The parameterization method for center manifolds

In this paper, we present a generalization of the parameterization method, introduced by Cabr\'{e}, Fontich and De la Llave, to center manifolds associated to non-hyperbolic fixed points of discrete dynamical systems. As a byproduct, we find a new proof for the existence and regularity of center manifolds. However, in contrast to the classical center manifold theorem, our parameterization method will simultaneously obtain the center manifold and its conjugate center dynamical system. Furthermore, we will provide bounds on the error between approximations of the center manifold and the actual center manifold, as well as bounds for the error in the conjugate dynamical system

Energy from streaming current and potential

It is investigated how much energy can be delivered by a streaming current source. A streaming current and subsequent streaming potential originate when double layer charge is transported by hydrodynamic flow. Theory and a network model of such a source is presented and initial experimental results are given, showing a supplied power of 20 nW obtained by a pressure difference of 1 atm over a glass porous plug, using a 1-mM KCl solution. It is indicated how the rather low mechanical-to-electrical energy conversion efficiency can be increased

Selective low concentration ammonia sensing in a microfluidic lab-on-a-chip

In the medical community, there is a considerable interest in a diagnostic breath analyzer for ammonia that is selectively enough to measure in exhaled air and small enough for the small volumes available in such an application. An indirect measurement system for low gaseous ammonia concentrations has been miniaturized and integrated on a chip in order to reach this goal. The detection limit of the system was calculated to be 1.1 parts per billion (ppb). The response time was determined to be 1.6 min with a gas How of 50 ml/min. The required gas volume for one measurement is therefore sufficiently small, although sampling assistance is required for breath analysis. The selectivity of the system is sufficient to measure ammonia concentrations in the low-ppb range. The system is even sufficiently selective to be used in environments that contain elevated carbon dioxide levels, like exhaled air. The lower ammonia concentration expected in diagnostic breath analysis applications, 50 ppb, was demonstrated to be detectable

Understanding Salesforce Behavior using Genetic Association Studies

__Abstract__ Using genetic association studies, this thesis aims to investigate the drivers of successful customer-salesperson interactions in a context where knowledge development has become crucial to the value creation process. Central to this thesis is the developing role of the contemporary sales professional. Coming from transaction-based selling and passing through an era of consultative selling sales strategies, we observe an emerging role for sales professionals as knowledge brokers. Indeed, sales professionals are crucial in linking different parties both within and outside their firm, creating a flow of knowledge between different members of the network. In line with this, salespeople should be able to shift their strategies from a short-term focus on the (immediate) sale, to a more long-term and customer-centred approach aimed on opportunity identification. The results presented in this thesis suggest that some sales professionals have an innate tendency to make an active effort to spot novel opportunities to help solve customers’ needs. To build long-term, valuable relationships with their customers, they will be most effective if they take a self-reliant and curious approach

The parameterization method for center manifolds

In this paper, we present a generalization of the parameterization method, introduced by Cabré, Fontich and De la Llave, to center manifolds associated to non-hyperbolic fixed points of discrete dynamical systems. As a byproduct, we find a new proof for the existence and regularity of center manifolds. However, in contrast to the classical center manifold theorem, our parameterization method will simultaneously obtain the center manifold and its conjugate center dynamical system. Furthermore, we will provide bounds on the error between approximations of the center manifold and the actual center manifold, as well as bounds for the error in the conjugate dynamical system

Activated carbon as a pseudo-reference electrode for potentiometric sensing inside concrete

The half-cell potential of the Activated carbon (AC), due to its high double layer capacitance (EDL), remains stable in high ionic electrolyte. The open circuit potential (OCV) of the AC, with EDL of 40 – 50 F, shows a stable potential (10 mV variation) over two weeks in the cement pore solution (sat. Ca(OH)2). The OCV is less sensitive to the pH change from pH 8 to 12 (range inside concrete). The potentiometric response of a Ag/AgCl vs. AC pseudo-reference shows a near-Nernstian response (-51 mV/decade). The AC electrode can be proposed as a pseudo-reference for the potentiometric monitoring inside concrete

Catalytic hydrogen peroxide decomposition La_1-xSr_xCoO_3-δ perovskite oxides

Lanthanide perovskite oxides are mentioned as material for hydrogen peroxide sensor because they can catalytically decompose hydrogen peroxide in an aqueous medium. The catalytic properties of these perovskite oxides to hydrogen peroxide are suggested due to their oxygen vacancies influenced by the oxide non-stoichiometry. In this paper, we investigate the catalytic hydrogen peroxide decomposition of a La1-xSrxCoO3-δ thin film with x = 0.7 for sensing application. The oxygen vacancy concentration in the oxide is estimated via the work function measurement using an electrolyte metal oxide semiconductor field effect transistor (EMOSFET) with a platinum remote gate. The experimental results show the catalytic properties of this oxide to hydrogen peroxide increases with increasing its non-stoichiometry, x

Acquisitions as a Real Options Bidding Game

This paper uses a unified treatment of real options and game theory to examine value appropriation in takeovers within a competitive environment of imperfect information. The integrated model considers a potential target as a shared real option on a bundle of resources. Competing potential buyers may sequentially perform due diligence and incur costs (option premium) to become informed about their firm-specific target value (underlying value) before making a bid (exercise price). The first player’s bid provides a signal on its own and rivals’ target value, thereby affecting potential bidders’ option value. The level of information costs and the option value, affected by heterogeneity between bidders (correlation), their expected target value, and uncertainty, determine value appropriation in acquisitions

Improved Conversion Rates in Drug Screening Applications sing Miniaturized Electrochemical Cells with Frit Channels

This paper reports a novel design of a miniaturized three-electrode electrochemical cell, the purpose of which is aimed at generating drug metabolites with a high conversion efficiency. The working electrode and the counter electrode are placed in two separate channels to isolate the reaction products generated at both electrodes. The novel design includes connecting channels between these two electrode channels to provide a uniform distribution of the current density over the entire working electrode. In addition, the effect of ohmic drop is decreased. Moreover, two flow resistors are included to ensure an equal flow of analyte through both electrode channels. Total conversion of fast reacting ions is achieved at flow rates up to at least 8 mu L/min, while the internal chip volume is only 175 nL. Using this electrochemical chip, the metabolism of mitoxantrone is studied by microchip electrospray ionization-mass spectrometry. At an oxidation potential of 700 mV, all known metabolites from direct oxidation are observed. The electrochemical chip performs equally well, compared to a commercially available cell, but at a 30-fold lower flow of reagents