• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4013-4021
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• 2022

A kind of zirconium phosphate mesoporous coordination polymer Zr-EDTMPA was successfully synthesized and characterized using XRD, FTIR, TGA, EA, SEM-EDS, and N₂ sorption-desorption measurements. The prepared Zr-EDTMPA was first employed for the removal of Co(II) from an aqueous solution, and the effects of pH, contact time, temperature, initial Co(II) concentration, reusability, and sorption mechanism were systematically investigated. The results showed that the Zr-EDTMPA is a zirconium phosphate complex formed by the coordination of EDTMPA to Zr in a molar ratio of 1:1. The sorption of Co(II) by Zr-EDTMPA was a pH-dependent, spontaneous and endothermic process, which was better fitted to the pseudo-second-order kinetic model and Langmuir isotherm model. The Zr-EDTMPA was demonstrated to have excellent reusability and presented a high sorption capacity of 73.0 mg·g^-1 for Co(II) at pH 8.0. The sorption mechanism was mainly attributed to the strong coordination between cobalt and the untapped hydroxyl functional groups on Zr-EDTMPA, which was confirmed by XPS spectra. Therefore, as a candidate sorbent with high sorption capacity and excellent reusability, Zr-EDTMPA has a great potential for the removal of Co(II) from aqueous solutions.

• BMB Reports
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• v.42 no.10
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• pp.667-672
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• 2009

Plasma concentrations of adiponectin have been shown to be decreased in patients with obesity, cardiovascular diseases, hypertension and metabolic syndrome. Recent studies have found that adiponectin reduces lipid accumulation in macrophage foam cells which may impact the development of atherosclerosis. However, it remains unclear whether adiponectin is involved in the process of lipid accumulation during myogenesis. Using C2C12 myoblasts, we investigated the effect of adiponectin on intramyocellular lipid accumulation during myogenesis. The results showed that intracellular lipid accumulation is significantly decreased during C2C12 differentiation, apparently due to increased fatty acid oxidation and decreased fatty acid synthesis during this process. C2C12 cells transiently transfected with adiponectin gene showed reduced lipid accumulation as compared to controls. Further experiments demonstrated that adiponectin can suppress lipid accumulation by increasing fatty acid oxidation during C2C12 myogenesis.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.143-146
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• 2006

좁은 국토와 한정된 자원, 주변 국가와의 외래 관광객 유치 경쟁의 심화 등의 이유로 관광산업의 지속적인 발전이 힘들다는 전망이 대두되고 있다. 따라서 날로 다양해지는 관광소비자의 욕구를 정확하게 분석하고, 국내외 관광시장의 흐름을 파악해야 하며, 이러한 관점에서 분석한 결과, 국내 관광지에는 관광객을 유혹할만한 정보를 얻기 힘들고, 이미 통용되고 있는 관광정보 또한 기본적이고 단순한 정보에 지나지 않음을 알 수 있었다. 이에 본 연구는 이야기가 있는 관광지의 정보를 제공하여 보다 흥미 있는 관광정보를 제공하고, 여행자 개개인의 적극적 참여를 유도하기 위해 콘텐츠에 이야기, 애니메이션 및 게임을 제공하고, 주변상점과의 제휴를 통해 상호작용이 가능한 콘텐츠를 개발하였다. 또한 모바일 기기를 기반으로 하여 칼라코드, SMS등의 이용으로 보다 흥미롭고 사용이 편리한 콘텐츠를 개발하고자 노력하였으며, 캐릭터를 개발하여 과학적인 마케팅 전략의 수립으로 지속적인 제주관광발전을 도모하고자 하였다.

• Journal of Powder Materials
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• v.25 no.1
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• pp.7-11
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• 2018

In this study, we synthesize tungsten oxide thin films by electrodeposition and characterize their electrochromic properties. Depending on the deposition modes, compact and porous tungsten oxide films are fabricated on a transparent indium tin oxide (ITO) substrate. The morphology and crystal structure of the electrodeposited tungsten oxide thin films are investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). X-ray photoelectron spectroscopy is employed to verify the chemical composition and the oxidation state of the films. Compared to the compact tungsten oxides, the porous films show superior electrochemical activities with higher reversibility during electrochemical reactions. Furthermore, they exhibit very high color contrast (97.0%) and switching speed (3.1 and 3.2 s). The outstanding electrochromic performances of the porous tungsten oxide thin films are mainly attributed to the porous structure, which facilitates ion intercalation/deintercalation during electrochemical reactions.

• Educational Technology International
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• v.13 no.2
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• pp.257-281
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• 2012

This study aims to examine individual perceptions and lived experiences of the Net generation of student teachers and the previous generation of teachers about their technology use in education. The participants of this study include 106 pre-service teachers and 50 in-service teachers from one teacher education university in Korea. Employing a mixed methodology, we first empirically examined the participants' perceptions toward multiple variables related to technology use in education, namely (a) past ICT experiences in schools, (b) personal computer use, (c) constructivist belief, (d) computer efficacy, (e) attitude toward computer in education, and (f) prospective computer use. In addition, we conducted face-to-face interviews with selected participants for the in-depth investigation of their lived experiences about technology use, beliefs, and attitude. Results indicate that there are significant differences between in-service and pre-service teachers in their prior experiences with technology in schools. However, the pre-service and in-service teachers did not differ significantly in their beliefs, attitude and other technology-related variables, which may indicate the danger of generational determinism in the Net Generation debate. The analysis of interview narratives revealed two major themes about the interplay of one's agency and structural changes in the participants' lived experiences with technology use in education: (a) transition from negative past experiences to opportunities for positive computer use, and (b) attitudes formation and change through apprenticeship experiences and structural influences. In conclusion, this study suggests that the Net Generation debate should move beyond dichotomous or techno-centric thinking. There is a critical need to pay more attention to develop deeper understandings of the fundamental diversity existing within the generation itself. Implications for teacher education are also discussed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.697-706
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• 2000

In this paper, new bandpass filters that are composed of microstrip ring resonators with the center frequency of 5.775 GHz and the bandwidth of 100 MHz are presented. For the suppression of the unnecessary harmonics, lowpass filters are inserted into the feedlines and ring resonator itself, respectively These bandpass filters show good microwave characteristics with the harmonic suppression ratio of about 39 dB and 35 dB, respectively. Also, the varactor-tuned microstip ring bandpass filter with harmonic suppression is suggested and the tuning bandwidth of more than 450 MHz is obtained.

• The Journal of Korean Association of Computer Education
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• v.10 no.1
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• pp.55-66
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• 2007

To improve access to the learning opportunities of students with disabilities, this study is to identify the potential of the information communication technology in education for the disabilities and to suggest the policy reforms for the special education technology. To answer it, the related literatures of other developed countries and Korea were collected and analyzed by desirability and feasibility as criteria. From the view of the desirability, this study found that the policies of special education in Korea were still regarded as subsidiary and separated from the general students. Moreover, from the view of the feasibility, the law and financial support was relatively insufficient than other countries to implement the policy more effectively and stably. To solve these problems, this study suggests the policy reforms in Korea as five areas and seven tasks.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1608-1611
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• 2009

Here the hydrogen passivation treatment has been adopted to enhance the performance of poly-Si crystallized by YAG laser annealing (LA poly-Si). We have investigated the effects of passivation time, passivation power and passivation temperature on the hall mobility of the LA poly-Si and analyzed the mechanism of the hydrogen passivation preliminary. It has been found that the quality of the poly-Si annealed by YAG laser could be improved after proper hydrogen plasma treatment.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.164-171
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• 2021

The europium sorption on Tamusu clay was investigated by batch sorption experiments and spectroscopic study under the condition of strong ionic strength. The results demonstrated that europium sorption on Tamusu clay increased rapidly with pH value, but decreased with the ionic strength of solution increased. The europium sorption also increased in the presence of humic acid, especially at low pH value. The sorption could be fitted by Freundlich isotherm model and the europium sorption on clay was spontaneous and endothermic reaction. Besides, the result indicates that ion exchange was the main process at low pH value, while inner-sphere surface complexation dominated the sorption process at high pH value. The Backscatter electron scanning/Energy Dispersive Spectrometer(BSE/EDS) and the effect of Na for europium sorption results further suggested that europium sorption on Tamusu clay mainly competed with Na at low pH value. Overall, the results in this research were of significance to understand the sorption behavior of europium on the geological media under high ionic strength.

• Journal of Practical Engineering Education
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• v.14 no.3
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• pp.459-469
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• 2022

The purpose of this study is to explore the educational effect by developing and applying a decision tree-based artificial intelligence convergence education program. To achieve the purpose of this study, the study was conducted through a three-step process of preparation, development, and improvement. In addition, it consisted of four stages of the creative problem-solving process: 'Understanding the problem', 'Idea search and development', 'realization' and 'evaluation'. In particular, the artificial intelligence convergence education program developed in this study is an unplugged activity that does not include programming. Therefore, it is very noteworthy that artificial intelligence convergence education was implemented in subjects other than technology and home economics education, and information education, which are part of junior engineering education, and practical arts education in elementary education, which is a subject that learns Artificial Intelligence technology including programming during class time. In other words, it shows that AI technology can be integrated and taught in most subjects, not specific subjects and has great significance in that it can utilize the concepts and principles of artificial intelligence technology when teaching the concept of classification, which is included in the curriculum.