• 제목/요약/키워드: BASE

검색결과 23,370건 처리시간 0.05초

고속제트 플럼에서의 기저압력 특성 (Characteristics of the Base Pressure in High-Speed Jet Plume)

  • ;김희동
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2011년도 제36회 춘계학술대회논문집
    • /
    • pp.193-195
    • /
    • 2011
  • An abrupt increase of duct cross-section is frequently encountered in pressure reducing devices, valves of internal combustion engines and in gas pipelines. Supersonic flow in a rectangular duct passing an abrupt increase of cross-section is studied numerically. The behavior of base pressure of the dead-air region at sudden enlargement of the duct is clarified. This investigation concerns the determination of the base pressure, which is independent of the size of the enlarged part. Several flow patterns are identified with different enlargements according to the ratio between the downstream ambient pressure and the upstream reservoir pressure. Base pressure and the resulting shock-structure are highly depending on the size of duct enlargement. For a given duct, base pressure tends to minimum for a particular pressure ratio. In addition, the locations of secondary separation and reattachment points of the jet plume are found with respect to different duct enlargements.

  • PDF

상징어 어근으로 형성된 한국어 성격 형용사 연구 (A Study on Character Adjectives in Korean that Have Symbolic Words as Roots)

  • 김홍범;권경일
    • 비교문화연구
    • /
    • 제19권
    • /
    • pp.233-250
    • /
    • 2010
  • This study aims to observe the features of Korean adjectives composed with symbolic base impling human character. Korean adjectives composed with symbolic base shows more delicate nuances than ordinary adjectives. For observing the feature of them we analyzed the 6000 symbolic words in 'Stanadard Korean Dictionary'. As a result,the symbolic base of adjectives is divided into the one that maintain the basic meaning of symbolic words and the other that do not maintain basic meaning of symbolic words. The base that maintain the basic meaning of symbolic words is divided into the one that has meaning of character and the other that do not has meaning of character. The base that do not maintain the basic meaning of symbolic words is divided into the one that can relate with '-hada' and the other that cannot relates with '-hada'. This study remains the problem in future to examine common points of symbolic base.

철도차량기지용 단권변압기의 전압강하에 대한 이론적 고찰 (A Theoretical Study on Voltage Drop of Auto-Transformer for Railway Vehicle Base)

  • 유기성;김재문
    • 전기학회논문지
    • /
    • 제67권12호
    • /
    • pp.1723-1728
    • /
    • 2018
  • In order to investigate the voltage drop compensation effect of AT for domestic railway vehicle base, the parameters of AT voltage drop of railroad car base are Z3 (Impedance of feeder line), Xn ( Distance from railroad vehicle to AT to SS), and Dn (distance between both ATs of railway vehicle).In addition, when installed in a SSP for a railway vehicle base, there is no AT and feeder line in the railway vehicle base except for the SSP for the main line and the SSP for the railway vehicle base, so that if zero or ignored, the AC single-phase two- It can be confirmed that it becomes a form.

범용 DSP를 이용한 RRS 기반 기지국 통신 플랫폼 구현 (Implementation of RRS-based Base station Communication platform using General-Purpose DSP)

  • 김호일;안흥섭;최승원
    • 디지털산업정보학회논문지
    • /
    • 제14권4호
    • /
    • pp.87-92
    • /
    • 2018
  • One of the problems with the base station equipment is that there is a large difference between the replacement time of the hardware equipment such as the base station equipment and the radio access equipment, and the evolution period of the communication standard. Therefore, the base station communication platform must be flexible enough to handle the evolving communication standards after purchase. Recent research on reconfigurable communications platforms has focused on the efficient architecture of the communications platform to meet these requirements through software downloads while still using existing hardware. This paper presents a prototype of a base station communications platform based on the ETSI standard reconfigurable architecture. The communication platform presented in this paper is implemented as an ETSI standard reconfigurable architecture using a general-purpose DSP (Digital Signal Processor). In the implemented prototype, we verify the real-time feasibility of communication protocol updates through software reconfiguration.

Knoledge Base Incorporated with Neural Networks

  • G.Y. Lim;Lee, K.Y..;E. H. Cho;Baek, D. S;Moon, S.R..;Kim, H. Y .
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
    • /
    • pp.410-412
    • /
    • 1998
  • Subsymbolic Knowledge processing is said to be changed states of networks constructed from small elements. subsymbolic systems also make it possible to use connectionist models for knowledge processing. Connectionist realization such modulus are modulus linked together for solving a given problem. We study using neural networks as distinct actions. The output vectors produced by the neural networks are consider as a new facts. These new facts are then processed to activate another networks or used in the current production rule, The production rule is applying knowledge stored in the knowledge base to make inference. After neural networks knowledge base is constructed and trained. We present a running sample of incorporating neural network knowledge base. We implement using rochester connectionist simulator. We suggest that incorporating neural network knowledge base. Therefore incorporated neural network knowledge base ensures a cleaner solution which results in better perfor s.

  • PDF

Web Server DataBase를 이용한 안드로이드 어플리케이션 개발 (Development of An Adroid Application with An Web Server DataBase)

  • 박한국;홍민
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2011년도 추계학술발표대회
    • /
    • pp.1082-1084
    • /
    • 2011
  • 최근 스마트폰의 보급률이 급격하게 증가함에 따라 스마트폰 사용자들이 요구하는 어플리케이션들도 더욱 다양해지고 어플리케이션들의 효율성 또한 높아져야하는 상황이다. 또한 대부분의 스마트폰 어플리케이션들이 데이터를 효율적으로 저장, 관리하기 위해서 DataBase를 이용하고 있다. 비록 하드웨어기술이 눈부시게 발전하기는 했지만, 아직까지는 제한적인 스마트폰 기기의 하드웨어 환경상 효율적인 어플리케이션을 개발하기 위해서는 DataBase를 효율적으로 설계하고 각종 쿼리문을 적절하게 활용하여 최적의 성능을 제공할 수 있도록 구현되어야 한다. 따라서 본 연구는 변경사항이 적은 Data는 SQLite를 이용하여 스마트폰 어플리케이션 내부의 DataBase에 저장하고, 변동이 잦은 Data는 별도의 Server DataBase를 이용하여 스마트폰과의 네트워크 통신을 이용한 연동을 통해 어플리케이션의 내용이 업데이트 되도록 설계하였다.

크로스핏 파워 트레이닝이 TPI OnBaseU Power Test와 골프 수행력에 미치는 영향 (Effect of CrossFit Power Training on TPI OnBaseU Power Test and Golf Performance)

  • Chang Wook Kim
    • 한국운동역학회지
    • /
    • 제33권4호
    • /
    • pp.185-195
    • /
    • 2023
  • Objective: The purpose of this study is to improve TPI OnBaseU Power Test and golf performance by conducting CrossFit power training. Method: Three male golf players from University B participated in this study. They had 3 to 4 years of golf experience and participated in 8 weeks of CrossFit power training. Results: OnBaseU Power Test: There was a lot of improvement in Sit up throw (27.9%) and Chest pass (10.58%), but there was not much improvement in Baseline Toss (R5.9, L9.8%) and Vertical Jump (4.1%). Golf shot data: There was a very statistically significant difference in Club speed, Ball speed, and Total Length, which are related to speed, and there was no difference in Club path and Smash factor, which are related to accuracy and posture. Conclusion: CrossFit power training was effective in improving TPI OnBaseU Power Test and golf performance (Club speed, Ball speed, Total Length).

표준 탄도모델 기반 항력감소탄의 모터 자료 결정에 관한 연구 (A Study on Determination of Motor Data of a Base-Bleed Projectile based on Standard Ballistic Model)

  • 박용인;이치훈;고영성
    • 한국군사과학기술학회지
    • /
    • 제27권1호
    • /
    • pp.31-42
    • /
    • 2024
  • In this study, the methodology of determination of base bleed motor data for base bleed projectile based on the NATO standard trajectory model, especially STANAG 4355 Method 2 were presented. Ground combustion experiments and aerodynamic performance firing tests were conducted to determine the drag reduction motor data of the base bleed projectile and this data was described based on the NATO standard ballistic model. The derived drag reduction motor data were input into the ballistic equations to complete the ballistic model and it was confirmed that the calculated predicted trajectory from the ballistic model matched well with the measured trajectory from the aerodynamic performance firing tests.

CAD/CAM 의치상 레진과 열중합 의치상 레진의 두께에 따른 굴곡 강도 비교 (Comparison of flexural strength according to thickness between CAD/CAM denture base resins and conventional denture base resins)

  • 이동형;이준석
    • 구강회복응용과학지
    • /
    • 제36권3호
    • /
    • pp.183-195
    • /
    • 2020
  • 목적: 이 논문의 목적은 CAD/CAM 의치상 레진과 열중합 의치상 레진의 굴곡 강도를 비교해보고, 두께에 따른 굴곡 강도 변화도 비교해보는 것이다. 연구 재료 및 방법: 열중합 의치상 레진은 Lucitone 199® (C-LC)을 사용하였다. 3D printing 의치상 레진으로는 DIOnavi - Denture (P-DO)와 DENTCA - Denture Base II (P-DC)를 사용하였다. 밀링 PMMA 블록으로는 Vipi Block Gum (M-VP)과 M-IVoBase® CAD (M-IV)를 사용하였다. 시편의 최종 규격은 65.0 mm × 12.7 mm × 1.6 mm / 2.0 mm / 2.5 mm였다. 굴곡 강도와 굴곡 탄성율을 측정하기 위해 3점 굽힘 시험을 실시하였다. 그리고 파절된 시편의 단면을 주사전자현미경 (SEM) 을 사용하여 분석하였다. 데이터의 정규성을 확인한 뒤 일원분산분석(one-way ANOVA)을 사용하여 유의 수준 P = 0.05로 설정하여 그룹 간의 차이를 평가한 뒤, 사후 분석을 위해 Tukey HSD test를 시행하였다. 결과: 동일 두께 내에서, P-DO를 제외한 나머지 CAD/CAM 의치상 레진들과 열중합 의치상 레진의 굴곡 강도는 유의한 차이를 나타내었다. M-VP는 열중합 의치상 레진 보다 굴곡 강도가 높게 나타났고, P-DC와 M-IV는 낮은 굴곡 강도를 보였다. 굴곡 탄성률은 M-VP에서 제일 높게 나타났고 C-LC, P-DO, P-DC, M-IV 순으로 낮아졌으며 재료간에 모두 유의한 차이가 나타났다. 두께에 따른 굴곡 강도는, C-LC에서는 2.5 mm가 1.6 mm보다 유의하게 높은 굴곡 강도를 보였고, P-DC, M-VP는 2.5 mm와 2.0 mm에서 1.6 mm보다 유의하게 높은 굴곡 강도가 나타났다. M-IV에서는 두께가 증가할수록 유의한 굴곡 강도 증가가 나타났다. SEM 분석 결과 서로 다른 재료들의 파절된 단면은 각기 다른 양상을 띄었다. 결론: 본 연구에서 사용된 CAD/CAM 의치상 레진의 굴곡 강도는 각 재료의 성분 및 특성에 따라 다양하게 나타났다. CAD/CAM 의치상 레진의 굴곡 강도는 두께가 감소하여도 1.6 mm 이상의 두께에서는 ISO 20795-1:2013에서 제시하는 굴곡 강도보다 높게 나타났다. 하지만 보다 얇은 두께의 의치를 임상적으로 사용하기 위해서는, 더 낮은 두께의 의치상 레진의 다른 특성들에 관한 추가적인 연구가 필요하다.