• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.2
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• pp.95-108
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• 1999

The CDMA mobile system consists of several subsystems and each subsystem has many processing elements that handle voice messages and control messages for performing CDMA call processing functions through CDMA Interconnection Network(CIN). For assuring a high throughput and a short delay in the CIN, an efficient medium access control protocol should be provided. In this paper, we propose a new access control protocol of CIN for providing real time communications in CDMA mobile system. Also, we evaluate the delay performance of the proposed access control protocol and compare it with that of the existing access control protocol. Through a set of numerical examples, we show that our proposed protocol provides a better delay performance than the existing protocol.

• Journal of the Korean Society for information Management
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• v.29 no.1
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• pp.279-302
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• 2012

The purpose of this study is to analyze service quality factors that affect user satisfaction of Open Access Korea(OAK) services and to draw strategic assignments for activating open access activities in Korea through a user satisfaction survey. User satisfaction indexes were developed to measure all aspects of the OAK services. The quality index, satisfaction index, and performance index were identified in this survey. According to the survey findings, the levels of social quality and social satisfaction are relatively high, this shows the positive evaluation and expectation of researchers for OAK services. However, relatively low level is identified in the area of service process quality, and many opinions about OA contents shortage in Korea represent the importance of the national level contents development strategy. Sustainable policy support, publishing of open access journals, management of institutional repository, OA governance system, expansion of researchers' participation, construction of global collaboration system are suggested as major implications to promote open access activities in Korea.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.282-304
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• 2014

Each cloud service has numerous owners and tenants, so it is necessary to construct a privacy preserving identity management and access control mechanism for cloud computing. On one hand, cloud service providers (CSP) depend on tenant's identity information to enforce appropriate access control so that cloud resources are only accessed by the authorized tenants who are willing to pay. On the other hand, tenants wish to protect their personalized service access patterns, identity privacy information and accessing newfangled cloud services by on-demand ways within the scope of their permissions. There are many identity authentication and access control schemes to address these challenges to some degree, however, there are still some limitations. In this paper, we propose a new comprehensive approach, called Privacy pReserving Identity and Access Management scheme, referred to as PRIAM, which is able to satisfy all the desirable security requirements in cloud computing. The main contributions of the proposed PRIAM scheme are threefold. First, it leverages blind signature and hash chain to protect tenant's identity privacy and implement secure mutual authentication. Second, it employs the service-level agreements to provide flexible and on-demand access control for both tenants and cloud services. Third, it makes use of the BAN logic to formally verify the correctness of the proposed protocols. As a result, our proposed PRIAM scheme is suitable to cloud computing thanks to its simplicity, correctness, low overhead, and efficiency.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.287-295
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• 2017

Recently, MTC (Machine Type Communication) is known as an important part to support IoT (Internet of Things) applications. MTC provides network connectivities between MTC devices without human intervention. In MTC, a large number of devices try to access over communication resource with a short period of time. Due to the limited communication resource, resource contention becomes severe and it brings about access failures of devices. To solve the problem, it needs to regulate device accesses. In this paper, we present an efficient access management scheme. We measure the number of devices which try to access in a certain time period and predict the change of the number of devices in the next time period. Using the predicted change, we control the number of devices which try to access. To verify our scheme, we conduct experiments in terms of success probability, failure probability, collision probability and access delay.

• The Journal of Society for e-Business Studies
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• v.3 no.1
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• pp.81-94
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• 1998

In Client/Server environments, an employee should be able to access only applications which were assigned to him/her. That makes it difficult to share information among employees. The development of intranet system made it possible to share more information and to access broader information. In this paper, we present a parts management system developed by using Intrabuilder which is an intranet development tool. We intend to suggest a prototype which can guide the development of more delicate and complete parts management systems in the future.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.237-239
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• 2007

In the paper, we analyze the performances of random access channels in multi-service multi-user OFDMA systems. The resource of the random access channels in OFDMA systems is the nubmer of available sub-channels and PN-codes. For given available sub-channels and PN-codes. we analyze the performances of the random access channels of OFDMA systems according to three resource allocation methods (resource full sharing, resource partial sharing, resource partition) in tenus of the access success probability, the blocking probability, the access delay and the throughput of each service class. Further, we find the feasible region of the access probability of each service class in which the allowable minimum access success probability, the allowable maximum blocking probability and the allowable maximum access delay are satisfied. The results also can be utilized to find proper region of the access probabilities of each service class for differentiated quality of service(QoS)s, and for the system operations.

• International journal of advanced smart convergence
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• v.10 no.4
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• pp.52-58
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• 2021

Data access bias can be observed in various types of computing systems. In this paper, we characterize the data access bias in modern mobile computing platforms. In particular, we focus on the access bias of data observed at three different subsystems based on our experiences. First, we show the access bias of file data in mobile platforms. Second, we show the access bias of memory data in mobile platforms. Third, we show the access bias of web data and web servers. We expect that the characterization study in this paper will be helpful in the efficient management of mobile computing systems.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.4
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• pp.101-115
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• 2021

Access re-review is a valuable and important task, but it is burdensome for archivists. Thus, an access re-review automation was proposed to address this. In this situation, the National Archives of Korea actually utilized the access re-review solution in the performance of the "2020 Access Re-Review Project" and compared and analyzed it with human work. The project was, however, not a research project centered on analysis on access re-review solutions, and it has a limited result in terms of experimental use of commercial programs. Nevertheless, in the current situation where there are only macro and superficial discussions on access re-review of intelligent archives, it would be meaningful to apply the access re-review solution to archivists in real businesses and examine the results. This paper seeks to discuss the practicality that can mitigate the task of access re-review through an analysis of use cases of access re-review solutions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.49-52
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• 2011

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.1
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• pp.35-41
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• 2016

Internet of Things (IoT) services are widely used in appliances of daily life and industries. IoT services also provide various conveniences to users and are expected to affect value added of all industries and national competitiveness. However, a variety of security threats are increased in IoT environments and lowers reliability of IoT devices and services that make some obstacles for commercialization. The attacks arising in IoT environments are making industrial and normal life accidents unlike existing information leak and monetary damages, and can expand damage scale of leakage of personal information and privacy more than existing them. To solve these problems, we design a session key based access control scheme for secure communications in IoT environments. The proposed scheme reinforces message security by generating session key between device and access control network system. We analyzed the stability of the proposed access scheme in terms of data forgery and corruption, unauthorized access, information disclosure, privacy violations, and denial of service attacks. And we also evaluated the proposed scheme in terms of permission settings, privacy indemnity, data confidentiality and integrity, authentication, and access control.