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Seismic modelling of tracked-vehicle signals for monitoring and verifi cation

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Applied Geophysics 2021年第2期18卷 252-263,274页

作者： Mathias Pilch jürgen Altmann Experimentelle PhyskⅢ TU Dortmund University44221 DortmundGermany

To better understand characteristics of seismic signals of tracked vehicles measured when passing a sensor line,we numerically modelled force-pulse responses of a layered soil that is similar in its seismic properties to that found at the original measurement *** vertical-force pulses from the road wheels rolling over the track elements are fitted to the measured ***-pulse seismic waves vary with distance due to diff erent wave types,refl ections at layer boundaries,vehicle velocity and relative position of the left and right track *** are computed by a modelling program and superposed at sensor positions with the appropriate slant distance and time shift for each track *** sum signals are in qualitative agreement with those from the original ***,they are several magnitudes weaker and much ***,higher frequencies are damped much less at larger *** to the large variability of the sum signals,recognition of tracked-vehicle types exclusively through their seismic signals seems diffi cult.

关键词： Seismic modelling seismic classification tracked vehicles monitoring verifi cation

Reply to the note by Li Piani et al.

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Defence Technology（防务技术） 2024年第1期31卷 603-606页

作者： T.Li Piani j.Weerheijm L.j.Sluys TU Delft Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands NLDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of *** opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj P.Darłak j.j.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθ<90°in<1 s),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Effect of Intrauterine Laser Therapy at the IVF Success Rate on Infertile Patients with a History of IVF Failure: A Pilot Non-Blinded Study

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Advances in Sexual Medicine 2024年第3期14卷 21-30页

作者： Fateme Hoseinzade Hatav Tehrani Shahriyar Mirshams Yasaman Zandi Mehran Michael hans Weber Department of Physical Medicine and Rehabilitation Isfahan University of Medical Sciences Isfahan Iran Department of Obstetrics and Gynecology Isfahan University of Medical Sciences Isfahan Iran Department of Physical Medicine and Rehabilitation Novin Comprehensive Physical Medicine Center Isfahan Iran Biomedical Engineering Center Dubai UAE International Society of Medical LASER Applications Lauenfoerde Germany

Backgrounds: While there’s developing proof aimed toward improving embryo implantation thru a focal point on great development, restrained studies have been performed on enhancing endometrial receptivity. Intrauterine Laser Therapy (LT) can be powerful in selling endometrial cell proliferation, therefore enhancing the achievement of assisted reproductive techniques (ART). The contemporary look at aimed to research the effectiveness of effective intrauterine lasers in growing endometrial thickness and the achievement of being pregnant rate. Materials and Methods: In the current clinical randomized trial (RTC) study, the infertile women (20 - 42 years old) referred to the infertility clinic in 2023-2024 who were candidates for IVF treatment with recurrent implantation failure (RIF) history were included. The patients were divided into two main groups: the intervention group;low level laser therapy (LLLT) after hormone administration) (n = 52) and the control group (hormone administration without LT) (n = 52). The IVF success rate and change in endometrial thickness before and after the LT were compared in groups. Results: There was a significant difference between groups (p Conclusion: It appears that the incorporation of Intrauterine LT in the realm of infertility could significantly impact as a novel supplementary treatment in improving endometrial receptivity and pregnancy rate.

关键词： Infertility IVF Implementation Intrauterine Low Level Laser Therapy

Multi-Product Expansion with Suzuki’s Method: Generalization

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Numerical Mathematics(Theory,Methods and Applications) 2011年第1期4卷 68-91页

作者： jürgen Geiser Department of Mathematics Humboldt University of BerlinUnter den Linden 6D-10099 BerlinGermany

In this paper we discuss the extension to exponential splitting methods withrespect to time-dependent operators. We concentrate on the Suzuki’s method, whichincorporates ideas to the time-ordered exponential of [3, 11, 12, 34]. We formulate themethods with respect to higher order by using kernels for an extrapolation scheme. Theadvantages include more accurate and less computational intensive schemes to specialtime-dependent harmonic oscillator problems. The benefits of the higher order kernelsare given on different numerical examples.

关键词： Suzuki’s method multiproduct expansion multiplicate and additive splitting schemes exponential splitting

Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun Shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

Solid-state batteries:from 'all-solid' to 'almost-solid'

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National Science Review 2023年第6期10卷 57-59页

作者： Hanyu Huo jürgen janek Institute of Physical Chemistry Justus Liebig University Giessen Center for Materials Research (ZfM) Justus Liebig University Giessen

Lithium-ion batteries (LIBs) have been the undisputed leading technology in electrochemical energy storage since they were commercialized in *** then,the mass manufacturing of LIBs has reached maturity,and we have also seen the realization of high energy density,long cycling stability and low *** technology enabled the huge success of mobile consumer electronics,with its usage in electric vehicles and other advanced *** to the use of organic solvents for the ele ctrolytes,LIBs are sensitive to high temperatures,lose performance at low temperatures and show inherent safety risks with increasing energy density (Fig.1a).As the performance of current LIBs is also limited,next-generation battery technologies are being intensively investigated,especially given the ever-increasing demand for high energy density as well as high power density.

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A noninteracting control strategy for the robust output synchronization of linear heterogeneous networks

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Control Theory and Technology 2014年第3期12卷 234-249页

作者： Saman KHODAVERDIAN jürgen ADAMY Institute of Automatic Control and Mechatronics Control Methods and Robotics Lab Technische Universitt DarmstadtLandgraf-Georg-Str.464283 Darmstadt Germany

This paper deals with the problem of robust output synchronization for heterogeneous multi-agent systems. First, a new synchronization approach is presented to synchronize the outputs of heterogeneous agents. Based on noninteracting control techniques, a method is derived for homogenizing the input-output behavior of every agent. Hence, applying the same reference input signal to every agent leads to synchronization. Furthermore, a strategy for increasing the robustness of the synchronization process against exogenous disturbances is presented, which leads to a structurally constrained optimization problem. However, by a convenient reformulation of the problem, well established tools from robust control theory can be used. Moreover, it is shown that this procedure allows to separate the robustness issue from the synchronization task. The effectiveness of the approach is illustrated by a robust output synchronization example for a heterogeneous aircraft fleet.

关键词： Heterogeneous networks Multi-agent systems Decentralized control Robust synchronization Disturbance rejection Controller constraints and structure

In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

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Particuology 2024年第3期86卷 304-312页

作者： Simon Aβmann Franz j.T.Huber Stefan Will Lehrstuhl für Technische Thermodynamik(LTT) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical Technologies(SAOT) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(TTIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of TTIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution