The problem of the high peak to average ratio (PAPR) in OFDM signals is investigated with a brief presentation of the various methods used to reduce the PAPR with special attention to the clipping method. An alternative approach of clipping is presented, where the clipping is performed right after the IFFT stage unlike the conventional clipping that is performed in the power amplifier stage, which causes undesirable out of signal band spectral growth. In the proposed method, there is clipping of samples not clipping of wave, therefore, the spectral distortion is avoided. Coding is required to correct the errors introduced by the clipping and the overall system is tested for two types of modulations, the QPSK as a constant amplitude modulation and 16QAM as a varying amplitude modulation.
Under aerobic and anaerobic conditions, two laboratory-scale reactors were operated. Each reactor
was packed with 8.5 kg of shredded synthetic solid waste (less than 5 cm) that was prepared according to an
average composition of domestic solid waste in the city of Kirkuk. Using an air compressor, aerobic
conditions were created in the aerobic reactor. This study shows that the aerobic reactor was more efficient in
COD and BOD5 removal which were 97.88% and 91.25% while in case of anaerobic reactor, they were
66.53%and 19.11%, respectively.
A colloidal indium oxide (In2O3) nanoparticles (NPs) were synthesized pulsed laser ablation (PLA) of indium plate placed on the bottom of the quartz vessel containing (3ml) of pure ethanol. The influence laser energy on the properties of the formed nano-particles were characterized by using atomic force microscopy (AFM), X-ray diffraction (XRD), Ultraviolet Visible (UV-Vis) technique, and electrical properties measurements. The XRD revealed the crystallization structure of In2O3 nanoparticles and all the films having preferential orientation along (222) plane and intensity increases with increasing laser energy, The UV–Visible spect
... Show MoreThe need for optical fibers has emerged for its ability to transmit information with less attenuation and over long distances. In this work, four optical fibers with core radii from 1 μm to 4.75 μm in steps of 1.25 μm and a numerical aperture of 0.17 were studied and their modes properties have been calculated at a wavelength of 633 nm by using RP Fiber Calculator (free version 2022). Also, the effect of increasing the core radius on these properties has been studied. Multimode fibers can be obtained when the radius of the fiber core is large compared to the operating wavelength of the fiber which is less than the cutoff wavelength of the mode. Otherwise, a single-mode fiber is obtained. It has been concluded that all the calculated p
... Show MoreBackground: Astrocytic tumors are the most common primary tumors of the central nervous system. Several grading systems are used to grade astrocytomas. The most widely used system is the World Health Organization (WHO) classification (1979, 1993, 2000, and 2007) that grades astrocytomas (I-IV) based on cytological atypia, mitotic activity, vascular proliferation, and necrosis: pilocytic astrocytoma (grade I), diffuse astrocytoma (grade II), anaplastic astrocytoma (grade III), and glioblastoma (grade IV).
Objectives: The aim of this study is to evaluate p53 over expression , Ki-67 expression in astrocytomas and Correlate these two markers with histologic grade of astrocytomas.
Methods: Formalin fixed, paraff
The tax legal system, with its rules relating to imposing and assessing the tax and how to collect it, is one of the issues that the taxpayer is keen to follow-up on and caring about, but the aforementioned system is contested by two conflicting interests, the taxpayer’s interest in the view of a money-cutter and a means of always depriving of his wealth to the tax-imposing authority that It seeks to ensure the regular and steady flow of financial resources to the public treasury, which necessitates the presence of a judicial body entrusted with the task of securing a balance between these two conflicting interests from issues that consider themselves strongly in the tax field. It is one of the oldest human rights and public freedoms,
... Show MoreIn Paracoccus denitrificans Pd1222 bacterium, Pden_3633 encoding gene has been nominated to encode for Isovaleryl CoA dehydrogenase (IVDH) [1], the enzyme which involve in leucine catabolism pathway. In this study, this putative IVDH was investigated. IVDH encoding gene from P. denitrificans Pd1222 in addition to desired features for cloning, expression and purification have been designed and synthesized. The synthetic coding sequence was expressed in Escherichia coli. The enzyme was purified as a Strep-Tagged protein with a total protein 220.5 mg. An apparent molecular weight of 42.9 kDa was determined on SDS gel. Amino acid alignment showed a very high similarity (91-96%) with corresponding IVDH from several other Paracoccus species. A
... Show MoreThis study was aimed to use plant tissue culture technique to induce callus formation of Aloe vera on MS. Medium supplied with 10 mg/l NAA and 5 mg/l BA that exhibit the best results even with subculturing. As the method of [1] 1g. dru weight of callus induced from A. vera crown and in vivo crown were extracted then injected in HPLC using the standards of Ascorbic acid (vit. C), Salysilic acid and Nicotenic acid (vit. B5) to compare with the plant extracts. Results showed high potential of increasing some secondary products using the crown callus culture of A. vera as compared with in vivo crown, Ascorbic acid was 1.829 ?g/l in in vivo crown and increased to 3.905 ?g/l crown callus culture . Salysilic acid raised from 3.54 ?g/l in in vivo c
... Show MoreGender has considered and become a new trend in women's studies, as it reflects the behaviors, roles and attitudes imposed by society on its members in accordance with their biological nature,with focusing on gender rather than on concentration on women, which is closely linked to the vision that concentrates on women's problems which are not primarily according to their biological differences But rather to a greater extent to social, cultural, historical and religious barriers and Obstacles.
Therefore, the qualitative division due to the concept of "gender" is not a rigid biological division, but is relied on the broad general context through which the social division of work is done. Thus, content in the pages of Facebook with high-
The increasing demand for energy has encouraged the development of renewable resources and environmentally benign fuel such as biodiesel. In this study, ethyl fatty esters (EFEs), a major component of biodiesel fuel, were synthesized from soybean oil using sodium ethoxide as a catalyst. By-products were glycerol and difatty acyl urea (DFAU), which has biological characteristics, as antibiotics and antifungal medications. Both EFEs and DFAU have been characterized using Fourier transform infrared (FTIR) spectroscopy, and 1H nuclear magnetic resonance (NMR) technique. The optimum conditions were studied as a function of reaction time, reactant molar ratios, catalyst percentage and the effect of organic solvents. The conversion ratio of soybea
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