Littérature scientifique sur le sujet « Static stress change »
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Articles de revues sur le sujet "Static stress change"
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Hardebeck, Jeanne L. « The impact of static stress change, dynamic stress change, and the background stress on aftershock focal mechanisms ». Journal of Geophysical Research : Solid Earth 119, no 11 (novembre 2014) : 8239–66. http://dx.doi.org/10.1002/2014jb011533.
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Santos, Leandra, Yan Campo, Douglas da Silva, Thiago Burgo et Fernando Galembeck. « Rubber Surface Change and Static Charging under Periodic Stress ». Colloids and Interfaces 2, no 4 (6 novembre 2018) : 55. http://dx.doi.org/10.3390/colloids2040055.
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Rubber materials play an important role in robotics, due to their sensing and actuating abilities, that are exploited in soft smart materials endowed with shape-adaptive and electroadhesive properties. The application of an electric field produces non-linear deformation that has been extensively modelled, but is not understood at the molecular level. The symmetric effect (the production of an electric field due to rubber deformation) was recently discovered and explained as follows: rubber surface chemical composition and adsorptive properties change during rubber deformation, allowing the surface to exchange charge with the atmosphere. The present work describes the complex surface morphology and microchemistry of tubing made from vulcanized natural rubber, showing that it is rough and made from two domain types: stiffer elevations containing Br or Al (depending on the sample used) and O, that rise above an elastic base that is exempt of elements other than C and H. The surface area fraction occupied by the elastic base is higher in the strained rubber than when it is relaxed. Electrostatic potential on rubber surfaces was measured as a function of the stretching frequency, using Kelvin electrodes and showing frequency-dependent potential variation. This is explained considering charge exchange between the atmosphere and rubber surface, mediated by water vapor adsorbed in the stretched rubber and trapped when it relaxes.
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Tsaplev, V. M., R. S. Konovalov et S. I. Konovalov. « The Effect of Static Stress on the Anisotropy of Piezoceramics ». Materials 15, no 15 (26 juillet 2022) : 5186. http://dx.doi.org/10.3390/ma15155186.
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The influence of static compressional stress on the anisotropy of piezoelectric ceramics of BaTiO3 and PZT types is considered theoretically and experimentally. Static compression changes the domain structure of piezoceramics. These changes occur due to the reorientation of mostly 90° domain axes. As a result, all the parameters of the material change—elastic, piezoelectric, and dielectric. Some of them increase, and some, on the contrary, decrease. Changes occur in a nonlinear way, and higher-order parameters appear. The relationship between the total volume of the reoriented domains and the change in elastic moduli and piezomoduli is theoretically considered. The corresponding theoretical dependences are obtained. To confirm these theoretical dependences, experimental measurements were performed using the ultrasonic pulse-interference method at a frequency of 8 MHz. There is practically no oscillation movement of domain boundaries at this frequency, therefore, the change in the system of elastic and piezoelectric moduli is structural, not dynamic. The possibility of predicting changes in the structure of modules as a result of static compression is shown.
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Belmas, Ivan, Hanna Tantsura, Olena Bilous, Anhelina Shvachka et Yuliana Gupalo. « Investigation of a static rope with a cable break ». Strength of Materials and Theory of Structures, no 108 (30 mai 2022) : 349–59. http://dx.doi.org/10.32347/2410-2547.2022.108.349-359.
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Abstract. Establishing the influence of changes in the temporary properties of rubber on the stress state of the rubber traction body with a damaged cable. The method of research consists in the analytical solution of the model of the humorous traction body taking into account the rupture of the cable continuity and the change in the properties of the rubber. The dependences of the change of the stress state of the traction body of the humotross with the broken structure due to the rheology of the rubber shell are established. An algorithm for determining the stress state of a rubber traction body in case of its failure is formulated. It is shown that the loads on the ropes caused by the rupture of one of them lead to a local redistribution of forces almost only between two cables - damaged and adjacent; when damaged, non-extreme cable forces change in almost only three cables - damaged and two related. There are no extreme values of the internal load forces of the cables, which depend on the change of the shear modulus of the rubber material over time.
Construction of a method for determining the influence of impulses of individual cables of a cable rubber rope on its stress state.
Development and solution of the model of stress-strain state of the cable rubber rope with breaks in the continuity of the cables.
Methods of determining the stress state of a cable rope with a damaged cable.
The mechanism and nature of the influence of the impulses of the continuity of the cable of the cable rubber rope on its stress-strain state.
The developed method allows to take into account the influence of cable bursts on the stress state of the humorous cable rope of arbitrary design. Its application will allow to reasonably determine the minimum reserves of strength under the condition of safe use of the rubber rope, including in case of rupture of individual cables.
The mechanism of influence of change of properties of rubber on pressure is established by a condition of a traction body taking into account a rupture of continuity of a cable and change of properties of rubber. Taking into account the dependence of the stress-strain state of the rope with local violations of the cable base on changes in mechanical properties of rubber provides the ability to predict the stress state of the rope to improve safety and reliability of rubber traction with a long service life.
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Hardebeck, Jeanne L., et Ruth A. Harris. « Earthquakes in the Shadows : Why Aftershocks Occur at Surprising Locations ». Seismic Record 2, no 3 (1 juillet 2022) : 207–16. http://dx.doi.org/10.1785/0320220023.
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Abstract For decades there has been a debate about the relative effects of dynamic versus static stress triggering of aftershocks. According to the static Coulomb stress change hypothesis, aftershocks should not occur in stress shadows—regions where static Coulomb stress has been reduced. We show that static stress shadows substantially influence aftershock occurrence following three M ≥ 7 California mainshocks. Within the modeled static Coulomb stress shadows, the aftershock rate is an order of magnitude lower than in the modeled increase regions. However, the earthquake rate in the stress shadows does not decrease below the background rate, as predicted by Coulomb stress change models. Aftershocks in the stress shadows exhibit different spatial–temporal characteristics from aftershocks in the stress increase regions. The aftershock rate in the stress shadows decays as a power law with distance from the mainshock, consistent with a simple model of dynamic stress triggering. These aftershocks begin with a burst of activity during the first few days after the mainshock, also consistent with dynamic stress triggering. Our interpretation is that aftershock sequences are the combined result of static and dynamic stress triggering, with an estimated ∼34% of aftershocks due to dynamic triggering and ∼66% due to static triggering.
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Li, Xian-Fang, et L. Roy Xu. « T-Stresses Across Static Crack Kinking ». Journal of Applied Mechanics 74, no 2 (20 janvier 2006) : 181–90. http://dx.doi.org/10.1115/1.2188016.
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This paper is concerned with the T-stress change before and after crack kinking in two-dimensional elastic solids. By using asymptotic analysis and the Westergaard stress function method, approximate analytical formulas for calculating the T-stress as well as stress intensify factors of an infinitesimal kink are given. Contributions from the T-stress before crack kinking, to the T-stress and the stress intensity factors of the kinked crack, are clearly described. It is noted that since the sign of the T-stress of a kinked open crack might be different from that of a main crack, simply using the sign of the T-stress before crack kinking is not sufficient to determine crack growth stability as observed in recent experiments.
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Caskey, S. J., et S. G. Wesnousky. « Static stress changes and earthquake triggering during the 1954 Fairview Peak and Dixie Valley earthquakes, central Nevada ». Bulletin of the Seismological Society of America 87, no 3 (1 juin 1997) : 521–27. http://dx.doi.org/10.1785/bssa0870030521.
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Abstract The 16 December 1954 Dixie Valley (MS 6.8) earthquake followed the Fairview Peak (MS 7.2) earthquake by only 4 min and 20 sec. A three-dimensional model of the two dip-slip fault systems based on recent detailed field studies shows the ruptures were separated by a 6-km step in surface trace. A boundary-element approach shows that the static stress changes imposed by rupture of the Fairview Peak earthquake are in the correct sense to explain the northward propagation of faulting along four distinct faults that comprise the Fairview Peak earthquake and the subsequent triggering of the Dixie Valley earthquake. The location of rupture end points at sites where static stresses change sign is also used to suggest that static stress changes may play a role in controlling the extent of fault ruptures. We also observe that the largest coseismic surface displacements tend to correlate with those sections of the faults showing the largest positive stress change from preceding ruptures.
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Parsons, Tom, Yosihiko Ogata, Jiancang Zhuang et Eric L. Geist. « Evaluation of static stress change forecasting with prospective and blind tests ». Geophysical Journal International 188, no 3 (25 janvier 2012) : 1425–40. http://dx.doi.org/10.1111/j.1365-246x.2011.05343.x.
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Liu, Yu, Rui Jing et Peiyu Yan. « Effects of Mineral Admixtures on the Evolution of Static Yield Stress of Different Composite Pastes ». Processes 11, no 2 (17 février 2023) : 614. http://dx.doi.org/10.3390/pr11020614.
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The effects of different mineral admixtures on the evolution of static yield stress of common composite cementitious material paste and ultra-high-performance concrete (UHPC)-based paste were investigated. The results show that there are obvious differences in the role of mineral admixtures in the common paste and the UHPC-based paste. Adding mineral admixtures can change the initial static yield stress of the paste by affecting the particle size, particle shape and the charged particles. The addition of mineral admixtures with small particle size such as silica fume and ultrafine slag can increase the initial static yield stress of common paste but reduce that of UHPC-based paste. Adding mineral admixtures changes the evolution of static yield stress of the paste by affecting the particle spacing and the formation and growth rate of hydration products. In turn, the addition of ultrafine slag or silica fume increases the growth of the static yield stress of common paste. Adding slag, fly ash or fly ash microbeads successively reduces the static yield stress of common paste at the later stage. Affected by the content of PCE, the static yield stress of UHPC-based paste containing fly ash microbeads, slag, ultrafine slag and fly ash increases sequentially compared with the blank group at the later stage. The effect of silica fume with different dosages on the evolution of static yield stress of UHPC-based paste is significantly different.
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Jiménez-Donaire, María del Pilar, Juan Vicente Giráldez et Tom Vanwalleghem. « Impact of Climate Change on Agricultural Droughts in Spain ». Water 12, no 11 (17 novembre 2020) : 3214. http://dx.doi.org/10.3390/w12113214.
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Drought is an important natural hazard that is expected to increase in frequency and intensity as a consequence of climate change. This study aimed to evaluate the impact of future changes in the temperature and precipitation regime of Spain on agricultural droughts, using novel static and dynamic drought indices. Statistically downscaled climate change scenarios from the model HadGEM2-CC, under the scenario representative concentration pathway 8.5 (RCP8.5), were used at a total of 374 sites for the period 2006 to 2100. The evolution of static and dynamic drought stress indices over time show clearly how drought frequency, duration and intensity increase over time. Values of static and dynamic drought indices increase over time, with more frequent occurrences of maximum index values equal to 1, especially towards the end of the century (2071–2100). Spatially, the increase occurs over almost the entire area, except in the more humid northern Spain, and in areas that are already dry at present, which are located in southeast Spain and in the Ebro valley. This study confirms the potential of static and dynamic indices for monitoring and prediction of drought stress.
Thèses sur le sujet "Static stress change"
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BONALI, FABIO LUCA. « Earthquake induced static stress change in promoting eruptions ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/50170.
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The aim of this PhD work is to study how earthquakes could favour new eruptions, focusing the attention on earthquake-induced static effects in three different case sites. As a first case site, I studied how earthquake-induced crustal dilatation could trigger new eruptions at mud volcanoes in Azerbaijan. Particular attention was then devoted to contribute to the understanding of how earthquake-induced magma pathway unclamping could favour new volcanic activity along the Alaska-Aleutian and Chilean volcanic arcs, where 9 seismic events with Mw ≥ 8 occurred in the last century.
Regarding mud volcanoes, I studied the effects of two earthquakes of Mw 6.18 and 6.08 occurred in the Caspian Sea on November 25, 2000 close to Baku city, Azerbaijan. A total of 33 eruptions occurred at 24 mud volcanoes within a maximum distance of 108 km from the epicentres in the five years following the earthquakes. Results show that crustal dilatation might have triggered only 7 eruptions at a maximum distance of about 60 km from the epicentres and within 3 years. Dynamic rather than static strain is thus likely to have been the dominating “promoting” factor because it affected all the studied unrested volcanoes and its magnitude was much larger.
Regarding magmatic volcanoes, the entire dataset includes a total of 51 eruptions following 9 large earthquakes (Mw ≥ 8); 33 represent first new eruptions occurred at each single volcano. Comparison of the eruption rate before and after each earthquake suggests that 26 out of the 33 first new eruptions have a positive relation with the studied earthquakes; 13 out of 26 represent awakening events, which are first new eruptions occurred at volcanoes with not-continuous eruptive activity that had no eruptions in the five years before the earthquake. I followed a novel approach that resolves the earthquake-induced static stress change normal to the magma pathway of each volcano instead of considering the general crustal volume. I also considered other parameters that may contribute to control eruptions, such as magma composition and viscosity, magma chamber depth and local tectonic settings.
The sensitivity analysis performed for the 2010 Chile earthquake shows that the N-S- and NE-SW-striking magma pathways suffered a larger unclamping in comparison with those striking
NW-SE and E-W. Magma pathway parallel or subparallel to the strike of modelled faults suffered the highest unclamping, and this was also evident in the Alaska-Aleutian arc. Magma pathway geometry controls the magnitude of the static stress change induced by large earthquakes, with differences of up to 8 times among magma-feeding planes of different orientation at the same volcano. This range of diverse values is larger for the volcanoes closer to the epicentre. The possible error in the estimate of magma chamber depth has a minimum effect on the results since the sensitivity analysis shows that the range of stress changes with depth is about 1.5 orders of magnitude smaller than the range linked to variations in the magma pathway strike.
Result suggest that unclamping effect promoted eruptions that occurred at not-continuously erupting volcanoes (Type B) in a range of 157-543 km, while awakening under unclamping occurred in a range of 157-353 km. Regarding the time-gap, unclamping promoted eruptions at Type B volcanoes and awakening in a time window of 2 days-3 years. In the studied cases, it was also noted that unclamping enhanced eruptions preferentially at volcanoes with a deep magma chamber (> 5 km).
Regarding the role of magma pathway geometry, results suggest that 4 awakening events occurred along magma pathways parallel or subparallel to the σHmax, and they are always under unclamping. Eleven awakening events occurred along magma pathways that have an angle from 40° to 90° respect to the σHmax, thus unclamping favoured 8 of these events.
Finally, based on the results from this work, I suggest that earthquake-induced stress change can favour magma rise by imparting stress field modifications of the deviatoric stress acting on magma pathway in a percentage up to 5-10 %, increasing the efficiency of magma rise and consequent dyke intrusion also where the tectonic regime doesn’t favour magma rise (e.g. in the older and thicker crust in Chile under contractional tectonics).
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Bagge, Meike [Verfasser]. « Three-dimensional numerical modelling of static and transient Coulomb stress changes on intra-continental dip-slip faults / Meike Bagge ». Hannover : Technische Informationsbibliothek (TIB), 2017. http://d-nb.info/1136093176/34.
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Kharel, Usha. « Analysis of Stream Runoff Trends in the Blue Ridge and Piedmont of Southeastern United States ». Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/geosciences_theses/15.
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The purpose of the study was to examine the temporal trends of three monthly variables: stream runoff, rainfall and air temperature and to find out if any correlation exists between rainfall and stream runoff in the Blue Ridge and Piedmont provinces of the southeast United States. Trend significance was determined using the non-parametric Mann-Kendall test on a monthly and annual basis. GIS analysis was used to find and integrate the urban and non-urban stream gauging, rainfall and temperature stations in the study area. The Mann-Kendall test showed a statistically insignificant temporal trend for all three variables. The correlation of 0.4 was observed for runoff and rainfall, which showed that these two parameters are moderately correlated.
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Zamora, Nadine Valerie Perez. « The impact of stressful life events and exposure to community violence on delinquency in Hispanic pre-adolescents ». CSUSB ScholarWorks, 2003. https://scholarworks.lib.csusb.edu/etd-project/2422.
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The purpose of the current study was to examine delinquent pre-adolecents. It was hypothesized that both predictor variable [exposure to community violence (number of events; preception of events) and stressful life events (number of events)] would impact delinquent behavior (violent thoughts, violent behaviors, and promiscuity).
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Díez, Mikel. « Studies of the Mechanics and Structure of Shallow Magmatic Plumbing Systems ». Scholar Commons, 2008. https://scholarcommons.usf.edu/etd/214.
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Volcanic activity, and the resultant deposits and structures at the Earth's surface, are the outcome of the inner workings of underground magmatic plumbing systems. These systems, essentially, consist of magma reservoirs which supply magma to the surface through volcanic conduits feeding volcanic eruptions. The mechanics and structure of plumbing systems remain largely unknown due to the obvious challenges involved in inferring volcanic processes occurring underground from observations at the surface. Nevertheless, volcanologists are beginning to gain a deeper understanding of the workings and architecture of magmatic plumbing systems from geophysical observations on active volcanoes, as well as from geological studies of the erosional remnants of ancient volcanic systems.
In this work, I explore the relationship between the structure and mechanics of shallow plumbing systems and the volcanic eruptions these systems produce. I attempt to contribute to the understanding of this complex relationship by linking geological and geophysical observations of an eroded basaltic subvolcanic system, and the eruptive and tectonic activity of an active volcano, with mathematical models of magma ascent and stress transfer.
The remarkable exposures of the Carmel outcrop intrusions, near the San Rafael swell, southeast Utah, U. S. A., allow detailed geological and geophysical observations of the roots of volcanic conduits that emerge from a subhorizontal magma feeder reservoir. These observations reveal a new mechanism for magma ascent and eruption triggering through gravitational instabilities created from an underlying feeding sill, and shed light on the mechanics of sill emplacement. Geophysical and geological observations of the 1999 and xii 1992 eruptions of the Cerro Negro volcano, Nicaragua, are used to explore the coupling between changes in the stress field and the triggering of volcanic eruptions, and magma ascent through the shallow crust. Modeling results of stress transfer and conduit flow highlight the importance of the surrounding stress field and geometry of the volcanic conduits that comprise shallow plumbing systems.
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Tai, I.-ming, et 戴一明. « Changes of static stress and seismicity rate following large earthquakes of the Taiwan area ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/79421324899119198449.
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碩士國立中央大學
地球物理研究所
99
Taiwan is located on the boundary between the Eurasia Plate and the Philippines Sea Plate, where large earthquakes occur frequently and can induce lots of disasters and casualties. Thus, it is important to understand factors that would influence the temporal and spatial evaluations of seismicity in Taiwan, and this analysis will provide critical view for studies of earthquake hazard. Earthquake forecast has yet developed completely, but some preliminarily characters can be studied by the relationship between Coulomb stress changes and rates of earthquake occurrence. The positive correlation between increase of static Coulomb stress and high occurrence of aftershocks based on many researches has thus provided evidence that stress increase promotes seismicity. In this study, we chose three large earthquakes in Taiwan, including the 1998 Ruey-Li earthquake (Mw5.8), the 2003 Chen-Kung earthquake (Mw6.8) and the 2010 Jia-Shian earthquake (Mw6.0) to study the relationship between static Coulomb stress changes and seismicity rate changes. We estimated Coulomb stress changes on a optimal-oriented faults implied by regional tectonic stress fields. Results show that most of aftershocks are located in the area where Coulomb stress increases. Accordingly, about 61%, 66% and 35% of aftershocks located in the area of positive Coulomb stress changes for the earthquake sequences of Ruey-Li, Chen-Kung and Jia-Shian earthquake, respectively. In addition, we observed that the seismicity rate is higher after the occurrence of three main shocks than before. For the Chen-Kung earthquake, increased seismicity rates in area of positive stress changes decayed to background level five years after the main shock, and the trend of decay follows the Omori’s law.
Livres sur le sujet "Static stress change"
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C, McKenry Patrick, et Price Sharon J, dir. Families & change : Coping with stressful events and transitions. 2e éd. Thousand Oaks, Calif : Sage Publications, 2000.
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H, Elder Glen, dir. Families in troubled times : Adapting to change in rural America. New York : A. de Gruyter, 1994.
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You can eliminate stress from the I.R.S. : Your chance of being audited ? : at least once or twice in your lifetime. Lancaster, Pa : Starburst Publishers, 1992.
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Gerald, Lewis, Blunt Grace L, Durso Carmen L et Massachusetts Continuing Legal Education, Inc. (1982- ), dir. Proving or protecting against "intangible harm" : A new(er) understanding of psychological damage. [Boston, Mass.] : MCLE, 2004.
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Krivoyekov, Syergyey, et Roman Ayzman. Psychophysiology. ru : INFRA-M Academic Publishing LLC., 2015. http://dx.doi.org/10.12737/10884.
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Psychophysiology — the science studying interrelation of mentality of the person and physiological processes. Fundamental knowledge of work of a brain, first of all, of nervous regulation of functions of an organism, the general and specific features of the highest falls within the scope of its interests
nervous activity, the defining character and behavior of the person,
psychophysiological mechanisms of regulation of functional states.
In the book neurophysiological bases of coding and information processing in nervous system, neural mechanisms of feelings, perceptions, memories, training, motivations and emotions, thinking and the speech, attention, consciousness, behavior, mental activity are stated. Separate
the section is devoted to physiological bases of mental changes at various functional, extreme and pathophysiological states (a stress, post-stressful frustration, addiktivny states, depressions, etc.) and to ways of their correction. Authors tried to pay special attention to disclosure of specifics of psychophysiology of the person,
to difference of physiological mechanisms of regulation of mental functions of the person in comparison with model researches on animals.
For simplification of work on discipline and the best digestion of material
the textbook is supplied with the glossary.
For students, undergraduates, graduate students and teachers of psychological and medical faculties of higher education institutions.
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This changes everything : Occupy Wall Street and the 99% movement. San Francisco : Berrett-Koehler Publishers, 2011.
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Gunn, Betty Reedy, dir. Short Changed : Memoir of an American Combat Veteran. Atlanta, Georgia, USA : Tree Hugger Book Publishing, 2011.
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Occupying Wall Street : The inside story of an action that changed America. Chicago, IL : Haymarket Books, 2012.
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Leslie, David W. Wise moves in hard times : Creating and managing resilient colleges and universities. San Francisco : Jossey-Bass Publishers, 1996.
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Collision course : Ronald Reagan, the air traffic controllers, and the strike that changed America. New York : Oxford University Press, 2011.
Trouver le texte intégralChapitres de livres sur le sujet "Static stress change"
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Kim, Sung Soon, Jun Hyun Bae, Woo Hyuck Do, Kyun Ho Lee, Young Tae Kim, Young Kwan Park, Jeong Taek Kong et Hong Lim Lee. « Thermal Stress Model for Phase Change Random Access Memory ». Dans Solid State Phenomena, 37–40. Stafa : Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/3-908451-31-0.37.
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Loi, Doan Huy, S. H. S. Jayakody et Kyoji Sassa. « Teaching Tool “Undrained Dynamic Loading Ring Shear Testing with Video” ». Dans Progress in Landslide Research and Technology, Volume 1 Issue 2, 2022, 325–59. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-18471-0_25.
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AbstractUndrained dynamic-loading ring-shear apparatus (UDRA) is most appropriate to study landslide dynamics by simulating the entire process from the initial stage of stress before landslide occurrence and stress changes due to static, dynamic loading or pore pressure changes or other types of stress loading to the formation of a sliding surface and the steady-state shear resistance. This paper describes the mechanical structure of the apparatus of UDRA and provides a manual for readers to begin using the UDRA. Specific steps for testing procedures with video tutorials and data analysis are also provided in this paper. The paper concludes with a manual from start to finish for common ring shear tests: undrained monotonic shear stress control test, undrained cyclic loading test, undrained seismic loading test, and pore pressure control test.
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Rhoades, D. A., E. E. Papadimitriou, V. G. Karakostas, R. Console et M. Murru. « Correlation of Static Stress Changes and Earthquake Occurrence in the North Aegean Region ». Dans Seismogenesis and Earthquake Forecasting : The Frank Evison Volume II, 195–212. Basel : Springer Basel, 2010. http://dx.doi.org/10.1007/978-3-0346-0500-7_13.
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Magiri, Royford, Kaampwe Muzandu, George Gitau, Kennedy Choongo et Paul Iji. « Impact of Climate Change on Animal Health, Emerging and Re-emerging Diseases in Africa ». Dans African Handbook of Climate Change Adaptation, 1835–51. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_19.
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AbstractThe threat of climate change and global warming is gaining worldwide recognition. The African continent, because of its size, diversity, and its new status as a “hub” of livestock production, need to gear up to mitigate the possible impacts of climate change on animal health. The aim of this review article is to summarize the current state of knowledge regarding the influence of climate and climate change on the health of food-producing animals. Depending on its intensity and duration, heat stress may directly affect livestock health by causing metabolic disruptions, oxidative stress, and immune suppression, causing increased disease susceptibility, and death. Animal health could also be affected by emergence and re-emergence of vector- and non-vector-borne pathogens that are highly dependent on climatic conditions. The response to these challenges requires community participation in the adaptation of animal production systems to new environments and strengthening the efficiency of veterinary services delivery combined with well-coordinated public health services, since many emerging human diseases are zoonotic.
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Yamano, Takashi. « Diffusion of Submergence-Tolerant Rice in South Asia ». Dans Emerging-Economy State and International Policy Studies, 49–62. Singapore : Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5542-6_4.
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AbstractClimate change is expected to increase the incidence and magnitudes of extreme weather events. To help farmers mitigate the expected impacts of extreme weather events, abiotic stress-tolerant crop varieties have been developed. The diffusions of the stress-tolerant crop varieties, however, have been limited. This chapter reviews recent studies on the adoption and impacts of the submergence-tolerant rice varieties in South Asia. Studies have identified significant benefits of those rice varieties in South Asia using various survey and analytical methods. However, farmers have problems identifying submergence-tolerant rice varieties in informal seed markets. Using DNA fingerprinting, a study found that many farmers in Bangladesh could not identify varietal names correctly. Effective public interventions are needed to help farmers in flood-prone areas adopt submergence-tolerant rice varieties.
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Thierfelder, Christian, et Peter Steward. « Increasing adaptation to climate stress by applying conservation agriculture in Southern Africa. » Dans Conservation agriculture in Africa : climate smart agricultural development, 270–83. Wallingford : CABI, 2022. http://dx.doi.org/10.1079/9781789245745.0016.
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Abstract Climate change and soil fertility decline are threatening food security in southern Africa and efforts have been made to adapt current cropping systems to the needs of smallholder farmers. Conservation Agriculture (CA) based on minimum soil disturbance, crop residue retention and crop diversification has been proposed as a strategy to address the challenges smallholder farmers face. Here we analyse the potential contributions of CA towards adaptation to the effects of climate change by summarizing data on infiltration, soil moisture dynamics and crop productivity under heat and drought stress. The data were taken in the main from CIMMYT's on-farm and on-station trial network. Data show that CA systems maintain 0.7-7.9 times higher water infiltration than the conventional tilled system depending on soil type, which increases soil moisture during the cropping season by 11%-31% between CA treatments and the conventional control treatment. This leads to greater adaptive capacity of CA systems during in-season dry spells and under heat stress. A supporting regional maize productivity assessment, analysing the results of numerous on-farm and on-station experiments, showed that CA systems will outperform conventional tillage practices (CP), especially on light-textured soils, under heat and drought stress. With higher rainfall and low heat stress, this relation was more positive towards CP and on clay soil there was no benefit of practising CA when rainfall was high. The long dry season and limited biomass production of CA systems in southern Africa require complementary good agricultural practices to increase other soil quality parameters (e.g. increased soil carbon) to maintain higher productivity and sustainability over time. This can be addressed by combinations of improved stress-tolerant seed, targeted fertilization, inclusion of tree-based components or green manure cover crops in the farming system, scale-appropriate mechanization and improved weed control strategies.
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Chen, Peng, Jinyou Lu, Zhongwu Jin, Yinjun Zhou, Rouxin Tang, Zhaoxi Liu et Qiuba Han. « Spatiotemporal Evolution Characteristics and Influencing Factors of Incoming Water and Sediment in Three Gorges Reservoir ». Dans Lecture Notes in Civil Engineering, 1535–52. Singapore : Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6138-0_136.
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AbstractBased on the hydrological and sediment observation data of the main stream and main stream of the upper Yangtze River from 1956 to 2018, using M-K test, Wavelet analysis, Approximate entropy and Lyapunov exponent, this paper analyzes the spatiotemporal evolution characteristics from the perspectives of catastrophe, periodicity, complexity and chaos of incoming water and sediment in The TGR (TGR), defines the connotation of “new water and sediment conditions” in the TGR, and discusses the main influencing factors of spatiotemporal variation of incoming water and sediment in the TGR. The results show that: (1) Except Pingshan station of Jinsha River, Fushun station of Tuojiang River and Wulong station of Wujiang River, the runoff of other main and tributaries and TGR in the upper Yangtze River has no significant change, but the sediment discharge has obvious mutation, and the runoff and sediment have periodic changes in different degrees; (2) The complexity of annual runoff and sediment transport in the TGR increases gradually, and the complexity of sediment transport is greater than that of runoff. Both annual runoff and sediment transport are chaotic, and the complexity of runoff and sediment transport sequence increases gradually from the upper reaches to the lower reaches; (3) The connotation of “new water and sediment condition” shows that there is no obvious mutation in runoff and sediment transport in time scale, the main cycle of water and sediment change is basically the same, and the complexity and chaos of sediment transport in space scale are significantly greater than runoff, and the change degree of sediment transport is more significant than runoff; (4) From 1991 to 2002, climate change (rainfall) was an important factor affecting the sediment discharge in the upper Yangtze River. From 2003 to 2018, the impact of climate change was relatively insignificant, and human activities became the most important factor.
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Kumar, S. R., G. Mohanapriya et R. Sathishkumar. « Abiotic Stress-Induced Redox Changes and Programmed Cell Death in Plants—A Path to Survival or Death ? » Dans Redox State as a Central Regulator of Plant-Cell Stress Responses, 233–52. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-44081-1_11.
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Johnson, Richard K., Daniel Hering, Mike T. Furse et Piet F. M. Verdonschot. « Indicators of ecological change : comparison of the early response of four organism groups to stress gradients ». Dans The Ecological Status of European Rivers : Evaluation and Intercalibration of Assessment Methods, 139–52. Dordrecht : Springer Netherlands, 2006. http://dx.doi.org/10.1007/978-1-4020-5493-8_10.
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Iyiola-Tunji, Adetunji Oroye, James Ijampy Adamu, Paul Apagu John et Idris Muniru. « Dual Pathway Model of Responses Between Climate Change and Livestock Production ». Dans African Handbook of Climate Change Adaptation, 523–62. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_230.
Texte intégralRésumé :
AbstractThis chapter was aimed at evaluating the responses of livestock to fluctuations in climate and the debilitating effect of livestock production on the environment. Survey of livestock stakeholders (farmers, researchers, marketers, and traders) was carried out in Sahel, Sudan, Northern Guinea Savannah, Southern Guinea Savannah, and Derived Savannah zones of Nigeria. In total, 362 respondents were interviewed between April and June 2020. The distribution of the respondents was 22 in Sahel, 57 in Sudan, 61 in Northern Guinea Savannah, 80 in Southern Guinea Savannah, and 106 in Derived Savannah. The respondents were purposively interviewed based on their engagement in livestock production, research or trading activities. Thirty-eight years’ climate data from 1982 to 2019 were obtained from Nigerian Metrological Agency, Abuja. Ilela, Kiyawa, and Sabon Gari were chosen to represent Sahel, Sudan, and Northern Guinea Savannah zone of Nigeria, respectively. The data contained precipitation, relative humidity, and minimum and maximum temperature. The temperature humidity index (THI) was calculated using the formula: THI = 0.8*T + RH*(T-14.4) + 46.4, where T = ambient or dry-bulb temperature in °C and RH=relative humidity expressed as a proportion. Three Machine Learning model were built to predict the monthly minimum temperature, maximum temperature, and relative humidity respectively based on information from the previous 11 months. The methodology adopted is to treat each prediction task as a supervised learning problem. This involves transforming the time series data into a feature-target dataset using autoregressive (AR) technique. The major component of the activities of livestock that was known to cause injury to the environment as depicted in this chapter was the production of greenhouse gases. From the respondents in this chapter, some adaptive measures were stated as having controlling and mitigating effect at reducing the effect of activities of livestock on the climate and the environment. The environment and climate on the other side of the dual pathway is also known to induce stress on livestock. The concept of crop-livestock integration system is advocated in this chapter as beneficial to livestock and environment in the short and long run. Based on the predictive model developed for temperature and relative humidity in a sample location (Ilela) using Machine Learning in this chapter, there is need for development of a web or standalone application that will be useable by Nigerian farmers, meteorological agencies, and extension organizations as climate fluctuation early warning system. Development of this predictive model needs to be expanded and made functional.
Actes de conférences sur le sujet "Static stress change"
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Kang, Kyungho, Marit Nilsen-Hamilton et Pranav Shrotriya. « Novel Differential Surface Stress Sensor for Detection of DNA Hybridization ». Dans ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206838.
Texte intégralRésumé :
A fiber optic coupled interferometric system designed to measure differential surface stress induced by DNA hybridization of (dA)30 single-stranded DNA (ssDNA) with complementary (dT)30 ssDNA in aqueous environment. The sensing system is amenable to miniaturize into a single MEMS-chip and performed direct detection of nanomechanical response of conformational change and the corresponding charge transduction during molecular adsorption. The static deflection of functionalized sensing cantilever respect to reference cantilever which passivated from additional target molecules converts into a surface stress change for quantitative analysis. The measured surface stress changes were turned to be 40 to 110 mN/m for the concentrations of 0.1 to 1.0 μM of target molecules associated with the dissociation constant (Kd) of 168 nM. X-ray photoelectron spectroscopy (XPS) analysis and noncomplementary experiments were also considered for the validity and reliability of the system.
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Hashimoto, Shigehiro, Hiroki Yonezawa et Ryuya Ono. « Cell Activity Change After Division Under Wall Shear Stress Field ». Dans ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-69689.
Texte intégralRésumé :
Abstract Does cell orientation depend on the cell type in the shear stress field? Does that tendency change after the division? In this study, the behavior of each cell after division was tracked by time-lapse microscopic images through 24 hours of culture under a shear stress field. A constant shear stress field was applied to the cells in the Couette flow between the parallel walls: the lower static culture disc and the upper rotating disc. For comparison, four types of cells were used: C2C12 (mouse myoblast), HUVEC (human umbilical vein endothelial cells), 3T3-L1 (mouse adipose progenitor cells), and L929 (mouse fibroblast). The result is as follows. In the wall shear stress field of 1 Pa, HUVEC is oriented parallel to the flow, regardless of the division. In other cell types (C2C12, 3T3-L1, and L929) after division, the deformed cell tends to tilt to the direction parallel to the flow. The experimental results are expected to be applied to engineered tissue technologies.
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Tao, R. « Static and Dynamic Structures of Polarizable Fluids ». Dans ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0482.
Texte intégralRésumé :
Abstract In a strong electric field, polarizable fluids have a structural transition at a critical shear stress. When there is no flow, polarizable fluids form a body-centered tetragonal lattice which consists of closely packed chains. When the shear stress is increased from zero up to a critical value, the flow (in x-direction) has a flowing-chain (FC) structure, consisting of tilted or broken chains along the field (z-direction). At the critical shear stress, the FC structure gives way to a flowing-hexagonal-layered (FHL) structure, consisting of several two-dimensional layers which are parallel to the x-z plane. Within one layer, particles form strings in the flow direction. The effective viscosity drops dramatically at the structural change. As the shear stress reduces, the FHL structure persists even under a stress-free state if the thermal fluctuation is very weak.
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Yoo, JinHyeong, James B. Restorff et Marilyn Wun-Fogle. « Non-Contact Tension Sensing Using Fe-Ga Alloy Strip ». Dans ASME 2015 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/smasis2015-8909.
Texte intégralRésumé :
This paper describes a proof-of-concept non-contact strain sensor, using a magnetostrictive Fe-Ga alloy (Galfenol). Magnetostrictive materials demonstrate dimensional changes in response to a magnetic field. In contrast with typical piezoceramic materials, Galfenol is the most ductile of the current transduction materials and appears to have an excellent ability to withstand mechanical shock and tension. Galfenol also exhibits the inverse (Villari) effect: both the magnetization and permeability change in response to an applied stress. Galfenol has low hysteresis loses, less than ∼10% of its transduction potential over a range of −20 to +80 °C. The magnetization’s response to stress depends strongly on both magnetic field bias and alloy composition. Galfenol’s Villari effect can be used in various sensor configurations together with either a giant magnetoresistance (GMR) sensor, Hall Effect sensor or pickup coil to sense the magnetization / permeability changes in Galfenol when stressed. The sensor described in this paper utilizes the permeability change, which is not time dependent and can measure static loads. The design reported here targets low force, low frequency applications, such as inclination measurements and stress monitoring. The sensor was able to measure both static and dynamic stress. The static sensitivity was +3.64 Oe/kN for the Hall sensor close to the bias magnet and −1.49 Oe/kN for the Hall sensor at the other end of the Galfenol strip. We conclude that a Galfenol strain sensor is a viable candidate for bolt stress monitoring in critical applications.
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Horton, J. Wright, Mark W. Carter, Martin C. Chapman, Qimin Wu, Anne C. Witt et Anjana K. Shah. « THE 2011 MINERAL, VIRGINIA, EARTHQUAKE TRIGGERED SHALLOW AFTERSHOCKS ON FAVORABLY ORIENTED STRUCTURES IN AREAS OF POSITIVE STATIC COULOMB STRESS CHANGE ». Dans 66th Annual GSA Southeastern Section Meeting - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017se-289995.
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Nakatsuchi, Hiroki, Naoyuki Watanabe, Yukio Nakatsuchi, Shigeru Tadano, Tetsuji Moriizumi, Shinichiro Mori et Masahiro Endo. « Biomechanical Role of Trabecula Networks in the Human Proximal Femur Under Static Loading ». Dans ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-60100.
Texte intégralRésumé :
Finite element models of human femur were constructed from micro structural data measured by a three-dimensional cone beam CT with the resolution of a 0.35mm cube as a voxel size. The results of static analysis on the assumption with one-legged support standing revealed that the tensile stress in the lateral cortex of the femoral neck and the compressive stress in the medical cortex remarkably increased after removing the trabecula networks. The change of stress distribution means that the trabecula networks would make a contribution to dissipating the concentration of tensile and compressive stress in the region of femoral neck. Therefore, the stress concentration even in static condition will increase the fracture risk of femoral neck as osteoporosis advances.
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Afshari, Mana, et Nader Jalili. « A Sensitivity Study on Static and Dynamic Detection Modes of Adsorption-Induced Surface Stress in Microcantilever Biosensors ». Dans ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-35424.
Texte intégralRésumé :
Microcantilever biosensors may be utilized as a platform for the adsorption induced surface stress measurements. This can be done by measuring either the static deflection of the microcantilever after the adsorption or the adsorption induced shift in its resonance frequency. This paper presents a new method of formulating the adsorption induced surface stress as a function of the static deflection of the microcantilever. Most of the previous works in this area are based on the Stoney’s simple equation. In the proposed method, the molecular interactions of the adsorbed biological species are modeled based on the Lennard-Jones attraction/repulsion potential. As a result, the sensitivity of the static detection mode (based on the proposed method) is compared to that of the dynamic mode. It is shown that the dynamic mode of biosensing is much more sensitive to the change in the properties of the adsorbed biological species, when compared to conventional static mode detection mechanism.
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Huang, Y., et H. Gao. « Suddenly Arrested Intersonic Shear Crack ». Dans ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/amd-25402.
Texte intégralRésumé :
Abstract We study a mode II crack suddenly stopping after propagating intersonically for a short time. The solution is obtained by superposing the fundamental solution and the auxiliary problem of a static crack emitting dynamic dislocations such that the relative crack face displacement in the fundamental solution is negated ahead of where the crack tip has stopped. We find that, after the crack stops moving, the stress intensity factor rapidly rises to a finite value and then starts to change gradually toward the equilibrium value for a static crack. A most interesting feature is that the static value of stress intensity is reached neither instantaneously like a suddenly stopping subsonic crack nor asymptotically like a suddenly stopping edge dislocation. Rather, the dynamic stress intensity factor changes continuously as the shear and Rayleigh waves catch up with the stopped crack tip from behind, approaches negative infinity when the Rayleigh wave arrives, and then suddenly assumes the equilibrium static value when all the waves have passed by. This study is an important step toward the study of intersonic crack propagation with arbitrary, non-uniform velocities.
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Isobe, Koki, Ken Suzuki et Hideo Miura. « Mechanical Stress Monitoring Sensor for 3-D Module During Manufacturing and Operation ». Dans ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-70323.
Texte intégralRésumé :
In three-dimensional packaging module which have been used in electronic equipment, the size of partial interconnections and total structure have been continuously miniaturized for improving the performance of the products. Due to the fluctuation of the mechanical properties of the component materials and the drop impact towards the fragile modules during manufacturing and operation, the final residual stress varies easily in a chip of the 3-D structure. Both the static and dynamic changes of the stress distribution induce the variation of the performance of electronic devices and the degradation of their long-term reliability. It is, therefore, important to control and optimize the residual stress quantitatively. In this study, a stress sensor which can monitor the change of the local residual stress in 3-D module was developed by applying the piezoresistance effect of single-crystalline silicon. The sensor was embedded in a silicon chip, and it can measure the periodic stress in a silicon chip assembled by area-arrayed bump structure. The impact stress during the manufacturing process was successfully monitored by using this sensor. It was also confirmed that the effective amplitude of the impact stress varies drastically depending on the mechanical properties of the stacked thin films.
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Tsui, Y. C., T. W. Clyne et R. C. Reed. « On the Change in Stress State Associated with Bond Coat Oxidation during Heat Treatment of a Thermal Barrier Coating System ». Dans ITSC 1997, sous la direction de C. C. Berndt. ASM International, 1997. http://dx.doi.org/10.31399/asm.cp.itsc1997p0267.
Texte intégralRésumé :
Abstract Thermal barrier coating systems have been heat treated in order to study the oxidation kinetics of the bond coat. All the surfaces of Ni superalloy substrates were sprayed with ~100 μm of a NiCrAlY bond coat, with or without ~250 μm of a ZrO2 top coat. Thermogravimetric analysis (TGA) was used to monitor continuously the mass change as a result of oxidation of the bond coat during heating at 1000°C for 100 hours in flowing air. In addition, some specimens were heated to 1000°C in static air, cooled to room temperature, weighed and re-heated cyclically. The total exposure time was 1000 hours. Rates of weight gain were found to be higher for the cycled specimens, despite the absence of air flow. This is attributed to damage to the oxide film, which was predominantly α-Al2O3, as a consequence of differential thermal contraction stresses. The changing residual stress state during heat treatment was predicted using a previously-developed numerical model. A thin (1 mm) substrate with ~100 μm bond coat and ~250 μm ZrO2 top coat was used in these simulations, which incorporated creep of the bond coat and the lateral strain associated with oxidation. It is concluded from these computations that, while high stresses develop in the oxide layer, the associated driving forces for interfacial debonding remain relatively low, as do specimen curvature changes. It seems likely that coating spallation after extensive oxide layer formation arises because the interface is strongly embrittled as the layer thickens.
Rapports d'organisations sur le sujet "Static stress change"
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Morgan, Mary E. Permanent Change of Station and Stress. Fort Belvoir, VA : Defense Technical Information Center, avril 1991. http://dx.doi.org/10.21236/ada236511.
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Cooper, Christopher, Jacob McDonald et Eric Starkey. Wadeable stream habitat monitoring at Congaree National Park : 2018 baseline report. National Park Service, juin 2021. http://dx.doi.org/10.36967/nrr-2286621.
Texte intégralRésumé :
The Southeast Coast Network (SECN) Wadeable Stream Habitat Monitoring Protocol collects data to give park resource managers insight into the status of and trends in stream and near-channel habitat conditions (McDonald et al. 2018a). Wadeable stream monitoring is currently implemented at the five SECN inland parks with wadeable streams. These parks include Horseshoe Bend National Military Park (HOBE), Kennesaw Mountain National Battlefield Park (KEMO), Ocmulgee Mounds National Historical Park (OCMU), Chattahoochee River National Recreation Area (CHAT), and Congaree National Park (CONG). Streams at Congaree National Park chosen for monitoring were specifically targeted for management interest (e.g., upstream development and land use change, visitor use of streams as canoe trails, and potential social walking trail erosion) or to provide a context for similar-sized stream(s) within the park or network (McDonald and Starkey 2018a). The objectives of the SECN wadeable stream habitat monitoring protocol are to: Determine status of upstream watershed characteristics (basin morphology) and trends in land cover that may affect stream habitat, Determine the status of and trends in benthic and near-channel habitat in selected wadeable stream reaches (e.g., bed sediment, geomorphic channel units, and large woody debris), Determine the status of and trends in cross-sectional morphology, longitudinal gradient, and sinuosity of selected wadeable stream reaches. Between June 11 and 14, 2018, data were collected at Congaree National Park to characterize the in-stream and near-channel habitat within stream reaches on Cedar Creek (CONG001, CONG002, and CONG003) and McKenzie Creek (CONG004). These data, along with the analysis of remotely sensed geographic information system (GIS) data, are presented in this report to describe and compare the watershed-, reach-, and transect-scale characteristics of these four stream reaches to each other and to selected similar-sized stream reaches at Ocmulgee Mounds National Historical Park, Kennesaw Mountain National Battlefield Park, and Chattahoochee National Recreation Area. Surveyed stream reaches at Congaree NP were compared to those previously surveyed in other parks in order to provide regional context and aid in interpretation of results. edar Creek’s watershed (CONG001, CONG002, and CONG003) drains nearly 200 square kilometers (77.22 square miles [mi2]) of the Congaree River Valley Terrace complex and upper Coastal Plain to the north of the park (Shelley 2007a, 2007b). Cedar Creek’s watershed has low slope and is covered mainly by forests and grasslands. Cedar Creek is designated an “Outstanding Resource Water” by the state of South Carolina (S.C. Code Regs. 61–68 [2014] and S.C. Code Regs. 61–69 [2012]) from the boundary of the park downstream to Wise Lake. Cedar Creek ‘upstream’ (CONG001) is located just downstream (south) of the park’s Bannister Bridge canoe landing, which is located off Old Bluff Road and south of the confluence with Meyers Creek. Cedar Creek ‘middle’ and Cedar Creek ‘downstream’ (CONG002 and CONG003, respectively) are located downstream of Cedar Creek ‘upstream’ where Cedar Creek flows into the relatively flat backswamp of the Congaree River flood plain. Based on the geomorphic and land cover characteristics of the watershed, monitored reaches on Cedar Creek are likely to flood often and drain slowly. Flooding is more likely at Cedar Creek ‘middle’ and Cedar Creek ‘downstream’ than at Cedar Creek ‘upstream.’ This is due to the higher (relative to CONG001) connectivity between the channels of the lower reaches and their out-of-channel areas. Based on bed sediment characteristics, the heterogeneity of geomorphic channel units (GCUs) within each reach, and the abundance of large woody debris (LWD), in-stream habitat within each of the surveyed reaches on Cedar Creek (CONG001–003) was classified as ‘fair to good.’ Although, there is extensive evidence of animal activity...
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Wyndham, Amber, Emile Elias, Joel Brown, Michael Wilson et Albert Rango. Drought Vulnerability Assessment to Inform Grazing Practices on Rangelands of Southeastern Colorado’s Major Land Resource Area 69. USDA Southwest Climate Hub, juillet 2018. http://dx.doi.org/10.32747/2018.6947062.ch.
Texte intégralRésumé :
Increased climate variability, including more frequent and intense drought, is projected for the southwestern region of the United States. Increased temperatures and reduced precipitation lower soil water availability, resulting in decreased plant productivity and altering species composition, which may affect forage quality and quantity. Reduced forage quality and increased heat stress attributable to warmer temperatures could lead to decreased livestock performance in this system, which is extensively used for livestock grazing. Mitigating the effects of increasing drought is critical to social and ecological stability in the region. Reduced stocking rates, change in livestock breeds and/or grazing practices
are general recommendations that could be implemented to cope with increased climatic stress. Ecological Sites and their associated state–and-transition models (STMs) are tools to help land managers implement and evaluate responses to disturbances. The projected change in climate will vary depending upon geographic location. Vulnerability assessments and adaptation strategies are needed at the local level to inform local management decisions and help ameliorate the effects of climate change on rangelands. The United States Department of Agriculture (USDA) Southwest Climate Hub and Natural Resources Conservation Service (NRCS) worked together to produce this drought vulnerability
assessment at the Major Land Resource Area (MLRA) level, based on ecological sites and state-and-transition models that will help landowners and government agencies to identify and develop adaptation options for drought on rangelands. The assessment illustrates how site-specific information can be used to help minimize the effects of drought on rangelands and support informed decision-making for the selection of management adaptations within MLRA 69.
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Library, Spring. Vitiligo and the Social Stigma Attached to It. Spring Library, décembre 2020. http://dx.doi.org/10.47496/sl.blog.15.
Texte intégralRésumé :
The well-established theory states that vitiligo is usually initiated by a trigger including hormonal changes, psychological trauma, and stress, exposure to chemicals, or trauma to the skin and sufferers have to cope-up with a lot of social stigmas.
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Wyndham, Amber, Emile Elias, Joel R. Brown, Michael A. Wilson et Albert Rango. Drought Vulnerability Assessment to Inform Grazing Practices on Rangelands in Southeast Arizona and Southwest New Mexico’s Major Land Resource Area 41. United States. Department of Agriculture. Southwest Climate Hub, août 2018. http://dx.doi.org/10.32747/2018.6818230.ch.
Texte intégralRésumé :
Increased climate variability, including more frequent and intense drought, is projected for the southwestern region of the United States. Increased temperatures and reduced precipitation lower soil water availability, resulting in decreased plant productivity and altered species composition, which may affect forage quality and quantity. Reduced forage quality and increased heat stress attributable to warmer temperatures could lead to decreased livestock performance in this system, which is extensively used for livestock grazing. Mitigating the effects of increasing drought is critical to social and ecological stability in the region. Reduced stocking rates and/or a change in livestock breeds and/or grazing practices are general recommendations that could be implemented to cope with increased climatic stress. Ecological Sites (ESs) and their associated state-and-transition models (STMs) are tools to help land managers implement and evaluate responses to disturbances. The projected change in climate will vary depending upon geographic location. Vulnerability assessments and adaptation strategies are necessary at the local level to inform local management decisions and help to ameliorate the effects of climate change on rangelands. The USDA Southwest Climate Hub and the Natural Resources Conservation Service (NRCS) worked together to produce this drought vulnerability assessment at the Major Land Resource Area (MLRA) level: it is based on ESs/STMs that will help landowners and government agencies to identify and develop adaptation options for drought on rangelands. The assessment illustrates how site-specific information can be used to help minimize the effects of drought on rangelands and to support informed decision-making for selecting management adaptations within MLRA 41.
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Wyndham, Amber, Emile Elias, Joel R. Brown, Michael A. Wilson et Albert Rango. Drought Vulnerability Assessment to Inform Grazing Practices on Rangelands of Southeastern Colorado’s Major Land Resource Area 69. United States. Department of Agriculture. Southwest Climate Hub, janvier 2018. http://dx.doi.org/10.32747/2018.6876399.ch.
Texte intégralRésumé :
Increased climate variability, including more frequent and intense drought, is projected for the southwestern region of the United States. Increased temperatures and reduced precipitation lower soil water availability resulting in decreased plant productivity and altering species composition which may affect forage quality and quantity. Reduced forage quality and increased heat stress attributable to warmer temperatures could lead to decreased livestock performance in this system, which is extensively used for livestock grazing. Mitigating the effects of increasing drought is critical to social and ecological stability in the region. Reduced stocking rates, change in livestock breeds and/or grazing practices are general recommendations that could be implemented to cope with increased climatic stress. Ecological Sites (ESs) and their associated state and transition models (STMs) are tools to help land managers implement and evaluate responses to disturbances. The projected change in climate will vary depending on geographic location. Vulnerability assessments and adaptation strategies are needed at the local level to inform local management decisions and help ameliorate the effects of climate change on rangelands. The USDA Southwest Climate Hub and Natural Resources Conservation Service (NRCS) worked together to produce this drought vulnerability assessment at the Major Land Resource Area (MLRA) level based on ESs/STMs that will help landowners and government agencies identify and develop adaptation options for drought on rangelands. The assessment illustrates how site-specific information can be used to help minimize the effects of drought on rangelands and support informed decision-making for selecting management adaptations within MLRA 69.
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Wyndham, Amber, Emile Elias, Joel Brown, Michael Wilson et Albert Rango Rango. Drought Vulnerability Assessment to Inform Grazing Practices on Rangelands in Southeast Arizona and Southwest New Mexico’s Major Land Resource Area 41. USDA Southwest Climate Hub, août 2018. http://dx.doi.org/10.32747/2018.6947060.ch.
Texte intégralRésumé :
Increased climate variability, including more frequent and intense drought, is projected for the southwestern region of the United States. Increased temperatures and reduced precipitation lower soil water availability, resulting in decreased plant productivity and altered species composition, which may affect forage quality and quantity. Reduced forage quality and increased heat stress attributable to warmer temperatures could lead to decreased livestock performance in this system, which is extensively used for livestock grazing. Mitigating the effects of increasing drought is critical to social and ecological stability in the region. Reduced stocking rates and/or a change in livestock breeds and/or grazing
practices are general recommendations that could be implemented to cope with increased climatic stress. Ecological Sites (ESs) and their associated state-and-transition models (STMs) are tools to help land managers implement and evaluate responses to disturbances. The projected change in climate will vary depending upon geographic location. Vulnerability assessments and adaptation strategies are necessary at the local level to inform local management decisions and help to ameliorate the effects of climate change on rangelands. The USDA Southwest Climate Hub and the Natural Resources Conservation Service (NRCS) worked together to produce this drought vulnerability assessment at the
Major Land Resource Area (MLRA) level: it is based on ESs/STMs that will help landowners and government agencies to identify and develop adaptation options for drought on rangelands. The assessment illustrates how site-specific information can be used to help minimize the effects of drought on rangelands and to support informed decision-making for selecting management adaptations within MLRA 41.
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Wyndham, Amber, Emile Elias, Joel Brown, Michael Wilson et Albert Rango. Drought Vulnerability Assessment to Inform Grazing Practices on Rangelands of Southeastern Colorado’s Major Land Resource Area 69. USDA Southwest Climate Hub, mars 2018. http://dx.doi.org/10.32747/2018.6965584.ch.
Texte intégralRésumé :
Increased climate variability, including more frequent and intense drought, is projected for the southwestern region of the United States. Increased temperatures and reduced precipitation lower soil water availability resulting in decreased plant productivity and altering species composition which may affect forage quality and quantity. Reduced forage quality and increased heat stress attributable to warmer temperatures could lead to decreased livestock performance in this system, which is extensively used for livestock grazing. Mitigating the effects of increasing drought is critical to social and ecological stability in the region. Reduced stocking rates, change in livestock breeds and/or grazing practices are general recommendations that could be implemented to cope with increased climatic stress. Ecological Sites (ESs) and their associated state and transition models (STMs) are tools to help land managers implement and evaluate responses to disturbances. The projected change in climate will vary depending on geographic location. Vulnerability assessments and adaptation strategies are needed at the local level to inform local management decisions and help ameliorate the effects of climate change on rangelands. The USDA Southwest Climate Hub and Natural Resources Conservation Service (NRCS) worked together to produce this drought vulnerability assessment at the Major Land Resource Area (MLRA) level based on ESs/STMs that will help landowners and government agencies identify and develop adaptation options for drought on rangelands. The assessment illustrates how site-specific information can be used to help minimize the effects of drought on rangelands and support informed decision-making for selecting management adaptations within MLRA 69.
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Walsh, Margaret, Peter Backlund, Lawrence Buja, Arthur DeGaetano, Rachel Melnick, Linda Prokopy, Eugene Takle, Dennis Todey et Lewis Ziska. Climate Indicators for Agriculture. United States. Department of Agriculture. Climate Change Program Office, juillet 2020. http://dx.doi.org/10.32747/2020.7201760.ch.
Texte intégralRésumé :
The Climate Indicators for Agriculture report presents 20 indicators of climate change, carefully selected across multiple agricultural production types and food system elements in the United States. Together, they represent an overall view of how climate change is influencing U.S. agriculture and food systems. Individually, they provide useful information to support management decisions for a variety of crop and livestock production systems. The report includes multiple categories of indicators, including physical indicators (e.g., temperature, precipitation), crop and livestock (e.g., animal heat stress), biological indicators (e.g., pests), phenological indicators (e.g. seasonality), and socioeconomic indicators (e.g., total factor productivity).
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Johnson, Sarah, Michael Sinclair, Emily Leonard et Forrest Rosenbower. Development of strategies for monitoring and managing sandscape vegetation, with an assessment of declining vegetation in the Apostle Islands National Lakeshore. National Park Service, avril 2022. http://dx.doi.org/10.36967/nrr-2293187.
Texte intégralRésumé :
Coastal dune habitats such as those of the Apostle Islands National Lakeshore (APIS) are regionally rare habitats of global and state-wide concern. Their dynamic, sandy landforms provide habitat for unique species specifically adapted to frequent disturbance, drought, and other stresses. Despite having disturbance-driven life histories, these species are at risk due to increased visitor use of sandscape habitats and environmental change. Resource managers at APIS have long understood the values of these sandscapes and threats presented by recreational trampling, but more recently they have recognized the precarious position that these coastal habitats are in due to their proximity to the lake and exposure to weather-related phenomena linked with long-term climate change. In recognition of emerging threats and the need to track impacts of these threats, park managers initiated a revision of their methods for monitoring sandscape vegetation. We applied these methods to 15 sandscape locations within the national lakeshore in 2014. Here, we outline what these revisions to the methods were, assess the current status of sandscape structure and composition, assess the utility of data collected with these methods, provide suggestions for further revisions of the sampling method, outline a two-tiered sampling approach for future monitoring, and we provide management recommendations. In a second section of the report, we provide a focused assessment of the size and health of Juniperus communis (common juniper), a target species of concern in these sandscape communities after it was observed by park managers to be dying or stressed on Michigan Island. Our assessments include the status of J. communis across all sandscapes monitored in 2014, and an analysis of change over time since 2012 in the health of J. communis on Michigan, Outer, and Stockton Islands. We provide evidence of impacts by rodents on foliar dieback, primarily on Michigan Island, and we discuss possible interactions with the non-native pale juniper web-worm (Aethes rutilana) and with climate change.