• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.61.2-61.2
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• 2011

넓은 밴드갭을 가지고 있어 가시광에서 투명하며 높은 이동도를 가진 산화물 반도체는 기존의 Si 기반 TFT 소자를 대체할 차세대 디스플레이의 핵심 소재기술로 관심이 높아지고 있다. 그러나 대표적인 산화물 반도체인 In-Ga-Zn-O (IGZO)에 포함된 인듐의 수요 증가에 따른 가격 급등 문제로 이를 대체할 수 있는 새로운 산화물 반도체 재료에 대한 연구의 필요성이 대두되고 있다. 이에 비교적 저가의 물질로 구성된 Zn-Sn-O계 산화물 소재에 대한 연구가 진행된 바 있으나, 높은 수준의 캐리어 농도를 가지고 있어 TFT 채널용 반도체소재로 적용되기 위해서는 이를 $10^{17}\;cm^{-3}$ 이하로 조절할 수 있는 기술개발이 요구된다. 본 연구는 마그네트론 스퍼터링법을 이용하여 증착된 Ga-Zn-Sn-O (GZTO) 박막의 갈륨 첨가에 따른 특성변화를 조사하였다. GZO ($Ga_2O_3$ 5wt%)와 $SnO_2$ 타켓의 인가 파워를 고정한 상태에서 $Ga_2O_3$ 타켓의 인가 파워를 0~100W로 조절하여 박막 내 Ga 함량을 증가시켰다. 제조된 모든 GZTO 박막은 Ga함량에 관계없이 비정질 구조를 가지며 가시광 영역에서 약 78%의 우수한 투과율을 나타낸다. Ga 함량에 따라 박막의 구조적, 광학적 특성은 크게 변하지 않지만 전기적 특성은 뚜렷한 변화를 나타냈다. $Ga_2O_3$ 파워가 증가할수록 박막 내 캐리어 농도와 이동도의 감소로 비저항이 크게 증가하는데 특히 캐리어 농도는 $Ga_2O_3$ 파워가 0에서 100W로 증가할 때 $2{\times}10^{18}$에서 $8{\times}10^{14}\;cm^{-3}$으로 감소하였다. 이는 Ga-O의 화학적 결합 에너지가 다른 원소들(Zn 또는 In)에 비해 커서 박막 내 산소공공의 감소가 야기되었기 때문이다. 이러한 전기물성의 변화를 이해하기 위해 XPS 분석을 수행하였다. 제조된 GZTO 박막은 $Ga_2O_3$ 파워가 증가함에 따라 O 1s peak에서 산소공공과 관련된 530.8 eV peak의 intensity가 감소한다. 따라서 Ga을 첨가에 따른 캐리어 농도의 감소는 산소공공의 발생억제로 기인한 것으로 판단되며, 본 연구결과는 ZTO계 비정질 산화물 반도체의 활용가능성을 제시하였다.

• Informatization Policy
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• v.19 no.3
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• pp.64-93
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• 2012

This paper attempts to empirically verify the theoretical assumption that ICT factors actually affect national economic development. To this end, this study uses a research model, 'balance model of supply-demand', which consists of IT supply, IT demand and IT policy dimensions. Also, this paper employs several socio-economic factors such as 'size of population', 'consumer price increase', 'national transparency', and 'education'as the moderating variables. The result through the panel data analysis finds it statistically relevant to relate the ICT capacity to each country's economic growth. Also, the study finds that moderating variables were highlighted as important elements of national development: these variables actually moderate the ICT capacity's effects on each surveyed nation's economic growth. Finally, this paper suggests policy implications that nations should consider when developing national informatization policies to drive national economic growth.

• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.33-41
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• 2013

This study was performed to analyse cause of quality deterioration using byproduct of plywood and to determine physical and mechanical properties of particleboard used new bonding condition we found. The result of bending strength of Com-Ply board using EMDI is 57.7 $N/mm^2$ on linear direction and 25.1 $N/mm^2$ on vertical direction. EMDI has better water-resisting qualities than Urea formaldehyde adhesive according to result of thickness swelling and water absorption test. Pre-treatment soaked particle 72 hours in water caused increase of HCHO emission.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.33-39
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• 2009

The practice of supplying nutrients for paddy soil with sustaining human health and ecological soundness is to utilize indicators considering soil chemical reactions. The long-term basis experiment of fertilizer and amendment of paddy soil and an experiment of yield response of soil types on nitrogen level from 2000 till 2002were used to search indicators of nutrient supplying capacity related to soil chemical reactions. Chemical reactions of paddy soil was composed of dissociating and/or adsorbing nutrients and of decomposing soil organic matter (SOM) into $H^+$, $e^-$, $CO_2$ in paddy soil. The indicators of nutrient supplying capacity, which were established by considering soil chemical reactions, were SOM or soil protein for nitrogen and available phosphate for phosphorus and cation exchangeable capacity (CEC) and exchangeable potassium for potassium. Korea has used fertilizer recommendation equations established with the indicators of nutrient supplying capacity for paddy soil.

• Food Science and Preservation
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• v.17 no.2
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• pp.208-213
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• 2010

We sought to optimize parboiled rice preparations with respect to nutritional composition and to compare the physicochemical properties of polished, glutinous rices and Olbyossal (parboiled rice). Crude lipid contents (all w/w) were: brown glutinous rice (1.92%) > Olbyossal (1.13%) > glutinous rice (1.08%) > polished rice (0.32%). The crude ash content of Olbyossal was greater than that of polished rice. There was no significant difference in crude protein level between Olbyossal and polished rice. Total dietary fiber content (all figures are w/w) was higher in Olbyossal (3.79%) than in polished rice (1.67%). With respect to mineral content, P (249.16 mg%), K (144.67 mg%), Na (35.41 mg%), and Mg (30.24 mg%) levels were higher in Olbyossal than in polished rice. There was no significant difference in fatty acid or amino acid content between polished rice and Olbyossal. The L value (lightness) of Olbyossal was lower than that of polished rice but the hardness of Olbyossal was greater.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.301-313
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• 2014

This study aimed to identify the correlation of stress-coping, humor sense, and adaptation to college of nursing students. Three hundred thirty eight subjects completed a structured questionnaire in June 2012. Data were analyzed using SPSS/WIN 21.0 program. The mean scores were as follows; stress-coping 43.33, humor sense 72.18, and adaptation to college 68.02. It meant beyond the intermediate level. Significant differences were found between adaptation to college scores and general characteristics such as gender, academic year, family type, economic status, campus life satisfaction, relation with faculties, grade, and the relationship with the opposite gender. There was significant but weak correlation of stress-coping, humor sense, and adaptation to college. These results suggest that it is necessary to develop individualized education programs considering students' characteristics. Additionally, university adjustment related factors should be studied.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.340-346
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• 2003

This study was carried out to improve cultivation techniques by low cost and labour saving in ginseng (Panax ginseng C. A. Meyer) seedling production, by elucidating proper ratio virgin soil and organic fertilizer, suitable height of front piller. The obtained results are as follows ; The optimal ratio of white decomposition of virgin soil and organic fertilizer was 10:1 for good yield of standard seedling, The fittest height of front piller was 150 cm because of both good seedling growth and yield. The cost for production of seedling of ginseng could be reduced by both optimal ratio of virgin soil, organic fertilizer and selection of front piller height.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.10
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• pp.39-46
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• 1999

In this paper, we propose new hardware architecture of a fast searcher for an initial code acquisition in wideband CDMA wireless local loop systems. The proposed searcher uses double-dwell serial search algorithm and has N active correlators for the high performance code acquisition. Since the N active correlators are designed with pipelined architecture, it is possible to reduce the hardware complexity with only one energy calculation. Our architecture is designed using VHDL to meet wideband CDMA wireless local loop standard and verified under JTC wideband channels. Average code acquisition time of the proposed fast searcher which has 16 correlators is about 40 seconds in case of initial installation and 0.16 seconds when a base station is known. The verified fast searcher is synthesized with in $0.6\mu\textrm{m}$ LG library. The synthesized searcher has 15.8K rates when the number of 4he correlators is 16.

• The Journal of Society for e-Business Studies
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• v.14 no.1
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• pp.93-120
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• 2009

Content services on the Internet is getting attention as a new business model, selling digital content in real-time on the web. However, most of these content-based business is based on advertisement model rather than direct-payment-based business model. One of the difficulty in setting up charge-based content service is that the pricing paradigm of digital content is different from traditional pricing of products or services. The objective of this study is to empirically derive the feasible price response functions for these content services. Based on conjoint analysis of popular attributes of digital content, several price response function models were fitted against the conjoint data, using online movie viewers' preferences for different attributes of the service. Fitted function models were linear, multiplicative, exponential, attraction, and Gutenberg models. attraction model was found to be well-fit with the data for several specific combinations of attributes. Implications for pricing strategy is discussed at the end.

• The Journal of Korean Association of Computer Education
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• v.16 no.5
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• pp.9-16
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• 2013

Computational thinking is an ability to resolve problems that may be applied to the various real world problems and is regarded as the core of computer science. Computational thinking may be improved through experiences of analyzing problems and of selecting, applying, and modeling strategies appropriate for problem-solving. In order to enhance computational thinking of learners, it is important to provide experiences of solving various problems. This study designed puzzle based learning in order to educate learners principles of problem solving, let them have experiences of interest and insight, and provide them with problem solving experiences. The puzzle questions used for learning were classified into six types - constraints, optimization, probability, statistics, pattern recognition, and strategies. These questions were applied to Informatics gifted elementary students and, after their education, their computational thinking and problem solving inventory significantly improved.