• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10C
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• pp.758-763
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• 2008

We introduce a noise-predictive turbo equalization using noise filter in perpendicular magnetic recording(PMR) channel. The noise filter mitigates the colored noise in high-density PMR channel. In this paper, the channel detectors used are SOVA (Soft Output Viterbi Algorithm) and BCJR algorithm which proposed by Bahl et al., and the outer decoder used is LDPC (Low Density Parity Check) code that is implemented by sum-product algorithm. Two kinds of LDPC codes are experimented. One is the 0.5Kbyte (4336,4096) LDPC code with the code rate of 0.94, and the other is 1Kbyte (8432,8192) LDPC code with the code rate of 0.97.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.4B
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• pp.427-436
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• 2001

RS product codes are widely used in digital storage systems. There are lots of decoding strategies for product code for short-length RS codes. Unfortunately many of them cannot be applied to long-length RS product codes because of the complexity of decoder. This paper proposes new decoding strategies which can be used in long length RS product codes.

• Journal of Intelligence and Information Systems
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• v.10 no.2
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• pp.1-13
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• 2004

This paper presents a method for the multilingual product retrieval agent through XML and the semantic networks in e-commerce. Retrieval for products is an important process, since it represents interfaces of the customer contact to the e-commerce. Keyword-based retrieval is efficient as long as the product information is structured and organized. But when the product information is expressed across many online shopping malls, especially when it is expressed in different languages with cultural backgrounds, buyers' product retrieval needs language translation with ambiguities resolved in a specific context. This paper presents a RDF modeling case that resolves semantic problems in the representation of product information and across the boundaries of language domains. With adoption of UNSPSC code system, this paper designs and implements an architecture for the multilingual product retrieval agents. The architecture is based on the central repository model of product catalog management with distributed updating processes. It also includes the perspectives of buyers and suppliers. And the consistency and version management of product information are controlled by UNSPSC code system. The multilingual product names are resolved by semantic networks, thesaurus and ontology dictionary for product names.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.866-872
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• 2000

Superplastic forming processes by characteristic of low flow stress and high elongation have advantages to reducing on production cost and weight because of the product of complex form could be made in one part. However superplastically termed part has a characteristic of non-uniform thickness distribution along forming direction. Especially. since the thickness distribution affects on mechanical properties of product. the uniform thickness is very important. There are two solution procedure of implicit and explicit procedure to analyze the superplastic forming. In this study to analyze the thickness distribution two kinds of commercial programs of DEFORM and PAM-STAMP which implicit and explicit code are used respectly. The results from the two Programs were compared with eath other As a result implicit code were more suitable than explicit code for superplastic forming analysis.

• Nuclear Engineering and Technology
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• v.31 no.1
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• pp.88-103
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• 1999

The purposes of this study are to understand the severe accident phenomena, to establish the simulation method for the experimental test, and to assess the current models in MELCOR for future improvement. This paper presents the results of the PHEBUS FPT1 post test analysis using MELCOR computer code, version 1.8.4. The entire PHEBUS facility has been modeled; the core, the primary circuit including the steam generator, and the containment vessel. Both the thermal hydraulic and the fission product behavior have been investigated. The code simulation results of the thermal hydraulic behavior show good agreement with the experimental data, The fission product release and transport are calculated using the CORSOR models in MELCOR code and the results will be compared with the experiment when the experimental data are available.

• Journal of the Korea Society of Computer and Information
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• v.13 no.4
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• pp.1-9
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• 2008

Most consumer electronics companies hold numerous line-ups to cope with divergent customer's needs. To cope with current situation, most products are derived from the 'base product' which is developed for brand new features with respect to the change requests. That is called derivation. After 'base code' is developed for newly introduced products, some modification will occur corresponding to the derivative product models. So, quality attributes of 'base code' affects quality and productivity of 'derived code'. But in the middle of continuous modification to 'base code', violation of architectural design decision and unauthorized or maybe unsophisticated change to source code willing to happen and thus it cause critical problem. Those code has 'aging symptom' both architectural and code level in nature. In this paper, we introduced reengineering framework which guide the procedure and tactics to find and fix 'aging symptom' for improvement on quality attribute of 'base code'.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.119-126
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• 2016

Software maintenance becomes extremely difficult, especially caused by multiple versions in project-based or customer-oriented software development methodology. For reducing the maintenance cost, reengineering to software product line can be a solution to the software which either is a family of products nevertheless little different functionalities or are customized for each different customer's requirement. At an initial stage of the reengineering, the most important activity in software product line is feature extraction with respect to commonality and variability from the existing system due to verifying functional coverage. Several researchers have studied to extract features. They considered only a single version in a single product. However, this is an obstacle to classify the commonality and variability of features. Therefore, we propose a method for systematically extracting features from source code and its change history considering several versions of the existing system. It enables us to represent functionalities reflecting developer's intention, and to clarify the rationale of variation.

• Journal of the Korea Safety Management & Science
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• v.10 no.4
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• pp.189-198
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• 2008

At present, companies write daily work record or use bar-code in order to collect distribution flow data in real time. However, it needs additional works to check the record or read the bar-code with a scanner. In this case, human error could decrease accuracy of data and it would cause problems in reliability. To solve this problem, RFID (Radio Frequency Identification) is introduced in many automatic recognition sector recently. RFID is a technology that identification data is inserted into micro-mini IC chip and recognize, trace, and manage object, animal, or person using wireless frequency. This is being emerged as the core technology in future ubiquitous environment. This study is intended to suggest RFID application method in franchise business. Traceability and visibility of individual product are supplied based on EPCglobal network. It includes DW system which supplies various assessment data about product in supply chain, financial transaction system which is based on product transaction and position information, and RFID middleware which refines and divides product data from RFID tag. With the suggested application methods, individual product's profile data are supplied in real time and it would boost reliability to customer and make effective cooperation with existing operation systems (SCM, CRM, and e-Business) possible.

• Journal of Internet Computing and Services
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• v.5 no.4
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• pp.125-134
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• 2004

Recently a lot of researches on the component-based software product lines and on applying generative programming into software product lines are being performed actively. This paper proposes an automatic component reconfiguration tool that could be applied in constructing the component-based software product lines. Our tool accepts the reuser's requirement via a feature model which is the main result of the domain engineering, and makes the feature configuration from this requirement. Then it generates the source code of the reconfigured component according to this feature configuration. To accomplish this process, the component family in our tool should have the architecture of GenVoca that is one of the most influential generative programming approaches. In addition, XSLT scripts provide the code templates for implementation elements which are the ingredients of the target component. Taking the ‘Bank Account' component family as our example, we showed that our component reconfiguration tool produced automatically the component source code that the reuser wants to create. The result of this paper would be applied extensively for creasing the productivity of building the software product lines.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.1
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• pp.108-114
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• 1988

We have developed a program that minimizes the chip area with effective code assignment of microinstructions when the control part of VLSI system is implemented in the PLA. While conventional algorithms are composed of one pass, the algorithm proposed in this paper is composed of two passes and it consists of three principal procedures: a procedure for the determination of the code assignment order, a procedure for the code assignment and a procedure for the reduction of the code length. especially, we have proposed a new method of folding back for the reduction of the code length. We have obtained the result of 4 bit code length and 9 product terms when 11 micro-instructions and 6 microoperations were given as a inputs. Therefore, we have certified that it could be used efficiently for the control part of the processors.