TY  - JOUR
A1  - Köhler, Klemens
T1  - A conflict theory perspective of IT attacks – consequences for IT security education
N2  - Cyberspace is "the environment formed by physical and non-physical components to store, modify, and exchange data using computer networks" (NATO CCDCOE). Beyond that, it is an environment where people interact. IT attacks are hostile, non-cooperative interactions that can be described with conflict theory. Applying conflict theory to IT security leads to different objectives for end-user education, requiring different formats like agency-based competence developing games.
Y1  - 2020
IS  - Preprint
ER  - 
TY  - JOUR
A1  - Jildeh, Zaid B.
A1  - Kirchner, Patrick
A1  - Oberländer, Jan
A1  - Vahidpour, Farnoosh
A1  - Wagner, Patrick H.
A1  - Schöning, Michael Josef
T1  - Development of a package-sterilization process for aseptic filling machines: A numerical approach and validation for surface treatment with hydrogen peroxide
JF  - Sensor and Actuators A: Physical
N2  - Within the present work a sterilization process by a heated gas mixture that contains hydrogen peroxide (H₂O₂) is validated by experiments and numerical modeling techniques. The operational parameters that affect the sterilization efficacy are described alongside the two modes of sterilization: gaseous and condensed H₂O₂. Measurements with a previously developed H₂O₂ gas sensor are carried out to validate the applied H₂O₂ gas concentration during sterilization. We performed microbiological tests at different H₂O₂ gas concentrations by applying an end-point method to carrier strips, which contain different inoculation loads of Geobacillus stearothermophilus spores. The analysis of the sterilization process of a pharmaceutical glass vial is performed by numerical modeling. The numerical model combines heat- and advection-diffusion mass transfer with vapor–pressure equations to predict the location of condensate formation and the concentration of H₂O₂ at the packaging surfaces by changing the gas temperature. For a sterilization process of 0.7 s, a H₂O₂ gas concentration above 4% v/v is required to reach a log-count reduction above six. The numerical results showed the location of H₂O₂ condensate formation, which decreases with increasing sterilant-gas temperature. The model can be transferred to different gas nozzle- and packaging geometries to assure the absence of H₂O₂ residues.
Y1  - 2020
U6  - https://doi.org/10.1016/j.sna.2019.111691
SN  - 0924-4247
VL  - 303
IS  - 111691
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Cosma, Cosmin
A1  - Kessler, Julia
A1  - Gebhardt, Andreas
A1  - Campbell, Ian
A1  - Balc, Nicolae
T1  - Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed
JF  - Materials
N2  - To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250–1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L.
Y1  - 2020
U6  - https://doi.org/10.3390/ma13040905
SN  - 1996-1944
VL  - 13
IS  - 4
SP  - 1
EP  - 18
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Mennicken, Max
A1  - Peter, Sophia K.
A1  - Kaulen, Corinna
A1  - Simon, Ulrich
A1  - Karthäuser, Silvia
T1  - Transport through Redox-Active Ru-Terpyridine Complexes Integrated in Single Nanoparticle Devices
JF  - The Journal of Physical Chemistry C
N2  - Transition metal complexes are electrofunctional molecules due to their high conductivity and their intrinsic switching ability involving a metal-to-ligand charge transfer. Here, a method is presented to contact reliably a few to single redox-active Ru-terpyridine complexes in a CMOS compatible nanodevice and preserve their electrical functionality. Using hybrid materials from 14 nm gold nanoparticles (AuNP) and bis-{4′-[4-(mercaptophenyl)-2,2′:6′,2″-terpyridine]}-ruthenium(II) complexes a device size of 30² nm² inclusive nanoelectrodes is achieved. Moreover, this method bears the opportunity for further downscaling. The Ru-complex AuNP devices show symmetric and asymmetric current versus voltage curves with a hysteretic characteristic in two well separated conductance ranges. By theoretical approximations based on the single-channel Landauer model, the charge transport through the formed double-barrier tunnel junction is thoroughly analyzed and its sensibility to the molecule/metal contact is revealed. It can be verified that tunneling transport through the HOMO is the main transport mechanism while decoherent hopping transport is present to a minor extent.
Y1  - 2020
U6  - https://doi.org/10.1021/acs.jpcc.9b11716
SN  - 1932-7455
VL  - 124
IS  - 8
SP  - 4881
EP  - 4889
PB  - ACS Publications
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Wardoyo, Arinto Y.P.
A1  - Noor, Johan A.E.
A1  - Elbers, Gereon
A1  - Schmitz, Sandra
A1  - Flaig, Sascha T.
A1  - Budianto, Arif
T1  - Characterizing volcanic ash elements from the 2015 eruptions of bromo and raung volcanoes, Indonesia
JF  - Polish Journal of Environmental Studies
N2  - The volcanic eruptions of Mt. Bromo and Mt. Raung in East Java, Indonesia, in 2015 perturbed volcanic materials and affected surface-layer air quality at surrounding locations. During the episodes, the volcanic ash from the eruptions influenced visibility, traffic accidents, flight schedules, and human health. In this research, the volcanic ash particles were collected and characterized by relying on the detail of physical observation. We performed an assessment of the volcanic ash elements to characterize the volcanic ash using two different methods which are aqua regia extracts followed by MP-AES and XRF laboratory test of bulk samples. The analysis results showed that the volcanic ash was mixed of many materials, such as Al, Si, P, K, Ca, Ti, V, Cr, Mn, Fe, Ni, and others. Fe, Si, Ca, and Al were found as the major elements, while the others were the trace elements Ba, Cr, Cu, Mn, P, Mn, Ni, Zn, Sb, Sr, and V with the minor concentrations. XRF analyses showed that Fe dominated the elements of the volcanic ash. The XRF analysis showed that Fe was at 35.40% in Bromo and 43.00% in Raung of the detected elements in bulk material. The results of aqua regia extracts analyzed by MP-AES were 1.80% and 1.70% of Fe element for Bromo and Raung volcanoes, respectively.
Y1  - 2020
U6  - https://doi.org/10.15244/pjoes/99101
SN  - 2083-5906
VL  - 29
IS  - 2
SP  - 1899
EP  - 1907
PB  - HARD
CY  - Olsztyn
ER  - 
TY  - JOUR
A1  - Khayyam, Hamid
A1  - Jamali, Ali
A1  - Bab-Hadiashar, Alireza
A1  - Esch, Thomas
A1  - Ramakrishna, Seeram
A1  - Jalil, Mahdi
A1  - Naebe, Minoo
T1  - A Novel Hybrid Machine Learning Algorithm for Limited and Big Data Modelling with Application in Industry 4.0
JF  - IEEE Access
N2  - To meet the challenges of manufacturing smart products, the manufacturing plants have been radically changed to become smart factories underpinned by industry 4.0 technologies. The transformation is assisted by employment of machine learning techniques that can deal with modeling both big or limited data. This manuscript reviews these concepts and present a case study that demonstrates the use of a novel intelligent hybrid algorithms for Industry 4.0 applications with limited data. In particular, an intelligent algorithm is proposed for robust data modeling of nonlinear systems based on input-output data. In our approach, a novel hybrid data-driven combining the Group-Method of Data-Handling and Singular-Value Decomposition is adapted to find an offline deterministic model combined with Pareto multi-objective optimization to overcome the overfitting issue. An Unscented-Kalman-Filter is also incorporated to update the coefficient of the deterministic model and increase its robustness against data uncertainties. The effectiveness of the proposed method is examined on a set of real industrial measurements.
Y1  - 2020
SN  - 2169-3536
U6  - https://doi.org/10.1109/ACCESS.2020.2999898
SP  - 1
EP  - 12
PB  - IEEE
CY  - New York, NY
ER  - 
TY  - JOUR
A1  - Hailer, Benjamin
A1  - Weber, Tobias
A1  - Neveling, Sebastian
A1  - Dera, Samuel
A1  - Arent, Jan-Christoph
A1  - Middendorf, Peter
T1  - Development of a test device to determine the frictional behavior between honeycomb and prepreg layers under realistic manufacturing conditions
JF  - Journal of Sandwich Structures & Materials
N2  - In the friction tests between honeycomb with film adhesive and prepreg, the relative displacement occurs between the film adhesive and the prepreg. The film adhesive does not shift relative to the honeycomb. This is consistent with the core crush behavior where the honeycomb moves together with the film adhesive, as can be seen in Figure 2(a). The pull-through forces of the friction measurements between honeycomb and prepreg at 1 mm deformation are plotted in Figure 17(a). While the friction at 100°C is similar to the friction at 120°C, it decreases significantly at 130°C and exhibits a minimum at 140°C. At 150°C, the friction rises again slightly and then sharply at 160°C. Since the viscosity of the M18/1 prepreg resin drops significantly before it cures [23], the minimum friction at 140°C could result from a minimum viscosity of the mixture of prepreg resin and film adhesive before the bond subsequently cures. Figure 17(b) shows the mean value curve of the friction measurements at 140°C. The error bars, which represent the standard deviation, reveal the good repeatability of the tests. The force curve is approximately horizontal between 1 mm and 2 mm. The friction then slightly rises. As with interlaminar friction measurements, this could be due to the fact that resin is removed by friction and the proportion of boundary lubrication increases. Figure 18 shows the surfaces after the friction measurement. The honeycomb cell walls are clearly visible in the film adhesive. There are areas where the film adhesive is completely removed and the carrier material of the film adhesive becomes visible. In addition, the viscosity of the resin changes as the curing progresses during the friction test. This can also affect the force-displacement curve.
Y1  - 2020
U6  - https://doi.org/10.1177/1099636220923986
SN  - 1530-7972
IS  - Volume 23, Issue 7
SP  - 3017
EP  - 3043
PB  - Sage
CY  - London
ER  - 
TY  - JOUR
A1  - Czarnecki, Christian
A1  - Dietze, Christian
T1  - Gestaltungsorientierte Forschung am Beispiel der Referenzmodellierung in der Telekommunikationsindustrie
JF  - HMD Praxis der Wirtschaftsinformatik
N2  - Am Beispiel der Telekommunikationsindustrie zeigt der Beitrag eine konkrete Ausgestaltung anwendungsorientierter Forschung, die sowohl für die Praxis als auch für die Wissenschaft nutzen- und erkenntnisbringend ist. Forschungsgegenstand sind die Referenzmodelle des Industriegremiums TM Forum, die von vielen Telekommunikationsunternehmen zur Transformation ihrer Strukturen und Systeme genutzt werden. Es wird die langjährige Forschungstätigkeit bei der Weiterentwicklung und Anwendung dieser Referenzmodelle beschrieben. Dabei wird ein konsequent gestaltungsorientierter Forschungsansatz verfolgt. Das Zusammenspiel aus kontinuierlicher Weiterentwicklung in Zusammenarbeit mit einem Industriegremium und der Anwendung in vielfältigen Praxisprojekten führt zu einer erfolgreichen Symbiose aus praktischer Nutzengenerierung sowie wissenschaftlichem Erkenntnisgewinn. Der Beitrag stellt den gewählten Forschungsansatz anhand konkreter Beispiele vor. Darauf basierend werden Empfehlungen und Herausforderungen für eine gestaltungs- und praxisorientierte Forschung diskutiert.
KW  - Design Science Research
KW  - Anwendungsorientierter Forschungsansatz
KW  - Praxisprojekte
KW  - Referenzmodellierung
KW  - Enhanced Telecom Operations Map
Y1  - 2020
U6  - https://doi.org/10.1365/s40702-020-00594-y
SN  - 2198-2775
VL  - 57
IS  - 2
SP  - 310
EP  - 323
PB  - Springer Nature
CY  - Cham
ER  - 
TY  - JOUR
A1  - Bensberg, Frank
A1  - Auth, Gunnar
A1  - Czarnecki, Christian
ED  - Haake, Jörg M.
T1  - Literaturanalyse mit Text Mining
JF  - E-Learning and Education (eleed)
N2  - Die Durchführung einer systematischen Literaturrecherche ist eine zentrale Kompetenz wissenschaftlichen Arbeitens und bildet daher einen festen Ausbildungsbestandteil von Bachelor- und Masterstudiengängen. In entsprechenden Lehrveranstaltungen werden Studierende zwar mit den grundlegenden Hilfsmitteln zur Suche und Verwaltung von Literatur vertraut gemacht, allerdings werden die Potenziale textanalytischer Methoden und Anwendungssysteme (Text Mining, Text Analytics) dabei zumeist nicht abgedeckt. Folglich werden Datenkompetenzen, die zur systemgestützten Analyse und Erschließung von Literaturdaten erforderlich sind, nicht hinreichend ausgeprägt. Um diese Kompetenzlücke zu adressieren, ist an der Hochschule Osnabrück eine Lehrveranstaltung konzipiert und projektorientiert umgesetzt worden, die sich insbesondere an Studierende wirtschaftswissenschaftlicher Studiengänge richtet. Dieser Beitrag dokumentiert die fachliche sowie technische Ausgestaltung dieser Veranstaltung und zeigt Potenziale für die künftige Weiterentwicklung auf.
KW  - E-Learning
KW  - Text Mining
KW  - Text Analytics
KW  - Literaturrecherche
KW  - Literaturanalyse
Y1  - 2020
SN  - 1860-7470
N1  - Volltext, nur online
IS  - 13
SP  - 1
EP  - 13
PB  - FernUniversität in Hagen
CY  - Hagen
ER  - 
TY  - JOUR
A1  - Gerhards, Michael
A1  - Sander, Volker
A1  - Zivkovic, Miroslav
A1  - Belloum, Adam
A1  - Bubak, Marian
T1  - New approach to allocation planning of many‐task workflows on clouds
JF  - Concurrency and Computation: Practice and Experience
N2  - Experience has shown that a priori created static resource allocation plans are vulnerable to runtime deviations and hence often become uneconomic or highly exceed a predefined soft deadline. The assumption of constant task execution times during allocation planning is even more unlikely in a cloud environment where virtualized resources vary in performance. Revising the initially created resource allocation plan at runtime allows the scheduler to react on deviations between planning and execution. Such an adaptive rescheduling of a many-task application workflow is only feasible, when the planning time can be handled efficiently at runtime. In this paper, we present the static low-complexity resource allocation planning algorithm (LCP) applicable to efficiently schedule many-task scientific application workflows on cloud resources of different capabilities. The benefits of the presented algorithm are benchmarked against alternative approaches. The benchmark results show that LCP is not only able to compete against higher complexity algorithms in terms of planned costs and planned makespan but also outperforms them significantly by magnitudes of 2 to 160 in terms of required planning time. Hence, LCP is superior in terms of practical usability where low planning time is essential such as in our targeted online rescheduling scenario.
Y1  - 2020
U6  - https://doi.org/10.1002/cpe.5404
SN  - 1532-0634
VL  - 32
IS  - 2 Article e5404
SP  - 1
EP  - 16
PB  - Wiley
CY  - Chichester
ER  -