scholarly journals Cost-effective ultrasonic inspection of large diameter pipelines

2020 ◽  
Vol 4 (2) ◽  
pp. 108-116
Author(s):  
Ries Augustijn ◽  
◽  
João Gonçalves ◽  
Joost Haaksman ◽  
◽  
...  
Keyword(s):  
High Resolution ◽  
Large Diameter ◽  
Ultrasonic Inspection ◽  
Real Life ◽  
Cost Effective ◽  
Operating Conditions ◽  
Limiting Factor ◽  
Technological Capabilities ◽  
High Salinity Water ◽  
The Right

To be successful in the ILI business, organization require the right mix of technological capabilities, operational agility and quality standards. The business is fairly competitive, and often technological capabilities are pivotal in the customer proposition of the company. However, the best technologies are not solely required for successful ILI companies. Robustness of the system, operability by the ILI inspector, fitness of the product with commercial route to the market all contribute to a rapid return on investment. Providing a robust, versatile, high-resolution and cost-effective method to inspect large diameter pipelines was recognized as a challenge and opportunity. For that, a Large Diameter Ultrasonic Inspection tool capable of inspecting pipelines of 20 inch to 64 inch with high resolution was developed. The tool is always bi-directional and capable of mitigating 1.5D bends. Gathered data can be reviewed real-time during the inspection. The operating envelope of the tool is such that it can cope with various products in the pipeline, varying from (high salinity) water, crude oil and a multitude of refined products. Despite the fact that product properties (e.g. speed of sound, attenuation, temperature, etc) vary, the tool is designed such that this is not a limiting factor for the operating envelope. The application of advanced ultrasonic beam forming methodologies and signal generation and -processing ensure that the system is versatile and robust for these types of real-life operating conditions. This presentation will provide an overview of the utilization of these technologies, the validation program that has been used to demonstrate tool specifications and the experiences gained at successful projects.

Web Based Nondestructive Evaluation Using Acoustic Emission

2009 ◽  
Author(s):  
Samuel J. Ternowchek ◽  
Ronnie K. Miller ◽  
Phillip T. Cole
Keyword(s):  
Nondestructive Evaluation ◽  
Structural Integrity ◽  
Cost Effective ◽  
Operating Conditions ◽  
Web Based ◽  
Continuous Basis ◽  
The Right ◽  
Real Time Information ◽  
Time Information ◽  
Fixed Period

As operating equipment and structures age, the probability of failure increases. Increasing inspection cycles (over some fixed period of time) with conventional nondestructive evaluation (NDE) is one way to address this problem but it comes at a cost. In addition, an uncertainty exists that the right area(s) have been inspected during one of these inspection cycles. As a result, there is a need for a technique and method that provides the user with real time information about structural integrity or operating conditions. This technique and method must be cost effective and minimize the need for a person to be near the structure operating equipment in order to obtain data on a continuous basis.

Feasibility Analysis for Repair of Large Diameter Hydro Turbine Shaft Based on Weldability Test and Welding Cycle Simulation

2019 ◽  
Vol 1153 ◽  
pp. 36-45
Author(s):  
Dejan Momčilović ◽  
Zoran Odanović
Keyword(s):  
Failure Analysis ◽  
Good Practice ◽  
Large Diameter ◽  
Indirect Costs ◽  
Operating Conditions ◽  
Feasibility Analysis ◽  
Hydro Turbine ◽  
Cycle Simulation ◽  
Alloy Heat ◽  
The Right

Turbine and generator rotors and shafts undergo high stresses during regular working life and, from a safety and operational aspect, are the most significant components of a power generation system. Depending on the appropriate operating conditions, like temperature and/or corrosion the, shafts can be fabricated out of low/high alloy heat resistance material or of low alloyed, highly toughened material for different application. Despite known good practice and developed operation procedures, the failures of shafts sometimes occur. The right and well-defined failure analysis is the basis for feasibility analysis of repair method in the power generating industry. The analysis of direct and indirect costs of repair after the failure analysis as well as the analysis of the repair and post-repair conditions of the repaired element is the vital for decision on the key question. Is it possible to repair this element and what is the optimal repair strategy? This paper compares and analyses two approaches, by weldability analysis and weld cycle simulation, in order to determine welding feasibility analysis of cracked hydro turbine shafts.

scholarly journals Evaluation of Co and Nox Emissions in Real-Life Operating Conditions of Herbaceous Biomass Briquettes Combustion

2020 ◽  
Vol 23 (2) ◽  
pp. 53-59
Author(s):  
Jan Malaťák ◽  
Jan Velebil ◽  
Jiří Bradna ◽  
Arkadiusz Gendek ◽  
Barbora Tamelová
Keyword(s):  
Carbon Monoxide ◽  
Flue Gas ◽  
Combustion Process ◽  
Real Life ◽  
Phalaris Arundinacea ◽  
Operating Conditions ◽  
Limiting Factor ◽  
Reed Canary Grass ◽  
Canary Grass ◽  
Combustion Tests

AbstractThe issue of carbon monoxide and nitrogen oxides emissions into the atmosphere is very current. This article thus focuses on the assessment of elemental composition of selected herbal biomass species and emission concentrations during combustion in a commonly available grate combustion device for briquetted fuel. In tests, emission concentrations were evaluated in contrast to the oxygen concentration in flue gas and flue gas temperatures. Samples of camelina (Camelina sativa), giant miscanthus (Miscanthus gigantheus), reed canary grass (Phalaris arundinacea L.) and sorghum (Sorghum bicolor) were used. Elementary and stoichiometric combustion analyses were conducted for these samples (LECO AC-600 semi-automatic calorimeter, CHN628 + S elemental analyser and LECO TGA-701 analyser). Analyses of C, H, N and S concentrations and calorific values showed that samples of briquetted herb biomass had insignificant differences and could be used for energy purposes without limitation. The limiting factor was the high amount of ash, which amounted to 6.59% of dry weight in reed canary grass briquette sample. Furthermore, a high percentage (1.91% wt.) of nitrogen was observed in reed canary grass briquettes. Such a high amount of nitrogen during combustion tests resulted in an increase in NOx emission levels in flue gas of the Phalaris arundinacea L. sample, in which it reached the maximum concentration of 375.20 mg·m−3. The combustion tests showed that even under steady-state conditions, high concentrations of carbon monoxide could not be avoided for tested briquetted biofuels without active regulation of the combustion process.

Slow-scan CCD cameras and low-dose High-Resolution Electron Microscopy: Direct and quantitative

1994 ◽  
Vol 52 ◽  
pp. 412-413
Author(s):  
M. Pan
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Structural Damage ◽  
Low Dose ◽  
Dynamic Range ◽  
High Resolution Electron Microscopy ◽  
Operating Conditions ◽  
Digital Data ◽  
Ccd Cameras ◽  
Resolution Electron

It has been known for many years that materials such as zeolites, polymers, and biological specimens have crystalline structures that are vulnerable to electron beam irradiation. This radiation damage severely restrains the use of high resolution electron microscopy (HREM). As a result, structural characterization of these materials using HREM techniques becomes difficult and challenging. The emergence of slow-scan CCD cameras in recent years has made it possible to record high resolution (∽2Å) structural images with low beam intensity before any apparent structural damage occurs. Among the many ideal properties of slow-scan CCD cameras, the low readout noise and digital recording allow for low-dose HREM to be carried out in an efficient and quantitative way. For example, the image quality (or resolution) can be readily evaluated on-line at the microscope and this information can then be used to optimize the operating conditions, thus ensuring that high quality images are recorded. Since slow-scan CCD cameras output (undistorted) digital data within the large dynamic range (103-104), they are ideal for quantitative electron diffraction and microscopy.

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

Infrared Emission Spectroscopy as a Reliability Tool

1999 ◽  
Author(s):  
Q. Kim ◽  
S. Kayali
Keyword(s):  
Spatial Resolution ◽  
Emission Spectroscopy ◽  
Hot Spot ◽  
Cost Effective ◽  
Infrared Emission ◽  
Test System ◽  
Operating Conditions ◽  
Yield Enhancement ◽  
Infrared Emission Spectroscopy ◽  
Channel Temperature

Abstract In this paper, we report on a non-destructive technique, based on IR emission spectroscopy, for measuring the temperature of a hot spot in the gate channel of a GaAs metal/semiconductor field effect transistor (MESFET). A submicron-size He-Ne laser provides the local excitation of the gate channel and the emitted photons are collected by a spectrophotometer. Given the state of our experimental test system, we estimate a spectral resolution of approximately 0.1 Angstroms and a spatial resolution of approximately 0.9 μm, which is up to 100 times finer spatial resolution than can be obtained using the best available passive IR systems. The temperature resolution (<0.02 K/μm in our case) is dependent upon the spectrometer used and can be further improved. This novel technique can be used to estimate device lifetimes for critical applications and measure the channel temperature of devices under actual operating conditions. Another potential use is cost-effective prescreening for determining the 'hot spot' channel temperature of devices under normal operating conditions, which can further improve device design, yield enhancement, and reliable operation. Results are shown for both a powered and unpowered MESFET, demonstrating the strength of our infrared emission spectroscopy technique as a reliability tool.

Biochemical and Histopathological Evaluation of the Radioprotective Effects of Melatonin Against Gamma Ray-Induced Skin Damage

2019 ◽  
Vol 12 (1) ◽  
pp. 72-81 ◽  
Author(s):  
Dheyauldeen Shabeeb ◽  
Masoud Najafi ◽  
Ahmed Eleojo Musa ◽  
Mansoor Keshavarz ◽  
Alireza Shirazi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Histopathological Examination ◽  
Radical Scavenging ◽  
Limiting Factor ◽  
Skin Damage ◽  
Exposed Skin ◽  
Male Wistar Rats ◽  
Time Periods ◽  
Skin Damages ◽  
The Right

Background:Radiotherapy is one of the treatment methods for cancers using ionizing radiations. About 70% of cancer patients undergo radiotherapy. Radiation effect on the skin is one of the main complications of radiotherapy and dose limiting factor. To ameliorate this complication, we used melatonin as a radioprotective agent due to its antioxidant and anti-inflammatory effects, free radical scavenging, improving overall survival after irradiation as well as minimizing the degree of DNA damage and frequency of chromosomal abrasions.Methods:Sixty male Wistar rats were randomly assigned to 4 groups: control (C), melatonin (M), radiation (R) and melatonin + radiation (MR). A single dose of 30 Gy gamma radiation was exposed to the right hind legs of the rats while 40 mg/ml of melatonin was administered 30 minutes before irradiation and 2 mg/ml once daily in the afternoon for one month till the date of rat’s sacrifice. Five rats from each group were sacrificed 4, 12 and 20 weeks after irradiation. Afterwards, their exposed skin tissues were examined histologically and biochemically.Results:In biochemical analysis, we found that malondialdehyde (MDA) levels significantly increased in R group and decreased significantly in M and MR groups after 4, 12, and 20 weeks, whereas catalase (CAT) and superoxide dismutase (SOD) activities decreased in the R group and increased in M and MR groups during the same time periods compared with the C group (p<0.05). Histopathological examination found there were statistically significant differences between R group compared with the C and M groups for the three different time periods (p<0.005, p<0.004 and p<0.004) respectively, while R group differed significantly with MR group (p<0.013). No significant differences were observed between C and M compared with MR group (p>0.05) at 4 and 20 weeks except for inflammation and hair follicle atrophy, while there were significant effects at 12 weeks (p<0.05).Conclusion:Melatonin can be successfully used for the prevention and treatment of radiation-induced skin injury. We recommend the use of melatonin in optimal and safe doses. These doses should be administered over a long period of time for effective radioprotection and amelioration of skin damages as well as improving the therapeutic ratio of radiotherapy.

scholarly journals Neural alignment predicts learning outcomes in students taking an introduction to computer science course

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Meir Meshulam ◽  
Liat Hasenfratz ◽  
Hanna Hillman ◽  
Yun-Fei Liu ◽  
Mai Nguyen ◽  
...  
Keyword(s):  
Computer Science ◽  
Learning Outcomes ◽  
Brain Activity ◽  
Activity Patterns ◽  
Real Life ◽  
Final Exam ◽  
Neural Representations ◽  
Real Life Setting ◽  
The Right ◽  
Mri Study

AbstractDespite major advances in measuring human brain activity during and after educational experiences, it is unclear how learners internalize new content, especially in real-life and online settings. In this work, we introduce a neural approach to predicting and assessing learning outcomes in a real-life setting. Our approach hinges on the idea that successful learning involves forming the right set of neural representations, which are captured in canonical activity patterns shared across individuals. Specifically, we hypothesized that learning is mirrored in neural alignment: the degree to which an individual learner’s neural representations match those of experts, as well as those of other learners. We tested this hypothesis in a longitudinal functional MRI study that regularly scanned college students enrolled in an introduction to computer science course. We additionally scanned graduate student experts in computer science. We show that alignment among students successfully predicts overall performance in a final exam. Furthermore, within individual students, we find better learning outcomes for concepts that evoke better alignment with experts and with other students, revealing neural patterns associated with specific learned concepts in individuals.

scholarly journals Practical Cross-Layer Radio Frequency-Based Authentication Scheme for Internet of Things

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 4034
Author(s):  
Arie Haenel ◽  
Yoram Haddad ◽  
Maryline Laurent ◽  
Zonghua Zhang
Keyword(s):  
Internet Of Things ◽  
Radio Frequency ◽  
Real Life ◽  
Computation Time ◽  
Cost Effective ◽  
Battery Life ◽  
Cross Layer ◽  
Security Level ◽  
Cost Of Energy ◽  
Iot Devices

The Internet of Things world is in need of practical solutions for its security. Existing security mechanisms for IoT are mostly not implemented due to complexity, budget, and energy-saving issues. This is especially true for IoT devices that are battery powered, and they should be cost effective to be deployed extensively in the field. In this work, we propose a new cross-layer approach combining existing authentication protocols and existing Physical Layer Radio Frequency Fingerprinting technologies to provide hybrid authentication mechanisms that are practically proved efficient in the field. Even though several Radio Frequency Fingerprinting methods have been proposed so far, as a support for multi-factor authentication or even on their own, practical solutions are still a challenge. The accuracy results achieved with even the best systems using expensive equipment are still not sufficient on real-life systems. Our approach proposes a hybrid protocol that can save energy and computation time on the IoT devices side, proportionally to the accuracy of the Radio Frequency Fingerprinting used, which has a measurable benefit while keeping an acceptable security level. We implemented a full system operating in real time and achieved an accuracy of 99.8% for the additional cost of energy, leading to a decrease of only ~20% in battery life.

scholarly journals Removal of heavy metal ions from wastewater: a comprehensive and critical review

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Naef A. A. Qasem ◽  
Ramy H. Mohammed ◽  
Dahiru U. Lawal
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Large Volume ◽  
Heavy Metal Ions ◽  
Membrane Separation ◽  
Cost Effective ◽  
Operating Conditions ◽  
Future Research ◽  
Sludge Formation ◽  
Metals Removal

AbstractRemoval of heavy metal ions from wastewater is of prime importance for a clean environment and human health. Different reported methods were devoted to heavy metal ions removal from various wastewater sources. These methods could be classified into adsorption-, membrane-, chemical-, electric-, and photocatalytic-based treatments. This paper comprehensively and critically reviews and discusses these methods in terms of used agents/adsorbents, removal efficiency, operating conditions, and the pros and cons of each method. Besides, the key findings of the previous studies reported in the literature are summarized. Generally, it is noticed that most of the recent studies have focused on adsorption techniques. The major obstacles of the adsorption methods are the ability to remove different ion types concurrently, high retention time, and cycling stability of adsorbents. Even though the chemical and membrane methods are practical, the large-volume sludge formation and post-treatment requirements are vital issues that need to be solved for chemical techniques. Fouling and scaling inhibition could lead to further improvement in membrane separation. However, pre-treatment and periodic cleaning of membranes incur additional costs. Electrical-based methods were also reported to be efficient; however, industrial-scale separation is needed in addition to tackling the issue of large-volume sludge formation. Electric- and photocatalytic-based methods are still less mature. More attention should be drawn to using real wastewaters rather than synthetic ones when investigating heavy metals removal. Future research studies should focus on eco-friendly, cost-effective, and sustainable materials and methods.

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