Layer-by-Layer Doping of Few-Layer Graphene Film

Gü,neş,, Fethullah,Shin, Hyeon-Jin,Biswas, Chandan,Han, Gang Hee,Kim, Eun Sung,Chae, Seung Jin,Choi, Jae-Young,Lee, Young Hee American Chemical Society 2010 ACS NANO Vol.4 No.8

<P>We propose a new method of layer-by-layer (LbL) doping of thin graphene films. Large area monolayer graphene was synthesized on Cu foil by using the chemical vapor deposition method. Each layer was transferred on a polyethylene terephthalate substrate followed by a salt-solution casting, where the whole process was repeated several times to get LbL-doped thin layers. With this method, sheet resistance was significantly decreased up to ∼80% with little sacrifice in transmittance. Unlike samples fabricated by topmost layer doping, our sample shows better environmental stability due to the presence of dominant neutral Au atoms on the surface which was confirmed by angle-resolved X-ray photoelectron spectroscopy. The sheet resistance of the LbL-doped four-layer graphene (11 × 11 cm<SUP>2</SUP>) was 54 Ω/sq at 85% transmittance, which meets the technical target for industrial applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2010/ancac3.2010.4.issue-8/nn1008808/production/images/medium/nn-2010-008808_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn1008808'>ACS Electronic Supporting Info</A></P>

Introduction and application of a composite insect trap for the National Ecosystem Survey of Korea

Han Yong‐Gu,Hong Eui jeong,Kim Do‐Sung,Kim Chulgoo,Cha Jin Yeol 한국곤충학회 2020 Entomological Research Vol.50 No.10

This study aimed to establish the best applicable method for the National Ecosystem Survey (NES) guidelines by (i) verifying the efficiency of an insect trap that combined the Malaise trap, flight intercept trap, and pitfall trap (MFP trap) as part of the improvement for the terrestrial insect field in the fifth NES, and (ii) comparing the result with the currently used Malaise trap and pitfall trap (MP traps). We found that the efficiency of attaining species diversity was much higher with the added flight intercept trap function than the current Malaise trap alone for flying insect collection. For collecting ground insects, the efficiency of attaining species diversity of the pitfall trap from the MFP trap was lower than that from the MP trap. Besides, the Malaise trap of the MP trap showed superior efficiency than that of the MFP trap in species diversity. The results suggested that modification, supplementation, and re‐testing should be performed by analyzing various factors such as the trap material, barrier size, capturing container inlet, and mesh size, with consideration of the design of the current Malaise trap. Therefore, in survey‐based research, which aims at identifying insects species diversity and inhabiting status—such as the NES, it is necessary to introduce the MFP trap with the flight intercept trap function added to the Malaise trap function, and for the pitfall trap function of the MFP trap, it can be operated as a separate trap from the MFP trap.

전기화학적 방법을 이용한 수소제거에 관한 연구

박창규,김재홍,김정구,안승호,박진석,김종성,진태은 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.3

Hydrogen embrittlement (HE) mitigation on the low alloy steel was studied using electrochemical technique. This method can be applied to reduce HE susceptibility. Hydrogen induced cracking (HIC) characteristics of the low alloy steel was investigated in aerated and deaerated borate buffer solution (0.3M H₃BO₃ + 0.074M N₂B_(4)O_(7), pH 8.4). The electrochemical properties of the low alloy steel showed passive behavior in this environment. By performing galvanostatic and potentiostatic test, hydrogen was charged and discharged to specimens respectively. By applying the potential of +630 mV_(SCE), the accumulated hydrogen was eliminated electrochemically. A specimen discharged for 24h indicated the efficiency of the hydrogen discharge up to 99.9%. Slow strain rate tests (SSRT) results showed that a specimen with higher hydrogen concentration revealed inferior mechanical properties such as shorter time to fracture, lower elongation, ultimate tensile strength and yield strength values. Furthermore, SEM fractographs revealed that the higher the hydrogen concentration is, the more probable the features of brittle fracture are. (Received July 26, 2004)

위전절제술 후 Kim 's Tie 부근 공장에 국소 재발한 위암환자 1예

배병구,서병조,유항종,강윤경,김진복,Bae Byung-Gu,Suh Byoung-Jo,Yu Hang-Jong,Kang Yun-Kyung,Kim Jin-Pok 대한위암학회 2005 대한위암학회지 Vol.5 No.1

위암은 국내에서 발생 빈도가 가장 높은 암으로서 근치적 절제술 및 확대 영역 림프절 절제술의 도입과 더불어 술후 보조 항암화학요법 및 면역요법 등의 이용으로 최근 치료성적의 향상을 보이고 있다. 그러나 수술적 치료를 포함한 치료법의 발전에도 불구하고 다양한 형태의 재발을 경험하게 되고, 대부분의 재발은 3년 이내에 일어난다. 재발양상으로는 크게 국소재발, 원격재발, 복막재발 등이 있으며, 여러 가지 재발양상이 한꺼번에 보이는 경우도 있다. 이 중 국소재발의 호발 부위로는 림프절($48\%$), 문합부($32\%$, 잔존 위($20\%$)의 순으로 보고되고 있다. 증례: 51세의 여자 환자로 1999년 10월 진행성 위암으로 근치적 위전절제술을 시행 받았고, 당시 병기는 T3N1M0(IIIa,AJCC 1997)이었다. 수술 후 10회의 보조적 정맥 주사용 항암화학요법 및 경구용 항암화학요법을 2년간 실시하였고, 외래를 통한 추적검사상 약 5년간 재발을 보이지 않았으나 2004년 9월 시행한 내시경상 Kim's tie 부근공장에서 궤양성 병변을 발견하고 조직검사를 시행, 병리학적으로 낮은 분화도를 보이는 인환 세포암종 형태의 위선암 재발로 진단하고 수술을 시행하였다. 수술 방법은 Kim's tie 위치를 포함해 근위부 6.5 cm, 원위부 4 cm의 절제연을 두고 공장부분 절제술을 시행하였다. 수술 당시 다른 복부장기로 전이는 없었으며 전이성 복수도 없었다. 수술 후 별다른 합병증 없이 회복하였으며 보조 항암화학요법 제제로써 TS-1을 사용하며 외래 통한 추적검사 중이다. Despite improvements in the surgical treatment of gastric adenocarcinomas, the recurrence rates remain high in patients with advanced-stage disease. Most of the recurrence occurs within 3 years of the surgical resection, and nearly $90\%$ of the patients with recurrence die within 2 years of the diagnosis of recurrence. A recent study analyzed recurrence patterns for patients who had undergone a potentially curative gastrectomy. For those patients, $33\%$ of the recurrences involved locoregional sites, $44\%$ the peritoneum, and $38\%$ distant sites. A 51-year-old female patient was diagnosed with stomach cancer and underwent a total gastrectomy with D2 lymph node dissection during Oct. 1999. The pathologic report indicated a T3N1M0 tumor. We performed immunochemotherapy for 2 years with regular follow up. A gastrofiberscopic examination done during sep. 2004, cancer recurrence was found at the Kim's tie site of the jejunual loop. We did an abdominal exploration and a segmental resection of cancer site with pathologically negative resection margins. After the operation, we started secondary chemotherapy with TS-1.

3차원 그래픽스를 이용한 실시간 로봇 모니터링 및 예측

김진구,정다운,전재욱 成均館大學校 科學技術硏究所 1997 論文集 Vol.48 No.1

In industrial automation lines, the main method to transfer information,, about robots is using some digital I/O in robot systems. Through these digital I/O, the state of each robot task is monitored whether it has been performed correctly or not. But this method can only communicate some informations among predefined states of each robot task and do no informations about other states during each robot task. In order to monitor detailed states of robot systems during each task, robot systems have used a video display or a graphics system. Some researches have used graphics systems to make real-time display and replay in addition to off-line simulation. This paper proposes a technique to monitor real time robot motions and to predict robot motions by using 3-d graphics. A graphics system is used to represent a virtual robot so that some c ordination between a real robot and this virtual robot can be achieved. With this coordination, monitoring and prediction of robot, motions will be performed.

PECVD법으로 증착된 전자소자용 thiophene 박막의 전기화학적 신뢰성에 관한 연구

김정구,박진택,최윤석,부진효,유용재 대한금속재료학회 2003 대한금속·재료학회지 Vol.41 No.6

The corrosion failure of electronic devices has been a major reliability concern lately. This failure is an ongoing concern because of miniaturization of integrated circuits(IC) and the increased use of polymers in electronic packaging. In this paper plasma-polymerized thiophene films were considered as a possible candidate for an interlayer dielectric for multilever metallization of ultra large scale integrated (ULSI) semiconductor devices. The protective ability of above films as a function RF power in an 3.5 wt.% NaCl solution was examined by electrochemical methods and contact angle measurement. The protective efficiency of the film increased with increasing RF power, which induced the higher degree of cross-linking and hydrophobicity of the films.

전자토모그래피의 정량적 분석에서 대물렌즈 조리개의 영향

김진규,이상희,권희석,정종만,정원구,이수정,주형태,김윤중 韓國電子顯微鏡學會 2008 Applied microscopy Vol.38 No.4

Electron tomography의 정량적 분석을 위해서 대물렌즈 조리개가 투과빔의 강도에 미치는 영향을 평가하였다. Electron tomography에 도입되는 Beer’s law의 올바른 적용을 위해서는 투과빔은 시료의 기울기에 따른 mass thickness의 변화에 의한 효과만을 반영해야 한다. 그러므로 빔 경로상의 대물렌즈 조리개, 홀더 등에 의한 다른 효과는 제거되어야 한다. 본 연구에서는 대물렌즈 조리개의 cut-off 효과를 120 kV TEM과 Quantifoil holey 카본 시료를 이용하여 상세히 평가하였다. 대물렌즈 조리개를 사용하지 않은 경우와 비교할 때, 30 μm 크기의 대물렌즈 조리개를 통과한 투과전자빔의 강도는 약 16.7%의 감소가 일어난다. 또한 55˚이상의 고경사각 기울기에서는 대물렌즈 조리개의 cut-off 효과에 의해 14.2%의 강도 감소가 추가적으로 발생함을 알 수 있었다. Electron tomography에서 정량적 분석을 위해서는 이러한 대물렌즈 조리개의 영향을 고려해야만 한다. 또한 Beer’s law의 올바른 적용을 위해서는 일련의 기울기에 따른 2차원적 영상은 가능하면 대물렌즈 조리개를 사용하지 않은 상태에서 획득하는 것이 바람직하다. We have evaluated the effects of experimental factors on transmitted electron beam intensities for quantitative analysis in electron tomography. For the correct application of Beer’s law in electron tomography, the transmitted beam intensity should reflect the net effect of mass properties on beam path. So, the any other effects of the objective aperture and the specimen holder on beam path should be removed. The cut-off effects of objective aperture were examined using Quantifoil holey carbon film and a transmission electron microscope operated at 120 kV. The transmitted beam intensities with 30 μm objective aperture dropped about 16.7% compared to electron beam intensities without the objective aperture. Also, the additional losses of about 14.2% at high tilt angles were occurred by cut-off effects of the objective apertures. For the precise quantitative analysis in electron tomography, the effect of the objective aperture on transmitted electron beam intensities should be considered. It is desirable that 2-D tilt series images are obtained without the objective aperture for correct application of Bee’s law.

P300 사건관련전위를 통한 대뇌의 피칭운동 연계성 분석

김진구 한국스포츠심리학회 2003 한국스포츠심리학회지 Vol.14 No.2

ERP의 구성요소인 P300은 자극이 제시된 후 약 300msec 후에 나타나는 양(+)의 전압으로 P300의 잠재기와 진폭은 인지정보처리과정을 설명하는데 사용된다. 운동학습제어 분야에서는 ERP와 운동수행과의 관계를 다룬 연구는 거의 없는 실정이다. 따라서 본 연구에서는 자극이 뇌에 유입되었을 때 나타나는 P300을 여구하여 투수가 던진 볼을 타자가 선구할 때 유발되는 인지정보처리 과정을 연구했다. 피험자는 대학교에 재학 중인 20-23세의 남학생 42명을 대상으로 하였다. 실험에 사용된 자극은 "oddball"과제, 즉 투수가 던진 다섯 가지 구질(안쪽 직구, 바깥쪽 직구, 커브 볼, 슬라이드, 체인지업)을 비디오카메라로 촬영하여, 동영상을 디지털로 전환시킨 뒤 각 구질이 3.5초간 지속되도록 편집해 사용하였다. 목표자극은 커브 볼이며 제시빈도는 20%(150개중 30개)이고, 표준자극은 바깥쪽 직구로 제시빈도는 80% (150개 중 120개)였다. EEG는 목표자극인 커브볼에 대한 반응 중 정반응(hit)한 것만을 사용하였으며 EOG가 기준 값보다 높게 나온 시행이나, 잡파가 섞인 EEG는 평균화 작업을 통해 소거했다. 실험설계는 과제(2) × 영역(4) × 자극(2)에 대해 3원 혼합 분산분석을 실시하였다. 종속변수는 ERP의 진폭과 잠재기였다. 본 연구의 결과는 투수의 투구 구질에 따라 타자의 정보처리과정이 다르게 진행된다는 것을 보여주었다. 즉 목표자극에서 P300의 진폭이 표준자극에서보다 큰 것으로 나타났다. 과제의 난이도에 따라서는 진폭의 높이에 차이가 없는 것으로 나타났다. 그러나 본 연구의 결과는 과제의 난이도에 따라서 P300이 변화하지 않는다는 바닥효과가정(floor effect assuption)을 지지한다. P-300 in an event related brain potential that has attracted attention as an indicator of mental processes such as cognitive functioning and information processing. The P300 occurs approximately 300-1000 ms after simulus onset and measures immediate reaction of the brain, thus it could be a useful tool in understanding the pattern of information processing regarding to task relevant stimuli. Therefore, the study examined P300 event related brain potentials in response to pitching to determine information processing such as selective attention and decision making. Forty two university students participated in this experiment. Stimuli used for this study were five different types of pitches (e.g., curve ball 112km/h, inside fastball 135km/h, outside fastball 134km/h, change-up 126km/h, and slider 121km/h) thrown by a professional pitcher to examine the latency and amplitude of P300 while participants reacted to filmed action. The pitched simuli were filmed using a digital handy camera and each stimulus was edited to equal the amount of time(3.5s) presented(from pitcher's wind-up to finishing motion) on a monitor in random order. The ratios(frequency) of goal stimulus(i.e., curveball and standard stimul(i.e., inside fastball, outside fastball, slider, chang-up) presented were 20%(30 out of 150) and 80%(120 out of 150) pitches respectively. A 2(Groups)×4(Areas)×2(Stimuli) ANOVAs were used to analyze EEG data, Dependent measures were the latencies and amplitude of ERP on each electrode site. The results indicated that the amplitudes of P300 were greater in the goal stimulus than in the standard stimulus. The results also revealed that the amplitudes of P300 were different among O1, Fz, Pz and Cz. the findings support the previous findings (floor effect assumption) that in general, P300 was not influenced by task difficulty.

옥수수 播種期와 地上部形質에 관한 硏究

金鎭淇,崔京求,白南赫,陳星桂 全北大學校 1982 論文集 Vol.24 No.-

全北 平野地인 裡里地方에서 옥수수의 播種期와 地上部生育 및 種實收量과의 관계를 調査하여 다음과 같은 결과를 얻었다. 1. 播種期의 早晩이 莖葉의 生育 및 種實收量에 크게 영향을 끼치며 播種이 늦어질수록 出雄, 出絲, 生育日數가 짧아지고 地上部生育은 떨어지는 경향이다. 2. 莖葉生育은 4月 20日 播種을 基點으로, 種實收量은 5月 5日 播種을 基點으로 各各 減少되었다. 3. 地上部諸形質과 種實收量간에는 高度의 正의 相關이 인정되며 種實增收를 위하여는 莖葉生育은 크게 할 필요가 있다. Some results were gained through the experiment that was carried out with a single cross cultivar, Suweon 19, of maize (Zea mays L.) in Iri, the Jeonbug plain area, in 1980, to check relationships between growth characters at different sowing dates. 1. The foliage growth and grain yield were greatly influenced with planting season. The number of days to tasseling, silking, or maturing shortened and the growth of maize decreased as sowing was delayed. 2. The threshold sowing date for foliage production seemed to be April 20 and that for grain yield, May 5. 3. Highly significant positive correlation existed between vegetative growth and grain yield. This may mean that increasing vegetative growth is prerequisite to better grain yield.

摩擦電氣에 關한 實驗器具 開發

金容福,姜鎭求 공주대학교 사범대학 과학교육연구소 1992 과학교육연구 Vol.23 No.1

As a result, three kinds of new and effective laboratory apparatus were developed. They are as follows: 1. THE APPARATUS FOR MEASURING THE QUANTITY OF FRICTIONAL ELECTRICITY This is the device that can be used for measuring the quantity of electricity of the objects with electric charge. Using the apparatus, we can easily measure the quantity of frictional electric charge in unit area (coulomb/㎠). 2. THE APPARATUS FOR MEASURING THE ELECTRIC DISCHARGE BY THE PROBE This is the device theat can oberve the electric discharge which occurs between the objects with electric charge and the probe. Using the apparatus, we can understand that lightning strikes are electrical phenomena, and that disasters from them can be prevented or avoided. 3. THE APPARATUS FOR MEASURING THE DISTRIBUTION OF ELECTRIC CHARGE. This is the device that can be used for measuring the distribution of electric charge, especially of the frictional electricity distribution on insulators.