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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Providing value-added services to cellphone contract clients - a hybrid recommendation approach

Ndlovu, Mpumelelo January 2016 (has links)
A thesis submitted in fulfilment of the requirements for the degree of Master of Science Computer Science in the School of Computer Science. Faculty of Science November 21, 2016. / There is stiff competition for customers and market share in the South African telecommunications industry amongst the four predominant mobile service providers, namely Vodacom, MTN, Cell C and Telkom Mobile. The First National Bank (FNB) through one of its entities, FNB Connect, has also joined this intensely competitive environment. These companies face a constant challenge of having to come up with new and innovative ways of attracting new customers and retaining their current ones. Cell C has embarked on a good strategy of claiming solid market share and growing itself against the competition by using the Private Label Promotions (PLP) group, a leading BEE Level 3 company that provides a variety of business solutions, to market GetMore, its value-added service package. A recommender system could be used to suggest and promote the items available in this package to existing and potential clients (users). There are different approaches to recommendation, the most widely used ones being the collaborative and content-based recommendation. The collaborative filtering approach uses the ratings of other users to recommend the items the current (active) user might like. In the content-based approach, items are recommended in terms of their content similarity to items a user has previously liked, or elements that have matched a user’s attributes (features). Hybrid recommendation approaches are used To eliminate the drawbacks individually associated with the CF and CBF approaches and to leverage their advantages. One of the aims of this research was to design and implement a prototype hybrid recommender system that would be used to recommend Cell C’s GetMore package to current and potential subscribers. The system was to implement matrix factorisation (collaborative) and cosine similarity (content-based) techniques. Several experiments were conducted to evaluate its performance and quality. The metrics used included Mean Absolute Error (MAE), Root Mean Squared Error (RMSE) and Area Under the ROC Curve (AUC). We expected the proposed hybrid recommender system would leverage the advantages provided by its different components and demonstrate its effectiveness in providing Cell C’s customers with accurate and meaningful recommendations of its GetMore package services. Keywords: Content-based Recommendation, Collaborative Recommendation, Hybrid Recommendation, Cosine Similarity, Matrix Factorisation, Association Rule Mining, J48 Classifier, Decision Table, Naive Bayes, Simple K-means, Expectation Maximization, Farthest First, Predictive Apriori / LG2017
52

Spreading factor optimization and random access stability control for IMT-2000.

January 2000 (has links)
Ho Chi-Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 63-[64]). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- The 2.5G Systems --- p.3 / Chapter 1.2.1 --- HSCSD --- p.3 / Chapter 1.2.2 --- GPRS --- p.3 / Chapter 1.2.3 --- EDGE --- p.4 / Chapter 1.2.4 --- IS-136 --- p.4 / Chapter 1.3 --- The Evolution from 2G/2.5G to 3G --- p.4 / Chapter 1.3.1 --- GSM Data Evolution --- p.4 / Chapter 1.3.2 --- TDMA Data Evolution --- p.5 / Chapter 1.3.3 --- CDMA Data Evolution --- p.6 / Chapter 1.4 --- UTRA --- p.7 / Chapter 1.4.1 --- UTRA FDD --- p.8 / Chapter 1.4.2 --- UTRA TDD --- p.18 / Chapter 1.4.3 --- Transport Channels --- p.25 / Chapter 2 --- Spreading Factor Optimization for FDD Downlink --- p.27 / Chapter 2.1 --- The Optimal Channel Splitting Problem --- p.28 / Chapter 2.2 --- Spreading Factor Optimization for FDD Downlink Dedicated Chan- nel --- p.30 / Chapter 3 --- Random Access Channel Stability Control --- p.33 / Chapter 3.1 --- Random Access Slotted Aloha --- p.33 / Chapter 3.1.1 --- System model --- p.33 / Chapter 3.1.2 --- Probability of Code-Collision --- p.34 / Chapter 3.1.3 --- Throughput Analysis of Random Access in TD/CDMA System --- p.37 / Chapter 3.1.4 --- Retransmission --- p.42 / Chapter 3.1.5 --- System Delay --- p.42 / Chapter 3.2 --- Random Access Channel Stability Control --- p.43 / Chapter 3.2.1 --- System Model --- p.43 / Chapter 3.2.2 --- Random Access Procedure --- p.44 / Chapter 3.3 --- Random Access Channel Stability Control Alogrithm --- p.47 / Chapter 3.3.1 --- Simulation --- p.49 / Chapter 3.4 --- Multi-class Model --- p.55 / Chapter 4 --- Conclusions and Topics for Future Study --- p.60 / Chapter 4.1 --- Thesis Conclusions --- p.60 / Chapter 4.2 --- Future Work --- p.61 / Chapter 4.2.1 --- Downlink and Uplink resource allocation in TDD --- p.61 / Chapter 4.2.2 --- Resource Unit Packing in TDD --- p.62 / Chapter 4.2.3 --- Other Topics --- p.62 / Bibliography --- p.63
53

The impact of cellular phone language on academic writing at high schools : a case of Mankweng Circuit

Matlakala, Kwetepe John January 2014 (has links)
Thesis (M.A. (Translation Studies and Linguistics)) -- University of Limpopo, 2014 / Refer document
54

A fuzzy logic approach for call admission control in cellular networks.

Tokpo Ovengalt, Christophe Boris. January 2014 (has links)
M. Tech. Electrical Engineering. / Discusses Call Admission Control (CAC) is a standard operating procedure responsible for accepting or rejecting calls based on the availability of network resources. It is also used to guarantee good Quality of Service (QoS) to ongoing users. However, there are a number of imprecisions to consider during the admission and handoff processes. These uncertainties arise from the mobility of subscribers and the time-varying nature of key admission factors such as latency and packet loss.These parameters are often imprecisely measured, which has a negative impact on the estimation of a channel spectral efficiency. In mobile networking, greater emphasis is towards delivering good QoS to real-time (RT) applications. It has become increasingly necessary to develop a model capable of handling uncertainties associated with the network in order to improve the quality of decisions relating to CAC. Type-1 and Type-2 Fuzzy Logic Controllers (FLCs) were deployed to allow the CAC to make better decisions in the presence of numerous uncertainties. The model successfully proposed associated meanings and degrees of certainty to the measured values of loss and latency by means of fuzzy sets and Membership Functions (MFs). The results obtained show that the fuzzy-based CAC performs better by reducing the call blocking and call dropping probabilities which are some of the key measurement parameters of QoS in wireless networking.
55

Approaches for traffic classification and the optimisation of radio resources in cellular networks : application to South Africa

Kurien, Anish Mathew. January 2012 (has links)
D. Tech. Electrical Engineering. / Objectives of the study is to propose a suitable feature extraction and classication approach that is capable of adapting to the non-linear nature and the noise contained in the time series data. The end goal of subscriber classication in this study is to utilise the subscriber information extracted for a new radio resource optimisation model that focuses on the Channel Allocation Problem CAP. Although there they have been various models proposed in literature for solving of the CAP problem, the utilisation of subscriber related information in the CAP has not been directly considered.
56

A model of mobile phone voting system for South Africa.

Mpekoa, Noluntu. January 2013 (has links)
M. Tech. Information Technology / Voting is a widely spread and democratic way of making decisions. For centuries, South Africa has been using the popular paper-based voting system though it does not provide the desirable blend of accessibility and efficiency. Missing ballot papers, invalid votes and miscount are some of the challenges that come with the paper-based voting system. Time is precious to everyone and correct information is even more precious in the fast-paced information technology era. Merging all these together we look in for easier, effective, efficient and time managing way of casting a vote. Mobile phones facilitate communication and rapid access to information and their diffusion has reached a larger proportion of the population in a short period of time. In this thesis, we propose designing and developing a mobile phone voting system, which allows users to vote spontaneous and timeous, using existing mobile phone networks and technologies via their mobile phones.
57

Implementation of a WCDMA AAA receiver on an FPGA based software radio platform.

Kora, Saju P. January 2001 (has links)
WCDMA promises to achieve high-speed internet, high quality image transmission and high-speed data services with larger system capacity. However, Multiple Access Interference is one of the major causes of transmission impairment, which reduces the link capacity in WCDMA systems. The Adaptive Antenna Array (AAA) technique reduces multiple access interference by directing antenna beam nulls towards the interfering signals by weighting the received signals from all antennas before combining the signals. With the very rapid advancement of wireless personal communications services, a new challenge to the cellular industry is the integration of multiple systems and applications on a single device. A software radio technique offers a possible solution to achieve this goal including international roaming and multiple standard operations within the same geographical area. The main attraction of a software radio is it's flexibility, in that it can be programmed for emerging cellular standards allowing it to be updated with new software without any changes in the hardware infrastructure. A software radio incorporating adaptive array beamforming at the receiver can increase the total carried traffic in a system and transmit power while the probability of call blocking and forced termination can also be decreased. This dissertation examines WCDMA, AAA, power control and software radio techniques in the world of wireless communication systems. Once the theoretical background of CDMA and AAA has been substantiated, the thesis establishes the need for power control in mobile systems by examining simulation results. An AAA receiver with six antenna elements is proposed and evaluated in different environments as a precursor to implementation. It can be inferred that when the link is interference limited, the link capacity can be increased and it has been shown that the AAA receiver with six antenna elements increases the link capacity to about 2.9 times that of the single antenna RAKE receiver. This thesis also examines the basic concepts of VHDL and considers this as the principle means to program reconfigurable core FPGA's in the software radio. A three-layered (PC/DSP/FPGA) software radio test bed is used to implement an AAA receiver. The architecture of the test bed is designed in such a way that it can be used to evaluate the performance of various FPGA based transceivers and coding schemes etc. Many of the desirable features and flexibilities inherent in the software radio concept are available on this test bed and the system has proved to be capable of high speed digital processing and is ideally suited to the development of time critical system components. The bit error rate achieved using the implemented receiver is assessed and compared to simulation results in an environment incorporating Rayleigh fading and AWGN. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.
58

An identification of the market needs and wants of undergraduate students with specific emphasis on the cell phone industry.

Moodley, Perumal Shunmugam. January 2003 (has links)
This study is focused on the cellular communication needs and wants of undergraduate university and technikon students. The study derived its information from a survey of 224 students who, via a questionnaire, were able to detail their present and future cellular communication needs. Among other findings, the results of this survey, revealed the following: • The undergraduate university and technikon student market is not homogenous • Ninety-three percent of university and technikon students in the sample had access to a cellular telephone • Short Message Services (SMSs) and "Please Call Me" services were frequently favoured and used • The market segment is highly brand conscious, preferring specific branded cellular telephones • Despite having a limited access to disposable income (most of which is provided by their parents), respondents spent between R75 and R1 000 per month on their cellular needs.
59

Interference cancellation for collocated wireless radios

Raghavan, Anand. January 2007 (has links)
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008. / Laskar, Joy, Committee Chair ; Cressler, John, Committee Member ; Kornegay, Kevin, Committee Member ; Tentzeris, Emmanouil, Committee Member ; Lee, Chang-Ho, Committee Member.
60

Complex adaptive system simulation of cellular network subscriber behaviour

Nel, Trevor Jon 29 June 2015 (has links)
M.Sc. (Information Technology) / Making changes to a complex system, such as a cellular network, without being well informed about the potential effects of the change could prove to have negative and costly outcomes. In order to diminish the risk of making changes to a real system, a simulation of the real system is a viable and valuable alternative. By creating a simulation of the real system, the effects of changes made can be tested in the simulation instead of the real system. The dissertation presents a model by which subscriber behaviour within a cellular network can be simulated. The model that is introduced to this end is called the Mobile Network Subscriber-Behaviour Simulation (MNSS). Subscriber behaviour is important as it is largely responsible for the variation in traffic within the cellular network. Thus, the research presented in the dissertation seeks to provide a means by which the planning and operation of cellular networks can be enhanced through a better comprehension of network traffic, which is influenced by subscriber behaviour. In the dissertation, specific focus is given to voice traffic, and, as such, the cellular network architecture that was chosen for the model is the GSM mobile network architecture due to its ubiquitous use in carrying voice traffic. The research presented in the dissertation begins with a discussion on the GSM architecture. Subscriber behaviour is simulated through the use of intelligent agents that are configured to interact with one another to form a Multi-agent System. In addition, the subscriber agents interact with, and adapt to, the mobile network component of the MNSS model, which constitutes the formation of a Complex Adaptive System. Therefore, the discussion is subsequently directed towards Artificial Intelligence, intelligent agents, Multi-agent Systems and Complex Adaptive Systems. Using these aforementioned concepts, the dissertation presents the MNSS model and a prototype implementation, as well as a discussion on the results obtained from this. The main purpose of the dissertation is to examine a means by which subscriber behaviour can be simulated in a cellular network, through the use of multiple intelligent agents that interact in a complex system. This is conducted for the express purpose of analysing the change in behaviour of the subscriber agents in relation to changes made to external conditions, such as the underlying cellular network or the behaviour of other subscriber agents.

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