Influence of Process Parameters and Responses on Performance of CNC Machine Turning Operation by using Multiple Regression Method

Influence of process parameters and responses on performance of CNC machine turning operation on EN-31 steel material in turning operations. This study aims at determining the factors and their interaction that may affect the responses. The response such as surface finish is greatly influenced by factors such as speed, feed rate and depth of cut. Multiple regression method is used to analyze the performance of process parameter on response such as surface finish rate is done on CNC lathe on EN31 sample. Hence, multiple regression model for surface finish has been developed, as a function of spindle speed, feed rate and depth of cut.. It was concluded that surface finish is highly dependent on spindle speed. DOI: 10.17762/ijritcc2321-8169.150518

Skeletal effects of mini-implant assisted rapid palatal expansion (MARPE) on the sagittal dimensions of the maxilla an in-vivo cone-beam computed tomography (CBCT) study

ABSTRACT Introduction: Transverse discrepancies of the maxilla is one of the most prevalent skeletal problems. Due to the drawbacks of conventional RPE and invasive surgical expansion, alternative methods were developed, such as Mini Implant-supported rapid maxillary expanders (MARPE). Many studies reported by Haas, Davis and Kronman, Akkaya et al. regarding the maxillary response after MARPE on the sagittal dimensions were inconclusive. Aim: The aim of this study was to analyze the sagittal effects on the maxilla after Mini Implant assisted rapid palatal expansion (MARPE) in adolescents. Materials and methods: Pre-treatment CBCT images (T1) were taken as a standard initial record for all patients and post-treatment CBCT (T2) was taken three months in retention after expansion with MARPE. The parameters SNA angle, Frankfort horizontal plane to NA angle, A-N perpendicular in mm, ANS – PNS (in mm) were measured and calculated for evaluation of the sagittal maxillary changes. Comparisons were then made between the two treatment groups at T1, T2 and T2 - T1. Results: A positive increase was seen from pretreatment to post-treatment in both angular and linear measurements showing the significant sagittal skeletal change. Conclusion: The study found a statistically significant forward displacement of maxilla after transverse skeletal expansion in adolescent patients with transverse problems achieved through MARPE

The role of anthropogenic forcings on historical sea‐level change in the Indo‐Pacific warm pool region

Detecting and attributing sea‐level rise over different spatiotemporal scales is essential for low‐lying and highly populated coastal regions. Using the Detection and Attribution Model Intercomparison Project (DAMIP) from the Coupled Model Intercomparison Project Phase 6, we evaluate the role of anthropogenic forcing in sea‐level change in the historical (1950–2014) period in the Indo‐Pacific warm pool region. We use three models that have at least 10 ensemble members, corresponding to different DAMIP simulations. We determined the changes in regional sea level from both natural and anthropogenic forcings. Our results demonstrate: (a) the emergence of an anthropogenic footprint on regional sterodynamic sea‐level change has a large spatiotemporal diversity over the Indo‐Pacific warm pool region with the earliest emergence in the western Indian Ocean; (b) a significant rise in dynamic sea level (DSL) (up to 25 mm) and thermosteric (up to 40 mm) sea level over the western Indian Ocean due to greenhouse gas forcing; (c) a positive Indian Ocean Dipole‐like pattern in the DSL changes over the tropical Indian Ocean; (d) a significant increase in the halosteric contribution to sea‐level rise in the Indo‐Pacific warm pool region, and (e) a pronounced rise of manometric sea level (up to 20 mm) over shallow oceans and coastal regions in recent decades. These results provide a comprehensive spatiotemporal analysis of the attribution of anthropogenic factors to sea‐level changes in the Indo‐Pacific warm pool region

Multifunctional light beam control device by stimuli-responsive liquid crystal micro-grating structures

There is an increasing need to control light phase with tailored precision via simple means in both fundamental science and industry. One of the best candidates to achieve this goal are electro-optical materials. In this work, a novel technique to modulate the spatial phase profile of a propagating light beam by means of liquid crystals (LC), electro-optically addressed by indium-tin oxide (ITO) grating microstructures, is proposed and experimentally demonstrated. A planar LC cell is assembled between two perpendicularly placed ITO gratings based on microstructured electrodes. By properly selecting only four voltage sources, we modulate the LC-induced phase profile such that non-diffractive Bessel beams, laser stretching, beam steering, and 2D tunable diffraction gratings are generated. In such a way, the proposed LC-tunable component performs as an all-in-one device with unprecedented characteristics and multiple functionalities. The operation voltages are very low and the aperture is large. Moreover, the device operates with a very simple voltage control scheme and it is lightweight and compact. Apart from the demonstrated functionalities, the proposed technique could open further venues of research in optical phase spatial modulation formats based on electro-optical materials.This work was supported by the Comunidad de Madrid and FEDER Program (S2018/NMT-4326), the Ministerio de Economía y Competitividad of Spain (TEC2016-77242-C3-1-R and TEC2016-76021-C2-2-R), the FEDER/Ministerio de Ciencia, Innovación y Universidades and Agencia Estatal de Investigación (RTC2017-6321-1, PID2019-109072RB-C31 and PID2019-107270RB-C21). The authors also acknowledge the support by the Ministry of National Defense of Poland (GBMON/13-995/2018/WAT), Military University of Technology (Grant no. 23-895)

Detecting the anthropogenic footprints on sea level over the Southeast Asia region

Anthropogenic climate change induced sea level rise exerts significant stress on coastal communities and low-lying islands, particularly in Southeast Asia (SEA). SEA is already exposed to a wide range of natural hazards; sea level rise poses an additional threat to it. It is therefore critical to understand the past sea level changes in SEA, thereby enabling a better understanding of future sea-level projections. However, changes in sea level at the local scale vary from the global scale and are subject to a wide range of driving factors. These driving factors include natural, as well as anthropogenic forcings caused by human influence. However, separating the effects of natural climate variability from anthropogenic forcing on the sea-level rise over the SEA region is not well understood, and still remains a challenge. In this project, I focus on: (1) examining the sea level trend from satellite observations and tide gauge records, and (2) attributing the anthropogenic factors on sea level changes during the historical period (1950-2014) using the Detection and Attribution Model Intercomparison Project (DAMIP) of Coupled Model Intercomparison Project Phase 6 (CMIP6). Based on the availability of at least ten ensemble members across different DAMIP simulations, I selected CanESM5, CNRM-CM6, and IPSL-CM6A models. Using the ensemble mean simulations from these models I studied the attribution of different anthropogenic forcings (e.g., greenhouse gas, aerosol) and natural forcings to address the total historical changes in sea level. I examined the relative changes in thermosteric sea level. Further, I estimated the changes (1985-2014 minus 1950-1979) and trends in the spatial patterns of the dynamic component of sea level. I found that overall greenhouse gas forcing increases the thermosteric and dynamic sea level. Further analysis of surface wind pattern changes suggests the dominance of easterly winds in the eastern Indian Ocean to reduce the dynamic sea level near the Indonesian coast in recent decades. My results provide a comprehensive spatio-temporal understanding of the attribution of anthropogenic factors in sea-level rise over the SEA region. Despite interannual-to-decadal variability, results suggest the dominance of anthropogenic factors and underlying mechanisms in sea-level rise that has occurred in recent decades.Bachelor of Engineering (Mechanical Engineering

Solving Fresnel equation for refractive index using reflected optical power obtained from Bessel beam interferometry

This work demonstrates an interferometric technique to estimate the reflected powers from dielectric interfaces and the reflection coefficient using the Fresnel equation for measurement of the refractive index (RI) of liquid samples. It uses low-coherence common-path optical interferometry that is commonly used for optical imaging. A uniquely designed optical fiber tip generating a high-quality non-diffractive Bessel beam probes liquid samples in a glass container non-invasively. The light reflected from different interfaces of the container is recollected by the same optical fiber tip. The reflected beams interfere with the reference beam generated at the fiber tip itself. This interference spectrum is further processed using fast-Fourier transform to measure reflected powers from the respective interfaces. The acquired powers are used to solve the Fresnel equation to find RI of liquid samples. As a proof of concept, experiments have been performed on several liquid samples including turbid media such as blood. This non-invasive interferometric technique could also be an ideal example confirming the Fresnel equation for reflection of light. Unlike other optical fiber-based RI sensors, this technique does not require temperature compensation. The method can be employed for inspection of the production process in terms of RI in pharmaceutical and chemical process plants, etc

Encaved optical fiber nano-probe exciting whispering gallery mode resonance with focused far off-axis beam

International audienceThis paper demonstrates whispering gallery mode (WGM) resonance with the help of an encaved optical nano-probe developed inside an optical fiber tip cavity. The nano-probe generates a tightly focused beam with a spot-size of ∼3 µm. A barium titanate microsphere is placed besides the optical axis inside the cavity. The focused beam remains off-axis of the microresonator and excites the WGM. The off-axis excitation shows unique resonating properties depending on the location of the resonator. A resonant peak with quality factor as high as Q ∼7 × 10 4 is achieved experimentally. Another design with a shorter cavity length for a bigger resonator is also demonstrated by embedding a bigger microsphere on the cleaved fiber tip surface. The optical probe holds great potential for photonic devices and is ideal for studying morphology-based scattering problems

Common-Path Optical Coherence Tomography Using the Bessel Beam From Negative Axicon Optical Fiber Tip

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The Relationship Between Uterine Artery two-dimensional Color Doppler Measurement and Pregnancy Outcome: A Prospective Observational Study

Abstract Background: The purpose of the study was to evaluate the role of uterine blood flow parameters measured by uterine artery two-dimensional (2D)-power color doppler (PCD) ultrasound in predicting fertility outcomes in women undergoing IVF-ET cycles. Methods: In this prospective observational study, a total of 188 infertile women who underwent IVF-ET cycles were investigated. Uterine artery 2D-PD measurements were taken during early follicular phase and on day of trigger. Pulsatility Index (PI), Resistant Index (RI), Peak Systolic Velocity (PSV), and Systolic/Diastolic ratio (S/D) were measured. Statistical correlation was sought between the doppler parameters and fertility outcomes. Results: The pregnancy rate was 40.43% (76/188). The women who conceived (n= 76) (Group A) were found to have mean age of 31.2±3.9 years whereas the nonpregnant group of women (n=112) (Group B) had mean age of 31.45±4.25 years. The mean PI measurements subsequently during early follicular phase and on the day of hCG trigger between group A and group B were comparable (2.09±1.15 versus 1.9±0.95; p=0.385 and 1.86±1.12 versus 2. 03±1.0; p=0.192, respectively). No significant changes in the uterine artery PSV values and S/D values and RI were noted during the cycle. Conclusion: Uterine artery doppler evaluation in women undergoing IVF cycles was not predictive of the pregnancy outcomes