• Elastomers and Composites
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• 제53권1호
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• pp.1-5
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• 2018

In the current research, the curing kinetics of a mixture system consisting of a Bisphenol-A type vinyl ester resin and styrene monomer was studied. Methylethylketone peroxide and cobalt octoate were used as the polymerization initiator and accelerator respectively. Thermograms with several different heating rates were obtained using non-isothermal differential scanning calorimetry. Activation energy values analyzed by the Flynn-Wall-Ozawa isoconversional method showed a three-step change with conversion ${\alpha}$: a slight decrease initially for ${\alpha}$ < 0.1, a constant value of 47.9 kJ/mol in the range 0.1 < ${\alpha}$ < 0.7, and a slow increase for 0.7 < ${\alpha}$. When assuming a constant activation energy of 47.9 kJ/mol, an autocatalytic model of the Sestak-Berggren equation was considered as the proper mathematical model of the conversion function, indicating an overall order of 1.2.

• 소성∙가공
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• 제13권8호
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• pp.696-703
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• 2004

The purpose of this study is to examine the bulk/sheet forming characteristics of bulk amorphous alloys in the super cooled liquid state. Recently it is reported that amorphous alloys exhibit stress overshoot/undershoot and non-Newtonian behaviors even in the super cooled liquid state. The stress-strain curves with the temperature-dependences as well as strain-rate dependence of Newtonian/non-Newtonian viscosities of amorphous alloys are obtained based on the previous experimental works. Then, those curves are directly used in the thermo-mechanical finite element analyses. Upsetting and deep drawing of amorphous alloys are simulated to examine the effects of process parameters such as friction coefficient, forming speed and temperature. It could be concluded that the superior formability of an amorphous alloy can be obtained by taking the proper forming conditions.

• Journal of Oral Medicine and Pain
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• 제43권3호
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• pp.92-96
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• 2018

A 39-year-old male presented with severe pain in right posterior mandibular teeth and temporal area. Initially, the pain in the mandibular teeth was moderate, but the concomitant headache was unbearably severe. His medical history was non-contributory. The clinical and radiographic examination failed to reveal any pathology in the region. There was no tenderness to palpation in the temporalis and masseter muscles or temporomandibular joints. The clinical impression was migraine. The pain in the teeth and headache were aborted using ergotamine tartrate and sumatriptan succinate. Atenolol prevented further pain, while amitriptyline and imipramine had no effect. Migraine can present as non-odontogenic pain in the mandibular teeth, although not as frequently as in the maxillary teeth. A correct diagnosis is essential to avoid unnecessary dental treatments and to manage pain effectively. Clinicians should be able to identify migraine with non-odontogenic dental pain and establish a proper diagnosis through a comprehensive evaluation.

• 전자공학회논문지C
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• 제34C권6호
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• pp.44-50
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• 1997

This paper describes the design and test of an on-line non-invasive network performance monitor (hardware portion) for the SPAX parallel computer. The SPAX parallel computer supports up to 256 intel P6 processors with 4 P6 processors constituting a processign node. The nodes are interconnected with a dual two-level crossbar network calle dXcent-net. Since the performance of the SPAX parallel computer is highly dependent on the proper and efficient operation of the network, an on-line non-invasive network performance monitor (with hardware components) has been developed to aid in the monitoring and tunign of the Xcent-net. Successful testing of a prototype node monitor board and PC interface system shows that our monitor design provides a low-cost practical solution to this problem.

• 한국컴퓨터정보학회논문지
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• 제11권3호
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• pp.173-186
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• 2006

본 논문에서는 기존의 비컴포넌트 자바 프로그램을 EJB 컴포넌트 프로그램으로 변환하기 위한 프로세스를 제안한다. 자바 프로그램의 재사용성을 높이기 위해 다음과 같은 방법으로 접근한다. 먼저 기존에 존재하는 비 컴포넌트 자바 프로그램으로부터 컴포넌트 모델에 적합한 구성 요소를 추출하며, 추출된 구성 요소를 중심으로 컴포넌트로 변환하기 위한 기법을 제시한다. 기존 프로그램 코드의 재사용을 극대화하며, EJB의 특성을 고려한 컴포넌트 구성이 가능하도록 클래스 클러스터링과 메소드 단위 중심의 클래스 재구성 방법을 혼합하여 제안한다.

• Annals of Clinical Neurophysiology
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• 제21권2호
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• pp.108-112
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• 2019

Non-Hodgkin's lymphoma (NHL) may initially present with atypical neurological manifestations, including paraneoplastic neurological syndromes. Herein, we report the case showing an initial manifestation of systemic NHL with paraneoplastic demyelination in the brain that initially mimicked the symptoms of stroke, seizure, and brain tumor. A high index of suspicion and timely diagnostic workup is required to prevent diagnostic delay and commence proper management of the condition. In this situation, a whole-body FDG PET/CT could be useful to screen for occult malignancy.

• Earthquakes and Structures
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• 제16권4호
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• pp.401-413
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• 2019

The concept of base isolation for equipment is well known. Its application in buildings and structures is rather challenging. Introduction of horizontal flexibility at the base helps in proper energy dissipation at the base level thus reducing the seismic demand of the super structure to be considered during design. The present study shows the results of a series of numerical simulation studies on seismic responses of secondary system (SS) housed in non-isolated and base-isolated primary structures (PS) including equipment-structure interactions. For this study the primary structure consists of two similar single bay three-store reinforced cement concrete (RCC) Frame building, one non-isolated with conventional foundation and another base isolated with Lead plug bearings (LPB) constructed at IIT Guwahati, while the secondary system is modeled as a steel frame. Time period of the base isolated building is higher than the fixed building. Due to the presence of isolator, Acceleration response is significantly reduced in both (X and Y) direction of Building. It have been found that when compared to fixed base building, the base isolated building gives better performance in high seismic prone areas.

• 산업기술연구
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• 제42권1호
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• pp.13-18
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• 2022

Diabetes mellitus is an abnormally high glucose level in the bloodstream. Several pharmaceuticals are administered to diabetic patients to control their glucose levels. Early diagnosis and proper glycemic management are essential in this situation to prevent further progression and complications. Biosensor-based detection has progressed and shown potential in portable and inexpensive daily assessment of glucose levels because of its simplicity, low cost, and convenient operation without sophisticated instrumentation. This review discusses various systemic aspects of non-invasive glucose monitoring, including materials for monitoring and managing diabetes.

• Communications for Statistical Applications and Methods
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• 제29권2호
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• pp.225-238
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• 2022

In this paper, we propose a clustering method for advanced metering infrastructure (AMI) data in Korea. As AMI data presents non-stationarity, we consider time-dependent frequency domain principal components analysis, which is a proper method for locally stationary time series data. We develop a new clustering method based on time-varying eigenvectors, and our method provides a meaningful result that is different from the clustering results obtained by employing conventional methods, such as K-means and K-centres functional clustering. Simulation study demonstrates the superiority of the proposed approach. We further apply the clustering results to the evaluation of the electricity price system in South Korea, and validate the reform of the progressive electricity tariff system.

• 환경영향평가
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• 제20권5호
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• pp.651-661
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• 2011

The purpose of this study is to estimate the characteristics and pollutant loadings of non-point pollutants that flowed in the streams on precipitation for pollutant loading reduction of Hwa-sung lake inflow streams. Although it has been made an effort to improve the water quality of Hwa-sung basin through the strategies for the preservation of water quality, it is shown that the water quality is not greatly improved. Because it has been industrialized and urbanized near Hwa-sung basin so that it is difficult to reduce the water pollution due to the increase in pollutant loadings of point and non-point sources. In this study, it is investigated the outflow characteristics of non-point pollutants that discharged with storm runoff and estimated the effect of runoff on Hwa-sung basin. The final goal of this study is to utilize the basic information for proper management and strategies of non-point sources on Hwa-sung basin. At the result of inflow streams, Ja-an stream that has the greatest pollutant loadings on precipitation is strongly influenced on the water quantity of Hwa-sung basin. On the other hand, it is shown that Nam-yang stream is strongly influenced on the SS concentration of Hwasung basin among them. Also, all streams; Nam-yang, Ja-ahn, Ah-eun stream; has the degree of slope more than or near 1 in the correlation results so that they have strong pollutant loading impact and the concentration of SS is the highest among other pollutants. So, specific studies on initial rain phenomena are more necessary to manage the pollutants economically. Also, the proper control of SS concentration is required to manage the effluent pollutants effectively on precipitation. So, it is necessary to consider the strategies for non-point pollutants as well as point pollutants when the new management is imposed to reduce the pollutant load for improvement of Hwa-sung basin.