• Journal of KIISE:Information Networking
• /
• v.34 no.6
• /
• pp.493-504
• /
• 2007

With the advance and proliferation of computer and wireless network technology, it is common to access to network through the wireless network using mobile device. The ratio of using the streaming media out of many applications through the network is increasing not only in the wired network but also in the wireless network. The streaming media is much bigger than other contents and requires more network bandwidth to communicate and more computing resources to process. However the mobile devices have relatively poor computing resource and low network bandwidth. If the streaming media service is provided for mobile devices without any consideration about the network bandwidth and computing power, it is difficult for the client to get the service of high quality. Since especially mobile devices are supported with very limited energy capacity from the battery, the streaming media service should be adjusted to the varying energy state of mobile devices to ensure the complete playback of streaming media. In this paper, we propose a new method to guarantee the complete playback time of the streaming media for the mobile clients by dynamically controlling transmitted frame rate to the client according to the estimated available time of mobile device using battery model reflecting the characteristic of the battery. Since the proposed method controls the number of frames transmitting to the client according to the energy state of the mobile device, the complete playback time is guaranteed to mobile clients.

• KIISE Transactions on Computing Practices
• /
• v.23 no.12
• /
• pp.651-659
• /
• 2017

IT(Information Technology) has focused on infrastructure-technologies in the past but now focuses on IT service. Many companies strive to save costs and improve IT services. For this reason, they strive to implement a good internalization of ITSM (IT Service Management) by developing ITSM systems based on ITIL (Information Technology Infrastructure Library) from the late 2000s. In particular, IT service operations are one of the structure elements of ITIL version 3 and are highly related to the internalization of ITSM. However, in spite-of-the successful implementation of ITSM, the efficiency of IT service management has not improved due to iterative issues. Therefore, this study developed a user-centered training system by defining the iterative issue guidelines and implementing a database. The implemented user-centered training system provided IT service users with regular training services to produce a good solution for iterative issues after connecting the operation part of the ITSM system. Based on the results of this study, we expect that the proposed ITSM system will contribute to efficiently managing IT services by improving the limitations of IT service operation in the ITSM system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.324-325
• /
• 2016

The sensor network-based service collects data by using the sensor, the data is aware of the situation via the analysis, and the service provider provides a service suitable for the user via the context-awareness. However, this data is generated, it is difficult to match the metadata and standard units. The data integration is required to use the data generated by the different specifications of the sensor efficiently. Accordingly, in this paper we propose a method using an ontology as a method to integrate the data generated by the existing sensors and the new sensor. The ontology is mapping to the standard item and sensors, also include a type and structural difference. The mapping is comprised of two:data mapping, and metadata mapping. There are standard items that are created in this way, type of data exchange between services. This can solve the heterogeneous problem generated by sensors.

• Annual Conference of KIPS
• /
• 2008.05a
• /
• pp.796-799
• /
• 2008

최근 유비쿼터스 컴퓨팅과 유비쿼터스 네트워크를 활용하여 새로운 서비스들을 개발하려는 노력이 진행 중이며, 이와 관련된 기술의 중요성도 급증하고 있다. 특히 감시정찰 센서네트워크의 핵심 구성요소인 저가의 경량 센서노드에서 측정한 미가공 데이터(raw data)를 사용하여 침입 물체의 실시간 탐지, 식별, 추적 및 예측하기 위한 디지털 신호처리 기술은 주요 기술 중 하나이다. 본 논문에서는 감시정찰 센서네트워크의 핵심 구성요소인 소리센서 노드에서 측정한 소리 미가공 데이터를 사용하여 차량을 탐지할 수 있는 소리센서 디지털 신호처리 알고리즘을 설계 및 구현 한다. 알고리즘의 주 목표는 감시정찰용 센서노드의 탐지 신뢰성을 높이기 위한 높은 침입물체 탐지 성공률(success rate)과 낮은 허위신고(false alarm) 횟수를 가지는 것이다. 성능평가 결과에 의하면 제안한 AMIDA 알고리즘은 90% 이상의 탐지 성공률과 2 회 이하의 허위신고 횟수를 가지는 것을 확인할 수 있었다.

• Journal of the Health Care and Life Science
• /
• v.11 no.1
• /
• pp.67-77
• /
• 2023

This paper aims as a prior study to cultivate artificial intelligence professionals at the level of colleges in the future by analyzing healthcare services and technologies using artificial intelligence technology. As artificial intelligence technology is recognized as a key engine or core technology in the future that will create national competitiveness and added value, advanced countries are investing a lot of attention and support in developing technologies as well as human resources at the national level. Korea is also promoting national-level R&D manpower training projects such as AI graduate program support projects, and investing heavily in fostering and securing its own artificial intelligence personnel, mainly by large companies, but there is a lack of artificial intelligence experts. This study analyzes the current status of healthcare services and technologies, industries, and artificial intelligence manpower training using artificial intelligence technology, and proposes directions for fostering artificial intelligence personnel at the level of colleges.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.23 no.6
• /
• pp.1169-1180
• /
• 2013

Emulab is a research framework developed by Utah university, proving on-demend research environment service so that researchers can set up and use the environment at anytime. The main advantage of Emulab over other research methodologies like simulation or virtualization is to use real systems and networks using real operating systems, making the research environment much similar to the real world. Even though Emulab has been actively used in many areas such as security and network, there has been little use in Korea research community. As KISTI recently constructed a small Emulab, it is expected that many researchers and educators would make use of the Emulab. In this study, we introduce Emulab to Korea research community and give an overview of utilization trend of Emulab as a cyber security research framework.

• Journal of KIISE
• /
• v.45 no.3
• /
• pp.303-310
• /
• 2018

LoRaWAN(Long Range Wide Area Network) is a standard for low-power, long-range, low-speed communication as announced in the LoRa Alliance. LoRaWAN addresses the physical layer and medium access control layer and the technology used in the physical layer is referred to as LoRa. LoRa can be used for remote monitoring and remote control in maritime conditions. However, unlike land, marine environment is not only difficult to construct an infrastructure for service provision, but also difficult to analyze LoRa performance in maritime. In this study, we construct an infrastructure using cloud platform and analyze LoRa link performance in maritime conditions.

• Journal of KIISE
• /
• v.43 no.11
• /
• pp.1223-1232
• /
• 2016

A virtual network technology can provide a network reflecting the requirements of various services. The virtual network can distribute resources of the physical network to each virtual slice. An efficient resource distribution technique is needed to reflect the requirements of various services. Existing bandwidth distribution techniques can only control downlink traffic without taking traffic conditions on the network into account. Downlink and uplink share the same resources in a wireless network. The existing bandwidth distribution techniques assumed that all stations generate saturated traffic. Therefore, the existing bandwidth distribution technique cannot make traffic isolation in a virtual wireless network. In this paper, we proposed a traffic-based bandwidth control techniques to solve these problems. We applied Software-Defined Networking(SDN) to the virtual wireless network, monitored the traffic at each station, and searched for stations that generated unsaturated traffic. We also controlled both uplink and downlink traffics dynamically based on monitoring information. Our system can be implemented with legasy 802.11 clients and SDN-enabled APs. After the actual test bed configuration, it was compared to existing techniques. As a result, the distribution performance of the proposed technique was improved by 14% in maximum.

• Journal of KIISE:Information Networking
• /
• v.27 no.1
• /
• pp.76-87
• /
• 2000

ATM is a key technology of integration of multimedia service. Recently, Many study have been concentrated on performance testing for evaluation network performance are stronger everyday. The performance testing is on evaluation of maximal throughput of network by measuring and analyzing of various performance parameters. There are two ways to test ATM network performance; one is using QoS in cell level on the point of network's view, and the other is using metric in frame level in the point of user's view. And, the standardization process is also under way. In this paper, we derive a performance requirement of TCP in TCP/IP data transmission over ATM UBR service. By applying the derived requirements to ATM and packet networks, we evaluate the performance of TCP over UBR based on the result of our simulations. Therefore, we evaluate the result of simulation and find degradation of network throughput by interaction between TCP congestion control and ATM cell drop policy. So we suggest the accelerated Vegas that modify traditional TCP Vegas in congestion control mechanism for batter network throughput.

• Journal of KIISE:Computing Practices and Letters
• /
• v.5 no.6
• /
• pp.771-781
• /
• 1999

오늘날의 컴퓨팅 환경은 통신 네트워크의 복잡성과 다양한 멀티미디어 서비스 처리를 위해 객체지향 기술을 분산 시스템에 도입하고 통신망을 소프트웨어 계층적 모델로 구조화한 개방형 정보 통신망 구조 연구가 활발히 진행되고 있다. 본 논문은 분산환경에서 멀티미디어 스트림 데이타를 전송하기 위한 아키텍쳐에 관한 모델의 설계 및 구현에 관한 것으로 분산 환경에서 멀티미디어 스트림 데이타를 효율적으로 전송할 수 있는 구조를 제시하고 있다. 설계한 구조는 Point-to-Point와 멀티캐스트를 지원하며 컴퓨터 통신망에서 멀티캐스트 연결을 효율적으로 관리하고 추후 기능 확장 및 기능 변경이 용이하도록 모듈화하고 유연성을 가지는 연결 관리 구조를 설계하고 구현하였다. 신호기능은 CORBA(Common Object Request Broker Architecture)의 ORB를 이용하여 실현하였으며, 데이타 전송 기능은 TCP/IP연결을 이용하였다. 이렇게 신호처리 부분과 데이타 전송 부분을 독립적으로 만들어서 하부망 기술에 독립적인 연결 관리 구조를 채택하고 있으므로 향후 다른 환경에서도 신호처리 부분을 그대로 적용할 수 있다. 분산 객체 개념을 적용하여 연결 관리 기능을 분산 객체화 하였으며 각 분산 객체간 인터페이스를 OMG(Object Management Group) IDL(Interface Definition Language)로 정의함으로써 유연성을 갖도록 하였다.AbstractThis paper proposes communication service architecture to support dynamic communication configuration and multiple connection management which are required to handle a variety of multimedia multicast application. Our communication service architecture was designed to fulfil the objectives as the following:- To build a common networking system for various multimedia multicast services- To build a platform for rapid service development and provisioning- To provide service networking independent on transport network technologiesWe implemented communication service architecture based on Common Object Request Broker Architecture (CORBA) for multimedia multicast applications. Our communication service architecture is distributed and object-oriented for extensibility and easy modification. The interfaces between the distributed objects are specified in (Object Management Group) OMGs Interface Definition Language.