• Journal of the Korean Arthroscopy Society
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• v.8 no.2
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• pp.89-93
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• 2004

Purpose: To evaluate the clinical stability and function after arthroscopic anterior cruciate ligament(ACL) reconstruction using fresh-frozen tibialis tendon allograft. Materials and Methods: Of the patients who underwent ACL reconstruction using tibialis tendon allograft from July 2002 to June 2003, thirty-one patients could be evaluated and the mean follow-up period was 19 months. Evaluations included were Lysholm knee score, 2000 International knee Documentation Committee (IKDC) subjective knee score, Lachman test, pivot shift test, KT-1000 arthrometer measurement and 2000 IKDC knee examination. Results: The mean Lysholm score was 88. Twenty-eight patients (90.3%) were good or exellent for the measured parameters. Twenty-seven patients(87.1%) was over 70 in IKDC subjective knee score. Thirty patients (96.8%) had 1+ firm end or negative Lachman test. 27 patients (87.1%) had a negative pivot shift. Thirty patients (96.8%) had less than 5mm difference of maximal manual difference by KT-1000 arthrometer. Twenty -nine patients (93.5%) were nearly normal or normal grade by 2000 IKDC knee examination. Complications were 1 case of failure and 1 case of infection. Conclusion: ACL reconstruction with the double-stranded fresh-frozen tibialis tendon allograft resulted in a reliable and predictable outcome after short-term follow-up.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.574-580
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• 2014

Storage tanks of Carbon dioxide ($CO_2$) carriers utilized for the purpose of carbon capture and storage (CCS) into subsea strata have to undergo a pre-cooling session before beginning to load cryogenic liquid cargos in order to prevent physical and thermal deterioration of tanks which may result from cryogenic $CO_2$ contacting tank walls directly. In this study we propose dynamic model to calculate the tank inflow of $CO_2$ gas injected for precooling process and its dynamic simulation results under proportional-integral control algorithm. We selected two cases in which each of them had one controlled variable (CV) as either the tank pressure or the tank temperature and discussed the results of that decision-making on the pre-cooling process. As a result we demonstrated that the controlling instability arising from nonlinearity and singularity of the mathematical model could be avoided by choosing tank pressure as CV instead of tank temperature.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.255-255
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• 2016

Resistive random access memory (ReRAM)는 낮은 동작 전압, 빠른 동작 속도, 고집적화 등의 장점으로 인해 차세대 비휘발성 메모리 소자로써 많은 관심을 받고 있다. 최근에 ReRAM 절연막으로 NiOx, TiOx, AlOx TaOx, HfOx와 같은 binary metal oxide 물질들을 적용하는 연구가 활발히 진행되고 있다. 특히, HfOx는 안정적인 동작 특성을 나타낸다는 점에서 ReRAM 절연막 물질로 적합하다고 보고되고 있다. ReRAM 절연막을 형성할 때, 물리 기상 증착 방법 (PVD)이나 화학 기상 증착법 (CVD)과 같은 방법이 많이 이용된다. 이러한 증착 방법들은 고품질의 박막을 형성시킬 수 있는 장점이 있다. 하지만, 높은 온도에서의 공정과 고가의 진공 장비가 이용되기 때문에 경제적인 문제가 있으며, 기판 또는 금속에 플라즈마 손상으로 인한 문제가 발생할 수 있다. 따라서 이러한 문제점들을 개선하기 위해 용액 공정이 많은 관심을 받고 있다. 용액 공정은 공정과정이 간단할 뿐만 아니라 소자의 대면적화가 가능하고 공정온도가 낮으며 고가의 진공장비가 필요하지 않은 장점을 가진다. 따라서 본 연구에서는, 용액공정을 이용하여 HfOx 기반의 ReRAM 제작하였고 $25^{\circ}C$와 $85^{\circ}C$에서 ReRAM의 동작특성에 미치는 compliance current의 영향을 평가하였다. 실험 방법으로는, hafnium chloride (0.1 M)를 2-methoxyethanol에 충분히 용해시켜서 precursor를 제작하였다. 이후, p-type Si 기판 위에 습식산화를 통하여 300 nm 두께의 SiO2 절연층을 성장시킨 후, 하부전극을 형성하기 위해 electron beam evaporation을 이용하여 10/100 nm 두께의 Ti/Pt 전극을 증착하였다. 순차적으로, 제작된 산화물 precursor를 이용하여 Pt 위에 spin coating 방법으로 1000 rpm 10 초, 6000 rpm 30초의 조건으로 두께 35 nm의 HfOx 막을 증착하였다. 최종적으로, solvent 및 불순물을 제거하기 위해 $180^{\circ}C$의 온도에서 10 분 동안 열처리를 진행하였으며, 상부 전극을 형성하기 위해 electron beam evaporation을 이용하여 Ti와 Al을 각각 50 nm, 100 nm의 두께로 증착하였다. ReRAM 동작에서 compliance current가 미치는 영향을 평가하기 위하여 compliance current를 10mA에서 1mA까지 변화시키면서 측정한 결과, $25^{\circ}C$에서는 compliance current의 크기와 상관없이 일정한 메모리 윈도우와 우수한 endurance 특성을 얻는 것을 확인하였다. 한편, $85^{\circ}C$의 고온에서 측정한 경우에는 1mA의 compliance current를 적용하였을 때, $25^{\circ}C$에서 측정된 메모리 윈도우 크기를 비슷하게 유지하면서 더 우수한 endurance 특성을 얻는 것을 확인하였다. 결과적으로, 용액공정 방법으로 제작된 ReRAM을 측정하는데 있어서 compliance current를 줄이면 보다 우수한 endurance 특성을 얻을 수 있으며, ReRAM 소자의 전력소비감소에 효과적이라고 기대된다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.5
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• pp.529-541
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• 2020

Although TBM's cutterhead requires design review for fatigue failure due to wear-induced section loss as well as heavy load during excavation, it is difficult to find a case of fatigue analysis for TBM cutterhead at present. In this study, a stress-life design review was conducted on cutter heads with a diameter of 8.2 m using S-N curves as a safety life design concept. Also, we introduced the fatigue design method of construction equipment and the method of assessing fatigue damage and explained the results of the fatigue analysis on the TBM cutter head with a diameter of 8.2 m. The S-N curve has been shown to play a key role in fatigue design and can also be used to assess how much fatigue damage a structure is suffering from at this point in time. In the future, it is necessary to find out when fatigue problems occur during using the equipment and when it is good to conduct safety inspections of the equipment.

• Journal of Conservation Science
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• v.29 no.4
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• pp.395-406
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• 2013

The conservation of damaged object should be restored by the similar material with the original and they have to reversibility as possible as. The characteristics of Buddhist mural paintings composed of clay are with soft material. So far, there have been a number of researches done on filling material that reinforces cracks and exfoliation of mural painting. Based on the application of traditional materials, it was found that they are appropriate to various applications. However, only based on those research results, there are some constraints to the application in the field. In addition, there has been only a few researches done on physical characteristics of filling materials. A major issue is that there is not any standard established on various mixing ratio, which is required for treatment of mural painting. This study was carried out to understand the physical characteristics of filling materials on clay mural painting. The 1st test was conducted to analyze test specimen in twelve different conditions by varying soil mixing ratio and organic medium. The 2nd test was conducted to manufacture filling materials appropriate to the mural painting, based on the result of stable condition from the 1st test, and which was applied to treatment in field.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.353-358
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• 1983

This study indicated that mackerel flesh can be prepared as an intermediate moisture deep-fried product. The fillet were cut into $2{\times}2{\times}1.5cm$ (about 4g each): then submerged in an infusion solution (lg flesh: 1ml solution) containing 45.9% of water, 6% of sodium chloride, 40% of sorbitol, 2.4% of propylene glycol, 0.7% of potassium sorbate, 3% of sugar, 2% of monosodium glutamate, and $0.6m{\ell}$ of alcoholic extracts from red pepper, and heated for 10 min at $105^{\circ}C$. The infused flesh was drained for 15 min and then coated with batter and crumb. The pieces were deep fried in soybean oil for 3 min at $170^{\circ}C$ and cooled on absorbent paper. The initial water activity of the product was 0.86. Judging from the results of experimental data such as peroxide value, TBA value, viable cell count and sensory evaluation, the quality of products were stable for 50 days at room temperature ($25{\pm}2^{\circ}C$).

• Korean Journal of Social Welfare
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• v.63 no.1
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• pp.267-289
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• 2011

The purpose of the present study was to develop a Korean version of the scale of attitudes for disabled Persons and attitudes towards disabled person-original by translating and modifying the scale proposed by Antonak(1982). In order to test validation, this study was focused on processing survey and statistic data analysis and tried to find a way to applicate in Korea. The data were collected from 500 non-disabled persons divided into two groups, which were consist of target group (public officials, health care providers, teachers, journalists and rehabilitation facility staffs) and general group. Based on the descriptive analysis, exploratory factor analysis and confirmatory factor analysis of the data, validity and reliability were examined. Also to find the statistic significant difference on attitudes towards disabled person between target group and general group, t-test was proceed. The result of the exploratory factor analysis drew 15 items representing 3 factors (Pessimism-Stereotype, Optimism-Human Rights, Derogatory Personality Stereotype). A confirmatory factor analysis results provided the construct validity of this scale as good and reasonable fitness. Cronbach's alpha ranged from .67 to .85 showed internal consistencies of the sub-scales. The subscales were significantly correlated with convergent with DFS(Disability Factor Scale) variables. And the target group had more positive attitudes toward disabled person than general group. It is suggested this scale more suitable for various disability types be elaborated, and get a practical implication on attitudes towards disabled person.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.37-44
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• 2018

This study proposed the modified weighting values for jointed rock slopes. The studies on deduction of evaluation index and calculation of weighting, development of criteria for evaluation and evaluation models have been conducted through decision making techniques such as the Delphi method and the AHP method by many researchers. Because these decisions making techniques may be less objective, it is necessary to calculate reasonable weighting considering both an objective weighting and a subjective weighting simultaneously. In this study, utilizing the inspection data of jointed rock slopes, an objective weighting that the concept of entropy is applied was calculated. And the subjective weighting values by AHP technique was calculated based on the opinion of experts. And a modified weighting was suggested by combining the two. As a result, it was found that jointed rock slopes have higher weighting in artificial factors and the damage status items. In addition based on the finally suggested weighting (mixed weighting), the revised evaluation criteria could be presented by converting it into the evaluation score (76 points). And it is expected that it could be usefully utilized upon inspections on cutting slopes and safety diagnosis since objective and highly reliable criteria compared to the condition evaluation criteria that are currently used could be presented through the results of the study.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.2
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• pp.155-161
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• 2019

Currently, numerous companies and institutes provide services using the Internet, and establish and operate Information Systems to manage them efficiently and reliably. The Information System implies the possibility of losing the ability to provide normal services due to a disaster or disability. It is preparing for this by utilizing a disaster recovery system. However, existing disaster recovery systems cannot perform normal recovery if files for system recovery are corrupted. In this paper, we proposed a system that can verify the integrity of the system recovery file and proceed with recovery by utilizing hyper-ledger fabric blockchain. The PBFT consensus algorithm is used to generate the blocks and is performed by the leader node of the blockchain network. In the event of failure, verify the integrity of the recovery file by comparing the hash value of the recovery file with the hash value in the blockchain and proceed with recovery. For the evaluation of proposed techniques, a comparative analysis was conducted based on four items: existing system recovery techniques and data consistency, able to data retention, recovery file integrity, and using the proposed technique, the amount of traffic generated was analyzed to determine whether it was actually applicable.

• Journal of Life Science
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• v.34 no.8
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• pp.594-607
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• 2024

Plastic products have long been widely used in both industrial and household applications. However, tiny plastic particles derived from plastic products, such as microplastics (MPs) and nanoplastics (NPs), can infiltrate the human body through inhalation, ingestion, or skin contact. Once inside cells via endocytosis, MPs and NPs (MNPs) can trigger autophagy, but lysosomal dysfunction can block autophagic flux. Accumulating in the cytoplasm, these particles induce cellular stress, including oxidative stress from free radicals, mitochondrial dysfunction, and increased inflammatory response. Meanwhile, cellular senescence is a hallmark of aging and is defined as the stable termination of the cell cycle in response to cell damage and stress. In particular, the accumulation of oxidative stress, a key factor in inducing cellular senescence, induces the expression of major senescence markers. Senescent cells increase the secretion of senescence-associated secretory phenotype, including inflammatory cytokines and chemokines. Despite growing interest in how MNPs induce cellular senescence, there remains a gap regarding their onset and therapeutic targets. Therefore, this review focuses on identifying recent research trends on how MNPs induce cellular aging in key human cell types and proposes future research directions to overcome these challenges.