• Title/Summary/Keyword: Data base

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A Study of Construction of Character Image Data for Recognition Handwritten Text (필기체 문자 인식을 위한 문자 영상 데이터 구축에 관한 연구)

  • Lee, H.R.;Ko, K.C.;Lee, M.R.
    • Annual Conference on Human and Language Technology
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    • 2000.10d
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    • pp.63-67
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    • 2000
  • In order to develop a character recognition system, it is an essential preceding work that gathers an image data of the standard. On this purpose a data of the digitized images of a handwritten characters was collected. The types of a gathered image data are Korean character, Chiness character, Numeral, English character, Special character, and so on. This paper deals with a handwritten character image data base, and the image data base different from the general storage structure of a lame capacity multimedia was designed and builded.

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Development of Expert System for Tower Cranes

  • Kim, Ki-sung;Kang, Dong-gil;Hong, Ki-sup
    • Journal of Ship and Ocean Technology
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    • v.3 no.2
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    • pp.27-48
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    • 1999
  • The paper is concerned with application to develop the expert system, which structural analysis and design process for tower cranes. The system is organized into three groups. One is pre-processor for creating input data files, another is `model former' which combines knowledge-base with inference engine for automatic generating structural analysis models, a third is application group for final analysis checks. In this study, geometric subroutine of `model former' designates node positions, nodes, elements numbers and element types. Load data subroutine computes weight of tower crane and device, slewing force, cargo load, wind force form rules or equations in knowledge-base. Also, Property and boundary subroutine applies element properties and boundary conditions to suitable elements and nodes. Design and analysis expert system for tower crane integrates these subroutine, `model former' and pre-processor. RBR(Rule-Base Reasoning) was adopted for a reasoning strategy of this expert system. And this expert system can produce structural analysis model and data, which can be used in ordinary structural analysis program (SAP, ADINA or NASTRAN, etc.). In this paper, this expert system produces format of the analysis model data, which are used in MSC/NASTRAN. The main discussions included in the paper are introduction of the tower crane and structural analysis, composition of the design expert system for tower crane and structural analysis using the expert system.

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A Fundamental Study for Establishment of Channel Data Base in Power-Line Communications (전력선 통신 채널 Data Base 구축을 위한 기본 연구)

  • Oh, Hui-Myoung;Kim, Kwan-Ho;Lee, Won-Tae;Lee, Jae-Jo
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2619-2621
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    • 2002
  • 전력선 통신(Power-Line Communication)은 기본적으로 데이터 전송용이 아닌 전력 전달을 목적으로 설계된 전력선을 매체로 이루어지기 때문에 상당한 잡음과 감쇠 특성을 보이며 또 전력선 topology와 부하의 변화에 따라 전달 함수(transfer function)의 변화도 심하다. 이러한 열악한 채널 특성을 극복하기 위해 전력선 채널에 관한 많은 연구가 진행되고 있으며 그 중에서도 채널 모델링 연구가 활발하게 진행되고 있다. 채널 모델링은, 변복조 방식, 채널 코딩(coding), 커플링(coupling), 필터링(filtering) 등의 적극적인 채널 극복 방안으로서 제시되는 기술을 적용함에 있어서 상당히 중요하다. 본 논문에서는, 채널 모델링 기법으로 제시되고 있는 방식인, 전달 함수 특성과 여러 가지 잡음 특성을 결합한 통계적 모델링 방식[l]을 통해 전력선 채널 모델을 구현하여 실측치와 비교 검토하고, 또 모델링을 통해 얻어지는 파라미터(parameter)를 통해 채널 정보를 효과적으로 Data Base화 할 수 있는 방안에 대해 연구하였으며, 이 Data Base의 활용 방안을 모색하였다.

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The MLMEX Design and Implemention for Vehicle Communication Technology (차량 통신 기술을 위한 MLMEX 설계 및 구현)

  • Lee, Dae Sik;Lee, Yong Kwon
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.1
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    • pp.103-110
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    • 2013
  • WAVE system is a vehicle communication technology. The system provides the services to prevent vehicle accidents that might occur during driving. Also, it is used to provide various services such as monitoring vehicle management and system failure. In this paper, we divide module that manages WAVE MAC state into a WSMP base MLME module and IP base module and we design and implement a parameter environment between WME module to manage the state of the WAVE system and MLMEX module to mange IP base of WAVE MAC therefore the date to be processed.Also, in order to verify the validity, we have carried out experiments to compare the speed of data processing by dividing data of 5Mbyte, 10Mbyte, 20Mbyte into the packets of 2KByte and 4KByte. Therefore, in WAVE system, the Parameter environments and data processing speed between WME and MLMEX module can be utilized in the various service of vehicle communication technology depending on the speed of data processing.

A novel risk assessment approach for data center structures

  • Cicek, Kubilay;Sari, Ali
    • Earthquakes and Structures
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    • v.19 no.6
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    • pp.471-484
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    • 2020
  • Previous earthquakes show that, structural safety evaluations should include the evaluation of nonstructural components. Failure of nonstructural components can affect the operational capacity of critical facilities, such as hospitals and fire stations, which can cause an increase in number of deaths. Additionally, failure of nonstructural components may result in economic, architectural, and historical losses of community. Accelerations and random vibrations must be under the predefined limitations in structures with high technological equipment, data centers in this case. Failure of server equipment and anchored server racks are investigated in this study. A probabilistic study is completed for a low-rise rigid sample structure. The structure is investigated in two versions, (i) conventional fixed-based structure and (ii) with a base isolation system. Seismic hazard assessment is completed for the selected site. Monte Carlo simulations are generated with selected parameters. Uncertainties in both structural parameters and mechanical properties of isolation system are included in simulations. Anchorage failure and vibration failures are investigated. Different methods to generate fragility curves are used. The site-specific annual hazard curve is used to generate risk curves for two different structures. A risk matrix is proposed for the design of data centers. Results show that base isolation systems reduce the failure probability significantly in higher floors. It was also understood that, base isolation systems are highly sensitive to earthquake characteristics rather than variability in structural and mechanical properties, in terms of accelerations. Another outcome is that code-provided anchorage failure limitations are more vulnerable than the random vibration failure limitations of server equipment.

A Study on the Shelf-Life Prediction of the Domestic Single Base Propellants Ammunition : Based on 105mm High Explosive Propellants (국내 단기추진제 탄약의 저장수명 예측에 관한 연구 : 105미리 고폭탄 추진체를 중심으로)

  • Choi, Myoungjin;Park, Hyungju;Yang, Jaekyung;Baek, Janghyun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.37 no.3
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    • pp.36-42
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    • 2014
  • Domestic 105mm HE (High Explosive) shell is composed of three parts that are Fuze, Projectile and Propellants. Among three parts, propelling charge of propellants part consists of single base propellants. It has been known that the lifespan of single base propellants is affected by a storage period. These are because Nitrocellulose (NC) which is the main component of propelling gunpowder can be naturally decomposed to unstable substances similar with other nitric acid ester. Even though it cannot be prevented fundamentally from being disassembled, a decomposition product ($NO_2$, $NO_3$, and $HNO_3$) and tranquillizer DPA (Diphenylamine) having high reactivity are added into a propellant to restrain induction of automatic catalysis by a decomposition product. The decay rate of the tranquillizer is also affected by a production rate of the decomposition product of NC. Therefore, an accurate prediction of the Self-Life is required to ensure against risks such as explosion. Hereupon, this paper presents a new methodology to estimate the shelf-life of single base propellants using data of ASRP (Ammunition Stockpile Reliability Program) to domestic 105mm HE (propelling charge of propellants part). We selected four attributes that are inferred to have influence on distribution of the DPA amount in a propellant from the ASRP dataset through data mining processes. Then the selected attributes were used as independent variables in a regression analysis in order to estimate the shelf-life of single base propellants.

Synthesis and Characterization of Schiff Base Metal Complexes and Reactivity Studies with Malemide Epoxy Resin

  • Lakshmi, B.;Shivananda, K.N.;Prakash, Gouda Avaji;Isloor, Arun M.;Mahendra, K.N.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.2
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    • pp.473-482
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    • 2012
  • A novel malemide epoxy containing Co(II), Ni(II) and Cu(II) ions have been synthesized by curing malemide epoxy resin (MIEB-13) and Co(II), Ni(II) and Cu(II) complexes of macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting 1,4-dicarbnyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol. The Schiff base and its Co(II), Ni(II) and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, $^1H$ NMR, UV-vis., FAB mass, ESR), thermal and magnetic data. The curing reaction of maleimide epoxy compound with metal complexes was studied as curing agents. The stability of cured samples was studied by thermo-gravimetric analyses and which have excellent chemical (acid/alkali/solvent) and water absorption resistance. Further, the scanning electron microscopy (SEM) and definitional scanning colorimetric (DSC) techniques were confirmed the phase homogeneity of the cured systems.

Extracting and Characterization of the Base Resistance based on Analysis of the Equivalent Noise Circuit for Common Collector (공통컬렉터 잡음등가회로 해석에 의한 베이스저항의 추출 및 특성)

  • Gu, Hoe-U;Lee, Gi-Yeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.2
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    • pp.1-4
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    • 2000
  • We presented a method for extracting the base resistance r/sun bb/ based on analysis of the equivalent noise circuit for common collector. Measurements were conducted on devices with poly-emitter structure fabricated by BiCMOS process. Base resistance measurements have been performed for different base currents and structure. For low base current it is shown that the experimental data agree with theoretical expectations.

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A State-Space Transient Response Analysis of Rotor-Bearing System with Base Excitation (기초가진 로터-베어링 시스템의 상태공간 과도응답해석)

  • 이안성;김병옥;김영철;김영춘
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.669-674
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    • 2004
  • In this study, the analytical method to evaluate the response of rotor-bearing system subjected to base excitation was presented. The equations of motion contain speed dependent gyroscopic terms, base rotation dependent parametric terms and several forcing function terms which depend on linear accelerations, rotational accelerations and a combination of linear and rotational combination. The study of rotor-bearing system excited by its base motion is not only able to predict the rotational performance, but provides the fundamental data for vibration isolation. In order to illustrate transient response, transient response analysis of a practical application sample were performed. The transient response was carried out for the given base excitation by using the state-space Newmark method that incorporates the average velocity concept.

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