• 제목/요약/키워드: specific field

검색결과 3,177건 처리시간 0.025초

DEVELOPMENT OF SUPER WIDE SPREADER FOR DIRECT RICE SOWING IN WET PADDY FIELD

  • Kota Motobayashi;Yukio Yaji;Kim, Shoichi ura
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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    • pp.999-1008
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    • 1996
  • The development and improvement of the originally designed direct rice sowing machine were carried out for the specific purpose of saving labor and increasing the efficiency of field operations in rice cultivation in the northern part of Japan. the prototype super wide spreader has a unique mechanism which propels rice seeds by compressed air and spreads them from the pivoting nozzle while the machine is in motion. The effective field capacity of sowing operation is about 6 ha/h. This spreader can also handle granular chemicals such as fertilizers, herbicides, pesticides and insecticides.

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Near-Field Imaging of Graphene

  • 권혁상;김덕수;김지환
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.127-127
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    • 2012
  • We carried out the high-resolution dielectric mapping of graphenes on $SiO_2$/Si substrate, using the scattering Apertureless Near-Field Scanning Optical Microscopy (s-ANSOM) in both visible (633 nm) and infrared (3.6 um) wavelengths. In the visible wavelength, the dielectric contrasts are almost proportional to the number of the graphene layers, which indicates that the near-field interaction between the tip and individual graphene layers leads to an image charge oscillation in two-dimension. In the infrared region, on the other hand, we observe unique layer-specific contrasts that do not linearly increase with number of layers. It is attributed to the layer-dependent band- structure of graphenes.

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Assessment on Natural Frequencies of Structures using Field Measurement and FE Analysis

  • Kim, Do Hyun;Kim, Ji Young
    • 국제초고층학회논문집
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    • 제3권4호
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    • pp.305-310
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    • 2014
  • Wind-induced responses of a structure are often evaluated through dynamic analysis, where measured wind forces obtained from a wind-tunnel test and dynamic properties obtained from a FE (Finite Element) model are utilized. However, the FE model generally shows considerable discrepancies in the estimation of natural frequencies compared to field measurements due to some assumptions and simplifications. In this paper, a calibration method that can improve the estimation of natural frequencies in the FE model is proposed, and specific cases are studied for its validity with comparison to the field measurement results.

Study on Oriental Medicine Industry Development in Gyeongsangbukdo

  • Seo, Min-Jun
    • Journal of Evidence-Based Herbal Medicine
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    • 제3권1호
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    • pp.19-23
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    • 2010
  • Gyeongsangbukdo is nation's leading producer of medicinal crop. Based on this, Gyeongbuk-specific measures for the development of oriental medicine industry is proposed. The aim is the development of oriental medicine industry and regional economic in Gyeongbuk. Production, research and development, manufacturing, distribution are constructed in industrial cluster. And each step need a quality control strictly. In production field, make the seed valley of medicinal crop and Good Agricultural Practice park. In research and development field, study on efficacy of oriental medicine with Good Laboratory Practice. In manufacturing field, make industrial park for foods, dietary supplements and drugs with Good Manufacturing Practice. In distribution field, supports advanced distribution program with Good Supply Practice.

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A METHOD OF COMPUTING THE CONSTANT FIELD OBSTRUCTION TO THE HASSE PRINCIPLE FOR THE BRAUER GROUPS OF GENUS ONE CURVES

  • Han, Ilseop
    • 대한수학회지
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    • 제53권6호
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    • pp.1431-1443
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    • 2016
  • Let k be a global field of characteristic unequal to two. Let $C:y^2=f(x)$ be a nonsingular projective curve over k, where f(x) is a quartic polynomial over k with nonzero discriminant, and K = k(C) be the function field of C. For each prime spot p on k, let ${\hat{k}}_p$ denote the corresponding completion of k and ${\hat{k}}_p(C)$ the function field of $C{\times}_k{\hat{k}}_p$. Consider the map $$h:Br(K){\rightarrow}{\prod\limits_{\mathfrak{p}}}Br({\hat{k}}_p(C))$$, where p ranges over all the prime spots of k. In this paper, we explicitly describe all the constant classes (coming from Br(k)) lying in the kernel of the map h, which is an obstruction to the Hasse principle for the Brauer groups of the curve. The kernel of h can be expressed in terms of quaternion algebras with their prime spots. We also provide specific examples over ${\mathbb{Q}}$, the rationals, for this kernel.

Research Ethics in the Aviation Service Industry

  • Soyeon PARK
    • 연구윤리
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    • 제5권1호
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    • pp.7-11
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    • 2024
  • Purpose: This study seeks to discuss research ethics, not only the academic honesty and sincerity that researchers who study aviation services academically should have, but also the direction of the moral aspects that are fundamentally required as researchers. Additionally, this study seeks to examine the realistic problems of research related to the aviation service industry, a field of social science. Lastly, focusing on research ethics in the aviation service field, we will look at the theoretical background and the problems in the actual research field, and draw implications based on this. Research design, data and methodology: This study conducted an exploratory study through a selection process based on research ethics topics and research ethics related to the aviation service industry. Results: Efforts to systematize research ethics in research areas related to the aviation service industry, which is a field of social science, require efforts to expand the scope of systematization of research ethics related to the aviation service industry by referring to systemization efforts in other academic fields. In addition, specific systemization efforts will be needed through cooperation between universities, research institutes, and academic organizations. Also, concrete systematization efforts will be needed through cooperation between universities and academic organizations.

Design and Analysis of Experimental Anechoic Chamber for Localization

  • Kim, Keon-Wook
    • 한국음향학회지
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    • 제31권4호
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    • pp.225-234
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    • 2012
  • The anechoic chamber is essential tool to measure the various acoustic parameters with high precision. The chamber provides the climate controlled indoor environments but requires the dedicated room at a great cost in order to isolate and absorb sound field. Provided the purpose of the chamber is specific to the experiments of sound localization, the performance requirements excluding free field can be alleviated for cost effective solution. This paper designs low cost and profile anechoic chamber based on acoustic pyramids and evaluates the performance specified by the Annex of ISO 3745. Data analysis is employed to measure the free and hemi-free field performance over five straight paths for working areas and four paths for non-working areas. The identical two measurement campaigns were conducted for free and hemi-free field chamber which is easily interchangeable by simple labor in this chamber design. In the working area with conventional speaker, the results of these analyses demonstrate that lab-designed anechoic chamber is in conformance with ISO 3745 for 250 Hz - 16 kHz one-third octave band at free field chamber and for 1 kHz - 16 kHz one-third octave band at hemi-free field chamber.

3.0 T MRI를 위한 Parallel-Transmission RF 코일 구조의 비교와 최적화 (Comparison and Optimization of Parallel-Transmission RF Coil Elements for 3.0 T Body MRI)

  • 오창현;이흥규;류연철;현정호;최혁진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.61-63
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    • 2007
  • In high field (> 3 T) MR imaging, the magnetic field inhomogeneity in the target object increases due to the nonuniform electro-magnetic characteristics and relatively high Larmor frequency. Especially in the body imaging, the effect causes more serious problems resulting in locally high SAR(Specific Absorption Ratio). In this paper, we propose an optimized parallel-transmission RF coil element structure and show the utility of the coil by FDTD simulations to overcome the unwanted effects. Three types of TX coil elements are tested to maximize the efficiency and their driving patterns(amplitude and phase) optimized to have adequate field homogeneity, proper SAR level, and sufficient field strength. For the proposed coil element of 25 cm ${\times}$ 8 cm loop structure with 12 channels for a 3.0 T body coil, the 73% field non-uniformity without optimization was reduced to about 26% after optimization of driving patterns. The experimental as well as simulation results show the utility of the proposed parallel driving scheme is clinically useful for (ultra) high field MRI.

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유한한 유전체 격자구조에서 필드패턴 분석을 위한 모드연구 (The Mode Analysis for field pattern analysis of a Finite Periodic Dielectric Structure)

  • 김민년
    • 한국산학기술학회논문지
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    • 제9권3호
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    • pp.645-648
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    • 2008
  • 본 논문은 유한한 유전체 격자구조 내부에 형성되는 모드를 좀 더 정확하게 계산함으로써 근거리, 원거리 방사 필드 패턴을 분석하고자 한다. 유전체 내부의 필드 분포는 TE 모드가 형성되는 것으로 가정하여 각 층의 필드를 경계조건을 이용하여 계산하였다. 결과적으로 유한한 유전체 격자구조에서 필드들은 모드들을 형성하며 형성되는 모드의 수는 격자구조의 구조적 특징에 따라 달라진다. 본 논문은 특정 주파수에서 유전체 내부에 형성된 모드와 이들의 필드 분포를 계산하였다. 또한 계산된 모드의 FFT를 이용하여 원거리 방사패턴도 계산하였다.

SPATIAL YIELD VARIABILITY AND SITE-SPECIFIC NITROGEN PRESCRIPTION FOR THE IMPROVED YIELD AND GRAIN QUALITY OF RICE

  • Lee Byun-Woo;Nguyen Tuan Ahn
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2005년도 국제학술회의
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    • pp.57-74
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    • 2005
  • Rice yield and protein content have been shown to be highly variable across paddy fields. In order to characterize this spatial variability of rice within a field, the two-year experiments were conducted in 2002 and 2003 in a large-scale rice field of $6,600m^2$ In year 2004, an experiment was conducted to know if prescribed N for site-specific fertilizer management at panicle initiation stage (VRT) could reduce spatial variation in yield and protein content of rice while increasing yield compared to conventional uniform N topdressing (UN, ,33 kg N/ha at PIS) method. The trial field was subdivided into two parts and each part was subjected to UN and VRT treatment. Each part was schematically divided in $10\times10m$ grids for growth and yield measurement or VRT treatment. VRT nitrogen prescription for each grid was calculated based on the nitrogen (N) uptake (from panicle initiation to harvest) required for target rice protein content of $6.8\%$, natural soil N supply, and recovery of top-dressed N fertilizer. The required N uptake for target rice protein content was calculated from the equations to predict rice yield and protein content from plant growth parameters at panicle initiation stage (PIS) and N uptake from PIS to harvest. This model equations were developed from the data obtained from the previous two-year experiments. The plant growth parameters for this calculation were predicted non-destructively by canopy reflectance measurement. Soil N supply for each grid was obtained from the experiment of year 2003, and N recovery was assumed to be $60\%$ according to the previous reports. The prescribed VRT N ranged from 0 to 110kg N/ha with average of 57kg/ha that was higher than 33kg/ha of UN. The results showed that VRT application successfully worked not only to reduce spatial variability of rice yield and protein content but also to increase rough rice yield by 960kg/ha. The coefficient of variation (CV) for rice yield and protein content was reduced significantly to $8.1\%\;and\;7.1\%$ in VRT from $14.6\%\;and\;13.0\%$ in UN, respectively. And also the average protein content of milled rice in VRT showed very similar value of target protein content of $6.8\%$. Although N use efficiency of VRT compared to UN was not quantified due to lack of no N control treatment, the procedure used in this paper for VRT estimation was believed to be reliable and promising method for managing within-field spatial variability of yield and protein content. The method should be received further study before it could be practically used for site-specific crop management in large-scale rice field.

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