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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.
81

Post-war reconstruction and development: a collective case study

Heleta, Savo January 2013 (has links)
Since the end of the Cold War, there has been a surge in post-war stabilisation, reconstruction and development operations around the world. Externally driven efforts have been shaped by the liberal peace framework, which assumes that a rapid transmission or imposition of neo-liberal norms and values, combined with Western-style governance institutions, would create conditions for lasting peace and prosperity. Only in a few instances countries have attempted internally driven post-war reconstruction and development; in most cases, these efforts were either ignored or suppressed by international analysts, experts, academics and organisations. Despite all the expertise and funding spent since the early 1990s, externally driven operations have not led to lasting peace and stability, establishment of functioning institutions, eradication of poverty, livelihood improvements and economic reconstruction and development in war-torn countries. All too often, programmes, policies and „solutions‟ were designed and imposed by external actors either because they worked elsewhere or because they were influenced by geopolitical, economic and/or security interests of powerful countries. Furthermore, external actors have tended to assume that generic approaches based on the liberal peace framework can work in all places, while ignoring local actors, contexts and knowledge. Focusing on Bosnia and Herzegovina, South Sudan and Somaliland, this exploratory qualitative study critically explores and assesses both externally and internally driven post-war reconstruction and development practices and operations in order to understand the strengths and shortcomings of both approaches and offer recommendations for future improvements. This is important since socio-economic recovery and economic development are crucial for lasting stability and peace in post-war countries.
82

Study of building code and calculation of energy consumption for same building situated in two climates, Chengdu and Stockholm

zhang, shan January 2015 (has links)
This report is aim to compared building standard of Chengdu city and Stockholm, as well as find out the suitable energy-saving scenario for two places. To simulate the total energy consumption of logistics building, energy software named design builder will be introduce to calculate. Some of other analysis will be implemented at the same time, including economic analysis, environment analysis and thermal comfort analysis.
83

Plastics as structural materials in building

Haghbin, Mahtab. January 1974 (has links)
No description available.
84

What can the site give to the building and the building to the site?

Robson, William M. 24 March 2003 (has links)
This thesis explores the relationship between the "constructed" (built) environment and the natural environment. What defines such a relationship and can the relationship be formulated? Surely a successful union is much like a marriage whereby one part is better than either of the individual parts. This thesis is an exploration into that relationship. It explores the nature of the built environment through the construction in the natural environment. In addition, it explores the possibility of utilizing a set of guidelines to assist the designer in the creation of such a relationship. The project type (Retreat Center) itself opens the door to possibilities by carving out the natural environment. It proposes that through careful design considerations a harmony can exist between man's built environs and the earth's natural environment. / Master of Architecture
85

Building research capacity at CUT (professional growth and development)

Selaledi, D. January 2009 (has links)
Published Article / This paper intends to argue that there are two inherent challenges and dilemmas that may incapacitate rising calls to develop a distinguished cohort of researchers at universities, including CUT. Firstly, it seems the episteme knowledge-base in research of the current cohort of staff members does invite a look in askance as to its depth and breadth. Do we sufficiently exude competence to develop budding researchers of note? Secondly, and deducing from my informal interviews and discussions with B.Ed Honours students since 2006; we somewhat fall short as lecturers to model the quintessential research expertise necessary to develop the students' phronetic research experiences - the success of which would reconcile with their practical reality in their diverse teaching and learning situations and circumstances. How then do we build a research capacity that catapults us from this somewhat research doldrums in the School of Teacher Education at CUT to become a School of Teacher Education recognised nationally and internationally as a School of Teacher Education which is enveloped in the validity and reliability of generating quality research? This paper explores various "givens' and "intellectual needs." And, quite academically, may rumble about conceptual and perceptual impediments and hurdles which under-gird the laborious exercise of undertaking research; though fulfilling to academic autarkical pride when done excellently.
86

En jämförelse mellan mineralull och cellulosafiber : Hur valet påverkar energianvändning, miljö, arbetsmiljö, kostnad och tidsanvändning

Pettersson, Frida January 2010 (has links)
No description available.
87

Zonindelning på grund av temperaturrörelser : Bandtäckning med färgbelagd plåt

Jonsson, Jonas January 2011 (has links)
Byggnadsplåtslagare ställs ofta inför problemet att själva få utföra en zonindelning på tak när de ska montera bandplåt. Detta trots att de saknar rätt kunskaper och att det inte finns någon komplett arbetsbeskrivning att tillgå. Zonindelningen utförs på grund av temperaturrörelser i bandplåten. Examensarbetet ska undersöka på vilket sätt zonindelningen bör utföras i Karlstad. Resultat ska kunna användas som underlag när byggnadsplåtslagare ska indela taket i zoner. Arbetet avgränsar sig till bandtäckning utförd i lackad varmförzinkad stålplåt.   Arbetet ledde fram till ett resultat som kan användas för att lägesplacera den fasta zonen. Placeringen utgår från taklutningen och på hur bandplåten sammankopplas med detaljer vid takfoten eller språnget.  Fasta klammer ska endast användas i fasta zonen och glidklammer på övriga ytor. Beroende på utförande vid anslutningar till bandplåten kan rörelser hindras eller möjliggöras. De flesta hinder och genomföringar kan utformas så att de inte hindrar bandplåtens rörelser. Rörelsemånen som behövs kring hinder och genomföringar beräknades. Det finns detaljer som kan hindra rörelser bl.a. fotränna och vinkelränna. Men i en del fall kan det finnas alternativa lösningar på anslutningar som tillåter rörelser och även beaktar kravet på täthet.   Enligt beräkningar kan plåtens temperatur uppgå till + 76° C under sommaren och -36° C på vintern. Bandplåtens längd ökar när den blir varmare och minskar när den blir kallare. Temperaturen då bandplåten monteras avgör hur längden kommer att förändras från sin ursprungliga längd när det blir varmare eller kallare. Den maximala bandlängden är 15 m från centrum av den fasta zonen. Den bestäms av temperaturrörelserna och möjligheterna att ta upp dessa rörelser.
88

Processing and characterisation of cementitious materials reinforced with fibres

Khalifa, Abdalla January 2015 (has links)
Presented in this thesis are the test results of combined processing and mechanical property characterisation studies using a developed cementitious mix reinforced by various fibre types and forms (with short and continuous lengths). The research is aimed to identify new Fibre Reinforced Cementitious (FRC) composites that have post-cracking ductility, much higher flexural strength and higher toughness than the control (matrix) material without reinforcement, and higher than traditional FRC composites. Laboratory work uses two methods to process the green forms, one by novel compression moulding and the other by hand lay-up that were both adapted from the fibre reinforced polymer industry. Results show a reduction in the hand lay-up water/binder ratio of 24 to 41% can be achieved by applying compression moulding with a pressure of 9MPa. One key processing challenge with short recycled milled carbon fibres is to make the mix uniform, even when the volume fraction is low at 2%. Microstructural investigations confirm that the carbon fibres, having mean length of 0.085 mm, always gave a very poor dispersion, and this is due to static electricity causing the fibres to form into balls (5 to 30 mm diameter). Overall, the study with short fibre reinforcements found that, by adding 2% by volume of the polyvinyl alcohol (PVA) fibres, the stress-strain curve exhibits strain-hardening behaviour accompanied by multiple cracking. Furthermore, the flexural properties show the material to possess ductility, toughness and mean strength that, at 13 MPa, is two times higher than the control material. It is observed that the hydrophilic nature of PVA and the fibres surface roughness play a significant role in an increased bonding strength with this short fibre. When introducing continuous fibre reinforcement in the form of fabrics it is shown that the volume fraction of fibres should be no more than 5%. Unsuccessful green form specimens were a consequence of having a higher volume fraction by introducing more fabric layers. Test results show that materials reinforced with carbon fabrics give an FRC material with much improved mechanical properties, in terms of post-cracking strength, strain at peak stress and toughness (energy absorption) at peak stress. Higher overall bond strength might be attributed to an apparent increase in interfacial contact area between fibres and cement matrix and improved mechanical anchoring from the fabric’s construction. Microstructural investigations confirm that good matrix penetrability between the filaments of the tow or bundle is essential in order to maximise the reinforcing efficiency of the fabric. Investigated are two novel methods for modifying the continuous unidirectional carbon fibre reinforcements to improve the overall bond strength, by enhancing matrix penetration through and across the reinforcement plane. In one method the fabric is cut into strips to leave spaces (holes) between parallel reinforcement units for the matrix material to bridge across, while in the second method the fabric receives a surface treatment by immersion in Ethanol alcohol. Test results show that, with compression moulding and the strip form of reinforcement at 5% volume fraction the FRC composite has a flexural strength of 75 MPa. This flexural strength is ten times higher than the measured strength of the control material. The experimental research reported in this thesis shows that to achieve ‘unusual’ composite action and a relative high stress at loss of proportionality requires a continuous fibre reinforcement that can be treated or non-treated. Given the considerable increase in mechanical properties achieved using such fibre reinforcement at 5% the most promising FRC materials require to be further evaluated to find suitable candidates for load bearing products.
89

The performance and properties of novel desiccant coated heat exchange surfaces for solar air conditioning

Spillmann, Thorsten S. January 2014 (has links)
This work deals with the preparation, thermo-hydraulic characterisation, and performance analysis of silica gel coated highly conductive surface enhancing structures to be used as tube inserts in a prototype of an innovative water-cooled sorption rotor. The candidate inserts under investigation comprise highly porous aluminium foam inserts, twisted-in wire brushes, and flocked structures, that are investigated for their flow impedance, heat transfer performance, and cyclic dehumidification performance. The conducted analysis comprises experimental testing of insert specific pressure drop and heat transfer performance in a purpose built test rig, that led to the preselection of the foam structures and a twisted-in aluminium wire brush insert for desiccant coating and further investigation. Cyclic heat and mass transfer tests were performed in a purpose-built small-scale test rig, that simulated the dehumidification process of a desiccant rotor with and without employing water-cooling. The experimental analysis is complemented by a numerical investigation of the cyclic heat and mass transfer performance of the brush and metal foam type structures, modelled as two-dimensionally axis-symmetric porous media. The geometry based functions of the insert specific flow characteristics are derived from two- and three-dimensional pore scale computational fluid dynamics models, that are calibrated against experimental data. The validity of fundamental modelling assumptions was confirmed by a decent agreement between numerical and experimental steady-state heat transfer results. The heat and mass transfer investigation showed that the investigated structures were capable of effectively removing heat during the dehumidification half-cycle. The thermal mass was shown to be a critical design parameter in achieving acceptable dehumidification performance.
90

Shear transfer in cracked reinforced concrete

Millard, S. G. January 1983 (has links)
The objectivc of this research was to determine the in-plane shear stiffness and strength of a reinforced concrete sprecimen, which had first been cracked in uniaxial tension. This information could then lead to a more accurate analysis or reinforced concrete structures using the finite clement method. Tests were devised that enabled the effects of aggregate interlock and of dowel action in slab type specimens to be studied independently. As the aggregate interlock and dowel action specimens were similar and were loaded in the same way, a direct comparison of the test results could be made. The composite effects of aggregate interlock and dowel action were then studied by applying the same shear loading to cracked reinforced concrete specimens. The shear stiffness and strength due to aggregate interlock were typically found to be two to four times as great as those due to dowel action. It was also observed that the crack in the aggregate interlock tests tended to widen as shear slip occurred. This is an effect which has received very little attention in the past. The stiffness normal to the crack that restrains crack widening, and the initial crack width were both observed to have a significant influcnce on the aggregate interlock shear stiffness. The behaviour of the reinforced concrete specimens was similar to that which was expected from the results of the dowel action and aggregate interlock tests, if the additional effects of local bond were LikclI into consideration. Several analytical models of the micro mechanisms of shear resistance within the specimens were studied and formulae were derived to predict their behaviour. A matrix equation for the material properties for cracked concrete was derived and used in a finite clement analysis in an attempt to model the behaviour of a reinforced concrete structure.

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