On the Effects of Temperature and Relative Humidity on the Response of a MEMS Arch Resonator

2017 ◽  
Author(s):  
Mohammad H. Hasan ◽  
Hassen M. Ouakad ◽  
Fadi Alsaleem
Keyword(s):  
Relative Humidity ◽  
Frequency Shift ◽  
Natural Frequency ◽  
Natural Frequencies ◽  
Thermal Conditions ◽  
Internal Stresses ◽  
Comprehensive Model ◽  
Temperature And Humidity ◽  
Curved Microbeam ◽  
Effects Of Temperature

In this paper, we present a comprehensive model to simulate the behavior of a general MEMS arch resonator under various thermal conditions. The model takes into account the changes in the microbeam’s parameters, air properties and the internal stresses due to temperature and humidity. The continuous, flexible, initially curved microbeam was excited linearly and nonlinearly around both its first and third modal natural frequencies. It was found that the mutual effects of temperature and humidity on air viscosity is amplified over four times when the microbeam is operated in the nonlinear regime. Furthermore, results showed that the relative humidity influence is more severe at higher values of the temperature. Finally, the microbeam’s frequency shift due to change in humidity increases when operating the microbeam at its third natural frequency compared to first natural frequency.

scholarly journals The Effect of Temperature and Humidity May Reduce the Growth Rate of the Coronavirus Disease 2019 Epidemic

2020 ◽  
Author(s):  
Lei Qin ◽  
Qiang Sun ◽  
Jiani Shao ◽  
Yang Chen ◽  
Xiaomei Zhang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Relative Humidity ◽  
Effect Of Temperature ◽  
Average Temperature ◽  
Temperature And Humidity ◽  
Scatter Plots ◽  
Low Humidity ◽  
Average Relative Humidity ◽  
Effects Of Temperature ◽  
The Relationship

Abstract Background: The effects of temperature and humidity on the epidemic growth of coronavirus disease 2019 (COVID-19)remains unclear.Methods: Daily scatter plots between the epidemic growth rate (GR) and average temperature (AT) or average relative humidity (ARH) were presented with curve fitting through the “loess” method. The heterogeneity across days and provinces were calculated to assess the necessity of using a longitudinal model. Fixed effect models with polynomial terms were developed to quantify the relationship between variations in the GR and AT or ARH.Results: An increased AT dramatically reduced the GR when the AT was lower than −5°C, the GR was moderately reduced when the AT ranged from −5°C to 15°C, and the GR increased when the AT exceeded 15°C. An increasedARH increased theGR when the ARH was lower than 72% and reduced theGR when the ARH exceeded 72%.Conclusions: High temperatures and low humidity may reduce the GR of the COVID-19 epidemic. The temperature and humidity curves were not linearly associated with the COVID-19 GR.

Influence of Mixing Environmental Conditions on Flowability of Lactose Blends

2014 ◽  
Vol 633 ◽  
pp. 3-6 ◽  
Author(s):  
Xiang Yun Lu ◽  
Lan Chen ◽  
Rui Lin Heng ◽  
Yun Zhang Cheng ◽  
Umezuruike Linus Opara
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Environmental Temperature ◽  
Dry Powder ◽  
Temperature And Humidity ◽  
Powder Flowability ◽  
Higher Temperature ◽  
Effects Of Temperature

Powder flowability is one of the most important properties affecting the filling and delivering processes of dry powder inhalations. When the powder is exposed to different environmental (temperature, relative humidity (RH)) conditions, the interaction between particulates would influence the flowability of powders. Blends of 83% coarse lactose (D50=126μm) and 17% fine lactose (D50= 7μm) were prepared at three different mixing environments and the effects of temperature and humidity on powder flowability were investigated. Results indicated that mixing under relatively higher temperature and lower RH environmental conditions improved the flowability of lactose blends.

Effect of Temperature and Humidity on Measuring Ionization Current Inside Contaminated Pipes

2013 ◽  
Author(s):  
Pingchuan Li ◽  
Xianguo Tuo ◽  
Mingzhe Liu ◽  
Jun Ren ◽  
Qibiao Wang ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Long Range ◽  
Regression Method ◽  
Experimental Results ◽  
Ion Current ◽  
Effect Of Temperature ◽  
Multiple Regression Method ◽  
Temperature And Humidity ◽  
Different Temperatures ◽  
Effects Of Temperature

This paper reported the experimental results of ion current under different temperatures and relative humidity using long range alpha detector (LRAD). An approximation relation between the measuring values, temperatures and relative humidity has been obtained using the linear multiple regression method. The experimental results have shown that the measuring values decrease with the increase of temperature and humidity. The influence of humidity on results outweighs that of temperatures. And both temperature and humidity are obviously negative correlated with measured values. Further experiments will be performed to confirm the coupling effects of temperature and humidity and reported later.

AN APPARATUS FOR DETERMINING THE EFFECTS OF TEMPERATURE AND HUMIDITY ON GERMINATION OF FUNGOUS SPORES

1955 ◽  
Vol 33 (4) ◽  
pp. 289-292 ◽  
Author(s):  
Mary P. Hart ◽  
Donald M. MacLeod
Keyword(s):  
Relative Humidity ◽  
Beauveria Bassiana ◽  
Temperature And Humidity ◽  
Petri Dishes ◽  
Effects Of Temperature ◽  
Microscope Slides

An apparatus is described by which fungous spores can be uniformly distributed on microscope slides. A procedure is outlined whereby Petri dishes can be converted into airtight humidity chambers, the humidity of which can be readily checked. It was found that above 94% relative humidity maximum germination among Beauveria bassiana spores occurs at 28 °C.

EFFECTS OF TEMPERATURE AND HUMIDITY ON POLLEN VIABILITY OF SIX ROSE SPECIES

1976 ◽  
Vol 56 (3) ◽  
pp. 517-523 ◽  
Author(s):  
M. KHOSH-KHUI ◽  
A. BASSIRI ◽  
M. NIKNEJAD
Keyword(s):  
Relative Humidity ◽  
Significant Interaction ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Pollen Storage ◽  
Viable Pollen ◽  
Temperature And Humidity ◽  
Effects Of Temperature ◽  
Partial Vacuum ◽  
Relative Humidity Data

Pollen of six species of genus Rosa was stored under partial vacuum at 0 and 25 C and 10, 30, 50, 70 and 90% relative humidity. Data obtained showed significant interaction between temperature and humidity. The best conditions for pollen storage at 0 C were 50 and 70% relative humidity, while at 25 C, the best humidity was 30 and 50%, respectively. Most species reached the highest percentage of viable pollen in 2–3 wk of storage. It was concluded that for short periods of pollen storage, 25 C was more suitable than 0 C for rose pollen. Differences among responses of Rosa pollen grains to storage environment are discussed.

scholarly journals The Effect Of Outside Corridor’s Orientation to Interior Thermal Condition at Lawang Sewu Semarang.

2018 ◽  
Vol 73 ◽  
pp. 01011
Author(s):  
Benediktus Yosef Arya Wastunimpuna ◽  
Wahyu Setia Budi ◽  
Erni Setyowati
Keyword(s):  
Heat Stress ◽  
Relative Humidity ◽  
Thermal Condition ◽  
Natural Ventilation ◽  
Thermal Conditions ◽  
Standard Theory ◽  
Hot Wire ◽  
Air Movement ◽  
Dutch Colonial

The outside corridor of Dutch Colonial Building in Indonesia was made to make the temperature of the room more comfortable. Lawang Sewu Building in Semarang is one example of a building that has an outside corridor along the building and until now still use natural ventilation. This study focuses on finding out whether there is a difference on the thermal conditions of each room’s orientation, so after that we know the effect of orientation of the outdoor corridor to the temperature of the interior. In this study the experiment based on measurement using Heat Stress WBGT Meter for Wet Bulb Temperature, Dry Bulb Temperature, Relative Humidity, and KW0600653 Hot Wire Anemometer for the air movement. The data will be analysed using thermal standard theory to find out which point has the most comfortable thermal conditions.. At the end of this study will be found the effect of corridor’s orientation to thermal condition of the interior in Lawang Sewu Semarang.

scholarly journals Effects of Elliptical Hole on the Correlation of Natural Frequency with Buckling Load of Basalt Laminates Composite Plates

2020 ◽  
Vol 27 (1) ◽  
pp. 216-225
Author(s):  
Buntheng Chhorn ◽  
WooYoung Jung
Keyword(s):  
Free Vibration ◽  
Natural Frequency ◽  
Natural Frequencies ◽  
Basalt Fiber ◽  
Orientation Angle ◽  
Elliptical Hole ◽  
Composite Plates ◽  
Buckling Load ◽  
Mode Shapes ◽  
Geometric Ratio

AbstractRecently, basalt fiber reinforced polymer (BFRP) is acknowledged as an outstanding material for the strengthening of existing concrete structure, especially it was being used in marine vehicles, aerospace, automotive and nuclear engineering. Most of the structures were subjected to severe dynamic loading during their service life that may induce vibration of the structures. However, free vibration studied on the basalt laminates composite plates with elliptical cut-out and correlation of natural frequency with buckling load has been very limited. Therefore, effects of the elliptical hole on the natural frequency of basalt/epoxy composite plates was performed in this study. Effects of stacking sequence (θ), elliptical hole inclination (ϕ), hole geometric ratio (a/b) and position of the elliptical hole were considered. The numerical modeling of free vibration analysis was based on the mechanical properties of BFRP obtained from the experiment. The natural frequencies as well as mode shapes of basalt laminates composite plates were numerically determined using the commercial program software (ABAQUS). Then, the determination of correlation of natural frequencies with buckling load was carried out. Results showed that elliptical hole inclination and fiber orientation angle induced the inverse proportion between natural frequency and buckling load.

scholarly journals A Vibration-Based Structural Health Monitoring System for Transmission Line Towers

Electronics ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 515 ◽  
Author(s):  
Long Zhao ◽  
Xinbo Huang ◽  
Ye Zhang ◽  
Yi Tian ◽  
Yu Zhao
Keyword(s):  
Structural Health Monitoring ◽  
Transmission Line ◽  
Natural Frequency ◽  
Health Monitoring ◽  
Structural Changes ◽  
Natural Frequencies ◽  
Transmission Tower ◽  
Health Monitoring System ◽  
Wind Speeds ◽  
Before And After

In this paper, we present a vibration-based transmission tower structural health monitoring system consisting of two parts that identifies structural changes in towers. An accelerometer group realizes vibration response acquisition at different positions and reduces the risk of data loss by data compression technology. A solar cell provides the power supply. An analyser receives the data from the acceleration sensor group and calculates the transmission tower natural frequencies, and the change in the structure is determined based on natural frequencies. Then, the data are sent to the monitoring center. Furthermore, analysis of the vibration signal and the calculation method of natural frequencies are proposed. The response and natural frequencies of vibration at different wind speeds are analysed by time-domain signal, power spectral density (PSD), root mean square (RMS) and short-time Fouier transform (STFT). The natural frequency identification of the overall structure by the stochastic subspace identification (SSI) method reveals that the number of natural frequencies that can be calculated at different wind speeds is different, but the 2nd, 3rd and 4th natural frequencies can be excited. Finally, the system was tested on a 110 kV experimental transmission line. After 18 h of experimentation, the natural frequency of the overall structure of the transmission tower was determined before and after the tower leg was lifted. The results show that before and after the tower leg is lifted, the natural frequencies of each order exhibit obvious changes, and the differences in the average values can be used as the basis for judging the structural changes of the tower.

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