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We present the use of interconnected optical mesh networks for early earthquake detection and localization, exploiting the existing terrestrial fiber infrastructure. Employing a waveplate model, we integrate real ground displacement data from seven earthquakes with magnitudes ranging from four to six to simulate the strains within fiber cables and collect a large set of light polarization evolution data. These simulations help to enhance a machine learning model that is trained and validated to detect primary wave arrivals that precede earthquakes' destructive surface waves. The validation results show that the model achieves over 95% accuracy. The machine learning model is then tested against an M4.3 earthquake, exploiting three interconnected mesh networks as a smart sensing grid. Each network is equipped with a sensing fiber placed to correspond with three distinct seismic stations. The objective is to confirm earthquake detection across the interconnected networks, localize the epicenter coordinates via a triangulation method and calculate the fiber-to-epicenter distance. This setup allows early warning generation for municipalities close to the epicenter location, progressing to those further away. The model testing shows a 98% accuracy in detecting primary waves and a one second detection time, affording nearby areas 21 s to take countermeasures, which extends to 57 s in more distant areas.

Conventionally processed precipitation hardening aluminum alloys are generally treated with T6 heat treatments which are time-consuming and generally optimized for conventionally processed microstructures. Alternatively, parts produced by laser powder bed fusion (L-PBF) are characterized by unique microstructures made of very fine and metastable phases. These peculiar features require specifically optimized heat treatments. This work evaluates the effects of a short T6 heat treatment on L-PBF AlSi7Mg samples. The samples underwent a solution step of 15 min at 540 °C followed by water quenching and subsequently by an artificial aging at 170 °C for 2-8 h. The heat treated samples were characterized from a microstructural and mechanical point of view and compared with both as-built and direct aging (DA) treated samples. The results show that a 15 min solution treatment at 540 °C allows the dissolution of the very fine phases obtained during the L-PBF process; the subsequent heat treatment at 170 °C for 6 h makes it possible to obtain slightly lower tensile properties compared to those of the standard T6. With respect to the DA samples, higher elongation was achieved. These results show that this heat treatment can be of great benefit for the industry.

Network operators are aiming to overcome the envisioned data traffic crunch by relying on already installed fiber cables. Multiband optical line systems (LSs) will thus be the solution, starting from the extension to C+L band transmission. Such a bandwidth extension also speeds up network disaggregation to avoid an increase in costs. Thus, LS controllers need quality-of-transmission estimator (QoT-E) modules capable of quickly estimating the merit of lightpaths, and so analytical models for the transmission layer are mandatory. We review the generalized Gaussian noise (GGN) model for wideband prediction of nonlinear interference generation and validate its accuracy by comparing C+L simulative results to model predictions. Results are obtained for the case of amplification using a hybrid Raman and erbium-doped fiber amplifier, and display excellent conservative accuracy. We also present an experimental validation performed on commercial equipment that confirms how the GGN model is the most feasible solution for QoT-E modules in multiband LS controllers, enabling a frequency-resolved minimization of system margins. [ABSTRACT FROM AUTHOR]

The Covid-19 pandemic showed forcefully the fundamental importance broadband data communication and the internet has in our society. Optical communications forms the undisputable backbone of this critical infrastructure, and it is supported by an interdisciplinary research community striving to improve and develop it further. Since the first 'Roadmap of optical communications' was published in 2016, the field has seen significant progress in all areas, and time is ripe for an update of the research status. The optical communications area has become increasingly diverse, covering research in fundamental physics and materials science, high-speed electronics and photonics, signal processing and coding, and communication systems and networks. This roadmap describes state-of-the-art and future outlooks in the optical communications field. The article is divided into 20 sections on selected areas, each written by a leading expert in that area. The sections are thematically grouped into four parts with 4–6 sections each, covering, respectively, hardware, algorithms, networks and systems. Each section describes the current status, the future challenges, and development needed to meet said challenges in their area. As a whole, this roadmap provides a comprehensive and unprecedented overview of the contemporary optical communications research, and should be essential reading for researchers at any level active in this field. [ABSTRACT FROM AUTHOR]

The traditional base station in C-RAN is divided into three parts: a pool of centralized baseband units (BBUs), a fronthaul network that links the BBUs and remote radio units (RRUs), and RRUs. This paper proposes a novel cooperative algorithm for resource optimization in a time-wavelength division multiplexed (TWDM) passive optical network (PON) incorporating a cloud radio access network (C-RAN). First, a joint collaborative strategy is deployed to optimize cooperative caching and transmission in the wireless and optical domains. Then, the quality of experience (QoE) is improved by bandwidth configuration and caching. Simulation results show that the average throughput of the proposed QoE-aware video cooperative caching and transmission mechanism (QACCTM) algorithm is approximately 30% higher than that of other algorithms. Compared with the relative average residual clutter power (RARCP) and quality-aware wireless edge caching (QAWEC) algorithms, the proposed QACCTM algorithm reduces the access delay by approximately 27.1% and 15.9%, respectively. [ABSTRACT FROM AUTHOR]

The capacity of passive optical networks (PONs) is continuously increasing, and it has been standardized up to 50 Gbit/s. The two main standardization organizations, IEEE and ITU-T, are actively working on the next-generation PON, which appears to be a 100G-PON still based on intensity modulation. Even though direct detection would be preferred for its cost and simplicity, the choice of coherent detection seems inevitable when the bit rate reaches 200–400 Gbit/s, specifically to guarantee the optical power budget requirement of an access network. The introduction of coherent systems in the PON scenario, allowing high-power-budget performances, should encouragetelecom operators to merge the metro and access networks into a single domain. This paper analyzes the mentioned metro + PON convergence scenario with experimental results focusing on a 400 Gbit/s fully coherent transmission (50 GBaud PM-16QAM). We characterize three different transceivers, two of which are pre-commercials. We perform experimental demonstrations, with real urban fiber and laboratory set ups, of the metro–access convergence network in terms of the minimum OSNR value of the metro path, producing an acceptable optical power budget within the access network. Our work demonstrates feasibility of merging the metro–access network by using currently coherent optical transceivers for PON applications. [ABSTRACT FROM AUTHOR]

Efficient network management in optical backbone networks is essential to manage continuous traffic growth. To accommodate this growth, network operators need to upgrade their infrastructure at appropriate times. Given the cost constraint of upgrading the entire network at once, upgrading the network periodically in multiple batches is a more pragmatic approach to meet the growing demands. While multi-period, batch-upgrade strategies to increase network capacity from the conventional C band to C+L bands have been proposed, they did not consider so far the possibility to re-provision existing traffic. In this work, we investigate how to selectively re-provision connections from C band to L band during a batch upgrade. This is to ensure greater availability of C-band resources which can help to delay network upgrade and hence reduce upgrade cost, while limiting the number of disrupted connections in the network. This study proposes two re-provisioning strategies, namely, Budget-Based (BB) and Margin-Aware (MA) re-provisioning, which rely on the Quality of Transmission (QoT) of lightpaths. These strategies leverage the knowledge of Generalized Signal-to-Noise Ratio (GSNR) to choose which lightpaths to re-provision. We compare these strategies with a baseline distance-based strategy that uses path length to select and re-provision lightpaths. We also incorporate Machine Learning techniques for QoT estimation of lightpaths to reduce the computational time required for optical-path feasibility check. Numerical results show that, compared to distance-based strategy, BB and MA strategies reduce disruption by about 22% and 27%, respectively, in representative network topologies. [ABSTRACT FROM AUTHOR]

The C+L band elastic optical networks (C+L-EONs) increase the network capacity significantly. However, the introduction of an L band enhances the inter-channel stimulated Raman scattering effect (ISRS), consequently deteriorating the quality of transmission (QoT) of the signal. Furthermore, spectrum allocation leads to spectrum fragmentation inevitably, which escalates the bandwidth blocking rate. In addition, in C+L-EONs, a single fiber carries more services, and once one of the links fails, a huge number of requests will be interrupted, resulting in huge economic losses. Therefore, this paper proposes a survivability routing, band, modulation, and spectrum allocation (RBMSA) algorithm that effectively guarantees service survivability and reduces the impact of ISRS and spectrum fragmentation. The algorithm employs shared backup path protection and a band partitioning method, whereby the spectrum resource of the primary path is assigned in the L band and the backup path is assigned in the C band in order to minimize the impact of ISRS on the QoT of the request while ensuring the survivability of the network. Furthermore, a fragmentation metric accounting for both the free and shared spectrum resource is proposed to mitigate both free and shared spectrum fragmentation. The simulation results reveal that the proposed RBMSA algorithm reduces the bandwidth blocking probability (BBP) and the fragmentation rate (FR) by 47.7% and 21.3%, respectively, and improves the optical signal-to-noise ratio (OSNR) by 4.17 dB in NSFNET. In COST239, the BBP, FR, and OSNR are 22.1%, 21.5%, and 4.71 dB, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Itinerários - Revista de Literatura is the property of Itinerarios - Revista de Literatura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A20X is a high-strength aluminum alloy where TiB2 particles reinforce an Al-Cu-Mg-Ag matrix. In this study, a recently developed composition of Al-Cu-Mg-Ag-TiB2 (A20X) alloy, fabricated by laser powder bed fusion (L-PBF), is investigated under hot isostatically pressed (HIPed) condition. To minimize the L-PBF induced defects (e.g., porosity, lack of fusions), the HIP cycle [ramp at 5/10°C, dwell for 2 h at 103 MPa and uniform rapid cooling (URC®) applied to room temperature] is carried out at 510°C. The stability of the microstructure in crack-free conditions is significantly aided by the HIP cycle. However, as the studied alloy is responsive to precipitation hardening, the HIPed material still needs optimization of its microstructure through carefully designed heat treatments. Micromechanical properties of the materials in all conditions (as-HIPed and two heat treatments) are studied employing depth-sensing nanoindentation testing to assess the variation of location-dependent local mechanical properties of the materials. Microstructural characterization through optical and scanning electron microscopy (SEM) is carried out. The significance of post-processing procedures (such as heat treatments and HIP) and the relationship among processing, post-processing, microstructure and mechanical properties are clarified by this work. [ABSTRACT FROM AUTHOR]

Objectives: In order to test the resistance of rotary instruments to cyclic fatigue fracture and its importance in root canal preparationthe purpose of this study was to see how different tapers (4% and 6%) affected the cyclic fatigue resistance of the Edge File X7 and 2Shape endodontic systems at 45° and 60° canal curvature. Methods: Eighty NiTi files from two different systems (N= 40 each) were used; Group 1: Edge File X7, Group 2: 2Shape. each group was subdivided into four subgroups (N= 10 for each subgroup). The files were evaluated for cyclic fatigue resistance using a modified custom-made static model with 45°and 60° angles having a radius of 3mm and a diameter of 1.5 mm. Each file was rotated in a continuous rotation motion at 300 rpm with 1.2 N.cm torque for TS1, 300 rpm with 2.5 N.cm torque for TS2, and Edge file X7 was used at 300 rpm and 3 N.cm. Until it fractured. The time it took to separate the files was noted. Each file's number of cycles to failure was computed. A Kolmogorov-Smirnova normality test was done for all groups, and a two-way ANOVA was used to statistically examine the data. Results: The ranking of the groups from the highest to the lowest NCF was as follows: EdgeFile 4% 45 degrees (6594.00), EdgeFile 6% 45 degrees (6317.90), EdgeFile 4% 60 degrees (5682.00), EdgeFile 6% 60 degrees (2142.00), 2Shape 4% 45 degrees (2517.00), 2Shape 4% 60 degrees (535.90), 2Shape 6% 45 degrees (474.50), and 2Shape 6% 60 degrees (213.00). Conclusions: Edge File X7 showed better results than the 2Shape system. EdgeFile X7 4% at 45 degrees showed the highest NCF. The 2Shape system 6% at 60 degree that showed lowest NCF. As the canal curvature increased the NCF decreased. Taper 4% is better than taper 6%. [ABSTRACT FROM AUTHOR]

This article examines the linear and non‐linear impacts of innovation on unemployment in 61 countries, covering annual data from 2007 to 2016. The relationship is estimated by deploying the system generalised method of moments (SGMM) estimation. Alternative instruments for the SGMM estimation and cross‐sectional threshold estimation are utilised to investigate the estimation robustness. Although the negative linear relationship between innovation and unemployment is not robustly supported in the linear models, the empirical results of non‐linear models suggest the existence of an inverted‐U effect of innovation on unemployment rate. The marginal impact of innovation also supports the inverted‐U relationship in which only the innovation at the maximum and mean level contributes to lower unemployment. Additionally, the negative marginal effect is larger at the maximum level compared to the mean level. The robustness estimations that use alternative instruments and the Hansen threshold regression also support the non‐linear relationship. On the basis of the findings, although innovation should be encouraged to create more jobs, policymakers are advised to consider interventions in job protection, such as offering reskilling programs to mitigate rising unemployment following the initial efforts to promote innovation. [ABSTRACT FROM AUTHOR]

Metallic powders are widely utilized as feedstock materials in metal additive manufacturing (MAM). However, only a limited number of alloys can currently be processed using these technologies, with most of them being casting alloys. The objective of this study is to investigate novel aluminum alloys produced via a close-coupled gas atomizer (CCGA) by adding an increasing amount of copper (4, 8, and 20 wt%) to an AlSi10Mg alloy. The obtained powders were fully characterized to evaluate the effect of copper, a well-established strengthener for aluminum alloys, in order to correlate the obtained hardness to the powder phase composition and microstructure. In particular, a dendritic microstructure was observed in all alloys, and, as the copper content was increased, the size of the secondary dendrite arm spacing (SDAS) decreased progressively. Consequently, the hardness measured on the powder cross-section linearly increased with the copper content, and the hardness value of 185 ± 13 HV of the AlCu20Si10Mg composition was found to be twice that of the AlSi10Mg alloy (88 ± 5 HV). [ABSTRACT FROM AUTHOR]

Despite the increasing interest in laser powder bed fusion (LPBF), only a few cast aluminum alloys are available for this process. This study focuses on improving the LPBF processability of the A6061 alloy, which is challenging due to its wide solidification range, the dendritic columnar grain growth, and consequent solidification cracking. To address these issues, in situ-synthesized grain refiners can be used to induce equiaxial grain growth and prevent crack formation. A6061 RAM2 powder—a mixture of A6061, Ti, and B4C—was characterized and processed using a low-power LPBF machine to create an in situ particle-reinforced metal matrix composite. Parameter optimization was performed to evaluate the effect of their variation on the printability of the alloy. Microstructural characterization of the samples revealed that the complete reaction and the synthesis of the ceramic reinforcement did not occur. However, TiAl3 was synthesized during the process and promoted a partial grain refinement, leading to the formation of equiaxial grains and preventing the formation of solidification cracks. The tensile tests carried out on the optimized samples exhibit superior mechanical properties compared to those of A6061 processed through LPBF. [ABSTRACT FROM AUTHOR]

Emerging 5G services are changing the way operators manage and optimize their optical metro networks, and the transmission technology and network design process must be tailored to the specific conditions in this segment of the network. Ensuring cost-efficient and energy-efficient network design requires novel approaches that optimize across all network layers. Therefore, to moderate the growth of operators' expenses, in this paper, we investigate low-cost and energy-efficient cross-layer deployment of hierarchical optical transport network (OTN) boards minimizing equipment and energy consumption cost in mixed 10G and 100G/200G filterless metro networks. We propose an integer linear programming (ILP) model and a genetic algorithm (GA) approach that decide: (i) the node structure by deploying various stacked OTN boards (performing traffic-grooming at the electrical layer) and (ii) lightpath establishment considering coherent and non-coherent transmission technologies. Simulative results on real filterless horseshoe networks with real traffic matrices show that our proposed approaches achieve up to 50% cost savings compared to real-world benchmark deployments. [ABSTRACT FROM AUTHOR]

When lightweighting studies are examined, thermoplastic matrix composites come to the fore as they have a high specific strength, are recyclable, and can be formed by thermoforming. Some obscurity needs to be overcome for the rapid forming of three-dimensional parts from laminated thermoplastic composites. In this study, deep drawing experiments were carried out to investigate the forming capabilities of continuous glass fiber reinforced polypropylene composite laminates. The parameters of drawing depth, laminate temperature, holding pressure, and punch speed were examined at each three different levels. The effects of these parameters were evaluated on the earing defect and the thickness distribution. It was concluded that the laminate temperature affected both deformations the most. It was determined that all parameters caused a change in flange diameter, but the amount of earing increased with the increase of drawing depth. It was established that inhomogeneous thickness distributions occurred in the part and the highest thickening took place in the curve region. [ABSTRACT FROM AUTHOR]

The demand for high-performance aluminum components drives research into the design of novel alloys that can be processed by laser-based additive manufacturing. In recent years, the addition of grain refiners proved to be an effective strategy to reduce the hot-cracking of high-strength Al alloys. In this study, the solidification and aging behavior of an Al2139 alloy doped with additions of Zr and Ti for L-PBF was investigated. These elements favored the formation of a fine-grained structure free of cracks. The formation of Al3(Zr,Ti) inoculants was predicted by Scheil simulations and observed as cuboidal particles in the center of α-Al grains. The microstructure of the as-built material featured fine and fully equiaxed grains, which appeared comparatively finer at the edge (300–600 nm) and coarser (0.8–2.0 μm) at the center of the molten pools. In both cases, there was evidence of Cu and Mg micro-segregations at the grain boundaries. The microhardness of 109.7 HV0.5 in the as-built state was increased to 186.1 HV0.5 after optimized T4 heat treatment, responsible for the precipitation of many rod-shaped Zr- and Ti-based second phases and quasi-spherical Cu-, Mn-, and Fe-rich particles. Prolonged exposure carried out to simulate high-temperature service caused a drop in microhardness and marked modification of the microstructure, evidenced by the rearrangement and subsequent spheroidization of Cu- and Mg-rich particles at the grain boundaries. [ABSTRACT FROM AUTHOR]

Ultra-wideband (UWB) wavelength division multiplexing (WDM) transmission, which utilizes low-loss spectral windows of single-mode fiber for data transmission, is a highly promising method for increasing the capacity of optical communication. In this paper, we investigate the performance of a UWB WDM transmission system that covers the widely used C+L band as well as the additional O-, E-, and S-bands. We establish the transmission system for UWB and discuss the effects of the channel, including Kerr nonlinearity and inter-channel interference from inter-channel stimulated Raman scattering (ISRS) between O-, E-, S-, C-, and L-bands. Moreover, we demonstrate an optimization scheme for compensating the spectral power tilt caused by SRS in the S+C+L band system, which utilizes the Raman amplifier and the partition particle swarm optimization (PPSO) algorithm. The results show that the power tilt value of the algorithm is reduced from 18 to 2.93 dB, and the iteration speed is improved by 10% compared with the normal particle swarm algorithm. The scheme provides an efficient way to improve the generalized mutual information (GMI) performance of UWB WDM systems. [ABSTRACT FROM AUTHOR]

Vibration of manufacturing machine parts can be reduced by applying CFRP to precision machines. Recently, the use of 3D printers in manufacturing has increased. However, there are few studies on the vibration characteristics of 3D printed composite materials. The objective of this study is to analyze the vibration reduction effect of a 3D printed composite material used as a CFRP chuck adapter. The existing chuck adapter is made of steel. In this study, the vibration values for three types of CFRP, steel, and CFRP with steel chuck adapters are compared. The products were rotated at 10, 500, and 1000 rpm, and the vibration velocity and displacement were calculated as an average value after repeating each measurement 5 times. Vibration velocity was improved by up to 64% and displacement by up to 31.1%. These results can be usefully applied to other mechanical parts requiring vibration damping. [ABSTRACT FROM AUTHOR]

The enhancement of fuel economy and the emission of greenhouse gases are the key growing challenges around the globe that drive automobile manufacturers to produce lightweight vehicles. Additionally, the reduction in the weight of the vehicle could contribute to its recyclability and performance (for example crashworthiness and impact resistance). One of the strategies is to develop high-performance lightweight materials by the replacement of conventional materials such as steel and cast iron with lightweight materials. The lightweight composite which is commonly referred to as fiber-reinforced plastics (FRP) composite is one of the lightweight materials to achieve fuel efficiency and the reduction of CO2 emission. However, the damage of FRP composite under impact loading is one of the critical factors which affects its structural application. The bumper beam plays a key role in bearing sudden impact during a collision. Polymer composite materials have been abundantly used in a variety of applications such as transportation industries. The main thrust of the present paper deals with the use of high-strength glass fibers as the reinforcing member in the polymer composite to develop a car bumper beam. The mechanical performance and manufacturing techniques are discussed. Based on the literature studies, glass fiber-reinforced composite (GRP) provides more promise in the automotive industry compared to conventional materials such as car bumper beams. [ABSTRACT FROM AUTHOR]

Failure management plays a significant role in optical networks. It ensures secure operation, mitigates potential risks, and executes proactive protection. Machine learning (ML) is considered to be an extremely powerful technique for performing comprehensive data analysis and complex network management and is widely utilized for failure management in optical networks to revolutionize the conventional manual methods. In this study, the background of failure management is introduced, where typical failure tasks, physical objects, ML algorithms, data sources, and extracted information are illustrated in detail. An overview of the applications of ML in failure management is provided in terms of alarm analysis, failure prediction, failure detection, failure localization, and failure identification. Finally, the future directions on ML for failure management are discussed from the perspective of data, model, task, and emerging techniques. [ABSTRACT FROM AUTHOR]

The artificial aging heat treatments performed directly on as-built and solubilized AlSi7Mg0.6 and AlSi10Mg0.3 samples were characterized and discussed. The analysed bars and billets (height of 300 mm) were manufactured via the Laser Powder-Bed Fusion process on a build platform heated at 150 °C. Therefore, its influence on the as-built samples was studied in terms of mechanical performance variations between the bottom and top regions. Vickers microhardness measurements were performed to obtain aging profiles after direct aging (175–225 °C) and T6 heat treatments and to highlight better time and temperature parameters to optimize the mechanical properties of both alloys. SEM observations were used to characterize the microstructure before and after the heat treatments and its influence on the fracture mechanisms. Generally, the direct aging heat treatments show the same effects on both aluminium alloys, unlike the solubilization at 505 °C followed by artificial aging at 175 °C. The strengths vs. elongation values obtained after the direct aging treatments are better than those exhibited by T6 as highlighted by the quality index. [ABSTRACT FROM AUTHOR]

We investigate quality of transmission (QoT) estimation in a multi-band transmission scenario, including a wideband description of the frequency-dependent physical layer parameters and a disaggregated QoT estimation approach.In particular, we use experimentally-derived erbium- and thulium-doped fiber amplifier operational data, and simulate the generation of the nonlinear interference (NLI) noise by comparing implementations of the split-step Fourier method, the generalized Gaussian noise (GGN) model implemented in the open-source GNPy library, and an efficient approximation that provides accurate results in a limited computational time. The latter semi-analytical solution is obtained by approaching the Manakov equation from a disaggregated standpoint, including the power transfer induced by stimulated Raman scattering, along with the frequency-dependent evolution of the fiber parameters of loss, dispersion and the nonlinearity coefficient. We validate the proposed approximation within a C+L+S 400 G transmission scenario and investigate 21 channels under test that are equally spaced along the three bands. [ABSTRACT FROM AUTHOR]

Featured Application: Mass production of CFRP car door panels with NVH embedded system. The increasing use of composite materials in the automotive field requires more attention with regards to the appearance of noise, vibration and harshness (NVH) study in cars construction. However, in car door panels production, impact characteristics need to be evaluated in sandwich laminates. Furthermore, it is important to consider the effect of prolonged environmental aging on crashworthiness properties. The innovative content of the work is the hygrothermal effects evaluation on impact performance for two damped CFRP sandwich laminates. In this paper, two damping materials, Kraibon HHZ9578/99 and SUT9609/24, were used as core between two skins of CFRP for sandwich composite production. Freeze-Thaw aging treatment according to IEC 60068, specific for Automotive, was performed to investigate environmental effects on components. Up to 750 h, it was demonstrated that water absorption is regulated by Fick's Law. The low-velocity impact behavior of the damped sandwiches has been studied according to ASTM D7136 throughout drop dart test equipment. Both main peak forces and energy absorption characteristics are negatively affected by aging condition. The introduction of damping core inside the composite structure of vehicle components can satisfy NVH constrictions. By contrast, at least same operating conditions must be assured in relation to not-damped components. [ABSTRACT FROM AUTHOR]

This period of mandated remote work has been challenging the Romanian employees to adept to the new paradigm of telework for most of them. While prior to COVID-19 pandemic employees were accustom with the work environment and its variables, they were suddenly replaced. The psychological place for restoration, called home, got invaded and occupied by working life. In this time remote workers were learning to adapt to the new way of working from home and balancing it with everyday life. While employers are searching for new and performing approach to accomplish their goals, employees are addressing new conditions affecting their working performance and personal or family life. The study presents and analyses data of two surveys conducted by the "European Foundation for the Improvement of Living and Working Conditions". The impact and consequences of telework on work-life balance and well-being of workers are discussed, seeing that the working time and work intensity dimensions have a direct influence. The search for sustainable telework requires customized working conditions, adapted skills, tackling emerging risks and involving all stakeholders in Romanian working environment. [ABSTRACT FROM AUTHOR]

Unmanned Aerial Vehicle (UAV) with a server which has powerful computing ability can fly over Internet of Thing (IoT) devices and conduct task offloading, giving rise to the so-called UAV-enhanced edge computing network. However, energy efficient and trustworthy UAV-enhanced edge computing is still a challenging issue. In this paper, a UAV-Trust based Task Offloading (UAV-TTO) scheme is proposed to offload tasks in an energy efficient and reliable way for IoT devices. The main innovations are as follows: (1) A Cluster based Task Offloading (CTO) approach is proposed in which tasks only need to route to any IoT devices within a cluster. The disadvantage of long flight distance and large energy consumption for UAV in traditional method can be overcame. Besides, the CTO approach avoids the far routing distance to the cluster head and the excessive data load. (2) A Traceback based Trust Evaluation (TTE) mechanism is proposed to evaluate the trust of devices. In this mechanism, the UAV can collect the task forwarding information provided by IoT devices when flying over the cluster. Then, we conduct a trust evaluation and reasoning mechanism according to the trust evidence collected to obtain more accurate evaluation results. IoT devices with high trustfulness will be selected to participate in task offloading, malicious devices will be excluded, so the efficiency of task offloading can be significantly improved. The UAV trajectory optimization strategy is also proposed to assist task offloading by considering trust and energy consumption. Extensive experimental results demonstrate that the proposed UAV-TTO scheme can reduce the total energy consumption for accomplishing the tasks effectively, evaluate the trust of IoT devices accurately and improve the success rate of task offloading. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Educação e Pesquisa em Contabilidade is the property of Revista de Educacao e Pesquisa em Contabilidade and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article aims to survey the works of philosopher María Zambrano and poet Rina Sara Virgillito, focusing in particular on the image of clearing. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Educação e Pesquisa em Contabilidade is the property of Revista de Educacao e Pesquisa em Contabilidade and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mobile pulse light detection and ranging (LIDAR) is an essential component of autonomous vehicles. The obstacle detection function of autonomous vehicles requires very low failure rates. With an increasing number of autonomous vehicles equipped with LIDAR sensors for use in the detection and avoidance of obstacles and for safe navigation through the environment, the probability of mutual interference becomes an important issue. The reception of foreign laser pulses can lead to problems such as ghost targets or a reduced signal-to-noise ratio (SNR). In this paper, we presented the probability that any LIDAR sensor would interfere mutually by considering spatial and temporal overlaps. We presented some typical mutual interference scenarios in real-world vehicle applications, as well as an analysis of the interference mechanism. We proposed a new multi-plane LIDAR sensor which used coded pulse streams encoded by carrier-hopping prime code (CHPC) technology to measure surrounding perimeters without mutual interference. These encoded pulses utilized a random azimuth identification and checksum with random spreading code. We modeled the entirety of the LIDAR sensor operation in Synopsys OptSim and represented the alien pulse elimination functionality obtained via modeling and simulation. [ABSTRACT FROM AUTHOR]

We proposed a light detection and ranging (LIDAR) system that changes the measurement strategy from a LIDAR system of sequential emission and measuring method to a concurrent firing measuring method. The proposed LIDAR was a 3D scanning LIDAR method that consisted of 128 output channels in one vertical line in the measurement direction and concurrently measured the distance for each of these 128 channels. The scanning LIDAR emitted 128 laser pulse streams encoded by carrier-hopping prime code (CHPC) technology with identification and checksum. When the reflected pulse stream was received and demodulated, the emission channel could be recognized. This information could be used to estimate the time when the laser pulse stream was emitted and calculate the distance to the object reflecting the laser. By using the identification of the received reflected wave, even if several positions were measured at the same time, the measurement position could be recognized after the reception. Extensive simulations indicated that the proposed LIDAR could provide autonomous vehicles or autonomous walking robots with good distance images to recognize the environment ahead. [ABSTRACT FROM AUTHOR]

This research work investigated the influence of the press molding manufacturing process on the mechanical properties, both for thermoplastic and thermosetting fiber reinforced composite materials. The particular geometry of the case study, called Double Dome, was considered in order to verify the behavior of the Thermoplastic and Thermosetting prepreg in terms of shell thickness variation and fibers shear angle evolution during the thermoforming process. The thermoforming simulation was performed using LS-DYNA® Finite Element Analysis (FEA) code, and the results were transferred by Envyo®, a dedicated mapping tool, into a LS-DYNA® virtual model for the structural simulation. A series of Double Dome specimens was produced with industrial equipment, and a bending experimental test was been carried on. Finally, a numerical-experimental correlation was performed, highlighting a significant forecast of the mechanical properties for the considered component. [ABSTRACT FROM AUTHOR]