• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.1
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• pp.43-63
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• 2022

The aim of this review is to communicate some essential knowledge of the underlying mechanism of the corrosion of structural containment alloys during molten salt reactor operation in the context of prospective online monitoring in future MSR installations. The formation of metal halide species and the progression of their concentration in the molten salt do reflect containment corrosion, tracing the depletion of alloying metals at the alloy salt interface will assure safe conditions during reactor operation. Even though the progress of alloying metal halides concentrations in the molten salt do strongly understate actual corrosion rates, their prospective 1^st order kinetics followed by near-linearly increase is attributed to homogeneous matrix corrosion. The service life of the structural containment alloy is derived from homogeneous matrix corrosion and near-surface void formation but less so from intergranular cracking (IGC) and pitting corrosion. Online monitoring of corrosion species is of particular interest for molten chloride systems since besides the expected formation of chromium chloride species CrCl₂ and CrCl₃, other metal chloride species such as FeCl₂, FeCl₃, MoCl₂, MnCl₂ and NiCl₂ will form, depending on the selected structural alloy. The metal chloride concentrations should follow, after an incubation period of about 10,000 hours, a linear projection with a positive slope and a steady increase of < 1 ppm per day. During the incubation period, metal concentration show 1^st order kinetics and increasing linearly with time^1/2. Ideally, a linear increase reflects homogeneous matrix corrosion, while a sharp increase in the metal chloride concentration could set a warning flag for potential material failure within the projected service life, e.g. as result of intergranular cracking or pitting corrosion. Continuous monitoring of metal chloride concentrations can therefore provide direct information about the mechanism of the ongoing corrosion scenario and offer valuable information for a timely warning of prospective material failure.

• Computers and Concrete
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• v.29 no.6
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• pp.393-405
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• 2022

Lightweight concrete is a superior material due to its light weight and high strength. There however remain significant lacunae in engineering knowledge with regards to shear failure of lightweight fiber reinforced concrete beams. The main aim of the present study is to investigate the optimum usage of steel fibers in lightweight fiber reinforced concrete (LWFRC). Multi-scale finite element model calibrated with experimental results is developed to study the effect of steel fibers on the mechanical properties of LWFRC beams. To decrease the amount of steel fibers, it is preferred to reinforce only the middle section of the LWFRC beams, where the flexural stresses are higher. For numerical simulation, a multi-scale finite element model was developed. The cement matrix was modeled as homogeneous and uniform material and both steel fibers and lightweight coarse aggregates were randomly distributed within the matrix. Considering more realistic assumptions, the bonding between fibers and cement matrix was considered with the Cohesive Zone Model (CZM) and its parameters were determined using the model update method. Furthermore, conformity of Load-Crack Mouth Opening Displacement (CMOD) curves obtained from numerical modeling and experimental test results of notched beams under center-point loading tests were investigated. Validating the finite element model results with experimental tests, the effects of fibers' volume fraction, and the length of the reinforced middle section, on flexural and residual strengths of LWFRC, were studied. Results indicate that using steel fibers in a specified length of the concrete beam with high flexural stresses, and considerable savings can be achieved in using steel fibers. Reducing the length of the reinforced middle section from 50 to 30 cm in specimens containing 10 kg/m3 of steel fibers, resulting in a considerable decrease of the used steel fibers by four times, whereas only a 7% reduction in bearing capacity was observed. Therefore, determining an appropriate length of the reinforced middle section is an essential parameter in reducing fibers, usage leading to more affordable construction costs.

• Journal of Korean Medicine for Obesity Research
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• v.18 no.2
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• pp.128-143
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• 2018

Objectives: The purpose of this study is to investigate the efficacy and the mechanisms of dietary supplements in cellulite treatment, and then to provide the theoretical and clinical basis for the cellulite treatment in Korean Medicine. Methods: We searched for articles from Korea, China, and English electronic database (Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], KMbase, Research Information Sharing Service [RISS], Oriental Medicine Advanced Searching Integrated System [OASIS], National Assembly Library, Korean Traditional Knowledge Portal, Google scholar, PubMed, Scopus, China National Knowledge Infrastructure [CNKI]) until April 2018. We chose clinical trial studies by inclusion criteria through titles, abstracts and articles. Results: A total of 10 studies were selected through search. The experimental group had shown more effective cellulite improvement in 90% of studies. Also, improvement of symptoms related with cellulite like pain, edema, heaviness and increase of skin surface temperature were observed in experimental group. In addition, the density of connective tissues of the dermal layer was increased in experimental group. Conclusions: The use of dietary supplements in cellulite treatment is thought to be effective through mechanisms that antioxidant efficacy, microcirculation improvement, interstitial matrix improvement, diuretic effect, and skin metabolic activity effect.

• Biomolecules & Therapeutics
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• v.20 no.4
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• pp.357-370
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• 2012

Radiation therapy, the most commonly used for the treatment of brain tumors, has been shown to be of major significance in tumor control and survival rate of brain tumor patients. About 200,000 patients with brain tumor are treated with either partial large field or whole brain radiation every year in the United States. The use of radiation therapy for treatment of brain tumors, however, may lead to devastating functional deficits in brain several months to years after treatment. In particular, whole brain radiation therapy results in a significant reduction in learning and memory in brain tumor patients as long-term consequences of treatment. Although a number of in vitro and in vivo studies have demonstrated the pathogenesis of radiation-mediated brain injury, the cellular and molecular mechanisms by which radiation induces damage to normal tissue in brain remain largely unknown. Therefore, this review focuses on the pathophysiological mechanisms of whole brain radiation-induced cognitive impairment and the identification of novel therapeutic targets. Specifically, we review the current knowledge about the effects of whole brain radiation on pro-oxidative and pro-inflammatory pathways, matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) system and extracellular matrix (ECM), and physiological angiogenesis in brain. These studies may provide a foundation for defining a new cellular and molecular basis related to the etiology of cognitive impairment that occurs among patients in response to whole brain radiation therapy. It may also lead to new opportunities for therapeutic interventions for brain tumor patients who are undergoing whole brain radiation therapy.

• Journal of the Korea Society of Computer and Information
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• v.24 no.9
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• pp.135-142
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• 2019

Given the ability and skills required by modern people, marketing can be divided into knowledge-related skill such as marketing plans, market segmentation, and marketing mix management and supportive skill such as communication, inter-organizational management, creativity, and decision making. Knowledge related skills can be nurtured in existing marketing classes, but it is recognized that special educational programs such as self marketing are needed to develop and train supportive skills regardless of education levels or major education. This paper is aimed to design for marketing educational program for the self marketing. In this study, a DACUM method job analysis to extract contents by specialists such as model setting of task and job, job statement, job analysis, education course development, and so on. In the first place, this report presents job analysis model by procedures for developing selection criteria of examination questions of the self marketing qualification. The first step is preparation for job analysis, the second step: the establishment of job models, the third step : the job specification and task analysis, the fourth step: the review of job model, the fifth step: the establishment of subjects for examination matrix table for making questions.

• Communications of Mathematical Education
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• v.37 no.3
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• pp.443-465
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• 2023

This study examines the content of vectors and matrices in Artificial Intelligence Mathematics textbooks (AIMTs) from the 2015 revised mathematics curriculum. We analyzed the implementation of foundational mathematical concepts, specifically definitions and related sub-concepts of vectors and matrices, in these textbooks, given their importance for understanding AI. The findings reveal significant variations in the presentation of vector-related concepts, definitions, sub-concepts, and levels of contextual information and descriptions such as vector size, distance between vectors, and mathematical interpretation. While there are few discrepancies in the presentation of fundamental matrix concepts, differences emerge in the subtypes of matrices used and the matrix operations applied in image data processing across textbooks. There is also variation in how textbooks emphasize the interconnectedness of mathematics for explaining vector-related concepts versus the textbooks place more emphasis on AI-related knowledge than on mathematical concepts and principles. The implications for future curriculum development and textbook design are discussed, providing insights into improving AI mathematics education.

• Journal of Korea Technology Innovation Society
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• v.10 no.4
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• pp.687-705
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• 2007

Nowadays it is more important to measure the technological impact of a concerned R&D technology on others, when deciding or selecting strategically, under the environment such as more complex, more uncertain and more costly. But there was very few of proper methods to measure quantitatively. So we studied on measuring the technological impact of one group of technologies on others, which means the flow of disembodied knowledge, using patent citation analysis. We reviewed the prior art of the measurement of technological impact, and designs the effective citation analysis method using patent information, analyzing the prior art of patent citation analysis method and ie index. Finally, we developed the disembodied knowledge flow matrix between technology groups, counting citation frequencies between them, using KISTI's US patent database(USPA) and the index to represent the technological impact to others using the developed matrix as well as the intrinsic nature of the technological groups clustering by network analysis. The results of this study is to present the insight of a technological impact on the others quantitatively and this study aims at using them to refer to R&D budgeting and decision making in case of R&D planning or to the basic information to understand technology conversion or fusion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.153-163
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• 2018

There is insufficient effective management systems to achieve project goalsin disaster and safety R&D. Therefore, to develop an R&D performance management system, this paper develops a R&D performance management matrix based on PMBOK to systematize a process and to enhance efficiency of performance management. Also, this paper identified vulnerable procedures in disaster management by analyzing related laws, work process and performance. Analysis results found that the performance management matrix in disaster management R&D consists of 5 process groups, 7 knowledge areas and 47 processes. Also, the performance of the diffusion knowledge process was evaluated as weak in the present management system. This study defined ITO and developed a data flow diagram for applicationto related work. The suggestions of this study include the related work to enhance R&D performance, contribute to improving diffusion of R&D performance, and enhance the utilization of developed technologies.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.1
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• pp.1-8
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• 2005

Image morphing to generate 2D transitions between images may be difficult even to express simple 3D transformations. In addition, previous view morphing method requires control points for postwarping, and is much affected by self- occlusion. This paper presents a new morphing algorithm that can generate automatically in-between scenes from un-calibrated images. Our algorithm rectifies input images based on the fundamental matrix, which is followed by linear interpolation with bilinear disparity map. In final, we generate in-between views by inverse mapping of homography between the rectified images. The proposed method nay be applied to photographs and drawings, because neither knowledge of 3D shape nor camera calibration, which is complex process generally, is required. The generated in-between views can be used in various application areas such as simulation system of virtual environment and image communication.

• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.527-537
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• 1998

This article is a part of a research on the elementary science curriculum development to enhance creative problem-solving abilities. The components of the curriculum have been identified as 'scientific knowledge', 'process skills' & 'divergent/critical thinking'. Among these components, construction of the scientific knowledge that enables creative problem-solving abilities has been selected as an intensive research topic for the purpose of the present research. To avoid or to prevent the knowledge learned from separate facts and concepts, five themes have been selected so as to incorporate with all three areas of the elementary science curriculum, i.e., physical science, earth science and life science. The five themes are, 'structure', 'change', 'interaction', 'energy' and 'stability'. The contents of elementary science, which have been selected from the 3rd, 6th and 7th National Elementary Science curriculum, were reconstructed based on the five themes given above. The results of reconstruction are presented in the form of matrix, such that the vertical axis represents how the concepts are related within each domain of science, while the horizontal axis shows how the concepts are interconnected between domains of science. Therefore, based upon the five themes, individual or separate knowledge can be put into more unified knowledge so that contribution of knowledge transfer to new ones can be expected for leaners who will be creative in problem-solving. The process and products of the curriculum development as well as the background of the present research are described and discussed in detail.