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Improving shade consistency in vinyl floor tile productionNixon, Peter John January 1977 (has links)
No description available.
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Investigating annealed glazing response to long-duration blastJohns, Robert January 2016 (has links)
The transient dynamic response of annealed glazing to blast loading is a complex phenomenon dependent upon explosive proximity, glazing material properties and structural arrangement. With positive pressure durations in excess of 100ms, long-duration blasts produce substantial impulse and dynamic pressures. Annealed glazing accounted for ~90% of UK building glass at the end of 20th century with similar levels of utilisation the world over. As a brittle material, it cannot undergo plastic deformation resulting in sudden failure under tension. As the minimum level of glazing resistance to blast, annealed glazing breakage introduces significant hazard to a building’s occupants and those in surrounding regions. The original contribution of this PhD has been to investigate and quantify annealed glazing response to long- duration blast with an emphasis on the influence of structural arrangement via variable glazing thickness, area, aspect ratio and edge support conditions. Eighteen full-scale blast trials were conducted where results have shown that notionally elastic supports can prevent glazing breakage versus rigidly clamped arrangements. Edge conditions were also found to exert an important influence on both fragmentation and potential fragment hazard with elastic supports shown to produce large, angular fragments versus rigid arrangements which generated significant cracking and smaller fragments. The quantification of peak panel deflection, breakage time and applied breakage impulse has demonstrated significant variability with the influence of edge supports and aspect ratio found to be dependent on proximity to a threshold area for a particular thickness. This research has also examined computational models of glazing response and blast wave propagation produced with the Applied Element Method (AEM) and CFD. Comparisons with experimental data have shown reasonable levels of agreement, indicating the potential to provide future predictive capacity.
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An experimental and theoretical investigation into the design, development and performance of evacuated glazingFang, Yueping January 2002 (has links)
No description available.
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Moisture conditions in external timber cladding : field trials and their design implicationsDavies, Ivor January 2011 (has links)
This thesis describes the development of technical guidance on timber facade design. The study involved a state-of-the-art review; an exposure trial of external cladding made from Sitka spruce (Picea sitchensis) and the production of construction details and associated information. It was undertaken because timber is an increasingly common cladding material in the UK, being used on low-rise residential buildings and for medium-rise and non-domestic buildings. The risks have, therefore, increased but this is not reflected in published guidance. Sitka spruce was used due to its availability in the UK and its similarity to Norway spruce (P. abies) which is widely used for cladding in Scandinavia. The exposure trial indicated that the moisture content range in timber facades is wider than accepted. The minimum moisture content of around 10% appears to be similar for all types of timber cladding and all species. The maximum appears to vary between species according to their fibre saturation point and is influenced by construction detailing and workmanship. A preliminary model of these interactions is proposed. From a theoretical standpoint, the moisture conditions observed in the trial mean that the (commonly quoted) mean moisture content is all but irrelevant. The mode is a more representative statistic as in most cases the data are skewed towards the fibre saturation point for the species concerned. Most detailing combinations had a moisture content near to the fibre saturation point throughout the winter. Sitka spruce is, therefore, only suitable as external cladding in the UK if preservative treated. Around 40 construction details were produced. They integrate, for the first time, all of the performance requirements applicable to low- and medium-rise timber facades in the UK. The work's key benefit is that the guidance arising from this study rationalises and improves facade design. Further research is, however, needed to validate the moisture content model and extend it to other timber species.
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A novel clear foil cushion construction incorporating an additional water layerXie, Fei January 2011 (has links)
Pneumatic clear foil cushion systems, notably as ETFE foil cushions have been developed as an alternative technology to large-scale glass glazing systems for wide-span buildings. The systems display better thermal performance and have advantages of extremely low dead-weight constructions compared to conventional glazing systems, and thereby the increasing popularity of foil cushion cladding systems have been witnessed in the last decades. However due to their lightweight and thinness, the thermal behaviour of architectural foil membranes exhibits a high responsiveness to variations in external conditions. For this reason, it is argued that the reliable prediction of the thermal environment experienced in a space enclosed by a tensile membrane skin construction would require a bespoke modelling of the dynamic thermal behaviour of such a construction at first. Building envelopes clad with such cushions, such as the famous Eden project in the UK, need a dynamic system to control overheating in summer. A cooling liquid layer constructed within a clear multi-layer toil cushion envelope is proposed in this thesis. It enables rapid cooling effects on the building envelope. The system is based on an evaporative cooling mechanism and is integrated with the inflated cushion to provide desired cooling effect eco-friendly. The implications of the forms and configurations of clear foil cushion constructions with and without a cooling liquid layer in the overheating control were evaluated in this research project. Data were collected from a series of experiments to ascertain the effects of the additional cooling water layer on heat transfer processes within the foil skin construction. The results demonstrated that the thermal behaviour of a foil penal depended mainly on surface convection and radiation heat transfer and the cooling performance of the water layer within the foil skin constructions was evident. The initial experimental outcomes were valuable for the design of such novel dynamic cooling systems. In order to assess the effect that different pneumatic foil skin constructions with a water layer might have on thermal conditions inside the enclosed space, the thermal behaviour of full-scale indoor double-layer foil cushion enclosure and triple-layer foil skin construction, with varying evaporative cooling integrative ways and foil skin constructions, were tested during the course of this research. The test datasets were compared according to the research objectives and with the environmental control strategy proposed at the initial design stages. The investigated thermal behaviour of the foil skin constructions incorporating a water layer serves as a reference basis for the analytic modelling of the tested double and triple-layer foil skin constructions in order to predict their surface temperatures and the solar radiation directed into the space they enclose. The approach is based on a detailed modelling of the radiative and convective heat transfer processes affecting the membrane surfaces. These prediction results derived from the model were compared against the environmental data obtained on the test rigs. The developed analytical model is only tentative, as some thermal transfer processes, such as long wave radiation exchanges between the foil sheets, have not been accounted for in this model. Further work is required to develop this model in order to appreciate the thermal performance of such novel foil cushion constructions more precisely and extend their building applications.
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PHerc. 698 Cr. 3-4: A New EditionBarney, Justin Asay 01 June 2015 (has links)
The following is a new edition of PHerc. 698 cr. 3-4, including an introduction, English translation and commentary. An in-line reprint of PHerc. 19, including a new English translation, is also included for continuity of thought and language.
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Relationship Between Future Time Orientation, Adaptive Self-regulation, And Well-being: Self-type And Age Related DifferencesGuler-edwards, Ayca 01 June 2008 (has links) (PDF)
The aim of the present study was to investigate: (a) self and age related differences in time perspective and future time orientations / (b) age differences in adaptive self-regulation / and (c) the contribution of future and self orientations and adaptive self-regulation to well-being. A questionnaire consisting of measures concerning future outlook and time perspective, adaptive self-regulation, self-construals, goals and subjective well-being variables was administered to 404 adults (191 young, 128 middle-aged, 85 older). Also, short structured interviews about time, future, end of life and age were conducted for descriptive and exploratory purposes with nine individuals, three individuals from each age group. On the basis of the results, it was concluded that, (1) older adults had less open and planful, but more anxious future outlook than younger adults, and middle-aged adults had a time perspective more like older adults&rsquo / (2) there is a difference in the content of the goals reported by each age group, and total number of goals reported by older adults was lower than the number of goals reported by young and middle-aged adults / (3) for all age groups, balanced type (i.e., related-individuated, as defined by the Balanced Integration and Differentiation, BID, model) individuals had the most favourable future outlook, and only balanced-type individuals at young, middle and older ages did not differ from each other in terms of having the most favourable future outlook / (4) balanced type individuals reengaged into other goals more than the unbalanced type individuals when they were faced with an unattainable goal / (5) goal reengagement increased with having more open future time perspective, and the contribution of open future time perspective to goal reengagement was much more for middle-aged and older adults than younger adults / (6) self orientations, future time perspective and goal reengagement contribute to well-being, and contributions of future time perspective and goal reengagement to well-being after the contribution of self orientations were considerable only for young and middle-aged adults / (7) gender was not found to have a significant effect on goal reengagement and well-being, but women had slightly more anxious and fatalistic future attitudes than men.
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Roles Of Basic Personality Traits, Schema Coping Responses, And Toxic Childhood Experiences On Antisocial, Borderline, And Psychopathic Personality CharacteristicsOncul, Oznur 01 August 2008 (has links) (PDF)
The purpose of the present study was to investigate the roles of basic personality traits, schema coping responses, and toxic childhood experiences on antisocial, borderline, and psychopathic characteristics. Considering the gap in the literature regarding the community samples, the present study also included a non-criminal, besides the criminal sample, in order to observe the differences among the associated variables related to the characteristics of suggested personality disorders. In this way, it was aimed to obtain a general idea about the protective factors from offending. Consequently, the non-criminal sample consisted of 146 participants (78 females and 68 males) and the criminal sample included 131 participants (42 females and 89 males. Data was collected through a demographic form and a package of inventories. In general, the results yielded that a dysfunctional family environment, whether traumatic or non-traumatic seems to play a crucial role in the development of characteristics of personality disorders. Moreover, basic personality traits and coping responses are also observed to affect the behavioral presentation of these characteristics. The findings of the present study is generally in line with the literature suggesting that, dimensional approach to personality disorders, by revealing the sub-clinical features and providing a deeper focus to the underlying dynamics in each personality disorder, have several implications in both clinical and forensic area. The results, as well as their implications and limitations, are discussed
with reference to the recent literature. Finally, suggestions for further research are mentioned.
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Effects Of The Soil Properties On The Maximum Dry Density Obtained FroArvelo, Andres 01 January 2004 (has links)
In the construction of highways, airports, and other structures, the compaction of soils is needed to improve its strength. In 1933 Proctor developed a laboratory compaction test to determine the maximum dry density of compacted soils, which can be used for specifications of field compaction. The Compaction of soils is influenced by many factors, the most common are the moisture content, the soil type and the applied compaction energy. The objective of this research is the analysis of the maximum dry density values based on the soil classification and characterization. The method of choice in the determination of the maximum dry density from different soils was the Standard Proctor Test following the procedure for the standard Proctor test as is explained in ASTM Test Designation D-698. From this investigation, the maximum dry density of eight types of sands was obtained, the sands were classified by using the Unified Soil Classification System. The influence on the maximum dry density of the type of sands, type of fines, amount of fines and distribution of the grain size was determined, followed by a sensitivity analysis that measured the influence of these parameters on the obtained maximum dry density. The research revealed some correlations between the maximum dry density of soils with the type of fines, the fines content and the Uniformity Coefficient. These correlations were measured and some particular behavioral trends were encountered and analyzed. It was found that well-graded sands have higher maximum dry density than poorly graded when the soils have the same fines content, also it was encountered that plastic fines tend to increase the maximum dry density.
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Retrofit electrochromic glazing : a longitudinal case study of occupant experienceWaskett, Ruth Kelly January 2016 (has links)
Electrochromic (EC) glazing has emerged as an alternative to traditional forms of glazing. It has the potential to enable occupants to control daylight ingress without the use of blinds, giving users more access to daylight with all its inherent benefits. Research efforts to date have been mainly focussed on the potential of EC glazing as an energy saving technology through the reduction of electric lighting and air conditioning energy loads, using scale models, computer simulations and full scale test rooms. Few studies have considered the user experience of the technology, and none of the studies that have included data from human participants have been carried out in a real-world research setting over a long-term period. Thus, there is a general lack of understanding regarding the performance and suitability of EC glazing in real-world working environments. To address this gap in research, a new study of EC glazing was undertaken, looking at the experience of occupants working in an office that had been retrofitted with EC-glazed windows. The retrofit was the first of its kind in the UK, and provided an opportunity to study the user experience of EC glazing in a real-world setting over a longitudinal period. The aims of the study were to gain new insights into the experience of users of EC glazing, and to learn about the practicalities of installing it. A number of research questions were defined, leading to a mixed methods data collection programme, carried out over a period of almost 18 months. The data collection encompassed data from the occupants as well as from the physical environment, and was designed in response to the constraints of the site and occupants, as well as the aims of the research enquiry. The resulting data set includes a valuable record of occupant experiences and behaviour, as well as detailed information about environmental conditions at key times. A number of contextual factors influencing the effectiveness of EC glazing were identified. The outcomes of this research provide a new understanding of the user experience of EC glazing, and thus can inform further technological development and benefit future installations.
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