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Design and development of an emergency fire telephone system for the Cape City CouncilVan Tonder, Alister D January 1988 (has links)
Thesis (Masters Diploma(Technology)--Cape Technikon, Cape Town, 1988 / The project entails designing and installing an emergency fire telephone system (EFTS) for the 23 storey Cape Town Administrative Civic Centre. The original system, with its mostly analogue circuitry, has no documentation available, is difficult to maintain and has become unreliable. After considering alternative systems the most economical option was to expand the original system by adding more extension telephones and to redesign the control section. The new EFTS briefly operates as follows: The status of ninety six extension telephones, installed at the emergency exits on each floor, are displayed on a mimic status display which both operators can monitor. Any emergency call can be identified by a green flashing LED and a distinctive bleep. The LED indicates the exact position and number of the telephone in the building, Each operator has a keypad and a two digit numeric display fitted his telephone. The operator can immediately answer incoming calls by pressing the queue button. Calls queue on a first in first out basis. The number of the extension telephone will be displayed on a numeric display. The operator can also select the extension he wishes to contact, by dialling the extension number on the keypad. The EFTS consists of nine printed circuit boards. A rack mounted Microcomputer board, made up of a Motorola MC6809 microprocessor, six 6821 PlAs, 2 kilobyte RAM, up to 16 kilobyte ROM and a watchdog timer controls the EFTS.Two Telephone Controller boards process voice signals and generate logic control signals for the CMOS voice switching circuitry on the Multiplexer Monitor boards. Six Multiplexer Monitor boards switch the two operators to any of the ninety six extension telephones and continuously monitor the extension telephone lines for faults and handset statuses. Noise and over voltage line protection is provided. The multiplexing of the 192 LEDs on the Mimic Status Display is controlled by the Microcomputer board. An unusual principle used in this design is the combination of low frequency AM and audio to affect communication. Two uninterruptable power supplies provide user independence from mains. Software used for the EFTS is written in 6809 Assembly Language. A Real time interrupt controls the Mimic Status Display. Operator actions are interfaced with the program logic by means of hardware interrupts.
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The effects of system response time and cognitive loading on accessing an automated telephone emergency service: examining elderly and young usersKies, Jonathan K. 11 June 2009 (has links)
The user interface for a proposed alternative emergency service was conceived and designed for a standard touch-tone telephone. The service would allow a user to activate an automated, pre-recorded message containing information to aid emergency responders. The user must only press a few specified keys on the telephone key-pad, avoiding the need for verbal interaction with a dispatcher.
The interface was designed in terms of providing the necessary instructions for activation and considering various input strategies and feedback. Icons, written instructions, and voice feedback were employed in the development of a successful and effective interface between the user and the system.
Because the system is expected to attract elderly users and families with young children, the performance and attitudes of these two age groups in regard to a system prototype were examined to determine if the interface was suitable.
A two and eight second initial system response time were imposed upon users to determine any effect these delays might have on user response time, error rate, and subjective attitudes. Additionally, a secondary task, designed to increase cognitive loading was employed to determine if the system is usable while the user is engaged in a dual-task environment. The dependent variables used to gauge the effects of the manipulated variables include the objective measures of user response time and error rate and subjective questionnaire responses.
The results of the study indicate that the elderly adults and young children were able to activate the system successfully. System response time and cognitive loading had no significant effect on user performance or subjective attitudes. Distinct practice effects were observed. Attitude scales indicated satisfaction with the service and its interface. Finally, a significant effect of age was observed on average user response time, with the elderly activating the system quicker than the children. / Master of Science
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Indoor/Outdoor Location of Cellular Handsets Based on Received Signal StrengthZhu, Jian 19 May 2006 (has links)
Indoor/Outdoor Location of Cellular Handsets Based on Received Signal Strength
Jian Zhu
123 pages
Directed by Dr. Gregory D. Durgin
Accurate geo-location is an important emerging technology for public safety, commercial use, and military application. Especially, in the United States, the wireless Enhanced 911 (E911) rules by the Federal Communication Commission (FCC) seek to provide 911 dispatchers with additional information on wireless 911 calls.
This dissertation presents a novel technique for indoor/outdoor location of cellular handsets based on received signal strength (RSS) measurements taken by a cellular handset of the surrounding base stations. RSS location accuracy for different environments is studied as a function of base station separation distance, cell sector density, measurement density, radio propagation environment, and accuracy of measurement. The analytical and experimental results in this thesis serve as a guideline for the accuracy of RSS signature location technology under different conditions. Accurate outdoor to indoor penetration models are proposed and validated for dense urban areas by introducing pseudo-transmitters to simulate the wave-guiding effects in urban canyon environments. A set of location algorithms is developed to improve location accuracy. Furthermore, an algorithm to discriminate between indoor and outdoor users is proposed and validated. The research results demonstrate the feasibility of RSS location techniques to meet the FCCs requirements for E911 accuracy in urban and semi-urban environments. The techniques remain accurate for indoor handsets. The results also suggest that a hybridization of the handset-based GPS method and the RSS signature method may prove to be the most effective solution for locating handsets across a range of environments; including rural, suburban, dense urban, and indoor.
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Measuring Vital Signs Using Smart PhonesChandrasekaran, Vikram 12 1900 (has links)
Smart phones today have become increasingly popular with the general public for its diverse abilities like navigation, social networking, and multimedia facilities to name a few. These phones are equipped with high end processors, high resolution cameras, built-in sensors like accelerometer, orientation-sensor, light-sensor, and much more. According to comScore survey, 25.3% of US adults use smart phones in their daily lives. Motivated by the capability of smart phones and their extensive usage, I focused on utilizing them for bio-medical applications. In this thesis, I present a new application for a smart phone to quantify the vital signs such as heart rate, respiratory rate and blood pressure with the help of its built-in sensors. Using the camera and a microphone, I have shown how the blood pressure and heart rate can be determined for a subject. People sometimes encounter minor situations like fainting or fatal accidents like car crash at unexpected times and places. It would be useful to have a device which can measure all vital signs in such an event. The second part of this thesis demonstrates a new mode of communication for next generation 9-1-1 calls. In this new architecture, the call-taker will be able to control the multimedia elements in the phone from a remote location. This would help the call-taker or first responder to have a better control over the situation. Transmission of the vital signs measured using the smart phone can be a life saver in critical situations. In today's voice oriented 9-1-1 calls, the dispatcher first collects critical information (e.g., location, call-back number) from caller, and assesses the situation. Meanwhile, the dispatchers constantly face a "60-second dilemma"; i.e., within 60 seconds, they need to make a complicated but important decision, whether to dispatch and, if so, what to dispatch. The dispatchers often feel that they lack sufficient information to make a confident dispatch decision. This remote-media-control described in this system will be able to facilitate information acquisition and decision-making in emergency situations within the 60-second response window in 9-1-1 calls using new multimedia technologies.
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