Statistical analysis of sand grain/bed collision process recorded by high-speed digital camera

The o-rings in ball retained overdentures deteriorate with time and need replacement to restore the retentive quality. We evaluated retrospectively the mechanical properties of o-rings after 3 years in function in one and two-piece implant-supported overdentures. The o-rings were retrieved from one-piece (Myriad snap, Equinox-Straumann, 3.3 x 13mm) and two-piece (Neo Biotech, 3.3 x 13mm) implant-supported overdenture patients. A total of 16 pairs of matrices were tested for wear, type of damage and elasticity using Pin on Disc method, USB Digital Camera in 30x zoom and Universal Tensile Machine respectively. The statistical analysis for independent groups were done with the Mann-Whitney U test. Assessment of used O-rings showed 84% more wear in the two-piece system with an abrasive type of damage while 46% wear in the one-piece system with a compressive type of damage. The o-rings in one-piece system showed increase in elongation and maximum displacement to 2% and 7% respectively, while two-piece system showed decrease in elongation and maximum displacement by 13% and 6% respectively. In one-piece system, the loss of retention was more with slow wear rate and in two-piece system, the wear resistance of O-rings decreased due to increased stiffness. Further studies to evaluate the changes in O-ring with increased sample size and at interval 1 year will pave way for insight into the progressive changes in the mechanical properties of an O-ring.

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Flank Wear Modelling in High Speed Hard Milling of AISI D2 Steel

International Journal of Engineering Materials and Manufacture ◽

10.26776/ijemm.05.02.2020.03 ◽

2020 ◽

Vol 5 (2) ◽

pp. 50-54

Author(s):

Muataz Al Hazza ◽

Khadijah Muhammad

Keyword(s):

Statistical Analysis ◽

Wear Rate ◽

Taguchi Method ◽

Feed Rate ◽

High Speed ◽

Flank Wear ◽

Cutting Speed ◽

Depth Of Cut ◽

High Speed Machining ◽

Aisi D2

High speed machining has many advantages in reducing time to the market by increasing the material removal rate. However, final surface quality is one of the main challenges for manufacturers in high speed machining due to the increasing of flank wear rate. In high speed machining, the cutting zone is under high pressure associated with high temperature that lead to increasing of the flank wear rate in which affect the final quality of the machined surface. Therefore, one of the main concerns to the manufacturer is to predict the flank wear to estimate and predict the surface roughness as one of the main outputs of the machining processes. The aim of this study is to determine experimentally the optimum cutting parameters: depth of cut, cutting speed (Vc) and feed rate (f) that maintaining low flank wear (Vb). Taguchi method has been applied in this experiment. The Taguchi method has been universally used in engineering analysis. JMP statistical analysis software is used to analyse statically the development of flank wear rate during high speed milling of hardened steel AISI D2 to 60 HRD. The experiment was conducted in the following boundaries: cutting speed 200-400 m/min, feed rate of 0.01-0.05 mm/tooth and depth of cut of 0.1-0.2 mm. Analysis of variance ANOVA was conducted as one of important tool for statistical analysis. The result showed that cutting speed is the most influential input factors with 70.04% contribution on flank wear.

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Flume investigation of cylindrical baffles for dissipation of debris flow energy

10.5194/egusphere-egu21-14877 ◽

2021 ◽

Author(s):

Chan-Young Yune ◽

Beom-Jun Kim

Keyword(s):

Energy Dissipation ◽

Debris Flow ◽

Debris Flows ◽

High Speed ◽

Flow Characteristics ◽

Digital Camera ◽

Major Effect ◽

Small Scale ◽

Design Guideline ◽

Flow Energy

<p>A debris flow with a high speed along valleys has been reported to cause serious damages to urban area or infrastructure. To prevent debris flow disaster, countermeasures for flow-impeding structures are installed on the flow path of debris flows. Recently, an installation of cylindrical baffles which are open-type countermeasures has increased because of a low construction cost, filtering out rocks, and an increased hydraulic continuity. However, a comprehensive design guideline for specification and arrangement on cylindrical baffles has not yet been suggested. Moreover, the design of baffle installation is mainly based on empirical approaches as the influence of baffle array on debris mobility is not well understood. In this study, to investigate the effect of cylindrical baffles on the flow characteristics of debris flow, a series of small-scale flume tests were performed according to the varying baffle height and row numbers of installed baffles. High-speed cameras and digital camera to record the flow interaction with baffles were installed at the top and side of the channel. To reproduce the viscosity of debris flows caused by fine-grained soil in the flume, glycerin was mixed with debris materials (sand and gravel). After the test, the velocity and energy dissipation according to various baffle arrays were estimated. Test results showed that the installation of baffles reduced the frontal velocity of debris flows. Furthermore, taller baffles also increased the effect of the energy dissipation in debris flows, but additional rows of the baffle did not have a major effect on the energy dissipation. Thus, increasing the height of baffle led to an increased efficiency of energy dissipation of debris flows.</p>

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Implementation of experimental design methodology in preparation and characterization of zolmitriptan loaded chitosan nanoparticles

International Current Pharmaceutical Journal ◽

10.3329/icpj.v6i3.32684 ◽

2017 ◽

Vol 6 (3) ◽

pp. 16-22 ◽

Cited By ~ 2

Author(s):

Satish K. Mandlik ◽

Nisharani S. Ranpise

Keyword(s):

Statistical Analysis ◽

Factorial Design ◽

High Speed ◽

Chitosan Nanoparticles ◽

Spherical Shape ◽

Entrapment Efficiency ◽

Pharmaceutical Journal ◽

Optimization Method ◽

Fickian Diffusion ◽

Contour Plots

The present study investigated the implementation of 32 factorial design of experiment and statistical analysis for the optimization of chitosan nanoparticles containing zolmitriptan an antimigraine drug. The influence of chitosan concentration (X1) and sodium tripoly phosphate (X2) on responses namely nanoparticle size (Y1), and entrapment efficiency (Y2), was studied. As per design, nine runs of nanoparticles were prepared by modified ionic gelation method using high speed vortex mixing. The particle size was found in the range of 151-880 nm and entrapment efficiency was 72.3-81.2%. A statistical analysis was performed using licensed design expert software V.8.0 with respect to ANOVA, regression analysis. The contour plots and response surface plots showed visual representation of relationship between the experimental responses and the set of independent variables. Regression model equations were validated by a numerical and graphical optimization method. Further, optimized drug loaded nanoparticles showed +23.7mV zeta potential indicating storage stability, electron micrograph reflects spherical shape and mixed type of drug release followed by Fickian diffusion (n=0.266) was observed. Thus, using systematic factorial design approach, desirable goals can be achieved in shortest possible time with lesser number of experiments which was proven to be an effective tool in quality by design.Mandlik and Ranpise, International Current Pharmaceutical Journal, February 2017, 6(3): 16-22http://www.icpjonline.com/documents/Vol6Issue3/01.pdf

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Influence of Drilling Technique on the Radiographic, Thermographic, and Geomorphometric Effects of Dental Implant Drills and Osteotomy Site Preparations

Journal of Clinical Medicine ◽

10.3390/jcm9113631 ◽

2020 ◽

Vol 9 (11) ◽

pp. 3631

Author(s):

Lara Fraguas de San José ◽

Filippo Maria Ruggeri ◽

Roberta Rucco ◽

Álvaro Zubizarreta-Macho ◽

Jorge Alonso Pérez-Barquero ◽

...

Keyword(s):

Computed Tomography ◽

Dental Implant ◽

High Speed ◽

Digital Camera ◽

Study Groups ◽

Site Preparation ◽

Osteotomy Site ◽

Study Group ◽

Micro Computed Tomography ◽

Drilling Technique

The aim of this comparative study is to analyze the influence of drilling technique on the radiographic, thermographic, and geomorphometric effects of dental implant drills and osteotomy site preparations. One hundred and twenty osteotomy site preparations were performed on sixty epoxy resin samples using three unused dental implant drill systems and four drilling techniques performed with a random distribution into the following study groups: Group A: drilling technique performed at 800 rpm with irrigation (n = 30); Group B: drilling technique performed at 45 rpm without irrigation (n = 30); Group C: drilling technique performed at 45 rpm with irrigation (n = 30); and Group D: drilling technique performed at 800 rpm without irrigation (n = 30). The osteotomy site preparation morphologies performed by the 4.1 mm diameter dental implant drills from each study group were analyzed and compared using a cone beam computed tomography (CBCT) scan. The termographic effects generated by the 4.1 mm diameter dental implant drills from each study group were registered using a termographic digital camera and the unused and 4.1 mm diameter dental implant drills that were used 30 times from each study group were exposed to a micro computed tomography (micro-CT) analysis to obtain a Standard Tessellation Language (STL) digital files that determined the wear comparison by geomorphometry. Statistically significant differences were observed between the thermographic and radiographic results of the study groups (p < 0.001). The effect of cooling significatively reduced the heat generation during osteotomy site preparation during high-speed drilling; furthermore, osteotomy site preparation was not affected by the wear of the dental implant drills after 30 uses, regardless of the drilling technique.

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Real-time Simultaneous DKG and 2D DKG Using High-speed Digital Camera

Journal of Voice ◽

10.1016/j.jvoice.2016.08.005 ◽

2017 ◽

Vol 31 (2) ◽

pp. 247.e1-247.e7 ◽

Cited By ~ 5

Author(s):

Duck-Hoon Kang ◽

Soo-Geun Wang ◽

Hee-June Park ◽

Jin-Choon Lee ◽

Gye-Rok Jeon ◽

...

Keyword(s):

Real Time ◽

High Speed ◽

Digital Camera

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Design and Fabrication of a Micropump With Mixing Function for LOC

Journal of Medical Devices ◽

10.1115/1.2934349 ◽

2008 ◽

Vol 2 (2) ◽

Author(s):

Ho-jin Kang ◽

Bum-kyoo Choi

Keyword(s):

Lorentz Force ◽

High Speed ◽

Low Voltage ◽

Flow Direction ◽

Ionic Current ◽

Digital Camera ◽

Working Medium ◽

Electrode Length ◽

Portable System ◽

Phosphate Buffered Saline

A micropump, which includes a mixing function, has been fabricated. For the application to LOC (Lab On a chip), the micropump utilized PBS (Phosphate Buffered Saline) solution as the working medium. The solution is commonly used in biochemistry and cell culturing. The portable system and low energy consumption are important to realize the LOC device. In spite of a low voltage of 4V, the flow rate of the micropump was 0.02466ml∕min. The new micropump shows more enhanced performance than existing micropumps. The micropump uses Lorentz force actuation. The Lorentz force acting onto the ionic current in the PBS solution generates the fluid flow in the micropump. For the accurate prediction on flow direction, a computer simulation has been made using commercial CFD code. The results of simulation showing circulation direction were verified by experiment. The fluid circulation from each electrode combined and acted as the mixer in the micropump. The micropump was fabricated 20.2mm in length, 1mm in width and 400 μm in electrode length. To measure accurately, a high speed digital camera was used.

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Effect of Mechanical Vibration on Heat Transfer Characteristics of Liquid Film in Rectangular Microgrooves

ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels ◽

10.1115/icnmm2015-48294 ◽

2015 ◽

Author(s):

Chaohong Guo ◽

Dong Yu ◽

Xuegong Hu ◽

Yuyan Jiang ◽

Tao Wang ◽

...

Keyword(s):

Heat Transfer ◽

Liquid Film ◽

Heat Load ◽

High Speed ◽

Mechanical Vibration ◽

Digital Camera ◽

Vibration Frequencies ◽

Heat Transfer Characteristics ◽

Back Wall ◽

Groove Surface

The effects of vertical mechanical vibration on the heat characteristics of liquid film in vertical rectangular microgrooves are observed. The vibration frequencies are 6Hz, 10Hz and 30Hz, respectively; the vibration amplitudes are in the range of 1.95∼3.23mm. Three sizes of rectangular microgrooved plate are used in experiments. The microgrooved plate is vertically mounted on a vibration plane; DC heat load is added on the back wall of the microgrooved plate. Vibration of the liquid film in the microgroove is observed by a high-speed digital camera, and temperature on the back of the plate is recorded by a data acquisition. The experimental results show that temperature on the plate back decreases obviously with the increase of the vibration frequency or amplitude, heat transfer of the microgrooved plate is intensively enhanced. The main reason is that the forced convections on the groove surface and in the liquid film, caused by the mechanical vibration, enhance the heat transfer. The investigation provides more information for the application of the micro-configuration heat sink under fierce vibration conditions.

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THE HIGH-SPEED MILITARY TRACKED VEHICLE MAINTENACE SYSTEM - MODIFICATION IS NEEDED

Scientific Journal of the Military University of Land Forces ◽

10.5604/01.3001.0002.2736 ◽

2010 ◽

Vol 158 (4) ◽

pp. 71-83

Author(s):

Adam DRYHUSZ ◽

Kazimierz KOWALSKI

Keyword(s):

Statistical Analysis ◽

Management System ◽

High Speed ◽

Maintenance Management ◽

Tracked Vehicle ◽

Tracked Vehicles ◽

Maintenance Activity ◽

Maintenance System ◽

Original Interpretation

The maintenance system of high-speed military tracked vehicles and the graphic original interpretation of maintenance activity (mainly maintenance) are described. A modification of the maintenance system of the above-mentioned vehicles based on dependability-oriented maintenance (Reliability Cantered Maintenance – RCM) is proposed. Additionally, the use of the statistical analysis of maintenance cases and the development of Computerised Maintenance Management System – CMMC are proposed as well.

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