Characterization of a MEMS Accelerometer Considering Environmental Temperature Fluctuations

2011 ◽  
Vol 697-698 ◽  
pp. 801-804 ◽  
Author(s):  
Guang Jun Liu ◽  
T. Jiang ◽  
Q.K. Jiang ◽  
A.L. Wang
Keyword(s):  
Resonant Frequency ◽  
Temperature Compensation ◽  
Environmental Temperature ◽  
Great Influence ◽  
Temperature Fluctuations ◽  
Actual Performance ◽  
Mems Accelerometer ◽  
Vibration Equation ◽  
Effects Of Temperature

This paper investigates the effects of environmental temperature fluctuations on the performance of a MEMS accelerometer. The model, vibration equation, and calculation of the output of detection capacitance for the accelerometer are presented. The fluctuations in temperature are considered when evaluating the actual performance of the device. The analysis results show that temperature fluctuations have a great influence on the output of the accelerometer although it has little influence on the resonant frequency of sensing mode and the sensitivity of detection capacitance. The performance deviations under the effects of temperature fluctuations are calculated accurately, which provides a reference for the design of temperature compensation method and robust design for the accelerometer.

scholarly journals Temperature Compensation Method for Raster Projectors Used in 3D Structured Light Scanners

Sensors ◽  
2020 ◽  
Vol 20 (20) ◽  
pp. 5778
Author(s):  
Marcin Adamczyk
Keyword(s):  
Thermal Effects ◽  
Temperature Compensation ◽  
Measurement Method ◽  
Environmental Temperature ◽  
Structured Light ◽  
Three Dimensional ◽  
Compensation Method ◽  
Effect Of Temperature ◽  
Significant Deterioration ◽  
Effects Of Temperature

Raster projectors are commonly used in many various measurement applications where active lighting is required, such as in three-dimensional structured light scanners. The effect of temperature on the raster projector, in some conditions, can lead to significant deterioration of the measurements performed with such a scanner. In this paper, the outcomes of several experiments concerning the effects of temperature on raster projectors are presented. The described research is focused on the thermal deformations of projected images caused by common thermal effects observed in projectors: those caused by the warming-up process and changes in ambient environmental temperature. A software compensation method is also presented. It is suitable for implementation in any existing measurement method that uses raster projectors. The results of performed verification experiments show that the developed compensation method can decrease the thermal drift of the projected images by up to 14 times in the ambient temperature range 14–42 °C.

scholarly journals Pretreatment of Switchgrass for Production of Glucose via Sulfonic Acid-Impregnated Activated Carbon

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 504
Author(s):  
Yane Ansanay ◽  
Praveen Kolar ◽  
Ratna Sharma-Shivappa ◽  
Jay Cheng ◽  
Consuelo Arellano
Keyword(s):  
Activated Carbon ◽  
Sulfonic Acid ◽  
Solid Acid ◽  
Methanesulfonic Acid ◽  
Biofuel Production ◽  
Acid Catalysts ◽  
Effects Of Temperature ◽  
Carbon Catalysts ◽  
Hydrolysis Of

In the present research, activated carbon-supported sulfonic acid catalysts were synthesized and tested as pretreatment agents for the conversion of switchgrass into glucose. The catalysts were synthesized by reacting sulfuric acid, methanesulfonic acid, and p-toluenesulfonic acid with activated carbon. The characterization of catalysts suggested an increase in surface acidities, while surface area and pore volumes decreased because of sulfonation. Batch experiments were performed in 125 mL serum bottles to investigate the effects of temperature (30, 60, and 90 °C), reaction time (90 and 120 min) on the yields of glucose. Enzymatic hydrolysis of pretreated switchgrass using Ctec2 yielded up to 57.13% glucose. Durability tests indicated that sulfonic solid-impregnated carbon catalysts were able to maintain activity even after three cycles. From the results obtained, the solid acid catalysts appear to serve as effective pretreatment agents and can potentially reduce the use of conventional liquid acids and bases in biomass-into-biofuel production.

scholarly journals Complex Permittivity Characterization of Liquid Samples Based on a Split Ring Resonator (SRR)

Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3385
Author(s):  
Jialu Ma ◽  
Jingchao Tang ◽  
Kaicheng Wang ◽  
Lianghao Guo ◽  
Yubin Gong ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Complex Permittivity ◽  
Ring Resonator ◽  
High Sensitivity ◽  
Split Ring Resonator ◽  
Debye Model ◽  
Split Ring ◽  
Liquid Samples ◽  
Microwave Sensor

A complex permittivity characterization method for liquid samples has been proposed. The measurement is carried out based on a self-designed microwave sensor with a split ring resonator (SRR), the unload resonant frequency of which is 5.05 GHz. The liquid samples in capillary are placed in the resonant zone of the fabricated senor for high sensitivity measurement. The frequency shift of 58.7 MHz is achieved when the capillary is filled with ethanol, corresponding a sensitivity of 97.46 MHz/μL. The complex permittivity of methanol, ethanol, isopropanol (IPA) and deionized water at the resonant frequency are measured and calibrated by the first order Debye model. Then, the complex permittivity of different concentrations of aqueous solutions of these materials are measured by using the calibrated sensor system. The results show that the proposed sensor has high sensitivity and accuracy in measuring the complex permittivity of liquid samples with volumes as small as 0.13 μL. It provides a useful reference for the complex permittivity characterization of small amount of liquid chemical samples. In addition, the characterization of an important biological sample (inositol) is carried out by using the proposed sensor.

Design of Ultrasonic Ranging Circuit Based on STC Microcontroller

2013 ◽  
Vol 722 ◽  
pp. 59-63
Author(s):  
Rui Luo ◽  
Zi Hong Zhang
Keyword(s):  
System Performance ◽  
Temperature Compensation ◽  
Measurement Accuracy ◽  
Environmental Temperature ◽  
Detection Distance ◽  
Compensation Circuit ◽  
High Measurement ◽  
Ultrasonic Ranging ◽  
Allowable Range ◽  
Market Promotion

In this paper, based on the 18B20 temperature compensation circuit for ultrasonic ranging circuit, can eliminate the influence of environmental temperature on ultrasonic velocity, this paper introduced the ultrasonic ranging system, the system includes ultrasonic transmitting circuit, receiving circuit and display circuit, the results of the experiment show that, the system detection distance can be up to 12M, the error is in the allowable range, the range finder the system performance is stable, high measurement accuracy, distance, has a certain practicality and market promotion value.

scholarly journals CARACTERIZAÇÕES ANATÔMICA E FÍSICO-MECÂNICA DA MADEIRA DE Liquidambar sp.

FLORESTA ◽  
2015 ◽  
Vol 45 (4) ◽  
pp. 723 ◽  
Author(s):  
Thaís Pereira Freitas ◽  
Lairo David Feuchard ◽  
José Tarcísio Silva Oliveira ◽  
Juarez Benigno Paes ◽  
Marina Donária Chaves Arantes
Keyword(s):  
Specific Gravity ◽  
Dimensional Stability ◽  
Mechanical Characterization ◽  
Great Influence ◽  
Low Frequency ◽  
Ground Level ◽  
Espírito Santo ◽  
Vessel Elements ◽  
Espirito Santo

Este trabalho teve como objetivo a caracterização anatômica e físico-mecânica da madeira de Liquidambar sp. Para tanto, foram utilizadas três árvores com oito anos de idade, provenientes de um arboreto localizado do município de Guaçuí, Espírito Santo. As características anatômicas analisadas foram as dimensões das fibras (comprimento, diâmetro total e do lume e espessura da parede), dos elementos de vasos (diâmetro tangencial e frequência) e dos raios (altura, largura e frequência). Para a caracterização físico-mecânica foram avaliadas a massa específica (básica, aparente a 12% de umidade e anidra), as contrações totais lineares e volumétrica, a resistência à flexão estática, à compressão paralela às fibras, ao cisalhamento e dureza Janka. Constatou-se frequência vascular numerosa com vasos de pequeno diâmetro tangencial, raios heterocelulares ocorrendo em baixa frequência, e fibras libriformes longas de paredes delgadas a espessas. A massa específica básica da madeira proveniente de discos retirados a 1,30 m do nível do solo foi de 0,48 g cm-3, sendo considerada média, a estabilidade dimensional foi considerada baixa, e houve grande influência da umidade nos valores de resistência da madeira. AbstractAnatomical and physical-mechanical characterization of Liquidambar sp. wood. This research aimed to improve anatomical, physical and mechanical characterization of Liquidambar sp.wood. Three trees were obtained, at eight years of age, from an arboretum located in Guaçuí, Espírito Santo State, Brazil. The analyzed variables were dimensions of the fibers (length, total diameter and diameter of the lumen and wall thickness), the vessel elements (tangential diameter and frequency), and ray (height, width and frequency). The specific gravity (basic, at 12% moisture content and dry), and total volumetric and linear shrinkages, resistance to bending, compression parallel to the fibers, shear and Janka hardness. For anatomical description it was found numerous vessels often with small tangential diameter, heterocellular rays occurring at low frequency, and long libriform fibers with thick to thin walls. The specific gravity of wood from disks taken at 1.30 m from ground level was 0.48 g cm-3, wich we considered average, the dimensional stability was low, and there was great influence of moisture in the resistance values in wood.Keywords: Anatomy; specific gravity; dimensional stability; mechanical strength.

scholarly journals Detection and molecular characterization of Pepper mild mottle virus in Serbia

Genetika ◽  
2015 ◽  
Vol 47 (2) ◽  
pp. 651-663 ◽  
Author(s):  
Dragana Milosevic ◽  
Ivana Stankovic ◽  
Aleksandra Bulajic ◽  
Maja Ignjatov ◽  
Zorica Nikolic ◽  
...  
Keyword(s):  
Mosaic Virus ◽  
Molecular Characterization ◽  
Great Influence ◽  
Alfalfa Mosaic Virus ◽  
Resistance Breeding ◽  
Elisa Test ◽  
Mottle Virus ◽  
Pepper Mild Mottle Virus ◽  
Das Elisa

During 2009 and 2010, a survey was conducted in pepper crops to detect the possible presence of Pepper mild mottle virus (PMMoV) in Serbia. A total of 239 pepper samples from 39 crops at 26 localities were collected and analyzed for the presence of PMMoV, Cucumber mosaic virus (CMV), Potato virus Y (PVY), and Alfalfa mosaic virus (AMV), using DAS-ELISA test. Although it was detected in a small percentage, PMMoV could pose a threat to pepper production in Serbia due to its rapid seed-borne spread. Presence of PMMoV was confirmed by serological and biological detection, followed by conventional reverse transcription RT-PCR, using primers specific for the RNA-dependent RNA polymerase (RdRp) and the coat protein (CP) genes. Molecular identification confirmed that the Serbian isolates belong to PMMoV pathotypes P1,2 which do not break the resistance gene L3. Reconstructed phylogenetic tree confirmed the allocation of the Serbian isolates together with the majority of PMMoV isolates which belong to pathotypes P1,2. This study represents the first serological and molecular characterization of PMMoV infection of pepper in Serbia, and provides important data on the population structure. The obtained data could have great influence on pepper production in Serbia as well as future pepper resistance breeding in the country.

scholarly journals The right of the stronger: The play Sisyphus and critias

Balcanica ◽  
2004 ◽  
pp. 51-70
Author(s):  
Ivan Jordovic
Keyword(s):  
Great Influence ◽  
Negative Influence ◽  
Human Society ◽  
Law And Order ◽  
Family Ties ◽  
The Third ◽  
The Individual ◽  
The Right ◽  
Constant Interest

The Focus of this study is the standpoint of the play Sisyphus and critias the leader of the thirty towards the right of the stronger. this is a question of constant interest in scientific circles, since its answer can serve as the indicator of the influence this famous theory has had. this interest has been encouraged by the fact that critias? authorship of the play is questionable. however, the question of the author is not of primary importance for this article, because there are some arguments, among some well known ones, which were not considered and which Show that in this satire, regardless of the author and the purpose of this fragment, the right of the stronger is actually non-existant. the first argument to support this theory is that nomosphysis antithesis is nowhere explicitly mentioned although it is the crucial element of the right of the stronger. in addition there is no claim in the play that the exploitation of the strong by the week or by law accrued. the second argument is that despite the incapability of laws to prevent the secret injustice, they and their importance for the human society are depicted in a positive light. it should also be noted that, unlike callicles and glaucon, laws are created to stop the bad and not the good. the third argument is that the invention of religion is accepted as a positive achievement, which finally enables the overcoming of primeval times and lawlessness. the reflection of this argument is a positive characterization of the individual who invented the fear of gods. the fourth argument, which has not been taken into consideration so far is the way the supporters and opponents of lawlessness are described and marked as ????? and ?????? in the satire only physically strong are considered as strong as opposed to callicles, where they are also spiritually superior. intelectually superior in Sisyphus is the inventor of the fear of gods who is also in favor of law and order. the fact that the strong are described as kako? while the supporter of law are recognized as ?????? is also of great importance. in other words, this division re?ects strong influence of aristocratic set of values by which the ?????? are in every way superior to the ?????. some other indications Show that critias cannot be listed as a advocate of the right of the stronger regardless of our previous conclusion about the play. we need to bear in mind the fact that critias has only recently been linked with the theory of the right of the stronger. in the classical period there had been non attempt to explain his ruthless politics in Athens 404/403 BC by Means of the right of the stronger. what is more, no indication that he supported this theory were found. unlike xenophon and philostratus, it is very likely that Plato and Aristotle were mild to critias Due to his family ties with Plato and his friendship with Socrates. however, all the four of them would have stated that critias was an upholder of the right of the stronger if he had actually been that. that way Socrates would have been completely acquitted of the responsibility for the crimes critias had committed, because of the possible assertion that critias was misled by this theory and succumbed to the negative influence of the sophistic teachings. based on these arguments we can conclude that there is no trace of the right of the stronger in the play Sisyphus and that critias did not support this theory. this satirical play and critias were Most probably under a great influence of aristocratic beliefs, which were often scientifically misinterpreted as the reflection of the right of the stronger.

scholarly journals A Geometrical Study on the Roof Tile-Shaped Modes in AlN-Based Piezoelectric Microcantilevers as Viscosity–Density Sensors

Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 658 ◽  
Author(s):  
Víctor Ruiz-Díez ◽  
Javier Toledo ◽  
Jorge Hernando-García ◽  
Abdallah Ababneh ◽  
Helmut Seidel ◽  
...  
Keyword(s):  
Resonant Frequency ◽  
Quality Factor ◽  
Q Factor ◽  
Liquid Media ◽  
Roof Tile ◽  
Aln Film ◽  
Monitoring Applications ◽  
Media Monitoring ◽  
Comprehensive Study

Cantilever resonators based on the roof tile-shaped modes have recently demonstrated their suitability for liquid media monitoring applications. The early studies have shown that certain combinations of dimensions and order of the mode can maximize the Q-factor, what might suggest a competition between two mechanisms of losses with different geometrical dependence. To provide more insight, a comprehensive study of the Q-factor and the resonant frequency of these modes in microcantilever resonators with lengths and widths between 250 and 3000 µm and thicknesses between 10 and 60 µm is presented. These modes can be efficiently excited by a thin piezoelectric AlN film and a properly designed top electrode layout. The electrical and optical characterization of the resonators are performed in liquid media and then their performance is evaluated in terms of quality factor and resonant frequency. A quality factor as high as 140 was measured in isopropanol for a 1000 × 900 × 10 µm3 cantilever oscillating in the 11th order roof tile-shaped mode at 4 MHz; density and viscosity resolutions of 10−6 g/mL and 10−4 mPa·s, respectively are estimated for a geometrically optimized cantilever resonating below 1 MHz.

Sign in / Sign up

Export Citation Format

Share Document