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Working women have more compulsive buying tendencies which can lead to a significant increase in their household consumption expenditures. This study investigates the effects of changes in the number of working women on household per capita consumption. We test the hypothesis that changes in the number of working women have a discernible impact on household final per capita consumption expenditures, due to their differing consumption propensities, by doing an empirical analysis based on panel data set of 36 OECD economies within the period 2000-2016. The results indicate that changes in the number of working women increase the household per capita consumption expenditures. The result also implies that age plays a significant role in working women consumption decision making and may lead to significant differences in aggregate consumption expenditure. These findings suggest the importance of understanding changes in the number of working women in planning for aggregate consumption mobilization and in the formulation of aggregate growth policies.

In this manuscript, we study the existence, uniqueness and various kinds of Ulam stability including Ulam-Hyers stability, generalized Ulam-Hyers stability, Ulam-Hyers-Rassias stability, and generalized Ulam-Hyers-Rassias stability of the solution to an implicit nonlinear fractional differential equations corresponding to an implicit integral boundary condition. We develop conditions for the existence and uniqueness by using the classical fixed point theorems such as Banach contraction principle and Schaefer's fixed point theorem. For stability, we utilize classical functional analysis. The main results are well illustrated with an example.

Dissertation, Universität Duisburg-Essen, 2016 Seit einigen Jahren rückt das E-Auto immer weiter in den Fokus der Öffentlichkeit. Durch diese Technologie sollen Alternativen zu konventionellen Fahrzeugen mit Verbrennungsmotor entstehen und zugleich soll eine Unabhängigkeit von politisch instabilen Erdöl liefernden Ländern geschaffen werden. Ein weiterer wichtiger Grund für diesen Trend ist jedoch auch die Einsparung des CO2-Ausstoßes, um so dem damit verbundenen Klimawandel entgegenzuwirken. Bei Einsatz von regenerativen Energiequellen wie Wind- oder Sonnenenergie wird der CO2-Austoß von E-Autos sogar auf null reduziert. Aus Verbrauchersicht hat das E-Auto allerdings zurzeit zwei wesentliche Nachteile: Erstens sind die Anschaffungskosten für eine Lithium-Ionen-Batterie sehr hoch. Nach Ende ihrer Lebensdauer muss die Lithium-Ionen-Batterie zudem wieder ausgetauscht werden, wodurch weitere zusätzliche Kosten entstehen. Zweitens beträgt die Reichweite eines durchschnittlichen E-Autos 150 km und halbiert sich im Winter. In dieser Arbeit wird daher ein semi-empirisches thermoelektrisches Modell einer 50 Ah Lithium-Eisenphosphat-Batteriezelle (LFP-Batteriezelle) in SimulationX erstellt. Das Rint-Modell beschreibt das elektrische Verhalten der LFP-Batteriezelle. Die elektrischen Parameter wie die offene Klemmspannung U_oc, der Ladewiderstand R_ch und der Entladewiderstand R_disch werden bei unterschiedlichen Umgebungstemperaturen (0 °C, 25 °C, 40 °C) und Entladetiefen (0/ 0,2/ 0,4/ 0,6/ 0,8/ 1) mittels XCTS-Batterietestsystem bestimmt. Das thermische Modell berücksichtigt dabei die Wärmeaufnahme bzw. -abgabe über Wärmeleitung, Wärmekonvektion, Wärmestrahlung sowie den Einfluss einer internen Wärmequelle. Die erforderlichen thermischen Parameter wie Wärmeleitfähigkeit λ, Wärmekapazität c_p und Emissionskoeffizient ε werden durch die in der Fachliteratur bekannten theoretischen Methoden erfasst. Außerdem berücksichtigt das Modell die kalendarische und zyklische Alterung der LFP-Batteriezelle und ist modular aufgebaut. Die Ermittlung der kalendarischen und zyklischen Alterung der LFP-Batteriezellen erfolgt an einem Batterieprüfstand bei unterschiedlichen Umgebungstemperaturen (0 °C, 25 °C, 40 °C), Entladeströmen (25 A, 50 A, 100 A), Entladetiefen (0,2/ 0,5/ 0,8) sowie Ladezustandsbereichen (1-0,8/ 1-0,5/ 1-0,2). Durch die modulare Gestaltung kann überdies eine LFP-Batterie mit beliebiger Anzahl von LFP-Batteriezellen generiert werden. Anschließend wird das Batteriemodell von SimulationX über eine S-function nach Matlab/Simulink exportiert und auf Echtzeitfähigkeit geprüft. Der wissenschaftliche Beitrag dieser Arbeit besteht somit in der gesamtheitlichen Betrachtung und Auslegung einer LFP-Batterie für ein Minicar E-Auto (A-Segment) und ein unteres Mittelklasse E-Auto (C-Segment) hinsichtlich Lebensdauer, Batteriepackaging (i.e. der Zellenanzahl), Wärmeentwicklung, Fahrzeugreichweite sowie Batteriekosten. Since the past few years, the electric car has moved more and more into the focus of public interest. Through this technology, new alternatives to conventional vehicles with combustion engines should be developed and thereby independence from politically unstable oil supplying countries should be achieved. Another important reason for this trend, however, is also the reduction of the CO2 emission in order to mitigate the associated climate change. When renewable energy sources like wind or solar power are used, the CO2 emission of electric cars is even reduced to zero. Yet, from the customer’s perspective, at present, the electric car has two fundamental disadvantages: Firstly, the acquisition costs for a Lithium-Ion battery are very high and after its lifecycle has expired, the Lithium-Ion battery has to be replaced, causing further additional costs. Secondly, the reach of an average electric car amounts to 150 km, a distance which is reduced by half in winter. Therefore, in this thesis, a semi-empirical thermo-electrical model of a 50 Ah Li-ion Iron Phosphate Cell (LFP battery cell) is designed with SimulationX. The resulting Rint model describes the electric behaviour of the LFP battery cell. The electrical parameters like the open circuit voltage U_oc, the charging resistor R_ch and the discharge resistor R_disch are determined at different ambient temperatures (0 °C, 25 °C, 40 °C) and at different depths of discharge (0/ 0.2/ 0.4/ 0.6/ 0.8/ 1) using the XCTS Battery Test System. The thermal model, on the other hand, takes into consideration heat absorption respectively heat emission through heat conduction, thermal convection, thermal radiation or the respective influence of an internal heat source. The needed thermal parameters like the heat conductivity λ, the thermal capacity c_p and the coefficient of emission ε are measured by means of the theoretical methods that are commonly known in the scientific literature. Furthermore, the here elaborated model takes into account the calendrical and cyclical aging of the LFP battery cell and is based on a modular design. By means of a battery test station, the calendrical and cyclical aging of the LFP battery cells is measured at different ambient temperatures (0 °C, 25 °C, 40 °C), for different discharging currents (25 A, 50 A, 100 A), at different depths of discharge (0.2/ 0.5/ 0.8) and with respect to different charging state ranges (1-0.8/ 1-0.5/ 1-0.2). Besides, and due to the modular structure, the LFP battery can be designed for any number of LFP battery cells. In a next step, using an S-function, the battery model is exported from SimulationX to Matlab/Simulink and tested for its real-time capability. Hence, the scientific contribution of the present thesis consist in its holistic assessment and dimensioning of an LFP battery for an electric mini car (in the A Class segment) and for an electric lower mid-range car (in the C Class segment) with respect to battery life cycle, battery packaging (i.e. the number of battery cells), heat development, vehicle range and battery costs.

In dieser Arbeit geht es um die kalendarische und zyklische Alterung einer 50 Ah Lithium-Eisenphosphat-Batteriezelle (LFP-Batteriezelle). Dabei wird die Abnahme der Kapazität der LFP-Batteriezelle während der kalendarischen und zyklischen Alterung ermittelt. Die LFP-Batteriezellen werden an einem Batterieprüfstand kalendarisch und zyklisch belastet. Die Stressfaktoren der kalendarischen Alterung sind drei verschiedene Temperaturen (0 °C, 25 °C, 40 °C) und Ladezustandsbereiche (∆SOC) von 1-0,8/ 0,8-0,5 und 0,5-0,2. Zur Ermittlung der kalendarischen Alterung wird in regelmäßigen Zeitabständen das Verhältnis A_cal der irreversiblen Kapazität C_(cal,irv) aufgrund der kalendarischen Alterung und der Nennkapazität C gebildet. Zur Ermittlung der zyklischen Alterung wird die LFP-Batteriezelle ebenfalls bei Temperaturen von 0 °C, 25 °C und 40 °C gelagert und mit Entladeströmen von 25 A, 50 A und 100 A jeweils um 0,2/ 0,5 und 0,8 DOD entladen. Anschließend wird das Verhältnis A_cyc der irreversiblen Kapazität C_(cyc,irv) aufgrund der zyklischen Alterung und der Nennkapazität C bestimmt.

In this work, a series of ab-initio calculations based on density functional theory is presented. We investigated the properties of water and the inclusion complexes of cyclodextrins with various guest compounds such as phenol, aspirin, pinacyanol chloride dye and binaphtyl molecules in the environment of water as solvent. Our investigation of water includes the cluster units of water, the bulk properties of the liquid water and the crystalline ice structure. Some equilibrium structures of water clusters were prepared and their binding energies were calculated with the self-consistency density functional tight binding (SCC-DFTB) method. The global minimum water clusters of TIP4P classical modelled potential were also calculated using the DFTB method and Vienna Ab-initio Simulation Package (VASP). All results show a non-linear behaviour of the binding energy per water molecule against water cluster size with some anomalies found for the lower clusters between 4 and 8 molecules. We also calculated the melting temperatures of these water clusters having solid-like behaviour by heating. Though, the melting region of the heated structures is not well defined as a result of the pronounced fluctuations of the bonding network of the system giving rise to fluctuations in the observed properties, but nevertheless the range where the breakdown occurs was defined as the melting temperature of the clusters. The bulk properties of the liquid, such as radial distribution functions, calculated with the VASP method show good agreement with neutron diffraction scattering data with respect to positions and height of the peaks. The DFTB method gives good positions of the peaks but with too broad peaks due the approximations on which the method relies, which makes it less accurate. Due to the complexity of the hydrogen bonding network, it is difficult to obtain the real ice structure by mere cooling liquid water under normal condition without imposing external constraints such as extreme external pressure or electric field. A special rule of proton ordering was followed in order to prepare the real ice structure for our calculations. We succeeded in preparing a hexagonal tetrahedrally coordinated type of ice. The statical properties of this ice were calculated as well as the phonon spectra. The results were compared with neutron diffraction data and other available ab-initio} calculations. The molecular dynamics simulations of inclusion complexes of beta-cyclodextrin with each of these guest molecules, phenol and aspirin show the encapsulation which are in good agreement with dichroism measurements. The inclusion complex of a dimer calculation of pinacyanol dye with some droplet of water inside gamma-cyclodextrin shows structural properties which can be ascribed to the experimental observation of UV/CD spectra of the chromophores, in which there is a split of the excited states of the monomer units. The calculations on chiral molecules of binaphtyl-beta-cyclodextrin complex shows a longitudinal axis as preferred axis of entry of the binaphtyl during the inclusion process rather than an axial propagation in agreement with circular dichroism measurements. The investigated chiral separation ability of beta-cyclodextrin on the enantiomeric pair of this compound R and S, which differ in symmetry only by reflection, shows that the S-enantiomer has lower energy than the R-enantiomer as revealed by our ab-initio calculations.