• Journal of The Korean Association of Information Education
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• v.24 no.4
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• pp.279-289
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• 2020

The purpose of this study is to apply the training program for teachers to strengthen the competence of artificial intelligence education in primary and secondary school teachers and to analyze its effectiveness and analyze teachers' demands for artificial intelligence education to provide basic research data. The referenced training program was designed based on the ADDIE model by selecting the educational contents based on the five core elements of AI, and teachers from the G Metropolitan Office of Education and the AI Education Research Association collaborated to develop the program. The effectiveness of the developed program and questionnaire of teacher needs analysis for AI teaching were examined for content validity. As a result of the training conducted by applying the developed program, satisfaction with each curriculum of the training and the possibility of application to the field were highly evaluated. It was found that teachers consider the need of teaching unplugged activities for AI education and basic AI experiences in elementary school level, and AI education contents including block programming languages and physical computing activities are needed to teach in middle school level.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.13-24
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• 1988

This paper is concentrated on the development of oxygen transfer system by U-tube deep shaft in biological fluidised bed process. The depth of the shaft is 32 m, it is composed of downcomer and riser. Not only flow pattern and oxygen transfer in the deep shaft but also oxygen limitation in biofilm and oxygen utilization in biological fluidised bed are investigated. In this investigation, driving force for liquid circulation in the deep shaft is affected by air injection depth and gas hold-up in downcomer. Flow pattern of the deep shaft is revealed to plug flow. When flow velocity in the deep shaft is maintained to 0.52 m/sec, $K_La$ value is peak at 25~30 m depth in riser. The efficiency of dissolved oxygen supply which passed from the deep shaft to biological fluidised bed is estimated to 56~81 % in the organic wastewater treatment using the deep shaft and when dissolved oxygen concentration is 9.2 mg/l and over, limiting factors of flux and substrate within biofilm are organic materials. Terefore, organic loadings could be increase without decreasing of BOD removal efficiency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.432-436
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• 2002

This study was conducted in 2001 to determine the influence of seed-piece size (SPS) and number (SPN) per mini-tuber produced by hydroponics on growth and yield of potato (Solanum tuberosum L.). Treatments consisted of the combination of six SPS (3, 5, 7, 9, 11, 13g/seed-piece) and four SPN (whole tuber, and two, three, and four pieces/tuber). Percentage sprout emergence at transplanting was higher for seed pieces weighing 7 to 13 g (83.0 to 85.4%) and for three and four pieces per tuber (85.4 and 84.8%). As SPS were increased from 3 to 9 g/piece, total yields markedly increased from 2,052 to 2,924 kg/10a and seed tuber (31 to 250 g) yield from 1,589 to 2,428kg/10a with no further increase with SPS. As SPN was increased from one to three/ tuber, total yields increased from 1,918 to 2,982 kg/10a and seed tuber yields from 1,422 to 2,579 kg/10a with no further increase with SPN. Average tuber weight increased with SPS (46.3 to 71.5 g/tuber) and SPN (56.5 to 64.9 g/tuber).

• Journal of the Korean Institute of Gas
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• v.15 no.5
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• pp.50-56
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• 2011

A preliminary experimental study of new concept air hybrid engine, which stores compressed air in the tank during braking and re-use it to propel vehicle during crusing or acceleration, was carried out in this study. A single cylinder engine was modified to realize the concept of air hybrid engine. Independent variable valve lift system was adopted in one of the exhaust valves to store the compressed air into the air tank during compression period. An air injector module was installed in the place of spark plug, and the stored compressed air was supplied during the expansion period to realize air motoring mode. For air compression mode, the tank with volume of 30 liter could be charged up to more than 13 bar. By utilizing this stored compressed air, motoring work of 0.41 bar of IMEP(Indicated mean effective pressure) at maximum can be generated at the 800rpm conditions, which is higher than the case of normal idle condition by 1.1 bar of IMEP.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.147-154
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• 2018

This paper focuses on the development of a support system that can rapidly generate the design data of a hot-form die with cooling channels, commonly known as hot stamping technology. We propose a new process for designing hot-form dies based on our (automated) system, whose main features are derived from the analysis of the design requirements and design process in the current industry. Our design support system consists of two modules, which allow for the generation of a 3D geometry model and its 2D drawings. The module for 3D modeling automation is implemented as a type of CATIA template model based on CATIA V5 Knowledgeware. This module automatically creates a 3D model of a hot-form die, including the cooling channels, that depends on the shape of the forming surface and the number of STEELs (subsets of die product) and cooling channels. It also allows for both the editing of the positions and orientations of the cooling channels and testing for the purpose of satisfying the constraints on the distance between the forming surface and cooling channels. Another module for the auto-generation of the 2D drawings is being developed as a plug-in using CAA (CATIA SDK) and Visual C++. Our system was evaluated using the S/W test based on a user defined scenario. As a result, it was shown that it can generate a 3D model of a hot form die and its 2D drawings with hole tables about 29 times faster than the conventional manual method without any design errors.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2442-2450
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• 2010

Using sensor devices applied to various objects will be needed wireless network that it is easy to install in them. Tiny devices configured to processor that bas comparatively low computing ability are inappropriate to use devices that are wireless LAN, etc. In result, network devices needed to not only have simple communication protocol, but have Plug and Play function that it works as soon as it connects without installing any device driver. it also will industrially have both low power and low cost because of mobility of it. From IEEE 802.11 standard, WPAN(Wireless Personal Area Network) included in LAN is being developed by WPAN WG(Working Group) on area with low power consumption and low complexity. In addition to, it is standardizing MAC and PRY of the standard that is expected to wirelessly communicate within 10m. WPAN will be used generally in the more near future because of both low power and low cost of Zigbee. In this paper we designed zigbee based user authentication module for a automotive smart-key system.

• Journal of KIISE:Software and Applications
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• v.31 no.8
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• pp.1027-1042
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• 2004

A Software Component is a module that is reused among a lot of projects, systems, and companies rather than a single application. Components can be reused in various systems if they provide not only the common functionalities required in many applications but also the diverse aspects to be customized for being suitable for customers' demands. From the development phase, components should be designed and developed considering the variable aspects they have for convenient customization. Easily customized components can be frequently reused in lots of applications. In the literature, there are some modeling and customizing techniques. But they suggested only conceptual or basic methods based on Object-Oriented. And the practical instructions for reusing component were not provided sufficiently. Moreover, there are few techniques that consider the proper variability types components have. Thus, those techniques are not appropriate for applying to black box component completely developed and released. In this paper, we classify variabilities that components have in functional aspect into two categories. The one is logic variability, and the other is workflow variability. For each classified variability, we propose the three kind of modeling techniques, which are selection, plug in and externalization. Also detailed instructions for practical design and application are provided.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.21-26
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• 2011

Differences among cultivars, conditions of nutrient solution, nursing materials, and soilless culture systems were investigated to select suitable cultivar and cultivation methods for stable production of summer spinach in the highlands. The 'Quinto' spinach showed the earliest growth and highest yield. For yield increase of summer spinach, optimal solution pH was 6.0, EC was $2.0dS{\cdot}m^{-1}$, and $NH_4-N$ ratio of nutrient solution was 30 percent Stand rate of spinach in nursing seedlings, at 200-cell-tray filled with mixed nursing soil (peat : perlite = 7 : 3), was higher than those grown in urethane sponge and rock-wool plug. Yield was also 18 to 24 percent higher than those in rock-wool plug and urethane sponge. Plant length and yield of spinach in mixed substrate (peat : perlite = 7 : 3) filled nutrient film technique (MSNFT) system were longer of 18 percent, and higher of 9 percent than those in deep flow technique (DFT) system, respectively. However, changes of root zone temperature, pH and EC showed similar pattern with DFT. Therefore, growing 'Quinto' cultivar at 6.0 of pH, $2.0dS{\cdot}m^{-1}$ of EC, 30 percent of $NH_4-N$ ratio, at 200-cell-tray filled with mixed nursing soil, and MSNFT cultivation system, was the best for production of summer spinach in the highlands.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.209-213
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• 2013

This study was conducted to produce heads of artichoke in July in Korea. The artichoke was planted in the Autumn and it could be reaped heads of artichokes in late of May in Korea. It can inform us that the artichoke need under some low temperature during the Winter to open flowers. In order to harvest heads of artichoke in the Summer two kinds of cultivar 'Green Globe' and 'Imperial Star' those were grown for 4 weeks in green house of $17^{\circ}C$ which were treated at 3, 6, 9 and $12^{\circ}C$ chamber for 4 weeks and then planted the 8th April. Plant distance was $150{\times}50$ cm. After 3 months most of artichoke of 'Imperial Star (IS)' made heads. Especially, the artichokes 'IS' were treated at $6^{\circ}C$ made heads 63% of plants but those at $12^{\circ}C$ made heads 33% and the artichokes (no treatment at low temperature) grown in greenhouse at $17^{\circ}C$ for 8 weeks made heads 5% of plants. 'Green Globe (GG)' made heads 28% of plants at $9^{\circ}C$ and 10% at $12^{\circ}C$, and 'GG' grown in greenhouse at $17^{\circ}C$ for 8 weeks never had made any head. The weights of head were 97 g and 86 g in 'IS' and 'GG' respectively. The yield of heads were 215 and 108 kg/10a in 'IS' and 'GG' respectively.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.686-693
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• 2012

To develop a technique for mass-propagation of virus-free sweet potato [Ipomoea batatas (L.) Lam.] plant using nutrient film technique (NFT), the growth characteristics of 4 cultivars as affected by nutrient solution composition and cutting size were investigated. 72 cells (35 mL/cell) plug trays filled with vermiculite and perlite (1:1, v/v) were used. Vine length, fresh and dry weights of virus-free plants were the greatest in the nutrient solution recommended by National Horticultural Research Station in Japan, followed by that recommended by National Institute of Horticultural & Herbal Science in Korea, and Yamazaki's nutrient solution for lettuce. The growth of uppershoot cuttings was the best among 4 subsections of cutting. Vine length, and fresh and dry weights increased in the longer cutting treatments, and were better in 'Shinzami' and 'Yeonhwangmi' than those in 'Mannami' and 'Shincheonmi'. Vine diameter and length of the longest root were not significantly affected by the cutting size and cutting source. The growth characteristics of the single node cutting were not significantly different from those in 2-node cutting. The efficiency of rapid mass-propagation could be promoted with single node cuttings and uppershoot cuttings grown in NFT system.