Assessment of Pantograph Loss-of-Contact Transients: A Follow-Up

2017 ◽  
Author(s):  
Bih-Yuan Ku ◽  
Guan-Ru Chen
Keyword(s):  
Field Test ◽  
Measurement Data ◽  
Field Tests ◽  
Performance Criteria ◽  
Effective Measure ◽  
Contact Wire ◽  
Video Clips ◽  
Loss Of Contact ◽  
European Standards

In this paper we present the follow-up of our work on the assessment of pantograph arcs during loss-of-contact transients. It is not easy to accurately detect the gap between the contact strip of the pantograph and the contact wire on the fly. Instead, in the European Standards EN50119 the measurable arcs are used in the performance criteria. This paper addresses the issue of arc detection from two aspects: arc image and arc intensity. Using the arc intensity sensors and an action camera we performed two field tests to verify the speculation that arc intensity does vary in different directions. This implies the requirement of more than one sensor in the detection of arcs, and the need to combine the outputs of all sensors to obtain an effective measure of arc intensity. Both issues are addressed in this paper using video clips and measurement data conducted in a field test in Taiwan.

Early Age Performance of Continuously Reinforced Concrete Pavement with Different Types of Aggregate

1997 ◽  
Vol 1568 (1) ◽  
pp. 35-43
Author(s):  
Yoon-Ho Cho ◽  
Terry Dossey ◽  
B. Frank Mccullough
Keyword(s):  
Reinforced Concrete ◽  
Field Test ◽  
Field Tests ◽  
Concrete Pavement ◽  
Crack Spacing ◽  
Winter Period ◽  
Thermal Coefficient ◽  
Curing Methods ◽  
Pavement Construction ◽  
New Variables

The effect of coarse aggregate on pavement performance has been attributed to the volume of aggregate used in pavement construction. The different patterns of crack development for limestone (LS) and siliceous river gravel (SRG) are a typical example of aggregate-induced variable performance in continuously reinforced concrete pavement (CRCP). An attempt was made to find a reasonable solution for pavements with SRG. As a way to solve the performance problem observed from the SRG pavement, a blended aggregates mixture was suggested. Laboratory and field tests were performed to check the feasibility of their application in pavements. From the laboratory test, a 50:50 blending ratio was suggested after considering the effect on tensile strength and thermal coefficient of expansion. Field test sections were also constructed to verify previous performance observations for the two aggregates and to provide performance data for new variables such as blended aggregates and special curing methods. Unexpectedly, the blended mixture did not improve the performance of SRG pavement; rather it experienced worse cracking than SRG alone. A controlled experiment with additional field test sections is needed to verify or disprove this finding. The only definitive finding was that selection of aggregate in the concrete pavement is a vital consideration for the design of the pavement. The CRCP8 analytical program reasonably predicted crack spacing for both SRG and LS pavements, predicting mean crack spacing of 0.99 m (3.25 ft) for SRG and 1.98 m (6.41 ft) for the limestone. These values are somewhat below the actual spacing observed at 100 days. Data collected after the first winter period will be required to calibrate the program.

Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas

2014 ◽  
Vol 70 (7) ◽  
pp. 1285-1291 ◽  
Author(s):  
Jia-jia Deng ◽  
Liang-ming Pan ◽  
De-qi Chen ◽  
Yu-quan Dong ◽  
Cheng-mu Wang ◽  
...  
Keyword(s):  
Field Test ◽  
Flue Gas ◽  
Cfd Simulation ◽  
Electrostatic Precipitator ◽  
Negative Impact ◽  
Positive Impact ◽  
Field Tests ◽  
Gas Temperature ◽  
Simulation Results ◽  
Desulfurization Wastewater

Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

scholarly journals Estimation of Outdoor PM2.5 Infiltration into Multifamily Homes Depending on Building Characteristics Using Regression Models

2021 ◽  
Vol 13 (10) ◽  
pp. 5708
Author(s):  
Bo-Ram Park ◽  
Ye-Seul Eom ◽  
Dong-Hee Choi ◽  
Dong-Hwa Kang
Keyword(s):  
Regression Analysis ◽  
Correlation Analysis ◽  
Field Test ◽  
Outer Surface ◽  
Regression Models ◽  
Field Tests ◽  
Test Results ◽  
Correlation And Regression Analysis ◽  
Building Characteristics ◽  
Pm2.5 Concentration

The purpose of this study was to evaluate outdoor PM2.5 infiltration into multifamily homes according to the building characteristics using regression models. Field test results from 23 multifamily homes were analyzed to investigate the infiltration factor and building characteristics including floor area, volume, outer surface area, building age, and airtightness. Correlation and regression analysis were then conducted to identify the building factor that is most strongly associated with the infiltration of outdoor PM2.5. The field tests revealed that the average PM2.5 infiltration factor was 0.71 (±0.19). The correlation analysis of the building characteristics and PM2.5 infiltration factor revealed that building airtightness metrics (ACH50, ELA/FA, and NL) had a statistically significant (p < 0.05) positive correlation (r = 0.70, 0.69, and 0.68, respectively) with the infiltration factor. Following the correlation analysis, a regression model for predicting PM2.5 infiltration based on the ACH50 airtightness index was proposed. The study confirmed that the outdoor-origin PM2.5 concentration in highly leaky units could be up to 1.59 times higher than that in airtight units.

scholarly journals Arteriovenous Passage Times and Visual Field Progression in Normal Tension Glaucoma

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Eva Charlotte Koch ◽  
Kay Oliver Arend ◽  
Marion Bienert ◽  
Andreas Remky ◽  
Niklas Plange
Keyword(s):  
Visual Field ◽  
Field Tests ◽  
Normal Tension Glaucoma ◽  
Retinal Blood Flow ◽  
Visual Field Progression ◽  
Confocal Scanning Laser Ophthalmoscope ◽  
Confocal Scanning ◽  
Confocal Scanning Laser ◽  
Passage Times

Purpose. Fluorescein angiographic studies revealed prolonged arteriovenous passage (AVP) times and increased fluorescein filling defects in normal tension glaucoma (NTG) compared to healthy controls. The purpose of this study was to correlate baseline AVP and fluorescein filling defects with visual field progression in patients with NTG.Patients and Methods. Patients with a follow-up period of at least 3 years and at least 4 visual field examinations were included in this retrospective study. Fluorescein angiography was performed at baseline using a confocal scanning laser ophthalmoscope (SLO, Rodenstock Instr.); fluorescein filling defects and AVP were measured by digital image analysis and dye dilution curves (25 Hz). Visual field progression was evaluated using regression analysis of the MD (Humphrey-Zeiss, SITA-24-2, MD progression per year (dB/year)). 72 patients with NTG were included, 44 patients in study 1 (fluorescein filling defects) and 28 patients in study 2 (AVP).Results. In study 1 (mean follow-up years, visual field tests), MD progression per year ( dB/year) was significantly correlated to the age (, ) but not to fluorescein filling defects, IOP, or MD at baseline. In study 2 (mean follow-up years, visual field tests), MD progression per year ( dB/year) was significantly correlated to AVP (, ) but not to age, IOP, or MD at baseline.Conclusion. Longer AVP times at baseline are correlated to visual field progression in NTG. Impaired retinal blood flow seems to be an important factor for glaucoma progression.

scholarly journals Early Childhood Practitioner Judgments of the Social Validity of Performance Checklists and Parent Practice Guides

2017 ◽  
Vol 5 (3) ◽  
pp. 176 ◽  
Author(s):  
Carl J. Dunst
Keyword(s):  
Early Childhood ◽  
Field Test ◽  
Social Validity ◽  
Field Tests ◽  
Intervention Programs ◽  
Early Childhood Intervention ◽  
The Social ◽  
Childhood Intervention ◽  
Made In

Findings from three field tests evaluations of early childhood intervention practitioner performance checklists and three parent practice guides are reported. Forty-two practitioners from three early childhood intervention programs reviewed the checklists and practice guides and made (1) social validity judgments of both products, (2) judgments of the compatibility of the checklists and practice guides, and (3) suggestions for improving the intervention products and materials. Results showed that practitioner feedback and suggestions yielded valuable information for improving the products where changes made in response to the practitioners’ social validity ratings and suggestions from the first field test had discernible effects on judgments and feedback of revised products. The importance of striving to develop intervention products and materials that are judged as socially important and acceptable is described.

The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction

2014 ◽  
Vol 39 (3) ◽  
pp. 232-237 ◽  
Author(s):  
Bryce Dyer
Keyword(s):  
Field Test ◽  
Aerodynamic Drag ◽  
Field Tests ◽  
Field Testing ◽  
Test Method ◽  
Limb Amputation ◽  
Small Scale ◽  
Prosthetic Limb ◽  
Testing Method ◽  
Competitive Cyclists

Background/Objectives: This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. Study design: The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. Methods: An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. Results: With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. Conclusion: A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Clinical relevance Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders’ equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible.

Abstract 16568: New Algorithms and Tailored Programming of Insertable Cardiac Monitors Reduce Alerts and Time Required to Follow Patients

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Kevin T Ousdigian ◽  
Sarah Rosemas ◽  
Jodi L Koehler ◽  
Ya-Jian Cheng ◽  
Esteban M Kloosterman
Keyword(s):  
Rapid Onset ◽  
Control Group ◽  
Full Time ◽  
Transmission Scheme ◽  
Review Time ◽  
Loss Of Contact ◽  
Full Time Employee ◽  
Time Required ◽  
New Algorithms

Introduction: Insertable Cardiac Monitors (ICM) aid in the diagnosis and monitoring of arrhythmias, however, reviewing the data is labor intensive and time consuming. Hypothesis: We hypothesized that new algorithms (ALG) and indication tailored programming (ITP) could reduce device-based alerts and clinician review time. Methods: Baseline data was obtained from a real-world de-identified Reveal LINQ TruRhythm ICMs database. The arrhythmia alerts and manual transmissions per patient/month was queried in this Control Group of patients with ≥3 months of follow-up. The effect of ALG and ITP was computed and applied to the Control Group. For practical purposes, the results were extrapolated to a 200 ICM clinic. Annualized clinic review time was estimated by assuming the staff time per transmission was 12.9 min., based on prior study. ALG improvements included: 1) Reject noise, loss of contact, and small R-waves for Pauses, 2) Require rapid onset for Tachy, 3) Limit nighttime episodes for Brady, and 4) Eliminate manual patient transmissions. ITP changes included: 1) Patients without Syncope: Pause ≥ 5 sec., Brady ≥ 12 beats and not during night, 2) Patients for AF Monitoring: AF ≥ 6 min. Results: The dataset consisted of 248,603 ICMs inserted for Syncope (36%), AF Diagnosis (35%), AF Monitoring (17%), and Other (12%) with an avg. of 1.1 years of follow-up (total 265,938 yrs). Applied to a 200 ICM clinic size, ALG and ITP reduced arrhythmia alerts by 32% (Control: 2,445 to ALG and ITP: 1,655 per clinic/yr). Using the new data transmission scheme eliminated 360 manual transmissions per clinic/yr.(Panel A) In total, the projected annual transmission volume (alerts + manuals in Panel A) and corresponding clinic review time (Panel B) dropped by 41% (247 hrs/yr = 13.1% full-time employee). Conclusion: Improved ALG and ITP can significantly reduce the volume of ICM alerts and consequently clinician review time impacting the management efficiency of this patient population.

“I'm Here for You”

2016 ◽  
pp. 55-75 ◽  
Author(s):  
Kelly R. Elander
Keyword(s):  
Online Learning ◽  
Video Clips ◽  
Instructor Presence ◽  
Historical Role ◽  
The Many

The author examines instructor presence by considering its historical role, the many important tasks that instruction presence accomplishes, and many ways instructional presence can be shown in online learning. Instructor presence has historically fulfilled four key functions: guidance, socialization, motivation, and coordination. Tasks that instructor presence can help with include welcoming and orienting learners, providing grades and explanations for grades, communicating course and instructor expectations and feedback on learner work, offering follow-up questions and comments, and moderating discussions. Seven techniques suggested to provide a sense of instructor presence include scheduling predetermined, regular appearances online, providing quick responses to comments and assignments, making occasional instructor posts throughout course discussions, offering periodic, brief, personal comments, providing special periods of instructor access, simulating presence by means of prerecorded audio or video clips and using instructor representatives.

scholarly journals 007 The outcome of a cohort of pregnancies in australian women with epilepsy

2019 ◽  
Vol 90 (e7) ◽  
pp. A3.1-A3
Author(s):  
Frank JE Vajda ◽  
Janet E Graham ◽  
Alison A Hitchcock ◽  
Cecilie M Lander ◽  
Terry J O’Brien ◽  
...  
Keyword(s):  
Retention Rate ◽  
Foetal Death ◽  
Telephone Interviews ◽  
Born Infant ◽  
Induced Abortions ◽  
Ethical Approval ◽  
Loss Of Contact ◽  
Major Illness ◽  
Foetal Malformations

BackgroundThe Australian Pregnancy Register (APR) established in 1998, collects data concerning the hazard of foetal malformations from intrauterine exposure to antiepileptic drugs.Methods4 telephone interviews, ethical approval, informed consent, observational study, statistical analyses.ResultsBy December 2017, the APR recorded 1879 pregnancies, followed prospectively. There had been 1766 live births (94.0%), 5 stillbirths (0.3%), 54 spontaneous abortions (2.9%), and 30 induced abortions (1.6%), while 24 pregnancies had an unknown outcome due to loss of contact with the women involved (1.3%). Foetal malformations had occurred in 71 of the live-born infants. Of the induced abortions, 15 had been for intrauterine foetal death, 10 for major foetal malformation (spina bifida, anencephaly and left heart underdevelopment), 2 for detected chromosome defects and 3 for maternal reasons (major illness in 2).By the end of the post-pregnancy year a further 99 pregnancies had become unavailable for follow-up (resulting in an 84.9% live-born infant final retention rate). An additional 33 pregnancies that had resulted in late recognised foetal malformations had been identified, nearly all in the first 6 months after birth. Intrauterine valproate exposure was involved in 447 of the 1731 antiepileptic drug treated pregnancies, a malformation-carrying pregnancy rate of 11.86%, as compared with a rate of 2.70% in the 148 drug-unexposed pregnancies (O.R. = 4.84; 95% C.I. 1.72, 13.62), used as comparators.ConclusionThis report confirms previous interpretations of the APR data, also providing insights into the pregnancies of women with epilepsy that did not result in live- born offspring.

scholarly journals Field Test Investigation of the Pile Jacking Performance for Prefabricated Square Rigid-Drainage Piles in Saturated Silt Sandy Soils

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Xiangying Wang
Keyword(s):  
Pore Water ◽  
Field Test ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Field Tests ◽  
Excess Pore Water Pressure ◽  
New Type ◽  
Test Investigation ◽  
First Time ◽  
Excess Pore

The rigid-drainage pile, designed to accelerate the dissipation of excess pore water pressure around the pile, is a new type of pile that combines the bearing capacity of ordinary rigid piles and the draining capacity of gravel piles. Field tests of these new piles were performed for the first time at a construction site in the new campus of Jiangyin No. 1 High School. Numerous parameters were observed for the test piles in many trials, including the excess pore water pressures, horizontal soil pressures, and displacements. At the measuring position at 0.6 m from the pile center, the rigid-drainage pile dissipates 70% of the peak excess pore water pressure in 1000 s, whereas the ordinary pile requires nearly 4000 s to dissipate the identical amplitude. The field test results clearly demonstrate that the rigid-drainage pile can reduce the amplitude of the peak pressure caused by piling in the liquefiable layer, quickly dissipate the excess pore water pressure, reduce the loss of effective stress in the soil surrounding the pile, and maintain the foundation stability.

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