SnO₂/TiO₂후막형 습도센서의 제조 및 특성

이건동,이재현,박효덕,이덕동,최흥문 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

SnO_(2) doped with TiO_(2) and other activating agents, is used as a raw material to prepare humidity sensors. SnO_(2) is an n-type semiconductor whose resistance is described as a function of relative humidity. SnO_(2)/TiO_(2) thick film humidity sensors have been fabricated by using typical silk screen printing techniques. The humidity sensitivity of SnO_(2)/TiO_(2) thick film has been investigated. And the sensing characteristics of the fabricated SnO_(2)/TiO_(2) sensors such as resistance change and response time, has been investigated from R.H.20 % to 90 %. Experimental results show that the impedance-humidity characteristics of the humidity sensors depend on the microstructure of surface roughness and pore size distribution.

빌트인 모터를 이용한 2축 제어 미세 가공기 개발

김건희,김효식,양순철,이상용,국명호,이선규,김윤중,홍권희 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

This paper describes development of low cost precision machine that has combined the Build-in Motor with a vacuum chuck. This study mainly aims to find out a cutting condition for maintaining optimum surface condition and to examine cutting characteristics of the precision machine that is equipped by diamond bites. The cutting materials is Al alloy. Several experiments were carried out to find out the main factors that affect the surface roughness such as principal axis RPM(rotation per minute), feeding speed, and cutting depth. As a result, we obtain The optimum cutting condition of the developed precision machine.

Synergistic Effects of a Multifunctional Graphene Based Interlayer on Electrochemical Behavior and Structural Stability

Lee, Young-Woo,An, Geon-Hyoung,Kim, Byung-Sung,Hong, John,Pak, Sangyeon,Lee, Eun-Hwan,Cho, Yuljae,Lee, Juwon,Giraud, Paul,Cha, Seung Nam,Ahn, Hyo-Jin,Sohn, Jung Inn,Kim, Jong Min American Chemical Society 2016 ACS APPLIED MATERIALS & INTERFACES Vol.8 No.27

<P>The ability to rationally design and manipulate the interfacial structure in lithium ion batteries (LIBs) is of utmost technological importance for achieving desired performance requirements as it provides synergistic effects to the electrochemical properties and cycling stability of electrode materials. However, despite considerable efforts and progress made in recent years through the interface engineering based on active electrode materials, relatively little attention has been devoted to address the physical aspects of the interface and interfacial layer between the anode materials layer and the current collector. Here, we propose and successfully grow unique graphene directly on a Cu current collector as an ideal interfacial layer using the modified chemical vapor deposition (CVD). The anode with an engineered graphene interlayer exhibits remarkably improved electrochemical performances, such as large reversible specific capacity (921.4 mAh g(-1) at current density of 200 mA CI), excellent Coulombic efficiency (close to approximately 96%), and superior cycling capacity retention and rate properties compared to the bare Cu. These excellentelectrochemical features are discussed in terms of multiple beneficial effects of graphene on interfacial stability and adhesion between the anode and the collector, oxidation or corrosion resistance of the graphene grown Cu current collector, and electrical contact conductance during the charge/discharge process.</P>

Optical Sensing Properties of ZnO Nanoparticles Prepared by Spray Pyrolysis

Lee, Geon Joon,Choi, Eun Ha,Nam, Sang-Hun,Lee, Jin Su,Boo, Jin-Hyo,Oh, Si Duck,Choi, Suk-Ho,Cho, Jun-Haeng,Yoon, Moon-Young American Scientific Publishers 2019 Journal of Nanoscience and Nanotechnology Vol.19 No.2

Changes in Large Crabgrass Growth and Herbicide Efficacy Caused by Increasing Temperatures

Hyo Jin Lee,Hyun Hwa Park,Ye Geon Kim,Do Jin Lee,Yong In Kuk 한국잡초학회 2023 한국잡초학회 별책(학술대회 초록집) Vol.43 No.1

Effects of Increasing Air Temperatures and CO₂ Concentrations on Weed Growth and Herbicide Efficacy

Hyo Jin Lee,Hyun Hwa Park,Ye Geon Kim,Yeon Hu Woo,Do Jin Lee,Yong In Kuk 한국잡초학회 2023 한국잡초학회 별책(학술대회 초록집) Vol.43 No.2

Comparision of antioxidant and anti-inflammatory activities of enzyme assisted hydrolysate from Ecklonia maxima blades and stipe

Lee, Hyo-Geun,Je, Jun-Geon,Hwang, Jin,Jayawardena, Thilina U.,Nagahawatta, D.P.,Lu, Yu An,Kim, Hyun-Soo,Kang, Min-Cheol,Lee, Dae-Sung,Jeon, You-Jin The Korean Society of Fisheries and Aquatic Scienc 2021 Fisheries and Aquatic Sciences Vol.24 No.5

Marine brown seaweeds are a source of functional ingredients with various biological properties. They have been used in the food and functional food industries. Brown seaweeds are divided into three parts of blades, stipe, and root. Normally seaweed blades were used as raw materials for biological research. However, there are limited uses on stipes of Ecklonia maxima (E. maxima) depending on the physicochemical, nutritional, and biological properties. Besides, the comparative studies of two structures of E. maxima, blades and stipe didn't discover previously. This study aimed to compare the potent antioxidant and anti-inflammatory activities of the two structures of E. maxima, blades and stipe in vitro studies to increase the utilization of the two structures of E. maxima. The enzyme-assisted hydrolysate from E. maxima showed significant antioxidant and anti-inflammatory activities. Among them, celluclast-assisted hydrolysate from E. maxima blades (EMBC) and viscozyme-assisted hydrolysate from E. maxima stipe (EMSV) expressed significant protection on hydrogen peroxide-induced oxidative stress. Moreover, EMBC and EMSV treatment remarkably reduced nitric oxide production by downregulation of pro-inflammatory cytokine expressions in lipopolysaccharide-stimulated Raw 264.7 cells. Especially EMBC showed strong inhibition on pro-inflammatory cytokine production compared to EMSV. Taken together research findings suggest that EMBC and EMSV possessed potent antioxidant and anti-inflammatory properties and may be utilized as functional ingredients in the food and functional food sectors.

대기온도와 CO₂ 농도 증가에 따른 우점잡초 깨풀의 제초제 약효 및 콩 약해 변화§

이효진(Hyo-Jin Lee),박현화(Hyun-Hwa Park),김예건(Ye-Geon Kim),이도진(Do-Jin Lee),국용인(Yong-In Kuk) 한국작물학회 2023 한국작물학회지 Vol.68 No.3

본 연구의 목적은 기후변화에 따른 이산화탄소와 온도의변화에 따른 콩밭 우점잡초 깨풀의 생장과 주요 4종의 경엽처리 제초제와 4종의 토양처리 제초제에 대한 약효와 콩의 약해를 평가하여 잡초 관리 방안을 마련하는 데 있다. 생장상과 온실상 조건하에서 온도가 증가할수록 깨풀의 초장및 생체중은 증가하였다. 이산화탄소 농도에 따른 Fv/Fm, ETR, 초장, 엽면적 및 지상부 생체중은 400 ppm보다 800 ppm에서 더 높았다. 깨풀에 대한 경엽처리제 glufosinate 약효의 경우 생장상 조건의 20°C 및 25°C보다 30°C에서 온실상조건의 21°C 및 25°C보다 29°C에서 감소하였다. 반대로mecoprop의 경우 생장상 조건의 30°C에 비해 20°C에서 온실상 조건의 29°C에 비해 21°C에서 약효가 감소하였다. 경엽처리제 glyphosate의 경우 온실상 조건하에서는 25°C와29°C에 비해 21°C에서 약효가 감소하였다. Bentazone을 생장상 조건하에서 1/2량 처리하였을 때 25°C와 30°C에 비해 20°C에서 약효가 감소하였다. 그러나 온실상 조건하에서는 21°C와 25°C에 비해 29°C에서 약효가 감소하였다. 깨풀에 대한 토양처리제 경우 생장상과 온실상 조건하에서metolachlor와 ethalfluraline의 약효는 온도가 상대적으로 높은 조건하에서 약효가 높았다. 그러나 linuron의 경우는 생장상과 온실상의 온도에 상관없이 약효차이가 없었다. Alachlor 의 경우 온실상 조건하에서 19°C와 23°C에 비해 27°C에서약효가 감소하였다. 경엽처리 제초제 4종을 표준량으로 깨풀에 처리하였을 때 이산화탄소농도에 따른 차이는 없었다. 그러나 깨풀에 glyphosate 1/4량 처리하였을 때 이산화탄소농도가 400 ppm보다 800 ppm일 때 약효는 감소하였다. 반대로 bentazone를 1/4량 처리하였을 때 이산화탄소 농도가400 ppm보다 800 ppm일 때 약효는 증가하였다. Glufosinate 은 처리약량에 상관없이 이산화탄소 농도에 따른 유의적인 차이가 없었다. 토양처리 제초제 ethalfluralin을 1/4량 처리하였을 때는 이산화탄소의 농도가 800 ppm일 때 약효가더 높았다. 그 외의 제초제의 경우 이산화탄소 농도와 상관없이 깨풀의 약효에는 차이가 없었다. 콩에 토양처리 제초제를 표준량과 표준량의 2배량을 처리하였을 때 온도와 이산화탄소 농도에 따른 약해는 유의적인 차이가 없었다. 따라서 온도와 이산화탄소 농도 증가에 기인하여 일부 제초제에 대한 잡초 약효 차이가 있어 기후변화에 의한 새로운잡초 관리 방법을 개발해야 할 것으로 판단된다. The purpose of this study was to improve weed management systems under varying carbon dioxide concentrations and temperatures by evaluating the growth of Acalypha australis and observing the efficacy of four foliar and four soil herbicides, as well as measuring phytotoxicity in soybean crops treated with these herbicides. In both growth chamber and greenhouse conditions, plant height and shoot fresh weight of Acalypha australis increased as temperature increased. The variable to maximum fluorescence ratio (Fv/Fm), relative electron transport rate (ETR), plant height, leaf area, and shoot fresh weight of Acalypha australis were higher at carbon dioxide concentrations of 800 ppm than at 400 ppm. The efficacy of a foliar herbicide, glufosinate, on Acalypha australis was lower at 30°C than at 20°C and 25°C in the growth chamber condition and was also lower at 29°C than at 21°C and 25°C in greenhouse conditions. In contrast, mecoprop efficacy on Acalypha australis was lower at 20°C and 25°C than at 30°C in growth chamber conditions and lower at 21°C and 25°C than at 29°C in greenhouse conditions. Glyphosate efficacy was lower at 21°C than at 25°C and 29°C under greenhouse conditions. With soil herbicides, metolachlor and ethalfluraline, efficacies were higher at relatively high temperatures under both growth chamber and greenhouse conditions. However, in the case of linuron, the difference in efficacy was not observed under varying temperatures in both growth chamber and greenhouse conditions. When ¼ of the recommended glyphosate rates were applied to Acalypha australis, efficacy was lower under 800 ppm carbon dioxide concentrations than under 400 ppm. In contrast, when ¼ of the recommended rate of bentazone was applied to Acalypha australis, efficacy was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. Despite application rates, glufosinate efficacy differed insignificantly under different carbon dioxide concentrations. When applied at ¼ of the recommended rate, the efficacy of ethalfuralin was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. However, efficacies of other herbicides were not different despite varying carbon dioxide concentrations. Soybean phytotoxicity in crops treated with the recommended rate and twice the recommended rate of soil herbicides was not significantly different regardless of temperature and carbon dioxide concentrations. Overall, weed efficacy of some herbicides decreased in response to different temperatures and carbon dioxide concentrations. Therefore, new weed management methods are required to ensure high rates of weed control in conditions affected by climate change.

EBUS-centred versus EUS-centred mediastinal staging in lung cancer: a randomised controlled trial

Kang, Hyo Jae,Hwangbo, Bin,Lee, Geon-Kook,Nam, Byung-Ho,Lee, Hyun-Sung,Kim, Moon Soo,Lee, Jong Mog,Zo, Jae Ill,Lee, Hee Seok,Han, Ji-Youn BMJ Publishing Group Ltd 2014 Thorax Vol.69 No.3

<P><B>Background</B></P><P>The impact of procedure sequence and primary procedure has not been studied in the combined application of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in lung cancer staging.</P><P><B>Methods</B></P><P>In a randomised controlled trial, 160 patients with histologically confirmed or strongly suspected potentially operable non-small cell lung cancer were enrolled (Group A, n=80, EBUS-centred; Group B, n=80, EUS-centred). EBUS-TBNA and EUS-FNA with an ultrasound bronchoscope were used as the first procedures in Groups A and B, respectively, and secondary procedures (EUS-FNA in Group A, EBUS-TBNA in Group B) were added.</P><P><B>Results</B></P><P>Diagnostic values were evaluated in 148 patients (74 in each group). In Groups A and B the diagnostic accuracy (93.2% (95% CI 87.5% to 99.0%) vs 97.3% (95% CI 93.6% to 101.0%), p=0.245) and sensitivity (85.3% (95% CI 68.9% to 95.0%) vs 92.0% (95% CI 74.0% to 99.0%), p=0.431) in detecting mediastinal metastasis were not statistically different. In Group A, adding EUS-FNA to EBUS-TBNA did not significantly increase the accuracy (from 91.9% to 93.2%, p=0.754) or sensitivity (from 82.4% to 85.3%, p=0.742). In group B, adding EBUS-TBNA to EUS-FNA increased the accuracy (from 86.5% to 97.3%, p=0.016) and sensitivity (from 60.0% to 92.0%, p=0.008). There were no intergroup differences in procedure time, cardiorespiratory parameters during procedures, complications or patient satisfaction.</P><P><B>Conclusions</B></P><P>Using a combination of EBUS-TBNA and EUS-FNA in mediastinal staging, we found that diagnostic values and patient satisfaction were not different between the EBUS-centred and EUS-centred groups. However, the necessity for EBUS-TBNA following EUS suggests that EBUS-TBNA is a better primary procedure in endoscopic mediastinal staging of potentially operable lung cancer.</P><P><B>Trial Registration number</B></P><P>ClinicalTrials.gov number NCT01385111.</P>

방송대 간호학생의 교육요구 및 효율적 네트워크 구성에 관한 조사연구

이상미(Lee, Sang Mi),김영임(Kim, Young Im),이선옥(Lee, Sun Ock),근효근(Geon, Hyo Geon) 한국간호교육학회 1998 한국간호교육학회지 Vol.4 No.2