• 제목/요약/키워드: open field

검색결과 2,203건 처리시간 0.031초

Design of Body RF Coil with Multiple Strips for Open MRI System by Pseudo Electric Dipole Radiation

  • 김경락;류승학;류연철;양형진;오창현
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 2002년도 제7차 학술대회 초록집
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    • pp.76-76
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    • 2002
  • Purpose: The purpose of this study is to optimize the configuration of body RF coil composed of 4 planar subcoils for low field open MRI. Method: Our low field RE coil is composed of 4 subcoils assumed to be located at both the bottom and top sides of permanent magnet. Each subcoils has 3 main strips. The coil system has mirror inversion symmetry. First, the currents on the strips are obtained by inductance calculation and circuit analysis, Second, all the strips are divided into line strip elements across the strips, the self Inductances of line strip elements and the mutual inductances among the line strip elements are calculated, and current distributions of strip are obtained by circuit analysis, where each strip is considered as parallel combination of line strip elements. Finally all the line strip elements are segmented, magnetic field has been calculated by pseudo electric dipole radiation method, where the current elements are regarded as pseudo electric dipole radiation sources. We have performed above procedures for various configurations of RE coil. The field homogeneity is calculated in the 25 cm DSV.

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재배방법이 참죽나무 잎의 생육 및 무기물 함량에 미치는 영향 (Effect of Culture Methods on Growth and Mineral Contents in Chinese Toon (Cedrela sinensis A. Juss))

  • 신용습;이문중;임양숙;이은숙;안준형;한윤열;임재하;박소득;채장희
    • 생물환경조절학회지
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    • 제21권4호
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    • pp.392-397
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    • 2012
  • 참죽나무 순채 조기생산을 위하여 하우스와 노지재배에서 생산된 잎의 무기성분을 분석한 결과는 다음과 같다. 참죽나무 순채의 생장속도는 노지에 비하여 하우스 재배에서 다소 빠른 경향이었고, 정아의 경우 초장, 가지수 등 생육과 생체 중, 엽록소 함량 등 품질은 노지와 하우스재배 처리 간 큰 차이가 없었다. 참죽나무 순채의 색도(a값)는 측아보다는 정아에서 적색도가 다소 높았으나 하우스와 노지재배 간에는 차이가 거의 없었다. 참죽나무 정아 및 측아의 pH는 5.7~6.2 정도였고 N 함량은 측아의 평균 $500.5mg{\cdot}kg^{-1}$에 비해 정아에서 3.1배 많았고, 노지재배($1,430mg{\cdot}kg^{-1}$)보다는 하우스 재배에서 1.2배 많았다. P, Ca, Mg 및 Fe 함량도 노지재배에 비하여 하우스 재배에서 유의성 있게 높았는데, P는 1.1배, Ca는 1.7배, Mg는 2.0배, Fe는 2.3배 정도 많았으나 K 함량은 하우스 재배의 $2.94mg{\cdot}kg^{-1}$에 비하여 노지재배에서 1.6배 많았다. Ascorbic acid 함량은 하우스 측아에서 $1,461mg{\cdot}kg^{-1}$으로 가장 높았고 노지 측아, 노지 정아, 하우스 정아 순이었다. 이상의 결과를 종합하면 고품질 참죽나무 순채 생산을 위해서 하우스 재배가 필요한 것으로 생각된다.

Implementations of Geographic Information Systems on Sewage Management for Water Resources Protection

  • Wu, Mu-Lin;Chen, Chiou-Hsiung;Chou, Wen-Shang;Huang, Hsiu-Lan
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1188-1190
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    • 2003
  • Taipei Watershed Management Bureau (WRATB) is a government agency entitled for water resources protection at two major watersheds in order to provide drinking water for about four millions population in Taipei on a sustainable basis. At WRATB, there are two major public sewage treatment facilities which can convert sewage in each watershed into an acceptable state before they were discharged into rivers. More than 82% of household wastewater have been collected and treated by the two public sewage systems. However, households at remote area still need more effective sewage management prescriptions. The objective of this paper is to implement geographic information systems in order to provide more effective approaches that sewage management can be easier and cost effective. ArcIMS was implemented for Internet browsing and map server of those sewage facilities on personal computers, laptop computers. In the open field, ArcPAD was implemented with personal digital assistant (PDA) such that compact flash type's global positioning systems (GPS) and digital camera can be utilized with PDA. All sewage facilities digital files were convert into ArcMap format files. MapObjects and visual BASIC were used to create sewage application modules to meet every single technician personal flavor. ASP.NET was implemented for Internet database manipulations of all sewage databases. Mobile GIS was the key component of GIS applications in the open field for sewage management on a basis of house by house. Houses at remote area, which can not cover by the two public sewage systems, were managed by PDA and laptop computers with GPS and digital camera. Sewage management at Taipei Watershed Management Bureau is easier both in the open field and in the office. Integration of GPS, GIS, and PDA makes sewage management in the open field much easier. ArcIMS, MapObjects, ASP.NET and visual BASIC make sewage management can be done in the office and over Internet.

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우울증(憂鬱症)모델 흰쥐에 대한 죽여(竹茹)와 St. John's Wort의 항우울효과(抗憂鬱效果)에 대한 비교 연구 (The effects of Bambusae Caulis and St. John's Wort in the chronic mild stress model of depression in rats)

  • 박세진;김종우;김현택;지상은;김운령;황의완
    • 동의신경정신과학회지
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    • 제15권2호
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    • pp.53-70
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    • 2004
  • Objective : This study was designed to assess the protective effects of Bambusae caulis and St. John's Wort on the animal model of depression, induced by chronic mild stress(CMS) Method : Male Wistar rats were used for this experiment. The subjects were divided into 4 groups ( 1. CMS-drugs: Bambusae caulis administered during CMS treatment, 2. CMS-drugs: St. John's Wort administered during CMS treatment, 3. CMS-vehicle: Water administered during CMS treatment, 4. normal control group without CMS treatment ). After 3 weeks of CMS treatment, they were executed open field test and weight, sucrose intake were measured. Result : 1. CMS Bambusae caulis group showed significant difference of locomotor activities and marginal difference of start latency in comparison with other groups in open field test. 2. There was no change of weights between CMS Bambusae caulis, St. John's Wort groups and CMS control group. 3. CMS St. John's Wort group showed upper level of sucrose intake than CMS Bambusae caulis group and CMS control group. Conclusion : These results suggest that Bambusae caulis may have protective antidepressant effects in CMS model rats. And these effects could be explained by the elevated locomotor activities in open field test.

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고흥항공센터의 전기장 환경 분석 (Electromagnetic Environment Analysis of Goheung Aviation Center)

  • 장경덕;김태윤;장재웅;민병희;조인경;문귀원
    • 항공우주기술
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    • 제12권1호
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    • pp.46-53
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    • 2013
  • 일반적으로 전자파 환경시험은 외부 전자기 환경의 영향을 배제하기 위하여 전자파 차폐룸에서 시험을 수행하지만, 시험체의 크기가 너무 크거나, 배기가스를 방출하는 등의 제약이 있을 경우 전자파 차폐룸에서 시험이 어려울 수 있으며, 야외 시험장을 이용할 수 밖에 없다. 야외 시험장은 측정 결과에 영향을 미칠 수 있는 전파 반사체, 전파 잡음 등이 시험장 내에 존재하지 않는 것이 이상적이지만 IT, 무선 통신 산업이 발달됨에 따라 기존의 야외 시험장은 수많은 생활전자파노이즈에 오염되어 있는 실정이다. 고흥 항공센터의 경우 도심과 떨어져 있고, 주변이 농경지로 둘러싸여 있어 전자파환경이 청정할 것으로 예상되며, 따라서 대형시험체의 전계강도를 측정할 수 있는 야외 시험장으로 활용이 가능할 수 있다. 이를 확인하기 위해 고흥 항공센터의 전자파환경을 측정하였으며, 30 MHz 이상의 주파수대역에서는 라디오, TV, 핸드폰 등 소스가 분명한 주파수를 제외하고는 대체적으로 깨끗한 결과를 보였으며 야외 시험장으로 좋은 역할을 할 수 있음을 확인하였다.

Patent Trend of Unmanned and Automated Agricultural Production - Open Field Operation -

  • Kim, YongJoo;Chung, SunOk;Lee, ChoongHan;Lee, DaeHyun;Lee, KyeongHwan
    • Agribusiness and Information Management
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    • 제6권1호
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    • pp.30-36
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    • 2014
  • This study was conducted to determine the major patent and analyze the patent trend of unmanned and automated agricultural production for the open field operation. As a result of conducting a search for patent applications related to these technologies, 1,080 valid patents were selected by evaluating the relevance of the patents and removing noise patents. As a result of the country-based analysis using the selected valid patents, it was found out that the largest number of patent applications were filed in the United States with 541 cases, followed by Japan with 326 cases, the European Union with 128 cases, and Korea with 85 cases. Upon classifying the valid patents into core technology, the path generation and tracking technology accounts for 33% with 353 cases; the implementing control with environmental condition technology accounts for 22% with 236 cases; the robot design technology accounts for 21% with 228 cases; the plant and environment sensing technology accounts for 19% with 206 cases; the yield and quality monitoring technology accounts for 5% with 58 cases. Finally, 10 core patents were selected by performing a patent index evaluation. The United States registered all of the 10 core patents. The results showed that Korea falls behind in the open field-related unmanned and automated agricultural production, compared to other developed agricultural countries.

제브라피쉬에서의 제주도 천연추출물의 항스트레스 효과 (Anti-stress Effects of Natural Products from Jeju Island in Zebrafish)

  • 이정원;이승헌
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2019년도 추계학술대회
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    • pp.85-85
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    • 2019
  • Objective: In this study, the anti-stress effects of extract of Hydrangeae Dulcis Folium (EHDF) or ethalonic extract of Opuntiaficus-indica (EOF) of natural extracts from Jeju Island were investigated. Methods: We performed measurement of whole-body cortisol level and behavioral experiments including the novel tank test (NTT) or the open field test (OFT) to assess stress responses in zebrafish. To induce physical stress, we used the net handling stress (NHS). Fish were treated with EOF or EHDF for 6 min before they were exposed to stress. And then, we sacrificed fish for collecting body fluid from whole-body or conducted behavioural tests, including novel tank test and open field test, were evaluated to observe anxiety-like behaviours and locomotion. We used the cortisol enzyme-linked immunoassay kit to measure the amount of cortisol in each zebrafish sample. Results: The results indicate that increased anxiety-like behaviours in novel tank test and open field test under stress were prevented by treatment with both EOF and EHDF (P < 0.05). Moreover, compared with the unstressed group, which was not treated with NHS, the whole-body cortisol level was significantly increased by treatment with NHS. Compared with the NHS-treated stressed control group, pre-treatment with each EHDF and EOF for 6 min significantly prevented the NHS-increased whole-body cortisol level (P < 0.05). Conclusions: In conclusion these results suggest that both EOF and EHDF pretreatment may prevent stress responses and that its mechanism of action may be related to its positive effects on cortisol release.

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지도학습 알고리즘 기반 3D 노지 작물 구분 모델 개발 (Development of 3D Crop Segmentation Model in Open-field Based on Supervised Machine Learning Algorithm)

  • 정영준;이종혁;이상익;오부영;;서병훈;김동수;서예진;최원
    • 한국농공학회논문집
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    • 제64권1호
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    • pp.15-26
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    • 2022
  • 3D open-field farm model developed from UAV (Unmanned Aerial Vehicle) data could make crop monitoring easier, also could be an important dataset for various fields like remote sensing or precision agriculture. It is essential to separate crops from the non-crop area because labeling in a manual way is extremely laborious and not appropriate for continuous monitoring. We, therefore, made a 3D open-field farm model based on UAV images and developed a crop segmentation model using a supervised machine learning algorithm. We compared performances from various models using different data features like color or geographic coordinates, and two supervised learning algorithms which are SVM (Support Vector Machine) and KNN (K-Nearest Neighbors). The best approach was trained with 2-dimensional data, ExGR (Excess of Green minus Excess of Red) and z coordinate value, using KNN algorithm, whose accuracy, precision, recall, F1 score was 97.85, 96.51, 88.54, 92.35% respectively. Also, we compared our model performance with similar previous work. Our approach showed slightly better accuracy, and it detected the actual crop better than the previous approach, while it also classified actual non-crop points (e.g. weeds) as crops.

농산물 재배 방식에 따른 사회, 경제, 환경 영향 비교 - 농산물 소득조사 자료와 스마트팜 실태조사 보고서를 기반으로 - (Comparison of Social, Economic, and Environmental Impacts depending on Cultivation Methods - Based on Agricultural Income Survey Data and Smart Farm Survey Reports -)

  • 이지민;김태곤
    • 농촌계획
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    • 제29권4호
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    • pp.127-135
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    • 2023
  • This study examined the impact of changes in agricultural production methods on society, the economy, and the environment. While traditional open-field farming relied heavily on natural conditions, modern approaches, including greenhouse and smart farming, have emerged to mitigate the effects of climate and seasonal variations. Facility horticulture has been on the rise since the 1990s, and recently, there has been a growing interest in smart farms due to reasons such as climate change adaptation and food security. We compared open-field spinach and greenhouse spinach using agricultural income survey data, and we also compared greenhouse tomato cultivation with smart farming tomato cultivation, utilizing data from the smart farm survey reports. The economic results showed that greenhouse spinach increased yield by 25.8% but experienced a 29% decrease in income due to equipment depreciation. In the case of tomato production in smart farms, both yield and income increased by 36-39% and 34-46%, respectively. In terms of environmental impact, we also compared fertilizer and energy usage. It was found that greenhouse spinach used 29% less fertilizer but 14% more energy compared to open-field spinach. Smart farming for tomatoes saw a negligible decrease in electricity and fuel costs. Regarding the social impact, greenhouse spinach reduced labor hours by 31%, and the introduction of smart farming for tomatoes led to an average 11% reduction in labor hours. This reduction is expected to have a positive effect on sustainable farming. In conclusion, the transition from open-field to greenhouse cultivation and from greenhouse cultivation to smart farming appears to yield positive effects on the economy, environment, and society. Particularly, the reduction in labor hours is beneficial and could potentially contribute to an increase in rural populations.

AKARI DEEP FIELD SOUTH: SPECTROSCOPIC OBSERVATIONS OF INFRARED SOURCES

  • Sedgwick, Chris;Serjeant, Stephen;Pearson, Chris;Matsuura, Shuji;Shirahata, Mai;Matsuhara, Hideo;Marchetti, Lucia;White, Glenn J.;Vaccari, Mattia;Baronchelli, Ivano;Rodighiero, Giulia;Hadsukade, Bunyo;Clements, David L.;Amber, Simon
    • 천문학논총
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    • 제32권1호
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    • pp.281-285
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    • 2017
  • We present a summary of our spectroscopic redshift catalogue of 404 sources in the AKARI Deep Field South (ADF-S). We have used the AAOmega spectrograph to target mid-infrared and far-infrared sources selected primarily from AKARI observations in this field for which we were able to obtain optical counterparts. Our sources with identified redshifts include 316 with $H{\alpha}$ detections at $z{\leq}0.345$ and 15 sources at z > 1 with MgII or $Ly{\alpha}$ emission lines. About 13% of our $z{\leq}0.345$ sources are dominated by active galactic nuclei (AGN) emission, although many show emission from both star formation and AGNs. The median Balmer decrement is 5.9. Ultra-luminous infrared galaxies (ULIRGs) were found only in the higher-redshift sources. Optical and near infrared data will be available shortly, enabling calibration of the line luminosities and spectral energy distribution (SED) fitting for these sources.