Tool Edge Research Articles

A new approach for task managing in the fog-based medical cyber-physical systems using a hybrid algorithm

PurposeThis paper aims to offer a hybrid genetic algorithm and the ant colony optimization (GA-ACO) algorithm for task mapping and resource management. The paper aims to reduce the makespan and total response time in fog computing- medical cyber-physical system (FC-MCPS).Design/methodology/approachSwift progress in today’s medical technologies has resulted in a new kind of health-care tool and therapy techniques like the MCPS. The MCPS is a smart and reliable mechanism of entrenched clinical equipment applied to check and manage the patients’ physiological condition. However, the extensive-delay connections among cloud data centers and medical devices are so problematic. FC has been introduced to handle these problems. It includes a group of near-user edge tools named fog points that are collaborating until executing the processing tasks, such as running applications, reducing the utilization of a momentous bulk of data and distributing the messages. Task mapping is a challenging problem for managing fog-based MCPS. As mapping is an non-deterministic pol ynomial-time-hard optimization issue, this paper has proposed a procedure depending on the hybrid GA-ACO to solve this problem in FC-MCPS. ACO and GA, that is applied in their standard formulation and combined as hybrid meta-heuristics to solve the problem. As such ACO-GA is a hybrid meta-heuristic using ACO as the main approach and GA as the local search. GA-ACO is a memetic algorithm using GA as the main approach and ACO as local search.FindingsMATLAB is used to simulate the proposed method and compare it to the ACO and MACO algorithms. The experimental results have validated the improvement in makespan, which makes the method a suitable one for use in medical and real-time systems.Research limitations/implicationsThe proposed method can achieve task mapping in FC-MCPS by attaining high efficiency, which is very significant in practice.Practical implicationsThe proposed approach can achieve the goal of task scheduling in FC-MCPS by attaining the highest total computational efficiency, which is very significant in practice.Originality/valueThis research proposes a GA-ACO algorithm to solve the task mapping in FC-MCPS. It is the most significant originality of the paper.

Providing of roughness during finishing with an edge tool having a small end cutting-edge angle

The mechanism of roughness formation during processing with an edge tool is investigated. It was found that when machining with a tool having a small end cutting-edge angle, scratches are formed as a result of jamming of small chips between the workpiece and the blade in the area of its minor flank. Keywords: finishing, cutting tool, cutting edge angle, built-up, chips, jamming, scratch, roughness, minor flank, sharpening to a point, high-speed cutting. zgs1931@mail.ru

Expert Roundtable: leveraging cutting edge tools to convert I-O data into knowledge

<div class="authors authors-lg"><div class="author"><div class="author-img"><img src="https://cdn.insights.bio/uploads/Sood Pic copy.jpg" data-image="1"></div><div class="author-det"><h3 class="author-name" style="color:#5D538A;">Anil K Sood</h3><h5 class="author-title" style="color:#5D538A;">Professor, Department of Gynecologic Oncology and Reproductive Medicine, UT MD Anderson Cancer Center</h5> Dr Anil K Sood is Professor in the Department of Gynecologic Oncology and Reproductive Medicine at the UT MD Anderson Cancer Center. He holds a joint appointment in Cancer Biology and is co-director of the Center for RNA Interference and Non-Coding RNA at the M. D. Anderson Cancer Center. He is also Director of the multi-disciplinary Blanton-Davis Ovarian Cancer Research Program and co-leads the Ovarian Cancer Moonshot Program. Dr Sood received his medical degree from the University of North Carolina, Chapel Hill. A major and consistent theme of his scientific research has been on understanding human cancer biology and converting lab discoveries into novel therapeutics. His research group has made several seminal research contributions in the fields of tumor microenvironment, nanomedicine, and neuroendocrine effects on cancer biology. Dr Sood has received recognition for his research accomplishments including the Hunter Award, the Margaret Greenfield/Carmel Cohen Excellence in Ovarian Cancer Research Prize, and the GCF/Claudia Cohen Research Foundation Prize for Outstanding Gynecologic Cancer Researcher. He is an elected member of the American Society for Clinical Investigation (ASCI), the American Association for the Advancement of Science (AAAS), and the Association of American Physicians (AAP). Dr Sood was selected as an American Cancer Society Research Professor in 2017. </div></div></div><div class="authors authors-lg"><div class="author"><div class="author-img"><img src="https://cdn.insights.bio/uploads/Prabhakaran_Sandhya_1200x800 - Sandhya Prabhakaran copy.jpg" data-image="1"></div><div class="author-det"><h3 class="author-name" style="color:#00A795;"><strong>Sandhya Prabhakaran</strong></h3><h5 class="author-title" style="color:#00A795;">Applied Research Scientist, Integrated Mathematical Oncology Department, Moffitt Cancer Centre</h5> Dr. Sandhya Prabhakaran is an Applied Research Scientist at the Integrated Mathematical Oncology department, Moffitt Cancer Centre, Florida. Before that she was a Research Scientist at Memorial Sloan Kettering Cancer Centre and Columbia University. Her PhD in Computer Science is from University of Basel and her Masters in Intelligent Systems (Robotics) is from University of Edinburgh. Her research deals with developing statistical theory and Bayesian inference models, particularly to problems in Cancer Biology and Computer Vision. Prior to academics, she was an Assembler programmer working with the Mainframe Operating System (z/OS) at IBM Software Laboratories and has developed Mainframe applications. She has completed 4 out of the 6 World Marathon Majors. </div></div></div><div class="authors authors-lg"><div class="author"><div class="author-img"><strong><strong><strong><img src="https://cdn.insights.bio/uploads/Goldmacher photo.png" data-image="1"></strong></strong></strong></div><div class="author-det"><h3 class="author-name" style="color:#007589;"><strong><strong>Gregory Goldmacher</strong></strong></h3><h5 class="author-title" style="color:#007589;">Executive Director, Clinical Research, Head of Clinical Imaging, Merck Research Laboratories</h5> Greg has been at MSD since 2015. With his team of radiologists and imaging scientists, he oversees the clinical imaging in over 200 clinical trials in oncology and other therapeutic areas. He also leads research in radiomics, artificial intelligence, novel response criteria, tumor growth kinetics, and other innovative approaches to clinical trial imaging. Prior to MSD, he was a senior medical director and head of oncology imaging at a global CRO, and before that in academia. His clinical training was in diagnostic radiology, along with a PhD and postdoctoral work in neuroscience, and business training in finance. In his ‘free’ time, he enjoys playing with his kids, running, and training in the martial arts. </div></div><div class="author"><div class="author-img"><strong><strong><strong><img src="https://cdn.insights.bio/uploads/Sanjabi photo copy.png" data-image="1"></strong></strong></strong></div><div class="author-det"><h3 class="author-name" style="color: rgb(125, 203, 120);"><strong><strong>Shomyseh Sanjabi</strong></strong></h3><h5 class="author-title" style="color: rgb(125, 203, 120);">Principal Scientist, Oncology Biomarker Development, Genentech</h5> Shomyseh Sanjabi, PhD is a Principal Scientist in Oncology Biomarker Development (OBD) at Genentech. She obtained her bachelor’s degree in microbiology and molecular genetics from the University of California, Los Angeles (UCLA) and completed her PhD training with Dr Stephen Smale at UCLA in the department of microbiology, immunology, and molecular genetics elucidating the molecular mechanism of family member specificity among the NF-kappa-B family of transcription factors. She then completed a postdoctoral training in immunobiology at Yale University with Dr Richard Flavell studying the role of TGF-beta and common gamma chain cytokines in CD8 T cell development and function in the context of autoimmunity, anti-pathogen immunity, and cancer immunity. In 2010, she joined the faculty at the Gladstone Institute of Virology and Immunology and UCSF department of microbiology and immunology, where she was the recipient of numerous awards including an NIH New Innovator Award. Her independent academic research focused on using model pathogens and emerging human pathogens, together with preclinical genetic mouse models and human primary tissue samples to study how protective innate and adaptive immune responses are elicited and maintained upon mucosal transmission of viral pathogens. Her passion for human immunology and her vision to apply innovative technologies to study the immune response of patients undergoing cancer immunotherapy brought her to Genentech in 2018. She currently leads the biomarker and translational activities for several early-stage cancer immunotherapy programs. </div></div></div>

Механизм лезвийной очистки металлического проката от окалины

A new purifying method of metal surface cleaning from oxide scale using a special rotating edge tool is described, which allows to solve the problem of increasing the extent of surface purification from oxide scale more efficiently, reliably and effectively.&#x0D; The process of the surface cleaning of flat- rolled products used for the manufacture of hollow sheres from oxide scale by mechanical action of a cutting tool on various layers of oxide scale is simulated.&#x0D; The force required to shift an oxide scale and the boundary conditions of the ratio hold-down pressure of the tool to the workpiece, the friction force in the tool support and the impact force of the scale on the tool, at which it is possible to remove the scale from the rolled surface, are determined.

Three-dimensional finite element simulations of milling carbon/epoxy composites

Mechanical milling is an extensively used finishing process for fiber-reinforced polymer (FRP) composites. To better understand the characteristics in machining FRPs for higher quality and efficiency, various studies have been conducted based on the finite element (FE) method as it can give insight on the mechanisms of material removal during cutting. Yet there is still a lack of three-dimensional FE models suitable for studying the mechanisms involved in the milling of FRPs. This paper developed a 3D meso-scale FE model for simulating CFRP milling by considering the damage behavior of the composites in 3D stress state. A progressive damage model was proposed and implemented using the VUSDFLD subroutine to predict the continuous damage evolution and stiffness degradation of the laminae. The simulated cutting forces and sub-surface damage agreed with the experimental observations. Numerical studies also showed that the failure criterion affected the simulated cutting forces and sub-surface damage. Upon increasing the tool edge radius, the simulated sub-surface damage affected a larger zone beneath the machined surface; however, the simulated cutting force and the sub-surface post-failure-initiation damage area experienced no obvious changes for the studied edge radius range.

PCM assisted reverse electro discharge machining process for pattern generation

ABSTRACT This research work reports about pattern generation using the photochemical machining (PCM) assisted reverse electro discharge machining (EDM) process on an aluminum 6061 workpiece. A mixture of fine powder of copper and tungsten is used to fabricate a green compact tool. A complex shape is generated onto the tool surface and is further implemented to migrate the shaped tool particle onto the work surface. The output parameters are the material deposition rate (MDR), tool wear rate (TWR), edge deviation (ED), and surface roughness (Ra). The pattern is characterized by Field Emission Scanning Electron Microscopy (FESEM) and Energy Disperse Spectroscopy (EDS) analyses. The presence of tungsten particles increases the microhardness of the substrate material. The surface microhardness of the pattern is found to be 362Hv.

Brittle-Ductile Transition and Nano-Surface Generation in Single-Point Diamond Turning of Single-Crystal Germanium

Single-crystal germanium (Ge) has been widely used in infrared optics and ultra-precision components, however, the appearance of alternating brittle and ductile fan-shaped patterns on machined surfaces seriously affects the machined surface quality. The present research focused on the brittle-ductile transition and its effect on the nanosurface generation in single-point diamond turning (SPDT) of (100), (110) and (111) crystal planes of Ge. Face cutting and plunge cutting experiments were performed, the surface anisotropy and brittle-ductile transition regime during cutting were analyzed, and the evolution of crystalline structure were discussed with molecular dynamics (MD) simulation. Theoretical and experimental results show: (1) The anisotropy of the machined surface is closely related to the atomic arrangement order and lattice structure. The anisotropy of the (111) crystal plane is stable while the (110) is unstable. (2) The critical length and depth of both the elastic-ductile and brittle-ductile transition are anisotropic; the depth and length of brittle regions are shallower and shorter than those of ductile regions and proportional to the tool edge radius. (3) The critical depth and thrust force of the elastic-ductile transition obtained in MD simulation can be employed to predict the changing trend of the brittle-ductile transition. (4) The thickness of amorphous layer produced on the machined surface is proportional to the ratio of cut depth to tool edge radius. The crystal orientation of the (111) crystal plane shows the best cutting performance. This paper provides deep insight into the brittle-ductile transition and nanosurface generation in SPDT of Ge.

A Comparison of the Probes with a Cantilever Beam and a Double-Sided Beam in the Tool Edge Profiler for On-Machine Measurement of a Precision Cutting Tool

This paper describes a comparison of the mechanical structures (a double-sided beam and a cantilever beam) of a probe in a tool edge profiler for the measurement of a micro-cutting tool. The tool edge profiler consists of a positioning unit having a pair of one-axis DC servo motor stages and a probe unit having a laser displacement sensor and a probe composed of a stylus and a mechanical beam; on-machine measurement of a tool cutting edge can be conducted with a low contact force through measuring the deformation of the probe by the laser displacement sensor while monitoring the tool position. Meanwhile, the mechanical structure of the probe could affect the performance of measurement of the edge profile of a precision cutting tool. In this paper, the measurement principle of the tool edge profile is firstly introduced; after that, slopes and a top-flat of a cutting tool sample are measured by using a cantilever-type probe and a double-sided beam-type probe, respectively. The measurement performances of the two probes are compared through experiments and theoretical measurement uncertainty analysis.

Evaluation of PSMA-PET Biology-Guided Radiotherapy Sequential Boost to the PSMA-avid Subvolume in the Prostate Region in Low-Volume Advanced Prostate Cancer

Biology-guided radiation therapy (BgRT) is a new technology that aims to deliver radiation based on detecting positron emissions in real time. BgRT combined with prostate specific membrane antigen (PSMA) PET/CT imaging may be an attractive option for prostate cancer patients with low-volume pelvic nodes and distant metastases since all lesions may be treated during the same session. This study investigates the feasibility of BgRT sequential boost to the PSMA-avid subvolume (PAS) in the prostate region. The ratio of standard uptake value (SUV) to background SUV is quantified, with specific focus on adjacent bladder uptake.Patients enrolled in the ProPSMA prospective single-institution clinical trial underwent Ga-68-PSMA-11 PET scan at the time of prostate cancer diagnosis. Those with pelvic node or distant metastases were selected for analysis. PAS gross target volume (GTV) was delineated on the PET component of a PET/CT acquisition by using a PET edge tool in commercially available software. Three dimensional shells of thickness 5 mm, 10 mm and 20 mm were created by expanding the GTV to characterize the uptake background and to determine suitability of BgRT based on these tracking zones. Normalized SUV (nSUV) was calculated as the ratio of SUVmax in the GTV to SUVmean of the adjacent shell. Lesions with nSUV larger than 3 were defined to be suitable for BgRT. An increase in nSUV with increasing shell thickness indicates absence of uptake surrounding the GTV.From the ProPSMA patient cohort of 89 patients, 24 patients had at least one pelvic nodal or distant metastases. PAS GTV volume ranged from 1 cc to 147 cc (median = 25 cc, IQR = 12 cc - 62 cc). GTV SUVmax varied from 6.4 to 80 (median = 21.5; IQR = 14 - 33). nSUV ranged from 3.4 to 21.2 (median = 6.4; IQR = 4.9 - 8.5), from 4.1 to 20.9 (median = 8.6; IQR = 6 - 10.5), and from 2.8 to 31.4 (median = 8.2; IQR = 5.4 - 13.8) in 5 mm, 10 mm, and 20 mm shell, respectively. Moreover, 100%, 100%, and 96% of lesions had nSUV greater than 3 in a shell thickness of 5 mm, 10 mm, and 20 mm, respectively. nSUV increased from the 5 mm shell to the 10 mm shell in 75% of patients and from the 10 mm shell to the 20 mm in 46% patients, indicating the absence of bladder uptake.An nSUV greater than 3 was achieved in more than 95% of all GTVs for all shell thicknesses investigated in this study, which suggests that PSMA-guided BgRT is a feasible modality for sequential boost directed at the dPSMA-avid subvolume in the prostate region. If bladder proximity impacts geometric specificity of BgRT delivery or if greater tumor-to-background contrast is desired, additional refinements may be required. These may include modifications to the BgRT algorithm that enable masking of the bladder. Clinical trial number ACTRN12617000005358.

Modeling cutting edge degradation by chipping in micro-milling

The cutting edges of micro-milling tool undergo degradation with time, in the form of continuous abrasion and intermittent chipping. As a result, the cutting tool looses its original profile and consequently affects the quality of molds and dies manufactured using micro-milling process. This work therefore focuses on understanding the physics and mechanism of tool wear in micro-milling as function of tool life, and to model the transient degradation of cutting tool, which was not investigated in-depth in the literature. Extensive micro-milling experiments were done till the end of tool life, to investigate cutting edge degradation. Further, analytical as well as empirical models were developed to predict continuous abrasion interrupted by chipping, and to determine cutting edge profiles as a function of tool life. The abrasion wear model involved modifying Archard’s equation and evaluating tool wear coefficient empirically using a novel pin-on-disk device. The interrupted chipping wear phenomenon during micro-milling was identified by locating sudden drop in resultant forces on the tool. The chipping wear was then modeled using the dimensions of the chipped portions, extracted from the tool images captured in-situ. It was observed from the experiments that the length (C) of the chipped portions of the cutting edges was between 15.76 to 96 μm, whereas, their width (H) was between 7 to 29 μm, and they were found to have a positive correlation. The chipping load estimated from the resultant force, and the load inclination angle evaluated from the chipping model were found to have an inverse correlation, and varied between 1.23 to 3.75 N, and 69 to 25° respectively. The proposed abrasion and chipping wear model jointly gave transient progression of total volumetric tool wear area, and consequent cutting edge profiles over the tool-life cycle. The proposed tool wear model predicted the total wear within 9.3% of the experimental values.

Evaluation on the performance of hybrid textured coated tool under conventional cooling environment

During the process of cutting aluminum alloy with WC/Co coated tools, severe adhesion and wear exist on the tool-chip contact interface, which are the major factors leading to failure of cutting tools. To address this problem and extend the service life of cutting tools, this study introduced surface textures into coated tools, trying to integrate the anti-friction properties of micro-textures with the wear resistance properties of coating to improve tribological characteristics of tools surface. Firstly, hybrid texture consisting of micro-scale pits and micro-scale grooves were fabricated on the rake surface close to the main cutting edge of carbide tools by picosecond laser. Subsequently, the textured tools were deposited with hard-coating CrAlN via physical vapor deposition (PVD) technology, and the hybrid textured CrAlN coated tool (MPG-T) was obtained eventually. Other texture combinations included micro-scale pits and micro-scale grooves distributed in the tool-chip contact zone. Wet cutting experiments were carried out with these prepared tools. Results showed that MPG-T tool performed better in cutting forces, friction coefficient, tool adhesion and wear on the rake face and the flank face, chip morphology compared with micro-scale pitted coated tool (MP-T), micro-scale grooved (MG-T) and conventional coated tool (CCT). Moreover, the corresponding synergistic mechanisms of hybrid texture and coating were proposed. It’s suggested that applying the results to actual industries can enhance the performance of coated tools in machining of 6061 aluminum alloy.

Dynamics and chatter stability of crest-cut end mills

Chatter is a major problem reducing part quality and productivity in milling operations. In order to improve productivity with standard end mills, higher cutting speeds must be employed to reach deeper stability lobes. However, due to machine tool and machinability limitations in cutting hard-to-cut materials, higher cutting speeds are not feasible. For those cases, special milling tools such as variable pitch and crest-cut cutters offer an alternative method to increase productivity. Due to their special geometry crest-cut tools introduce large stable regions at low-speed ranges where variable pitch tools provide narrow stability lobes. This advantage is caused by the wavy edge shape along the cutting edges of the crest-cut tools. In this study, stability of crest-cut tools is studied using the semi-discretization method by implementing a novel geometrical modeling approach enabling accurate cutting force predictions verified experimentally for the first time in literature. Based on the proposed model, the effect of edge wave geometry on stability is analyzed and compared with standard and variable pitch tools. Results show that the crest-cut tools introduce significant advantages in terms of stability limit and stable zones compared to other types of end mills. This superiority results in higher productivity as well as higher robustness at a different cutting speed zones. Finally, a guideline is presented for selection of the best crest-cut tool geometry for desired operating conditions.

Experiment and Modeling of Milling Force Based on Tool Edge Preparation

Experiment and Modeling of Milling Force Based on Tool Edge Preparation

Experimental Investigation on Machinability of Titanium Alloy by Laser-Assisted End Milling

The Machining of titanium alloys is challenging because of their high strength, low thermal conductivity, high chemical reactivity, and high stresses at the cutting tool edges. Laser-assisted machining is an effective way to improve the machinability of titanium alloys. This paper presents an experimental investigation of the machinability of cutting force and surface roughness in laser-assisted end milling of titanium alloy Ti-6Al-4V. The absorptivity of Ti-6Al-4V was determined by conducting preheating experiments using a high-power diode laser with a wavelength of 940–980 nm. A thermal analysis was performed using the finite element method to predict temperature distribution. The depth of cut was determined where tensile strength decreased sharply, and the predicted surface temperature is presented in the analysis results. The experiments were performed with conventional machining and laser-assisted machining. Surface roughness, tool wear, and cutting force were evaluated. In contrast to the results of conventional end milling, laser-assisted end milling improved surface roughness. Moreover, laser-assisted end milling proved more effective than conventional end milling in terms of cutting tool damage. Our results proved that heat assistance significantly influenced the magnitude of the cutting forces—while the actual reduction in forces varied slightly depending on the force component, cutting tool, and cutting conditions, force components showed a reduction of roughly 13–46%.

Investigation of tool-workpiece contact rate and milling force in elliptical ultrasonic vibration-assisted milling

Elliptical ultrasonic vibration-assisted milling (EUVAM) is widely used as an efficient processing method for hard-to-machining materials such as titanium alloy, superalloy, and hard-brittle materials. To uncover the mechanism of the intermittent cutting characteristics in EUVAM, the tool-workpiece contact rate model is developed by combining with the kinematic relationship between the tool edge and the workpiece in the process. According to the analysis of the contact rate model, the phenomenon that the contact rate increases rapidly with the time-varying tooth position angle in one-dimensional ultrasonic vibration assisted milling can be improved in EUVAM. In addition, considering the variation of window function and undeformed cutting thickness, a force model is established. And the experiment of EUVAM is performed to verify the model of ultrasonic milling force, and the influence of process parameters (amplitude, cutting speed, feed rate and cutting depth) on ultrasonic milling force is also analyzed.

Systemology of objects and processes in digitalization of the life cycle of engineering products

The main methods of classification and coding in mechanical engineering are studied from the systemic point of view, their main characteristics are considered. When analyzing the systemology of classification of machines of various functional purposes, the absence of a unified methodological approach in constructing the classification and in coding the products is shown. In the existing classifications, products are considered constructively only as objects of operation, and the other stages of their life cycle are not affected. As a result of the system analysis, a unified methodological approach is proposed for constructing classifications, coding and unification of products for various functional purposes, reflecting the features of all stages of their life cycle. For the production stages of the life cycle, a system of classifications using various coding methods is considered: a description of structural and technological elements formed by the tool edges, a sequence of numbers, taking into account signs; a description of the surfaces formed by tool movements, in numbers, indicating the directions of feed movements; and to describe complex-profile surfaces and a combination of long-range elements, their combination is used. The expediency of using each of the classifications in real production conditions is determined by the statistics of use of structural and technological elements and surfaces, as well as of tools that form them.

Experimental investigation of microtextured cutting tool performance in titanium alloy via turning

This study aimed to prevent the harmful consequences of the turning process. The use of micro-textured cutting inserts with a femtosecond laser an innovative efficient method to decrease chip adhesion to cutting of edge tools during titanium alloy (Ti6Al4V) turning was studied. Additionally, the effects of different micro-pattern geometries and sizes on the machining capacity of coated WC/Co cutting inserts in turning experiments with titanium–aluminium–nitride (TiAlN) were investigated based on various lubrication processes. The surface states of the micro-patterned TiAlN-coated inserts were analysed using scanning electron microscopy and optical microscopy. Subsequently, machining and measured tests on the titanium alloy were performed using the developed cutting tools. Tungsten carbide tools with textured cutting surfaces and different microstructures were fabricated, and their behaviours were compared with those of conventional coated tools. Thrust, cutting, and feed cutting force values were measured during machining using a three-component dynamometer. Based on the present investigation, the cutting tool with a cross texture exhibited greater reduction of machining forces, friction coefficients, and tool wear.

Experimental Study on Fabrication of CVD Diamond Micro Milling Tool by Picosecond Pulsed Laser.

Because of the many advantages of high-precision micromachining, picosecond pulsed lasers (PSPLs) can be used to process chemical-vapor-deposited diamonds (CVD-D). With the appropriate PSPL manufacturing technique, sharp and smooth edges of CVD-D micro tools can be generated. In this study, a PSPL is used to cut CVD-D. To optimize PSPL cutting, the effects of its parameters including fluence, pulse pitch, and wavelength on the cutting results were investigated. The results showed that the wavelength had the greatest impact on the sharpness of CVD-D. With PSPL cutting, sharp cutting edges, and smooth fabricated surfaces of the CVD-D, micro tools were achieved. Finally, the fabrication of CVD-D micro milling tools and micro milling experiments were also demonstrated.

Experimental Study on Micro-Grinding of Ceramics for Micro-Structuring

In this study, micro-grinding was performed to investigate the machining characteristics of alumina and zirconia. The machining of ceramics remains highly challenging owing to their properties, such as high brittleness and wear resistance, which leads to a shorter tool life and high machining costs. Polycrystalline diamond (PCD) was selected as the tool material, as it is suitable for machining hard and brittle materials, and micro-electrical discharge machining (EDM) was used to fabricate PCD micro-tools. When using a resistor-capacitor generator circuit in micro-EDM, the discharging energy is related to the working capacitance, and by controlling the working capacitance, the different edge radii and the surface roughness of the tool can be easily achieved. The feed rate, depth of cut, and rotation speed were set as experimental parameters to investigate the grinding characteristics of the ceramics. During the experiment, the grinding force and roughness of the bottom surface were monitored, and the roughness of the machined surfaces was measured using a three-dimensional surface profiler. A working capacitance of 1000 pF was used to fabricate a tool with an edge radius of 3.5 µm. The lower radius of the tool edge resulted in a decrease of the cutting force by 50% at most and a surface roughness of 19 nm Ra.

Edge and anomaly detection of brain magnetic resonance images in a distributed environment

AbstractToday, all scientific advancements related to medical image processing aim to develop a unique computational model. The latter will mimic the way humans interpret images. In the present paper, we propose a formal approach biologically inspired by the human natural vision system’s mechanisms. To that end, we use the spiking neural network model for edge detection in brain MRI images. The optimal results provided by this last step increase performance, and facilitate the process of anomaly detection. For that, we have developed a tool called Edge and Anomaly Detection of Brain MRI Images in Distributed Environment (EADBMIDE). It is tested on an MRI brain tumour dataset, which shows the effectiveness of the proposed methods. Each stage in this tool is compared separately with similar approaches in the literature. The obtained results show a significant improvement, making this a recommended tool for edge and anomaly detection methods in MRI images.