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Propagation Model Optimization Based on Ion Motion Optimization Algorithm for Efficient Deployment of eLTE Network

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Journal of Computer and Communications 2022年第11期10卷 171-196页

作者： Deussom Djomadji Eric Michel Tsague Njatsa Austene Beldine tonye emmanuel Department of Electrical and Electronic Engineering College of Technology University of Buea Buea Cameroon Division of Information and Communications Technology NASPT University of Yaoundé I Yaoundé Cameroon Department of Electrical and Telecommunications University of Yaoundé I Yaoundé Cameroon

Propagation models are the foundation for radio planning in mobile networks. They are widely used during feasibility studies and initial network deployment, or during network extensions, particularly in new cities. They can be used to calculate the power of the signal received by a mobile terminal, evaluate the coverage radius, and calculate the number of cells required to cover a given area. This paper takes into account the standard K factors model and then uses the Ion motion optimization (IMO) algorithm to set up a propagation model adapted to the physical environment of each of the Cameroonian cities of Yaoundé and Bertoua for different frequencies and technologies. Drive tests were made on the CDMA network in the city of Yaoundé on one hand and on an LTE TDD network in the city of Bertoua on the other hand. IMO is used as the optimization algorithm to deduct a propagation model which fits the environment of the two considered towns. The calculation of the root-mean-square error (RMSE) between the actual data from the drive tests and the prediction data from the implemented model allows the validation of the obtained results. A comparative study made between the RMSE value obtained by the new model and those obtained by the Okumura-Hata and K factors standard models, allowed us to conclude that the new model obtained in each of these two cities is better and more representative of our local environment than the Okumura-Hata currently implemented. The implementation shows that IMO can perform well and solve this kind of optimization problem;the newly obtained models can be used for radio planning in the cities of Yaounde and Bertoua in Cameroon.

关键词： Drive Test IMO Propagation Models Root Mean Square Error

Modeling of a DVB-S2 Transmission Chain with Optimization of Adjustment Parameters for a Good Quality of the Reception Signal

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International Journal of Communications, Network and System Sciences 2023年第1期16卷 1-20页

作者： Patrick Dany Bavoua Kenfack Alphonse Binele Abana emmanuel tonye Salim Adjiali Boukar Department of Electrical and Telecommunications Engineering National Advanced Polytechnic School University of Ya-ounde I Yaounde Cameroon

Digital television is part of our daily lives. We took an interest in the DVB-S2 standard in particular, because it is the one that governs the transmission by satellite of multimedia content from television programs. With ever-changing user needs, there are new challenges that the DVB-S2 standard is no longer able to meet due to errors caused by weather and hardware limitations. The main purpose of a satellite TV transmission is to obtain a video signal in reception of the best possible quality and at a high bit rate. It is therefore important to determine all the factors which could intervene in the process of transmission and which have a negative impact on the yield at the reception of the signal. We therefore designed and simulated the DVB-S and DVB-S2 transmission chains with QPSK modulation (and an FEC coding rate of 1/2), on MATLAB software (Simulink), and with an AWGN channel for the sake of comparison performance between these two chains. Then we carried out the design of the DVB-S2 transmission chain with an RF (Radio Frequency) satellite channel, by materializing all the elements which intervene in the downlink to evaluate the performance of this chain according to the factors which influence and/or degrade the signal quality between transmission and reception at the receiving earth station. The main results obtained relate to the DVB-S2 transmission chain and were interpreted using the visualization of the error rate blocks: With an AWGN channel, increasing the signal-to-noise ratio decreases the rate of erroneous packets and therefore improves the quality of the received signal. With an RF satellite channel on the downlink: increasing the transmit power improves the receive performance, this is useful for correcting most RF imperfections;having larger parabolic antennas is an advantage because they have greater gains;this makes it possible to minimize the rate of erroneous packets. These simulations allowed us to determine the precise and numerical imp

关键词： DVB-S2 Modulation AWGN RF Imperfection TV Transmission

Strengthening the Security of Supervised Networks by Automating Hardening Mechanisms

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Journal of Computer and Communications 2023年第5期11卷 108-136页

作者： Patrick Dany Bavoua Kenfack Alphonse Binele Abana emmanuel tonye Genevieve Elvira Ndjana Leka Department of Electrical and Telecommunications Engineering National Advanced School of Engineering of Yaounde University of Yaounde I Yaounde Cameroon

In recent years, the place occupied by the various manifestations of cyber-crime in companies has been considerable. Indeed, due to the rapid evolution of telecommunications technologies, companies, regardless of their size or sector of activity, are now the target of advanced persistent threats. The Work 2035 study also revealed that cyber crimes (such as critical infrastructure hacks) and massive data breaches are major sources of concern. Thus, it is important for organizations to guarantee a minimum level of security to avoid potential attacks that can cause paralysis of systems, loss of sensitive data, exposure to blackmail, damage to reputation or even a commercial harm. To do this, among other means, hardening is used, the main objective of which is to reduce the attack surface within a company. The execution of the hardening configurations as well as the verification of these are carried out on the servers and network equipment with the aim of reducing the number of openings present by keeping only those which are necessary for proper operation. However, nowadays, in many companies, these tasks are done manually. As a result, the execution and verification of hardening configurations are very often subject to potential errors but also highly consuming human and financial resources. The problem is that it is essential for operators to maintain an optimal level of security while minimizing costs, hence the interest in automating hardening processes and verifying the hardening of servers and network equipment. It is in this logic that we propose within the framework of this work the reinforcement of the security of the information systems (IS) by the automation of the mechanisms of hardening. In our work, we have, on the one hand, set up a hardening procedure in accordance with international security standards for servers, routers and switches and, on the other hand, designed and produced a functional application which makes it possible to: 1) Realise the confi

关键词： Hardening Supervised Network Cyber Security Information System

Okumura Hata Propagation Model Optimization in 400 MHz Band Based on Differential Evolution Algorithm: Application to the City of Bertoua

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Journal of Computer and Communications 2023年第5期11卷 52-69页

作者： Eric Michel Deussom Djomadji Ivan Basile Kabiena Joel Thibaut Mandengue Felix Watching emmanuel tonye Department of Electrical and Electronic Engineering College of Technology University of Buea Buea Cameroon Division of ICT National Advanced School of Post Telecommunication and ICT University of Yaounde I Yaounde Cameroon Department of Computer Engineering and Telecommunications National Advanced School of Engineering University of Douala Douala Cameroon Department of Electrical and Telecommunications Engineering National Advanced School of Engineering of Yaounde University of Yaounde I Yaounde Cameroon

Propagation models are the foundation for radio planning in mobile networks. They are widely used during feasibility studies and initial network deployment, or during network extensions, particularly in new cities. They can be used to calculate the power of the signal received by a mobile terminal, evaluate the coverage radius, and calculate the number of cells required to cover a given area. This paper takes into account the standard k factors model and then uses the differential evolution algorithm to set up a propagation model adapted to the physical environment of the Cameroonian cities of Bertoua. Drive tests were made on the LTE TDD network in the city of Bertoua. Differential evolution algorithm is used as the optimization algorithm to deduct a propagation model which fits the environment of the considered town. The calculation of the root mean square error between the actual data from the drive tests and the prediction data from the implemented model allows the validation of the obtained results. A comparative study made between the RMSE value obtained by the new model and those obtained by the Okumura Hata and free space models, allowed us to conclude that the new model obtained is better and more representative of our local environment than the Okumura Hata currently used. The implementation shows that Differential evolution can perform well and solve this kind of optimization problem;the newly obtained models can be used for radio planning in the city of Bertoua in Cameroon.

关键词： Radio Measurements Root Mean Square Error Differential Evolution Algorithm

Optimization of Mobile Network Radio Coverage by Automating Radio Parameter Updates Using Parsing

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Journal of Computer and Communications 2023年第4期11卷 79-102页

作者： Patrick Dany Bavoua Kenfack Alphonse Binele Abana emmanuel tonye Nadège Laure Bemehemie William Tchofo Tchouleko Department of Electrical and Telecommunications Engineering National Advanced School of Engineering of Yaoundé University of Yaoundé I Yaoundé Cameroon

The present work aims is to propose a solution for automating updates (MAJ) of the radio parameters of the ATOLL database from the OSS NetAct using Parsing. Indeed, this solution will be operated by the RAN (Radio Access Network) service of mobile operators, which ensures the planning and optimization of network coverage. The overall objective of this study is to make synchronous physical data of the sites deployed in the field with the ATOLL database which contains all the data of the coverage of the mobile networks of the operators. We have made an application that automates, updates with the following functionalities: import of radio parameters with the parsing method we have defined, visualization of data and its export to the Template of the ATOLL database. The results of the tests and validations of our application developed for a 4G network have made it possible to have a solution that performs updates with a constraint on the size of data to be imported. Our solution is a reliable resource for updating the databases containing the radio parameters of the network at all mobile operators, subject to a limitation in terms of the volume of data to be imported.

关键词： Radio Parameters Parsing ATOLL Database OSS NetAct ETL

Contribution for Efficient Planning of Millimeter Wave Frequencies: Case of the 80 GHz E-Band for High-Speed Broadband Transmissions

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Journal of Computer and Communications 2023年第11期11卷 111-148页

作者： Patrick Dany Bavoua Kenfack Alphonse Binele Abana emmanuel tonye Paul-Salomon Ngohe-Ekam Jacques Nyemb Nga Department of Electrical and Telecommunications Engineering National Advanced School of Engineering of Yaounde University of Yaounde I Yaounde Cameroon

Due to the very high demand for Internet data capacity from mobile and fixed customers as well as the saturation of conventional frequency bands by numerous services, many countries have opened the E band, for broadcasting services. E-band involves the creation of a significant number of links in a given area. The present work addressed the problem that arises in the context of transmission is that of assigning the frequencies of this band to these multiple transmission links. The aim of this work is to study and plan the radio links of the 80 GHz frequency and to implement them in a tool in order to define an optimal distribution on the telecommunications network by guaranteeing maximum flow of data traffic while minimizing the interference. The contribution of this work is part of its unique subject: the planning of E-band frequencies for improving the quality of service of transmission in the network of telecommunications operators. Also, it intends to contribute to the resolution of unsatisfied situations of poor planning of E-band radio frequencies in telecommunications networks. With the aim of opening several opportunities for alternative high-speed data transport solutions, our work has helped prove that E-band transmission links are very efficient with capacities in the gigabyte range.

关键词： Radio Beams E-Band Frequency Planning Microwave

Characterization of the Modified Lifting Scheme Compression Method of EMG Signals

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通讯和计算机（中英文版） 2011年第11期8卷 1013-1021页

作者： Ele Pierre Ntsama Eloundou Pascal tonye emmanuel Electrical Engineering and Telecommunications Department National Advanced School of Engineering University of Yaounde 1 in Cameroon PO Box 8698 Douala Cameroon Physics Department Faculty of Sciences University of Ngaoundere in Cameroon PO Box 454 Ngaoundere Cameroon Electrical Engineering and Telecommunications Department National Advanced School of Engineering University of Yaounde 1 in Cameroon PO Box 8390 Yaounde Cameroon

Studies on the distribution and abundance of plankton in Awba stream and reservoir, University of Ibadan

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Open Journal of Ecology 2013年第4期3卷 273-278页

作者： emmanuel Teryila Tyokumbur tonye Okorie Department of Zoology University of Ibadan Ibadan Nigeria

Studies were carried out on the distribution and abundance of plankton in Awba stream and reservoir, University of Ibadan over a period of four months between November 2011 and February 2012. Studies were carried out at four selected stations comprising station 1 as the entry point of the stream into the University, which also served as the control, station 2 receiving sewage, station 3 downstream along the stream and at a point along Awba Reservoir serving as station 4. 1 ml aliquot of each plankton sample from the study stations were examined under a binocular microscope while identification of the plankton was carried out using standard textbooks. The results of the phytoplankton indicated the absence of Microcystis flos-aquae, Agmenellum and Oscillatoria limnetica in station 1 while members of the family bacillariophyceae appeared at all stations. All species of chlorophyceae family except Spirogyra were peculiarly absent at station 2. Other phytoplankton representatives at this point (station 2) included Microcystis, Anabaena, Oscillatoria and Melosira. Paramecium was the only zooplankton group that was absent in station 1 but the only species presented in station 2. This station also revealed the lowest diversity indices and very low or no Jaccards coefficient of similarity with the other stations. The overall differences observed in the abundance, species richness, Margalef and Shannon-Wiener indices of diversity of plankton in the study reveal self purification or recovery downstream from the effluent discharge.

关键词： Abundance Distribution Plankton Awba Stream Reservoir

Spring-Value in Kirchhoff-Love Plate: Displacement, Buckling, Pure-Shear, Vibration

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Open Journal of Civil Engineering 2021年第1期11卷 96-118页

作者： tonye Ngoji Johnarry Rivers State University Port-Harcourt Nigeria

The stiffness model of the finite element is applied to the Kirchhoff-love closed-form plate buckling;buckling is always in focus in plate assemblages. The useful Eigen-value solutions are unable to separate a square plate from a much weaker long one in the most commonly-used all-simply supported plate (SSSS), among others. Spring-values of the Kirchhoff-Love plate are sought;once found, displacement-factors can be determined. Comparative displacements allow an easier and better evaluation of buckling-factors, pure-shear, vibration and so are termed “buckling-displacement-factors”. In testing, many plates in mixed boundary conditions are evaluated for displacement assisted buckling-solutions, first. The displacement-factors made from fundamental Eigen-vectors, in a single-pass, are found to be within about one-percent of known elastic values. It is found that the Kirchhoff-Love plate spring and the finite-element spring, demonstrated, here, in the assemblage of beam-elements, are equivalent from the results. In either case,

关键词： Spring-Stiffness Rectangular Plates Deflections Buckling Pure-Shear Vibration Plate’s-Field-Sheet