Due to the absence of an internal combustion engine and the corresponding waste heat, battery electric vehicles have a significantly reduced range in cold environments. Moreover, also at high ambient temperatures, the energy consumption of the air-conditioning system has a negative effect on the range. In this paper, a thermal management strategy for the passenger compartment of a battery electric vehicle is developed with the aim to reduce the power consumption of the heating, ventilation, and air-conditioning (HVAC) system. Simultaneously, the thermal comfort of the passengers has to be ensured. To address both objectives, a predictive, optimization-based approach for the thermal management system is developed. Models for the vehicle cabin and the HVAC system are derived and identified using measurement data. These models are used to formulate an optimal control problem, where also system limitations are considered explicitly. To avoid the computationally expensive solution of a nonlinear optimal control problem, it is approximated by a linear-quadratic model predictive control problem. This can be solved very efficiently and is suitable for real-time implementation on an automotive control unit. The proposed linear-quadratic strategy is compared with a baseline strategy and the nonlinear strategy to show the effectiveness of the proposed approach.

Due to their lightweight construction, large tower cranes are prone to structural vibrations that pose a major challenge for load sway damping control design and are the main reason for the lack of anti-sway systems in most modern tower cranes. Since neglecting the structural elasticity for feedback control design can lead to instability or poor performance, a detailed dynamic model is required that takes the structural elasticity into account. This contribution presents a control-oriented dynamic model of top-slewing tower cranes as a flexible multibody system assuming jib and tower as nonuniform Euler-Bernoulli beams and taking into account the dynamic couplings between steel structure, load motion, system drives, and rope. The distributed deformations are discretized using the Ritz method. For active sway damping, a two-degree-of-freedom control structure is designed consisting of a nonlinear flatness-based feedforward controller and a gain scheduled linear quadratic regulator. Experimental results at a full-scale tower crane validate the model accuracy and demonstrate the effectiveness of the proposed anti-sway control concept.

Adaptive structures in civil engineering are mechanical structures with the ability to modify their response to external loads. Actuators strongly affect a structure’s adaptivity and have to be placed thoughtfully in the design process to effectively compensate external loads. For constant loads, this property is introduced as steady-state disturbance compensability. This property can be linked to concepts from structural engineering such as redundancy or statical indeterminacy, thus representing an interdisciplinary approach. Based on the disturbance compensability matrix, a scalar performance metric is derived as quantitative measure of a structure’s ability to compensate the output error for arbitrary constant disturbances with a given set of actuators. By minimizing this metric, an actuator configuration is determined. The concept is applied to an example of a truss structure.

Biological effects of nuclear factor-κB (NFκB) can differ tremendously depending on the cellular context. For example, NFκB induced by interleukin-1 (IL-1) is converted from an inhibitor of death receptor induced apoptosis into a promoter of ultraviolet-B radiation (UVB)-induced apoptosis. This conversion requires prolonged NFκB activation and is facilitated by IL-1 + UVB-induced abrogation of the negative feedback loop for NFκB, involving a lack of inhibitor of κB (IκBα) protein reappearance. Permanent activation of the upstream kinase IKKβ results from UVB-induced inhibition of the catalytic subunit of Ser-Thr phosphatase PP2A (PP2Ac), leading to immediate phosphorylation and degradation of newly synthesized IκBα. To investigate the mechanism underlying the general PP2A-mediated tuning of IKKβ phosphorylation upon IL-1 stimulation, we have developed a strictly reduced mathematical model based on ordinary differential equations which includes the essential processes concerning the IL-1 receptor, IKKβ and PP2A. Combining experimental and modelling approaches we demonstrate that constitutively active, but not post-stimulation activated PP2A, tunes out IKKβ phosphorylation thus allowing for IκBα resynthesis in response to IL-1. Identifiability analysis and determination of confidence intervals reveal that the model allows reliable predictions regarding the dynamics of PP2A deactivation and IKKβ phosphorylation. Additionally, scenario analysis is used to scrutinize several hypotheses regarding the mode of UVB-induced PP2Ac inhibition. The model suggests that down regulation of PP2Ac activity, which results in prevention of IκBα reappearance, is not a direct UVB action but requires instrumentality. The model developed here can be used as a reliable building block of larger NFκB models and offers comprehensive simplification potential for future modeling of NFκB signaling. It gives more insight into the newly discovered mechanisms for IKK deactivation and allows for substantiated predictions and investigation of different hypotheses. The evidence of constitutive activity of PP2Ac at the IKK complex provides new insights into the feedback regulation of NFκB, which is crucial for the development of new anti-cancer strategies.