• Title/Summary/Keyword: Spatial Limitation

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Man-hour Reduction by Development of Library in a 3-D Design System for Plant Projects (플랜트 프로젝트용 3차원 디자인 시스템에서 라이브러리 개발을 통한 설계시간 감축)

  • Lee, Jung-Hyun;Moon, Seung-Jae;Yoo, Hoseon
    • Plant Journal
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    • v.5 no.4
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    • pp.68-72
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    • 2009
  • This study discussed for library development of the 3 dimensional design system for the progressive developmental world wide plant industry. Its previous background had spatial limitation by utilizing 2 dimensional CAD. This work presented an effective mode for improving man-hour by applying with 3 dimensioal design system through theoretical definition, category, and means of basic man-hour. We researched an effective method for reducing man-hour through applied example on the actual project by comprehending affection of extra development for library on man-hour.

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Design of Internal based Monitoring and Control System for Tiny PLC (소형 PLC를 위한 인터넷 기반 모니터링 및 제어 시스템 설계)

  • Kang, Jung-Kyu;Na, Kwang-Ju;Kim, Sung-Ho
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2811-2813
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    • 2000
  • Nowadays PLC is used for controlling various industrial processes. For its better performance operating status of PLC should be continuously checked. However. it is difficult to monitor the status of PLC owing to the spatial limitation. This paper presents an internet based remote monitoring and control system for PLC and a practical implementation for Tiny PLC is executed for verifying its feasibility.

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Velocity Vector Imaging (속도 벡터 영상 방법)

  • Kwon, Sung-Jae
    • The Journal of the Acoustical Society of Korea
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    • v.29 no.1E
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    • pp.11-27
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    • 2010
  • Nowadays, ultrasound Doppler imaging is widely used in assessing cardiovascular functions in the human body. However, a major drawback of ultrasonic Doppler methods is that they can provide information on blood flow velocity along the ultrasound beam propagation direction only. Thus, the blood flow velocity is estimated differently depending on the angle between the ultrasound beam and the flow direction. In order to overcome this limitation, there have been many researches devoted to estimating both axial and lateral velocities. The purpose of this article is to survey various two-dimensional velocity estimation methods in the context of Doppler imaging. Some velocity vector estimation methods can also be applied to determine tissue motion as required in elastography. The discussion is mainly concerned with the case of estimating a two-dimensional in-plane velocity vector involving the axial and lateral directions.

Methodological Review on Functional Neuroimaging Using Positron Emission Tomography (뇌기능 양전자방출단층촬영영상 분석 기법의 방법론적 고찰)

  • Park, Hae-Jeong
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.2
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    • pp.71-77
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    • 2007
  • Advance of neuroimaging technique has greatly influenced recent brain research field. Among various neuroimaging modalities, positron emission tomography has played a key role in molecular neuroimaging though functional MRI has taken over its role in the cognitive neuroscience. As the analysis technique for PET data is more sophisticated, the complexity of the method is more increasing. Despite the wide usage of the neuroimaging techniques, the assumption and limitation of procedures have not often been dealt with for the clinician and researchers, which might be critical for reliability and interpretation of the results. In the current paper, steps of voxel-based statistical analysis of PET including preprocessing, intensity normalization, spatial normalization, and partial volume correction will be revisited in terms of the principles and limitations. Additionally, new image analysis techniques such as surface-based PET analysis, correlational analysis and multimodal imaging by combining PET and DTI, PET and TMS or EEG will also be discussed.

Uniform field emission on ink-jet printed CNT emitters through oxygen trimming

  • Song, Dae-Hun;Yun, Ho-Gyu;Han, Jong-Hun;Kim, Seong-Hyeon;Lee, Gyeong-Il;Lee, Cheol-Seung;Lee, Nae-Seong;Lee, Han-Seong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.450-450
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    • 2010
  • Recently, field emission emitters made by carbon nanotubes(CNTs) and ink-jet method have been extensively studied due to their low cost, little limitation of size and a high resolution. When CNT emitters are operated, a few highly protruded ones generate most of the emission currents that cause spatial nonuniformity. In this study, we applied selective oxidation to solve this problem on ink-jet printed CNT emitters. Consequently, O2 exposures to field emitting CNT arrays give rise to a permanent damage selectively on the highly emitting CNTs. In spite of turn-on field increase, emission images was showed remarkably uniform after oxygen trimming.

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Semantic Image Annotation and Retrieval in Mobile Environments (모바일 환경에서 의미 기반 이미지 어노테이션 및 검색)

  • No, Hyun-Deok;Seo, Kwang-won;Im, Dong-Hyuk
    • Journal of Korea Multimedia Society
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    • v.19 no.8
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    • pp.1498-1504
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    • 2016
  • The progress of mobile computing technology is bringing a large amount of multimedia contents such as image. Thus, we need an image retrieval system which searches semantically relevant image. In this paper, we propose a semantic image annotation and retrieval in mobile environments. Previous mobile-based annotation approaches cannot fully express the semantics of image due to the limitation of current form (i.e., keyword tagging). Our approach allows mobile devices to annotate the image automatically using the context-aware information such as temporal and spatial data. In addition, since we annotate the image using RDF(Resource Description Framework) model, we are able to query SPARQL for semantic image retrieval. Our system implemented in android environment shows that it can more fully represent the semantics of image and retrieve the images semantically comparing with other image annotation systems.

Structural Analysis Simulation of Cantilever Shaped Piezoelectric Energy Harvester Using COMSOL Multiphysics (COMSOL Multiphysics를 활용한 캔틸레버 형태의 압전 에너지 하베스터 구조 해석 시뮬레이션)

  • Kwak, Min Sub;Hwang, Geon-Tae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.34 no.6
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    • pp.416-425
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    • 2021
  • In the 4th industrial age, electronic devices are becoming smaller and lighter with a low power consumption to overcome spatial limitation. The piezoelectric energy harvesters can convert mechanical kinetic energy into electric energy; thus, enabling the operation of small electronic devices. Recently, various piezoelectric harvesters have been reported and the electric output from these harvesters could be anticipated by theoretical analysis methods. For example, COMSOL Multiphysics software provides a theoretical simulation of piezoelectric effect with a combination of mechanical and electrical phenomena in the piezoelectric materials. This article introduces a brief modeling of piezoelectric harvester to investigate mechanical stress and electrical output of harvesting devices by the COMSOL Multiphysics software.

A Study on the ESS Construction and Proper Operation Considering the Load Characteristics of the Distribution Logistics Facilities (유통물류시설 부하특성을 고려한 ESS 구축 및 적정 운영 방안에 관한 연구)

  • Heo, Donghyeok;Choi, Okhwan;Kwon, Dongmyeong
    • Journal of Energy Engineering
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    • v.28 no.2
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    • pp.36-46
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    • 2019
  • Through the application of ESS-based fusion products to the demonstration site of the urban distribution logistics facilities for designing the peak control and the substitution before the emergency generator operation by product application and the effective application method by the product application and the data analysis by overcoming the spatial limitation of ESS installation and distribution, And the expansion of distribution and logistics facilities.

Acquisition of Watershed-based Pollution Source Information using Spatial Distributed Geo-Information (분포형 공간정보를 이용한 유역단위 오염원정보 구축)

  • Bae, Myoung-Soon;Ha, Sung-Ryong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.4
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    • pp.215-223
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    • 2006
  • The Total Maximum Daily Load(TMDL) Act just implemented as a new tool of watershed based water quality management, in Korea. Thus, there are a number of pending questions to resolve for successful settlement of the TMDL. The allocation of pollution source is a exceedingly sensitive issue on local development planning. The simple area-based allocation (SAA) is conventional method to allocate the administrational pollution information to watershed based information. The SAA has a limitation that it can't consider the characteristics of spatial distribution of pollution source and it has caused more uncertainty of TMDL. This study was performed to reduce the uncertainty of watershed-based pollution information using the spatial distribution-based allocation(SDA). In the specific area where pollution source is concentrated such as urbanized region, it has been certified that SDA could reduce a tolerance of pollution information dramatically. As a result of study, SDA is expected a effective tool for TMDL and to solve the conflict between development and protection.

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Evaluation of MR-SENSE Reconstruction by Filtering Effect and Spatial Resolution of the Sensitivity Map for the Simulation-Based Linear Coil Array (선형적 위상배열 코일구조의 시뮬레이션을 통한 민감도지도의 공간 해상도 및 필터링 변화에 따른 MR-SENSE 영상재구성 평가)

  • Lee, D.H.;Hong, C.P.;Han, B.S.;Kim, H.J.;Suh, J.J.;Kim, S.H.;Lee, C.H.;Lee, M.W.
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.245-250
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    • 2011
  • Parallel imaging technique can provide several advantages for a multitude of MRI applications. Especially, in SENSE technique, sensitivity maps were always required in order to determine the reconstruction matrix, therefore, a number of difference approaches using sensitivity information from coils have been demonstrated to improve of image quality. Moreover, many filtering methods were proposed such as adaptive matched filter and nonlinear diffusion technique to optimize the suppression of background noise and to improve of image quality. In this study, we performed SENSE reconstruction using computer simulations to confirm the most suitable method for the feasibility of filtering effect and according to changing order of polynomial fit that were applied on variation of spatial resolution of sensitivity map. The image was obtained at 0.32T(Magfinder II, Genpia, Korea) MRI system using spin-echo pulse sequence(TR/TE = 500/20 ms, FOV = 300 mm, matrix = $128{\times}128$, thickness = 8 mm). For the simulation, obtained image was multiplied with four linear-array coil sensitivities which were formed of 2D-gaussian distribution and the image was complex white gaussian noise was added. Image processing was separated to apply two methods which were polynomial fitting and filtering according to spatial resolution of sensitivity map and each coil image was subsampled corresponding to reduction factor(r-factor) of 2 and 4. The results were compared to mean value of geomety factor(g-factor) and artifact power(AP) according to r-factor 2 and 4. Our results were represented while changing of spatial resolution of sensitivity map and r-factor, polynomial fit methods were represented the better results compared with general filtering methods. Although our result had limitation of computer simulation study instead of applying to experiment and coil geometric array such as linear, our method may be useful for determination of optimal sensitivity map in a linear coil array.