Implementation issues in product line scoping

Often product line engineering is treated similar to the waterfall model in traditional software engineering, i.e., the different phases (scoping, analysis, architecting, implementation) are treated as if they could be clearly separated and would follow each other in an ordered fashion. However, in practice strong interactions between the individual phases become apparent. In particular, how implementation is done has a strong impact on economic aspects of the project and thus how to adequately plan it. Hence, assessing these relationships adequately in the beginning has a strong impact on performing a product line project right. In this paper we present a framework that helps in exactly this task. It captures on an abstract level the relationships between scoping information and implementation aspects and thus allows to provide rough guidance on implementation aspects of the project. We will also discuss the application of our framework to a specific industrial project

Biology and management of Japanese beetle

Abstract supplied by cataloger."This publication is partially funded by a USDA NIFA grant in the Crop Protection and Pest Management Program."An informational article about how to identify and manage Japanese beetles.Written by: Kelsey J. Benthall (GRA, Division of Plant Sciences, University of Missouri), Emily R. Althoff (GRA, Division of Plant Sciences, University of Missouri), Kevin B. Rice (Assistant Professor, Division of Plant Sciences, University of Missouri)New 7/2

The genetic and environmental contributions to attention deficit hyperactivity disorder as measured by the Conners' Rating Scales-revised

Objective: The majority of published reports on twin studies of attention deficit hyperactivity disorder (ADHD) have indicated robust additive genetic influences and unique environmental influences. These studies typically used DSM ADHD symptoms collected by telephone or interviews with mothers. The purpose of this study was to test the genetic architecture of ADHD by using the ADHD index from Conners' Rating Scales - Revised. Method: From the Conners' scale forms, data for the ADHD index were collected from the mothers of 1,595 7-year-old twin pairs from the Netherlands Twin Registry. Rates of ADHD diagnoses were computed by using Conners' gender- and age-specific cutoff points. Contributions from additive, dominant, unique environmental, interaction, and gender effects were computed by using gender-genetic models. Results: The prevalence of ADHD across the sample of 7-year-old twin pairs was about 4% according to the mothers' reports, consistent with other reported rates of ADHD. However, using the gender norms provided with the ADHD index, the authors found slightly higher rates of ADHD in girls than previously reported. Genetic analyses yielded a model that includes genetic dominance (48%), additive genetic factors (30%), and unique environmental factors (22%). Conclusions: The ADHD index from Conners' Rating Scales - Revised identified an appropriate percentage of children across this epidemiologic twin sample as being at risk for ADHD. The results of the genetic analyses are consistent with prior reports that ADHD is predominantly influenced by genetic factors that are both dominant and additive

Effects of Surface Coatings on the Joint Formation During Magnetic Pulse Welding in Tube-to-Cylinder Configuration

Magnetic Pulse Welding (MPW) is a joining technique favorable for the generation of strong atomic bonded areas between different metals, e.g. aluminum and steel. Brittle intermetallic phases can be avoided due to the high-speed collision and the absence of external heat. The demand for the use of this technique in industries like automotive and plant engineering rises. However, workpieces used in these fields are often coated, e.g. in order to improve the corrosion resistance. Since the weld quality depends on the material’s behavior at the collision zone, surface layers in that region have to be taken into account as well. This work investigates the influences of different coating types. Aluminum to steel welding is used as an example system. On the inner steel part (C45) coatings like zinc, nickel and chrome are applied, while the aluminum flyer tubes (EN AW-6060) are anodized, chromated and passivated. Welding tests are performed using two different welding systems with varying discharging frequencies and four geometrical part setups. For all combinations, the flyer velocity during the process is measured by Photon Doppler Velocimetry (PDV). By using the uncoated material combination as a reference, the removal of surface layers due to jetting is analyzed. Finally, the weld quality is characterized in peel tests, shear-push tests and by the help of metallographic analysis. It is found that certain coatings improve the joint formation, while others are obstructive for the performance of MPW. Some coatings have no influence on the joining process at all

Leading particle effect, inelasticity and the connection between average multiplicities in {\bf e+e−e^+e^-} and {\bf pppp} processes

The Regge-Mueller formalism is used to describe the inclusive spectrum of the proton in $p p$ collisions. From such a description the energy dependences of both average inelasticity and leading proton multiplicity are calculated. These quantities are then used to establish the connection between the average charged particle multiplicities measured in {\bf $e^+e^-$} and {\bf $pp/{\bar p}p$} processes. The description obtained for the leading proton cross section implies that Feynman scaling is strongly violated only at the extreme values of $x_F$, that is at the central region ($x_F \approx 0$) and at the diffraction region ($x_F \approx 1$), while it is approximately observed in the intermediate region of the spectrum.Comment: 20 pages, 10 figures, to be published in Physical Review

Photon Structure and Quantum Fluctuation

Photon structure derives from quantum fluctuation in quantum field theory to fermion and anti-fermion, and has been an experimentally established feature of electrodynamics since the discovery of the positron. In hadronic physics, the observation of factorisable photon structure is similarly a fundamental test of the quantum field theory Quantum Chromodynamics (QCD). An overview of measurements of hadronic photon structure in e+e- and ep interactions is presented, and comparison made with theoretical expectation, drawing on the essential features of photon fluctuation into quark and anti-quark in QCD.Comment: 29 pages, 15 figures, to appear in Philosophical Transactions of the Royal Society of London (Series A: Mathematical, Physical and Engineering Sciences

Influence of the Wall Thicknesses on the Joint Quality During Magnetic Pulse Welding in Tube-to-Tube Configuration

The implementation of multi-material concepts, for example, in automotive engineering or aerospace technologies, requires adequate joining techniques. The Magnetic Pulse Welding (MPW) process allows for joining both similar and dissimilar materials without additional mechanical elements, chemical binders, or adverse influences of heat on the joining partners. In this process, an electro-conductive at (‘flyer’) part is accelerated by Lorentz forces and impacts the inner (‘parent’) part under high velocity and high pressure, leading to the formation of a metallurgical joint. Besides joining of sheets and tubes to solid cylinders, the connection of two tubes is of particular interest due to the increased lightweight potential. The present paper focuses on the MPW of aluminum (EN AW-6060) to steel (C45) tubes. An experimental study was performed, in which the wall thickness of the parent part was reduced successively. The deformation behavior of both the flyer and parent parts was recorded during the experiments by a two-probe Photon Doppler Velocimeter (PDV). The final shape of the joined specimens was analyzed by a 3D digitizer. An instrumented peel test was used for the determination of the weld quality. It was found that defect-free MPW of aluminum tubes on steel tubes without supporting mandrel is possible

Influence of the Free Compression Stage on Magnetic Pulse Welding of Tubes

In magnetic pulse welding (MPW) of tubular parts, the acceleration of the ‘flyer’ part typically corresponds to a free electromagnetic compression (EMC) process over the distance of the initial standoff between the outer and inner tube. During this process stage, already significant plastic strains occur. In addition, wrinkling is a phenomenon frequently observed during EMC. In this manuscript, influencing factors on the wrinkling effect are identified, taking the initial geometry of the flyer tube and its manufacturing process into account. Moreover, a link between the strains and wrinkles caused by the tube compression and the MPW process is made. An experimental study is performed aiming for the quantification of the plastic deformation during EMC. The effect of this deformation on the stability and adhesion of brittle surface layers is analyzed. Accompanying numerical simulations help to understand the wrinkle formation and its influencing factors. Based on the results, hints for an improved process design of MPW are given