M.S.

This thesis describes a two part research program in which the applicability of subjective ratings to the selection of independent variables was evaluated. The first portion of the research reviewed a case study involving the application of complex system investigation to the development of a telephone inquiry system. A telephone inquiry system is one in which users seek information in a data base by calling the system, listening to information presented by a synthetic voice, and directing movement through the database with commands on the telephone keypad keys. The complex system investigation method used included identifying the independent variables by brainstorming, then reducing the list by subjecting the variables to literature review, feasibility analysis, relevance analysis, and subjective ratings of the factors based on a prototype system. Variables which were not likely to have an immediate impact on human performance in the system were set to a constant value. The use of subjective ratings to select independent variables stems from the need to reduce large numbers of independent variables to a list which can be used as candidates for a screening study. The result of the case study was a list of 19 candidate factors suggested for implementation in a screening study. The second portion of the research describes an experiment in which 5 independent variables ( number of steps in a search, adapting speech rate, transaction summary, native/non-native, and sex of the voice) were chosen to represent the 19 candidate factors in an experiment testing the validity of the ·subjective ratings technique. The results indicated that the subjective ratings of the prototype system were effective in predicting performance and subjective ratings. The impact of these results on the methodology and telephone inquiry systems is also discussed. / M.S.

Indiana University-Purdue University Indianapolis (IUPUI) / Mobile telephones are impacting societies around the world and text messaging, short type-written messages sent via mobile phones, has also garnered international research efforts. Research demonstrates that text messages are being used primarily to commence, advance, maintain or otherwise impact interpersonal relationships. The present study probes relational benefits of text messaging within familial and fraternal contexts. Specifically, the study seeks to answer the research question: How does text messaging impact feelings of “connectedness” (IJsselsteijn, van Baren & van Lanen, 2003, p. 928) within “strong-tie” (Howard, et. al., 2006), dyadic relationships? Findings from nineteen respondent interviews show that texting becomes a channel through which dialectical tensions in relationships are played out. Respondents use texting to both assert autonomy and to maintain connectedness with relational partners. Several participants noted that financial issues were an important consideration but nevertheless subscribed to texting services. Users also perceived texting as more constant and more private than mobile voice interaction. Romantic pairs vis-à-vis non-romantic dyads perceived the benefits of text messages differently.

Thesis (M.B.A.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 148-152).

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2007. / The work presented in this Thesis relates to the increased capabilities of the mobile Internet and the possible use of cellphones as an enhancement to video surveillance systems. The focus of the Thesis is on the delivery of live video content to Java enabled cellphones. The various characteristics, capabilities and limitations of the mobile networks- and phones are investigated. Various options for streaming video content to cellphones are also explored. The design and implementation of a digital surveillance system with the ability to stream live video to a cellphone is presented. Two versions of the streaming protocol are developed and implemented in cellphone applications, with which the video stream can be viewed. An evaluation and real-life testing of the applications are presented. Recommendations regarding further enhancements are provided.

D.Phil. / A modern day N-P complete problem is the assigning of frequencies to transmitters in a cellular network in such a manner that, ideally, no two transmitters in the same cell or neighbouring cells use the same frequency. Considering that an average cellular network provider has over 29 000 transmitters and only 55 frequencies, choosing these frequencies in an optimal way is a very difficult computational problem. Swarm intelligence allows the acceptable minimization and optimization of the frequency assignment problem (FAP). Swarm intelligence is a concept modelling the processes in natural systems such as ant colonies, beehives, human immune systems and the human brain. These systems are selforganizational and display high efficiency in the execution of their tasks. A number of simple automated agents interacting with each other and the environment form a collective. Specifically, there is no "central agent" directing the others. A collective can display surprising intelligence which emerges out of the interaction of the individual agents. This collective intelligence, referred to as swarm intelligence, is displayed in ant colonies when ants build elaborate nests, regulate nest temperature and efficiently search for food in very complex environments. In this thesis a proposal is made to utilize swarm intelligence to build a swarm automatic frequency planner (swarm AFP). The swarm AFP produces frequency plans that are better, or on par with existing frequency planning tools, and in a fraction of the time. A swarm AFP is presented through an in-depth investigation into complex adaptive systems, agent architectures and emergence. Based on an understanding of these concepts, a swarm intelligence model called ACEUS is constructed. ACEUS forms the platform of the swarm AFP. It is a contribution to multi-agent technology as it is a new multi-agent framework that exhibits swarm intelligence and complex distributed computation. What differentiates ACEUS from other multi-agent technologies is that ACEUS works on the basis that the tasks or constructions that have been created by the agents actually guide the agents in their endeavours. There is no centralised agent controlling or guiding the process. The agents in ACEUS receive information and stimulation from their tasks or constructions in the environment. As these constructions or tasks alter the environment, the agents receive stimulus from the changing environment and then react to the changing environment. The changing environment acts as an emergent guiding force to the agents. This is the important contribution that stigmergy contributes to ACEUS. Utilizing this concept, ACEUS is used to create a swarm AFP. The swarm AFP is benchmarked against the COST 259 Siemens benchmarks. In all the COST 259 Siemens scenarios the swarm AFP produced the best results in the shortest time. The swarm AFP was also tested in a real cellular network and the resulting statistics before and after the swarm AFP implementation are presented.

The purpose of this research is to determine the linearity and monotonicity of the THS5651IDW digital to analog converter (DAC), a prototype of the future Texas Instruments TLV5651, 10-bit, 125 MHz communication DAC. Testing was conducted at the Texas Instruments facility on Forest Lane, Dallas, Texas. Texas Instruments provided test equipment, software and laboratory space to obtain test data. Analysis of the data found the DAC to be monotonic since the magnitude of the differential nonlinearity (DNL) was less than ± 1 least significant bit (LSB) and the integral nonlinearity (INL) was less than ± 0.5 LSB. The study also showed that the DAC has primarily negative DNL although the DNL is well within the desired specification.

Knowledge in organizations today is considered as one of the most important assets the organization possesses. A considerable part of this knowledge is the knowledge possessed by the individuals employed by the organization. In order for intelligent systems to perform some of the tasks their human counter parts perform in an organization the intelligent systems need to acquire the knowledge their human counter parts possess for the specific task. To develop an intelligent system that can perform a specific task in an organization, the knowledge needed to perform the task will have to be extracted from the individuals in the organization via knowledge acquisition. This knowledge will then be presented so that the intelligent system can understand it and perform the task. In order to develop an intelligent system an ontology representing the domain under consideration as well as the rules that constitute the reasoning behind the intelligent system needs to be developed. In this dissertation a development environment for developing intelligent systems called the Collaborative Ontology Builder for Reasoning and Analysis (COBRA) was developed. COBRA provides a development environment for developing the ontology and rules for an intelligent system. COBRA was used in this study to develop a Cellular telecommunications Network Consistency Checking Intelligent System (CNCCIS), which was implemented in a cellular telecommunications network. / Prof. E.M. Ehlers

The work in this thesis concerns the use of reinforcement learning solutions to re-source allocation problems in channelised cellular networks. The methodology of re-inforcement learning techniques was chosen for application to these problems due to its capability of finding efficient policies in a fully on-line, adaptable manner, without requiring specific environment models. All of the presented agent architectures are assumed to simultaneously learn and perform network control functions in a totally on-line and unsupervised manner, and agents are developed with a view to real-world implementability by focussing on techniques that have low resource requirements and make use of only local system information.

This two years master’s thesis in Library and Information Sciences aims to investigate and put the services of 118100 Svar På Allt (SPA, an SMS mobile question and answer service) and Fråga biblioteket (FB, a library operated e-mail reference service) into the context of the reference encounter. Questions sent to SPA and their subsequent answers are analysed, and part of these questions are forwarded to FB for comparative studies. Both of the formats are compared to the reference encounter as a whole. The framing of the question originates in the assumption that there may be a need for further negotiation of the questions submitted to the aforementioned formats. Do SPA and FB constitute formats different enough from the reference encounter to imply that the question at hand already has gone through the apropiate negotiations? These compressed and asynchronous reference services are not only compared to the synchronous reference, but are also examined as reference services in their own right. How does the e-mail reference and the SMS services fare against each other and the “regular” reference encounter? Findings in the analysis are subjected to appliable INSU theories, especially Robert S. Taylors thoughts on question negotitation and Nicholas Belkins et al regarding anomalous states of knowledge. Further major contributors are Marie L. Radford concerning the reference encounter and Reijo Savolainen on everyday information practices. The study found several occasions where a personal, or at least synchronous, reference encounter would have been decidedly more helpful than that of the electronic services. However, the larger majority of the questions analysed turned out to be completed in formulation for the compressed, asynchronous format. The e-mails of FB can to some extent work as an intermediary service since it is more allowing lengthwise than SPA and gives more of an opportunity to redirect towards more exhaustive sources.