• 제목/요약/키워드: tightly-coupled

검색결과 150건 처리시간 0.021초

An early transcription checkpoint ; A dual role of capping enzyme in RNA polymerase II transcription

  • Cho Eun-Jung
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2005년도 춘계학술대회
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    • pp.5-14
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    • 2005
  • Recently, data from several groups have raised the concept of 'checkpoint' in transcription. As capping of nascent RNA transcript is tightly coupled to RNA polymerase II transcription, we seek to obtain direct evidence that transcripiton checkpoint via capping enzyme functions in this early regulatory step. One of temperature sensitive (ts) alleles of ceg1, a guanylyltransferase subunit of the Saccharomyces cerevisiaecapping enzyme, showed 6-azauracil (6AU) sensitivity at the permissive growth temperature, which is a phenotype that is correlated with a transcription elongational defect. This ts allele, ceg1-63 also has an impaired ability to induce PUR5 in response to a 6AU treatment. However, this cellular and molecular defect is not due to the preferential degradation of the transcript attributed from a lack of guanylyltransferase activity. On the contrary, the data suggests that the guanylyltransferase subunit of the capping enzyme plays a role in transcription elongation. First, in addition to the 6AU sensitivity, ceg1-63is synthetically lethal with elongation defective mutations of the largest subunit of RNA polymerase II. Secondly, it exhibited a lower GAL1 mRNA turn-over after glucoseshut off. Third, it decreased the transcription read through a tandem array of promoter proximal pause sites in an orientation dependent manner. Interestingly, this mutant also showed lower pass through a pause site located further downstream of the promoter. Taken together, these results suggest that the capping enzyme plays the role of an early transcription checkpoint possibly in the step of the reversion of repression by stimulating polymerase to escape from the promoter proximal arrest once RNA becomes appropriately capped.

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객체지향 데이터베이스를 이용한 지식베이스 모형(OOKS) 개발 (Development of OOKS : a Knowledge Base Model Using an Object-Oriented Database)

  • 허순영;김형민;양근우;최지윤
    • 지능정보연구
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    • 제5권1호
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    • pp.13-34
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    • 1999
  • Building a knowledge base effectively has been an important research area in the expert systems field. A variety of approaches have been studied including rules, semantic networks, and frames to represent the knowledge base for expert systems. As the size and complexity of the knowledge base get larger and more complicated, the integration of knowledge based with database technology cecomes more important to process the large amount of data. However, relational database management systems show many limitations in handing the complicated human knowledge due to its simple two dimensional table structure. In this paper, we propose Object-Oriented Knowledge Store (OOKS), a knowledge base model on the basis of a frame sturcture using an object-oriented database. In the proposed model, managing rules for inferencing and facts about objects in one uniform structure, knowledge and data can be tightly coupled and the performance of reasoning can be improved. For building a knowledge base, a knowledge script file representing rules and facts is used and the script file is transferred into a frame structure in database systems. Specifically, designing a frame structure in the database model as it is, it can facilitate management and utilization of knowledge in expert systems. To test the appropriateness of the proposed knowledge base model, a prototype system has been developed using a commercial ODBMS called ObjectStore and C++ programming language.

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HIGH-TPI HDD 구현을 위한 PES ESTIMATION에 관한 연구 (A Study on the PES Estimation for Developing High-TPI HDD)

  • 고정석;강성우;한윤식;김영훈;황태연
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 추계학술대회논문집
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    • pp.122-127
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    • 2002
  • A frequency-domain PES estimation and its prediction method are proposed for the tightly-coupled servo/mechanical design of high-TPI HDD system above 100 kTPI. The major two disturbance energies which are related with mechanical vibrations inside of HDD are used to predict the drive-level PES, while considering closed-loop servo dynamics. One is the torque disturbance which mainly comes from aerodynamic excitation of HSA system and the other is the displacement disturbance from disk-spindle dynamics. In order to obtain the accurate error transfer function of closed-loop servo control, the plant model is measured by accurate experiment. The measured PES is compared with predicted one in terms of frequency-domain PES spectrum and its standard variation value. It is proved that the proposed frequency-domain PES estimation/prediction method is capable of predicting drive-level PES of high-TPI hard disk drive.

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시그마 포인트 기반 RHKF 필터를 사용한 지상합법용 DR/GPS 결합시스템의 성능 향상 (Improving the Performance of DR/GPS Integrated System For Land Navigation Using Sigma Point Based RHKF Filter)

  • 최완식;조성윤
    • 제어로봇시스템학회논문지
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    • 제12권2호
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    • pp.174-185
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    • 2006
  • This paper describes a DR construction for land navigation and the sigma point based receding horizon Kalman FIR (SPRHKF) filter for DR/GPS hybrid navigation system. A simple DR construction is adopted to improve the performance both of the pure DR navigation and the DR/GSP hybrid navigation system. In order to overcome the flaws of the EKF, the SPKF is merged with the receding horizon strategy. This filter has several advantages over the EKF, the SPKF, and the RHKF filter. The advantages include the robustness to the system model uncertainty, the initial estimation error, temporary unknown bias, and etc. The computational burden is reduced. Especially, the proposed filter works well even in the case of exiting the unmodeled random walk of the inertial sensors, which can be occurred in the MEMS inertial sensors by temperature variation. Therefore, the SPRHKF filter can provide the navigation information with good quality in the DR/GPS hybrid navigation system for land navigation seamlessly.

소프트웨어 유지보수 도구를 위한 자료 저장소의 설계 (A Design of Data Repository for Software Maintenance Tools)

  • 최은만
    • 한국정보처리학회논문지
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    • 제2권2호
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    • pp.168-175
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    • 1995
  • 성공적인 소프트웨어 개발 환경을 구축하기 위하여 도구 사이의 인터페이스가 잘 정의되어야 한다. 최근에 활발히 연구되는 CASE 도구들이 잘 결합하여 일관성있는 환경이 되기 위해서는 자료 저장소의 설계가 중요하다. 특히 요지보수를 위한 도구 개 발은 원시 코드의 변경과 프로그램으로 표현된 객체들 사이의 상호관계를 잘 나타내도 록 자료 저장소를 설계하여야 한다. 본 논문에서는 소프트웨어 유지보수 환경 구축에 필요한 자료 저장소 설계에 통합 방법을 도입하였다. 유지보수 대상 객체들을 정의하 고 객체들 사이의 관계를 나타내었으며 자료 저장소를 접근하기 위한 방법도 제안하 였다. 이 방법에 의하면 유지보수하는 동안 변경을 관리하기 위한 버젼 및 현상관리 뿐만 아니라 질의 서비스, 자료교환 서비스가 효율적으로 이루어진다.

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카메라 영상을 이용한 연기 및 화염의 조기 감지 최신 연구 동향 (Survey for Early Detection Techniques of Smoke and Flame using Camera Images)

  • 강성모;김종면
    • 한국컴퓨터정보학회논문지
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    • 제16권4호
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    • pp.43-52
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    • 2011
  • 시대가 발전함에 따라 초고층 건물들이 도처에 세워지고 밀집되어 있다. 이러한 건물에 화재가 발생되면 발화지점 근처로 불이번지면서 대형화재의 위험성이 높아지고 이에 따른 인명 및 재산 피해가 증가한다. 따라서 이런 대형화재를 예방하고 피해를 최소화하기 위해서 화재를 미연에 감지하는 화재감지 기술에 대한 필요성이 높아지고 있다. 화재를 감지하기 위해 열감지기, 연기감지기, 불꽃감지기 등을 사용하는 방법이 있으나 본 논문에서는 감시 카메라에서 들어오는 입력 영상을 분석하여 화염과 연기를 초기에 감지하는 화재감지 시스템의 최근 연구 동향을 알아보고자 한다. 또한 이러한 화염과 연기 감지 알고리즘들을 다양한 형태의 동영상을 이용하여 구현 및 성능을 평가하였다.

가정용 지능형 경비 로봇 시스템 개발 (Development of an Intelligent Security Robot System for Home Surveillance)

  • 박정호;신동관;우춘규;김형철;권용관;최병욱
    • 제어로봇시스템학회논문지
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    • 제13권8호
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    • pp.810-816
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    • 2007
  • A security robot system named EGIS-SR is a mobile security robot through one of the new growth engine project in robotic industries. It allows home surveillance through an autonomous mobile platform using onboard cameras and wireless security sensors. EGIS-SR has many sensors to allow autonomous navigation, hierarchical control architecture to handle lots of situations in monitoring home surveillance and mighty networks to achieve unmanned security services. EGIS-SR is tightly coupled with a networked security environment, where the information of the robot is remotely connected with the remote cockpit and patrol man. It achieved an intelligent unmanned security service. The robot is a two-wheeled mobile robot and has casters and suspension to overcome a doorsill. The dynamic motion is verified through $ADAMS^{TM}$ simulation. For the main controller, PXA270 based hardware platform based on linux kernel 2.6 is developed. In the linux platform, data handling for various sensors and the localization algorithm are performed. Also, a local path planning algorithm for object avoidance with ultrasonic sensors and localization using $StarGazer^{TM}$ is developed. Finally, for the automatic charging, a docking algorithm with infrared ray system is implemented.

A data management system for microbial genome projects

  • Ki-Bong Kim;Hyeweon Nam;Hwajung Seo and Kiejung Park
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2000년도 International Symposium on Bioinformatics
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    • pp.83-85
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    • 2000
  • A lot of microbial genome sequencing projects is being done in many genome centers around the world, since the first genome, Haemophilus influenzae, was sequenced in 1995. The deluge of microbial genome sequence data demands new and highly automatic data flow system in order for genome researchers to manage and analyze their own bulky sequence data from low-level to high-level. In such an aspect, we developed the automatic data management system for microbial genome projects, which consists mainly of local database, analysis programs, and user-friendly interface. We designed and implemented the local database for large-scale sequencing projects, which makes systematic and consistent data management and retrieval possible and is tightly coupled with analysis programs and web-based user interface, That is, parsing and storage of the results of analysis programs in local database is possible and user can retrieve the data in any level of data process by means of web-based graphical user interface. Contig assembly, homology search, and ORF prediction, which are essential in genome projects, make analysis programs in our system. All but Contig assembly program are open as public domain. These programs are connected with each other by means of a lot of utility programs. As a result, this system will maximize the efficiency in cost and time in genome research.

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이동 애드 혹 네트워크상에서 멀티미디어 서비스를 위한 크로스레이어 기반의 전송 기법 (Cross-layer based Transmission Scheme for Multimedia Service over Mobile Ad Hoc Network)

  • 안기진;주현철;송황준
    • 한국통신학회논문지
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    • 제34권11B호
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    • pp.1216-1224
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    • 2009
  • 본 논문에서는 이동 애드 혹 네트워크상에서 지연에 민감한 멀티미디어 데이터를 효과적으로 전송하기 위한 크로스레이어 기반 패킷 스케줄링 및 라우팅 기법을 제안한다. 우선 패킷 긴급도, 노드 긴급도, 경로 긴급도를 각 패킷의 종단 간 지연 요구사항과 경로 상의 전체 홉 수를 고려하여 정의한다. 제안하는 기법은 긴급도 척도를 기반으로 MAC 계층에서의 패킷 스케줄링 기법과 네트워크 계층에서의 라우팅 기법이 긴밀하게 결합되어 이동 애드 혹 네트워크상에서 지연에 민감한 멀티미디어의 전송 성능을 향상시킨다. 마지막으로, 실험 결과를 통해 제안 하는 전송 기법의 성능을 검증한다.

다중프로세서 시스템에서 파이프라인 전송 버스의 설계 및 성능 평가 (Design of Pipeline Bus and the Performance Evaluation in Multiprocessor System)

  • 윤용호;임인칠
    • 한국통신학회논문지
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    • 제18권2호
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    • pp.288-299
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    • 1993
  • 본 논문은 단일 버스를 사용한 밀결합 다중프로세서 시스템에서 데이타 전송량을 극대화하기 위해 파이프라인 전송 기능을 가지는 버스 프로토콜를 제안한다. 이 버스는 어드레스와 데이타의 전송을 위해 독립적인 전송 통로와 블록 전송기능을 두고, 최애 264 Mbytes/sec 데이타의 전송 능력을 가진다. 이버스를 기반으로 각각의 프로세서 보드의 내부에 캐쉬를 포함한 다중프로세서 시스템을 모델링하고, 시뮬레이션를 통해 캐쉬의 메모리의 참조율 변화에 따른 버스의 성능 및 시스템의 성능을 평가한다. 본 버스를 이용할 경우 10개 까지의 프로세서 보드가 버스에 장착되어도 버스가 포화되지 않고, 4개 까지의 메모리의 인디리빙에 대하여 성능이 선형적으로 증가함을 알 수 있다.

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