Journal articles: 'Degradation modes'

1

Jordan, Dirk C., Timothy J. Silverman, John H. Wohlgemuth, Sarah R. Kurtz, and Kaitlyn T. VanSant. "Photovoltaic failure and degradation modes." Progress in Photovoltaics: Research and Applications 25, no. 4 (January 30, 2017): 318–26. http://dx.doi.org/10.1002/pip.2866.

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Haghighi, Firoozeh, and Mikhail Nikulin. "On the linear degradation model with multiple failure modes." Journal of Applied Statistics 37, no. 9 (September 2010): 1499–507. http://dx.doi.org/10.1080/02664760903055434.

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O'Kane, Simon E. J., Niall Kirkaldy, Gregory James Offer, and Monica Marinescu. "Lithium-Ion Battery Degradation: How to Diagnose It." ECS Meeting Abstracts MA2022-01, no. 2 (July 7, 2022): 396. http://dx.doi.org/10.1149/ma2022-012396mtgabs.

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Many different degradation mechanisms occur in lithium-ion batteries, all of which interact with one another [1]. However, there are few fewer observable consequences of degradation than there are mechanisms [2]. It is possible to measure the different degradation modes: loss of lithium inventory (LLI), loss of active material (LAM), impedance change and stoichiometric drift [3]. It is not always possible to link these observable consequences of degradation to any particular mechanism or combination of mechanisms. Many models of degradation exist [4], but these models have many parameters that cannot be measured directly. A recent modelling study [5] found the number of parameters that the model is sensitive to is greater than the number of observable degradation modes. However, the same model [5], despite including just four degradation mechanisms, found five possible degradation pathways a battery can follow. The model was built so that more mechanisms can easily be added later, so more pathways will be found. In this work, a new approach to diagnosing battery degradation is proposed, based on these pathways. Experimental data for the degradation modes can be identified as being consistent with a particular pathway. Once the correct pathway is found, the parameters that particular pathway is sensitive to can be fit to the data, feeding back into the model. [1] Jacqueline Edge et al., Phys. Chem.: Chem. Phys. vol. 23, pp. 8200-8221, 2021. [2] Christoph Birkl et al., Journal of Power Sources vol. 341, pp. 373-386, 2017. [3] Matthieu Dubarry et al., J. Electrochem. En. Conv. Stor. vol. 17, pp. 044701, 2020. [4] Jorn Reniers et al., J. Electrochem. Soc. vol. 166 pp. A3189-A3200, 2019. [5] Simon O’Kane et al., Phys. Chem.: Chem. Phys., submitted, 2022. https://arxiv.org/abs/2112.02037

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Dubarry, Matthieu, Cyril Truchot, and Bor Yann Liaw. "Synthesize battery degradation modes via a diagnostic and prognostic model." Journal of Power Sources 219 (December 2012): 204–16. http://dx.doi.org/10.1016/j.jpowsour.2012.07.016.

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Jao, Ting-Chu, Guo-Bin Jung, Shih-Tsung Ke, Pei-Hung Chi, and Shih-Hung Chan. "Diagnosis of PTFE-Nafion MEA degradation modes by an accelerated degradation technique." International Journal of Energy Research 35, no. 14 (December 13, 2010): 1274–83. http://dx.doi.org/10.1002/er.1797.

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Zhao, Chengwei, Sunia Tanweer, Jian Li, Min Lin, Xiang Zhang, and Yang Liu. "Nonlinear Guided Wave Tomography for Detection and Evaluation of Early-Life Material Degradation in Plates." Sensors 21, no. 16 (August 16, 2021): 5498. http://dx.doi.org/10.3390/s21165498.

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In this paper, the possibility of using nonlinear ultrasonic guided waves for early-life material degradation in metal plates is investigated through both computational modeling and study. The analysis of the second harmonics of Lamb waves in a free boundary aluminum plate, and the internal resonance conditions between the Lamb wave primary modes and the second harmonics are investigated. Subsequently, Murnaghan’s hyperelastic model is implemented in a finite element (FE) analysis to study the response of aluminum plates subjected to a 60 kHz Hanning-windowed tone burst. Different stages of material degradation are reflected as the changes in the third order elastic constants (TOECs) of the Murnaghan’s model. The reconstructed degradations match the actual ones well across various degrees of degradation. The effects of several relevant factors on the accuracy of reconstructions are also discussed.

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Tuttle, D. L., and W. A. Dunn. "Divergent modes of autophagy in the methylotrophic yeast Pichia pastoris." Journal of Cell Science 108, no. 1 (January 1, 1995): 25–35. http://dx.doi.org/10.1242/jcs.108.1.25.

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The budding yeast Pichia pastoris responds to methanolic media by synthesizing high levels of cytosolic enzymes (e.g. formate dehydrogenase) and peroxisomal enzymes (e.g. alcohol oxidase), which are necessary to assimilate this carbon source. Major alterations in cellular metabolism are initiated upon a shift in carbon source to ethanol or glucose. These alterations require the synthesis of new proteins and the rapid degradation of those enzymes no longer needed for methanol utilization. In this study, we have measured cytosolic and peroxisomal enzyme activities and examined the fate of morphologically distinct peroxisomes to assess the degradative response of this yeast during nutrient adaptation. Utilizing biochemical, morphological and genetic approaches, we have shown that there exist in P. pastoris at least two pathways for the sequestration of peroxisomes into the vacuole for degradation. The ethanol-induced pathway is independent of protein synthesis and includes an intermediate stage in which individual peroxisomes are sequestered into autophagosomes by wrapping membranes, which then fuse with the vacuole. This process is analogous to macroautophagy. The glucose-induced pathway invokes the engulfment of clusters of peroxisomes by finger-like protrusions of the vacuole by a process analogous to microautophagy. Unlike ethanol adaptation, glucose stimulated the degradation of formate dehydrogenase as well. Peroxisomes remained outside the vacuoles of glucose-adapted cycloheximide-treated normal cells, suggesting that protein synthesis is required for peroxisome entry into the yeast vacuole. Two complementary mutants (gsa1 and gsa2) that are unable to degrade peroxisomes or formate dehydrogenase during glucose adaptation were isolated. The mutated gene products appear to function in one or more events upstream of degradation within the vacuole, since ethanol-induced peroxisome degradation proceeded normally in these mutants and peroxisomes were found outside the vacuoles of glucose-adapted gsa2 cells. Mutants lacking vacuolar proteinases A and B were unable to degrade alcohol oxidase or formate dehydrogenase during ethanol or glucose adaptation. Peroxisomes were found to accumulate within the vacuoles of these proteinase mutants during adaptation. Combined, the results suggest that there exist in Pichia pastoris two independent pathways for the sequestration of peroxisomes into the vacuole, the site of degradation.

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Huang, Jack Jia-Sheng, C. K. Wang, and Yu-Heng Jan. "Three Cases of Gradual Degradation Mode Analysis of Semiconductor Laser Diodes." Modern Applied Science 15, no. 6 (October 26, 2021): 27. http://dx.doi.org/10.5539/mas.v15n6p27.

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Semiconductor laser diodes are important components for various applications such as 5G wireless, datacenter, passive optical network, and aerospace applications. High reliability has emerged to be the universal requirement for all optical applications. To achieve high reliability, fundamental understanding of the laser degradation behavior is crucial. In this paper, we study three cases of gradual degradataion modes of laser diodes including (1) Pattern-A that is associated with threshold current change only, (2) Pattern-B that involve both threshold current and power changes, and (3) Pattern-C that is associated with merely power change. We have instituted reliability equations for the degradation processes. The new reliability models could provide estimation on the laser end-of-life based on the degradation rate and device performance specification.

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Zhao, Xiujie, Jianyu Xu, and Bin Liu. "Accelerated Degradation Tests Planning With Competing Failure Modes." IEEE Transactions on Reliability 67, no. 1 (March 2018): 142–55. http://dx.doi.org/10.1109/tr.2017.2761025.

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Jiménez, Juan. "Laser diode reliability: crystal defects and degradation modes." Comptes Rendus Physique 4, no. 6 (July 2003): 663–73. http://dx.doi.org/10.1016/s1631-0705(03)00097-5.

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Kornitzer, Daniel, and Aaron Ciechanover. "Modes of regulation of ubiquitin-mediated protein degradation." Journal of Cellular Physiology 182, no. 1 (January 2000): 1–11. http://dx.doi.org/10.1002/(sici)1097-4652(200001)182:1<1::aid-jcp1>3.0.co;2-v.

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Jordan, Dirk C., Timothy J. Silverman, Bill Sekulic, and Sarah R. Kurtz. "PV degradation curves: non-linearities and failure modes." Progress in Photovoltaics: Research and Applications 25, no. 7 (September 30, 2016): 583–91. http://dx.doi.org/10.1002/pip.2835.

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13

Yan, Jihong, and Jay Lee. "Degradation Assessment and Fault Modes Classification Using Logistic Regression." Journal of Manufacturing Science and Engineering 127, no. 4 (July 22, 2004): 912–14. http://dx.doi.org/10.1115/1.1962019.

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Real-time health monitoring of industrial components and systems that can detect, classify and predict impending faults is critical to reducing operating and maintenance cost. This paper presents a logistic regression based prognostic method for on-line performance degradation assessment and failure modes classification. System condition is evaluated by processing the information gathered from controllers or sensors mounted at different points in the system, and maintenance is performed only when the failure∕malfunction prognosis indicates instead of periodic maintenance inspections. The wavelet packet decomposition technique is used to extract features from non-stationary signals (such as current, vibrations), wavelet package energies are used as features and Fisher’s criteria is used to select critical features. Selected features are input into logistic regression (LR) models to assess machine performance and identify possible failure modes. The maximum likelihood method is used to determine parameters of LR models. The effectiveness and feasibility of this methodology have been illustrated by applying the method to a real elevator door system.

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Li, Bei, Zhi Jia Xie, Wen Tao Jin, and Hui Meng Ma. "Study on Partial Degradation Operation Modes of VRB-ESS." Advanced Materials Research 512-515 (May 2012): 1074–78. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.1074.

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Vanadium Redox Flow Battery (VRB) holds unique characteristic as the power and capacity of the physical structure of independent design, which determines VRB different from other battery types in operating characteristics by taking unique operation modes under the circumstance of module degradation or failure in some cases. Paper focuses on how to ride through the case of VRB system with partial degradation or failure during the normal operational conditions, launched a comprehensive experimental study and theoretical analysis. The paper analyzes several situations from the point of view of the battery physical components which should lead VRB system partial failed, and simulated the battery partial degradation or failure by experimental means, and carried out two operation modes to respond to different partial failure situations, which including the use of lower rated power and the use of times rated power. Study proved that those two modes operated in the case of VRB partial failure conditions, has no significant effect to VRB Energy Storage System (ESS) efficiency, as well as be helpful to improve a higher reliability of VRB energy storage system. This paper takes the lead in studying the operational characteristics of VRB- ESS from the angle of partial degradation or failure conditions, which has practical engineering significance for developing VRB -ESS demonstration.

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Guerin, ChloÉ, Vincent Huard, and Alain Bravaix. "The Energy-Driven Hot-Carrier Degradation Modes of nMOSFETs." IEEE Transactions on Device and Materials Reliability 7, no. 2 (June 2007): 225–35. http://dx.doi.org/10.1109/tdmr.2007.901180.

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Tomantschger, Klaus, Robert Findlay, Michael Hanson, Karl Kordesch, and Supramaniam Srinivasan. "Degradation modes of alkaline fuel cells and their components." Journal of Power Sources 39, no. 1 (1992): 21–41. http://dx.doi.org/10.1016/0378-7753(92)85003-s.

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Neoh, K. G., E. T. Kang, and K. L. Tan. "Degradation behavior of polyanilines with different modes of doping." Polymer Degradation and Stability 43, no. 1 (January 1994): 141–47. http://dx.doi.org/10.1016/0141-3910(94)90236-4.

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Nguyen, Tinh, Xiaohong Gu, Mark Vanlandingham, Eric Byrd, Rose Ryntz, and Jonathan W. Martin. "Degradation modes of crosslinked coatings exposed to photolytic environment." Journal of Coatings Technology and Research 10, no. 1 (November 28, 2012): 1–14. http://dx.doi.org/10.1007/s11998-012-9455-1.

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Qiao, Longxue, Yaohua Du, Feng Chen, Jinlong Wu, and Taihu Wu. "Optimization analysis of non-contact ultrasonic degradation system based on synchronous resonance of multiple modes." Journal of Vibroengineering 18, no. 2 (March 31, 2016): 1227–42. http://dx.doi.org/10.21595/jve.2016.16411.

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To solve the defects of low degradation efficiency and high cross-contamination risk in the conventional ultrasonic processor, a non-contact ultrasonic degradation system was developed. Through finite-element modal analysis, the natural frequencies of the first ten modes of the diaphragm with dome-shaped structure were found to have a ladder-like distribution, which provides a possibility to utilize the synchronous resonance of multiple modes. The effects of curvature radius, thickness and preload force on the synchronous resonance of multiple modes are studied using the control variate method, and then the structural parameters and the preload force are optimized. Based on these results, the diaphragm was manufactured, the experimental platform of the non-contact ultrasonic degradation was established, and its degradation efficiency was evaluated. The experimental results proved that the non-contact ultrasonic degradation system was able to effectively degrade Bacillus atrophaeus.

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Xia, Qing, Zong Jie Cao, Yuan Da Wang, and Peng Sun. "Accelerated Degradation Modeling and Statistical Analysis of MEMS Device Based on Competing Failure." Key Engineering Materials 531-532 (December 2012): 580–83. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.580.

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Traditional reliability analysis of MEMS devices is based on only one failure mode, but paroxysmal failure and degradation failure are simultaneous on one MEMS device which is called as competing failure modes. Accelerated degradation modeling and parameter estimation based on competing failure modes are elementary contents of reliability analysis, in which paroxysmal failure and degradation failure are integrated in the process of educing reliability function, and elementary theories of reliability and statistics are used. The method of accelerated degradation modeling and parameter estimation is proved to be precise in a simulation of accelerated life test on a kind of MEMS device which have the two failure modes: paroxysmal failure and degradation failure, and they are have relations with stress variable: current.

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Li, Longteng, Bo Jing, and Jiaxing Hu. "Study on Establishing Degradation Model of Chip Solder Joint Material under Coupled Stress." Materials 13, no. 8 (April 12, 2020): 1813. http://dx.doi.org/10.3390/ma13081813.

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The chip is the core component of the integrated circuit. Degradation and failure of chip solder joints can directly lead to function loss of the integrated circuit. In order to establish the degradation model of chip solder joints under coupled stress, this paper takes quad flat package (QFP) chip solder joints as the study object. First, solder joint degradation data and failure samples were obtained through fatigue tests under coupled stress. Three types of micro failure modes of solder joints were obtained by scanning electron microscope (SEM) analysis and finite element model (FEM) simulation results. Second, the characterization of degradation data was obtained by the principal component of Mahalanobis distance (PCMD) algorithm. It is found that solder joint degradation is divided into three stages: strain accumulation stage, crack propagation stage, and failure stage. Later, Coffin–Manson model and Paris model were modified based on the PCMD health index and strain simulation. The function relationship between strain accumulation time, crack propagation time, and strain was determined, respectively. Solder joint degradation models at different degradation stage were established. Finally, through strain simulation, the models can predict the strain accumulation time and failure time effectively under each failure mode, and their prediction accuracy is above 85%.

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Ouladsine, Radouane, Rachid Outbib, and Mohamed Bakhouya. "The PV Corrosion Fault Prognosis Based on Ensemble Kalman Filter." International Journal of Photoenergy 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/1825931.

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The degradation of photovoltaic (PV) modules remains a major concern on the control and the development of the photovoltaic field, particularly, in regions with difficult climatic conditions. The main degradation modes of the PV modules are corrosion, discoloration, glass breaks, and cracks of cells. However, corrosion and discoloration remain the predominant degradation modes that still require further investigations. In this paper, a model-based PV corrosion prognostic approach, based on an ensemble Kalman filter (EnKF), is introduced to identify the PV corrosion parameters and then estimate the remaining useful life (RUL). Simulations have been conducted using measured data set, and results are reported to show the efficiency of the proposed approach.

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Nakahara, Masao. "Degradation/Damage Modes and their Control Measures for Stainless Steel Components in Chemical Plants." Advanced Materials Research 794 (September 2013): 681–90. http://dx.doi.org/10.4028/www.scientific.net/amr.794.681.

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Safe and continuous operation of chemical plants is the most important issue for sustainability of chemical enterprises. The control and prevention of degradation/damage on components used in chemical plants are indispensable for this purpose. Although varied types of material, such as stainless steels, Ni-based alloys and reactive metals, are in use to control these phenomena in plants, various cases of degradation/damage have actually been experienced and the accidents caused by such degradation have occasionally been reported. In order to prevent such uncontrolled degradation, it is thought necessary to predict the likelihood of degradation of materials under actual operating conditions, to use compatible materials, to detect the degradation by inspection in advance and to apply proper countermeasures based on realistic life estimation of the plant concerned. In order to follow these processes properly, extensive accumulation and orderly organization of knowledge about the mechanisms on degradation/damages, characteristics of materials, inspection technics and methods of plant life estimation are thought of vital importance. As stainless steel is the commonly used material in chemical plants, sufficient accumulation of informattion and knowledge about the stainless steel components to be used is considered the most important subject to prevent the degradation/damage in chemical plants. This paper enumerates the characteristics of commonly encountered modes of degradation with stainless steel components in chemical plants and presents some cases of the degradation/damage on stainless steel equipment in plants, together with control measures required to prevent such degradation. The present-day problems of materials engineering relating to the reliability of chemical plants and the countermeasures against degradation/damage are also presented.

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Fei, Teng, and Hao-Wei Wang. "Reliability Demonstration Method for Competing Failure System." International Journal of Reliability, Quality and Safety Engineering 27, no. 04 (April 7, 2020): 2050015. http://dx.doi.org/10.1142/s0218539320500151.

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In order to improve the accuracy of reliability assessment for the system with multiple failure modes, a reliability modeling method based on the s-dependent competing risk of degradation failures and traumatic failures was proposed. A condition space model was applied to evaluate the degradation degree of system by fusing multivariate degradation data, and then Gamma process was utilized to establish the degradation failure model of system. A conditional Weibull distribution was used to establish the traumatic failure model of system. The reliability model based on dependent competing risk was established by assuming that the probability of traumatic failure depends on the degradation degree of system. An illustrative example was provided to validate the effectiveness of the proposed method.

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Hao, Hui Bing, and Chun Su. "Reliability Analysis on Competitive Failure Processes under Multiple Failure Modes." Applied Mechanics and Materials 442 (October 2013): 257–63. http://dx.doi.org/10.4028/www.scientific.net/amm.442.257.

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In this article, a new multiple competing failure models proposed, in which multiple degradation processes and random shocks are considered. The shocks have a significant impact on system reliability, and the system reliability under not considering the impact of shocks is much higher than the impact of shocks is considered. In addition, the influences of the correlation among different degradation processes are also considered in this article. We can find that the reliability with considering the dependent case is higher than the independent case reliability. Thus the dependence of the two degradation processes is non-negligible. A numerical example with reliability analysis and sensitivity analysis is discussed to illustrate the proposed the new model.

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Meng, Xingang, Yuanjun Guo, Yihui Wang, Shijun Fan, Kaiqi Wang, and Wenhua Han. "A Systematic Review of Photolysis and Hydrolysis Degradation Modes, Degradation Mechanisms, and Identification Methods of Pesticides." Journal of Chemistry 2022 (June 6, 2022): 1–13. http://dx.doi.org/10.1155/2022/9552466.

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The degradation modes and characteristics of different pesticides were introduced. In addition, this paper also describes the degradation mechanism of different pesticides, classifies, and summarizes the methods of degradation products identification. For the sake of human life health and better biological environment, we should have a familiar knowledge of the natural degradation of pesticides and understand the photo-hydrolysis and its influencing factors (temperature, pH, light, etc.). Through the degradation mechanism and influencing factors, the degradation time could be accelerated and it also provides a theoretical basis and basic support for the treatment of pesticide residues in the future.

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Jorgenson, M. T., and T. E. Osterkamp. "Response of boreal ecosystems to varying modes of permafrost degradation." Canadian Journal of Forest Research 35, no. 9 (September 1, 2005): 2100–2111. http://dx.doi.org/10.1139/x05-153.

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Permafrost degradation associated with a warming climate is second only to wildfires as a major disturbance to boreal forests. Permafrost temperatures have risen to 4 °C since the “Little Ice Age”, resulting in widespread thawing of permafrost. The mode of permafrost degradation is highly variable, and its topographic and ecological consequences depend on the interaction of slope position, soil texture, hydrology, and ice content. We partitioned this variability into 16 primary modes: (1) thermokarst lakes from lateral thermomechanical erosion; (2) thermokarst basins after lake drainage; (3) thaw sinks from subsurface drainage of lakes; (4) glacial thermokarst of ice-cored moraines; (5) linear collapse-scar fens associated with shallow groundwater movement; (6) round isolated collapse-scar bogs from slow lateral degradation; (7) small round isolated thermokarst pits from surface thawing; (8) polygonal thermokarst mounds from advanced ice-wedge degradation; (9) mixed thermokarst pits and polygons from initial ice-wedge degradation; (10) irregular thermokarst mounds from thawing of ice-poor silty soils; (11) sinkholes and pipes resulting from groundwater flow; (12) thermokarst gullies and water tracks from surface-water flow; (13) thaw slumps related to slope failure and thawing; (14) thermo-erosional niches from water undercutting of ice-rich shores; (15) collapsed pingos from thawing of massive ice in pingos; and (16) nonpatterned ground from thawing of ice-poor soils. These modes greatly influence how thermokarst changes or disrupts the ground surface, ecosystems, human activities, infrastructure, and the fluxes of energy, moisture, and gases across the landair interface.

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Sardanyés, Josep, Fernando Martínez, José-Antonio Daròs, and Santiago F. Elena. "Dynamics of alternative modes of RNA replication for positive-sense RNA viruses." Journal of The Royal Society Interface 9, no. 69 (September 7, 2011): 768–76. http://dx.doi.org/10.1098/rsif.2011.0471.

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We propose and study nonlinear mathematical models describing the intracellular time dynamics of viral RNA accumulation for positive-sense single-stranded RNA viruses. Our models consider different replication modes ranging between two extremes represented by the geometric replication (GR) and the linear stamping machine replication (SMR). We first analyse a model that quantitatively reproduced experimental data for the accumulation dynamics of both polarities of turnip mosaic potyvirus RNAs. We identify a non-degenerate transcritical bifurcation governing the extinction of both strands depending on three key parameters: the mode of replication ( α ), the replication rate ( r ) and the degradation rate ( δ ) of viral strands. Our results indicate that the bifurcation associated with α generically takes place when the replication mode is closer to the SMR, thus suggesting that GR may provide viral strands with an increased robustness against degradation. This transcritical bifurcation, which is responsible for the switching from an active to an absorbing regime, suggests a smooth (i.e. second-order), absorbing-state phase transition. Finally, we also analyse a simplified model that only incorporates asymmetry in replication tied to differential replication modes.

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Behzad, Mehdi, Sajjad Feizhoseini, Hesam Addin Arghand, Ali Davoodabadi, and David Mba. "Failure Threshold Determination of Rolling Element Bearings Using Vibration Fluctuation and Failure Modes." Applied Sciences 11, no. 1 (December 26, 2020): 160. http://dx.doi.org/10.3390/app11010160.

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One of the challenges in predicting the remaining useful life (RUL) of rolling element bearings (REBs) is determining a proper failure threshold (FT). In the literature, the FT is usually assumed to be a constant value of an extracted feature from the vibration signals. In this study, a degradation indicator was extracted to describe damage to REBs by applying principal component analysis (PCA) to their run-to-failure data. The relationship between this degradation indicator and the vibration peak was represented through a joint probability distribution using statistical copula models. The FT was proposed as a probability distribution based on the fluctuation increase in the vibration trend. A set of run-to-failure tests was conducted. Applying the proposed method to this dataset led to various FTs for the different failure modes that occurred. It is shown that, for inner race degradation, a higher FT can be assumed than for rolling element degradation. This could help extend the lives of REBs regarding the degrading elements. A dataset for an industrial machine was also analyzed and it is shown that the proposed model estimated a reasonable and proper FT in an actual case study.

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Fu, Yue, Li Bin Zhao, and Jian Yu Zhang. "Fatigue Stiffness Degradation Behaviour of Woven Composite π Joint." Applied Mechanics and Materials 275-277 (January 2013): 1714–17. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.1714.

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Fatigue stiffness degradation behaviour of woven composite π joint subjected to tensile-tensile cycle loading is studied. Because of the complex structural configuration of woven composite π joints and a variety of failure modes, there exhibited four stiffness degradation modes in fatigue test. For example, stable slight reduction mode, abruptly decreasing mode, step decreasing mode and constant stiffness mode. Each stiffness degradation mode has a corresponding failure mode in fatigue test.

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Sun, Hao, Bo Jiang, Heze You, Bojian Yang, Xueyuan Wang, Xuezhe Wei, and Haifeng Dai. "Quantitative Analysis of Degradation Modes of Lithium-Ion Battery under Different Operating Conditions." Energies 14, no. 2 (January 10, 2021): 350. http://dx.doi.org/10.3390/en14020350.

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The degradation mode is of great significance for reducing the complexity of research on the aging mechanisms of lithium-ion batteries. Previous studies have grouped the aging mechanisms into three degradation modes: conductivity loss (CL), loss of lithium inventory (LLI) and loss of active material (LAM). Combined with electrochemical impedance spectroscopy (EIS), degradation modes can be identified and quantified non-destructively. This paper aims to extend the application of this method to more operating conditions and explore the impact of external factors on the quantitative results. Here, we design a quantification method using two equivalent circuit models to cope with the different trends of impedance spectra during the aging process. Under four conditions, the changing trends of the quantitative values of the three degradation modes are explored and the effects of the state of charge (SoC) and excitation current during EIS measurement are statistically analyzed. It is verified by experiments that LLI and LAM are the most critical aging mechanisms under various conditions. The selection of SoC has a significant effect on the quantitative results, but the influence of the excitation current is not obvious.

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Sun, Hao, Bo Jiang, Heze You, Bojian Yang, Xueyuan Wang, Xuezhe Wei, and Haifeng Dai. "Quantitative Analysis of Degradation Modes of Lithium-Ion Battery under Different Operating Conditions." Energies 14, no. 2 (January 10, 2021): 350. http://dx.doi.org/10.3390/en14020350.

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The degradation mode is of great significance for reducing the complexity of research on the aging mechanisms of lithium-ion batteries. Previous studies have grouped the aging mechanisms into three degradation modes: conductivity loss (CL), loss of lithium inventory (LLI) and loss of active material (LAM). Combined with electrochemical impedance spectroscopy (EIS), degradation modes can be identified and quantified non-destructively. This paper aims to extend the application of this method to more operating conditions and explore the impact of external factors on the quantitative results. Here, we design a quantification method using two equivalent circuit models to cope with the different trends of impedance spectra during the aging process. Under four conditions, the changing trends of the quantitative values of the three degradation modes are explored and the effects of the state of charge (SoC) and excitation current during EIS measurement are statistically analyzed. It is verified by experiments that LLI and LAM are the most critical aging mechanisms under various conditions. The selection of SoC has a significant effect on the quantitative results, but the influence of the excitation current is not obvious.

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Costa, N., L. Sánchez, D. Anseán, and M. Dubarry. "Li-ion battery degradation modes diagnosis via Convolutional Neural Networks." Journal of Energy Storage 55 (November 2022): 105558. http://dx.doi.org/10.1016/j.est.2022.105558.

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Shokolenko, Inna N., Glenn L. Wilson, and Mikhail F. Alexeyev. "The “fast” and the “slow” modes of mitochondrial DNA degradation." Mitochondrial DNA 27, no. 1 (April 14, 2014): 490–98. http://dx.doi.org/10.3109/19401736.2014.905829.

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Horn, Q., and K. White. "Characterization of Degradation and Failure Modes in Lithium-ion Cells." Microscopy and Microanalysis 19, S2 (August 2013): 1842–43. http://dx.doi.org/10.1017/s1431927613011203.

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Wang, Ethan, Hsinjin Edwin Yang, Jerry Yen, Sunny Chi, and Carl Wang. "Failure Modes Evaluation of PV Module via Materials Degradation Approach." Energy Procedia 33 (2013): 256–64. http://dx.doi.org/10.1016/j.egypro.2013.05.066.

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Guerre, Catherine, Luc Rémy, and Régine Molins. "Alumina scale growth and degradation modes of a TBC system." Materials at High Temperatures 20, no. 4 (January 2003): 481–85. http://dx.doi.org/10.1179/mht.2003.056.

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Algül, Hana, Yusuke Tando, Michael Beil, Christoph K. Weber, Claus Von Weyhern, Günter Schneider, Guido Adler, and Roland M. Schmid. "Different modes of NF-κB/Rel activation in pancreatic lobules." American Journal of Physiology-Gastrointestinal and Liver Physiology 283, no. 2 (August 1, 2002): G270—G281. http://dx.doi.org/10.1152/ajpgi.00407.2001.

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The eukaryotic transcription factor nuclear factor-κB (NF-κB)/Rel is activated by a large variety of stimuli. It has been demonstrated that NF-κB/Rel is induced during the course of cerulein pancreatitis. Here, we show that NF-κB/Rel is differentially activated in pancreatic lobules. Cerulein induces NF-κB/Rel via activation of IκB kinase (IKK), which causes degradation of IκBα but not IκBβ. Tumor necrosis factor-α-mediated IKK activation leads to IκBα and IκBβ degradation. In contrast, oxidative stress induced by H2O2activates NF-κB/Rel independent of IKK activation and IκBα degradation; instead IκBα is phosphorylated on tyrosine. H2O2but not cerulein-mediated NF-κB/Rel activation can be blocked by stabilizing microtubules with Taxol. Inhibition of tubulin polymerization with nocodazole causes NF-κB/Rel activation in pancreatic lobules. These results propose three different pathways of NF-κB/Rel activation in pancreatic acinar cells. Furthermore, these data demonstrate that microtubules play a key role in IKK-independent NF-κB/Rel activation following oxidative stress.

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Lee, Munsu, Jinhyeong Park, Sun-Ik Na, Hyung Sik Choi, Byeong-Sik Bu, and Jonghoon Kim. "An Analysis of Battery Degradation in the Integrated Energy Storage System with Solar Photovoltaic Generation." Electronics 9, no. 4 (April 24, 2020): 701. http://dx.doi.org/10.3390/electronics9040701.

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Renewable energy generation and energy storage systems are considered key technologies for reducing greenhouse gas emissions. Energy system planning and operation requires more accurate forecasts of intermittent renewable energy resources that consider the impact of battery degradation on the system caused by the accumulation of charging and discharging cycles. In this study, a statistical model is presented for forecasting a day-ahead photovoltaic (PV) generation considering solar radiation and weather parameters. In addition, the technical performance of energy storage systems (ESS) should be evaluated by considering battery degradation that occurs during the charge and discharge cycles of the battery. In this study, a battery degradation model based on the data-driven method is used. Based on a suitable forecasting model, ESS scheduling is performed to charge the maximum amount of PV generation and discharge for the self-consumption of the customer load when PV generation ends. Since the battery is highly dependent on operating conditions such as depth of discharge, state of charge and temperature, two different ESS charge and discharge modes are proposed. From the simulation with the battery degradation model using parameters derived from experiments, we show that the battery is degraded along with charging cycles during testing periods. Variations in state of health are observed owing to the different characteristics of the battery according to the ESS operation modes, which are divided into the low and high SOC. Through experimental validation, it is proved that the state of charge (SOC), 0.45 is the optimal threshold that can determine the low and high SOC. Finally, the simulation results lead to the conclusion that the battery degradation in different operation modes should be taken into account to extend the end of life efficiently.

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Chu, Yuanbo, Zhaohui Yuan, Xuegong He, and Zhichao Dong. "Model Construction and Performance Degradation Characteristics of a Deflector Jet Pressure Servo Valve under the Condition of Oil Contamination." International Journal of Aerospace Engineering 2021 (February 27, 2021): 1–17. http://dx.doi.org/10.1155/2021/8840084.

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The deflector jet pressure servo valve is a kind of high-precision hydraulic component that can be widely used in the antiskid braking system of an aircraft. In actual service, it will be faced with extreme working conditions of gradual oil contamination, which will cause performance degradation and function maladjustment of the whole valve. To this end, the paper proposes a performance degradation characteristic analysis method. In which, firstly, the structural characteristics and working principle of the deflector jet pressure valve are analyzed; then, the entire dynamics model of the pressure valve is built using the braking cavity as the load blind cavity. Secondly, the two main failure modes induced by oil contamination such as erosion wear of pilot stage and stuck of slide valve stage’s valve core are determined based on the engineering experience, aimed at which the failure mechanism is analyzed; then, the sensitivity simulation model of the servo valve’s output pressure with respect to key degradation parameters is established and the sensitivity analysis is performed. Finally, combining the theoretical analysis with multiphysics simulation correction methods, the performance degradation model of the typical failure modes are established, and then, the performance degradation characteristics under dynamic contamination conditions are analyzed, which is combined with the failure threshold determined by the dynamics simulation to finish the service life prediction of the deflector jet servo valve.

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Larsson, Martin, Anna Niska, and Sigurdur Erlingsson. "Degradation of Cycle Paths—A Survey in Swedish Municipalities." CivilEng 3, no. 2 (March 23, 2022): 184–210. http://dx.doi.org/10.3390/civileng3020012.

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There is a need to move society in a sustainable direction. One way to contribute to this move is to change to more sustainable transport modes, such as cycling. To increase cycling, the infrastructure is important, and good quality cycle paths are needed. However, little is known about the degradation of cycle paths. This paper aims to investigate what modes of pavement distress are found on municipal cycle paths in Sweden, and what probable mechanisms lie behind such distress; these are determined based on questions from a state-of-practice survey, interviews, and a literature review. The main findings are that the most commonly stated distress modes are surface unevenness followed by longitudinal cracks, and the most commonly stated causes of distress are ageing, followed by structural interventions, and roots and vegetation. The results also show that for several distress modes, there are probable connections with climatic factors such as temperature and moisture, as well as with the population size of the urban areas. Objective data are needed regarding traffic load and the climatic factors that affect cycle paths, along with information on their structural design, to better understand their degradation.

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Lei, Shaojuan, Xiaodong Zhang, and Suhui Liu. "Dynamic Robustness of Open-Source Project Knowledge Collaborative Network Based on Opinion Leader Identification." Entropy 23, no. 9 (September 21, 2021): 1235. http://dx.doi.org/10.3390/e23091235.

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A large amount of semantic content is generated during designer collaboration in open-source projects (OSPs). Based on the characteristics of knowledge collaboration behavior in OSPs, we constructed a directed, weighted, semantic-based knowledge collaborative network. Four social network analysis indexes were created to identify the key opinion leader nodes in the network using the entropy weight and TOPSIS method. Further, three degradation modes were designed for (1) the collaborative behavior of opinion leaders, (2) main knowledge dissemination behavior, and (3) main knowledge contribution behavior. Regarding the degradation model of the collaborative behavior of opinion leaders, we considered the propagation characteristics of opinion leaders to other nodes, and we created a susceptible–infected–removed (SIR) propagation model of the influence of opinion leaders’ behaviors. Finally, based on empirical data from the Local Motors open-source vehicle design community, a dynamic robustness analysis experiment was carried out. The results showed that the robustness of our constructed network varied for different degradation modes: the degradation of the opinion leaders’ collaborative behavior had the lowest robustness; this was followed by the main knowledge dissemination behavior and the main knowledge contribution behavior; the degradation of random behavior had the highest robustness. Our method revealed the influence of the degradation of collaborative behavior of different types of nodes on the robustness of the network. This could be used to formulate the management strategy of the open-source design community, thus promoting the stable development of OSPs.

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García Navarro, Carmen. "JOY HARJO'S ETHICAL MODES OF BEHAVIOR TOWARD THE LAND." Revista de Estudios Norteamericanos, no. 26 (2022): 153–74. http://dx.doi.org/10.12795/ren.2022.i26.09.

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Joy Harjo’s poetry may be used to reflect on how various cultural traditions experience the concept of “We” with regards to other species and the environment, for which creative forms of responsibility should be articulated. Today, humans and non-humans alike face numerous and significant challenges and threats that are becoming increasingly apparent in the specific context of climate change and environmental degradation. Harjo’s work raises concerns about the impact that current global crises are having on the environment and our relationship to places, and consequently, our sense of belonging. This article discusses the relevance of some of Harjo’s poetry for increasing consciousness about the earth’s vulnerability and the need for environmental justice, which may be found in small but fundamental acts of caring

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Cheng, Jiang, Han, and Wang. "A Life Prediction Model of Flywheel Systems Using Stochastic Hybrid Automaton." Electronics 8, no. 11 (October 29, 2019): 1236. http://dx.doi.org/10.3390/electronics8111236.

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This paper proposes a practical life prediction model for Flywheel Systems (FSs) using the Stochastic Hybrid Automaton (SHA) method. The reliability of motors and the performance degradation of bearings are considered key causes of the failure of FSs. The unit flywheel SHA model is established for the failure mechanism, considering burst failure of motors and the accumulated performance degradation of bearings. This prediction model also describes the dynamic relation of lifetime with the configurations of FSs, work modes, and running environments. Monte Carlo simulation results demonstrate that the life distributions of FSs are quite different if the spacecrafts run in various orbits or with different configurations, or under changed work modes. The proposed method provides an engineering reference and guidance for the scheme design and in-orbit mission planning of FSs.

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Kudzin, Marcin, Renata Żyłła, Zdzisława Mrozińska, and Paweł Urbaniak. "31P NMR Investigations on Roundup Degradation by AOP Procedures." Water 11, no. 2 (February 15, 2019): 331. http://dx.doi.org/10.3390/w11020331.

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The reactions of (N-(PhosphonoMethyl)Glycine) PMG with H2O2 in homogenous systems were investigated using 31P NMR (Nuclear Magnetic Resonance). These reactions were carried out in two reaction modes: without UV radiation and under UV radiation. The reactions of PMG with H2O2 without UV radiation were carried out in two modes: the degradations of PMG (0.1 mmol) by means of 5–10 molar excess of hydrogen dioxide (PMG-H2O2 = 1:5 and 1:10) and the degradation of PMG (0.1 mmol) in homogenous Fenton reactions (PMG-H2O2-Fe2+ = 1:10:0.05 and 1:10:0.1). All reactions were carried out at ambient temperature, at pH 3.5, for 48 h. The reactions of PMG (in Roundup herbicide composition, 12 mmol) with H2O2 under UV radiation (254 nm) were carried out using 5 × molar excess of H2O2 (60 mmol), in the pH range of 2 ≤ pH ≤ 12, for 6 h. In this mode of PMG oxidation, the splitting of C-P was observed in the ratios dependent on the applied pH of the reaction mixture.

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Till, Andreas, Ronak Lakhani, Sarah F. Burnett, and Suresh Subramani. "Pexophagy: The Selective Degradation of Peroxisomes." International Journal of Cell Biology 2012 (2012): 1–18. http://dx.doi.org/10.1155/2012/512721.

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Peroxisomes are single-membrane-bounded organelles present in the majority of eukaryotic cells. Despite the existence of great diversity among different species, cell types, and under different environmental conditions, peroxisomes contain enzymes involved inβ-oxidation of fatty acids and the generation, as well as detoxification, of hydrogen peroxide. The exigency of all eukaryotic cells to quickly adapt to different environmental factors requires the ability to precisely and efficiently control peroxisome number and functionality. Peroxisome homeostasis is achieved by the counterbalance between organelle biogenesis and degradation. The selective degradation of superfluous or damaged peroxisomes is facilitated by several tightly regulated pathways. The most prominent peroxisome degradation system uses components of the general autophagy core machinery and is therefore referred to as “pexophagy.” In this paper we focus on recent developments in pexophagy and provide an overview of current knowledge and future challenges in the field. We compare different modes of pexophagy and mention shared and distinct features of pexophagy in yeast model systems, mammalian cells, and other organisms.

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Gasper, Paul, Nils Collath, Holger C. Hesse, Andreas Jossen, and Kandler Smith. "Machine-Learning Assisted Identification of Accurate Battery Lifetime Models with Uncertainty." Journal of The Electrochemical Society 169, no. 8 (August 1, 2022): 080518. http://dx.doi.org/10.1149/1945-7111/ac86a8.

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Reduced-order battery lifetime models, which consist of algebraic expressions for various aging modes, are widely utilized for extrapolating degradation trends from accelerated aging tests to real-world aging scenarios. Identifying models with high accuracy and low uncertainty is crucial for ensuring that model extrapolations are believable, however, it is difficult to compose expressions that accurately predict multivariate data trends; a review of cycling degradation models from literature reveals a wide variety of functional relationships. Here, a machine-learning assisted model identification method is utilized to fit degradation in a stand-out LFP-Gr aging data set, with uncertainty quantified by bootstrap resampling. The model identified in this work results in approximately half the mean absolute error of a human expert model. Models are validated by converting to a state-equation form and comparing predictions against cells aging under varying loads. Parameter uncertainty is carried forward into an energy storage system simulation to estimate the impact of aging model uncertainty on system lifetime. The new model identification method used here reduces life-prediction uncertainty by more than a factor of three (86% ± 5% relative capacity at 10 years for human-expert model, 88.5% ± 1.5% for machine-learning assisted model), empowering more confident estimates of energy storage system lifetime.

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Zhao, Zhiao, Yong Zhang, Guanjun Liu, and Jing Qiu. "Sample selection of prognostics validation test based on multi-stage Wiener process." Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability 233, no. 4 (November 2, 2018): 605–14. http://dx.doi.org/10.1177/1748006x18805835.

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Sample allocation and selection technology is of great significance in the test plan design of prognostics validation. Considering the existing researches, the importance of prognostics samples of different moments is not considered in the degradation process of a single failure. Normally, prognostics samples are generated under the same time interval mechanism. However, a prognostics system may have low prognostics accuracy because of the small quantity of failure degradation and measurement randomness in the early stage of a failure degradation process. Historical degradation data onto equipment failure modes are collected, and the degradation process model based on the multi-stage Wiener process is established. Based on the multi-stage Wiener process model, we choose four parameters to describe different degradation stages in a degradation process. According to four parameters, the sample selection weight of each degradation stage is calculated and the weight of each degradation stage is used to select prognostics samples. Taking a bearing wear fault of a helicopter transmission device as an example, its degradation process is established and sample selection weights are calculated. According to the sample selection weight of each degradation process, we accomplish the prognostics sample selection of the bearing wear fault. The results show that the prognostics sample selection method proposed in this article has good applicability.

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Wada, Yoshinori, and Takatomo Enoki. "Degradation Modes of InGaAs p-n Diodes Operated at Forward Biases." Japanese Journal of Applied Physics 37, Part 1, No. 10 (October 15, 1998): 5510–14. http://dx.doi.org/10.1143/jjap.37.5510.

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Wu, JiChun, Yu Sheng, QingBai Wu, and Zhi Wen. "Processes and modes of permafrost degradation on the Qinghai-Tibet Plateau." Science in China Series D: Earth Sciences 53, no. 1 (December 28, 2009): 150–58. http://dx.doi.org/10.1007/s11430-009-0198-5.

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Journal articles on the topic 'Degradation modes'

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