• Title/Summary/Keyword: Regular field

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An Analysis of Electrical Characteristics for Bundled Conductor Configurations in Overhead Transmission Lines. (가공송전선로의 소도체 구성방식에 따른 전기적 특성 해석)

  • Jeong, Y.H.;Sohn, H.K.;Lee, H.K.;Cho, Y.K.;Sin, B.D.
    • Proceedings of the KIEE Conference
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    • 1998.11a
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    • pp.245-247
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    • 1998
  • Compacting of Overhead power transmission lines can be helpful in solving many problems, such as reduction of land and forest losses. decrease of the line's environmental impact zones, improvement of its electrical performance. And in overhead transmission lines, regular polygon configuration of bundled conductors are considered and adopted. This papers are compared to subconductor surface charges and electric field gradients, line parameters, natural capacities for regular polygon and modified configurations in 345kV 4 bundle 2 circuits horizontal type transmission lines.

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Adaptive Re-reflecting Wave Control In Plunger Type Wave Maker System: Experiments In Two Dimensional Wave Basin

  • Park, Gun-Il;Kim, Ki-Jung;Park, Jae-Woong;Lee, Jin-Ho
    • Journal of Ship and Ocean Technology
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    • v.7 no.1
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    • pp.13-18
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    • 2003
  • The control performances for active re-reflecting wave control suggested in the previous paper have been verified in cases of regular and irregular waves in a real two dimensional wave basin. For regular waves, the control performances are investigated in terms of reflection coefficients, expected amplitudes of propagating waves and wave absorbing capabilities after cessation of wave generation, compared with those of no-control cases. For irregular waves similar verification procedures were adopted. Though there are certain constraints due to the geometrical non-linearity of wave maker and certain nonlinear characteristics due to the near field and gravity waves these experiments show that the control logic could be useful in realizing re-reflecting wave control in conditions of real wave basin.

Dynamic response characteristics of an innovative turretless low motion FPSO hull in central GoM ultra-deep waters

  • Zou, Jun
    • Ocean Systems Engineering
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    • v.12 no.2
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    • pp.173-223
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    • 2022
  • In oil and gas industry, FPSO concept is the most popular hull form and ship shaped hull form dominants the FPSO market. Only a non-ship-shaped hull in operations with minor market shares is the cylindrical FPSO hull with medium to small storage capability. To add contracting options and competitions to reduce field development costs, an innovative turretless low motion hull, eco-FPSO, with 1MM bbls oil storage capacity and suitable for installing topsides modulars and equipping with regular SCRs, was first introduced in Zou (2020a). Dynamic characteristic responses of the eco-FPSO compared to the traditional SS-FPSO hull and DD-Semi platform are presented and discussed in this paper, suitability and feasibility of the proposed hull have been demonstrated and validated through extensive analyses in 10-yrp, 100-yrp and 1,000-yrp hurricanes in ultra-deepwater central GoM.

Comparative Analysis of the Difference in the Midgut Microbiota between the Laboratory Reared and the Field-caught Populations of Spodoptera litura

  • Pandey, Neeti;Rajagopal, Raman
    • Microbiology and Biotechnology Letters
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    • v.47 no.3
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    • pp.423-433
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    • 2019
  • Midgut microbiota is known to play a fundamental role in the biology and physiology of the agricultural pest, Spodoptera litura. This study reports the difference in the larval midgut microbiota of field-caught and laboratory-reared populations of S. litura by performing 16S rDNA amplicon pyrosequencing. Field populations for the study were collected from castor crops, whereas laboratory-reared larvae were fed on a regular chickpea based diet. In total, 23 bacterial phylotypes were observed from both laboratory-reared and field-caught caterpillars. Fisher's exact test with Storey's FDR multiple test correction demonstrated that bacterial genus, Clostridium was significantly abundant (p < 0.05) in field-caught larvae of S. litura as compared to that in the laboratory-reared larvae. Similarly, bacterial genera, such as Bradyrhizobium, Burkholderia, and Fibrisoma were identified (p < 0.05) predominantly in the laboratory-reared population. The Bray-Curtis dissimilarity matrix depicted a value of 0.986, which exhibited the maximum deviation between the midgut microbiota of the laboratory-reared and field-caught populations. No significant yeast diversity was seen in the laboratory-reared caterpillars. However, two yeast strains, namely Candida rugosa and Cyberlindnera fabianii were identified by PCR amplification and molecular cloning of the internal transcribed space region in the field-caught caterpillars. These results emphasize the differential colonization of gut residents based on environmental factors and diet.

Suspended Sediment Concentrations over Ripples for Waves (파랑존재시 해저 모래결위의 부유사 농도분포)

  • Kim, Hyo-Seop;Kim, Tae-Hyeong
    • Journal of Korea Water Resources Association
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    • v.33 no.2
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    • pp.181-193
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    • 2000
  • This paper presents the flow and the suspended sediment movement over ripples for oscillatory flows. A new numerical model system is developed, and applied to a laboratory experimental condition of regular waves and a fictitious condition of irregular waves. The flow field is obtained from a programme proposed by Kim et. al.(1994), which is a modified version of SOLA based on SMAC scheme. The sub-model solves the continuity and Reynolds momentum equations in the x-z plane. The wave orbital velocities, shear stresses, and pressure are all reasonably reproduced by the model. The model results on the vertical velocity component show good agreement with the measurements. The suspended sediment transport sub-model is newly set up to solve the advection-diffusion equation of suspended sediment using a split method, and involving a special shear entrainment from the whole ripple surface. The calculated suspended sediment concentrations for regular waves show reasonable agreement with measurements at Deltaflume. The model results for random waves show that the suspended sediment concentration is higher than those for regular waves and that the sediment diffuses higher than for regular waves with the significant wave height and the peak wave period of the irregular waves.

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Design of High School Software AI Education Model in IoT Environment (사물인터넷 환경에서의 고등학교 SW·AI 교육 모델 설계)

  • Keun-Ho Lee;JungSoo Han
    • Journal of Internet of Things and Convergence
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    • v.9 no.1
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    • pp.49-55
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    • 2023
  • The evolution of new digital technologies is progressing rapidly. In particular, many changes in software and artificial intelligence are progressing rapidly in the field of education. The Ministry of Education is planning an educational program by linking software and artificial intelligence regular curriculum. Before applying it to regular subjects, various software and artificial intelligence related experience camps are being promoted. This study aims to construct an educational model for software and artificial intelligence education programs for high school students based on new digital technology. By expanding and distributing software and artificial intelligence education, we aim to enhance the basic capabilities of software and artificial intelligence for high school students. I would like to define the concept of software and artificial intelligence in high school and propose a model that links software and artificial intelligence learning factors to the regular curriculum.

Analytic Model for Concentration Deficit Profile Caused by a Large Vegetated Area (녹지의 대기정화효과 분석을 위한 해석적 대기확산모델의 유도)

  • 김석철
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.5
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    • pp.539-544
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    • 2000
  • A simple analytic model is proposed here to analyze the concentration deficit field caused by a large area of vegetated area. With non-dimensional deposition velocity chosen as small parameter, the regular perturbation method is exploited to derive the mass balance equation and the dynamic equations for the concentration deficit field, Analytic solutions to those equations are obtained in a closed form for several cases of interest, assuming that the concentration field is stationary and the plume can be nicely approximated as Gaussian for a point source. The results suggest that quite a negligible fraction (less than 1%) of the gaseous air pollutants emitted into the air is removed by the vegetated area of which width is 4 km in wind-wise direction, the typical dimension of the Restricted Development Zones around the metropolitan regions in South Korea.

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A study on the multiplier for finite field GF($2^m$) (GF($2^m$)상의 승산기 구성에 관한 연구)

  • Won, D.H.;Kim, B.C.
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.845-849
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    • 1987
  • Finite field arithmetic logic is central in the implementation of Reed-Solomon coders and in some cryptographic algorithms. There is a need for good multiplication and basis conversion algorithms. In this paper, a new multiplication circuit is developed for the finite field GF($2^m$) based on a conventional basis. It is composed of AND gates and EXCLUSIVE-OR gates and is regular, simple, expandable and therefore, naturally suitable for VLSI implementations.

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An Efficient Analysis of Unbounded Scattering Field Using Three Dimensional Boundary Element Method (3차원 경계요소법을 이용한 무경계 산란장의 효율적 해석)

  • 박동희;김정기
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.5 no.3
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    • pp.14-21
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    • 1994
  • In this paper, a numerical method to be obtain the radar cross section(RCS) of three- dimensional bodies with arbitrary geometry and material compositions on the electromagnetic field with arbitrary incident angle is described. The RCS is obtained by solving the individual surface integral equation about multilayers scatterer using the three-dimensional bonudary element method(BEM). To show propriety and usefulness as to the three-dimensional BEM in this paper, the choice of a geometry is a multi-regular hexahedron and multi-right-angled hexahedron out of oblique incident electric field, and is considered to apply to every condition with loss sufficiently.

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Development of Photon Therapy Planning Treatment in Pilot Type (파일롯 형태의 광자선 치료계획장치 개발)

  • Choi, E.J.;Suh, T.S.;Youn, K.J.;Na, Y.J.;Suh, D.Y.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.176-179
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    • 1997
  • In this paper, We developed a radiation therapy planning system using photon beams. Firstly We accomplished simulation on the regular field. Then it has been modified step by step to handle the irregular field, wedge filter, and inhomogeneous field. This system is equipped with useful user interface and database. This system is implemented in Visual C++ as a window-based application program.

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