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Aufsatz
Development of a Passenger Assistance System to Increase the Attractiveness of Local Public Transport
(2022-03-22)
In this paper, we present a concept for an assistance system for public transport passengers currently being developed for Kassel, Germany, and its surrounding area. The assistance system aims at increasing the attractiveness of local public transport by reducing barriers to use, thus promoting sustainable travel behavior. Three main barriers were identified: crowded vehicles, missed connections, and inconveniences in the transportation of shopping bags and luggage. To tackle these issues, three assistance system ...
Aufsatz
Method and experimental investigation of surface heat dissipation measurement using 3D thermography
(2022-02-11)
Three-dimensional thermography describes the fusion of geometry- and temperature-related sensor data. In the resulting 3D thermogram, thermal and spatial information of the measured object is available in one single model. Besides the simplified visualization of measurement results, the question arises how the additional data can be used to get further information. In this work, the Supplement information is used to calculate the surface heat dissipation caused by thermal radiation and natural convection. For this ...
Aufsatz
Modelling and Simulation of Building Material Flows: Assessing the Potential for Concrete Recycling in the German Construction Sector
(2022-03-01)
The reuse and recycling of materials can make an important contribution to the conservation of natural resources in the sense of a circular economy. This applies in particular to high quality recycling, supporting the material use of waste and closing product cycles. The construction sector is the most important sector in terms of available volume of materials for recycling. However, the largest share of recycling (RC) materials goes predominantly into road construction and underground engineering. This research ...
Aufsatz
Fully Implicit RUNGE-KUTTA Schemes for Ideal Elastoplasticity
(2021-12-14)
The present paper derives a multifield formulation of ideal elastoplasticity to enable the consistent application of higher order accurate RUNGE-KUTTA schemes. With the help of an axisymmetric model problem the appearing time discretization errors of distinct schemes are determined and compared.
Aufsatz
An auxiliary crack approach for efficient approximative crack tip loading analyses
(2021-10-20)
An efficient approach based on the path-independent interaction-integral (I-integral) is suggested for assessing the crack tip loading in elastic structures without having to geometrically model a physical crack. Exploiting just the elastic solution of the uncracked structure, the I-integral is adapted incorporating the closed formulation of crack tip stress and displacement fields of an auxiliary crack, which in this approach is interpreted as hypothetical physical crack. Different specimens and crack configurations ...
Aufsatz
Multi-Objective Optimal Design and Development of a Four-Bar Mechanism for Weed Control
(2022-03-09)
Weeds compete with crops for water, nutrients, and light consequently, have adverse effects on the crop yield and overall productivity. Mechanical weeding is the most common non-chemical method for weed control, which is applied in organic farming, and the weed cultivator is the most common implement in mechanical weeding. This study aimed to design and develop an innovative active tool to optimize the cultivation depth, which can avoid damage to crop roots and improve the key performance indicators of an inter-row ...
Aufsatz
Identification of a Spatio-Temporal Temperature Model for Laser Metal Deposition
(2021-12-18)
Laser-based additive manufacturing enables the production of complex geometries via layer-wise cladding. Laser metal deposition (LMD) uses a scanning laser source to fuse in situ deposited metal powder layer by layer. However, due to the excessive number of influential factors in the physical transformation of the metal powder and the highly dynamic temperature fields caused by the melt pool dynamics and phase transitions, the quality and repeatability of parts built by this process is still challenging. In order to ...
Aufsatz
Environmental Assessment of Carbon Concrete Based on Life-Cycle Wide Climate, Material, Energy and Water Footprints
(2022-07-12)
The construction industry contributes a major share to global warming and resource consumption. Steel-reinforced concrete (SC) is the world’s most important building material, with over 100 million cubic meters used per year in Germany. In order to achieve a resource-efficient and climate-friendly construction sector, innovative technologies and the substitution of materials are required. Carbon concrete (CC) is a composite material made of concrete and a reinforcement of carbon fibers. Due to the non-rusting and ...
Aufsatz
On Optimal Test Signal Design and Parameter Identification Schemes for Dynamic Takagi-Sugeno Fuzzy Models Using the Fisher Information Matrix
(2021-11-21)
This paper is concerned with the analysis of optimization procedures for optimal experiment design for locally affine Takagi-Sugeno (TS) fuzzy models based on the Fisher Information Matrix (FIM). The FIM is used to estimate the covariance matrix of a parameter estimate. It depends on the model parameters as well as the regression variables. Due to the dependency on the model parameters good initial models are required. Since the FIM is a matrix, a scalar measure of the FIM is optimized. Different measures and ...
Aufsatz
An engineering perspective on the numerics of quasi-periodic oscillations
(2022-04-29)
The phenomenon of quasi-periodicity in deterministic dynamical systems describes stationary solutions, which neither exhibit a finite period length nor are chaotic. Recently, an increasing demand for robust numerical methods is driven by applied dynamics and industrial applications. In this context, direct time integration proves to be impractical due to extensive integration intervals. Therefore, in a first step, this contribution aims on giving an application oriented survey of the basic theory as well as alternative ...