Vibration detection and reconstruction based on Φ-OTDR with dual AOM

By introducing the principle,classification and characteristics of optical fiber sensor ,we can understand the optical fiber sensor to some extent.Based on this,it introduces a filter which is used in lockmaking industry.This device is mainly made up of vibrating disk,optical fiber sensor and solenoid valve.By this filter,including vibration,detection and blowing,we can distinguish different kinds of marbles, also,we can distinguish the front-end and back-end of some kind of mables to meet special need.In this case,just connecting every part to each other and make a special angle of fiber head,then,the filter can distinguish marbles automatically an it improves the efficiency heavily.

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Disentangling ‘sciatica’ to understand and characterise somatosensory profiles and potential pain mechanisms

Scandinavian Journal of Pain ◽

10.1515/sjpain-2021-0058 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Brigitte Tampin ◽

Christopher Lind ◽

Angela Jacques ◽

Helen Slater

Keyword(s):

Mechanical Vibration ◽

Radicular Pain ◽

Leg Pain ◽

Heat Sensitivity ◽

Loss Of Function ◽

Pain Mechanisms ◽

Vibration Detection ◽

Lumbar Radicular Pain ◽

Pain Experiences ◽

Pain Descriptors

Abstract Objectives The study aimed to investigate if patients with lumbar radicular pain only and those with combined lumbar radicular pain + radiculopathy differ in their somatosensory profiles and pain experiences. Methods Quantitative sensory testing (QST) was performed in 26 patients (mean age 47 ± 10 years, 10 females) with unilateral leg pain in the L5 or S1 distribution in their main pain area (MPA) and contralateral mirror side, in the relevant foot dermatome on the symptomatic side and in the hand dorsum. Pain experience was captured on the painDETECT. Results Eight patients presented with lumbar radicular pain only and 18 patients with combined radicular pain + radiculopathy. Patients with radicular pain only demonstrated widespread loss of function (mechanical detection) bilaterally in the MPA (p<0.003) and hand (p=0.002), increased heat sensitivity in both legs (p<0.019) and cold/heat sensitivity in the hand (p<0.024). QST measurements in the dermatome did not differ compared to HCs and patients with radiculopathy. Patients with lumbar radiculopathy were characterised by a localised loss of function in the symptomatic leg in the MPA (warm, mechanical, vibration detection, mechanical pain threshold, mechanical pain sensitivity p<0.031) and dermatome (mechanical, vibration detection p<0.001), consistent with a nerve root lesion. Pain descriptors did not differ between the two groups with the exception of numbness (p<0.001). Patients with radicular pain did not report symptoms of numbness, while 78% of patients with radiculopathy did. Conclusions Distinct differences in somatosensory profiles and pain experiences were demonstrated for each patient group, suggesting differing underlying pain mechanisms.

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