• Applied Microscopy
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• 제32권4호
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• pp.361-376
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• 2002

This research was conducted to determine the effects of chitosanoligosaccharide on liver poisoning induced by cadmium (Cd). Three groups of mice were used in this research. The group was only injected with cadmium (5.0 mg/kg; i.p.) (group Cd) and the other group was injected with cadmium and chitosanoligosaccharide (0.5% solution) at the same time (group Cd+Chi). In order to investigate the inhibitory action of chitosanoligosaccharide on liver damage, cadmium concentration in liver tissues and metallothionein (MT) concentration were relatively measured. In addition, histological observations were made to determine the morphologic injury of liver tissues. Cadmium concentration in liver tissues was drastically lower in groups Cd+Chi than in group Cd. MT concentration in liver tissues was lower in group Cd than in groups Cd+Chi. As the result of electron microscopic observation, mitochondria in group Cd showed a severe swelling phenomenon, RER fragment and ribosome dropout. However, in groups Cd+Chi, mitochondria with high electron density were distributed and RER forming a typical lamellae with ribosome was observed. From these results, cadmium toxicity on rat liver tissues could be lessened by chitosanoligosaccharide.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제34권11호
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• pp.1727-1732
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• 2010

Forensic engineering is the area of expertise of people qualified to serve as engineering experts in courts of law or during arbitration proceedings. An aerial-lifter can lift and carry load, including people, using power. Recently, failure of aerial-lifter internal parts while working and sweeping causing injuries and damage to property almost always generates conflict between the automaker and customer. Hence, the investigation of such events generally involves an engineering analysis. One of the possible reasons for accidents, such as a vehicle catching fire is the failure of oil pressure machine and the supporting pin. The results of formal inspections and engineering tests can reveal the cause for the failure of the mechanical parts. Therefore, the failure mechanism is analyzed by adopting fractography methods and by applying an instrumented indentation technique to compare the material properties of the reference part with those of the malfunctioning part.

• Journal of the Korean Arthroscopy Society
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• 제6권2호
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• pp.156-160
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• 2002

Purpose : To evaluate the results and usefulness of meniscal repair using meniscal arrows with ACL reconstruction. Material and Methods : Among cases of the simultaneous meniscal arrow fixation and ACL recontruction performed between May, 1997 and September, 2000, 17 cases could be evaluated. The average follow-up were 18.5 months. Twelve cases were medial meniscus, 5 cases, lateral meniscus. All cases were longitudinal tear. Meniscal tear were seen at red-red zone in 13 cases, red-white zone in 5 cases. The results were analyzed by pain, joint line tenderness, locking, McMurray test, the Marshall knee scoring scale and complications. Results : Postoperatively two patients had mild joint line tenderness without pain on joint motion or weight bearing. No patient had locking or positive McMurray test. At last follow-up, 15 cases $(88\%)$ were 'excellent' or 'good' according to the Marshall knee score scale. There were two complications which are soft tissue irritation sign on active knee motion and a femoral chondral injury due to protruded T-shaped head of meniscus arrow. Conclusion : Meniscus arrow can be one of the options in repairing the associated meniscus tear, especially the posterior horn of medial meniscus, during ACL reconstruction. However, surgeons using meniscus arrow should be aware of its potential complications such as pain due to soft tissue irritation and chondral damage of the femoral condyle.

• Journal of Conservation Science
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• 제30권4호
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• pp.427-438
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• 2014

To measure the depth and extension on the surface cracks of the stone monument, ultrasonic pulse velocity targeted at the Mulgyeseowon Stele in Changnyeong was used in this research. Additionally, to establish a long-term countermeasure of management and conservation for this stele, we have investigated the material properties and damage on it and have conducted a precise diagnosis by a variety of non-destructive techniques. Our research has revealed that stones of the stele are composed mainly of three rock types according to the parts of it, alkali-feldspar granite, gabbro and diorite. The result of the deterioration evaluation has occurred that cracks, which are observed from every direction in the body of the stele, are the significant factors to reduce structural stability. The ultrasonic velocity for an evaluation on the properties of the stele has revealed that the speed was high in the order of body, pedestal and crown. Furthermore, to understand the present condition and occurrences of the cracks which have measured in many different forms on the stele quantitatively, we have estimated from 0.6 to 24.1cm deep of the cracks by To-Tc method using ultrasonic velocity.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제43권2호
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• pp.149-155
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• 2017

This study was carried out to investigate the hair protection effect of fermented black soybean extracts. The morphological characteristics, tensile strength and constitutional changes of the hair were analyzed and compared when the hair was chemically oxidized and then treated with fermented black soybean extract. As a result, treatment of oxidizing agent on virgin hair caused damage on the cuticle layer of the epidermis and decreased in tensile strength of hair from $14.32{\pm}0.83g/cm^2$ to $12.32{\pm}0.79g/cm^2$. FT-IR analysis showed the peaks at 1,077, 1,041, and $801cm^{-1}$ of the hair treated with oxidizing agent were increased compared to peak values of virgin hair, indicating that cystein in hair was decreased which is crucial to disulfide bond between keratin. On the other hand, when the damaged hair is treated with the fermented black soybean extract, cracks in the cuticle layer of the epidermis were filled, tensile strength was restored to $14.27{\pm}0.96g/cm^2$ and the ratio of oxidized cysteine in hair was decreased. These results suggest that the fermented black soybean extract is worthy of further investigation as a protective material for hair damaged by oxidizing agents.

• Economic and Environmental Geology
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• 제56권6호
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• pp.675-695
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• 2023

The tracksite of dinosaurs and pterosaurs in Sanbuk-dong of Gunsan is the largest early Cretaceous dinosaur footprint fossil site in Korea, and all the footprints are important evidence indicating that large ornithopod and theropod dinosaurs inhabited the Korean peninsula during the early Cretaceous. The Sanbuk-dong site was covered with waterproof sheet in an outdoor environment until the installation of a protective enclosure in 2021. As a result, various factors such as shear force, load reduction, temperature and humidity fluctuations, acid rain, salinity and microorganisms have complexly interacted in the substrate of fossils, exacerbating the damage to footprints. For 159 footprints in 12 trackways among the footprints found in the site, the damage types were classified in detail and the level of each damage was assessed. The damages were classified into 6 types through the classification of deterioration degree of individual footprints. As a result of ultrasonic physical property evaluation on the surface of the fossil site, most of these footprints are in the completely weathered (CW) stage. Furthermore, various weathering patterns were observed in the study area, and surface contaminants were analyzed along the stratigraphy. Although the patterns of freshness and contaminants varied at different points within the fossil site, the chemical compositions were similar. Based on the results, an efficient conservation management system for dinosaur footprint fossils was established, and a conservation treatment type for each footprint was proposed.

• Proceedings of the KACD Conference
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• 대한치과보존학회 2002년도 춘계학술대회
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• pp.322-322
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• 2002

치경부 병소는 부적절한 칫솔질, 화학적 침식 및 차아의 굴곡 등의 여러 원인에 의해 크게 cervical abrasion, erosion 및 abfraction의 형태로 나타난다. 최근 노령 환자층의 증가와 치주 치료에 의한 구강내 치아 잔존율의 증가는 치경부 병소의 증가를 가져왔다. 이러한 치경부 병소는 지각과민증, 우식 및 심미적 이유 등으로 수복을 시행하며 구치부위에 작은 우식이 없는 치경부 병소가 있는 경우 환자에게서 지각과민증를 유발하지 않는 경우라면 수복을 시행하지 않을 수도 있지만, 많은 예에서 더 이상의 치아 및 치주 조직의 손상을 억제하고 치수의 보호를 위해서 수복을 시행한다. 특히 전치부의 경우에는 병소가 작고 우식에 이완되지 않았다 할지라도 그 심미적 측면 때문에 수복을 시행하는 예가 증가하고 있다.(중략)

• Journal of the Korean Institute of Intelligent Systems
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• 제13권5호
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• pp.539-544
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• 2003

The weapon-target assignment problem is solved using a genetic algorithm in this paper. The weapon-target assignment is an optimization problem which minimizes damages from enemy s attack or maximizes the kill probability of targets. Genetic algorithm is applied in this paper since it usually converges to a near global optimal solution. A specific structure of genetic algorithm which is suitable for the weapon-target assignment problem is proposed. A guideline selecting associated parameters is investigated through simulations. Comparition of the proposed method with several traditional optimization techniques for the weapon-target assignment problem shows the validity of the proposed method.

• The KIPS Transactions:PartB
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• 제18B권6호
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• pp.385-388
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• 2011

Patients' privacy protection is a heated issue in medical business, as medical information in digital format transmit everywhere through networks without any limitation. A current protection method for brain images is to deface from the brain image for patient's privacy. However, the defacing process often removes important brain voxels so that the defaced brain image is damaged for medical analysis. An ad-hoc method is proposed to conceal patient's identification by adding cylindrical mask, while the brain keep all important brain voxels. The proposed lossless deformation of brain image is verified not to loose any important voxels. Futhermore, the masked brain image is proved not to be recognized by others.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 한국전산구조공학회 2009년도 정기 학술대회
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• pp.442-445
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• 2009

지진에 대한 건축물의 확률적 성능평가에 대해서는 지진하중에 대한 건축물의 손상확률 또는 파괴확률을 나타내는 지진취약도 함수를 작성하여 대상 건축물에 대한 지진위험도를 평가하는 방법을 이용하고 있으며 이에 대한 많은 연구가 이루어지고 있다. 본 연구에서는 지진하중과 구조물 재료특성의 불확실성을 고려하고 대상 건축물의 지진취약도 해석을 통하여 비내력벽의 유무에 따른 건축물의 지진거동 및 내진성능을 평가하였다. 비내력벽을 보편화된 모형화 방법인 등가의 대각 압축 스트럿으로 고려하여 비내력벽의 유무에 따른 저층 철근콘크리트 건축물을 모형화하였으며 지진하중의 강도는 유효최대지반가속도를 이용하여 각 건축물에 대하여 지진취약도를 작성하였다. 취약도해석 결과로 연약층을 가지고 있는 건축물의 경우는 손상확률이 골조만 있는 경우보다 크며 동일한 해석모델의 경우에도 해석방법에 따라서 취약도 곡선의 형태가 다름을 알 수 있었다.