• 한국수소및신에너지학회논문집
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• 제33권2호
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• pp.148-157
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• 2022

Research on hydrogen storage is active to properly deal with hydrogen, which is considered a next-generation energy medium. In particular, research on metal hydride with excellent safety and energy efficiency has attracted attention, and among them, magnesium-based hydrogen storage alloys have been studied for a long time due to their high storage density, low cost, and abundance. However, Mg-based alloys require high temperature conditions due to strong binding enthalpy, and have many difficulties due to slow hydrogenation kinetics and reduction in hydrogen storage capacity due to oxidation, and various strategies have been proposed for this. This research manufactured Mg₂Ni to improve hydrogenation kinetics and synthesize about 5, 10, 20 wt% of CaF₂ as a catalyst for controlling oxidation. Mg₂NiHx-CaF₂ produced by hydrogen induced mechanical alloying analyzed hydrogenation kinetics through an automatic PCT measurement system under conditions of 423 K, 523 K, and 623 K. In addition, material life cycle assessment was conducted through Gabi software and CML 2001 and Eco-Indicator 99' methodology, and the environmental impact characteristics of the manufacturing process of the composites were analyzed. In conclusion, it was found that the effects of resource depletion (ARD) and fossil fuels had a higher burden than other impact categories.

• 멤브레인
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• 제25권2호
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• pp.191-201
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• 2015

$TiCo_xFe_{1-x}$(x=0.50~1.00)계 합금을 제조하고, 합금의 특성을 X-ray diffractometer (XRD), pressure composition temperature (PCT)곡선, scanning electron microscopy (SEM)에 의해 조사하였고, $TiCo_xFe_{1-x}$(x=0.50~1.00)-stainless steel (SS) 복합막에 대해 $H_2-N_2$ 혼합기체분리실험을 하였다. X-선 회절분석에 의하면 $TiCo_xFe_{1-x}$(x=0.50~1.00)계 합금의 결정구조는 TiCo와 같은 입방정구조이었다. $TiCo_xFe_{1-x}$(x=0.50~1.00)계 합금은 $120^{\circ}C$에서 hysteresis현상을 나타내었고, 합금 중 Fe의 양이 증가함에 따라 x=0.90~1.00과 0.50~0.55 범위에서는 hysteresis가 증가하였고, x=0.55~0.90 범위에서는 감소하였다. 가장 작은 hysteresis를 나타낸 합금은 $TiCo_{0.55}Fe_{0.45}$이었다. $120^{\circ}C$에서 $TiCo_xFe_{1-x}$(x=0.50~1.00)-SS 복합막의 수소투과압력의 최저값은 $TiCo_{0.55}Fe_{0.45}$에서 2.5 atm을 나타내었고, 최대값은 $TiCo_{0.90}Fe_{0.10}$에서 10 atm을 나타내었다. $TiCo_xFe_{1-x}$(x=0.50~.00)-SS 복합막에 의하여 $120^{\circ}C$에서 $H_2-N_2$ 혼합기체를 분리하는 경우, 가장 우수한 복합막은 고압부의 수소투과압력이 2.5 atm으로 가장 낮고, hysteresis가 가장 작은 $TiCo_{0.55}Fe_{0.45}$-SS 복합막이었다.

• 전기전자학회논문지
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• 제27권1호
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• pp.122-126
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• 2023

본 논문에서는 복합 미생물 배양기의 제어시스템을 제안하였다. 제안하는 제어시스템은 복합 미생물 배양기의 제어부, 통신부, 전원부, 제어시스템 등으로 구성된다. 복합 미생물 배양기의 제어부는 아날로그 신호와 디지털 신호의 변환, LCD 패널을 이용한 디스플레이, 수위센서, 온도센서, pH 농도센서 등과 같은 센서들의 신호 제어를 하도록 설계 및 제작한다. 사용하는 수위센서는 기존 수위센서가 거품과 같은 이물질 등으로 인해 측정이 어려운 문제점을 해결하고자 직진성이 우수한 IR 레이저 방식을 사용하여 정확한 수위 측정이 가능하도록 설계 및 제작한다. 온도센서는 열 저항 원리를 사용하여 측정함으로써, 높은 정확도와 누적 저항 오차가 없도록 설계하여 사용한다. 통신부는 2개의 LAN 포트와 1개의 RS-232 포트로 구성하여 복합 미생물 배양기에서 사용되는 LCD 패널, PCT 패널, 로드셀 컨트롤러 등의 신호를 제어부에 전달할 수 있도록 설계 및 제작한다. 전원부는 제어부와 통신부가 원활하게 동작할 수 있도록 24V, 12V 5V 등 3개의 전압 공급 단자로 구성하여 전원을 공급하도록 설계 및 제작한다. 복합 미생물 배양기의 제어시스템은 PLC를 사용하여 pH 농도센서, 온도센서, 수위센서 등의 센서값과 배양에 사용되는 써큘레이션 펌프, 써큘레이션 밸브, 로터리 펌프와 인버터 로드셀 등의 동작을 제어한다. 제안된 복합 미생물 배양기의 제어시스템의 성능을 평가하기 위하여 공인인증기관에서 실험한 결과는 수위 측정감도의 범위가 -0.41mm~1.59mm로, 물 온도의 변화 폭이 ±0.41℃로 현재 상용으로 판매되는 제품들 성능보다 우수한 성능으로 동작됨이 확인되었다. 따라서, 본 논문에서 제안한 복합 미생물 배양기의 제어시스템의 효용성이 입증되었다.

• 동의생리병리학회지
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• 제29권2호
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• pp.115-126
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• 2015

The purpose of this paper is to explore the strategy of future Korean medicine(KM) clinical research through the study on the proposals for KM clinical research worldwide. In this study, the papers published in English through Pubmed were investigated mainly. Among them, we analyzed the methodological proposals from the clinical research papers that were published in the KM related fields. Various proposals for improving the problems in KM clinical studies are as follows. First, KM clinical research should be designed based on understanding for the theory, backgrounds, paradigms and worldviews of KM. In addition, considering the model validity, KM clinical research model should include the diagnosis, interventions and outcomes measurement methods reflecting the characteristics and real practice in KM. The internal validity and external validity should be also taken into account. One of the most important thing is to identify the contents about various and complex 'real practice' in KM. A prospective observational study was suitable for the purpose of this study. Finally, we suggested a few improvement directions for RCTs studies in KM. First, we would be able to improve the quality and the internal validity in KM clinical research using the checklists of CONSORT(Consolidated Standards for Reporting Trials) Statement and STRICTA(Standards for Reporting Interventions in Clinical Trials of Acupuncture). Second, we could use various clinical research methods and the modified research of RCTs such as PCT(pragmatic clinical trial) to reflect the characteristics of actual KM practice. Consequently, we would be able to improve the external validity. Third, the KM diagnosis and outcomes measurement methods should be developed based on an actual KM practice and it should reflect a real practice. The 'pattern identification(辨證)' is the core to KM diagnosis. But in order to be applied to the clinical research, the pattern identification(辨證) should be objectified and standardized. Future KM clinical research model should reflect the characteristics and a real practice in KM. In addition, it should include the advantage of rigorous RCTs research.Specially, the diagnosis, interventions and outcomes measurement methods in KM clinical research should reflect this view.

• 한국산학기술학회논문지
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• 제21권6호
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• pp.455-460
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• 2020

한국, 중국, 일본 정부는 철도에 대한 종합연구기관을 설립하여 운영하고 있다. 한국철도기술연구원, 중국철도과학연구원, 일본철도종합기술연구소는 각 국가의 대표적인 철도종합연구기관으로서, 철도원천기술 및 시스템기술개발에 집중하고 있다. 이 기관들은 특허와 논문 실적을 지속적으로 도출하고 있으며, 특허 및 논문을 통해 각 기관들의 연구성과를 비교 분석할 수 있다. 윈텔립스 DB를 이용하여 2000년 이후 공개특허를 비교한 결과, 특허의 양적 경쟁력에서는 한국철도기술연구원이 1,923건으로 가장 앞서는 것으로 나타났고, 질적 경쟁력에서는 한국철도기술연구원이 토목분야의 특허시장지수가 1.04, 특허영향력지수가 1.33으로 높게 나타났으며 일본철도종합기술연구소가 철도전력분야 특허시장지수가 1.16, 특허영향력지수가 1.32로 높게 나타났다. 세 기관 모두 자국 특허출원 비중이 매우 높게 나타났으나, 한국철도기술연구원이 상대적으로 PCT 출원 108건 등 해외 지식재산권 경쟁력 확보노력을 가장 많이 하는 것으로 나타났다. Scopus DB를 이용하여 논문발표를 비교한 결과, 중국철도과학연구원이 1,527건으로 가장 많은 논문을 발표하였지만, 2015년부터는 한국철도기술연구원이 매년 100건 이상의 논문을 발표하며 가장 많은 실적을 나타냈다. 피인용도를 중심으로 논문영향력을 살펴본 결과, 한국철도기술연구원의 논문영향력지수가 0.45로서 두 기관보다 높은 경쟁력을 갖고 있었다. 향후 세 기관의 특허·논문 정보에 대한 텍스트마이닝 등 빅데이터분석을 활용하여, 기관별 중점연구영역 및 유망기술분야를 도출하고, 과학적 증거에 기반한 철도기술개발 중장기발전계획 등의 수립이 필요할 것으로 판단된다.

• 동의신경정신과학회지
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• 제28권3호
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• pp.231-248
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• 2017

Objectives: This study evaluates anti-stress and sleep-inductive effects of Dongshingihyeolyangsubang (DSGYSB) on rats induced by chronic mild stress (CMS). Methods: Twenty-five healthy rats were randomly divided into five groups: normal, CMS (Control), DSGYSB50, DSGYSB100, and DSGYSBS200. All rats except the normal group were exposed to unpredictable stress conditions such as water deprivation, empty bottles, and forced treadmill. A week after starting the experiment, rats in DSGYSB50, DSGYSB100, and DSGYSB200 groups were fed orally with water once a day for two weeks. Then blood samples were taken from the rats for analysis of complete blood count, AST, ALT, and glucose. Noradrenaline, corticosterone, serotonin, GABA and melatonin were measured by ELISA kit. BDNF, CREB, TrkB and $TNF-{\alpha}$ were measured by RT-PCT. Results: In Noradrenaline contents, the DSGYSB200 group revealed significant decrease compared to the control group. In corticosterone contents, the DSGYSB200 group revealed significant decrease compared to the control group. In serotonin contents, the DSGYSB200 group revealed significant increase compared to the control group. In GABA contents, the DSGYSB50, DSGYSB100, and DSGYSB200 groups revealed significant increase compared to the control group. In the activity of BDNF, the DSGYSB50, DSGYSB100 and DSGYSB200 groups revealed significant increase compared to the control group. In the activity of CREB, the DSGYSB100 and DSGYSB200 groups revealed a significant decrease compared to the control group. In the activity of TrkB, the DSGYSB100 and DSGYSB200 groups revealed significant decrease compared to the control group. In the activity of $TNF-{\alpha}$, DSGYSB100 and DSGYSB200 groups revealed significant decrease compared to the control group. In glucose contents, the DSGYSB100 and DSGYSB200 groups revealed significant decrease compared to the control group. In the leukocyte changes, white blood cells, neutrophil, lymphocytes, and monocyte significantly increased in the DSGYSB100 and DSGYSB200 groups than the control group. In the erythrocyte changes, hemoglobin significantly increased in the DSGYSB200 group than the control group. Conclusions: Results suggest that Dongshingihyeolyangsubang has anti-stress and sleep-inductive effects on rats induced by CMS.

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.31-38
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• 2006

There are two types of metal hydride electrodes as a negative electrode in a Ni-MH battery, $AB_2$ Zr-based Laves phases and $AB_5$ LM(La-rich mischmetal)-based alloys. The $AB_5$ alloy electrodes have characteristic properties such as a large discharge capacity per volume, easiness in activation, long cycle life and a low cost of alloy. However they have a relatively small discharge capacity per weight. The $AB_2$alloy electrodes have a much higher discharge capacity per weight than $AB_5$ alloy electrodes, however they have some disadvantages of poor activation behavior and cycle life. Therefore, in order to improve the discharge capacity of the $AB_5$ alloy electrode the Zr, Ti and V which are the alloying elements of the $AB_2$ alloys were added to the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy which was chosen as a $AB_5$ alloy with a high capacity. The addition of Zr, Ti and V to $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}$ alloy improved the activation to be completed in two cycles. The discharge capacities of Zr 0.02, Ti 0.02 and V 0.1 alloys in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) were respectively 346, 348 and 366 mAh/g alloy. The alloy electrodes, Zr 0.02, Ti 0.05 and V 0.1 in $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V), have shown good cycle property after 200 cycles. The rate capability of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloy electrodes were very good until 0.6 C rate and the alloys, Zr 0.02, Ti 0.05 and V 0.1, have shown the best result as 92 % at 2.4 C rate. The charge retention property of the $LaNi_{3.6}Ai_{0.4}Co_{0.7}Mn_{0.3}M_y$ (M = Zr, Ti, V) alloys was not good and the alloys with M content from 0.02 to 0.05 showed better charge retention properties.

• 동의신경정신과학회지
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• 제28권1호
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• pp.25-38
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• 2017

Objectives: The study aims were to evaluate the Anti-stress and Sleep-inductive effects of Yunjogyosim-tang (YJGS) in rats induced by Chronic Mild Stress (CMS). Methods: 25 healthy Rats were randomly divided into 5 groups; Normal, CMS (Control), YJGS 50, YJGS 100, and YJGS 200. All rats except the normal group were exposed to random stress conditions like water deprivation, empty bottles, forced runs on the treadmill, etc. according to the timetable of CSM for 3 weeks. After a week starting the experiment, Rats in YJGS 50, YJGS 100, and YJGS 200 groups were fed orally once a day for 2 weeks. Blood samples were taken afterward from each rat for analysis of Complete blood count, AST, ALT, and glucose levels. Corticosterone, serotonin, and melatonin were measured by ELISA kit. BDNF and $TNF-{\alpha}$ were measured by RT-PCT. Results: 1. Corticosterone levels were lower in YJGS 50, and YJGS 200 groups compared to the control group. 2. Serotonin levels were lower in the YJGS 100 and YJGS 200 groups compared to the control group. 3. Melatonin levels were higher in the YJGS 50 group compared to the control group. 4. Activity levels were higher in the BDNF, and YJGS 50 groups compared to the control group. 5. In the Activity of $TNF-{\alpha}$, YJGS 50 group showed a significant decrease compared to the control group. 6. In the Glucose content, YJGS 50, YJGS 100, and YJGS 200 groups showed a significant decrease compared to the control group. 7. When analyzing leukocytes, monocytes were found to be increased in YJGS 100 and YJGS 200 groups compared to the control group. 8. When analyzing red blood cells, more changes occurred to erythrocytes and thrombocytes in the YJGS 50 and YJGS 200 groups than in the control group. Hemoglobin was significantly increased in the YJGS 100 group and platelet levels were significantly increased in all experimental groups compared with the control group. Conclusions: These results suggest that Yunjogyosim-tang has anti-stress and sleep-inductive effects on rats induced by CMS.

• 한국수소및신에너지학회논문집
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• 제16권2호
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• pp.122-129
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• 2005

The characteristics of hydrogen storage have been investigated in the Ti-Cr-Mo and Ti-Cr-V ternary alloys with bcc structure. The alloys were melted by arc furnace and remelted 4-5 times for homogeneity. The lattice parameters, microstructures and phases of the alloys were examined by SEM, EDX and XRD, and the Pressure-Composition isotherms of the alloys were measured. From these data the relationship of the maximum and effective hydrogen storage capacities vs. chemical composition, lattice parameter and the radius of tetrahedral site were analyzed and discussed. The results showed that all of these alloy, in the range of the this study, had mainly bcc solid solutions with small amount of Ti segregation due to a lower melting point of Ti compared with other elements. Lattice parameters of the alloys were very near to the atomic average values of lattice parameters of the constituent elements. It was also found that maximum hydrogen storage capacities of the Ti-Cr-Mo alloys increased with increasing Ti content and the radius of tetrahedral site but the effective hydrogen storage capacities decreased after showing the maximum. The hydrogen storage capacities of the Ti-Cr-V alloys were almost same even though the V contens were quite different from alloy to alloy and this could be attributed to the almost same Ti/Cr ratio of the alloys. The maximum effective hydrogen storage capacity of the Ti-Cr-Mo alloys was revealed at Ti content of about 40${\sim}$50 at% and radius of tetrahedral site of 0.43${\sim}$0.45 nm. The Ti-Cr-V alloys showed the hydrogen storage capacities of 3.0 wt% and effective hydrogen storage capacities of 1.5 wt%.

• 한국세라믹학회지
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• 제38권9호
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• pp.839-845
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• 2001

원자력발전소에서 발생하는 폐수지, 잡고체, 붕산폐액을 유리화 하기 위하여 폐기물별 조성을 바탕으로 유리조성 연구를 수행하였다. 폐수지, 잡고체를 각각 유리화 할 수 있는 두 개 의 후보유리 RG-1과 DG-1 그리고 폐수지, 잡고체, 붕산폐액을 혼합하여 처리할 수 있는 후보유리 MG-1을 개발하였다. 각 후보유리에 대해 운전변수, 고화체 품질, 가용 효과를 평가하였으며 일부 특성들은 실험실적으로 확인하였다. 운전 변수 가운데 유리의 점도와 전기 전도도는 세 후보유리 모두 적정운전 범위값 내에 만족하였으며 밀도, 화학적 견고성, 상안정성 등 고화체의 품질 또한 우수하였다. 개발한 유리 조성 연구를 바탕으로 폐수지, 잡고체, 혼합폐기물을 유리화 할 경우 감용비는 각각 21, 89, 75로 평가되었다.