Industry 4.0: Mining Physical Defects in Production of Surface-Mount Devices

With the advent of Industry 4.0, production processes have been endowed with intelligent cyber-physical systems generating massive amounts of streaming sensor data. Internet of Things technologies have enabled capturing, managing, and processing production data at a large scale in order to utilize this data as an asset for the optimization of production processes. In this work, we focus on the automatic detection of physical defects in the production of surfacemount devices. We show how to build a classification model based on random forests that efficiently detects defect products with a high degree of precision. In fact, the results of our preliminary experimental analysis indicate that our approach is able to correctly determine defects in a simulated production environment of surface-mount devices with a MCC score of 0.96. We investigate the feasibility of utilizing this approach in realistic settings. We believe that our approach will help to advance the production of surface-mount devices

Validation of the CoGEF Method as a Predictive Tool for Polymer Mechanochemistry

The development of force-responsive molecules called mechanophores is a central component of the field of polymer mechanochemistry. Mechanophores enable the design and fabrication of polymers for a variety of applications ranging from sensing to molecular release and self-healing materials. Nevertheless, an insufficient understanding of structure–activity relationships limits experimental development, and thus computation is necessary to guide the structural design of mechanophores. The constrained geometries simulate external force (CoGEF) method is a highly accessible and straightforward computational technique that simulates the effect of mechanical force on a molecule and enables the prediction of mechanochemical reactivity. Here, we use the CoGEF method to systematically evaluate every covalent mechanophore reported to date and compare the predicted mechanochemical reactivity to experimental results. Molecules that are mechanochemically inactive are also studied as negative controls. In general, mechanochemical reactions predicted with the CoGEF method at the common B3LYP/6-31G* level of density functional theory are in excellent agreement with reactivity determined experimentally. Moreover, bond rupture forces obtained from CoGEF calculations are compared to experimentally measured forces and demonstrated to be reliable indicators of mechanochemical activity. This investigation validates the CoGEF method as a powerful tool for predicting mechanochemical reactivity, enabling its widespread adoption to support the developing field of polymer mechanochemistry. Secondarily, this study provides a contemporary catalog of over 100 mechanophores developed to date

Validation of the CoGEF Method as a Predictive Tool for Polymer Mechanochemistry

The development of force-responsive molecules called mechanophores is a central component of the field of polymer mechanochemistry. Mechanophores enable the design and fabrication of polymers for a variety of applications ranging from sensing to molecular release and self-healing materials. Nevertheless, an insufficient understanding of structure–activity relationships limits experimental development, and thus computation is necessary to guide the structural design of mechanophores. The constrained geometries simulate external force (CoGEF) method is a highly accessible and straightforward computational technique that simulates the effect of mechanical force on a molecule and enables the prediction of mechanochemical reactivity. Here, we use the CoGEF method to systematically evaluate every covalent mechanophore reported to date and compare the predicted mechanochemical reactivity to experimental results. Molecules that are mechanochemically inactive are also studied as negative controls. In general, mechanochemical reactions predicted with the CoGEF method at the common B3LYP/6-31G* level of density functional theory are in excellent agreement with reactivity determined experimentally. Moreover, bond rupture forces obtained from CoGEF calculations are compared to experimentally measured forces and demonstrated to be reliable indicators of mechanochemical activity. This investigation validates the CoGEF method as a powerful tool for predicting mechanochemical reactivity, enabling its widespread adoption to support the developing field of polymer mechanochemistry. Secondarily, this study provides a contemporary catalog of over 100 mechanophores developed to date

Phasic, nonsynaptic GABA-A receptor-mediated inhibition entrains thalamocortical oscillations.

GABA-A receptors (GABA-ARs) are typically expressed at synaptic or nonsynaptic sites mediating phasic and tonic inhibition, respectively. These two forms of inhibition conjointly control various network oscillations. To disentangle their roles in thalamocortical rhythms, we focally deleted synaptic, γ2 subunit-containing GABA-ARs in the thalamus using viral intervention in mice. After successful removal of γ2 subunit clusters, spontaneous and evoked GABAergic synaptic currents disappeared in thalamocortical cells when the presynaptic, reticular thalamic (nRT) neurons fired in tonic mode. However, when nRT cells fired in burst mode, slow phasic GABA-AR-mediated events persisted, indicating a dynamic, burst-specific recruitment of nonsynaptic GABA-ARs. In vivo, removal of synaptic GABA-ARs reduced the firing of individual thalamocortical cells but did not abolish slow oscillations or sleep spindles. We conclude that nonsynaptic GABA-ARs are recruited in a phasic manner specifically during burst firing of nRT cells and provide sufficient GABA-AR activation to control major thalamocortical oscillations

Climatic fluctuations inferred for the Middle and Late Pleniglacial (MIS 2) based on high-resolution (∼ca. 20 y) preliminary environmental magnetic investigation of the loess section of the Madaras brickyard (Hungary)

Abstract The Madaras brickyard section found at the northernmost fringe of the Backa loess plateau is one of the thickest and best-developed last glacial loess sequences of Central Europe. In the present work high-resolution magnetic susceptibility measurements (at 2 cm) were implemented on samples from the 10 m-section corresponding to a period between 29 and 11 KY cal b2K. One aim was to compare the findings with the ice core records of northern Greenland in order to establish a high-resolution paleoclimatic record for the last climatic cycle and with findings documented in other biotic and abiotic proxies so far. Our results revealed a strong variability of loess/paleosol formation during MIS 2. Millennial time-scale climatic events that characterize the North Atlantic during the last climatic cycle have been identified. From 29 ka up to the start of the LGM, the recorded MS values show a weak, negative correlation with the temperature proxy, and a weak positive correlation with the dust concentration of Greenland. A strong correlation was observed with the local paleotemperatures. Local climatic factors must have had a more prominent effect here on loess/paleosol development than the climate shifts over Greenland. During the LGM the same pattern is seen with a stronger correlation with the dust concentrations and a weaker correlation with the local temperature. Local climatic factors, plus dust accumulation, must have had a prominent influence on loess/paleosol development here. From the terminal part of the LGM a strong positive correlation of the MS values with the temperature proxy for Greenland accompanied by a strong negative correlation with the dust concentration values is observed. Correlation with local paleotemperatures is positive and moderate, strong. Here climate shifts over Greenland, as well as local endowments equally had an important role on the development of the MS signal

Atomic Force Microscopy of height fluctuations of fibroblast cells

We investigated the nanometer scale height fluctuations of 3T3 fibroblast cells with the atomic force microscope (AFM) under physiological conditions. Correlation between these fluctuations and lateral cellular motility can be observed. Fluctuations measured on leading edges appear to be predominantly related to actin polymerization-depolymerization processes. We found fast (5 Hz) pulsatory behavior with 1--2 nm amplitude on a cell with low motility showing emphasized structure of stress fibres. Myosin driven contractions of stress fibres are thought to induce this pulsation.Comment: 6 pages, 5 figures, 1 tabl