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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.
61

Natural ventilation of buildings : time-dependent phenomena

Coomaraswamy, Imran Ajay January 2011 (has links)
No description available.
62

Framtidens toalettstol

Ekström, Mattias, Axelsson, Pierre January 2008 (has links)
oduer free toilet
63

Hur uppnår vi god inomhusmiljö i förskolan idag?

Björkman, Amelie January 2014 (has links)
Abstract: This thesis work has been conducted at the Real Estate Department in Halmstad. The department consists of a construction/project management-unit and an operation/management-unit. Like many other towns in Sweden, Halmstad has had a long lasting problem with indoor environment. Not at least at their preschools. Today they are constructing from current building regulations. They have learned from negative experiences which have occurred in the indoor environment in older buildings. Focus is now on healthy materials, like low emission value, energy efficiency and optimization of the building, but still with soft parameters such as cleaning, interior and choice of materials. The fixtures is provides by the real estate department and the furnishings are provides by the children and youth administration. Together they are trying to provide a great indoor environment. I have, together with the real estate department and the children and youth administration of Halmstad, investigated how to provide a good indoor environment in the preschools with small funds. In my thesis there is one theoretical part with a questionnaire survey of how the preschool staff is experiencing their indoor environment to determine where the problems often start. And a practical part with measurements to try and come down to a result that analysis the cause of the problems and also to make sure that the ventilation systems are fulfilling projected values. The measurements and the questionnaire surveys was made at Lokes preschool in Frösakull, Askens preschool in Oskarström and Gullbrandstorps preschool. There were some differences between the staff-responses at the three different preschools. At Askens preschool they feel that the premises are cleaned poorly. At Gullbrandstorps preschool they feel that the indoor-air is bad because they can´t open the windows. The only common factor is the problems they have with the noise the children makes, which unfortunately is normal and specific for the activity. The particle measurement shows that Askens preschool is the one with the most particles in the indoor-air, which can be the results of poor cleaning och materials that are hard to clean. The airflow measurements didn´t show any unusual values, at those preschools where the measurements went well.
64

THE INFLUENCE OF VENTILATION MODELING ON PRODUCTION PLANNING

Gherghel, Cristian 30 April 2010 (has links)
Abstract The main objective of a ventilation system is to provide the quality and quantity of the airflows throughout the mine and to ensure safe and health conditions for the workers to the level specified by the mining regulations. In uranium mines the planning and operation of the ventilation systems have a large impact on production due to the fact that the first engineered step to control radiation contamination is with ventilation. The techniques used to maintain good air quality in uranium mines are based on providing very large volumes of air, maintaining the residence time of the air at a minimum in all working areas, guaranteeing zero recirculation of the air and designing a highly flexible ventilation system. This thesis introduces a general approach that can be use in ventilation planning for uranium mines and outlines the importance of conducting medium and long term ventilation planning exercises. Case studies are presented to illustrate the use of ventilation modeling software, spreadsheets, scheduling software and mine design software in order to manipulate data in ventilation planning exercises. The results from these exercises will indicate any required additional infrastructure. A section of this thesis deals with simulation exercises used for validation of the design work. Once the new infrastructure is in place and access to reliable field date is available, the models are calibrated and validated to permit further refinement of the ventilation system. This work has demonstrated how one can effectively design, asses and manage underground mine ventilation systems with the help of ventilation modeling software, when such a tool is properly used through calibration and validation exercises. The methodology for the reconciliation between ventilation and production planning proposed in this thesis will assist the uranium mining industry in maintaining the health and safety of the workers underground while efficiently achieving economic production targets. / Thesis (Master, Mining Engineering) -- Queen's University, 2010-04-28 11:36:13.727
65

Preferred building orientation for naturally ventilated buildings

Zemanchik, Normand Joseph January 1992 (has links)
Determining optimum building orientation for naturally ventilated buildings is an important concept. Obtaining the optimum orientation will determine the success of the performance of a naturally ventilated building. / This project deals with obtaining the preferred building orientation for 10 regional weather stations across the province of Ontario. Different methods were utilized to obtain the preferred building orientation: the average ventilation rate method, the percentage of ventilation rates above and below the minimum summer ventilation rates, and the consecutive hours method, ie. the number of weather events that are below the minimum summer design ventilation rate for a specific building configuration. The analysis involves six building orientations (0$ sp circ$, 30$ sp circ$, 60$ sp circ$, 90$ sp circ$, 120$ sp circ$, and 150$ sp circ$) with respect to North, and exterior temperatures greater than or equal to 20$ sp circ$C, 25$ sp circ$C, or 30$ sp circ$C. / Optimizing building orientation, to minimize the number of weather events where the ventilation rates are below the summer design ventilation rate is the general goal of this research work. / A statistical analysis was carried out based on the results obtained from the data for the frequency of ventilation rates versus the ventilation rates below the summer design ventilation rate, for all 10 Ontario weather stations, for temperatures greater than or equal to 20$ sp circ$C, and all six building orientations. The output of the statistical analysis showed that for the above mentioned temperature range, that there is a relationship between the ventilation rates below the design summer ventilation rate and building orientation.
66

Analytsis and performance optimization of commercial chiller/cooling tower systems

Liu, Hubert H. 08 1900 (has links)
No description available.
67

Psychrometric application to closed loop vapor degreasing

Gross, Bryan Eric 12 1900 (has links)
No description available.
68

A computer model for predicting natural ventilation rates

Nutt, David William 05 1900 (has links)
No description available.
69

Ventilation distribution in the lung during cyclic breathing

Shykoff, Barbara Ellen. January 1984 (has links)
The dynamic distribution of pulmonary ventilation was studied both theoretically and experimentally. The human lungs were simulated as two compartments driven by independent cyclic pleural pressures. The distribution of tidal volume depended primarily on the regional pressures, but dissimilar pressure swings generated sequential flows. A model of the tracer dynamics in the lung during a breath showed that the ventilation per unit volume was proportional to the time derivative of krypton-81m activity normalized by the activity itself. In gamma camera measurements, the average flow distribution was independent of frequency and tidal volume, but the flow per unit volume in left lateral decubitus subjects was greater in the dependent than the non-dependent lung, and sequential flows were evident. However, lung sound amplitudes were in phase over the dependent and non-dependent regions, varying as the square of the airflow at the mouth. The frequency composition of the sounds remained constant. Thus, nonhomogeneous pleural pressure swings appear to control the dynamic distribution of ventilation. This time-varying quantity can be measured using a short-lived isotope but not directly with lung sounds.
70

A study of the wind pressure forces acting on groups of buildings

Soliman, B. F. January 1976 (has links)
No description available.

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