Field performance of a peat railway subgrade reinforced with helical screw piles

2018 ◽  
Vol 55 (12) ◽  
pp. 1888-1899 ◽  
Author(s):  
Lisa N. Wheeler ◽  
Michael T. Hendry ◽  
W. Andy Take ◽  
Neil A. Hoult
Keyword(s):  
High Speed ◽  
Field Performance ◽  
Strain Gauges ◽  
Field Site ◽  
Seasonal Fluctuations ◽  
Pile Installation ◽  
Significant Difference ◽  
Before And After ◽  
Ground Stabilization ◽  
Train Loading

Rail tracks on peat subgrades can experience significant deflections, some of which have led to derailments. A potential ground stabilization strategy is to use screw piles to reduce rail displacements; however, limited research has been undertaken to investigate the effect of these piles and their performance under cyclic train loading. A field site was instrumented and monitored before and after screw pile installation. The piles were instrumented with strain gauges, piezometers were installed in the peat, and high-speed cameras were used to measure track and subgrade displacements. The load carried by each instrumented pile was approximately 50–60 kN 3 weeks after installation, but reduced to approximately 30 kN after 6 months. Although 1 year’s worth of piezometric data were collected before installation of the piles, it is difficult to conclusively attribute the changes in pore pressures to the piles, particularly because the piezometric data collected after the pile installation were only available for the 7 months that exhibit the period of greatest seasonal fluctuations. The track support system deformations showed no significant difference pre- and post-pile installation. Therefore, based on the monitoring data at this site, it appears that the designed transfer of load from the ties to the piles through arching within the ballast layer was not realized.

scholarly journals Impact of cleaning regimes on dental water unit contamination

2011 ◽  
Vol 9 (4) ◽  
pp. 647-652 ◽  
Author(s):  
Soad A. Abdallah ◽  
Ahmed I. Khalil
Keyword(s):  
High Speed ◽  
Tap Water ◽  
Daily Basis ◽  
Dental Chair ◽  
Dental Clinics ◽  
Significant Difference ◽  
Before And After ◽  
Hand Piece ◽  
Viable Bacteria ◽  
Dental Unit Waterlines

Microorganisms that have been identified in dental unit waterlines (DUWLs) are of concern because they can cause infections, especially in immunocompromised patients. This study aimed to assess the incidence of microbial contamination in DUWLs before and after intervention to reduce contamination, and to investigate the presence of coliforms, Escherichia coli and Pseudomonas aeruginosa. Water samples were collected aseptically from the waterlines. The high-speed hand-piece and dental chair units were served by one distillation apparatus, which was fed by the potable tap water of four dental clinics. Different interventions were used: chlorination, flushing before clinics and between patients, draining at the end of the day, and freshly distilled water on a daily basis. There was a significant difference between the level of contamination in the high-speed hand-piece (1.5–2.7 log CFU/ml) and dental chair unit water (2.0–3.5 log CFU/ml). Coliforms (0.9%) E. coli (0.9%) and Pseudomonas (1.8%) were detected during 2008. This study indicates the need to monitor water quality regularly and prevent stagnation in DUWLs to reduce the number of viable bacteria to <100 CFU/ml. We recommend flushing the DUWL for 2 min before the first patient and for 10–20 s between patients, flushing the dental unit at the end of the day and draining it overnight to reduce the development of biofilms, and chlorination of the DUWLs.

scholarly journals ANDROID-BASED SPEED LIGHT IMPLEMENTATION TO INCREASE SAQ (SPEED, AGILITY AND QUICKNESS) AT U-16 FUTSAL ATHLETES AAFI LAGUE REGIONAL MEDAN

2021 ◽  
Vol 1 (2) ◽  
pp. 160-164
Author(s):  
Dody Yogaswara
Keyword(s):  
Time Series ◽  
Experimental Design ◽  
High Speed ◽  
Skill Level ◽  
Maximum Strength ◽  
Test Results ◽  
Series Design ◽  
Significant Difference ◽  
Before And After ◽  
Quasi Experimental

The purpose of this research is to produce speed, agility and quickness training which are progressive exercises that lead to the development of the main movement abilities to improve the ability of players or athletes so that they are better (faster) at their skills. Another opinion is that speed, agility and quickness are expected to increase the ability of athletes to use maximum strength during high-speed movements. The subjects in this study are futsal athletes U-16 of the AAFI Regional Medan league. The quasi-experimental design used is the time series design before the treatment of speed, agility and quickness (SAQ), from the initial tests conducted and obtained an SAQ level of 35.35135, then after being treated in the form of speed, agility and quickness (SAQ) with Android the athlete's skill level is 71.324324. So speed, agility and quickness (SAQ) are effective in improving the ability of AAFI Regional Medan athletes. Based on the results of the study it can be concluded that: (1) With speed, agility and quickness (SAQ) for AAFI Regional Medan athletes the evidence of this increase is shown in the test results of the pretest and posttest results of a significant difference between before and after the speed treatment , agility and quickness (SAQ) with Android.

scholarly journals Quantification of the Effect of Train Type on Concrete Sleeper Ballast Pressure Using a Support Condition Back-Calculator

2020 ◽  
Vol 6 ◽  
Author(s):  
Camila Pereira Silva ◽  
Marcus S. Dersch ◽  
J. Riley Edwards
Keyword(s):  
High Speed ◽  
Surface Strain ◽  
Rolling Stock ◽  
Strain Gauges ◽  
Analysis Tool ◽  
Field Site ◽  
Support Condition ◽  
Pressure Distributions ◽  
Wide Range ◽  
Support Conditions

Monitoring ballast support condition and improving current sub-structure and ballast maintenance strategies is critical to ensuring safe and efficient railroad operations. Researchers at the University of Illinois at Urbana-Champaign (Illinois) have developed a ballast support condition back-calculator, a non-destructive instrumentation method and corresponding analysis tool that quantifies ballast pressure distributions under concrete sleepers without interrupting revenue service train operations. This laboratory-validated non-intrusive method uses concrete sleeper bending moment profile and rail seat loads as inputs to back-calculate the reaction distribution using a Simulated Annealing optimization algorithm that incorporates Pareto Distribution as the random variable generator. In order to further understand in-service ballast support conditions, concrete surface strain gauges were installed on concrete sleepers at a revenue service field site to measure strains that could subsequently be converted into bending moments. This site is on a shared use rail corridor with traffic ranging from high speed passenger to heavy axle load (HAL) freight trains. Rail-mounted strain gauges were used to measure strains that were used to calculate the vertical wheel-rail loads to approximate rail seat loads. This paper quantifies the ballast pressure distributions beneath concrete sleepers under different types of rolling stock and evaluates how ballast support condition changes as a function of accumulated tonnage. A wide range of loads were observed at the field site, ranging from 4 to 35 kips (18–156 kN). Corresponding ballast pressures ranged from 14 to 175 psi (97–1,207 kPa), with sleeper-ballast contact area corresponding to 60% of the bottom of the sleeper area. The accumulation of 12.24 million gross tons (MGT) (12.44 million tons) did not generate a quantifiable change in ballast pressure values nor did it generate a change in the ballast support condition. The research results presented in this paper demonstrate the potential of the back-calculator to provide a stand-alone non-invasive method to quantify ballast support conditions, sleeper health, and sleeper bearing stress. Back calculator data will aid the rail industry in optimizing tamping cycles, enhancing safety, and developing more representative concrete sleeper flexural designs based on actual support conditions.

scholarly journals Effect of 9.3 μm CO2 and 2.94 μm Er:YAG Laser vs. Bur Preparations on Marginal Adaptation in Enamel and Dentin of Mixed Class V Cavities Restored With Different Restorative Systems

2021 ◽  
Vol 2 ◽  
Author(s):  
Clara Isabel Anton y Otero ◽  
Enrico Di Bella ◽  
Ivo Krejci ◽  
Tissiana Bortolotto
Keyword(s):  
Fatigue Test ◽  
High Speed ◽  
Er:Yag Laser ◽  
Marginal Adaptation ◽  
Class V ◽  
Significant Difference ◽  
Before And After ◽  
Universal Adhesives ◽  
Almost All ◽  
Post Hoc

This study aimed to compare marginal adaptation in enamel and dentin before and after aging of laser vs. bur-prepared mixed class V cavities restored by different restorative systems. Seventy two caries-free human molars were distributed to nine experimental groups; cavities were prepared using two different lasers: a handpiece -integrated 2.94 μm Er:YAG laser at 4.5 W, 300 mJ, and 0.75 W, 50 mJ with 15 Hz (LiteTouch, Light Instruments, Israel) and a novel CO2 laser at 12.95 W, 19.3 mJ, and 4.1 W, 6.11 mJ with 671 Hz (Solea 9.3 μm, Convergent Dental, USA). Cavities prepared with conventional diamond burs (Intensiv, Switzerland) in a red contra angle at high speed under maximal water cooling served as control. Cavities were prepared under simulation of dentinal fluid and restored using three different self-etching universal adhesives in combination with three nanohybrid composites, applied in two layers: Scotchbond Universal with Filtek Supreme XTE (3M, USA), G-Premio BOND with Essentia Universal (GC, Japan), and OptiBond Universal with Harmonize Universal (Kerr, USA). After restorations' polishing and simultaneous thermal (5–50°C, 2 min each) and mechanical loading (max. 49 N; 200,000 cycles), replicas of restoration margins were examined under SEM at × 200 magnification. Percentages of continuous margins (CMs) were quantified before and after the fatigue test and statistically compared (two-way ANOVA with Fisher's least significant difference [LSD] post hoc test). Significant differences were found in almost all groups between the results before and after the fatigue test, as well as between the different preparation tools and restorative materials (p < 0.05). Traditional bur preparations are confirmed as gold standard in enamel and dentin, as all three tested restorative systems provide results of marginal adaptation of more than 80% CM after loading. Er:YAG laser preparations can be equally effective in combination with SBU/Filtek Supreme XTE. CO2 laser ablation could not provide convincing results with the tested self-etching restorative systems. Marginal adaptation has been highly dependent on the substrate and showed impaired adhesion, especially in enamel. Scotchbond Universal/Filtek Supreme XTE showed the highest and most stable values of CM. The other two restorative systems were highly dependent on the preparation device of the substrate.

scholarly journals Ex VivoEvaluation of Secretion-Clearing Device in Reducing Airway Resistance within Endotracheal Tubes

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Christopher Waters ◽  
R. Constance Wiener ◽  
Hamed M. Motlagh
Keyword(s):  
Pressure Drop ◽  
Airway Resistance ◽  
Ex Vivo ◽  
Prolonged Mechanical Ventilation ◽  
Performance Testing ◽  
Field Performance ◽  
Primary Objective ◽  
Endotracheal Tubes ◽  
Significant Difference ◽  
Before And After

Background. Secretions accumulate in endotracheal tubes’ (ETT) lumens upon their placement in patients. The secretions impact airway resistance and pressure. Secretions potentiate prolonged mechanical ventilation and ventilator-associated pneumonia. Our primary objective in this study was to evaluate an ETT-clearing device (ETT-CD) in its ability to remove secretions fromex vivoETT lumens.Methods. Forty ETTs, obtained from intensive care patients at extubation, were individually placed into a ventilator field performance testing simulator at 37°C. The pressure drop through the ETTs was measured at a flow rate of 60 L/min before and after cleaning with the ETT-CD and compared with unused, similarly sized controls tubes. The ETT-CD was inserted into an ETT until the tip reached Murphy’s eye (hole in the side) of the ETT. The wiper, set back from the tip, was expanded by ETT-CD handle activation. As the ETT-CD was removed, the distal wiper extracted secretions from the ETT lumen.Results. Forty ETTs were tested with nonparametric Wilcoxon signed-rank tests. Before being cleared with the ETT-CD, the median pressure drop in the extubated 7.5 mm ETTs was 17.8 cm H2O; after ETT-CD use, it was 12.3. The cleared ETTs were significantly improved over the ETTs before being cleared (p<0.001); however, there remained a significant difference between the cleared ETTs and the control tubes (p=0.005), indicating the clearing was not to the level of an unused ETT. Similar results were determined for the 8.0 mm ETTs.Conclusions. For the 7.5 mm and the 8.0 mm EETs, the ETT-CD improved effective patency of the ETTs over the uncleared ETTs, independent of occlusion location, tube size, or length of tube. However, there remained a significant difference between the cleared tubes and controls.

Assessment of the Stress Transmitted to Dental Implants Connected to Screw-Retained Bars Using Different Casting Techniques

2014 ◽  
Vol 40 (6) ◽  
pp. 641-648 ◽  
Author(s):  
Klaus Haselhuhn ◽  
Juliana Marotti ◽  
Pedro Tortamano ◽  
Claudia Weiss ◽  
Lubna Suleiman ◽  
...  
Keyword(s):  
Computer Software ◽  
Strain Gauges ◽  
Implant Position ◽  
Casting Technique ◽  
Distortion Analysis ◽  
Significant Difference ◽  
Before And After ◽  
Passive Fit ◽  
Master Model ◽  
Data Acquisition And Processing

Passive fit of the prosthetic superstructure is important to avoid complications; however, evaluation of passive fit is not possible using conventional procedures. Thus, the aim of this study was to check and locate mechanical stress in bar restorations fabricated using two casting techniques. Fifteen patients received four implants in the interforaminal region of the mandible, and a bar was fabricated using either the cast-on abutment or lost-wax casting technique. The fit accuracy was checked according to the Sheffield's test criteria. Measurements were recorded on the master model with a gap-free, passive fit using foil strain gauges both before and after tightening the prosthetic screws. Data acquisition and processing was analyzed with computer software and submitted to statistical analysis (ANOVA). The greatest axial distortion was at position 42 with the cast-on abutment technique, with a mean distortion of 450 μm/m. The lowest axial distortion occurred at position 44 with the lost-wax casting technique, with a mean distortion of 100 μm/m. The minimal differences between the means of axial distortion do not indicate any significant differences between the techniques (P = 0.2076). Analysis of the sensor axial distortion in relation to the implant position produced a significant difference (P &lt; 0.0001). Significantly higher measurements were recorded in the axial distortion analysis of the distal sensors of implants at the 34 and 44 regions than on the mesial positions at the 32 and 42 regions (P = 0.0481). The measuring technique recorded axial distortion in the implant-supported superstructures. Distortions were present at both casting techniques, with no significant difference between the sides.

scholarly journals Comparison of Interproximal Reduction Techniques and Proximal Strips: An Atomic Force Microscopic and Confocal Microscopic Study

2020 ◽  
Vol 54 (1) ◽  
pp. 44-48
Author(s):  
Pooja Harish S ◽  
Karunakara B C ◽  
Sumitra Reddy
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscope ◽  
High Speed ◽  
Reduction Technique ◽  
Tooth Surface ◽  
Control Group ◽  
Reduction Techniques ◽  
Atomic Force ◽  
Significant Difference ◽  
Before And After

Objective: A vivo study was conducted to evaluate the surface roughness produced by two different methods: hand-held mechanical and air-rotor stripping and also by HORICO and Ortho-Organizer strips (Bengaluru, India), before and after polishing with 3M Sof-Lex Finishing Strips under Atomic Force Microscope. Methodology: Study included 44 proximal surfaces of extracted premolars divided into a control group and 3 experimental groups with 12 surfaces in each. Hand-held mechanical stripping was done by 40 passages of 6 cm long abrasive strips and air-rotor stripping using high-speed air-rotor turbine hand piece. Polishing was done using 3M Sof-Lex finishing strips. Reduced teeth samples were viewed under Atomic Force Microscope and the proximal strips under Confocal microscope for surface roughness. Results: Air-rotor stripping produced statistically significant more surface roughness compared to the mechanical reduction technique ( P = .01). There was no significant difference between the roughnesses produced by 2 different proximal strips. Tooth surface after IPR with polishing had less roughness compared to unpolished surface. There was no mean difference between the wear of proximal strips. Conclusion: The mechanical reduction technique of interproximal surface produces less surface roughness compared to air-rotor stripping. Polishing with 3M Sof-Lex strips after reduction irrespective of the technique and material used gives smoother surface than even normal enamel.

scholarly journals Evaluation of the Super League Team’s Competition Analysis before and after the COVID-19 Outbreak Is Given

2021 ◽  
Vol 7 (1) ◽  
pp. 45
Author(s):  
M. Onur Sever ◽  
Ömer Zambak
Keyword(s):  
High Intensity ◽  
High Speed ◽  
Football Players ◽  
Competition Analysis ◽  
Average Speed ◽  
Total Distance ◽  
Significant Difference ◽  
Before And After ◽  
Paired T Test ◽  
Super League

The paper is aimed to determine whether there is a loss of performance by comparing the competition values of the Super League team before and after the COVID-19 epidemic. In order to reduce the performance losses of the athletes due to lack of training, 60-75 minutes of self-weight training was applied during the quarantine period. Paired t test was used for statistical analysis. A statistically significant difference was found in the Total Distance, High Intensity Distance, Sprint Distance, High Speed Distance, Number of High Intensity Runs, Number of Sprints, Number of High Speed Runs, Average Speed, Total Distance in Possession, Total Distance Out of Possession, Total Distance Ball Out of Play, High Intensity Distance in Possession, High Intensity Distance Out of Possession, High Intensity Distance Ball Out of Play, Sprint in Possession, Sprint Out of Possession, Sprint Ball Out of Play, High Speed Distance in Possession, High Speed Distance Out of Possession, High Speed Distance Ball Out of Play values of the athletes compared to p < 0.05. As a result, it has been observed that the training of super league football players with their own body weight during the quarantine period positively affects their performance during the season.

The influence of osteopathic correction on the rate of various rhythms of the body

2019 ◽  
pp. 64-71 ◽  
Author(s):  
A. E. Chernikova ◽  
Yu. P. Potekhina
Keyword(s):  
Heart Rate ◽  
Respiratory Rate ◽  
Age Groups ◽  
Biomechanical Properties ◽  
Dispersion Analysis ◽  
The Body ◽  
Body Tissues ◽  
Age Related ◽  
Significant Difference ◽  
Before And After

Introduction. An osteopathic examination determines the rate, the amplitude and the strength of the main rhythms (cardiac, respiratory and cranial). However, there are relatively few studies in the available literature dedicated to the influence of osteopathic correction (OC) on the characteristics of these rhythms.Goal of research — to study the influence of OC on the rate characteristics of various rhythms of the human body.Materials and methods. 88 adult osteopathic patients aged from 18 to 81 years were examined, among them 30 men and 58 women. All patients received general osteopathic examination. The rate of the cranial rhythm (RCR), respiratory rate (RR) heart rate (HR), the mobility of the nervous processes (MNP) and the connective tissue mobility (CTM) were assessed before and after the OC session.Results. Since age varied greatly in the examined group, a correlation analysis of age-related changes of the assessed rhythms was carried out. Only the CTM correlated with age (r=–0,28; p<0,05) in a statistically significant way. The rank dispersion analysis of Kruskal–Wallis also showed statistically significant difference in this indicator in different age groups (p=0,043). With the increase of years, the CTM decreases gradually. After the OC, the CTM, increased in a statistically significant way (p<0,0001). The RCR varied from 5 to 12 cycles/min in the examined group, which corresponded to the norm. After the OC, the RCR has increased in a statistically significant way (p<0,0001), the MNP has also increased (p<0,0001). The initial heart rate in the subjects varied from 56 to 94 beats/min, and in 15 % it exceeded the norm. After the OC the heart rate corresponded to the norm in all patients. The heart rate and the respiratory rate significantly decreased after the OC (р<0,0001).Conclusion. The described biorhythm changes after the OC session may be indicative of the improvement of the nervous regulation, of the normalization of the autonomic balance, of the improvement of the biomechanical properties of body tissues and of the increase of their mobility. The assessed parameters can be measured quickly without any additional equipment and can be used in order to study the results of the OC.

Melatih Kepemimpinan Perangkat Desa Kebonharjo Kulonprogo: Membangun Sikap Anti Korupsi

2018 ◽  
Vol 1 ◽  
pp. 107
Author(s):  
Adi Heryadi ◽  
Evianawati Evianawati
Keyword(s):  
Transformational Leadership ◽  
Data Collection ◽  
Paired Samples ◽  
Significant Difference ◽  
Before And After ◽  
Post Test ◽  
Sample Test ◽  
Corruption Perception ◽  
Measuring Tool

This study aims to prove whether transformational leadership training is effective for building anti-corruption attitudes of villages in Kebonharjo village, subdistrict Samigaluh Kulonprogo. This research is an experimental research with one group pre and posttest design.Subject design is 17 people from village of 21 candidates registered. Measuring tool used in this research is the scale of anti-corruption perception made by the researcher referring to the 9 anti-corruption values with the value of reliability coefficient of 0.871. The module used as an intervention made by the researcher refers to the transformational leadership dimension (Bass, 1990). The data collected is analyzed by statistical analysis of different test Paired Sample Test. Initial data collection results obtained sign value of 0.770 which means> 0.05 or no significant difference between anti-corruption perception score between before and after training. After a period of less than 1 (one) month then conducted again the measurement of follow-up of the study subjects in the measurement again using the scale of anti-corruption perception. The results of the second data collection were analysed with Paired Samples Test and obtained the value of 0.623 sign meaning p> 0.05 or no significant difference between post test data with follow-up data so that the hypothesis of this study was rejected.

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