• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.522-526
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• 2007

Structural features and electrochemical performances of cokes pyrolized from oxidized cokes were examined, and compared with KOH-activated coke. Needle cokes ($d_{002}=3.5{\AA} $), having a graphene layer structure, were changed to a single phase of graphite oxide after oxidation treatment with an acidic solution having an $NaCLO_3$/needle coke composition ratio of above 7.5, and the inter-layer distance of the oxidized coke was expanded to $6.9{\AA} $ with increasing oxygen content. After heating at $200^{\circ}C$, the oxidized coke was pyrolized to the graphene layer structure with inter-layer distance of $3.6{\AA} $. However, the change of the inter-layer distance of the needle coke was not observed in the KOH activation process. On the other hand, an intercalation of electrolyte ions into the pyrolized coke, observed at first charge, occurred at 1.0 V, in which the value was lower than that of KOH-activation coke. The cell capacitor using pyrolized coke exhibited a lower internal resistance of $0.57{\Omega}$ in 1 kHz, and a larger capacitance per weight and volume of 30.3 F/g and 26.9 F/ml at the two-electrode system in the potential range 0~2.5 V than those of the cell capacitor using KOH-activation of coke. This better electrochemical performance may be associated with structure defects in the graphene layer derived from the process of the inter-layer expansion and shrinkage.

• Journal of Veterinary Clinics
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• v.31 no.5
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• pp.425-429
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• 2014

Two dogs were presented with a history of anorexia, respiratory distress, or epistaxis. On physical examination, the dogs showed difficulty breathing and open-mouth breathing and large masses were found on the hard palate and soft palate. Cardiac arrest happened in case 2 and the dog was stabilized with cardiopulmonary resuscitation and oxygen therapy. Computed tomography demonstrated that the mass occupied the oropharynx, intrapharyngeal ostium, and laryngopharynx including the hard palate and soft palate in case 1. Palliative surgery was decided to improve swallowing and breathing with owner's consent in two dogs. Buccal mucosal flaps were performed for reconstruction of defects using rotational and single-pedicle advancement flaps and bilateral 90 degree transposition flaps in cases 1 and 2, respectively. Histopathology results described the oral masses as amelanotic melanoma in two dogs. The owners reported that there was normal swallowing and breathing at 7 days postoperatively in two dogs. In case 1, recurrent tumor was identified caudal to the hard palate 4 weeks after surgery. The owner did not allow further treatment and the dog became lost to follow-up at 2 months postoperatively. In case 2, there was no clinical or radiographic evidence of a local recurrence or distant metastasis at 3 weeks after surgery. The owner informed that the dog died suddenly with no signs of anything particularly wrong at 7 weeks after surgery.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.271-298
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• 1998

During these days of new understanding, western medicine has developed remarkably and a revaluation of traditional medicine has been achieved. This appears to have resulted from the sound criticisms of what western medicine has achieved up to now; excessive subdivisions of clinical medicine, severe toxicity of chemical drugs, lack of understanding about patients complaints which cannot be understood objectively, and etc. It is thought that the role of traditional medicine will be more important in the future than it is now. Someone said that the research methods of traditional medicine depends on the way of experimental science too much. That there was no consideration of a system for traditional medicine and the critic also went so far as to assert that in some cases the characteristics of eastern ideas is to permit irrationalism itself. In view of this thinking, the term traditional medicine seems to have been used somewhat too vaguely. However, traditional medicine is a medical treatment which has existed since before the appearance of modern medicine and it was formed from a traditional culture with a long history. One form of traditional medicine, oriental medicine based upon ancient Chinese medicine, was received in such countries as Korea, Japan, Thailand, Vietnam, Tibet, and Mongolia. Oriental medicine then developed in accordance with its own environment, race, national characteristics, and history. Although there are some simultaneous differences between them, three nations in Eastern Asia; Korea, Japan, and China, have especially similar features in their clinical prescriptions and medical literature. These three nations are trying to understand each others unique traditional medicines through numerous exchanges. Even though many differences in their ways of studying have developed over history exist, recent academic discussions have been made to explore new ways into oriental medicine. Therefore a comparative study of oriental medicine has gradually been thought to be more important. In Korea the formation of a new future-oriented paradigm for oriental medicine is being demanded. The purpose of the new paradigm is to create a new recognition of traditional culture which creates an understanding of oriental medicine to replace the diminished understanding of oriental medicine that was brought about by the self-denial of traditional culture in modem history and cultural collisions between oriental and occidental points of view. Therefore, to make a new paradigm for oriental medicine which is suitable for these days, and fortifies the merit of oriental medicine while compensating its defects, the author has compared the characteristics of oriental medicines in Korea, Japan, and China. The conclusions of this research are as follows: 1. The fundamental differences of the traditional medicines of these three nations are caused by the differences in the systems of Naekyung and Sanghannon. 2. The pattern-identification of illnesses is generally divided into two categories; the pattern identification of Zang-Fu and the pattern identification of prescription. 3. There are many differences in the definition of terms, such as Yin and Yang, Deficiency and Excess, and etc. 4. Chinese traditional medicine has some new concepts about pattern identification and epidemic febrile disease. 5. Japanese traditional medicine has some characteristics about pattern identification of the whole bodys condition and signs of abdominal palpation. 6. In terms of the effects of herbal drugs, Chinese traditional medicine attaches great importance to the experiential efficacy of the herb, and Japanese traditional medicine is taking a serious view of the effects of experimental medical actions.

• Korean Journal of Materials Research
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• v.10 no.4
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• pp.312-316
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• 2000

A study has been made to investigate the effects of hot isostatic pressing(HIP ping) on bond strength and elevated temperature characteristics of thermal barrier coating(TBC). The specimens were prepared by HIPping of TBC which is composed of the ceramic top coat(8wt%$Y_2$$O_3$-$ZrO_2$) and the metallic bond coat on the matrix of IN738LC superalloy. The results showed that the porosity and microcracks in the ceramic top coat of TBC were significantly decreased by HIP. As a result, the bond strength of the HIPped coating was increased above 48% compared to that of as-coated specimen and microstructure was homogenized. It was found that the thermal cycle resistance of HIPped coating was inferior to that of as-coated specimen. It was considered that this result was mainly caused by the reduction of internal defects in the top coat layer which could play a role in relaxing the thermal stress due to a large difference in thermal expansion between TBC and matrix.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.133-139
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• 2012

For the examination of nuclear medicine, myocardial scan is a good method to evaluate a hemodynamic importance of coronary heart disease. but, the automatized qualitative measurement is additionally necessary to improve the decoding efficiency. we suggests the creation of cardiac three-dimensional model and model of three-dimensional cardiac thickness as a new measurement. For the experiment, cardiac reduced cross section was obtained from SPECT. Next, the pre-process was performed and image segmentation was fulfilled by level set. for the modeling of left cardiac thickness, it was realized by applying difference equation of two-dimensional laplace equation. As the result of experiment, it was successful to measure internal wall and external wall and three-dimensional modeling was realized by coordinate. and, with laplace formula, it was successful to develop the thickness of cardiac wall. through the three-dimensional model, defects were observed easily and position of lesion was grasped rapidly by the revolution of model. The model which was developed as the support index of decoding will provide decoding information to doctor additionally and reduce the rate of false diagnosis as well as play a great role for diagnosing IHD early.

• Journal of Korea Water Resources Association
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• v.54 no.spc1
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• pp.1071-1081
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• 2021

In addition to the current quality control procedures for the weather observation performed by the Korea Meteorological Administration (KMA), this study proposes quality inspection standards for Internet of Things (IoT) urban weather observed data based on machine learning that can be used in smart cities of the future. To this end, in order to confirm whether the standards currently set based on ASOS (Automated Synoptic Observing System) and AWS (Automatic Weather System) are suitable for urban weather, usability was verified based on SKT AWS data installed in Seoul, and a machine learning-based quality control algorithm was finally proposed in consideration of the IoT's own data's features. As for the quality control algorithm, missing value test, value pattern test, sufficient data test, statistical range abnormality test, time value abnormality test, spatial value abnormality test were performed first. After that, physical limit test, stage test, climate range test, and internal consistency test, which are QC for suggested by the KMA, were performed. To verify the proposed algorithm, it was applied to the actual IoT urban weather observed data to the weather station located in Songdo, Incheon. Through this, it is possible to identify defects that IoT devices can have that could not be identified by the existing KMA's QC and a quality control algorithm for IoT weather observation devices to be installed in smart cities of future is proposed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.649-656
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• 2019

Flux cored arc welding (FCAW), which is used widely in many fields, such as shipyards, bridge structures, construction machinery, and plant industry, is an alternative to shielded metal arc welding (SMAW). FCAW is used largely in the welding of carbon and alloy steel because it can be welded in all poses and obtain excellent quality in the field under a range of working conditions. In this study, the mechanical properties of welded parts were analyzed after different welding of SS400 and SM490A using FCAW. The following conclusions were drawn. The tensile test results satisfied the KS standard tensile strength in the range of 400~510 N/mm2 in all welding positions. The bending test confirmed that most of the specimens did not show surface breakage or other defects during bending and exhibited sufficient toughness, even after plastic deformation. The hardness test results were lower than the standard value of 350 Hv of KS B 0893. Similar to the hardness test, were greater than the KS reference value. The macro test revealed no internal flaws, non-metallic inclusions, bubbles or impurities on the entire cross section of the weld, and there were no concerns regarding lamination.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.134-141
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• 2019

This paper is a study on design improvement of rotorcraft horizontal stabilizer. The rotorcraft horizontal stabilizer stabilizes the behavior of the pitch, yaw, etc. from the aircraft. Because of this role, horizontal stabilizers are a major component (Flight Safety Part) that affects flight safety on rotorcraft. However, when the rotorcraft was operated in domestic, cracks were found in the inner structure of the horizontal stabilizer and design improvement was needed. In this paper, we identified the two causes of the horizontal stabilizer crack defects through fracture analysis and structural analysis. The first is the tightening torque when the bolt is tightened, and the second is the lead-lag behavior of aircraft. In order to improve these two causes, bolt fastening method, flange structure and thickness were changed and composite ring was applied. In order to verify the design improvement, the structural analysis was performed and the structural strength was improved. Also Fatigue analysis of the internal structure (Rib 1) was performed and it was confirmed that the requirements were satisfied.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.199-212
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• 2021

The Sebyeonggwan Hall (National Treasure No. 305) is located on the Naval Headquarter of Three Provinces in Tongyeong, and it has partly undergone with several rebuilding, remodeling, repairing and restorations since it's the first establishment in Joseon Dynasty (AD 1605) of ancient Korea. This study focuses on 50 foundation stones that comprise the Sebyeonggwan. These stones are made of six rock types and currently have various shapes of the surface damages. As the foundation stones, the dominant rock type was dacitic lapilli tuffs, and provenance-based interpretation was performed to supply alternative stones for conservation. Most of the provenance rocks for foundation stones showed highly homogeneity with their corresponding stones of petrography, mineralogy and magnetic susceptibility. According to surface deterioration assessments, the most serious damages of the stones were blistering and scaling. The deterioration mechanism was identified through the analysis of inorganic contaminants, and the primary reason is considered salt weathering caused by sea breeze and other combined circumstances. Based on the mechanical durability of the stones, there was no foundation stone that required the replacement of its members attributed to the degradation of the rock properties, but conservation treatment is considered necessary to delay superficial damage. The foundation stones are characterized by a combined outcome of multiple petrological factors that caused physical damage to surfaces and internal defects. Therefore, it's required to diagnosis and monitoring the Sebyeonggwan regularly for long-term preservation.

• Journal of the Korean Society of Radiology
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• v.16 no.4
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• pp.381-386
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• 2022

Non-Destruction Test (NDT) is a method to check internal defects without destroying the product. Among them, radiographic testing (RT) uses high-energy radiation, so it is very important to prevent radiation exposure of workers. Therefore, in this study, in this study, a radiation sensor structure that improves radiation detection performance compared to the existing PbI₂ and can immediately detect accidents in RT was presented. For evaluation, the conversion efficiency was analyzed in the gamma ray source through FLUKA simulation. PbI₂ with overlapping Gd₂O₂S:Tb presented in this study showed a higher radiation sensitivity from 1.22 to 3.22 times than that of non-overlapping PbI₂. This indicates that the presented sensor is suitable for use as a radiation sensor for source detection in RT.