Optimal designs for nonlinear regression models with respect to non-informative priors

In nonlinear regression models the Fisher information depends on the parameters of the model. Consequently, optimal designs maximizing some functional of the information matrix cannot be implemented directly but require some preliminary knowledge about the unknown parameters. Bayesian optimality criteria provide an attractive solution to this problem. These criteria depend sensitively on a reasonable specification of a prior distribution for the model parameters which might not be available in all applications. In this paper we investigate Bayesian optimality criteria with non-informative prior dis- tributions. In particular, we study the Jeffreys and the Berger-Bernardo prior for which the corresponding optimality criteria are not necessarily concave. Several examples are investigated where optimal designs with respect to the new criteria are calculated and compared to Bayesian optimal designs based on a uniform and a functional uniform prior.Comment: Keywords: optimal design; Bayesian optimality criteria; non-informative prior; Jeffreys prior; reference prior; polynomial regression; canonical moments; heteroscedasticity Pages: 21 Figures:

Endogenous growth, technical change and pollution control. Insights from a Schumpeterian growth model with productivity growth and green innovation

This thesis studies economic growth and pollution control in a Schumpeterian model with endogenous rate and direction of technical change. Economic growth results from growth in the quantity and productivity of polluting intermediate goods. Pollution is linked to the quantity of intermediates. Productivity growth is not directly polluting but has an indirect effect on pollution which is a priory ambiguous: Higher productivity helps to use polluting inputs more efficiently and decrease their share in GDP. However, it also increases their marginal product, which stimulates intermediate demand and may thereby reduce or offset possible efficiency gains. The latter is called a rebound effect. Pollution growth can be controlled by lowering the pollution intensity of a given quantity of intermediates through costly research (green innovation) and by restricting the rebound effect of productivity growth by decreasing the share of intermediate quantity in GDP. Without clean substitutes, saving on polluting inputs implies that potential GDP and consumption growth is foregone (deceleration). While neither green innovation nor deceleration is chosen under laissez-faire, both contribute to long-run optimal pollution control for empirically relevant parameter values. Neglecting either possibility to restrict pollution growth weakens the prospects for persistent economic growth in the long-run optimal solution as well as the long-run optimal growth rate. A substantial share of worldwide emissions is generated by the use of exhaustible resources like fossil fuels. In an extension of the baseline model, the effects of resource scarcity on the environment, long-run growth and the direction of technical change are analyzed. It is shown that the need to restrict pollution growth may reduce optimal resource use in a way that the resource is never exhausted in the optimal solution if the initial stock is large enough

Важность информационных технологий в области финансов

The article describes the impact of information technology on the different fields of human activities. Emphasis is given to the financial management of the enterprise and in no case must not forget about personal finance management

Characterization of fundamental catalytic properties of MoS2/WS2 nanotubes and nanoclusters for desulfurization catalysis - a surface temperature study

The prior project consisted of two main project lines. First, characterization of novel nanomaterials for hydrodesulfurization (HDS) applications. Second, studying more traditional model systems for HDS such as vapor-deposited silica-supported Mo and MoSx clusters. In the first subproject, we studied WS2 and MoS2 fullerene-like nanoparticles as well as WS2 nanotubes. Thiophene (C4H4S) was used as the probe molecule. Interestingly, metallic and sulfur-like adsorption sites could be identified on the silica-supported fullerene-particles system. Similar structures are seen for the traditional system (vapor-deposited clusters). Thus, this may be a kinetics fingerprint feature of modern HDS model systems. In addition, kinetics data allowed characterization of the different adsorption sites for thiophene on and inside WS2 nanotube bundles. The latter is a unique feature of nanotubes that has not been reported before for any inorganic nanotube system; however, examples are known for carbon nanotubes, including prior work of the PI. Although HDS has been studied for decades, utilizing nanotubes as nanosized HDS reactors has never been tried before, as far as we know. This is of interest from a fundamental perspective. Unfortunately, the HDS activity of the nanocatalysts at ultra-high vacuum (UHV) conditions was close to the detection limit of our techniques. Therefore, we propose to run experiments at ambient pressure on related nanopowder samples as part of the renewal application utilizing a now-available GC (gas chromatograph) setup. In addition, Ni and Co doped nanocatalyts are proposed for study. These dopants will boost the catalytic activity. In the second subproject of the prior grant, we studied HDS-related chemistry on more traditional supported cluster catalysts. Mo clusters supported by physical vapor deposition (PVD) on silica have been characterized. Two reaction pathways are evident when adsorbing thiophene on Mo and MoSx clusters: molecular adsorption and dissociation. PVD Mo clusters turned out to be very reactive toward thiophene bond activation. Sulfur and carbon residuals form, which poison the catalyst and sulfide the Mo clusters. Sulfided silica-supported MoSx samples are not reactive toward thiophene bond activation. In addition to S and C deposits, H2, H2S, and small organic molecules were detected in the gas phase. Catalyst reactivation procedures, including O2 and atomic hydrogen treatments, have been tested. Cluster size effects have been seen: thiophene adsorbs molecularly with larger binding energies on smaller clusters. However, larger clusters have smaller activation energy for C4H4S bond activation than smaller clusters. The latter is consistent with early catalysis studies. Kinetics and dynamics parameters have been determined quantitatively. We spent a significant amount of time on upgrades of our equipment. A 2nd-hand refurbished X-ray photoelectron spectrometer (XPS) has been integrated into the existing molecular beam scattering system and is already operational (supported by the DoE supplemental grant available in October 2009). We also added a time of flight (TOF) system to the beam scattering apparatus and improved on the accessible impact energy range (new nozzle heater and gas mixing manifold) for the beam scattering experiments. In addition, a GC-based powder atmospheric flow reactor for studies on powder samples is now operational. Furthermore, a 2nd UHV kinetics system has been upgraded as well. In summary, mostly single crystal systems have so far been considered in basic science studies about HDS. Industrial catalysts, however, can be better approximated with the supported cluster systems that we studied in this project. Furthermore, an entirely new class of HDS systems, namely fullerene-like particles and inorganic nanotubes, has been included. Studying new materials and systems has the potential to impact science and technology. The systems investigated are closely related to energy and environmental-related surface science/catalysis. This prior project, conducted at NDSU by a small team, resulted in a total of 14 printed publications,1-5, 7-12, 14, 19, 20eight months before the end of the funding period. In addition, collaborators at national laboratories and abroad were part of the projects, as proposed. More specifically, projects about HDS on MoS2 and WS2 inorganic fullerene-like nanoparticles,1, 5 inorganic WS2 nanotubes,2 Mo and MoS2 vapor-deposited nanoclusters,3 modeling,19 reviews/book chapter,7, 11 and side projects8-10 have been conducted, as proposed, acknowledging solely (exception ref.7) funding from this grant. A list of publications and coworkers is given in sect. 6

Influence of Specific Energy Inhomogeneity on the CO2 Splitting Performance in a High-Power Plasma Jet

Plasma-based CO2 conversion is a promising pathway towards greenhouse gas recycling. In the corresponding research field, various types of plasma reactors are applied for carbon dioxide dissociation. So far, spatial inhomogeneities of the specific energy (SEI) distribution in plasma generators, e.g., induced by non-uniform heating or an inhomogeneous mass distribution, are not the focus of the investigations. In this work, the spatial inhomogeneity of mass-specific enthalpy in the plasma jet of the inductive plasma generator IPG4 at the Institute of Space Systems (IRS) is examined. For this, the mean mass-specific enthalpy as well as the radial distribution of the local enthalpy are measured using plasma probes. Moreover, the influence of the determined specific enthalpy inhomogeneity on the CO2 splitting performance is quantified. It is shown that an inhomogeneous radial distribution of the specific energy can significantly lower the carbon dioxide conversion, compared to a homogeneous case. With regards to IPG4, the performance reduction is 16 %.Comment: 30 pages, 12 figure

Remote work as a universal solution for companies? A qualitative study of German companies' employer branding between demands and challenges of implementing work-family-flexibility measures

This research project examined the role of remote work as part of familyoriented employer branding. The literature review indicates that there is no underlying research connecting the topics of remote work with strategic family-oriented employer branding. To gain insights into this rather unexplored topic, this project conducted 17 semi-structured guided interviews with interviewees from both Communication and Human Resource Departments representing different industries and companies of various sizes. The analysis and evaluation showed that there is no strategic connection between the use of remote work in employer branding and family issues within the companies yet. The usage of family-oriented measures depends on multiple factors and puts companies through a serious stress test. Over the last years, the demand for remote work increased significantly. This trend leads to new challenges and issues companies need to tackle. In summary, remote work can be viewed as an important part in a set of family-oriented employer branding measures. The future direction of this topic is uncertain and requires further research

Adsorption of Water on Simulated Moon Dust Samples

A lunar regolith simulant dust sample (JSC-1a) supported on a silica wafer (SiO2/Si(111)) has been characterized by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX), and Auger electron spectroscopy (AES). The adsorption kinetics of water has been studied primarily by thermal desorption spectroscopy (TDS) and also by collecting isothermal adsorption transients. The support has been characterized by water TDS. JSC-1a consists mostly of aluminosilicate glass and other minerals containing Fe, Na, Ca, and Mg. The particle sizes span the range from a few microns up to 100 microns. At small exposures, H2O TDS is characterized by broad (100 to 450 K) structures; at large exposures distinct TDS peaks emerge that are assigned to amorphous solid water (145 K) and crystalline ice (165 K). Water dissociates on JSC-1a at small exposures but not on the bare silica support. It appears that rather porous condensed ice layers form at large exposures. At thermal impact energies, the initial adsorption probability amounts to 0.92+/-0.05

PRAS40 suppresses atherogenesis through inhibition of mTORC1-dependent pro-inflammatory signaling in endothelial cells

Endothelial pro-inflammatory activation plays a pivotal role in atherosclerosis, and many pro-inflammatory and atherogenic signals converge upon mechanistic target of rapamycin (mTOR). Inhibitors of mTOR complex 1 (mTORC1) reduced atherosclerosis in preclinical studies, but side effects including insulin resistance and dyslipidemia limit their clinical use in this context. Therefore, we investigated PRAS40, a cell type-specific endogenous modulator of mTORC1, as alternative target. Indeed, we previously found PRAS40 gene therapy to improve metabolic profile; however, its function in endothelial cells and its role in atherosclerosis remain unknown. Here we show that PRAS40 negatively regulates endothelial mTORC1 and pro-inflammatory signaling. Knockdown of PRAS40 in endothelial cells promoted TNFα-induced mTORC1 signaling, proliferation, upregulation of inflammatory markers and monocyte recruitment. In contrast, PRAS40-overexpression blocked mTORC1 and all measures of pro-inflammatory signaling. These effects were mimicked by pharmacological mTORC1-inhibition with torin1. In an in vivo model of atherogenic remodeling, mice with induced endothelium-specific PRAS40 deficiency showed enhanced endothelial pro-inflammatory activation as well as increased neointimal hyperplasia and atherosclerotic lesion formation. These data indicate that PRAS40 suppresses atherosclerosis via inhibition of endothelial mTORC1-mediated pro-inflammatory signaling. In conjunction with its favourable effects on metabolic homeostasis, this renders PRAS40 a potential target for the treatment of atherosclerosis