Enhancement of Imperfection Detection Capabilities in TIG Welding of the Infrared Monitoring System

For a low cost, there are industrial infrared monitoring systems used for imperfection detection and identification in welded joints. The key drawback that impedes real life industrial applications is the low spatial resolution, as well as the temporal resolution of low-cost infrared (IR) cameras. This is also the case in tungsten inert gas (TIG) welding. Taking into consideration the influence of voltage on the arc energy and heat input, high frequency sampled voltage was used to evaluate the interpolated temporal resolution of IR sequences. Additionally, a reflected temperature correction method was proposed to reduce the uncertainty of absolute temperature measurement with a thermographic camera. The proposed method was applied to detect several imperfection types, such as lack of or incomplete penetration as well as incorrect weld shape and size (including burnouts). Results obtained for different interpolation factors were compared. The obtained results emphasize the validity of reflected temperature correction method. For the weld defects detection task, the smallest detectable defect was found for various interpolation factors. Moreover, the correspondence of arc voltage and the joint temperature was checked. Additionally, a set of decision rules was elaborated on and applied to distinguish between various joint conditions. It was found that defects that do not have symmetrical temperature distribution with respect to the joint axis are harder to identify.

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Temperature measurement performance of silicon piezoresistive MEMS pressure sensors for industrial applications

Facta universitatis - series Electronics and Energetics ◽

10.2298/fuee1501123f ◽

2015 ◽

Vol 28 (1) ◽

pp. 123-131 ◽

Cited By ~ 5

Author(s):

Milos Frantlovic ◽

Ivana Jokic ◽

Zarko Lazic ◽

Branko Vukelic ◽

Marko Obradov ◽

...

Keyword(s):

Temperature Measurement ◽

Low Cost ◽

Pressure Sensors ◽

High Sensitivity ◽

Correction Method ◽

Industrial Applications ◽

Sensor Applications ◽

Piezoresistive Pressure Sensors ◽

Mems Pressure Sensors

Temperature and pressure are the most common parameters to be measured and monitored not only in industrial processes but in many other fields from vehicles and healthcare to household appliances. Silicon microelectromechanical (MEMS) piezoresistive pressure sensors are the first and the most successful MEMS sensors, offering high sensitivity, solid-state reliability and small dimensions at a low cost achieved by mass production. The inherent temperature dependence of the output signal of such sensors adversely affects their pressure measurement performance, necessitating the use of correction methods in a majority of cases. However, the same effect can be utilized for temperature measurement, thus enabling new sensor applications. In this paper we perform characterization of MEMS piezoresistive pressure sensors for temperature measurement, propose a sensor correction method, and demonstrate that the measurement error as low as ? 0.3?C can be achieved.

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Extended Joint Sparsity Reconstruction for Spatial and Temporal ERT Imaging

Sensors ◽

10.3390/s18114014 ◽

2018 ◽

Vol 18 (11) ◽

pp. 4014 ◽

Cited By ~ 2

Author(s):

Bo Chen ◽

Juan Abascal ◽

Manuchehr Soleimani

Keyword(s):

Temporal Resolution ◽

High Speed ◽

Low Cost ◽

Control Process ◽

Industrial Applications ◽

High Temporal Resolution ◽

Conductivity Distribution ◽

Dynamic Movement ◽

Wide Range ◽

The Time Domain

Electrical resistance tomography (ERT) is an imaging technique to recover the conductivity distribution with boundary measurements via attached electrodes. There are a wide range of applications using ERT for image reconstruction or parameter calculation due to high speed data collection, low cost, and the advantages of being non-invasive and portable. Although ERT is considered a high temporal resolution method, a temporally regularized method can greatly enhance such a temporal resolution compared to frame-by-frame reconstruction. In some of the cases, especially in the industrial applications, dynamic movement of an object is critical. In practice, it is desirable for monitoring and controlling the dynamic process. ERT can determine the spatial conductivity distribution based on previous work, and ERT potentially shows good performance in exploiting temporal information as well. Many ERT algorithms reconstruct images frame by frame, which is not optimal and would assume that the target is static during collection of each data frame, which is inconsistent with the real case. Although spatiotemporal-based algorithms can account for the temporal effect of dynamic movement and can generate better results, there is not that much work aimed at analyzing the performance in the time domain. In this paper, we discuss the performance of a novel spatiotemporal total variation (STTV) algorithm in both the spatial and temporal domain, and Temporal One-Step Tikhonov-based algorithms were also employed for comparison. The experimental results show that the STTV has a faster response time for temporal variation of the moving object. This robust time response can contribute to a much better control process which is the main aim of the new generation of process tomography systems.

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PyDOSS: An open-source Python-based communicable disease outbreak surveillance system designed and used in a COVID-19 community care facility (Preprint)

10.2196/preprints.21760 ◽

2020 ◽

Author(s):

Andrew Fang ◽

Jonathan Kia-Sheng Phua ◽

Terrence Chiew ◽

Daniel De-Liang Loh ◽

Lincoln Ming Han Liow ◽

...

Keyword(s):

Open Source ◽

Surveillance System ◽

Community Care ◽

Communicable Disease ◽

Low Cost ◽

Real Life ◽

Disease Outbreak ◽

Disease Spread ◽

Healthcare Team ◽

Increased Risk

BACKGROUND During the Coronavirus Disease 2019 (COVID-19) outbreak, community care facilities (CCF) were set up as temporary out-of-hospital isolation facilities to contain the surge of cases in Singapore. Confined living spaces within CCFs posed an increased risk of communicable disease spread among residents. OBJECTIVE This inspired our healthcare team managing a CCF operation to design a low-cost communicable disease outbreak surveillance system (CDOSS). METHODS Our CDOSS was designed with the following considerations: (1) comprehensiveness, (2) efficiency through passive reconnoitering from electronic medical record (EMR) data, (3) ability to provide spatiotemporal insights, (4) low-cost and (5) ease of use. We used Python to develop a lightweight application – Python-based Communicable Disease Outbreak Surveillance System (PyDOSS) – that was able perform syndromic surveillance and fever monitoring. With minimal user actions, its data pipeline would generate daily control charts and geospatial heat maps of cases from raw EMR data and logged vital signs. PyDOSS was successfully implemented as part of our CCF workflow. We also simulated a gastroenteritis (GE) outbreak to test the effectiveness of the system. RESULTS PyDOSS was used throughout the entire duration of operation; the output was reviewed daily by senior management. No disease outbreaks were identified during our medical operation. In the simulated GE outbreak, PyDOSS was able to effectively detect an outbreak within 24 hours and provided information about cluster progression which could aid in contact tracing. The code for a stock version of PyDOSS has been made publicly available. CONCLUSIONS PyDOSS is an effective surveillance system which was successfully implemented in a real-life medical operation. With the system developed using open-source technology and the code made freely available, it significantly reduces the cost of developing and operating CDOSS and may be useful for similar temporary medical operations, or in resource-limited settings.

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Remote Reflectivity Sensor for Industrial Applications

Sensors ◽

10.3390/s21041301 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1301

Author(s):

Federico Cavedo ◽

Parisa Esmaili ◽

Michele Norgia

Keyword(s):

Low Cost ◽

Cost Effective ◽

Industrial Applications ◽

Interference Immunity ◽

Surface Reflection ◽

Measurement Systems ◽

Digital Detector ◽

Reflected Light ◽

Surface Optical ◽

Diffused Light

A low-cost optical reflectivity sensor is proposed in this paper, able to detect the presence of objects or surface optical properties variations, at a distance of up to 20 m. A collimated laser beam is pulsed at 10 kHz, and a synchronous digital detector coherently measures the back-diffused light collected through a 1-inch biconvex lens. The sensor is a cost-effective solution for punctual measurement of the surface reflection at different distances. To enhance the interference immunity, an algorithm based on a double-side digital baseline restorer is proposed and implemented to accurately detect the amplitude of the reflected light. As results show, the sensor is robust against ambient light and shows a strong sensitivity on a wide reflection range. The capability of the proposed sensor was evaluated experimentally for object detection and recognition, in addition to dedicated measurement systems, like remote encoders or keyphasors, realized far from the object to be measured.

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Deconstruction of Lignin: From Enzymes to Microorganisms

Molecules ◽

10.3390/molecules26082299 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2299

Author(s):

Jéssica P. Silva ◽

Alonso R. P. Ticona ◽

Pedro R. V. Hamann ◽

Betania F. Quirino ◽

Eliane F. Noronha

Keyword(s):

Microbial Communities ◽

Metabolic Pathways ◽

Low Cost ◽

Direct Analysis ◽

Industrial Applications ◽

Natural Environments ◽

Lignocellulosic Residues ◽

Complementary Techniques ◽

Plant Polymer ◽

Powerful Strategy

Lignocellulosic residues are low-cost abundant feedstocks that can be used for industrial applications. However, their recalcitrance currently makes lignocellulose use limited. In natural environments, microbial communities can completely deconstruct lignocellulose by synergistic action of a set of enzymes and proteins. Microbial degradation of lignin by fungi, important lignin degraders in nature, has been intensively studied. More recently, bacteria have also been described as able to break down lignin, and to have a central role in recycling this plant polymer. Nevertheless, bacterial deconstruction of lignin has not been fully elucidated yet. Direct analysis of environmental samples using metagenomics, metatranscriptomics, and metaproteomics approaches is a powerful strategy to describe/discover enzymes, metabolic pathways, and microorganisms involved in lignin breakdown. Indeed, the use of these complementary techniques leads to a better understanding of the composition, function, and dynamics of microbial communities involved in lignin deconstruction. We focus on omics approaches and their contribution to the discovery of new enzymes and reactions that impact the development of lignin-based bioprocesses.

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Enhanced catalytic ozonation of ibuprofen using a 3D structured catalyst with MnO2 nanosheets on carbon microfibers

Scientific Reports ◽

10.1038/s41598-021-85651-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Guhankumar Ponnusamy ◽

Hajar Farzaneh ◽

Yongfeng Tong ◽

Jenny Lawler ◽

Zhaoyang Liu ◽

...

Keyword(s):

Removal Efficiency ◽

Active Sites ◽

Low Cost ◽

Three Dimensional ◽

Industrial Applications ◽

Catalytic Ozonation ◽

Heterogeneous Catalytic ◽

Structured Catalyst ◽

Dimensional Network ◽

Carbon Microfibers

AbstractHeterogeneous catalytic ozonation is an effective approach to degrade refractory organic pollutants in water. However, ozonation catalysts with combined merits of high activity, good reusability and low cost for practical industrial applications are still rare. This study aims to develop an efficient, stable and economic ozonation catalyst for the degradation of Ibuprofen, a pharmaceutical compound frequently detected as a refractory pollutant in treated wastewaters. The novel three-dimensional network-structured catalyst, comprising of δ-MnO2 nanosheets grown on woven carbon microfibers (MnO2 nanosheets/carbon microfiber), was synthesized via a facile hydrothermal approach. Catalytic ozonation performance of Ibuprofen removal in water using the new catalyst proves a significant enhancement, where Ibuprofen removal efficiency of close to 90% was achieved with a catalyst loading of 1% (w/v). In contrast, conventional ozonation was only able to achieve 65% removal efficiency under the same operating condition. The enhanced performance with the new catalyst could be attributed to its significantly increased available surface active sites and improved mass transfer of reaction media, as a result of the special surface and structure properties of this new three-dimensional network-structured catalyst. Moreover, the new catalyst displays excellent stability and reusability for ibuprofen degradation over successive reaction cycles. The facile synthesis method and low-cost materials render the new catalyst high potential for industrial scaling up. With the combined advantages of high efficiency, high stability, and low cost, this study sheds new light for industrial applications of ozonation catalysts.

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60–700 K CTAT and PTAT Temperature Sensors with 4H-SiC Schottky Diodes

Sensors ◽

10.3390/s21030942 ◽

2021 ◽

Vol 21 (3) ◽

pp. 942

Author(s):

Razvan Pascu ◽

Gheorghe Pristavu ◽

Gheorghe Brezeanu ◽

Florin Draghici ◽

Philippe Godignon ◽

...

Keyword(s):

Low Cost ◽

Schottky Diodes ◽

Schottky Contact ◽

High Sensitivity ◽

Xrd Analysis ◽

Absolute Temperature ◽

Lower Sensitivity ◽

Readout Circuit ◽

Sensing Element ◽

High Performing

A SiC Schottky dual-diode temperature-sensing element, suitable for both complementary variation of VF with absolute temperature (CTAT) and differential proportional to absolute temperature (PTAT) sensors, is demonstrated over 60–700 K, currently the widest range reported. The structure’s layout places the two identical diodes in close, symmetrical proximity. A stable and high-barrier Schottky contact based on Ni, annealed at 750 °C, is used. XRD analysis evinced the even distribution of Ni2Si over the entire Schottky contact area. Forward measurements in the 60–700 K range indicate nearly identical characteristics for the dual-diodes, with only minor inhomogeneity. Our parallel diode (p-diode) model is used to parameterize experimental curves and evaluate sensing performances over this far-reaching domain. High sensitivity, upwards of 2.32 mV/K, is obtained, with satisfactory linearity (R2 reaching 99.80%) for the CTAT sensor, even down to 60 K. The PTAT differential version boasts increased linearity, up to 99.95%. The lower sensitivity is, in this case, compensated by using a high-performing, low-cost readout circuit, leading to a peak 14.91 mV/K, without influencing linearity.

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Redox initiation in semicontinuous polymerization to search for specific mechanical properties of copolymers

e-Polymers ◽

10.1515/epoly-2020-0065 ◽

2020 ◽

Vol 20 (1) ◽

pp. 613-623

Author(s):

José Manuel Sandoval-Díaz ◽

Francisco Javier Rivera-Gálvez ◽

Marta Fernández-García ◽

Carlos Federico Jasso-Gastinel

Keyword(s):

Low Cost ◽

Mechanical Analysis ◽

Industrial Applications ◽

Size Exclusion ◽

Proton Nuclear Magnetic Resonance ◽

Polymerization Reaction ◽

Redox Initiation ◽

Initiation System ◽

Feeding Profile ◽

Chain Composition

AbstractIn this work, for a semicontinuous emulsion polymerization reaction, it is shown that using a redox initiation system at 40°C, substantial modifications in copolymer chain composition with conversion can be easily obtained. To test controllable trajectories for comonomer feeding, linear and parabolic profiles were chosen to get different types of chain composition variations for the 50/50 w/w styrene/n-butyl acrylate system. For the “forced composition copolymers,” the molecular weight averages and distribution were obtained by size exclusion chromatography. The composition along conversion was followed by proton nuclear magnetic resonance to determine the weight composition distribution (WCD) of the copolymer chains. Mechanodynamic (dynamic-mechanical analysis), tensile, and hardness tests exhibited consistent results depending on the WCD that outcomes from the respective feeding profile. The results confirm that this methodology is of great potential for industrial applications when looking for synergy in copolymer properties, and low-cost processes.

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On Performance of Two-Parameter Gompertz-Based X¯ Control Charts

Journal of Probability and Statistics ◽

10.1155/2020/8081507 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Johnson A. Adewara ◽

Kayode S. Adekeye ◽

Olubisi L. Aako

Keyword(s):

Control Chart ◽

Coverage Probability ◽

Control Charts ◽

Average Run Length ◽

Real Life ◽

Correction Method ◽

Gompertz Distribution ◽

Real Life Data ◽

Control Limits ◽

Two Parameter

In this paper, two methods of control chart were proposed to monitor the process based on the two-parameter Gompertz distribution. The proposed methods are the Gompertz Shewhart approach and Gompertz skewness correction method. A simulation study was conducted to compare the performance of the proposed chart with that of the skewness correction approach for various sample sizes. Furthermore, real-life data on thickness of paint on refrigerators which are nonnormal data that have attributes of a Gompertz distribution were used to illustrate the proposed control chart. The coverage probability (CP), control limit interval (CLI), and average run length (ARL) were used to measure the performance of the two methods. It was found that the Gompertz exact method where the control limits are calculated through the percentiles of the underline distribution has the highest coverage probability, while the Gompertz Shewhart approach and Gompertz skewness correction method have the least CLI and ARL. Hence, the two-parameter Gompertz-based methods would detect out-of-control faster for Gompertz-based X¯ charts.

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Computational Molecular Modeling of Transport Processes in Nanoporous Membranes

Processes ◽

10.3390/pr6080124 ◽

2018 ◽

Vol 6 (8) ◽

pp. 124 ◽

Cited By ~ 10

Author(s):

Kevin Hinkle ◽

Xiaoyu Wang ◽

Xuehong Gu ◽

Cynthia Jameson ◽

Sohail Murad

Keyword(s):

Molecular Modeling ◽

Temporal Resolution ◽

High Performance ◽

Low Cost ◽

Membrane Surface ◽

Experimental Studies ◽

Nanoporous Materials ◽

Transport Processes ◽

Zeolite Membrane ◽

Nanoporous Membranes

In this report we have discussed the important role of molecular modeling, especially the use of the molecular dynamics method, in investigating transport processes in nanoporous materials such as membranes. With the availability of high performance computers, molecular modeling can now be used to study rather complex systems at a fraction of the cost or time requirements of experimental studies. Molecular modeling techniques have the advantage of being able to access spatial and temporal resolution which are difficult to reach in experimental studies. For example, sub-Angstrom level spatial resolution is very accessible as is sub-femtosecond temporal resolution. Due to these advantages, simulation can play two important roles: Firstly because of the increased spatial and temporal resolution, it can help understand phenomena not well understood. As an example, we discuss the study of reverse osmosis processes. Before simulations were used it was thought the separation of water from salt was purely a coulombic phenomenon. However, by applying molecular simulation techniques, it was clearly demonstrated that the solvation of ions made the separation in effect a steric separation and it was the flux which was strongly affected by the coulombic interactions between water and the membrane surface. Additionally, because of their relatively low cost and quick turnaround (by using multiple processor systems now increasingly available) simulations can be a useful screening tool to identify membranes for a potential application. To this end, we have described our studies in determining the most suitable zeolite membrane for redox flow battery applications. As computing facilities become more widely available and new computational methods are developed, we believe molecular modeling will become a key tool in the study of transport processes in nanoporous materials.

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