22 research outputs found
Contactless 2-dimensional laser sensor for 3-dimensional wire position and tension measurements
We have developed a contact-free 2-dimensional laser sensor with which the
position of wires can be measured in 3 dimensions with an accuracy of better
than 10 micrometer and with which the tension of the wires can be determined
with an accuracy of 0.04 N. These measurements can be made from a distance of
15 cm. The sensor consists of commercially available laser pointers, lenses,
color filters and photodiodes. In our application we have used this laser
sensor together with an automated 3 dimensional coordinate table. For a single
position measurement, the laser sensor is moved by the 3-dimensional coordinate
table in a plane and determines the coordinates at which the wires intersect
with this plane. The position of the plane itself (the third coordinate) is
given by the third axis of the measurement table which is perpendicular to this
plane. The control and readout of the table and the readout of the laser sensor
were realized with LabVIEW. The precision of the position measurement in the
plane was determined with wires of 0.2 mm and 0.3 mm diameter. We use the
sensor for the quality assurance of the wire electrode modules for the KATRIN
neutrino mass experiment. We expect that the precision is at least comparable
or better if the wires are thinner. Such a device could be well suited for the
measurement of wire chamber geometries even with more than one wire layer.Comment: 15 pages, 8 figure
Проблемы энергетического развития и экономической безопасности: альтернативная или традиционная энергетика
В данной статье рассматриваются причины, по которым мировая экономика не может перейти на альтернативную энергетику. В России переход на альтернативную энергетику приведет не только к социальной и экономической нестабильности, но и к угрозе национальной безопасности страны с напряженными международными отношениями. Такой фактор как развитие традиционного топливно-экономического комплекса поможет обеспечить экономическую безопасность России
Observation of the hyperfine transition in lithium-like Bismuth : Towards a test of QED in strong magnetic fields
We performed a laser spectroscopic determination of the hyperfine
splitting (HFS) of Li-like and repeated the measurement
of the HFS of H-like . Both ion species were
subsequently stored in the Experimental Storage Ring at the GSI
Helmholtzzentrum f\"ur Schwerionenforschung Darmstadt and cooled with an
electron cooler at a velocity of . Pulsed laser excitation of
the hyperfine-transition was performed in anticollinear and collinear
geometry for and , respectively, and
observed by fluorescence detection. We obtain for , different from the literature
value, and for .
These values provide experimental evidence that a specific difference between
the two splitting energies can be used to test QED calculations in the
strongest static magnetic fields available in the laboratory independent of
nuclear structure effects. The experimental result is in excellent agreement
with the theoretical prediction and confirms the sum of the Dirac term and the
relativistic interelectronic-interaction correction at a level of 0.5%
confirming the importance of accounting for the Breit interaction.Comment: 5 pages, 2 figure
Internal Transcribed Spacer 2 (nu ITS2 rRNA) Sequence-Structure Phylogenetics: Towards an Automated Reconstruction of the Green Algal Tree of Life
L). Some have advocated the use of the nuclear-encoded, internal transcribed spacer two (ITS2) as an alternative to the traditional chloroplast markers. However, the ITS2 is broadly perceived to be insufficiently conserved or to be confounded by introgression or biparental inheritance patterns, precluding its broad use in phylogenetic reconstruction or as a DNA barcode. A growing body of evidence has shown that simultaneous analysis of nucleotide data with secondary structure information can overcome at least some of the limitations of ITS2. The goal of this investigation was to assess the feasibility of an automated, sequence-structure approach for analysis of IT2 data from a large sampling of phylum Chlorophyta.Sequences and secondary structures from 591 chlorophycean, 741 trebouxiophycean and 938 ulvophycean algae, all obtained from the ITS2 Database, were aligned using a sequence structure-specific scoring matrix. Phylogenetic relationships were reconstructed by Profile Neighbor-Joining coupled with a sequence structure-specific, general time reversible substitution model. Results from analyses of the ITS2 data were robust at multiple nodes and showed considerable congruence with results from published phylogenetic analyses.Our observations on the power of automated, sequence-structure analyses of ITS2 to reconstruct phylum-level phylogenies of the green algae validate this approach to assessing diversity for large sets of chlorophytan taxa. Moreover, our results indicate that objections to the use of ITS2 for DNA barcoding should be weighed against the utility of an automated, data analysis approach with demonstrated power to reconstruct evolutionary patterns for highly divergent lineages
An algorithmic module toolkit to support quality management for building performance
Data from building automation systems is so far used for the operation of building systems and components only. The following work shows how this data can be used to enhance the building’s performance by strategically detecting potential sources for building optimization. With this method, faults and optimization potentials of the building operation can be detected; thus, the quality gap regarding efficiency and comfort aspects between design and operation can then be reduced. Furthermore, the intelligent use of data enables the realization of economic savings to support facility management with regards to increasingly complex HVAC systems. Effective quality management – rapid, transparent and cost effective – is carried out with the aid of digital methods, which are already state of the art in other industries
Allocation of carbon dioxide emissions to the by-products of combined heat and power plants: A methodological guidance
Gefördert durch den Publikationsfonds der Universität Kasse
Allocation of carbon dioxide emissions to the by-products of combined heat and power plants: A methodological guidance
Cogeneration has higher efficiency than separate heat and power generation. Since both are generated in a single process, it is necessary to allocate the emissions to by-products for comparing their environmental performance. Numerous methods exist resulting in very different allocations. There is no consensus regarding the method choice. The main objective of this article is the development and implementation of an evaluation scheme allowing the choice of an appropriate method for specific applications. This scheme consists of nine criteria in the categories “Applicability”, “Environmental relevance”, and “Systematic approach” allowing a rating. The Finnish method performs best for a standard use case resulting in emission factors of 322 g CO2 / kWhel and 192 g CO2 / kWhth. Both are associated with less emissions per unit then the electricity and district heating mix of Germany in 2020 that were 375 g CO2 / kWhel and 270 g CO2 / kWhth. Therefore, cogeneration electricity and heat could contribute to climate protection in the short- to mid-term. The implementation of two sensitivity analyses shows that the location and country-specific emission factors can have a great influence on the results and the contribution to climate protection. Depending on use case and individual importance of certain criteria the Energy, the Exergy or the Greenhouse Gas method can be preferable. Each scored with one point less than the Finnish method. In contrast to existing publications, this study supports decision-makers in transparently selecting an appropriate allocation method when assessing the products of cogeneration by considering different criteria