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Learning from the past, designing for the future : sustainability of the Mediterranean vernacular
(2020)
With climate change and the depleting ozone layer, awareness about protecting the environment is increasing and “Sustainable Architecture” is becoming an essential part of the architectural future of cities. However, sustainable buildings of today are being built with high cost, high tech systems which can be reduced by taking advantage of past technologies and systems. The brilliance of vernacular architecture and the way man adapted to his surroundings fascinated me and inspired me to do further research on the sustainable characteristics of vernacular settlements of the Mediterranean area in order to determine if these characteristics can be applied to present and future architecture in an innovative way to create sustainable buildings with least possible energy consumption.
The method of research was based upon a general analysis of the passive design (solar and wind) characteristics of a town or settlement in Mediterranean climate starting from its site elements such as topography, vegetation, water. After that its urban structure, such as the geometry, block and street orientation and dimensions. Following that, the dwelling characteristics like dwelling shape, orientation and dimensions and finally the thermal regulating elements found in these dwellings, such as windows and vegetation. These elements were given a score according to their contribution to energy savings in buildings. Four case studies were chosen: two vernacular case studies from the region of study (the Mediterranean Coasts) and two modern case studies inspired by the Mediterranean vernacular. The analysis was repeated in the same sequence mentioned: Site, Settlement, Dwelling, Element, for the actual performance of each case study. The elements were given a number of points out of the score assigned for each element in the general analysis.
A total score and rating for each case study resulted from this analysis. The objective of these scores were to compare the performance of the vernacular case studies to the vernacular inspired case studies in terms of energy savings. The final scores displayed comparable results between both types of case studies meaning that when these modern settlements were designed with an influence from the Mediterranean vernacular, their performance in energy savings was close to that of a vernacular settlement. That means that it is possible to design settlements which are influenced by vernacular settlements and can even defeat them by following the general guidelines of the vernacular passive design characteristics in addition to modern tools and innovative methods. These guidelines can be reflected in a handbook and rating system which can become a simple step by step guide for architects and planners to design sustainable settlements without the need for expensive and complicated rating systems and consultants.
This thesis is an attempt to assess some of the effects that electroquasistatic body forces exert on turbulent internally forced convective flows. In order to do that, a stochastic turbulence model is employed, namely, the One-Dimensional Turbulence (ODT) model.
The reduced dimensionality of ODT demands a reduction of the Navier-Stokes equations (and in this case, also the Maxwell equations), into a 1-D system. This is done by performing an asymptotic analysis in terms of the nondimensional numbers of the flow. Also, a validation step due to the relative novel character of the cylindrical ODT formulation is done for an incompressible and constant properties flow regime and a variable density flow regime. The validation is presented for both the temporal (T-ODT) and a novel spatial (S-ODT) formulation in both planar and cylindrical geometries. Results in the constant property case show that wall normal (and radial) profiles, in both the T-ODT and S-ODT formulations, show good agreement with each other and to the data of Direct Numerical Simulations (DNSs). For the evaluated variable density heated pipe flow, gradients at the wall can be better reproduced with S-ODT.
After validating the model, ODT is applied first into a planar configuration which emulates the flow in a wire-plate Electrostatic Precipitator (ESP). For this flow, the additional input energy due to the electroquasistatic body force has an effect on the modification of the bulk velocity, and subsequently, the skin friction coefficient. Some qualitative DNS trends are confirmed with ODT, such as the localized increase of the Reynolds stress, as a consequence of increased eddy activity close to the discharge electrodes. Next, the results of ODT simulations in a cylindrical wire-tube ESP are presented. Here, ODT results are compared to experimental results. ODT results for global integral quantities such as the streamwise pressure gradient and the Nusselt number enhancement ratio are able to match in a reasonable way the experimental results. The competing relevance between the EHD contribution to turbulence by momentum, and by affecting the temperature and density due to the Joule heating effect is also analyzed, showing the leading order relevance of the former one. Specifically for the Nusselt number results, the sensitivity of the EHD flow to transition effects is shown to be very significant.
This thesis may open the door to a vast new field of phenomena which can not only serve for the further validation of the ODT model against DNSs or experiments, but also for the real use of ODT in applications which are so far inaccessible for traditional DNSs.
The overall research goal of this doctoral thesis is to better understand the determinants of sustainable purchase behaviour. By approaching several context-specific subgoals in a series of four quantitative empirical studies, major research gaps in the field of sustainable consumption are addressed. The first article examines the market potential for social banking in Germany. By means of an experimental survey using adaptive conjoint analysis, a sample of 2896 German social banking customers and a population-representative sample of 641 German conventional banking customers are compiled. Logistic regression modelling reveals that social banking customers differ significantly from their conventional counterparts regarding several consumer characteristics. The results further indicate a large untapped market potential ranging between 10 and 26% of the German population in 2011. The second article investigates the phenomenon of the attitude-behaviour gap in the context of sustainable clothing. Based on survey data of 1085 female German consumers, a structural equation model is estimated to assess how large the possible gap between a positive attitude towards sustainable clothing and the corresponding purchase behaviour is. Apart from a considerable attitude-behaviour gap, the article indicates that a positive attitude, self-transcendence values, as well as an affinity to online and catalogue shopping, significantly enhance sustainable clothing purchases. Self-enhancement values and, remarkably, a preference for durability constitute purchase barriers. The third article studies the influence of product lifetime labelling by the example of electrical appliances. Using choice-based conjoint analysis, experimental survey data is collected from a population-representative sample of 499 German consumers. Hierarchical Bayes utility modelling suggests a decreasing positive effect of the label on purchase decisions and a deterioration of the purchase influence of existing brands. Structural equation modelling indicates, for instance, that the preference for a long product lifetime is fostered by a respective positive attitude and subjective norm. However, the attitude only exerts a significant influence if it is driven by personal rather than environmental gains. The fourth article sheds light on the effects of favourable and unfavourable environmental product information. The analysis draws on data gained from a survey-based experiment conducted among a population-representative sample of 524 German consumers. Using a two-level structural equation model, the results document that the negative effect caused by unfavourable product carbon footprint information on consumers’ willingness to pay is significantly stronger than the positive effect caused by respective favourable information. Furthermore, consumers tend to not substantially differentiate between different high-range degrees of positive or negative environmental information.
Due to the use of fossil fuel resources, many environmental problems have been increasingly growing. Thus, the recent research focuses on the use of environment friendly materials from sustainable feedstocks for future fuels, chemicals, fibers and polymers. Lignocellulosic biomass has become the raw material of choice for these new materials. Recently, the research has focused on using lignin as a substitute material in many industrial applications. The antiradical and antimicrobial activity of lignin and lignin-based films are both of great interest for applications such as food packaging additives. DPPH assay was used to determine the antioxidant activity of Kraft lignin compared to Organosolv lignins from different biomasses. The purification procedure of Kraft lignin showed that double-fold selective extraction is the most efficient confirmed by UV-Vis, FTIR, HSQC, 31PNMR, SEC, and XRD. The antioxidant capacity was discussed regarding the biomass source, pulping process, and degree of purification. Lignin obtained from industrial black liquor are compared with beech wood samples: Biomass source influences the DPPH inhibition (softwood > grass) and the TPC (softwood < grass). DPPH inhibition affected by the polarity of the extraction solvent. Following the trend: ethanol > diethylether > acetone. Reduced polydispersity has positive influence on the DPPH inhibition. Storage decreased the DPPH inhibition but increased the TPC values. The DPPH assay was also used to discuss the antiradical activity of HPMC/lignin and HPMC/lignin/chitosan films. In both binary (HPMC/lignin) and ternary (HPMC/lignin/chitosan) systems the 5% addition showed the highest activity and the highest addition had the lowest. Both scavenging activity and antimicrobial activity are dependent on the biomass source; Organosolv of softwood > Kraft of softwood > Organosolv of grass. Lignins and lignin-containing films showed high antimicrobial activities against Gram-positive and Gram-negative bacteria at 35 °C and at low temperatures (0-7 °C). Purification of Kraft lignin has a negative effect on the antimicrobial activity while storage has positive effect. The lignin leaching in the produced films affected the activity positively and the chitosan addition enhances the activity for both Gram-positive and Gram-negative bacteria. Testing the films against food spoilage bacteria that grow at low temperatures revealed the activity of the 30% addition on HPMC/L1 film against both B. thermosphacta and P. fluorescens while L5 was active only against B. thermosphacta. In HPMC/lignin/chitosan films, the 5% addition exhibited activity against both food spoilage bacteria.
Tattoo taboo : a reader
(2020)
In different parts of the world, tattoos historically have been expression of the socio-cultural identity of individuals or communities: Tattoos are firmly integrated into social practices as elements of initiation or marriage, in other parts of the world, however, tattoos carry negative associations being linked to immorality, and crime.
To research the practice of and places associated with tattooing a research-based study project was designed to address the practice of tattooing from the point of view of its cultural heritage values, both intangible and tangible. In the winter semester 2018/2019 this study project was offered jointly by the Chair of Architectural Conservation and the Department of Heritage Management at the Brandenburg University of Technology (BTU) Cottbus-Senftenberg. Twelve international students from the study programmes World Heritage Studies and Architecture participated in this study project, which included a field trip to London and Oxford and several interviews and interactions with researchers and academics from the fields of tattoo history, anthropology, medical sciences and museography.
A collection of students’ essays on this topic is presented in this reader with a particular focus on the tangible and intangible aspects of tattooing, and the spatial history of tattooing based on two distinct areas in London as a case study.
The papers are divided into three distinctive themes that are linked to the practice of tattooing. Section one is dedicated to tattoos as a form of heritage, the one to tattooing as a form of art, and the last one to mapping as a methodological tool to visualise, assess and present relationships between heritage, tattooing practice and its connection to the social fabric in London at the turn of the penultimate century.
The investigation of novel structure-to-property relations of many transition metal trihalides MX₃ by downscaling to promising monolayer is still pending. However, the production of two-dimensional MX₃ sheets that are both high crystalline and thin is an experimental challenge. This thesis is focused on the rational synthesis planning and the derived targeted preparation of thin MX₃ nanosheets (≤ 100 nm) on suitable substrates by chemical vapor transport (CVT) as well as their characterization by complementary analytical methods. CVT of nanosheets directly on substrates benefits of low timescales, less material consumption and only few structural distortions. For the determination of optimal growth conditions, the CVT processes of investigated compounds were initially simulated by using the Calphad method (program package TRAGMIN). Thus, the occurring transport efficient gas species and temperature dependent, dominating vapor transport equilibria were calculated to optimize the growth process in a direct and straightforward way. Based on prior simulation results single crystalline sheets of MCl₃ (M = Ru, Mo, Ti, Cr) and CrX₃ (X = I, Br, Cl) were successfully prepared at temperatures between 573 – 1023 K on YSZ (yttrium stabilized zirconia) or sapphire substrates. The adjustable CVT parameters (transport duration, temperatures or weighed starting material) were optimized with respect to the targeted synthesis of either bulk or nanosheets at substrates. Microsheets with thicknesses of less than 4 μm (α-TiCl₃) and about 20 nm thin nanosheets (α-RuCl₃, CrCl₃ and CrI₃) down to ultrathin flakes (≈ 3 nm, α-MoCl₃ and CrBr₃) were obtained by CVT. As a highlight, monolayers of α-RuCl₃ and CrCl₃ were isolated successfully by means of a subsequent delamination. The MX₃ sheets morphology and dimension was described by optical and electron microscopy, highlighting their two-dimensional nature. By several X-ray spectroscopy and diffraction techniques the desired composition (M:X = 1:3), high crystallinity and phase-purity of thick and thin MX₃ platelets was confirmed subsequently. With respect to MX₃ nanosheets a slight increase (α-RuCl₃, α-MoCl₃ and CrBr₃) or decrease (CrCl₃) in phonon energies was observed in comparison to their bulk counterparts. The magnetic properties of CrCl₃ micro- and nanosheets were determined to be solely ferromagnetic and thus different than those of the bulk samples. Finally, the structure-to-property relations were investigated at a first example. The catalytic properties of α-TiCl₃ microsheets were investigated by gas-phase polymerization of ethylene. By downscaling the catalysts thickness by CVT, we obtained an activity improvement of 24 % in comparison to bulk α-TiCl₃.
Anthropogenic threat for the world’s environment and ecosystems and financial constraints necessitate a wise use of resources for the implementation of biodiversity conservation measures. A cost-effective planning and governance of biodiversity conservation has to be done to achieve maximal ecological outcomes with given financial resources. A better understanding of available modes of governance can help to improve the cost-effectiveness of biodiversity conservation planning and implementation.
This thesis investigates the influence of governance mode choice on the cost-effectiveness for biodiversity conservation measure implementation in selected conceptual and empirical settings, and identifies ecological, economic and climatic factors of influence. Linking the cost-effectiveness analysis for biodiversity conservation measures to the make-or-buy decision enables a novel perspective on cost-effective biodiversity conservation. In this context, conservation agencies are assumed to have two main options to implement biodiversity conservation measures in principle: (1) the buy alternative in which land is purchased for the purpose of biodiversity conservation measure implementation, and (2) the compensation alternative where a conservation agency compensates landowner’s opportunity costs to incentivise voluntary conservation measure implementation by landowners.
Two conceptual ecological-economic models were developed to analyse the cost-effective governance mode choice and their sensitivity to changing ecological, economic and climatic parameters. Two empirical case studies were conducted to address the question of cost-effective governance mode choice for a conservation project in Schleswig-Holstein (Germany) and a federal state wide comparison of conservation activities in California (USA).
It was found that the buy alternative is more cost-effective than the compensation alternative if conservation budgets and interest are high. In addition, not only the choice of governance mode is relevant with respect to cost-effectiveness, but also the mechanism to spatially select conservation sites chosen within a selected governance mode. Changing climate change speed – among other factors – influences the cost-effectiveness of governance modes and site selection strategies. The cost-effective governance mode choice also crucially depends on the intended timeframe of a conservation project. For shorter timeframes, compensating landowners is the cost-effective governance mode, however for longer durations the buy alternative becomes more cost-effective. This effect arises specifically due high one-off costs for buying land, which however amortize over time, compared to high recurring costs for compensating landowners. Based on these findings, the policy recommendations are provided which aim to improve the cost-effectiveness of governance modes available for biodiversity conservation.
The European Parliament and Council has defined a mandatory specific emission target of 95 g CO2/km by 2020 for passenger cars. Vehicle weight is a significant factor contributing to fuel consumption. Reducing the weight of the vehicle can be one promising option for decreasing CO2 emissions, which becomes a top priority for the automotive industry. In this research, two approaches were used to address the need. One involved developing structural parts using fibre reinforced plastics (FRP), and the other involved designing and developing FRP–metal hybrid laminates, which were constructed by reinforcing FRP locally to the metal surface. Existing joining techniques such as riveting, bolting, adhesive joining, ultrasonic welding, and flow drill joining techniques require additional processing steps to perform the joining, which could considerably increase processing time, cost, and energy expenditure. The present work describes a method to join FRP and metals using the adhesion strength of the investigated polymers. The developed FRP–metal hybrid laminates combine the advantages of metal and FRP together. Steel hot-stamping is known to yield very high strength. Fibre reinforced plastic–metal hybrid laminates were developed using hot stamped steels to transfer their superior mechanical properties to the final structure. To utilize the complete lightweight potential of thermoset and thermoplastic polymers, FRPs and FRP–metal hybrid laminates were developed using both the polymers. Along with this increased demand for FRP structures, there is growing interest in a repair technique in the automotive industry. The second objective of this thesis consists of designing and developing a new repair technique, which regains the strength and stiffness properties of the damaged part. The existing scarf repair technique is not suitable for thin laminates, which have limited access to the damaged area. Perforation damages were introduced into the FRP structures using a low-velocity impact load. A modified injection repair technique is used to repair these damaged FRP structures. Non-destructive techniques were utilized to understand the damage and the effectiveness of the repair.
In the last 30 years, communication became one of the most important pillars of our civilization. Every day terabytes of information are moved wired and wireless between computers. In order to transport this amount of data, researchers and industry increase the data rates of the underlying communication networks with impressive speed. However, such ultra-high data rates are unavailable at the communication endpoints.
One reason why ultra-high data rates are still not available for the communication endpoints is their inability to handle the protocol processing at this data rate. In order to enable communication endpoints to process high-volume data streams, the protocol processing has to be parallelized and optimized on all processing levels. However, parallelization and optimization are cumbersome tasks, which are further complicated as the protocol processing is traditionally carried out by the operating system.
This thesis aims at circumventing these problems by moving the protocol processing into external processing hardware and interpreting communication protocols as stream processing problems. In order to achieve ultra-high data rates at the communication endpoints, a protocol stream processing design approach was developed and evaluated. The design process is separated into implementation, soft real-time analysis, parallelization, and mapping steps, which allow a scalable protocol implementation without paradigm changes. Furthermore, a data link protocol for 100 Gbit/s wireless was developed and implemented with the new stream processing design concept, in order to show its feasibility. The data link protocol is configurable for different communication conditions and easy to parallelize by providing different granularities of packets. The proposed design-process has shown to be suitable for uncovering bottlenecks and helping with debugging the individual stages of the protocol.
This thesis deals with a novel approach for analyzing and computing interior transmission eigenvalues of (piecewise) homogeneous media in two dimensions. It is based on approximating boundary data of respective eigenfunctions by the method of fundamental solutions. However, since a straightforward implementation would solely exploit ill-conditioned matrices and thus evoke spurious results, a stabilization scheme is incorporated. The combined method is then studied with a distinction between isotropic and anisotropic materials, and complemented by novel approximation theory each. Numerical validations complete the investigations for different wave type scenarios