Analyse der Störfestigkeit nichtlinearer Schaltungen gegenüber leitungsgebundenen elektromagnetischen Störungen mit multi-input Wiener/Hammerstein-Modellen

In dieser Arbeit wird der Einfluss von leitungsgebundenen Störungen untersucht, welche in einen beliebigen Eingang (Signaleingang, Spannungsversorgung, Masse-Potenzial, etc.) einer Analogschaltung einkoppeln. Die zu untersuchende Schaltung wird dazu durch einen Wiener/Hammerstein-Ansatz als nichtlineares System mit zwei Eingängen modelliert. Mit Hilfe dieses Blockmodells werden analytische Ausdrücke derjenigen Frequenzanteile bestimmt, die durch Intermodulationen zwischen Stör- und Eingangssignal am Ausgang einer Schaltung entstehen.BMBF/03X4604

An identification procedure of multi-input Wiener models for the distortion analysis of nonlinear circuits

In this contribution, a system identification procedure of a two-input Wiener model suitable for the analysis of the disturbance behavior of integrated nonlinear circuits is presented. The identified block model is comprised of two linear dynamic and one static nonlinear block, which are determined using an parameterized approach. In order to characterize the linear blocks, an correlation analysis using a white noise input in combination with a model reduction scheme is adopted. After having characterized the linear blocks, from the output spectrum under single tone excitation at each input a linear set of equations will be set up, whose solution gives the coefficients of the nonlinear block. By this data based black box approach, the distortion behavior of a nonlinear circuit under the influence of an interfering signal at an arbitrary input port can be determined. Such an interfering signal can be, for example, an electromagnetic interference signal which conductively couples into the port of consideration

Global life cycle paper flows, recycling metrics and material efficiency

Despite major improvements in recycling over the last decades, the pulp and paper sector is a significant contributor to global greenhouse gas emissions and other environmental pressures. Further reduction of virgin material requirements and environmental impacts requires a detailed understanding of the global material flows in paper production and consumption. This study constructs a Sankey diagram of global material flows in the paper life cycle, from primary inputs to end-of-life waste treatment, based on a review of publicly available data. It then analyses potential improvements in material flows and discusses recycling and material efficiency metrics. The article argues that the use of the collection rate as a recycling metric does not directly stimulate avoidance of virgin inputs and associated impacts. An alternative metric compares paper for recycling (recovered paper) with total fibrous inputs and indicates that the current rate is at just over half of the technical potential. Material efficiency metrics are found to be more useful if they relate to the reuse potential of wastes. The material balance developed in this research provides a solid basis for further study of global sustainable production and consumption of paper. The conclusions on recycling and efficiency should be considered for improving environmental performance assessment methods

The Marco Gonzalez Maya site, Ambergris Caye, Belize: assessing the impact of human activities by examining diachronic processes at the local scale

Research at the Maya archaeological site of Marco Gonzalez on Ambergris Caye in Belize is socio-ecological because human activities have been a factor in the formation and fluctuation of the local marine and terrestrial environments over time. The site is one of many on Belize's coast and cayes that exhibit anomalous vegetation and dark-coloured soils. These soils, although sought for cultivation, are not typical 'Amazonian Dark Earths' but instead are distinctive to the weathering of carbonate-rich anthropogenic deposits. We tentatively term these location-specific soils as Maya Dark Earths. Our research seeks to quantify the role of human activities in long-term environmental change and to develop strategies, specifically Life Cycle Assessment (LCA), that can be applied to environmental impact modelling today

Rehabilitation Following Hip Arthroscopy – A Systematic Review

CONTEXT: Rehabilitation following hip arthroscopy is an integral component of the clinical outcome of the procedure. Given the increase in quantity, complexity, and diversity of procedures performed, a need exists to define the role of rehabilitation following hip arthroscopy.OBJECTIVES: 1) To determine the current rehabilitation protocols utilized following hip arthroscopy in the current literature, 2) to determine if clinical outcomes are significantly different based on different post-operative rehabilitation protocols; and 3) to propose the best-available evidence-based rehabilitation program following hip arthroscopy.DATA SOURCES: Per PRISMA guidelines and checklist, Medline, SciVerse Scopus, SportDiscus, and Cochrane Central Register of Controlled Trials were searched.STUDY SELECTION: Level I-IV evidence clinical studies with minimum two-year follow-up reporting outcomes of hip arthroscopy with post-operative rehabilitation protocols described were included. DATA EXTRACTION: All study, subject, and surgery parameters were collected. All elements of rehabilitation were extracted and analyzed. Descriptive statistics were calculated. Study methodological quality was analyzed using the Modified Coleman Methodology Score (MCMS).RESULTS: 18 studies were included (2,092 subjects; 52% male, mean age 35.1 +/- 10.6 years, mean follow-up 3.2 +/- 1.0 years). Labral tear and femoroacetabular impingement were the most common diagnoses treated and labral debridement and femoral/acetabular osteochondroplasty the most common surgical techniques performed. Rehabilitation protocol parameters (weight-bearing, motion, strengthening, and return-to-sport) were poorly reported. Differences in clinical outcomes were unable to be assessed given heterogeneity in study reporting. Time-, phase-, goal-, and precaution-based guidelines were extracted and reported.CONCLUSIONS: The current literature of hip arthroscopy rehabilitation lacks high-quality evidence to support a speci

Evolution of E2 transition strength in deformed hafnium isotopes from new measurements on 172^{172}Hf, 174^{174}Hf, and 176^{176}Hf

The available data for E2 transition strengths in the region between neutron-deficient Hf and Pt isotopes are far from complete. More and precise data are needed to enhance the picture of structure evolution in this region and to test state-of-the-art nuclear models. In a simple model, the maximum collectivity is expected at the middle of the major shell. However, for actual nuclei, this picture may no longer be the case, and one should use a more realistic nuclear-structure model. We address this point by studying the spectroscopy of Hf. We remeasure the 2^+_1 half-lives of 172,174,176Hf, for which there is some disagreement in the literature. The main goal is to measure, for the first time, the half-lives of higher-lying states of the rotational band. The new results are compared to a theoretical calculation for absolute transition strengths. The half-lives were measured using \gamma-\gamma and conversion-electron-\gamma delayed coincidences with the fast timing method. For the determination of half-lives in the picosecond region, the generalized centroid difference method was applied. For the theoretical calculation of the spectroscopic properties, the interacting boson model is employed, whose Hamiltonian is determined based on microscopic energy-density functional calculations. The measured 2^+_1 half-lives disagree with results from earlier \gamma-\gamma fast timing measurements, but are in agreement with data from Coulomb excitation experiments and other methods. Half-lives of the 4^+_1 and 6^+_1 states were measured, as well as a lower limit for the 8^+_1 states. We show the importance of the mass-dependence of effective boson charge in the description of E2 transition rates in chains of nuclei. It encourages further studies of the microscopic origin of this mass dependence. New data on transition rates in nuclei from neighboring isotopic chains could support these studies.Comment: 16 pages, 16 figures, 7 tables; Abstract shortened due to character limi

Knowledge base to facilitate anthropogenic resource assessment

Non-energy mineral resources such as iron and ferro-alloy metals, non-ferrous metals, precious metals, industrial minerals and construction materials are essential for industrial production, the prosperity of nations and modern living standards

Recognising waste use potential to achieve a circular economy

Waste management historically focused on the protection of human health and the natural environment from the impacts of littering and dispersion of pollutants. An additional and more recent concern is the resource value of waste. Our analysis shows that the regulatory concept of waste in the European Union, which comprises environmental principles, the legal definition of waste, legal requirements, and policy implementation, is not fit for addressing this concern. The legal definition of waste overlooks the context of waste, fails to consider the interests of the waste user as opposed to the waste holder, and aims to control the impacts of careless discarding rather than stimulating careful discarding. To address these challenges, we suggest a legal requirement to recognise the potential of waste to be used, operationalised by formulating a waste use potential, which expresses how and how much waste can be used as a resource, given enabling conditions. Recognition of waste use potential highlights local opportunities for reuse and recovery, reduces the likelihood of careless discarding, and reveals the interests of possible waste users to the waste holder. The waste use potential may be employed in the formulation and evaluation of policies for industrial and municipal solid waste in a circular economy

Enumeration of islets by nuclei counting and light microscopic analysis

Author Manuscript 2011 May 1.Islet enumeration in impure preparations by conventional dithizone staining and visual counting is inaccurate and operator dependent. We examined nuclei counting for measuring the total number of cells in islet preparations, and we combined it with morphological analysis by light microscopy (LM) for estimating the volume fraction of islets in impure preparations. Cells and islets were disrupted with lysis solution and shear, and accuracy of counting successively diluted nuclei suspensions was verified with (1) visual counting in a hemocytometer after staining with crystal violet, and automatic counting by (2) aperture electrical resistance measurement and (3) flow cytometer measurement after staining with 7-aminoactinomycin-D. DNA content averaged 6.5 and 6.9 pg of DNA per cell for rat and human islets, respectively, in agreement with literature estimates. With pure rat islet preparations, precision improved with increasing counts, and samples with about greater than or equal to 160 islets provided a coefficient of variation of about 6%. Aliquots of human islet preparations were processed for LM analysis by stereological point counting. Total nuclei counts and islet volume fraction from LM analysis were combined to obtain the number of islet equivalents (IEs). Total number of IE by the standard method of dithizone staining/manual counting was overestimated by about 90% compared with LM/nuclei counting for 12 freshly isolated human islet research preparations. Nuclei counting combined with islet volume fraction measurements from LM is a novel method for achieving accurate islet enumeration.National Institutes of Health (U.S.) (Grant NCRR ICR U4Z 16606)National Institutes of Health (U.S.) (Grant R01-DK063108-01A1)National Institutes of Health (U.S.) (Grant NCRR ICR U42 RR0023244-01)Joslin Diabetes and Endocrinology Research Center (Grant DK36836)Diabetes Research & Wellness FoundationJuvenile Diabetes Research Foundation International (Islet Transplantation, Harvard Medical School

Comments on "Economic policy for the European Community - the way forward". Selection of comments prepared for a Kiel Symposium on the report of the Group of Rome

Table of Contents: Herbert Giersch, Gottfried Haberler, Jan Tumlir, Juergen B. Donges, Bela Balassa, Europe's Role in the World Economy; Fritz Machlup, Johann Schollhorn, Norbert Walter Pascal Salin, Roland Vaubel, Roads to Monetary Union; Willi Albers, Fritz Neumark, Carl S. Shoup, Dieter Biehl, Fiscal Harmonization; Dieter Biehl, Bela Balassa, Claus Noe, Sebastian Schnyder, The Scope of a Common Regional Policy; Adolf Weber, Tim Josling, New Approaches to Structural Policy? Reforming the Common Agricultural Policy; Gerhard Prosi, Gerhard Fels, Klaus Stegemann, New Approaches to Structural Policy? Industrial Policy, Competition and Social Progres