• Korean Journal of Cognitive Science
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• v.17 no.3
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• pp.231-253
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• 2006

The interaction effects of the cognitive style and the presentation order of learning material was explored in the study. Visualizers performed better when the graphic information was presented prior to the verbal information, whereas verbalizers did better when the verbal information was presented prior to the graphic information. The results of the present research have practical implication of personalized multimedia design based on the learner's cognitive style. The results also have suggested that the cognitive load of a multimedia material can be varied depending on the compatibility of the cognitive style and the material.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8A
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• pp.753-762
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• 2002

Blind equalization of transmission channel is important in communication areas and signal processing applications because it does not need training sequences, nor dose it require a priori channel information. In this paper, an adaptive blind MMSE channel equalization technique based on second-order statistics in investigated. We present an adaptive blind MMSE channel equalization using multichannel linear prediction error method for estimating cross-correlation vector. They can be implemented as RLS or LMS algorithms to recursively update the cross-correlation vector. Once cross-correlation vector is available, it can be used for MMSE channel equalization. Unlike many known subspace methods, our proposed algorithms do not require channel order estimation. Therefore, our algorithms are robust to channel order mismatch. Performance of our algorithms and comparisons with existing algorithms are shown for real measured digital microwave channel.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.287-289
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• 2013

Fast Handover for Proxy Mobile IPv6 (FPMIPv6), a protocol described in RFC 5949, is used to reduce handover latency and minimize packet loss problem occuring in the Proxy Mobile IPv6 (PMIPv6) protocol. However, during the study of implementing FPMIPv6, we found the Out-of-Order Packet (OoOP) problem that occurs in the experiment of FPMIPv6. Since the OoOP is an issue that affects significantly to QoS of the network, in this paper, we analyze the OoOP problem by using network model. The analysis conducts the cause of occurring OoOP problem due to there exist two paths for data transmitted from Correspondent Node (CN) to MN in FPMIPv6.

• The Journal of Information Systems
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• v.18 no.1
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• pp.77-95
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• 2009

In customer-oriented make-to-order manufacturing environments, the works of BOM changes due to the changes of product specification and engineering are closely connected with almost all departments such as sales, engineering, production, procurement, cost, after service, etc within an enterprise. So, the contents of BOM changes must be instantly reflected on the related works among the departments. To effectively process these complex works of BOM changes, types of changes on product specification and engineering and types of BOM changes linked with those must be systematically defined, classified and managed by information systems. Thus, it is necessary to introduce solutions such as BPM and SOA in order to efficiently deal with complex business processes like BOM change management. This paper proposes a methodology of constructing information systems based on BPM and SOA. The proposed methodology defines the relationship between processes of BPM for definition, execution, monitoring, etc of business processes and services of SOA for connection among information systems within an enterprise, and presents a scheme of practically applying BPM and SOA solutions to actual business works. To show an utilization of the proposed methodology, the prototype system for product BOM management is implemented in order to efficiently deal with the works of BOM changes due to the changes of product specification and engineering.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.6
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• pp.350-359
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• 2014

With the rapid growth of Internet, the importance of application traffic analysis is increasing for efficient network management. The statistical information in traffic flows can be efficiently utilized for application traffic identification. However, the packet out-of-order and retransmission occurred at the traffic collection point reduces the performance of the statistics-based traffic analysis. In this paper, we propose a novel method to detect and resolve the packet out-of-order and retransmission problem in order to improve completeness and accuracy of the traffic identification. To prove the feasibility of the proposed method, we applied our method to a real traffic analysis system using statistical flow information, and compared the performance of the system with the selected 9 popular applications. The experiment showed maximum 4% of completeness growth in traffic bytes, which shows that the proposed method contributes to the analysis of heavy flow.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.879-892
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• 2021

In a make-to-order manufacturing environment, the manufacturer's quotation information is important information used as basic information for bidding, receiving orders, and producing products in response to various customer demands. This quotation information is changed according to various factors such as customer demands, changes in product production environment, changes in drawing information of technical partners, and technological improvement of products. Due to this change, various changes occur in the quotation information that the manufacturer is preparing to reflect the customer's requirements. The change of quotation information according to these various change factors puts a lot of burden on the quotation management work from the standpoint of a make-to-order manufacturing company. In particular, the change of quotation information due to the change factors of quotation is inevitable and frequently occurs due to the requirements of the customer in the customer-oriented make-to-order production environment. In this paper, we propose a quotation change process based on the quotation creation process and propose a consistent and efficient quotation change processing method. To this end, the factors causing the change of quotation were defined, and the types of changes for each factor were defined. And it shows the procedure of applying the quotation change process to the quotation management system through the cases of each cause of the quotation change. In addition, in order to show the usefulness of the quotation change factors, the type of quotation change, the quotation change process, and the quotation system management, the proposed quotation change process and function was applied in the integrated quotation management system for the ship engine division of a typical make-to-order manufacturing company 'H'. As a result, it was confirmed that the proposed quotation change process and management system according to the quotation change factors were efficiently performed.

• Journal of the Korean Society of Costume
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• v.38
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• pp.289-304
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• 1998

In Korean clothing industry, most of the manufactures produce garments by subcon-tractors partially or entirely. It is very often that the design part is remote from production part and there is miscommunication between these two parts resulting dissatisfaction to both. Therefore it is very important to communicate the manufacturing information clearly and quickly to produce garments exactly the design part intended. Also to automate the clothing out how to produce and use the information objectively and efficiently. As a first step of moving to automation, the purpose of the research is to find out how manufacturing information and data are communicated in clothing manufacturing at present. In order to follow the information flow of a cer-tain manufacturer, the case study method was used. The case study samples were 12 clothing firms of 13 brands. The results and suggestions are as follows :- 1. A manufacturing information is communicated through paper documents such as“Production Order”, sample and patterns. At present, a production order sheet is the most efficient communication media, which comprises most of the information being communicated. 2. A manufacturing information comprises control information on the product, design in-formation, pattern information, cutting information, material information, sewing information, production schedule information, quality control information, costing information and information about the subcontractors. 3. A manufacturing is not quite objective except pattern information and cutting information which is presented by CAD systems. The communication of design information and sewing information should be somehow more objective. 4. There is not much information from a subcontractor. Considering that a subcontractor is the other partener of the communication, more information from the subcontractor is required for both benefit. 5. A designer produce most of the manufacturing information, but the information is communicated through a production manager to the subcontractor. The difference between the information maker and information communicator can cause any miscommunication. In future automated manufacturing, it will be possible for the designer to communicate to the manufacturer directly from the early stage of designing.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1007-1011
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• 2003

In this paper, a design of I-PDA controller by CDM to control a flow process whose structure is first order lag plus a dead time is introduced. The factor of dead time of the process is approximated by second order Pade approximation in order to get a third order system. The simulations show that both of the transient and steady state specifications can be fulfilled. However, the transient response of the I-PDA control system still has long rise time. Then, a feedforward controller (FFC) with two adjustable parameters and one derivative time is introduced into I-PDA control system for improving the speed of the system response. It is shown, from the simulation results, that the performance of the I-PDA control system with suitable FFC has shorter rise time and no overshoot, while settling time remains almost the same. The performance comparison of the proposed control system with the PI control system with and without FFC is also made.

• Journal of Computing Science and Engineering
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• v.8 no.2
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• pp.94-106
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• 2014

Schema matching is widely used in many applications, such as data integration, ontology merging, data warehouse and dataspaces. In this paper, we propose a novel matching technique that is based on the order of attributes appearing in the schema structure of query results. The appearance order embodies the extent of the importance of an attribute for the user examining the query results. The core idea of our approach is to collect statistics about the appearance order of attributes from the query logs, to find correspondences between attributes in the schemas to be matched. As a first step, we employ a matrix to structure the statistics around the appearance order of attributes. Then, two scoring functions are considered to measure the similarity of the collected statistics. Finally, a traditional algorithm is employed to find the mapping with the highest score. Furthermore, our approach can be seen as a complementary member to the family of the existing matchers, and can also be combined with them to obtain more accurate results. We validate our approach with an experimental study, the results of which demonstrate that our approach is effective, and has good performance.

• Journal of Information Processing Systems
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• v.14 no.5
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• pp.1087-1101
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• 2018

As cloud computing has become a widespread technology, malicious attackers can obtain the private information of users that has leaked from the service provider in the outsourced databases. To resolve the problem, it is necessary to encrypt the database prior to outsourcing it to the service provider. However, the most existing data encryption schemes cannot process a query without decrypting the encrypted databases. Moreover, because the amount of the data is large, it takes too much time to decrypt all the data. For this, Programmable Order-Preserving Secure Index Scheme (POPIS) was proposed to hide the original data while performing query processing without decryption. However, POPIS is weak to both order matching attacks and data count attacks. To overcome the limitations, we propose a group order-preserving data encryption scheme (GOPES) that can support efficient query processing over the encrypted data. Since GOPES can preserve the order of each data group by generating the signatures of the encrypted data, it can provide a high degree of data privacy protection. Finally, it is shown that GOPES is better than the existing POPIS, with respect to both order matching attacks and data count attacks.