Advances in Multi-Scale Mechanical Characterization of Materials with Optical Methods

The mechanical characterization of materials embraces many different aspects, such as, for example, (i) to assess materials’ constitutive behavior under static and dynamic conditions; (ii) to analyze material microstructure; (iii) to assess the level of damage developed in the material; (iv) to determine surface/interfacial properties; and (v) to optimize manufacturing processes in terms of process speed and reliability and obtain the highest quality of manufactured products [...]

Evaluation and resolution of many challenges of neural spike-sorting: a new sorter

We evaluate existing spike sorters and present a new one that resolves many sorting challenges. The new sorter, called "full binary pursuit" or FBP, comprises multiple steps. First, it thresholds and clusters to identify the waveforms of all unique neurons in the recording. Second, it uses greedy binary pursuit to optimally assign all the spike events in the original voltages to separable neurons. Third, it resolves spike events that are described more accurately as the superposition of spikes from two other neurons. Fourth, it resolves situations where the recorded neurons drift in amplitude or across electrode contacts during a long recording session. Comparison with other sorters on ground-truth datasets reveals many of the failure modes of spike sorting. We examine overall spike sorter performance in ground-truth datasets and suggest post-sorting analyses that can improve the veracity of neural analyses by minimizing the intrusion of failure modes into analysis and interpretation of neural data. Our analysis reveals the tradeoff between the number of channels a sorter can process, speed of sorting, and some of the failure modes of spike sorting. FBP works best on data from 32 channels or fewer. It trades speed and number of channels for avoidance of specific failure modes that would be challenges for some use cases. We conclude that all spike sorting algorithms studied have advantages and shortcomings, and the appropriate use of a spike sorter requires a detailed assessment of the data being sorted and the experimental goals for analyses.

Performance efficiency of virtual laboratory based on Unity 3D and Blender during the Covid-19 pandemic

Testing the performance efficiency aspect was carried out to test the performance efficiency of the Unity 3D and Blender-based virtual laboratory media during the COVID-19 pandemic at the Electrical Engineering Vocational Laboratory. This test is carried out to test the performance of the media that has been created. The aspects tested are access speed, process speed, and simulation speed when run. Tests were conducted to measure processor and memory consumption through real time monitoring using MSI Afterburner. Divided into 2 stages of testing, namely time behavior and resource utilization. Time-behavior is focused on how long it takes the media or software to provide a response time to perform an action from a certain function. Resource-utilization is the degree to which software uses some resources when doing something under certain conditions.

Numerical Analysis of the Partial Penetration High Power Laser Beam Welding of Thick Sheets at High Process Speeds

The present work is devoted to the numerical analysis of the high-power laser beam welding of thick sheets at different welding speeds. A three-dimensional transient multi-physics numerical model is developed, allowing for the prediction of the keyhole geometry and the final penetration depth. Two ray tracing algorithms are implemented and compared, namely a standard ray tracing approach and an approach using a virtual mesh refinement for a more accurate calculation of the reflection point. Both algorithms are found to provide sufficient accuracy for the prediction of the keyhole depth during laser beam welding with process speeds of up to 1.5mmin−1. However, with the standard algorithm, the penetration depth is underestimated by the model for a process speed of 2.5mmin−1 due to a trapping effect of the laser energy in the top region. In contrast, the virtually refined ray tracing approach results in high accuracy results for process speeds of both 1.5mmin−1 and 2.5mmin−1. A detailed study on the trapping effect is provided, accompanied by a benchmark including a predefined keyhole geometry with typical characteristics for the high-power laser beam welding of thick plates at high process speed, such as deep keyhole, inclined front keyhole wall, and a hump.

Manufacturing PLA/PCL Blends by Ultrasonic Molding Technology

Ultrasonic molding (USM) is a good candidate for studying the plasticization of polymer mixtures or other composite materials due to either the little amount of material needed for processing, low waste or the needed low pressure and residence time of the mold. Thus, the novelty of this research is the capability of USM technology to process PLA/PCL blends and their corresponding neat materials, encompassing all the production stages, from raw material to the final specimen. The major findings of the work revealed that the thermal properties of the blends were not affected by the USM process, although the crystallinity degree experienced variations, decreasing for PLA and increasing for PCL, which was attributed to the crystallization rate of each polymer, the high process speed, the short cooling time and the small particle size. The employed ultrasonic energy increased the molecular weight with low variations through the specimen. However, the degradation results aligned with the expected trend of these material blends. Moreover, this study also showed the effect pellet shape and dimensions have over the process parameters, as well as the effect of the blend composition. It can be concluded that USM is a technology suitable to successfully process PLA/PCL blends with the correct determination of process parameter windows.

O PRINCÍPIO CONSTITUCIONAL DA RAZOÁVEL DURAÇÃO DO PROCESSO E A IMPLEMENTAÇÃO DO PROCESSO JUDICIAL ELETRÔNICO COMO FORMA DE GARANTIR CELERIDADE AOS LITÍGIOS

RESUMOObjetivou-se com este trabalho tratar da informatização dos processos judiciais e da sua relação com a garantia constitucional da razoável duração do processo judicial. O problema da pesquisa cinge na implementação do processo eletrônico como forma de garantir a razoável duração do processo e suas consequências. O objetivo geral é demonstrar que simplesmente digitalizar e transferir os litígios judiciais para o meio eletrônico não é, necessariamente, capaz de garantir a razoável duração do processo. Em muitos casos, a falta de treinamento e de tecnologias para os membros da justiça podem acarretar maior morosidade do judiciário. Optou-se pela análise bibliográfica e jurisprudencial com suporte no método dedutivo. Como resultado observou-se que não basta transferir os autos físicos para o meio eletrônico. Restou comprovada a necessidade de investir em tecnologias e em treinamento da comunidade jurídica como um todo, para garantir ao jurisdicionado um resultado efetivo em tempo razoável.PALAVRAS-CHAVE: Processo; Celeridade; Garantia constitucional; Informatização.ABSTRACTThe objective of this work was to deal with the computerization of judicial proceedings and their relationship with the constitutional guarantee of the reasonable length of the proceedings. The research problem concerns the implementation of the electronic process as a way to guarantee the reasonable duration of the process and its consequences. The overall objective is to demonstrate that simply digitizing and transferring legal disputes to electronic media is not necessarily able to guarantee the reasonable duration of the process. In many cases, the lack of training and technologies for members of the justice system can lead to greater delays in the judiciary. We opted for bibliographic and jurisprudential analysis based on the deductive method. As a result, it was observed that it is not enough to transfer the physical records to the electronic medium. There remains a proven need to invest in technology and training for the legal community as a whole, in order to guarantee the jurisdiction an effective result within a reasonable time.KEYWORDS: Process; Speed; Warranty; Constitutional; Computerization.

Fluctuations of Tracks and Layers during Aluminium Laser Powder-Bed Fusion

Laser Powder-Bed Fusion (LPBF) is one method in Additive Manufacturing where layer-wise complex structures can be built. However, although the LPBF machines produce promising parts, the efficiency and process speed are typically still low, which can make the process expensive and uneconomical. Recent research showed that volume elements in the parts can be melted several times, while only a small material volume is added, which indicates a high loss of energy. In order to understand the process better, in this work, theoretical modeling and smart powder-bed experiments were designed to explain the impact on the track dimensions based on the previously built tracks and layers. It was found that the powder availability varies for each track and has an alternating character within and between layers. The comparison of the simulation and experimental results indicates that the powder pick-up from neighboring powder volumes is the main reason for the variations of the powder availability.

Boosting Stemmer Performance Using Cache Method

Stemming is the process of returning the word to the base word by disappearing the append. This is important to support better information re-meeting. Some research in stemming algorithms includes nazief &adriani algorithms, confix stripping, enhanced confix stripping, arifin and porter algorithms. The stemming algorithm for Bahasa Indonesia is divided into two, namely those that use a dictionary and do not use a dictionary. Some studies have shown that stemmers that use dictionary have high accuracy but low process speed, while stemmers that do not use dictionary have low accuracy but higher process speed. In this study, two methods were used: the stemmer method using cache and stemmer without cache to see the comparison of process speed from stemmers that use dictionary. The test data for this study is text data obtained from the corpus site. Process analysis is completed by calculating each speed, memory usage and cpu of each method, then each method is compared. Results from tests from test data showed that the cache method improved stemmer performance.

Derivation of Appropriate Conditions for Additive Manufacturing Technology Using Hot-Wire Laser Method

The aim of this research was to develop a high-efficiency and high-material-use additive manufacturing technology using the hot-wire laser method. In this study, the optimization of process conditions using a combination of a high-power diode laser with a relatively large rectangular laser spot and a hot-wire system was investigated. The effects of process parameters such as laser power, process speed, and wire feeding rate (wire feeding speed/process speed) on a bead appearance and cross-sectional characteristics (e.g., effective width, effective height, maximum height, and near net shape rate) were studied in detail. The process phenomena during the multi-layer deposition were investigated by in situ observation via a high-speed camera.