• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.143-150
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• 2003

Error concealment plays an important role in combating transmission errors. Methods of error concealment which produce better quality are generally of higher complexity, thus making some of the more sophisticated algorithms is not suitable for real-time applications. In this paper, we develop temporal and spatial error resilient video encoding and data hiding approach to facilitate the error concealment at the decoder. Block interleaving scheme is introduced to isolate erroneous blocks caused by packet losses for spatial area of error resilience. For temporal area of error resilience, data hiding is applied to the transmission of parity bits to protect motion vectors. To do error concealment quickly, a set of edge features extracted from a block is embedded imperceptibly using data hiding into the host media and transmitted to decoder. If some part of the media data is damaged during transmission, the embedded features are used for concealment of lost data at decoder. This method decreases a complexity of error concealment by reducing the estimation process of lost data from neighbor blocks. The proposed data hiding method of parity bits and block features is not influence much to the complexity of standard encoder. Experimental results show that proposed method conceals properly and effectively burst errors occurred on transmission channel like Internet.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.2
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• pp.174-188
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• 2004

In the life environment changed with not only the quality and the price of the products but also the material abundance, it is the most crucial factor for the strategy of product sales to investigate consumer's sensibility and preference degree. In this perspective, it is necessary to design and merchandise the products in cope with each consumer's sensibility and needs as well as its functional aspects. In this paper, we propose the Fashion Design Recommender Agent System (FDRAS-pro) for textile design applying collaborative filtering personalization technique as one of the methods of material development centered on consumer's sensibility and preference. For a collaborative filtering system based on textile, Representative-Attribute Neighborhood is adopted to determine the number or neighbors that will be used for preferences estimation. Pearson's Correlation Coefficient is used to calculate similarity weights among users. We build a database founded on the sensibility adjectives to develop textile designs by extracting the representative sensibility adjectives from users' sensibility and preferences about textile designs. FDRAS-pro recommends textile designs to a customer who has a similar propensity about textile. To investigate the sensibility and emotion according to the effect of design factors, fertile designs were analyzed in terms of 9 design factors, such as, motif source, motif-background ratio, motif variation, motif interpretation, motif arrangement, motif articulation, hue contrast, value contrast, chroma contrast. Finally, we plan to conduct empirical applications to verify the adequacy and the validity of our system.

• Journal of KIISE:Software and Applications
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• v.33 no.6
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• pp.580-587
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• 2006

As PDA, IMT-2000, and e-Book are developed and popular in these days, the number of users who use these products has been increasing. However, available memory size of these machines is still smaller than that of desktop PCs. In these products, TrueType fonts have been increased in demand because the number of users who want to use good quality fonts has increased, and TrueType fonts are of great use in Windows CE products. However, TrueType fonts take a large portion of available device memory, considering the small memory sizes of mobile devices. Therefore, it is required to reduce the size of TrueType fonts. In this paper, two-phase compression techniques are presented for the purpose of reducing the sire of hangul bitmap data embedded in TrueType fonts. In the first step, each character in bitmap is divided into initial consonant, medial vowel, and final consonant, respectively, then the character is recomposed into the composite bitmap. In the second phase, if any two consonants or vowels are determined to be the same, one of them is removed. The TrueType embedded bitmaps in Hangeul Wanseong (pre-composed) and Hangul Johab (pre-combined) are used in compression. By using our compression techniques, the compression rates of embedded bitmap data for TrueType fonts can be reduced around 35% in Wanseong font, and 7% in Johab font. Consequently, the compression rate of total TrueType Wanseong font is about 9.26%.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.11
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• pp.675-690
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• 2003

In this paper, we present the virtual dancing studio for distributed virtual environment. In this system, geographically distributed user shares the virtual dancing hall and interacts with each other. The participating object can be a graphical avatar or a live video stream. It allows the coexistence of graphic objects and real images in the shared virtual space. One of the main technical challenges in developing the distributed virtual environment is to handle excessive network traffic. In an effort to effectively reduce the network traffic, we propose a scheme to adjust the QoS of each object with respect to the distance from the observer in the virtual space. The server maintains the QoS vector for each client's shared space and controls the packet traffic to individual clients based on its QoS vectors. We develop a proto-type virtual dancing environment. Java based development enables the client to be platform independent. The result of experiment shows that the adoption of hierarchical QoS management significantly reduces the overall network traffic.

• Journal of the Korean Society for Nondestructive Testing
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• v.17 no.2
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• pp.108-113
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• 1997

Ultrasonic testing is one of the most widely used method of nondestructive testing for pre-service inspection(PSI) & in-service inspection(ISI) in structures of bridges, power plants, chemical plants & heavy industrial fields. It is very important to estimate safety, life, quality of structures. Also, a lot of research for quantities evaluation & analyses inspection data is proceeding. But traditional portable ultrasonic flaw detector had been following disadvantages. 1) Analog ultrasonic flaw detector decreased credibility of ultrasonic test, because it is impossible for saving data & digital signal processing. 2) Stand-alone digital ultrasonic flaw detector cannot effectively evaluate received signals because of lack of its storage memory. To overcome this shortcoming, we develop the computer based ultrasonic flaw detector for nondestructive testing. It can store the received signal and effectively evaluate the signal, and then enhance the reliability of the testing results.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.718-725
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• 1994

The applicability of near infrared reflectance spectroscopy (NIRS) to determine moisture, protein, fat and amylose content of domestic rice was studied. The standard error of prediction (SEP) of moisture, protein, fat and amylose in polished rice was 0.014, 0.196, 0.098 and 1.427%, and those SEP of brown rice was 0.12, 1.226, 0.153 and 1.923%, respectively. It is concluded that the NIRS method allowed to detect the content of moisture and protein in rice samples with fair precision comparing conventional analysis, but the accuracy for determining amylose and fat was not acceptable.

• Journal of KIISE:Information Networking
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• v.35 no.6
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• pp.538-548
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• 2008

In the Internet Engineering Task Force(IETF), Next Step in Signaling(NSIS) working group, proposed a mechanism to discover the Crossover Node(CRN), when the route is changed by Mobile Node(MN) handover. The CRN is divergence or convergence node on old and new path for reserving resources. Trough the CRN discovery mechanism, it possible to reduce a signaling delay and avoid the redundant reservation on the common path between old and new path. However, the QoS(Quality of Service) can be guaranteed continuously while the MN is performing handover, it is needed to pre-reserve the resource on the new path before completion of the handover. When the nodes on the new path try to make a pre-resource reservation before the handover, it is difficult to pre-reserve the resource with the existing CRN discovery mechanism. Therefore, we proposed a Passive CRN(PCRN) discovery scheme and pre-resource reservation mechanism. The PCRN which means an initial common point between the current reserved and the new paths, where the handover can take place.

• Journal of KIISE:Software and Applications
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• v.31 no.8
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• pp.1043-1053
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• 2004

The performance of a component can significantly influence the overall performance of the system being developed in the component based software development. Existing performance measurement tools for components are often built specific to the component model or middleware. One disadvantage of this approach is that when the system is moved to a new platform during the life-cycle of the system, the measurement tools also need to be adapted. A similar problem is observed when components built for different platforms are integrated with a new integration technology like Web Services. This paper presents a new model for measuring component performances, which is independent of particular component models or middleware. This method presents a interoperability for each performance data by model transformation process from middleware independent performance measuring models to middleware dependent performance measuring models. Our model allows objective performance data to be obtained that can be used to compare performances of components based on different component models or middleware platforms.

• Information and Communications Magazine
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• v.13 no.4
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• pp.56-63
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• 1996

In this paper, the phisical layer of 4.3008 Mcps wideband CDMA which is proposed as the standard of personal communication service system is introduced. It is designed to fit 5 MHz bandwidth by using $28{\times}2^n$ Hadamard code. 13 kbps CELP vocoder is chosen as the main one and 32 kbps ADPCM can be applied. In the reverse link, the burst pilot scheme is proposed and produces the increase of capacity compared with the continuous pilot method. In order to maintain the service quality when the signaling data is increased, the information data and signaling data are time-multiplexed and making use of signaling activity brings the increase of capacity. QPSK data and QPSK spreading, variable frame size, and code pair assignment for high data rate are accomplished and then information data is transmited up to 64 kbps. It is expected that the proposed techiniques here are used in the FPLMTS.

• Analytical Science and Technology
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• v.16 no.5
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• pp.418-425
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• 2003

Inorganic elemental content of bottom ash generated from municipal solid waste incinerator was determined by neutron activation analysis. Bottom ash samples were collected monthly from incinerator located in city D, strained out by the 5 mm sieve, dried by oven and pulverized by agate mortar. The samples were irradiated at NAA #1 irradiation hole in HANARO research reactor of Korea Atomic Energy Research Institute and the irradiated samples were measured by HPGe-gamma-ray spectrometer. From the activity of measured nuclides, 33 elements including As, Cr, Cu, Fe, Mn, Sb and Zn were determined applying activity creation formula and nuclear data. The quality control was conducted by simultaneous analysis with NIST standard reference materials.