scholarly journals Mining Periodic Patterns from Nested Event Logs

2014 ◽  
Author(s):  
Janusz R. Getta ◽  
Marcin Zimniak ◽  
Wolfgang Benn
Keyword(s):  
Periodic Patterns ◽  
Event Logs

Forced Periodic and Quasi-Periodic Patterns in Anisotropic Systems

1996 ◽  
Vol 6 (2) ◽  
pp. 305-328 ◽  
Author(s):  
Atsushi Ogawa ◽  
Walter Zimmermann ◽  
Kyozi Kawasaki ◽  
Toshihiro Kawakatsu
Keyword(s):  
Periodic Patterns ◽  
Anisotropic Systems

High-Frequency Periodic Patterns Driven by Non-Radiative Fields Coupled with Marangoni Convection Instabilities on Laser-Excited Surfaces

2019 ◽  
Author(s):  
Anton Rudenko ◽  
Anthony Abou-Saleh ◽  
Florent Pigeon ◽  
Cyril Mauclair ◽  
Florence Garrelie, Prof. ◽  
...  
Keyword(s):  
High Frequency ◽  
Marangoni Convection ◽  
Periodic Patterns

scholarly journals Short-Pulse Lasers: A Versatile Tool in Creating Novel Nano-/Micro-Structures and Compositional Analysis for Healthcare and Wellbeing Challenges

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 712
Author(s):  
Ahmed Al-Kattan ◽  
David Grojo ◽  
Christophe Drouet ◽  
Alexandros Mouskeftaras ◽  
Philippe Delaporte ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Surface Engineering ◽  
Short Pulse ◽  
Chemical Properties ◽  
Compositional Analysis ◽  
Periodic Patterns ◽  
Laser Ablation In Liquid ◽  
Micro Scale ◽  
Direct Laser ◽  
Contact Free

Driven by flexibility, precision, repeatability and eco-friendliness, laser-based technologies have attracted great interest to engineer or to analyze materials in various fields including energy, environment, biology and medicine. A major advantage of laser processing relies on the ability to directly structure matter at different scales and to prepare novel materials with unique physical and chemical properties. It is also a contact-free approach that makes it possible to work in inert or reactive liquid or gaseous environment. This leads today to a unique opportunity for designing, fabricating and even analyzing novel complex bio-systems. To illustrate this potential, in this paper, we gather our recent research on four types of laser-based methods relevant for nano-/micro-scale applications. First, we present and discuss pulsed laser ablation in liquid, exploited today for synthetizing ultraclean “bare” nanoparticles attractive for medicine and tissue engineering applications. Second, we discuss robust methods for rapid surface and bulk machining (subtractive manufacturing) at different scales by laser ablation. Among them, the microsphere-assisted laser surface engineering is detailed for its appropriateness to design structured substrates with hierarchically periodic patterns at nano-/micro-scale without chemical treatments. Third, we address the laser-induced forward transfer, a technology based on direct laser printing, to transfer and assemble a multitude of materials (additive structuring), including biological moiety without alteration of functionality. Finally, the fourth method is about chemical analysis: we present the potential of laser-induced breakdown spectroscopy, providing a unique tool for contact-free and space-resolved elemental analysis of organic materials. Overall, we present and discuss the prospect and complementarity of emerging reliable laser technologies, to address challenges in materials’ preparation relevant for the development of innovative multi-scale and multi-material platforms for bio-applications.

scholarly journals Towards a Domain-Specific Modeling Language for Extracting Event Logs from ERP Systems

2021 ◽  
Vol 11 (12) ◽  
pp. 5476
Author(s):  
Ana Pajić Simović ◽  
Slađan Babarogić ◽  
Ognjen Pantelić ◽  
Stefan Krstović
Keyword(s):  
Process Mining ◽  
Modeling Language ◽  
Sufficient Information ◽  
Event Data ◽  
Erp Systems ◽  
Domain Experts ◽  
Domain Specific ◽  
Event Logs ◽  
Domain Specific Modeling ◽  
Specific Modeling

Enterprise resource planning (ERP) systems are often seen as viable sources of data for process mining analysis. To perform most of the existing process mining techniques, it is necessary to obtain a valid event log that is fully compliant with the eXtensible Event Stream (XES) standard. In ERP systems, such event logs are not available as the concept of business activity is missing. Extracting event data from an ERP database is not a trivial task and requires in-depth knowledge of the business processes and underlying data structure. Therefore, domain experts require proper techniques and tools for extracting event data from ERP databases. In this paper, we present the full specification of a domain-specific modeling language for facilitating the extraction of appropriate event data from transactional databases by domain experts. The modeling language has been developed to support complex ambiguous cases when using ERP systems. We demonstrate its applicability using a case study with real data and show that the language includes constructs that enable a domain expert to easily model data of interest in the log extraction step. The language provides sufficient information to extract and transform data from transactional ERP databases to the XES format.

scholarly journals Does laser surface texturing really have a negative impact on the fatigue lifetime of mechanical components?

Friction ◽  
2021 ◽  
Author(s):  
Chia-Jui Hsu ◽  
Andreas Stratmann ◽  
Simon Medina ◽  
Georg Jacobs ◽  
Frank Mücklich ◽  
...  
Keyword(s):  
Boundary Lubrication ◽  
Surface Texturing ◽  
Contact Stresses ◽  
Laser Surface ◽  
Laser Surface Texturing ◽  
Wear Loss ◽  
Textured Surface ◽  
Periodic Patterns ◽  
Rolling Bearings ◽  
Fatigue Lifetime

AbstractLaser surface texturing (LST) has been proven to improve the tribological performance of machine elements. The micro-scale patterns manufactured by LST may act as lubricant reservoirs, thus supplying oil when encountering insufficient lubrication. However, not many studies have investigated the use of LST in the boundary lubrication regime, likely due to concerns of higher contact stresses that can occur with the increasing surface roughness. This study aims to examine the influence of LST on the fatigue lifetime of thrust rolling bearings under boundary lubrication. A series of periodic patterns were produced on the thrust rolling bearings, using two geometrically different designs, namely cross and dimple patterns. Base oil ISO VG 100 mixed with 0.05 wt% P of zinc dialkyldithiophosphate (ZDDP) was supplied. The bearings with cross patterns reduce the wear loss by two orders of magnitude. The patterns not only retain lubricant in the textured pockets but also enhance the formation of an anti-wear tribofilm. The tribofilm generation may be improved by the higher contact stresses that occur when using the textured surface. Therefore, in contrast to the negative concerns, the ball bearings with cross patterns were instead found to increase the fatigue life by a factor of three.

scholarly journals An Efficient Analytical Approach to Visualize Text-Based Event Logs for Semiconductor Equipment

2021 ◽  
Vol 11 (13) ◽  
pp. 5944
Author(s):  
Gunwoo Lee ◽  
Jongpil Jeong
Keyword(s):  
Complex System ◽  
Analytical Approach ◽  
System Behavior ◽  
File Size ◽  
Log Files ◽  
Event Logs ◽  
Hard Disk Space ◽  
Long Time ◽  
Log File ◽  
Runtime Information

Semiconductor equipment consists of a complex system in which numerous components are organically connected and controlled by many controllers. EventLog records all the information available during system processes. Because the EventLog records system runtime information so developers and engineers can understand system behavior and identify possible problems, it is essential for engineers to troubleshoot and maintain it. However, because the EventLog is text-based, complex to view, and stores a large quantity of information, the file size is very large. For long processes, the log file comprises several files, and engineers must look through many files, which makes it difficult to find the cause of the problem and therefore, a long time is required for the analysis. In addition, if the file size of the EventLog becomes large, the EventLog cannot be saved for a prolonged period because it uses a large amount of hard disk space on the CTC computer. In this paper, we propose a method to reduce the size of existing text-based log files. Our proposed method saves and visualizes text-based EventLogs in DB, making it easier to approach problems than the existing text-based analysis. We will confirm the possibility and propose a method that makes it easier for engineers to analyze log files.

scholarly journals Direct Laser Interference Patterning of Diffraction Gratings in Safrofilcon-A Hydrogel: Fabrication and Hydration Assessment

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 679
Author(s):  
Daniel Sola ◽  
Stephan Milles ◽  
Andrés F. Lasagni
Keyword(s):  
Laser Fluence ◽  
Contact Lenses ◽  
Laser Source ◽  
Spatial Period ◽  
Laser Interference ◽  
Periodic Patterns ◽  
Hydration Properties ◽  
Water Contact ◽  
Direct Laser ◽  
Direct Laser Interference Patterning

Refractive index modification by laser micro-structuration of diffractive optical devices in ophthalmic polymers has recently been applied for refractive correction in the fields of optics and ophthalmology. In this work, Safrofilcon-A hydrogel, used as soft contact lenses, was processed by direct laser interference patterning (DLIP) to fabricate linear periodic patterns on the surface of the samples. Periodic modulation of the surface was attained under two-beam interference by using a Q-switched laser source with emission at 263 nm and 4 ns pulse duration. Features of processed areas were studied as a function of both the interference spatial period and the laser fluence. Optical confocal microscopy used to evaluate the topography of the processed samples showed that both structured height and surface roughness increased with laser fluence. Static water contact angle (WCA) measurements were carried out with deionized water droplets on the structured areas to evaluate the hydration properties of DLIP structures. It was observed that the laser structured areas induced a delay in the hydration process. Finally, microstructural changes induced in the structured areas were assessed by confocal micro-Raman spectroscopy showing that at low laser fluences the polymer structure remained almost unaltered. In addition, Raman spectra of hydrated samples recovered the original shape of areas structured at low laser fluence.

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