Water Emissions Trading in Europe: A Literature Overview and Discussion of Opportunities

This report is about Water Emissions Trading (WET or Water Quality Trading) in Europe. The goal is to inform about the basic principles, provide an overview of studies done in Europe, and suggest some future opportunities for WET in Europe

Fast evaluation of the Rayleigh integral and applications to inverse acoustics

In this paper we present a fast evaluation of the Rayleigh integral, which leads to fast and robust solutions in inverse acoustics. The method commonly used to reconstruct acoustic sources on a plane in space is Planar Nearfield Acoustic Holography (PNAH). Some of the most important recent improvements in PNAH address the alleviation of spatial windowing effects that arise due to the application of a Fast Fourier Transform to a finite spatial measurement grid. Although these improvements have led to an increase in the accuracy of the method, errors such as leakage and edge degradation can not be removed completely. Such errors do not occur when numerical models such as the Boundary Element Method (BEM) are used.Moreover, the forward models involved converge to the exact solution as the number of elements tends to infinity. However, the time and computer memory needed to solve these problems up to an acceptable accuracy is large. We present a fast (O(n log n) per iteration) and memory efficient (O(n)) solution to the planar acoustic problem by exploiting the fact that the transfer matrix associated with a numerical implementation of the Rayleigh integral is Toeplitz. In this paper we will address both the fundamentals of the method and its application in inverse acoustics. Special attention will be paid to comparison between experimental results from PNAH, IBEM and the proposed method

Near Source Acoustical Particle Velocity Measurements with Ambient Noise

An acoustical measurement very near a structure can be a cheap alternative to other contactless vibration measurement techniques such as laser vibrometry. However, measurements of the acoustical pressure suffer greatly from ambient noise, making these measurements unsuitable for many industrial applications. De Bree and Druyvesteyn suggested that a measurement of the acoustical particle velocity does not have this drawback and provided theory and qualitative measurement results [1]. We present quantitative measurement results of the relative noise contribution in pressure and particle velocity measurements. The ratio of these quantities receives special attention. The model used in previous research is a lumped model, in which some important aspects are neglected. We present results of a numerical model of the vibrating structure and the air. The numerical model and the measurements indicate the same trends but the lumped model does not describe the trends well. Nevertheless, this study also suggests that the sensitivity to background noise is generally considerably greater in pressure measurement than in a particle velocity measurement

Distributed multilevel optimization for complex structures

Optimization problems concerning complex structures with many design variables may entail an unacceptable computational cost. This problem can be reduced considerably with a multilevel approach: A structure consisting of several components is optimized as a whole (global) as well as on the component level. In this paper, an optimization method is discussed with applications in the assessment of the impact of new design considerations in the development of a structure. A strategy based on fully stressed design is applied for optimization problems in linear statics. A global model is used to calculate the interactions (e.g., loads) for each of the components. These components are then optimized using the prescribed interactions, followed by a new global calculation to update the interactions. Mixed discrete and continuous design variables as well as different design configurations are possible. An application of this strategy is presented in the form of the full optimization of a vertical tail plane center box of a generic large passenger aircraft. In linear dynamics, the parametrization of the component interactions is problematic due to the frequency dependence. Hence, a modified method is presented in which the speed of component mode synthesis is used to avoid this parametrization. This method is applied to a simple test case that originates from noise control. \u

Domain studies of CoCr with perpendicular anisotropy

R.F. Magnetron sputtered CoCr films (79/21 at%) with various thicknesses are magnetically characterized. The domain structure is observed by digitally enhanced Kerr microscopy and depends on the Hc/Hk values of the samples. For low and high coercivity films a comparison is made between the measured VSM hysteresis, domain period and a theoretical domain model. The domain shape is a function of the magnetic history of the sample and the bending created by the deposition process

Straddle Option Profitability In Corporate Lawsuits

The current study investigates whether abnormal returns may be gained by purchasing a straddle position prior to a verdict or settlement announcement in a lawsuit.  The basis for the hypothesis stems from behavioral finance—more specifically, the Overreaction Hypothesis.  Using CAPM expected rates of return and comparisons of 31 lawsuit firms’ straddle returns, three new straddle trading strategies are devised.  Within the sample of lawsuits, abnormal returns are evident for the three strategies.  The results and their implications support behavioral finance and the Overreaction Hypothesis and thus refute the Efficient Markets Hypothesis

Unexpected Scaling of the Performance of Carbon Nanotube Transistors

We show that carbon nanotube transistors exhibit scaling that is qualitatively different than conventional transistors. The performance depends in an unexpected way on both the thickness and the dielectric constant of the gate oxide. Experimental measurements and theoretical calculations provide a consistent understanding of the scaling, which reflects the very different device physics of a Schottky barrier transistor with a quasi-one-dimensional channel contacting a sharp edge. A simple analytic model gives explicit scaling expressions for key device parameters such as subthreshold slope, turn-on voltage, and transconductance.Comment: 4 pages, 4 figure

The role of callose deposits during infection of two downy mildew-tolerant and two-susceptible Vitis cultivars

Semithin sections of leaves from four cultivars were analysed for callose deposition after infection with Plasmopara viticola. Two of these cultivars are tolerant to this pathogen in the field (Orion, Phoenix), while the other two are susceptible (Kerner, Riesling). Callose was not detectable during the first 5 days after experimental inoculation. During late stages of the infection cycle however, callose deposits could be found in tolerant as well as in susceptible grapes. During the fungal infection of tolerant plants hyphal development stops 3 to 4 days post infection indicating that mechanisms other than callose deposition are the main factors of tolerance

The role of hairs on the wettability of grapevine (Vitis spp.) leaves

Hairs represent an important physico-chemical factor on abaxial leaf surfaces of grapevine and can influence the wettability of leaves. This was demonstrated by scanning electron micrographs and monitored with a new method using a torsion balance. Forces necessary to remove water droplets of distinct size from leaves were lower in case of pubescent (0,2-0,4 mN) compared to non-pubescent vine leaves (0,4-1,2 mN). Depending on the number of hairs and their surface structure the deposition and distribution of water droplets originating from dew and rain can be prevented due to weak adhesion. Thus, surface features enabling water droplets to pearl off may reduce the probability of infection by fungal spores