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Graphoepitaxy법을 이용하여 SiO$_2$ 기판 위에 제작한 ZnO 박막의 특성에 관한 연구 (Graphoepitaxy of ZnO thin films by Zn evaporation)

  • 김광희;최석철;이태훈;정진우;박승환;정미나;정명훈;양민;;장지호
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.1026-1029
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    • 2005
  • Grating 이 형성된 SiO$_2$ 기판상에 ZnO 박막을 graphoepitaxy 법으로 형성시킬 것을 제안하고 그 가능성을 고찰하였다. Si(100) 기판상에 노광작업(photolithograpy)을 이용하여 요철구조를 형성시킨 다음 자연산화를 시켜서 SiO$_2$ 기판을 제작하였고, 제작된 요철구조 위에 열증착 법으로 Zn 를 증착 시킨 후 이를 산화 시켜서 ZnO 박막을 형성 시켰다. 또한 열처리에 의한 결정성의 변화를 관찰하기 위하여 700 ${\sim}$ 900 $^{\circ}C$에서 열처리를 하였다. 제작된 시료는 Atomic Force Microscopy (AFM)로 표면을 관찰하였으며, Photoluminescence (PL) 을 이용하여 결정성의 변화를 관찰하였다.

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단방향 이동 Ad Hoc 망에서의 다중경로를 이용한 QoS 라우팅 프로토콜 (QoS Routing Protocol using multi path in Unidirectional Mobile Ad Hoc Networks)

  • 강경인;박경배;유충렬;정찬혁;이광배;김현욱
    • 정보처리학회논문지C
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    • 제9C권6호
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    • pp.935-944
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    • 2002
  • 이동 애드 혹(Ad hoc)네트워크란 노드의 이동에 따라 시시각각 변하는 무선 링크로 연결되어진 여러 개의 단말기들로 구성된 있는 자치분산 네트워크를 의미한다. 지금 까지 이동 ad hoc 네트워크에서의 통신은 Voice(음성)와 Data(데이터)통신을 제공하는 Best effort(최선형)서비스를 제공하는 라우팅 프로토콜만이 고려되어왔기 때문에 이동 네트워크를 사용하는 사용자가 많은 양의 자원을 차지하는 VOD(Video On Demand)와 같은 멀티미디어 Data를 보다 빠르고 정확하고 신속하게 전송하기 위해서는 기존의 Best effort 방식으로 전송되는 라우팅 프로토콜에는 많은 한계가 있었다(1). 따라서 본 논문에서는 성능평가를 위해 단방향 환경 하에서의 QoS(Qualify of Service)를 고려한 제안한 알고리즘을 적용하였다. 성능평가 카네기 멜론 과 버클리대학에서 만든 Ns-2를 사용하여 최선형 서비스(Best Effort)와 비교하여 QoS 서비스의 수신율 상승과 평균 경로설정 시간의 감소, 네트워크 부하 감소를 얻을수 있었다.

정제된 의미정보와 시소러스를 이용한 동형이의어 분별 시스템 (A Korean Homonym Disambiguation System Using Refined Semantic Information and Thesaurus)

  • 김준수;옥철영
    • 정보처리학회논문지B
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    • 제12B권7호
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    • pp.829-840
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    • 2005
  • 단어 의미 중의성 해소는 자연언어처리 분야에 매우 중요한 부분이다. 본 논문에서는 사전 뜻풀이 특성을 이용해 기존의 의미정보를 정제하고 유용한 정보인 확률정보, 거리정보 및 격정보 등을 추가한 WSD 모델을 제안하였으며, 사전을 기반으로 구축된 "울산대학교 어휘 지능망(UOU-Word Intelligent Network: U-WIN)" 상의 단어 계층적 구조(시소러스)를 이용하여 의미정보의 자료 부족 문제를 해소하는 모델을 제시하였"다. "21세기 세종 계획"에서 제공하는 150만 어절 규모의 의미 태그 말뭉치를 대상으로 한 실험에서 최다 빈도 의미 결정(Maximum Frequence Class, MFC, 정확률 베이스라인)에 비해 $18.97\%$(명사 $21.73\%$, 동사 $17.11\%$) 정확률 향상을 보였으며, 기존의 확률 가중치와 어절 거리 가중치를 이용한 모델에 비해서는 $10.49\%$(명사 $8.84\%$, 동사 $11.51\%$)의 정확률 향상되었다. 또한 시소러스를 사용하지 않고 확률정보, 거리정보, 격정보 만을 이용한 모델에 비해 $6.12\%$(명사 $5.29\%$, 동사 $6.64\%$) 높은 정확률을 보였다.

작물학 분야 프로테오믹스의 응용과 전망 (Application and perspectives of proteomics in crop science fields)

  • 우선희
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2004년도 춘계 학술대회지
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    • pp.12-27
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    • 2004
  • Thanks to spectacular advances in the techniques for identifying proteins separated by two-dimensional electrophoresis and in methods for large-scale analysis of proteome variations, proteomics is becoming an essential methodology in various fields of plant sciences. Plant proteomics would be most useful when combined with other functional genomics tools and approaches. A combination of microarray and proteomics analysis will indicate whether gene regulation is controlled at the level of transcription or translation and protein accumulation. In this review, we described the catalogues of the rice proteome which were constructed in our program, and functional characterization of some of these proteins was discussed. Mass-spectrometry is a most prevalent technique to identify rapidly a large of proteins in proteome analysis. However, the conventional Western blotting/sequencing technique us still used in many laboratories. As a first step to efficiently construct protein data-file in proteome analysis of major cereals, we have analyzed the N-terminal sequences of 100 rice embryo proteins and 70 wheat spike proteins separated by two-dimensional electrophoresis. Edman degradation revealed the N-terminal peptide sequences of only 31 rice proteins and 47 wheat proteins, suggesting that the rest of separated protein spots are N-terminally blocked. To efficiently determine the internal sequence of blocked proteins, we have developed a modified Cleveland peptide mapping method. Using this above method, the internal sequences of all blocked rice proteins (i. e., 69 proteins) were determined. Among these 100 rice proteins, thirty were proteins for which homologous sequence in the rice genome database could be identified. However, the rest of the proteins lacked homologous proteins. This appears to be consistent with the fact that about 30% of total rice cDNA have been deposited in the database. Also, the major proteins involved in the growth and development of rice can be identified using the proteome approach. Some of these proteins, including a calcium-binding protein that fumed out to be calreticulin, gibberellin-binding protein, which is ribulose-1,5-bisphosphate carboxylase/oxygenase activate in rice, and leginsulin-binding protein in soybean have functions in the signal transduction pathway. Proteomics is well suited not only to determine interaction between pairs of proteins, but also to identify multisubunit complexes. Currently, a protein-protein interaction database for plant proteins (http://genome .c .kanazawa-u.ac.jp/Y2H)could be a very useful tool for the plant research community. Recently, we are separated proteins from grain filling and seed maturation in rice to perform ESI-Q-TOF/MS and MALDI-TOF/MS. This experiment shows a possibility to easily and rapidly identify a number of 2-DE separated proteins of rice by ESI-Q-TOF/MS and MALDI-TOF/MS. Therefore, the Information thus obtained from the plant proteome would be helpful in predicting the function of the unknown proteins and would be useful in the plant molecular breeding. Also, information from our study could provide a venue to plant breeder and molecular biologist to design their research strategies precisely.

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전문대학 치위생과 학생의 학과선택 및 실습실에 대한 만족도 (A Study on Post-Admission Satisfaction Level among Dental Hygiene Students in Colleges)

  • 박일순;이경희
    • 한국치위생학회지
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    • 제6권4호
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    • pp.349-359
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    • 2006
  • The purpose of this study was to help improve the quality of education to keep up with fast-changing environments in educating sector. Relevant literature and data were reviewed, and the subjects in this study were dental hygiene juniors at seven two-year colleges in the Seoul metropolitan area and other regions, on whom a survey was conducted for about three months from August through October, 2004, to assess their satisfaction level with their major and educational environments. And it's concluded that in order to attract more new students and foster qualified students, dental hygiene practice labs should be improved on a large scale, and that there should be a great deal of investment in teaching facilities. The major findings of the study were as follows: 1. As for satisfaction with major choice, 57.5% of the students investigated, the largest percentage, expressed satisfaction with their major. 27.8%, the second largest group, found their choice not to be bad. 2. Regarding satisfaction with the state of practice labs, 41.9% were pleased with practice labs. This rate was quite lower than that of nursing students, as 64.2% of nursing students were pleased with their practice labs.7) 3. As to satisfaction with individual practice labs, oral prophylaxis labs were considered most satisfactory, as 53.9% were satisfied with them. Digital radiation labs appeared to be satisfactory the least, which made 77.0% dissatisfied. 4. Whether there were any connections between their working experience as a clinical worker and satisfaction level was investigated. In terms of their satisfaction with major choice and the state of practice labs, the students who had ever worked as a clinical worker were relatively pleased with the state of practice labs. As for satisfaction with each practice lab, those who had ever served as a clinical worker before being admitted into college expressed more satisfaction with radiation practice labs(p<0.05) and digital radiation labs(p<.05) than the others who hadn't. The gap between the two was statistically significant. 5. In regard to the causes of dissatisfaction with practice labs, 93.7 and 80.0% were respectively dissatisfied with digital radiation labs and basic dental hygiene labs because their colleges were devoid of those labs. 51.6%, the largest group, found oral prophylaxis labs unsatisfactory because of their frequent breakdown. In the event of most of the other practice labs, the greatest percentage were discontented due to a shortage of equipment.

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RNA 간섭을 통한 Porcine Endogenous Retrovirus의 발현 억제 (Inhibition of Porcine Endogenous Retrovirus Expression by RNA Interference)

  • 이현아;구본철;권모선;김태완
    • Reproductive and Developmental Biology
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    • 제30권3호
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    • pp.181-187
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    • 2006
  • 최근 돼지의 장기를 사람에게 이식하는 이종간 장기 이식에 관한 연구가 급속히 발전되고 있다. 그러나 돼지의 장기를 이식할 경우 가장 큰 문제점 중의 하나는 돼지 genome 내에 존재하는 내인성 레트로바이러스(porcine endogenous retrovirus; PERV)가 인간에게 그대로 전이될 수 있다는 것이다. 이에 대한 대안으로 최근 활발히 연구되고 있는 RNA 간섭을 통한 PERV RNA의 발현을 최대한 억제하는 방법이 제안되고 있는데, RNA 간섭(RNA interference)은 double-standard RNA(dsRNA)가 상보적인 표적 mRNA를 분해하여 결과적으로 표적 단백질의 발현을 특이적으로 억제하는 현상을 의미한다. 본 연구에서는 PERV에 대한 RNA 간섭 현상을 일으키는 shRNA 유전자를 레트로바이러스 벡터를 이용하여 돼지세포에 RNA)가 상보적인 표적 mRNA를 분해하여 결과적으로 표적 단백질의 발현을 특이적으로 억제하는 현상을 의미하다. 도입한 후 PERV의 발현율 감소 여부를 조사하였다. 그 결과, gag-pol 유전자와 env 유전자 발현은 각각 대조군 세포의 4%와 10% 정도로 억제되었다. 한편, virus 입자의 생산에서 gag-pol 유전자는 대조군 세포에 비해 300배 이상 억제되었으며, env 유전자에서는 20만 배 이상 억제되었다. 이상의 결과를 미루어 볼 때 형질 전환 돼지를 이용한 이종 장기 이식에 있어서 RNA 간섭 현상을 이용한 PERV의 발현을 억제하는 시도는 생물학적안전성을 크게 증가시킬 수 있을 것으로 사료된다.

복강경 수술로봇을 위한 실시간 운영체제 기반 제어 시스템의 개발 (Development of a Real-time OS Based Control System for Laparoscopic Surgery Robot)

  • 송승준;박준우;신정욱;김윤호;이덕희;조영호;최재순;선경
    • 대한의용생체공학회:의공학회지
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    • 제29권1호
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    • pp.32-39
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    • 2008
  • This paper reports on a realtime OS based master-slave configuration robot control system for laparoscopic surgery robot which enables telesurgery and overcomes shortcomings with conventional laparoscopic surgery. Surgery robot system requires control system that can process large volume information such as medical image data and video signal from endoscope in real-time manner, as well as precisely control the robot with high reliability. To meet the complex requirements, the use of high-level real-time OS (Operating System) in surgery robot controller is a must, which is as common as in many of modem robot controllers that adopt real-time OS as a base system software on which specific functional modules are implemened for more reliable and stable system. The control system consists of joint controllers, host controllers, and user interface units. The robot features a compact slave robot with 5 DOF (Degree-Of-Freedom) expanding the workspace of each tool and increasing the number of tools operating simultaneously. Each master, slave and Gill (Graphical User Interface) host runs a dedicated RTOS (Real-time OS), RTLinux-Pro (FSMLabs Inc., U.S.A.) on which functional modules such as motion control, communication, video signal integration and etc, are implemented, and all the hosts are in a gigabit Ethernet network for inter-host communication. Each master and slave controller set has a dedicated CAN (Controller Area Network) channel for control and monitoring signal communication with the joint controllers. Total 4 pairs of the master/slave manipulators as current are controlled by one host controller. The system showed satisfactory performance in both position control precision and master-slave motion synchronization in both bench test and animal experiment, and is now under further development for better safety and control fidelity for clinically applicable prototype.

한국에 있어서 제수문구조물의 설계의 기준을 주기 위한 수문학적 연구(류거, 홍수 편) (The furulamelllal study in order to obtain the hydrological design basis for hydrological structures in Korea (Run ofl estimate and Flood part))

  • 박성우
    • 한국농공학회지
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    • 제8권1호
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    • pp.1011-1034
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    • 1966
  • This thesis is the final report which has long been studied by the author to obtain the design basis for various hydrological constructions with the specific system suitable to the natural environmental conditions in Korea. This report is divided into two parts: one is to estimate runoff volume from watersheds and the other to estimate the peak discharge for a single storm. According to the result of observed runoff record from watersheds, it is known that Kajiyama formula is useful instrument in estimating runoff volume from watersheds in this country. But it has been found that this formula shows us 20-30% less than the actual flow. Therefore, when wihed to bring a better result, the watershed characteristics coefficient in this formula, that is, f-value, should be corrected to 0.5-0.8. As for the method to estimate peak discharge from drainage basin, the author proposes to classify it in two ways; one is small size watershed and the other large size watershed. The maximum -flood discharge rate $Q_p$ and time to peak Pt obtained from the observed record on the small size watershed are compared by various methods and formulas which are based upon the modern hydrological knowledge. But it was fou.d that it. was not a satisfied result. Therefore, the author proposes. tocomputate $Q_p$, to present 4.0-5.0% for the total runoff volume ${\Sigma}Q$.${\Sigma}Q$ is computed under the assumption of 30mm 103s in watershed per day and to change the theoritical total flow volume to one hour dura tion total flow rate when design daily storm is given. Time to peak Pt is derived from three parameters which are u,w,k. These are computed by relationship between total runoff volume (ha-m unit)and $Q_p$. (C.M.S. unit). Finally, the author checked out these results obtained from 51 hydrographs and got a satisfied result. Therefore the author suggested the model of design dimensionless unit-hydrograph. And the author believes that this model will be much available at none runoff record river site. In the large size watersheds in Korea when the maximum discharge occurs, the effective rainfall is two consequtive stormy days. So the loss in watershed was assutned as 6Omm/2days,and the author proposed 3-hour-daration hydrograph flow distribution percentage. This distribution percentage will be sure to form the hydrograph coordinate.

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리쇼어링 제조기업의 항만배후단지 유치를 위한 정보기술아키텍쳐 활용에 관한 연구 (A Study on the Utilization of Enterprise Architecture to Attract Reshoring Manufactures into Port Logistics Park)

  • 이언경;김주미
    • 정보화연구
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    • 제11권2호
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    • pp.217-223
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    • 2014
  • 본 연구의 목적은 제조기업의 리쇼어링 원인을 파악하고, 리쇼어링 기업을 항만배후단지에 유치하기 위한 법 제도적 개선방향 및 전사적아키텍쳐(EA) 활용방안을 제시하는 것이다. 첫 번째는 문헌조사 및 기존 연구를 통해 리쇼어링 원인을 파악하고, 리쇼어링 현상이 지속될 것인가를 살펴보았다. 과거 10년 전 생산비용 절감을 위해 중국 등 해외에 진출한 미국 등 선진국의 제조기업이 상대적으로 높아진 자국의 생산비용 경쟁력, 정부의 리쇼어링(U턴)기업 지원정책, 중국 내 외국인 투자기업 경영환경 악화 등으로 인하여 본국으로 귀환하고 있다. 두 번째, 중국으로부터 리쇼어링 되는 기업을 지원하는 국내 법률을 살펴보고, 항만배후단지에 배치하기 위한 법 제도적 문제점을 파악하여 개선방향을 제시했다. 현재 법으로는 기존 글로벌 네트워크를 가지고 있는 리쇼어링 기업의 원활한 수출입 물류 지원을 할수있는 항만배후단지 활용이 어렵게 되어 있으며, 범부처적 협력도 미흡하다. 이러한 문제를 해결하기 위해 마지막으로 리쇼어링 기업이 리쇼어링 의사결정을 원활히 하고, 범부처차원에서 리쇼어링 기업을 지원하기 위한 EA 활용방안을 제시했다.

8체질침(體質鍼) 자극(刺戟)이 심박변이도(心博變移度)에 미치는 영향 (Effects of 8 Constitution Acupuncture on Heart Rate Variability)

  • 신용섭;박영재;오환섭;이상철;박영배
    • 대한한의진단학회지
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    • 제9권2호
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    • pp.94-109
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    • 2005
  • Objectives: This paper investigated the effects of 8 Constitution Acupuncture on Heart Rate Variability(HRV) and is intended to find out 8 Constitutional difference on Autonomous Function after 8 Constitution Acupuncture stimulation. Methods: The subjects were comprised of 42 volunteers(11 men and 31 women). The volunteers had acupunctured by 8 Constitution Acupuncture Therapy. HRV and Mean Heart Rate(MHR) were measured by TAS9v2.0(IEMBIO & Saerom, Korea) on two times: before and immediately after acupuncture stimulation. The SPSS 13.0 for windows was used for statistical analysis: Mann-Whitney U-test, Paired Samples T -test and Wilcoxon signed rank test were used to verify the results. Results: 1. There was no statistically significant difference on HRV and MHR between Sympathicotonia and Vagotonia before acupuncture. 2. In the whole subject, immediately after acupuncture stimulation, MHR showed a significant decrease(p<0.01) and Ln(TP), Ln(LF) and Ln(HF) showed a significant increase(p<0.05). But there was no significant difference in LHR. 3. Immediately after acupuncture stimulation, MHR showed a significant decrease and Ln(TP), Ln(HF), showed a significant increase in Pulmotonia(p<0.05), Ln(TP) showed a significant increase in Pancretonia(p<0.05),MHR showed a significant decrease and Ln(TP) showed a significant increase in Hepatonia(p<0.05), and MHR showed a significant decrease and Ln(TP), Ln(HF), showed a significant increase in cholecystonia(p<0.05). But there were no significant difference on HRV and MHR in Colonotonia and vesicotonia. Conclusion: The results suggest that 8 Constitution Acupuncture is associated with changed activity in sympathetic and parasympathetic nervous system. Further study is needed for investigating the effects of 8 Constitution Acupuncture on HRV and autonomic nervous system.

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