• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.1
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• pp.26-33
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• 2018

A web application running on the Internet is causing many difficulties for a program developer, and it requires to process multiple sessions at the same time due to the occurrence of excessive traffic. Web applications should be able to process concurrent requests efficiently and in real time. Node.js is a single-threaded server-side JavaScript environment implemented in C and C ++ as one of the latest frameworks to implement event models across the entire stack. Nodes implement JavaScript quickly and robust to achieve the best performance using a JavaScript V8 engine developed by Google. In this paper, it will be explained the operation principle of Node.js, which is a lightweight real-time web server that can be implemented in JavaScript for real-time responsive web applications. In addition, this application was practically implemented through automatic alignment system for group scheduling to demonstrate event-based real-time response web processing.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1288-1290
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• 2007

Congestion in WSN increases energy dissipation rates of sensor nodes as well as loss of packets and thereby hinders fair and reliable event detections. We find that one of the key reasons of congestion in WSN is allowing sensing nodes to transfer as many packets as possible. This is due to the use of CSMA/CA that gives opportunistic media access control. In this paper, we propose an energy efficient congestion avoidance protocol that includes source count based hierarchical and load adaptive medium access control. Our proposed mechanism ensures load adaptive media access to the nodes and thus achieves fairness in event detection. The results of simulation show our scheme exhibits more than 90% delivery ratio with retry limit 1, even under bursty traffic condition which is good enough for reliable event perception.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.266-269
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• 2008

Urban is more intelligent continuously with the help of the convergence with IT technology. And it requires an integrated control system, which can manage urban facilities or monitor large-scale events based on GIS data, to provide its citizen with various ubiquitous services such as u-Health, u-Traffic, context-awareness etc. In order to realize the intelligent city geo-sensors that have the functionalities of generic sensing as well as location awareness will be established everywhere in the near future. Our system we presented have a rule engine to handle a atomic event as well as complex events that contain control flow or branch among them. And it can allow for visualization and monitoring the results through KML (Keyhole Mark-up Language) in the Google Maps. This paper describes au-GIS event processing system that can deal effectively with u-GIS events coming from various geo-sensor data in ubiquitous computing environments.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.669-672
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• 2000

회선분배장치를 제어관리하는 W/S의 Daemon 중에서 Event 처리를 담당하는 EvtProc Daemon의 경우를 들어 효율적인 부하 분산 알고리즘을 설계하였다. 본 논문에서는 대량의 Event 발생 시 담당 프로세스가 연속적으로 fork, exec 하지 않고 일정시간 대기하므로써 fork 와 exec 의 오버헤드를 줄이고 같은 Op Code의 연이은 Event 발생에 대기중인 프로세스가 이를 처리함으로써 더욱더 오버헤드를 줄일 수 있다. 그리고 Event를 처리하는 Child 생성에 있어 주 Child 가 부하분산을 담당하게 함으로써 효율적이고 안정적으로 관리할 수 있는 방안을 제시하였고 이를 구현 분석하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.1061-1064
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• 2003

SIP(Session Initiation Protocol) 기반의 VoIP(Voice over IP) 시스템의 구성 요소에서 레지스트라(Registrar)는 사용자들의 Registration 정보들을 저장 및 관리하는 역할을 한다. 네트워크상에서 이 Registration 상태는 관리자의 정책 등에 따라 동적으로 변화하게 되므로 사용자는 변경는 상태 정보를 알 필요성이 생긴다. Registration Event Package는 UA(User Agent)가 Subscriber로서 Registration 상태의 변경에 대한 통지를 요청할 수 있고 알림(Notification)을 통해 얻을 수 있는 매커니즘를 제공한다. 본 논문에서는 SIP 환경에서 이러한 Registration Event Package를 구현하여 사용자가 동적으로 변화되는 Registration 상태 정보를 알림을 통해 받을 수 있도록 하였다.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1263-1271
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• 1999

This paper designs the performance analysis layer for the various performance analysis of parallel programs using event expressions are similar to the normal program language to analyze the events which display a dynamic state exchange of a program. The event expressions suggest operations for overloading and functions which are needed in performance analysis, such as a filtering operation, data format translation functions, performance analysis, static functions, and etc. By using the event expressions, the programmer can modify the event trace data to analyze the performance and analyze more easily and variously than the pre-developed tools.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.5
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• pp.93-102
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• 1997

Conventional expert systems have difficulties in the inference on time-varing situations because they don't have the structure for processing time related informations and rule representation method to describe time explicitely. Some expert systems capable of temporal reasoning are not applicable to the domain in which state changes happen by unpredictble events that cannot be represented by periodic changes of data. In this paper, an event based temporal reasoning method is proposed. It is capable of processing te unpredictable events, representing the knowledge related to event and time, and infering by that knowledge as well as infering by periodically time-varing data. The NEO/temporal, an temporal inference engine, is implemented by applying the proposed temporal reasoning situation assessment and decision supporting system is implemented to show the benefits of the proposed temporal information processing model.

• International Journal of Contents
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• v.10 no.4
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• pp.30-37
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• 2014

The current study was conducted to examine the temporal and spatial activation sequences related to morphosyntactic, semantic and orthographic-lexical sentences, focusing on the morphological-orthographic and lexical-semantic deviation processes in Korean language processing. The Event-related Potentials (ERPs) of 15 healthy students were adopted to explore the processing of head-final critical words in a sentential plausibility task. Specifically, it was examined whether the ERP-pattern to orthographic-lexical violation might show linear precedence over other processes, or the presence of additivity across combined processing components. For the morphosyntactic violation, fronto-central LAN followed by P600 was found, while semantic violation elicited N400, as expected. Activation of P600 was distributed in the left frontal and central sites, while N400 appeared even in frontal sites other than the centro-parietal areas. Most importantly, the orthographic-lexical violation process revealed by earlier N2 with fronto-central activity was shown to be complexes of morphological and semantic functions from the same critical word. The present study suggests that there is a linear precedence over the morphological deviation and its lexical semantic processing based on the immediate possibility of lexical information, followed by sentential semantics. Finally, late syntactic integration processes were completed, showing different topographic activation in order of importance of ongoing sentential information.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.199-205
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• 2008

The centralized conference model has advantage of conference management and control. however it's scalability has been limited as performance degrades largely with increasing number of conference users. So new distributed conference models which improve scalability of centralized conference model have been suggested recently. In the distributed conference model. as conference users exceed a predefined maximum number, a new conference server is added to the conference dynamically. In this paper, We have proposed a new method which increases efficiency of conference event package processing that primary conference server should charge in the distributed conference environment. The primary conference server exchanges informations with each secondary conference servers and conference users by using conference event package. And from the conference information database it selects SIP(Session Initiation Protocol) UA(User Agent) which will share notification to the conference users, and transfers lists to each conference servers. The conference servers make the selected UAs share processing of conference event package, so loads of SIP signal processing decrease, and improve scalability of distributed conference model. The performance of our proposed model is evaluated by experiments.

• The Transactions of the Korea Information Processing Society
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• v.4 no.10
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• pp.2544-2552
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• 1997

This paper presents three multiprocess models for parallel protocol implementation, that is, (1)channel communication model, (2)fork-join model, and (3)event polling model. For the specification of parallelism for each model, a parallel programming language, Par. C System, is used. to measure the performance of multiprocess models, we implemented the Internet Protocol Suite(IPS) Internet Protocol (IP) for each model by writing the parallel language on the Transputer. After decomposing the IP functions into two parts, that is, the sending side and the receiving side, the parallelism in both sides is exploited in the form of Multiple Instruction Single Data (MISD). Three models are evaluated and compared on the basis of various run-time overheads, such as an event sending via channels in the parallel channel communication model, process creating in the fork-join model and context switching in the event polling model, at the sending side and the receiving side. The event polling model has lower processing delays as about 77% and 9% in comparison with the channel communication model and the fork-join model at the sending side, respectively. At the receiving side, the fork-join model has lower processing delays as about 55% and 107% in comparison with the channel communication model and the event polling model, respectively.