18 research outputs found
MRR and TWR study of powder mix EDM and pure EDM based on response surface methodology
Powder-mixed electrical discharge machining (PMEDM) enhances the machined surface's output by combining dielectric fluid with various types of powders. This process is quickly gaining acceptance in the electrical discharge machining (EDM) sector. The purpose of this study is to determine whether a dielectric fluid containing tantalum carbide (TaC) powder can improve the material removal rate
(MRR) also, lessen tool wear rate (TWR) during the subsequent EDM machining of stainless steel material. The material removal rates, tool wear rate, and mathematical models of two different EDM mediums were examined during the machining. For the machining procedure, kerosene dielectric fluid containing TaC powder at a concentration of 25.0 g/L was used. The machining input variables were used peak current, pulse on time, and pulse off time. We determined how these variables affected the MRR and TWR of the copper-based EDMed electrode tools. During electrical
discharge machining, the MRR for stainless steel (SUS 304) was increased by MRRPMEDM by 4.3 to 5.3% and TWRpEDM was reduced by 37.9% when TaC powder additive was used. Optimized results also show that TWR and maximum MRR can be achieved at 81.98% and 13.779mm3/min respectively with 83.50% desirability whenever the pulse on-time and pulse off-time are 6.20 µs and 6.50 µs respectively. The models are reliable and can be used to forecast the machining responses within the experimental region, it can be said. The MRR and TWR model for EDM with TaC powder additive (MRRPMEDM) identifies current as the most significant factor, followed by pulse on time and off-time
THE Visual Outcomes and Prognostic Factors Associated With Open-Globe Injuries among the Pakistani Population
Objective: To determine the visual outcomes and prognostic factors associated with open globe-injuries in patients attending Sindh Institute of Ophthalmology and Visual Sciences (SIOVS), Hyderabad, Pakistan.
Methods: A prospective cross-sectional study was conducted at Sindh Institute of Ophthalmology and Visual Sciences (SIOVS), Hyderabad from January 2022 to February 2023. All patients irrespective of age and gender attended the institute with open globe injury were enrolled. Visual outcomes of open-globe injury were recorded as length of wound and lens status. Complications associated with open-globe injury were also noted.
Results: Of 336 patients, the mean age of the patients was 17.6 ± 15.6 years. There were 231 (68.7%) males and 105 (31.3%) females. The most common object of injury was stick/thorn and metal/iron i.e., 117 (34.8%) and 105 (31.3%) respectively. Center of cornea/visual axis involvement was observed in 207 (61.6%) patients. The mean length of the wound was 6.28 ± 3.65 mm. Status of the lens showed an intact lens in 140 (41.7%) patients and traumatic cataract with intact/rupture of capsule in 196 (58.3%) patients. A significant association between the length of the wound and the status of the lens was found with the object of injury (p-value <0.001), and center of cornea/visual axis involvement (p-value <0.001).
Conclusion: In this study, the majority of patients with globe injuries were younger. Object of injury and center of cornea/visual axis involvement were two prognostic factors that were significantly associated with visual outcomes of globe injuries
Morphological Classification of Radio Galaxies using Semi-Supervised Group Equivariant CNNs
Out of the estimated few trillion galaxies, only around a million have been
detected through radio frequencies, and only a tiny fraction, approximately a
thousand, have been manually classified. We have addressed this disparity
between labeled and unlabeled images of radio galaxies by employing a
semi-supervised learning approach to classify them into the known
Fanaroff-Riley Type I (FRI) and Type II (FRII) categories. A Group Equivariant
Convolutional Neural Network (G-CNN) was used as an encoder of the
state-of-the-art self-supervised methods SimCLR (A Simple Framework for
Contrastive Learning of Visual Representations) and BYOL (Bootstrap Your Own
Latent). The G-CNN preserves the equivariance for the Euclidean Group E(2),
enabling it to effectively learn the representation of globally oriented
feature maps. After representation learning, we trained a fully-connected
classifier and fine-tuned the trained encoder with labeled data. Our findings
demonstrate that our semi-supervised approach outperforms existing
state-of-the-art methods across several metrics, including cluster quality,
convergence rate, accuracy, precision, recall, and the F1-score. Moreover,
statistical significance testing via a t-test revealed that our method
surpasses the performance of a fully supervised G-CNN. This study emphasizes
the importance of semi-supervised learning in radio galaxy classification,
where labeled data are still scarce, but the prospects for discovery are
immense.Comment: 9 pages, 6 figures, accepted in INNS Deep Learning Innovations and
Applications (INNS DLIA 2023) workshop, IJCNN 2023, to be published in
Procedia Computer Scienc
Analysis and Modeling of Tool Wear Rate in Powder Mix EDM and Pure EDM Using Central Composite Design
The process of using dielectric fluid combined with different types of powders to improve the output of the machined surface is known as powder-mixed electrical discharge machining (PMEDM). In the electrical discharge machining (EDM) industry, this procedure is quickly gaining popularity. This investigation's goal is to ascertain whether tantalum carbide (TaC) powder-mixed dielectric fluid can reduce tool wear during the subsequent EDM machining of stainless-steel material. Two different EDM medium's tool wear rates and mathematical models were investigated during the machining. TaC powder at a concentration of 25.0 g/L in kerosene dielectric fluid was used for the machining process. The peak current, pulse on time, and pulse off time were the machining variables used. These variables' effects on the copper based EDMed electrode tools TWR were identified. The TWR for stainless steel (SUS 304) during electrical discharge machining was reduced by 37.9% when TaC powder additive was used, according to the results, demonstrating the effectiveness of this alternative method for reducing tool wear. The most influential factor, according to the tool wear ratio model for EDM with TaC powder additive (TWRPMEDM), is current, followed by pulse on-time and pulse off-time
Analysis and modeling of surface roughness in powder mix EDM and pure EDM using central composite design
Conventional surface modification methods, such as ion insertion and laser surface melting, have recently seen growing importance in the innovative usage of the electrical discharge machining process (EDM) as a competitive substitute. Surface composition and properties are affected by several factors, including erosion of work materials and tool materials during the process, as well as the formation of plasma channels from the vaporized materials. This indicates that, under certain machining conditions, deliberate materials transfer may be possible using either a composite electrode by scattering metallic powders in a dielectric or a combination of the two. However, the traditional electrode has not been very successful in the surface modification process. Although it has been considered, expanding research into the use of powder additives through EDM techniques to enhance the level of surface modification is lacking. In addition, the pulse interval is not included in the existing works that examine the impact of technique parameters on surface modification. Because of this, a thorough optimization of the process has not been possible to characterize the connection between the independent variables under control and the machining parameters. To take full advantage of the benefits offered by EDM, it is necessary to learn more about the missing links between the process and its desired outcomes, such as whether or not surface alloying of metallic materials using EDM is feasible and what controls should be used for the various variables involved. The purpose of this study was to assess the efficiency of EDM-based surface alloying of stainless steel using Tantalum Carbide (TaC) powder as an additive by measuring the resulting surfaces' roughness (SR). It was found that RaPMEDM 11 μm recorded at current 5A and on-time 6.30 μs, off-time 7.00 μs with powder concentration 25g/L. The RaPMEDM is easy to predict by controlling factor current (A) and on-time (B). At the higher current of 7.25A, RaPMEDM showed to decrease slightly. This result justifies TaC powder starts to control and modify the surface of stainless steel at a high factor current. In the case of without additives RaEDM, at maximum current 5 A, on-time 6.26 μs, and off-time 7 μs, RaEDM recorded 7 μm. Although it provided the highest Ra compared to RaPMEDM
THE Visual Outcomes and Prognostic Factors Associated With Open-Globe Injuries among the Pakistani Population
Objective: To determine the visual outcomes and prognostic factors associated with open globe-injuries in patients attending Sindh Institute of Ophthalmology and Visual Sciences (SIOVS), Hyderabad, Pakistan.Methods: A prospective cross-sectional study was conducted at Sindh Institute of Ophthalmology and Visual Sciences (SIOVS), Hyderabad from January 2022 to February 2023. All patients irrespective of age and gender attended the institute with open globe injury were enrolled. Visual outcomes of open-globe injury were recorded as length of wound and lens status. Complications associated with open-globe injury were also noted.Results: Of 336 patients, the mean age of the patients was 17.6 ± 15.6 years. There were 231 (68.7%) males and 105 (31.3%) females. The most common object of injury was stick/thorn and metal/iron i.e., 117 (34.8%) and 105 (31.3%) respectively. Center of cornea/visual axis involvement was observed in 207 (61.6%) patients. The mean length of the wound was 6.28 ± 3.65 mm. Status of the lens showed an intact lens in 140 (41.7%) patients and traumatic cataract with intact/rupture of capsule in 196 (58.3%) patients. A significant association between the length of the wound and the status of the lens was found with the object of injury (p-value <0.001), and center of cornea/visual axis involvement (p-value <0.001). Conclusion: In this study, the majority of patients with globe injuries were younger. Object of injury and center of cornea/visual axis involvementwere two prognostic factors that were significantly associated with visual outcomes ofglobe injuries
A synaptic corollary discharge signal suppresses midbrain visual processing during saccade-like locomotion
Abstract In motor control, the brain not only sends motor commands to the periphery, but also generates concurrent internal signals known as corollary discharge (CD) that influence sensory information processing around the time of movement. CD signals are important for identifying sensory input arising from self-motion and to compensate for it, but the underlying mechanisms remain unclear. Using whole-cell patch clamp recordings from neurons in the zebrafish optic tectum, we discovered an inhibitory synaptic signal, temporally locked to spontaneous and visually driven locomotion. This motor-related inhibition was appropriately timed to counteract visually driven excitatory input arising from the fish’s own motion, and transiently suppressed tectal spiking activity. High-resolution calcium imaging revealed localized motor-related signals in the tectal neuropil and the upstream torus longitudinalis, suggesting that CD enters the tectum via this pathway. Together, our results show how visual processing is suppressed during self-motion by motor-related phasic inhibition. This may help explain perceptual saccadic suppression observed in many species
Internet of Things as Intimating for Pregnant Women’s Healthcare: An Impending Privacy Issues
Ingeniously, the innovations are taking place in current medical era, where IoT is a key and its related technology plays a dynamic role in pregnant women care taking inside hospital and outside. IoT ensure the effective and efficient care of pregnant women in any environment because intelligent tiny devices like RF-Tags, sensors are attached with pregnant women, and all the activities of pregnant women can be monitored by professional medical staff from anywhere and anytime. The usage of these advanced technologies in pregnant women care environment, absolutely eradicates the pregnancy complications and harmful incidents, but also raises privacy, religious, ethical, legal and social issues. The purpose of this paper is to discuss the usage of IoT in pregnant women healthcare environments and articulates endorsements to promote research then can guarantee that the pregnant women’s privacy is preserved. DOI : http://dx.doi.org/10.11591/telkomnika.v12i6.422
Acute hyperglycemia, a rabble-rouser or innocent bystander? A prospective analysis of clinical implications of acute hyperglycemia in STE-ACS patients
Abstract Background Acute hyperglycemia is considered an independent prognosticator of both in-hospital and long-term outcomes in patients with acute coronary syndrome (ACS). This study aimed To analyze the incidence of acute hyperglycemia and its impact on the adverse in-hospital outcome in patients with STE-ACS undergoing primary percutaneous coronary intervention (PCI). Methods In this study, we enrolled patients presenting with STE-ACS and undergoing primary PCI at a tertiary care cardiac center. Acute hyperglycemia was defined as random plasma glucose (RBS) > 200 mg/dl at the time of presentation to the emergency room. Results Of the 4470 patients, 78.8% were males, and the mean age was 55.52 ± 11 years. In total, 39.4% (1759) were found to have acute hyperglycemia, and of these, 59% (1037) were already diagnosed with diabetes. Patients with acute hyperglycemia were observed to have a higher incidence of heart failure (8.2% vs. 5.5%; p < 0.001), contrast-induced nephropathy (10.9% vs. 7.4%; p < 0.001), and in-hospital mortality (5.7% vs. 2.5%; p < 0.001). On multivariable analysis, acute hyperglycemia was found to be an independent predictor of mortality with an adjusted odds ratio of 1.81 [1.28–2.55]. Multi-vessel disease (1.73 [1.17–2.56]), pre-procedure left ventricular end-diastolic pressure (LVEDP) (1.02 [1.0-1.03]), and Killip class III/IV (4.55 [3.09–6.71]) were found to be the additional independent predictors of in-hospital mortality. Conclusions Acute hyperglycemia, regardless of diabetic status, is an independent predictor of in-hospital mortality among patients with STE-ACS undergoing primary PCI. Acute hyperglycemia, along with other significant predictors such as multi-vessel involvement, LVEDP, and Killip class III/IV, can be considered for the risk stratification of these patients