TUHH Open Research
Hilfe
  • Log In
    or
    New user? Click here to register.Have you forgotten your password?
  • English
  • Deutsch
  • Communities & Collections
  • Publications
  • Research Data
  • People
  • Institutions
  • Projects
  • Statistics
  1. Home
  2. Browse by Title

Browsing by Title

Now showing1 - 20 of 15144
Results Per Page
Sort Options
  • Publication
    [1,2]-Domination in generalized Petersen graphs
    (2019-10-01)
    Beggas, Fairouz 
    ;
    Turau, Volker 
    ;
    Haddad, Mohammed 
    ;
    Kheddouci, Hamamache 
    A vertex subset S of a graph G = (V,E) is a [1, 2]-dominating set if each vertex of V is adjacent to either one or two vertices in S. The minimum cardinality of a [1, 2]-dominating set of G, denoted by γ[1,2](G), is called the [1, 2]-domination number of G. In this paper, the [1, 2]-domination and the [1, 2]-total domination numbers of the generalized Petersen graphs P(n, 2) are determined.
    Publication Type: Journal Article
    Publisher DOI:10.1142/S1793830919500587
      164
  • Publication
    1,3-propanediol and polytrimethyleneterephthalate
    (2019)
    Tjahjasari, Donna 
    ;
    Kaeding, Thomas 
    ;
    Zeng, An-Ping orcid-logo
    1,3-Propanediol (PDO) is an appealing chemical for use in the production of new types of polymers such as polytrimethyleneterephthalate (PTT). In particular, the recent successful replacement of chemical routes for PDO production by a biological process makes PDO a prominent green chemical from renewable materials. This chapter first briefly describes the properties, uses, and production methods of PDO and PTT. Emphases are then laid on describing the biotechnological production of PDO in more detail, ranging from substrates, microorganisms, metabolic pathway engineering to fermentation processes and downstream processing. The different fermentation processes and downstream processing methods are compared, in terms of both technology and economy. It is evident that not only the glucose-based bioprocess, but also the bioconversion of glycerol into PDO is technologically and economically sound. Especially, a new biorefinery concept using a microbial community for glycerol bioconversion into PDO and bioenergy is illustrated which is attractive due to its simplicity and very low production costs. Perspectives and further research needs to this end are discussed.
    Publication Type: Book Part
    Publisher DOI:10.1016/B978-0-444-64046-8.00164-6
      235
  • Publication
    1-D simulation of backward-wave and Pi-mode oscillations in helix traveling-wave tubes
    (2021-04-29)
    Hägermann, Moritz orcid-logo
    ;
    Birtel, Philip 
    ;
    Jacob, Arne 
    Publication Type: Conference Paper
      56
  • Publication
    10 dB emission suppression in a structured low index medium
    (2023-04)
    Saha, Soumyadeep 
    ;
    Mustafa, Meraj E 
    ;
    Eich, Manfred 
    ;
    Petrov, Alexander orcid-logo
    Significant suppression of radiation in3Dstructured media with small refractive indices of 1.4-1.6, such as glass or polymers, is a desirable feature yet to be obtained.We present here quasiperiodic3Dstructures with a homogeneous distribution ofBragg peaks on a sphere in reciprocal space obtained by an overlap of multiple gratings. Simulations on 3D structures revealed a limitation of emission suppression contrasting from theoretical predictions. The effect of number of gratings and refractive index contrast on the obtained suppression is investigated.We demonstrate an almost refractive index independent-10 dB suppression of emission for a refractive index as low as 1.30.
    Publication Type: Journal Article
    Publisher DOI:10.1364/JOSAB.477576
      32
  • Publication
    100 GHz reflectometer for sensitivity analysis of MEMS sensors comprising an intermediate frequency Six-port receiver
    (2015-01)
    Linz, Sarah 
    ;
    Oesterle, Florian 
    ;
    Talai, Armin 
    ;
    Lindner, Stefan 
    ;
    Mann, Sebastian 
    ;
    Barbon, Francesco 
    ;
    Weigel, Robert 
    ;
    Kölpin, Alexander orcid-logo
    Due to the growing market for Micro Electro Mechanical Systems (MEMS), especially for the application in mobile electronic devices like cameras, phones or tablet computers, cost and time efficient test and evaluation systems are required for the production process. This work presents a novel measurement setup for MEMS microphones, that allows an inline, contactless evaluation of the microphones' mechanical sensitivity at an early stage of the manufacturing process. A heterodyne receiver with a Six-port demodulator is deployed for displacement detection with micrometer resolution. Since the Six-port demodulator allows very high sampling rates, only limited by the analog-to-digital converter, short measurement times can be achieved.
    Publication Type: Conference Paper
    Publisher DOI:10.1109/WISNET.2015.7127403
      152
  • Publication
    101 discrete algebraic structures - stack exchange
    (2017)
    Zimmermann, Karl-Heinz 
    The problems treated in this report are from the website ”Mathematics Stack Exchange”. This is a question-and-answer website, where questions, answers, and users are subject to a reputation award process. The questions are strongly related to the two-hour lecture ”Discrete Algebraic Structures” including a two-hour lab held for first-year Bachelor students of Computer Science at the Hamburg University of Technology. The problems encountered should give some deeper insight into the field. Enjoy the read!
    Publication Type: Technical Report
      755  737
  • Publication
    110th Anniversary: Solvent Exchange in the Processing of Biopolymer Aerogels: Current Status and Open Questions
    (2019-10-09)
    Gurikov, Pavel 
    ;
    Subrahmanyam, Raman 
    ;
    Griffin, Justin S. 
    ;
    Steiner, Stephen A. 
    ;
    Smirnova, Irina orcid-logo
    In the past decade, the uses and applications of aerogels have garnered significant scientific curiosity in the aerogel community. Furthermore, renewed focus on the supercritical CO2 drying methodology of aerogels has expanded the material scope to several biopolymer systems that now offer new avenues for material, property, and application exploration. However, the principal challenge of the aerogel community is to balance the complexity and costs of aerogel processing with the enhanced material properties that the final aerogel presents. In the case of biopolymer aerogel processing by supercritical CO2 drying, an intermediate solvent exchange step is required in most cases as the biopolymers are gelled in water (hydrogels) and the supercritical CO2 drying cannot commence due to the miscibility gap in the water/CO2 system. Very limited information is available on exchanging water in a gel with organic solvents. The aim of this commentary paper is to introduce aerogel researchers to several aspects of the gel shrinkage during aerogel processing and invite the reader to address the open questions related to the basis for solvent selection in aerogel synthesis.
    Publication Type: Journal Article
    Publisher DOI:10.1021/acs.iecr.9b02967
      157
  • Publication
    122 GHz low-cost substrate integrated waveguide based leaky-wave antenna design
    (2019-01)
    Frank, Matthias 
    ;
    Lurz, Fabian 
    ;
    Weigel, Robert 
    ;
    Kölpin, Alexander orcid-logo
    This paper describes the design and characterization of three different compact low-cost substrate integrated waveguide (SIW) leaky-wave antennas on a RO4350B substrate. In order to increase the gain of the basic leaky-wave antenna, two different arrays consisting of multiple parallel fed SIW lines are formed. Measurements of both return loss and radiation pattern were performed for all three antenna structures around 122.5GHz and show good agreement with the numerical results. The maximum realized gain has been determined to be slightly above 16dBi.
    Publication Type: Conference Paper
    Publisher DOI:10.1109/RWS.2019.8714239
      91
  • Publication
    140 GHz gyrotron development at KfK Karlsruhe
    (SPIE, 1990-12-01)
    Borie, Edith 
    ;
    Dammertz, Guenter 
    ;
    Dumbrajs, Olgierd 
    ;
    Gantenbein, Gerd 
    ;
    Geist, Andreas René 
    ;
    Hochschild, Gerd 
    ;
    Kuntze, Michael 
    ;
    Liao, Z. 
    ;
    Möbius, Arnold W. 
    ;
    Nickel, Hans-Ulrich 
    ;
    Piosczyk, Bernhard 
    ;
    Thumm, Manfred K. A. 
    ;
    Wenzelburger, Heinz 
    The experimental setup of a gyrotron which operates in the TE0,3 mode is described. The results of measurements with several gyrotron versions at short pulses (0.5 ms) and long pulses (100 ms) are reported. Designs for higher powers (up to 1 MW) using a nonsymmetric volume mode are presented. First experiments will use the TE10,4 mode. A quasioptical convertor for the output mode will be used, either in conjunction with an axial window or, later, with a radial window.
    Publication Type: Conference Paper
    Publisher DOI:10.1117/12.2301566
      197
  • Publication
    15 years of SPALTEN problem solving methodology in product development
    (The Design Society, 2016-08)
    Albers, Albert 
    ;
    Reiß, Nicolas 
    ;
    Bursac, Nikola 
    ;
    Breitschuh, Jan 
    The brain has only limited ability to deal with complex Problems. Therefore, the developer must be supported to supplement his natural problem-solving behaviors. The SPALTEN-Methodology was described by Albers et al. and constantly developed further in the past 15 years. Furthermore, it was applied consistently in projects and education. SPALTEN is a German acronym and means "to split", "to decompose". In this contribution, the results of an extensive empirical study of the use of SPALTEN in the last 15 years is presented. The study consists of a qualitative preliminary study on basic of interviews (n=15) and a quantitative survey using a questionnaire (n=108) and has a focus on the application and the added value for the user. The results show, that SPALTEN is used in practice by over 80 % of former students and PhD-students, who learned the method in their education.
    Publication Type: Conference Paper
      24
  • Publication
    Die 15-Minuten-Stadt : alter Wein in neuen Schläuchen?
    (SRL, 2022-08)
    Werner, Lennard 
    Publication Type: Journal Article
      244
  • Publication
    15. Seminar der LIBER Architecture Group
    (De Gruyter, 2010-05)
    Feldsien-Sudhaus, Inken orcid-logo
    This year the National Library of Spain in Madrid hosted the 15th Seminar of the LIBER Architecture Group from 12th to 17th of April 2010. The innovative offer of tours and speeches as well as the possibility of program exchanges attracted interested participants from every corner of Europe. Of course, subjects such as renovation and extension of existing facilities abounded. This year to enhance more subjects of the day, several talks were directed towards the development of internet services within the library. These new internet technologies present interesting challenges for libraries wishing to implement these new programs. As expected, the Spanish team had organized the meeting in an excellent manner and every aspect of the conference was well thought through.
    Publication Type: Journal Article
    Publisher DOI:10.1515/ABITECH.2010.30.2.100
      1089  827
  • Publication
    1D wave propagation in saturated soils: verification of two-phase MPM
    (2019)
    Chmelnizkij, Alexander 
    ;
    Ceccato, Francesca 
    ;
    Grabe, Jürgen 
    ;
    Simonini, P. 
    Publication Type: Conference Paper
      104
  • Publication
    2-dimensionales, differentielles Grenzschichtberechnungsverfahren nach Cebeci
    (1984)
    Achner, Andreas 
    ;
    Marzi, Jochen 
    2-dimensionales, differentielles Grenzschichtberechnungsverfahren nach Cebeci Beschreibung und Berechnungsbeispiele
    Publication Type: Technical Report
      1636  223
  • Publication
    2-phase dynamic simulation of deep sand compaction to reduce liquefaction
    (Elsevier, 2017)
    Nagula, Sparsha Sinduri 
    ;
    Grabe, Jürgen 
    A numerical model of a shallow foundation resting on sand is set up to simulate the liquefaction of partially saturated sand subjected to a confined transient loading. The foundation is observed to undergo large settlements due to liquefaction of sand. In order to analyze the feasibility of deep vibration compaction in liquefaction mitigation, saturated sand was subjected to compaction and later the same compacted sand with foundation was subjected to a confined transient loading. It was observed that the compaction technique reduced liquefaction drastically, suggesting that deep vibration compaction can be effectively used as a liquefaction mitigation measure.The compaction method includes densification of loose sands by means of shear deformation processes imparted by horizontal vibrations of vibrator probe at the required soil depth. A coupled hypoplastic constitutive model is used to characterize the stress-strain behavior of the saturated sand.
    Publication Type: Journal Article
    Publisher DOI:10.1016/j.proeng.2017.09.277
      318  288Scopus© Citations 4
  • Publication
    20 years of co-creation using case based learning: an integrated approach for teaching innovation and research in product generation engineering
    (Springer, 2018-09)
    Albers, Albert 
    ;
    Bursac, Nikola 
    ;
    Heimicke, Jonas 
    ;
    Walter, Benjamin 
    ;
    Reiß, Nicolas 
    The teaching program IP - Integrated Product Development has been implemented annually with great success for 20 years, which means that this format has gained a high level of acceptance among companies from a wide range of industries. The participating students acquire professional skills in the area of PGE - Product Generation Engineering through the experience of the real development project and by applying activities and methods of product development, combined with a lecture that deals with the most recent cases from the business world. With the aim of bringing the co-creation formats to further student target groups with diverse needs, the format IP was analyzed and a general valid co-creation approach for case-based learning, was characterized by relevant success factors. Based on this, it was possible to transfer the success factors from IP contextual into the breadth (reaching a high number of students) and into the depth (gain of research competences) by means of two further formats.
    Publication Type: Conference Paper
    Publisher DOI:10.1007/978-3-319-73204-6_69
      44
  • Publication
    22. Steinheimer Gespräche – Chemie und Automatisierung
    (Wiley-VCH, 2019-09)
    Lissel, Franziska 
    ;
    Steinberg, Simon 
    Publication Type: Journal Article
    Publisher DOI:10.1002/nadc.20194091624
      96
  • Publication
    24 GHz six-port medical radar for contactless respiration detection and heartbeat monitoring
    (2012-11)
    Vinci, Gabor 
    ;
    Lindner, Stefan 
    ;
    Barbon, Francesco 
    ;
    Hofmann, Sebastian orcid-logo
    ;
    Fischer, Georg 
    ;
    Kissinger, Dietmar 
    ;
    Kölpin, Alexander orcid-logo
    For numerous medical applications it is of primary interest to monitor the breath rate and heartbeat of a patient over time. Especially important is to observe the respiration of a patient over night to detect potential sleep disorders. Furthermore, heartbeat frequency is also a precious information which can help to improve diverse diagnosis procedures. In order to better analyze these vital parameters an innovative contactless respiration detection and heartbeat monitoring technique has been developed. This novel method is based on the six-port interferometric radar and is capable of detecting breath rate as well as heartbeat frequency without applying sensors or electrodes on the patients body.
    Publication Type: Conference Paper
      116
  • Publication
    2D integrating cell for ultra-long optical path on chip
    (OSA, The Optical Society, 2018)
    Petrov, Alexander orcid-logo
    ;
    Fohrmann, Lena Simone 
    ;
    Sommer, Gerrit 
    ;
    Pitruzzello, Giampaolo 
    ;
    Krauss, Thomas F. 
    ;
    Eich, Manfred 
    We introduce a 2D waveguide platform employing an integrating cell approach which enables ultra-long optical propagation paths in a very small geometrical footprint. Effective propagation length of 25 cm is demonstrated.
    Publication Type: Conference Paper
    Publisher DOI:10.1364/IPRSN.2018.ITh1B.8
      180
  • Publication
    2D integrating cell waveguide platform employing ultra-long optical path lengths
    (IEEE, 2017-10-26)
    Fohrmann, Lena Simone 
    ;
    Sommer, Gerrit 
    ;
    Pitruzzello, Giampaolo 
    ;
    Krauss, Thomas F. 
    ;
    Petrov, Alexander orcid-logo
    ;
    Eich, Manfred 
    A 2D integrating cell waveguide platform is presented where ultra-long optical path lengths in a small area are realized by multiple reflections of a guided signal at PhC boundaries. In experiments, path lengths of 25 cm are demonstrated in integrating cells with 1.8 mm radius.
    Publication Type: Conference Paper
    Publisher DOI:10.1109/GROUP4.2017.8082231
      115
  • «
  • 1 (current)
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • ...
  • 758
  • »
TUHH
Weiterführende Links
  • Contact
  • Send Feedback
  • Cookie settings
  • Privacy policy
  • Impress
DSpace Software

Built with DSpace-CRIS software - Extension maintained and optimized by 4Science
Design by effective webwork GmbH

  • Deutsche NationalbibliothekDeutsche Nationalbibliothek
  • ORCiD Member OrganizationORCiD Member Organization
  • DataCiteDataCite
  • Re3DataRe3Data
  • OpenDOAROpenDOAR
  • OpenAireOpenAire
  • BASE Bielefeld Academic Search EngineBASE Bielefeld Academic Search Engine
Feedback