@book{Laack2022, author = {Laack, Walter van}, title = {Aufruf zum Nachdenken: Corona und neue Kriege - Wie kann die Menschheit {\"u}berleben?}, publisher = {van Laack GmbH}, address = {Aachen}, isbn = {978-3-936624-56-4}, pages = {56 Seiten}, year = {2022}, language = {de} } @book{Laack2022, author = {Laack, Walter van}, title = {Schnittstelle Tod: Was lernen wir durch Corona {\"u}ber Leben und Tod?}, publisher = {van Laack GmbH}, address = {Aachen}, isbn = {978-3-936624-53-3}, pages = {108 Seiten}, year = {2022}, language = {de} } @book{Laack2022, author = {Laack, Walter van}, title = {Greater Than the Entire Universe}, publisher = {van Laack GmbH}, address = {Aachen}, isbn = {978-3-936624-52-6}, pages = {120 Seiten}, year = {2022}, language = {en} } @inproceedings{WeldenSeverinsPoghossianetal.2022, author = {Welden, Melanie and Severins, Robin and Poghossian, Arshak and Wege, Christina and Siegert, Petra and Keusgen, Michael and Sch{\"o}ning, Michael Josef}, title = {Studying the immobilization of acetoin reductase with Tobacco mosaic virus particles on capacitive field-effect sensors}, series = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)}, booktitle = {2022 IEEE International Symposium on Olfaction and Electronic Nose (ISOEN)}, publisher = {IEEE}, isbn = {978-1-6654-5860-3 (Online)}, doi = {10.1109/ISOEN54820.2022.9789657}, pages = {4 Seiten}, year = {2022}, abstract = {A capacitive electrolyte-insulator-semiconductor (EISCAP) biosensor modified with Tobacco mosaic virus (TMV) particles for the detection of acetoin is presented. The enzyme acetoin reductase (AR) was immobilized on the surface of the EISCAP using TMV particles as nanoscaffolds. The study focused on the optimization of the TMV-assisted AR immobilization on the Ta 2 O 5 -gate EISCAP surface. The TMV-assisted acetoin EISCAPs were electrochemically characterized by means of leakage-current, capacitance-voltage, and constant-capacitance measurements. The TMV-modified transducer surface was studied via scanning electron microscopy.}, language = {en} } @article{BialonskiGrieger2023, author = {Bialonski, Stephan and Grieger, Niklas}, title = {Der KI-Chatbot ChatGPT: Eine Herausforderung f{\"u}r die Hochschulen}, series = {Die neue Hochschule}, volume = {2023}, journal = {Die neue Hochschule}, number = {1}, publisher = {HLB}, address = {Bonn}, issn = {0340-448X}, doi = {10.5281/zenodo.7533758}, pages = {24 -- 27}, year = {2023}, abstract = {Essays, Gedichte, Programmcode: ChatGPT generiert automatisch Texte auf bisher unerreicht hohem Niveau. Dieses und nachfolgende Systeme werden nicht nur die akademische Welt nachhaltig ver{\"a}ndern.}, language = {de} } @misc{TopcuMadabhushiStaat2022, author = {Topcu, Murat and Madabhushi, Gopal Santana Phani and Staat, Manfred}, title = {Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster}, doi = {10.6084/m9.figshare.19333295.v2}, year = {2022}, abstract = {Datasets from FEM Simulations done with COMSOL Multiphysics and Code_Aster for an elastic stress transfer between matrix and fibres having a variable radius.}, language = {en} } @article{AngermannGuenthnerHanssenetal.2022, author = {Angermann, Susanne and G{\"u}nthner, Roman and Hanssen, Henner and Lorenz, Georg and Braunisch, Matthias C. and Steubl, Dominik and Matschkal, Julia and Kemmner, Stephan and Hausinger, Renate and Block, Zenonas and Haller, Bernhard and Heemann, Uwe and Kotliar, Konstantin and Grimmer, Timo and Schmaderer, Christoph}, title = {Cognitive impairment and microvascular function in end-stage renal disease}, series = {International Journal of Methods in Psychiatric Research (MPR)}, volume = {31}, journal = {International Journal of Methods in Psychiatric Research (MPR)}, number = {2}, publisher = {Wiley}, issn = {1049-8931 (Print)}, doi = {10.1002/mpr.1909}, pages = {1 -- 10}, year = {2022}, abstract = {Objective Hemodialysis patients show an approximately threefold higher prevalence of cognitive impairment compared to the age-matched general population. Impaired microcirculatory function is one of the assumed causes. Dynamic retinal vessel analysis is a quantitative method for measuring neurovascular coupling and microvascular endothelial function. We hypothesize that cognitive impairment is associated with altered microcirculation of retinal vessels. Methods 152 chronic hemodialysis patients underwent cognitive testing using the Montreal Cognitive Assessment. Retinal microcirculation was assessed by Dynamic Retinal Vessel Analysis, which carries out an examination recording retinal vessels' reaction to a flicker light stimulus under standardized conditions. Results In unadjusted as well as in adjusted linear regression analyses a significant association between the visuospatial executive function domain score of the Montreal Cognitive Assessment and the maximum arteriolar dilation as response of retinal arterioles to the flicker light stimulation was obtained. Conclusion This is the first study determining retinal microvascular function as surrogate for cerebral microvascular function and cognition in hemodialysis patients. The relationship between impairment in executive function and reduced arteriolar reaction to flicker light stimulation supports the involvement of cerebral small vessel disease as contributing factor for the development of cognitive impairment in this patient population and might be a target for noninvasive disease monitoring and therapeutic intervention.}, language = {en} } @article{AkimbekovDigelTastambeketal.2022, author = {Akimbekov, Nuraly S. and Digel, Ilya and Tastambek, Kuanysh T. and Marat, Adel K. and Turaliyeva, Moldir A. and Kaiyrmanova, Gulzhan K.}, title = {Biotechnology of Microorganisms from Coal Environments: From Environmental Remediation to Energy Production}, series = {Biology}, volume = {11}, journal = {Biology}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2079-7737}, doi = {10.3390/biology11091306}, pages = {47 Seiten}, year = {2022}, abstract = {It was generally believed that coal sources are not favorable as live-in habitats for microorganisms due to their recalcitrant chemical nature and negligible decomposition. However, accumulating evidence has revealed the presence of diverse microbial groups in coal environments and their significant metabolic role in coal biogeochemical dynamics and ecosystem functioning. The high oxygen content, organic fractions, and lignin-like structures of lower-rank coals may provide effective means for microbial attack, still representing a greatly unexplored frontier in microbiology. Coal degradation/conversion technology by native bacterial and fungal species has great potential in agricultural development, chemical industry production, and environmental rehabilitation. Furthermore, native microalgal species can offer a sustainable energy source and an excellent bioremediation strategy applicable to coal spill/seam waters. Additionally, the measures of the fate of the microbial community would serve as an indicator of restoration progress on post-coal-mining sites. This review puts forward a comprehensive vision of coal biodegradation and bioprocessing by microorganisms native to coal environments for determining their biotechnological potential and possible applications.}, language = {en} } @article{RuebbelkeVoegeleGrajewskietal.2023, author = {R{\"u}bbelke, Dirk and V{\"o}gele, Stefan and Grajewski, Matthias and Zobel, Luzy}, title = {Cross border adjustment mechanism: Initial data for the assessment of hydrogen-based steel production}, series = {Data in Brief}, volume = {47}, journal = {Data in Brief}, number = {Article 108907}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2352-3409}, doi = {10.1016/j.dib.2023.108907}, pages = {1 -- 5}, year = {2023}, abstract = {Ambitious climate targets affect the competitiveness of industries in the international market. To prevent such industries from moving to other countries in the wake of increased climate protection efforts, cost adjustments may become necessary. Their design requires knowledge of country-specific production costs. Here, we present country-specific cost figures for different production routes of steel, paying particular attention to transportation costs. The data can be used in floor price models aiming to assess the competitiveness of different steel production routes in different countries (R{\"u}bbelke, 2022).}, language = {en} } @phdthesis{Gaigall2016, author = {Gaigall, Daniel}, title = {Vergleich von statistischen Tests im verbundenen und unabh{\"a}ngigen Stichprobenfall}, publisher = {Gottfried Wilhelm Leibniz Universit{\"a}t Hannover}, address = {Hannover}, doi = {10.15488/8678}, pages = {281 Seiten}, year = {2016}, abstract = {Es werden Effizienzbegriffe zum Vergleich von statistischen Tests basierend auf verschiedenen statistischen Experimenten eingef{\"u}hrt. Dabei handelt es sich um die schon aus dem Vergleich von statistischen Tests in je demselben Modell bekannten asymptotischen relativen Effizienzen wie die Hodges-Lehmann-Effizienz, die Bahadur-Effizienz und die Pitman-Effizienz sowie um Kriterien basierend auf Volumina von Konfidenzbereichen. Effizienzaussagen werden unter anderem f{\"u}r Likelihood-Quotienten-Tests und Waldsche Tests im Rahmen eines allgemeinen multivariaten parametrischen Modells erhalten. Statistische Tests zur Pr{\"u}fung von Hypothesen {\"u}ber die relative Wirksamkeit zweier Experimente werden vorgeschlagen. Auf der Grundlage der erhaltenen Ergebnisse erfolgt ein Vergleich der Wirksamkeit von korrespondierenden Verfahren bei verbundener Stichprobenerhebung und unabh{\"a}ngiger Stichprobenerhebung. Die Rolle der Kovarianzmatrix bei verbundener Stichprobenerhebung wird insbesondere unter der Annahme, dass die zugrunde liegenden Verteilungen durch k-parametrische Exponentialfamilien modellierbar sind, herausgearbeitet. Verbindungen zu Effizienzbegriffen bei Punkt- und Konfidenzbereichssch{\"a}tzverfahren werden aufgezeigt. Ausf{\"u}hrlichere Untersuchungen betreffen die korrespondierenden Hotellingschen T²-Tests im multivariaten Normalverteilungsfall, die klassischen Homogenitatstests bei k × k-Kontingenztafeln und die Wilcoxon Tests in nichtparametrischen Lagealternativmodellen}, language = {de} } @article{BaringhausGaigall2017, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On Hotelling's T² test in a special paired sample case}, series = {Communications in Statistics - Theory and Methods}, volume = {48}, journal = {Communications in Statistics - Theory and Methods}, number = {2}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-415X}, doi = {10.1080/03610926.2017.1408828}, pages = {257 -- 267}, year = {2017}, abstract = {In a special paired sample case, Hotelling's T² test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.}, language = {en} } @article{BaringhausGaigall2017, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {Hotelling's T² tests in paired and independent survey samples: An efficiency comparison}, series = {Journal of Multivariate Analysis}, volume = {2017}, journal = {Journal of Multivariate Analysis}, number = {154}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2016.11.004}, pages = {177 -- 198}, year = {2017}, abstract = {Hotelling's T² tests in paired and independent survey samples are compared using the traditional asymptotic efficiency concepts of Hodges-Lehmann, Bahadur and Pitman, as well as through criteria based on the volumes of corresponding confidence regions. Conditions characterizing the superiority of a procedure are given in terms of population canonical correlation type coefficients. Statistical tests for checking these conditions are developed. Test statistics based on the eigenvalues of a symmetrized sample cross-covariance matrix are suggested, as well as test statistics based on sample canonical correlation type coefficients.}, language = {en} } @article{BaringhausGaigall2019, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On an asymptotic relative efficiency concept based on expected volumes of confidence regions}, series = {Statistics - A Journal of Theoretical and Applied Statistic}, volume = {53}, journal = {Statistics - A Journal of Theoretical and Applied Statistic}, number = {6}, publisher = {Taylor \& Francis}, address = {London}, issn = {1029-4910}, doi = {10.1080/02331888.2019.1683560}, pages = {1396 -- 1436}, year = {2019}, abstract = {The paper deals with an asymptotic relative efficiency concept for confidence regions of multidimensional parameters that is based on the expected volumes of the confidence regions. Under standard conditions the asymptotic relative efficiencies of confidence regions are seen to be certain powers of the ratio of the limits of the expected volumes. These limits are explicitly derived for confidence regions associated with certain plugin estimators, likelihood ratio tests and Wald tests. Under regularity conditions, the asymptotic relative efficiency of each of these procedures with respect to each one of its competitors is equal to 1. The results are applied to multivariate normal distributions and multinomial distributions in a fairly general setting.}, language = {en} } @article{Gaigall2019, author = {Gaigall, Daniel}, title = {On a new approach to the multi-sample goodness-of-fit problem}, series = {Communications in Statistics - Simulation and Computation}, volume = {53}, journal = {Communications in Statistics - Simulation and Computation}, number = {10}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-4141}, doi = {10.1080/03610918.2019.1618472}, pages = {2971 -- 2989}, year = {2019}, abstract = {Suppose we have k samples X₁,₁,…,X₁,ₙ₁,…,Xₖ,₁,…,Xₖ,ₙₖ with different sample sizes ₙ₁,…,ₙₖ and unknown underlying distribution functions F₁,…,Fₖ as observations plus k families of distribution functions {G₁(⋅,ϑ);ϑ∈Θ},…,{Gₖ(⋅,ϑ);ϑ∈Θ}, each indexed by elements ϑ from the same parameter set Θ, we consider the new goodness-of-fit problem whether or not (F₁,…,Fₖ) belongs to the parametric family {(G₁(⋅,ϑ),…,Gₖ(⋅,ϑ));ϑ∈Θ}. New test statistics are presented and a parametric bootstrap procedure for the approximation of the unknown null distributions is discussed. Under regularity assumptions, it is proved that the approximation works asymptotically, and the limiting distributions of the test statistics in the null hypothesis case are determined. Simulation studies investigate the quality of the new approach for small and moderate sample sizes. Applications to real-data sets illustrate how the idea can be used for verifying model assumptions.}, language = {en} } @article{DitzhausGaigall2018, author = {Ditzhaus, Marc and Gaigall, Daniel}, title = {A consistent goodness-of-fit test for huge dimensional and functional data}, series = {Journal of Nonparametric Statistics}, volume = {30}, journal = {Journal of Nonparametric Statistics}, number = {4}, publisher = {Taylor \& Francis}, address = {Abingdon}, issn = {1029-0311}, doi = {10.1080/10485252.2018.1486402}, pages = {834 -- 859}, year = {2018}, abstract = {A nonparametric goodness-of-fit test for random variables with values in a separable Hilbert space is investigated. To verify the null hypothesis that the data come from a specific distribution, an integral type test based on a Cram{\´e}r-von-Mises statistic is suggested. The convergence in distribution of the test statistic under the null hypothesis is proved and the test's consistency is concluded. Moreover, properties under local alternatives are discussed. Applications are given for data of huge but finite dimension and for functional data in infinite dimensional spaces. A general approach enables the treatment of incomplete data. In simulation studies the test competes with alternative proposals.}, language = {en} } @article{BaringhausGaigallThiele2018, author = {Baringhaus, Ludwig and Gaigall, Daniel and Thiele, Jan Philipp}, title = {Statistical inference for L²-distances to uniformity}, series = {Computational Statistics}, volume = {2018}, journal = {Computational Statistics}, number = {33}, publisher = {Springer}, address = {Berlin}, issn = {1613-9658}, doi = {10.1007/s00180-018-0820-0}, pages = {1863 -- 1896}, year = {2018}, abstract = {The paper deals with the asymptotic behaviour of estimators, statistical tests and confidence intervals for L²-distances to uniformity based on the empirical distribution function, the integrated empirical distribution function and the integrated empirical survival function. Approximations of power functions, confidence intervals for the L²-distances and statistical neighbourhood-of-uniformity validation tests are obtained as main applications. The finite sample behaviour of the procedures is illustrated by a simulation study.}, language = {en} } @article{BaringhausGaigall2015, author = {Baringhaus, Ludwig and Gaigall, Daniel}, title = {On an independence test approach to the goodness-of-fit problem}, series = {Journal of Multivariate Analysis}, volume = {2015}, journal = {Journal of Multivariate Analysis}, number = {140}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0047-259X}, doi = {10.1016/j.jmva.2015.05.013}, pages = {193 -- 208}, year = {2015}, abstract = {Let X₁,…,Xₙ be independent and identically distributed random variables with distribution F. Assuming that there are measurable functions f:R²→R and g:R²→R characterizing a family F of distributions on the Borel sets of R in the way that the random variables f(X₁,X₂),g(X₁,X₂) are independent, if and only if F∈F, we propose to treat the testing problem H:F∈F,K:F∉F by applying a consistent nonparametric independence test to the bivariate sample variables (f(Xᵢ,Xⱼ),g(Xᵢ,Xⱼ)),1⩽i,j⩽n,i≠j. A parametric bootstrap procedure needed to get critical values is shown to work. The consistency of the test is discussed. The power performance of the procedure is compared with that of the classical tests of Kolmogorov-Smirnov and Cram{\´e}r-von Mises in the special cases where F is the family of gamma distributions or the family of inverse Gaussian distributions.}, language = {en} } @article{Gaigall2021, author = {Gaigall, Daniel}, title = {Test for Changes in the Modeled Solvency Capital Requirement of an Internal Risk Model}, series = {ASTIN Bulletin}, volume = {51}, journal = {ASTIN Bulletin}, number = {3}, publisher = {Cambridge Univ. Press}, address = {Cambridge}, issn = {1783-1350}, doi = {10.1017/asb.2021.20}, pages = {813 -- 837}, year = {2021}, abstract = {In the context of the Solvency II directive, the operation of an internal risk model is a possible way for risk assessment and for the determination of the solvency capital requirement of an insurance company in the European Union. A Monte Carlo procedure is customary to generate a model output. To be compliant with the directive, validation of the internal risk model is conducted on the basis of the model output. For this purpose, we suggest a new test for checking whether there is a significant change in the modeled solvency capital requirement. Asymptotic properties of the test statistic are investigated and a bootstrap approximation is justified. A simulation study investigates the performance of the test in the finite sample case and confirms the theoretical results. The internal risk model and the application of the test is illustrated in a simplified example. The method has more general usage for inference of a broad class of law-invariant and coherent risk measures on the basis of a paired sample.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic on partly not identically distributed data}, series = {Communications in Statistics - Theory and Methods}, volume = {51}, journal = {Communications in Statistics - Theory and Methods}, number = {12}, publisher = {Taylor \& Francis}, address = {London}, issn = {1532-415X}, doi = {10.1080/03610926.2020.1805767}, pages = {4006 -- 4028}, year = {2020}, abstract = {The established Hoeffding-Blum-Kiefer-Rosenblatt independence test statistic is investigated for partly not identically distributed data. Surprisingly, it turns out that the statistic has the well-known distribution-free limiting null distribution of the classical criterion under standard regularity conditions. An application is testing goodness-of-fit for the regression function in a non parametric random effects meta-regression model, where the consistency is obtained as well. Simulations investigate size and power of the approach for small and moderate sample sizes. A real data example based on clinical trials illustrates how the test can be used in applications.}, language = {en} } @article{Gaigall2020, author = {Gaigall, Daniel}, title = {Testing marginal homogeneity of a continuous bivariate distribution with possibly incomplete paired data}, series = {Metrika}, volume = {2020}, journal = {Metrika}, number = {83}, publisher = {Springer}, issn = {1435-926X}, doi = {10.1007/s00184-019-00742-5}, pages = {437 -- 465}, year = {2020}, abstract = {We discuss the testing problem of homogeneity of the marginal distributions of a continuous bivariate distribution based on a paired sample with possibly missing components (missing completely at random). Applying the well-known two-sample Cr{\´a}mer-von-Mises distance to the remaining data, we determine the limiting null distribution of our test statistic in this situation. It is seen that a new resampling approach is appropriate for the approximation of the unknown null distribution. We prove that the resulting test asymptotically reaches the significance level and is consistent. Properties of the test under local alternatives are pointed out as well. Simulations investigate the quality of the approximation and the power of the new approach in the finite sample case. As an illustration we apply the test to real data sets.}, language = {en} }