• Journal of Information Technology Services
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• v.10 no.3
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• pp.237-250
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• 2011

Recently, Wireless Sensor Networks (WSN) require energy performance and guaranteed delivery delay time, contrarily with previous MAC protocols that aim to high throughput mostly. In order to satisfy the new significant requirements, many MAC protocols of WSN employ and try to enhance the duty cycle mechanism which is energy efficient technique in MAC layer. This duty cycle mechanism is oriented by toggling the transceiver conditions composed of wakeup and sleep states. The synchronous MAC protocols perform the period synchronization process. Hence, these are energy efficient in periodic monitoring environment, but are inefficient in where an event is incurred rarely and infrequently. Otherwise, the performance of asynchronous MAC protocols are contrarily with synchronous protocols. In this paper, we design two models consisting Always-busy and Always-idle ti simplify the general network congestion conditions. Through these models, moreover, we analyze two types MAC protocols in terms of energy efficiency and delay performance by analytical results. Additionally, we also evaluate two MAC protocols with two gongestion models that we designed. By the analytical and simulated results, we provide the general and efficient decision method in which protocols are more appropriate in a certain WSN environment.

• Journal of Welding and Joining
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• v.14 no.6
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• pp.119-130
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• 1996

Welding is one of the important technologies in shipbuilding industry. Automation and productivity promotion of welding contribute to the cost saving of ship production. The quality and productivity of welding are dependent on the quality and suitability of technical information supplied by engineering parts. This paper describes the research results of welding information system for ship. The system can be used for the development of CIMS for shipbuilding. For this work, the welding information related to the ship Production were analyzed in detail. Object-oriented technique is applied to represent the complex and various welding information. To process the extend amount of the welding information of ship, database system was constructed. A pilot system for the bulk carrier ship was developed and can be used with ease by programming of event-driven method and implementaion of graphical user interlace.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.185-190
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• 1995

Conventional alarm system has many difficulties in the operator's identifying the plant status during special situations such as design basis accidents. To solve the shortcomings, an on-line alarm annunciator system, called dynamic alarm console (DAC), was developed. In the DAC, a signal is generated as alarm by the use of an adaptive setpoint check strategy based on operating mode, and time delay technique is used not to generate nuisance alarms. After alarm generation, if activated alarm is a level precursor alarm or a consequencial alarm, it would be suppressed, and the residual alarms go through dynamic prioritization which provide the alarms with pertinent priorities to the current operating mode. Dynamic prioritization is achieved by going through the system- and mode-oriented prioritization. The DAC has the alarm hierarchical structure based on the physical and functional importance of alarms. Therefore the operator can perceive alarm impacts on the safety or performance of the plant with the alarm propagation from equipment level to plant functional level. In order to provide the operator with the most possible cause of the event and quick cognition of the plant status even without recognizing the individual alarms, reactor trip status tree (RTST) was developed. The DAC and the RTST have been simulated with on-line data obtained from the full-scope simulator for several abnormal cases. The results indicated that the system can provide the operator with useful and compact information fur the earlier termination and mitigation of an abnormal state.

• Journal of Korea Multimedia Society
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• v.23 no.5
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• pp.673-682
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• 2020

Buildings are becoming more and more high-rise and large-scale in recent years, so in the event of a disaster such as a fire, enormous human and economic damage is expected. Therefore, management, security, and fire control are essential for large buildings in the city. Because these large buildings are very complex outside and inside, they need a three-dimensional control based on 3D modeling rather than a simple flat-oriented control. To do this, this paper designed and implemented a building control system based on 3D modeling. Specifically, we designed a 3D building / facility editing module for 3D modeling of buildings, a 3D based control module for building control, and a linkage module that connects information such as firefighting equipment, electrical equipment and IoT equipment. Based on this design, a building control system based on 3D modeling was implemented.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.12
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• pp.2140-2150
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• 2006

The RSS Reader is a software application that assist users easily to read and collect contents which are frequently changeable syndicated contents of RSS format that published on the web. This paper presents a formula software design based on RUP object-oriented design method for implementing the RSS Reader. We extract a use case based on requirements for implement of the RSS Reader and propose a domain concept model by. Using above artifacts, we extract event to generate between users and, the RSS Reader and logical architecture. So, we design classes and packages of the RSS Reader. As proposed a formula software design about the RSS Reader in early stage, it can make the RSS Reader with a variety of characters easily based on these.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.6
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• pp.672-677
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• 2010

Recently, the efficient management system for large-scale sensor data has been required due to the increasing deployment of large-scale sensor networks. In this paper, we propose a cloud-based sensor data management system with low cast, high scalability, and efficiency. Sensor data in sensor networks are transmitted to the cloud through a cloud-gateway. At this point, outlier detection and event processing is performed. Transmitted sensor data are stored in the Hadoop HBase, distributed column-oriented database, and processed in parallel by query processing module designed as the MapReduce model. The proposed system can be work with the application of a variety of platforms, because processed results are provided through REST-based web service.

• Journal of Applied Reliability
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• v.15 no.2
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• pp.108-123
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• 2015

Test and Evaluation (T&E) have been verifying the level of it's technological skill and the needed operational status of the development weapons. If the overall spectrum of test and evaluation is fulfilled substantially in the production & deployment, the needed level of the weapon system will be enhanced and also the reliability status will become higher considerably. We can know currently these issues through the mass media and all kinds of the news regarding the defense industry and programs. And so this article have studied the method of enhancing reliability of the test and evaluation, the 6 variables were selected through the discussion of the professional group. The the test and evaluation group needs consistently the professional training systems. After DT&E, we have to the event to verify the technical level of the development systems. We have to take the high level of the kinds of the environmental test. Scientific methods like system engineering will be adapted in process of the test and evaluation. The number of suitable test prototype in the test and evaluation is analysed more systematically. And we need to establish the standardization of the test and evaluation. If 6 variables are well analysed and adapted in the working field, the reliability of the test and evaluation will be considerably, the defense industry will take the chance to develope the future-oriented.

• Earthquakes and Structures
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• v.13 no.3
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• pp.323-335
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• 2017

A simplified framework for the probabilistic estimation of economic losses induced by the structural vulnerability in single-story and single-bay precast industrial buildings is presented. The simplifications introduced in the framework are oriented to the definition of an expeditious procedure adoptable by government agencies and insurance companies for preliminary risk assessment. The economic losses are evaluated considering seismic hazard, structural response, damage resulting from the structural vulnerability and only structural-vulnerability-induced e]conomic losses, i.e., structural repair or reconstruction costs (stock and flow costs) and content losses induced by structural collapse. The uncertainties associated with each step are accounted for via Monte Carlo simulations. The estimation results in a probabilistic description of the seismic risk of portal-like industrial buildings, expressed in terms of economic losses for each occurrence (i.e., seismic event) that owners (i.e., insured) and stakeholders can use to make risk management decisions. The outcome may also be useful for the definition of the insurance premiums and the evaluation of the risks and costs for the owner corresponding to the insurance industrial costs. A prototype of a precast concrete industrial building located in Mirandola, Italy, hit by the 2012 Emilia earthquake, is used as an example of the application of the procedure.

• Journal of the Korean Society of Costume
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• v.51 no.6
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• pp.147-165
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• 2001

Haute couture denotes a luxurious made-to-order dressmaker's shop. In principle, it refers to a place that is registered with the Paris Apparel Association and has met the size and criteria specified by the association. The features of modern fashion expressed in haute couture have been contemplated by categorizing them into mixed impression appearing in haute couture work pieces. turning the collection event into a spectacle and commercialization for the succession of haute couture. Mixed impression manifested in the haute couture has engendered (1) the creative and dynamic feature (2) eclecticism with popular culture (3) mixed impression of reactionism (4) ethnic characteristics. From the above considerations, one could say that the factors drive the very existence of haute couture and comprise three elements of impeccable backgrounds, They are (1) organizing ability and protective policies of the French fashion industry, (2) relentless experimental spirit of the haute couture designers and (3) Paris that supports creativity and fashion fabrication, have coincided with rising up of the value of persistence on originality of work pieces in accordance with diversifying cultural transformations. consumer-oriented patterns by way of capital symbolized by consumers and restructuring of company operation by each shop. This report describes comprehensive understanding of haute couture, creativity and dynamic power of the haute couture work pieces. Akin to the efforts to maintain the existence of high-grade cultures throughout the overall cultures themselves, haute couture, on the basis of these factors, should also become the motive power through which luxurious culture in fashion is created in the days ahead.

• Journal of the Korea Society for Simulation
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• v.11 no.2
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• pp.1-16
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• 2002

The need for network security is being increasing due to the development of information communication and internet technology. In this paper, firewall models, operating system models and other network component models are constructed. Each model is defined by basic or compound model, referencing DEVS formalism. These models and the simulation environment are implemented with MODSIM III, a general purpose, modular, block-structured high-level programming language which provides direct support for object-oriented programming and discrete-event simulation. In this simulation environment with representative attacks, the following three attacks are generated, SYN flooding and Smurf attack as an attack type of denial of service, Mail bomb attack as an attack type of e-mail. The simulation is performed with the models that exploited various security policies against these attacks. The results of this study show that the modeling method of packet filtering system, proxy system, unix and windows NT operating system. In addition, the results of the simulation show that the analysis of security performance according to various security policies, and the analysis of correlation between availability and confidentiality according to security empowerment.