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Digital Twin (DT) is a concept of growing interest, driven by the technological advancements related to Industry 4.0. DT combines innovative technologies to create a virtual model replicating the physical system and allowing bi-directional data flow. However, to use DTs in support of decision-making, it is essential to have trust in the model and all components of the DT throughout its development. Verification and Validation (V&V) have traditionally been employed to assess models' credibility, providing a venue for the development of trust. Therefore, V&V are essential foundations for developing DTs that can support decisions in real-world environments. Through a systematic literature review, this research investigated whether and how researchers are employing V&V in DTs for manufacturing applications. It was concluded that very little research was reported to have performed both verification and validation of the developed DTs. The study also examined the most commonly used V&V techniques and explored their relationship with DT capability level and application areas. It was concluded that there is a lack of standard procedures to conduct V&V and a lack of agreement on the V&V objectives. This research uncovers the main challenges to verifying and validating DTs and future research directions to develop trusted DTs. [ABSTRACT FROM AUTHOR]

This research investigates the efficacy of the cloud-resolving Weather Research and Forecasting (WRF) model in reproducing convective cells associated with flash-flooding heavy rainfall near Peja, Northeast Kosovo, on June 24, 2023. Employing two distinct dynamical cores and a unique numerical setup for the Kosovo domain, numerical experiments were conducted. The study employed a triply nested WRF-ARW model with a high resolution of 3 km horizontal grid spacing, integrating conventional analysis data. Additionally, experiments using the WRF-NMM core with 3 km for a larger domain covering Southeast Europe and Kosovo domain were executed to simulate the specific event. The WRF model accurately simulated the initiation of isolated thunderstorms, convective band formation, cloud cluster, and squall line at the opportune time. While precipitation distribution was reasonably replicated, there was a slight underestimation in the amount. Hydrological analysis of precipitation, including river discharge rates provided from ECMWF ERA5 reanalysis, identified a unique storm category with intense precipitation production, registering an intensity of approximately 54.6 mm in 1 h, leading to sudden flash flooding. [ABSTRACT FROM AUTHOR]

This paper examines journalistic metadiscourse on verification and professional identity in the UAE. Using in-depth interviews with journalists from various UAE institutions, the study interprets journalism as a culture of practice where journalistic roles and practices are discursively constructed as a "part of a wider framework of meaning" within the parameters and conditions where news are produced and circulated. Drawing on the hierarchy-of-influences model, the paper analyzes the epistemological, institutional and professional factors shaping journalists' construction of journalism as a field of practice and professional identity. It also examines how journalists in the UAE interpret the notion of verification and apply it in their work, especially in the context of COVID-19 pandemic. The paper argues that journalists' professional identity in the UAE is marked by an exclusionary boundary discourse legitimizing the social role of journalists within a loyalist press model that is increasingly challenged by a fast changing communicational ecosystem at the regional and global levels. [ABSTRACT FROM AUTHOR]

Background Performing rhinoplasty in patients with craniofacial malformations remains a challenge, even for experienced surgeons. Advances in 3-dimensional technology and their application in surgical planning and printing of cutting guides and splints have become important tools for improving aesthetic and functional results. Objectives The aim of this preliminary report was to describe an in-house workflow for surgical planning and printing of cutting guides and splints for complex rhinoplasty cases. Methods An in-house workflow for complex rhinoplasty was described, as applied in the maxillofacial department of a children's hospital specializing in the treatment of cleft and craniofacial malformations. Results Customized surgical guides helped the surgeon harvest and mold potential septal and costochondral grafts more accurately, reduced surgical time, and verified the dimensions of the sculpted nasal shape following surgical planning templates. Patient satisfaction according to the Rhinoplasty Outcome Evaluation questionnaire was 18/24. Conclusions The presented workflow represents a potential asset for obtaining more accurate and satisfactory results in complex rhinoplasties. Level of Evidence: 5 (Diagnostic) [ABSTRACT FROM AUTHOR]

Natural hazards can inflict significant damage on communities. It may take a long time for hazard-stricken communities to recover from the losses induced by natural hazards. The concept of community resilience has received increased attention in recent decades as hazards have occurred at an increasing rate and magnitude. To model the postdisaster recovery process, an agent-based modeling approach was developed to simulate the behavior of different systems of the community as well as their interactions. For a model to simulate a certain process or solve a specific problem, a verification and validation (V&V) process is crucial. This paper presents the V&V process of the agent-based model (ABM) for resilience analysis of hazard-stricken communities. Tornado hazards, which occur at an ever-increasing rate in the US, were selected as the hazard of interest. Centerville, a virtual community located in the midwestern US, was chosen as the numerical testbed to exemplify the V&V process for the simulation models. A detailed V&V process indicated that the ABM developed for the community resilience analysis is able to characterize the postdisaster recovery process of a community, and therefore, this simulation model provides validated results of resilience assessment. [ABSTRACT FROM AUTHOR]

A home care plan (HCP) can be integrated with an electronic medical records (EMR) system, serving as an example of a real-time system with concurrent processes. To ensure effective operation, HCPs must be free of software bugs. In this paper, we explore the modeling and verification of HCPs from the perspective of scheduling data operationalization. Specifically, we investigate how patients can obtain home services while preventing scheduling conflicts in the context of limited resources. Our goal is to develop and verify robust models for this purpose. We employ formalism to construct and validate the model, following these steps: i) develop requirements and specifications; ii) create a model with concurrent processes using timed automata; and iii) verify the model using UPPAAL tools. Our study focuses on HCP implementation at a regional general hospital in Banyumas District, Central Java, Indonesia. The results include models and specifications based on timed automata and timed computation tree logic (TCTL). We successfully verified a concurrent model that utilizes synchronized counter variables and a sender-receiver approach to analyze collision constraints arising from the synchronization of patient and resource plans. [ABSTRACT FROM AUTHOR]

Within the Discrete Element Method (DEM) framework, the multi-sphere model capable of creating irregular-shaped particles by several sub-spheres attracts increasing attention. Traditionally, the creation of irregular-shaped particles using the multi-sphere model requires manual determination of the position and diameter of each sub-sphere, which extremely increases the difficulty and workload of DEM modeling of irregular-shaped particles. To tackle this issue, a new automatic generation algorithm that helps to create arbitrary-shaped multi-sphere particles automatically was developed in this study. The quality of created multi-sphere particles can be easily controlled by adjusting the number of sub-spheres and size factor referred to as the size ratio of the smallest sub-sphere to the largest sub-sphere. To verify the effectiveness of the newly developed automatic generation algorithm, two verification tests were conducted in this study: (i) The packing behavior of irregular-shaped particles in a rectangular container and (ii) the mechanical behavior of irregular-shaped particles under the uniaxial compression. The fill heights of the simulations were in line with those of the experiments with an error of less than 8%. The mechanical behavior of irregular-shaped particles under the uniaxial compression can also be well reproduced. Besides, the influence of important parameters on simulation accuracy was also investigated. The results demonstrated that the newly developed automatic generation algorithm can accurately create complex-shaped particles with a small number of sub-spheres. Increasing the number of sub-spheres will improve the simulation accuracy but at the expense of computational efficiency. A larger size factor leads to higher computational efficiency in DEM simulation but is accompanied by a significant loss of accuracy. [ABSTRACT FROM AUTHOR]

The adoption of in vivo digital measures in pharmaceutical research and development (R&D) presents an opportunity to enhance the efficiency and effectiveness of discovering and developing new therapeutics. For clinical measures, the Digital Medicine Society's (DiMe) V3 Framework is a comprehensive validation framework that encompasses verification, analytical validation, and clinical validation. This manuscript describes collaborative efforts to adapt this framework to ensure the reliability and relevance of digital measures for a preclinical context. Verification ensures that digital technologies accurately capture and store raw data. Analytical validation assesses the precision and accuracy of algorithms that transform raw data into meaningful biological metrics. Clinical validation confirms that these digital measures accurately reflect the biological or functional states in animal models relevant to their context of use. By widely adopting this structured approach, stakeholders—including researchers, technology developers, and regulators—can enhance the reliability and applicability of digital measures in preclinical research, ultimately supporting more robust and translatable drug discovery and development processes. [ABSTRACT FROM AUTHOR]

Dynamic symmetric searchable encryption (DSSE) allows clients to perform keyword searches and updates on encrypted databases outsourced to cloud servers. Ensuring forward privacy is a crucial security property for DSSE schemes to protect data privacy. However, existing forward-private DSSE schemes face significant limitations: they either rely on an honest-but-curious server, assuming it always returns correct search results without providing verification functionality, or they lack support for fine-grained attribute-based searches and access control. As a result, these schemes cannot be directly applied to attribute-based databases. In this paper, we propose the first verifiable forward-private DSSE scheme suitable for attribute-based databases. Specifically, we construct a secure index based on attribute elements to realize fine-grained searches on attribute-value type databases while ensuring the forward privacy of the scheme. We also design a novel verification tag using symmetric homomorphic encryption to verify the correctness of search results. In addition, our scheme achieves access control functionality to ensure that different users can only access authorized files. Experimental evaluations show that our scheme has advantage in the update, search and verification processes. And the security analysis proves our scheme is secure. [ABSTRACT FROM AUTHOR]

The construction of (hierarchical) curl‐conforming basis functions has been a hot topic in the last decades in the finite element community. Especially, functions applied to simplices have been quite popular after the work by Nédélec in 1980. Many mixed‐order and full‐order families have been provided in the last years, but sometimes, it is difficult to assess if they belong to the original space proposed by Nédélec (especially when orthogonalization procedures are applied). Here, a tool to determine if a family of basis functions belongs to the Nédélec space is provided. Since affine coordinates are the most frequent choice for simplices, particularities about its use with this kind of coordinates are detailed. A detailed survey of existing families is provided, and the practical application of the tool to a representative set of these families is discussed. The tool is also available for the community in a public repository. [ABSTRACT FROM AUTHOR]

ABSTRACT Collision ESD between charged metallic objects below 1000 V causes electromagnetic interference in electronic equipment and devices. This interference is being observed to intensify at lower charging voltages. The phenomenon was first identified by Masmitsu Honda, but its underlying mechanism remains unclear even today. Originally, the charging voltage and spark length of collision ESD are unknown due to measurement difficulties, making it extremely challenging to establish the relationship between the radiated electric field strength and the spark property in such cases. In this study, to clarify the above mentioned electromagnetic phenomenon in collision ESD, a method of calculating the radiated electric field along with a spark length estimated from the measurement strength of radiated field peak is presented using the spark resistance law developed by Rompe and Weizel. The validity is confirmed by our previous measurement data on radiated electric field due to the collision ESD between charged spherical electrodes with a diameter of 30 mm at charging voltages from 300 to 600 V, employing an optical field probe with a wideband up to 10 GHz. The estimated spark length is verified by comparing it with the spark lengths based on an empirical Paschen's formula between fixed electrodes and the discharge data from past literature on metal electrodes, revealing the peculiarity effect of the radiated electric field strength caused by “constant breakdown potential gradient” that occurs at charging voltages below 1000 V. [ABSTRACT FROM AUTHOR]

The results of a pilot study performed on data from selected dwellings in Slovakia suggested that the best agreement between measured and calculated annual mean indoor radon activity concentration (RAC) were obtained by using seasonal correction factors (SCF) determined for winter season. In this paper, SCF was applied on results obtained during a new, independent radon survey conducted in homes during years 2022–2023. In this study, 79 rooms were monitored throughout the year in four cycles based on 3 month indoor radon measurements. The preliminary results show a good agreement between measured and calculated annual mean RAC. [ABSTRACT FROM AUTHOR]

On face recognition, person and vehicle re-identification tasks, different networks and losses have been proposed to learn better features, which further maximizes the decision margin in the feature space. Despite the promising progress having been made, it still remains a challenge to discriminate the different but similar targets while recognizing the same but dissimilar objects, which results from the contradiction between the information retention and the intra-/inter-class distance optimization in the static feature representation methods. The similarity of the static features is insufficient to represent the relationship between diverse images. In this paper, a novel DiffBlock module is proposed to compare the pairwise intermediate features and amplify the difference between the samples. Then SNND (siamese neural network with DiffBlock) is proposed to progressively dig out the discriminative information and judge the relationship between the samples precisely. Extensive experiments on multiple benchmarks for face, person and vehicle verification show that our proposed SNND significantly outperforms previous state-of-the-art methods. [ABSTRACT FROM AUTHOR]

This study focuses on the formal verification of a parallel version of the minimax algorithm using the mCRL2 modeling language, applied to the game of Connect 4. The research aims to ensure that the algorithm behaves correctly in concurrent execution environments by providing a formal model and conducting rigorous verification. The parallel version of minimax distributes computations across multiple threads, with each thread evaluating different successor states concurrently. Using mCRL2, we specify the algorithm's behavior, generate Labeled Transition Systems (LTSs), and verify critical properties such as the absence of deadlocks, liveness, and correctness of state transitions. The formal verification process demonstrates that the proposed model accurately represents the parallel minimax algorithm and ensures its reliability by verifying properties that guarantee unique and non-redundant actions throughout the execution. The findings highlight the value of formal methods in validating the correctness of parallel artificial intelligence algorithms, laying the foundation for future optimizations that focus on performance. [ABSTRACT FROM AUTHOR]

Introduction Military Physical Training programs represent a constant challenge for the Armed Forces to improve body composition indices and physical fitness levels. This study aimed to verify the influence of the type of training on the physical fitness and body composition of army cadets, using 2 strategies: a sports program (Athletes group) and conventional physical training (Traditional group). Materials and Methods This study involved new entrant male cadets who were selected for the Athletes group (n = 243, 19.08 ± 1.23 years) or the Traditional group (n = 356, 18.89 ± 0.97 years), with assessments occurring before and after the period of training (31.4 ± 3.9 weeks). Dual-energy X-ray absorptiometry was used to measure the bone mineral content (BMC), fat mass (FM), percentage of fat mass (%FM), and lean soft tissue (LST). The physical tests evaluated the 3,000 m run (RUN), 50 m swim (SWIM), pull-ups (PULL) on the horizontal bar, push-ups (PUSH) on the ground, and abdominal flexion (SITUP). Results Time × group interaction effects were observed for BMC (P  < .001), LST (P  < .023), RUN (P  < .001), PULL (P  = .006), PUSH (P  < .001), SITUP (P  = .007), and SWIM (P  < .001). A significant effect of time was noted for all variables analyzed in both groups, except %FM. The Athletes group achieved better results in body composition and in PULL, PUSH, RUN, and SWIM at baseline and after the training period. The Traditional group demonstrated higher relative changes (%) after the training period in the LST (P  = .001), PULL (P  < .001), PUSH (P  < .001), SITUP (P  < .004), and SWIM (P  < .001) compared to the Athletes group. Conclusion Both physical training programs improved body composition and physical performance. [ABSTRACT FROM AUTHOR]