500 Naturwissenschaften und Mathematik
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Die Einzelfadenverklebung zur Rissschließung in Leinwandbildträgern stellt ein bedeutendes Forschungsfeld dar, dem sich diese Arbeit widmet:
Erstmalig wurden in einem gemeinsamen Kontext uniaxiale Zugprüfungen an freien
Klebstofffilmen, verklebtem Garn und Gewebestreifen neben biaxialen Zugversuchen und multiaxialen Berstdruckprüfungen an Gewebeproben aus Leinen gegenübergestellt. Dazu wurden Rissverklebungen mit einer Auswahl unterschiedlicher Kunstharzdispersionen und Störleim-Modifikationen in überlappenden bzw. Stoß-auf-Stoß-Verbindungen mit und ohne Fadenbrücken angefertigt.
Ziel der Untersuchung war es, die einzelnen Einflussfaktoren bei den verschiedenen Versuchsreihen zu vergleichen und eine geeignete Prüfsystematik für die Klebstoffbewertung zur Rissbehandlung in textilen Bildträgern zu entwickeln.
Es zeigte sich, dass nur die Prüfung mehrerer verklebter Fäden im Gewebeverbund als langfristig sinnvoller Prüfaufbau verfolgt werden sollte. Im Zuge der Verklebungsbetrachtung konnten zudem vielversprechende Klebstoffe und -modifikationen gefunden sowie der zusätzlich verfestigende Effekt von Fadenbrücken an Stoß-auf-Stoß-Verbindungen belegt werden.
Intelligent use of energy is one of the keys to success for an energy revolution. To meet this challenge, smart meters are suitable tools because INTELLIGENT use of energy means not only to use efficiency technology, but also to determine load shifting potentials and use them accordingly. Especially farms with high power consumption are becoming increasingly concerned about reducing energy costs due to rising energy prices and need a systematic analysis of their operational energy flow. To find solutions for farms, the NaRoTec e.V., the TH Köln, and the Machinery Ring Höxter-Warburg have joined forces with partners and launched the project "Intelligent Energy in Agriculture", which is funded by the state of NRW in Germany. The aim of the project is to be able to give individual advice recommendations for energy optimization of agricultural holdings. This will be achieved inter alia through an operational energy audit and current measurements in different operating ranges. To achieve this, smart meters were installed in selected energy-intensive dairy and pig farms.
As part of the project, the installed smart meter information of one of the dairy Farms is used to optimize the energy consumption of the farm and increase the degree of self-sufficiency. A good way to achieve this is by taking a closer look at the cooling process of the produced milk since it is one of the most energy consuming processes on a dairy farm. In addition an installation of an ice cooling system instead of a direct cooling system enables the possibility to store self-produced energy in the form of ice and use it later on when it is needed to cool the milk. This flattens the usual energy peaks throughout the day and increases the degree of self-sufficiency. To ensure a sufficient amount of self-produced energy with solar power plants of various sizes were designed. The different sizes of the power plants are defined by the use of the gathered smart meter data is used to cover different electric loads in addition to the ice water cooling system. Afterwards the different simulated models are compared to find the best balance between energy production, investment cost and a high degree of self-sufficiency. First results show that using an ice cooling system in combination with a solar power plant improvement the degree of self-sufficiency by up to 7.8 %.
Intelligent use of energy is one of the keys to success for an energy revolution. To meet this challenge, smart meters are suitable tools because INTELLIGENT use of energy means not only to use efficiency technology, but also to determine load shifting potentials and use them accordingly. Especially farms with high power consumption are becoming increasingly concerned about reducing energy costs due to rising energy prices and need a systematic analysis of their operational energy flow. To find solutions for farms, the NaRoTec e.V., the TH Köln, and the Machinery Ring Höxter-Warburg have joined forces with partners and launched the project "Intelligent Energy in Agriculture", which is funded by the state of NRW. The aim of the project is to be able to give individual advice recommendations for energy optimization of agricultural holdings. This will be achieved inter alia through an operational energy audit and current measurements in different operating ranges. To achieve this, smart meters were installed in selected energy-intensive dairy and pig farms. As part of the project, the installed smart meter information about the consumption of various plants and their components were analyzed, regularities and adaptability in loading history identified, and the energy efficiency of the equipment and systems used verified (especially pumps, ventilators, feeding systems). Then recommendations were formulated to shift electricity-intensive processes to times with low electricity costs and high intrinsic power production. The resulting findings will be used as the basis for intelligent energy management in the further course of the project. Overall, efficiency streamlining measures in the field of ventilation and lighting systems, flexible dry feeding systems by decoupling power purchase and consumption, as well as energy savings and related CO2 savings were determined.
Die Dokumentation und Untersuchung von Massenbewegungen ist der entscheidende Schritt, um die Gefahr, die von ihnen ausgeht, zu identifizieren und im nächsten Schritt zu minimieren. Vor allem in Bergregionen kann dies im Extremfall Menschenleben retten.
Folglich untersucht diese Arbeit auf Grund bestehender Gefahr die räumliche Verteilung von Massenbewegungen in den drei iranischen Provinzen Alborz, Qazvin und Teheran.
In Anbetracht der immer weiter wachsenden Städte im erdbeben- und somit massenbewegungsgefährdeten Elbursgebirge wird mittels zweier quantitativer Analysen der isolierte Einfluss von straßen- und schienengebundener Verkehrsinfrastruktur auf Massenbewegungen (in den drei Provinzen) untersucht.
Beide Analysen vergleichen ausschließlich die lokale Häufung von Massenbewegungen mit dem vorhandenen Straßen- und Schienennetz: in der ersten Analyse durch das Vergleichen stattgefundener Massenbewegungen innerhalb von Teilgebieten des untersuchten Gebiets, in der zweiten Analyse werden die Häufungen in verschiedenen Abständen zu Straßen erfasst.
Anknüpfend an die zweite Analyse wird eine Bewertung der Häufigkeiten getätigt.
Es ergeben sich folgende wesentliche Erkenntnisse aus dieser Bachelorarbeit:
• Die Aussagekraft der Analysen kann höchstens so groß sein wie die Richtigkeit, Vollständigkeit und Detailliertheit der zur Verfügung gestellten Datenbanken
• Die verhältnismäßig große Fläche des Untersuchungsgebietes stellt eine hohe Fehlerquelle dar (z.B. durch das große Datenvolumen)
• Eine Anfälligkeitsanalyse auf Grund eines isoliert betrachteten Auslösefaktors ist mit vielen Fehlern und Annahmen behaftet (z.B. muss zunächst einmal angenommen werden, dass Massenbewegungen nicht durch andere Faktoren ausgelöst werden)
• Eine erhöhte Anfälligkeit des Untersuchungsgebietes gegenüber Massenbewegungen innerhalb von 50 m Abstand zu Straßen konnte durch die in dieser Arbeit beschriebenen „Straßenpufferanalyse“ nachgewiesen werden.
Die Analysen sind mit dem Programm ArcGIS durchgeführt. Ihre detaillierte Beschreibung ermöglicht es dem Leser, die Analysen weiterzuführen oder mit anderen Parametern zu wiederholen. Weiterführende Analysen beispielsweise in Form einer Risikokarte verhelfen den Menschen, Sachgüter und die Umwelt z.B. durch nachhaltige Bebauungspläne zu schützen.
Jordan is deemed as one of the least water-endowed regions in the world. The acute water shortage, accompanied with changing climatic conditions have necessitated the increasing use of treated wastewater (TWW), predominantly in irrigated agriculture sector. This is especially true with the upper Zarqa River. The ample supply of TWW resources can be found there; paradoxically, the practical implementation of TWW reuse is hindered by the enforcement of irrigation water quality standard, compounding pressure on the dwindling groundwater resources. In light of the large potential source of TWW, this study aims to supply knowledge on maximizing the safe reuse of TWW while minimizing the environmental impacts within the local environment of the upper Zarqa River. A SWOT analysis was conducted to identify the strengths, weaknesses, opportunities, and threats of TWW reuse for agriculture in the local context. In recognition of the projected growth in the treated effluent to more than 135 MCM in the coming ten years, and how it would affect the water use on the study region, several plausible development scenarios were proposed based on expected developments on the ground. Considering the vital role of TWW in sustaining multiple ecosystem services, this study addresses the need to review current standard, encourages managed aquifer recharge with TWW, recommends crops type modification, and enhances knowledge on suitable practices at farm level. Each of these factors is needed in order to deliver a range of ecosystem services to sustain the local rural communities and to advance them in the face of profound challenges, thereby leading to its stability and increased productivity.
Das Ziel der vorliegenden Masterthesis ist es, einen Überblick der verschiedenen Datenbanktypen und Leistungsanalysen zu geben. Die vergleichende Literaturstudie beschäftigt sich mit einem jungen Forschungsfeld und betrachtet insbesondere nichtrelationale NoSQL-Datenbanken, welche in den letzten Jahren immer beliebter geworden sind und einige Vorteile gegenüber relationalen Datenbanken aufweisen. Doch was können die konkreten Datenbankimplementierungen bei unterschiedliche Datenmodellen leisten und welcher Testaufbau bietet sich bei welchen Einsatzanforderungen an? Zu Anfang definiert diese Arbeit Kriterien zur Bewertung von Leistung und untersucht experimentelle Vorgehensweise verschiedener Forscher. Ein wichtiger Fokus liegt darauf, die Vergleichbarkeit der Messmethoden und Ergebnisse einzuschätzen und zu gewährleisten. Neben dem methodischen Vorgehen wird mit dem YCSB-Framework ein wichtiges Werkzeug besprochen, mit dem Leistungsmessungen in NoSQL-Datenbanken implementiert werden können.
Amboseli-Tsavo Ecosystem is a unique landscape in Kenya’s semi-arid rangelands to the border of Tanzania. It is characterized by high abundances of wildlife which frequently disperses between three National Parks, namely Amboseli, Tsavo West and Chyulu Hills. Due to an increased population and a land-use change from prior nomadic pastoralism to sedentary farming activities, the land became highly fragmented and transformed into a human-dominated area. Increasingly wildlife migration routes are becoming blocked, leading to isolation of the National Parks and multiplied human-wildlife conflicts. The African elephant (Loxodonta africana) is sadly famous as the most common conflict animal causing damage to properties, cropland and injuring or killing livestock and, in the worst case, people. However, elephants are at the same time a flagship species and represent the backbone for tourism activities around Amboseli. Therefore, the elephant is both a very valuable and problematic asset in the area. Unfortunately, wildlife conservation practices over the last decades, favoring animals over humans, have led to a negative perception of wildlife among the population in the ecosystem which challenges appropriate conservation mechanisms.
To maintain the tourism attraction of viewing elephants and to minimise the conflicts between local communities and animals, migration routes should remain open. The concept of landscape connectivity ensures biodiversity conservation, particularly for far-distance migration animals such as elephants. The elephant was therefore chosen as a keystone species in this study on which the analysis is based.
Using a least-cost path analysis (LCP) in ArcGIS, “cheapest” travel routes of Loxodonta africana between the three National Parks were identified. Factors included were selected and weighted by information gathered in expert interviews. Satellite imagery were classified using ESA SNAP toolbox to obtain vegetation covers and waterbodies for two different seasons (dry and wet), aiming to illustrate the temporal variability of potential connectivity paths. Additionally, key informant interviews and interviews of Group Ranch members around Amboseli National Park were conducted to gather information regarding the current state of management in the ecosystem and perceptions about wildlife management. A subsequent SWOT Analysis on three optimum routes obtained through LCP, takes the social-political factors and information obtained into account to discuss the different options for their conflict solving potential.
On the one hand, recommendations resulting from this study identify possible elephant migration routes that should be maintained by using a participatory conservation approach to secure landscape connectivity in long-term. On the other hand, management recommendations include a design for improved relationships between Group Ranch members and the responsible governmental institutions by equally distributing benefits, implementing financial benefits and establishing a functioning and adequate compensation scheme. By ensuring peoples’ active participation in conservation and wildlife management, a more positive attitude towards wildlife might be induced, which will positively influence the wildlife conflict in long run.
This thesis presents the perspective and basis for modeling of retail electricity price components in Germany. Detailed Python models are developed to provide predictions for yearly development of average network charges, EEG, StromNEV-19 and KWK surcharges for the period 2015-2035. For network charges and EEG surcharge, scenario-B (2035) from NEP2015 has been chosen as the model scenario. For KWK surcharge, the 2025 KWK share target, set by KWKG-2016, has been chosen as the model scenario. Individual component model results are validated against available academic literature and institutional reports. Model results for EEG surcharge, indicate an increasing yearly EEG costs till 2024, after which the expiring EEG plants of past will unburden the related high costs and EEG surcharge will drop but still be around 99% of 2015 level in 2035. Model results for network charges indicate a consistently increasing yearly trend owing to high grid investments needed for reaching the target RE share of 57%. KWK model results also indicate a growing KWK surcharge until 2020 which then would remain stagnant at that level onwards. All model results are collected under three consumption categories, namely, households, privileged and nonprivileged industries. The final results indicate that the average German household will face an overall increase of around 3.37 Cents/kWh in retail electricity prices (excluding VAT) till 2028, after which the retail prices will drop a little due to dropping EEG surcharge. The similar but slightly reduced trend can be seen for nonprivileged industrial consumption. The increment effect, however, is only minute for privileged industrial consumption due to high exemptions in EEG & KWK surcharges and reduced individual network charges.
For sustainable climate, an exponential growth in renewable heating and cooling is compulsory to reduce consumption of the fossil fuels for production of heat. An essential step from European Commission as an introduction of the strategy for renewable heat has
given a platform to the solar thermal market to tap the highest possible potential. To grab the opportunity given, capacity of the production is to be increased as well as reduction in cost of solar thermal product is to be achieved by any suitable alternate means. Polymer
based hybrid collector, named as OPVT collector, is the innovation from Fraunhofer Institute of Solar Energy Systems to break the road blocks for the solar thermal market. A polymer solar cell and a polymer solar thermal collector, both, technologies have tendency
of high initial investments and extremely low running cost in business. The aims of this study were to develop a calculation tool for determination of production cost of different OPVT collector concepts and evaluate their potential with reference to market size. The tool was expected to be uniform for all possible concepts of OPVT collector and flexible in
usage during the early stage of technological development. In this study, “Microsoft Excel” software based calculation tool is developed for estimation of production cost for different concepts. A Car washing station for water based OPVT collector and a bus station for air based OPVT collector are found be most suitable for start-up of the business. The analysis of results has highlighted that the minimum cost of OPVT collector can be referenced as its material cost. The OPVT collector business has huge potential and
possibility of early break-even point in the
production. As production costs are sensitive to
material costs, input values to the tool must be accurate. Presence of dominance of the material cost
is due to high cost of OPV. In industry, OPV is still being considered as the technological product instead the commodity product. This market potential study for
OPVT collector technology has been the important step in giving the confidence to solar thermal, polymer and plastic processing industries for business investment.
Keywords – OPVT collector, production cost, calculation tool, market size
In Sierra Leone, at the moment 10 out of the total 14 districts are faced with the problem of large-scale land investments for industrial agriculture (oil palm, sugarcane…). The production is mainly for the local, regional and world market. There are quite many of these investments in the planning stage, while some are extending their operations by taking more land from communities or are already at the production stage. Studies and media reports have claimed a number of negative impacts felt in communities hosting these companies, ranging from loss of land, food insecurity, increase in poverty to loss of livelihoods, environmental degradation as well as social and cultural problems. The goal of this thesis is to examine the impacts of the operations of “Socfin Agriculture Company” on food security of local communities in Malen Chiefdom, Pujehun District of Sierra Leone.
Both quantitative and qualitative research methods are used for data collection, analyses, and interpretation of results. The research uses household income and expenditure to compare household food security before and after the start of the company’s operations. It examines consequences of community’s loss of land to support household food production versus casual wage earn from employment created by the company to meet household food security.
The results show a loss of household’s income sources and a significant decrease in households’ income. Households’ food crop production has reduced accompanied by a complete loss of cash crop farming. Households affected by the operations of the company have lost access to land and other natural resources that support food production. Furthermore, the company employs very few people in comparison to the total population of affected communities. Calculation of total wage earn from employment by the company cannot meet the staple food (rice) needs of the households. Also, households claimed a host of unfilled promises made by the company and national government at the onset of the operations of the company.
In conclusion, household food production is the most significant determinant for household food security, with regards to food availability, accessibility, utilization and stability of supply. Therefore, national government should carefully study and develop a framework that addresses food security of households impacted by the operations of the rapidly growing large-scale land investment companies and ensure a fair share of the local community in the economic development of the country and suggesting ways of improving access rights in the context of tenure.