bluuebunny/crossref_metadata_2025_split huggingface dataset:
Statische und kinetische Instabilitäten bei Bauwerken
Authors: Rosemeier Gustav‐Erich 
Published: August 2010

AbstractIn der Bautechnik treten oft, z. B. bei windbelasteten oder meerestechnischen Konstruktionen, statische oder dynamische Instabilitäten auf – manchmal auch ein Zusammenwirken (Interaktion) beider Mechanismen, wobei die Knick‐ oder Beuleigenformen durchaus verschieden von den entsprechenden Schwingungseigenformen sein können. Es soll dargestellt werden, wann die Stabilitätsuntersuchungen der Strukturen statisch durchgeführt werden dürfen und in welcher Form sich die Ergebnisse bei einer zusätzlichen dynamischen Belastung verändern.Static and dynamic instabilities of structures. In structural design e. g. under wind loads or offshore structures we often have static or dynamic instabilities sometimes also an interaction of both mechanisms, where the buckling modes may be different from the vibration modes. We want to recognize, whether the investigations may be static and how the results may alter by dynamic loads.
Bemessung von Stahlbauten für Anprall‐ und Explosionslasten
Authors: Gündel Max , Hauke Bernhard , Hoffmeister Benno , Feldmann Markus 
Published: August 2010

AbstractDie zunehmende Gefahr von Anschlägen und Industrieunfällen haben zu neuen Anforderungen an die Auslegung und Bemessung von Bauwerken geführt. Diesen neuen Anforderungen wird derzeit in Normen jedoch nur unzureichend Rechnung getragen. Insbesondere für Bauwerke in Stahl‐ und Verbundbauweise führen die gegenwärtig üblichen Auslegungskonzepte nicht zu wirtschaftlichen Bemessungen. Das bauforumstahl hat daher in Zusammenarbeit mit dem Institut für Stahlbau der RWTH Aachen und HOCHTIEF Construction AG einen Bemessungsleitfaden für Anprall‐ und Explosionslasten erarbeitet, mit dem die Möglichkeiten des Werkstoffes Stahl wesentlich effizienter ausgenutzt werden können. In diesem Beitrag werden die wesentlichen Elemente dieses Leitfadens vorgestellt, der sowohl eine Bewertung von Entwurfsstrategien für robuste Bauwerke enthält, als auch ein Bemessungskonzept zur Auslegung von Stahlbauten gegen spezifische kurzzeit‐dynamische Einwirkungen bereitstellt.Design of steel structures against impact and blast loads. The increasing threat of terroristic attacks as well as industrial hazards have led to new demands for the conception and design of buildings. Current standards, however, do not provide sufficient guidance to cope with these new requirements. Particularly for steel and composite structures there is a lack of appropriate and therefore economic design concepts. Hence, bauforumstahl in cooperation with the Institute for Steel Structures at RWTH Aachen University and HOCHTIEF Construction AG has published a new design guide to exploit the capabilities of steel more efficiently. This paper presents the main aspects of this design guide. It includes the assessment of strategies for robust structures and a concept to design steel structures against specific high dynamic loads.
Robuste Stahlbauten bei Brandbelastungen
Authors: Zanon Riccardo , May Marc , Cajot Louis‐Guy , Girkes Hans‐Werner 
Published: August 2010

AbstractIn diesem Aufsatz werden die Aspekte des baulichen Brandschutzes vorgestellt, bei denen die Robustheit der Tragkonstruktion eine zentrale Rolle spielt. Erläutert wird das Konzept des kontrollierten Einsturzverhaltens bei eingeschossigen Gebäuden. Außerdem wird die Robustheit von mehrgeschossigen Gebäuden diskutiert und exemplarisch an drei Beispielen vorgestellt.Robustness of steel constructions under fire load.In this article some applications of fire safety engineering are presented, where the concept of structural robustness plays a major role. First the collapse mode analysis of single‐storey buildings is explained and its application to industrial halls. Then the robustness in multi‐storey buildings is briefly discussed where the examples of local collapse of beam, column and wind bracing are presented.
Plasma Jet Machining
Authors: Arnold Thomas , Boehm Georg , Eichentopf Inga‐Maria , Janietz Manuela , Meister Johannes , Schindler Axel 
Published: August 2010

AbstractPlasma Jet Machining (PJM) is a surface figuring technology based on atmospheric plasma assisted chemical etching or deposition, respectively. In both cases a sub‐aperture plasma jet source is used combined with a CNC multi‐axes system for the processing of curved surfaces. It is under development for the surface figuring of a variety of optical materials by IOM for about 15 years. PJM is capable to figure deep aspheric or free‐form substrates with high material removal rate and high spatial resolution. Based on chemical reactions between plasma generated radicals and the surface PJM does not introduce any damage to the processed surface and sub‐surface region in contrast to abrasive techniques. Deterministic deposition of SiOx layers and subsequent proportional transfer using ion beams or polishing is another plasma jet based technique for surface figuring that extends the range of machinable materials. The article gives an overview on the current state of PJM development in IOM and shows examples of its application.
Zugkraft‐Lastenträger für Vakuumisolation
Authors: Schatz Viktor 
Published: August 2010

AbstractEin lang gehegter Wunsch vieler Forscher und Entwickler von Abstandhaltern für gestützte Vakuumanordnungen ist wahr geworden und ein einfach herstellbarer elementarer Zugkraft‐Lastenträger entwickelt worden, der es möglich macht, mittels auf Zuglast beanspruchter Kraftübertragungselemente die auf beabstandete Wandungen wirkende Druckdifferenzkräfte zu übertragen. Dadurch sind konduktive Wärmeleitwerte bis zu 1E‐6 W/mK und darunter erreichbar. Die Zugkraft‐Lastenträger erlauben ferner eine einfache Unterbringung unbelasteter Strahlungsschildmittel im evakuierten Hohlraum. Außerdem verfügen diese Zugkraft‐Lastenträger über verbesserte Evakuierbarkeit und weisen große Reserven für konstruktive und stoffliche Anpassungen in Anwendungen auf. Es werden insbesondere wärmebrückenfreie evakuierbare Systemanordnungen realisierbar, aber auch randversiegelte VIP‐Platten profitieren durch erreichbare Leistungssteigerung und Kostensenkung.
Prospects for decadal climate prediction
Authors: Keenlyside Noel S. , Ba Jin 
Published: August 2010

AbstractDuring the last decade, global surface temperatures did not increase as rapidly as in the preceding decades. Although relatively small compared to the observed centennial scale global warming, it has renewed interest in understanding and even predicting climate on time scales of decades, and sparked a community initiative on near‐term prediction that will feature in the fifth intergovernmental panel on climate change assessment report. Decadal prediction, however, is in its infancy, with only a few publications existing. This article has three aims. The first is to make the case for decadal prediction. Decadal fluctuations in global climate similar to that of recent decades were observed during the past century. Associated with large regional changes in precipitation and climate extremes, they are of socioeconomic importance. Climate models, which capture some aspects of observed decadal variability, indicate that such variations might be partly predictable. The second aim is to describe the major challenges to skilful decadal climate prediction. One is poor understanding of mechanisms of decadal climate variability, with climate models showing little agreement. Sparse observations in the past, particularly in the ocean, are also a limiting factor to developing and testing of initialization and prediction systems. The third aim is to stress that despite promising initial results, decadal prediction is in a highly experimental stage, and care is needed in interpreting results and utilizing data from such experiments. In the long‐term, decadal prediction has the potential to improve models, reduce uncertainties in climate change projections, and be of socioeconomic benefit. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Climate Models and Modeling > Earth System Models
Climate Models and Modeling > Knowledge Generation with Models
Location‐aided medium access control for low data rate UWB wireless sensor networks
Authors: Karapistoli Eirini , Gragopoulos Ioannis , Tsetsinas Ioannis , Pavlidou Fotini‐Niovi 
Published: August 2010

ABSTRACTThis paper presents a distributed medium access control (MAC) protocol for low data rate ultra‐wideband (UWB) wireless sensor networks (WSNs), named LA‐MAC. Current MAC proposal is closely coupled to the IEEE 802.15.4a physical layer and it is based on its Impulse‐Radio (IR) paradigm. LA‐MAC protocol amplifies its admission control mechanism with location‐awareness, by exploiting the ranging capability of the UWB signals. The above property leads to accurate interference predictions and blocking assessments that each node in the network can perform locally, limiting at the same time the actions needed to be performed towards the admission phase. LA‐MAC is evaluated through extensive simulations, showing a significant improvement in many critical parameters, such as throughput, admission ratio, energy consumption, and delay, under different traffic load conditions. Copyright © 2010 John Wiley & Sons, Ltd.
Characterization of the unsteady flow in the nacelle region of a modern wind turbine
Authors: Zahle Frederik , Sørensen Niels N. 
Published: August 2010

AbstractA three‐dimensional Navier–Stokes solver has been used to investigate the flow in the nacelle region of a wind turbine where anemometers are typically placed to measure the flow speed and the turbine yaw angle. A 500 kW turbine was modelled with rotor and nacelle geometry in order to capture the complex separated flow in the blade root region of the rotor. A number of steady state and unsteady simulations were carried out for wind speeds ranging from 6 m s−1 to 16 m s−1 as well as two yaw and tilt angles. The flow in the nacelle region was found to be highly unsteady, dominated by unsteady vortex shedding from the cylindrical part of the blades, which interacted with the root vortices from each blade, generating high‐velocity gradients. As a consequence, the nacelle wind speed and the nacelle flow angle were found to vary significantly with the height above the nacelle surface. The nacelle anemometry showed significant dependence on both yaw and tilt angles with yaw errors of up to 10 degrees when operating in a tilted inflow. Copyright © 2010 John Wiley & Sons, Ltd.
Adaptive post‐processing of short‐term wind forecasts for energy applications
Authors: Sweeney C. , Lynch P. 
Published: August 2010

AbstractWe present a new method of reducing the error in predicted wind speed, thus enabling better management of wind energy facilities. A numerical weather prediction model, COSMO, was used to produce 48 h forecast data every day in 2008 at horizontal resolutions of 10 and 3 km. A new adaptive statistical method was applied to the model output to improve the forecast skill. The method applied corrective weights to a set of forecasts generated using several post‐processing methods. The weights were calculated based on the recent skill of the different forecasts. The resulting forecast data were compared with observed data, and skill scores were calculated to allow comparison between different post‐processing methods. The total root mean square error performance of the composite forecast is superior to that of any of the individual methods. Copyright © 2010 John Wiley & Sons, Ltd.
Signaling pathways that control cell migration: models and analysis
Authors: Welf Erik S. , Haugh Jason M. 
Published: August 2010

AbstractDissecting the intracellular signaling mechanisms that govern the movement of eukaryotic cells presents a major challenge, not only because of the large number of molecular players involved, but even more so because of the dynamic nature of their regulation by both biochemical and mechanical interactions. Computational modeling and analysis have emerged as useful tools for understanding how the physical properties of cells and their microenvironment are coupled with certain biochemical pathways to actuate and control cell motility. In this focused review, we highlight some of the more recent applications of quantitative modeling and analysis in the field of cell migration. Both in modeling and experiment, it has been prudent to follow a reductionist approach in order to characterize what are arguably the principal modules: spatial polarization of signaling pathways, regulation of the actin cytoskeleton, and dynamics of focal adhesions. While it is important that we ‘cut our teeth’ on these subsystems, focusing on the details of certain aspects while ignoring or coarse‐graining others, it is clear that the challenge ahead will be to characterize the couplings between them in an integrated framework. WIREs Syst Biol Med 2011 3 183–190 DOI: 10.1002/wsbm.110.This article is categorized under:

Analytical and Computational Methods > Analytical Methods
Models of Systems Properties and Processes > Cellular Models
Biological Mechanisms > Cell Signaling
Diaminouronium Nitriminotetrazolates – Thermally Stable Explosives
Authors: Fischer Niko , Klapötke Thomas M. , Piercey Davin , Scheutzow Susanne , Stierstorfer Jörg 
Published: August 2010

AbstractDiaminouronium 5‐nitriminotetrazolate (1) and diaminouronium 1‐methyl‐5‐nitrimino‐tetrazolate (2) were synthesized by the reaction of diaminourea with 5‐nitriminotetrazole (3) and 1‐methyl‐5‐nitriminotetrazole (4), respectively. The energetic compounds 1 and 2 were fully characterized by single‐crystal X‐ray diffraction, NMR spectroscopy, IR‐ and Raman spectroscopy as well as DSC measurements. The sensitivities towards impact, friction and electrical discharge were determined. Several detonation parameters (e.g. heat of explosion, detonation velocity) were computed by the EXPLO5 computer code based on calculated (CBS‐4M) heats of formation and X‐ray densities. In addition, the detonation velocity of 1 was experimentally determined and compared to the computed values.
Outcomes of Staple Fixation of Mesh Versus Nonfixation in Laparoscopic Total Extraperitoneal Inguinal Repair: A Meta‐Analysis of Randomized Controlled Trials
Authors: Tam Ka‐Wai , Liang Hung‐Hua , Chai Chiah‐Yang 
Published: August 2010

AbstractBackgroundStaple fixation of mesh during laparoscopic total extraperitoneal (TEP) inguinal repair is thought to be necessary to prevent recurrence. However, mesh fixation may increase surgical complications and pain. Therefore, a meta‐analysis of randomized controlled trials (RCTs) was conducted to compare the outcomes of nonfixation with fixation of mesh by metal tacks during TEP inguinal hernia repair.MethodsThe meta‐analysis was conducted according to the Quality of Reporting of Meta‐analyses (QUOROM) standards. The inclusion criteria were RCTs comparing stapled with unstapled mesh in TEP inguinal hernia repair. The primary outcome was incidence of recurrence, secondary outcomes were operative duration, postoperative pain score, number of analgesics consumed, in‐hospital stay, time to return to normal activity, cost, and complications.ResultsSix trials were included with a total number of 932 patients (1086 hernias): the mesh was fixed in 463 (540 hernias) patients and not fixed in 469 (546 hernias). We found no difference between groups in the incidence of recurrence (OR = 2.01, 95% CI: 0.37–11.02), complications (OR = 0.73, 95% CI: 0.51–1.05), postoperative pain score [day 1 (p = 0.19), day 7 (p = 0.18) and month 1 (p = 0.47)] and number of analgesics consumed (WMD of −1.20, 95% CI: −3.08 to 0.68). The mean operative time (WMD of −3.86, 95% CI: −7.45 to −0.26) and hospital stay (WMD of −0.34, 95% CI: −0.50 to −0.18) were significantly higher in the mesh fixation group. Moreover, a net cost savings was realized for each hernia repair performed without stapled mesh.ConclusionsElimination of tack fixation of mesh in TEP inguinal hernia repair is associated with decreased operative cost and significantly reduce operative time and in‐hospital stay, but no difference in the risk of hernia recurrence, complications, and postoperative pain. For more detailed evaluation, further well‐structured trials with improved standardization of hernia type, operative technique, and surgeon experience are necessary.
Initial evaluation of a biochemical cystic fibrosis newborn screening by sequential analysis of immunoreactive trypsinogen and pancreatitis‐associated protein (IRT/PAP) as a strategy that does not involve DNA testing in a Northern European population
Authors: Sommerburg Olaf , Lindner Martin , Muckenthaler Martina , Kohlmueller Dirk , Leible Svenja , Feneberg Reinhard , Kulozik Andreas E. , Mall Marcus A. , Hoffmann Georg F. 
Published: August 2010

AbstractBackgroundEthical concerns and disadvantages of newborn screening (NBS) for cystic fibrosis (CF) related to genetic testing have raised controversies and impeded implementation of CF NBS in some countries. In the present study, we used a prospective and sequential immunoreactive trypsinogene (IRT)/pancreatitis‐associated protein (PAP) strategy, with IRT as first and PAP as second tier, and validated this biochemical approach against the widely used IRT/DNA protocol in a population‐based NBS study in southwest Germany.MethodsProspective quantitation of PAP and genetic analysis for the presence of four mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene most prevalent in southwest Germany (F508del, R553X, G551D, G542X) were performed in all newborns with IRT > 99.0th percentile. NBS was rated positive when either PAP was ≥1.0 ng/mL and/or at least one CFTR mutation was detected. In addition, IRT > 99.9th percentile was also considered a positive rating. Positive rating led to referral to a CF centre for testing of sweat Cl− concentration.FindingsOut of 73,759 newborns tested, 98 (0.13%) were positive with IRT/PAP and 56 (0.08%) with IRT/DNA. After sweat testing of 135 CF NBS‐positive infants, 13 were diagnosed with CF. Detection rates were similar for both IRT/PAP and IRT/DNA. One of the 13 diagnosed CF newborns had a PAP concentration <1.0 ng/mL.ConclusionsSequential measurement of IRT/PAP provides good sensitivity and specificity and allows reliable and cost‐effective CF NBS which circumvents the necessity of genetic testing with its inherent ethical problems.
MAD SUBALGEBRAS AND LIE SUBALGEBRAS OF AN ENVELOPING ALGEBRA
Authors: TANG XIN 
Published: August 2010

AbstractLet 𝒰(𝔯(1)) denote the enveloping algebra of the two-dimensional nonabelian Lie algebra 𝔯(1) over a base field 𝕂. We study the maximal abelian ad-nilpotent (mad) associative subalgebras and finite-dimensional Lie subalgebras of 𝒰(𝔯(1)). We first prove that the set of noncentral elements of 𝒰(𝔯(1)) admits the Dixmier partition, 𝒰(𝔯(1))−𝕂=⋃ 5i=1Δi, and establish characterization theorems for elements in Δi, i=1,3,4. Then we determine the elements in Δi, i=1,3 , and describe the eigenvalues for the inner derivation ad Bx,x∈Δi, i=3,4 . We also derive other useful results for elements in Δi, i=2,3,4,5 . As an application, we find all framed mad subalgebras of 𝒰(𝔯(1)) and determine all finite-dimensional nonabelian Lie algebras that can be realized as Lie subalgebras of 𝒰(𝔯(1)) . We also study the realizations of the Lie algebra 𝔯(1) in 𝒰(𝔯(1)) in detail.
Corrigendum: amenability of ultrapowers of Banach algebras
Authors: Daws Matthew 
Published: August 2010

AbstractSome of the results of § 5 of the cited paper are incorrect: in particular, the characterization of when an algebra is ultra-amenable, in terms of a diagonal like construction, is not proved; and Theorem 5.7 is stated wrongly. The rest of the paper is unaffected. We shall show in this corrigendum that Theorem 5.7 can be corrected and that the other results of § 5 are true if the algebra in question has a certain approximation property.
Plant breeding and climate changes
Authors: CECCARELLI S. , GRANDO S. , MAATOUGUI M. , MICHAEL M. , SLASH M. , HAGHPARAST R. , RAHMANIAN M. , TAHERI A. , AL-YASSIN A. , BENBELKACEM A. , LABDI M. , MIMOUN H. , NACHIT M. 
Published: August 2010

SUMMARYClimate change is now unequivocal, particularly in terms of increasing temperature, increasing CO2concentration, widespread melting of snow and ice and rising global average sea level, while the increase in the frequency of drought is very probable but not as certain.However, climate changes are not new and some of them have had dramatic impacts, such as the appearance of leaves about 400 million years ago as a response to a drastic decrease in CO2concentration, the birth of agriculture due to the end of the last ice age about 11 000 years ago and the collapse of civilizations due to the late Holocene droughts between 5000 and 1000 years ago.The climate changes that are occurring at present will have – and are already having – an adverse effect on food production and food quality with the poorest farmers and the poorest countries most at risk. The adverse effect is a consequence of the expected or probable increased frequency of some abiotic stresses such as heat and drought, and of the increased frequency of biotic stresses (pests and diseases). In addition, climate change is also expected to cause losses of biodiversity, mainly in more marginal environments.Plant breeding has addressed both abiotic and biotic stresses. Strategies of adaptation to climate changes may include a more accurate matching of phenology to moisture availability using photoperiod-temperature response, increased access to a suite of varieties with different duration to escape or avoid predictable occurrences of stress at critical periods in crop life cycles, improved water use efficiency and a re-emphasis on population breeding in the form of evolutionary participatory plant breeding to provide a buffer against increasing unpredictability. ICARDA, in collaboration with scientists in Iran, Algeria, Jordan, Eritrea and Morocco, has recently started evolutionary participatory programmes for barley and durum wheat. These measures will go hand in hand with breeding for resistance to biotic stresses and with an efficient system of variety delivery to farmers.
A STATE-LEVEL ANALYSIS OF LIFE EXPECTANCY IN MEXICO (1990–2006)
Authors: PELÁEZ OSCAR , GUIJARRO MARTA , ARIAS MERCEDES 
Published: August 2010

SummaryUsing a methodology similar to that proposed by Barro & Sala-i-Martin (1995), it is found that, in the period 1990–2006, there was strong convergence among state-level life expectancy series, but a distancing in life expectancy in the Mexican Republic compared with more developed countries, especially during the new millennium. The interior convergence had taken place at the expense of the exterior; that is, not so much as a result of an improvement in living conditions in the poorer states, but more due to the low performance of the richer states. The causes of this situation are explained using the concept of ‘epidemiological transition’.
Molinism, open theism, and soteriological luck
Authors: ANDERSON MARK B. 
Published: August 2010

AbstractIt is sometimes claimed by open theists that, on Molinism, God controls who is saved and who is damned and that, as a consequence, God's judgement of us is unjust. While this charge is usually lumped under the problem of evil, it could easily be classified under the problem of soteriological luck. I argue that the open theist is impugned by this latter problem. I then show that the Molinist has a solution to both problems and consider objections to that solution.