Design and Simulation of Capacitive Micromechaned Gyroscope

By researching and investigating the structure of capacitive gyroscopes, A novel capacitive micromachined gyroscope is proposed and the structure is designed. The method of electrostatic comber drive, capacitive detection of bar structure is used for the structure, and these make the gyroscope high sensitivity. The main air damping of the drive mode and detection mode is slide film damping, it is possible to make the gyroscope achieve high Q-values at atmospheric pressure. The decoupled gyroscope is designed, too. By large numbers of simulation analysis， frequencies of the first six steps mode are gained, nature frequencies of drive mode and sense mode of gyroscope are a close match, and rationality of the structure is validated. At last, the structure encapsulated is presented.

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Collision Induced Microwave Absorption in N2, CH4, and N2–Ar, N2–CH4 Mixtures at 1.1 and 2.3 cm−1

Canadian Journal of Physics ◽

10.1139/p74-112 ◽

1974 ◽

Vol 52 (9) ◽

pp. 821-829 ◽

Cited By ~ 8

Author(s):

I. R. Dagg ◽

G. E. Reesor ◽

J. L. Urbaniak

Keyword(s):

Microwave Absorption ◽

Quadrupole Moment ◽

Linear Dependence ◽

Relaxation Times ◽

High Sensitivity ◽

Higher Order ◽

Induced Absorption ◽

High Q ◽

Order Dependence

Collision induced microwave absorption is reported in pure N2, N2–Ar, N2–CH4, mixtures, and in pure CH4 in the 35 and 70 GHz regions (1.1 and 2.3 cm−1) at a temperature of 22 °C. The measurements are accomplished using overmoded high Q cavities capable of pressurization of up to 5000 p.s.i.g. The apparatus and method are described. With the high sensitivity attained, the results in pure N2 from 30 → 250 amagat reveal terms in the square and cube of the density from which the relaxation times are calculated. The linear dependence on frequency of the collision induced absorption up to 2.3 cm−1 is established. Higher order dependence on the density is observed in the N2–Ar and N2–CH4 mixtures. Various estimates of the quadrupole moment of N2 are given, making use of earlier results in other frequency regions.

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High sensitivity and high Q-factor nanoslotted parallel quadrabeam photonic crystal cavity for real-time and label-free sensing

Applied Physics Letters ◽

10.1063/1.4867254 ◽

2014 ◽

Vol 105 (6) ◽

pp. 063118 ◽

Cited By ~ 77

Author(s):

Daquan Yang ◽

Shota Kita ◽

Feng Liang ◽

Cheng Wang ◽

Huiping Tian ◽

...

Keyword(s):

Photonic Crystal ◽

Real Time ◽

High Sensitivity ◽

Q Factor ◽

Label Free ◽

Photonic Crystal Cavity ◽

High Q

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A bulk micromachined gyroscope with improved quality-factors at atmospheric pressure

10.1117/12.779200 ◽

2007 ◽

Author(s):

Weiping Chen ◽

Hong Chen ◽

Xiaowei Liu ◽

Tian Han ◽

Hao Wang

Keyword(s):

Atmospheric Pressure ◽

Quality Factors ◽

Micromachined Gyroscope

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2D Propagation Simulation of Variation Parameters of U-shape Fiber Optic

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.b2082.1210220 ◽

2020 ◽

Vol 10 (2) ◽

pp. 153-158

Keyword(s):

Fiber Optics ◽

Power Flow ◽

Fiber Optic ◽

Power Transmission ◽

Simulation Analysis ◽

Reducing Power ◽

High Sensitivity ◽

Curvature Radius ◽

Sensor Applications ◽

Core Fiber

Fiber optic has extraordinary properties and is suitable in sensor applications due to its special potential. Currently, macro bending characteristics of newly developed hetero core fiber optic element are designed and evaluated. This paper presents the preliminary results obtained from the numerical simulation analysis of the bending sensitivity of U-shape fiber optics toward the 2D electromagnetic wave in terms of mesh, curvature radius, core fiber size, and turn number. Fiber optics with core sizes of 4, 9, 50, and 62.5 μm were designed. In addition, the combination of core diameters 50-4-50, 50-9-50, 62.5-4-62.5, and 62.5-9-62.5 μm is evaluated to compare the outcome of transmission power in terms of hetero core structure of fiber optic. Simulation is performed using COMSOL Multiphysics simulation tool. The developed U-shape fiber optic is designed to sense the distortion of reducing power transmission by comparing input and output power. Results show that the selected mesh depends on the size of geometry bending fiber optics, and fine and finer mesh is the best for U-shape fiber optic. Furthermore, the power flow on the fiber decreases with the decreasing curvature radius and increasing turn number. The fiber with a core size combination of 62.5–4–62.5 um has high sensitivity in terms of loss. The attained results possess higher potential in the field of sensor applications, such as displacement, strain, pressure, and monitoring respiration, on human body. This study serves as a basis for further investigation of nanomaterial coating on fiber optics, thereby enhancing its credibility for sensing.

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Impedance Screening for Preschool Children: State of the Art

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947908800110 ◽

1979 ◽

Vol 88 (1) ◽

pp. 56-65 ◽

Cited By ~ 14

Author(s):

Jack L. Paradise ◽

Clyde G. Smith

Keyword(s):

Preschool Children ◽

Middle Ear ◽

Large Scale ◽

High Sensitivity ◽

Cutoff Point ◽

Screening Programs ◽

Large Numbers ◽

Middle Ear Disease ◽

High Degree ◽

Large Scale Screening

As a test for detecting middle ear disease among preschool children, tympanometry — as opposed to audiometry — has three advantageous attributes: a high degree of sensitivity, minimal need for subject cooperation, and total objectivity. For these reasons interest has arisen in tympanometry as a method for screening, i.e., identifying children with previously undetected middle ear disease. However, uncertainty persists concerning the importance of detecting apparently asymptomatic middle ear effusions, and concerning optimal methods, or even the advisability, of treating them. Further, the sensitivity and specificity of tympanometry depend on how the pass-fail cutoff point is defined. Defining this cutoff point so as to achieve high sensitivity may result in excessively low specificity, with the production of large numbers of false-positives who then become overreferrals. Data are presented to show how the validity of the test may be increased to some extent by attention to the gradient of “negative-pressure” tympanograms. At the present time, given the various aforementioned uncertainties, and with adequate validation as to the presence or absence of disease often lacking in reported studies of impedance screening in preschool populations, the cumulative results of these studies do not warrant embarking on large-scale screening programs. What is needed instead is additional research to explore the issue further.

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Simulation Analysis on the Designing of High-Q Terahertz Metamaterials

Chinese Journal of Lasers ◽

10.3788/cjl201643.0106005 ◽

2016 ◽

Vol 43 (1) ◽

pp. 0106005

Author(s):

邢维 Xing Wei ◽

延凤平 Yan Fengping ◽

谭思宇 Tan Siyu ◽

刘硕 Liu Shuo ◽

李立朝 Li Lizhao

Keyword(s):

Simulation Analysis ◽

High Q ◽

Terahertz Metamaterials

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Cellulose Acetate Electrophoresis of Alkaline Phosphatase Isoenzymes in Human Serum and Tissue

Clinical Chemistry ◽

10.1093/clinchem/18.5.417 ◽

1972 ◽

Vol 18 (5) ◽

pp. 417-421 ◽

Cited By ~ 41

Author(s):

H A Fritsche ◽

H R Adams-Park

Keyword(s):

Alkaline Phosphatase ◽

Human Serum ◽

Cellulose Acetate ◽

High Sensitivity ◽

Heat Inactivation ◽

Cellulose Acetate Electrophoresis ◽

Electrophoretic Method ◽

Large Numbers ◽

Alkaline Phosphatase Isoenzymes ◽

Isoenzyme Patterns

Abstract We describe a new electrophoretic method for the characterization of human serum and tissue alkaline phosphatases on cellulose acetate plates. Enzymes are localized fluorometrically with the substrate α-naphthol AS-MX phosphate or colorimetrically by coupling the reaction product with Fast Blue RR. Both localization techniques are sensitive enough to demonstrate isoenzyme patterns in micro-scale samples of normal sera. Our electrophoretic studies indicate that sera of children and adults normally contain isoenzymes originating from both liver and bone. The high sensitivity of the method allows the use of normal sera as markers rather than tissue extracts, and isoenzyme patterns may be visually assessed after heat inactivation and chemical inhibition. The method is suitable for the electrophoretic fractionation of alkaline phosphatase in large numbers of sera, with equipment and technique familiar to many laboratories.

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Spirulina is an effective dietary source of zeaxanthin to humans

British Journal Of Nutrition ◽

10.1017/s0007114511005885 ◽

2012 ◽

Vol 108 (4) ◽

pp. 611-619 ◽

Cited By ~ 13

Author(s):

Bolan Yu ◽

Jie Wang ◽

Paolo M. Suter ◽

Robert M. Russell ◽

Michael A. Grusak ◽

...

Keyword(s):

Single Dose ◽

Atmospheric Pressure ◽

High Sensitivity ◽

Relative Bioavailability ◽

Age Related Macular Degeneration ◽

High Concentration ◽

Age Related ◽

Pressure Chemical ◽

Human Eyes ◽

Chinese Subjects

Zeaxanthin is a predominant xanthophyll in human eyes and may reduce the risk of cataracts and age-related macular degeneration. Spirulina is an algal food that contains a high concentration of zeaxanthin. In order to determine the zeaxanthin bioavailability of spirulina for dietary supplementation in humans, spirulina was grown in nutrient solution with2H2O for carotenoid labelling. Single servings of2H-labelled spirulina (4·0–5·0 g) containing 2·6–3·7 mg zeaxanthin were consumed by fourteen healthy male volunteers (four Americans and ten Chinese) with 12 g dietary fat. Blood samples were collected over a 45 d period. The serum concentrations of total zeaxanthin were measured using HPLC, and the enrichment of labelled zeaxanthin was determined using LC-atmospheric pressure chemical ionisation-MS (LC-APCI-MS). The results showed that intrinsically labelled spirulina zeaxanthin in the circulation was detected at levels as low as 10 % of the total zeaxanthin for up to 45 d after intake of the algae. A single dose of spirulina can increase mean serum zeaxanthin concentration in humans from 0·06 to 0·15 μmol/l, as shown in our study involving American and Chinese volunteers. The average 15 d area under the serum zeaxanthin response curve to the single dose of spirulina was 293 nmol × d/μmol (range 254–335) in American subjects, and 197 nmol × d/μmol (range 154–285) in Chinese subjects. It is concluded that the relative bioavailability of spirulina zeaxanthin can be studied with high sensitivity and specificity using2H labelling and LC-APCI-MS methodology. Spirulina can serve as a rich source of dietary zeaxanthin in humans.

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