Protein inspired chemically orthogonal imines for linchpin directed precise and modular labeling of lysine in proteins

The chemical technologies for the precision engineering of proteins connect chemistry, biology, and medicine. However, they face enormous hurdles due to a large pool of competing proteinogenic residues. While resolving...

GEODYNAMICS

The paper analyzes the vertical displacements of the GNSS sites of civil engineering structures caused by non-tidal atmospheric loading (NTAL). The object of the study is the Dnister Hydroelectric Power Plant №1 (HPP-1) and its GNSS monitoring network. The initial data are the RINEX-files of 14 GNSS stations of the Dnister HPP-1 and 8 permanent GNSS stations within a radius of 100 km, the NTAL model downloaded from the repository of German Research Centre for Geosciences GFZ for 2019-2021, and materials on the geological structure of the object. Methods include comparison and analysis of the altitude component of GNSS time series with model values of NTAL as well as interpretation of the geodynamic vertical displacements, taking into account the analysis of the geological structure. As a result, it was found that the sites of the GNSS network of the Dnister HPP-1 undergo less vertical displacements than the permanent GNSS stations within a radius of 100 km. This corresponds to the difference in thickness and density of the rocks under the GNSS sites and stations, so they undergo different elastic deformations by the same NTAL. In addition, the research detected different dynamics of vertical displacements of GNSS sites on the dam and on the river banks. It leads to cracks and deformations of concrete structures in the dam-bank contact zones. During the anomalous impact of NTAL, the altitude of even nearby sites can change if the geological structure beneath them is different. The work shows that for civil engineering structures it is necessary to apply special models to take into account NTAL deformations for high-precision engineering and geodetic measurements.

Femtosecond Laser Precision Engineering: From Micron, Submicron, to Nanoscale

As a noncontact strategy with flexible tools and high efficiency, laser precision engineering is a significant advanced processing way for high-quality micro-/nanostructure fabrication, especially to achieve novel functional photoelectric structures and devices. For the microscale creation, several femtosecond laser fabrication methods, including multiphoton absorption, laser-induced plasma-assisted ablation, and incubation effect have been developed. Meanwhile, the femtosecond laser can be combined with microlens arrays and interference lithography techniques to achieve the structures in submicron scales. Down to nanoscale feature sizes, advanced processing strategies, such as near-field scanning optical microscope, atomic force microscope, and microsphere, are applied in femtosecond laser processing and the minimum nanostructure creation has been pushed down to ~25 nm due to near-field effect. The most fascinating femtosecond laser precision engineering is the possibility of large-area, high-throughput, and far-field nanofabrication. In combination with special strategies, including dual femtosecond laser beam irradiation, ~15 nm nanostructuring can be achieved directly on silicon surfaces in far field and in ambient air. The challenges and perspectives in the femtosecond laser precision engineering are also discussed.

Recent Advances of Artificial Intelligence in Manufacturing Industrial Sectors: A Review

The recent advances in artificial intelligence have already begun to penetrate our daily lives. Even though the development is still in its infancy, it has been shown that it can outperform human beings even in terms of intelligence (e.g., AlphaGo by DeepMind), implying a massive potential for its broader application in various industrial sectors. In particular, the growing public interest in industry 4.0, which focuses on revolutionizing the traditional manufacturing scene, has stimulated a deeper investigation of its possible applications in the related industries. Since it has several limitations that hinder its direct usage, research on the convergence of artificial intelligence with other engineering fields, including precision engineering and manufacturing, is ongoing. This overview looks to summarize some of the important achievements made using artificial intelligence in some of the most influential and lucrative manufacturing industries in hopes of transforming the manufacturing sites.

Combined optimization of a linear PM actuator with trapezoidal PMs and coils considering fringing effect for precision engineering

For precision engineering, a linear PM-moving actuator with trapezoidal PMs and trapezoidal coils considering the fringing effect is proposed. To take into account the effect of the finite-long trapezoidal PM array, an improved Fourier series expansion is developed to calculate the fringing-included magnetic field. Then the full-stroke thrust excited by the trapezoidal coils is accurately predicted and validated by the finite element method. Sensitivity of the trapezoidal parameters of PMs and coils is analyzed, and combined optimization is implemented by the genetic algorithm. Through the Pareto optimal solutions of thrust, the relation of the PM-coil parameter combination is described and formulated by curve fitting. Compared with the traditional rectangular PM actuators or other trapezoidal-typed actuators, the proposed actuator with trapezoidal PMs and coils further decreases the thrust ripple and largely increases the thrust magnitude simultaneously, and reaches an utmost-close effective stroke as well.

Design, Fabrication and Implementation of a High-Performance Compliant Nanopositioner via 3D Printing with Continuous Fiber-Reinforced Composite

Nanopositioning systems have been widely applied in scientific and emerging industrial applications. With simplicity in design and operation, flexure bearings with spatial constraints and voice coil based nano-actuators are considered in designing compliant compact nanopositioning systems. To achieve nano-metric positioning quality, monolithic fabrication of the positioner is preferred, which calls for 3D printing fabrication. However, conventional plastic material-based 3D printing suffers from low mechanical performances, and it is challenging to monolithically fabricate 3D compliant mechanisms with high mechanical performances. Here, we study the fabrication of continuous carbon fiber reinforced composites by 3D printing of the double parallelogram flexure beam structures for spatial constrained nanopositioner with enhanced vertical stiffness. Also, with the consideration of the beam structure design, the process parameters for embedding the carbon fibers are optimized to enhance the beam strengths. Experimental results demonstrate a significant performance improvement with the composite based nanopositioner in both stiffness and natural frequency, and its positioning resolution of 30 nm is achieved. The result of this study will serve as the building block to apply advanced 3D printing of composite structure for precision engineering in the presence of more complex spatial structures.

Precision engineering for ultra-cold atoms and space experiments

Οι υπερ-ψυχρές τεχνολογίες ατόμων υπόσχονται σημαντικές βελτιώσεις στους τομείς της ανίχνευσης, της επικοινωνίας, της κβαντικής προσομοίωσης και του υπολογισμού. Για να αξιοποιηθούν πλήρως οι δυνατότητές τους, πρέπει να αναπτυχθούν πολλές νέες τεχνολογίες. Σε αυτή τη διατριβή επικεντρώνομαι σε τρεις από αυτές: την μηχανική ακρίβειας των κυματοδηγών, την μηχανική ακριβείας της κατάστασης εισόδου του αισθητήρα και τις εξαιρετικά σταθερές και στιβαρές τεχνολογίες για διαστημικές αποστολές. Αυτές οι τρεις κύριες προκλήσεις του πεδίου διερευνώνται σε αυτήν την εργασία. Αρχικά, διερευνώ τα όρια της χωρίς διέγερση μεταφοράς συμπυκνωμάτων Bose-Einstein (BECs) και υπερ-ψυχρών ατομικών νεφών σε κυματοδηγούς μαγνητικού πεδίου (TAAP) με σχήμα δακτυλίου εισάγοντας τεχνητά εμπόδια. Παρατηρείται μια ευρεία περιοχή όπου δεν υπάρχει διέγερση μέχρι την τιμή ενός κατωφλίου, όπου παρατηρείται απότομη αύξηση της διέγερσης του ατομικού νέφους. Παρουσιάζω επίσης μια ακριβή και απλή μέθοδο ανίχνευσης, με μόνο σφάλμα 1% στη μέτρηση του αριθμού των ατόμων. Αυτό αποτελεί βελτίωση περίπου 10 φορές στην ακρίβεια της πειραματικής μας ακολουθίας. Η μέθοδος έχει τη δυνατότητα να εφαρμοστεί ως ελάχιστα καταστρεπτική τεχνική μέτρησης για την κβαντική κατάσταση και τη θερμοκρασία του υπερ-ψυχρού νέφους. Τέλος, αναπτύχθηκε μια συμβατή με το διάστημα σύζευξη οπτικών ινών. Επιτεύχθηκε υψηλή απόδοση σύζευξης της τάξης του 94% και διακυμάνσεις μικρότερες από 1% παρουσία διακυμάνσεων στην θερμοκρασία και κραδασμών. Αυτές οι επιδείξεις ανοίγουν το δρόμο προς την πραγματοποίηση πρακτικών συσκευών που βασίζονται σε υπέρψυχρα νέφη. Στα πλαίσια της εργασίας σχεδιάστηκαν και δημιουργήθηκαν προσαρμοσμένες ηλεκτρονικές διατάξεις και λογισμικό.