• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.4
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• pp.487-492
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• 2011

This paper proposes a retransmission persistence control scheme for automatic retransmit request (ARQ) protocol to improve the reliability of a wireless link. Most existing ARQ protocols adopt a fixed retransmission persistence. If the ARQ protocol sets the retransmission persistence too low, there is a limitation in providing transmission reliability. On the other hand, if the ARQ protocol sets the retransmission persistence too high, it increases transmission delay and jitter. In order to figure out the problem, the proposed scheme considers the number of frames in the buffer in controlling the retransmission persistence; it improves the throughput of ARQ protocol by increasing the retransmission persistence when the number of frames is small and decreasing otherwise. Simulation results show that the proposed scheme decreases the transmission delay and jitter significantly comparing to the existing schemes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8A
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• pp.610-617
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• 2009

This paper proposes a cross-layer design combining adaptive modulation and coding (AMC) with truncated hybrid automatic repeat request (HARQ) for wireless multicast transmission, in order to increase the spectral efficiency while meeting the target quality-of-service (QoS). In the design, we provide the selection criterion of AMC so as to satisfy the target packet error rate (PER) of all users when the multicast data is received through the common channel and the number of retransmission is limited by the delay constraint of the service. The analytically derived results show that the cross-layer design using HARQ provides a better spectral efficiency than the AMC without HARQ by allowing retransmission and code combining. It is also observed that the design for multicast outperforms that for unicast in the mid to high signal-to-noise ratio region.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.3
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• pp.101-110
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• 2008

We believe distinguishable product development to be competitive against foreign products, and realize the need to expand domestic business worldwide. In order to be competitive, we should produce fashion items that meets global taste, and at the same time contain exclusive Korean culture and emotional beauty. This article examines and creates unique textile design with the touch of Korean art. Desigus have been proceeded under the following three themes: 'Strong Ego,' 'Gorgeous Days' and 'Song Eternal Seeking Love' using Primavision Computer-aided Design ("CAD"). We have put our interestes in Korean traditional paintings called Hangukhwa. Suitable design motives had been selected and modified from the four gracious plants (bamboos, peonies etc.), and paintings of birds and flowers. Primavision, a CAD software, had been used to manipulate those desigus, and to add instant changes in color, scale, and layout. We had modified Korean traditional motives to make modem image, and had arranged layouts which can be suitable for half-drop repeat and square repeat. The use of color is essential in pattern design. Thus, we explored coloring ways for each design to meet the trends, and the final mapping had been conducted in western style of dresses. We have tried to mix Korean image of textile designs with Western clothing style, expressing hybrid in the mapping process. With global movements, we need to develop products with Korean traditional exotic taste to attract foreign consumers. Therefore, we selected symbolic motives from Korean paintings to express deep spiritual significance. We developed textile design and processed mapping on selected western designer's dress, employing current trend colors and making crossover coordination. We realized Korean painting would be an excellent source for exclusive fabric design, and tried to create a modernized design which maintains Korean ethnical identities.

• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.111-121
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• 2010

In order to investigate the preliminary repeat oral dose toxicity and to determine the highest dosage for further 4-week repeated dose toxicity test, Low Molecular Weight Fucoidan (LMF) has been showed various pharmacological effects, was orally administered to female and male rats, once a day for 14 days at dose levels of 2,000, 1,000, 500 and 0 (vehicle control) mg/kg (body weights) in a volume of 10 ml/kg. The mortality and changes on the body weights, clinical signs, hematology, serum biochemistry and gross observations were monitored with organ weight and histopathology of principle organs. As the results of 14-day repeated oral treatment of LMF, no LMF treatment related mortalities were detected up to 2,000 mg/kg in both male and female rats, respectively. In addition, no noticeable changes on the body weight and clinical signs were detected except for significant decreases on the body weights and gains restricted to male 2,000 mg/kg treated groups as compared with male vehicle control. No meaningful changes on the organ weights, hematological, serum biochemistrical, gross and histopathological findings were observed. Therefore the highest dosage in the 4-week repeated dose toxicity test is suggested as 2,000 mg/kg in both female and male rats, respectively.

• Journal of Life Science
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• v.16 no.5
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• pp.740-745
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• 2006

Inter simple sequence repeat (ISSR) markers were performed in order to analyse the phylogenetic relationships of four taxa of Castor-aralia (Kalopanax pictus): K. pictus, K. pictus var. magnificus, K. pictus var. maximowiczii, and thornless K. pictus. The 11 primers were produced 64 reproducible ISSR bands. Analysis of ISSR from individual plants of Korean K. pictus resulted in 41 polymorphic bands with 64.1%. When species were grouped by four taxa, within group diversity was 0.115 $(H_S)$, while among group diversity was 0.467 $(G_{ST})$ on a per locus basis. The estimated gene flow (Nm) for K. pictus var. maximowiczii and K. pictus var. magnificus were very higher than K. pictus. It is suggested that the isolation of geographical distance and reproductive isolation among K. pictus populations may have played roles in shaping the population structure of this species. In phenetic tree, ISSR markers are very effective in classifying natural populations as well as taxon levels of genus Kalopanax in Korea.

• Molecules and Cells
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• v.19 no.1
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• pp.104-113
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• 2005

Large inversions are well characterized in the chloroplast genomes of land plants. In contrast, reports of small inversions are rare and involve limited plant groups. In this study, we report the widespread occurrence of small inversions ranging from 5 to 50 bp in fully and partially sequenced chloroplast genomes of both monocots and dicots. We found that small inversions were much more common than large inversions. The small inversions were scattered over the chloroplast genome including the IR, SSC, and LSC regions. Several small inversions were uncovered in chloroplast genomes even though they shared the same overall gene order. The majority of these small inversions were located within 100 bp downstream of the 3' ends of genes. All had inverted repeat sequences, ranging from 11 to 24 bp, at their ends. Such small inversions form stem-loop hairpin structures that usually have the function of stabilizing the corresponding mRNA molecules. Intra-molecular recombination between the inverted sequences in the stem-forming regions are responsible for generating flip-flop orientations of the loops. The presence of two different orientations of the stem-loop in the trnL-F noncoding region of a single species of Jasminum elegans suggests that a short inversion can be generated within a short period of time. Small inversions of non-coding sequences may influence sequence alignment and character interpretation in phylogeny reconstructions, as shown in nine species of Jasminum. Many small inversions may have been generated by parallel or back mutation events during chloroplast genome evolution. Our data indicate that caution is needed when using chloroplast non-coding sequences for phylogenetic analysis.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.157-163
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• 2016

With the rapid expansion of smart-phone based brand app and its marketing implementations, the marketers stake much resources in the success of brand apps so that they are able to reinforce the user satisfaction and intention for repeat use. The purpose of this paper is to understand the characteristics underlying the brand applications and to analyze the usage and attitudes of the users. Self-administered survey on the research variables for respondents of 20-49 age group was conducted and the results as follow. The results are as follows the consumers are more satisfied with its usefulness, entertainment, and design attributes of the brand app. They tend to keep using a brand app that contains useful contents and great entertainment elements. Marketers thus need to reflect those elements when developing and distributing a brand app in order to meet the needs of their customers. The study results would help marketing firms find new competitive edges by providing basic insight for new competition strategies for brand app development.

• The Korean Journal of Pain
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• v.4 no.2
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• pp.111-121
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• 1991

It has been well known that the splanchnic nerve block is effective for patients who suffer from intractable upper abdominal pain. However, it is unclear whether the effect of the splanchnic nerve block depends on varied alcoholic concentration. In this study, an attempt was made to use absolute ethanol on patients who recieved a splanchnic nerve block at Severance Hospital during the period from September l990 to April l991. The results are as follows; 1) Among the 33 patients, including 22 males and 1l females, the fifties and sixties were the major age groups. 2) Stomach cancer was the most common underlying disease(13 cases), with pancreatic can- cer next(9 cases). 3) The main locations of pain were the upper abdomen, epigastrium, and entire abdomen in decreasing order. 4) There were 17 cases who had had chemotherapy, and 1l cases of whom had had surgery before the splanchnic nerve block. 5) The volume of alcohol used was 12 ml bilaterally. 6) Among the 33 patients, 15.2% required a second block within two weeks of the first block. One case required a third block. 7) The most common complications of splanchnic nerve block were hypotension(33.3%), occasional transient sharp burning pain, flushing of face, pain on injection site, nausea, vomiting, dyspnea, chest discomfort and diarrhea. 8) The supplemental block most commonly used was a continuous epidural block. It was used both as a diagnostic block and to afford relief from pain before the splanchnic nerve block was done. 9) The interval between the receiving the absolute ethanol block and discharge was within 2 weeks in l5 cases. But, in the patients with poor general health, the interval between the splanchnic nerve block and discharge prolonged. The above results suggest that bilateral splanchnic nerve block done with absolute ethanol after an effective test block with 1% lidocaine under C-arm fluroscopic control is satisfactory and reliable. Still, 26.6% of the patients received a repeat block within 2 weeks. Insufficient spread of ethanol due to its small volume seems to be a major factor in the repeat block. Minimizing the incidence of repeat block remains a problem to be solved.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.121-128
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• 2012

High resolution intertidal DEM is a basic material for science research like sedimentation/erosion by ocean current, and is invaluable in a monitoring of environmental changes and practical management of coastal wetland. Since the intertidal zone changes rapidly by the inflow of fluvial debris and tide condition, remote sensing is an effective tool for observing large areas in short time. Although radar interferometry is one of the well-known techniques for generating high resolution DEM, conventional repeat-pass interferometry has difficulty on acquiring enough coherence over tidal flat due to the limited exposure time and the rapid changes in surface condition. In order to overcome these constraints, we tested the feasibility of radar interferometry using Cosmo-SkyMed tandem-like one-day data and ERS-ENVISAT cross tandem data with very short revisit period compared to the conventional repeat pass data. Small temporal baseline combined with long perpendicular baseline allowed high coherence over most of the exposed tidal flat surface in both observations. However the interferometric phases acquired from Cosmo-SkyMed data suffer from atmospheric delay and changes in soil moisture contents. The ERS-ENVISAT pair, on the other hand, provides nice phase which agree well with the real topography, because the atmospheric effect in 30-minute gap is almost same to both images so that they are cancelled out in the interferometric process. Thus, the cross interferometry with very small temporal baseline and large perpendicular baseline is one of the most reliable solutions for the intertidal DEM construction which requires very accurate mapping of the elevation.

• The Journal of Korean Society for Radiation Therapy
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• v.33
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• pp.47-54
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• 2021

Purpose : In order to evaluate the usefulness of clinical application of the Pause & Resume methods by comparing and analyzing the data stability and dose reduction effect when repeat scan assuming irregular breathing and using the Pause & Resume method during chest 4D CT using Quasar^TM Phantom. Materials and Methods : Using the Quasar^TM Phantom, set the breathing rate per minute to 15 BPM and 7.5 BPM, and set the S15 point as an irregular breathing section, and then placed OSLD to this point and use the Pause & Resume method to measure the dose of S15. CTDIvol, DLP, and ALARA-CT were used for comparative analysis of radiation dose between Pause & Resume method and Repeat-scan. In order to evaluate the stability and usability of the data applying the Pause & Resume method, the captured images were sorted by Advanced Workstation Volume Share7 and then sent to Eclipse^TM, the diameter and volume were analyzed by forming a contour on the iron ball in the Quasar^TM Phantom Results : When using Pause & Resume, the dose of OSLD measurement increased by 1.97 times in the section of S15. As a result of image evaluation, the average value of all volumes measured with and without the Pause & Resume method at 15 BPM and 7.5 BPM was 15.2 cm3±0.5%.Allthemeasuredvaluesfor the radius of iron ball were 3.1 cm regardless of whether Pause & Resume method was used or not. In the case of using Pause & Resume, 33% decreased from the lowest DLP value and 38% decreased from the highest DLP value of repeat scan, and the effective dose also decreased 32.1% from the minimum value and 37.6% from the maximum value. Conclusion: Irradiation dose was increased by Pause & Resume method because of the repeat scan on the S15 site where assuming irregular breathing occurred, However Pause & Resume method led to a significant reduction in dose on overall scan range. It also proved the usefulness of clinical application of the Pause & Resume method as a result of similar diameters and volumes of iron ball measurement.