Cologne University of Applied Sciences
Koln, Germany

Cologne University of Applied science is a higher education institution in Cologne, Germany, established in 1971. It was created from a merger of numerous smaller colleges, the oldest of which was the Royal Provincial Trade School, founded in 1833, and renamed Trade College of the City of Cologne on 15 December 1879.The Cologne University of Applied science is the largest university of Applied science in Germany by number of students. Wikipedia.

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Bhandari R.,Cologne University of Applied Sciences | Stadler I.,Cologne University of Applied Sciences
Applied Energy | Year: 2011

Historically, the rural population of Nepal has been meeting their energy needs from traditional sources like fuel wood and other biomass resources. Only about 44% of the total population has access to grid electricity. Because of country's rough and mountainous topography, high cost of grid extension, and low and scattered population density, constructing some big power plants (e.g. large hydropower) can not meet the electricity needs of all people, especially those living in rural areas. Distributed generation of electricity, using environment friendly solar photovoltaic (PV) systems, might be one of the reliable alternatives for urban as well as rural electrification. This article begins with a general overview of energy resources in Nepal. Present status and perspectives of solar PV sector have also been discussed. Benefit cost and breakeven analyses of solar PV systems in Nepalese urban areas have been carried out. The breakeven year has been calculated between 2027 and 2036 for PV systems with system life time between 40 and 25 years, respectively. It has been concluded that the solar PV systems are not the economic solutions for grid connected urban areas in Nepal. On the other hand, this article concludes that the rural electrification projects should not be decided on the basis of mere monetary benefits, rather many social aspects should be considered, and in this case, there are not convincing alternatives to solar PV systems for electrification in many rural villages in Nepal. © 2009 Elsevier Ltd.

Qoaider L.,Cologne University of Applied Sciences | Steinbrecht D.,University of Rostock
Applied Energy | Year: 2010

The main objective of this work is to investigate the economic feasibility of photovoltaic technology to supply the entire energy demands to off-grid irrigated-farming-based communities in the arid regions. This aims at helping these communities to find practical solutions to cope with the rapid rising electricity generation costs, mainly by diesel generators (gensets). The genset electricity costs are typically affected by the high fossil fuel prices, the fuel transport costs and the intensive operation and maintenance (O&M) requirements. The work was conducted on a representative site from which conclusions could be drawn for similar regions. The case study was performed in the New Kalabsha Village in the Lake Nasser Region (LNR) in southern Egypt. The work involved the technical design and the calculation of the life cycle costs (LCC) of a PV system, which is able to supply the village with its entire energy demand. The PV generator was sized in such a way to daily pump 111 000 m3 of lake water to irrigate 1260 ha acreage plots and to electrify the adjacent village's households. The required pumps were designed to pump the fluctuating lake's water for a maximum differential head of 17 m in four different locations. Consequently, water from the four pumping stations flows freely by gravity forces to the different plots through overhead open canals. The electricity generation costs and the performance of the designed PV generator were compared with those of an equivalent diesel generator (genset) in order to prove its competitiveness. With this regard, the real market value of the diesel fuel of 86.55 cε l-1 was considered for calculating the costs of genset generated electricity. The results showed that the genset electricity unit costs 39 cε kW h-1 while a unit of PV electricity costs only 13 cε kW h-1 for the equivalent system size and project lifetime. Furthermore, the subsidised genset electricity cost was calculated to be 12 cε kW h-1, which is insignificantly cheaper than that of solar electricity. © 2009 Elsevier Ltd.

Kaiser A.,Cologne University of Applied Sciences
Amino Acids | Year: 2012

Translational control is a crucial component in the development and progression of different diseases. Translational control may involve selective translation of specific mRNAs, which promote cell proliferation or lead to alterations in translation factor levels and activities. Eukaryotic initiation factor 5A (eIF5A) is the only known protein to contain the unusual amino acid hypusine [N e- (4-amino-2-hydroxybutyl)-lysine], which is formed from the polyamine spermidine by two catalytic steps. eIF5A is involved in translation, elongation and stimulating peptide bond formation. Hypusination of eIF5A is essential for its activity in promoting cell proliferation. Meanwhile, there is evidence that eIF5A is a key protein in the pathogenicity of different diseases, such as diabetes, several human cancers, malaria and HIV-1 infections. Hitherto, the available data suggest that eIF5A has a role of a cell context-dependent function being more proliferative in the case of several human cancers and being involved under stress conditions in diabetes. Secondly, in HIV-1 infections and in diabetes, eIF5A also has a nuclear function by its sequence-specific binding of mRNAs as an mRNA-shuttle in conjunction with nuclear membrane export proteins. This binding may also influence the half-lives of mRNAs or their sequestration. Based on these data, there is a considerable therapeutic interest in eIF5A as a selective target for drug development through inhibition of hypusination. © Springer-Verlag 2011.

To transmit electric bulk power in an economic and efficient way over long distances up to several 1000 km it is necessary to use Ultra-High-Voltages (UHV), i.e. AC (alternating current)-voltages of 1000 kV and DC (direct current)-voltages of ±800 kV or higher. Especially the UHVDC (ultra high voltage direct current) transmission is one of the key solutions to transmit bulk power over very large distances. Two bipolar systems with transmission voltage of ±800 kV, transmission power up to 7.2 GW and length of up to 2000 km are in operation in China since 2010 and additional systems especially in China and India are planned. So it seems that the UHVDC technology is state of the art and can be used easily. But there are some restrictions which make it difficult to use UHVDC transmission in all cases. To analyze this in detail, the state of the art of long distance UHVDC transmission systems is summarized and the possible future development is analyzed. Different aspects are discussed, which will possibly limit the use of the UHVDC technology in future. © 2012 Elsevier Ltd.

Leitner S.,Cologne University of Applied Sciences
Journal of European Social Policy | Year: 2010

The article compares the development of childcare policies in Germany and Austria. Although both countries are characterized by a conservative welfare regime, they developed very different childcare policies. Historically speaking, Austria pioneered in the introductory period whereas Germany outpaced Austria with the latest reforms. The article argues that ideological party differences account for policy change. The gender and family models promoted by the governing parties shaped the development of childcare policies decisively. But party positions changed over time due to general emancipation processes, intra-party conflicts and constraints by coalition partners. Thus, the 'parties matter' thesis explains policy development only partly. The historical context of policy making has to be taken into consideration as well. © 2010 The Author(s).

May H.-O.,FH Darmstadt | Mausbach P.,Cologne University of Applied Sciences
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

The behavior of thermodynamic response functions and the thermodynamic scalar curvature in the supercritical region have been studied for a Lennard-Jones fluid based on a revised modified Benedict-Webb-Rubin equation of state. Response function extrema are sometimes used to estimate the Widom line, which is characterized by the maxima of the correlation lengths. We calculated the Widom line for the Lennard-Jones fluid without using any response function extrema. Since the volume of the correlation length is proportional to the Riemannian thermodynamic scalar curvature, the locus of the Widom line follows the slope of maximum curvature. We show that the slope of the Widom line follows the slope of the isobaric heat capacity maximum only in the close vicinity of the critical point and that, therefore, the use of response function extrema in this context is problematic. Furthermore, we constructed the vapor-liquid coexistence line for the Lennard-Jones fluid using the fact that the correlation length, and therefore the thermodynamic scalar curvature, must be equal in the two coexisting phases. We compared the resulting phase envelope with those from simulation data where multiple histogram reweighting was used and found striking agreement between the two methods. © 2012 American Physical Society.

Cologne University of Applied Sciences | Date: 2012-11-08

The invention relates to a test body for checking the transmission properties of volume tomographs, in particular radiological tomographs, which comprises several plates (2) that are connected to form a stack, in which adjacent plates (2) contact each other and said body comprises spheres (4) made of at least one material that is different from the plates (2) and having different diameters, wherein the respective spheres (4) are arranged in and/or between at least some of the plates (2), and wherein on/in the test body, preferably in the stack, at least one rod-shaped hollow profile, in particular at least one pipe having a circular cross section, is arranged. The invention further relates to a method for checking the transmission properties of a tomograph using such a test body (1).

Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2011.4.1 | Award Amount: 2.30M | Year: 2012

The aim of the TaaS project is to create a cloud-based platform for acquiring, cleaning up, sharing, and reusing multilingual terminological data, one of the most important language resources for industry, academia, and society in general. The motivation of the TaaS project is to address an evident need for instant access to the most recent terms and direct user involvement in the creation and sharing of terminology data. Such a platform will provide a variety of online services for key terminology tasks becoming an integral part of the multifaceted global cloud-based service infrastructure. TaaS services will perform term identification in the user provided documents. The platform will perform terminology extraction and return a list of term candidates. The TaaS infrastructure will ensure an automatic acquisition of translation equivalents for the obtained term candidates in the required target languages. Besides querying major terminology databases, term candidates will be extracted from the huge array of multilingual texts on the web. Users will clean up the obtained data and store it in the shared terminology repository. TaaS will cover all EU official languages and address the terminology needs for both human and machine users. Open access to data, API access to services, reliance on terminology data exchange standards opens a variety of application possibilities. The TaaS project will develop an innovative cloud-based data collection model combining both the latest techniques for automated data extraction and user involvement in data clean-up and sharing. Public terminology resources will be shared via well-established channels for sharing of language resources. Thus, the more users the platform will have the larger volumes of multilingual terminological data will be acquired, cleaned and then shared and reused via different channels. TaaS platform will serve terminology needs of a wide range of applications from which three usage scenarios will be elaborated.

Reidenbach H.-D.,Cologne University of Applied Sciences
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

Although it is well-known that dazzle, flash-blindness and afterimages may be caused by bright optical radiation, only sparse quantitative data are available with regard to the effects arising from low power laser products. Indirect effects like temporary blinding might result in serious incidents or even accidents due to the alteration of visual functions like visual acuity, contrast sensitivity and color discrimination. In order to determine the degree and duration of impairment resulting from dazzle, flash-blindness and afterimages, caused by a laser beam, an investigation has been performed with the goal to improve the current knowledge as far as especially the visual acuity recovery duration is concerned. Two different test set-ups were designed and applied in order to determine the afterimage duration and the recovery time for visual acuity after temporary blinding from a laser, respectively. In order to get the desired information a helium-neon laser was mounted on a movable assembly where the respective beam position and direction could be set up on a semicircle. In addition the mount could be inclined in a vertical plane in order to increase the variability of feasible settings. The power was adjusted in several steps in order to investigate the respective dependence of the afterimage. The investigations were relatively time consuming, since re-adaptation of about half an hour was necessary after every exposure in order not to falsify the results. The trials have been done with several volunteers in the laboratory. After the experimental mapping of the local afterimage duration for the various sites on the retina the foveal afterimage duration t af,fv produced by a red laser beam was determined. The investigations have shown a strong dependence on the angle between the line of sight and the beam direction. Besides a maximum of 300 s the dose relationship t af,fv/s = 50.6·ln[(P·texp)/μJ] - 13.4 for laser output powers P between 10 μW and 30 μW with exposure durations texp from 0.25 s up to 10 s was found. The inability to read due to the disturbance produced by afterimages lasts for about 20 s even if the exposure is not more than 0.25 s from a laser with about 0.8 mW optical output power. In addition to the physiological effects of temporary blinding the psychological glare was determined as a function of the angle between line of sight and beam direction. It was found that already at output powers below 30 μW of a He-Ne-laser the subjects reported intense glare effects and felt uncomfortable due to the high brightness. Instead of the standard visual acuity measurement used by eye care professionals, a reading test on a computer monitor was applied after laser irradiation. In this case two different lasers were used as a dazzling light source, one with a wavelength of 632.8 nm and the other with 532 nm. The maximum applied optical power in a 7-mm aperture, which is equivalent to the pupil diameter of a dark adapted eye, was 0.783 mW. The exposure durations were chosen as 0.25 s, 0.5 s, 1 s, 5 s, and 20 s. © 2010 SPIE.

Agency: European Commission | Branch: FP7 | Program: CP | Phase: FoF-ICT-2011.7.1 | Award Amount: 11.74M | Year: 2012

The production and ramp-up of complex and highly customized products are exceptionally challenging for planning and control, especially in small lot sizes. Daily challenges like late requests for change, immature high technology products and processes create significant risks. The occurring risks are bigger than production of big series such as automotive. Thus, new ICT-based approaches are required. The aim is to develop mitigation strategies to respond faster to unexpected events. Therefore the knowledge base has to be enriched for real-time decision support, to detect early warning and to accelerate learning. Our approach is based on a new generation of service orientated enterprise information platforms, a service orientated bus integrating service-based architecture and knowledge-based multi-agent systems (MAS). A holonic MAS combined with a service architecture will improve performance and scalability beyond the state of the art. The solution integrates multiple layers of sensors, legacy systems and agent-based tools for beneficial services like learning, quality, risk and cost management. Additionally the ecological footprints will be reduced. The ARUM solution will run in two modes: predictive and real time simulation. The predictive mode supports the planning phase whereas the real-time operations mode supports dynamic, time-, cost- and risk-oriented re-planning of operations. The provision of information for engineering to alter in case of immaturity or late requests for changes is supported equally. ARUM is strongly end-user driven and the results will be tested on three industrial use cases with a focus on aircraft, aircraft interiors and ship manufacturing. The solution will be validated in a real industrial environment by industrial partners and benchmarked against todays ICT solutions. In collaboration with universities a test-bed will be established for design and testing of ARUM systems and tools and will be opened for dissemination and demonstration.

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