• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.75-80
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• 2015

To train convergence experts ICT infrastructure must be learned IoT use capabilities of things. In this paper, targeted to students that are majoring in computer science, and for the design of the curriculum and the educational model that handles education of operation in general for training IoT-related education for five months to experts of convergence training describe the contents. Course is the basic ability of the process, core competence course, is divided into real-life capability process and on-site training course, was constructed in a total of 10 stages of the process details. Curriculum, it was designed to learn sensing technology, network technology, security, and content production technology. This educational model is utilized for job creation human resource training project of 2015 Ministry of Employment and Labor, it demonstrated the utility to contribute in order to achieve a high completion and the employment rate. Applicable to future university education plans to expand the curriculum, including courses that complement the Java.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.5
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• pp.263-267
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• 2017

The Co-Cr as-cast alloys are widely used in the manufacturing of orthopedic implants made with investment casting techniques because of its high strength, good corrosion resistance and excellent biocompatibility properties. Carbide precipitation at grain boundaries and interdendritic regions is the major strenthening mechanism in the as-cast condition. In this study, effects of GPS (Gas Pressured Sintering) heat-treatment on the microstructure and crystallinity of the as-cast Co-Cr alloy prepared by investment casting were investigated. It was confirmed that the content of metal carbide ($Cr_{23}C_6$) was increased in the grain boundary by using optical microscopy (OM), field-emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS).

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.116-116
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• 2009

마그네슘 합금은 구조용으로 사용 가능한 금속 재료 중 가장 가벼운 소재이며, 동시에 비강도 및 비강성과 같은 기계적 특성이 우수하여 알루미늄 합금의 뒤를 이을 차세대 경량 재료로써 주목을 받고 있다. 더욱이 석유자원의 대부분을 소비하고 있는 운송기기 분야에서는 경량화를 통한 연비향상과 배출가스 저감이 가장 큰 과제이며, 이 문제를 해결하기 위한 노력의 일환으로 최경량 소재인 마그네슘 합금의 사용량은 더욱 증가할 것으로 기대된다. 한편 기존의 마그네슘 합금 관련 연구는 새로운 합금의 개발에 치우쳐 있었으며, 상대적으로 이들 합금을 활용하기 위한 가공기술, 특히 용접에 대한 연구는 아직까지 많이 부족한 실정이다. 이는 철강재와 비교하여 마그네슘 합금의 고유물성이 용접의 관점에서는 상당히 열악하기 때문으로, 마그네슘은 융점 및 비점은 낮은 반면, 증기압과 열전도율은 높고 표면장력 및 점성은 낮은 특성을 가지고 있다. 그러므로 타 공법에 비해 상대적으로 입열이 적고 고속용접이 가능한 레이저의 적용이 최적으로 판단된다. 따라서 본 연구에서는 Nd:YAG 레이저를 사용하여 압연판재로 상용화되어 있는 AZ31B 마그네슘 합금의 맞대기 용접성을 조사하였으며, 용접부의 미세조직과 용접조건에 따른 용접부의 기계적 특성을 비교 및 검토하였다. 용접부의 기계적 특성은 인장 및 경도시험을 통해 평가하였다. 그 결과 레이저 출력 1.2kW를 적용한 경우에 안정적인 강도를 얻을 수 있었으며 레이저 출력 1.5kW, 용접속도 80mm/sec의 조건에서 모재 인장강도 대비 103% 그리고 연신율 대비 47.1%의 최적의 결과가 얻어졌다. 또한 용접부의 경도는 모재와 동등하거나 다소 높은 수준이었다. 이는 용접시 용접부내 잔류하는 알루미늄에 의한 고용 강화 효과와 금속간화합물의 석출 빈도 증가, 그리고 레이저 용접의 특징인 급열급랭 공정에 기인한 결정립 미세화의 영향 때문으로 사료된다. 한편 용접부 미세조직을 관찰한 결과, 열영향부의 존재는 두드러지지 않았으며 용융경계부에서는 주상정이, 그리고 용접부 가운데에서는 등축정이 관찰되었다.

• Korean Journal of Materials Research
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• v.7 no.1
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• pp.50-56
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• 1997

급냉응고법을 이용하여 고용한도 이상으로 Mn량을 첨가할 때 Mn량에 따른 인장특성의 변화와 시효특성을 조사하였다. 원심분무법으로 AI-4.7%Zn-2.5%Mg-0.2%Zr합금에 Mn량을 각기 달리 첨가한 급냉응고 분말을 제조 하였다. 이 분말을 냉간압축, 진공 탈가스처리를 한 후 15:1로 압출하여 봉상 시편을 만들었다. 분말의 미세조직은 $\alpha$-AI수지상과 수지상간 편석부로 이루어져 있으며 Mn첨가에 따라 조직의 변화는 관찰되지 않았다. 빠른 냉각속도로 인하여 2.0%Mn을 첨가한 경우에도 초정 Mn상을 발견할 수 없었다. 압출재의 미세조직은 아결정립으로 이루어져 있으며 약간의 제2상들이 관찰되었다. 대부분의 Mn 분산상은 압출후 용체화처리 과정에서 형성되었으며 시효경화량은 Mn양에 관계없이 일정하였다. 46$0^{\circ}C$에서 1시간 용체화처리하고 12$0^{\circ}C$에서 24시간 시효처리한 경우 최대의 시효경도값을 나타내었다. 인장강도는 Mn첨가량에 따라 증가 하였는데 이것은 Mn분산상의 밀도증가에 의한 것으로 확인되었다. 2.0%Mn을 첨가한 합금의 시효후 인장강도는 590MPa, 연산율은 4%를 보였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4749-4755
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• 2014

In this study, to maximize the heat release from the heat generating environment, such as a high-capacity inverter, the heat release performance of the extruded-type heat sinks with the variation of the base thickness were investigated using the experimental and numerical methods. The base thickness was varied from 5 to 14 mm. The heat release was characterized by the amount of heat released through the heat sink, the surface temperature of heat sink base between the heat sources, and temperature of heat sources. The surface temperatures between heat sources and the amounts of heat release were improved more as the base thickness was decreased. In contrast, the temperatures of the heat sources decreased with increasing base thickness. Based on the case study of these heat sinks, it is believed that a heat sink with a 9.5mm-thick base was optimized for the heat release.

• Journal of the Korean Magnetics Society
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• v.13 no.6
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• pp.246-250
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• 2003

The electromagnetic properties of Ni$\_$0.8/Zn$\_$0.2/Fe$_2$O$_4$ having stable characteristics in high frequency range were investigated as functions of Bi$_2$O$_3$, CaO contents. Power loss increased in proportion to the amount of Bi$_2$O$_3$ up to 0.3 wt％ and decreased over 0.3 wt％. Also, permeability increased with Bi$_2$O$_3$ contents. The lowest power loss and highest resonance frequency were obtained to the specimens added Bi$_2$O$_3$ of 0.7wt％ and CaO of 0.3 wt％ due to creation of resistivity layers in the grain boundaries originated by the solid solution of Bi$_2$O$_3$ and CaO.

• Journal of Digital Convergence
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• v.14 no.9
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• pp.89-97
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• 2016

Intellectual property rights play a key role in employment creation and income generation plays an important role, especially in the creative economy. Many companies are ultimately increasing efforts to boost the company's financial performance, such as maximizing profits by building a strong brand assets amid committed to brand management in this paradigm. Reasonable evaluation and commercialization of technology transactions, financial assistance, investment decisions, trademark brand value for the reactivation (revitalizing) for the purposes of M & A, litigation, brand strategy will be said to be very important. In spite of the importance, the awareness of the property and the capabilities to assess are hardly sufficient. Thus, this study, targeting companies with valid trademarks for value assessment, conducted case analysis by cost method and income approach; the analysis presented the result from 2.05 million by the cost method to 2.7 million by the income approach applied to a variable discount rate and adjustment contribution. However, now that the implication was drawn from a single company, further studies covering case study and application plan according to scale and type of diverse company groups should be continued.

• Korean Chemical Engineering Research
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• v.55 no.2
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• pp.163-169
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• 2017

In order to investigate the electrochemical properties and the particle size effect of $LiNi_{1-x-y}Co_xAl_yO_2$ (x=0.15, y=0.045 or 0.05, NCA) for lithium ion batteries (LIBs), two commercial NCA cathode materials (NCA#1, NCA#2) were used as cathode materials for LIB. The average particle size of the NCA#1 which consisted of uniform spherical particles was found to be approximately $5m{\mu}$. NCA#2 consisted of particles with bimodal size distribution of approximately $5m{\mu}$ and $11m{\mu}$. From the results of charge-discharge performance test, a high initial discharge capacity of 197.0 mAh/g was obtained with NCA#2, which is a higher value than that with NCA#1. The cycle retentions of NCA#1 and NCA#2 up to 30 cycles were 92% and 94%, respectively.

• Journal of Science Education
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• v.33 no.1
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• pp.100-110
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• 2009

This study analyzes the factors influencing interest on scientific subject and its change in Korean youth by using a sample from KEEP(Korea Education and Employment Panel 1-4) data. The results are as follows: First, the interest on scientific subject of Korean youth show quadratic curve. Also, the interrelationship between intercept and slope of subject interest is -.205 but it is not statistically significant Second, analysis of Latent Growth Models shows that self-esteem, academic achievement, school culture/climates and high school tracks are found to be a statistically significant factor on the intercept of subject interest These findings indicate that the interest on scientific subject of the Korean youth show a quadratic curve and various factors such as self-esteem, academic achievement and school culture/climates are much more influential on it.

• Journal of Sensor Science and Technology
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• v.8 no.3
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• pp.291-297
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• 1999

The plasma etching of tungsten thin films has been studied with $SF_6$ gas in RIE system. The etch rate of ${\alpha}$-phase W film with $SF_6$ gas plasma has been showed to depend strongly on process parameters ($SF_6$, $SF_6-N_2$ gas). Effect of $N_2$ addition and etching selectivity between W film and photoresist have also been studied in detail. Etching profiles between W film and photoresist were investigated by SEM. The compounds on W surface after $SF_6-N_2$ gas plasma treatment were examined by XPS and the concentration of F ions was detected by OES during plasma on.