@misc{Mehlhorn2017, author = {Mehlhorn, Nils}, title = {Modern Cross-Platform Development for Mobile Applications}, address = {D{\"u}sseldorf}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-11276}, pages = {43}, year = {2017}, abstract = {While developing for multiple platforms at once seems like a convenient solution, there are several challenges arising when trying to abstract the entire mobile development. This paper is meant to evaluate current cross-platform development for mobile applications. The background for its necessity, its conceptual approach and the problems to face when developing cross-platform were determined and explained in detail. Afterwards, certain solutions were evaluated against the former insights. Based on the results, an informed discussion and conclusion was performed. The mobile environment consist of only two big players by now, Android and iOS. These operating systems differ in architecture, design and consequently in the way applications are developed for each of them. Therefore, high demands are made towards cross-platform solutions. Tools which allow for the creation of applications for multiple platforms at once have to match native applications in regard to user experience and performance. At the same time they need to be able to optimize developments with the goal of being cost efficient. Apache Cordova, Xamarin and NativeScript were selected for evaluation in regard to their ability to meet these requirements. Cordova acts as the comparison group of cross-platform tools. It is the big player in the field and there are reasons for this. However, aspiring solutions with higher nativity and ambitious approaches are emerging. Xamarin and NativeScript deliver top quality results while offering loosely coupled developments. Therefore it is possible to develop high quality applications and still benefit from the advantages of platform-independent solutions. As a consequence mobile development is about to change in the foreseeable future. More sophisticated approaches may lead to a higher number of developments done cross-platform, and rightfully so.}, language = {en} } @masterthesis{Mehlhorn2017, type = {Bachelor Thesis}, author = {Mehlhorn, Nils}, title = {Mobile Cross-Platform Development from a Progressive Perspective}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-11285}, school = {Hochschule D{\"u}sseldorf}, year = {2017}, abstract = {Progressive web applications (PWAs) seem to be the next big thing in the mobile landscape. These are web applications with "super-powers" which are meant to provide the kinds of user experiences previously only native mobile applications could. Therefore they are able to match native applications in their capabilities but still thrive on the reachability of the web. They achieve this by implementing certain characteristics which originate from innovative standards and sophisticated best practices. Conveniently, as it is the web, PWAs are working seamlessly cross-platform. One of the closest things to a PWA so far may be an application created with the NativeScript framework. Such an application is also developed with web technologies yet able to use any native interface directly. This is made possible by using a designated runtime for mediating between JavaScript and the mobile system. Eventually, NativeScript is able to offer a high degree nativity yet also of convenient abstraction during development. This paper is set out to deliver further insight into both approaches by contrasting them based on the characteristics of PWAs. For this purpose, these characteristics are elaborated and adjusted to be applicable to native mobile applications. Hence a reasonable basis for what to expect from a native application is derived. Then NativeScript is assessed on this basis by the means of transferable concepts and technologies as well as a prototypic mobile application. Finally, an informed discussion and conclusion is performed based on the results. The comprehensive characteristics of PWAs resolve previous shortcomings with well thought out concepts and new technologies. These are transferable to native mobile applications to a far extent and may also be put into practice with NativeScript. The framework's approach may be very well called ingenious, however, in the long run it might fall short of the innovative concept of PWAs. Having said this, it is still able to serve as a practical measure for creating appealing user experiences for multiple systems with arguably little effort. Due to large overlap a transformation between the two application types is a realistic option. Either way, web technologies are far from what they used to be and it is exciting to see how the mobile and web landscape will evolve in the future.}, language = {en} } @techreport{Marke2019, author = {Marke, Ute}, title = {Land of High Hopes}, publisher = {Hochschule D{\"u}sseldorf}, address = {D{\"u}sseldorf}, organization = {Hochschule D{\"u}sseldorf}, doi = {10.20385/k4fh-bd11}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-17683}, pages = {18}, year = {2019}, abstract = {We are living in the era of sophisticated, state-of-the-art technology, artificial intelligence, accelerating data sciences at ultimate speed and sheer unlimited possibilities. We are able to shoot unmanned rockets equipped with vehicles into the orbit. We can afford to spend fortunes on research and development. However, and that leaves me bloodcurdling and furious, we haven´t managed yet to settle at least some of the most pressing global humanitarian needs: access to food, water, electricity, education and healthcare. So how can we be proud of any achievements? What does make us proud anyway?! ...}, language = {en} } @article{MarcinkowskideHaasKohler2025, author = {Marcinkowski, Frank and de Haas, Hella and Kohler, Sarah}, title = {Flight or fight? - How the coronavirus pandemic has affected scientists' willingness to engage with the public}, series = {Humanities and Social Sciences Communications}, volume = {12}, journal = {Humanities and Social Sciences Communications}, publisher = {Springer Nature}, issn = {2662-9992}, doi = {10.1057/s41599-025-05023-3}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-60444}, pages = {11}, year = {2025}, abstract = {During the coronavirus pandemic, scientists who worked to overcome the outbreak received recognition, but also opposition and even hostility. This article examines how the experience of the pandemic has affected the willingness of scientists to engage with the public. Derived from a comprehensive survey of 4207 scientists at German universities and research institutions, animosity towards scientists during the pandemic has created a sense of insecurity that may cause them to withdraw from the public eye. Depending on the relative strength of two cognitive appraisals, the severity of the threat and the appropriateness of the retreat option, the likelihood of respondents engaging with the public varies significantly.}, subject = {COVID-19-Pandemie}, language = {en} } @article{MandalMannaBiswasetal.2026, author = {Mandal, Dipak Kumar and Manna, Nirmal K. and Biswas, Nirmalendu and Rudra, Tansu and Kumar, Rajesh and Benim, Ali Cemal}, title = {Enhanced heat transport in magneto-nanofluidic thermal systems: adiabatic block effects in grooved channels and ANN modeling}, series = {International Journal of Thermofluids}, volume = {31}, journal = {International Journal of Thermofluids}, publisher = {Elsevier}, issn = {2666-2027}, doi = {10.1016/j.ijft.2025.101515}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-60127}, year = {2026}, abstract = {This study investigates heat transfer enhancement in magneto-nanofluidic systems through the strategic placement of adiabatic blocks in grooved channels. Using CuO-H2O nanofluid in a bottom-heated channel with circular expansion, we examine the complex interactions between forced convection, magnetic fields, and uoyancy effects. Through systematic numerical analysis, we explore the combined influences of Rayleigh, Reynolds, and Hartmann numbers on thermal performance. Our findings reveal significant heat transfer enhancement (up to 137 \%) under optimal conditions, particularly with vertical magnetic field orientation at Re = 100 and Ha = 30. The results demonstrate how adiabatic blocks modify flow structures, with larger blocks diminishing vortex intensity while elevated Ra generates secondary vortices that interact with primary circulations. Magnetic field effects show notable dependence on orientation, with vertical fields generally promoting better heat transfer than horizontal configurations. To complement the numerical analysis, we develop a predictive model using Artificial Neural Network (ANN) for Nusselt numbers across various operating conditions, achieving over 99 \% accuracy. The integrated computational-ANN approach offers significant advancements in optimizing thermal systems in various areas, ranging from electronics cooling to microfluidic devices.}, language = {en} } @article{MandalGuptaBiswasetal.2025, author = {Mandal, Dipak Kumar and Gupta, Kritesh Kumar and Biswas, Nirmalendu and Manna, Nirmal K. and Santra, Somnath and Benim, Ali Cemal}, title = {Optimization of hybrid solar chimney power plants (HSCPPs): A review of multi-objective approaches}, series = {Applied Energy}, volume = {396}, journal = {Applied Energy}, publisher = {Elsevier}, issn = {0306-2619}, doi = {10.1016/j.apenergy.2025.126214}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-54199}, pages = {25}, year = {2025}, subject = {Erneuerbare Energien}, language = {en} } @article{MandalBoseBiswasetal.2024, author = {Mandal, Dipak Kumar and Bose, Sharmistha and Biswas, Nirmalendu and Manna, Nirmal K. and Cuce, Erdem and Benim, Ali Cemal}, title = {Solar Chimney Power Plants for Sustainable Air Quality Management Integrating Photocatalysis and Particulate Filtration: A Comprehensive Review}, series = {Sustainability}, volume = {16}, journal = {Sustainability}, number = {6}, publisher = {MDPI}, issn = {2071-1050}, doi = {10.3390/su16062334}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-45814}, pages = {31}, year = {2024}, abstract = {Urban air pollution has become a pressing challenge in recent times, demanding innovative solutions. This review delves into the potential of Solar Chimney Power Plants (SCPPs) as a sustainable approach to mitigating air pollution. The idea of mitigation of pollution may be an added advantage to the use of SCPPs in practice. Recent advancements, such as the integration of photocatalytic reactors (PCRs) for the elimination of greenhouse gases (GHGs), emphasizing the importance of addressing non-CO2 GHGs like CH4 and N2O are analyzed. The novelty of this review is that it not only focuses on the shifting and removal of particulate matter but also on the removal of greenhouse gases. Numerous case studies, ranging from filter-equipped SCPPs to Solar-Assisted Large-Scale Cleaning Systems (SALSCSs), are reviewed, providing a comprehensive understanding of their design, performance, and potential benefits. This review serves as a guide for researchers and policymakers, emphasizing the need for multifaceted approaches to address the intricate nexus of air pollution, renewable energy generation, and climate change mitigation.}, subject = {Luftverschmutzung}, language = {en} } @article{MandalBiswasMannaetal.2024, author = {Mandal, Dipak Kumar and Biswas, Nirmalendu and Manna, Nirmal K. and Gayen, Dilip Kumar and Benim, Ali Cemal}, title = {An application of artificial neural network (ANN) for comparative performance assessment of solar chimney (SC) plant for green energy production}, series = {Scientific Reports}, volume = {14}, journal = {Scientific Reports}, number = {1}, publisher = {Springer Nature}, issn = {2045-2322}, doi = {10.1038/s41598-023-46505-1}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-45190}, year = {2024}, abstract = {This study aims to optimize the power generation of a conventional Manzanares solar chimney (SC) plant through strategic modifications to the collector inlet height, chimney diameter, and chimney divergence. Employing a finite volume-based solver for numerical analysis, we systematically scrutinize influential geometric parameters, including collector height (hi = 1.85 to 0.1 m), chimney inlet diameter (dch = 10.16 to 55.88 m), and chimney outlet diameter (do = 10.16 to 30.48 m). Our findings demonstrate that reducing the collector inlet height consistently leads to increased power output. The optimal collector inlet height of hi = 0.2 m results in a significant power increase from 51 to 117.42 kW (~ 2.3 times) without additional installation costs, accompanied by an efficiency of 0.25\%. Conversely, enlarging the chimney diameter decreases the chimney base velocity and suction pressure. However, as turbine-driven power generation rises, the flow becomes stagnant beyond a chimney diameter of 45.72 m. At this point, power generation reaches 209 kW, nearly four times greater than the Manzanares plant, with an efficiency of 0.44\%. Nevertheless, the cost of expanding the chimney diameter is substantial. Furthermore, the impact of chimney divergence is evident, with power generation, collector efficiency, overall efficiency, and collector inlet velocity all peaking at an outer chimney diameter of 15.24 m (corresponding to an area ratio of 2.25). At this configuration, power generation increases to 75.91 kW, approximately 1.5 times more than the initial design. Remarkably, at a low collector inlet height of 0.2 m, combining it with a chimney diameter of 4.5 times the chimney inlet diameter (4.5dch) results in an impressive power output of 635.02 kW, signifying a substantial 12.45-fold increase. To model the performance under these diverse conditions, an artificial neural network (ANN) is effectively utilized.}, language = {en} } @article{MandalBiswasMannaetal.2024, author = {Mandal, Dipak Kumar and Biswas, Nirmalendu and Manna, Nirmal K and Benim, Ali Cemal}, title = {Impact of chimney divergence and sloped absorber on energy efficacy of a solar chimney power plant (SCPP)}, series = {Ain Shams Engineering Journal}, journal = {Ain Shams Engineering Journal}, publisher = {Elsevier}, issn = {2090-4495}, doi = {10.1016/j.asej.2023.102390}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:due62-opus-42410}, year = {2024}, abstract = {A numerical study is carried out meticulously to scrutinize the impact of different shapes of chimneys like circular (outer dia, dc), convergent (outer dia, 0.5dc), divergent (outer dia, 1.5dc), sudden contraction (outer dia, 0.5dc), and sudden expansion (outer dia, 1.5dc) on the performance of an SCPP. Furthermore, the parametric impact with different chimney divergence angles (CDA, ϕ), and ground absorber slope angle (GSA, γ) on the SCPP performance is also scrutinized. Optimum divergence angle (ϕ=+0.75◦) enhances the power generation up to ~ 47\% (76 kW) with a horizontal ground absorber surface. An increase or decrease in CDA lessens the power generation. With a sloped ground absorber angle γ=0.6◦, the gain in power generation is 60\% (82 kW). The study of combination of ground sloped absorber (γ=0.6◦) and divergent chimney (ϕ=+0.75◦) shows enhancement of the power generation upto 80\% (92 kW) more than the classical Manzaranes plant.}, language = {en} } @article{MaginStarkJanduraetal.2023, author = {Magin, Melanie and Stark, Birgit and Jandura, Olaf and Udris, Linards and Riedl, Andreas and Klein, Miriam and Eisenegger, Mark and K{\"o}sters, Raphael and Hofstetter Furrer, Brigitte}, title = {Seeing the Whole Picture. Towards a Multi-perspective Approach to News Content Diversity based on Liberal and Deliberative Models of Democracy}, series = {Journalism Studies}, volume = {24}, journal = {Journalism Studies}, number = {5}, publisher = {Taylor \& Francis}, issn = {1461-670X}, doi = {10.1080/1461670X.2023.2178248}, pages = {669 -- 696}, year = {2023}, abstract = {By providing diverse news content, news media are key for a well- functioning public sphere. However, agreement on how to measure news content diversity is lacking. Research often refers to democratic theory as normative reference point, but different models of democracy understand news content diversity differently. Our study makes a unique, innovative contribution to this field: (1) We develop a methodological framework for measuring news content diversity, that is a set of comprehensive measuring instruments that derive different operationalizations of topic and actor diversity each from liberal and deliberative democratic theories. (2) Considering that a good public discourse requires more than diversity, we analyze news content diversity in the context of four other journalistic standards: neutrality, rationality, discursivity, and civility. (3) We prove the applicability of our measuring instruments by means of a standardized content analysis of six German news media as a case study. The different quality profiles of these outlets our analysis reveals are explained by their different functions in the media system. Our study shows how important a multi-perspectival normative approach to news content diversity is, both empirically and theoretically. Future studies on news content diversity should make their normative foundations transparent and derive their indicators purposefully therefrom.}, subject = {Demokratie}, language = {en} }