• 제목/요약/키워드: large(essential)

검색결과 1,616건 처리시간 0.032초

Experimental study on the correlation between measurement length and winding or twist pitch for magnetization loss occurring in CORC and TSTC

  • Ji-Kwang Lee;Jinwoo Han;Kyeongdal Choi;Woo-Seok Kim
    • 한국초전도ㆍ저온공학회논문지
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    • 제25권4호
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    • pp.40-44
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    • 2023
  • For high-temperature superconducting power applications that need large current capacity, a large current conductor manufactured using multiple superconducting tape is required. Conductors being studied for large currents capacity such as CORC, TSTC, and RACC have advantages and disadvantages, and in order to use these conductors in coil form and apply them to AC power devices, research on magnetization loss occurring in superconductors due to external magnetic fields is essential. To accurately measure magnetization loss in a conductor that is twisted by stacking straight conductors like TSTC, the correlation between the measuring system and the shape of the sample must be clearly known to accurately measure the loss. In this paper, we will confirm the difference in magnetization loss measurement values according to the correlation between the length of the pickup coil and the twist pitch of the sample in CORC and TSTC shapes, and review considerations for accurate magnetization loss measurement from the results.

IPS-TFT-LCDs Technology Trends

  • Tajima, Zenzo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.15-18
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    • 2004
  • Recent progress of the in-plane switching (IPS) TFT-LCD technologies is reviewed. We call the improved new technology 'advanced super IPS TFT-LCD(AS-IPS)'. After suppressing the viewing angle dependency of essential display characteristics, recent brightness, viewing angle and motion picture quality has been highly improved. The stage is now introducing it into consumer information appliance for higher display performances, by which we could open a large size digital LCD TVs application.

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고 정밀 항공우주 유동해석 및 설계를 위한 공력계산 툴 (Essential Computational Tools for High-Fidelity Aerodynamic Simulation and Design)

  • 김종암
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.33-36
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    • 2006
  • As the computing environment is rapidly improved, the interests of CFD are gradually focused on large-scale computation over complex geometry. Keeping pace with the trend, essential computational tools to obtain solutions of complex aerospace flow analysis and design problems are examined. An accurate and efficient flow analysis and design codes for large-scale aerospace problem are presented in this work. With regard to original numerical schemes for flow analysis, high-fidelity flux schemes such as RoeM, AUSMPW+ and higher order interpolation schemes such as MLP (Multi-dimensional Limiting Process) are presented. Concerning the grid representation method, a general-purpose basis code which can handle multi-block system and overset grid system simultaneously is constructed. In respect to design optimization, the importance of turbulent sensitivity is investigated. And design tools to predict highly turbulent flows and its sensitivity accurately by fully differentiating turbulent transport equations are presented. Especially, a new sensitivity analysis treatment and geometric representation method to resolve the basic flow characteristics are presented. Exploiting these tools, the capability of the proposed approach to handle complex aerospace simulation and design problems is tested by computing several flow analysis and design problems.

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Metal forming analysis using meshfree-enriched finite element method and mortar contact algorithm

  • Hu, Wei;Wu, C.T.
    • Interaction and multiscale mechanics
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    • 제6권2호
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    • pp.237-255
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    • 2013
  • In this paper, a meshfree-enriched finite element method (ME-FEM) is introduced for the large deformation analysis of nonlinear path-dependent problems involving contact. In linear ME-FEM, the element formulation is established by introducing a meshfree convex approximation into the linear triangular element in 2D and linear tetrahedron element in 3D along with an enriched meshfree node. In nonlinear formulation, the area-weighted smoothing scheme for deformation gradient is then developed in conjunction with the meshfree-enriched element interpolation functions to yield a discrete divergence-free property at the integration points, which is essential to enhance the stress calculation in the stage of plastic deformation. A modified variational formulation using the smoothed deformation gradient is developed for path-dependent material analysis. In the industrial metal forming problems, the mortar contact algorithm is implemented in the explicit formulation. Since the meshfree-enriched element shape functions are constructed using the meshfree convex approximation, they pose the desired Kronecker-delta property at the element edge thus requires no special treatments in the enforcement of essential boundary condition as well as the contact conditions. As a result, this approach can be easily incorporated into a conventional displacement-based finite element code. Two elasto-plastic problems are studied and the numerical results indicated that ME-FEM is capable of delivering a volumetric locking-free and pressure oscillation-free solutions for the large deformation problems in metal forming analysis.

Leveraging Deep Learning and Farmland Fertility Algorithm for Automated Rice Pest Detection and Classification Model

  • Hussain. A;Balaji Srikaanth. P
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권4호
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    • pp.959-979
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    • 2024
  • Rice pest identification is essential in modern agriculture for the health of rice crops. As global rice consumption rises, yields and quality must be maintained. Various methodologies were employed to identify pests, encompassing sensor-based technologies, deep learning, and remote sensing models. Visual inspection by professionals and farmers remains essential, but integrating technology such as satellites, IoT-based sensors, and drones enhances efficiency and accuracy. A computer vision system processes images to detect pests automatically. It gives real-time data for proactive and targeted pest management. With this motive in mind, this research provides a novel farmland fertility algorithm with a deep learning-based automated rice pest detection and classification (FFADL-ARPDC) technique. The FFADL-ARPDC approach classifies rice pests from rice plant images. Before processing, FFADL-ARPDC removes noise and enhances contrast using bilateral filtering (BF). Additionally, rice crop images are processed using the NASNetLarge deep learning architecture to extract image features. The FFA is used for hyperparameter tweaking to optimise the model performance of the NASNetLarge, which aids in enhancing classification performance. Using an Elman recurrent neural network (ERNN), the model accurately categorises 14 types of pests. The FFADL-ARPDC approach is thoroughly evaluated using a benchmark dataset available in the public repository. With an accuracy of 97.58, the FFADL-ARPDC model exceeds existing pest detection methods.

A comparison of ATR-FTIR and Raman spectroscopy for the non-destructive examination of terpenoids in medicinal plants essential oils

  • Rahul Joshi;Sushma Kholiya;Himanshu Pandey;Ritu Joshi;Omia Emmanuel;Ameeta Tewari;Taehyun Kim;Byoung-Kwan Cho
    • 농업과학연구
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    • 제50권4호
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    • pp.675-696
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    • 2023
  • Terpenoids, also referred to as terpenes, are a large family of naturally occurring chemical compounds present in the essential oils extracted from medicinal plants. In this study, a nondestructive methodology was created by combining ATR-FT-IR (attenuated total reflectance-Fourier transform infrared), and Raman spectroscopy for the terpenoids assessment in medicinal plants essential oils from ten different geographical locations. Partial least squares regression (PLSR) and support vector regression (SVR) were used as machine learning methodologies. However, a deep learning based model called as one-dimensional convolutional neural network (1D CNN) were also developed for models comparison. With a correlation coefficient (R2) of 0.999 and a lowest RMSEP (root mean squared error of prediction) of 0.006% for the prediction datasets, the SVR model created for FT-IR spectral data outperformed both the PLSR and 1 D CNN models. On the other hand, for the classification of essential oils derived from plants collected from various geographical regions, the created SVM (support vector machine) classification model for Raman spectroscopic data obtained an overall classification accuracy of 0.997% which was superior than the FT-IR (0.986%) data. Based on the results we propose that FT-IR spectroscopy, when coupled with the SVR model, has a significant potential for the non-destructive identification of terpenoids in essential oils compared with destructive chemical analysis methods.

TRNSYS 프로그램을 이용한 대형쇼핑매장 에너지성능해석 및 지열시스템을 도입하는 경우 에너지절약 특성분석 (Analysis of Energy Performance & Energy Saving with Geothermal Heat Pump System Using TRNSYS Program in a Large Scale Shopping Store)

  • 홍원표
    • 조명전기설비학회논문지
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    • 제29권1호
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    • pp.47-56
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    • 2015
  • Energy consumption in buildings is currently a real problem. That is why both assessment of energy performance and effective energy management including renewable energy system are essential. Thus, this paper focuses on a case study to analyze the energy performance and cooling & heating energy saving of a large scale shopping store in Daejeon city. The reference building is simulated by using TRNSYS dynamic simulation tool to examine its annual energy consumption. For annual energy analysis of building, one year energy consumption is surveyed in the field. The related study is carried out in large scale shopping store to investigate the energy consumption and energy use trend of heating, cooling, hot water, lighting, ventilation, equipments and other. The evaluation of energy performance of the geothermal heat pump system installed in a large scale shopping store is also analyzed by TRNSYS tool. From simulation results, it evaluated that the geothermal heat pump system is effective energy savings method in large scale shopping store.

IT서비스 대·중소기업 동반성장 전략 연구 (A Study on Win-Win Growth Strategy for Large and Mid-sized IT Service Enterprises)

  • 김현수
    • 한국IT서비스학회지
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    • 제11권3호
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    • pp.177-190
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    • 2012
  • The purpose of this research is to find a better win-win growth strategy of Large and mid-sized IT service enterprises. Efficient win-win growth for large and mid-sized enterprises is essential for acquiring a solid global competitiveness in IT service industry. However, previous studies lack generalized and detailed findings, and therefore past strategies were based on fragmented analysis. To develop an efficient win-win growth for Large and mid-sized enterprises, global benchmarking and an in-depth analysis on deep-rooted problems in IT service industry has been conducted. Past and present policies on IT service industry have been reviewed based on desirable co-growth structure. Based on research, current policies are unable to support co-growth, and collaborative efforts between Large and mid-sized enterprises as well as square deals are necessary for win-win growth. A new policy paradigm has been derived and a roadmap for efficient co-growth strategy has been suggested. The results of this research can be used for building a better IT service industry polices. In future studies, a longitudinal analysis on the proposed co-growth strategy can be conducted.

유기재배 과원에서 큰검정풍뎅이 방제를 위한 기피 살충자재 선발 (Screening of Essential Oil Repellents against the Organic Pear Pest Holotrichia parallela (Coleoptera: Scarabaeidae))

  • 송장훈;압둘알림;최으뜸;최덕수;서호진
    • 한국유기농업학회지
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    • 제26권2호
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    • pp.259-268
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    • 2018
  • The study investigated the efficacy of four different essential oils on the repellent responses of large black chafer (Holotrichia parallela) Motschulsky (Coleoptera: Scarabaeidae) in organic pear (Pyrus pyrifolia) orchards. Cinnamon, pine, peppermint, and eucalyptus oils were used, and the behavioral responses and repellent effects against H. parallela were investigated under laboratory and field conditions. Adult beetle responses to different oils were examined using a Y-tube olfactometer in the laboratory and four absorbent blocks with each oil in the field. The repellent responses rates of H. parallela were 100% for cinnamon oil; however, only 67% of adult beetles avoided peppermint and eucalyptus oil in the Y-tube olfactometer bioassay. In the field tests, the least damage to leaves was observed on trees treated with cinnamon oil, whereas the most damage was observed in the control (non-treated) trees and those treated with peppermint oil, followed by eucalyptus and pine oil. Therefore, cinnamon oil can be used as a repellent to avoid damage form large black chafers in organic pear orchards.

LARGE EDDY SIMULATION OF TURBULENT CHANNEL FLOW USING ALGEBRAIC WALL MODEL

  • MALLIK, MUHAMMAD SAIFUL ISLAM;UDDIN, MD. ASHRAF
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제20권1호
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    • pp.37-50
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    • 2016
  • A large eddy simulation (LES) of a turbulent channel flow is performed by using the third order low-storage Runge-Kutta method in time and second order finite difference formulation in space with staggered grid at a Reynolds number, $Re_{\tau}=590$ based on the channel half width, ${\delta}$ and wall shear velocity, $u_{\tau}$. To reduce the calculation cost of LES, algebraic wall model (AWM) is applied to approximate the near-wall region. The computation is performed in a domain of $2{\pi}{\delta}{\times}2{\delta}{\times}{\pi}{\delta}$ with $32{\times}20{\times}32$ grid points. Standard Smagorinsky model is used for subgrid-scale (SGS) modeling. Essential turbulence statistics of the flow field are computed and compared with Direct Numerical Simulation (DNS) data and LES data using no wall model. Agreements as well as discrepancies are discussed. The flow structures in the computed flow field have also been discussed and compared with LES data using no wall model.