• Title/Summary/Keyword: Combiner

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Combining Ability for Morphological and Biochemical Characters in Mulberry (Morns spp.) under Salinity Stress

  • Vijayan, Kunjupillai;Chakraborti, Shyama Prasad;Doss, Subramaniam Gandhi;Ghosh, Partha Deb;Ercisli, Sezai
    • International Journal of Industrial Entomology and Biomaterials
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    • v.16 no.2
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    • pp.67-74
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    • 2008
  • A line x tester analysis was carried out in mulberry (Morns spp.) under different salinity levels to determine the changes in the genetic interaction of various morpho-biochemical characters. Five mulberry genotypes, 3 females and 2 males, differing in salt tolerance were selected for the study. Clones of these parents along with clones of the F1 hybrids were planted in earthen pots and subjected to different levels of salinity (0.0%, 0.25%, 0.50%, 0.75% and 1.00% NaCl). Data on morphological and biochemical characters were subjected to line x tester analysis. The result revealed significant variation among the parents studied. The prominence of non-additive gene effect under control condition suggests the need for well chalked out breeding program to exploit the non-fixable variance of components for improvement of plant height, leaf size and leaf yield, chlorophyll and photosynthesis in mulberry. However, under salinity stress a shift from non-additive gene effect to additive gene effect for the above said character further suggests the need for a change in breeding strategy. The general combining ability (GCA) analysis has identified English black as the best combiner among the parents and the specific combining ability analysis (SCA) found crosses of English black X C776 and Rotndiloba x Mandalaya were good for Plant height and leaf size and English black X C776 and Rotundiloba x C776 were good for biochemical proline and chlorophyll. From the performance of parents and their crosses under different salinity levels and also under normal cultural conditions it is concluded that in mulberry different approaches are required to develop varieties for the irrigated and saline conditions.

Implementation of a 13.56 MHz 5kW RF Generator for ISM Band Applications (ISM 대역 응용분야에 사용되는 13.56 MHz 5kW RF 제너레이터 구현)

  • Yoon, Young-Chul;Kim, Young
    • Journal of Advanced Navigation Technology
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    • v.20 no.6
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    • pp.556-561
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    • 2016
  • This paper describes implementation of a 13.56 MHz, 5 kW RF high power generator for ISM band applications. This RF generator consists of four LDMOS modules of 1.25kW class-AB push-pull power amplifier with drive amplifier and its outputs are combined by using Wilkinson type transmission-line transformers. Its generator has a high efficiency and output power better than linearity. In order to discharge power transistor heats, we used on water cooled copper plate. Also, these have a composite circuit of combiner and low-pass filter and safety circuit to detector over and reflected power. The RF generator has achieved a efficiency of 79 % at 5.33 kW of saturated power level experimentally.

Implementation of An Water-Cooled High Power Amplifier for Particle Accelerator (입자 가속기용 수냉식 고전력 증폭기 구현)

  • Yoon, Young-Chul;Kim, Young
    • Journal of Advanced Navigation Technology
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    • v.21 no.1
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    • pp.66-71
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    • 2017
  • This paper describes implementation of a 165 MHz, 5 kW RF high power amplifier (HPA) for particle accelerator applications. The HPA consists of a drive amplifier for main amplifiers driving, sixteen 600 W class-AB push-pull power amplifier pallets and Wilkinson power divider/combiner using lumped LC components, which are divided/combined power amplifier pallet outputs. To detected the amplifier circuit of normal and reflected output power conditions, we used a bidirectional coupler. To radiate heat of main power amplifier, we were used an water-cooled copper plates to go through a water for radiation of heat. The HPA of center frequency 165 MHz has archived an efficiency of 62.5 % at 5 kW of power level experimentally.

Performance Analysis of Multicarrier Code Select CDMA System for PAPR Reduction in Multipath Channels

  • Ryu, Kwan-Woong;Jin, Jiyu;Park, Yong-Wan;Choi, Jeong-Hee
    • Journal of Communications and Networks
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    • v.11 no.1
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    • pp.11-19
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    • 2009
  • Multicarrier direct sequence code division multiple access (MC DS-CDMA) is an attractive technique for achieving high data rate transmission. This is valid regardless of whether or not the potentially large peak-to-average power ratio (PAPR) is an important factor for its application. On the other hand, code select CDMA (CS-CDMA) is an attractive technique with constant amplitude transmission of multicode signal regardless of subchannels. This is achieved by introducing a code select method. In this paper, we propose a new multiple access scheme based on the combination of MC DS-CDMA and CS-CDMA. The proposed scheme, which we call MC CS-CDMA, includes as special cases the subclasses of MC DS-CDMA and CS-CDMA. This paper investigates the performance of these systems over a multipath frequency selective fading channel using a RAKE receiver with maximal ratio combiner. In addition, the PAPR of the proposed system is compared with that of both MC DS-CDMA and CS-CDMA. Simulation results demonstrate that the proposed system provides better PAPR reduction than MC DS-CDMA, at the expense of the complexity of the receiver and the number of available users. The numerical result demonstrates that the proposed system has better performance than MC DS-CDMA due to the increased processing gain and time diversity gain.

A Selective Wireless Power Transfer Architecture Using Reconfigurable Multiport Amplifier (재구성 다중포트 전력증폭기를 이용한 선택적 무선 전력 전송 구조)

  • Park, Seung Pyo;Choi, Seung Bum;Lee, Seung Min;Lee, Moon-Que
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.5
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    • pp.521-524
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    • 2015
  • This letter presents a selective wireless power transfer architecture using a reconfigurable multi-port amplifier. The proposed wireless power transfer architecture is composed of a phase shifter part controlled by FPGA, two class-E power amplifiers, a four-port power combiner and two coil loads. Depending on the phase control of FPGA, the power ratio of outputs at the two coil loads becomes 1:1, 2:0 and 0:2. The manufactured system has delivered 1W DC power to loads at 125 kHz. The total DC-to-DC conversion efficiency shows more than 40 % including PA efficiency of 79 %.

Implementation of Modular 3-Band RF for Disaster Voice Communication (재난음성통신을 위한 Modular 3-Band RF 개발)

  • Park, Jin-Hee;Lee, Soon-Hwa
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.6
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    • pp.23-28
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    • 2013
  • Because characteristics of diversity, large-scale and unpredictability of disaster are very difficult to make predict of disaster, rapid disaster response activity is important to reduce damage from disaster. Therefore emergency communication technology is essential to information sharing between field personnel in the field. Because the heterogeneous radios defined as some of 100MHz VHF, 400MHz UHF, and 800MHz emergency communication RF band are used in Korea, the field personnels need to have multiple radios. In order to use one radio per personnel, radio voice intercommunication is very necessary. We study on modular 3-Band RF to communicate between heterogeneous radios through single multi-band antenna and verify scalable of the number of equipped radios.

Pose and Expression Invariant Alignment based Multi-View 3D Face Recognition

  • Ratyal, Naeem;Taj, Imtiaz;Bajwa, Usama;Sajid, Muhammad
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.4903-4929
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    • 2018
  • In this study, a fully automatic pose and expression invariant 3D face alignment algorithm is proposed to handle frontal and profile face images which is based on a two pass course to fine alignment strategy. The first pass of the algorithm coarsely aligns the face images to an intrinsic coordinate system (ICS) through a single 3D rotation and the second pass aligns them at fine level using a minimum nose tip-scanner distance (MNSD) approach. For facial recognition, multi-view faces are synthesized to exploit real 3D information and test the efficacy of the proposed system. Due to optimal separating hyper plane (OSH), Support Vector Machine (SVM) is employed in multi-view face verification (FV) task. In addition, a multi stage unified classifier based face identification (FI) algorithm is employed which combines results from seven base classifiers, two parallel face recognition algorithms and an exponential rank combiner, all in a hierarchical manner. The performance figures of the proposed methodology are corroborated by extensive experiments performed on four benchmark datasets: GavabDB, Bosphorus, UMB-DB and FRGC v2.0. Results show mark improvement in alignment accuracy and recognition rates. Moreover, a computational complexity analysis has been carried out for the proposed algorithm which reveals its superiority in terms of computational efficiency as well.

Design of L-Band Cylindrical Active Phase Array Antenna Using Bent Dipoles (접힌 다이폴 구조를 적용한 L-Band 원통형 능동 위상배열 안테나 설계)

  • Lee, Man-Gyu;Kwon, Ickjin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.43-55
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    • 2013
  • In this paper, we propose a cylindrical active phased array antenna of Beam Steering Characteristics in the horizontal plane(H-plane) and vertical plane(E-Plane) on the cylinder form array structure. We design the bent dipole antenna of the cylindrical array structure adapted excellent mutual-coupling characteristics, designed and manufactured the cylindrical array antennas and power combiner/divider unit for power dividing and combining on the antenna. The radiating elements array spacing of Cylindrical array antenna were determined to avoid grating lobes at half power beam steering. Beam steering of the antenna was implemented with 6-bit phase shifter in the transceiver and have been designed based on the characteristics the antenna beam steering at -24 degrees to 24 degrees horizontal, vertical 0 degrees to 36 degrees beam steering. A cylindrical active phased array antenna that produced for verification the performance of the antenna are measured radiation characteristics in accordance with beam steering at L-Band.

Performance Improvement for Nonchoherent DS/CDMA Reverse Links using Channel Estimation and Multiuser Detection (비동기 복조 DS/CDMA 역방향 링크에서 채널 추정 및 다중 사용자 검파를 이용한 성능 개선)

  • 홍대기;윤석현;홍대식;강창언
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.5
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    • pp.755-764
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    • 2001
  • In this paper, we propose maximum likelihood (ML) decision feedback channel estimation (DFCE) for M-ary orthogonal modulation in direct sequence/code division multiple access (DS/CDMA) systems. The proposed DFCE uses the maximum combiner output in a RAKE receiver as decision feedback information, enabling M-ary orthogonal signals to be demodulated coherently and a RAKE receiver to use a em maximal ration combining (MRC) scheme. However, the performance of the proposed DFCE in the multiuser environment is severely degraded due to multiple access interference (MAI). To overcome this problem, a multistage parallel interference cancellation (PIC) scheme is combined with the proposed DFCE for multiuser environments. Accurate knowledge of the channel coefficient estimated by the proposed DFCE is used to regenerate the signal of each user for the multistage PIC scheme. According to the results of our simulations, the performance of coherent demodulation using the proposed system is significantly improved in comparison with conventional noncoherent demodulation.

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Combining Ability of Japonica Rices for Salinity Tolerance at Seedling Stage (자포니카 벼 품종의 유묘 내한성에 대한 조합능력)

  • Lee, Kyu-Seong;Park, Nam-Kyu;Yang, Sae-Jun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.3
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    • pp.270-274
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    • 1997
  • This experiment was conducted to evaluate the combining ability of japonica rices for improving the salinity tolerance at seedling stage. Nine varieties used in partial diallel analysis included three varieties of each tolerant, moderately tolerant and susceptible one. Twelve-day-old seedlings were grown in saline solution, initially at an EC of 6 dS /m for four days, followed by an EC of 12 dS /m for 20 days. The agronomic characters at seedling stage such as plant height, dry shoot weight and dry root weight were measured to analyze for combining ability of the parents. General combining ability(GCA) and specific combining ability(SCA) effects were highly significant for all tested parameters. However, mean squares for GCA were about five times larger than that for SCA suggesting the preponderance of additive gene action. Among tolerant varieties, Gaori and Namyang 7 were good combiner for improving the salinity tolerance at seedling stage in GCA as well as SCA.

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