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Seroepidemiology of PPR in goats in Basrah province
دراسة وبائية مصلية لل PPP في الماعز في محافظة البصرة

Author: R. K. Muhsen رحمن كاظم محسن
Journal: Al-Qadisiyah Journal of Veterinary Medicine Sciences مجلة القادسية لعلوم الطب البيطري ISSN: 18185746 23134429 Year: 2013 Volume: 12 Issue: 1 Pages: 139-143
Publisher: Al-Qadisiyah University جامعة القادسية

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Abstract

This study was conducted in Basrah at period from March throughout the September 2011. 1175 blood samples were collected from goats in five regions of Basrah province that have no signs of disease and no any history of vaccination to estimate the seroprevalence of PPR in goats and undergoes to the cELISA test. The results of the study revealed that , the seroprevalence of the disease was 27.6 % . There were no significant differences in the seroprevalence in relation to sex and regions of the study (P ˃ 0.05 ). On other hand, the prevalence of PPR was higher significantly in the goats between 1 – 3 years of age compared with other age groups.

أجريت هذه الدراسة في البصرة للفترة من اذار الى أيلول 2011 . تم جمع 1175 نموذج دم من الماعز غير الملقح سابقا في خمس مناطق جغرافية من محافظة البصرة و خضعت نماذج الدم لاختبار الاليزا للتحري عن الاضداد . أظهرت النتائج ان نسبة انتشار طاعون المجترات الصغيرة في الماعز كانت 27.6 % , ولم تسجل فروقات معنوية في نسبة انتشار المرض بين الاناث و الذكور وكذلك بين مناطق الدراسة المختلفة . كما أظهرت الدراسة ان نسبة انتشار المرض كانت أعلى معنويا في الماعز بعمر 1 – 3 سنوات مقارنة بالفئات العمرية الاخرى .


Article
NON-LINEARITY DISTORTION MITIGATION OF DOWNLINK-LTE SYSTEM USING MODIFIED AMPLITUDE CLIPPING AND FREQUENCY DOMAIN RANDOMIZATION

Authors: Montadar Abas Taher --- Abidaoun Hamdan Shallal --- Ilham Hameed Qaddoori
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2015 Volume: 8 Issue: 4 Pages: 613-617
Publisher: Diyala University جامعة ديالى

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Abstract

Wireless telecommunication systems are almost the most dominant field of the communication systems context nowadays especially the long-term evolution (LTE) system. Orthogonal frequency division multiplexing (OFDM), has become the base for current and future communication systems, because of its capability to combat multipath and fading channels and its competency for high data rate transmissions. However, coherent combination of subcarriers leads to large power peaks with respect to the average power level; this is the so-called peak power ratio (PPR). Various methodologies are available in the literature, the simple approach is the amplitude clipping. However, amplitude clipping causes in-band distortion and out-of-band-radiation, thus, the bit error rate (BER) performance will degrades dramatically. Taher et al (2014) suggested a new amplitude-clipping algorithm, where the core-clipping function was replaced with a non-distorting function, but the proficiency of reducing the PPR was not in the good extent. In this paper, the new clipping function will be supported by frequency-domain randomization operation, such that the coherent combination of the OFDM subcarriers will not stay in the same order, leading to lower PPR at the output of the power amplifier. Results show that the hybrid combination of the randomization process with the new clipping function produces lower values of PPRs. Thus, the proposed approach has gotten 1.5 dB more reduction magnitude in the PPR with respect to Taher et al scheme. The complementary cumulative distribution function (CCDF) was the tool to monitor the PPR performance behavior.

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