• International Journal of Highway Engineering
• /
• v.11 no.3
• /
• pp.129-139
• /
• 2009

The transportation network is a critical infrastructure in the event of natural and human caused disasters such as rainfall, snowfall, and terror and so on. Particularly, the transportation network in an urban area where a large number of population live is subject to be negatively affected from such events. Therefore, efficient traffic operation plans are required to assist rapid evacuation and effective detour of vehicles on the network as soon as possible. Recently, ubiquitous communication and sensor network technology is very useful to improve data collection and connection related emergency information. In this study, we develop a specific algorithm to provide evacuation route and detour information only for vehicles under emergency situations. Our algorithm is based on shortest path search technique and dynamic traffic assignment. We perform the case study to evaluate model performance applying hypothetical scenarios involved terror. Results show that the model successfully describe effective path for each vehicle under emergency situation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.9
• /
• pp.6260-6268
• /
• 2015

In LTE-Advanced that different networks coexist, it is considered that it is actually difficult to provide service continuity with a procedural and static control method applied to the existing voice service. This paper suggests Service Self-Organization to support the service continuity effectively based on SON. It means a method in which a subscriber's terminal collects information about its current condition and base station around, and a base station, through the data collected by monitoring inner or adjacent base station, shares related data and converges, controlling service continuity on its own. In other words, as context information of mobile terminal and base station changes, set-up of related functions such as ISHO, cell selection, source allocation, load control, and QoS mapping is adapted; each function fits into the change, exchanges the process of reorganization, and interacts; these actions go toward to satisfy service continuity. Simulation results show that it provides better performances than the conventional one with the measure of resource utilization rate and outage probability.

• 한국HCI학회:학술대회논문집
• /
• 2006.02a
• /
• pp.1194-1200
• /
• 2006

사용자-제품 상호작용(User-product interaction)의 관점에서 사용자의 만족도는 제품의 사용편의성(Usability)과 감성품질에 의해서 결정된다. 특히, 물리적으로 사용자와 제품의 기능을 연결하는 PUI(Physical User Interface)의 감성품질은 시각뿐 아니라 촉감, 동작감, 청감 등의 사용자의 다양한 감성의 조합으로 이루어져 있다. 문헌조사에 의하면, 사용자의 감성 만족도를 향상시키기 위한 제품의 시각적 감성품질에 관련된 연구는 활발하게 진행되고 있으나, 촉감, 동작감, 청감 등의 감성품질에 관련된 연구는 상대적으로 미흡한 실정이다. 이러한 관점에서 제품의 전체적인 감성품질을 평가하기 위해서는 제품과 사용자가 상호작용하는 PUI의 전반에 대한 사용자 만족도(User Satisfaction)의 정량적인 평가가 필수적이며, PUI의 감성품질을 구성하는 시각에 대한 고려뿐만 아니라, 예를 들어 조작장치를 잡는 느낌, 조작장치가 움직일 때의 동작감, 조작장치 작동 시의 청감 등 사용자와 조작장치 간에 일어나는 상호작용 전반에 관한 연구가 이루어져야 한다. 본 연구에서는 PUI의 구성요소 중 동적인 조작장치의 촉감, 동작감, 청감에 대하여 문헌 조사를 통해 조작 장치의 감성을 구성하는 요소들을 체계적으로 파악하였고, 감성의 요소를 중복 설명하지 않는 상호독립적인 의미를 가진 감성 형용사를 수집하고 분류한 후, 추출한 형용사를 기초로 설문지를 작성하였으며, 사용자들의 설문을 통하여 자료를 수집하였다. 구조방정식 기법을 사용하여, 조작장치의 전체적인 사용자 만족도와 촉감, 동작감, 청감 간의 상관관계 모형을 수립하였다. 또한 구조방정식의 결과를 바탕으로 인간공학 전문가와 제품설계 전문가로 이루어진 FGI(Focus Group Interview)를 실시하여 잡는 느낌, 동작감, 청감과 관련된 조작장치의 적절한 설계 변수를 결정한 후 설계값을 측정하였으며 감성 만족도와 측정치 간의 상관관계를 분석하여 감성품질 요소의 정량화를 수행하였다. 본 연구결과는 실제 산업현장에서 제품개발자들이 사용자 만족도에 영향을 미치는 제품 설계요소들의 상대적인 중요도를 평가하고, 감성품질을 결정하는 설계특성값을 구체적으로 파악하는데 실질적인 도움을 줄 것으로 기대된다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.35 no.9_10
• /
• pp.476-484
• /
• 2008

Most string problems and their solutions are relevant to diverse applications such as pattern matching, data compression, recently bioinformatics, and so on. However, there have been few works on the relations between string problems and cryptographic problems. In this paper, we consider the following string reconstruction problems and show how these problems can be applied to cryptography. Given a string x of length n over a constant-sized alphabet ${\sum}$ and a set W of strings of lengths at most an integer $k({\leq}n)$, the first problem is to find the sequence of strings in W that reconstruct x by the minimum number of concatenations. We propose an O(kn+L)-time algorithm for this problem, where L is the sum of all lengths of strings in a given set, using suffix trees and a shortest path algorithm for directed acyclic graphs. The other is a dynamic version of the first problem and we propose an $O(k^3n+L)$-time algorithm. Finally, we show that exponentiation problems that arise in cryptography can be successfully reduced to these problems and propose a new solution for exponentiation.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.15 no.5
• /
• pp.96-106
• /
• 2011

There are many advantages in applying gel propellant to a gel propulsion system. These include higher performances, the energy management of liquid propulsion system, reliable storability and low leakage characteristics. Additionally, gel propulsion system are preferable to the high density impulse of propulsion system. Also, when compared to liquid propellants, the gel propellants acquire greater heat energy. Gel propellants achieve a high specific impulse when metal particles with aluminum and boron are added. With respect to atomization, an inactive process occurs due to the variable viscosity of the metal particles and gelling agents. To improve the defect of atomization and combustion characteristics of gel propellant, a variety of issues related to spray and combustion is introduced here.

• The Journal of the Korea Contents Association
• /
• v.13 no.3
• /
• pp.109-118
• /
• 2013

The purpose of this study was to determine the effects of line dance programme on the balance ability during walking to reveal the exercise intervention for fall prevention. A 12-week line dance programme was applied to 18 elderly females who aged more than 65 years in the community. Balance ability during walking was evaluated by the range of center of pressure(cop), the velocity of cop, and free torque that calculated on the basis of ground reaction force data. The range and velocity of cop in the anterio-posterior were significantly reduced after performing(p<.01, p<.05, respectively), but change in those of cop in the medio-lateral and free torque were not found. It was demonstrates that 12-week line dance programme allows more effective in anterio-posterior stability of walking. It was suggested that the effect of fall prevention exercise should be studied more associate with fall frequency as future study.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2004.11a
• /
• pp.388-393
• /
• 2004

The organic law on the Construction Industry, initially, this law was enacted with a view to preserving and fostering the specialty of each type of industry. By dividing each construction business boundary, it gradually settles the system of construction specialized on the basis of productive stages. Controversy over the abolishing regulations on business boundary still continues to swirl. Since the intensity of exclusion as well as rigidities become increased. This results from the fact that informations are not shared among business boundary and businesses under the protection of the business boundary regulations choose 'rent-sicking activity'. According to dissidents against this law, structure should be established not by artificially enforced institution but by voluntary efforts of participants in construction industry. This paper aims at improving the competitive of the construction industry by showing the efficient system of construction and proving the legitimacy of abolishing business boundary

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.4
• /
• pp.311-320
• /
• 2021

A study is performed for the real time fault diagnosis during operation and health estimation relating to performance deterioration in a turbojet engine used for an unmanned air vehicle. For this study the real time dynamic model is derived from the transient thermodynamic gas path analysis. For real fault conditions which are manipulated for the simulation, the detection techniques are applied such as Kalman filter and probabilistic decision-making approach based on statistical hypothesis test. Thereby the effectiveness is verified by showing good fault detection and isolation performances. For the health estimation with measurement parameters, it shows using an assumed performance degradation that the method by adaptive Kalman filter is feasible in practice for a condition based diagnosis and maintenance.

• Journal of The Korean Association of Information Education
• /
• v.5 no.3
• /
• pp.432-442
• /
• 2001

It is necessary to Self Directed Astronomy Learning based on web to bring up individuality and creativity. Accordingly, the contents of this study is constructed by Astronomy which connects with our life but unable to observe actually. The contents is dynamic animation for learner's interest. The learners are able to decide their grade for themselves through the on-line evaluation according to their precedence learning. The Learner is able to evaluate by multiple-choice provide feedback by realtime. The contents is learned by themselves and introduced by the familiar contents in the real life, that is presented as the subject of experiment or observation connected with learning contents in the life.

• Journal of KIISE:Databases
• /
• v.29 no.5
• /
• pp.404-415
• /
• 2002

In this paper, we address the issue of ensuring consistency of multiple data items requested in a certain order by read-only transactions in a wireless data broadcast environment. To handle the inherent property in a data broadcast environment that data can only be accessed strictly sequential by users, we explore a predeclaration-based query optimization and devise two practical transaction processing methods in the context of local caching. We also evaluate the performance of the proposed methods by an analytical study Evaluation results show that the predeclaration technique we introduce reduces response time significantly and adapts to dynamic changes in workload.