• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.115.2-115.2
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• 2016

Al alloys are being used widely for automobile, aerospace and mechanical components because of their high strength ratio to weight. However, still they suffer from abrasion or corrosion owing to insufficient resistances to friction or mechanical impact and chemical attack. Plasma electrolytic oxidation (PEO) method is one of the promising surface treatment methods for Al alloys which can render better hardness than aluminum anodic oxide (AAO) films prepared by conventional anodizing method in acidic solutions. In this presentation, some basic nature of PEO film formation and growth process on Al alloys will be presented based on the experimental results obtained and discussed in view of dielectric breakdown and reformation and the role of various anions in film breakdown and reformation of PEO films.

• Korean Journal of Poultry Science
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• v.26 no.2
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• pp.131-144
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• 1999

Coccidiosis, an intestinal infection caused by intracellular protozoan parasites belonging to several different species of Eimeria seriously impairs the growth and feed utilization of livestock and poultry. Due to complex life cycle of organism and intricate host immune responses to Elmeria, coccidia vaccine development has been difficult. Understanding of basic imunobiology of pertinent host-parasite interactions is necessary for the development of novel control strategy. Although chickens infected with Eimeria spp. produce parasite-specific antibodies in both the circulation and mucosal secretions, antibody mediated responses play a minor role in protection gainst coccidiosis. Rather, increasing evidence show that cell-mediated immunity plays a major role in resistance to coccidiosis. T-lymphocytes appear to respond to coccidiosis both through cytokine production and a direct cytotoxic attack on infected cells. The exact mechanisms by which T-cells eliminate the parasites, however, remain to be investigated. Since it is crucial to understand the intestinal immune system in order to develop an immunological control strategy against any intestinal immune system in order to develop an immunological control strategy against any intestinal diseases, this presentation will summarize our current understanding of the avian intestinal immune system and mucosal immune responses to Eimeria, to provide a conceptual overview of the complex molecular and cellular events involved in intestinal immune responses to enteric pathogens.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.268-271
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• 2008

If a reactor vessel is failed to retain a molten corium in a postulated severe accident, the molten corium is released outside the reactor vessel into a reactor cavity. The molten corium would attack the concrete wall and basemat of the reactor cavity, which may lead to inevitable concrete decompositions and possible radiological releases. In the OECD/MCCI project, a series of tests were performed to secure the data for cooling the molten corium spread out at the reactor cavity and for the long-term CCI (Core Concrete Interaction). Also, a MCCI (Molten Core Concrete Interaction) analysis code, CORQUENCH was upgraded at Argonne National Laboratory with embedding the new models developed for the tests. This paper deals with analyses of MCCI at plant scale under the conditions of top flooding using the upgraded CORQUENCH code. The modeling approach is briefly summarized first, followed by presentation of a validation calculation that illustrates the predicative capability of the modeling tool. With this background in place, the model is then used to carry out a parametric set of scoping calculations that define approximate coolability envelopes for the LCS (Limestone Common Sand) concrete that has been evaluated in the OECD/MCCI project.

• Journal of Korean Neurosurgical Society
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• v.62 no.2
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• pp.136-143
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• 2019

Moyamoya disease (MMD) is a progressive cerebrovascular disease with unknown etiology, characterized by bilateral steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network formation at the base of the brain. MMD has an intrinsic nature to convert the vascular supply for the brain from internal carotid (IC) system to the external carotid (EC) system, as indicated by Suzuki's angiographic staging. Insufficiency of this 'IC-EC conversion system' could result not only in cerebral ischemia, but also in intracranial hemorrhage from inadequate collateral anastomosis, both of which represent the clinical manifestation of MMD. Surgical revascularization prevents cerebral ischemic attack by improving cerebral blood flow, and recent evidence further suggests that extracranial-intracranial bypass could powerfully reduce the risk of re-bleeding in MMD patients with posterior hemorrhage, who were known to have extremely high re-bleeding risk. Although the exact mechanism underlying the hemorrhagic presentation in MMD is undetermined, most recent angiographic analysis revealed the characteristic angio-architecture related to high re-bleeding risk, such as the extension and dilatation of choroidal collaterals and posterior cerebral artery involvement. We sought to update the current management strategy for hemorrhagic MMD, including the outcome of surgical revascularization for hemorrhagic MMD in our institute. Further investigations will clarify the optimal surgical strategy to prevent hemorrhagic manifestation in patients with MMD.

• Journal of Pharmacopuncture
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• v.23 no.4
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• pp.187-193
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• 2020

Objectives: It was aimed to investigate the basic action mechanism of the autoimmune diseases and common features of all diseases. Autoimmune disease are classified organ specific and systemic. Methods: These diseases are seen systemic and disease start locations, origins seem differently. This makes learning and understanding difficult. Autoimmune diseases investigated for easier understanding. It was noticed that, autoimmune diseases' starting places are specific and same all of them. This remarkable point is very important for acupuncture also. So; whole literatüre was researched and important point was found. Results: Whole autoimmune diseases are attack to mesodermal layers and mesodermal origin organs of the body's. The common property of all these disease are same; Diseases start from the mesoderm and mesodermal layer even though their organ origins' belongs to different germ layer. From this point of view, we were able to classify autoimmune diseases simply and it was planned how can we effect body in this context with acupuncture. Conclusion: And, when immunity comes into question, induction of adaptive immunity is depend on antigen presentation to T cells and this situation take place in the lymph node (LN) and also in the skin.When we sank the acupuncture needle into skin, signals create and start mesodermal contacts, during this time mesenchymal origin' autoimmune cells are regulated with this signals.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.8
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• pp.2230-2252
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• 2024

Advances in deep learning technology have enabled the generation of more realistic deepfakes, which not only endanger individuals' identities but also exploit vulnerabilities in face recognition systems. The majority of existing deepfake detection methods have primarily focused on RGB-based analysis, offering unreliable performance in terms of detection accuracy and time. To address the issue, a grayscale-based deepfake detection method has recently been proposed. This method significantly reduces detection time while providing comparable accuracy to RGB-based methods. However, despite its significant effectiveness, the "key components" that directly affect the performance of grayscale-based deepfake detection have not been systematically analyzed. In this paper, we target three key components: RGB-to-grayscale conversion method, brightness level in grayscale, and resolution level in grayscale. To analyze their impacts on the performance of grayscale-based deepfake detection, we conducted comprehensive evaluations, including component-wise analysis and comparative analysis using real-world datasets. For each key component, we quantitatively analyzed its characteristics' performance and identified differences between them. Moreover, we successfully verified the effectiveness of an optimal combination of the key components by comparing it with existing deepfake detection methods.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.1
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• pp.39-47
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• 2017

Nowadays, there have been an increasing number of illegal use cases where people try to fabricate the working hours by using fake fingerprints. So, the fingerprint liveness detection techniques have been actively studied and widely demanded in various applications. This paper proposes a new method to detect fake fingerprints using CNN (Convolutional Neural Ntworks) based on the patches of fingerprint images. Fingerprint image is divided into small square sized patches and each patch is classified as live, fake, or background by the CNN. Finally, the fingerprint image is classified into either live or fake based on the voting result between the numbers of fake and live patches. The proposed method does not need preprocessing steps such as segmentation because it includes the background class in the patch classification. This method shows promising results of 3.06% average classification errors on LivDet2011, LivDet2013 and LivDet2015 dataset.

• Journal of Life Science
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• v.26 no.11
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• pp.1345-1354
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• 2016

Alopecia areata (AA) is a common and tissue-specific autoimmune disease of hair follicle resulting in the loss of hair on the scalp and elsewhere on the body. Hair follicles is a unique organ because it has its own immune system and hormonal milieu and has a different immune state at each hair cycle stage. The collapses of anagen-dependent hair follicle immune privilege arise autoimmune attack, inducing ectopic MHC class I expression in the hair follicle epithelium and autoantigen presentation to autoreactive CD8+T cells, which results in AA. Clinical and experimental studies have pointed that psychological stress may also influence the hair follicle immune/hormone systems and contribute to the induction of AA. The key pathogenesis of AA is associated with immune privilege guardians (including ACTH, ${\alpha}-MSH$, and $TGF-{\beta}$), natural killer group 2D-positive (NKG2D+) cells (including NK and CD8+T cells), and stress hormones (including CRH and substance P). Effective treatments for AA are still demanded. One of the future targets of treatment will be the modification of hair follicle immune privilege including stress. Recent studies have reported that JAK inhibitors and immunomodulators used in other autoimmune disease, such as psoriasis, atopic dermatitis, and rheumatoid arthritis, Tregs, platelet-rich plasma therapy, statins, and prostaglandin anaolgues are effective for AA. Here the article reviews the recent understanding in the pathogenesis associated with perifollicular endocrine/immunology and new treatments of AA.