banyan-type networks capable of supporting one-to-many connections. With definition of uniquely splitting a multicast connection into distinct subconnections, the crosstalk relationship of a set of connections is represented by a graph model. In order to analyze the worst case crosstalk we characterize the upper bound on the degree of the graph. The successor paper(Part II)[14] is devoted to the scheduling algorithm and the upper bound on the scheduling length. Comparison with related results is made in detail.

• Journal of Broadcast Engineering
• /
• v.9 no.1
• /
• pp.74-82
• /
• 2004

In digital broadcasting, applications are computer programs executed by the set-top box(TV receiver) , and synchronized applications are those that perform tasks at the specified moments in the underlying video. This paper describes important concepts, standards, and skills needed to implement synchronized applications and explains how to integrate them to implement these applications. This Paper assumes the European data broadcasting standard, DVB-MHP. In DVB-MHP, scheduled stream events are recommended as a means of synchronizing applications with video streams. In this method, the application receives each stream event, and executes the action associated with the stream event at the time specified in the stream event. Commercially available stream generators, i.e., multiplexers, do not generate transport streams that support scheduled stream events. So we used a stream generator implemented in our lab. We implemented a synchronized application where the actions triggered by stream events are to display graphic images. We found that our synchronized application processes scheduled stream events successfully. In our experimentation, the stream events were synchronized with the video and the deviation from the intended time was within 240 ㎳, which is a tolerance for synchronization skew between graphic images and video.

• Journal of KIISE:Computing Practices and Letters
• /
• v.10 no.4
• /
• pp.351-363
• /
• 2004

Recent commencement of digital broadcasting has enabled various TV programs through hundreds of channels. As a result, it becomes a time-consuming job for the TV audience to look up newspaper or TV magazines for the schedule of a specific TV program. To relieve this problem, digital broadcasting usually provides an EPG(Electronic Program Guide) for the audience. Currently. most EPG services are focusing on the visual delivery of information through a web site, digital TV or mobile devices. However, this approach could cause a serious restriction to some users including drivers or visually handicapped persons, who can't input keywords for the search. In order to solve this problem, in this paper, we propose a VoiceXML-based EPG retrieval system that enables even such special users to browse EPG. conveniently using a mobile phone. We implemented a prototype system and proved its effectiveness through experiments.

• Annual Conference of KIPS
• /
• 2005.11a
• /
• pp.839-842
• /
• 2005

웹 기반 교육에서 학습자의 완전통제에 의한 학습보다는 학습자의 특성에 따른 시스템과 상호작용 적응적 통제에 교육시스템이 요구된다. 교수자에 의해 제시되는 코스와 학습자 선택에 의한 동적 코스를 통한 학습시스템을 제안하였다. 새롭게 생성된 동적코스를 타 학습자에게 제시함으로써 교수자와는 다른 시각의 코스에 의한 학습 가능하도록 하여 학습자의 학습능력을 높일 수 있다. 본 연구를 통해 시스템과의 적응적 학습자 통제에 의한 보다 높은 학습 효과를 가져 올 것으로 기대된다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.9
• /
• pp.1386-1394
• /
• 1993

It has been very difficult and inefficient to implement data synchronization in the multimedia information systems until now, because most data synchronizations have been implemented by ad hoc methodologies. In this paper, we propose a new synchroniation methodology implemented by scheduling using monitor. If users definece the temporal relationships of media data using high level user interface, then the monitor selects media data started at that time and controls setup time and precessing time. The scheduler determines the scheduling method or selected media data and adjusts the synchronization among them.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.3
• /
• pp.707-714
• /
• 2015

The national government is pushing hard the adoption of the BIM (Building Information Modeling) technology in the construction industry. The BIM application provides a visualized environment where the construction manager can inspect the structure of buidling structures. The application also provides information on activity progresses as well as earned values. However, BIM is mostly applied to visualize a structural object with definite forms. The BIM technology needs to be extended to include an object with non-definite forms such as earthwork operations. The objective of this study is to present a prototype of earthwork BIM in the construction operation. The prototype has been built on the attributes of geological information, construction equipment and positioning. The prototype of earthwork BIM shows a 3D graphic simulation of construction equipment moving around for digging and loading.

• Annual Conference of KIPS
• /
• 2003.05a
• /
• pp.117-120
• /
• 2003

웹의 다양한 자원을 이용하여 고성능 작업 처리를 요구하는 분산/병렬 시스템은 균형적인 작업 할당을 위해 각 호스트의 성능 평가가 중요하다. 하지만 성능 평가에 대한 지속적인 신뢰하기가 어려우며 뿐만 아니라, 작업 도중 호스트의 성능 변화를 예측하기가 어렵다. 성능 변화에 따른 효율적인 작업 스케줄링이 필요하며, 자원 관리자는 작업을 수행중인 호스트에 대한 모니터가 요구된다. 본 논문에서는 자원 관리자와 시스템 관리자에게 효율적인 자원 정책을 제안하기 위해 각 호스트의 자원을 모니터하고, 분산/병렬 시스템의 작업 할당 메커니즘에 의해 각 호스트의 성능 평가 기준을 정한다 또한 관리자에게 실시간으로 호스트의 성능 변화에 따른 자원 정보를 관리하도록 다양한 시각화를 제공한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.2
• /
• pp.1-6
• /
• 2023

The purpose of this study is to research and develop so that users who are gradually progressing in the popularization of smartphones and the calculation of agricultural quality can use more active and flexible applications than existing application fields. People use event management applications to remember what they need to do, and maps applications to get to their appointments on time. You will need to build a glue-delivered application that leverages the Maps API to be able to recommend the glove's path for events so that the user can use the application temporarily. By comparing and analyzing currently used calendar, map, and schedule applications, several Open Maps APIs were compared to supplement the weaknesses and develop applications that converge the strengths. The results of application development by applying the optimal algorithm for recommending traffic routes according to time and place for the schedule registered by the user are described.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.565-568
• /
• 2003

Roadway construction planning processes involve a large amount of information on design, construction methods, quantities, unit costs, and production rates. GIS (Geographic Information System) is a strong tool for integration and managing various types of information such as spatial and non-spatial data required for roadway construction planning. This paper proposes a GIS-based system for improving roadway construction planning with its 'Spatial Analysis' and 'Visualization' functions. The proposed system cail help construction planner make a proper decision in a unique way by integrating design information and construction information within the system and creating design element modules for space scheduling purposes in real-time with its 'Interactive Planning' function.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1731-1737
• /
• 2007

This paper considers subway routing problem. Given a schedule of train to be routed by a railway stock, the routing problem determines a sequence of trains while satisfying turnaround time and maintenance restrictions. Generally, the solution of routing problem is generated from set partition formulation solved by column generation method, a typical integer programming approach for train-set. However, we find the characteristics of metropolitan subway which has a simple rail network, a few end stations and 13 departure-arrival patterns. We reflect a turn-around constraint due to spatial limitations has no existence in conventional railroad. Our objective is to minimize the number of daily train-sets. In this paper, we develop two basic techniques that solve the subway routing problem in a reasonable time. In first stage, we formulate the routing problem as a Min-cost-flow problem. Then, in the second stage, we attempt to normalize the distance covered to each routes and reduce the travel distance using our heuristic approach. Applied to the current daily timetable, we could find the subway routings, which is an approximately 14% improvement on the number of train-sets reducing 15% of maximum traveling distance and 8% of the standard deviation.