Tool flank wear prediction using high-frequency machine data from industrial edge device

Tool flank wear monitoring can minimize machining downtime costs while increasing productivity and product quality. In some industrial applications, only a limited level of tool wear is allowed to attain necessary tolerances. It may become challenging to monitor a limited level of tool wear in the data collected from the machine due to the other components, such as the flexible vibrations of the machine, dominating the measurement signals. In this study, a tool wear monitoring technique to predict limited levels of tool wear from the spindle motor current and dynamometer measurements is presented. High-frequency spindle motor current data is collected with an industrial edge device while the cutting forces and torque are measured with a rotary dynamometer in drilling tests for a selected number of holes. Feature engineering is conducted to identify the statistical features of the measurement signals that are most sensitive to small changes in tool wear. A neural network based on the long short-term memory (LSTM) architecture is developed to predict tool flank wear from the measured spindle motor current and dynamometer signals. It is demonstrated that the proposed technique predicts tool flank wear with good accuracy and high computational efficiency. The proposed technique can easily be implemented in an industrial edge device as a real-time predictive maintenance application to minimize the costs due to manufacturing downtime and tool underuse or overuse.Comment: The first four authors have equal contributio

Functional Diversity and Structural Disorder in the Human Ubiquitination Pathway

The ubiquitin-proteasome system plays a central role in cellular regulation and protein quality control (PQC). The system is built as a pyramid of increasing complexity, with two E1 (ubiquitin activating), few dozen E2 (ubiquitin conjugating) and several hundred E3 (ubiquitin ligase) enzymes. By collecting and analyzing E3 sequences from the KEGG BRITE database and literature, we assembled a coherent dataset of 563 human E3s and analyzed their various physical features. We found an increase in structural disorder of the system with multiple disorder predictors (IUPred - E1: 5.97%, E2: 17.74%, E3: 20.03%). E3s that can bind E2 and substrate simultaneously (single subunit E3, ssE3) have significantly higher disorder (22.98%) than E3s in which E2 binding (multi RING-finger, mRF, 0.62%), scaffolding (6.01%) and substrate binding (adaptor/substrate recognition subunits, 17.33%) functions are separated. In ssE3s, the disorder was localized in the substrate/adaptor binding domains, whereas the E2-binding RING/HECT-domains were structured. To demonstrate the involvement of disorder in E3 function, we applied normal modes and molecular dynamics analyses to show how a disordered and highly flexible linker in human CBL (an E3 that acts as a regulator of several tyrosine kinase-mediated signalling pathways) facilitates long-range conformational changes bringing substrate and E2-binding domains towards each other and thus assisting in ubiquitin transfer. E3s with multiple interaction partners (as evidenced by data in STRING) also possess elevated levels of disorder (hubs, 22.90% vs. non-hubs, 18.36%). Furthermore, a search in PDB uncovered 21 distinct human E3 interactions, in 7 of which the disordered region of E3s undergoes induced folding (or mutual induced folding) in the presence of the partner. In conclusion, our data highlights the primary role of structural disorder in the functions of E3 ligases that manifests itself in the substrate/adaptor binding functions as well as the mechanism of ubiquitin transfer by long-range conformational transitions. © 2013 Bhowmick et al

Long term results of free flaps in facial contour restoration

Facial defects can be reconstructed by utilization of free tissue transfers. This can be the result of a congenital, post-traumatic, post-radiotherapy or post-surgical condition. Microsurgical reconstruction techniques enable one stage correction. We have utilized various free flaps (omentum 4, serratus anterior muscle Rap 3, scapular flap 4 and groin flap 1) for facial contour restoration in 12 patients who had tissue deficits because of Romberg's disease, hemifacial microsomia, hypoplasia due to radiotherapy, tumor resection and post trauma. All vessel anastomosis were performed by the second author. No flap was lost. In conclusion, late descent of omentum, muscle and dermal fat tissue could not be prevented, whereas there was relatively minimal sagging of scapular tissue, therefore multiple flap revisions were performed in all patients in the long term

False aneurysm of the princeps pollicis artery of the hand

Aneurysms of the arteries of the wrist and hand are uncommon, and traumatic aneurysm of the princeps pollicis artery is extremely rare. In this paper, a 24-year-old man who had a traumatic aneurysm of the princeps pollicis artery in his right wrist is presented

Histologic analysis of prefabricated, vascularized bone grafts: An experimental study in rabbits

Purpose: The purpose of this study was to investigate the cellular quality of prefabricated bone grafts