• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4628-4636
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• 2023

Cables are indispensable in nuclear power plants for transmitting data measured by various types of detectors, such as self-powered neutron detectors (SPNDs). These cables will generate disturbing signals that must be accurately distinguished and eliminated. Given that the cable current is not very significant, previous research has focused on SPND, with little attention paid to cable evaluation and validation. This paper specifically focuses on the quantitative analysis of cables and proposes a theoretical model to predict cable noise. In this model, the reaction characteristics between irradiated neutrons and cables were discussed thoroughly. Based on the Monte Carlo method, a comprehensive simulation approach of neutron sensitivity was introduced and long-term irradiation experiments in a heavy water reactor (HWR) were designed to verify this model. The theoretical results of this method agree quite well with the experimental measurements, proving that the model is reliable and exhibits excellent accuracy. The experimental data also show that the cable current accounts for approximately 0.2% of the total current at the initial moment, but as the detector gradually depletes, it will contribute more than 2%, making it a non-negligible proportion of the total signal current.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1035-1043
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• 2019

The object of is this research is to find out the optimal Tesla by evaluating SNR and CNR, after testing 1.5 T and 3.0 T. The randomly selected patients tested by nasopharynx MRI transmitted in PACS were applied to the research. Two MRI units(1.5 T, 3.0 T) was used for analyzing the data. As a method of analysis, in T1W highlighting and T1 fat removal images, we set up a certain area of interest and evaluated the SNR and CNR on tongue, spinal cord, masseter muscle, fat, parotid gland, and tumor tissue. We evaluated the SNR and CNR by quantitative analysis of six tissue, measuring the quality of images for uniform fat removal, magnetic sensitivity artifact on a four-point scale by qualitative analysis. The statistical significance of this date analysis was based on independent sample verification and was accepted when the P value was less than 0.05. As a result of analysis of both devices, 3.0 T was high in the quantitative evaluation, while 1.5 T was high in the qualitative evaluation. Considering the advantages and disadvantages of each device, and if the device is selected complementarily and applied to patients, it is believed that it will provide the optimal information.

• Journal of Korea Foundry Society
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• v.41 no.5
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• pp.419-433
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• 2021

Al-Si-Cu alloys benefit from the addition of copper for better hardness and strength through precipitation hardening, which results in remarkably strong alloys. However, the addition of copper expands the solidification range of Al-Si-Cu alloys, and due to this, these alloys become more prone to hot tearing, which is one of the most common and serious fracture phenomena encountered during solidification. The conventional evaluation method of the hot tearing properties of an alloy is a relative and qualitative analysis approach that does not provide quantitative data about this phenomenon. In the present study, the mold itself part of a device developed in Instone et al. was partially modified to obtain more reliable quantitative data pertaining to the hot tearing properties of an Al-Si-Cu casting alloy. To assess the influence of Cu element, four levels of Cu contents were tested (0.5, 1.0, 3.0, and 5.0 wt.%) in the Al-Si-Cu system alloy and the hot tearing properties were evaluated in each case. As the Cu content was increased, the hot tearing strength decreased to 2.26, 1.53, 1.18, and 1.04 MPa, respectively. At the moment hot tearing occurred, the corresponding solid fraction and solidification rate decreased at the same temperature due to the increase in the solid-liquid coexistence range as the Cu content increased. The morphology of the fracture surfaces was changed from dendrites to dendrites covered with residual liquid, and CuAl₂ phases were observed in the vicinity of hot tearing.

• Journal of Korea Multimedia Society
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• v.17 no.9
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• pp.1115-1124
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• 2014

The objective of this study is to present a new design method at the idea brainstorming process, which requires a great deal of time and effort to seek their own ideas in existing design process and to develop a user support idea forms generation system called OCIGS (Openware Creative Idea Generation System) that makes it possible to create a variety and 3D forms as well as a quantitative evaluation data for the actual types that compose the aesthetic factors and designs of qualitative standards. In order to achieve these objectives : First, overcoming the limitation of 3D form generation ability by establishing visual application system, Second, accepting users' opinions by generating 3D images dynamically, analysing and giving information on the preferred ones on the web on real time, Third, identifying tendency of preference so that they can generate preferred colors and images in future by updating image combination and dropping low-preferred ones. This system would play a role as an idea or form generation application in the actual 3d form design development process.

• Journal of the Korean Institute of Educational Facilities
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• v.19 no.1
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• pp.37-44
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• 2012

This study developed an algorithm to predict the most efficient evacuation protocol in an elementary school that has an irregular type of architectural planning. The assumption of this study takes a stand point that today's elementary schools are designed in unusual and irregular floor type and, therefore, past architect's knowledge regarding efficient evacuation will no longer effective to save lives. In this regard, this study applied an algorithm that is especially designed to find appropriate locations in general in the field of industrial engineering, which has been proven for many decades. Furthermore, this study not only adapted an engineering model but also conversed to examine spatial relationship and added the concept of group evacuation, which will delay the whole evacuation process, in the tested algorithm to make it more architectural. Consequently, this study compared its outcome with an existing elementary school and questioned its effectiveness in evacuation process based on the algorithm.

• Annual Conference on Human and Language Technology
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• 2017.10a
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• pp.298-300
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• 2017

본 논문에서는 단순하지만 효과적인 단어 표현 방법인 Bags of Features에 대한 비교 실험을 수행한다. Bags of Features는 어휘집의 크기에 제한이 없으며, 문자 단위의 정보를 반영하고, 벡터화 과정에서 신경망 구조에 의존하지 않는 단어 표현 방법이다. 영어 품사 부착 실험을 사용하여 실험한 결과, one-hot 인코딩을 사용한 모델과 대비하여 학습 데이터에 존재하지 않는 단어의 경우 49.68%, 전체 부착 정확도는 0.96% 향상이 관찰되었다. 또한, Bags of Features를 사용한 모델은 기존의 영어 품사 부착 분야의 최첨단 모델들 중 학습 데이터 외의 추가적인 데이터를 활용하지 않는 모델들과 비견할 만한 성능을 보였다.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.1
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• pp.55-64
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• 2004

Conventional bipolar surface electromyography(EMG) technique detects only the superimposed electromyographic activity of a large number of motor units due to its low spatial resolution. For the diagnosis of neuromuscular disorder, the information of single MU is required. In this paper, 9 channel array surface electrode system was as designed and MLoG filter was proposed. Also the MCPT(modified convolution processing technique)method was proposed for the improvement of MUAP resolution. For performance evaluation, power spectrum analysis of random data and raw EMG signal comparison of MUAP shape and quantitative estimation of SNR were executed. As a result, the MUAP resolution improvement of 32％ was obtained from the standpoint of the signal-to-noise ratio(SNR).

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.1-11
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• 2001

Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes alter therapy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.201-205
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• 2005

This work presents a study on development of a practical and quantitative technique for assessment of the structural health condition by piezoelectric Impedance-based technique associated with longitudinal wave propagaation. The natural frequency of the object has a tendency of frequency shifting according to hole size corresponded to real structure crack and crack size. In order to estimate the damage condition numerically, we suggest the evaluation method of Impedance peak frequency shift hF in this paper.

• Natural Product Sciences
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• v.17 no.1
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• pp.51-57
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• 2011

The seeds of Abrus precatorius L. (Family- Fabaceae) constitute the drugs Abrus, Gunja, or Ratti in commerce. In the Indian System of Medicine, the seeds are used for sciatica, paralysis, headache, dysentery, diarrhoea, leprosy, ulcer, nervous disorders, alopecia, as well as anti-inflammatory, antidiabetic, antibacterial, antitumor, sexual stimulant and abortifacient. Seeds are poisonous and therefore are used after mitigation. The protein abrin is responsible for the highly toxic properties of seeds. Quantitative HPTLC analysis of the methanolic extract of seeds determined the presence of 0.4018% gallic acid and 0.4009% glycyrrhizin. The present study was undertaken to develop an HPTLC method, as well as ascertain the physico-chemical, morphological and histological parameters to establish the authenticity of A. precatorius seeds.