• 한국환경과학회지
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• 제30권12호
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• pp.1041-1051
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• 2021

The purpose of this study was to identify for extenders, adhesives, colorants, and fungicides suitable for the production of high-quality film-coated seeds of Chinese cabbage. In addition, the effect of various additives used for film coating on the germination of coated seeds and seedling vigor was investigated to establish appropriate treatment conditions for film coating efficiency. The germination rate and germination speed in Chinese cabbage film-coated seeds did not differ significantly depending on the type and concentration of the extender, while the use of Talc resulted in superior granulation capacity and adhesion of the seed coat in comparison to Zeolite. There was no significant difference in the germination rate depending on the type of adhesive used for film coating of Chinese cabbage seeds, but the germination rate was slightly slower in the film-coated seeds using carboxymethyl cellulose as an adhesive. On the other hand, the seeds coated with a film using 1% PVA as an adhesive not only maintained hardness enough to withstand external pressure, but also showed a high germination rate. In addition, the suitable disinfectant for film coating was venoram, and the treatment concentration was good at 250 mg·L^-1. The type of colorant used in the film-coated seeds of Chinese cabbage did not significantly affect the germination rate, germination speed, and seedling vigor. The seeds film-coated using the liquid colorant were superior in appearance to the seeds film-coated with the solid colorant, which implies the possibility of reduction in the manufacturing costs by using the water-soluble paints as colorants for film-coated seeds.

• 전기전자학회논문지
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• 제26권2호
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• pp.219-225
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• 2022

우리나라의 섬유산업 중 염색가공 분야는 에너지 다소비 업종으로, 노동 집약적 특성에 따라 원단위 생산성이 낮고, 대부분 중소·영세기업 특징이 있다. 염색 원단의 불량률이 높아지면 재염색으로 인한 생산단가 상승과 초과 에너지 투입으로 비용이 증가하기 때문에, 불량률을 최소를 통한 생산량 향상이 초점이었다. 또한 고온고압의 환경에서 이루어지는 염색공정은 사고 위험으로 염색기 원단 투입구를 실시간으로 개방할 수 없기 때문에 실시간으로 원단의 염색상태 확인이 어려웠다. 최근에는 염액을 실시간으로 모니터링하는 연구가 활발히 진행중이다. 본 논문에서는 탁도, pH, 전도도 센서를 이용하여 염액의 흡진율을 계측할 수 있는 복합센서 흡진율 모델 및 구성시스템을 제안하였으며, 실험방법소개와 실험결과 분석을 실시하였다.

• 한국의류산업학회지
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• 제24권2호
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• pp.206-216
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• 2022

This study sought to examine the sustainability criteria found in the global sourcing practices of global fashion retailers. Sustainable supply chain management, with a particular focus on the sustainability criteria of global sourcing, was analyzed. This qualitative study was based on a focus group interview and corporate social responsibility (CSR) annual reports. Eight master categories, 18 middle categories, and 37 bottom categories were extracted. The key categories and their middle categories were as follows: (1) Social compliance (working conditions, employment, safety); (2) Environment concerns (environmental pollution management, eco-friendly production, supply chain environment); (3) Energy efficiency (energy saving program, store environment); (4) Consumer protection (restricted substances management, consumer product safety improvement); (5) Management system (code of conduct, triangle audit system); (6) Community social activities (local community service, voluntary activities, charitable activities); (7) External stakeholder engagement (media & non-governmental organization management, maintenance of relationship with local authority); (8) Brand protection (respect for companies' intellectual property). The findings of this study offer academically significant insights into the sustainability criteria that can be encountered by companies under diverse global sourcing scenarios, revealing that global sourcing by fashion retailers is not merely a means of reducing costs, but a way of generating new jobs and making a social contribution to developing countries. The study's findings also have practical significance, offering guidelines for general CSR activities in the global sourcing process.

• 한국지반환경공학회 논문집
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• 제23권7호
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• pp.5-10
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• 2022

산업폐기물은 국내외적으로 공간 및 환경적 측면에서 큰 문제가 되고 있다. 따라서 이를 해결하려는 방법으로 페기물 감량화 및 재활용 정책이 실시되고 있다. 산업폐기물인 엔지니어드스톤 슬러지는 엔지니어드스톤 생산 과정에서 발생한다. 엔지니어드스톤 슬러지는 대부분 매립으로 처리되기 때문에 발생량 증가는 매립공간 및 처리비용을 증가시킨다. 그러므로 엔지니어드스톤 슬러지를 자원화 시킬 수 있는 방법이 필요하다. 이에 본 연구에서는 엔지니어드스톤 슬러지에 화강풍화토를 혼합한 혼합 복토재를 매립지의 복토재로서 활용 가능성을 확인하기 위한 목적으로 실내시험(액소성시험, 다짐시험, 일축압축시험, 투수시험)을 수행하였다. 그 결과 엔지니어드스톤 슬러지의 함유량이 62.5% 미만인 엔지니어드스톤 슬러지 혼합 복토재가 매립지의 복토재로 활용할 수 있을 것으로 판단된다.

• 전력전자학회논문지
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• 제27권1호
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• pp.26-32
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• 2022

This paper proposes a power system that includes a 120k W fuel cell DC-DC converter (FDC) and 30 kW bidirectional DC-DC converter (BHDC) for a 150 kW fuel-cell vehicle. With a high DC link voltage of 800 V, the efficiency and power density of the power electronic components are improved. Through the modular design of FDC and BHDC, electric components are shared, resulting in reduced mass production costs. The switching frequency of 30 kHz of full SiC devices and optimal design of coupled inductor reduce the volume, achieving a power density of 8.3 kW/L. Furthermore, a synergetic operation strategy using variable limiter control of FDC and BHDC was proposed to efficiently operate the fuel cell vehicle considering the fuel cell stack efficiency according to the load. Finally, the performance of the prototype was verified by Highway Fuel Economy Driving Schedule testing, EMI test, and the linked operation between FDC and BHDC. The full load efficiencies of the FDC and BHDC prototypes are 98.47% and 98.74%, respectively.

• 자원리싸이클링
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• 제30권2호
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• pp.61-67
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• 2021

밀링 및 터닝 가공 중 발생되는 칩 형태 타이타늄 스크랩을 세라믹스 원료로 활용하기 위한 연구를 수행하였다. 우선, 칩 형태 타이타늄 스크랩에 포함되어 있는 다량의 절삭유와 철 성분 제거를 위해 유기세정 및 산 세정 과정을 거쳐 스크랩 표면 세척을 진행하였다. 아세톤과 질산을 사용한 세정 과정을 통해 스크랩 내 유기물과 철 함량은 5 wt.% 수준에서 0.07 wt.% 이하로 감소하는 것을 확인하였고 세정에 이어진 산화 과정을 통해 타이타늄 스크랩은 이산화타이타늄화 되었다. 타이타늄 스크랩의 이산화타이타늄화 과정은 800 ℃ 이상의 온도에서 이루어졌으며 이산화타이타늄은 고에너지 밀링 과정을 통해 나노 결정립으로 미세화되어 탄소에 의한 환원 및 탄화 반응은 기존 이산화타이타늄 탄화환원 온도인 1500 ℃보다 낮은 1200 ℃에서 가능하게 되었다. 이산화타이타늄 탄화환원을 통해 얻어지는 타이타늄 탄화물은 질소 및 타이타늄 이외 전이금속 원소의 첨가 및 고용을 통해 물성이 개선될 수 있었다. 타이타늄 탄화물 내 질소 첨가 및 고용상 형성 가능성은 열역학 계산을 통해 예측되었고 질소 첨가 및 전이금속 고용에 의해 타이타늄 탄화물의 특성 중 경도 및 파괴인성 제어가 가능하였다.

• 고무기술
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• 제22권2호
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• pp.119-149
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• 2021

Domestic materials & components industry is making a shift from quantitative growth to qualitative growth, while the paradigm of a future society is changing rapidly to energy, mobility, smartification and etc. The main features of materials & components industry are analyzed broadly based on three aspects that are: ① industry Status, ② the value chain structure, ③ the competitiveness. With regard to the national aspect, it is shown that the number of an export and a trade surplus increased consistently after the government advanced the policy on materials & components and Korea's trade deficit with Japan has been decreased. Moreover, the state's export ranking increased from tenth place in 2001 into sixth place in 2017, dedicating to the growth of a national economy. The analysis of the chain value indicates that specifications of an end product are set when the materials & components are combined with manpower, infrastructure and technologies. In terms of the competitiveness, it requires a long time and high costs to develop technologies on materials and it is important for components to have a process innovation and credibility wired. Following the industry structure with priority given on materials, Jeonnam Province accounts for 14.8% of national material production. As a result of analyzing Jeonnam's export competitiveness, it is measured that a serious polarization exists, revealing there are 6 major technology industries by 11 categories for materials & components, Jeonnam has presented 6 major materials & components considering the key industry and the new industry in future to remedy the mentioned problem so far, and plans to knock on the industry development through 10 different strategies.

• 인간식물환경학회지
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• 제23권5호
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• pp.545-554
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• 2020

Background and objective: Moth orchids in the vegetative stage are suitable for a multi-layer growing environment in a closed-type plant factory which can be a good alternative that can reduce production costs by reducing cultivation time and energy cost per plant. This study was conducted to find out the optimal rhizospheric environment for different irrigation methods without a potting medium and rhizospheric ventilation for the vegetative growth of young Phalaenopsis hybrid 'Blanc Rouge' (P. KV600 × P. Kang 1) and Phalaenopsis Queen Beer 'Mantefon' in a closed-type plant factory system. Methods: The one-month-old clonal micropropagules with bare roots rapped with a sponges were fixed on the holes of styrofoam plates above growth beds, and were watered using the ebb-and-flow (EBB) and aeroponic (AER) methods with Ichihashi solution (0.5 strength) once a day at 06:00 (P) or 18:00 (S), and both (PS). Rhizospheric ventilation (V) was also applied to change the temperature, relative humidity, and CO₂ concentration of the beds. Plants potted into sphagnum moss and watered once a week were used as the control group. Results: After 12 months of treatment, the growth characteristics of the EBB groups were the best among the treatment groups without a medium, but no effect of irrigation timing was observed. V reduced the temperature, relative humidity and CO₂ concentration of the beds. Whereas, EBB+V (ebb-and-flow with ventilation) improved plant growth and reduced the occurrence of disorders and withering. Especially, EBB+V showed a similar performance to the control group. Conclusion: The results indicated that the optimal irrigation method without a potting medium for producing middle-aged potted moth orchids was the EBB system with forced rhizospheric ventilation. Therefore, further studies on the optimal ventilation method and moisture control of the crown need to be carried out to develop the irrigation system without a potting medium for vertical farming in closed-type plant factories.

• 한국기계가공학회지
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• 제21권4호
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• pp.60-69
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• 2022

To keep pace with Industry 4.0, it is imperative for companies to redesign their working environments by adopting robotic automation systems. Automation lines are facilitating the latest cutting-edge technologies, such as 3D vision and industrial robots, to outdo competitors by reducing costs. Considering the nature of the manufacturing industry, a time-saving workflow and smooth linkwork between processes is vital. At Dellics, without any additional new installation in the automation lines, only a few improvements to the working process could raise productivity. Three requirements are the development of gripping technology by utilizing a 3D vision system for the recognition of the material shape and location, research on lighting projectors to target long distances and high illumination, and testing of algorithms/software to improve measurement accuracy and identify products. With some of the functional requisites mentioned above, improved robotic automation systems should provide an improved working environment to maximize overall production efficiency. In this article, the ways in which such a system can become the groundwork for establishing an unmanned working infrastructure are discussed.

• 한국유기농업학회지
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• 제30권2호
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• pp.207-230
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• 2022

A survey on the understanding of environment-friendly certification system was conducted for certified operators. The survey included the necessity of certification system, difficulties in producing certified products, and general evaluation of the current certification system. Certified operators were generally satisfied with the certification system in terms of the certification standards, the public subsidy programs, and the farm management costs. Individuals with parallel production farms were relatively less satisfied than the group with full-time organic farmers. Analysis using the ranking probit model indicated that the longer the certification experience, the more highly aware the need for the certification system was. Our results indicated that policy strategies are needed to enlarge the marketability of environment-friendly agricultural products since economic factors of organic products were the most important factor for maintaining and expanding certification in overseas as well as in Korea. It seems to be necessary to implement economic triggers for certified operators to continue their certification programs by promoting the transition period certification for individual farms in parallel with conventional agriculture. Analysis of the variables correlated with the expansion of environment-friendly agriculture by the logit model implied that certified operators with the younger age and higher annual incomes were more likely to expand environment-friendly agriculture. Therefore, it might also be important to provide financial support and incentives for new entry farmers to participate in environment-friendly agriculture and establish a system to share the know-how of successful certified organic farmers.