Academic literature on the topic 'Paper Deterioration Testing'
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Journal articles on the topic "Paper Deterioration Testing"
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Mészáros, István, and János Ginsztler. "Magnetic Testing of Power Plant Steel Deterioration." Materials Science Forum 792 (August 2014): 183–88. http://dx.doi.org/10.4028/www.scientific.net/msf.792.183.
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Nowadays, there is increasing importance of the remaining life time estimation of engineering structures. In this work the thermal shock fatigue process induced deterioration of the three different power plant steels was investigated. The tested steels are widely used as steam pipeline base material of power plants. The applied thermal shock fatigue test can model the material degradation due to long term service in high temperature environment. A special AC magnetometer was designed and used for the magnetic measurements at the Department of Materials Science and Engineering of BUTE. In this paper a new high sensitivity magnetic measurement is presented for controlling the thermal shock fatigue deterioration. This measurement technique was developed for non-destructive testing of pipelines and pressure vessels of steam power plants.
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Woytowich, David L., Martin W. King, Myron G. Britton, and Jan A. Oleszkiewicz. "Accelerated testing of a filled polyester E-glass composite in acidic environments." Canadian Journal of Civil Engineering 18, no. 5 (October 1, 1991): 799–809. http://dx.doi.org/10.1139/l91-097.
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This paper describes the results of an accelerated laboratory investigation to measure the rate of deterioration of a newly developed filled plastic composite exposed to acidic (sewage) environments. The specific objective was to compare the relative rates of deterioration of an experimental filled filament wound (FFW) polyester composite immersed in sulfuric (pH 2.23) and acetic (pH 2.22) acid environments at 45 °C. Deterioration was measured in terms of changes in wet specimen weight, loss in dried (soluble) material weight and mechanical properties, the extent of chemical dissolution, and the depth of penetration. Based on regression analyses of these parameters, it was found that the rate of deterioration was a function of the square root of immersion time. Deterioration of the FFW composite in acetic acid was 1.6–3.9 times greater than in the sulfuric acid environment. The loss in wet flexural properties and the dissolution behavior of aluminum trihydrate were not influenced by the type of acid environment. Based on the findings of this study, sulfuric acid is recommended as a standard laboratory test medium for fiberglass reinforced plastic composites used in construction of sewage facilities and pipelines where deterioration due to sulfur oxidizing bacteria is anticipated. Key words: accelerated, polyester, fillers, filament-wound, environment, acidic, durability, composite, septic tanks.
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Feng, Ju, Tianhua Meng, Yuhe Lu, Jianguang Ren, Guozhong Zhao, Hongmei Liu, Jin Yang, and Rong Huang. "Nondestructive Testing of Hollowing Deterioration of the Yungang Grottoes Based on THz-TDS." Electronics 9, no. 4 (April 9, 2020): 625. http://dx.doi.org/10.3390/electronics9040625.
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Terahertz (THz) spectroscopy is an important method in noninvasive detection and diagnosis for historic relics. A new nondestructive testing (NDT) method based on terahertz time-domain spectroscopy (THz-TDS) technology was developed to measure the hollowing deterioration of the Yungang Grottoes in this paper. Hollowing deterioration samples were strictly prepared, and a series of experiments were conducted to ensure the representativeness of the experimental results. A hollowing thickness model was established by the relationship between the thickness of the hollowing deterioration sample and the time difference of the front flaked stone surface and the stone wall surface of the hollowing deterioration samples. The results show that the R-squared value of the model equation reached 0.99795, which implies that this model is reliable. Therefore, the actual hollowing thickness of the Yungang Grottoes can be obtained by substituting the time difference in the proposed thickness hollowing model, where the time difference is obtained from measured THz spectra. The detection method of stone relic hollowing deterioration is easy to apply, which can not only realize qualitative NDT but also quantitative hollowing deterioration thickness determination. This method has crucial practical significance for the repair and strengthening of stone relics similar to the Yungang Grottoes.
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Zielińska, Monika, and Magdalena Rucka. "Non-destructive Testing of Wooden Elements." IOP Conference Series: Materials Science and Engineering 1203, no. 3 (November 1, 2021): 032058. http://dx.doi.org/10.1088/1757-899x/1203/3/032058.
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Abstract Examining the condition of wooden elements is crucial from the perspective of proper structure performance. If the deterioration in the internal wood condition, which displays no symptoms visible from the outside, is detected, the further spread of the deterioration can be prevented. Test results often point to the necessity of conducting repairs and, renovations, replacing the structure of wooden beams, or even substituting a significant part of the structure. To achieve acceptable results, test methods should take into account the anisotropic nature of wood, which includes the shape of annual rings, as well as the location of the core in crosssection. To adopt methods based on physical effects, profound knowledge of wood physics is needed, particularly of interdependence. Apart from simple tests such as a visual inspection or tapping that are used to determine near-surface defects, non-destructive testing (NDT) plays an important role in the process. This paper presents the methods of non-destructive testing of wooden elements. These methods include tests conducted with ground penetrating radar (GPR), thermal techniques, microwaves, acoustic emission, ultrasonic tomography, and X-ray tomography. The paper summarises the use of non-destructive methods, indicating their advantages, disadvantages as well as some limitations.
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Reiterman, Pavel, and Ondřej Holčapek. "Mechanical and Durability Properties of Selected Types of Sandstones." Applied Mechanics and Materials 827 (February 2016): 324–27. http://dx.doi.org/10.4028/www.scientific.net/amm.827.324.
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Present paper is focused on the experimental assessment of three sandstones from different quarries. Mechanical testing was carried out besides water absorption test and determination of frost resistance what is the crucial material parameter for all types of porous rocks. Gradual deterioration due to action of frost was monitored using non-destructive testing – ultrasonic pulse method. Obtained results well describe failure mechanism of studied sandstones of different basic physical properties. It was conducted that main part of deterioration was performed at the beginning of the freeze-thaw cycling.
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Mészáros, István. "Testing of Power Plant Steel Deterioration by Adaptive Nonlinear Harmonics Method (ANLH)." Materials Science Forum 812 (February 2015): 351–56. http://dx.doi.org/10.4028/www.scientific.net/msf.812.351.
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Nowadays, there is increasing importance of the remaining life time estimation of engineering structures. In this work the thermal fatigue process induced deterioration of the three different power plant steels was investigated. The tested steels are widely used as steam pipeline base material of power plants. The applied thermal fatigue test can model the material degradation due to long term service in high temperature environment. In this paper a new high sensitivity magnetic measuring technique is presented called Adaptive Nonlinear Harmonic (ANLH) method. The sensitivity of this measurement is optimized for controlling the thermal fatigue deterioration. The presented novel measurement was developed for non-destructive testing of pipelines and pressure vessels of power plants.
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Niu, Xiang Jie, and Bin Lan. "The Agricultural Products Deterioration Recognition Based on Computer Vision." Applied Mechanics and Materials 602-605 (August 2014): 2027–30. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2027.
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The computer vision technology is an important branch of computer science and artificial intelligence which is regarded as a non-destructive testing technique in the field of agriculture with a broad application prospects. This paper introduces the application of the computer vision technology in the agricultural products deterioration recognition, builds foundations for the accurate measurement of the agricultural products quality with computer visions, and establish the relationship between the feature information and quality of the agricultural products. Meanwhile, this paper combined the computer vision technology with infrared, microwave, NMR techniques to extract and test the visual information of the internal quality of the agricultural products.
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Mechefske, C. K., and Y. Yang. "Failure diagnosis of a type of hydraulic knee joint controller." Prosthetics and Orthotics International 25, no. 2 (August 2001): 148–53. http://dx.doi.org/10.1080/03093640108726589.
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The development of the hydraulic artificial knee joint controller has significantly improved the quality of life for many amputees. Even though the controller unit is very reliable, gradual deterioration inevitably takes place because the unit consists of many moving parts and is subjected to repetitive loads. This paper describes a simple method to test the reliability of hydraulic artificial knee joint controllers. A life cycle testing machine for artificial knee controllers was designed as part of this programme. This study included life cycle testing of 5 knee controllers. Performance measurements representing the different degrees of deterioration were recorded and correlated against the actual deterioration found during refurbishment of the units. The results can be used (with care), together with simple tests, to judge performance of a given unit.
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ABDEL-KAREEM, OMAR. "Evaluating the Combined Efficacy of Polymers with Fungicides for Protection of Museum Textiles against Fungal Deterioration in Egypt." Polish Journal of Microbiology 59, no. 4 (2010): 271–80. http://dx.doi.org/10.33073/pjm-2010-041.
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Fungal deterioration is one of the highest risk factors for damage of historical textile objects in Egypt. This paper represents both a study case about the fungal microflora deteriorating historical textiles in the Egyptian Museum and the Coptic museum in Cairo, and evaluation of the efficacy of several combinations of polymers with fungicides for the reinforcement of textiles and their prevention against fungal deterioration. Both cotton swab technique and biodeteriorated textile part technique were used for isolation of fungi from historical textile objects. The plate method with the manual key was used for identification of fungi. The results show that the most dominant fungi isolated from the tested textile samples belong to Alternaria, Aspergillus, Chaetomium, Penicillium and Trichoderma species. Microbiological testing was used for evaluating the usefulness of the suggested conservation materials (polymers combined with fungicides) in prevention of the fungal deterioration of ancient Egyptian textiles. Textile samples were treated with 4 selected polymers combined with two selected fungicides. Untreated and treated textile samples were deteriorated by 3 selected active fungal strains isolated from ancient Egyptian textiles. This study reports that most of the tested polymers combined with the tested fungicides prevented the fungal deterioration of textiles. Treatment of ancient textiles by suggested polymers combined with the suggested fungicides not only reinforces these textiles, but also prevents fungal deterioration and increases the durability of these textiles. The tested polymers without fungicides reduce the fungal deterioration of textiles but do not prevent it completely.
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He, Ye, Kui Wang, Yuehui Ji, Guoyin Wu, and Mingjie Zhao. "Evaluation of Cumulative Damage of Sandstone under Cyclic Wetting and Drying through Acoustic Wave Parameters and Resistivity Testing." Journal of New Materials for Electrochemical Systems 23, no. 4 (December 31, 2020): 256–61. http://dx.doi.org/10.14447/jnmes.v23i4.a06.
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This paper carries out cyclic wetting and drying experiments on the sandstones from the bank slope of an inland port, and explores the deterioration features and acoustic wave parameters and resistivity (AWPR) of the sandstone. The variations in P-wave velocity, attenuation coefficient, nonlinear coefficient, resistivity, and other indices with the cycle number were discussed in details. Then, the correlations between P-wave velocity, resistivity, and physical-mechanical indices were analyzed based on the experimental results. Through the analysis on instantaneous damage analysis, a cumulative damage model was proposed, in the light of the AWPR. The results show that: the evolution of sandstone resistivity can accurately reflect the deterioration features of the sandstone under cyclic wetting and drying, providing a desirable tool to characterize rock strength deterioration and internal damage changes. Taking cycle number into account, the proposed theoretical model for cumulative damage can derive the damage and deterioration of sandstone excellently. By this model, the AWPR at any moment can be acquired in real time on site, which is convenient for engineering application.
Books on the topic "Paper Deterioration Testing"
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Samuelsson, Marie Louise. Naturligt åldrat papper: Svenska papper 1908-1988 = Natural ageing of paper : Swedish papers, 1908-1988. Stockholm: Riksarkivet, 1990.
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Cardwell, Robert David. The thermal stability of papermaking pulps. 1986.
Find full textConference papers on the topic "Paper Deterioration Testing"
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Koťátková, Jaroslava, Jan Patera, and Zbyněk Hlaváč. "Non-linear ultrasonic defectoscopy of concrete structures for nuclear industry." In The 13th international scientific conference “Modern Building Materials, Structures and Techniques”. Vilnius Gediminas Technical University, 2019. http://dx.doi.org/10.3846/mbmst.2019.013.
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Concrete structures exposed to neutron radiation may exhibit cracking and deterioration, therefore it is needed to find appropriate non-destructive testing methods for assessing their structural integrity. Non-linear wave modulation spectroscopy (NWMS) was developed for non-destructive detection of cracks inside concrete. The goal of this paper is to compare the results of conventional non-destructive and destructive testing methods to the proposed non-linear NWMS method applied to ordinary concrete samples. The concrete damage by neutron radiation was simulated by thermal loading of the samples. Ultrasonic impulse method, resonance method, non-linear wave modulation method, compressive strength and flexural strength testing methods were applied.
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Yu, Shujian, Xiaoyang Wang, and José C. Príncipe. "Request-and-Reverify: Hierarchical Hypothesis Testing for Concept Drift Detection with Expensive Labels." In Twenty-Seventh International Joint Conference on Artificial Intelligence {IJCAI-18}. California: International Joint Conferences on Artificial Intelligence Organization, 2018. http://dx.doi.org/10.24963/ijcai.2018/421.
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One important assumption underlying common classification models is the stationarity of the data. However, in real-world streaming applications, the data concept indicated by the joint distribution of feature and label is not stationary but drifting over time. Concept drift detection aims to detect such drifts and adapt the model so as to mitigate any deterioration in the model's predictive performance. Unfortunately, most existing concept drift detection methods rely on a strong and over-optimistic condition that the true labels are available immediately for all already classified instances. In this paper, a novel Hierarchical Hypothesis Testing framework with Request-and-Reverify strategy is developed to detect concept drifts by requesting labels only when necessary. Two methods, namely Hierarchical Hypothesis Testing with Classification Uncertainty (HHT-CU) and Hierarchical Hypothesis Testing with Attribute-wise "Goodness-of-fit" (HHT-AG), are proposed respectively under the novel framework. In experiments with benchmark datasets, our methods demonstrate overwhelming advantages over state-of-the-art unsupervised drift detectors. More importantly, our methods even outperform DDM (the widely used supervised drift detector) when we use significantly fewer labels.
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Gupta, Amit, and J. T. Kshirsagar. "Numerical Experiments on Solid Handling Pump." In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98004.
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Solid handling pumps are used in managing sewage and other solid materials that could flow along with the water or any other fluid. The design of solid handling pump components is also deviating significantly from clear water pump components. The flow passages need to be maintained to allow solid particles of specified sizes smoothly without any obstruction. This aspect of different design from conventional design causes performance deterioration of the pump. The laboratory testing of the solid handling pumps is normally carried out with clear water and a judgment is used based on experience about the deterioration in performance caused by solid particles (size and number of particles). The actual performance measurement with varying particle sizes and its cluster density is very rarely available. A case of solid handling pump is taken up for detail investigation using numerical approach. The preliminary analysis has been carried out with solid handling impeller with clear water as medium of flow. The solid particles are then injected with different sizes and number of solid. Both Eulerian and Langrangian multiphase flow (MPF) approach have been used to study the hydraulic performance deterioration and particle trajectory in the working pump. The paper describes the approaches used and discusses the results considering generally accepted behavior of solid handing pumps.
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Limaye, Hemant S. "Evaluation of Concrete Structures Using Nondestructive Techniques." In 2012 20th International Conference on Nuclear Engineering and the ASME 2012 Power Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icone20-power2012-54088.
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To renew the expiring licenses of the nuclear power plants, the operators will need to evaluate major structural components for the age related deterioration. Assessment of the interior of the concrete structures can be made using the available nondestructive testing (NDT) methods. This paper presents a quick overview of the methods and describes how some of these methods were used for the two projects-one for the new construction and one for the existing project going through the modification/renovation.
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Apprill, Bob, Logan Coen, Brian Gessler, Jonathan Mattson, and Christopher Depcik. "Fixed Bed Solid Fuel Combustor for the Purpose of Testing Solid Biomass Emissions Properties." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36543.
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Fossil fuels place a large strain on the environment due to the pollution produced through their extraction and usage. One method to reduce societal fossil fuel usage is through co-combustion of coal with woody biomass. However, overproduction of this biomass may lead to significant environmental deterioration. A potential sustainable substitute for the woody biomass is in the form of dried algae. Because the emission characteristics of algae combustion are unknown, a simple dry mass combustor was constructed, including necessary instrumentation, as part of an undergraduate design class with the goal of a more thorough characterization of algae’s combustion properties. The combustor is a simple and affordable design, in keeping with the classes’ principles of sustainability through a focus on energy, environment, and economy. The combustor consists of a flow controller that sends air into a metallic plenum, where modulations in flow are reduced before it is sent to a steel pipe for combustion. This paper describes the concepts involved in the design of this combustor, and preliminary assessment efforts employing the system when testing biomass pellets. Testing showed combustion efficiency greater than 98%, and the data clearly illustrates three separate phases to the reaction process, with rapid changes in emissions and temperature punctuating the ends of these phases.
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Khanbikova, Regina, Venera Bazarevskaya, Oleg Sotnikov, and Albert Bachkov. "Oil Saturation Index in Hydrophobic Carbonate Reservoir: Evaluation Aspects." In SPE Symposium: Petrophysics XXI. Core, Well Logging, and Well Testing. SPE, 2021. http://dx.doi.org/10.2118/208416-ms.
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Abstract Hydrocarbon reserves in carbonate reservoirs account for 38% - 60% of total world reserves, according to different estimates. In Tatarstan, carbonate reservoirs are found, mostly, in the eastern slope of the Melekess Depression and the South-Tatarian Arch. The carbonate reservoirs are confined to the Middle and Lower Carboniferous sediments, the Upper Devonian (including the domanik sediments), and the Upper Permian (the Kazanian heavy oil accumulations). Considering an extensive geographic and stratigraphic range and differing tectonic and sedimentation environments, the carbonate rocks are characterized by a variety of reservoir properties. In contrast to terrigenous rocks, the carbonate void space is complicated by secondary processes that took place much later than the sedimentogenesis-lithogenesis stage. Numerous fissures, caves, sutures, and stylolites form the void space of the reservoir rock matrix containing commercial hydrocarbon reserves. In addition to fracturing and vugginess contributing to increase of void space of carbonate rocks, the secondary processes include sulphatisation and secondary dolomitization (in limestones), adding to deterioration of reservoir properties. The secondary processes impede understanding and evaluation of reservoir properties and saturation potential, in particular, determination of the oil and gas saturation factors (Dyakonova T.F. et al, 2019, Akhmetov R.T. et al, 2017)/ In the western slope of the South-Tatarian Arch, carbonate reservoirs are confined to the Middle and Lower Carboniferous sediments. Numerous RCAL and SCAL investigations provided valuable insight into these targets. In this paper, we used data from the laboratory experiments and studies of core and oil samples from the six neighbor fields on the western slope of the South-Tatarian Arch. Because of common sedimentological and tectonic sedimentation environments and lithological similarity of rocks within the stratigraphic referencing, the six fields under analysis were considered as analogous, and the results of the laboratory studies of the samples were reviewed collectively.
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Madsen, Stian, Jørn Watvedt, and Lars E. Bakken. "Gas Turbine Fouling Offshore: Air Intake Filtration Optimization." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75613.
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Optimized operation of gas turbines is discussed for a fleet of eleven LM2500PE engines at a Statoil North Sea offshore field in Norway. Three engines are generator drivers while eight engines are compressor drivers. Several of the compressor drive engines run at peak load (T5.4 control), hence production rate is limited by the available power from these engines. The majority of the engines discussed run continuously without redundancy, hence gas turbine uptime is critical for the field’s production and economy. The performance and operational experience with upgraded inlet air filter systems, as well as successful operation at longer maintenance intervals and higher average engine performance are described. For North Sea operation, a key property of the filter system is the ability to handle high humidity and high salt-content, typical of the harsh environment in these waters. The upgraded filter system analyzed in this paper is a 2-stage system (vane separator stage upstream of the high-efficiency filter stage), which is a simplified design versus the old traditional 3-stage systems (louvre upstream and vane separator downstream of the filter stage). These 2-stage systems rely on an efficient upstream vane separator to remove the vast majority of water from the airflow before it reaches the high-efficiency filters. The high-efficiency filters are specially designed to withstand moisture. The effectiveness and contribution of each component in the filtration system are described. Extensive testing of both new and used filter elements, of different filter grade and operated at different intervals, has been performed in a filter test rig facility onshore. Extensive testing of used filters has also been performed at the filter OEM, where filter efficiency is measured as well as destructive testing and analysis of the filter layers. The effect of an optimized air intake filter system for the subject engines, is longer operating intervals, higher power availability and lower engine deterioration. The operating intervals are now extended to six months (4,000 hours), from initially two months (1,500 hours, early 1990s) then four months (3,000 hours, mid 2000s). The HPC efficiency deterioration is reduced by some 3% related to intake filter system, of a total of over 6% in efficiency deterioration over each 6-month operating period.
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Aronian, Abe, Kim Wachs, Michelle Jamieson, Karen Carriere, and Edward W. Gaughan. "Testing and Validation of Long Trains Under High Flow and Gradient Conditions." In 2012 Joint Rail Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/jrc2012-74036.
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The need to extend train lengths has been a primary business target of the railway industry, due to its obvious benefits. However, winter train operating conditions, excessive in-train slack action, deterioration of air brake signal propagation and the added stress on infrastructure and equipment has naturally kept the average train lengths at bay. The introduction of advanced equipment, new concepts and strategies have now enabled Canadian Pacific to change this mindset. Long Train make up is now very possible, taking into account the Distributed Power configuration. Making a very long train resemble a series of short trains coupled together, each with its own locomotives, synchronously connected to the Lead unit’s commands, makes such trains very safe and efficient. Extensive Field Testing and Train Simulation work done over the last two years at CP has shown that with the use of Multiple Remote Locomotive set-up, it is in fact very possible to safely contemplate extending the limits of today’s maximum allowed 60 CFM of total train air flow, into uncharted territory, possibly approaching a total of 90 CFM. CP has pursued to implement on a permanent basis, operating instructions that would permit Multiple Distributed Power trains to depart from a train brake test location with combined air flow of up to 90 CFM, provided the flow at each DP locomotive consist is not greater than 60 CFM and train length sections between locomotives are not exceeded. This paper investigates the operation of Distributed Power trains at higher levels of air flow and, through detail field testing and evaluation techniques, substantiates the validity of extending the safety limits of train leakage and gradient for such trains.
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Artus, Mathias, Martin Schickert Schickert, Jason Lai, and Christian Koch. "Integration of Wave-Based Non-Destructive Survey Results into BIM Models." In The 29th EG-ICE International Workshop on Intelligent Computing in Engineering. EG-ICE, 2022. http://dx.doi.org/10.7146/aul.455.c221.
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Aging bridges and rising load indices induce increases in bridge deterioration. Several nationalities conduct non-destructive testing (NDT) methods to analyze current bridge conditions. Traditionalpractice relies on exchanging plans and reports. However, sufficient planning and interpretation of NDT surveys require comprehensive building information. Building Information Modeling (BIM) has become an established concept for design, planning, and construction of buildings and structures. Combining the concept of BIM and NDT promises benefits in case of planning and performing surveys and interpret resultant data. This paper describes a framework that incorporates building information, inspection data,and data ofwave-based surveys, for instanceultrasonic and Ground Penetrating Radar (GPR),to allow in-depth building assessment.
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Van Den Andel, J. "Limitations of Thermocouples Used in Hot Zones in Gas Turbines." In ASME 1986 International Gas Turbine Conference and Exhibit. American Society of Mechanical Engineers, 1986. http://dx.doi.org/10.1115/86-gt-205.
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Thermocouples are extensively used for controlling as well as safeguarding gas turbines. Some thermocouples have found their way into environments where their life expectancy could not be fulfilled. The literature provides very little information on thermocouple used beyond 3000 hours and yet in gas turbines, 30 000 h expectancy is not uncommon. In the hottest zones, deterioration takes place in spite of special precautions in shielding. A test was developed to find troubles which could not be revealed by calibration or other means of testing. Thermocouples thus identified had lives of less than half the design value and restrictions have been placed on the time span a thermocouple is considered useful. The paper follows a practical approach to a practical problem.