• Resources Recycling
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• v.12 no.3
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• pp.25-30
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• 2003

The synthesis of SiC used for the parts of the gas turbine and the heat exchanger, was carried out. In this study, wire cutting slurry of silicon wafer and the graphite rod of spent zinc-carbon battery were applied to the starting materials for the synthesis. The powders of Si or Si+SiC were obtained from the waste material by filtration, gravity separation and magnetic separation. Graphite powder was produced by dismantling, grinding and gravity separation from spent zinc-carbon battery. The synthesis of SiC could be completed from the mixture powders of Si and C or Si+SiC and C at the condition of equivalent ratio of Si and C, atmosphere of Ar or vacuum, temperature of above 1$600^{\circ}C$ and 2 hours reactions. The purity of synthesized Si-C was above 99%.

• Journal of Family Resource Management and Policy Review
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• v.26 no.3
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• pp.19-34
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• 2022

There are growing concerns about debt insolvency among youth and low-income households. The deterioration in household debt quality among young people is due to a combination of sluggish employment, an increase in student loan burden and an increase in high-interest loans from the secondary financial sector. The purpose of this study was to explore the possibility of household debt default among young borrowers in Korea and to predict the factors affecting this possibility. This study utilized the 2021 Household Finance and Welfare Survey and used random forest algorithm to comprehensively analyze factors related to the possibility of default risk among young adults. This study presented the importance index and partial dependence charts of major determinants. This study found that the ratio of debt to assets(DTA), medical costs, household default risk index (HDRI), communication costs, and housing costs the focal independent variables.

• Vending industry
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• v.7 no.1 s.19
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• pp.72-75
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• 2007

최근 신1000권 지폐식별기 관련업체들은 초긴장 상태이다. 메가톤급이라 할 만큼 파급력 있는 시장 특수가 목전에 두고 있는 듯 하나 아직 교체수요가 본격화되고 있지 못하고 있다. 지폐식별기를 교체해야 하는 운영업체들은 그다지 급할 게 없다는 입장이다. 서두르기보다는 사후문제를 최소화하는 쪽에 비중을 두고 경쟁력있고 믿을 만한 제품을 선별하고 있는 중이다. 따라서 시장특수를 누리는 수혜업체는 모든 지폐식별기 공급업체를 대상으로 할 수 없다. 남다른 경쟁력을 갖추지 않고서는 살아남을 수 없는 절박한 시장상황이다. 관련업체들이 경쟁력을 강화하기 위해 사활을 건 경쟁을 벌이고 있는 가운데 최근 삼원자판기의 행보가 큰 주목을 받고 있다. 삼원자판기는 오랜 서비스 전문업체의 노하우를 살려 심혈을 기울여 개발한 LV77 신.구권 병행 지폐식별기를 가지고 당당한 시장 출사표를 던졌다. 신1000권 교체시장의 일대 시장돌풍을 노리는 삼원자판기의 의욕에 찬 사업 행보를 따라가 봤다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.237-238
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• 2000

전복양식산업은90년대 이후 비약적으로 발전하여 현재는 남해안을 중심으로 전국적으로 넙치양식과 함께 육상수조 및 해상양식에서 큰 비중을 차지하고 있다. 1999년도의 양식현황은 종묘생산 건수가 177건, 수면적 6만7천$m^2$, 연간 생산능력 5천5백만 마리로 나타나고 있으며, 지역별 생산 능력은 남해안 및 제주도가 전국대비 각각 62%, 5.9%, 동해안은 6.3%, 서해안은 25.4%를 차지하고 있다. 이처럼 전복양식 산업의 꾸준한 발달과 규모의 증가 추세로 인하여 전복 종묘에서부터 성패까지 성장 단계별로 선별. 분산기회가 많아지고, 성패의 출하시기에도 많은 양의 박리가 이루어지기 때문에 효율적이고 경제적인 박리방법이 필요하다. 특히, 일시에 대량으로 마취 박리를 할 수 있고, 생물에 대한 상처로 인한 폐사를 줄일 수 있는 안정적이고 효율적인 마취박리 방법이 절실히 요구되고 있다. (중략)

• Analytical Science and Technology
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• v.20 no.6
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• pp.516-523
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• 2007

Purification of silica mineral has been investigated by acid leaching of pulverized silica. A series of studies has been carried out on the effect of leaching silica powder as a function of the leaching time at the constant temperature of $80^{\circ}C$ in oxalic acid, aqua regia, and two mixed acids of HF/HCl, $HF/HNO_3$. The impurities of silica and leachantes were measured by neutron activation analysis (NAA), inductively coupled plasma atomic emission spectrometry (ICP-AES), atomic absorption spectrometry, x-ray fluorescence (XRF) method and wet analysis (WA). Certain metals, such as sodium, calcium, iron, aluminium and titanium, have been found in concentrations of hundreds or even thousands of mg/kg. Comparison of purification processes of silica and analytical methods of impurities in the silica was conducted in this study.

• Resources Recycling
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• v.16 no.5
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• pp.57-64
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• 2007

Triboelectrostatic separation of mixed three kinds of plastics, PVC, PET and PMMA, in the range of similar gravity has been performed through a two-stage separation process. Polypropylene (PP) and high-impact polystyrene (HIPS) were found to be the most effective materials for a tribo-charger in the separation of PVC, PET and PMMA. In the 1st stage using the PP cyclone charger, PVC grade and recovery depended considerably on the air velocity (10 m/s), the relative humidity (<30%), the electric field (>200 kV/m) and the splitter position (+2 cm from the center) in the triboelelctrostatic separator unit. At an optimum condition a PVC grade of 99.6% and a recovery of 97.5% was achieved. In the 2nd stage using the HIPS cyclone charger, a PMMA grade of 98.3% and a recovery of 97.0% was obtained under the conditions of 10m/s air velocity, over 250 kV/m electric field, central splitter position and less than 40% relative humidity.

• Journal of the Mineralogical Society of Korea
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• v.27 no.3
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• pp.149-158
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• 2014

Consolidants were extended use for conservation of weathered stone heritage. Epoxy, acryl, isocyanate, and alkoxysilane consolidants are most commonly used products. Consolidant of 1T1G_5 wt 0.08 % that consists of T (TEOS: Tetraethyl Orthosilicate) and G (GPTMS: 3-Glycidoxy propyl trimethoxy silane) were used this study. A shore hardness values show increasing after treated with consolidant in granite. Surface brightness after treated with consolidant are changing slightly dark but turns the original color over time. Ultra-sonic velocity is increased after treated with consolidant but slightly reduced over time to remain constant. It has the advantage of being effective after treated with consolidant in granite and efficiency of consolidation increase with slow velocity before treated with consolidant.

• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.89-96
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• 2012

In this study landslide causal factors which are considered to have the same effect in assessment techniques are categorized and their impact on landslides is analyzed to acquire reasonable weighting factors in the landslide hazard. Results are compared to those of the Assessment Chart developed by National Institute for Disaster Prevention (NIDP) and the adequacy and proper portion for landslide causal factors are considered. The Artificial Neural Network (ANN) method applied to 28 landslide areas is incorporated to evaluate the reasonable rating. Results show that the following items in the Chart are necessary to modify their portions in order to implement the precise assessment results: 1) Estimated damage; 2) Tension crack; 3) Existence of valley.

• 한국벤처창업학회:학술대회논문집
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• 2017.11a
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• pp.71-74
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• 2017

본 연구에서는 농업벤처기업의 활성화를 위해 경영현황 및 애로사항, 지원 우선순위 등에 대해 조사하고 분석하였다. 이를 위해 국내 농업벤처기업 103개소를 대상으로 벤처기업협회에서 실시한 설문조사 결과를 분석하였으며, 일반벤처기업 2,098개소, 농림어업 벤처기업 67개소를 대상으로 실시한 벤처기업정밀실태조사 자료를 토대로 비교 분석 연구를 수행하여 다음과 같은 주요 결과를 도출하였다. 첫째, 일반벤처 대비 높은 금융비용과 부채비율, 신규자금에 대한 높은 정부 의존도, 자금조달의 어려움과 벤처 투자 유치 실적이 저조함으로 인해 농업벤처기업의 재정 여건은 매우 열악한 환경에 있는 것으로 나타났다. 이를 극복하기 위한 방안으로 농산물 중부가가치가 높고 수출 가능한 품목을 선별하여 육성하는 투자 방안이 필요하며, 정부 보조금과 지원금 매칭 펀드 방식의 혼합 지원 및 크라우드 펀딩의 활용 검토가 필요하다. 둘째, 농업벤처는 일반벤처에 비해 R&D투자보다는 설비투자 비중이 높으나 연구개발 자금지원을 가장 필요한 방안 1순위로 꼽고 있으며, 자가 기술을 활용하여 비즈니스 모델화하는 데 어려움이 많은 것으로 파악되었다. 또한 제조업 기업 비중이 63.2%를 차지하고 있어 사업 분야의 편중이 높은 것으로 나타났다. 이와 같은 결과를 고려하여 해외시장을 고려한 제품 연구개발 및 생산원가 경쟁력 확보, 그리고 관련 분야 투자유치와 고용 창출이 필요하다. 또한 개발된 기술의 사업화 지원을 위해 투자 기반 사업화 추진과 제조업 외 다양한 분야의 육성이 필요하다. 셋째, 사업규모가 적고 기업이 안정화되지 못해 신규인력 확보 및 유지에 어려움을 겪고 있는 것으로 나타났다. 인력확보의 활성화를 위한 방안으로는 지속적인 농업 인력 감소에 대응하여 스마트농업 가능 인력의 양성이 필요하며, 농업벤처 지원 교육의 체계화와 효율화를 위한 컨트롤타워가 필요하다. 넷째, 국내외 판로개척에 대한 애로사항이 가장 높은 것으로 나타났다. 이를 위한 지원 방안으로 관 주도의 수출지원정책에서 민간참여 위주로 정책 방향 변경이 필요하며, 수출대상국에 적합한 전략적 농산물 및 가공식품 생산이 필요하다.

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.278-285
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• 2019

The experiment was implemented to gain basic data for stable proso millet (Panicum miliaceum L.) production through germination viability and establishment uniformity based on seed refining under seed selection with specific gravity of proso millet seed. Seeds of three proso millet cultivars were carefully selected by adjusting NaCl into 9 levels (1.000, 1.005, 1.010, 1.015, 1.020, 1.025, 1.030, 1.035, 1.04 g·L^-1), and their standard germination rate, seeding quality and field emergence rate were investigated. Proso millets showed heavier thousand seed weight as specific gravity high. In standard germination, all of the 3 cultivars of selected seeding showed at least 91% germination rate. With respect to the 1.040 g·L^-1 selection by specific gravity, 'Hwanggeum' had 98.9%, 'Ibaekchal', 99.4%, and 'Hwangsilchal', 98.9%, recording the highest. Seeding quality was investigated and it was found that, compared with the non-selected seeds, selected seeds had longer plant heights and averaged 2.0, 2.2 and 1.9 cm, respectably. In terms of leaf length, only 'Hwanggeum' and 'Ibaekchal' showed distinctive differences. No significance was found in stem diameter and SPAD. The seeds selected using specific gravity all had longer or heavier average root length, root weight and stem weight. Compared with non-selected seeds, the specific gravity of 1.040 g·L^-1 had longer root lengths of 2.9, 3.0 and 2.9 cm. 1.040 g·L^-1 was also found to have the heaviest root weight, and stem weight. The field emergence viability investigation found significance solely in the mean emergence time (MET) by the cultivar. High significance was found in percent emergence (PE) and emergence rate index (ERI) in the specific gravity for the selection of seeds. All of the three cultivars showed higher PE and ERI as specific gravity selection high. The 1.040 g·L^-1 specific gravity selection had the highest PE of 90.7, 85.3 and 92.8%. For productivity increase based on improved proso millet germination rate and enhanced establishment uniformity, it seems favorable to employ 1.040 g·L^-1 specific gravity selection using salt solution.