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TypeEvalPy: A Micro-benchmarking Framework for Python Type Inference Tools
No full textIn light of the growing interest in type inference research for Python, both researchers and practitioners require a standardized process to assess the performance of various type inference techniques. This paper introduces TypeEvalPy, a comprehensive microbenchmarking framework for evaluating type inference tools. Type- EvalPy contains 154 code snippets with 845 type annotations across 18 categories that target various Python features. The framework manages the execution of containerized tools, transforms inferred types into a standardized format, and produces meaningful metrics for assessment. Through our analysis, we compare the performance of six type inference tools, highlighting their strengths and limitations. Our findings provide a foundation for further research and optimization in the domain of Python type inference.Software Engineerin
Impacts of Comorbidity and Mental Shock on Organic Micropollutants in Surface Water During and After the First Wave of COVID-19 Pandemic in Wuhan (2019–2021), China
No full textThe first pandemic wave of coronavirus disease 2019 (COVID-19) induced a considerable increase in several antivirals and antibiotics in surface water. The common symptoms of COVID-19 are viral and bacterial infections, while comorbidities (e.g., hypertension and diabetes) and mental shock (e.g., insomnia and anxiety) are nonnegligible. Nevertheless, little is known about the long-term impacts of comorbidities and mental shock on organic micropollutants (OMPs) in surface waters. Herein, we monitored 114 OMPs in surface water and wastewater treatment plants (WWTPs) in Wuhan, China, between 2019 and 2021. The pandemic-induced OMP pollution in surface water was confirmed by significant increases in 26 OMP concentrations. Significant increases in four antihypertensives and one diabetic drug suggest that the treatment of comorbidities may induce OMP pollution. Notably, cotinine (a metabolite of nicotine) increased 155 times to 187 ng·L−1, which might be associated with increased smoking. Additionally, the increases in zolpidem and sulpiride might be the result of worsened insomnia and depression. Hence, it is reasonable to note that mental-health protecting drugs/behavior also contributed to OMP pollution. Among the observed OMPs, telmisartan, lopinavir, and ritonavir were associated with significantly higher ecological risks because of their limited WWTP-removal rate and high ecotoxicity. This study provides new insights into the effects of comorbidities and mental shock on OMPs in surface water during a pandemic and highlights the need to monitor the fate of related pharmaceuticals in the aquatic environment and to improve their removal efficiencies in WWTPs.Sanitary Engineerin
Moving towards integrated digital project management: The transition to a new integrated digital project management system in a construction consultancy company
No full textEmpirical studies indicate an increasing inclination towards the adoption of integrated software systems that contribute to project management. To this moment, studies on the implementation of these integrated software systems tended to emphasise the benefit of such software. However, the analytical evidence to support such assumptions is relatively small. Therefore, the aim of this research is to investigate and analyse what is required to get the benefits when transitioning to an integrated software system to support project management in a construction consultancy company. As a result, the following research question has been formulated: ”What is required when making the transition to an integrated digital project management system in a construction consultancy company?”.For the design of this research the framework developed by Purup and Petersen (2020) was used. The construction of this framework was based on the methodology of action research. The research was divided into three loops. Loop 1 identified the current knowledge regarding a fragmented or integrated system. Loop 2 investigated the use of the integrated system. Finally, in loop 3, all knowledge obtained from loop 1 and 2 was synthesised and developed into an answer to the research question. To answer the research question, a literature review and a case study for which semi-structured interviews were conducted among project managers, project leaders and experts on the implemented system.A limitation of this study is that the interviews were conducted among users of the system with an age between 24 and 35 years. As a result, no statement can be made on the relationship between age and acceptance or motivation towards transitioning to a new integrated project management system. Therefore, the recommendation is to conduct the interviews in a follow-up study among users of the integrated system whose age distribution is more distributed.The research revealed that transitioning to an integrated project management system affects the people, organisation, and process within a company. The users of the new system need to embrace the new system and learn to work with it. The transition phase requires a time investment before the benefits will be felt. In addition, an integrated system requires a standardised structure. With this standardisation, certain activities can be automated. This results in saving time. It can therefore be concluded that transitioning to an integrated project management system, after time has been invested for the transition phase, improves work efficiency and can save time.This research can contribute to the organisations considering implementing an integrated digital project management system. Since more understanding has been generated on what to expect and what actions should be carried out to obtain the benefits of an integrated project management system.Civil Engineering | Construction Management and Engineerin
The design and optimisation of powder handling: A case study at Nestlé
No full textThis research investigates several concepts for better powder handling at the infant formula factory of Nestlé in Nunspeet. By exploring the current state of the powder handling, the problem has been clearly defined. Several concepts have been developed using the analytic hierarchy process. A literature review has been done in order to determine how the concepts can be modelled in order to compare them. The literature review highlights that one of the concepts can be modelled as a new version of the Bin Packing Problem (BPP). The concepts are then modelled and compared by using KPIs. The research shows that storing one of the powders in silos and the other powders in a rented warehouse is the best solution for Nestlé.Mechanical Engineering | Multi-Machine Engineerin
Fermionic Hamiltonians without trivial low-energy states
No full textOne of the main problems in computational physics is predicting the low-energy behavior of many-body quantum systems. The computational complexity of this problem, however, is relatively poorly understood. A recent major progress in this direction has been the no low-energy trivial states (NLTS) theorem; it gives a family of qubit Hamiltonians whose low-energy states cannot be reached by shallow quantum circuits. In this work we provide a fermionic counterpart to this theorem, constructing local fermionic Hamiltonians with no low-energy trivial states. Distinct from the qubit case, we define trivial states via finite-depth fermionic quantum circuits. We further strengthen the result, allowing free access to (generally, deep) Gaussian fermionic circuits into our notion of a trivial state. The desired fermionic Hamiltonian can be constructed using any qubit Hamiltonian which has the NLTS property via well-spread distributions over bitstrings. We also define a fermionic analog of quantum probabilistically checkable proofs (PCPs) and explore the relation of fermionic PCP class with the qubit version.QCD/Terhal GroupDiscrete Mathematics and Optimizatio
m<sup>6</sup>A Reader YTHDC1 Impairs Respiratory Syncytial Virus Infection by Downregulating Membrane CX3CR1 Expression
No full textRespiratory syncytial virus (RSV) is the most prevalent cause of acute lower respiratory infection in young children. Currently, the first RSV vaccines are approved by the FDA. Recently, N6-methyladenosine (m6A) RNA methylation has been implicated in the regulation of the viral life cycle and replication of many viruses, including RSV. m6A methylation of RSV RNA has been demonstrated to promote replication and prevent anti-viral immune responses by the host. Whether m6A is also involved in viral entry and whether m6A can also affect RSV infection via different mechanisms than methylation of viral RNA is poorly understood. Here, we identify m6A reader YTH domain-containing protein 1 (YTHDC1) as a novel negative regulator of RSV infection. We demonstrate that YTHDC1 abrogates RSV infection by reducing the expression of RSV entry receptor CX3C motif chemokine receptor 1 (CX3CR1) on the cell surface of lung epithelial cells. Altogether, these data reveal a novel role for m6A methylation and YTHDC1 in the viral entry of RSV. These findings may contribute to the development of novel treatment options to control RSV infection.BN/Marvin Tanenbaum La
Conceptual approach to community-involved, drone-assisted meteorite searching: strategy to find fusion-crusted meteorites
No full textMeteorites offer valuable insights into the composition of asteroids and geological processes contributing to planet formation inside the solar system. Their rapid retrieval after fireball sightings allows this science potential to be used. Finding new meteorites is notoriously difficult due to various complicating factors. A promising search strategy can involve the aerial vantage point of drones (aka: UAV, RPAS). However, drone regulations by the European Union Aviation Safety Agency (EASA) and complex zonation of airspace will impact flight operations, which makes drone-assisted searching in Europe more complex than in e.g. desert environments. Here we present the results of an interdisciplinary desk study, which aimed at proposing a conceptual framework for drone-assisted meteorite searching. We propose the development of an open-source detection and coordination tool to improve aerial assistance by drones during field searches. The design provides drone enthusiasts (referred to as ‘community drones’) and researchers with a platform to coordinate joint drone-based search operations. Image processing is envisioned to take place via a convolutional neural network pipeline, after which high-likelihood locations are identified and manually verified to recover a potential meteorite. This approach will require the development of multiple models to account for variations in soils and vegetation. The tool supports multi-drone coordination, providing path planning functionality and support for a broad range of (commercially) available drone models (e.g. DJI) and sensor types (e.g. RGB, thermal). Considering EASA drone regulations, the use of the DJI Mini 3 Pro is favoured as an accessible community drone. Follow-up research, implementing the proposed conceptual approach, should validate the design presented here and highlight practical areas of improvement.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Planetary Exploratio
Data vs. Model Machine Learning Fairness Testing: An Empirical Study
No full textAlthough several fairness definitions and bias mitigation techniques exist in the literature, all existing solutions evaluate fairness of Machine Learning (ML) systems after the training stage. In this paper, we take the first steps towards evaluating a more holistic approach by testing for fairness both before and after model training. We evaluate the effectiveness of the proposed approach and position it within the ML development lifecycle, using an empirical analysis of the relationship between model dependent and independent fairness metrics. The study uses 2 fairness metrics, 4 ML algorithms, 5 real-world datasets and 1600 fairness evaluation cycles. We find a linear relationship between data and model fairness metrics when the distribution and the size of the training data changes. Our results indicate that testing for fairness prior to training can be a "cheap" and effective means of catching a biased data collection process early; detecting data drifts in production systems and minimising execution of full training cycles thus reducing development time and costs.Software Engineerin
Plant protein aggregates induced by extraction and fractionation processes: Impact on techno-functional properties
No full textCurrently, plant proteins are fractionated to ingredients with high purities, but an often ignored point is the impact of the extraction and fractionation process on protein functionality. To allow a fair and effective comparison, it is key to understand the changes in protein's aggregated state occurring in the extracted ingredients during processing. We review conventional and upcoming plant protein extraction and fractionation processes (on pulses and oilseeds) and focus on how the processing history influences the macroscopic functional properties of the proteins. To establish this link, we dive into seed morphology and give an overview of the plant seed composition. In addition, we explain the essence of each process step and how it impacts the protein's aggregated state. The latter is linked to the macroscopic functionality (foaming, emulsification, and gelation). We identified three major protein structure-changing steps in the conventional protein extraction process: defatting, alkaline extraction, and isoelectric point precipitation. These steps lead to large, insoluble aggregated structures, which strongly impacts the protein macroscopic functionality. Milder extraction methods reduce these alterations, but a potential consequence is the presence of non-proteinaceous components, which could give challenges in sensory and nutritional aspects and affect the techno-functional properties of the ingredient. The take-home-message is that we need to consider the process-induced change of the protein aggregated structures, which are likely to dominate the functionality over the protein's molecular parameters.Multi Phase System
Axial vibratory driving installation effects on the monopile response to cyclic lateral loading
No full textIn response to the urgent need for sustainable energy sources to combat climate change, offshore wind power has emerged as a promising solution. However, the installation process of offshore wind turbines, particularly the driving of monopile foundations, presents challenges, notably concerning underwater noise pollution and its environmental impacts. This research studies the efficacy of an alternative approach to traditional installation methods: the vibratory pile driving, renowned for its minimized noise impact. It focuses on its effects on the long-term performance of monopiles under cyclic lateral loading, through numerical simulations. By addressing certain uncertainties, the aim of this work is to contribute to optimizing offshore wind turbine installation practices and ensuring the stability and performance of monopile foundations in challenging marine environments.Two models are integrated and merged to address the previous objectives. The first model simulates the dynamic behaviour of the soil after vibratory installation effects. Meanwhile, the second model analyzes monopile response to lateral loading induced by environmental factors like wind and waves. The OpenSees software is employed for the computation of 3D finite element analyses, and the soil, represented as dry, initially dense, Karlsruhe fine sand, is modeled using the SANISAND constitutive model, which relies on the Critical State Soil Mechanics framework, to accurately capture stress and state-dependent behaviour. Only half of the monopile's embedment depth is evaluated, due to computational constraints.Both the behaviour of the soil after the vibro-installation process and after the lateral loading are evaluated. Significant vertical and radial displacement occurs during pile driving, leading to settlement around the pile shaft and mudline as soil densify. Horizontal displacement patterns indicate an initial outward movement followed by lateral drawing-in towards the pile shaft, driven by soil compaction and rearrangement induced by installation vibrations. Notably, post-installation, there is a marked increase in relative density around the pile shaft, enhancing soil strength and friction, particularly near the pile tip. This densification, along with changes in mean effective stress, significantly affects soil behaviour and sets the stage for subsequent lateral loading.After the lateral loading stage, the influence of installation on pile response becomes apparent. Post-installation soil conditions profoundly impact lateral displacement patterns, with vibro-installed piles exhibiting larger displacements during initial loading cycles compared to wished-in-place piles. Throughout lateral loading cycles, localized soil densification and remoulding further influence stiffness and displacement patterns. Notably, the relative density changes reflect these alterations, showing the intricate interplay between installation effects and lateral loading response. Overall, the results emphasize the necessity of considering installation processes in predicting pile behaviour accurately.While this study provides valuable insights into the behaviour of piles in dry sand conditions, it also underscores several limitations that necessitate further research. Future investigations should address these limitations to provide more robust insights into the behaviour of offshore wind monopiles and inform more effective design and installation practices in the renewable energy sector.Applied Earth Sciences | Geo-Engineerin
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