• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.281-293
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• 2020

An anterior cruciate ligament (ACL) reconstruction is one of the most frequent surgical procedures in the knee joint, but despite the better understanding of anatomy and biomechanics, surgical reconstruction procedures still fail to restore rotational stability in 7%-16% of patients. Hence, many studies have attempted to identify the factors for rotational laxity, including the anterolateral ligament (ALL), but still showed controversies. Descriptions of the ALL anatomy are also confused by overlapping nomenclature, but it is usually known as a distinctive fiber running in an anteroinferior and oblique direction from the lateral epicondyle of the femur to the proximal anterolateral tibia, between the fibular head and Gerdy's tubercle. The importance of the ALL as a secondary restraint in the knee has been emphasized for successful ACL reconstructions that can restore rotational stability, but there is still some controversy. Some studies reported that the ALL could be a restraint to the tibial rotation, but not to anterior tibial translation. On the other hand, some studies reported that the role of ALL in rotational stability would be limited as a secondary structure because it bears loads only beyond normal biomechanical motion. The diagnosis of an ALL injury can be performed by a physical examination, radiology examination, and magnetic resonance imaging, but it should be assessed using a multimodal approach. Recently, ALL was considered one of the anterolateral complex structures, as well as the Kaplan fiber in the iliotibial band. Many studies have introduced many indications and treatment options, but there is still some debate. The treatment methods are introduced mainly as ALL reconstructions or lateral extra-articular tenodesis, which can achieve additional benefit to the knee stability. Further studies will be needed on the indications and proper surgical methods of ALL treatment.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.1
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• pp.31-38
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• 2018

Earthquake disasters that exceed the design criteria can pose significant threats to nuclear facilities. Seismic probabilistic safety assessment(PSA) is a probabilistic way to quantify such risks. Accordingly, seismic PSA has been applied to domestic and overseas nuclear power plants, and the safety of nuclear power plants was evaluated and prepared against earthquake hazards. However, there were few examples where seismic PSA was applied in case of a research reactor with a relatively small size compared to nuclear power plants. Therefore, in this study, seismic PSA technique was applied to actually completed research reactor to analyze its safety. Also, based on these results, the optimization study on the seismic capacity of the system constituting the research reactor was carried out. As a result, the possibility of damage to the core caused by the earthquake hazard was quantified in the research reactor and its safety was confirmed. The optimization study showed that the optimal seismic capacity distribution was obtained to ensure maximum safety at a low cost compared with the current design. These results, in the future, can expect to be used as a quantitative indicator to effectively improve the safety of the research reactor with respect to earthquakes.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.523-530
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• 2014

One juvenile raptor which was not able to be identified due to its head damage was discovered on a roadside in Janggok-ri, Jori-eup, Paju on 28th June, 2011. The species was identified by DNA barcoding. After polymerase chain reaction (PCR) of the mitochondrial cytochrome c oxidase subunit I gene (COI), we obtained 695 bp sequences. We analyzed the obtained COI sequence with similar sequences from the BOLD systems and BLAST of the NCBI Genbank, and discovered that its sequence showed 100 % similarity values with the one of the five gray-faced buzzards which were previously researched. In addition, it was confirmed to be a female through sex determination using DNA. Such results are important information as it confirms the breeding of the gray-faced buzzards for the first time in 43 years since its breeding was last recorded in 1968, in Paju. Wildlife rescue center needs to work with adjacent consigned registration and preservation institutions when carcass of wild animals is collected or DNA samples are obtained for more accurate both species and sex identification through a systematic management system in the future. Furthermore, the obtained DNA sample of the gray-faced buzzard and COI gene, DNA barcode, could be used as reference standards for similar researches in the future.

• Conservation Science in Museum
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• v.15
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• pp.122-137
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• 2014

The National Museum of Korea own a historical document box ^K976 that was once used to store Joseon Wangjo Sillok ^{Annals of the Joseon Dynasty} of the Joseon Dynasty. The rectangular box has a lid, and the entire surface is varnished with black lacquer. The wood of the box had become warped and the upper part of the wooden frame had been damaged. In some areas, the paint was flaking off, exposing the underlying wood, and an iron ring that connected the lid to the body of the box was missing. Thus, in 2013, Conservation Science Department in National Museum of Korea began to repair and restore the Joseon document box. Before the treatment, analyses were conducted to examine the box's structure, damaged parts, species of wood, and lacquering techniques. The wood was found to be that of a linden tree. As for the lacquering technique, the surface of the box was first coated with a layer of lacquer and bone ash, and then covered with Korean traditional paper. Next, the box was painted with a layer of mud and ashes, followed by a layer of black pigment mixed with soot, and then varnished again with lacquer.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.6
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• pp.623-629
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• 2002

In transmitting compressed video bit-stream over Internet, packet losses cause error propagations in both spatial and temporal domains, which in turn leads to severe degradation I image quality. In this paper, a new error concealment algorithm, called EBMA(Edge Detection based Boundary Matching Algorithm), is proposed to repair damaged portions of the video frames in the receiver. Conventional BMA(Boundary Matching Algorithm) assumes that the pixels on the boundary of the missing block and its neighboring blocks are very similar, but has no consideration of edges across the boundary. In our approach, the edges are detected across the boundary of the lost or erroneous block. Once the orientation of each edge is found, only the pixel difference along the expected edges across the boundary is measured instead of the calculation of difference along the expected edges across the boundary is measured instead of the calculation of differences between all adjacent pixels on the boundary Therefore, the proposed approach needs very few computations and the experiment shows and improvement of the performance over the conventional BMA in terms of both subjective and objective quality of video sequences.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.67-74
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• 2009

The strength of concrete is one of the most important parameters in evaluating the properties of concrete. Compressive strength of concrete has been widely used because of its convenience of experiments and generality. Compressive strength of concrete varies according to materials and curing conditions. Even with the same materials, the strength varies according to the curing conditions. Therefore, if we want to know the strength of concrete from the construction field, we have to put it in exactly the same curing condition with the construction field. But it is impossible to make the exactly same curing conditions in the laboratory. Also damages occur in order to measure the strength of concrete, because the core hat to be made into the pavement. To overcome these limits, many studies of nondestructive method have already been researched. It was already proven that shear wave velocity was very closely related to the compressive strength. In this study, three different curing temperatures with the same mixture paste were used, and compressive strength and shear wave velocity, according to the aging were measured. The relationship between these two parameters was examined. As results, curing temperature affected the compressive strength and the shear wave velocity, but did not affect the relation between them.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1234-1243
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• 2011

Our study was carried out to develop the severity-adjustment model for length of stay in hospital for community-acquired pneumonia so that we analysed the factors on the variation in length of stay(LOS). The subjects were 5,353 community-acquired pneumonia inpatients of the Korean National Hospital Discharge In-depth Injury Survey data from 2004 through 2006. The data were analyzed using t-test and ANOVA and the severity-adjustment model was developed using data mining technique. There are differences according to gender, age, type of insurance, type of admission, but there is no difference of whether patients died in hospital. After yielding the standardized value of the difference between crude and expected length of stay, we analysed the variation of length of stay for community-acquired pneumonia. There was variation of LOS in regional differences and insurance type, though there was no variation according whether patients receive their care in their residences. The variation of length of stay controlling the case mix or severity of illness can be explained the factors of provider. This supply factors in LOS variations should be more studied for individual practice style or patient management practices and healthcare resources or environment. We expect that the severity-adjustment model using administrative databases should be more adapted in other diseases in practical.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.180-185
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• 2005

Purpose: To purpose of this study is to evaluate the clinical and radiological results of arthroscopic meniscus repair using Rapid Loc device. Materials and Methods: A retrospective study was performed on 44 cases which had been turned out longitudinal tear without degeneration. We repaired all cases with Rapid Loc device. Patients were evaluated using clinical examination, Orthopaedische Arbeitsgemeinschaft Knie (OAK) scheme, and MRI. We regarded patients with joint line tenderness, swelling or McMurray positive test as clinical failure. Results: A mean age was 33.3 years and follow-up period was average 15 months. Clinical results were excellent 15 cases(34.1%), good 20 cases(45.5%), fair 7 cases(15.9%), poor 2 cases(4.5%). MRI showed grade 115 cases(33.3%), grade II 22 cases(50%), grade III 7 cases(16.7%). Clinical failures were 8 cases and only one complication was developed. Conclusion: Rapid Loc device showed the excellent results in meniscus repair. We regard it has a lot of advantages in safety, softness, ease, ability to control tension at repair site.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.259-266
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• 2010

The study focuses on the value of Micro CT, a high resolution X-ray imaging device, by using it on rats to observe the overall portal vein image of the liver and the microvasculature of each lobes, visualize the 4 segmental lobes and acquire 3D image of the microvasculature through the reconstruction of sectional image data. Less of the damage to liver of the 5 mice, the device was able to separate the liver into 4 segmental lobes and displayed the 4 portal vein microvasculature in 2D. By using the 3D MIP technique, observation of the whole portal vein system microvasculature in 3D image was made possible along with each of the portal vein segment's branches until the 6th branch. Measured the size of 6branch, the average was measured at 1branch : $0.51mm{\pm}0.08$, 2 branch : $0.32mm{\pm}0.12$, 3 branch : $0.23mm{\pm}0.11$, 4 branch : $0.19mm{\pm}0.08$, 5 branch : $0.13mm{\pm}0.06$, 6 branch : $70.5{\mu}m{\pm}14.1$. The 3D image and the images of the microvasculatures in the result of study proved that the Micro-CT can be considered many useful device in obtaining high resolution images.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4A
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• pp.331-340
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• 2011

The application of newly developed fiber-sheet and steel-plate composite plate (FSP) as a means of improving strength and ductility capacity of concrete cylinders under axial compression load through confinement is investigated experimentally in this study. An experimental investigation involves axial load tests of two types of FSP strengthening material, two anchoring methods, and three concrete strengths. The FSP-confined cylinder tests showed that FSP provided a substantial gain in compressive strength and deformability. The performance of FRP-confined cylinders was influenced by type of the FSP strengthening material, the anchoring method, and concrete compressive strength. The FSP failure strains obtained from FSP-confined cylinder tests were higher than those from FRP-confined cylinder tests. The magnitude of FSP failure strain was related to the FSP composite effectiveness. The effects of FSP confinement on the concrete microstructure were examined by evaluating the internal concrete damage using axial, radial, and volumetric strains. From the observations obtained in this investigation, it is believed that FSP is one of the best solutions for the confinement of concrete compressive members.