4,088 research outputs found
Experimentation with Proof Methods for Non-Horn Sets
Two Resolution Proof Strategies Developed by Peterson Are Implemented by Modifying Otter, an Existing Automated Theorem Prover. the Methods, Lock-T Refutation and LNL-T Refutation, Are Generalizations of Unit Refutation and Input Resolution, Respectively, to Non-Horn Sets and Represent Independent, Equivalent but Opposite Ways of Searching. the Algorithms Used Are based on a Corrected Version of the Foundational Work. the Strategies Have Been Tested on Various Non-Horn Challenge Problems from the Tarskian Geometry and the Non-Obvious Problem, with the Results Being in Some Cases Quite Favorable When Compared to Other Resolution Techniques
A field study from the Oderbruch, Germany
The behavior of organophosphates and ethers during riverbank filtration and
groundwater flow was assessed to determine their suitability as organic
tracers. Four sampling campaigns were conducted at the Oderbruch polder,
Germany to establish the presence of chlorinated flame retardants (TCEP, TCPP,
TDCP), non-chlorinated plasticizers (TBEP, TiBP, TnBP), and hydrophilic ethers
(1,4-dioxane, monoglyme, diglyme, triglyme, tetraglyme) in the Oder River,
main drainage ditch, and anoxic aquifer. Selected parameters were measured in
order to determine the hydro-chemical composition of both, river water and
groundwater. The results of the study confirm that organophosphates (OPs) are
more readily attenuated during bank filtration compared to ethers. Both in the
river and the groundwater, TCPP was the most abundant OP with concentrations
in the main drainage ditch ranging between 105 and 958 ng L−1. 1,4-dioxane,
triglyme, and tetraglyme demonstrated persistent behavior during bank
filtration and in the anoxic groundwater. In the drainage ditch concentrations
of 1,4-dioxane, triglyme, and tetraglyme ranged between 1090 and 1467 ng L− 1,
37 and 149 ng L− 1, and 496 and 1403 ng L− 1, respectively. A positive
correlation was found for the inorganic tracer chloride with 1,4-dioxane and
tetraglyme. These results confirm the possible application of these ethers as
environmental organic tracers. Both inorganic and organic compounds showed
temporal variability in the surface- and groundwater. Discharge of the river
water, concentrations of analytes at the time of infiltration and attenuation
were identified as factors influencing the variable amounts of the analytes in
the surface and groundwater. These findings are also of great importance for
the production of drinking water via bank filtration and natural and
artificial groundwater recharge as the physicochemical properties of ethers
create challenges in their removal
Experimental Studies Towards a DC-DC Conversion Powering Scheme for the CMS Silicon Strip Tracker at SLHC
The upgrade of the CMS silicon tracker for the Super-LHC presents many challenges. The distribution of power to the tracker is considered particularly difficult, as the tracker power consumption is expected to be similar to or higher than today, while the operating voltage will decrease and power cables cannot be exchanged or added. The CMS tracker has adopted parallel powering with DC-DC conversion as the baseline solution to the powering problem. In this paper, experimental studies of such a DC-DC conversion powering scheme are presented, including system test measurements with custom DC-DC converters and current strip tracker structures, studies of the detector susceptibility to conductive noise, and simulations of the effect of novel powering schemes on the strip tracker material budget
Improved immunological detection of S pongospora subterranea
The genus Spongospora has two members which are important pathogens of vegetables, S. subterranea f.sp. subterranea (Sss) and S. subterranea f.sp. nasturtii (Ssn). The close taxonomic relationship of these formae speciales is based on similar cystosori morphology. The potato disease powdery scab, caused by Sss, is difficult to control. The key control measure is avoidance, aimed at planting clean seed in clean soil. For the development of routine tests for the presence of the pathogen on tubers and in soil, a monoclonal antibody (MAb) was developed using Sss cystosori as immunogen. It detected less than one Sss cystosorus and recognised Sss material from many parts of the world. No cross-reactions with other Plasmodiophoromycetes including Plasmodiophora brassicae, Polymyxa betae, Polymyxa graminis and different Streptomyces species causing common and netted scab of potatoes were observed. A novel tuber sample test method was developed using a kitchen peeling machine. This detected two tubers with one powdery scab lesion each in a sample including eighteen uninfected tubers. When soil samples spiked with cystosori were tested with the MAb, different Sss infestation levels could be discriminated. Ssn cystosori gave absorbance values in ELISA as high as Sss cystosori, whereas fresh crook roots of watercress containing Ssnzoosporangia and plasmodia or mud from an Ssninfected watercress bed gave low absorbance values or no reaction. The potential of these findings for the development of a disease control management are discusse
First-principles investigation of 180-degree domain walls in BaTiO_3
We present a first-principles study of 180-degree ferroelectric domain walls
in tetragonal barium titanate. The theory is based on an effective Hamiltonian
that has previously been determined from first-principles
ultrasoft-pseudopotential calculations. Statistical properties are investigated
using Monte Carlo simulations. We compute the domain-wall energy, free energy,
and thickness, analyze the behavior of the ferroelectric order parameter in the
interior of the domain wall, and study its spatial fluctuations. An abrupt
reversal of the polarization is found, unlike the gradual rotation typical of
the ferromagnetic case.Comment: Revtex (preprint style, 13 pages) + 3 postscript figures. A version
in two-column article style with embedded figures is available at
http://electron.rutgers.edu/~dhv/preprints/index.html#pad_wal
Timing, Fragmentation of Work and Income Inequality - An Earnings Treatment Effects Approach
Traditional welfare analyses based on money income needs to be broadened by its time dimension. In the course of time the traditional full-time work is diminishing and new labour arrangements are discussed (keyword: flexible labour markets). Our study is contributing to economic well-being by adding insights into particular work effort characteristics - the daily timing of work and its fragmentation - and its resulting income distribution.
With our focus on ‘who is working when within a day with which earnings consequences’ we go beyond traditional labour market analyses with its working time division into aggregated full and part time work, working hours spread across a week and weekend, life time working etc.
Whereas the first part of our study is describing the distribution of timing and fragmentation of daily work time
and its resulting income based on more than 35.000 diaries of the recent German Time Budget Survey 2001/2002, the second part of our study quantifies determinants of arrangement specific earnings functions detecting significant explanatory pattern of what is behind. The economic theory behind is a human capital approach in a market and non-market context, extended by non-market time use, the partner’s working condition, social networking as well as household and regional characteristics. The econometrics use a treatment effects type interdependent estimation of endogenous participation (selection) in a daily working hour pattern (self-selection)and pattern specific earnings function explanation.
The overall result: Individual earnings in Germany are dependent on and significant different with regard to the
daily working hour arrangement capturing timing and fragmentation of work time. Market and non-market
factors are important and significant in explaining earnings
Electronic Scattering Effects in Europium-Based Iron Pnictides
In a comprehensive study, we investigate the electronic scattering effects in
EuFe(AsP) by using Fourier-transform infrared
spectroscopy. In spite of the fact that Eu local moments order around
\,K, the overall optical response is strikingly similar
to the one of the well-known Ba-122 pnictides. The main difference lies within
the suppression of the lower spin-density-wave gap feature. By analysing our
spectra with a multi-component model, we find that the high-energy feature
around 0.7\,eV -- often associated with Hund's rule coupling -- is highly
sensitive to the spin-density-wave ordering, this further confirms its direct
relationship to the dynamics of itinerant carriers. The same model is also used
to investigate the in-plane anisotropy of magnetically detwinned
EuFeAs in the antiferromagnetically ordered state, yielding a
higher Drude weight and lower scattering rate along the crystallographic
-axis. Finally, we analyse the development of the room temperature spectra
with isovalent phosphor substitution and highlight changes in the scattering
rate of hole-like carriers induced by a Lifshitz transition
The Necessity of Inclusive Education for the Renewal of Governance Concepts in Education: Germany and Luxembourg Compared
Die hohe und gestiegene Bedeutung inklusiver Bildung – für Individuen und Gesellschaften gleichermaßen – wird global, national, regional und lokal von verschiedensten Akteur*innen hervorgehoben sowie zunehmend auch wissenschaftlich multidisziplinär diskutiert. Fragen der Steuerung, der Governance, hingegen, sind bisher im deutschsprachigen Raum nur wenig systematisch oder umfassend analysiert worden, obwohl mehrere Wissenschaftsdisziplinen sich zunehmend mit diesen Fragen auseinandersetzen. Während politikwissenschaftliche Analysen die Machtstrukturen, Pfadabhängigkeiten und Entscheidungsprozesse fokussieren haben soziologische Analysen die globale Diffusion von Diskursen und Normen sowie systembedingte Komplexitäten und Umsetzungsschwierigkeiten vielfältiger Reformen verdeutlicht. Die Erziehungswissenschaft, nicht nur in der deutsch-sprachigen Welt, hat sich lange Zeit schwer getan, sich eindeutig zu den brisanten bildungs- als auch sozialpolitischen Fragen der inklusiven Bildung – auch die zentrale Frage der Governance – zu positionieren, weil es das fundamentale Verhältnis von Allgemeiner und Sonderpädagogik hinterfragt sowie in letzter Konsequenz die Transformation des gegliederten und hochgradig selektiven Bildungswesen verlangt. Dieser Band beleuchtet eben dieses Spannungsverhältnis aus verschiedenen Perspektiven; in diesem Beitrag wird deshalb versucht, verschiedene Dimensionen der Governance auf der Forschungsagenda zu platzieren, wie auch in zwei konkreten Fällen – Deutschland und Luxemburg – zu vertiefen
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