Vibration Compensation for a Vehicle-mounted Atom Gravimeter

The performance of the absolute atom gravimeters used on moving platforms, such as vehicles, ships and aircrafts, is strongly affected by the vibration noise. To suppress its influence, we summarize a vibration compensation method utilizing data measured by a classical accelerometer. The measurements with the accelerometer show that the vibration noise in the vehicle can be 2 order of magnitude greater than that in the lab during daytime, and can induce an interferometric phase fluctuation with a standard deviation of 16.70π. With the compensation method, our vehicle-mounted atom gravimeter can work normally in these harsh conditions. Comparing the Allan standard deviations before and after the vibration noise correction, we find a suppression factor of 22.74 can be achieved in static condition with an interrogation time of T = 20 ms, resulting a sensitivity of 1.35 mGal/Hz1/2, and a standard deviation of 0.5 mGal with an average time of 10 s. We also demonstrate the first test of an atom gravimeter in a moving vehicle, in which a suppression factor of 50.85 and a sensitivity of 60.88 mGal/Hz1/2 were realized with T = 5 ms.

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Effects and Prospects of the Vibration Isolation Methods for an Atomic Interference Gravimeter

Sensors ◽

10.3390/s22020583 ◽

2022 ◽

Vol 22 (2) ◽

pp. 583

Author(s):

Wenbin Gong ◽

An Li ◽

Chunfu Huang ◽

Hao Che ◽

Chengxu Feng ◽

...

Keyword(s):

Vibration Isolation ◽

Prospective Development ◽

Passive Vibration Isolation ◽

Isolation Methods ◽

Challenging Environment ◽

Research Findings ◽

Active Vibration ◽

Vibration Compensation ◽

Atomic Interference ◽

Vibration Noise

An atomic interference gravimeter (AIG) is of great value in underwater aided navigation, but one of the constraints on its accuracy is vibration noise. For this reason, technology must be developed for its vibration isolation. Up to now, three methods have mainly been employed to suppress the vibration noise of an AIG, including passive vibration isolation, active vibration isolation and vibration compensation. This paper presents a study on how vibration noise affects the measurement of an AIG, a review of the research findings regarding the reduction of its vibration, and the prospective development of vibration isolation technology for an AIG. Along with the development of small and movable AIGs, vibration isolation technology will be better adapted to the challenging environment and be strongly resistant to disturbance in the future.

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Organizational Development Towards Excellent Management

The Journal of Social Sciences Research ◽

10.32861/jssr.spi4.254.257 ◽

2018 ◽

pp. 254-257

Keyword(s):

Regression Analysis ◽

Standard Deviation ◽

Organizational Development ◽

Assessment Model ◽

Survey Method ◽

Significant Difference ◽

Before And After ◽

Level Of Knowledge ◽

And Behavior ◽

Percentage Standard Deviation

This study will use the Kirkpatrick Assessment Model to assess the School Excellence program through Organization Development (PrOD). This model involves evaluation of reactions, learning (knowledge, skills and attitude), behavior and outcomes, but this study only assesses knowledge and behavior . This study uses survey method by involving 120 respondents of the study chosen by group sampling. The instrument is a questionnaire that has Cronbach Alpha value between 0.930-0.984. The data were analyzed using mean score, percentage, standard deviation and regression. Analysis findings show that there is a significant difference between the level of knowledge and behavior before and after the PrOD. Overall, this study recommends PrOD to be continued, but it is necessary to improve in the formulation of PrOD syllabus so that school leaders can improve the behavior change in meaningful and meaningful implementation of the PrOD.

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The Effect of Aroma Therapy Olive Oil Massage to Pain Dysmenorrhea on Midwifery Level I and II Students at Tri Mandiri Sakti Institute of Health Sciences

Jurnal Sains Kesehatan ◽

10.37638/jsk.25.3.22-32 ◽

2018 ◽

Vol 25 (3) ◽

pp. 22-32

Author(s):

Tria Nopi Herdiani ◽

Mika Oktarina ◽

Yeni Nuraeni

Keyword(s):

Standard Deviation ◽

Olive Oil ◽

Sampling Technique ◽

Health Sciences ◽

Pain Scale ◽

Adolescent Women ◽

Before And After ◽

Post Test ◽

Average Pain ◽

Level I

Reproductive health problems are dysmenorrhea is a problem related with menstruation. research show the highest prevalence of menstrual pain in adolescent women, adolescent who experience dysmenorrhea report pain that interferes with daily activities. Handling to reduce pain during menstruation, one of which is using the olive oil aroma therapy aroma method. This research to determine the effect of aroma therapy olive oil massage pain dysmenorrhea on midwifery student level I and II Stikes Tri Mandiri Sakti Bengkulu.This study used a pre experiment in one group (one group pre-post test design) the dependent variable of pain before and after treatment. Sampling was done by accidental sampling technique using the criteria totaling 41 student who experience dysmenorrhea. The study was conducted from May to June 2017. Retrievel of data using the observatioan sheet and analyzed using compared mean paired T-test. The Result of the research: (1) At 41 people in the first and second grade obstetric students who had dysmenorrhea before the massive olive oil odor therapy aroma got the average pain scale 5,73 with the standard deviation 1,450. (2) In 41 subjects who had dysmenorrhea after the massage of olive oil odor therapy, the average pain scale was 5,00 with a standard deviation of 1,414. (3) There is massive effect of olive oil odor therapy to dysmenorrhea pain in female students of Level I and II Prodi DIII Midwifery Tri Mandiri Sakti Institute of Health Sciences Bengkulu. Keywords : aroma therapy, dysmenorrhea, massage

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Abstract 15240: Evaluation of the Performance and Safety of Wideband Cardiac MRI in Patients With a Cardiac Implantable Electronic Device (CIED)

Circulation ◽

10.1161/circ.142.suppl_3.15240 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Sarah M Schwartz ◽

Ashitha Pathrose ◽

Ali Serhal ◽

Ryan Avery ◽

Ann Ragin ◽

...

Keyword(s):

Image Quality ◽

Electronic Device ◽

Pulse Sequences ◽

Free Breathing ◽

Whole Body ◽

Breath Hold ◽

Single Shot ◽

Before And After ◽

Order Of Magnitude ◽

Chest X Ray

Introduction: Wideband late gadolinium enhancement (LGE) CMR is capable of suppressing image artifacts induced by cardiac implanted electronic devices (CIEDs). We implemented our own wideband segmented (seg) breath-hold and wideband single-shot (SS) free-breathing LGE pulse sequences and used them clinically since 2016. The purpose of this study was to evaluate image quality and CMR safety of wideband LGE compared to standard LGE. Methods: We retrospectively identified 54 consecutive patients (mean age: 61±15 years; 31% females) with CIED (33 t-ICD, 4 s-ICD, 15 pacemaker, 1 CRT-D, 1 CRT-P) who underwent CMR at 1.5T (Avanto, Siemens). Standard seg, wideband seg, and wideband SS LGE used standard imaging parameters. 16 myocardial segments were scored for scar/myocardial conspicuity and presence of any visual artifact on a 5-point Likert scale (1:worst; 3:acceptable; 5:best). Distance between center of the heart and CIED (CXR D) was measured on chest X-ray. Whole-body specific absorption rate (SAR) was read from DICOM metadata. Device changes were calculated from pre- and post- device interrogation measurements. Results: Both wideband seg and SS LGE consistently produced better image quality than standard LGE (Figure 1A). Median conspicuity and artifact scores were significantly better for wideband seg (F=20.6, p<0.001) and wideband SS (F=24.2, p<0.001) LGE compared to standard LGE. There was a trend in conspicuity and artifact scores with CIED distance for standard LGE (rho=0.476, p=0.02), but not wideband LGE scans (Figure 1B, 1C). Whole-body SAR averaged for both wideband scans (0.15±0.04 W/kg) was one order of magnitude below the 2.0 W/kg FDA limit. Device parameters (sensing, impedance, threshold, battery level) did not differ before and after CMR including wideband LGE. Conclusions: Both wideband seg and SS LGE scans produced improved image quality compared to standard LGE while maintaining CMR safety. *The first two authors (SS and AP) contributed equally

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Absence of sustained hypertension in sinoaortic-denervated rabbits

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1986.251.4.h742 ◽

1986 ◽

Vol 251 (4) ◽

pp. H742-H747 ◽

Cited By ~ 14

Author(s):

M. Saito ◽

N. Terui ◽

Y. Numao ◽

M. Kumada

Keyword(s):

Standard Deviation ◽

Arterial Pressure ◽

Critical Role ◽

Baroreceptor Reflex ◽

Sham Operation ◽

Indwelling Catheter ◽

Before And After ◽

Cervical Sympathetic ◽

Cervical Sympathetic Nerve

In 21 conscious unrestrained rabbits, arterial pressure was continuously recorded up to 11 wk by an indwelling catheter placed in the thoracic aorta. The average and standard deviation of the 24-h mean arterial pressure (MAP) were calculated and compared before and after sinoaortic denervation, sham operation, or cervical sympathectomy. At the time of sinoaortic denervation, the cervical sympathetic nerve was always disrupted bilaterally to remove possible arterial barosensory afferents contained in it. Subsequent to sinoaortic denervation performed on 12 rabbits, the average 24-h MAP was initially elevated but invariably returned to the predenervation level in 5-36 days (average 14 days). Meanwhile, the standard deviation remained elevated in all but one animal. In five sham-operated or four cervical-sympathectomized animals, neither the average 24-h MAP nor the standard deviation was significantly altered from that of controls. Our results are consistent with the view that the arterial baroreceptor reflex by itself does not play a critical role in determining the long-term level of arterial pressure.

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Vibration Compensation of the Frequency-Scanning-Interferometry-Based Absolute Ranging System

Applied Sciences ◽

10.3390/app9010147 ◽

2019 ◽

Vol 9 (1) ◽

pp. 147 ◽

Cited By ~ 1

Author(s):

Fu-Min Zhang ◽

Ya-Ting Li ◽

Hao Pan ◽

Chun-Zhao Shi ◽

Xing-Hua Qu

Keyword(s):

Standard Deviation ◽

Vibration Frequency ◽

Phase Modulation ◽

Vibration Velocity ◽

Sinusoidal Vibration ◽

Vibration Effect ◽

Frequency Scanning ◽

Blind Area ◽

Frequency Scanning Interferometry ◽

Vibration Compensation

The frequency-scanning-interferometry-based (FSI-based) absolute ranging technology is a type of ranging technology possessing a high precision and no ranging blind area, so it can be used for non-cooperative targets. However, due to a tiny movement of a target, the Doppler shift and the phase modulation are introduced into the beat signal which results in ranging accuracy decrease. In order to solve this problem, first the model of vibration effect is established, and then the beat signals of two adjacent scanning periods are processed to produce a signal that is immune to vibration. The proposed method is verified by the experiments, and the experimental results show that the effect of vibration compensation is better for the target with a lower vibration velocity and at a lower vibration frequency (lower than 6 Hz). When the target is subjected to a sinusoidal vibration with an amplitude of 10 μm at a frequency of 1 Hz, by using the proposed method the standard deviation is reduced from 775 to 12 μm. Moreover, in the natural environment, by using vibration compensation the standard deviation is reduced from 289 to 11 μm.

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Assessment and documentation of incontinence-associated dermatitis after implementation of a standardised instrument: a comparative study

Journal of Wound Care ◽

10.12968/jowc.2019.28.sup9.s4 ◽

2019 ◽

Vol 28 (Sup9) ◽

pp. S4-S11 ◽

Cited By ~ 1

Author(s):

Mary Montague ◽

Matthew Karafa ◽

Nancy M. Albert

Keyword(s):

Standard Deviation ◽

Weighted Kappa ◽

Severity Index ◽

Skin Condition ◽

Assessment Instrument ◽

Clinical Nurses ◽

Before And After ◽

Implementation Period ◽

Improved Accuracy ◽

Good Agreement

Objective: In this study, clinical nurses' documentation of incontinence-associated dermatitis (IAD) were compared with wound expert documentation before and after implementing a valid, reliable severity index (SI) instrument. Methods: A prospective, non-equivalent, two group comparative design within three hospital medical units. Pre- and post-implementation skin condition documentation were compared by clinician type, and post-implementation IADSI scores were assessed for agreement using standard and weighted Kappa. Results: Of 89 patients (pre-, n=48 and post-, n=38), mean (standard deviation) age was 72.4±13.7 years and 57.3% had IAD. Mean IADSI score was 13.2 (standard deviation: 10.5; range: 0–52), reflecting pink intact skin. Post-implementation, skin documentation between clinicians was more likely to match, from 35.4 to 84.2%, p<0.001. Post-implementation, after controlling for age, gender and race, the odds ration (OR) of matched documentation between clinicians was 5.80 ([95% confidence interval: 1.8, 18.6], p=0.003) compared with pre-implementation. In the post-implementation period, standard Kappas for agreement in clinical nurse-wound expert documentation in the lower back/buttocks/upper thigh areas ranged from 0.82 to 1.0, reflecting very good agreement. Weighted kappas ranged from 0.76 to 1.0, also reflecting good to very good agreement. Conclusion: Implementation of an IADSI assessment instrument improved accuracy of IAD documentation.

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Spotlight counts for assessing abundance of rabbits (Oryctolagus cuniculus L.)

Wildlife Research ◽

10.1071/wr97004 ◽

1999 ◽

Vol 26 (5) ◽

pp. 609 ◽

Cited By ~ 14

Author(s):

David J. Fletcher ◽

Henrik Moller ◽

B. Kay Clapperton

Keyword(s):

New Zealand ◽

Oryctolagus Cuniculus ◽

Heavy Rain ◽

Mackenzie Basin ◽

Large Numbers ◽

Before And After ◽

Order Of Magnitude ◽

Kill Rate ◽

Unexplained Variance ◽

New Zealand Rabbits

We determined the precision of spotlight counts of rabbits (Oryctolagus cuniculus L.) and their accuracy as estimates of density, by making counts from a motorcycle along 17 1-km transects in the Mackenzie Basin, New Zealand. Rabbits were poisoned and density per 1-ha quadrat was measured. Precision of spotlight counts would be between 5–28% and 6–39%, using impracticably large numbers of counts, even allowing for the effects of snow and heavy rain, observer bias and number of runs per night. Spatial and unexplained variance would result in even less precise counts using 25 transects and 1–5 nights. Actual rabbit densities explained only 41% of the variance in spotlight counts. Confidence intervals of absolute rabbit densities are extremely large, especially when observed counts are high. At best, spotlight counts could be used to detect differences in actual rabbit abundance spanning an order of magnitude or more. Observed reduction in spotlight counts is likely to underestimate reduction in actual density because the spotlight count index ‘saturates’ at high rabbit density. However, spotlight counts along fixed transects before and after a control operation can be used to estimate percentage kill with acceptable precision if the kill rate is at least 80%.

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A Vibration Compensation Method for Absolute Gravimeters

Volume 4B: Dynamics, Vibration, and Control ◽

10.1115/imece2016-66719 ◽

2016 ◽

Cited By ~ 1

Author(s):

Guan Wang ◽

Hua Hu ◽

Kang Wu ◽

Lijun Wang

Keyword(s):

Transfer Function ◽

Laser Interferometer ◽

Compensation Method ◽

Gravity Measurement ◽

Absolute Gravity ◽

Absolute Gravimeter ◽

Broadband Seismometer ◽

Vibration Isolators ◽

Vibration Compensation ◽

Absolute Gravity Measurement

The laser interferometer is used to track the falling object in a freefall absolute gravimeter, which could be disturbed by the vibration from the ground. Thus, the vibration compensation method is often used to reduce the influence of the vibration. Typically, a sensor (broadband seismometer) is used to record the vibration. But the measured ‘vibration’ Nm(t) does not equal the motion of the reference corner cube N(t). Because there exists a transfer function G(s) making Nm(s) = G(s)N(s). Traditionally, G(s) is assumed to be equal to the transfer function of the sensor, which can be achieved with the help of other equipment. But the assumption is not reasonable and the process of calculating the transfer function is complicated. A novel vibration compensation method without any other equipment is proposed in this paper. In this method, G(s) is simplified to estimate N(t) using N′(t) = ANm(t − τ), which is used for compensation. The gain A and delay τ can be obtained by analysis of the data acquired by the absolute gravimeter. The experiments are conducted with the homemade absolute gravimeter T-1 and repeated for 75 times. The standard deviation of the uncompensated results is 3276 μGal (1 μGal = 1 × 10−8 m/s2), while that of the compensated results is 167 μGal. The compensation method not only achieves a reduction by nearly a factor of 20, but also can be simply used without any other equipment. The results indicate that the method basically meets the demands of absolute gravimeters. In the future, it may be applied to dynamic absolute gravity measurement and take the place of vibration isolators.

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Effects of Solvents on the Electrical Resistance of Poly(3,4-ethylenedioxythiophene) on Textiles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.16 ◽

2012 ◽

Vol 441 ◽

pp. 16-22 ◽

Cited By ~ 2

Author(s):

Serkan Yildiz ◽

Jin Lin Cai ◽

Qin Guo Fan

Keyword(s):

Electrical Resistance ◽

Chemical Resistance ◽

Morphological Changes ◽

Chemical Treatments ◽

Before And After ◽

Order Of Magnitude ◽

Polyester Textile ◽

Coated Fabrics ◽

Vapor Phase Polymerization ◽

Almost All

The chemical resistance of Poly-3,4-ethylenedioxythiophene (PEDOT) was tested in both organic and inorganic solvents including Chloroform, DMSO, Xylene, THF, sulfuric acid, sodium hydroxide and sodium chloride. PEDOT was synthesized via the vapor-phase polymerization and coated on PET/cotton, cotton and polyester textile substrates. Electrical resistances of the PEDOT were measured both before and after chemical treatments. The morphological changes after treatments were studied by scanning electron microscope (SEM). The PEDOT coated fabrics demonstrated excellent chemical-resistant property since its electrical resistance maintained on the order of magnitude of 100 ohm after treatment in almost all the solvents except NaOH with which a remarkable increasing of electrical resistance occurred due to disappearing PEDOT from the substrate indicating its potential to be a good solvent for PEDOT.

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