• Journal of the Korean Operations Research and Management Science Society
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• v.32 no.1
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• pp.125-136
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• 2007

The study on query relaxation which provides approximate answers has received attention. In recent years, some arguments have been made that semantic relationships are useful to present the relationships among data values and calculating the semantic distance between two data values can be used as a quantitative measure to express relative distance. The aim of this article is a hierarchical metricized knowledge abstraction (HiMKA) with an emphasis on combining data abstraction hierarchy and distance measure among data values. We propose the operations and the query relaxation algorithm appropriate to the HiMKA. With various experiments and comparison with other method, we show that the HiMKA is very useful for the quantified approximate query answering and our result is to offer a new methodological framework for query relaxation.

• Journal of the Korean Society of Systems Engineering
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• v.3 no.2
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• pp.39-48
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• 2007

In this study, an overall product design process will be presented by using the Analytic Hierarchy Process(AHP) and robust design. From the conceptual design stage, the logical methods are used to select the appropriate concepts satisfying the customer requirements and the other conditions. The next phase is the embodiment design phase in which the deterministic and robust design approach are used to obtain the improvement in product design. Typically, this approach is applied for developing the simple bookshelf design. The results show the efficient approach which can be supported to develop the new product.

• ETRI Journal
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• v.34 no.1
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• pp.142-145
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• 2012

The main challenge at present in constructing hierarchical identity-based encryption (HIBE) is to solve the trade-off between private-key size and ciphertext size. At least one private-key size or ciphertext size in the existing schemes must rely on the hierarchy depth. In this letter, a new hierarchical computing technique is introduced to HIBE. Unlike others, the proposed scheme, which consists of only two group elements, achieves constant-size private keys. In addition, the ciphertext consists of just three group elements, regardless of the hierarchy depth. To the best of our knowledge, it is the first efficient scheme where both ciphertexts and private keys achieve O(1)-size, which is the best trade-off between private-key size and ciphertext size at present. We also give the security proof in the selective-identity model.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.6
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• pp.391-397
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• 2015

Nonvolatile memories in memory hierarchy have been investigated to reduce its energy consumption because nonvolatile memories consume zero leakage power in memory cells. One of the difficulties is, however, that the endurance of most nonvolatile memory technologies is much shorter than the conventional SRAM and DRAM technology. This has limited its usage to only the low levels of a memory hierarchy, e.g., disks, that is far from the CPU. In this paper, we study the use of a new type of nonvolatile memories - the Phase Change Memory (PCM) with a DRAM buffer system as the main memory. Our design reduced the total energy of a DRAM main memory of the same capacity by 80%. These results indicate that it is feasible to use PCM technology in place of DRAM in the main memory for better energy efficiency.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.557-562
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• 2009

Weapon system currently considers the research about effect analysis including cost effectiveness methodology for a budget management and an achievement of the military strategy goal. So that, this study considers the theoretical background, strength and weakness of several Multi-Criteria Decision Making, and an effect analysis of weapon system. And AHP(Analytic Hierarchy Process) is selected for the best effect analysis methodology of weapon system. Therefore, we applied AHP to the case study of the new generation Multiple Launcher Rocket System, performing the analysis of cost effectiveness methodology. Using AHP and cost effectiveness methodology, we propose the actual and proper decision making result.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.699-700
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• 2013

This paper proposes a new visualization method based on cloud technique which uses internal relationship of user correlation and external relation of social network to visualize user relationship hierarchy. The proposed method use hadoop and hive for distribution storing and parallel processing which the result of calculation visualizes hierarchy graph using D3.

• Journal of Distribution Science
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• v.18 no.7
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• pp.63-72
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• 2020

Purpose: This study examines the market segmentation and strategy of PT INKA, a rolling stock manufacturer in Indonesia. Research design, data and methodology: The study used the MCDM (Multiple Criteria Decision Making) method specifically the AHP (Analytical Hierarchy Process). The AHP method was applied to identify the target market. This method or approach considers the market attractiveness and competitive strength criteria with quantified parameters. Results: a) Australia, Kenya, Tanzania, New Zealand, and India emerge as the top five target markets; b) There is justification for rolling stock manufacturers to allocate their resources in winning the market share. Conclusion: The main challenge confronting the rolling stock manufacturer is limited resources to acquire a particular market share despite abundant opportunities in this sector. Despite the mastery of technology and long experience in the industry, selecting a target market with multiple criteria could be difficult for an emerging rolling stock manufacturer in South East Asia.

• ETRI Journal
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• v.34 no.2
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• pp.159-167
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• 2012

In this paper, a new distributed resource allocation algorithm is proposed to alleviate the cross-tier interference for orthogonal frequency division multiplexing access macrocell and femtocell overlay. Specifically, the resource allocation problem is modeled as a non-cooperative game. Based on game theory, we propose an iterative algorithm between subchannel and power allocation called distributed resource allocation which requires no coordination among the two-hierarchy networks. Finally, a macrocell link quality protection process is proposed to guarantee the macrocell UE's quality of service to avoid severe cross-tier interference from femtocells. Simulation results show that the proposed algorithm can achieve remarkable performance gains as compared to the pure waterfilling algorithm.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.3
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• pp.47-54
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• 1996

In this paper we propose a new timing recovery method by means of utilizing service data filling rate instead of timing information of transmitter. A proposed algorithm controls the phase locked loop in the opposite direction ot data filling rate of FIFO in receiver, and it is based on the fact that average of cell jitters is zero. The proposed method is simple compared with timing information method of transmitter. It can be utilized for timing recovery in synchronous digital hierarchy as well as in plesiochronous digial hierarchy without common reference clocks in end-to-end erminals. We implement the interactive video communication system and test the proposed algorithm. As a result, we hav econfirmed that it yields good perfomrnces in terms of jitters characteristics and hardware complexity.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.2 s.257
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• pp.260-268
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• 2007

Demand for the use of 3D CAD DMU systems over the Internet environment has been increased. However, transmission of commercial 3D kernels has delayed the communication effectiveness due to the kernel size. Light weight CAD geometric kernel design methodology is required for rapid transmission in the distributed environment. In this paper, an assembly data structure suitable for the top-down and bottom-up assembly models has been constructed. Part features are stored without a hierarchy so that they are created and saved in no particular order. In particular, this paper proposes a new assembly representation model, called multi-level assembly representation (MAR), for the PDM based assembly DMU system. Since the geometric kernel retains assembly hierarchy and topological information, it is applied to the web-viewer for the PDM based DMU system. Effectiveness of the proposed geometric kernel is confirmed through various case studies.