Acoustic Emission (AE) Forecasting Rock Burst Key Technology

2013 ◽  
Vol 868 ◽  
pp. 314-318
Author(s):  
Guo Wei Dong
Keyword(s):  
Acoustic Emission ◽  
Propagation Distance ◽  
Wave Guide ◽  
Rock Surface ◽  
Quality Factors ◽  
Key Technology ◽  
Study Results ◽  
Actual Rock ◽  
Hole Bottom ◽  
Better Than

Acoustic emission (AE) technique is a trend of non-contact technique forecasting coal and rock dynamic disaster.Coal and rock AE propagation attenuation exponent function on different AE frequencies, different quality factors and different propagation distance are acquired by theory and numerical simulation and actual experiment; the effect of AE sensor installation manners on coal and rock surface , coal and rock bottom and wave guide are studied, the results show that the effect of AE sensor installation manner on wave guide is better than on coal and rock surface ,equivalent to installation manner on coal and rock hole bottom. Based on above study results, actual rock bursts are successfully forecasted.

scholarly journals The duration-energy-size enigma for acoustic emission

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Blai Casals ◽  
Karin A. Dahmen ◽  
Boyuan Gou ◽  
Spencer Rooke ◽  
Ekhard K. H. Salje
Keyword(s):  
Acoustic Emission ◽  
Mean Field Theory ◽  
Mean Field ◽  
Maximum Amplitude ◽  
Time Profile ◽  
Power Law Distribution ◽  
Model Predictions ◽  
Ae Signal ◽  
Strain Signal ◽  
Better Than

AbstractAcoustic emission (AE) measurements of avalanches in different systems, such as domain movements in ferroics or the collapse of voids in porous materials, cannot be compared with model predictions without a detailed analysis of the AE process. In particular, most AE experiments scale the avalanche energy E, maximum amplitude Amax and duration D as E ~ Amaxx and Amax ~ Dχ with x = 2 and a poorly defined power law distribution for the duration. In contrast, simple mean field theory (MFT) predicts that x = 3 and χ = 2. The disagreement is due to details of the AE measurements: the initial acoustic strain signal of an avalanche is modified by the propagation of the acoustic wave, which is then measured by the detector. We demonstrate, by simple model simulations, that typical avalanches follow the observed AE results with x = 2 and ‘half-moon’ shapes for the cross-correlation. Furthermore, the size S of an avalanche does not always scale as the square of the maximum AE avalanche amplitude Amax as predicted by MFT but scales linearly S ~ Amax. We propose that the AE rise time reflects the atomistic avalanche time profile better than the duration of the AE signal.

The Study on Color Quality Attributes of IMR with PET on White Ink by UV Inkjet

2014 ◽  
Vol 1004-1005 ◽  
pp. 799-802 ◽  
Author(s):  
Chang Lang Chen ◽  
Yu Tung Chang ◽  
Sheng Hao Taso ◽  
Weichieh Hsu
Keyword(s):  
Inkjet Printing ◽  
Screen Printing ◽  
Quality Attributes ◽  
Gravure Printing ◽  
Printing Process ◽  
Color Quality ◽  
Study Results ◽  
Color Differences ◽  
Pet Film ◽  
Better Than

The In-Mold Roller is a revolutionary printing process by which objects are 3D decorated. Products decorated by In-Mold Roller are waterproof and protected from fading. What’s more, these kinds of decorations strongly increase the beauty, desirability and value of the objects. The In-Mold Roller is now using either of gravure printing and screen printing to print PET film. However, there are some problems with these two techniques. This research is to investigate potential usages of combining In-Mold Roller with digital UV inkjet printing in 3D decoration, e.g. in personalized printing services. Study results found that when the coverage and the resolution of inkjet printing become higher, the SIDs will become higher as well. When transferred to ABS, SIDs in each combination will increase. Each combination of inkjet conditions, with the isolation of white ink, color differences are less variant. TVIs of white ink decrease 30% to 40% halftone and display in “M” type. In print contrast, C and K colors of each combination are better than M and Y colors. After transferred into print contrast, each combination of PC will be higher about 2 to5. When transferred to ABS, color variances of each combination are not huge, and color differences are about 3to5.

scholarly journals Differences in the Motor Coordination Abilities Among Adolescent Gymnasts, Swimmers, and Ice Hockey Players

2017 ◽  
Vol 18 (1) ◽  
Author(s):  
Timo Jaakkola ◽  
Anthony Watt ◽  
Sami Kalaja
Keyword(s):  
Motor Coordination ◽  
Ice Hockey ◽  
Specific Training ◽  
Young Athletes ◽  
Test Protocol ◽  
Male Adolescents ◽  
Age Related ◽  
Study Results ◽  
Hockey Players ◽  
Better Than

AbstractPurpose. Motor coordination is proposed to be a relatively stable age-related construct, unlikely to be influenced by aligned experiential factors such as intensive sport-specific training. The purpose of the study is to investigate if there are differences in motor coordination abilities among young artistic gymnasts, swimmers, and ice hockey players.Methods. The participants of the study were 508 female and 258 male adolescents (age, M = 12.80, SD = 1.10) comprising artistic gymnasts (n = 463), swimmers (n = 70), and ice hockey players (n = 233). The KTK-test protocol was used to analyse their gross motor coordination abilities.Results. The results of the study demonstrated that gymnasts scored better than ice hockey players and swimmers in the test of walking backwards along a beam, and better than ice hockey players in total motor coordination, hopping over an obstacle, and the test of moving sideways on wooden boards. However, ice hockey players scored higher than swimmers and gymnasts in the test of jumping from side to side. Subsequently, swimmers obtained better results in the test of moving sideways on wooden boards as compared with ice hockey players.Conclusions. The study results indicate that intensive sport-specific training may extend young athletes′ motor coordination characteristics in the ability areas representative of the sport in which they engage.

scholarly journals Analysis Of Usability In FIFA 15 and Pro Evolution Soccer (PES) 15 Using Mc Call’s Quality Factors

2016 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Yudistira Yudistira ◽  
Ahmad Subhan Yazid ◽  
Agung Fatwanto
Keyword(s):  
Quality Factor ◽  
Software Quality ◽  
Usability Testing ◽  
Quality Factors ◽  
User Interest ◽  
And Training ◽  
Better Than

FIFA 15 and Pro Evolution Soccer (PES) 15 are soccer games that are popular in Indonesia. Usability testing needs to be done to assess user interest and satisfaction with both and provide an overview of the comparison of them. The framework used for testing is McCall’S. The test combines operability matrix and training matrix to determine software quality. McCall’S was chosen because it has a reliable and comprehensive quality factor indicators. The results of the tests carried out were data on the operability level of PES15 games of 76.81% ± 15.76% and FIFA15 games of 70.65% ± 20.73%. Testing of training matrices produced 15.96 ± 21.74 seconds for PES15 and 78.29 ± 25.73 seconds for FIFA15 game training matrix. The data shows that reusability of PES15 is better than FIFA15.

scholarly journals Bayesian Uncertainty Estimation for Gaussian Graphical Models and Centrality Indices

2021 ◽  
Author(s):  
Joran Jongerling ◽  
Sacha Epskamp ◽  
Donald Ray Williams
Keyword(s):  
Bayesian Estimation ◽  
Graphical Models ◽  
Estimation Methods ◽  
Centrality Measures ◽  
Gaussian Graphical Models ◽  
Graphical Lasso ◽  
Study Results ◽  
Partial Correlations ◽  
Good Coverage ◽  
Better Than

Gaussian Graphical Models (GGMs) are often estimated using regularized estimation and the graphical LASSO (GLASSO). However, the GLASSO has difficulty estimating(uncertainty in) centrality indices of nodes. Regularized Bayesian estimation might provide a solution, as it is better suited to deal with bias in the sampling distribution ofcentrality indices. This study therefore compares estimation of GGMs with a Bayesian GLASSO- and a Horseshoe prior to estimation using the frequentist GLASSO in an extensive simulation study. Results showed that out of the two Bayesian estimation methods, the Bayesian GLASSO performed best. In addition, the Bayesian GLASSOperformed better than the frequentist GLASSO with respect to bias in edge weights, centrality measures, correlation between estimated and true partial correlations, andspecificity. With respect to sensitivity the frequentist GLASSO performs better.However, sensitivity of the Bayesian GLASSO is close to that of the frequentist GLASSO (except for the smallest N used in the simulations) and tends to be favored over the frequentist GLASSO in terms of F1. With respect to uncertainty in the centrality measures, the Bayesian GLASSO shows good coverage for strength andcloseness centrality. Uncertainty in betweenness centrality is estimated less well, and typically overestimated by the Bayesian GLASSO.

scholarly journals Comparison of retention of two proximal sealants in mandibular first molars of 12-year-old school children - A split-mouth randomized trial

2019 ◽  
Vol 1 ◽  
pp. 31-36
Author(s):  
Brinda Bhavani Sankar ◽  
Madan Kumar
Keyword(s):  
Randomized Trial ◽  
School Children ◽  
Public Health Service ◽  
United States Public Health ◽  
Adhesive System ◽  
Caries Risk ◽  
Color Match ◽  
Study Results ◽  
Left And Right ◽  
Better Than

Aim: This study was done to assess and compare the retention properties of a proximal sealant made of polyurethane dimethacrylate and a resin-based adhesive system for sealing proximal surfaces of permanent mandibular first molars in 12-year-old children over a period of 6 months. Methodology: A split-mouth randomized trial was conducted among 50 school children. Pre-operative and post-operative bitewing radiographs were taken bilaterally prior at baseline and the end of the sixth month. Separators were placed for those children who did not have physiological spacing. The interventions were delivered on the left and right sides after randomization as per the manufacturer’s instructions, and post-operative instructions were given to the participants. The interventions were assessed for retention primarily and other criteria such as color match, marginal discoloration, marginal adaptation, anatomic form, caries formation (using bitewing radiographs), post-operative sensitivity, and surface roughness at the end of the 1st, 3rd, and 6 months using United States Public Health Service Modified Ryge Criteria for Direct Clinical Evaluation of Restorations proposed by Cvar and Ryge, 1980. The data were compiled, analyzed using SPSS and results were generated. Conclusions: The study results revealed that the resin-based adhesive system was better than the adhesive patch in terms of retention over a period of 6 months. Hence, the feasibility of including proximal sealants as a part of the preventive regimen for caries risk children should be positively considered.

scholarly journals Numerical simulation and experimental research of cavitation nozzle based on equation curve

2021 ◽  
Author(s):  
Lifu Wang ◽  
Dongyan Shi ◽  
Zhixun Yang ◽  
Guangliang Li ◽  
Chunlong Ma ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Reynolds Number ◽  
Flow Field ◽  
High Speed ◽  
Quadratic Equation ◽  
Outer Contour ◽  
Study Results ◽  
Fluent Software ◽  
The Impact ◽  
Better Than

Abstract To further investigate and improve the cleaning ability of the cavitation nozzle, this paper proposes a new model that is based on the Helmholtz nozzle and with the quadratic equation curve as the outer contour of the cavitation chamber. First, the numerical simulation of the flow field in the nozzle chamber was conducted using FLUENT software to analyze and compare the impact of the curve parameters and Reynolds number on the cleaning effect. Next, the flow field was captured by a high-speed camera in order to study the cavitation cycle and evolution process. Then, experiments were performed to compare the cleaning effect of the new nozzle with that of the Helmholtz nozzle. The study results demonstrate that effective cavitation does not occur when the diameter of the cavitation chamber is too large. For the new nozzle, with the increase of the Reynolds number, the degree of cavitation in the chamber first increases and then decreases; the cleaning effect is much better than that of a traditional Helmholtz nozzle under the same conditions; the nozzle has the best cleaning effect for the stand-off distance of 300 mm.

Variation of regional seismic discriminants with surface topographic roughness in the Western United States

1996 ◽  
Vol 86 (3) ◽  
pp. 714-725 ◽  
Author(s):  
Tian-Run Zhang ◽  
Thorne Lay ◽  
Susan Schwartz ◽  
William R. Walter
Keyword(s):  
United States ◽  
Surface Roughness ◽  
Propagation Distance ◽  
Geographic Region ◽  
Western United States ◽  
Wave Guide ◽  
Spectral Ratios ◽  
Topographic Roughness ◽  
Individual Phase ◽  
Distance Dependence

Abstract Regional distance P and S waves behave differently with propagation distance due to complex elastic and anelastic effects in the crustal wave guide and uppermost mantle. It is well recognized that seismological discriminants based on P/S ratios or individual phase spectral ratios must be corrected for regionally dependent path effects for successful discrimination to be achieved. Such corrections usually involve only distance-dependent decay, parameterized to account for geometric spreading and attenuation factors averaged over some geographic region. However, large scatter persists in distance-corrected discriminants, which degrades their performance, and strategies are needed to further reduce the scatter by accounting for individual path variability. We demonstrate that characterizing some of the path variability by the readily measured surface topographic roughness along each path allows reduction of the scatter in some regional discriminants. Pg/Lg and Pn/Lg ratios and Pg, Pn, and Lg low-frequency/high-frequency spectral ratios for 80 earthquakes in the Western United States recorded at four stations of the Livermore NTS Network are analyzed for path effects. While all of these discriminants display distance dependence, log Pg/Lg is also found to be significantly correlated with average surface roughness along each path. The correlation is emphasized when the product of distance and roughness is used as an independent variable, and the data in the frequency range 1 to 6 Hz have the strongest trends. Corrections based on the correlations with distance and roughness can reduce the variance of the log Pg/Lg discriminant by 22 to 25% in the 2- to 4-Hz band. Log Pn/Lg and individual phase spectral ratios have stronger distance dependence than log Pg/Lg, but the correlation with surface roughness is weak for those measurements. It appears that interchange of Pg and Lg energy that reverberates in the crust accounts for the sensitivity to the gross wave-guide properties that are manifested in the surface roughness parameterization. The results support the concept of pursuing path corrections beyond purely range-dependent trends.

scholarly journals Consumer Needs for Hand-Touch Product Designs Based on the Experience Economy

2019 ◽  
Vol 11 (7) ◽  
pp. 2064 ◽  
Author(s):  
Jui-Che Tu ◽  
Cheng-Hsueh Yang
Keyword(s):  
Product Life Cycle ◽  
Economic Value ◽  
Sensory Stimulation ◽  
Purchase Decisions ◽  
Quality Factors ◽  
Experience Economy ◽  
The Sustainable Development ◽  
Study Results ◽  
Tactile Sensations ◽  
Insight Into

Hand-touch products are products that emphasize tactile sensations. These products can generate sensory stimulation and create memorable experiences for consumers, thereby driving purchase decisions. The economic value of hand-touch products is undoubtedly associated with the experience economy. Consumers generally focus on how much experience value is created by the hand-touch product itself. This study adopted the experience economy perspective to investigate the development of hand-touch products. To gain further insight into consumers’ product needs and place the focus of product development on the most important aspects, this study primarily adopted a questionnaire survey and Kano’s two-dimensional model to classify quality factors. In addition, the relative majority method was used to classify quality factors into five major categories: Attractive quality, One-dimensional quality, Must-be quality, Indifferent quality, Reverse quality. The study results showed that: (1) Consumers valued the sense marketing of hand-touch products. (2) Timely use of other marketing approaches enables a product to effectively meet customers’ needs. (3) Use of Cross Analysis to Identify Top-Priority Factors. This study’s findings on the true needs of consumers for hand-touch products can enhance and improve product life cycle, thereby achieving the sustainable development of products.

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