Research question | EPFL Graph Search

A research question is "a question that a research project sets out to answer". Choosing a research question is an essential element of both quantitative and qualitative research. Investigation will require data collection and analysis, and the methodology for this will vary widely. Good research questions seek to improve knowledge on an important topic, and are usually narrow and specific. To form a research question, one must determine what type of study will be conducted such as a qualitative, quantitative, or mixed study. Additional factors, such as project funding, may not only affect the research question itself but also when and how it is formed during the research process. Literature suggests several variations on criteria selection for constructing a research question, such as the FINER or PICOT methods. Definition The answer to a research question will help address a research problem or question. Specifying a research question, "the central issu

Impact of Insurance on Earthquake Risk Territories in Japan

Rémy Zgraggen

The subject of the present PhD thesis is the qualitative, interdisciplinary analysis of the impact of earthquake insurance on earthquake risk territories in Japan. On the one hand, the Japanese Earthquake Insurance System (JEI) will be analyzed; on the other hand, the liability insurance system for nuclear risks in Japan will be examined. The first research question (R1) focuses on the impact of insurance on earthquake risk territories, whereas the second research question (R2) concerns the adequacy and efficiency of earthquake insurance and the nuclear liability insurance system in Japan. These two research questions will be analyzed in the following two case studies: the Great Hanshin Earthquake in 1995 in the Kobe-Osaka area, and the Tohoku Earthquake, including the following nuclear disaster at Fukushima, in 2011 in the northern part of Japan. In the first case study, the functioning and influence of the JEI will be examined, whereas in the second case study, the liability insurance system for nuclear risks in Japan will be analyzed.

EPFL2015

A Combined Energy-Economic Optimization of the Location and Installation of Photovoltaic Panels

Nicolas Elie Abdelhak, Thibaut Montbarbon, Maxime Pierre Gabriel Thivolle

This project is an exploration of a research question in the environmental and economic domains. This project’s intent is to explore a multi-objective optimization of the placement and installation of solar panels by analyzing the quantum of their energy production and the economic value of this energy for the grid. This is an idea that has received a considerable amount of attention in the literature. We build on this research by widening the scope of previous studies and incorporating other factors such as the stochastic aspects of weather and performance, price dynamics, terrain and urban influence, among others. In this report we do some observations about different parameters that have an influence on the production of the panel first and then on the economic part. The work focus on the following parameters: - The orientation of the panel in terms of tilt (vertical angle from horizontal position) and orientation (horizontal angle from North) obviously has a critical influence of the amount of production; what will be the optimal angles such that the production is optimized? - The location may have an influence on the production but in witch way; does close location in term of weather will produce at the same efficiency? - The technology may have a small impact on the production; what will be the main difference between a given technology and another? - The set-up of the panel will change the production as well and it is said to be really relevant in term of production; what will be the difference between a panel close to the roof to another free standing and ventilated? After having analyzed all those parameters in term of production, we investigate the relevance of our observations in term of financial yield. In order to answer those questions, we proceed with the approach: 1. Description of the technical aspects of energy production of a PV panel submitted to solar radiation a. Calculation of the raw irradiance on a tilted plane b. Calculation of panel efficiency itself for some given situations 6 EPFL 2. Description of the economic aspects of energy production and pricing 3. Optimization of the PV panel production through optimization of Tilt and Orientation angles 4. Optimization of the PV panel financial yield through the study of the effective cost of the installation for different economic scenarios. 5. Presentation analysis of the results and discussion

2013

Mechanical Activation of Chemical Bonds at Polymer Interfaces

Julian Nicolas Bleich

Polymer brushes are a specific class of polymer thin films in which each chain is tethered to the underlying substrate via one chain end. In sufficiently densely grafted assemblies, the individual polymer chains are forced into an extended chain conformation and form a brush-like structure, colloquially referred to as polymer brush. Upon incubation in a good solvent, polymer brushes experience swelling which leads to a tension at the polymer brush - substrate interface. This tension is believed to mechanically facilitate cleaving reactions at the tethering point resulting in the detachment of polymer chains, a process which is known as degrafting. Degrafting, and in the case of crosslinked polymer brushes delamination, has been reported for a large variety of polymer brushes and surface materials. Even though this phenomenon is already known for more than two decades, in depth understanding of the underlying mechanism is lacking and quantitative description of the process is rare. This thesis aims to gain further understanding of the phenomenon by quantitative description of the degrafting process. Further, swelling induced mechanical activation at the tethering point of the polymer to the underlying substrate is discussed in the context of polymer mechanochemistry and presented as a tool to selectively facilitate mechanophore cleavage at the interface. Chapter 1 provides a short historical review on the development of polymer mechanochemistry and gives an overview of commonly applied techniques in the field. The concept of polymer mechanochemistry is then extended to polymer brushes and the discussion results in a number of issues and research questions which are addressed in the subsequent chapters. The preparation and characterization of polymer brushes is not trivial. In Chapter 2 limitations and challenges with focus on experimental reproducibility and thin film characterization are discussed. Chapter 3 discusses the influence of a number of factors, i.e. grafting density and molecular weight of the polymer brush, solvent quality and salt concentration in the incubation medium, on the degrafting process of hydrophilic brushes in aqueous media. Further, the degrafting behavior of polymer brushes prepared from different monomers is compared. It is attempted to correlate degrafting behavior with polymer brush swelling. Contradicting results concerning the actual cleaving point of chains in polymer brushes are found in literature. In Chapter 4 presents structures incorporating only one single potential cleaving point. However, non-specific degrafting could not completely be suppressed. Further, a disulfide bond and oxy-norbornene moiety, commonly used mechanophores, were introduced at the anchoring point. In Chapter 5 the limitation of unwanted background hydrolysis was circumvented by investigating degrafting processes in dry organic media. Specific cleavage of the two mechanophores, disulfide and oxy-norbornene, could be demonstrated.