• 산업기술연구
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• 제19권
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• pp.25-29
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• 1999

Rotary bending fatigue tests were carried out to investigate the fatigue behavior of high performance ductile cast iron experienced super rapid induction heat treatment. The effect of super rapid induction treatment on fatigue limit was experimentally examined with the special focus on the variation surface microstructure and the fatigue crack initiation and propagation through fractography. Main results obtained are as follows. By super rapid induction treatment in FCD500, the martensite structure obtained through conventional quenching heat treatment was confirmed on the specimen surface. The fatigue crack initiation in the hardened surface layer was restricted by the martensite structure and compressive residual stress. Thus, it could be interpreted that the initiation stress would be increased by the improvement of surface structure. The fatigue crack propagation in the hardened layer was retarded by the presence of the globular shape martensite around the graphite nodule and compressive residual stress. The crack propagation path has shown zigzag pattern in the hardened surface layer.

• 대한기계학회논문집A
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• 제26권4호
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• pp.596-601
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• 2002

Rotary bending fatigue tests were carried out to investigate the fatigue characteristics of high performance ductile cast iron experienced super rapid induction treatment. The influence of super rapid induction treatment on fatigue limit was experimentally examined with the special focus on the variation of surface microstructure and the fatigue crack initiation and propagation through fractography. Main results obtained are as follows. By super rapid induction treatment in FCD500, the martensite structure obtained through conventional heat treatment was confirmed on the specimen surface. The fatigue crack initiation in the hardened surface layer was restricted by the martensite structure and compressive residual stress. Thus, it could be interpreted that the initiation stress would be increased by improved structure in the surface. The fatigue crack propagation in the hardened layer was retarded by the presence of the globular shape martensite around the graphite nodule and compressive residual stress and the crack propagation behavior has zigzag pattern in the hardened surface layer.

• 열처리공학회지
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• 제22권2호
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• pp.108-115
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• 2009

• International journal of advanced smart convergence
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• 제10권2호
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• pp.37-44
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• 2021

At the time of entering the super-aged society, the health problem of the elderly is becoming more prominent due to the rapid digital era caused by COVID-19, but the gap between welfare budgets and welfare benefits according to regional characteristics is still not narrowed and there is a significant difference in emergency medical access. In response, this study proposes an ICT-based New Normal Smart Care System (NNSCS) to bridge the gap I n health and medical problems. This is an integrated system model that links the elderly themselves to health care, self-diagnosis, disease prediction and prevention, and emergency medical services. The purpose is to apply location-based technology and motion recognition technology under smartphones and smartwatches (wearable) environments to detect health care and risks, predict and diagnose diseases using health and medical big data, and minimize treatment latency. Through the New Normal Smart Care System (NNSCS), which links health care, prevention, and rapid emergency treatment with easy and simple access to health care for the elderly, it aims to minimize health gaps and solve health problems for the elderly.

• 한국해양공학회지
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• 제23권4호
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• pp.52-57
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• 2009

The effect of aging treatment on the microstructure and mechanical properties of super duplex stainless steel with W was investigated. The phase was precipitated mainly at the early stage of aging and a lower aging temperature under $750^{\circ}C$, but the phase was formed after long-term aging treatment between $600^{\circ}C$ and $900^{\circ}C$. The volume fraction of the phase increased with aging temperature up to $750^{\circ}C$ and then decreased up to $900^{\circ}C$. With an increase in the aging time, the volume fraction phase at the early stage of aging increased slightly, and then increased rapidly beyond a certain time. The rapid increase in the tensile strength and hardness and decrease in the elongation and impact toughness were measured with aging temperatures up to $750^{\circ}C$. On the other hand, the tensile strength and hardness decreased slightly, and the elongation and Charpy impact toughness were unchanged with aging temperatures over $750^{\circ}C$. The tensile strength and hardness increased rapidly at the early stage of aging, and then increased slowly beyond a certain time. The elongation and Charpy impact toughness decreased rapidly at the early stage of aging, and then remained unchanged beyond a certain time. The phase that formed at the early stage of aging and the lower aging temperature had a considerable effect on the elongation and Charpy impact toughness of the super duplex stainless steel with W.

• 한국환경보건학회지
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• 제30권5호
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• pp.410-416
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• 2004

The objective of this investigation was to evaluate applicability of precoat filtration that can be substituted for rapid sand filter of conventional water treatment system(CWTS). Precoat filter used in this experiment are candle filter. Element disk of candle are pore size $10{\mu}m(R),\;20{\mu}m(B)$ And diatomaceous earth are cake pore size $3.5{\mu}m$(Standard Super- Cel; A), $7{\mu}m$(Hyflo Super-Cel; B) and $17{\mu}m$(Celite 545RV; C). $2kg/m^2$ diatomaceous earth is used for precoating, it coated candle in $5{\sim}6mm$ thickness. 1. Al adsorption dosages by diatomaceous earth used in experimental we Hyflo Super-Cel 0.843mg/g, Standard Super-Cel 0.782 mg/g and Celite 545RV 0.766 mg/g. 2. Filtrate of precoat filter during 60min are R-C combination 20.7($m^3/m^2$)>B-C 18.3($m^3/m^2$)>B-B 15.0($m^3/m^2$)> R-B 12.9($m^3/m^2$)> R-A 11,093($l/m^2$). 3. Water quality of precoat filter effluent are thus. $KMnO_4$ consumption are $1.10{\sim}2.20mg/l$, removal rate are $30.9{\sim}65.6\%$. They are R-A 1.10(mg/l)(removal rate $65.6\%$). R-C(2.20 mg/l)(removal rate $30.9\%$). 4. $Al^{3+}$ are not detected with all combination, removal rate $100\%$. 5. Considering water quality and flux, continued running time of R-A combination is 7 hr. Accumulated filtrate are $74.4 m^3/m^2$, average flux is $177.2 l/m^2{\cdot}min$. And filtrate per diatomaceous earth 1g are 37.2 l. 6. R-A effluent's water quality are $KMnO_4$ Consumption 1.10(mg/l), DOC 1.161 mg/1, Al 0.0 mg/1, $UV_{254}$ 0.016/cm, Turbidity 0.1(NTU). R-A combination is suitable to precoat filtration for the settling basin effluent treatment.

• 한국세라믹학회지
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• 제51권6호
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• pp.570-574
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• 2014

Magnetic-graphene nanosheets have been synthesized via a simple effective chemical precipitation method followed by heat treatment. The composite nanosheets are super paramagnetic at room temperature and can be separated by an external magnetic field. The prepared magnetic-graphene nanosheets were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and BET surface area analysis. The results demonstrated the successful attachment of iron oxide nanoparticles to graphene nanosheets. It was found that the attached nanoparticles were mainly $Fe_3O_4$. The magnetic-graphene nanosheets showed near complete methyl orange removal within 10 mintues and would be practically usable for methyl orange separation from water.

• 농업생명과학연구
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• 제51권1호
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• pp.35-43
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• 2017

본 연구에서는 인도 수출용 옥수수의 품종육성을 위하여 인도 현지에서 수집한 다양한 옥수수의 계통과 품종에 대한 내습성 실험을 수행하였다. 실험대상은 총 20종의 인도수집 옥수수 계통 및 품종과 국내시판종인 광평옥과 찰옥수수를 이용하였다. 내습성검정을 위하여 하우스 내에 물웅덩이를 설치하고 화분에서 재배한 대조구와 화분을 침수시킨 침수처리구로 구분하여 2주간 재배한 후 초장의 길이를 비교한 결과 일반구에 대한 침수구의 비율이 높은 H2(92.9%), H18(88.8%), CN114A(98.1%), CN351A(94.3%), Super900M(95.3%), P3394(98.8%), 31N27(96.7%) 등은 비교적 내습성이 강한 것으로 나타났으며 반면에 H1(78.9%), H8(73.4%), H10(77.1%), H19(79.0%), H26(74.1%), H31(75.7%), H34(77.5%), H36(77.4%), H40(74.6%) 등은 침수시 많은 수분스트레스를 받는 것으로 사려된다. 침수상태의 옥수수 잎으로부터 엽록소a, 엽록소b 및 cartenoids의 함량을 측정하여 대조구와 비교함으로서 침수상태에서 얼마나 많은 엽록소와 cartenoids가 감소되었는지 검정해보니 상기 결과와 동일한 결과를 도출하였다. 특히 H36($7.249ug{\cdot}mg^{-1}$)과 H40($7.642ug{\cdot}mg^{-1}$)의 경우 엽록소a의 함량이 침수시 급감함을 보여주었다. 반면에 인도시판종인 37N27($0.630ug{\cdot}mg^{-1}$)과 P3394($1.208ug{\cdot}mg^{-1}$)는 가장 적은 함량의 변화를 나타내어 우수한 품종임을 알 수 있었다. cartenoids의 함량감소는 엽록체 a의 함량변화와 비례하며 감소하는 경향을 나타내었다.

• 한국유통학회지:유통연구
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• 제15권5호
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• pp.237-255
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• 2010

국내 약사법에서는 약 판매를 약국에 한정하고 있다. 이로 인해 심야나 공휴일에 약 구입이 어려워 소비자 선택폭이 제한되어 소비자 불편이 가중되고 있다. 또한 급속한 고령화의 진전은 노인의료비를 급격히 증가시켜 국가 의료보험 재정을 악화시키는 요인으로 작용하고 있다. 한편 미국, 일본 등 선진국들은 자가치료(self-medication)를 지원하는 관점에서 안전성과 유효성이 검증된 일반의약품에 대해서는 편의점이나 슈퍼마켓 등 일반 소매점에서의 판매를 허용하고 있다. 특히, 세계적으로 안전추구 경향이 강한 일본은 급증하는 의료비를 억제하기 위해 일반의약품의 판매채널을 다양화하였고, 그 결과 경제, 사회분야에 다음과 같은 다양한 규제완화 효과를 얻게 되었다. 첫째, 일반의약품의 유통채널이 약국에서 일반 소매점포로까지 확대되면서 잠재수요가 유발되어 관련시장이 확대되었다. 둘째, 판매채널 간 경쟁이 촉진되면서 의약품 가격이 하락했다. 셋째, 의약품 판매채널 증가로 소비자의 선택폭이 확대되었고 소비자 이용 편리성이 증대되었다. 넷째, 판매채널 다원화로 경쟁 환경이 조성되면서 기업의 경쟁력 제고 노력을 가속화시켰다. 다섯째, 자가치료 환경조성을 통해 의료비 재정건전성 제고 기반을 마련했다. 국내 65세 이상 인구는 2000년에 7%를 넘어섰고 2018년에는 14%를 웃돌 것으로 보여 국민의료비 증가는 가속화될 전망이다. 우리도 의료선진국과 같이 고령화시대를 대비하는 차원에서 일반의약품의 판매처를 다양화하여 자가치료 환경을 조성함으로써 개인의료비 지출을 줄이고, 국가의료보험 재정건전성을 제고하며, 나아가 소비자 후생을 증진시켜나가야 할 것이다.