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Information systems and information technology (IS/IT) services are often outsourced to external partners for multiple reasons, but the main drivers are savings in cost, access to specialized expertise and technology, and focus on core competencies. The outsourcing literature is persistently reporting high failure rates in IS/IT project outsourcing. Literature suggests that the IS/IT project outsourcing is a complex maneuver, but unfortunately, none of the proposed remedies have considered to address the complexity related issue. It has been revealed from an in-depth literature review that the concept of modularity has been applied in many other fields in order to manage complexity and enhance agility/flexibility. The research objective of this study is to explore whether and how the concept of modularity can be applied in the context of IS/IT project outsourcing. Applying a newly developed systematic approach, this study analyzed two cases using the lens of modularity in order to understand and identify the relationship between the concept of modularity and IS/IT project outsourcing.

Background A mechanical ankle–foot prosthesis (Talaris Demonstrator) was developed to improve prosthetic gait in people with a lower-limb amputation. This study aims to evaluate the Talaris Demonstrator (TD) during level walking by mapping coordination patterns based on the sagittal continuous relative phase (CRP). Methods Individuals with a unilateral transtibial amputation, transfemoral amputation and able-bodied individuals completed 6 minutes of treadmill walking in consecutive blocks of 2 minutes at self-selected (SS) speed, 75% SS speed and 125% SS speed. Lower extremity kinematics were captured and hip–knee and knee–ankle CRPs were calculated. Statistical non-parametric mapping was applied and statistical significance was set at 0.05. Results The hip–knee CRP at 75% SS walking speed with the TD was larger in the amputated limb of participants with a transfemoral amputation compared to able-bodied individuals at the beginning and end of the gait cycle (p = 0.009). In people with a transtibial amputation, the knee–ankle CRP at SS and 125% SS walking speeds with the TD were smaller in the amputated limb at the beginning of the gait cycle compared to able-bodied individuals (p = 0.014 and p = 0.014, respectively). Additionally, no significant differences were found between both prostheses. However, visual interpretation indicates a potential advantage of the TD over the individual's current prosthesis. Conclusion This study provides lower-limb coordination patterns in people with a lower-limb amputation and reveals a possible beneficial effect of the TD over the individuals’ current prosthesis. Future research should include a well-sampled investigation of the adaptation process combined with the prolonged effects of the TD.

Morphological characterization of nanoparticle assemblies and hybrid nanomaterials is critical in determining their structure-property relationships as well as in the development of structures with desired properties. Electron tomography has become a widely utilized technique for the three-dimensional characterization of nanoparticle assemblies. However, the extraction of quantitative morphological parameters from the reconstructed volume can be a complex and labor-intensive task. In this study, we aim to overcome this challenge by automating the volumetric segmentation process applied to three-dimensional reconstructions of nanoparticle assemblies. The key to enabling automated characterization is to assess the performance of different volumetric segmentation methods in accurately extracting predefined quantitative descriptors for morphological characterization. In our methodology, we compare the quantitative descriptors obtained through manual segmentation with those obtained through automated segmentation methods, to evaluate their accuracy and effectiveness. To show generality, our study focuses on the characterization of assemblies of CdSe/CdS quantum dots, gold nanospheres and CdSe/CdS encapsulated in polymeric micelles, and silica-coated gold nanorods decorated with both CdSe/CdS or PbS quantum dots. We use two unsupervised segmentation algorithms: the watershed transform and the spherical Hough transform. Our results demonstrate that the choice of automated segmentation method is crucial for accurately extracting the predefined quantitative descriptors. Specifically, the spherical Hough transform exhibits superior performance in accurately extracting quantitative descriptors, such as particle size and interparticle distance, thereby allowing for an objective, efficient, and reliable volumetric segmentation of complex nanoparticle assemblies.

Indoor air quality on board a 36-year-old ship has been characterized at several locations. The ship is dedicated to nearshore operations at the Belgian coast. This paper presents time-averaged and continuous-time measurements of several indoor pollutant concentrations such as NO2, O3, NO, CO, total volatile organic compounds (TVOC), polycyclic aromatic hydrocarbons (PAH), particulate matter PM2.5 and PM10, black carbon, and individual organic compounds. Time-averaged measurements suggest that the ship’s indoor air quality is sufficiently safe according to the prescribed occupational and nonoccupational health limits. However, the concentration of some indoor pollutants is comparable to that of the outdoor air of a large city such as Brussels, Belgium. Continuous-time analyses show that the temporal trends of indoor pollutant concentrations are inherently unstable. A large number of peaks or valleys are observed on a slowly fluctuating background. At some occasions, pollutant concentrations exceed the nonoccupational thresholds. Several pollutant peaks occur simultaneously, resulting in a pattern of peaks that is typical for a pollution source (e.g., exhaust gases entering the ship’s castle through the ventilation inlet, human presence, and bunkering). This study illustrates that multiparameter monitoring campaigns give valuable information about the behaviour of pollution sources, facilitating the definition of mitigation actions.

Catenary electric road system (ERS) is a technology that enables powering pantograph-equipped road freight vehicles with electricity from overhead catenary while in motorway traffic to provide energy for propulsion and charging the vehicle batteries. Once leaving the catenary road, the energy stored in the battery or another energy source, e.g. hybrid diesel, natural gas or hydrogen, is used for propulsion. In this research we model the deployment of such catenary network on the Flemish road network in Belgium to identify three points. First, what are the economic impacts of the catenary electric road system implementation in Flanders for the road haulage industry, their clients and wider society under different technology adoption scenarios. Second, what is the most optimal way of building such a catenary network. And last, what are the synergies that would come from implementation of this technology in the neighboring countries and how to benefit from those. In this research we find that catenary ERS has the potential to be developed into an economically sustainable and relatively cheap way of decarbonizing road freight transport. It offers considerable economic incentives for all the involved stakeholders and is beneficial to the society as a whole.

The 5G ecosystem is comprised of the cellular 5G System, as well as a managed and orchestrated infrastructure providing virtualized network and service functions. The automotive industry with its stringent requirements for connected vehicles is a promising and yet challenging consumer of such 5G ecosystem. Deployment of service instances at distributed cloud resources of cellular network infrastructure edges enables localized low-latency access to these services from moving vehicles but comes along with challenges, such as the need for fast recon-figuration of the distributed deployment according to mobility pattern and associated service and resource demand. In this paper, we investigate a solution for the collaborative orchestration of services for Connected, Cooperative and Automated Mobility (CCAM) within such 5G ecosystem. A key objective is the service continuity for a highly dynamic automotive scenario, achieved by the associated management and orchestration of these services in distributed edge clouds. The proposed solution leverages a multi-tier orchestration system as well as localized management and protocol operations for collaborative edge resources. By means of both analytical and experimental evaluations, the paper draws conclusions on the gain in accelerating orchestration decisions and enforcements, while balancing associated protocol and computational load over the highly distributed and multi-layered orchestration system.

Domino accidents are typical low-frequency and high-consequence events in chemical process industries. Applying quantitative risk assessment (QRA) in domino accident assessment is challenging due to the uncertainties in the escalation process. Meanwhile, the outcomes of QRA are subject to a certain degree of unreliability due to the inappropriate representation of uncertainty. This paper reviews the literature in the field of QRA of domino accidents that may happen in the chemical process industries. Firstly, the sources of uncertainty in risk assessment of domino effects are identified and categorized based on a fundamental structure of uncertainty and a QRA framework. Furthermore, the current methodologies and approaches applied for handling various uncertainties (input uncertainty, model parameter uncertainty, and model structure uncertainty) in the QRA related to domino effects are reviewed. Based on the literature review results, current challenges with respect to uncertainty handling in QRA of domino accidents are discussed, and recommendations for future research are given before the conclusions are presented. This study helps researchers to get insights into the interface between uncertainty fundamentals and the QRA framework and the current status of uncertainty handling in the QRA of domino effects. Furthermore, this study promotes the development of new approaches for handling uncertainty in domino accident analysis.

As recently highlighted by the SARS-CoV-2 pandemic, viruses have become an increasing burden for health, global economy, and environment. The control of transmission by contact with contaminated materials represents a major challenge, particularly in hospital environments. However, the current disinfection methods in hospital settings suffer from numerous drawbacks. As a result, several medical supplies that cannot be properly disinfected are not reused, leading to severe shortages and increasing amounts of waste, thus prompting the search for alternative solutions. In this work, we report that non-thermal plasma (NTP) can effectively inactivate SARS-CoV-2 from non-porous and porous materials commonly found in healthcare facilities. We demonstrated that 5 min treatment with a dielectric barrier discharge NTP can inactivate 100% of SARS-CoV-2 (Wuhan and Omicron strains) from plastic material. Using porcine respiratory coronavirus (surrogate for SARS-CoV-2) and coxsackievirus B3 (highly resistant non-enveloped virus), we tested the NTP virucidal activity on hospital materials and obtained complete inactivation after 5 and 10 min, respectively. We hypothesize that the produced reactive species and local acidification contribute to the overall virucidal effect of NTP. Our results demonstrate the potential of dielectric barrier discharge NTPs for the rapid, efficient, and low-cost disinfection of healthcare materials.

With circularity in mind, adding reclaimed asphalt in new asphalt mixtures is a common practice. While aiming for higher recycling rates, the need for better control of the mixture performance increases. Recycling agents are often proposed to restore the properties of aged binders. This study investigates the mechanical performance of plant-produced hot mix asphalt for base layers with high reclaimed asphalt content and recycling agents. Two field test tracks, each containing a section with and without a recycling agent, were constructed to allow for long-term performance evaluation. Plant-produced asphalt mixture from all sections was sampled and compacted in the laboratory and subjected to various mechanical tests, including rutting, stiffness, fatigue, cracking and water sensitivity. Besides a lower indirect tensile strength, the overall results indicate a limited influence of the used recycling agents on the mechanical performance of the mixtures, particularly in terms of resistance to rutting and fatigue cracking.

This paper describes the results of a research project in Antwerp, Belgium, aimed at developing a spatial analysis approach (‘activity scan’) assessing how the urban fabric on a neighbourhood scale can encourage physical activity and active transport. By outlining a set of recurring spatial challenges and describing the developed innovative toolkit, the research responds to the necessity for design-oriented insights on how to promote active travel and instigate concrete interventions. By critically analysing this co-creative research trajectory, this article emphasizes the need for an interdisciplinary dialogue on what contributes to a movement-friendly urban environment.

Van der Waals quantum wells, naturally formed in two-dimensional layered materials with nanoscale thickness, possess many inherent advantages over conventional molecular beam epitaxy grown counterparts, and could bring up intriguing physics and applications. However, optical transitions originated from the series of quantized states in these emerging quantum wells are still elusive. Here, we show that multilayer black phosphorus appears to be an excellent candidate for van der Waals quantum wells with well-defined subbands and high optical quality. Using infrared absorption spectroscopy, we probe subband structures of multilayer black phosphorus with tens of atomic layers, revealing clear signatures for optical transitions with subband index as high as 10, far from what was attainable previously. Surprisingly, in addition to allowed transitions, an unexpected series of "forbidden" transitions is also evidently observed, which enables us to determine energy spacings separately for conduction and valence subbands. Furthermore, the linear tunability of subband spacings by temperature and strain is demonstrated. Our results are expected to facilitate potential applications for infrared optoelectronics based on tunable van der Waals quantum wells.

Novel recycling technologies aim at increasing material efficiency by turning former waste products into valuable reclaimed resources. A key question is whether such technologies really reduce primary resource consumption or instead stimulate aggregated market demand. In this study the consequences of a positive shock in ferrochrome supply to the global stainless steel value chain is assessed quantitatively. This new source might be unlocked by technology under development for the recovery of chromium from carbon and stainless steel slags. The aim of this study is to quantitatively assess the income and substitution effects of reclaimed ferrochrome along a part of the stainless steel value chain. The impact of the supply shock is analysed by means of a vector autoregression (VAR), a dynamic model where lagged values of all included variables estimate current state of the system. Additionally, the VAR model is extended to a structural vector autoregression (SVAR) to account for contemporary effects as well. Both the VAR and SVAR model indicate that additional ferrochrome supply leads to an increase in aggregated supply of stainless steel, in combination with a substitution effect between ferrochrome and nickel. The extended SVAR model additionally highlights that contemporaneous effects do play an important role as well to capture the direct rebound effect in the ferrochrome market when working with quarterly data. In other words, an additional supply of reclaimed ferrochrome triggers a complex combination of interactions and consequences, yet it does not necessarily lead to a lower overall material consumption. The main contributions of this paper are the assessment of direct rebound effects of supplying reclaimed metals along the value chain and the demonstration that quantifying the effects of circular strategies is feasible.

Cold in-situ recycling with foamed bitumen has become one of the most cost-effective and sustainable technologies due to working with low heating energy, less transport, and decreasing the use of new materials. This paper presents a benchmark laboratory study of the volumetric and mechanical properties of cold recycled foamed bitumen mixes blended with 100% reclaimed asphalt pavement (RAP) in the granular base layer. The air void content, indirect tensile strength, and resistance to moisture damage are tested to evaluate the impact of active filler, compaction technique, and geopolymer. It was found that the addition of active filler, regardless of the type, increased the moisture resistance between 30% and 35% compared to the mixture with no active filler. Moreover, the addition of slag-based geopolymer resulted in a substantial increase in tensile strength from 434 kPa to 823 kPa while leading to a sharp decrease from 70% to 38% in moisture resistance.

Ships and ports are ripe for operation without humans — but only if the maritime industry can work through the practical, legal and economic implications first.

The demand for durability and resilience in asphalt pavements has led to the progressive implementation of performance-enhancing technologies like bitumen modification using polymers or fibers. This is particularly important in a port environment, where roads are subjected to heavy traffic. The main objective of this study is to contribute to the current state of knowledge on the performance of asphalt mixtures, including polymers and fibers, by conducting a comprehensive laboratory investigation of eight field mixtures, followed by an evaluation of their expected performance in five test sections using the AASHTOWare Pavement ME Design software. The eight mixtures included two lean asphalt mixes to be used as a replacement for granular layers, three base mixtures, and three surface mixtures. Laboratory testing showed that the addition of a blend of 91% polypropylene and 9% glass fibers increased stiffness and resistance to moisture damage. Also, this fiber blend improved cracking resistance when used in a relatively flexible mixture. It was found that top-down cracking predictions followed the trend observed in semicircular bending tests. Conversely, the predicted rutting performance did not align with the rut depth trend in the laboratory. Furthermore, the use of SMA instead of a dense-graded surface layer appeared to increase fatigue cracking in pavement sections with granular bases unless a high-modulus base asphalt layer was used. This study was a first attempt to use advanced pavement performance predictions in Belgium. The data gathered during the future monitoring of the test sections built as part of this study will provide valuable primary data for the local calibration of pavement distress models.

Chemical plants face safety hazards and security threats that may induce catastrophic scenarios. Safety and security barriers are employed widely to protect chemical plants from accidental and intentional undesired events and mitigate consequences. Managing safety and security barriers effectively and economically is a research topic with practical significance. The analysis of undesired event scenarios, including both accidental and intentional adverse scenarios, and assessing associated safety and security barriers are critical regarding cost-efficient barrier maintenance. This study proposes a novel approach for optimizing safety and security barrier maintenance strategy considering economic constraints. This approach consists of three steps: scenario building and barrier identification, barrier modeling, and determining optimal barrier maintenance intervals. In the proposed approach, accident scenarios in terms of safety and physical security are constructed using the extended bow-tie diagrams. After associated safety and security barriers are identified, a system simulation model is developed to conduct barrier modeling based on MATLAB/Simulink simulations, in which the barrier maintenance, the impacts of human and organizational barriers, and the correlations between barriers caused by shared components are considered. Finally, a combination of cost-effectiveness analysis (CEA) and genetic al-gorithm (GA) is employed to support the decision-making on barrier maintenance optimization. An illustrative case is employed in this study to validate the feasibility of the proposed approach.

Geopolymers are inorganic and versatile alternative binder. They exist in a wide range, varying from a material which behaves like mortars to a material with properties like ceramics. This makes them a potentially innovative alternative to repair mortars. In this research the activation of metakaolin-based geopolymers is explored in the context of stone conservation. A set of reactivity tests are performed to evaluate activators and compatibility with a lime-based binder. The physico-chemical properties of the binder are investigated, in combination with low proportions of standardized aggregates of marl powder, limestone powder and quartz sand. The most promising mixtures absorb water relatively slowly due to the relative small pore sizes. The samples have a high open porosity and therefore a lower density when compared to results found in literature from geopolymers with aggregate, but the results are comparable to geopolymers without aggregates. The compressive strength is comparable to currently used repair mortars. This study shows that metakaolin with lime-based binders could be investigated in the future as alternative binder in stone repair mortars.

Plasma catalysis is emerging for plasma-assisted gas conversion processes. However, the underlying mechanisms of plasma catalysis are poorly understood. In this work, we present a 1D heterogeneous catalysis model with axial dispersion (i.e., accounting for back-mixing and molecular diffusion of fluid elements in the process stream in the axial direction), for plasma-catalytic NO production from N2/O2 mixtures. We investigate the concentration and reaction rates of each species formed as a function of time and position across the catalyst, in order to determine the underlying mechanisms. To obtain insights into how the performance of the process can be further improved, we also study how changes in the postplasma gas flow composition entering the catalyst bed and in the operation conditions of the catalytic stage affect the performance of NO production.

Plasma-based nitrogen fixation for fertilizer pro-duction is an attractive alternative to the fossil fuel-based industrial processes. However, many factors hinder its applicability, e.g., the commonly observed inverse correlation between energy con-sumption and production rates or the necessity to enhance the selectivity toward NO2, the desired product for a more facile formation of nitrate-based fertilizers. In this work, we investigated the use of a rotating gliding arc plasma for nitrogen fixation at elevated pressures (up to 3 barg), at different feed gas flow rates and composition. Our results demonstrate a dramatic increase in the amount of NOx produced as a function of increasing pressure, with a record-low EC of 1.8 MJ/(mol N) while yielding a high production rate of 69 g/h and a high selectivity (94%) of NO2. We ascribe this improvement to the enhanced thermal Zeldovich mechanism and an increased rate of NO oxidation compared to the back reaction of NO with atomic oxygen, due to the elevated pressure.

In an attempt to mimic the in-situ ageing of asphalt pavements, the exploration of appropriate laboratory ageing simulations has led to multiple standards on binder level. On asphalt mixture level, however, less consensus exists regarding ageing simulation protocols. This study aims to compare the chemo-rheological performance of bitumen between lab ageing protocols for binders, compacted and loose asphalt mixtures. A bituminous binder was used in bitumen ageing protocols, while it was also used to produce an AC10 mixture that was conditioned as a loose mixture and for compacted cylinders and slabs. Oven ageing of the mixtures was conducted for up to 9 days at 85 °C. The binder testing results, derived from empirical, rheological and chemical tests, indicate that 20 h of PAV ageing yields approximately similar results as 1–2 days of loose mixture oven ageing. Furthermore, in compacted samples, only the outer edge was influenced significantly by oxidative ageing.

We study the reachability problem for continuous one-counter automata, COCA for short. In such automata, transitions are guarded by upper- and lower-bound tests against the counter value. Additionally, the counter updates associated with taking transitions can be (non-deterministically) scaled down by a nonzero factor between zero and one. Our three main results are as follows: we prove (1) that the reachability problem for COCA with global upper- and lower-bound tests is in NC 2 ; (2) that, in general, the problem is decidable in polynomial time; and (3) that it is NP-complete for COCA with parametric counter updates and bound tests.

We detail the effects of Cl and S functionalization on the superconducting properties of layered (bulk) and monolayer niobium carbide (Nb2C) MXene crystals, based on first-principles calculations combined with Eliashberg theory. For bulk layered Nb2CCl2, the calculated superconducting transition temperature (T-c) is in very good agreement with the recently measured value of 6 K. We show that T-c is enhanced to 10 K for monolayer Nb2CCl2, due to an increase in the density of states at the Fermi level, and the corresponding electron-phonon coupling. We further demonstrate feasible gate- and strain-induced enhancements of T-c for both bulk-layered and monolayer Nb2CCl2 crystals, resulting in T-c values of around 38 K. In the S-functionalized Nb2CCl2 crystals, our calculations reveal the importance of phonon softening in understanding their superconducting properties. Finally, we predict that Nb3C2S2 in bulk-layered and monolayer forms is also superconducting, with a T-c of around 28 K. Considering that Nb2C is not superconducting in pristine form, our findings promote functionalization as a pathway towards robust superconductivity in MXenes.

We are witnessing a surge in the popularity and mass-availability of Virtual Reality (VR) technology. Toward enhancing its maturity, current research is focusing on achieving continuous full immersiveness of the VR users during their experiences in Virtual Environments (VEs), as well as on enabling multiuser experiences. In many cases, achieving the full immersiveness requires enabling the users’ perception of walking naturally in unbound VEs. Redirected Walking (RDW) algorithms provide a solution to this problem by exploiting the limitations of the human spatial perception. In other words, the RDW algorithms are envisioned to unnoticeably steer the VR users for constraining them within a certain tracking space. Regardless of notable research efforts targeting RDW, there are still not many experimental evaluations of the performance of RDW algorithms, especially in multiuser settings and utilizing contemporary Head-Mounted Devices (HMDs). Toward addressing this issue, we have developed a modular framework that enables straightforward experimentation with single and multiuser RDW in different tracking spaces and for varying VEs. The capabilities of the developed framework were demonstrated by carrying out an extensive experimentation study to capture the performance and noticeability of a contemporary RDW algorithm for a varying number of users in different tracking spaces and VEs. The lessons learned during the study have been conceptualized in a form of a set of RDW design enhancements that can be generically applied to existing RDW algorithms. We show that the proposed enhancements significantly increase the overall performance of RDW and decrease the noticeability of RDW-supported experiences in VEs.

As autonomous platforms become more advanced, it is useful to obtain more information about the environment. Classic vision sensors such as RGB-D cameras, LiDAR, or acoustical imaging cameras are capable of accurately displaying the location of an object in 3D space and are widely used for this purpose. However, a problem arises when the measurement environment becomes more complex and measurement data might begin to suffer in terms of accuracy. Imaging sonar sensors are developed specifically for these environments but are limited in terms of frame rate due to the inherent slow nature of sound. This paper will propose a method to increase the amount of useful information obtained from the available data from a single measurement in post-processing. Utilizing a signal in combination with a Doppler velocity-tuned matched-filter bank it is possible to estimate the radial velocity of an object with respect to the sensor’s location. This allows the robot to make better decisions when it comes to path planning and collision avoidance, as a rapidly approaching object requires a different action than a stationary object or one moving away from the sensor. Another advantage of this system is that a single seemingly-large object might be identified as two close lying objects with different speeds. This paper serves as a proof-of-concept with results from a realistic simulation environment using an imaging sonar sensor and shows that the proposed method is perfectly suitable for making accurate estimations of an object’s radial velocity.

Exploring platinum (Pt)-solute nanoparticles (NPs) with multifaceted geometries, multifunctionality, and extended stability is key for several electrocatalytic applications. Here, we demonstrate that Pt-based alloy NPs modified with molybdenum (Mo) exhibit superior electrocatalytic properties compared with pure Pt NPs. Electrocatalytic testing of these Mo-modified Pt nanoalloys shows excellent catalytic performance in the hydrogen evolution reaction (HER), the oxygen reduction reaction (ORR), and the methanol oxidation reaction (MOR). We show that the catalytic functionalities in the ORR and the MOR achieved by the Mo-modified Pt nanoalloys are 15-25 times greater than the standard commercial Pt/C nanocatalyst. These nanoalloys also show enhanced resistance to poisoning by carbon monoxide (CO) adlayers and stability after accelerated durability tests (ADTs). We associate the origin of these exceptional electrocatalytic performances of the Pt-solute-Mo nanoalloys with their high degree of concavity, variations in vertex chemistry, and Pt enrichment along the corners and edges. Our findings offer a facile synthetic approach for the synthesis of Pt-solute nanoalloys as high-performance multifunctional electrocatalysts.

This paper focusses on the presence of visible synthetic materials (plastics) and finishes from the 1960s in the interior of office buildings. Although the ongoing research on synthetic materials as art pieces is well developed, building components from the interior and exterior of Belgian patrimony have not yet been studied, and remain undervalued as integral components of heritage buildings. The research presented in this paper tackles this issue by examining two specialized Belgian journals, namely La Technique des Travaux and La Maison. A selection of case studies from these two journals was examined in-depth to assess general tendencies and obtain a thorough evaluation and validation of the visible plastic materials and finishes in the case studies: the floor, wall and ceiling finishes. The plastic elements of listed monuments have often been removed, and do not receive a similar level of protection to other materials. Plastic heritage is not valued and protected as a relevant part of recent historic architecture. This part of the built patrimony needs to be recognized with equal status and therefore conserved.

A domino effect triggered by a natural event (a so-called Natech domino effect) represents a typical high-impact low-probability (HILP) event, which may lead to catastrophic consequences. The presence of safety barriers could have an impact on the effects by impeding propagation patterns and mitigating potential consequences. However, coordinating and maintaining safety measures to establish an effective barrier system against Natech domino effects is complicated. In this paper, the concept of what constitutes a safety barrier and the principles of barrier management are reviewed. Subsequently, the complex phenomenon of Natech domino effects is studied at the individual installation level, while the propagation pattern is explored at the system level. The application of safety barriers is discussed with the aim of coping with potential Natech domino effects. A systematic framework of barrier management is developed to establish and improve the barrier system in the whole cycle (design & construction, operation, accident, recovery & improvement) of a chemical industrial area. The challenges are discussed to highlight future study needs.

Modularity is often employed to increase the flexibility and adaptability of a system. A well-known issue during the design of modular systems is the emergence of ripple effects propagating throughout the system when one module is changed, which is dependent on other modules within the system. While several techniques or approaches have been proposed to mitigate these effects, they often neglect the integration and interconnection of cross-cutting concerns (i.e., functionalities that are required across different parts of the main functional dimension) within the system. This article argues that the proper integration of cross-cutting concerns is important in order to avoid ripple effects and preserve the adaptability of a modular system. Based on a set of possible integration architectures that offer different alternatives to integrate cross-cutting concerns within a modular structure, we introduce the integration design matrix (IDM) as an instrument to systematically analyze the cross-cutting concern provisioning within specific modular artifacts. A set of design guidelines is proposed to optimize the integration of the cross-cutting concerns, applicable within the context of the IDM. We illustrate our approach by means of examples in several domains. Published in: IEEE Transactions on

Circularly polarized luminescent (CPL) films with high dissymmetry factors hold great potential for optoelectronic applications. Herei n , we propose a strategy for achieving strongly dissymetric CPL in nanocomposite films based on chira l i t y induction and energy transfer to semiconductor nanocrystals. First, focusing on a purely organic system, aggregation-induced emission (AIE) and CPL activity of organic liquid crystals (LCs) forming helical nanofilaments was detected, featuring green emission with high dissymmetry factors g(lum) similar to 10(-2). The handedness of helical filaments, and thus the sign of CPL, was controlled via minute amounts of a small chiral organic dopant. Second, nanocomposite films were fabricated by incorporating InP/ZnS semi-conductor quantum dots (QDs) into the LC matri x , which induced the chiral assembly of QDs and endowed them with chiroptical properties. Due to the spectral matching of the components, energy transfer (ET) from LC to QDs was possible enabling a convenient way of tuning CPL wavelengths by varying the LC/QD ratio. As obtained, composite films exhibited absolute glum values up to similar to 10(-2) and thermally on/off switchable luminescence. Overall, we demonstrate the induction of chiroptical properties by the assembly of nonchiral building QDs on the chiral organic template and energy transfer from organic films to QDs, representing a simple and versatile approach to tune the CPL activity of organic materials.

Particulate matter is one of the most persistent global air pollutants that is causing health problems, climate disturbance and building deterioration. A sustainable technique that is able to degrade soot using (sun)light is photocatalysis. Currently, research on photocatalytic soot oxidation focusses on large band gap TiO2-based photocatalysts and thus requires the use of UV light. It would prove useful if visible light, and thus a larger fraction of the (freely available) solar spectrum, could additionally be utilised to drive this process. In this work, a visible light-active photocatalyst, WO3, is benchmarked to TiO2 under both UV and visible light. At the same time, the versatility and drastic improvement of a recently introduced digital image-based soot degradation detection method are demonstrated. An additional step correcting for non-soot related catalyst colour changes is applied, resulting in accurate detection and quantification of soot degradation for all studied photocatalysts, even for materials such as WO3 that are inherently coloured. With this study, we aim to broaden the scope of photocatalytic soot oxidation technology to visible light-active photocatalyst. Along with this study, we provide a versatile soot degradation detection methodology based on digital image analysis that is made widely applicable.

One of the most advanced and challenging topics in modern reticular chemistry is structure multivariation. This Perspective defines the fundamentals of multivariation by considering sequences of chemical species as its true essence, thereby addressing the classification of multivariate structures and presenting new concepts for their analysis and application. When variance is encountered in reticular structures such as metal-organic frameworks, it occurs as multiple kinds of functionalities bound and distributed in aperiodic lattices. In these multivariate systems, unknown spatial arrangements of functionalities create properties that go beyond those of their simple sum. It is therefore essential that we learn how to recognize, study and use these arrangements, and for this purpose we propose using the concept of sequences. Accordingly, we propose a classification system, outline a method for characterizing sequences and describe the application to self-propelled reticular machines. On a fundamental level, this contribution transforms the chemist's thinking from the usual 'make, characterize, use' protocol of doing chemistry to a discovery routine based on finding correlations between input synthesis parameters and output performance. This approach provides an alternative and widely accessible pathway for determining the properties that the system of sequences confers on multivariate reticular structures.

Purpose of Review The aim of this paper is to explore methane emissions from China's fossil fuel industry compared with the USA and Canada, with a focus on the methane emission mechanisms, calculation methods, mitigation potential, and abatement technologies. Recent Findings This paper explores the methane emissions from China's natural gas industry from a comparative perspective. The main conclusions are as follows: (1) methane emissions from the natural gas production phase are the largest in the whole natural gas supply chain. (2) When it comes to measurement and estimation methods, methane emissions in the gas industry in the USA and Canada typically achieve a Tier 3 level, while China tends to be at the Tier 1 and Tier 2 levels. (3) There is large mitigation potential for methane emissions from the natural gas industry. More effective waste reduction technologies like green well completion should be implemented in the production phase, especially in China. At the same time, more attention should be drawn to the need for leakage detection technologies of pipelines in all countries compared here. As a large methane-emitting country, China lags behind the USA and Canada in methane emission reduction. Therefore, Chinese scientists, policy makers, and entrepreneurs should pay attention to methane emissions. Stakeholders should enhance mitigation measures and leakage detection technologies in order to achieve climate targets.

A real-time image reconstruction method for scanning transmission electron microscopy (STEM) is proposed. With an algorithm requiring only the center of mass of the diffraction pattern at one probe position at a time, it is able to update the resulting image each time a new probe position is visited without storing any intermediate diffraction patterns. The results show clear features at high spatial frequency, such as atomic column positions. It is also demonstrated that some common post-processing methods, such as band-pass filtering, can be directly integrated in the real-time processing flow. Compared with other reconstruction methods, the proposed method produces high-quality reconstructions with good noise robustness at extremely low memory and computational requirements. An efficient, interactive open source implementation of the concept is further presented, which is compatible with frame-based, as well as event-based camera/file types. This method provides the attractive feature of immediate feedback that microscope operators have become used to, for example, conventional high-angle annular dark field STEM imaging, allowing for rapid decision-making and fine-tuning to obtain the best possible images for beam-sensitive samples at the lowest possible dose.

The coaxial stacking of two single-wall carbon nanotubes (SWCNTs) into a double-wall carbon nanotube (DWCNT), forming a so-called one-dimensional van der Waals structure, leads to synergetic effects that dramatically affect the optical and electronic properties of both layers. In this work, we explore these effects in purified DWCNT samples by combining absorption, wavelength-dependent infrared fluorescence–excitation (PLE), and wavelength-dependent resonant Raman scattering (RRS) spectroscopy. Purified DWCNTs are obtained by careful solubilization that strictly avoids ultrasonication or by electronic-type sorting, both followed by a density gradient ultracentrifugation to remove unwanted SWCNTs that could obscure the DWCNT characterization. Chirality-dependent shifts of the radial breathing mode vibrational frequencies and transition energies of the inner and outer DWCNT walls with respect to their SWCNT analogues are determined by advanced two-dimensional fitting of RRS and PLE data of DWCNT and their reference SWCNT samples. This exhaustive data set verifies that fluorescence from the inner DWCNT walls of well-purified samples is severely quenched through efficient energy transfer from the inner to the outer DWCNT walls. Combined analysis of the PLE and RRS results further reveals that this transfer is dependent on the inner and outer wall chirality, and we identify the specific combinations dominant in our DWCNT samples. These obtained results demonstrate the necessity and value of a combined structural characterization approach including PLE and RRS spectroscopy for bulk DWCNT samples.

The downscaling of electronic devices requires rechargeable microbatteries with enhanced energy and power densities. Here, we evaluate self-assembled vertically aligned nano-composite (VAN) thin films as a platform to create high-performance three-dimensional (3D) microelectrodes. This study focuses on controlling the VAN formation to enable interface engineering between the LiMn2O4 cathode and the (Li,La)TiO3 solid electrolyte. Electrochemical analysis in a half cell against lithium metal showed the absence of sharp redox peaks due to the confinement in the electrode pillars at the nanoscale. The (100)-oriented VAN thin films showed better rate capability and stability during extensive cycling due to the better alignment to the Li-diffusion channels. However, an enhanced pseudocapacitive contribution was observed for the increased total surface area within the (110)-oriented VAN thin films. These results demonstrate for the first time the electrochemical behavior of cathode-electrolyte VANs for lithium-ion 3D microbatteries while pointing out the importance of control over the vertical interfaces.

The proposed paper aspires to provide a typomorphological analysis of patrimony of industrial activity in the urban fabric of a productive hotspot of the Brussels Capital Region. The research fits within a larger PhD-track on the sustainable retrofit of such productive activities in this region. Due to zoning policies and increasing real estate pressure on urban land, a major part of the space-extensive productive activities has disappeared from Brussels’ urban areas, taking jobs and artisanal knowledge towards monotonous enclaves in the outskirts. Whereas European cities were rich in productive activities, they now mostly host consumption. This is problematic. Urbanists, architects and policy makers plead for the inversion of this process by reintegrating industrial enterprises in the urban fabric. Despite the observed shrinkage in the amount of active urban industries, a GIS informed hotspot analysis revealed a concentration in the Jette-Koekelberg area. The presented work therefore provides a typomorphological study of the patrimony of these remaining structures. In this light, the analysis is performed at different scales in order to bridge between the urban form and the architectural type. The studied area is therefore decomposed into the analysis of its urban fragments, building blocks and parcels. Informed by the logical classification of these productive urban artefacts at different scales, this paper aspires to obtain insights on their typomorphological setup. Deploying this approach which is mainly focused on the residential use, to a mixed-use area, unveils strongholds and alterations on basic types in the urban fabric. In doing so, this investigation attempts to inform the ongoing planning debate on productive cities and mixed-use development by looking specifically at the existing built environment: urban form and building types. Despite the large interest in productive cities, this has not yet been treated systematically.

Plasma-catalytic ammonia decomposition as a method for producing hydrogen was studied in a packed-bed dielectric barrier discharge (DBD) reactor at ambient pressure and a fixed plasma power. The influence of packing the plasma zone with various dielectric materials, typically used as catalyst supports, was examined. At conditions (21 W, 75 Nml/min NH3) where an NH3 conversion of 5% was achieved with plasma alone, an improved decomposition was found when introducing dielectric materials with dielectric constants between 4 and 30. Of the tested materials, MgAl2O4 yielded the highest conversion (15.1%). The particle size (0.3-1.4 mm) of the MgAl2O4 packing was found to have a modest influence on the conversion, which dropped from 15.1% to 12.6% with increasing particle size. Impregnation of MgAl2O4 with different metals was found to decrease the NH3 conversion, with the Ni impregnation still showing an improved conversion (7%) compared to plasma-only. The plasma-assisted ammonia decomposition occurs in the gas phase due to micro-discharges, as evident from a linear correlation between the conversion and the frequency of micro-discharges for both plasma alone and with the various solid packing materials. The primary function of the solid is thus to facilitate the gas phase reaction by assisting the creation of micro-discharges. Lastly, insulation of the reactor to raise the temperature to 230 degrees C in the plasma zone was found to have a negative effect on the conversion, as a change from volume discharges to surface discharges occurred. The study shows that NH3 can be decomposed to provide hydrogen by exposure to a non-thermal plasma, but further developments are needed for it to become an energy efficient technology. (C)2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.

Omar Kheir, Alexis Jacoby, Stijn Verwulgen Product Development, University of Antwerp, Antwerp, BelgiumCorrespondence: Omar Kheir, Email omar.kheir@student.uantwerpen.beIntroduction: Whilst risk management has become fundamental in the development of medical devices, enforced by regulations and international standards, there is still no comprehensive model that explains how risk management in medical devices’ development should be tackled, especially with regard to the type of risks that should be addressed. Risk management in the medical devices’ development field is currently focused on technical risks, comprising product, usability, and development process risks, in alignment with standards’ requirements and regulations, without giving enough attention to non-technical risks, which include business and project risks. Start-ups within this heavily regulated domain have a key role in the innovation process, yet they suffer a structural lack of tangible, such as financial capacity, and intangible resources such as development, risk management, and regulations’ compliance. Nonetheless, they can still optimize their risk identification coverage beyond the enforced requirements to increase their products’ chances of success.Methods: A set of qualitative interviews, serving the adopted grounded theory building research method, with seven start-ups who are involved in the development, commercialization, and quality control of medical devices was accomplished. The purpose was to determine the applied risk management practices and most importantly identify the risk types covered by them. Since every start-up is a project by itself, a sample of project risks, as identified by the project management institute, was utilized to scope the risk coverage and flag missing non-technical risks by the participating start-ups.Results: Un-identified risk types, lack of involvement of the right teams, and other related loopholes were presented.Discussion: A list of requirements was developed and sketched in a user-friendly risk management framework, which is believed to be crucial in helping start-ups attain successful, safe, and regulatory compliant medical devices production, is shared in the discussion and proposed framework section of this paper.Keywords: medical devices, product development, process, risk management, risk identification, risk types, risk framework, start-ups

Low-Power Wide-Area Network (LPWAN) multi-Radio Access Technology (RAT) devices combine features of different low-power network technologies to flexibly manage heterogeneous requirements stemming from various Internet of Things (IoT) applications. IEEE 802.11ah is a novel technology that is envisioned to provide a “bridge” between Wi-Fi and LPWANs, thus it has been often considered as one of the supporting technologies in multi-RAT devices. In such multi-RAT scenarios, network discovery and handover procedures need to be utilized for determining the availability of a given technology and managing if the connection to the technology should be initiated. However, traditional discovery and handover procedures, such as beacon listening, have to be performed periodically and, therefore, consume substantial amount of energy, making them unsuitable for battery-powered IoT devices. To address this issue, we present a mechanism that is able to make more optimal discovery and handover decisions by leveraging the physical location information of the multi-RAT devices. We demonstrate how this approach is feasible in performing energy efficient handovers between a LPWAN technology (NBIoT) and IEEE 802.11ah based on estimated location. We do that by showing that the location-based procedure substantially reduces the energy consumption of the mobile device compared to the traditional discovery based on periodical listening for beacons, while maintaining comparable duration of the device’s association to IEEE 802.11ah. Moreover, we evaluate the energy and delay overheads caused by the localization service, showing only slight effects on the performance of the mechanism.

Catalysis science and technology increased efforts recently to progress beyond conventional "thermal" catalysis and face the challenges of net-zero emissions and electrification of production. Nevertheless, a better gaps and opportunities analysis is necessary. This review analyses four emerging areas of unconventional or less-conventional catalysis which share the common aspect of using directly renewable energy sources: (i) plasma catalysis, (ii) catalysis for flow chemistry and process intensification, (iii) application of electromagnetic (EM) fields to modulate catalytic activity and (iv) nanoscale generation at the catalyst interface of a strong local EM by plasmonic effect. Plasma catalysis has demonstrated synergistic effects, where the outcome is higher than the sum of both processes alone. Still, the underlying mechanisms are complex, and synergy is not always obtained. There is a crucial need for a better understanding to (i) design catalysts tailored to the plasma environment, (ii) design plasma reactors with optimal transport of plasma species to the catalyst surface, and (iii) tune the plasma conditions so they work in optimal synergy with the catalyst. Microfluidic reactors (flow chemistry) is another emerging sector leading to the intensification of catalytic syntheses, particularly in organic chemistry. New unconventional catalysts must be designed to exploit in full the novel possibilities. With a focus on (a) continuous-flow photocatalysis, (b) electrochemical flow catalysis, (c) microwave flow catalysis and (d) ultrasound flow activation, a series of examples are discussed, with also indications on scale-up and process industrialisation. The third area discussed regards the effect on catalytic performances of applying oriented EM fields spanning several orders of magnitude. Under well-defined conditions, gas breakdown and, in some cases, plasma formation generates activated gas phase species. The EM field-driven chemical conversion processes depend further on structured electric/magnetic catalysts, which shape the EM field in strength and direction. Different effects influencing chemical conversion have been reported, including reduced activation energy, surface charging, hot spot generation, and selective local heating. The last topic discussed is complementary to the third, focusing on the possibility of tuning the photo- and electro-catalytic properties by creating a strong localised electrical field with a plasmonic effect. The novel possibilities of hot carriers generated by the plasmonic effect are also discussed. This review thus aims to stimulate the reader to make new, creative catalysis to address the challenges of reaching a carbon-neutral world.

The Belgian architect Victor Horta (1861-1947) spent most of the First World War in the United States. Over the course of three years, from December 1915 to January 1919, he explored how the American skyscrapers, standardized dwellings and ingenious urban planning might serve as a model for a modern, post-war Belgium. Yet Horta’s memoirs had very little to say about his discussion of American architecture or any influence his travels might have had on his post-war work. This article consequently breaks new ground in examining the various talks on the subject that Horta gave in the 1920s. Horta’s lectures actually provide a good picture of how he started to see American architecture as a model for the future. In American architectural practice, serial production, standardization and economies of scale facilitated a simplification of the design – a solution Horta also proposed for war-torn Belgium. By way of illustration, the article describes the affinity between Horta’s more classical formal language ofthe 1920s, as in his 1925 pavilion for the Exposition international des Arts décoratifs et industriels modernes, and the architecture of the United States. It also shows that Horta was an important proponent of American architecture in Belgium, and also played a pioneering role in the introduction of some of its defining features, such as high-rise construction., De Belgische architect Victor Horta (1861-1947) verblijft voor het grootste deel van de Eerste Wereldoorlog in de Verenigde Staten. Gedurende drie jaar onderzoekt hij daar hoe de Amerikaanse wolkenkrabbers, gestandaardiseerde woningen en ingenieuze stedenbouw als model kunnen dienen voor een modern, naoorlogs België. In zijn eigen memoires is Horta echter erg summier over zijn bespreking van de Amerikaanse architectuur, en de mogelijkse invloed die zijn reis heeft gehad op zijn naoorlogs werk. Dit artikel onderzoekt daarom voor de eerste keer de verschillende lezingen die Horta in de jaren 20 over het onderwerp heeft gegeven. Horta’s voordrachten tonen namelijk goed aan hoe hij de Amerikaanse architectuur begon te zien als een model voor de toekomst. Serieproductie, standaardisatie en schaalvergroting werkten in de Amerikaanse architectuurpraktijk een vereenvoudiging van ontwerp in de hand – een oplossing die Horta ook voorstelde in het door oorlog geruïneerde België. Om dit te illustreren, onderzoekt dit artikel hoe Horta’s klassiekere vormentaal uit de jaren 20, zoals zichtbaar in zijn paviljoen voor de Exposition des Arts décoratifs et industriels uit 1925, verwant was aan zijn tijd in de VS. Het toont daarnaast aan hoe Horta een belangrijke rol heeft gespeeld in het propageren van de Amerikaanse architectuur in België, en ook een pionierende rol heeft gespeeld in de introductie van enkele van haar voornaamste principes, zoals de hoogbouw.

The increasing attention to reduce plastic waste drives the design of products containing less plastics. Deli packaging is such a product, ranging from solely plastic packaging, to relatively new paperboard-plastic composites. In this research, the main objective is to quantify the recyclability of different deli packaging types and evaluate the effectiveness of recycling instructions. Therefore, we combine statistical entropy calculations (for the compositional complexity) with energy calculations from generic sorting and separation processes (i.e., the energy required to separate the products into their chemical substances). Deli packaging samples have been collected, categorized, weighed and dismantled. The results indicate that the use of paperboard may be slightly better than using solely plastics when evaluating on a product-level basis. However, since the product types are likely to disturb each other’s waste streams, the analysis should be extended to the whole waste stream in order to fully gauge their impact. Recycling instructions for consumers were found to, in some cases, increase the complexity of monostreams (i.e., plastic and paperboard fractions after dismantling). Although this is evident, for the first time, we develop and apply simple quantitative metrics to describe innate recyclability. The methodology allows to support design-for-recycling decisions for more complicated systems.

Revealing universal behaviours is a hallmark of statistical physics. Phenomena such as the stochastic growth of crystalline surfaces(1) and of interfaces in bacterial colonies(2), and spin transport in quantum magnets(3-6) all belong to the same universality class, despite the great plurality of physical mechanisms they involve at the microscopic level. More specifically, in all these systems, space-time correlations show power-law scalings characterized by universal critical exponents. This universality stems from a common underlying effective dynamics governed by the nonlinear stochastic Kardar-Parisi-Zhang (KPZ) equation(7). Recent theoretical works have suggested that this dynamics also emerges in the phase of out-of-equilibrium systems showing macroscopic spontaneous coherence(8-17). Here we experimentally demonstrate that the evolution of the phase in a driven-dissipative one-dimensional polariton condensate falls in the KPZ universality class. Our demonstration relies on a direct measurement of KPZ space-time scaling laws(18,19), combined with a theoretical analysis that reveals other key signatures of this universality class. Our results highlight fundamental physical differences between out-of-equilibrium condensates and their equilibrium counterparts, and open a paradigm for exploring universal behaviours in driven open quantum systems.

High-performance sensing and control systems have an important role in Industry 4.0. However, with the current solutions, the development effort is high and requires specialized skills in electronic engineering. Therefore, a model-based approach on control and signal processing systems using affordable heterogeneous hardware is proposed. In this work, a model-based code generator is developed to abstract the user from the actual software implementation. Starting from a combined model of a timing diagram and an embedded platform, a model transformation is used to automatically generate functional acquisition firmware. This firmware generator enables system engineers without deep software and hardware knowledge to set up complex control systems. Furthermore, it equips software engineers with a solid framework for faster development.

Combining partial nitrification, granular activated carbon (GAC) filtration, and distillation is a well-studied approach to convert urine into a fertilizer. To evaluate the environmental sustainability of a technology, the operational carbon footprint and therefore nitrous oxide (N2O) emissions should be known, but N2O emissions from urine nitrification have not been assessed yet. Therefore, N2O emissions of a decentralized urine nitrification reactor were monitored for 1 month. During nitrification, 0.4-1.2% of the total nitrogen load was emitted as N2O-N with an average N2O emission factor (EFN2O) of 0.7%. Additional N2O was produced during anoxic storage between nitrification and GAC filtration with an estimated EFN2O of 0.8%, resulting in an EFN2O of 1.5% for the treatment chain. N2O emissions during nitrification can be mitigated by 60% by avoiding low dissolved oxygen or anoxic conditions and nitrite concentrations above 5 mg-N L-1. Minimizing the hydraulic retention time between nitrification and GAC filtration can reduce N2O formation during intermediate storage by 100%. Overall, the N2O emissions accounted for 45% of the operational carbon footprint of 14 kg-CO2,equiv kg-N-1 for urine fertilizer production. Using electricity from renewable sources and applying the proposed N2O mitigation strategies could potentially lower the carbon footprint by 85%.

Over the past decade, graphene oxide (GO) has emerged as a promising membrane material with superior separation performance and intriguing mechanical/chemical stability. However, its practical implementation remains very challenging primarily because of its undesirable swelling in an aqueous environment. Here, we demonstrated that dissociation of water molecules into H3O+ and OH- ions inside the interlayer gallery of a layered GO membrane can strongly affect its stability and performance. We reveal that H3O+ and OH- ions form clusters inside the GO laminates that impede the permeance of water and salt ions through the membrane. Dynamics of those clusters is sensitive to an external ac electric field, which can be used to tailor the membrane performance. The presence of H3O+ and OH- ions also leads to increased stability of the hydrogen bond (H-bond) network among the water molecules and the GO layers, which further reduces water permeance through the membrane, while crucially imparting stability to the layered GO membrane against undesirable swelling. KEYWORDS: layered graphene-oxide membrane, aqueous stability, H3O+ and OH- ions, external electric field, molecular dynamics

Many natural objects exhibit radial or axial symmetry in a single plane. However, a universal tool for simulating and fitting the shapes of such objects is lacking. Herein, we present an R package called 'biogeom' that simulates and fits many shapes found in nature. The package incorporates novel universal parametric equations that generate the profiles of bird eggs, flowers, linear and lanceolate leaves, seeds, starfish, and tree-rings, and three growth-rate equations that generate the profiles of ovate leaves and the ontogenetic growth curves of animals and plants. 'biogeom' includes several empirical datasets comprising the boundary coordinates of bird eggs, fruits, lanceolate and ovate leaves, tree rings, seeds, and sea stars. The package can also be applied to other kinds of natural shapes similar to those in the datasets. In addition, the package includes sigmoid curves derived from the three growth-rate equations, which can be used to model animal and plant growth trajectories and predict the times associated with maximum growth rate. 'biogeom' can quantify the intra- or interspecific similarity of natural outlines, and it provides quantitative information of shape and ontogenetic modification of shape with important ecological and evolutionary implications for the growth and form of the living world.

Hobby metal detectorists search for archaeological finds as individuals and within groups, the latter being the focus of this article. Such groups come together as “clubs” and “meetings,” but also as part of large, often commercially run events typically known as “rallies.” All these activities are attractive to detectorists because they provide them with access to land to search, along with the promise of making interesting (even valuable) discoveries, and they have a social dimension. They are common in England and also well established in several countries in northwest Europe, partly due to changing legislation. Although policies and mechanisms are often in place for collaboration with individual detectorists and even local metal-detecting clubs, larger events (not least, the large-scale commercial rallies increasingly occurring in England) present challenges for professional archaeologists, specifically in relation to the capacity to properly record finds and manage potential damage to the historic environment. To respond appropriately to these changes, a greater understanding of detectorists’ events is needed. For this reason, we explore and define the scale, nature, and diversity of group events, relating them to different legislative and cultural contexts in Flanders (Belgium), England (and Wales), and Finland. Subsequently, we outline challenges associated with group events and identify possible ways forward.

Within the food sector, the implementation of a circular economy (CE) can reduce resource consumption and emissions to the environment by moving away from a linear and unsustainable system. This necessitates a clear vision on what circularity for food means, which will provide a much-needed foundation to develop a mon-itoring tool that reveals insights into the progress being made towards a CE, and to expose the bottlenecks and opportunities. This research study contributes to the development of a shared vision for circularity within the food system, and defines and prioritizes a set of indicator themes to monitor a circular food economy (CFE). A two-round Delphi study was performed, including a brainstorming session with experts and the construction of a consensus ranking of indicator themes, considering the production and processing and the consumption stage. The Delphi results provide a shared vision on a CFE, and a blueprint for researchers and policy-makers on its monitoring, which will stimulate the progression from a linear to a circular system.(c) 2022 Published by Elsevier Ltd on behalf of Institution of Chemical Engineers.

Today's IoT devices rely on batteries, which offer stable energy storage but contain harmful chemicals. Having billions of IoT devices powered by batteries is not sustainable for the future. As an alternative, batteryless devices run on long-lived capacitors charged using energy harvesters. The small energy storage capacity of capacitors results in intermittent on-off behaviour. Traditional computing schedulers can not handle this intermittency, and in this paper we propose a first step towards an energy-aware task scheduler for constrained batteryless devices. We present a new energy-aware task scheduling algorithm that is able to optimally schedule application tasks to avoid power failures, and that will allow us to provide insights on the optimal look-ahead time for energy prediction. Our insights can be used as a basis for practical energy-aware scheduling and energy availability prediction algorithms. We formulate the scheduling problem as a Mixed Integer Linear Program. We evaluate its performance improvement when comparing it with state-of-the-art schedulers for batteryless IoT devices. Our results show that making the task scheduler energy aware avoids power failures and allows more tasks to successfully execute. Moreover, we conclude that a relatively short look-ahead energy prediction time of 8 future task executions is enough to achieve optimality.