• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.2
• /
• pp.331-337
• /
• 2001

The effect of Phellinus linteus methanol extract on the lipid metabolism in the liver of rat was investigated in this study. Rats were randomly divided into 6 groups including the control, $CCl_4$and high fat group plus sub-groups with Phellinus linteus methanol extract administration. Methanol extracts of Phellinus linteus were fed 50mg/kg B.W daily via drinking water. A 1.2mL of $CCl_4/kg$ body weight was administered by oral intubation twice a week for total six times. The administration of $CCl_4$ increased total cholesterol, TG, LDL and LDL-phospholipid. However, the level of liver cholesterol and triglycerides were significantly decreased while HDL-cholesterol was increased by the extract feeding. The activities of GOT, GPT, AP and LDH were greatly enhanced by the extract feeding. Electronmicrograph showed that $CCl_4$ treatment deteriorated the structure of cytoplasmic matrix with its uneven distribution. However, the extract treatment reconstituted the damaged cytoplasm and stimulated mitochondriagenesis. From these results, it was suggested that Phellinus linteus can help to recover the damaged liver function and further may help to prevent senescence diseases such as fatty liver, hypertension and hyperlipidemia.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.16 no.4
• /
• pp.25-33
• /
• 2012

In electric power transmission tower structures on offshore, implementation of life management using the event data of regular safety inspections for structural and material damages is strongly recommended. In this study, six tower structures in Sihwa Lake around Yeoungheung island were target bodies for the safety inspections. safety inspections for deterioration about each of six towers were performed about three items for steel member, five items for concrete foundation, and four items for steel-pipe pile in seawater and seawater itself. Safety inspections for steel members included the visual observations of surface appearances, the measurements of member thicknesses, and the checks of painting states. Also safety inspections for concrete foundations comprised the estimation of crack features, the evaluation of non-destructive compression strengths, and the measurements of neutralization depths and chlorides contents. For steel-pipe piles in seawater the inspections comprised the surveys of corrosion states in accordance with potential levels tests and anode tests, the analyses of photos taken on surfaces of the piles as well as the evaluation of seawater quality. A set of deterioration inspections was performed at the same positions around october of each year for three consecutive years. As a result in this study, Newly developed deterioration indexes have been applied profitably to maintain structural safety for electric power transmission towers by utilizing these event data systematically.

• Journal of Life Science
• /
• v.27 no.9
• /
• pp.1078-1085
• /
• 2017

Free radicals have long been considered damaging to various tissues. An excessive amount of reactive oxygen species (ROS) is known to have detrimental effects on the body and to be linked to numerous pathological conditions, such as cardiovascular disease, cancer, diabetes, and skeletal muscle atrophy. On the other hand, recent findings suggest that ROS is important for maintenance and development of cellular activity. Cells respond to increased oxidative stress by adaptive changes in the expression of a variety of proteins involved in the maintenance of cellular integrity. ROS is also essential for skeletal muscle function and metabolism. It is well known that physical exercise has many health benefits. Paradoxically, physical exercise also stimulates the production of ROS, which result in oxidative stress. Based on evidence amassed in the past decade, exercise itself may be considered an antioxidant because training increases the expression of antioxidant enzymes. In this review, we discuss the processes underlying the generation of ROS and its role in exercise-induced adaptation based on recent evidence. Furthermore, we discuss the possible role of NADPH oxidase in exercise-induced activation of insulin signaling and its effect on longevity.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.5
• /
• pp.171-182
• /
• 2022

The safe use of a structure requires it to be maintained in an undamaged state. Thus, a typical factor that determines the safety of a structure is a crack in it. In addition, cracks are caused by various reasons, damage the structure in various ways, and exist in different shapes. Making matters worse, if these cracks are unattended, the risk of structural failure increases and proceeds to a catastrophe. Hence, recently, methods of checking structural damage using deep learning and computer vision technology have been introduced. These methods usually have the premise that there should be a large amount of training image data. However, the amount of training image data is always insufficient. Particularly, this insufficiency negatively affects the performance of deep learning crack detection algorithms. Hence, in this study, a method of augmenting crack image data based on the image translation technique was developed. In particular, this method obtained the crack image data for training a deep learning neural network model by transforming a specific case of a asphalt crack image into a concrete crack image or vice versa . Eventually, this method expected that a robust crack detection algorithm could be developed by increasing the diversity of its training data.

• Journal of the Korean Electrochemical Society
• /
• v.26 no.3
• /
• pp.35-41
• /
• 2023

The carbon-coated silicon monoxide (c-SiO_x), which is a negative electrode active material for lithium-ion batteries (LIBs), has a limited cycle performance due to severe volume changes during cycles, despite its high specific capacity. In particular, the significant volume change of the active material can deform the electrode structure and easily damage the electron transfer pathway. To improve performance and mitigate electrode damage caused by volume changes, we replaced parts of the carbon black conducting agent with carbon nanotubes (CNTs) having a linear shape. The content of the entire conductive material in the electrode was fixed at 10% by mass, and the relative content of CNTs ranged from 0% to 25% by mass to prepare electrodes and evaluate electrochemical performance. As the CNT content in the electrode increased, both cycle life and rate capability improved. Even a small amount of CNT can significantly improve the electrochemical performance of a c-SiO_x negative electrode with large volume changes. Furthermore, dispersing CNTs effectively can lead to achieving the equivalent performance with a reduced quantity of CNTs.

• Composites Research
• /
• v.13 no.3
• /
• pp.58-66
• /
• 2000

CARALL(Carbon fiber reinforced aluminum laminates) was fabricated with CFRP prepreg and A17075, using a autoclave. The mechanical properties of three samples i.e. A17075, CFRP and CARALL were also investigated as a function of size in circular holes. Theoretical approach into analysing mechanical behaviors near the circular hole notch was carried out to compare with experimental data, furthermore. By the adhesive bonding of A17075 to CFRP, abrupt strength reduction was prevented. From the consideration of modified point stress failure criterion, predicted results was well consistent with the experimental one.

• Restorative Dentistry and Endodontics
• /
• v.24 no.1
• /
• pp.116-128
• /
• 1999

치근흡수 연구에서 치아재식을 위한 적당한 동물모델을 찾는일은 대단히 중요하다. 본 실험에서는 쥐 대구치의 발치 및 재식을 통해서 치근흡수가 발현되는 모양을 관찰했다. 모두 20마리의 쥐(30일생)에게 0.4% ${\beta}$-APN(aminoproprionitrile)가 포함된 분말용쥐사료를 5일간 먹인후 케타민 마취후 상악좌우측 제일대구치를 손상을 최소화하여 발치 하였다. 발거된 쥐치아는 0.02M Tris-HCl로 표면처리하여 부착치근막을 제거한후 파라핀팍스로 치근단을 밀폐 하여 재식하였다. 재식후 1, 2, 4, 6, 8 및 12일이 경과된 후 심장관혈을 통하여 쥐를 희생시킨후 3% glutaraldehyde가 포함된 EDTA에서 탈회한후 Epon 포매 하였다. 모든 시편은 유리칼을 사용하여 1미크론 두께로 절편한후 veronal acetate buffer에 녹인 1% toluidine blue로 염색하였다. 파치세포양 세포에 의한 치근흡수는 재식 5-7일후 처음 관찰되었다. 재식 12일후에는 치근 전체에 걸친 광범위한 치근흡수가 관찰되었다. 이상의 결과 ${\beta}$-APN을 포함한 쥐사료 식이요법은 쥐 상악제일대구치의 발치와 재식을 용이하게 하여 일정한 치근흡수를 발현시키는데 많은 도움이 된 것으로 판단되었다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2003.07a
• /
• pp.347-352
• /
• 2003

농산물 포장화물의 경우 농산물의 손상은 겉포장 상자의 파손에 의한 압상이 주요 원인이다. 따라서 농산물 상자의 경우 압축강도를 특히 중요시 여기고 있으며, 한국산업규격을 비롯해 각종 농산물 관련 규정에서는 압축강도에 의한 상자의 품질관리를 규정화 하고 있다. 골판지 상자의 압축강도는 원단인 골판지의 구성 원지들(라이너, 골심지)의 품질과 이들의 구성 형태 및 상자의 외형 치수 비율에 따라 결정되므로, 원지의 링크라쉬(ring crush), 원단의 수직압축강도(edgewise compression strength)를 통해 상자의 압출강도를 관리하는 것이 보통이다. 또한 골판지 상자는 제작 후 유통 과정을 거치면서, 여러 요인에 의해 압축강도가 현격하게 저하되는데, 이중 수분 흡습에 의한 강도저하와 장기 누적하중, 진동 및 충격 등의 피로로 인한 강도 저하가 가장 크다. 여러 산업 분야에서 골판지 상자의 견고성 문제는 물품의 내수 및 수출시 제품에 대한 신뢰성 확보와 기업의 이미지 제고와 직결되는 중요한 사항이다. 특히, 세계 각 국의 농산물 시장이 개방됨에 따라 우리나라 농산물의 수출도 확대될 전망이고 또한 마땅한 대체재가 개발되지 않는 한 골판지 상자의 이용은 날로 증가될 것으로 전망된다. 따라서 골판지 상자의 압축강도와 내구성 향상에 대한 다각적인 연구가 절실하다. (중략)

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2011.07a
• /
• pp.180-183
• /
• 2011

본 논문에서는 HEVC(High Efficiency Video Coding) 부호화기에서 사용되는 TU(Transform Unit) 분할이 깊이에 따라 속도와 화질과 압축률에 미치는 영향을 분석한다. 현재 HD 영상의 표준 부호화기로 사용되던 H.264/AVC 를 대신할 차세대 부호화기인 HEVC 에 대한 표준화 작업이 이루어지고 있으며 이러한 HEVC 부호화기의 특징 중 하나로 영상 압축 시 CU, PU, TU 로 세분화 된 단위를 사용한다는 점을 들 수 있다. HEVC의 reference software 인 HM 의 경우 기존 H.264/AVC 에 비하여 UHD 영상에서 최대 40%에 가까운 비트 절감률을 보이지만 최적화가 이루어지지 않아 실시간 부호화에는 적합하지 않은 속도를 보인다. HM 에서는 각 CU 나 TU 에 대하여 quadtree 형식으로 분할하여 부호화를 수행한 후 최적의 분할 형태를 취하는 방식을 사용하기 때문에 많은 시간을 소요하게 되며 분할되는 깊이에 비례하여 기하급수적으로 속도가 느려지게 된다. 본 논문에서는 TU 가 분할되는 깊이가 부호화 화질과 속도에 어느 정도 영향을 미치는지를 분석하고 화질 손상을 최소화 하는 최적의 TU 분할 깊이를 제안하여 보기로 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.281-284
• /
• 2015

Digital image processing is utilized in various application fields by rapid development of memory cell. However, the noise occurs with various causes in the process of data processing process and various methods have been studied in order to remove such noises. In general, the image is damaged by the mixed noise which has different characteristics each other. This paper proposed a filter algorithm which processes the data according to shape of noise in order to mitigate the impact of the mixed noise added to the image. In addition, this paper compared this filter algorithm with the current methods and used PSNR(peak signal to noise ratio) as a criterion of judgment.