• Title/Summary/Keyword: radio/high frequency

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Use of Unmanned Aerial Vehicle for Multi-temporal Monitoring of Soybean Vegetation Fraction

  • Yun, Hee Sup;Park, Soo Hyun;Kim, Hak-Jin;Lee, Wonsuk Daniel;Lee, Kyung Do;Hong, Suk Young;Jung, Gun Ho
    • Journal of Biosystems Engineering
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    • v.41 no.2
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    • pp.126-137
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    • 2016
  • Purpose: The overall objective of this study was to evaluate the vegetation fraction of soybeans, grown under different cropping conditions using an unmanned aerial vehicle (UAV) equipped with a red, green, and blue (RGB) camera. Methods: Test plots were prepared based on different cropping treatments, i.e., soybean single-cropping, with and without herbicide application and soybean and barley-cover cropping, with and without herbicide application. The UAV flights were manually controlled using a remote flight controller on the ground, with 2.4 GHz radio frequency communication. For image pre-processing, the acquired images were pre-treated and georeferenced using a fisheye distortion removal function, and ground control points were collected using Google Maps. Tarpaulin panels of different colors were used to calibrate the multi-temporal images by converting the RGB digital number values into the RGB reflectance spectrum, utilizing a linear regression method. Excess Green (ExG) vegetation indices for each of the test plots were compared with the M-statistic method in order to quantitatively evaluate the greenness of soybean fields under different cropping systems. Results: The reflectance calibration methods used in the study showed high coefficients of determination, ranging from 0.8 to 0.9, indicating the feasibility of a linear regression fitting method for monitoring multi-temporal RGB images of soybean fields. As expected, the ExG vegetation indices changed according to different soybean growth stages, showing clear differences among the test plots with different cropping treatments in the early season of < 60 days after sowing (DAS). With the M-statistic method, the test plots under different treatments could be discriminated in the early seasons of <41 DAS, showing a value of M > 1. Conclusion: Therefore, multi-temporal images obtained with an UAV and a RGB camera could be applied for quantifying overall vegetation fractions and crop growth status, and this information could contribute to determine proper treatments for the vegetation fraction.

A Study on the Use of Supplementary Teaching Materials and Implements in the High School Home Economics Education (고등학교 가정과 교육에서 보조학습 교재.교구의 활용실태 연구)

  • 조은경;김용숙
    • Journal of Korean Home Economics Education Association
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    • v.9 no.1
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    • pp.1-17
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    • 1997
  • This study was conducted to obtain basic materials to improve the teaching method of Home Economics by theoretically looking into the supplementary teaching materials or implements usable in teaching Costume History area. And based on these data, the types and the applications of the supplementary teaching materials or implements highschool owned were examined. The subjects of this study were 111 Home Economics and Housework curriculum highschool teachers who give a lecture in the country by using self-administered questionnaires. SAS program was used to calculate frequency, percentage, average, standard deviation, and $\chi$(sup)2-test analysis. The results of the study were as follows; 1. Most of the highschool teachers used the school expenses for experiments in preparing the supplementary teaching materials or implements. 2. Of the supplementary teaching materials and implements concerning Costume History, visual implements such as slides and pictures were the mostly owned. CD and audio implements as cassette-tapes were not used. 3. Most of the teachers recognized the importance of the audio-visual teaching materials and implements concerning Costume History. 4. Among the audio-visual materials and implements concerning Costume History by which can be made by school teachers of Home Economics and Housework curriculum, the mostly used one was ‘cutting pictorials from magazines and newspapers’, and the next were ‘orbital materials’, and ‘copy the pictorials’, and the least was ‘recording from the radio’. 5. Most of the annual expenses assigned to the department of Home Economics was used in cooking practice, and the least of the expenses was assigned in buying audio-visual teaching materials and implements. 6. Time assigned to the area of Home Economics was for the most part one or two hours per week, and among this, time assigned to the history of western costume and the history ok korean costume was for the most part five to eight hours. 7. The areas that the highschool teachers felt difficulties mostly during clothing and textiles curriculum were ‘textiles’and the next were ‘knitting’, ‘western costume history’, and ‘korean clothing construction’. 8. The difficulties the highschool teachers faced while teaching Costume History were mostly that ‘the pictorials in the text is not fully explainable’, the next were ‘most of the supplementary teaching materials or implements are not owned’, ‘have to explain very much in a short time’, and ‘the lectural explanation is insufficient’. 9. The solution for the difficulties that the highschool teachers faced while teaching Costume History was mostly ‘the information, on which audio-visual materials and implements are distributed in the market, should be easy to obtain’, the next opinions were ‘the school should provide enough experiment and practice expenses to buy audio-visual materials and implements’, and ‘education facilities of the Home Economics Department should be the main aspects in improving the teaching methods and should give special lectures about it’.

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Control of electrical types in the P-doped ZnO thin film by Ar/$O_2$ gas flow ratio

  • Kim, Young-Yi;Han, Won-Suk;Kong, Bo-Hyun;Cho, Hyung-Koun;Kim, Jun-Ho;Lee, Ho-Seoung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.11-11
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    • 2008
  • ZnO has a very large exciton binding energy (60 meV) as well as thermal and chemical stability, which are expected to allow efficient excitonic emission, even at room temperature. ZnO based electronic devices have attracted increasing interest as the backplanes for applications in the next-generation displays, such as active-matrix liquid crystal displays (AMLCDs) and active-matrix organic light emitting diodes (AMOLEDs), and in solid state lighting systems as a substitution for GaN based light emitting diodes (LEDs). Most of these electronic devices employ the electrical behavior of n-type semiconducting active oxides due to the difficulty in obtaining a p-type film with long-term stability and high performance. p-type ZnO films can be produced by substituting group V elements (N, P, and As) for the O sites or group I elements (Li, Na, and K) for Zn sites. However, the achievement of p-type ZnO is a difficult task due to self-compensation induced from intrinsic donor defects, such as O vacancies (Vo) and Zn interstitials ($Zn_i$), or an unintentional extrinsic donor such as H. Phosphorus (P) doped ZnO thin films were grown on c-sapphire substrates by radio frequency magnetron sputtering with various Ar/ $O_2$ gas ratios. Control of the electrical types in the P-doped ZnO films was achieved by varying the gas ratio with out post-annealing. The P-doped ZnO films grown at a Ar/ $O_2$ ratio of 3/1 showed p-type conductivity with a hole concentration and hole mobility of $10^{-17}cm^{-3}$ and $2.5cm^2/V{\cdot}s$, respectively. X-ray diffraction showed that the ZnO (0002) peak shifted to lower angle due to the positioning of $p^{3-}$ ions with a smaller ionic radius in the $O^{2-}$ sites. This indicates that a p-type mechanism was due to the substitutional Po. The low-temperature photoluminescence of the p-type ZnO films showed p-type related neutral acceptor-bound exciton emission. The p-ZnO/n-Si heterojunction LEO showed typical rectification behavior, which confirmed the p-type characteristics of the ZnO films in the as-deposited status, despite the deep-level related electroluminescence emission.

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Design and Implementation of 5G mmWave LTE-TDD HD Video Streaming System for USRP RIO SDR (USRP RIO SDR을 이용한 5G 밀리미터파 LTE-TDD HD 비디오 스트리밍 시스템 설계 및 구현)

  • Gwag, Gyoung-Hun;Shin, Bong-Deug;Park, Dong-Wook;Eo, Yun-Seong;Oh, Hyuk-Jun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.5
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    • pp.445-453
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    • 2016
  • This paper presents the implementation and design of the 1T-1R wireless HD video streaming systems over 28 GHz mmWave frequency using 3GPP LTE-TDD standard on NI USRP RIO SDR platform. The baseband of the system uses USRP RIO that are stored in Xilinx Kintex-7 chip to implement LTE-TDD transceiver modem, the signal that are transceived from USRP RIO up or down converts to 28 GHz by using self-designed 28 GHz RF transceiver modules and it is finally communicated HD video data through self-designed $4{\times}8$ sub array antennas. It is that communication method between USRP RIO and Host PC use PCI express ${\times}4$ to minimize delay of data to transmit and receive. The implemented system show high error vector magnitude performance above 25.85 dBc and to transceive HD video in experiment environment anywhere.

Properties of TiN films prepared by using the DC sputtering and HIPIMS. (DC 스퍼터링과 HIPIMS로 제조한 TiN 박막의 특성 비교)

  • Byeon, In-Seop;Yang, Ji-Hun;Jeong, Jae-Hun;Kim, Seong-Hwan;Jeong, Jae-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.102-102
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    • 2016
  • 본 연구에서는 직류 전원(direct current; DC)을 이용한 스퍼터링과 고전력펄스 마그네트론 스퍼터링(high-power impulse magentron sputtering; HIPIMS)의 두 가지 방법과 빗각 증착을 적용하여 제조한 티타늄 질화물(TiN) 박막의 미세구조 변화가 물성에 미치는 영향을 확인하였다. TiN 박막은 99.5%의 Ti 타겟을 사용하고, Ar가스와 $N_2$ 분위기에서 스테인리스(SUS304)와 초경(cdmented carbide; WC-10wt.%Co) 기판위에 코팅하였다. 기판은 알코올과 아세톤으로 초음파 세척을 실시한 후 진공용기에 장착하고 기본 진공도인 ${\sim}2.0{\times}10^{-5}Torr$ 까지 진공배기를 실시하였다. 기판과 타겟 간의 거리는 DC 스퍼터링은 10 cm, HIPIMS 스퍼터링은 8.5 cm 이었다. 진공용기의 압력이 기본 진공도까지 배기되면 Ar 가스를 ${\sim}10^{-2}Torr$로 주입한 후 기판에 라디오 주파수(radio frequency; RF) 전원으로 약 -800 V의 전압을 인가하여 글로우 방전을 발생시키고 약 30 분간 청정을 실시하였다. 기판의 청정이 끝난 후 기본 진공도까지 배기한 후 Ar와 $N_2$ 가스를 ${\sim}10^{-3}Torr$로 주입하여 TiN 코팅을 실시하였다. 빗각의 크기는 $45^{\circ}$$-45^{\circ}$이며, TiN 박막의 총 두께는 약 $2.5{\sim}4.0{\mu}m$ 로 유지하였다. 공정조건에 따라 TiN 박막의 주상정은 형태와 기울어진 각도가 다른 것을 확인하였다. DC 스퍼터링으로 제조된 TiN 박막은 기판홀더에 약 -100 V 의 bias 전압을 인가하면 인가하지 않은 박막에 비해 치밀한 박막의 성장과 경도 값도 증가하는 사실을 확인하였다. 또한 빗각을 적용하고 bias 전압을 인가하지 않은 시편에서 박리현상이 일어났다. HIPIMS로 제조한 TiN 박막은 bias 전압을 인가한 박막과 인가하지 않은 박막의 주상정 형상과 경도 값에 큰 차이가 없었으며, 박막의 박리현상은 모든 시편에서 일어나지 않았다. DC 스퍼터링으로 제조한 TiN 박막은 bias 전압을 인가하지 않으면 색상이 노란색이 아닌 갈색으로 나타났으며, HIPIMS으로 제조한 박막은 bias 전압 인가 유무에 상관없이 노란색 색상을 나타냈다. 앞서 설명한 DC 스퍼터링과 HIPIMS의 공정조건에 따라 나타난 박막의 경도, 색상, 물성변화 차이는 DC 스퍼터링보다 높은 HIPIMS의 이온화율에서 기인한 것으로 생각된다. 본 연구결과를 이용하면 다양한 형태의 박막 구조 제어가 가능하고 이러한 미세구조 제어를 통해서 박막의 물성도 제어가 가능할 것으로 판단된다.

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Applications of Regularized Dequantizers for Compressed Images (압축된 영상에서 정규화 된 역양자화기의 응용)

  • Lee, Gun-Ho;Sung, Ju-Seung;Song, Moon-Ho
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.39 no.5
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    • pp.11-20
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    • 2002
  • Based on regularization principles, we propose a new dequantization scheme on DCT-based transform coding for reducing of blocking artifacts and minimizing the quantization error. The conventional image dequantization is simply to multiply the received quantized DCT coefficients by the quantization matrix. Therefore, for each DCT coefficients, we premise that the quantization noise is as large as half quantizer step size (in DCT domain). Our approach is based on basic constraint that quantization error is bounded to ${\pm}$(quantizer spacing/2) and at least there are not high frequency components corresponding to discontinuities across block boundaries of the images. Through regularization, our proposed dequantization scheme, sharply reduces blocking artifacts in decoded images. Our proposed algorithm guarantees that the dequantization process will map the quantized DCT coefficients will be evaluated against the standard JPEG, MPEG-1 and H.263 (with Annex J deblocking filter) decoding process. The experimental results will show visual improvements as well as numerical improvements in terms of the peak-signal-to-noise ratio (PSNR) and the blockiness measure (BM) to be defined.

Efficiency Analysis for RFID-based Curtain Wall of unit Type Construction (RFID 기술 적용에 따른 유닛타입 커튼월 공사의 효율성 분석)

  • Kang, Hyun-Koo;Ha, Young-Seo;Lim, Chul-Woo;Kim, Chang-Duk;Yu, Jung-Ho
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.3
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    • pp.206-213
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    • 2008
  • Due to the following reasons, the management of curtain wall parts and material is very Important. Firstly, curtain wall work is one of the main works in High-rise building construction for it takes about $10{\sim}15%$ of the total construction cost. Secondly, the whole process of curtain wall work including manu acture, delivery, storage, installation and maintenance is very complicated and sometimes more than 30 companies involve in the process. Thus there are many control points for curtain wall units. Thirdly, there are not enough space on site for material storage and this situation is more serious for sites in urban area. The purpose of this research is to validate an information systems using RFID technology that is developed to manage the curtain wall units following the process of curtain wall work. For the validation, the cycle times of curtain wall work before and a ter the system was used. The results show that using the systems shorten the cycle time of the curtain wall work. Thus it is concluded that the system can increase the efficiency of managing curtain wall work.

Design and Implementation of Mobile Medical Information System Based Radio Frequency IDentification (RFID 기반의 모바일 의료정보시스템의 설계 및 구현)

  • Kim, Chang-Soo;Kim, Hwa-Gon
    • Journal of radiological science and technology
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    • v.28 no.4
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    • pp.317-325
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    • 2005
  • The recent medical treatment guidelines and the development of information technology make hospitals reduce the expense in surrounding environment and it requires improving the quality of medical treatment of the hospital. That is, with the new guidelines and technology, hospital business escapes simple fee calculation and insurance claim center. Moreover, MIS(Medical Information System), PACS(Picture Archiving and Communications System), OCS(Order Communicating System), EMR(Electronic Medical Record), DSS(Decision Support System) are also developing. Medical Information System is evolved toward integration of medical IT and situation si changing with increasing high speed in the ICT convergence. These changes and development of ubiquitous environment require fundamental change of medical information system. Mobile medical information system refers to construct wireless system of hospital which has constructed in existing environment. Through RFID development in existing system, anyone can log on easily to Internet whenever and wherever. RFID is one of the technologies for Automatic Identification and Data Capture(AIDC). It is the core technology to implement Automatic processing system. This paper provides a comprehensive basic review of RFID model in Korea and suggests the evolution direction for further advanced RFID application services. In addition, designed and implemented DB server's agent program and Client program of Mobile application that recognized RFID tag and patient data in the ubiquitous environments. This system implemented medical information system that performed patient data based EMR, HIS, PACS DB environments, and so reduced delay time of requisition, medical treatment, lab.

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A Study on Decision-Making Processes of Organic Foods (무공해식품의 구매의사결정에 관한 연구)

  • NamKung, Sok
    • Journal of the Korean Society of Food Culture
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    • v.9 no.4
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    • pp.379-394
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    • 1994
  • The purpose of this study was to identify the correlation between the factors influencing on housewives' decision-making processes of organic foods and the relating variables, and the 5 stages of decision-making processes of the EBK model is utilized in this study. The sample was selected from 411 housewives living in Seoul from 1st of September through 20th of September, 1993. Frequency, Percentage, Mean, Factor analysis, One-way ANOVA, Duncan's multiple range test, t-Test, Correlation, Multiple regression analysis and Path analysis were measured. Major results are as follows: 1. Purchasing motivation of the organic foods were in order of the health care, nutritive value and taste care. 2. The major informations source for the knowledge of organic foods were in order of TV/radio, newspaper/magazine, recommendations informations and advice through a family/friends/acquaintances. 3. Evalution criteria in shopping of organic foods, the total degree of consideration over the purchasing factors of organic foods was fairly high level: consumers thought much of the sanitation/freshness, nutritive value and the food safety. In this regard opinion leaders was dominantly mass media. Consumers have a tendency to purchase organic foods in consideration of their children and husband. 4. Major place to purchase organic foods are super markets and department stores. And When shopping organic foods, housewives by all means confirm the check points in their own mind, which were expiry date, manufactured date and packing condition, but unexpectedly manufactured company was out of concern. 5. Housewives usually satisfy with decision after purchasing organic foods, while they were fairly unsatisfied with the price, quality, incomplete description for ingredients and manufactured date. 6. The variables influencing to the sincerity when selecting the most desired organic foods is how be cares about the natural freshness of the foods and the types of residents in order. Another interesting tendency is the richer they are very considerate to decide. It is to say the people who cares more about the natural freshness is the sincerer when making decision and also the class who lives in the apartment house enjoying high income do not easily accept the product quality.

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The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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