• Title/Summary/Keyword: HPA

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Physico-chemical properties of late-incubation egg amniotic fluid and a potential in ovo feed supplement

  • Omede, A.A.;Bhuiyan, M.M.;lslam, A.F.;Iji, P.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.8
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    • pp.1124-1134
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    • 2017
  • Objective: This study explored the physico-chemical properties of late-incubation egg amniotic fluid and a potential in ovo feed (IOF) supplement. Methods: Amniotic fluid was collected from broiler breeders (Ross 308, 51 weeks and Cobb 500, 35 weeks) on day 17 after incubation. A mixture of high-quality soy protein supplement - Hamlet Protein AviStart (HPA) was serially diluted in MilliQ water to obtain solutions ranging from 150 to 9.375 mg/mL. The mixtures were heat-treated (0, 30, 60 minutes) in a waterbath ($80^{\circ}C$) and then centrifuged to obtain supernatants. The amniotic fluid and HPA supernatants were analysed for their physico-chemical properties. Results: Only viscosity and $K^+$ were significantly (p<0.05) different in both strains. Of all essential amino acids, leucine and lysine were in the highest concentration in both strains. The osmolality, viscosity and $pCO_2$ of the supernatants decreased (p<0.05) with decreasing HPA concentration. Heat treatment significantly (p<0.05) affected osmolality, pH, and $pCO_2$, of the supernatants. The interactions between HPA concentration and heat treatment were significant with regards to osmolality (p<0.01), pH (p<0.01), $pCO_2$ (p<0.05), glucose (p<0.05), lactate (p<0.01) and acid-base status (p<0.01) of HPA solutions. The $Ca^{2+}$, $K^+$, glucose, and lactate increased with increasing concentration of HPA solution. The protein content of HPA solutions decreased (p<0.05) with reduced HPA solution concentrations. The supernatant from 150 mg/mL HPA solution was richest in glutamic acid, aspartic acid, arginine and lysine. Amino acids concentrations were reduced (p<0.05) with each serial dilution but increased with longer heating. Conclusion: The values obtained in the primary solution (highest concentration) are close to the profiles of high-protein ingredients. This supplement, as a solution, hence, may be suitable for use as an IOF supplement and should be tested for this potential.

Robust Design for WCDMA Node B Amplifier by Taguchi Method and HALT (High Accelerated Life Test) (Taguchi Method 와 HALT(High Accelerated Life Test)를 이용한 WCDMA Node B Amplifier 강건설계)

  • Lee, Jun-Seo;Roh, Young-Seok;Hong, Jin-Pyo;Ahn, Kwang-Eun;Yon, Chul-Heum
    • 한국정보통신설비학회:학술대회논문집
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    • 2007.08a
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    • pp.407-410
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    • 2007
  • In the RRH (Radio Remote Head) of a WCDMA Node B System, an HPA (High Power Amplifier) is used in order to amplify the transmission RF signal. Upon designing an HPA, the design requirements demand that the intermodulation characteristics are optimized during design and that the stability of the characteristics is maintained in the field. In this DOE (Design of Experiments) research, a few vital factors that affect intermodulation characteristics were first selected; then, an optimal solution was produced for high reliability in a noisy environment in the field by employing the Taguchi Method, a statistical method used for a robust design. Furthermore, by employing HALT(High Accelerated Life Test) during the verification test, this experiment has verified that an HPA that was designed using the Taguchi Method proved to be a far more robust design than an HPA that was designed without using the method.

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THE IMPACT OF STRESS ON ADDICTION

  • Goeders Nick E.
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2004.11a
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    • pp.18-34
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    • 2004
  • This paper will review data obtained primarily from our preclinical investigations that show that exposure to stress has a significant impact on drug taking. Stress increases reward associated with psychomotor stimulants, possibly through a process similar to sensitization, and a growing clinical literature indicates that there is also a link between substance abuse and stress in human addicts. One explanation for the high concordance between stress-related disorders and drug addiction is the self-medication hypothesis, which suggests that a dually-diagnosed person often uses the abused substance to cope with tension associated with life stressors or to relieve symptoms of anxiety and depression resulting from a traumatic event. However, another characteristic of drug self-administration is that drug delivery and its subsequent effects on the HPA axis are under the direct control of the individual. This controlled activation of the HPA axis may result in the production of an internal state of arousal or stimulation that is actually sought by the individual (i.e., the sensation-seeking hypothesis). During abstinence, however, exposure to stressors or drug-associated cues can stimulate the HP A axis to remind the individual about the effects of the abused substance, thus producing craving and promoting relapse. Stress reduction, either alone or in combination with pharmacotherapies targeting the HPA axis may prove beneficial in reducing cravings and promoting abstinence in individuals seeking treatment for addiction. Of primary importance is to reduce the impact of cocaine-associated environmental stimuli on the HPA axis so that they no longer function as triggers for relapse.

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Improving Probability of Precipitation of Meso-scale NWP Using Precipitable Water and Artificial Neural Network (가강수량과 인공신경망을 이용한 중규모수치예보의 강수확률예측 개선기법)

  • Kang, Boo-Sik;Lee, Bong-Ki
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1027-1031
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    • 2008
  • 본 연구는 한반도 영역을 대상으로 2001년 7, 8월과 2002년 6월로 홍수기를 대상으로 RDAPS 모형, AWS, 상층기상관측(upper-air sounding)의 자료를 이용하였다. 또한 수치예보자료를 범주적 예측확률로 변환하고 인공신경망기법(ANN)을 이용하여 강수발생확률의 예측정확성을 향상시키는데 있다. 신경망의 예측인자로 사용된 대기변수는 500/ 750/ 1000hpa에서의 지위고도, 500-1000hpa에서의 층후(thickness), 500hpa에서의 X와 Y의 바람성분, 750hpa에서의 X와 Y의 바람성분, 표면풍속, 500/ 750hpa/ 표면에서의 온도, 평균해면기압, 3시간 누적 강수, AWS관측소에서 관측된 RDAPS모형 실행전의 6시간과 12시간동안의 누적강수, 가강수량, 상대습도이며, 예측변수로는 강수발생확률로 선택하였다. 강우는 다양한 대기변수들의 비선형 조합으로 발생되기 때문에 예측인자와 예측변수 사이의 복잡한 비선형성을 고려하는데 유용한 인공신경망을 사용하였다. 신경망의 구조는 전방향 다층퍼셉트론으로 구성하였으며 역전파알고리즘을 학습방법으로 사용하였다. 강수예측성과의 질을 평가하기 위해서 $2{\times}2$ 분할표를 이용하여 Hit rate, Threat score, Probability of detection, Kuipers Skill Score를 사용하였으며, 신경망 학습후의 강수발생확률은 학습전의 강수발생확률에 비하여 한반도영역에서 평균적으로 Kuipers Skill Score가 0.2231에서 0.4293로 92.39% 상승하였다.

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Design and Performance Analysis of Pre-Distorter Including HPA Memory Effect

  • An, Dong-Geon;Lee, Il-Jin;Ryu, Heung-Gyoon
    • Journal of electromagnetic engineering and science
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    • v.9 no.2
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    • pp.71-77
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    • 2009
  • OFDM(Orthogonal Frequency Division Multiplexing) signals sutler serious nonlinear distortion in the nonlinear HPA(High Power Amplifier) because of high PAPR(Peak Average Power Ratio). Nonlinear distortion can be improved by a pre-distorter, but this pre-distorter is insufficient when the PAPR is very high in an OPFDM system. In this paper, a DFT(Discrete Fourier Transform) transform technique is introduced for PAPR reduction. It is especially important to consider the memory effect of HPA for more precise predistortion. Therefore, in this paper, we consider two models, the TWTA(Traveling-Wave Tube Amplifier) model of Saleh without a memory effect and the HPA memory polynomial model that has a memory effect. We design a pre-distorter and an adaptive pre-distorter that uses the NLMS(Normalized Least Mean Square) algorithm for the compensation of this nonlinear distortion. Without the consideration of a memory effect, the system performance would be degraded, even if the pre-distorter is used for the compensation of the nonlinear distortion. From the simulation results, we can confirm that the proposed system shows an improvement in performance.

A Design of High Power Amplifier Predistortor using Carrier Complex Power Series Analysis (Carrier Complex Power Series 해석을 통한 대전력 증폭기용 전치 왜곡기 설계)

  • 윤상영;정용채
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.5
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    • pp.686-693
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    • 2001
  • In this paper, a new carrier complex power series which represents nonlinear transfer function of high power amplifier is derived. Using this transfer function, the nonlinear transfer function of predistortive circuit for linearizing the distortion effect of a HPA(High Power Amplifier) is derived and fabricated. A measured gain and $P_{1dB}$ of the fabricated HPA in IMT-2000 basestation transmitting band are 34.06 dB and 35.4 dBm. The predistortive circuit using inverse carrier complex power series is fabricated and operated with HPA. The predistortive HPA improves C/I(Carrier to Intermodulation) ratio of HPA by 17.01 dB(@Pout=25.43 dBm/tone) with 2-tone at 2.1375 GHz and 2.1425 GHz.

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A Study on the Output Signal Characteristics of Microwave Transistor (초고주파 트랜지스터의 출력 신호 특성에 관한 연구)

  • 박웅희;장익수;허준원
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.3
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    • pp.492-498
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    • 2000
  • When multi-carriers are applied to the high power amplifier(HPA) having nonlinear characteristics, the HPA output has unwanted IMD signals. The IMD signal is noise in the HPA. The magnitude and phase of the main and IMD signal of HPA output are changed as the input signal power is changed. If we know exactly the magnitude and phase characteristics of the main and IMD signal, we can design a more adequate linearizer and understand the characteristics of transistor. In this paper the magnitude and phase of the main and IMD signal of HPA output are measured and analyzed for variation of the input power.

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Propeller Performance Analysis for Human Powered Aircraft (인간동력 항공기용 프로펠러 성능해석)

  • Park, Poo-Min
    • Aerospace Engineering and Technology
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    • v.12 no.2
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    • pp.193-201
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    • 2013
  • Propeller is an important component of Human Powered Aircraft (HPA) propulsion system. HPA uses large diameter low rotational speed propeller to get high propeller efficiency. The propeller was designed by HPA propeller designing program. The propeller pitch is adjustable by rotating the blade axis angle at ground. Performance of the propeller for various parameters are analysed by the same program used for design. Off-design condition performance was also checked including pilot power change and flight speed change. The propeller was manufactured in ultra-light structure using carbon composite material down to 950g. The propeller was ground tested on ironbird and installed on KARI HPA. Finally the HPA flew 291m with this propeller.

A Study on the Effect of Spectrum Sharing/Overlapping in a Heterogeneous OFDM System with Nonlinear High Power Amplifiers (비선형 고전력 증폭기를 가진 이종 직교주파수분할다중화 시스템에서 스펙트럼 공유/중복 효과에 대한 연구)

  • Lee, Sung-bok;Park, Jaehyun;Park, Jae Cheol;Kang, Kyu-Min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.12
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    • pp.1707-1714
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    • 2016
  • This paper presents the effect of spectrum sharing/overlapping in a heterogeneous OFDM system with nonlinear High Power Amplifier (HPA). According to the spectrum sharing strategies, the achievable rate performances are analyzed. In the non-orthogonal spectrum sharing, we address how the portion of the overlapped or overlaid spectrum band and the nonlinear properties of HPA affect the system performance and accordingly, propose the optimized spectrum sharing strategies.

A Broadband and High Linearity HPA for TVWS (TVWS용 광대역 고선형 전력증폭기)

  • Kang, Sanggee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.10
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    • pp.613-615
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    • 2014
  • The design and implementation of a broadband and linear HPA(High Power Amplifier) for TVWS are presented in this paper. The spectrum mask and transmitted power of HPA for TVWS must be controlled and meet the regulations to minimize interference effects on present broadcasting systems. The implemented HPA has the operating frequency of 460 ~ 698MHz with $24.7{\pm}1dB$ gain, input reflection coefficient of below -25dB, output reflection coefficient of below -7.28dB and the linearity of -57.7dBc at 22.2dBm output power.