• Journal of Information Processing Systems
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• v.10 no.1
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• pp.36-54
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• 2014

Resource sharing is a major advantage of distributed computing. However, a distributed computing system may have some physical or virtual resource that may be accessible by a single process at a time. The mutual exclusion issue is to ensure that no more than one process at a time is allowed to access some shared resource. The article proposes a token-based mutual exclusion algorithm for the clustered mobile ad hoc networks (MANETs). The mechanism that is adapted to handle token passing at the inter-cluster level is different from that at the intra-cluster level. It makes our algorithm message efficient and thus suitable for MANETs. In the interest of efficiency, we implemented a centralized token passing scheme at the intra-cluster level. The centralized schemes are inherently failure prone. Thus, we have presented an intra-cluster token passing scheme that is able to tolerate a failure. In order to enhance reliability, we applied a distributed token circulation scheme at the inter-cluster level. More importantly, the message complexity of the proposed algorithm is independent of N, which is the total number of nodes in the system. Also, under a heavy load, it turns out to be inversely proportional to n, which is the (average) number of nodes per each cluster. We substantiated our claim with the correctness proof, complexity analysis, and simulation results. In the end, we present a simple approach to make our protocol fault tolerant.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2
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• pp.347-354
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• 2000

This paper presents the efficient mechanisms for concurrency control and writing authority control in collaborative writing system are represented by the tree structures which consist of the logical objects and the content objects connected to the terminal objects of trees. For concurrency control, we adopted the approach to extend the multiple-granularity-locking-scheme. This scheme allows us to lock any objects at each level of the hierarchy. We also defined the locking compatibility table by analysing the operations applicable to any objects at each level of the hierarchy. We finally suggest the extended-multiple-granularity-locking mechanism which uses the locking compatibilility table for deciding to lock an object. This scheme gives the benefit to maximize the possibility of concurrent accessing to the shared objects. In addition, we suggest a mechanism for writing authority control which prohibits the Non-Group users from modifying the shared objects based on the concept of Group/Non-Group The proposed mechanism allows us to protect copyright very reasonably.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.794-802
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• 2017

Unmanned Aerial Vehicles (UAVs) have been considered as valuable aerial reconnaissance systems and our army wants capability-enhanced UAVs installed in our territory, hoping that the UAVs will provide enemy information in detail. The enemy information acqcuired by UAVs would be shared by our army's legacy systems. In this article, we made a research on the interoperability between UAVs and Ground Fighting Vehicles (GFVs), laying emphasis on what kinds of tactical information could be exchanged by two different weapon systems. Also, it needs to be addressed that their upper-level commanding systems play a significant role in such operation.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.199-201
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• 2012

디스크나 이더넷과 같은 I/O 장치로부터 발생하는 I/O 트래픽은, 여러 개의 노드를 가진 NUMA 시스템의 공유 LLC에 캐시 오염을 일으켜 캐시 라인이 재사용되는 것을 방해한다. 이러한 태스크는 캐시를 효율적으로 이용할 수 있는 메모리 집중적인 태스크들과 따로 분리하여 다룰 필요가 있다. 본 논문에서는 이러한 캐시 오염을 발생시키는 태스크들을 해당 태스크의 I/O 트래픽을 이용하여 실시간으로 감시하고 분류하는 기법을 제안한다. 또한 대량의 I/O 트래픽을 일으키는 태스크의 특성을 알아본다. 이를 통해, NUMA 시스템 환경에서 각 노드의 공유 LLC를 보다 효율적으로 사용할 수 있는 운영체제 스케줄링 기법을 연구하기 위한 토대를 마련하였다.

• The Journal of Society for e-Business Studies
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• v.3 no.1
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• pp.175-194
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• 1998

The purpose of this study is to examine the current status of Quick Response adoption, and to recognize the implementation problems of QR system in the Korean fashion industry. We reviewed the theoretical background of QR system, analyzed the current status of QR adoption, and identified critical issues to implement the system in our fashion business environment. Previous literatures and information gained from communication service organizations were used for this study The major problems recognized are lack of inter-organizational information network, closed supply channels, non-standardization of QR implementation, and low level of information technology usage including KAN, POS, and EDI. Strong mutual partnership between streams for shared common goals and clear QR mind setting of top management with commitment to information sharing are considered needed for the successful adoption of QR system in domestic fashion industry.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.6
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• pp.171-181
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• 2014

CSV(Creating Shared Value) model was proposed by Porter and Kramer (2011) to address relationship between businesses and society. Namely, it means that CSV deals with business value and social problem solving simultaneously. In this paper, the notion of CSV was applied to the food enterprise, and the cases of CSV with farming area were discovered. Especially, this paper proposed the framework for analyzing CSV activity based on the three-level of CSV suggested by Porter and Kramer (2011) and strategic options for vertical coordination proposed by Peterson et al. (2001). As a result of case analysis applying the proposed framework in this study, three types of CSV activity were discovered: Local food type, downstream support type, and joint corporate establish type. Local food type creates CSV based on momentary purchase or specification contract as strategic options for vertical coordination. Downstream support type creates CSV mainly based on relation-based alliance as a strategic option for vertical coordination. Lastly, joint corporate establish type creates CSV based on equity-based alliance as a strategic option for vertical coordination. This paper contributed to the CSV literatures for discovering cases of CSV with farming area and categorizing discovered cases applying proposed framework.

• Educational Technology International
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• v.9 no.1
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• pp.49-77
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• 2008

As clearly suggested in the case of Wikipedia, collective intelligence is predicted to develop into the most important platform of knowledge and information in the future society. But it just remains at the level of activities for group projects in the present frame of education and so it doesn't lead to creating collective intelligence. This study looks into an 'information repository model of collective intelligence' that makes it possible to deliver an education process a priori of Shared Knowledge Reservoir to "Junior Digital Nomad", who is definitely and will be in existence, and that further enables them to be active there in reality. Based on this storage model, it suggests a practicable web system model; Junior Maphistory e-encyclopedia, which is appropriately consistent with the features of Web 2.0 and can grow into a general historical and geographical information service.

• Journal of Advanced Navigation Technology
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• v.23 no.2
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• pp.207-213
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• 2019

Recently, the importance for internet of things (IoT) security has increased enormously and hardware-based compact chips are needed in IoT communication industries. In this paper, we propose low-complexity crypto-processor that unifies advanced encryption standard (AES), academy, research, institute, agency (ARIA), and CLEFIA protocols into one combined design. In the proposed crypto-processor, encryption and decryption processes are shared, and 128-bit round key generation process is combined. Moreover, the shared design has been minimized to be adapted in generic IoT devices and systems including lightweight IoT devices. The proposed crypto-processor was implemented in Verilog hardware description language (HDL) and synthesized to gate level circuit in 65nm CMOS process, which results in 11,080 gate counts. This demonstrates roughly 42% better than the aggregates of three algorithm implementations in the aspect of gate counts.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.29 no.1
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• pp.47-60
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• 2021

Just culture is an important factors in safety culture, and is related to the degree to which potential risk information is shared. Since the importance of the level of just culture has been highlighted in the aspect that it is related to the prevention of various safety accidents, research on just culture was required. In previous studies, there are attempts to develop a scale to measure the level of just culture and to reveal the degree of predicting the experience of accidents or errors and the actual reporting experience. However, It was not possible to clarify the factors that facilitate and inhibit the level of just culture for the formation of just culture. This study was conducted to help improve the level of the organization's just culture by specifically identifying factors that facilitate and inhibit the impact on the level of the just culture. As a result, it was possible to find the facilitating and inhibiting factors affecting the 6 factors of just culture.

• Journal of KIISE:Software and Applications
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• v.26 no.10
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• pp.1178-1178
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• 1999

A spatial join has the property that its execution time exponentially increases in proportion to the number of spatial objects. Recently, there have been many attempts for improving the performance of the spatial join by using parallel processing schemes, In the case of executing parallel spatial join using the parallel machine with shared disk architecture, the disk bottleneck of parallel processing of spatial join worsens in comparison with sequential spatial join. This paper presents the algorithms of task creation and assignment to reduce the disk bottleneck caused by accessing the shared disk at the same time, and to minimize message passing between processors, This paper proposes object caching which is a higher level of abstraction than page caching, and uses it to do creation and assignment of tasks according to temporal and spatial localities for minimizing disk access time. The object caching shows the performance improvement of 50%. The task creation and assignment using localities gives the gain of 30% and 20%. Overall performance evaluation of the proposed algorithms shows 7.2 times speed up than those of sequential execution of spatial joins.