scholarly journals Conical Microstructure Flexible High-Sensitivity Sensing Unit Adopting Chemical Corrosion

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4613
Author(s):  
Yangyang Wang ◽  
Jiangyu Deng ◽  
Junping Duan ◽  
Binzhen Zhang

Sensor technology is one of the three pillars of information technology. This paper aims to discuss the problems of insensitive detection, poor stability, and uncomfortable wearing of sensors in the fields of human–computer interaction, 5G communication, and medical detection. A sensing unit with a microstructured flexible sensing front end is a cone-like structure with a single size of 18–22 μm. They are evenly distributed and can reach 2500 units per square millimeter. In the pressure range, the sensitivity of the sensor unit is 0.6 KPa−1 (no microstructure sensitivity at 0.15 KPa−1), and the response time is fast (<600 ms). After 400 repeated stretching experiments, the sensor unit can still maintain a stable output signal. Due to its flexible characteristics (50% tensile conductivity), the sensor unit can act on human skin and other curved surfaces. According to the prepared sensing unit, good test results can be obtained on the testing of mechanical devices, curved surfaces of human bodies, and non-contact methods. It is observed that the flexible sensor can be applied to various test occasions, and the manufacturing process of the sensing unit will provide new ideas and methods for the preparation of the flexible sensor technology.

2021 ◽  
Vol 13 (7) ◽  
pp. 1261
Author(s):  
Riccardo Roncella ◽  
Nazarena Bruno ◽  
Fabrizio Diotri ◽  
Klaus Thoeni ◽  
Anna Giacomini

Digital surface models (DSM) have become one of the main sources of geometrical information for a broad range of applications. Image-based systems typically rely on passive sensors which can represent a strong limitation in several survey activities (e.g., night-time monitoring, underground survey and night surveillance). However, recent progresses in sensor technology allow very high sensitivity which drastically improves low-light image quality by applying innovative noise reduction techniques. This work focuses on the performances of night-time photogrammetric systems devoted to the monitoring of rock slopes. The study investigates the application of different camera settings and their reliability to produce accurate DSM. A total of 672 stereo-pairs acquired with high-sensitivity cameras (Nikon D800 and D810) at three different testing sites were considered. The dataset includes different camera configurations (ISO speed, shutter speed, aperture and image under-/over-exposure). The use of image quality assessment (IQA) methods to evaluate the quality of the images prior to the 3D reconstruction is investigated. The results show that modern high-sensitivity cameras allow the reconstruction of accurate DSM in an extreme low-light environment and, exploiting the correct camera setup, achieving comparable results to daylight acquisitions. This makes imaging sensors extremely versatile for monitoring applications at generally low costs.


2010 ◽  
Vol 152-153 ◽  
pp. 192-196
Author(s):  
Ju Hua Huang ◽  
Ming Cao ◽  
Hang Guo

The performance of power lithium batteries directly affects the performance of electric vehicles. To ensure the safety of power lithium batteries and improve battery life, this paper uses Ricoh R5408 Series Li-ion battery protection IC to design the high-current protection board for electric vehicle, to achieve the power lithium battery group overcharge protection, over-discharge protection, over current, short circuit protection, temperature protection and charge balance protection, and has run on the pure electric vehicles with good test results.


2018 ◽  
Vol 90 (5) ◽  
pp. 562-569 ◽  
Author(s):  
Matthias Pawlowski ◽  
Viktoria Joksch ◽  
Heinz Wiendl ◽  
Sven G Meuth ◽  
Thomas Duning ◽  
...  

ObjectivesFrontotemporal dementia (FTD) is a heterogeneous clinical syndrome linked to diverse types of underlying neuropathology. Diagnosis is mainly based on clinical presentation and accurate prediction of underlying neuropathology remains difficult.MethodsWe present a large cohort of patients with FTD spectrum diseases (n=84). All patients were thoroughly characterised by cerebrospinal fluid (CSF) Alzheimer’s disease (AD) biomarkers, neuroimaging, neuropsychological testing and standardised apraxia screening.ResultsA potential AD pathology was found in 43% of patients with FTD. CSF AD biomarker levels positively correlated with AD-typical apraxia scores in patients with FTD. The discriminative power of apraxia test results indicative of AD pathology was high (sensitivity: 90%, specificity: 66%).ConclusionsApraxia is common in neurodegenerative dementias but under-represented in clinical workup and diagnostic criteria. Standardised apraxia screening may serve as bedside test to objectify an AD-typical apraxia profile as an early and robust sign of AD pathology in patients with FTD.


2020 ◽  
Vol 185 ◽  
pp. 04042
Author(s):  
Tao Tian ◽  
Shanyu Liu ◽  
Rong Wang ◽  
Ying Lei ◽  
Changlin Zheng

Chemical resistance is one of the important evaluation factors of ceramic tiles. This article describes the method for determining the chemical resistance of ceramic tiles, and discusses the influence of acid-base solution concentration on the test results during the experiment, and proposes corresponding improvement measures.


1977 ◽  
Author(s):  
H.H. Brackmann ◽  
P. Hoffmann ◽  
F. Etzel ◽  
Eqli H. Hildenbrand

In the FRG the work of several centers is concerned with introducing a program of self-treatment for hemophi1iacso The general goal of a self-treatment-program is: avoidance of a time lag due to long distances and the expansion of personal freedom and life style possibilities.In respect to the dosage and treatment duration various opinions exist, some of them differing quite noticably from ours. Our conception about the therapy, existing since the beginning of our program (June 1971), is based on an intensive cooperation with the department of orthopedics at the university. Through our teamwork the following results were achieved:- the evaluation of 17.196 acute bleedings registered 93% joint and muscle bleedings- 98% of the patients over 11 years of age with severe and semi-severe hemophilia A or B revealed at least one, in several cases more, arthropathic changes- the pathophysiological process of a joint bleeding leads to an important electromyographic test as well as to new ideas about biomechanic.Based on the general test results a specific dosage plan for each patient resulted, which, together with the orthopedic findings took into consideration the attained biological recovery. Since our goal is the strenghtening and training of muscle in general, every patient receives a specially adopted training program, which largely excludes bleeding. Our results have lead to a 90% improvement of the original orthopedic finding.


2020 ◽  
Vol 3 (1) ◽  
pp. 26-40
Author(s):  
Manorama Singh ◽  
Smita R. Bhardiya ◽  
Fooleswar Verma ◽  
Vijai K. Rai ◽  
Ankita Rai

At present, graphene is one of the most up-to-date materials and it can be applied for various energy conversion devices and sensor technology. In this review article, our main focus is to summarize the role of graphene and its modified surface leading to develop hybrid nanomaterials and its applications in fabrication of pesticide sensor. Graphene based materials demonstrate exclusive electrochemical and optical properties as well as compatibility to absorb a variety of bio-molecules through π-π stacking interaction and/or electrostatics interaction, which make them ideal material to be employed in sensor application. The role of graphene is very crucial in preparing different unique and desirable hybrid functional composites along with nanoparticles, redox mediators, conducting polymers etc. to improve the performance of the sensors. Therefore, they can be easily used as a suitable material applying in fabrication of electrochemical sensors/ biosensors for the detection of organophosphorous and carbamate pesticides. A number of most recent reported works were discussed in which graphene-based hybrid composites show high sensitivity, good catalytic activity, selectivity towards the determination of pesticide either enzymatically or nonenzymatically. The properties of graphene (exceptional charge transport, thermal, optical, mechanical, high surface area, large pore volume and size, an opened ordered structure) play an important role in pesticide detection.


2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Tahsin Gürpınar ◽  
Barış Polat ◽  
Ayşe Esin Polat ◽  
Engin Çarkçı ◽  
Yusuf Öztürkmen

Background. The aim of this study is to determine the diagnostic accuracy of lever sign test in acute, chronic, and postreconstructive ACL injuries. Methods. In total, 78 patients (69 male, 9 female) were subjected to clinical instability tests including Lachman, anterior drawer, pivot shift, and lever sign when an injury of the ACL was suspected. All tests were performed bilaterally in all patients in acute, chronic period and patients who underwent surgery after the anaesthesia and after the reconstruction at the last follow-up by two senior orthopaedic surgeons. MRI was taken from all patients and MRI image was taken as the reference test when evaluating the accuracy of the tests. Results. The mean age of patients was 26.2±6.4 years (range, 17-44 years). Sensitivity and accuracy values of the Lachman, anterior drawer, pivot shift, and lever tests in the acute phase were calculated as 80.6%, 77.4%, 51.6%, 91.9% and 76.9%, 75.6%, 60.3%, 92.3%, respectively, and in the chronic (preanaesthesia) phase were calculated as 83.9%, 79.0%, 56.5%, 91.9% and 80.8%, 78.2%, 64.1%, 92.3%, respectively. Lachman, anterior drawer, pivot shift, and lever sign Acute’s significant [AUC: 0.716, 0.731, 0.727, 0.928, respectively] activity were observed in the prediction of ACL rupture in MRI. Conclusion. An ideal test to diagnose the integrity of the ACL should be easy to perform and reproducible with high sensitivity and specificity. From this perspective, the lever test seems to be a good test for clinicians in acute, chronic and postreconstructive ACL injuries.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Ming-yi Zhang ◽  
Zheng Kuang ◽  
Xiao-yu Bai ◽  
Xiao-yu Chen

Building anti-floating anchors have been increasingly used in recent years, but conventional steel anchors under service conditions are easily subjected to chemical erosion. Glass fiber reinforcement polymer (GFRP) is a promising solution to this problem. In this study, field pullout tests were conducted on three full instrumented GFRP anti-floating anchors in weathered granite. Specifically, the GFRP anchors during pultrusion were innovatively embedded with bare fiber Bragg grating (FBG) sensors to monitor the axial force distribution along depth. It was found that the embedded FBG could reliably monitor the axial force distribution of GFRP anchors. The ultimate pullout force of a GFRP anchor with diameter of 28 mm and anchorage length of 5 m was up to 400 kN. The GFRP anchor yielded at 0.8 m underground. Force distribution and field photos at failure indicated shear failure occurred at the anchor/bolt interface at the end of the tests. The feasibility of the GFRP anti-floating anchor was also verified in civil engineering. Finally, an elastic mechanical model and Mindlin’s displacement solution are used to get distribution functions of axial force and shear stress along the depth, and the results accord with the test results.


2019 ◽  
Vol 11 (17) ◽  
pp. 2012 ◽  
Author(s):  
Chein-I Chang ◽  
Meiping Song ◽  
Junping Zhang ◽  
Chao-Cheng Wu

Due to advent of sensor technology, hyperspectral imaging has become an emerging technology in remote sensing. Many problems, which cannot be resolved by multispectral imaging, can now be solved by hyperspectral imaging. The aim of this Special Issue “Hyperspectral Imaging and Applications” is to publish new ideas and technologies to facilitate the utility of hyperspectral imaging in data exploitation and to further explore its potential in different applications. This Special Issue has accepted and published 25 papers in various areas, which can be organized into 7 categories, Data Unmixing, Spectral variability, Target Detection, Hyperspectral Image Classification, Band Selection, Data Fusion, Applications.


Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4988
Author(s):  
Chunpeng Ai ◽  
Xiaofeng Zhao ◽  
Dianzhong Wen

In order to improve the output sensitivity of the piezoelectric acceleration sensor, this paper proposed a high sensitivity acceleration sensor based on a piezoelectric metal oxide semiconductor field effect transistor (MOSFET). It is constituted by a piezoelectric beam and an N-channel depletion MOSFET. A silicon cantilever beam with Pt/ZnO/Pt/Ti multilayer structure is used as a piezoelectric beam. Based on the piezoelectric effect, the piezoelectric beam generates charges when it is subjected to acceleration. Due to the large input impedance of the MOSFET, the charge generated by the piezoelectric beam can be used as a gate control signal to achieve the purpose of converting the output charge of the piezoelectric beam into current. The test results show that when the external excitation acceleration increases from 0.2 g to 1.5 g with an increment of 0.1 g, the peak-to-peak value of the output voltage of the proposed sensors increases from 0.327 V to 2.774 V at a frequency of 1075 Hz. The voltage sensitivity of the piezoelectric beam is 0.85 V/g and that of the proposed acceleration sensor was 2.05 V/g, which is 2.41 times higher than the piezoelectric beam. The proposed sensor can effectively improve the voltage output sensitivity and can be used in the field of structural health monitoring.


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