Design, Modeling and Simulation of CMOS-MEMS Piezoresistive Cantilever Based Carbon Dioxide Gas Sensor for Capnometry

2011 ◽  
Vol 403-408 ◽  
pp. 3769-3774 ◽  
Author(s):  
Asif Mirza ◽  
Nor Hisham Hamid ◽  
Mohd Haris Md Khir ◽  
Khalid Ashraf ◽  
M.T. Jan ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Modeling And Simulation ◽  
Low Cost ◽  
Cmos Technology ◽  
Simulation Software ◽  
Dynamic Mode ◽  
Fully Differential ◽  
Carbon Dioxide Gas ◽  
Carbon Dioxide Co2 ◽  
Relative Change

This paper reports design, modeling and simulation of MEMS based sensor working in dynamic mode with fully differential piezoresistive sensing for monitoring the concentration of exhaled carbon dioxide (CO2) gas in human breath called capnometer. CO2 being a very important biomarker, it is desirable to extend the scope of its monitoring beyond clinical use to home and ambulatory services. Currently the scope of capnometers and its adaption is limited by high cost, large size and high power consumption of conventional capnometers . In recent years, MEMS based micro resonant sensors have received considerable attention due to their potential as a platform for the development of many novel physical, chemical, and biological sensors with small size, low cost and low power requirements. The sensor is designed using 0.35 micron CMOS technology. CoventorWare and MATLAB have been used as simulation software. According to the developed model and simulation results the resonator has resonant frequency 57393 Hz and mass sensitivity of 3.2 Hz/ng. The results show that the longitudinal relative change of resistance is 0.24%/µm while the transverse relative change of resistance is -0.03%/µm.

scholarly journals Comparing the Use of High- to Low-Cost Black Carbon and Carbon Dioxide Sensors for Characterizing On-Road Diesel Truck Emissions

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6714
Author(s):  
Rebecca A. Sugrue ◽  
Chelsea V. Preble ◽  
Thomas W. Kirchstetter
Keyword(s):  
Carbon Dioxide ◽  
Black Carbon ◽  
Emission Factor ◽  
Lower Cost ◽  
Low Cost ◽  
Ambient Air ◽  
Source Characterization ◽  
Ambient Conditions ◽  
Heavy Duty Diesel ◽  
Carbon Dioxide Co2

The exhaust plume capture method is a commonly used approach to measure pollutants emitted by in-use heavy-duty diesel trucks. Lower cost sensors, if used in place of traditional research-grade analyzers, could enable wider application of this method, including use as a monitoring tool to identify high-emitting trucks that may warrant inspection and maintenance. However, low-cost sensors have for the most part only been evaluated under ambient conditions as opposed to source-influenced environments with rapidly changing pollutant concentrations. This study compared black carbon (BC) emission factors determined using different BC and carbon dioxide (CO2) sensors that range in cost from $200 to $20,000. Controlled laboratory experiments show that traditional zero and span steady-state calibration checks are not robust indicators of sensor performance when sampling short duration concentration peaks. Fleet BC emission factor distributions measured at two locations at the Port of Oakland in California with 16 BC/CO2 sensor pairs were similar, but unique sensor pairs identified different high-emitting trucks. At one location, the low-cost PP Systems SBA-5 agreed on the classification of 90% of the high emitters identified by the LI-COR LI-7000 when both were paired with the Magee Scientific AE33. Conversely, lower cost BC sensors when paired with the LI-7000 misclassified more than 50% of high emitters when compared to the AE33/LI-7000. Confidence in emission factor quantification and high-emitter identification improves with larger integrated peak areas of CO2 and especially BC. This work highlights that sensor evaluation should be conducted under application-specific conditions, whether that be for ambient air monitoring or source characterization.

S. I. Engine Pollution Control Using Low-Cost Palletized Catalytic Converter

Volume 2 ◽  
2004 ◽  
Author(s):  
Madhuri Jakkaraju ◽  
Vasudha Patri
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Pollution Control ◽  
Noble Metals ◽  
Fossil Fuel ◽  
Catalytic Converter ◽  
Low Cost ◽  
Hydrocarbon Emissions ◽  
Oxides Of Nitrogen ◽  
Carbon Dioxide Co2

I. C. Engines consume large amounts of fossil fuel emitting harmful pollutants like carbon monoxide (CO), unburnt hydrocarbons (UBHC), and oxides of nitrogen (NOx). By using a catalytic converter (CC), the carbon monoxide, hydrocarbon emissions can be transformed into less harmful carbon dioxide (CO2) & water vapor (H2O). Currently available CC’s are using costly noble metals like platinum (pt), palladium (pd), rhodium (rh) etc., hence making them expensive. This paper deals with the use of low-cost palletized silver coated alumina as the catalyst element in a CC. In this study, alumina and silver were used in the ratio of 10:1. All tests have been conducted on a stationary S.I. Engine at a constant speed of 1500 r.p.m with and without CC. Also, the performance of the palletized CC in combination with promoters like Bismuth, Cerium and Lanthanum was tested which have shown better results than silver alone as the coating element. It has been experimentally determined that the CO emissions have dropped from 7.25 (% vol) to 3.03(% vol) and the HC values have reduced from 350 ppm to 190 ppm.

scholarly journals A low-voltage CMOS current-mode incremental signaling scheme for high-speed parallel links

2021 ◽  
Author(s):  
Tao Wang
Keyword(s):  
High Speed ◽  
Low Voltage ◽  
Low Cost ◽  
Current Mode ◽  
Cmos Technology ◽  
Fully Differential ◽  
Parallel Links ◽  
Data Links ◽  
Parallel Data ◽  
The Cost

Point-to-point parallel links are widly used in short-distance high-speed data communications. For these links, the design goal is not only to integrate a large number of I/Os in the systems, but also to increase the bit rate per I/O. The cost per I/O has to be kept low as performance improves. Voltage and timing error sources limit the performance of data links and affect its robustnest. These kinds of noise impose greater challenges in parallel data links, such as inter-signal timing skew and inter-signal cross-talk. The use of low-cost schemes, such as single-ended signaling, is effected signaficantly [sic] by the voltage and timging [sic] noise. Fully differential signaling schemes, two physical paths per signal channel, significantly increases the cost of system. Therefore, overcoming the voltage noise, keeping the cost low are two challenges in high-speed parallel links. In this thesis, we propose a new current-mode signaling scheme current-mode incremtnal [sic] signaling for high-speed parallel links. Also, the circuits of the receiver called current-integrating receiver are presented. To assess the effectiveness of the proposed signaling scheme, a 4-bit parallel link consisting of four bipolar current-mode drivers, five 10 cm microstrip lines with a FR4 substrate, and four proposed current-integrating receivers is implemented in UMC 0.13[micro]m, 1.2V CMOS technology and analyzed using SpectreRF from Cadence Design Systems with BSIM3V3 device models. Simulation results demonstrate that the proposed current-mode incremental signaling scheme and the current-integrating receiver are capable of transmitting parallel data at 2.5 Gbyte/s.

Carbon Dioxide Gas Sensor Using SAW Device Based on ZnO Film

2011 ◽  
Vol 135-136 ◽  
pp. 347-352 ◽  
Author(s):  
Chang Bao Wen ◽  
Yong Feng Ju ◽  
Wan Lin Li ◽  
Wen Zheng Sun ◽  
Xin Xu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Gas Sensor ◽  
Side Lobe ◽  
Center Frequency ◽  
Zno Film ◽  
Co2 Gas ◽  
Response Characteristics ◽  
Carbon Dioxide Gas ◽  
Co2 Gas Sensor ◽  
Carbon Dioxide Co2

Carbon dioxide (CO2) gas sensor using surface acoustic wave (SAW) device based on Zinc oxide (ZnO) was developed and fabricated in this paper. The center frequency of SAW device is 203.528 MHz. The input and two output interdigital transducers (IDT) apodized by Morlet wavelet function can improve the side lobe rejection compared with uniform IDT. The ZnO film sensitive to CO2 gas was fabricated in measurement acoustic track of SAW device. Experiments results confirm that the CO2 gas sensor using SAW device based on ZnO film has good response characteristics to different concentrations CO2 gas. Furthermore, the CO2 gas sensor using SAW device based on ZnO film has good stability and linearity.

scholarly journals MAKING LEARNING MEDIA FOR GREENBOX EFFECT SIMULATOR TO IMPROVE UNDERSTANDING OF THE CONCEPT OF THE GREENHOUSE EFFECT

2021 ◽  
Vol 5 (1) ◽  
pp. 11-16
Author(s):  
Noer Sarifah Ainy ◽  
Nestiyanto Hadi
Keyword(s):  
Carbon Dioxide ◽  
Global Warming ◽  
Greenhouse Gases ◽  
Air Temperature ◽  
Greenhouse Effect ◽  
Independent Variables ◽  
Carbon Dioxide Gas ◽  
The Earth ◽  
Yellow Color ◽  
Carbon Dioxide Co2

The earth is experiencing global warming due to an increase in air temperature (greenhouse effect). This is due to the large number of greenhouse gases produced by human activities. In addition, it is also due to the reduced number of plants that absorb greenhouse gases, especially carbon dioxide. This condition causes the study of the greenhouse effect to become an object studied by students at school. Understanding the greenhouse effect is somewhat difficult if only understood in theory. Increasing understanding can be done by making practicum learning media. This study aims to create learning media for the Greenbox Effect Simulator to help understand the concept of the greenhouse effect. The research was conducted using control variables and independent variables (use of plants and without plants). The plants used are Caisim, Sri Gading and Anggrek. The presence of carbon dioxide (CO2) greenhouse gases can be detected by three things, namely changes in the color of the CO2 indicator, changes in temperature, and visibility of the box. The color of the CO2 indicator shows green and green yellow for Box B (with plants) which means the concentration of CO2 in normal conditions. Whereas Box C (without plants) gives a yellow color, which means that the concentration of CO2 is at high conditions. The presence of carbon dioxide gas from combustion will increase the temperature by 1.4 - 1.9 oC in Box C (without plants) and 0.7 - 1.5 oC in Box B (use of plants). The visibility of Box B shows a higher brightness level than Box C. The best plants that can absorb CO2 concentrations are orchids. The ability of orchids to absorb CO2 is assisted by their roots which also function to carry out photosynthesis. The existence of plants functions to absorb CO2 quite well when viewed from changes in temperature, color indicators and visibility.

scholarly journals Correlation of Respiratory Aerosols and Metabolic Carbon Dioxide

2021 ◽  
Vol 13 (21) ◽  
pp. 12203
Author(s):  
Niklas Kappelt ◽  
Hugo Savill Russell ◽  
Szymon Kwiatkowski ◽  
Alireza Afshari ◽  
Matthew Stanley Johnson
Keyword(s):  
Carbon Dioxide ◽  
Oral Fluid ◽  
Low Cost ◽  
Co2 Concentration ◽  
Transmission Route ◽  
Viral Loads ◽  
Co2 Concentrations ◽  
Carbon Dioxide Co2 ◽  
The Individual ◽  
Metabolic Carbon

Respiratory aerosols from breathing and talking are an important transmission route for viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies have found that particles with diameters ranging from 10 nm to 145 μm are produced from different regions in the respiratory system and especially smaller particles can remain airborne for long periods while carrying viral RNA. We present the first study in which respiratory aerosols have been simultaneously measured with carbon dioxide (CO2) to establish the correlation between the two concentrations. CO2 concentrations are easily available through low-cost sensors and could be used to estimate viral exposure through this correlation, whereas source-specific aerosol measurements are complicated and not possible with low-cost sensors. The increase in both respiratory aerosols and CO2 was linear over ten minutes in a 2 m3 chamber for all participants, suggesting a strong correlation. On average, talking released more particles than breathing, with 14,600 ± 16,800 min−1 (one-σ standard deviation) and 6210 ± 5630 min−1 on average, respectively, while CO2 increased with 139 ± 33 ppm min−1 during talking and 143 ± 29 ppm min−1 during breathing. Assuming a typical viral load of 7×106 RNA copies per mL of oral fluid, ten minutes of talking and breathing are estimated to produce 1 and 16 suspended RNA copies, respectively, correlating to a CO2 concentration of around 1800 ppm in a 2 m3 chamber. However, viral loads can vary by several orders of magnitude depending on the stage of the disease and the individual. It was therefore concluded that, by measuring CO2 concentrations, only the number and volume concentrations of released particles can be estimated with reasonable certainty, while the number of suspended RNA copies cannot.

scholarly journals Use of Multiple Low Cost Carbon Dioxide Sensors to Measure Exhaled Breath Distribution with Face Mask Type and Wearing Behaviour

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6204
Author(s):  
Naveed Salman ◽  
Muhammad Waqas Khan ◽  
Michael Lim ◽  
Amir Khan ◽  
Andrew H. Kemp ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Low Cost ◽  
Co2 Concentration ◽  
Face Mask ◽  
Base Station ◽  
Exhaled Breath ◽  
Co2 Sensor ◽  
Improper Use ◽  
The Face ◽  
Carbon Dioxide Co2

The use of cloth face coverings and face masks has become widespread in light of the COVID-19 pandemic. This paper presents a method of using low cost wirelessly connected carbon dioxide (CO2) sensors to measure the effects of properly and improperly worn face masks on the concentration distribution of exhaled breath around the face. Four types of face masks are used in two indoor environment scenarios. CO2 as a proxy for exhaled breath is being measured with the Sensirion SCD30 CO2 sensor, and data are being transferred wirelessly to a base station. The exhaled CO2 is measured in four directions at various distances from the head of the subject, and interpolated to create spatial heat maps of CO2 concentration. Statistical analysis using the Friedman’s analysis of variance (ANOVA) test is carried out to determine the validity of the null hypotheses (i.e., distribution of the CO2 is same) between different experiment conditions. Results suggest CO2 concentrations vary little with the type of mask used; however, improper use of the face mask results in statistically different CO2 spatial distribution of concentration. The use of low cost sensors with a visual interpolation tool could provide an effective method of demonstrating the importance of proper mask wearing to the public.

Carbon Dioxide Sequestered Concrete

2020 ◽  
Vol 12 (9) ◽  
Author(s):  
Nur Liyana Mohd Kamal ◽  
◽  
Zarina Itam ◽  
Yuovendra Sivaganese ◽  
Norizham Abdul Razak ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Construction Industry ◽  
Carbon Footprint ◽  
Human Beings ◽  
Greenhouse Gasses ◽  
Carbon Dioxide Gas ◽  
Compressive Strength Of Concrete ◽  
Mineral Trapping ◽  
Carbon Dioxide Co2 ◽  
The Impact

Carbon dioxide, CO2 accounts for most of the emission from all the types of greenhouse gasses in the world. The ability of CO2 to remain longer than other greenhouse gases and the convenience of producing CO2 has resulted in its high projection in a yearly manner. The prime factor for the emission of CO2 are from the actions of human beings. One such human act is the concrete industry. Total emissions from the concrete industry could therefore contribute as much as 8% of global CO2 emissions. Sequestered CO2 in concrete can provide an impact on reducing the carbon footprint and is also able to improve the compressive strength of concrete. During this process, the sequestered carbon dioxide chemically reacts with cement to produce a mineral, trapping carbon dioxide gas in the concrete. Hence, sequestering carbon dioxide gas in concrete does not only on a bigger scale reduces carbon footprint, but it also reduces the impact the construction industry has on the environment. This paper presents a detailed review on the chemical reaction that takes place during the sequestration of carbon dioxide and the research published on the effects of carbon dioxide sequestered concrete on its properties. The impact this process has on the concrete industry and the environment is discussed in this paper.

scholarly journals A low-voltage CMOS current-mode incremental signaling scheme for high-speed parallel links

2021 ◽  
Author(s):  
Tao Wang
Keyword(s):  
High Speed ◽  
Low Voltage ◽  
Low Cost ◽  
Current Mode ◽  
Cmos Technology ◽  
Fully Differential ◽  
Parallel Links ◽  
Data Links ◽  
Parallel Data ◽  
The Cost

Point-to-point parallel links are widly used in short-distance high-speed data communications. For these links, the design goal is not only to integrate a large number of I/Os in the systems, but also to increase the bit rate per I/O. The cost per I/O has to be kept low as performance improves. Voltage and timing error sources limit the performance of data links and affect its robustnest. These kinds of noise impose greater challenges in parallel data links, such as inter-signal timing skew and inter-signal cross-talk. The use of low-cost schemes, such as single-ended signaling, is effected signaficantly [sic] by the voltage and timging [sic] noise. Fully differential signaling schemes, two physical paths per signal channel, significantly increases the cost of system. Therefore, overcoming the voltage noise, keeping the cost low are two challenges in high-speed parallel links. In this thesis, we propose a new current-mode signaling scheme current-mode incremtnal [sic] signaling for high-speed parallel links. Also, the circuits of the receiver called current-integrating receiver are presented. To assess the effectiveness of the proposed signaling scheme, a 4-bit parallel link consisting of four bipolar current-mode drivers, five 10 cm microstrip lines with a FR4 substrate, and four proposed current-integrating receivers is implemented in UMC 0.13[micro]m, 1.2V CMOS technology and analyzed using SpectreRF from Cadence Design Systems with BSIM3V3 device models. Simulation results demonstrate that the proposed current-mode incremental signaling scheme and the current-integrating receiver are capable of transmitting parallel data at 2.5 Gbyte/s.

Sign in / Sign up

Export Citation Format

Share Document