scholarly journals High-Resolution, Non-Contact Angular Measurement System for PSA/RSA

2011 ◽  
Author(s):  
Ronald Sloat ◽  
Jianbiao Pan
Keyword(s):  
Measurement System ◽  
Continuous Measurement ◽  
Disk Drive ◽  
Disk Surface ◽  
Angular Measurement ◽  
Hard Drives ◽  
Hard Drive ◽  
Final Assembly ◽  
Position Sensitive

A non-contact angular measurement system for Pitch Static Attitude (PSA) and Roll Static Attitude (RSA) of hard disk drive sliders is designed and built. Real-time sampling at over 15 KHz is achieved with accuracy of +/−0.05 degrees over a range of approximately 2–3 degrees. Measuring the PSA and RSA is critical for hard drive manufacturers to control and improve the quality and reliability of hard drives. Although the hard drive industry is able to measure the PSA and RSA at the subassembly level at this time, there is no system available that is able to measure PSA/RSA at the final assembly level. This project has successfully demonstrated a methodology that the PSA/RSA can be reliably measured in-situ using a laser and position sensitive detector (PSD) technology. A prototype of the measurement system has been built. This device will allow a continuous measurement between the parked position on the ramp and the loading position just off of the disk surface. This measured data can be used to verify manufacturing processes and reliability data.

Reallocated Sectors Count Parameter for Analysing Hard Disk Drive Reliability

2019 ◽  
Vol 16 (12) ◽  
pp. 5298-5302
Author(s):  
Iskandar Nailovich Nasyrov ◽  
Ildar Iskandarovich Nasyrov ◽  
Rustam Iskandarovich Nasyrov ◽  
Bulat Askarovich Khairullin
Keyword(s):  
Operating Time ◽  
Disk Drive ◽  
Disk Surface ◽  
Information Storage ◽  
Hard Drives ◽  
Storage Devices ◽  
Reliability Parameters ◽  
Individual Assessment ◽  
Scientific Task ◽  
Rate Frequency

The dependence of the SMART parameter 5 Reallocated sectors count value change on the operating time characterising the number of reallocated sectors is considered. This parameter is critical in the sense that if the attribute value increases, this may indicate deterioration in the state of the disk surface. The scientific task of the study is to establish relationships in the failed hard drives between the specified parameter and the values of other reliability parameters for information stores of various manufacturers. In the course of the study, the drives of the HGST, Hitachi, Samsung, ST, Toshiba, WDC trademarks operated in the Backblaze largest commercial data centre were analysed. The analysis revealed a relationship between the specified parameter and the parameters 1 Read error rate (frequency of errors (when reading data from the disk), the origin of which is due to the hardware of the disk), 196 Reallocation event count (number of reallocation operations), 197 Current pending sector count (number of sectors that are candidates for reallocation). It is shown that the nature of the change in the values of the considered parameters depends on the manufacturer of information storage devices. It is proposed to perform an individual assessment of the reliability of hard drives using the parameters identified as a result of the study.

scholarly journals Monitoring of compliance with fuel sulfur content regulations through unmanned aerial vehicle (UAV) measurements of ship emissions

2019 ◽  
Vol 12 (11) ◽  
pp. 6113-6124 ◽  
Author(s):  
Fan Zhou ◽  
Shengda Pan ◽  
Wei Chen ◽  
Xunpeng Ni ◽  
Bowen An
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Sulfur Content ◽  
Measurement System ◽  
Yangtze River Delta ◽  
Exhaust Gas ◽  
Ship Emissions ◽  
Chemical Examination ◽  
Airborne Measurements ◽  
Aerial Vehicle

Abstract. Air pollution from ship exhaust gas can be reduced by the establishment of emission control areas (ECAs). Efficient supervision of ship emissions is currently a major concern of maritime authorities. In this study, a measurement system for exhaust gas from ships based on an unmanned aerial vehicle (UAV) was designed and developed. Sensors were mounted on the UAV to measure the concentrations of SO2 and CO2 in order to calculate the fuel sulfur content (FSC) of ships. The Waigaoqiao port in the Yangtze River Delta, an ECA in China, was selected for monitoring compliance with FSC regulations. Unlike in situ or airborne measurements, the proposed measurement system could be used to determine the smoke plume at about 5 m from the funnel mouth of ships, thus providing a means for estimating the FSC of ships. In order to verify the accuracy of these measurements, fuel samples were collected at the same time and sent to the laboratory for chemical examination, and these two types of measurements were compared. After 23 comparative experiments, the results showed that, in general, the deviation of the estimated value for FSC was less than 0.03 % (m/m) at an FSC level ranging from 0.035 % (m/m) to 0.24 % (m/m). Hence, UAV measurements can be used for monitoring of ECAs for compliance with FSC regulations.

Verification of In Situ Thresholds and Integrated Real-Ear Measurements

2010 ◽  
Vol 21 (10) ◽  
pp. 663-670 ◽  
Author(s):  
Jeffrey J. DiGiovanni ◽  
Ryan M. Pratt
Keyword(s):  
Measurement System ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Normal Hearing ◽  
Analysis Tool ◽  
Ohio University ◽  
Positive Direction ◽  
Significant Difference ◽  
Threshold Measurement

Background: Accurate prescriptive gain results in a more accurate fit, lower return rate in hearing aids, and increased patient satisfaction. In situ threshold measurements can be used to determine required gain. The Widex Corporation uses an in situ threshold measurement strategy, called the Sensogram. Real-ear measurements determine if prescriptive gain targets have been achieved. Starkey Laboratories introduced an integrated real-ear measurement system in their hearing aids. Purpose: To determine whether the responses obtained using the Widex Sensogram were equivalent to those obtained using current clinical threshold measurement methods. To determine the accuracy of the Starkey IREMS™ (Integrated Real Ear Measurement System) in measuring RECD (real-ear to coupler difference) values compared to a dedicated real-ear measurement system. Research Design: A verification design was employed by comparing participant data measured from standard, benchmark equipment and procedures against new techniques offered by hearing-aid manufacturers. Study Sample: A total of 20 participants participated in this study. Ten participants with sensorineural hearing loss were recruited from the Ohio University Hearing, Speech, and Language Clinic participated in the first experiment. Ten participants with normal hearing were recruited from the student population at Ohio University participated in both experiments. The normal-hearing group had thresholds of 15 dB HL or better at the octave frequencies of 250–8000 Hz. The hearing-impaired group had thresholds of varying degrees and configurations with thresholds equal to or poorer than 25 dB HL three-frequency pure-tone average. Data Collection and Analysis: The order of measurement method for both experiments was counterbalanced. In Experiment 1, thresholds obtained via the Widex Sensogram were compared to thresholds obtained for each participant using a clinical audiometer and ER-3A insert ear phones. In Experiment 2, RECD values obtained via the Starkey IREMS were compared to RECD values obtained via the Audioscan Verifit™. A repeated-measures analysis of variance (ANOVA) was used for statistical analysis, and a Fisher's LSD (least significant difference) was used as a post hoc analysis tool. Results: A significant difference between Sensogram thresholds and conventional audiometric thresholds was found with the Sensogram method resulting in better threshold values at 0.5, 1.0, and 2.0 kHz for both groups. In Experiment 2, a significant difference between RECD values obtained by the Starkey IREMS and the Audioscan Verifit system was found with significant differences in RECD values found at 0.25, 0.5, 0.75, 1.5, 2.0, and 6.0 kHz. Conclusions: The Sensogram data differ significantly from traditional audiometry at several frequencies important for speech intelligibility. Real-ear measures are still required for verification of prescribed gain, however, calling into question any claims of shortened fitting time. The Starkey IREMS does perform real-ear measurements that vary significantly from benchmark equipment. These technologies represent a positive direction in prescribing accurate gain during hearing-aid fittings, but a stand-alone system is still the preferred method for real-ear measurements in hearing-aid fittings.

scholarly journals Strain Sensing With Piezoelectric Zinc Oxide Thin Films for Vibration Suppression in Hard Disk Drives

2008 ◽  
Author(s):  
Sarah Felix ◽  
Stanley Kon ◽  
Jianbin Nie ◽  
Roberto Horowitz
Keyword(s):  
Vibration Suppression ◽  
Transfer Functions ◽  
Hard Disk Drives ◽  
Hard Disk ◽  
Disk Drive ◽  
Strain Sensing ◽  
Linear Quadratic ◽  
H2 Control ◽  
Hard Drives ◽  
Optimization Methodology

This paper describes the integration of thin film ZnO strain sensors onto hard disk drive suspensions for improved vibration suppression for tracking control. Sensor location was designed using an efficient optimization methodology based on linear quadratic gaussian (LQG) control. Sensors were fabricated directly onto steel wafers that were subsequently made into instrumented suspensions. Prototype instrumented suspensions were installed into commercial hard drives and tested. For the first time, a sensing signal was successfully obtained while the suspension was flying on a disk as in normal drive operation. Preliminary models were identified from experimental transfer functions. Nominal H2 control simulations demonstrated improved vibration suppression as a result of both the better resolution and higher sensing rate provided by the sensors.

scholarly journals Integrating a FISH imaging system into the cytology laboratory

CytoJournal ◽  
2010 ◽  
Vol 7 ◽  
pp. 3 ◽  
Author(s):  
G. Denice Smith ◽  
Matt Riding ◽  
Kim Oswald ◽  
Joel S. Bentz
Keyword(s):  
Training Programs ◽  
Imaging System ◽  
Job Descriptions ◽  
Hard Drives ◽  
Financial Investment ◽  
Automated Scanning ◽  
Space Requirements ◽  
And Training

We have implemented an interactive imaging system for the interpretation of UroVysion fluorescence in situ hybridization (FISH) to improve throughput, productivity, quality control and diagnostic accuracy. We describe the Duet imaging system, our experiences with implementation, and outline the financial investment, space requirements, information technology needs, validation, and training of cytotechnologists needed to integrate such a system into a cytology laboratory. Before purchasing the imaging system, we evaluated and validated the instrument at our facility. Implementation required slide preparation changes, IT modifications, development of training programs, and revision of job descriptions for cytotechnologists. A darkened room was built to house the automated scanning station and microscope, as well as two imaging stations. IT changes included generation of storage for archival images on the LAN, addition of external hard drives for back-up, and changes to cable connections for communication between remote locations. Training programs for cytotechnologists, and pathologists/fellows/residents were developed, and cytotechnologists were integrated into multiple steps of the process. The imaging system has resulted in increased productivity for pathologists, concomitant with an expanded role of cytotechnologists in multiple critical steps, including FISH, scan setup, reclassification, and initial interpretation.

Continuous measurement of gas partial pressures in intracerebral tissue

1978 ◽  
Vol 44 (4) ◽  
pp. 528-533 ◽  
Author(s):  
J. Seylaz ◽  
E. Pinard
Keyword(s):  
Continuous Measurement ◽  
Fast Response ◽  
Base Line ◽  
Partial Pressures ◽  
Mass Spectrograph ◽  
Present Technique ◽  
Gas Molecules ◽  
The Brain ◽  
Thin Polyethylene

A mass spectrograph technique has been developed for measurement of physiological gas partial pressures locally in the brain. The sampling cannula is implanted stereotaxically and remains in situ for several weeks. It is a thin cylinder in shape, and is covered with a thin polyethylene membrane across which gas molecules can be sampled continuously. The conductance of this membrane is well adapted to the limited rate of replacement of gas molecules afforded by the cerebral tissue, hence there is no depletion around the cannula; this depletion has until now been the major problem of this technology. The present technique provides a continuous measurement with fast response time, which is directly proportional to the partial pressures of the gases. The variations can be expressed as a percentage of the base-line value.

scholarly journals In situ noncontact measurement system and two-step compensation strategy for ultra-precision diamond machining

2018 ◽  
Vol 26 (23) ◽  
pp. 30724 ◽  
Author(s):  
Jun Yu ◽  
Zhengxiang Shen ◽  
Xiaoqiang Wang ◽  
Pengfeng Sheng ◽  
Zhanshan Wang
Keyword(s):  
Measurement System ◽  
Compensation Strategy ◽  
Noncontact Measurement ◽  
Diamond Machining ◽  
Ultra Precision
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