• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.1
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• pp.136-140
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• 2015

Linux environment that is commonly used at embedded systems supports various file systems as Ext2, FAT, NTFS, etc. The file system that is equiped on the embedded system is mostly implemented on mini hard disk or flash memory. The types of the file system of the system make an effect on the performance of a application programs. The factors of file system performance on a same media are block read, block write and block free time. On these factors, block read and block free time are not so different according to the type of file systems. This paper evaluates the performance benchmark of file systems supported by linux about block allocation and write performance. The results obtained from various experiments shows the characteristics of each file system.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.2
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• pp.85-96
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• 2008

One of the typical methods to prevent tampering and reverse engineering on executable codes is to encrypt them. This paper proposes a code block cipher method based on key chaining to encrypt the code. The block cipher by key chaining has been known to be inadequate for encrypting the code with control transfer, even though the key chaining has advantage of hiding the keys in blocks and making the individual keys different from block to block. This paper proposes a block transformation and duplication method to apply the block cipher by key chaining to the executable codes with control transfer instructions, and shows the idea works with the MIPS instruction set.

• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.185-190
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• 2010

In this paper we propose the CBIR algorithm which is based on a novel image block method that combined both color and edge feature. The main drawback of global histogram representation is dependent of the color without spatial or shape information, a new image block method that divided the image to 8 related blocks which contained more information of the image is utilized to extract image feature. Based on these 8 blocks, histogram equalization and edge detection techniques are also used for image retrieval. The experimental results show that the proposed image block method has better ability of characterizing the image contents than traditional block method and can perform the retrieval system efficiently.

• The Korean Journal of Pain
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• v.3 no.1
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• pp.15-20
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• 1990

Three hundred and eighty-nine cases of splanchnic nerve block were retrospectively divided into 3 groups according to the change of alcohol concentration. In Group 1 (26 cases), about 7 ml of 1% lidocaine was used bilaterally as test block followed by an injection of 20 ml of 50% alcohol bilaterally. In Group 2 (286 cases) the same test block was followed by the same amount of pure and 50% alcohol. In Group 3 (77 cases) and used 30 ml of 75% alcohol bilaterally. The overall success rate of the first alcohol block in group 1, 2 and 3 was 73.1%, 92.0% and 84.4% respectively. From the above results, that splanchnic nerve block by pure alcohol was the most reliable method for upper abdominal cancer patients.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.75
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• pp.137-158
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• 2017

Traditional banking systems of transactions are being replaced by FfinTech. Block Chain System can be a key point in Fourth Industrial Revolution such as AI, Big Data, IOT and also can be used as a tools of smart contract or smart payment systems in International Trade. If banking regulation is to be liberalized FinTech would be more activated in Korea and various attempts would be available especially smart payment in business. There are so many levels to be achieved from the time of contract to the time of clearance. We cannot expect speed and range of IT advancement and international trade, Block Chain system will challenge the traditional banking process. First, Block Chain Payment system can be used in P2P, B2B transaction and also T/T in small business. Second, Bit Coin transaction can be available within the parties without the Trusted Third Party. Third, By using of Block Chain system Traditional International Trade process can be altered.

• Macromolecular Research
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• v.14 no.4
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• pp.424-429
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• 2006

The synthesis of a series of poly(POSS-NBE-b-MTD) copolymers was successfully accomplished, taking advantage of sequential, ring-opening, metathesis block copolymerization using $RuCl_2(=CHPh)(PCy_3)_2$ catalyst. By using cyclopentyl-POSS-norbornene (POSS-NBE) monomer as the first block in the block copolymer, living poly(POSS-NBE) with controlled molecular weight and narrow molecular weight distribution was produced. Then, poly(POSS-NBE-b-MTD) copolymers were successfully prepared, in which sequential monomer addition of methyltetracyclododecene (MTD) to the living poly(POSS-NBE) chain ends was utilized to achieve quantitative crossover efficiency. Characterization by $^1H$ NMR spectroscopy and GPC confirmed the high definition and structural integrity of the poly(PO$S-NBE-b-MTD) copolymers. Thermal properties-and morphologies of the POSS-containing block copolymer nanocomposites were also investigated by using thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and wide-angle X-ray scattering (WAXS).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.1
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• pp.76-81
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• 2018

This study aims to provide ways to achieve structural improvements of the internal flow path of the discharge plenum of a swash plate piston pump valve block vulnerable to cracks. This paper corresponds to Part II, which consists of a structural interpretation of the internal flow path of the discharge plenum of the valve block. The simple model result reviewed in Part I was incorporated into the valve block model and five different design changes were reviewed as part of the study on the structural improvement of the internal flow path of the valve block.

• The Korean Journal of Pain
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• v.6 no.2
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• pp.258-260
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• 1993

We experienced a rare case of erection failure which developed after unilateral lumbar sympathetic block. A 43 year old male patient suffering from reflex sympathetic dystrophy, which had developed after multiple communitted fracture of the right ankle, underwent right lumbar sympathetic block with 99.9% alcohol. The effectiveness of the lumbar sympathetic block was evaluated by monitoring the clinical symptoms, signs and temperature changes by digital infrared thermographic imaging. Postoperatively, the temperature of the affected side limb rose about $2^{\circ}C$, but the patient's conditions gradually returned to normal. Ten days after the operation the patient complainted of difficulty in achieving an erection. The patient was examined by a urologst without much results. The patient gradually recovered his ability to achieve an erection approximately 5 weeks after the lumbar sympathetic block.

• The Korean Journal of Pain
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• v.2 no.1
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• pp.85-88
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• 1989

We experienced 3 cases of continuous caudal block. The first case had suffered from severe pain of the external genitalis after urethral injury from a car accident and this was controlled by continuous caudal block. The other 2 cases were a metastaric malignant tumor of the lumbar vertebra from cancer of the cervix and histiocytoma of the breast, and both had suffered from intractable pain of the lower extremity. But lumbar epidural block was impossible because of radiation fibrosis and previous operation scar of the spine. So a continuous caudal block was performed and the pain was controlled effectively. The longest duration was 50 days and there were no problems related catheter indwelling. Pain in the area of the lumbar and sacral nerve distribution can be controlled by continuous caudal block. Here in we reported 3 cases and reviewed the literature.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.675-684
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• 1997

The bit rate control algorithm which is capable of handing scene change is proposed. In MPEG-2 TM5, block variance is used to measure block activity. But block variance is not consistent with human visual system and does not differenciate the distribution of pixel values within the block. In target bit allocation process of TM5, global complexity, obtained by results of previous coded pictures, is used. Since I pictures are spaced relatively far apart, their complexity estimate is not very accurate. In the proposed algorithm local variance is used to measure block activity and detect scene change. Local variance, using deviation from the mean of neighboring pixels, well represents the distribution of pixel values within the block. If scene change is detected, the local variance information is used for target bit allocation process. Allocating target bits for I picture, the average local variance difference between previous and current I picture is considered. The experimental results show that the proposed algorithm can detect scene change very precisely and gives better picture quality and higher PSNR values than MPEG-2 TM5.