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A Comprehensive Survey of Candidate Waveforms for 5G, beyond 5G and 6G Wireless Communication Systems

Open Journal of Applied Sciences 2023年第1期13卷 136-161页

作者： Bakhit amine Adoum Kalsouabe Zoukalne Mahamat Saleh idriss Ali Mahmoud Ali Amir Moungache Mahamoud Youssouf Khayal Ecole Nationale Superieure des Technologies de l’Information et de la Communication (ENASTIC) N’Djamena Tchad Institute of Sciences and Techniques of Abeche (INSTA) Abeche Tchad Université de N’Djamena N’Djamena Tchad Virtual University of Chad N’djamena Tchad Centre National de Recherche pour le Developpement (CNRD) N’djamena Tchad

The evolution of global mobile data over the past decades in broadcasting, Internet of Things (IoT), education, healthcare, commerce, and energy has put strong pressure on 3G/4G mobile networks to improve their service offerings. These generations of mobile networks were initially invented to meet the requirements of the above-mentioned applications. However, as the requirements in these applications continue to increase, new mobile technologies such as 5G (fifth generation), 5G and beyond (B5G, beyond fifth generation), and 6G (sixth generation) are still progressing and being experimented. These networks are very heterogeneous generations of mobile networks that will have to offer very high throughput per user, good energy efficiency, better traffic capacity per area, improved spectral efficiency, very low latency, and high mobility. To meet these requirements, the radio interface of future mobile networks will have to be flexible and rationalized the available frequency resources. Therefore, new modulation methods, access techniques and waveforms capable of supporting these technological changes are proposed. This review presents brief descriptions of the types of 5G, B5G, and 6G waveforms. The 5G consists of OFDM including its transmission techniques: generalized frequency division multiplexing (GFDM), filter bank based multi-carrier (FBMC), universal filtered multi-carrier (UFMC), and index modulation (IM). Meanwhile, the 6G covers orthogonal time frequency space (OTFS), orthogonal chirp division multiplexing (OCDM) and orthogonal time sequence multiplexing (OTSM). The networks’ potentialities, advantages, disadvantages, and future directions are outlined.

关键词： Modulation 5G B5G 6G Waveforms

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Robust Estimators for Poisson Regression

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Open Journal of Statistics 2023年第1期13卷 112-118页

作者： idriss Abdelmajid idriss Weihu Cheng College of Applied Science Department of Statistics Beijing University of Technology Beijing China

The present paper proposes a new robust estimator for Poisson regression models. We used the weighted maximum likelihood estimators which are regarded as Mallows-type estimators. We perform a Monte Carlo simulation study to assess the performance of a suggested estimator compared to the maximum likelihood estimator and some robust methods. The result shows that, in general, all robust methods in this paper perform better than the classical maximum likelihood estimators when the model contains outliers. The proposed estimators showed the best performance compared to other robust estimators.

关键词： Poisson Regression Model Maximum Likelihood Estimator Robust Estimation Contaminated Model Weighted Maximum Likelihood Estimator

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MiR-140 downregulates fatty acid synthesis by targeting transforming growth factor alpha(TGFA)in bovine mammary epithelial cells

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Journal of Integrative Agriculture 2022年第10期21卷 3004-3016页

作者： CHU Shuang-feng ZHAO Tian-qi Abdelaziz Adam idriss ARBAB YANG Yi CHEN Zhi YANG Zhang-ping College of Animal Science and Technology Yangzhou UniversityYangzhou 225009P.R.China Joint International Research Laboratory of Agriculture&Agri-Product Safety Yangzhou UniversityYangzhou 225009P.R.China Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses College of Veterinary MedicineYangzhou UniversityYangzhou 225009P.R.China

Fat is an indispensable nutrient and basic metabolite for sustaining life,and milk is particularly rich in fatty acids,including a variety of saturated and unsaturated fatty ***(miRNA)and mRNA play an important role in the regulation of milk fat metabolism in mammary gland *** has been shown that lipid metabolism has a complex transcriptional regulation,but the mechanism by which milk fat synthesis is regulated through miRNA–mRNA interactions is poorly *** this study,we performed transcriptome sequencing with bovine mammary gland tissue in the late lactation(270 and 315 days after parturition)to identify the key gene that regulating milk fat metabolism.A total of 1207 differentially coexpressed genes were selected,828 upregulated genes and 379 downregulated genes were *** transforming growth factor alpha(TGFA)gene was selected as the target gene,and luciferase reporter assay,Western blotting and q RT-PCR were used for further *** results demonstrated that miR-140 was an upstream regulator of TGFA,and miR-140 could inhibit(P<0.01)unsaturated fatty acid and triglyceride(TAGs)production in bovine mammary epithelial cells(BMECs).In contrast,TGFA promoted(P<0.01)unsaturated fatty acid and TAG *** experiments further indicated the mi R-140/TGFA regulatory *** together,these results suggest that the mi R-140/TGFA pathway can inhibit(P<0.01)milk fat metabolism and improve milk quality by genetic means.

关键词： bovine mammary epithelial cells TGFA transcriptome sequencing miR-140 fatty acid metabolism

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Weighted Maximum Likelihood Technique for Logistic Regression

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Open Journal of Statistics 2023年第6期13卷 803-821页

作者： idriss Abdelmajid idriss Weihu Cheng Yemane Hailu Fissuh Department of Statistics Faculty of Science Beijing University of Technology Beijing China Department of Statistics Aksum University Tigray Ethiopia

In this paper, a weighted maximum likelihood technique (WMLT) for the logistic regression model is presented. This method depended on a weight function that is continuously adaptable using Mahalanobis distances for predictor variables. Under the model, the asymptotic consistency of the suggested estimator is demonstrated and properties of finite-sample are also investigated via simulation. In simulation studies and real data sets, it is observed that the newly proposed technique demonstrated the greatest performance among all estimators compared.

关键词： Logistic Regression Clean Model Robust Estimation Contaminated Model Weighted Maximum Likelihood Technique

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The Performance of Robust Methods in Logistic Regression Model

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Open Journal of Statistics 2020年第1期10卷 127-138页

作者： idriss Abdelmajid idriss Ahmed Weihu Cheng College of Applied Science Department of Statistics Beijing University of Technology Beijing China

Logistic regression is the most important tool for data analysis in various fields. The classical approach for estimating parameters is the maximum likelihood estimation, a disadvantage of this method is high sensitivity to outlying observations. Robust estimators for logistic regression are alternative techniques due to their robustness. This paper presents a new class of robust techniques for logistic regression. They are weighted maximum likelihood estimators which are considered as Mallows-type estimator. Moreover, we compare the performance of these techniques with classical maximum likelihood and some existing robust estimators. The results are illustrated depending on a simulation study and real datasets.?The new estimators showed the best performance relative to other estimators.

关键词： Logistic Regression Maximum Likelihood Estimator Robust Estimation Outlier Weighted Maximum Likelihood

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Dietary betaine activates hepatic VTGⅡexpression in laying hens associated with hypomethylation of GR gene promoter and enhanced GR expression

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Journal of Animal Science and Biotechnology 2018年第2期9卷 381-390页

作者： Nagmeldin A.Omer Yun Hu Yan Hu Abdulrahman A.idriss Halima Abobaker Zhen Hou Haibo Dong Ruqian Zhao MOE Joint International Research Laboratory of Animal Health&Food Safety Nanjing Agricultural UniversityNanjing 210095People’s Republic of China Key Laboratory of Animal Physiology&Biochemistry Nanjing Agricultural UniversityNanjing 210095People’s Republic of China Jiangsu Collaborative Innovation Centre of Meat Production and Processing Quality and Safety ControlNanjing 210095People’s Republic of China Poultry Institute Chinese Academy of Agriculture SciencesYangzhouJiangsuChina

Background: Vitellogenin(VTG) is a precursor of egg yolk proteins synthesized within the liver of oviparous vertebrates. Betaine is an important methyl donor that is reported to improve egg production of laying hens with an unclear mechanism. In the present study, we fed betaine-supplemented diet(0.5%) to laying hens for 4 wk and investigated its effect on VTGII expression in the ***: Betaine did not affect chicken weight, but significantly(P < 0.05) increased egg laying rate accompanied with a significant(P < 0.05) increase in hepatic concentration and plasma level of VTGI. Plasma estrogen level did not change,but the hepatic expression of estrogen receptor α(ERα) mR NA was significantly(P < 0.05) up-regulated. Betaine did not affect the protein content of ERα, but significantly(P < 0.05) increased hepatic expression of glucocorticoid receptor(GR)at both mR NA and protein levels. Also, ERα/GR interaction tended to be enhanced in the liver nuclear lysates of betainesupplemented hens as determined by co-immunoprecipitation. Furthermore, dietary betaine supplementation significantly increased(P < 0.05) the hepatic expression of methyl-transfer enzymes, such as BHMT, GNMT, and DNMT1,which was associated with higher SAM/SAH ratio and hypomethylation of GR promoter ***: Betaine activates hepatic VTGII expression in association with modified DNA methylation of GR gene promoter, GR expression and ERα/GR interaction. Activation of hepatic VTGII expression may contribute, at least partly, to improved egg production in betaine-supplemented hens.

关键词： Betaine Glucocorticoid receptor Hypomethylation Laying hens Vitellogenin

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Pathological,immunohistochemical and microbiologicalal analysis of lacrimal sac biopsies in patients with chronic dacrocystitis

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International Journal of Ophthalmology(English edition) 2013年第6期6卷 817-826页

作者： Rowayda Mahmoud Amin Faten Aly Hussein Hisham Farouk idriss Nesrine Fathy Hanafy Dina Mohamed Abdallah Department of Ophthalmology Alexandria Faculty of Medicine Department of Microbiology Alexandria Faculty of Medicine Department of Pathology Alexandria Faculty of Medicine

AIM:To analyze cases of obstruction of the nasolacrimal duct which creates a fertile environment for secondary bacterial Infection and can result in dacryocystitis,which is a constant threat to cornea and orbital soft tissue and a potential source of endophthalmitis following intraocular *** majority of obstructions of the lacrimal excretory outflow system are acquired ones occurring in adulthood and involving the distal parts of the *** obstruction may be primary/idiopathic or secondary to a wide variety of infectious,inflammatory,traumatic,mechanical,toxic or neoplastic causes mimicking idiopathic *** cases are treated by dacryocystorhinostomy(DCR).METHODS:The present study was conducted to determine the histopathologic,immunohistochemical and current microbiologic characteristics of lacrimal sac specimens in patients undergoing external ***:Non-specific lacrimal sac pathology was present in all 33 cases and 81.8%of the cases showed moderate chronic inflammation with a chronic inflammatory score(CIS)ranging between 4 and 6,whereas 12.12%showed severe inflammatory changes with a CIS of *** degree of inflammation was seen in6.06%with a CIS of *** total prevalence of grampositive,gram-negative,and culture-negative samples were 59.4%,37.5%,and 3%***:Non-specific chronic inflammation withfibrosis is indeed the most commonly reported histopathological finding in lacrimal sac wall biopsy specimens.

关键词： dacrocystitis lacrimal sac biopsy chronic inflammation lacrimal duct obstruction

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Effective Mass Model Reduced to Ordinary Mass Using Newton’s, Quantum and Generalized Special Relativity

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Natural Science 2021年第9期13卷 398-406页

作者： Nagwa idriss Ali Ahmed Mohamed idriss Ahmed Mubarak Dirar Abd-Alla Department of Physics Faculty of Science and Art (Dariah) Qassim University Almulid KSA Department of Physics and Mathematics Hantoub Faculty of Education Gezira University Hantoub Sudan Department of Physics Faculty of Science Sudan University of Science and Technology Khartoum Sudan

The concept of the effective mass in crystals shows that the electron mass is affected by the crystal field and was experimentally verified. A useful expression for effective mass was obtained. Unfortunately this expression showed that the effective mass vanishes in the ab-sence of the external field. This is in conflict with observations which show that it reduces to the ordinary mass. To cure this defect a new model is developed assuming the existence of vacuum force as verified experimentally as shown by Casimir effect. Using Newton’s second law and the quantum expression of momentum, useful expressions were found. The same expression was found using generalized special relativity. Strikingly the three models reduced to the conventional one in the absence of vacuum, they also reduced to the ordinary electron mass in the absence of all forces.

关键词： Effective Mass Newton’s Second Quantum Momentum Generalized Special Relativity

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A Simulation Study on Comparing General Class of Semiparametric Transformation Models for Survival Outcome with Time-Varying Coefficients and Covariates

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Open Journal of Statistics 2019年第2期9卷 169-180页

作者： Yemane Hailu Fissuh Tsegay Giday Woldu idriss Abdelmajid idriss Ahmed Abebe Zewdie Kebebe Department of Statistics College of Applied Sciences Beijing University of Technology Beijing China Department of Statistics College of Natural and Computational Sciences Aksum University Aksum Ethiopia Department of Mathematics College of Applied Sciences Beijing University of Technology Beijing China School of Software Engineering Faculty of Information Technology Beijing University of Technology Beijing China

The consideration of the time-varying covariate and time-varying coefficient effect in survival models are plausible and robust techniques. Such kind of analysis can be carried out with a general class of semiparametric transformation models. The aim of this article is to develop modified estimating equations under semiparametric transformation models of survival time with time-varying coefficient effect and time-varying continuous covariates. For this, it is important to organize the data in a counting process style and transform the time with standard transformation classes which shall be applied in this article. In the situation when the effect of coefficient and covariates change over time, the widely used maximum likelihood estimation method becomes more complex and burdensome in estimating consistent estimates. To overcome this problem, alternatively, the modified estimating equations were applied to estimate the unknown parameters and unspecified monotone transformation functions. The estimating equations were modified to incorporate the time-varying effect in both coefficient and covariates. The performance of the proposed methods is tested through a simulation study. To sum up the study, the effect of possibly time-varying covariates and time-varying coefficients was evaluated in some special cases of semiparametric transformation models. Finally, the results have shown that the role of the time-varying covariate in the semiparametric transformation models was plausible and credible.

关键词： Estimating Equation Semiparametric Transformation Models Time-to-Event Outcomes Time-Varying Coefficients Time-Varying Covariate

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Efficient Information Set Decoding Based on Genetic Algorithms

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International Journal of Communications, Network and System Sciences 2012年第7期5卷 423-429页

作者： Ahmed Azouaoui idriss Chana Mostafa Belkasmi SIME Lab. ENSIAS Mohammed V-Souissi University Rabat Morocco

In this paper, we describe a hard-decision decoding technique based on Genetic Algorithms (HDGA), which is applicable to the general case of error correcting codes where the only known structure is given by the generating matrix G. Then we present a new soft-decision decoding based on HDGA and the Chase algorithm (SDGA). The performance of some binary and non-binary Linear Block Codes are given for HDGA and SDGA over Gaussian and Rayleigh channels. The performances show that the HDGA decoder has the same performances as the Berlekamp-Massey Algorithm (BMA) in various transmission channels. On the other hand, the performances of SDGA are equivalent to soft-decision decoding using Chase algorithm and BMA (Chase-BMA). The complexity of decoders proposed is also discussed and compared to those of other decoders.

关键词： Genetic Algorithms (GA) Error Correcting Codes RS Codes Information Set Decoding Chase Algorithm

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