An Analysis Model and its Practical Applications in PG&E Gas Transmission Pipeline Strength Test Projects

2018 ◽  
Author(s):  
Chunlei He ◽  
Edward Stracke
Keyword(s):  
Critical Role ◽  
Ideal Gas ◽  
Strength Test ◽  
Future Application ◽  
Test Duration ◽  
Test Medium ◽  
Analysis Model ◽  
Practical Applications ◽  
Pipeline Section ◽  
Strength Tests

This article presents a complete set of calculations (referred to as Model) PG&E developed to monitor, assess and approve strength tests on insitu (pipelines currently in service) gas transmission pipelines. How the Model is used in the field, 2017 test results, and process improvements that resulted from the implementation of the model are also discussed. In compliance with CPUC directives, the Code of Federal Regulations[1] and PG&E’s internal standards, PGE has performed strength tests on approximately 1,100 miles of insitu pipelines from 2011 through 2017. The model was specifically designed to assess the strength test of a closed section of gas pipeline for both leaks and ruptures. The model was originally designed for strength tests using water as the test medium and updated to accommodate nitrogen as a test medium. A future enhancement will be to incorporate a blend of Nitrogen and Helium as the test medium. The model plots the pressure-temperature and pressure-volume curves over the test duration (field test measurements) and compares them to the theoretically calculated curves. The curves are used to determine if the change in pressure is due to temperature influence or leakage. When water is the test medium, the model calculates the net corrected medium volume change from start to end of the static test period. When nitrogen is the test medium, the model calculates and analyzes net mass change of the medium by considering nitrogen under both the real gas state and the ideal gas state. By calculating restrained (buried) pipeline section and unrestrained (exposed) pipeline section separately, the model gains more accuracy. Accurate temperature measurements play a critical role in the model. The model makes it possible for engineers to monitor, analyze and direct strength tests with real-time test data. The model is also used to evaluate the pipeline fill condition on the day prior to the actual test, which resulted in fewer test restarts due to incomplete fill or temperature stabilization issues. An additional benefit is the tests were typically completed earlier in the day. The model is utilized on all PG&E insitu pipeline strength projects today. Authors also provide improvement suggestions of this model in future application.

Experimental and Numerical Analysis of the Transient Behavior of the Oil De-Congealing Process in an Aero Fuel-Cooled Oil Cooler Under Low-Temperature Conditions

2021 ◽  
Author(s):  
Foster Kwame Kholi ◽  
Jaehyun Park ◽  
Kyeongho Lee ◽  
Man Yeong Ha ◽  
Michael Klingsporn ◽  
...  
Keyword(s):  
Low Temperature ◽  
Boundary Conditions ◽  
Critical Role ◽  
Transient Behavior ◽  
Analysis Model ◽  
Practical Applications ◽  
Fuel Flow ◽  
Commercial Code ◽  
Study Results ◽  
Oil Cooler

Abstract The fuel-cooled oil cooler (FCOC) in the lubrication circuit plays a critical role in the aero gas-turbine engine's aerothermal management. However, the low temperature of the operating environment can congeal the oil and reduce the FCOC efficiency. The oil bypass valve (OBV) installed on the FCOC prevents pressure loss. Its failure may cause overheating, requiring preemptive performance prediction. Experimental and numerical analyses were used to evaluate the cooler's de-congealing performance under typical boundary conditions of pressure and temperature, OBV configurations, and re-routing of feed oil and fuel flow paths. The temporal variation of oil and fuel mass flow rates, temperature, and pressure of the feed oil and fuel provided an insight into the de-congealing process and duration. The experimental data were used to develop a one-dimensional (1D) flow and thermal network analysis model based on the effectiveness (e)-NTU method to predict the transient oil de-congealing performance of the FCOC. The customized commercial code predicted the de-congealing phenomena using empirical correlations with property correction schemes, showing good agreement with the experiment. The findings revealed various ways to enhance the de-congealing performance of the FCOC. The study results showed that the operating boundary conditions, OBV location and status, and flow arrangements affect de-congealing behavior and time. The present numerical model provides results quickly and can effectively predict experimentally costly and complicated cases. The attempted estimates of steady heat rejection and detailed methodology could guide future studies and practical applications.

Recent Advances in the Function of the 67 kDa Laminin Receptor and its Targeting for Personalized Therapy in Cancer

2017 ◽  
Vol 23 (32) ◽  
pp. 4745-4757 ◽  
Author(s):  
Ada Pesapane ◽  
Pia Ragno ◽  
Carmine Selleri ◽  
Nunzia Montuori
Keyword(s):  
Cell Adhesion ◽  
Cancer Progression ◽  
Ribosome Biogenesis ◽  
Critical Role ◽  
Protein Translation ◽  
Basement Membranes ◽  
Laminin Receptor ◽  
Cell Surface Receptor ◽  
Future Application ◽  
Neoplastic Cells

The 67 kDa high affinity laminin receptor (67LR) is a non-integrin cell surface receptor for laminin, the major component of basement membranes. Interactions between 67LR and laminin play a major role in mediating cell adhesion, migration, proliferation and survival. 67LR derives from homo- or hetero-dimerization of a 37 kDa cytosolic precursor (37LRP), most probably by fatty acid acylation. Interestingly, 37LRP, also called p40 or OFA/iLR (oncofetal antigen/immature laminin receptor), is a multifunctional protein with a dual activity in the cytoplasm and in the nucleus. In the cytoplasm, 37LRP it is associated with the 40S subunit of ribosome, playing a critical role in protein translation and ribosome biogenesis while in the nucleus it is tightly associated with nuclear structures, and bound to components of the cytoskeleton, such as tubulin and actin. 67LR is mainly localized in the cell membrane, concentrated in lipid rafts. Acting as a receptor for laminin is not the only function of 67LR; indeed, it also acts as a receptor for viruses, bacteria and prions. 67LR expression is increased in neoplastic cells and correlates with an enhanced invasive and metastatic potential. The primary function of 67LR in cancer is to promote tumor cell adhesion to basement membranes, the first step in the invasion-metastasis cascade. Thus, 67LR is overexpressed in neoplastic cells as compared to their normal counterparts and its overexpression is considered a molecular marker of metastatic aggressiveness in cancer of many tissues, including breast, lung, ovary, prostate, stomach, thyroid and also in leukemia and lymphoma. Thus, inhibiting 67LR binding to laminin could be a feasible approach to block cancer progression. Here, we review the current understanding of the structure and function of this molecule, highlighting its role in cancer invasion and metastasis and reviewing the various therapeutic options targeting this receptor that could have a promising future application.

Two-dimensional metal carbides and nitrides (MXenes): preparation, property, and applications in cancer therapy

Nanophotonics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 2125-2145 ◽  
Author(s):  
Lu Ming Dong ◽  
Cui Ye ◽  
Lin Lin Zheng ◽  
Zhong Feng Gao ◽  
Fan Xia
Keyword(s):  
Cancer Therapy ◽  
Scientific Community ◽  
Critical Role ◽  
High Specific Surface Area ◽  
Future Perspective ◽  
Two Dimensional ◽  
Metal Carbides ◽  
Practical Applications ◽  
Two Dimensional Materials ◽  
Size And Morphology

AbstractTransition metal carbides and nitrides (MXenes), which comprise a rapidly growing family of two-dimensional materials, have attracted extensive attention of the scientific community, owing to its unique characteristics of high specific surface area, remarkable biocompatibility, and versatile applications. Exploring different methods to tune the size and morphology of MXenes plays a critical role in their practical applications. In recent years, MXenes have been demonstrated as promising nanomaterials for cancer therapy with substantial performances, which not only are helpful to clarify the mechanism between properties and morphologies but also bridge the gap between MXene nanotechnology and forward-looking applications. In this review, recent progress on the preparation and properties of MXenes are summarized. Further applications in cancer therapy are also discussed. Finally, the current opportunities and future perspective of MXenes are described.

scholarly journals EARLY STRENGTH TESTING AFTER ACL RECONSTRUCTION IMPACTS ISOKINETIC STRENGTH PERFORMANCE AT TIME OF RETURN TO SPORT

2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0011
Author(s):  
Adam Weaver ◽  
Dylan Roman ◽  
Maua Mosha ◽  
Nicholas Giampetruzzi
Keyword(s):  
Test Performance ◽  
Knee Extension ◽  
Strength Test ◽  
Strength Testing ◽  
Isokinetic Strength ◽  
Rehabilitation Process ◽  
Strength Performance ◽  
Knee Extension Strength ◽  
Isometric Knee Extension ◽  
Strength Tests

Background: The standard of care in ACL reconstruction (ACLR) typically involves standardized strength testing at 6 months or later to assess a patient’s readiness to return to play (RTP) using isokinetic and isometric testing, and functional strength testing. Recent literature suggests that isokinetic knee extension strength should demonstrate 89% limb symmetry index (LSI) or greater prior to returning to sport. However, there is little known on the effects of strength testing early in the rehabilitation process and the relationship to strength test performance at time of RTP. Purpose: The purpose of this study was to examine how early post-operative strength test performance impacts isokinetic strength outcomes at RTP testing in adolescents. Methods: The retrospective cohort study included patients undergoing primary ACLR between 12 and 18 years of age, early post-operative strength measures, and isokinetic dynamometer strength at RTP from July 2017 and April 2019. Data was dichotomized into desired outcomes at 3 months: >70% isometric knee extension LSI, > 20 repetitions on anterior stepdown test (AST), > 90% LSI Y Balance. At RTP testing, isokinetic knee extension strength data was categorized into >89% LSI at 3 speeds (300, 180, 60°/sec). Chi square testing and odds ratio statistics were used to examine association and its magnitude. Results: 63 patients met inclusion criteria (38 females; 15.37±1.66 years old). >70% LSI isometric knee extension strength at 3 months showed a significant association (Table 2) and demonstrated the strongest odds of having >89% LSI on isokinetic strength tests at all 3 speeds at RTP with 180°/sec being the highest (OR=14.5; 95% CI=4.25,49.43; p= <0.001). Performance on AST showed a significant association (χ2 (1, n=63) = 17.00, p <0.001), and highest odds at 180°/sec (OR=4.61; 95% CI = 1.59, 13.39, p=<0.001) and 60°/sec (OR= 3.07; 95% CI = 1.10, 8.63, p= 0.04). Combination of performance on isometric strength tests and AST showed a significant association to isokinetic strength at all three speeds, but less predictive then isometrics in isolation. (Table 2). There was no significant relationship between YBR LSI at 3 months and isokinetic strength at 6 months. Conclusion: Standardized strength testing early in rehabilitation can help identify patients that will successfully complete RTP testing. Our results suggest that isometric knee extension strength and timed anterior stepdown test provide meaningful clinical information early in the rehabilitation process. This data also suggests that the use of YBAL for predicting isokinetic strength performance is limited. [Table: see text][Table: see text]

An ICA Algorithm Based on Symmetric and Asymmetric Generalized Gaussian Model

2011 ◽  
Vol 204-210 ◽  
pp. 470-475
Author(s):  
Feng Zhao ◽  
Yun Jie Zhang ◽  
Min Cai
Keyword(s):  
Independent Component Analysis ◽  
Gradient Method ◽  
Gaussian Model ◽  
Component Analysis ◽  
Independent Component ◽  
Blind Signal Separation ◽  
Natural Gradient ◽  
Analysis Model ◽  
Practical Applications ◽  
Source Signal

Maximum likelihood estimation is a very popular method to estimate the independent component analysis model because of good performance. Independent component analysis algorithm (the natural gradient method) based on this method is widely used in the field of blind signal separation. It potentially assumes that the source signal was symmetrical distribution, in fact in practical applications, source signals may be asymmetric. This article by distinguishing that the source signal is symmetrical or asymmetrical, proposes an improved natural gradient method based on symmetric generalized Gaussian model (People usually call generalized Gaussian model) and asymmetric generalized Gaussian model. The random mixed-signal simulation results show that the improved algorithm is better than the natural gradient separation method.

scholarly journals Physical Structure Induced Hydrophobicity Analyzed from Electrospinning and Coating Polyvinyl Butyral Films

2019 ◽  
Vol 2019 ◽  
pp. 1-5 ◽  
Author(s):  
Shuo Chen ◽  
Guo-Sai Liu ◽  
Hong-Wei He ◽  
Cheng-Feng Zhou ◽  
Xu Yan ◽  
...  
Keyword(s):  
Surface Structure ◽  
Critical Role ◽  
Film Surface ◽  
Polyvinyl Butyral ◽  
Physical Structure ◽  
Surface Wettability ◽  
Practical Applications ◽  
Physical Surface ◽  
Film Forming ◽  
Surface Morphologies

Surface wettability of a film plays a critical role in its practical applications. To control the surface wettability, modification on the physical surface structures has been a useful method. In this paper, we reported the controlling physical surface structure of polyvinyl butyral (PVB) films by different film-forming methods, spin-coating, bar-coating, and electrospinning. The wettability of these PVB films was examined, and the surface morphologies and roughness were investigated. The results indicated that coating PVB films were hydrophilic, while electrospun films were hydrophobic. The physical surface structure was the key role on the interesting transition of their surface wettability. Theoretical analyses on these results found that the coating PVB films showed different mechanism with electrospun ones. These results may help to find the way to control the PVB film surface wettability and then guide for applications.

Assessment of post-heat behavior of cement mortar incorporating silica fume and granulated blast-furnace slag

2020 ◽  
Vol 11 (2) ◽  
pp. 221-246
Author(s):  
Ghasem Pachideh ◽  
Majid Gholhaki
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
Blast Furnace Slag ◽  
Strength Test ◽  
Content Type ◽  
Granulated Blast Furnace Slag ◽  
Cement Mortars ◽  
Strength Tests ◽  
Pozzolanic Materials ◽  
Furnace Slag

Purpose With respect to the studies conducted so far and lack of researches on the post-heat behavior of cement mortars containing pozzolanic materials, the purpose of this paper is to investigate the post-heat mechanical characteristics (i.e. compressive, tensile and flexural strength) of cement mortars containing granulated blast-furnace slag (GBFS) and silica fume (SF). In doing so, selected temperatures include 25, 100, 250, 500, 700 and 9000c. Last, the X-ray diffraction test was conducted to study the microstructure of mixtures and subsequently, the results were presented as power-one mathematical relations. Design/methodology/approach Totally, 378 specimens were built to conduct flexural, compressive and tensile strength tests. Accordingly, these specimens include cubic and prismatic specimens with dimensions of 5 × 5 × 5 cm and 16 × 4 × 4 cm, respectively, to conduct compressive and flexural strength tests together with briquette specimen used for tensile strength test in which cement was replaced by 7, 14 and 21 per cent of SF and GBFS. To study the effect of temperature, the specimens were heated. In this respect, they were heated with a rate of 5°C/min and exposed to temperatures of 25 (ordinary temperature), 100, 250, 500, 700 and 900°C. Findings On the basis of the results, the most profound effect of using GBFS and SF, respectively, takes place in low (up to 250°C) and high (500°C and greater degrees) temperatures. Quantitatively, the compressive, tensile and flexural strengths were enhanced by 73 and 180 per cent, 45 and 100 per cent, 106 and 112 per cent, respectively, in low and high temperatures. In addition, as the temperature elevates, the particles of specimens containing SF and GBFS shrink less in size compared to the reference specimen. Originality/value The specimens were cured according to ASTMC192 after 28 days placement in the water basin. First, in compliance with what has been specified by the mix design, the mortar, including pozzolanic materials and superplasticizer, was prepared and then, the sampling procedure was conducted on cubic specimens with dimension of 5 × 5 × 5 mm for compressive strength test, prismatic specimens with dimensions of 16 × 4 × 4 mm for flexural strength test and last, briquette specimens were provided to conduct tensile strength tests (for each temperature and every test, three specimens were built).

scholarly journals Application of UHF Sensors in Power System Equipment for Partial Discharge Detection: A Review

Sensors ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 1029 ◽  
Author(s):  
Hua Chai ◽  
B.T. Phung ◽  
Steve Mitchell
Keyword(s):  
Power System ◽  
Electromagnetic Interference ◽  
Early Stage ◽  
Signal To Noise Ratio ◽  
Partial Discharge ◽  
Critical Role ◽  
Physical Structure ◽  
High Signal ◽  
Practical Applications ◽  
Electrical Stress

Condition monitoring of an operating apparatus is essential for lifespan assessment and maintenance planning in a power system. Electrical insulation is a critical aspect to be monitored, since it is susceptible to failure under high electrical stress. To avoid unexpected breakdowns, the level of partial discharge (PD) activity should be continuously monitored because PD occurrence can accelerate the aging process of insulation in high voltage equipment and result in catastrophic failure if the associated defects are not treated at an early stage. For on-site PD detection, the ultra-high frequency (UHF) method was employed in the field and showed its effectiveness as a detection technique. The main advantage of the UHF method is its immunity to external electromagnetic interference with a high signal-to-noise ratio, which is necessary for on-site monitoring. Considering the detection process, sensors play a critical role in capturing signals from PD sources and transmitting them onto the measurement system. In this paper, UHF sensors applied in PD detection were comprehensively reviewed. In particular, for power transformers, the effects of the physical structure on UHF signals and practical applications of UHF sensors including PD localization techniques were discussed. The aim of this review was to present state-of-the-art UHF sensors in PD detection and facilitate future improvements in the UHF method.

scholarly journals E1 Signal Processing of the Galileo System in the Navigation Receiver

2021 ◽  
Vol 23 (3) ◽  
pp. E46-E55
Author(s):  
Lucjan Setlak ◽  
Rafał Kowalik
Keyword(s):  
Signal Processing ◽  
Navigation System ◽  
Model Simulation ◽  
Research Problem ◽  
Problem Analysis ◽  
Analysis Model ◽  
Practical Applications ◽  
Navigation Data ◽  
The Subject ◽  
Research Tools

The subject of this article are issues related to the navigation system in the field of analyzing the processed signal in the GNSS system receiver. The main purpose of the work is to discuss the Galileo E1 signal processing methods in the GNSS navigation system receiver, supported by adapted research tools in terms of solving the research problem (analysis, model, simulation tests) and the mathematical apparatus used. Key studies are concentrated around the process of generating the navigation data, dispersing sequences and signal modulation. Thus, when designing a receiver, it is better to use the simulation signals than the real ones, since one can get more control over the properties of the received signal. In the final part of the work, in accordance with the subject of research, based on the developed appropriate research tools, observations and final conclusions were formulated, which have practical applications.

Analysis of Flexibility and Stability of Crane Telescopic Boom with Elastic Restraint and Second-Order Effect

2013 ◽  
Vol 774-776 ◽  
pp. 109-113
Author(s):  
Liang Du ◽  
Nian Li Lu ◽  
Peng Lan
Keyword(s):  
Stability Analysis ◽  
Differential Equations ◽  
Boundary Conditions ◽  
Order Effect ◽  
Second Order ◽  
Analysis Model ◽  
Characteristic Equations ◽  
Lateral Deflection ◽  
Practical Applications ◽  
Vertical Stability

The cylinder support crane telescopic booms deformation and stability analysis model in the lifting plane is equivalent with the multistep column with elastic restraint. To analyze the lateral flexibility and vertical stability of the telescopic booms with elastic restraint accurately, this paper established the deflection differential equations of multi-sectioned telescopic booms with second-order effect, introduced proper boundary conditions, obtained the precise recurrence lateral deflection differential equations and the buckling characteristic equations of arbitrary sectioned telescopic booms, and some practical applications of the buckling characteristic equations were presented. Took certain five-sectioned telescopic booms as example, by comparing the results with ANSYS method, the accuracy of the equations deduced in this paper was verified.

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