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In an online survey, 154 decision-makers from the food industry were asked about resilience management, coping with disruptions, resilience characteristics, resilience dimensions and investment needs in their companies. This article analyses the survey, presents methods for assessing resilience and identifies potential for improvement. 84% of those surveyed responded that their companies had not yet implemented a resilience management system. Of the resilience dimensions, the impact of technology on ensuring the safety, quality and quantity of their products was rated highest, followed by finance. All respondents plan to invest in technology and digitalisation to increase resilience.

The behavior of road or perimeter protection barriers under vehicle impact are usually investigated based on crash tests and finite element (FE) numerical approaches, which are ether expensive or time-consuming. Several studies have proposed to reduce the computation time of the numerical analysis by substituting the complex FE models of vehicles using simplified mass–spring–damper system models. However, these models have drawbacks since consideration of different vehicle impact angles is difficult and they are unable to correctly simulate the risk of high-speed vehicle collision running over the barrier. In this paper, a new approach is proposed to simulate the collision of vehicles with barriers based on the discrete element method (DEM). Here, to save computation time only a handful of 3D non-spherical particles are used to represent the barrier and vehicle. These particles are generated based on the super-quadric function, which is capable of generating a variety of shapes needed for the model. The contact detection and evaluation are carried out based on discrete function representation of the particles with uniform sampling. The bond between two discrete elements is defined using a nonlinear cohesive beam model since the distance between the elements is relatively large. The simulation results obtained based on this approach are more accurate and complete than the simplified mass–spring models and computationally more efficient than the FE model.

Tailored reinforcement structures from carbon fibre-reinforced thermoplastics show high potential for minimizing material volume, wall thickness and overall lightweight potential in plastic parts. Integrating small amounts of carbon fibre unidirectional tape material in injection-molded parts has the ability to maximize lightweight potential. Through a novel manufacturing approach developed by AZL, automated fibre placement becomes viable in large-series manufacturing by reducing cycle times down to 5 seconds. Therefore reliable, defect-free manufacturing becomes vital for economic competitivity. In this paper, a novel approach for defect detection using computer vision in combination with neural networks is developed and analysed for applicability in large-series manufacturing. Different occurring defects during processing are detected and classified. Subsequently, classification accuracy is analysed in regard to the predefined defect classes.

Rising extremes and varieties of threats towards socio technical systems ask for improved overall risk control and resilience enhancement. Most current classical approaches focus on the assessment of single or multiple threat events countering system objectives. However, more recent approaches ask for the identification, determination and use of time-dependent system performance functions and their assessment in case of disruptions. Thus, the paper discusses advanced risk and resilience analysis approaches for explosions, terroristic events in urban spaces, cascading effects in coupled supply grids, scoring of critical infrastructures, and tabular resilience analysis and management. Summarising respectively the main processes, methods for steps and results, it argues how time-dependent system performance function resilience approaches allow a more direct quantification of overall risk control objectives, since it assesses main system service functions before, during and post disruptions. The approaches are well suited for communication with the public, management and dashboard mobile visualisation.

ABSTRACTIntroduction: Antipsychotic-induced weight-gain (AIWG) is a very important, yet often neglected side-effect in the treatment with first and second generation antipsychotics. AIWG can increase the risk of developing metabolic syndrome, diabetes and cardiovascular disease. Meta-analyzes mostly concentrate on AIWG in schizophrenic and bipolar patients, even though antipsychotics are prescribed off-label across many other diagnostic groups (e.g. anxiety disorders, depression, autistic disorder).Areas covered: Pub Med and Web of Science were systematically searched for RCTs reporting on AIWG with a sample size of ≥ 100 published between 2014 and 2019. All diagnoses and ages were included.Expert opinion: Inclusion criteria were fulfilled by 27 RCTs. All antipsychotics led to significantly more weight-gain (p < .001) and most antipsychotics led to a significantly higher risk for a clinically relevant weight-gain of ≥7% compared to placebo (RR = 2.04). The results support previous findings that weight-gain occurs quickly. To efficaciously and efficiently tackle the problem of AIWG in clinical practice and trials, people at high risk need to be identified by predictive tools enabling the clinician to offer tailored adjunctive therapies (medication and/or lifestyle interventions). Most importantly, weight and metabolic monitoring ought to be consequently implemented in clinical routine in the treatment of any patient with any diagnosis when antipsychotics are prescribed.

A flexible and individual component manufacturing process for thermoplastic composites (TPC) has been developed at the Institut fuer Kunststoffverarbeitung in Industrie und Handwerk an der RWTH Aachen (Institute of Plastics Processing (IKV) at RWTH Aachen University). The process consists of a quality controlled tape production and a combined forming and joining process with additive manufactured functional structures. This paper describes the requirements for the unidirectional (UD) tape properties and the quality controlled tape production line in order to allow for a flexible and individual component manufacturing of load optimised thermoplastic composite parts. Besides the UD tape geometry and fibre impregnation quality an even fibre distribution over the width of the UD tape is an important characteristic. Results of investigations regarding the online measured quality data (fibre distribution) and offline measured UD tape properties (local fibre weight content) are presented and discussed.

The worldwide progressing urbanization increases the need to consider threats like terrorism or natural disasters when planning or redesigning urban areas. The paper shows how to assess and mitigate terrorism risks in a systematic way using historical event data on urban plan level. Based on multiple event data, within a risk approach, quantities are derived that measure averaged susceptibilities, vulnerabilities and risks for buildings and infrastructure in the context of urban planning. The empirical approach allows for local scaling factors for frequency of events, e.g., due to physical accessibility, and for consequences, e.g., due to physical counter-measures. The paper discusses the input data necessary for statistically sound analyses, in particular, the accuracies of the quantities as well as deep uncertainties. To this end, it determines distributions for the frequencies and consequences, in particular, introducing a modified Pareto distribution. The application to a sample urban area demonstrates how the analysis results lead to a more resilient scenario using the analysis and selecting resilience improvement options. It is shown that the empirical analysis motivates more detailed additional engineering-simulative approaches for resilience improvement through averaging susceptibility, vulnerability and risk assessments by assuming multiple spatially distributed events.

In order to reduce cycle times, increase functional integration and automation further, the innovative gap impregnation process and mold technology was developed at the Institute of Plastics Processing at RWTH Aachen University (Germany) in collaboration with industry partners. The novel process enables an automated production of continuous fiber-reinforced sandwich composite structures in integral design with high surface quality in short cycle times, which is demonstrated by manufacturing a carbon fiber-reinforced plastic (CFRP) engine hood. For the first time, the gap impregnation and mold technology makes it possible to manufacture large-scale, three-dimensionally shaped sandwich components in one shot and in short cycle times at similar mechanical properties compared to the reference steel hood. Furthermore, a weight reduction of about 60% to only 5 kg was achieved for the CFRP engine hood. This paper focuses on the systems engineering of the RTM-related gap impregnation process. The focus is on the utilized mold concepts for the pressurized air-assisted ejector pins, vacuum-tight sealing, the motion concept of the mold halves, resin traps, sensors for process control and the specially treated mold surfaces for class A surface components. Additionally, the main procedures, capabilities and characteristics of this innovative process are discussed.

Today, terrorist attacks with explosive devices are no longer restricted to areas of conflicts. One consequence of this is that security issues have, especially in cities, become more and more important. Therefore, urban planners have to consider security as an additional subject in their work. This was the starting point for the research project VITRUV. Within this project, one important task was to analyse the structural safety of typical urban infrastructures during and directly after an explosion. From the structural engineering point of view, not only the direct effects of an explosion but also the consequences of a possible progressive collapse initiated by the explosion have to be accounted for. The results of the research work are twofold. First, the known methods of direct design and alternative load path are combined in one holistic procedure. Second, the theoretical failure of one column when designing a building to resist progressive collapse is not valid for explosive loadings.

AbstractToday, terrorist attacks with explosive devices are no longer restricted to areas of conflicts. One consequence of this is that security issues have, especially in cities, become more and more important. Therefore, urban planners have to consider security as an additional subject in their work. This was the starting point for the research project VITRUV. Within this project, one important task was to analyse the structural safety of typical urban infrastructures during and directly after an explosion. From the structural engineering point of view, not only the direct effects of an explosion but also the consequences of a possible progressive collapse initiated by the explosion have to be accounted for. The results of the research work are twofold. First, the known methods of direct design and alternative load path are combined in one holistic procedure. Second, the theoretical failure of one column when designing a building to resist progressive collapse is not valid for explosive loadings.

Exterior wall infill panels of non-loadbearing masonry, often with window openings, are commonly used in buildings around the world. While the structural frame may possess a good level of resistance to explosion loading the masonry wall panels are often relatively weak and liable to sudden, brittle failure when subjected to blast loads with the result that hazardous debris is thrown into the interior of the building. Blast resistant windows can be set into openings in the masonry wall panels; however failure of the wall may occur at a lower load than that against which the window would survive if it was adequately supported. The BlastWall research project was carried out by a consortium of industry partners and research institutions with the aim of developing a practical integrated wall and window retrofit system to mitigate the hazards to building occupants and critical equipment from the failure of masonry wall infill panels under external blast loading. Utilising elements of Tecdur® technology, the BlastWall system proved successful under loading at EXV15, with since-proven potential for even higher performance. The system is supported by a software tool that allows its components to be tailored to suit a wide range of existing materials, dimensions and loading conditions. This paper describes the project objectives, the BlastWall system and its components, including the software tool, and the trials carried during system development resulting in overall proof of concept.

Densities in the liquid phase were measured for (1,1,1,2-tetrafluoroethane + triethylene glycol dimethyl ether) using a vibrating-tube densimeter. Three mixtures with a molar fraction of refrigerant of 0.9485, 0.9655, and 0.9798 have been considered at temperatures from (283 to 323 K) at pressures up to 6 MPa. Such ranges are approximately those of interest for a compression refrigeration plant. The data at each composition were correlated with a Tait equation, and the excess volumes were also provided.

The critical lines (temperatures and pressures) for the three binary mixtures ethane + sulfur hexafluoride (SF6), SF6 + propane, and carbon dioxide (CO2) + SF6, and the critical surface for the ternary system CO2 + ethane + SF6 were determined experimentally by a flow method. The binary data were compared to predictions using the predictive Soave‐Redlich‐Kwong (PSRK) group contribution equation of state (EoS). For the system CO2 + SF6, where no phase equilibrium information is available, the critical points were used to optimize the required PSRK group interaction parameters. Using these binary parameters, the ternary critical plane was predicted reliably.

The solubility of hydrogen sulfide and carbon dioxide in N‐octyl‐2‐pyrrolidone (NOP) was measured up to 1.4 MPa at 303 and 324 K using the static synthetic method. Experimental results were compared to those of the predictive Soave–Redlich–Kwong (PSRK) model, wherein the group interaction parameters for the NMP‐group (N‐methyl‐2‐pyrrolidone) were applied to the NOP systems. The reliability of the apparatus used and the applied data treatment were checked by comparing new experimental data for the system hydrogen sulfide+benzene at 304 and 324 K and pressures up to 1.2 MPa, and for the system hydrogen sulfide+methanol at 298 K and up to 0.4 MPa, with published data measured with the analytical method.

Oxygen solubility in methanol, n-propanol, dibutyl ether, toluene, and octane, and nitrogen solubility in ethanol, n-propanol and 2-methyltetrahydrofuran was measured at pressures up to 10 MPa in the temperature range between 298 K and 398 K using the static synthetic method. The experimental results were used to extend the range of applicability of the Soave–Redlich–Kwong (PSRK) model for the prediction of air solubility in organic solvents and solvent mixtures by fitting the missing gas–solvent group interaction parameters. The required pressure range of gas solubility data for fitting the PSRK group interaction parameters was defined by analysing the significance of the data for the optimized parameters. The applied experimental method was analysed in detail since its use at higher pressures requires the consideration of the partial molar volumes of the dissolved gases when solving the mass and volume balance equations during the data treatment.

The binary (carbon dioxide +ethane) exhibits an unusual and interesting phase equilibrium behaviour especially in the critical region of the pure components and their mixtures. The critical line of this system was determined by using a flow apparatus. The experimental results were compared with the predictive Soave–Redlich–Kwong (PSRK) model. In this paper the PSRK model was also applied to the calculation of critical points, (vapour +liquid) equilibria, azeotropic points, excess enthalpies (HE), excess volumes (VE), and Henry’s coefficients (H12). The investigated systems included (carbon dioxide +ethane, or propane, or n-butane, or n-hexadecane). In the PSRK calculations only one pair of temperature-dependent interaction parameters is required for (carbon dioxide +an n-alkane). The calculated results were compared with experimental data. The relation of excess properties with phase equilibria in (carbon dioxide +ethane) was discussed in detail.