• Journal of Digital Convergence
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• v.10 no.9
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• pp.185-193
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• 2012

Korean's major firms made a slogan Smart Work as an important business strategy and tried to implement some activities. These Smart trends influenced the way people's working and organization. Based on the actual practices of Korean's major firms, we extract the smart-work supporting tools and practices, exploratory and exploitative activities as the important factors influencing the smart work performances. The statistical result, based upon survey responses, shows that exploratory and exploitative activities are the salient factors for smarkwork level, and that three types of he smart-work supporting tools and practices indirectly influence smarkwork level through exploratory and exploitative activities. As a conclusion, the academic and practical implications of these findings are also discussed.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.3_4
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• pp.130-137
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• 2003

This paper presents the problem of partitioning the Single-Stage Shuffle-Exchange Network(SSEN). An algorithm, named SSEN_to_PSEN, is devised to transform an SSEN into a Partitionable Shuffle-Exchange Network (PSEN). The proposed algorithm presents that the SSEN can be partitioned into independent sub-networks without additional links for N $\leq$ 8. Additional links are needed in order to partition an SSEN, but only when N $\geq$ 16. The running time of the algorithm SSEN_to_PSEN is $\theta$(NlogN). By comparing with a hypercube network, the PSEN is less expensive than a hypercube network even when some additional links are added. By partitioning, a large PSEN in a massively parallel machine can compute various problems for multiple users simultaneously, thereby the processing efficiency of the machine is improved.

• The KIPS Transactions:PartD
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• v.13D no.1 s.104
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• pp.139-146
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• 2006

This paper describes the design and implementation details of a distributed transactional workflow monitoring system. There have been prevalent research and development trends in the workflow literature - workflow systems tend to be completely distributed architectures to support very large-scale workflow applications on object-oriented and internet-based infrastructures. That is, the active (object), distributed (architecture), system-oriented (transaction), and large-scale (application) workflow systems are the key targets in terms of the research and development aspects. While the passive, centralized, human-oriented, and small/medium scale workflow systems are the typical instances of the traditional workflow systems. Unlike in the traditional (the client-server architecture) workflow systems, the workflow monitoring features should not be easily supported in the recent (the fully distributed architecture) workflow systems. At the same time, they need a set of additional monitoring features, such as gathering and displaying statistical (or overload status) information of the workflow architectural components dispersed on the internet. We, in this paper, introduce the additional workflow monitoring features that are necessarily required for the recent workflow systems, and show how to embed those features into a web-based distributed workflow system.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.185-189
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• 2009

무선 센서 네트워크는 화산 감시, 전장 감시, 동물 서식지 감시, 건축물의 감시, 농장 관리, 의료분야등 다양한 분야에서 연구되고 있다. 국내에서도 국가 정책 사업으로 교량 및 건축물의 균열 감시, 표적의 침입 탐지 및 식별을 위한 무선 센서 네트워크 연구가 활발히 진행 중이다. 특히, 무선 센서 네트워크의 다양한 분야의 연구 중에서 철조망을 이용한 표적의 침입 탐지 및 식별에 관한 연구는 산업 시설, 보안지역, 교도소, 군사지역, 공항 등 다양한 분야에서 사용된다. 현재 철조망 감시는 대부분 유선 센서 노드를 통한 유선 센서 네트워크 환경에서 이루어지고 있다. 기존의 유선 센서 네트워크는 높은 데이터 전송률을 통해 수신되는 높은 정보의 신호를 이용하여 고속 푸리에 변환에 의한 신호의 주파수 분석 기법을 사용해 왔다. 하지만, 유선 센서 네트워크의 높은 데이터 전송률과 비교하여 무선 센서 네트워크의 센서 노드는 유선 센서 네트워크에 비해 매우 낮은 데이터 전송률을 가진다. 따라서 무선 센서 네트워크에서 수신되는 신호의 정보가 매우 낮고, 유선 센서 네트워크에서 사용된 고속 푸리에 변환에 의한 신호의 주파수 분석에 따른 주파수별 특징 추출을 할 수 없다. 따라서 본 논문에서는 철조망 감시를 위한 높은 데이터 전송률을 보장하는 유선 센서 네트워크에 비해 제한된 통신자원과 센서 노드의 낮은 데이터 전송률로 인해 수신되는 한정적인 신호의 정보를 이용한 무선 센서 네트 워크에서 철조망의 표적 침입 탐지 및 식별을 위한 특징 추출 알고리즘을 제안한다.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.5_6
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• pp.214-227
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• 2007

A context-aware service in ubiquitous computing environments aims to supply services according to users' situation information that is dynamically occurring. The existing context-aware workflow systems, such as FollowMe and uFlow, provide context-aware services based on a workflow, which uses users' situation information as transition conditions of a service. But they can't apply users' new service demands, which may dynamically occur even when a workflow is on going, to a workflow scenario. In this paper we propose a context-aware workflow system, which can reapply users' new service demands into an initial workflow without interrupting or deleting the workflow. The proposed system can provide context-aware services without interrupting of service by recognizing exactly a place holder that has to be changed in a workflow scenario and by reconstructing only the changed parts through an incremental parsing method. Therefore, a user can immediately apply his new service demands to an on-going workflow scenario, and he can be guaranteed continuous executions of context-aware services according to a workflow scenario, which includes new service demands.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.77-88
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• 2010

Wireless Mesh Networks are consist of mobility mesh clients and mesh routers. WMNs can communicate with heterogeneous networks such as IEEE 802.11, IEEE 802.15, IEEE 802.16 and sensor networks. WMNs which is based on ad hoc network are on research and developing to enhance WLANs, WPANs, or WMANs. WMNs can offer environment to serve human, service to person area, campus, and metro. But WMNs has many problems to solve about enhancing performance and generalization. Among them, Existing protocol layers has many problems enhancing to optimize WMNs. This document issues problems about WMNs in protocol layer and suggest the solutions. Also, suggests the requirements and the methods of QoS supporting issue.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.5A
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• pp.391-400
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• 2009

Recently, cellular communication networks are migrating from 2G to 3G. Spectrum utilization tends to be inefficient during the transition. Cognitive radio (CR) technology can be a key solution to increase spectrum efficiency by allowing secondary networks to utilize frequency resource of primary networks. However, conventional CR approaches which do not utilize the frequency reuse factor of primary networks may incur degradation of whole network performance. In this paper, we propose a mechanism that a secondary network senses pilot signals of a primary network and select optimum frequency bands. In order to maximize whole network performance, we formulate an optimization problem subject to interference constraints for a primary network and present algorithms. Simulation results compare the proposed method with the conventional method. Our proposed method shows performance gain over the conventional method if channel variation of a primary network is dynamic and the frequency reuse factor of a primary network is high.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.901-908
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• 2010

There are many kinds of networks in vehicle for their purposes. In-vehicle networks, however, are not unified to single network. The networks are composed of several local networks because of communication speed, cost and efficiency. Because the complexity of network design for communication increases, local networks need a framework for interworking between heterogeneous networks. In this paper, a framework interworking between in-vehicle networks for ITS(Intelligent Transportation System) is proposed and implemented. The proposed framework consists of a compatible protocol, message conversion module, message transceiver module and message analysis module. The results obtained by implementation show that the framework efficiently supports the communication of information between heterogeneous in-vehicle networks.

• Journal of the Korea Society of Computer and Information
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• v.18 no.10
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• pp.121-128
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• 2013

Existing sensor network studies have only emphasized energy aspects that sensors themselves had. But when an actual sensor network is established, biased use of a specific sensor may cause a partial disconnection of the sensor network. It becomes an disadvantage to fail efficient operation of the sensor network for a long time and energy efficiency of specific sensor energy causes to drop the efficiency of the sensor network. When a sensor network is composed of many clusters or made up of a large network, sensor network's disconnection cannot be avoided because they emphasize sensor's energy efficiency. Therefore, it was tried to lengthen the lifespan of the sensor network by making sensors in the sensor network avoid disconnection through even use of all the sensors composing of the sensor network. This article proposes a protocol to maintain a sensor network for a long time by preventing a sensor networks' disconnection through efficient management of sensor network energy composed of the protocols composing of the sensor network in ubiquitous environments.

• Journal of Internet Computing and Services
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• v.16 no.5
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• pp.59-66
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• 2015

A stochastic modeling approach as a mathematical method for workflow intelligence is widely used for analyzing and simulating workflow models in the literature. In particular, as a resource-centric modeling approach, this paper proposes a stochastic model to represent work-handover relationships between performers in a workflow-supported social network. Calculating probabilities for the work-handover relationships are determined by two types of probabilities. One is the work-transition probability between activities, and the other is the task assignment probability between activities and performers. In this paper, we describe formal definitions of stochastic workflow models and stochastic work-handover relationship models, as well. Then, we propose an algorithm for extracting a stochastic work-handover relationship model from a stochastic workflow model. As a consequence, the proposed model ought to be useful in performing resource-centric workflow simulations and model-log comparison analyses.