Thèse--Méd.--Reims, 1974. N°: N° 14. / Bibliogr. ff. I-VIII.

Building designers aim to create buildings with high quality internal environments which are energy and cost efficient in their use. Failure to attain these objectives simultaneously can lead to reduced building occupant productivities. An important aspect of the building services system which can have a major effect on the provision of occupant comfort within a building is the adopted control strategy. The research project investigated the use of fuzzy control strategies as a means of achieving good standards of comfort provision for occupants while maintaining or improving energy and cost efficiencies for the operation of the building HVAC services. This represented a multi-variant controls objective which was capable of being fulfilled by a fuzzy controller. A one zone building computer model was developed using Matlab and Simulink software as a platform for the development of fuzzy control strategies. The model incorporated building services Heating Ventilating and Air-Conditioning (HVAC) system models. A Proportional + Integral + Derivative (PID) control strategy was used as a benchmark control methodology against which to compare the developed fuzzy control strategies. Three types of fuzzy controller were developed during the course of the research project. These were a Proportional Derivative Fuzzy Controller (PDFC), a Fuzzy Ventilation Controller, and the Fuzzy High Level Controller. The PDFC used the inputs of error and rate of change of error from a specified zone environmental condition set point in much the same way as a PID controller would to control the HVAC plant. Simulation results indicated that the PDFC control strategy was capable of achieving performance levels equal to the conventional PID control strategy. The Fuzzy Ventilation Controller was used to control the rate of fresh outside air entering the building zone through the mechanical ventilation system in order to make use of the 'free' cooling and dehumidification available by purging the indoor air when possible. Simulation results showed improvements in the indoor environmental quality provided, and the energy efficiency and cost efficiency of running the HVAC plant. Finally, the Fuzzy High Level Controller used a fuzzy supervisor to control the actions of the fuzzy ventilation controllers. Simulation results showed that the fuzzy supervisor was able to improve the comfort conditions provided and the energy and cost efficiencies of the operation of the HVAC plant when compared to the use of the fuzzy ventilation control strategies alone.

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This research focussed on the identification, evaluation and recommendation of passive design strategies suitable for housing design in hot and dry climates in India. The term 'passive' refers to those design techniques which, in order to enhance thermal comfort, utilize the favourable and mininimize the unfavourable elements of the local climate. The objective of the research was to determine means by which reliance on mechanical means of achieving comfort and associated socio-economic costs can be minimized. The thesis is divided into two parts. The first part identifies and evaluates the passive design techniques used in the dwellings of pre-industrial and post-industrial cities located in hot and dry region in India. Climate, environmental problems (primarily cooling), and indoor comfort criteria were analysed to establish preliminary criteria for evaluating the thermal performance of design techniques. The main objective was to enable designers to identify those techniques which can be used in contemporary dwelling designs. The second part proposes strategies to incorporate passive techniques in contemporary housing design. General strategies recommended at various levels of design include the following: -minimize solar gain -minimize conductive heat flow -promote ventilation -minimize internal heat gains -promote radiant cooling -delay periodic heat flow -promote evaporative cooling -control high velocity wind -control glare These strategies, which recognize the comfort-related needs of dwelling occupants, promote the use of local construction practices. The application of passive techniques presents architects with a considerable scope for creativity in housing design. However, at the outset, it is necessary to define priorities in the selection of design strategies, and to ensure these priorities are addressed through each level of design. The strategies selected in this thesis emphasize the need for minimizing heat gain during day time, and maximizing heat loss at night. It is concluded from this research that the application of passive techniques in contemporary housing design allows for maintenance of most thermal comfort needs, thereby reducing reliance on mechanical means of control. At the same time, the use of passive techniques provides a potential for the housing designs to respond effectively to certain socio-cultural needs of the occupants. / Applied Science, Faculty of / Architecture and Landscape Architecture (SALA), School of / Received degree under the name Bhatia / Graduate

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Postoperative pulmonale Komplikationen (PPC) stellen den Hauptgrund für erhöhte Morbidität und Mortalität sowie eine längere stationäre Liegedauer nach chirurgischen Eingriffen dar. Die Elektrische Impedanztomographie (EIT) ermöglicht als strahlungsfreie Methode die bettseitige Visualisierung der regionalen pulmonalen Ventilation in einem thorakalen Querschnittsbereich über den zeitlichen Verlauf. Die Hauptfragestellung dieser Studie war die perioperativen Veränderungen der regionalen pulmonalen Ventilation bei spontanatmenden Patienten nach abdominalchirurgischen Eingriffen in Allgemeinnarkose bis in die späte postoperative Phase zu untersuchen. Zusätzlich untersuchten wir die Lungenfunktion mittels Spirometrie. Wir nahmen eine Verschiebung der pulmonalen Ventilation in dorso-ventraler Richtung an, sowie eine postoperativ reduzierte Vitalkapazität, z.B. durch Atelektasen oder Pleuraergüsse. In die prospektive Observationsstudie wurden 36 erwachsene Patienten eingeschlossen, die sich einem elektiven abdominalchirurgischen Eingriff unter Allgemeinanästhesie unterzogen und ein mittleres Risiko gemäß ARISCAT Score für die Entwicklung von PPC aufwiesen. Präoperativ, sowie am 1. und 3. postoperativen Tag erfolgte die Untersuchung der pulmonalen Ventilation mittels EIT in Spontanatmung, Errechnung des Center of Ventilation (COV), sowie eine Lungenfunktionsprüfung mittels Spirometrie. Nach abdominalchirurgischen Operationen kam es zu einer statistisch signifikanten und bis zum 3. postoperativen Tag anhaltenden Verschiebung der pulmonalen Ventilation nach ventral (COVy präop. 16,5; 1. Tag postop. 17,8; 3. Tag postop. 17,4). Zudem zeigte sich eine anhaltend reduzierte Forcierten Vitalkapazität in % vom Sollwert (FVC%Soll): präop. 93%; 1. Tag postop. 58%; 3. Tag postop. 64%. Am 3. postoperativen Tag bestand unter forcierter Atmung eine negative Assoziation zwischen der Änderung des COVy und der Änderung der FVC%Soll. PPC traten bei 10 Patienten in Form von respiratorischer Insuffizienz, Atelektase und Pleuraerguss auf. Bei diesen Patienten zeigte die EIT keine komplikationsspezifischen Bilder. Abdominalchirurgische Operationen hatten hat einen relevanten Einfluss auf die postoperative regionale Lungenventilation und somit auf die Entstehung von PPC. Die EIT hilft die Entstehung von PPC besser zu verstehen und Strategien zur Vermeidung solcher im klinischen Alltag zu implementieren. / Postoperative pulmonary complications (PPC) are the main reason for increased morbidity, mortality and length of stay in hospital after surgical interventions. Electrical impedance tomography (EIT) is a radiation-free method that can visualize regional pulmonary ventilation within a transversal section of the lung in real-time. Main goal of this study was the examination of perioperative change in regional pulmonary ventilation until the late postoperative period in spontaneously breathing patients after abdominal surgery receiving general anesthesia. In addition we examined pulmonary function using spirometry. We hypothesized a shift of pulmonary ventilation in dorso-ventral direction and a postoperatively decreased vital capacity e.g. as a result of atelectasis or pleural effusion. In this prospective observational study 36 adult patients that underwent elective abdominal surgery under general anesthesia were included. According to ARISCAT score they showed an intermediate risk for the development of PPC. Preoperative, at the 1st and 3rd postoperative day there was the examination of pulmonary ventilation using EIT, calculation of the center of ventilation (COV) and examination of pulmonary function using spirometry. After abdominal surgery there was a significant shift of pulmonary ventilation in ventral direction. This continued until the 3rd postoperative day (COVy preop. 16.5, 1st postop. day 17.8, 3rd postop. day 17.4). In addition forced vital capacity in %predicted (FVC%predicted) was decreased: preop. 93%, 1st postop. day 58%, 3rd postop. day 64%). On the 3rd postoperative day changes in COVy were negatively associated with changes in FVC%predicted during forced breathing. 10 patients developed PPC (respiratory insufficience, atelectasis, pleural effusion). These patients did not show any characteristic image in EIT-imaging. Abdominal surgery had a relevant influence on postoperative regional pulmonary ventilation and as a result of that on the development of PPC. EIT helps to understand the development of PPC in a better way and to implement strategies for avoiding PPC in everyday clinical work.

Tests were performed to determine and compare the aspirating effectiveness of 10- to 24-inch sizes of a stationary siphoning type of automatic roof Ventilator. The basic principles of Ventilator design were studied critically, and suitable apparatus and methods of carrying out the tests were designed accordingly. One series of tests consisted of mounting a Ventilator on a ten-foot stack at the mouth of a calibrated wind tunnel, and by measuring with a Velometer the Velocity of the air traveling up the stack, determining the volume of air drawn through the stack while winds of from two to seven miles per hour were blowing across the ventilator. The second series of tests was identical with the first, except that the Ventilator was removed and the wind was directed across the open end of the stack. Stacks and ventilators of sizes 10, 12, 14, 16, 18, 20, and 24 inches were tested. All test results are based on zero difference in temperature between the wind tunnel air and the stack air and on no friction loss in the stack. The capacities listed are for standard air at 70°F and a barometric pressure of 29.92 inches of mercury. The tests revealed several interesting facts. The open stacks were found to be more effective than the Ventilators when the wind Velocity across the Ventilators was less than about 4.5 miles per hour; but the Ventilators proved better than the open stacks at wind Velocities above 4.5 miles per hour. For the series of Ventilators tested, the relationship between discharge capacity and wind Velocity across any given ventilator was found to be approximately linear. It was observed that small disturbances in the air currents around the Ventilator head seriously affect the discharge and that for maximum effectiveness, it is necessary to have ample window opening in the room to be ventilated. / Master of Science

This thesis explores the opportunities and limitations of steel construction and connection to the outdoors through a sports facility for the city of Blacksburg, Virginia. The program being that of an indoor soccer facility allows for the steel to express its ability to span great distances with a very fine and visually delicate structure. Cables express the steel's strength in tension. The structure is clearly expressed and easily understood by anyone who enters the facility. The building's indoor connection to the outdoor environment is achieved through the study and implementation of several strategies that not only enhance the visual and thermal comfort levels of those people in the facility but will also reduce the building's operating costs. One of the main strategies utilized to achieve this enhanced comfort level is that of natural ventilation. This will contribute to the overall air quality of the interior space and bring a refreshing breeze to the athletes and spectators of the facility. A second important design strategy is the utilization of natural light brought through and interacting with the translucent roof and steel structure. / Master of Architecture

Environmentally sensitive architecture is rapidly staking its claim on the building community. The structures that are being constructed to fulfill the increasing public demand for "green buildings" are not currently utilizing their unique potential to physically portray their inherent characteristics to be naturally and technologically advanced. Environmentally sensitive architecture has the potential and arguable responsibility to physically react to and portray the natural factors that they are programmatically and technically adapting to. / Master of Architecture