• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.825-837
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• 1997

The purpose of this study was to evaluate the effect of splinting methods on the rearrangement of periodontal fibers after experimental tooth movement. Orthodontic force was applied by placing closed coil spring between upper third incisor and canine in seven dogs, weighing 20 kg or more. After 3 weeks of force application, 0.0215 inch multistrand wire and polyethylene ribbon were bonded to each side, as a flexible and rigid splinting respectively in 6 experimental animals. The remaining one served as a control. Each two animals were sacrificed at 4, 8 and 12 weeks after splinting respectively and prepared histologically for hematoxylin-eosin and Masson's trichrome staining. The results of this study were obtained as follows: 1. After tooth movement, periodontal space was narrowed and periodontal titers were thick on pressure side while elongated fibers were observed on tension side. 2. After 4 weeks of retention, the rearrangement of periodontal fibers was observed in the flexible splinting group, but not in the rigid splinting group. 3. After 8 weeks of retention, the rearrangement of periodontal titers was observed in both groups, but the difference could not be detected between two groups. 4. During the retention period, the rearrangement of periodontal fibers was faster in tension side than in pressure side. These results show that the rearrangement of periodontal fibers is also obtained by rigid splinting after tooth movement. It is suggested that the rigid splinting by polyethylene ribbon can be used as a way of postorthodontic retention.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.283-284
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• 2024

디지털 워터마킹은 디지털 컨텐츠에 정보를 삽입하는 기술이다. 종래의 디지털 워터마킹 기술은 견고성과 비가시성 사이에 트레이드오프 관계를 가지고, 변형 및 노이즈 공격 등에 취약하다. 본 논문에서는 호스트 이미지의 비가시성을 보장하면서 효율적인 공격 탐지와 소유자 식별이 가능한 워터마킹 기법을 제안한다. 제안한 방식은 주파수 분할 기반의 계층적 워터마킹 및 공격 탐지 시그니처 삽입을 통해 비가시성을 보장하며 용량과 견고성 측면에서 종래의 방법보다 향상된 성능을 보였다. 실험 결과에 따르면 종래의 디지털 워터마크가 무력화되는 왜곡 공격 상황에서 공격 탐지 시그니처 검출이 가능하여 워터마크 공격을 탐지하고 소유자를 식별할 수 있었다.

• Food Science and Preservation
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• v.6 no.2
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• pp.167-172
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• 1999

The noodle making characteristics were investigated for both eleven varities of Korean wheat, such as Chokwangmil, Geurumil, Eunpamil, Tnpdongmil, Woorimil, Oigeurmil, Alchanmil, Cobunmil, Geumgangmil, Seodunmil and Suwon 265, and two varieties of imported wheat, DNS(Dark Northern Spring Wheat) and ASW(Australian Standard White). After cooking of dry-noodle, the elasticities were 0.59-0.79 in the native wheat and 0.55-0.57 in the imported wheat. Among the varieties showing the highest value in the various texture properties of cooked dry-noodle, Alchanmil was highest in gumminess, Geungangmil in cohesiveness, Olgeurumil in adhesiveness, Geurumil in fimmess, Chokwang in chewiness, Tapdongmil in tensile strength Gobunmil in breaking strength. After cooking the wet-noodle, Tapdongmil in elasticity, Geurumil in adhesiveness, Geumgangmil in gumminess, cohesiveness, firmness and chewiness, and Suwon 265 in tensile strength showed the highest values in the respective textural properties. From the sensory evaluation of the cooked dry-noodle, the significant differences (p<0.05) among wheat varieties were observed in color, texture and overall quality. As a result, ASW was excellent in our all qualities of cooked dry-noodle followed by Tapdongmil, Alchanmil and Geumgangmil. The cooked wet-noodle also showed the high sensory scores (p<0.01) were showing the best in Tapdongmil, followed by Eunpamil, Geumgangmil and Woorimil.

• Journal of Korea Water Resources Association
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• v.49 no.2
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• pp.95-106
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• 2016

Water Management Resilience Index (WMRI) was developed as a policy measure of adaptability to withstand water stresses and to set up water management strategies mainly in mid-small scale tributaries, and then evaluated on 117 sub-basins in South Korea. The index consists of 3 sub-indices such as vulnerability, robustness and redundancy sub-indices, each including indicators of 3 sectors: water use, flood mitigation, and river environment. Total number of indicators selected for the index was 31. Taking into account the stream order and control capability of river flow discharge, sub-basins were categorized into 3: 1 for mainstreams of lower large dams, 2 and 3 for tributaries, respectively without and with flow discharge regulation. As a result of the evaluation, resilience index scores in Category 2 and 3 are much lower than that of Category 1, especially with very poor score of redundancy. Although there was no significant difference between mainstream and tributaries in vulnerability and robustness sub-indices, results of redundancy sub-index in tributaries were lower than those in mainstream. Thus, it is conceived that the variety of water management schemes should be considered to improve their resilience in the face of future uncertainty. Addressing comprehensive stability of river basin against internal and external impacts, WMRI in this study can also be used for the prioritization of water management plans.

• Journal of the Korea Computer Graphics Society
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• v.7 no.1
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• pp.37-49
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• 2001

We propose an optimization of mutual information for multiresolution image registration to represent useful information as integrated form obtaining from complementary information of multi modality images. The method applies mutual information as cost function to measure the statistical dependency or information redundancy between the image intensities of corresponding pixels in both images, which is assumed to be maximal if the images are geometrically aligned. As experimental results we validate visual inspection for accuracy, changning initial condition and addictive noise for robustness. Since our method uses the native image rather than prior feature extraction, few user interaction is required to perform the registration. In addition it leads to robust density estimation and convergence as applying non-parametric density estimation and stochastic multiresolution optimization.

• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.81-88
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• 1996

The effects of water to rice ratio on the properties of cooked nonwaxy and waxy rice during storage were investigated by sensory evaluation and instrumental test by Instron. The result of sensory evaluation revealed more significant difference in most of texture characteristics than flavour. As the water to rice ratio increased, the moisture content of cooked rice increased and the value of moistness and plumpness increased but that of hardness decreased. Overall eating quality was the highest in cooked nonwaxy rice with 1.4(water/rice) and in cooked waxy rice with 1.2(water/rice). In the case of instrumental test, hardness showed highly significant difference and the value of hardness of nonwaxy cooked rice was greater than that of waxy cooked rice.

• The Journal of the Korea Contents Association
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• v.5 no.2
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• pp.87-94
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• 2005

In this paper, we present a new watermarking algorithm in which a watermark is created based on the energy of the original image and embedded into the image by replacement. The watermark is adjusted to have a certain proportional amount of energy based on one of the original image and embedded into the DFT magnitude component replacing original coefficients. This scheme reduces degree of quality degradation in a watermarked image by maintaining energy and strengthen robustness against attacks by embedding a strong watermark. From the result of experiment, we confirmed that the proposed algorithm had high invisibility of 47.6dB of PSNR and could reconstruct 98.9% of message on average.

• The KIPS Transactions:PartB
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• v.11B no.2
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• pp.125-132
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• 2004

In this paper, a watermark inserting method according to the sensitivity of human visual system and minimizing distortion of original DCT coefficients in DCT transform domain is proposed. The proposed method inserts a more robust watermark in the insensitive block of human vision by reordering the blocks according to the human visual system which is appropriate to the JPEG image compression. It also enhances the invisibility and robustness in high compression rate in terms of the watermark inserting method within the block which minimizes distortions of original DCT coefficients. The computer simulation results show that the proposed method maintains high image quality and good robustness in high compression rate compared with conventional watermarking method.

• Food Science and Preservation
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• v.6 no.4
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• pp.429-434
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• 1999

This study was undertaken to investigate preparation possibility of chestnut mooks added chestnut shell. Three types of chesetnut starches which were flesh starch(FS), inside shell containing starch(ISS), and shell containing starch(SCS) and acorn starch(AS) as control were used to preparation of mook. The crude tannin contents of chestnut starches was about 25% of that in acorn starch. In the textural properies, hardness of mooks was increased in proportion to the increasing concentration of starches. Hardness md cohesiveness of mooks with chesnut starches were higher than those of acorn starch. Color properties of mooks with OSS were similar to that of AS. Sensory evaluation by 9-point method indicated that the nooks with ISS had greater intensities in all investigation items. The total scores were higher in order of ISS, AS, FS and SCS. The mook with ISS had homogeneous and porous structure by SEM.

• Journal of KIISE:Software and Applications
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• v.28 no.3
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• pp.262-271
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• 2001

디지털 컨텐츠의 저작권 보호와 위변조 탐지를 위해 사용되는 비가시적인 워터마킹 기법은 워터마킹된 영상의 화질저하를 최소로 하면서 화질이 현격히 저하되기 전에는 워터마크가 제거되지 않는 견고성을 갖도록 해야한다. 본 논문에서는 워커마킹된 영상에서 원영상을 사용하지 않고 저작권자를 탐지할 수 있는 디지털 워터마킹 기법을 제안한다. 제안된 기법은 크게 내장단계와 탐지단계로 나뉜다. 내장단계에서는 워터마킹된 영상의 화질이 크게 저하되지 않도록 시각적 마스킹 효과를 고려한다. 워터마크 탐지과정은 원 영상을 사용하지 않고 저작권 분쟁이 발생한 영상과 저작권 주장하는 사람이 제시한 해당 워터마크만을 사용하여 이루어진다. 본 논문에서 제안된 디지털 워터마킹 방법은 일반적인 영상의 변형에 상당히 견고한 특성을 가지며, 변형이 가해지지 않은 워터마킹된 영상을 저작자가 보관함으로써 다중 소유권 주장 문제에 대해서도 저작권 주장이 가능하다.