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The material authenticity of cultural heritage has been questioned by societies in which the modern paradigm of conservation has not developed from within the native culture. This paper examines the philosophical and practical traditions in Iran regarding the materiality and authenticity of past structures. By reviewing the emergence of the Western conservation paradigm in Iran, this paper highlights two key factors: the rapidness of this paradigm shift and the remarkable contradiction between the new and old paradigms. By borrowing the Deleuzo-Guattarian concept of a ‘body without organs’ (BwO), this paper problematises the rapidness and radicality of the paradigm shift in Iran. It suggests exploring the under-investigated possibilities between the pre-modern and modern paradigms to address the gap between native circumstances and Western standards.
In the time of increased awareness about the environment problems by the public opinion and also intensive international efforts to reduce emissions of greenhouse gases, as well increase of the generation of electrical energy to facilitate industrial growth, the conference offers broad contribution towards achieving the goals of diversification and sustainable development.
Focus of the student conference is to promote the discussion of views from scientists and students from Wroclaw University of Technology, Technical University of Ostrava and Brandenburg University of Technology Cottbus-Senftenberg.
The conference offers prominent academics and industrial practitioners from all over the world the forum for discussion about the future of electrical energy and environmental issues and presents a base for identifying directions for continuation of research.
The master thesis at hand examines the potential of district heating in Lusatia. The thesis follows the approach of first identifying technical and economic potentials in general and then transferring them to the study region. For the quantitative determination of district heating potential in Lusatia, the status quo is determined and a GIS-based analysis is carried out with regard to minimum heat demand densities. The extent to which district heating is suitable for climate-neutral heat supply will be investigated using the potential of renewable and waste heat energy sources. Furthermore, the regional economic effects of developing these potentials are examined. The results show that despite an overall decline in heat demand, there is potential to increase the relative share of district heating in Lusatia. In terms of climate neutrality, district heating in Lusatia offers special opportunities. Solar thermal energy and Power-to-Heat are of particular importance due to the rural character of Lusatia and its status as an energy region. From a regional economic perspective, climate-neutral district heating has a positive effect on value added and employment.
Sub-Saharan African cultural landscapes are adversely impacted by various development pressures, which calls for a holistic and integrated approach in their management. Mining development has been ranked highly by UNESCO World Heritage Centre, as one of the most common factors threatening the conservation and management of World Heritage properties around the world. For instance, out of 141 World Heritage properties which submitted their state of conservation reports in 2015, 18% were affected by mining activities. Out of these, 84% of the properties that were threatened by mining development were either cultural landscapes, natural properties and or mixed properties. African World Heritage cultural landscapes are the ones highly affected and threatened by planned and on-going mining and exploration activities.
Therefore, research was carried out using the Mulanje Mountain Cultural Landscape of Malawi and Mapungubwe Cultural landscape of South Africa. Specifically, the study aimed at examining the existing cultural landscape management theories and concepts in order to understand the key elements to be integrated into the suggested strategic management planning methodological framework. It also aimed at evaluating the impact of mining development on the conservation and management of African cultural landscapes. The study also investigated the stakeholder’s views and perception about the impact of mining activities on cultural and natural heritage values of the landscapes.
To achieve the research objectives, the literature was reviewed, firstly to determine the dimensions of cultural landscapes, and secondly, to determine the dimensions of mining development in World Heritage cultural landscapes. The study used two case studies as an effective comparative research strategy in the investigation of the conflicting issues of mining development against the conservation of the attributes of the two cultural landscapes. A case study research strategy was combined with other research methodologies. These included interviews, focus-group-discussions, observations, field site surveys, qualitative content analysis, and thematic analysis.
The study has revealed that stakeholder participation and inclusion is a key element in the integration of mining development in cultural landscape planning. This research has contributed to the methodological gap in cultural landscape management planning by developing and applying an integrated strategic management planning methodological framework. The application of this framework has shown that the governance in place for Mulanje Mountain cultural landscape conformed to the requirements of a long-term and holistic planning process and the participation and empowerment of multiple stakeholders in that process.
Architectural conservation is conventionally associated with preservation of buildings or ensembles that were seats of religious or secular power marking great architectural, political, or scientific accomplishments.
Dark and difficult heritage concerns events of disasters, extermination, and war. But what happens to stories and their places that do not fit into any of these categories? They are neither grand or beautiful, nor explicitly traumatic but nonetheless they embed cultural values and norms, or perhaps even the opposite of them: the bordellos and the marginalised groups of society that are usually disregarded in heritage discourses.
The question of sex work in contemporary culture holds an important place, as it is connected to social and economic rights of women. Historic sex work, and the places associated with it, imbed in this sense a contention value, because still today it provokes debate among different interest groups.
This research work presents the first in-depth study into the location of Florentine bordellos and sex workers between 1860 and 1888. It was a central moment in the history of these women and their trade because a new regulation on sex work was introduced by the recently unified Italian state which spatially controlled the sex trade. Each bordello and the sex workers came under intense scrutiny of the law. What was a dramatic development in the life of these women at the time, has allowed for extensive historical analysis.
The research draws primarily from over 5,000 archived police files and examines the location of sex trade in relation to the legal framework provided by the regulation known as the Regolamento Cavour. It was to ensure that sex workers would not pass on any venereal disease, while, at the same time, strived to maintain moral order in a continuously growing city, faced with urban development. In addition, the historic spatial development of bordellos within the perimeter of the ancient city walls was studied as well as the economic and political factors which influenced the position of a bordello within the urban fabric. For that purpose, the study incorporated information from historic city and street directories as well as cadastre maps. These different layers of information are conveyed in numerous maps to visualise the spatial context of and relation between sex work and spaces.
The powder metallurgically produced beta titanium alloys (traditional PM beta Ti-alloys) have long been plagued by high impurities contamination. For binder-based powder technologies, they originate from the sintering atmosphere, the debinding processes and the starting powders. In general, a normal carbon residual of binder-based powder technologies is capable of incurring the formation of aligned TiCx particles along beta grain boundaries (GB-TiCx) in most classes of beta Ti-alloys. Whereas, oxygen atoms are likely to deteriorate the ductility of PM Ti alloys by promoting the formation of diverse brittle phases and/or altering the deformation modes. Such materials exhibiting rather low toughness to strain ratios are not an option for critical structural applications, where catastrophic damage is completely unacceptable.
In this study, biotolerant metastable beta Ti-20Nb-10Zr alloys, containing a certain amount of carbon, oxygen residuals originated from materials processing and consequently 0.5 vol.% in situ synthesized TiCx particles, were fabricated via metal-injection-molding (MIM). With varying yttrium (Y) addition, the effects of Y-induced oxygen scavenging, beta-grain refinement and porosity increment on tensile properties were systematically investigated. To scavenge oxygen from the beta Ti-matrix, the Y elemental powder with a maximum particle size of 15 µm (e.g. <12 µm or 1200 mesh) is more appropriate than the commonly used <45 µm (i.e. 325 mesh) sized powder or larger ones and without significant detrimental effect on the as-sintered density of beta Ti-alloys.
A novel toughening strategy was proposed by regulating TiCx precipitation evolution and resultantly adjusting particles distribution pattern. Synchrotron radiation identified that two separate TiCx precipitation-type reactions occurred at the beta phase region and the alpha/beta region. In a narrow temperature range between these two precipitation reactions, dissolution of carbides was observed just below alpha/beta transus. Y addition can postpone TiCx precipitation. On the basis of those mechanisms, adjusting TiCx particle distribution was proposed for the first time, specifically a combination of yttrium addition (Y) and carbide spheroidization reprecipitation annealing (CSRA). As a result, aligned GB-TiCx particles were adjusted to dispersed intragranular TiCx particles. An apparent toughening effect (≈ 113% increment reaching elongation = 8.3%) was achieved after TiCx redistribution, while non-optimally aligned TiCx pattern seriously limited tensile toughness of materials. Here, the mechanisms of TiCx redistribution behavior and its toughening are elucidated systematically.
Climate change, CO2 reduction, resource efficiency are only 3 current keywords that describe the current industrial-economic situation. In order to influence climate change effectively, the conversion of supply systems with technically usable forms of energy must succeed in the next decade. The international network founded in Baku in 2015 bundles research activities in the broad field of energy supply and energy efficiency. Discuss current research approaches and results with scientists and experts from renowned universities and follow Azerbaijan's efforts to implement the energy revolution.
The increasing demand for competitive, whilst also environment-friendly airplane travel, compels the design of highly efficient engines in the aeronautical field. A potential for improvement of traditional polycrystalline Ni-based superalloys, aiming higher creep resistance, was investigated. The approach adopted the concept of metal matrix composites (MMCs) to incorporate a rigid discontinuous phase, in the form of particles, to a γ’-strengthened Ni-based superalloy. In order to make the concept feasible, different microstructures resulting from diverse manufacturing techniques were investigated. By using distinct mixing and sintering methods, powders of Inconel X-750 and TiC were combined to form composites containing 15 vol.% of reinforcing particles. Powders were prepared with low and high energy milling processes, and formed by uniaxial pressure sintering and spark plasma sintering methods. Non-reinforced variants and composites had microstructures thoroughly examined at their initial state and after long isothermal aging treatments. Selected variants were further submitted to tensile and compression creep tests at temperatures between 700 and 800 °C, in the stress range of 200 to 500 MPa.
A comprehensive analysis was conducted using techniques such as EBSD, XRD Rietveld refinement, EDS and TEM to evaluate the development of γ’, η and TiC phases, determining the achievable microstructures with each fabrication method and establishing their evolution after aging treatments over times up to 1000 h. Likewise, creep properties were analyzed by obtaining parameters such as creep exponents, threshold stresses and activation energies. A creep life estimation was conducted with the use of a Monkman-Grant relationship and a Larson-Miller parametrization. Lastly, the potential for a reduction in creep strain rates in a working turbine blade, considering the density of investigated materials as a parameter, was evaluated.
All produced composites presented power law creep, with dislocations surpassing γ’ particles by climb. The variant produced by high energy ball milling and spark plasma sintering exhibited the highest creep rates, resulting from intense diffusion through grain boundaries. It also presented η phase after long isothermal aging, which affects negatively the creep resistance. Contrastingly, in the variant produced by low mixing combined with pressure sintering the lowest creep rates were observed. It was proposed that reinforcing TiC particles effectively acted as a load bearing phase, counterbalancing the adverse effects of the intergranular diffusion in the refined microstructure. Furthermore, a higher microstructural stability was observed in this variant, resulting from limited interaction between TiC particles and the matrix during fabrication.
In this thesis we consider bilevel optimization problems in infinite-dimensional spaces. In particular, we are interested in providing first-order necessary optimality conditions. We consider bilevel optimization problems both in abstract Banach spaces and in some special situations. This includes the optimal control of the obstacle problem, which is a typical bilevel optimization problem in Sobolev spaces, as well as a class of inverse optimal control problems. We obtain optimality conditions for these more specific optimization problems by applying our results from the abstract setting.
Our main approach for deriving optimality conditions in the abstract setting utilizes the relaxation of a reformulation of the bilevel optimization problem via the optimal value function. We also introduce the so-called normal-cone-preserving operators and show how this concept can be applied.
We also consider other topics that arise in this context. For instance, we investigate the so-called limiting normal cone to a complementarity set in Sobolev spaces. This complementarity set plays a central role in the context of the optimal control of the obstacle problem. The limiting normal cone is a concept which appears in the area of variational analysis and generalizes the usual normal cone from convex analysis. We also investigate in which spaces Legendre forms and Legendre-* forms can exist. We show that if a Legendre-* form exists in a reflexive Banach space or a space with a separable predual space, then this space is already isomorphic to a Hilbert space. We also consider a discretization of a bilevel optimization problem in Lebesgue spaces. We present both theoretical error estimates and numerical experiments.
The new results in this thesis are illustrated by examples and counterexamples. In order to present the topics in a self-contained way, we review some known concepts and their basic properties. A particular focus for this is on the definitions and properties from the area of capacity theory.
The subject of this thesis is the development and test of silicon strip detectors for the high luminosity upgrade of the tracking detector of the ATLAS experiment at the Large Hadron Collider. Special emphasis is devoted to the understanding of the impact of mechanical stress on the electrical properties and the particle detection performance of detector modules.
First simulations were done to estimate the maximum expected stress on a sensor when operated at -30 °C within the future silicon strip tracking detector ITk, at ATLAS. The maximum stress in a worst case scenario is expected to be 27 MPa. Tensile strength tests were done to estimate the maximum stress which can be applied to a silicon strip sensor. Silicon shards, with a thickness and dopand concentration corresponding to the ITk sensor specifications break at >23 MPa, wafers at >700 MPa and sensors at ~ 400 MPa. The huge variations lead to the assumption, that the tensile stregth, which is highly dependent on the quality of the crystal lattice, is due to different cutting technology. Wafers, irradiated with a fluence equivalent of a lifetime dose of an ITk sensor, show no stress dependency of the youngs modulus. The tensile strength of irradiated wafers is decreased by ~ 6,6 %. No damage on silicon sensors from mechanical stress is expected for sensor modules installed it the ITk.
The electrical properties of silicon strip sensors were studied for applied mechanical stress on ATLAS07 sensors up to 60 MPa. The specifications of the sensors are similar to the specification of strip sensors in the future silicon strip tracker barrel region of the ATLAS detector. The leakage current changes at 50 MPa by -1.7 %, the bias resistance by +0.8 % and the interstrip resistance by -25 %. The depletion voltage and the implant resistance are not affected by mechanical stress. Except for the interstrip resistance the results can be explained by piezoresistive effects.
Silicon strip modules were build and studied in particle test beams. These modules consists of an ATLAS07 or an ATLAS12 sensor and an analogue readout to study the influence of stress on the module performance. The sensor module noise is independent from the applied stress. An effect of stress on the signal strength was seen. The ATLAS07 sensor module signal strength was decreased and the ATLAS12 sensor module signal strength was increased with a slope of ~0,6 MPa^-1. The average cluster size of the ATLAS07 sensor module was increased by 0,25 % MPa^-1 and the average cluster size of the ATLAS12 sensor module was decreased by 0,06 % MPa^-1 with applied stress.