WorldWideScience

Sample records for subduction poverty indentation

  1. Poverty

    OpenAIRE

    Marks, Stephen P.

    2017-01-01

    This chapter addresses the challenge posed by poverty to the protection of human rights. Human rights define the entitlements considered necessary for a life of dignity in society, including the right to an adequate standard of living, that is, the right to be free from poverty. At this high level of abstraction, the elimination of poverty and realization of human rights are similar in that both clarify what needs to be done so that all human beings enjoy minimal standards of a decent existen...

  2. Analysis of indentation creep

    Science.gov (United States)

    Don S. Stone; Joseph E. Jakes; Jonathan Puthoff; Abdelmageed A. Elmustafa

    2010-01-01

    Finite element analysis is used to simulate cone indentation creep in materials across a wide range of hardness, strain rate sensitivity, and work-hardening exponent. Modeling reveals that the commonly held assumption of the hardness strain rate sensitivity (mΗ) equaling the flow stress strain rate sensitivity (mσ...

  3. Cable indenter aging monitor

    International Nuclear Information System (INIS)

    Shook, T.A.; Gardner, J.B.

    1988-07-01

    This project was undertaken to develop a hand-held, nondestructive test device to assess the aged condition of electrical cable by in situ measurement of mechanical properties of polymeric jackets and insulations. The device is an indenter similar to those used to make hardness measurements. Comparison of measurements made on installed cables with previous measurements serving as baseline aging/mechanical property data will determine the state of aging of the field cables. Such a device will be valuable in nuclear and fossil plant life extension programs. Preliminary laboratory tests on cables covered with ethylene propylene rubber (EPR) and chlorosulfated polyethylene (CSPE) point to the measurement of the rate of force increase resulting from constant rate deformation as having the best correlation with progressive thermal aging. This first phase of the work has demonstrated the technical feasibility of the method. A second phase will include the generation of additional groundwork data and the design of the portable indenter for in situ plant measurements

  4. Blunt indentation of core graphite

    International Nuclear Information System (INIS)

    Hartley, M.; McEnaney, B.

    1996-01-01

    Blunt indentation experiments were carried out on unoxidized and thermally oxidised IM1-24 graphite as a model to simulate local point stresses acting on graphite moderator bricks. Blunt indentation of unoxidized graphite initiates cracks close to the region of maximum tensile stress at the edge of the indentation. Cracks propagate and converge to form a cone of material. Failure is catastrophic, typically forming three pieces of graphite and ejecting the cone referred to above. The failure mode under indentation loading for highly oxidised graphite (weigh loss > 40%) is different from that for the unoxidized graphite. There is no longer a distinct crack path, the indentation is much deeper than in the case of the unoxidized graphite, and there is a region of crushed debris beneath the indentation, producing a crater-like structure. The reduction in the compressive fracture stress, σ cf , under indentation loading with increasing fractional weight loss on oxidation, x, can be fitted to σ cf /σ 0 = exp-[5.2x] where σ 0 is the compressive fracture stress of the unoxidized graphite. This indicates that the effect of thermal oxidation on indentation fracture stress is more severe than the effects of radiolytic oxidation on conventional strengths of nuclear graphites. (author). 8 refs, 12 figs

  5. Residual stresses around Vickers indents

    International Nuclear Information System (INIS)

    Pajares, A.; Guiberteau, F.; Steinbrech, R.W.

    1995-01-01

    The residual stresses generated by Vickers indentation in brittle materials and their changes due to annealing and surface removal were studied in 4 mol% yttria partially stabilized zirconia (4Y-PSZ). Three experimental methods to gain information about the residual stress field were applied: (i) crack profile measurements based on serial sectioning, (ii) controlled crack propagation in post indentation bending tests and (iii) double indentation tests with smaller secondary indents located around a larger primary impression. Three zones of different residual stress behavior are deduced from the experiments. Beneath the impression a crack free spherical zone of high hydrostatic stresses exists. This core zone is followed by a transition regime where indentation cracks develop but still experience hydrostatic stresses. Finally, in an outward third zone, the crack contour is entirely governed by the tensile residual stress intensity (elastically deformed region). Annealing and surface removal reduce this crack driving stress intensity. The specific changes of the residual stresses due to the post indentation treatments are described and discussed in detail for the three zones

  6. Poverty Reduction

    OpenAIRE

    Ortiz, Isabel

    2007-01-01

    The paper reviews poverty trends and measurements, poverty reduction in historical perspective, the poverty-inequality-growth debate, national poverty reduction strategies, criticisms of the agenda and the need for redistribution, international policies for poverty reduction, and ultimately understanding poverty at a global scale. It belongs to a series of backgrounders developed at Joseph Stiglitz's Initiative for Policy Dialogue.

  7. Indentation Depth Dependent Mechanical Behavior in Polymers

    OpenAIRE

    Alisafaei, Farid; Han, Chung-Souk

    2015-01-01

    Various experimental studies have revealed size dependent deformation of materials at micro and submicron length scales. Among different experimental methods, nanoindentation testing is arguably the most commonly applied method of studying size effect in various materials where increases in the hardness with decreasing indentation depth are usually related to indentation size effects. Such indentation size effects have been observed in both metals and polymers. While the indentation size effe...

  8. Cathodoluminescence study of vickers indentations in magnesium ...

    African Journals Online (AJOL)

    Vickers diamond pyramid indentations made in single crystal of magnesium oxide (MgO) were examined in an environmental scanning electron microscope interfaced with an AVS-2000 spectrophotometer for luminescence. Three distinct zones around the indentations were identified to exhibit cathodoluminescence, which ...

  9. Indentation of Ellipsoidal and Cylindrical Elastic Shells

    KAUST Repository

    Vella, Dominic

    2012-10-01

    Thin shells are found in nature at scales ranging from viruses to hens\\' eggs; the stiffness of such shells is essential for their function. We present the results of numerical simulations and theoretical analyses for the indentation of ellipsoidal and cylindrical elastic shells, considering both pressurized and unpressurized shells. We provide a theoretical foundation for the experimental findings of Lazarus etal. [following paper, Phys. Rev. Lett. 109, 144301 (2012)PRLTAO0031-9007] and for previous work inferring the turgor pressure of bacteria from measurements of their indentation stiffness; we also identify a new regime at large indentation. We show that the indentation stiffness of convex shells is dominated by either the mean or Gaussian curvature of the shell depending on the pressurization and indentation depth. Our results reveal how geometry rules the rigidity of shells. © 2012 American Physical Society.

  10. Poverty persistence and poverty dynamics

    OpenAIRE

    Martin Biewen

    2014-01-01

    A considerable part of the poverty that is measured in a single period is transitory rather than persistent. In most countries, only a portion of people who are currently poor are persistently poor. People who are persistently poor or who cycle into and out of poverty should be the main focus of anti-poverty policies. Understanding the characteristics of the persistently poor, and the circumstances and mechanisms associated with entry into and exit from poverty, can help to inform governments...

  11. Standard practice for instrumented indentation testing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This practice defines the basic steps of Instrumented Indentation Testing (IIT) and establishes the requirements, accuracies, and capabilities needed by an instrument to successfully perform the test and produce the data that can be used for the determination of indentation hardness and other material characteristics. IIT is a mechanical test that measures the response of a material to the imposed stress and strain of a shaped indenter by forcing the indenter into a material and monitoring the force on, and displacement of, the indenter as a function of time during the full loading-unloading test cycle. 1.2 The operational features of an IIT instrument, as well as requirements for Instrument Verification Annex A1), Standardized Reference Blocks (Annex A2) and Indenter Requirements (Annex A3) are defined. This practice is not intended to be a complete purchase specification for an IIT instrument. 1.3 With the exception of the non-mandatory Appendix X4, this practice does not define the analysis necessary...

  12. A simple model for indentation creep

    Science.gov (United States)

    Ginder, Ryan S.; Nix, William D.; Pharr, George M.

    2018-03-01

    A simple model for indentation creep is developed that allows one to directly convert creep parameters measured in indentation tests to those observed in uniaxial tests through simple closed-form relationships. The model is based on the expansion of a spherical cavity in a power law creeping material modified to account for indentation loading in a manner similar to that developed by Johnson for elastic-plastic indentation (Johnson, 1970). Although only approximate in nature, the simple mathematical form of the new model makes it useful for general estimation purposes or in the development of other deformation models in which a simple closed-form expression for the indentation creep rate is desirable. Comparison to a more rigorous analysis which uses finite element simulation for numerical evaluation shows that the new model predicts uniaxial creep rates within a factor of 2.5, and usually much better than this, for materials creeping with stress exponents in the range 1 ≤ n ≤ 7. The predictive capabilities of the model are evaluated by comparing it to the more rigorous analysis and several sets of experimental data in which both the indentation and uniaxial creep behavior have been measured independently.

  13. Understanding Poverty

    OpenAIRE

    Anne Jerneck

    2015-01-01

    Policies and strategies to fight global environmental degradation, gender inequality, and poverty are often inadequate, ineffective, or insufficient. In response, this article seeks potential synergies and leverage points between three significant interrelated discourses that are often treated separately—development, gender, and environment. Proceeding from a brief history of development thinking and poverty definition...

  14. Understanding Poverty

    Directory of Open Access Journals (Sweden)

    Anne Jerneck

    2015-11-01

    Full Text Available Policies and strategies to fight global environmental degradation, gender inequality, and poverty are often inadequate, ineffective, or insufficient. In response, this article seeks potential synergies and leverage points between three significant interrelated discourses that are often treated separately—development, gender, and environment. Proceeding from a brief history of development thinking and poverty definitions, I describe indicators, strategies, and approaches to poverty reduction and gender equality. Second, I analyze how targeting, mainstreaming, and market-based initiatives all fail both to distinguish empirical from analytical gender and to incorporate environment and gender into development policy and action—despite their key role in meeting the normative goal of poverty reduction. Third, through a political-ecology lens, I suggest an integrated approach to poverty, inequality, and socioenvironmental challenges that arise at the intersections of development, gender, and environment, and for that, I draw examples from research on social and environmental change and action in sub-Saharan Africa.

  15. The difference of phase distributions in silicon after indentation with Berkovich and spherical indenters

    International Nuclear Information System (INIS)

    Zarudi, I.; Zhang, L.C.; Cheong, W.C.D.; Yu, T.X.

    2005-01-01

    This study analyses the microstructure of monocrystalline silicon after indentation with a Berkovich and spherical indenter. Transmission electron microscopy on cross section view samples was used to explore the detailed distributions of various phases in the subsurfaces of indented silicon. It was found that an increase of the P max would promote the growth of the crystalline R8/BC8 phase at the bottom of the deformation zone. Microcracks were always generated in the range of the P max studied. It was also found that the deformation zones formed by the Berkovich and spherical indenters have very different phase distribution characteristics. A molecular dynamics simulation and finite element analysis supported the experimental observations and suggested that the distribution of the crystalline phases in the transformation zone after indentation was highly stress-dependent

  16. Indentation of aluminium foam at low velocity

    Directory of Open Access Journals (Sweden)

    Shi Xiaopeng

    2015-01-01

    Full Text Available The indentation behaviour of aluminium foams at low velocity (10 m/s ∼ 30 m/s was investigated both in experiments and numerical simulation in this paper. A flat-ended indenter was used and the force-displacement history was recorded. The Split Hopkinson Pressure bar was used to obtain the indentation velocity and forces in the dynamic experiments. Because of the low strength of the aluminium foam, PMMA bar was used, and the experimental data were corrected using Bacon's method. The energy absorption characteristics varying with impact velocity were then obtained. It was found that the energy absorption ability of aluminium foam gradually increases in the quasi-static regime and shows a significant increase at ∼10 m/s velocity. Numerical simulation was also conducted to investigate this process. A 3D Voronoi model was used and models with different relative densities were investigated as well as those with different failure strain. The indentation energy increases with both the relative density and failure strain. The analysis of the FE model implies that the significant change in energy absorption ability of aluminium foam in indentation at ∼10 m/s velocity may be caused by plastic wave effect.

  17. Law's Poverty

    Directory of Open Access Journals (Sweden)

    Joel M Modiri

    2015-08-01

    Full Text Available This article adopts an analysis that explicitly politicises poverty and relates it to the concrete history of racialised capitalism and structural inequality that defined colonialism and apartheid and continues to persist and intensify in "post"-apartheid South Africa. Rather than formulating racialised poverty in legalist, economist or managerial terms, it should rather be understood as a form of oppression that comprises exploitation, marginalisation, powerlessness, cultural imperialism and violence. Such a formulation would make social structure, historical injustice and power central and would also allow for poverty to be grasped beyond a purely distributive logic by bringing to light the non-distributive, non-economic dimensions of poverty. Comprehending poverty in this way, as not only a question of economic distribution and empowerment, but also one of ethical, moral and even ontological recognition necessitates an enquiry into the emancipatory force of rights. Given their centrality in political and social discourse and in legal scholarship on poverty, it is worth considering whether and to what extent rights can be utilised in the struggle against (racialised poverty.

  18. Comparison of Isolated Indentation and Grid Indentation Methods for HVOF Sprayed Cermets

    Science.gov (United States)

    Nohava, Jiří; Haušild, Petr; Houdková, Šárka; Enžl, Radek

    2012-06-01

    This paper compares the results of two approaches of instrumented indentation for characterization of mechanical properties of HVOF coatings. Three types of HVOF sprayed coatings (Cr3C2-NiCr, WC-Co, (Ti, Mo)(C,N)-NiCo) were investigated by the means of isolated nanoindentation and grid indentation methods. The results of the isolated indentation revealed hardness and elastic modulus of the individual phases in very good agreement with the corresponding bulk material. The grid indentation method, based on statistical evaluation of a large number of indentations, was influenced by the carbide-matrix interface, which gave rise to a third peak apart from the two peaks corresponding to the carbides and metallic matrix. As a consequence, the bimodal Gaussian fit was insufficient and a trimodal fit had to be used. The results extracted from low load grid nanoindentations were quite close to the results of isolated indentations whereas higher load grid nanoindentation revealed overall properties of the coating.

  19. Double subduction of continental lithosphere, a key to form wide plateau

    Science.gov (United States)

    Replumaz, Anne; Funiciello, Francesca; Reitano, Riccardo; Faccenna, Claudio; Balon, Marie

    2016-04-01

    The mechanisms involved in the creation of the high and wide topography, like the Tibetan Plateau, are still controversial. In particular, the behaviour of the indian and asian lower continental lithosphere during the collision is a matter of debate, either thickening, densifying and delaminating, or keeping its rigidity and subducting. But since several decades seismicity, seismic profiles and global tomography highlight the lithospheric structure of the Tibetan Plateau, and make the hypotheses sustaining the models more precise. In particular, in the western syntaxis, it is now clear that the indian lithosphere subducts northward beneath the Hindu Kush down to the transition zone, while the asian one subducts southward beneath Pamir (e.g. Negredo et al., 2007; Kufner et al., 2015). Such double subduction of continental lithospheres with opposite vergence has also been inferred in the early collision time. Cenozoic volcanic rocks between 50 and 30 Ma in the Qiangtang block have been interpreted as related to an asian subduction beneath Qiangtang at that time (De Celles et al., 2011; Guillot and Replumaz, 2013). We present here analogue experiments silicone/honey to explore the subduction of continental lithosphere, using a piston as analogue of far field forces. We explore the parameters that control the subductions dynamics of the 2 continental lithospheres and the thickening of the plates at the surface, and compare with the Tibetan Plateau evolution. We show that a continental lithosphere is able to subduct in a collision context, even lighter than the mantle, if the plate is rigid enough. In that case the horizontal force due to the collision context, modelled by the piston push transmitted by the indenter, is the driving force, not the slab pull which is negative. It is not a subduction driving by the weight of the slab, but a subduction induced by the collision, that we could call "collisional subduction".

  20. Indentation of elastically soft and plastically compressible solids

    DEFF Research Database (Denmark)

    Needleman, A.; Tvergaard, Viggo; Van der Giessen, E.

    2015-01-01

    The effect of soft elasticity, i.e., a relatively small value of the ratio of Young's modulus to yield strength and plastic compressibility on the indentation of isotropically hardening elastic-viscoplastic solids is investigated. Calculations are carried out for indentation of a perfectly sticking...... the ratio of nominal indentation hardness to yield strength. A linear relation is found between the nominal indentation hardness and the logarithm of the ratio of Young's modulus to yield strength, but with a different coefficient than reported in previous studies. The nominal indentation hardness decreases...

  1. Poverty Comparisons with Endogenous Absolute Poverty Lines

    OpenAIRE

    Simler, Kenneth R.; Arndt, Channing

    2006-01-01

    The objective of measuring poverty is usually to make comparisons over time or between two or more groups. Comm on statistical inference methods are used to determine whether an apparent difference in measured poverty is statistically significant. Studies of relative poverty have long recognized that when the poverty line is calculated from sample survey data, both the variance of the poverty line and the variance of the welfare metric contribute to the variance of the poverty estimate. In co...

  2. Rebound indentation problem for a viscoelastic half-space and axisymmetric indenter - Solution by the method of dimensionality reduction

    Science.gov (United States)

    Argatov, Ivan I.; Popov, Valentin L.

    2016-08-01

    The method of dimensionality reduction (MDR) is extended for the axisymmetric frictionless unilateral Hertz-type contact problem for a viscoelastic half-space and an arbitrary axisymmetric rigid indenter under the assumption that an arbitrarily evolving in time circular contact area remains singly connected during the whole process of indentation. In particular, the MDR is applied to study in detail the so-called rebound indentation problem, where the contact radius has a single maximum. It is shown that the obtained closed-form analytical solution for the rebound indentation displacement (recorded in the recovery phase, when the contact force vanishes) does not depend on the indenter shape.

  3. 3D geodynamic models for the development of opposing continental subduction zones: The Hindu Kush-Pamir example

    Science.gov (United States)

    Liao, Jie; Gerya, Taras; Thielmann, Marcel; Webb, A. Alexander G.; Kufner, Sofia-Katerina; Yin, An

    2017-12-01

    The development of opposing continental subduction zones remains scantly explored in three dimensions. The Hindu Kush-Pamir orogenic system at the western end of the Himalayan orogen provides a rare example of continental collision linked to two opposing intra-continental subduction zones. The subducted plates feature a peculiar 3D geometry consisting of two distinct lithospheric fragments with different polarities, subduction angles and slab-curvatures beneath the Hindu Kush and Pamir, respectively. Using 3D geodynamic modeling, we simulate possible development of two opposing continental subduction zones to understand the dynamic evolution of the Hindu Kush-Pamir orogenic system. Our geodynamic model reproduces the major tectonic elements observed: (1) the deeper subduction depth, the steeper dip angle and the southward offset of the Hindu Kush subduction zone relative to the Pamir naturally occur if convergence direction of the subducting Indian plate and dip-direction of the Hindu Kush subduction zone match. (2) The formation of the highly asymmetrically curved Pamir region and the south-dipping subduction is promoted by the initial geometry of the indenting Indian lithosphere together with the existence of a major strike-slip fault on the eastern margin of the Pamir region. (3) Subduction of only the lower continental crust during continental collision can occur if the coupling between upper and lower crusts is weak enough to allow a separation of these two components, and that (4) the subduction of mainly lower crust then facilitates that conditions for intermediate-depth seismicity can be reached. (5) The secondary tectonic features modeled here such as strike-slip-fault growth, north-northwest striking extension zone, and lateral flow of the thickened ductile upper crust are comparable to the current tectonics of the region. (6) Model results are further compared to the potentially similar orogenic system, i.e., the Alpine orogen, in terms of the curved

  4. Analysis of Indentation-Derived Power-Law Creep Response

    Science.gov (United States)

    Martinez, Nicholas J.; Shen, Yu-Lin

    2016-03-01

    The use of instrumented indentation to characterize power-law creep is studied by computational modeling. Systematic finite element analyses were conducted to examine how indentation creep tests can be employed to retrieve the steady-state creep parameters pertaining to regular uniaxial loading. The constant indentation load hold and constant indentation-strain-rate methods were considered, first using tin (Sn)-based materials as a model system. The simulated indentation-strain rate-creep stress relations were compared against the uniaxial counterparts serving as model input. It was found that the constant indentation-strain-rate method can help establish steady-state creep, and leads to a more uniform behavior than the constant-load hold method. An expanded parametric analysis was then performed using the constant indentation-strain-rate method, taking into account a wide range of possible power-law creep parameters. The indentation technique was found to give rise to accurate stress exponents, and a certain trend for the ratio between indentation strain rate and uniaxial strain rate was identified. A contour-map representation of the findings serves as practical guidance for determining the uniaxial power-law creep response based on the indentation technique.

  5. Subduction and Slab Advance at Orogen Syntaxes: Predicting Exhumation Rates and Thermochronometric Ages with Numerical Modeling

    Science.gov (United States)

    Nettesheim, Matthias; Ehlers, Todd A.; Whipp, David M.

    2017-04-01

    The change in plate boundary orientation and subducting plate geometry along orogen syntaxes may have major control on the subduction and exhumation dynamics at these locations. Previous work documents that the curvature of subducting plates in 3D at orogen syntaxes forces a buckling and flexural stiffening of the downgoing plate. The geometry of this stiffened plate region, also called indenter, can be observed in various subduction zones around the world (e.g. St. Elias Range, Alaska; Cascadia, USA; Andean syntaxis, South America). The development of a subducting, flexurally stiffened indenter beneath orogen syntaxes influences deformation in the overriding plate and can lead to accelerated and focused rock uplift above its apex. Moreover, the style of deformation in the overriding plate is influenced by the amount of trench or slab advance, which is the amount of overall shortening not accommodated by underthrusting. While many subduction zones exhibit little to no slab advance, the Nazca-South America subduction and especially the early stages of the India-Eurasia collision provide end-member examples. Here, we use a transient, lithospheric-scale, thermomechanical 3D model of an orogen syntaxis to investigate the effects of subducting a flexurally stiffened plate geometry and slab advance on upper plate deformation. A visco-plastic upper-plate rheology is used, along with a buckled, rigid subducting plate. The free surface of the thermomechanical model is coupled to a landscape evolution model that accounts for erosion by fluvial and hillslope processes. The cooling histories of exhumed rocks are used to predict the evolution of low-temperature thermochronometer ages on the surface. With a constant overall shortening for all simulations, the magnitude of slab advance is varied stepwise from no advance, with all shortening accommodated by underthrusting, to full slab advance, i.e. no motion on the megathrust. We show that in models where most shortening is

  6. Urban Poverty in Asia

    OpenAIRE

    Asian Development Bank (ADB); Asian Development Bank (ADB); Asian Development Bank (ADB); Asian Development Bank (ADB)

    2014-01-01

    This report provides an overview of important urban poverty questions. What defines urban poverty and how is urban poverty being measured? What other factors beyond consumption poverty need to be tackled? Who are the urban poor? What relations exist between urban poverty and city size? What linkages exist between urbanization, income, and urban poverty? What policy responses to urban poverty are implemented in selected Asian countries? The report served as a background study for the Internati...

  7. Indentation Behavior of Permanently Densified Oxide Glasses

    DEFF Research Database (Denmark)

    Bechgaard, Tobias Kjær; Januchta, Kacper; Kapoor, Saurabh

    -induced changes in density, structure, and indentation behavior of a range of oxide glasses, including silicates, borates, and phosphates. The effect of compression on the structure is analyzed through both Raman and NMR spectroscopy, while the mechanical properties are investigated using Vickers micro......Hot isostatic compression can be used as a post treatment method to tune the properties of glass materials as well as to obtain improved understanding of the pressure-induced structural changes and densification mechanisms, e.g., during sharp contact loading. Here, we review the pressure...... number distribution of network formers, the number of non-bridging oxygens, and the packing efficiency in the glasses....

  8. Back-arc Extension: Critical Analisys of Subduction-related and Non Subduction-related Driving Mechanisms

    Science.gov (United States)

    Mantovani, E.; Viti, M.; Babbucci, D.; Tamburelli, C.; Albarello, D.

    It is argued that the opening of back arc basins can hardly be explained as an effect of subduction related forces, since this kind of interpretation has not yet provided plausible explanations for several major features of such processes in the world. In particular, it is not clear why back arc extension occurs in some subduction zones and not in others, why extension ceased in zones where subduction has remained active, why the arcs associated with back arc basins are often characterized by a strongly curved shape, why arc-trench-back arc systems do not develop along the entire length of consuming borders and why no significant correlation can be recognized between any parameter of subduction processes and the occurrence of back arc extension. In addition, modelling experiments indicate that the magnitude of the tensional stress induced in the overriding plate by subduction-related forces is significantly lower than the lithospheric strength. These problems are discussed, in particular, for three subduction-related interpretations, the "slab-pull", the "corner flow" and the "sea an- chor" models, which seem to be the most quoted in literature. It is then argued that possible solutions of the above problems may be provided by the extrusion model, which postulates that back arc basins are generated by the forced separation of the arc from the overriding plate, along a sector of the consuming border. This separa- tion is generally caused by the oblique indentation of strong and buoyant structures against the accretionary belt. In this view, subduction and back arc extension are not causally linked one to the other, but rather represent simultaneous effects of the lateral migration of the arc, driven by plate convergence. It is pointed out that the conditions required for the occurrence of this kind of mechanism may be recognized in the tec- tonic contexts where back arc basins developed in the wake of arc-trench migrating systems. On the other hand, in the zones

  9. On size-effects in single crystal wedge indentation

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2012-01-01

    Wedge indentation in single crystals is studied numerically, with emphasis on size-effects on the micron scale. Under the assumption of a perfectly sharp wedge indenter, a linear relationship between indentation force and indentation depth would be predicted from conventional theories lacking con...... are included in the model due to the addition of gradient terms in both the free energy as well as through a dissipation potential. The finite element solution method is presented, which delivers the slip-rate field and the velocity-field based on two minimum principles.......Wedge indentation in single crystals is studied numerically, with emphasis on size-effects on the micron scale. Under the assumption of a perfectly sharp wedge indenter, a linear relationship between indentation force and indentation depth would be predicted from conventional theories lacking...... constitutive length parameters to model sizeeffects. The problem is studied numerically using a strain gradient crystal visco-plasticity theory formulated along the lines proposed by Fleck andWillis (2009). It is shown how the force-indentation relation is affected due to size-dependence in the material. Size-effects...

  10. Indentation and Observation of Anisotropic Soft Tissues Using an Indenter Device

    Directory of Open Access Journals (Sweden)

    Parinaz ASHRAFI

    2015-01-01

    Full Text Available Soft tissues of human body have complex structures and different mechanical behaviors than those of traditional engineering materials. There is a great urge to understand tissue behavior of human body. Experimental data is needed for improvement of soft tissue modeling and advancement in implants and prosthesis, as well as diagnosis of diseases. Mechanical behavior and responses change when tissue loses its liveliness and viability. One of the techniques for soft tissue testing is indentation, which is applied on live tissue in its physiological environment. Indentation affords several advantages over other types of tests such as uniaxial tension, biaxial tension, and simple shear and suction, thus it is of interest to develop new indentation techniques from which more valid data can be extracted. In this study a new indenter device was designed and constructed. Displacement and force rate cyclic loading, and relaxation experiments were conducted on human arm. The in-vivo force rate controlled cyclic loading test method which is novel is compared with the traditional displacement controlled cyclic loading tests. Anisotropic behavior of tissue cannot be determined by axisymmetric tips, therefore ellipsoid tips were used for examining anisotropy and inplane material direction of bulk soft tissues

  11. Introduction: Subduction's sharpest arrow

    Science.gov (United States)

    Eichelberger, John C.

    In the center of the 6000-km reach of Kurile-Kamchatka-Aleutian-Alaska subduction is arguably Earth's most remarkable subduction cusp. The Kamchatka-Aleutian junction is a sharp arrowhead mounted on the shaft of the Emperor Seamount Chain. This collection of papers provides context, definition, and suggestions for the origin of the junction, but a comprehensive understanding remains elusive, in part because of the newness of international collaborations. Necessary cross-border syntheses have been impeded by the adversarial international relations that characterized the 20th century. For much of this period, Kamchatka and the Kurile Islands were part of the Soviet Union, a mostly closed country. The entire region was swept by World War II, abundant remnants of which are wrecked ships and planes, unexploded ordnance, and Rommel stakes.

  12. The interplay between subduction and lateral extrusion: A case study for the European Eastern Alps based on analogue models

    Science.gov (United States)

    van Gelder, I. E.; Willingshofer, E.; Sokoutis, D.; Cloetingh, S. A. P. L.

    2017-08-01

    A series of analogue experiments simulating intra-continental subduction contemporaneous with lateral extrusion of the upper plate are performed to study the interference between these two processes at crustal levels and in the lithospheric mantle. The models demonstrate that intra-continental subduction and coeval lateral extrusion of the upper plate are compatible processes leading to similar deformation structures within the extruding region as compared to the classical setup, lithosphere-scale indentation. Strong coupling across the subduction boundary allows for the transfer of stresses to the upper plate, where strain regimes are characterized by crustal thickening near a confined margin and dominated by lateral displacement of material near a weak lateral confinement. The strain regimes propagate laterally during ongoing convergence creating an area of overlap characterized by transpression. When subduction is oblique to the convergence direction, the upper plate is less deformed and as a consequence the amount of lateral extrusion decreases. In addition, strain is partitioned along the oblique plate boundary resulting in less subduction in expense of right lateral displacement close to the weak lateral confinement. Both oblique and orthogonal subduction models have a strong resemblance to lateral extrusion tectonics of the Eastern Alps (Europe), where subduction of the adjacent Adriatic plate beneath the Eastern Alps is debated. Our results imply that subduction of Adria is a valid mechanisms to induce extrusion-type deformation within the Eastern Alps lithosphere. Furthermore, our findings suggest that the Oligocene to Late Miocene structural evolution of the Eastern Alps reflects a phase of oblique subduction followed by a later stage of orthogonal subduction conform a Miocene shift in the plate motion of Adria. Oblique subduction also provides a viable mechanism to explain the rapid decrease in slab length of the Adriatic plate beneath the Eastern Alps

  13. Nucleation at hardness indentations in cold rolled Al

    DEFF Research Database (Denmark)

    Xu, C.L.; Zhang, Yubin; Wu, G.L.

    2015-01-01

    Nucleation of recrystallization near hardness indentations has been investigated in slightly cold rolled high purity aluminium. Samples were cold rolled to 12% and 20% reductions in thickness and indentations were done with two different loads (500 g and 2000 g). The samples were annealed at 300 ...

  14. Crystal plasticity study of single crystal tungsten by indentation tests

    International Nuclear Information System (INIS)

    Yao, Weizhi

    2012-01-01

    Owing to its favorable material properties, tungsten (W) has been studied as a plasma-facing material in fusion reactors. Experiments on W heating in plasma sources and electron beam facilities have shown an intense micro-crack formation at the heated surface and sub-surface. The cracks go deep inside the irradiated sample, and often large distorted areas caused by local plastic deformation are present around the cracks. To interpret the crack-induced microscopic damage evolution process in W, one needs firstly to understand its plasticity on a single grain level, which is referred to as crystal plasticity. In this thesis, the crystal plasticity of single crystal tungsten (SCW) has been studied by spherical and Berkovich indentation tests and the finite element method with a crystal plasticity model. Appropriate values of the material parameters included in the crystal plasticity model are determined by fitting measured load-displacement curves and pile-up profiles with simulated counterparts for spherical indentation. The numerical simulations reveal excellent agreement with experiment. While the load-displacement curves and the deduced indentation hardness exhibit little sensitivity to the indented plane at small indentation depths, the orientation of slip directions within the crystals governs the development of deformation hillocks at the surface. It is found that several factors like friction, indentation depth, active slip systems, misoriented crystal orientation, misoriented sample surface and azimuthal orientation of the indenter can affect the indentation behavior of SCW. The Berkovich indentation test was also used to study the crystal plasticity of SCW after deuterium irradiation. The critical load (pop-in load) for triggering plastic deformation under the indenter is found to depend on the crystallographic orientation. The pop-in loads decrease dramatically after deuterium plasma irradiation for all three investigated crystallographic planes.

  15. AFM indentation study of breast cancer cells

    International Nuclear Information System (INIS)

    Li, Q.S.; Lee, G.Y.H.; Ong, C.N.; Lim, C.T.

    2008-01-01

    Mechanical properties of individual living cells are known to be closely related to the health and function of the human body. Here, atomic force microscopy (AFM) indentation using a micro-sized spherical probe was carried out to characterize the elasticity of benign (MCF-10A) and cancerous (MCF-7) human breast epithelial cells. AFM imaging and confocal fluorescence imaging were also used to investigate their corresponding sub-membrane cytoskeletal structures. Malignant (MCF-7) breast cells were found to have an apparent Young's modulus significantly lower (1.4-1.8 times) than that of their non-malignant (MCF-10A) counterparts at physiological temperature (37 deg. C), and their apparent Young's modulus increase with loading rate. Both confocal and AFM images showed a significant difference in the organization of their sub-membrane actin structures which directly contribute to their difference in cell elasticity. This change may have facilitated easy migration and invasion of malignant cells during metastasis

  16. Analytical method for establishing indentation rolling resistance

    Science.gov (United States)

    Gładysiewicz, Lech; Konieczna, Martyna

    2018-01-01

    Belt conveyors are highly reliable machines able to work in special operating conditions. Harsh environment, long distance of transporting and great mass of transported martials are cause of high energy usage. That is why research in the field of belt conveyor transportation nowadays focuses on reducing the power consumption without lowering their efficiency. In this paper, previous methods for testing rolling resistance are described, and new method designed by authors was presented. New method of testing rolling resistance is quite simple and inexpensive. Moreover it allows to conduct the experimental tests of the impact of different parameters on the value of indentation rolling resistance such as core design, cover thickness, ambient temperature, idler travel frequency, or load value as well. Finally results of tests of relationship between rolling resistance and idler travel frequency and between rolling resistance and idler travel speed was presented.

  17. Intra-continental subduction and contemporaneous lateral extrusion of the upper plate: insights into Alps-Adria interactions

    Science.gov (United States)

    van Gelder, Inge; Willingshofer, Ernst; Sokoutis, Dimitrios; Cloetingh, Sierd

    2017-04-01

    A series of physical analogue experiments were performed to simulate intra-continental subduction contemporaneous with lateral extrusion of the upper plate to study the interferences between these two processes at crustal levels and in the lithospheric mantle. The lithospheric-scale models are specifically designed to represent the collision of the Adriatic microplate with the Eastern Alps, simulated by an intra-continental weak zone to initiate subduction and a weak confined margin perpendicular to the direction of convergence in order to allow for extrusion of the lithosphere. The weak confined margin is the analog for the opening of the Pannonian back-arc basin adjacent to the Eastern Alps with the direction of extension perpendicular to the strike of the orogen. The models show that intra-continental subduction and coeval lateral extrusion of the upper plate are compatible processes. The obtained deformation structures within the extruding region are similar compared to the classical setup where lateral extrusion is provoked by lithosphere-scale indentation. In the models a strong coupling across the subduction boundary allows for the transfer of abundant stresses to the upper plate, leading to laterally varying strain regimes that are characterized by crustal thickening near a confined margin and dominated by lateral displacement of material near a weak lateral confinement. During ongoing convergence the strain regimes propagate laterally, thereby creating an area of overlap characterized by transpression. In models with oblique subduction, with respect to the convergence direction, less deformation of the upper plate is observed and as a consequence the amount of lateral extrusion decreases. Additionally, strain is partitioned along the oblique plate boundary leading to less subduction in expense of right lateral displacement close to the weak lateral confinement. Both oblique and orthogonal subduction models have a strong resemblance to lateral extrusion

  18. Nano indentation of particulate and polymer films

    International Nuclear Information System (INIS)

    Akram, Aisha

    2001-01-01

    A detailed knowledge of the formation and rupture mechanisms of agglomerates is essential when seeking to model equipment designed to produce and process such agglomerated particulate solids. In the work to be described the nano-indentation of two-dimensional agglomerate films was carried out in order to establish a means of identifying the generic breakage mechanisms of agglomerated systems. Data analysis techniques are developed that enable the individual inter-particle junction strengths to be calculated for a model system consisting of rather mono-dispersed colloidal silica particles (20-24 nm diameter) bound with a poly(methyl methacrylate). Applied load and penetration depth data in the range (10 mN and 500 nm respectively) are provided as a function of loading time during a continuous loading. It is argued that these data enable the sequence of the discrete binder bridge failures to be observed thus giving a quantitative indication of the breakage mechanism of this agglomerate system as well as reflect the agglomerate structure. The secondary objective of this work was to produce a range of agglomerates with different mechanical properties, without changing the type and amount of binder or prime particles used in the system. This was achieved by altering the mechanical properties of the binder, poly(methyl methacrylate), by the use of a variety of solvents. From data obtained using nano-indentation on thin films of the treated polymer, brittle and ductile forms of poly(methyl methacrylate) could be distinguished. These trends are reflected, to some degree, in the mechanical response of the agglomerated layers. (author)

  19. Pinpointing Poverty in Hungary

    OpenAIRE

    World Bank Group

    2016-01-01

    The EC and the World Bank, in cooperation with individual EU member states, have developed a set of high-resolution poverty maps. The greater geographical disaggregation of the new poverty maps reveals which parts of these larger regions have particularly high rates of poverty and require greater attention in poverty reduction programs.

  20. Poverty's threat.

    Science.gov (United States)

    1988-03-01

    In the debate on the Report of the World Commission on Environment and Development, chaired by Mrs. Gro Harlem Brundtland, Prime Minister of Norway, delegates to the UN General Assembly asserted that problems generated by the impact of poverty on the environment could not be solved by restricting aid to developing countries unless those countries promised to cease damaging their environment. Rather, most delegates agreed, aid should include the resources which would enable those countries to achieve "sustainable development," i.e., development that does not destroy the environment and deplete natural resources. The United States countered with the opinion that what is needed is not a UN organized "sustainable development program," but rather a grassroots "sustainable development movement" in all countries. Several delegates pointed out that it was the affluent countries which played a large part in the destruction of the environment. The Present of the Maldives, Maumoon Abdul Gayoom, pointed out, for example, that the greenhouse effect, generated by the burning of fossil fuels, would raise the sea level 2 meters, virtually submerging his country. Mrs. Brundtland pointed out that it was not morally acceptable to suggest that the poor remain poor to protect the environment. Governments at all levels, she said, must include environmental concerns in their decision making in all sectors of governmental functioning, e.g., finance, industry, energy, and agriculture.

  1. There is poverty convergence

    OpenAIRE

    Crespo Cuaresma, Jesus; Klasen, Stephan; Wacker, Konstantin M.

    2016-01-01

    Martin Ravallion ("Why Don't We See Poverty Convergence?" American Economic Review, 102(1): 504-23; 2012) presents evidence against the existence of convergence in global poverty rates despite convergence in household mean income levels and the close linkage between income growth and poverty reduction. We show that this finding is driven by a specification that demands more than simple convergence in poverty headcount rates and assumes a growth elasticity of poverty reduction, which is well-k...

  2. Finite element simulation of Reference Point Indentation on bone.

    Science.gov (United States)

    Idkaidek, Ashraf; Agarwal, Vineet; Jasiuk, Iwona

    2017-01-01

    Reference Point Indentation (RPI) is a novel technique aimed to assess bone quality. Measurements are recorded by the BioDent instrument that applies multiple indents to the same location of cortical bone. Ten RPI parameters are obtained from the resulting force-displacement curves. Using the commercial finite element analysis software Abaqus, we assess the significance of the RPI parameters. We create an axisymmetric model and employ an isotropic viscoelastic-plastic constitutive relation with damage to simulate indentations on a human cortical bone. Fracture of bone tissue is not simulated for simplicity. The RPI outputs are computed for different simulated test cases and then compared with experimental results, measured using the BioDent, found in literature. The number of cycles, maximum indentation load, indenter tip radius, and the mechanical properties of bone: Young׳s modulus, compressive yield stress, and viscosity and damage constants, are varied. The trends in the RPI parameters are then investigated. We find that the RPI parameters are sensitive to the mechanical properties of bone. An increase in Young׳s modulus of bone causes the force-displacement loading and unloading slopes to increase and the total indentation distance (TID) to decrease. The compressive yield stress is inversely proportional to a creep indentation distance (CID1) and the TID. The viscosity constant is proportional to the CID1 and an average of the energy dissipated (AvED). The maximum indentation load is proportional to the TID, CID1, loading and unloading slopes, and AvED. The damage parameter is proportional to the TID, but it is inversely proportional to both the loading and unloading slopes and the AvED. The value of an indenter tip radius is proportional to the CID1 and inversely proportional to the TID. The number of load cycles is inversely proportional to an average of a creep indentation depth (AvCID) and the AvED. The indentation distance increase (IDI) is strongly

  3. Influence of the indenter tip defect in classical indentation: Application to the hardness determination of DLC thin films

    Energy Technology Data Exchange (ETDEWEB)

    Benarioua, Y. [Département de Génie Mécanique, Faculté de Technologies, Université de M' Sila, BP 166, M’Sila 28000 (Algeria); Roudet, F. [Univ. Lille, FRE 3723-LML – Laboratoire de Mécanique de Lille, F-59000 Lille (France); Chicot, D., E-mail: didier.chicot@univ-lille1.fr [Univ. Lille, FRE 3723-LML – Laboratoire de Mécanique de Lille, F-59000 Lille (France)

    2016-04-26

    For an accurate determination of the materials hardness, instrumented indentation test is undoubtedly the most adequate technique compared to the classical one. However, numerous laboratories or industries have no access to such instrumented device. Consequently, they have no other alternative methods that the use of classical indentation test. However, this technique can lead to wrong interpretation because it does not allow considering the indenter tip defect. In this paper, we suggest to introduce the indenter tip defect into the classical hardness calculation. The proposed methodology is validated on a diamond like-carbon thin film deposited onto a tungsten carbide. Firstly, the truncated indenter tip defect length is estimated from the indentation size effect observed for the substrates which is attributed to the influence of the indenter tip defect. As a result, the tip defect is found to have the same value independently of the tested samples. Afterwards, the tip defect length is introduced into the composite hardness computation and the model of Jönsson and Hogmark is applied to predict film hardness. As a main result, the film hardness is found equal to 37.3 GPa independently of the film thickness and in a good accordance with literature data regarding the diamond hybridization sp3/sp2 ratio.

  4. poverty and poverty alleviation in globalised cities

    OpenAIRE

    Verena Ast

    2014-01-01

    In the light of increasing "division of the cities" and its underlying process of socio-spatial segregation researches focus more and more on the consequences of this process: the development of advantaged and disadvantaged districts within contemporary cities. Thereby especially poverty alleviation respectively poverty eradication in disadvantaged districts becomes an emerging and central field of intervention in social policies. This is due to the broad impact of poverty like higher risk of...

  5. Boron cycling in subduction zones

    OpenAIRE

    Palmer, Martin R.

    2017-01-01

    Subduction zones are geologically dramatic features, with much of the drama being driven by the movement of water. The “light and lively” nature of boron, coupled with its wide variations in isotopic composition shown by the different geo-players in this drama, make it an ideal tracer for the role and movement of water during subduction. The utility of boron ranges from monitoring how the fluids that are expelled from the accretionary prism influence seawater chemistry, to the subduction of c...

  6. Indentation and needle insertion properties of the human eye.

    Science.gov (United States)

    Matthews, A; Hutnik, C; Hill, K; Newson, T; Chan, T; Campbell, G

    2014-07-01

    Characterization of the biomechanical properties of the human eye has a number of potential utilities. One novel purpose is to provide the basis for development of suitable tissue-mimicking material. The purpose of this study was to determine the indentation and needle insertion characteristics on human eye globes and tissue strips. An indenter assessed the elastic response of human eye globes and tissue strips under increasing compressive loads. Needle insertion determined the force (N) needed to penetrate various areas of the eye wall. The results demonstrated that globes underwent slightly greater indentation at the midline than at the central cornea, and corneal strips indented twofold more than scleral strips, although neither difference was significant (P=0.400 and P=0.100, respectively). Significant differences were observed among various areas of needle insertion (Phuman eye construct with potential utility as a model for use in ophthalmology research and surgical teaching.

  7. Non-destructive test of steel structures by conical indentation

    Directory of Open Access Journals (Sweden)

    Beskopylny Alexey

    2017-01-01

    Full Text Available The problem of mechanical properties measurement of steel structures by non-destructive method of impact cone indentation is considered. The method is based on analytical solution and experimental data of a problem of impact indentation by cone into elastic-plastic half-space. Non-destructive dynamic indentation method is one of more efficient for mechanical properties assessment because of compact instrument that makes it possible of measuring at any point of structure. The scheme of impact indentation was considered and the problem of elastic-plastic impact is solved. The device with a computer way of information processing was created and tested for determining the characteristics of the existing structures. The method was adopted and tested on bridge structures, butt welded joints, civil engineering structures and others.

  8. Effect of viscoplastic material parameters on polymer indentation

    DEFF Research Database (Denmark)

    Tvergaard, V; Needleman, A

    2012-01-01

    The effect of material parameters characterizing viscoplastic flow on the indentation response of polymers is investigated using three-dimensional finite element analyses and a one-dimensional expanding spherical cavity model. The polymer is characterized by a finite strain elastic...... variations considered, it is found that two material stress parameters characterizing the plastic flow resistance have the largest effect on the value of the indentation hardness although variations in other material parameters can lead to significant variations....

  9. Evaluation for rheological constitutive relations, using the indentation technique

    Science.gov (United States)

    Fang, Lei

    1992-01-01

    A simple experimental method of determining the rheological constitutive relations is proposed. The method relies upon an analysis of the frictionless contact of a rigid spherical indenter and the rheological materials. The proposal addresses problems in two fields: rheological constitutive models and contact mechanics. It attempts to evaluate the rheological constitutive relations using an indentation technique. A systematic, optimization-based material parameter/function indentation model is proposed. The identification algorithm is based on a modified Marquardt-Levenberg method. A new integral constitutive equation for viscoelastic materials is derived. The derivation is carried out so that a damage function is included in the model in a relatively convenient form. Inclusion of damage effects makes this constitutive equation considerably more general than the widely accepted K-BKZ integral model. The single-step and double-step stress relaxation indentation experiments on asphalt materials were performed. The K-BKZ, Wagner, and nonlinear Volterra models were evaluated. It is demonstrated that the new integral constitutive model shows a very good agreement with the experimental data. The idea of damage function is introduced not only to have a better fit of data, but the damage (or irreversibility) is observed experimentally. Also, the creep indentation tests on composites were presented. A multiaxial theory of creep deformation for particle-strengthened metal matrix composites (Zhu-Weng Theory) was evaluated. The goal of the proposed research is to develop the indentation technique for use in basic mechanical studies. From the indentation test, material response is measured. The data are used in conjunction with the material parameter identification model to optimally back calculate the constitutive relations. indentation test and other experiment method demonstrates the viability of the proposed approach.

  10. Elastic layer under axisymmetric indentation and surface energy effects

    Science.gov (United States)

    Intarit, Pong-in; Senjuntichai, Teerapong; Rungamornrat, Jaroon

    2018-04-01

    In this paper, a continuum-based approach is adopted to investigate the contact problem of an elastic layer with finite thickness and rigid base subjected to axisymmetric indentation with the consideration of surface energy effects. A complete Gurtin-Murdoch surface elasticity is employed to consider the influence of surface stresses. The indentation problem of a rigid frictionless punch with arbitrary axisymmetric profiles is formulated by employing the displacement Green's functions, derived with the aid of Hankel integral transform technique. The problem is solved by assuming the contact pressure distribution in terms of a linear combination of admissible functions and undetermined coefficients. Those coefficients are then obtained by employing a collocation technique and an efficient numerical quadrature scheme. The accuracy of proposed solution technique is verified by comparing with existing solutions for rigid indentation on an elastic half-space. Selected numerical results for the indenters with flat-ended cylindrical and paraboloidal punch profiles are presented to portray the influence of surface energy effects on elastic fields of the finite layer. It is found that the presence of surface stresses renders the layer stiffer, and the size-dependent behavior of elastic fields is observed in the present solutions. In addition, the surface energy effects become more pronounced with smaller contact area; thus, the influence of surface energy cannot be ignored in the analysis of indentation problem especially when the indenter size is very small such as in the case of nanoindentation.

  11. Metallogeny of subduction zones

    Directory of Open Access Journals (Sweden)

    Sorokhtin N. O.

    2017-03-01

    Full Text Available The paper deals with the multistage mechanism of the Earth's crust enrichment in ore elements in underthrust zones. The processes of metamorphism and the formation of hydrothermal solutions at pulling of the watered oceanic lithospheric plate into the subduction zone have been described. Some physical and chemical transformation regularities of structural-material complexes in these areas and mechanisms of the formation of ore deposits have been discussed. Spatio-temporal patterns of the localization of a number of endogenetic and exogenetic deposits have been described using metallogeny of the Ural and the Verkhoyansk-Kolyma Fold Belts as an example. It has been shown that in nature there are several effective mechanisms of the enrichment of the crust in ore minerals. One of them is the process of pulling into subduction zone of metalliferous sediments and ferromanganese crusts as well as seabed nodules, their metamorphic transformation, partial melting and transition of ore components into magmatic melts and mineralized fluids. In the future this leads to the release of ore material by magmas and hydrothermal solutions into the folded formations of island-arc and Andean types and the formation of igneous, metasomatic and hydrothermal deposits. Another, yet no less powerful natural mechanism of a conveyor enrichment of the crust in ore elements is the process of destruction and sedimentation of mineral deposits formed in the folded areas as well as the formation of placers and their transfer to the marginal parts of the continent. Later, during the collision of active and passive margins of two lithospheric plates, such as the collision of the Kolyma Massif with the eastern part of the Siberian craton in the middle of the Mesozoic there was a thrusting of a younger lithospheric plate over a more ancient one. As a result, the sedimentary sequences of the passive margin of the Siberian plate were submerged and partially melted by the basic magmas

  12. Quasi-static indentation modelling of aluminium specimen using finite element analysis

    OpenAIRE

    Mayank Nirbhay; Mahima Dua; Anurag Dixit; Satpal Sharma; R.K. Misra

    2017-01-01

    The influence of different types of rigid hemispherical and conical indenters on a rectangular specimen of aluminium has been investigated, in the small indenter test. A 3-D finite-element FE model was used to carry out the computation of the elastic-plastic solution of different rigid hemispherical and conical indenters. Three hemispherical-headed and four conical-headed indenters were designed and developed for testing. FE software ABAQUS® has been used to determine the load vs. indenter-di...

  13. Child poverty and changes in child poverty.

    Science.gov (United States)

    Chen, Wen-Hao; Corak, Miles

    2008-08-01

    This article offers a cross-country overview of child poverty, changes in child poverty, and the impact of public policy in North America and Europe. Levels and changes in child poverty rates in 12 Organisation for Economic Co-operation and Development (OECD) countries during the 1990s are documented using data from the Luxembourg Income Study project, and a decomposition analysis is used to uncover the relative role of demographic factors, labor markets, and income transfers from the state in determining the magnitude and direction of the changes. Child poverty rates fell noticeably in only three countries and rose in three others. In no country were demographic factors a force for higher child poverty rates, but these factors were also limited in their ability to cushion children from adverse shocks originating in the labor market or the government sector. Increases in the labor market engagement of mothers consistently lowered child poverty rates, while decreases in the employment rates and earnings of fathers were a force for higher rates. Finally, there is no single road to lower child poverty rates. Reforms to income transfers intended to increase labor supply may or may not end up lowering the child poverty rate.

  14. Individualization of poverty?

    DEFF Research Database (Denmark)

    Bak, Carsten Kronborg

    2015-01-01

    that Beck’s thesis about the individualization and democratization of poverty is based on narrow income based definitions and that (possible) empirical verification depends on the definitions of poverty and approaches used to examine poverty. My analyses show that the dynamic perspective (using income...

  15. Adolescents and Poverty

    Science.gov (United States)

    Wight, Vanessa R.

    2011-01-01

    More youth live in poverty and poor youth comprise a larger share of the youth population than was the case a decade ago. This article first provides a descriptive analysis of children in poverty; examining the incidence of poverty among children by selected demographic, socioeconomic, and geographic characteristics with a particular focus on…

  16. Poverty in Education

    Science.gov (United States)

    Greever, Sadie

    2014-01-01

    The purpose of this literature review is to provide a comprehensive summary of the topic of poverty and its effects upon student behavior and academic performance. Presented in this chapter of the review of the related literature will be: (a) description of poverty and the role of education, (b) effects of poverty on student behavior, (c) effects…

  17. Poverty Monitor 1998

    NARCIS (Netherlands)

    1998-01-01

    Original title: Armoedemonitor 1998. The Poverty Monitor 1998 (Armoedemonitor 1998) presents a complete and up-to-date picture of poverty in the Netherlands. It is intended to provide a factual basis for the current debate on poverty. The Netherlands Institute for Social Research/SCP and

  18. Poverty Monitor 1999

    NARCIS (Netherlands)

    1999-01-01

    Original title: Armoedemonitor 1999. The Poverty Monitor 1999 (Armoedemonitor 1999) presents as complete and up-to-date a picture as possible of poverty in the Netherlands, and thus provides a factual basis for the debate on poverty. The Netherlands Institute for Social Research/SCP

  19. Congested subduction in New Zealand driving plate boundary reogranisation and accretion

    Science.gov (United States)

    Willis, D.; Betts, P. G.; Moresi, L. N.; Ailleres, L.

    2017-12-01

    Oblique dextral convergence along the Australia-Pacific plate boundary in the SW Pacific is characterised by large scale changes in the lithospheric composition of the convergent plates. Unimpeded subduction along the Tonga-Kermadec Trench transitions to subduction that is congested by the Hikurangi Plateau along the Hikurangi Trench and then to micro-continent collision along the Alpine Fault. The Marlborough Fault Zone is located at the edge of the Campbell Micro-continent, providing the structural link between the congested Hikurangi Trench and Alpine Fault. The Marlborough Fault Zone displays a 120 km step-wise migration of the plate boundary since the mid-Miocene, resulting in 700,000 km3 of crust accreting from the Pacific to the Australian Plate. To understand how congested subduction along the Pacific-Australia Plate Boundary influences plate boundary re-organisation and accretion in the Marlborough Fault Zone, we present 3D numerical models to understand the influence of lithospheric heterogeneity on the evolution of plate boundary geometry and deformation. We compare this with present day plate boundary deformation characterised by GPS and earthquake focal mechanisms. Paleo-stress analysis from striation data shows a clockwise P-axis rotation from 66° to 118° since the Mid-Miocene, indicating plate boundary rotations of at least 52°. This rotation is driven by collision of the Hikurangi Plateau with the Hikurangi Trench during the indentation of the Campbell micro-continent. The rotation of plate boundary acts to minimise the width of the colliding Hikurangi Plateau, and allows the plate boundary to unlock southward. We interpret the indentation of the Campbell micro-continent and southward unlocking of the Hikurangi Megathrust to drive the southward migration of the plate boundary in the Marlborough Fault Zone, and in doing so have identified a previously undescribed mechanism of accretion, which we term "Subduction propagation accretion".

  20. Explaining Poverty Evolution

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Mohammad Azhar; Jones, Edward Samuel

    Measuring poverty remains a complex and contentious issue. This is particularly true in sub-Saharan Africa where poverty rates are higher, information bases typically weaker, and the underlying determinants of welfare relatively volatile. This paper employs recently collected data on household...... the poverty-growth-inequality triangle. Finally, various simple but useful and rarely applied approaches to considering regional changes in poverty rates are presented. We find that the national poverty rate in Mozambique stagnated between 2002/03 and 2008/09....

  1. Poverty in Denmark

    DEFF Research Database (Denmark)

    Christensen, Anders Bøggild

    Recently poverty has become an issue in Danish public debates and research after some quiet years with not much attention. The intention with this paper is to make a descriptive covering view of the Danish research on poverty since the year of 2000 until summer 2009. We see quite some...... differentiation in the methods, measurement and results though most accept the concept of relative poverty (see for instance Peter Townsend 2006). We see qualitative and quantitative studies; studies based on the median income, studies based on poverty lines from minimum budget definitions and surveys including...... questions on deprivation etc.. This paper will present all major studies of empirical poverty research and discuss strengths and inadequacies in the research of poverty and finally raise some perspectives from the current political and professional debates which question poverty research....

  2. Finite element analysis of the cyclic indentation of bilayer enamel

    Science.gov (United States)

    Jia, Yunfei; Xuan, Fu-zhen; Chen, Xiaoping; Yang, Fuqian

    2014-04-01

    Tooth enamel is often subjected to repeated contact and often experiences contact deformation in daily life. The mechanical strength of the enamel determines the biofunctionality of the tooth. Considering the variation of the rod arrangement in outer and inner enamel, we approximate enamel as a bilayer structure and perform finite element analysis of the cyclic indentation of the bilayer structure, to mimic the repeated contact of enamel during mastication. The dynamic deformation behaviour of both the inner enamel and the bilayer enamel is examined. The material parameters of the inner and outer enamel used in the analysis are obtained by fitting the finite element results with the experimental nanoindentation results. The penetration depth per cycle at the quasi-steady state is used to describe the depth propagation speed, which exhibits a two-stage power-law dependence on the maximum indentation load and the amplitude of the cyclic load, respectively. The continuous penetration of the indenter reflects the propagation of the plastic zone during cyclic indentation, which is related to the energy dissipation. The outer enamel serves as a protective layer due to its great resistance to contact deformation in comparison to the inner enamel. The larger equivalent plastic strain and lower stresses in the inner enamel during cyclic indentation, as calculated from the finite element analysis, indicate better crack/fracture resistance of the inner enamel.

  3. Spherical Indentation Techniques for Creep Property Evaluation Considering Transient Creep

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Dongkyu; Kim, Minsoo; Lee, Hyungyil [Sogang Univ., Seoul, (Korea, Republic of); Lee, Jin Haeng [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-11-15

    Creep through nanoindentations has attracted increasing research attention in recent years. Many studies related to indentation creep tests, however, have simply focused on the characteristics of steady-state creep, and there exist wide discrepancies between the uniaxial test and the indentation test. In this study, we performed a computational simulation of spherical indentations, and we proposed a method for evaluating the creep properties onsidering transient creep. We investigated the material behavior with variation of creep properties and expressed it using regression equations for normalized variables. We finally developed a program to evaluate the creep properties considering transient creep. By using the proposed method, we successfully obtained creep exponents with an average error less than 1.1 and creep coefficients with an average error less than 2.3 from the load-depth curve.

  4. Spherical Indentation Techniques for Creep Property Evaluation Considering Transient Creep

    International Nuclear Information System (INIS)

    Lim, Dongkyu; Kim, Minsoo; Lee, Hyungyil; Lee, Jin Haeng

    2013-01-01

    Creep through nanoindentations has attracted increasing research attention in recent years. Many studies related to indentation creep tests, however, have simply focused on the characteristics of steady-state creep, and there exist wide discrepancies between the uniaxial test and the indentation test. In this study, we performed a computational simulation of spherical indentations, and we proposed a method for evaluating the creep properties onsidering transient creep. We investigated the material behavior with variation of creep properties and expressed it using regression equations for normalized variables. We finally developed a program to evaluate the creep properties considering transient creep. By using the proposed method, we successfully obtained creep exponents with an average error less than 1.1 and creep coefficients with an average error less than 2.3 from the load-depth curve

  5. Master-slave robotic system for needle indentation and insertion.

    Science.gov (United States)

    Shin, Jaehyun; Zhong, Yongmin; Gu, Chengfan

    2017-12-01

    Bilateral control of a master-slave robotic system is a challenging issue in robotic-assisted minimally invasive surgery. It requires the knowledge on contact interaction between a surgical (slave) robot and soft tissues. This paper presents a master-slave robotic system for needle indentation and insertion. This master-slave robotic system is able to characterize the contact interaction between the robotic needle and soft tissues. A bilateral controller is implemented using a linear motor for robotic needle indentation and insertion. A new nonlinear state observer is developed to online monitor the contact interaction with soft tissues. Experimental results demonstrate the efficacy of the proposed master-slave robotic system for robotic needle indentation and needle insertion.

  6. Disturbance induced by surface preparation on instrumented indentation test

    International Nuclear Information System (INIS)

    Li, Yugang; Kanouté, Pascale; François, Manuel

    2015-01-01

    Surface preparation, which may induce considerable sample disturbance, plays an important role in instrumented indentation test (IIT). In this study, the sample disturbance (mainly divided into residual stresses and plastic strain) induced by the surface preparation process of instrumented indentation test specimens were investigated with both experimental tests and numerical simulations. Grazing incidence X-ray diffractions (GIXRD) and uniaxial tensile tests were conducted for characterizing the residual stresses and high plastic strain in the top surface layers of a carefully mechanically polished indentation sample, which, in the present work, is made of commercially pure titanium. Instrumented indentation tests and the corresponding finite element simulations were performed as well. For comparison, a reference sample (carefully mechanically polished & electrolytically polished) which represents the raw material was prepared and tested. Results showed that a careful mechanical polishing procedure can effectively reduce the level of residual stresses induced by this process. However, the high plastic strain in the surface region imposed by the polishing process is significant. The induced plastic strain can affect a depth up to 5 µm, which is deeper than the maximum penetration depth h max (3 µm) used for the instrumented indentation tests. In the near surface layer (in the range of depth about 350 nm), the plastic strain levels are fairly high. In the very top layer, the plastic strain was even estimated to reach more than 60%. The simultaneous use of indentation tests and numerical simulations showed that the existence of high plastic strain in the surface region will make the load vs depth (P–h) curve shift upwards, the contact hardness (H) increase and the contact stiffness (S) decrease

  7. Poverty Relief or Poverty Eradication? | Kritzinger | Acta Theologica

    African Journals Online (AJOL)

    The author challenges the reader to make two mindshifts: from a focus on poverty relief to an emphasis on poverty eradication; and from viewing the poor as the objects of poverty alleviation to accepting them as the subjects of poverty eradication. The case is argued and a practical approach towards poverty eradication is ...

  8. International Comparisons of Income Poverty and Extreme Income Poverty

    OpenAIRE

    Blackburn, McKinley L.

    1993-01-01

    Uses LIS data to study the sensitivity of cross-national income poverty comparisons to the method in which poverty is measured. Examined are the differences between using absolute and relative poverty comparisons as well as the consequence of lowering the real value of the poverty line to examine extreme poverty.

  9. Poverty in Edwardian Britain.

    Science.gov (United States)

    Gazeley, Ian; Newell, Andrew

    2011-01-01

    This article introduces a newly discovered household budget data set for 1904. We use these data to estimate urban poverty among working families in the British Isles. Applying Bowley's poverty line, we estimate that at least 23 per cent of people in urban working households and 18 per cent of working households had income insufficient to meet minimum needs. This is well above Rowntree's estimate of primary poverty for York in 1899 and high in the range that Bowley found in northern towns in 1912–13. The skill gradient of poverty is steep; for instance, among labourers' households, the poverty rates are close to 50 per cent. Measures of the depth of poverty are relatively low in the data, suggesting that most poor male-headed working households were close to meeting Bowley's new standard.

  10. Processes and consequences of deep subduction

    NARCIS (Netherlands)

    Rubie, David C.; Hilst, R.D. van der

    2001-01-01

    Subduction of slabs of oceanic lithosphere into the deep mantle involves a wide range of geophysical and geochemical processes and is of major importance for the physical and chemical evolution of the Earth. For example, subduction and subduction-related volcanism are major processes through

  11. ECONOMIC GROWTH AND POVERTY,

    Science.gov (United States)

    The problems of poverty in the United States, and their resolution, are inextricably connected with the nature of the economic growth process and its...economic deprivation, but the adjustments required by growth have left in their wake new pockets of poverty . In the future, one of the key variables...that will determine how rapidly we can eliminate poverty in the United States will be the rate of increase in average incomes. And one of the key

  12. Seismology: A giant subducting sausage

    Science.gov (United States)

    Warren, Linda M.

    2008-03-01

    Earthquake data seem to reveal a huge sausage-shaped slab of material detaching itself from the material subducting as two plates meet beneath the Hindu Kush. This largest-ever 'boudin' could tell us more about what happens when continents collide.

  13. Application of Indenting Method for Calculation of Activation Energy

    International Nuclear Information System (INIS)

    Kim, Jong-Seog; Kim, Tae-Ryong

    2006-01-01

    For the calculation of activation energy of cable materials, we used to apply the break-elongation test in accordance with ASTM D412(Stand Test Methods for Rubber Properties in Tension). For the cable jacket and insulation which have regular thickness, break-elongation test had been preferred since it showed linear character in the activation energy curve. But, for the cable which has irregular thickness or rugged surface of cable inside, break-elongation test show scattered data which can not be used for the calculation of activation energy. It is not easy to prepare break-elongation specimen for the cable smaller than 13mm diameter in accordance with ASTM D412. In the cases of above, we sometime use TGA method which heat the specimen from 50 .deg. C to 700 .deg. C at heating rates of 10, 15, 20 .deg. C/min. But, TGA is suspected for the representative of natural aging in the plant since it measure the weight decreasing rate during burning which may have different aging mechanism with that of natural aging. To solve above problems, we investigated alternatives such as indenter test. Indenter test is very convenient since it does not ask for a special test specimen as the break-elongation test does. Regular surface of cable outside is the only requirement of indenter test. Experience of activation energy calculation by using the indenter test is described herein

  14. Rigid indented cylindrical cathode for X-ray tube

    Science.gov (United States)

    Hudgens, Claude R.

    1985-01-01

    A cathode assembly for a vacuum tube includes a wire filament, a straight bular anode parallel to and surrounding the wire filament, and insulating spacers for rigidly fastening the filament with respect to the anode, and with one side of the anode indented or flattened such that only one portion of the anode is heated to emitting temperatures by the filament.

  15. Image analysis of moving seeds in an indented cylinder

    DEFF Research Database (Denmark)

    Buus, Ole; Jørgensen, Johannes Ravn

    2010-01-01

    inspection in seed cleaning equipment. A prototype of an indented cylinder will be constructed. To make it more dynamic, the cylinder itself will be manufactured using 3D printing technology. The input will come either from 3D scans of existing cylinders or by defining their topology using parametric B...

  16. Indentation fatigue in silicon nitride, alumina and silicon carbide ...

    Indian Academy of Sciences (India)

    Unknown

    ceramics viz. a hot pressed silicon nitride (HPSN), sintered alumina of two different grain sizes viz. 1 µm and. 25 µm, and a sintered silicon ... the sintered silicon carbide was found out to be linked to its previous thermal history. Keywords. Indentation fatigue .... This presence of a grain size effect in the RIF behaviour of the ...

  17. Hardness and elasticity of abrasive particles measured by instrumented indentation

    Czech Academy of Sciences Publication Activity Database

    Hvizdoš, P.; Zeleňák, Michal; Hloch, Sergej

    2016-01-01

    Roč. 8, č. 1 (2016), s. 869-871 ISSN 1805-0476 Institutional support: RVO:68145535 Keywords : abrasive * garnet * hardness * elasticity * instrumental indentation Subject RIV: JQ - Machines ; Tools http://www.mmscience.eu/content/file/archives/MM_Science_201601.pdf

  18. Buckling of Single-Crystal Silicon Nanolines under Indentation

    Directory of Open Access Journals (Sweden)

    Min K. Kang

    2008-01-01

    Full Text Available Atomic force microscope-(AFM- based indentation tests were performed to examine mechanical properties of parallel single-crystal silicon nanolines (SiNLs of sub-100-nm line width, fabricated by a process combining electron-beam lithography and anisotropic wet etching. The SiNLs have straight and nearly atomically flat sidewalls, and the cross section is almost perfectly rectangular with uniform width and height along the longitudinal direction. The measured load-displacement curves from the indentation tests show an instability with large displacement bursts at a critical load ranging from 480 μN to 700 μN. This phenomenon is attributed to a transition of the buckling mode of the SiNLs under indentation. Using a set of finite element models with postbuckling analyses, we analyze the indentation-induced buckling modes and investigate the effects of tip location, contact friction, and substrate deformation on the critical load of mode transition. The results demonstrate a unique approach for the study of nanomaterials and patterned nanostructures via a combination of experiments and modeling.

  19. Prediction of Indentation Behavior of Superelastic TiNi

    Science.gov (United States)

    Neupane, Rabin; Farhat, Zoheir

    2014-09-01

    Superelastic TiNi shape memory alloys have been extensively used in various applications. The great interest in TiNi alloys is due to its unique shape memory and superelastic effects, along with its superior wear and dent resistance. Assessment of mechanical properties and dent resistance of superelastic TiNi is commonly performed using indentation techniques. However, the coupling of deformation and reversible martensitic transformation of TiNi under indentation conditions makes the interpretation of results challenging. An attempt is made to enhance current interpretation of indentation data. A load-depth curve is predicted that takes into consideration the reversible martensitic transformation. The predicted curve is in good agreement with experimental results. It is found in this study that the elastic modulus is a function of indentation depth. At shallow depths, the elastic modulus is high due to austenite dominance, while at high depths, the elastic modulus drops as the depth increases due to austenite to martensite transition, i.e., martensite dominance. It is also found that TiNi exhibits superior dent resistance compared to AISI 304 steel. There is two orders of magnitude improvement in dent resistance of TiNi in comparison to AISI 304 steel.

  20. Indentation fatigue in silicon nitride, alumina and silicon carbide ...

    Indian Academy of Sciences (India)

    Repeated indentation fatigue (RIF) experiments conducted on the same spot of different structural ceramics viz. a hot pressed silicon nitride (HPSN), sintered alumina of two different grain sizes viz. 1 m and 25 m, and a sintered silicon carbide (SSiC) are reported. The RIF experiments were conducted using a Vicker's ...

  1. Competing indentation deformation mechanisms in glass using different strengthening methods

    Directory of Open Access Journals (Sweden)

    Jian Luo

    2016-11-01

    Full Text Available Chemical strengthening via ion exchange, thermal tempering, and lamination are proven techniques for strengthening of oxide glasses. For each of these techniques, the strengthening mechanism is conventionally ascribed to the linear superposition of the compressive stress profile on the glass surface. However, in this work we use molecular dynamics simulations to reveal the underlying indentation deformation mechanism beyond the simple linear superposition of compressive and indentation stresses. In particular, the plastic zone can be dramatically different from the commonly assumed hemispherical shape, which leads to a completely different stress field and resulting crack system. We show that the indentation-induced fracture is controlled by two competing mechanisms: the compressive stress itself and a potential reduction in free volume that can increase the driving force for crack formation. Chemical strengthening via ion exchange tends to escalate the competition between these two effects, while thermal tempering tends to reduce it. Lamination of glasses with differential thermal expansion falls in between. The crack system also depends on the indenter geometry and the loading stage, i.e., loading vs. after unloading. It is observed that combining thermal tempering or high free volume content with ion exchange or lamination can impart a relatively high compressive stress and reduce the driving force for crack formation. Therefore, such a combined approach might offer the best overall crack resistance for oxide glasses.

  2. Poverty comparisons with absolute poverty lines estimated from survey data

    OpenAIRE

    Simler. Kenneth R.; Arndt, Channing

    2006-01-01

    "The objective of measuring poverty is usually to make comparisons over time or between two or more groups. Common statistical inference methods are used to determine whether an apparent difference in measured poverty is statistically significant. Studies of relative poverty have long recognized that when the poverty line is calculated from sample survey data, both the variance of the poverty line and the variance of the welfare metric contribute to the variance of the poverty estimate. In co...

  3. Application of the method of dimensionality reduction to simulate the fretting wear of anisotropic indenter

    Science.gov (United States)

    Dmitriev, A. I.

    2015-10-01

    In the paper we consider the fretting wear of two contacting bodies (indenter and half-space). Due to heterogeneity the indenter in contact area can have different mechanical properties. With an increasing number of cycles, the wear profile tends towards a limiting shape, in which no further wear occurs. Nonlinear dependence between final wear volume and indenter shear modulus was found. In accordance with our results the soft indenter provides less wear volume under fretting wear.

  4. Poverty Mapping Project: Small Area Estimates of Poverty and Inequality

    Data.gov (United States)

    National Aeronautics and Space Administration — The Small Area Estimates of Poverty and Inequality dataset consists of consumption-based poverty, inequality and related measures for subnational administrative...

  5. Residual stress estimation of ceramic thin films by X-ray diffraction and indentation techniques

    International Nuclear Information System (INIS)

    Atar, Erdem; Sarioglu, Cevat; Demirler, Ugur; Sabri Kayali, E.; Cimenoglu, Huseyin

    2003-01-01

    The residual stresses in ceramic thin films obtained by the indentation method have been found to be three times higher than those of the X-ray diffraction method. This discrepancy can be eliminated by setting the geometrical factor for the Vickers pyramid indenter to 1 in the relevant equation of the indentation method

  6. Rethinking Education and Poverty

    Science.gov (United States)

    Tierney, William G., Ed.

    2015-01-01

    In "Rethinking Education and Poverty," William G. Tierney brings together scholars from around the world to examine the complex relationship between poverty and education in the twenty first century. International in scope, this book assembles the best contemporary thinking about how education can mediate class and improve the lives of…

  7. Poverty and Education

    Science.gov (United States)

    Thomson, Pat

    2015-01-01

    In this article the author discusses the multiple ways in which the enduring, and increasing, problems associated with child poverty blight young people's educational opportunities in the school system. Current policies, supported by a sympathetic media, blame individuals for their poverty, and blame teachers when they fail to "close the…

  8. Poverty and Aspirations Failure

    NARCIS (Netherlands)

    Dalton, P.S.; Ghosal, S.; Mani, A.

    2011-01-01

    We develop a theoretical framework to study the psychology of poverty and 'aspirations failure'. In our framework, the rich and the poor share the same preferences - and also a behavioral bias in setting aspirations. Greater downside risks imposed by poverty exacerbates the effects of this

  9. Poverty and aspirations failure

    NARCIS (Netherlands)

    Dalton, P.S.; Ghosal, S.; Mani, A.

    We develop a theoretical framework to study the psychology of poverty and ‘aspirations failure’, defined as the failure to aspire to one’s own potential. In our framework, rich and the poor persons share the same preferences and same behavioral bias in setting aspirations. We show that poverty can

  10. Poverty monitor 2007

    NARCIS (Netherlands)

    Cok Vrooman; Stella Hoff; Ferdy Otten; Wim Bos

    2007-01-01

    Original title: Armoedemonitor 2007. The Poverty Monitor 2007 contains the most up-to-date figures on poverty in the Netherlands. The data were collected and analysed by the Netherlands Institute for Social Research/SCP in collaboration with Statistics Netherlands (CBS). The report describes

  11. Poverty Monitor 2000

    NARCIS (Netherlands)

    2000-01-01

    Original title: Armoedemonitor 2000. The Poverty Monitor 2000 (Armoedemonitor 2000) contains the most up-to-date figures on poverty in the Netherlands. The data were collected and analysed by the Netherlands Institute for Social Research/SCP and Statistics Netherlands (CBS). The extent of

  12. Poverty Monitor 2001

    NARCIS (Netherlands)

    2001-01-01

    Original title: Armoedemonitor 2001. The Poverty Monitor 2001 (Armoedemonitor 2001) contains the most up-to-date figures on poverty in the Netherlands. The data were collected and analysed by the Netherlands Institute for Social Research/SCP and Statistics Netherlands (CBS). The extent of and

  13. Fighting Poverty with Facts

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC's in_focus Collection tackles current and pressing issues in sustainable international development. .... Political commitment is key to sustainability. ...... It can also trace the evolution of poverty over time in a given community and at household levels, thereby providing insights into the dynamics of poverty transitions.

  14. Subjective poverty line definitions

    NARCIS (Netherlands)

    J. Flik; B.M.S. van Praag (Bernard)

    1991-01-01

    textabstractIn this paper we will deal with definitions of subjective poverty lines. To measure a poverty threshold value in terms of household income, which separates the poor from the non-poor, we take into account the opinions of all people in society. Three subjective methods will be discussed

  15. "Poverty and Household Composition"

    OpenAIRE

    Joan R. Rodgers

    1990-01-01

    This paper has investigated the relationship between poverty and family type, as reflected in the marital status and gender of the head of the family number of factors have been identified as important determinants of poverty for all family types: education and work experience of family members, race, disability, and unemployment of the family head, geographical location, size and composition of the family.

  16. Measuring Poverty in South Africa

    OpenAIRE

    Ingrid Woolard; Murray Leibbrandt

    1999-01-01

    This paper sets out the methodological issues for the measurement of poverty before presenting a poverty profile of South Africa. It tests the sensitivity of the poverty profile to choices around the metric used to measure well-being, the equivalence scale used and the level of the poverty line. The key finding is that the defining features of South African poverty are so pronounced that the profile of poverty is robust to changes in the underlying measurement assumptions. Gauteng, South Afri...

  17. Institutions and poverty.

    Science.gov (United States)

    Tebaldi, Edinaldo; Mohan, Ramesh

    2010-01-01

    This study utilises eight alternative measures of institutions and the instrumental variable method to examine the impacts of institutions on poverty. The estimates show that an economy with a robust system to control corruption, an effective government, and a stable political system will create the conditions to promote economic growth, minimise income distribution conflicts, and reduce poverty. Corruption, ineffective governments, and political instability will not only hurt income levels through market inefficiencies, but also escalate poverty incidence via increased income inequality. The results also imply that the quality of the regulatory system, rule of law, voice and accountability, and expropriation risk are inversely related to poverty but their effect on poverty is via average income rather than income distribution.

  18. Decisions in poverty contexts.

    Science.gov (United States)

    Shafir, Eldar

    2017-12-01

    The circumstances surrounding poverty-tight financial challenges, instability of income and expenses, low savings, no insurance, and several other stressors-translate into persistent and cognitively taxing hardship for people in poverty contexts. Thoughts about money and expenses loom large, shape mental associations, interfere with other experiences, and are difficult to suppress. The persistent juggling of insufficient resources affects attention, cognitive resources, and ensuing decisions. Despite the demanding struggle with challenging circumstances, people in poverty encounter disdain rather than admiration, and obstacles rather than support. Societal appreciation for the power of context, along with behaviorally informed programs designed to facilitate life under poverty, are essential for those in poverty contexts to be able to make the most of their challenging circumstances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Immigrant Child Poverty

    DEFF Research Database (Denmark)

    Galloway, Taryn Ann; Gustafsson, Björn; Pedersen, Peder J.

    2015-01-01

    of immigrant children from low- and middle-income countries when measured in yearly data is also found when applying a longer accounting period for poverty measurement. We find that child poverty rates are generally high shortly after arrival to the new country and typically decrease with years since......Immigrant and native child poverty in Denmark, Norway, and Sweden 1993–2001 is studied using large sets of panel data. While native children face yearly poverty risks of less than 10 percent in all three countries and for all years studied the increasing proportion of immigrant children...... with an origin in middle- and low-income countries have poverty risks that vary from 38 up to as much as 58 percent. At the end of the observation period, one third of the poor children in Norway and as high as about a half in Denmark and in Sweden are of immigrant origin. The strong overrepresentation...

  20. Matter and Poverty

    Directory of Open Access Journals (Sweden)

    María Teresa Muñoz

    2013-10-01

    Full Text Available AbstractAccumulation of matter is one of the most recognizable signs of poverty. The poor lives close to the earth, this is his only property and he will use it to build his shelters, his rooms, or his utensils. The clay or mud constructions, moulded with a great amount of material, are found in primitive villages, but any situation of extreme poverty tends to be associated with an accumulation of matter whatever its origin. A situation of poverty not related with the accumulation of matter seems inconceivable and this is particularly evident in our developed societies, where a beggar is recognized in any street by his pile of clothes, shoes, and any sort of personal property.It is a significant fact that many intellectual discourses on modernity identify the concept of modernity with that of a classless society and that, at the same time, they invoke poverty as a distinct mark of the new man. This new poverty is sober and cold as human habitation is open and transparent, almost naked, and it is equal for any man whatever his social strata. In this way, modern poverty is tied to material, to the new materials, but it is a chosen condition, nor an imposed one, or at least it is accepted as inevitable by the new man.Both accumulative poverty and ascetic poverty coexist in the discourses and works of 20th century avant-gardes. And in some contemporary works, we find either an accumulation of shapeless and hand-worked matter or an exhibition of bare and cold materials industrially produced. In both cases, poverty is invoked as the ultimate reference for those works, intended to be a true expression of their epoch.Key wordsmatter, poverty, material, accumulation, modernity, society

  1. Poverty Eradication Dilemma: Understanding Poverty Dynamics in ...

    African Journals Online (AJOL)

    The paper approaches this dilemma using a participatory and community-driven approach where the subjective views of people are used to define and categorize the poor, contrary to the poverty line approach. Such categorization was based on the perceived wellness of life and what made/denied wellness. A survey ...

  2. Influence of the molecular structure on indentation size effect in polymers

    International Nuclear Information System (INIS)

    Han, Chung-Souk

    2010-01-01

    Size dependent deformation of polymers has been observed by various researchers in various experimental settings including micro beam bending, foams and indentation testing. Here in this article the indentation size effect in polymers is examined which manifests itself in increased hardness at decreasing indentation depths. Based on previously suggested rationale of size dependent deformation and depth dependent hardness model the depth dependent hardness of various polymers are analyzed. It is found that polymers containing aromatic rings in their molecular structure exhibit depth dependent hardness above the micron length scale. For polymers not containing aromatic rings polymers the indentation size effect starts at smaller indentation depths if they are present at all.

  3. Analog Modeling of the Juan Fernández Ridge, Central Chile, and Implications for Flat-Slab Subduction Dynamics

    Science.gov (United States)

    Woodell, D.; Anderson, M. L.

    2009-12-01

    This study compares the strain experienced by the subducting lithosphere in analog models to the strain recorded by earthquakes in the subduction zone that includes the Juan Fernández Ridge (JFR), near 33 S, 73 W, off the coast of central Chile. The JFR is an aseismic hot spot ridge that has a thickened oceanic crust. The overthickened crust reduces the total density of the slab when compared to the surrounding slab areas, and thus increases the buoyancy of the subducting Nazca plate at this particular location. It is hypothesized that the Nazca plate experiences “flat-slab” subduction at the JFR subduction zone due to this buoyancy. Brudzinski and Chen (2005) argue that, due to the poorly aligned direction of maximum extension (T axes) for earthquakes in the subducting slab in flat-slab subduction zones, the theory of “slab pull” may not be valid for flat-slab subduction zones, and there must be other forces at work. However, Anderson et al. (2007) develop new, more precise slab contours from newly determined earthquake locations and use these contours to qualitatively compare the earthquake data to slab dip directions and thus expected slab-pull directions. They conclude that T axes are parallel to slab dip, and thus slab pull is the only force necessary for explaining the T axis direction. In this study, we quantitatively compare extension produced in analog "flat-slab" models in the laboratory to T axes from the Anderson et al. (2007) study, extending and further testing their idea. Several materials comprise the analog models. Light corn syrup represents the asthenosphere, while silicon putty represents the lithosphere. Recreating the dynamics of the buoyant JFR necessitates two different densities of silly putty: a denser one for the bulk of the slab, and a less dense one for the buoyant ridge. Shallow circular indentations (strain ellipses) on the slab facilitate recording of the strain in the subducting slab. Video and still pictures record each

  4. Metallography of the indented aluminium sheet fracture surfaces

    International Nuclear Information System (INIS)

    Khan, M.A.; Qaiser, S.; Haq, A.U.; Atkins, A.G.

    1997-01-01

    It was experimentally observed that indentation of aluminium sheet samples with a sharp tool leads the off cut metal into a flare out-curvature, whose shape depends upon the geometry of the tool, applied force, displacement, material properties etc. The crack initiation, crack propagation and fracture surfaces were studied. Type grain, fibers, cut marks and voids were analyzed on optical and scanning electron microscopes to see how these were produced,. and their relationship to the material inherent properties, since this phenomenon has hot been studied so far. The sharp tool angles were responsible for the plastic flow. Plastic work per volume, fracture toughness and deformation area of the indented material. The metallographic information provided details of sheet metal deformation, and failure into the particular shapes represented on the fracture surfaces. (author)

  5. Studi Komparasi Kemiskinan Di Indonesia: Multidimensional Poverty Dan Monetary Poverty

    OpenAIRE

    Nuryitmawan, Tegar Rismanuar

    2016-01-01

    Research on poverty has long been done by various methods and approaches. Approach to identifying the poor in general by calculating consumption expenditure or income reveneu. The calculation is then known as monetary poverty. Indonesia also use and implemented that approach. However, some experts believe that monetary poverty approach does not capture the whole cause of poverty because the indicator calculation not enough. Though poverty is a multidimensional phenomenon that involves not onl...

  6. STUDI KOMPARASI KEMISKINAN DI INDONESIA: MULTIDIMENSIONAL POVERTY DAN MONETARY POVERTY

    OpenAIRE

    Nuryitmawan, Tegar Rismanuar

    2016-01-01

    Research on poverty has long been done by various methods and approaches. Approach to identifying the poor in general by calculating consumption expenditure or income reveneu. The calculation is then known as monetary poverty. Indonesia also use and implemented that approach. However, some experts believe that monetary poverty approach does not capture the whole cause of poverty because the indicator calculation not enough. Though poverty is a multidimensional phenomenon that involves not onl...

  7. Full-Field Indentation Damage Measurement Using Digital Image Correlation

    Directory of Open Access Journals (Sweden)

    Elías López-Alba

    2017-07-01

    Full Text Available A novel approach based on full-field indentation measurements to characterize and quantify the effect of contact in thin plates is presented. The proposed method has been employed to evaluate the indentation damage generated in the presence of bending deformation, resulting from the contact between a thin plate and a rigid sphere. For this purpose, the 3D Digital Image Correlation (3D-DIC technique has been adopted to quantify the out of plane displacements at the back face of the plate. Tests were conducted using aluminum thin plates and a rigid bearing sphere to evaluate the influence of the thickness and the material behavior during contact. Information provided by the 3D-DIC technique has been employed to perform an indirect measurement of the contact area during the loading and unloading path of the test. A symmetrical distribution in the contact damage region due to the symmetry of the indenter was always observed. In the case of aluminum plates, the presence of a high level of plasticity caused shearing deformation as the load increased. Results show the full-field contact damage area for different plates’ thicknesses at different loads. The contact damage region was bigger when the thickness of the specimen increased, and therefore, bending deformation was reduced. With the proposed approach, the elastic recovery at the contact location was quantified during the unloading, as well as the remaining permanent indentation damage after releasing the load. Results show the information obtained by full-field measurements at the contact location during the test, which implies a substantial improvement compared with pointwise techniques.

  8. Characterization of Rubbers from Spherical Punch - Plate Indentation Tests

    Directory of Open Access Journals (Sweden)

    Florina Carmen Ciornei

    2016-12-01

    Full Text Available Rubber plates with different compositions and hardness were tested by continuous indentation, using a spherical punch and hysteretic phenomenon was evidenced. The experimental data interpolation with polynomial functions is accurate and permits estimation of the lost work during loading cycles. The interpolation by power law functions is more convenient by using less parameters and having a form accepted in literature. From the rubbers tested, two were considered to present good damping properties.

  9. Extraordinary Indentation Strain Stiffening Produces Superhard Tungsten Nitrides

    Science.gov (United States)

    Lu, Cheng; Li, Quan; Ma, Yanming; Chen, Changfeng

    2017-09-01

    Transition-metal light-element compounds are a class of designer materials tailored to be a new generation of superhard solids, but indentation strain softening has hitherto limited their intrinsic load-invariant hardness to well below the 40 GPa threshold commonly set for superhard materials. Here we report findings from first-principles calculations that two tungsten nitrides, hP4-WN and hP 6 -WN2 , exhibit extraordinary strain stiffening that produces remarkably enhanced indentation strengths exceeding 40 GPa, raising exciting prospects of realizing the long-sought nontraditional superhard solids. Calculations show that hP4-WN is metallic both at equilibrium and under indentation, marking it as the first known intrinsic superhard metal. An x-ray diffraction pattern analysis indicates the presence of hP4-WN in a recently synthesized specimen. We elucidate the intricate bonding and stress response mechanisms for the identified structural strengthening, and the insights may help advance rational design and discovery of additional novel superhard materials.

  10. Extrinsic stretching narrowing and anterior indentation of the rectosigmoid junction

    International Nuclear Information System (INIS)

    Schulman, A.; Fataar, S.

    1979-01-01

    Thirty-five cases of extrinsic narrowing or anterior indentation of the rectosigmoid junction (RSJ) have been studied. The RSJ lies directly behind the pouch of Douglas which is a favoured site for peritoneal metastasis, abscess and endometriosis. Any space-occupying lesion of sufficient size at this site will indent the anterior aspects of the RSJ. Causes include distension or tumour of the ileum or sigmoid colon, gross ascites (when the patient is erect), and tumours below the pelvic peritonium, such as gynaecological neoplasm and internal iliac artery aneurysm. When a desmoplastic metastasis in the pouch of Douglas infiltrates the outer layers of the RSJ, the fibrosis produces an eccentric shortening on its anterior aspect, which in turn causes a pleating of the mucosa with the folds radiating towards the shortened area. This is also seen with primary pelvic carcinomas directly adherent to the rectum, endometriosis with repeated bleeding and increasing eccentric, submucosal fibrosis, and chronic abscess in the pouch of Douglas. Not all extrinsic narrowing of the RSJ are pathological. One case of anterior indentation followed operation for rectal prolapse. Ten additional cases showed narrowing due to a technical artefact air-distended colon rising into the upper abdomen to cause stretching at the RSJ. As with ascites, this narrowing due to 'high-rise sigmoid' disappeared when the patients became recumbent and the colonic air redistributed. (author)

  11. Poverty and psychology

    NARCIS (Netherlands)

    Poluektova, Olga V.; Efremova, Maria V.; Breugelmans, S.M.

    2015-01-01

    This paper presents a study on the association between dimensions of poverty (income, subjective socioeconomic status, deprivation, and socioeconomic status in childhood) and individual psychological characteristics. In this study, our goal was to determine: 1) the differences in individual

  12. How we see poverty

    Directory of Open Access Journals (Sweden)

    Jonathan Morduch

    2012-06-01

    Full Text Available How we think about poverty is colored by how we measure it. For economists, that often means seeing poverty through quantities measured in large, representative surveys.  The surveys give a comprehensive view, but favor breadth over depth. Typical economic surveys are limited in their ability to tease out informal activity, and, while they capture yearly sums, they offer little about how the year was actually lived by families. Year-long financial diaries provide a complementary way of seeing poverty, with a focus on week by week choices and challenges. The result is a re-framing of poverty and its relationship to money, calling for greater attention to financial access and a broader notion of how finance matters.

  13. Growth and Poverty

    DEFF Research Database (Denmark)

    Arndt, Channing; Leyaro, Vincent; Mahrt, Kristi

    2017-01-01

    This chapter considers the evolution of welfare of the Tanzanian population using a multi-dimensional approach. It also employs a detailed economy-wide model of the Tanzanian economy to explore growth and monetary poverty reduction scenarios from 2007 to 2015. This approach permits assessment...... of the coherence of observed trends in macroeconomic variables and projects consumption poverty outcomes to 2015. In the multi-dimensional approach, we find that real gains have been achieved. On monetary poverty, our model broadly reproduces key macroeconomic features of the past eight years. We find...... that published consumption poverty reductions for 2007 to 2011/12 from the most recent assessment fall within a reasonable to optimistic range. And, the simulations generate broader based growth across the income distribution compared with the recent assessment. Looking forward, the simulations from 2012 to 2105...

  14. Analysis of Multidimensional Poverty

    International Development Research Centre (IDRC) Digital Library (Canada)

    unavailability of different services, infrastructures, etc.) trickle down to all households in the community. Endogenous transmission of poverty goes the other direction: a demographic unit is poor if some of his members are poor at their own level.

  15. Analysis of the equivalent indenter concept used to extract Young’s modulus from a nano-indentation test: some new insights into the Oliver–Pharr method

    DEFF Research Database (Denmark)

    Andriollo, Tito; Thorborg, Jesper; Hattel, Jesper Henri

    2017-01-01

    on an equivalent conical indenter whose semi-apical angle depends on the ratio between residual and total penetration. Specifically, this angle tends to 90° when the material exhibits extensive inelastic deformation, whereas it reduces to the one characteristic of the real indenter for a perfectly elastic material...

  16. Post-collisional deformation of the Anatolides and motion of the Arabian indenter: A paleomagnetic analysis

    International Nuclear Information System (INIS)

    Piper, J; Tatar, O; Gursoy, H; Mesci, B L; Kocbulut, F; Huang, B

    2008-01-01

    In the Anatolides of Turkey the neotectonic (post collisional) phase of deformation embraces the period since final closure of the southern arm of Neotethys in mid-Miocene times. The Arabian Shield indenter has continued to deform into the weak Anatolian accretionary collage resulting from subduction of this ocean by a combination of differential movement relative to the African Plate and counterclockwise (CCW) rotation. Much of resulting deformation has been accommodated by slip along major transforms comprising the North Anatolian Fault Zone (NAFZ), the East Anatolian Fault Zone (EAFZ) and the northward extension of the Dead Sea Fault Zone (DSFZ) but has also been distributed as differential block rotations through the zone of weak crust in between. Facets of this deformation comprise crustal thickening and uplift to produce the Anatolian Plateau, establishment of transform faults and tectonic escape as Arabia has continued to impinge into the Anatolian collage. Paleomagnetic analysis of this deformation is facilitated by the widespread distribution of neotectonic volcanism and graben infills, and rotations relative to the Eurasian reference frame are recognised on two scales. Rapid rotation (up to 5 0 /10,000 years) of small fault blocks is identified between master faults along the intracontinental transforms but deformation does not extend away from these zones and shows that seismogenic upper crust is decoupled from a lower continental lithosphere undergoing continuum deformation. The broad area of weak accreted crust between the transforms is dissected into large fault blocks which exhibit much lower rotation rates (mostly 0 /100,000 years) that vary systematically across the Anatolides. Large CCW rotations near the Arabian indenter diminish westwards to become zero then CW near the limit of tectonic escape in western Turkey. The view that the collage has rotated anticlockwise as a single plate, either uniformly or episodically, during the Neotectonic era is

  17. Assessment of the Local Residual Stresses of 7050-T7452 Aluminum Alloy in Microzones by the Instrumented Indentation with the Berkovich Indenter

    Science.gov (United States)

    He, M.; Huang, C. H.; Wang, X. X.; Yang, F.; Zhang, N.; Li, F. G.

    2017-10-01

    The local residual stresses in microzones are investigated by the instrumented indentation method with the Berkovich indenter. The parameters required for determination of residual stresses are obtained from indentation load-penetration depth curves constructed during instrumented indentation tests on flat square 7050-T7452 aluminum alloy specimens with a central hole containing the compressive residual stresses generated by the cold extrusion process. The force balance system with account of the tensile and compressive residual stresses is used to explain the phenomenon of different contact areas produced by the same indentation load. The effect of strain-hardening exponent on the residual stress is tuned-off by application of the representative stress σ_{0.033} in the average contact pressure assessment using the Π theorem, while the yield stress value is obtained from the constitutive function. Finally, the residual stresses are calculated according to the proposed equations of the force balance system, and their feasibility is corroborated by the XRD measurements.

  18. On the relationship between indentation hardness and modulus, and the damage resistance of biological materials.

    Science.gov (United States)

    Labonte, David; Lenz, Anne-Kristin; Oyen, Michelle L

    2017-07-15

    The remarkable mechanical performance of biological materials is based on intricate structure-function relationships. Nanoindentation has become the primary tool for characterising biological materials, as it allows to relate structural changes to variations in mechanical properties on small scales. However, the respective theoretical background and associated interpretation of the parameters measured via indentation derives largely from research on 'traditional' engineering materials such as metals or ceramics. Here, we discuss the functional relevance of indentation hardness in biological materials by presenting a meta-analysis of its relationship with indentation modulus. Across seven orders of magnitude, indentation hardness was directly proportional to indentation modulus. Using a lumped parameter model to deconvolute indentation hardness into components arising from reversible and irreversible deformation, we establish criteria which allow to interpret differences in indentation hardness across or within biological materials. The ratio between hardness and modulus arises as a key parameter, which is related to the ratio between irreversible and reversible deformation during indentation, the material's yield strength, and the resistance to irreversible deformation, a material property which represents the energy required to create a unit volume of purely irreversible deformation. Indentation hardness generally increases upon material dehydration, however to a larger extent than expected from accompanying changes in indentation modulus, indicating that water acts as a 'plasticiser'. A detailed discussion of the role of indentation hardness, modulus and toughness in damage control during sharp or blunt indentation yields comprehensive guidelines for a performance-based ranking of biological materials, and suggests that quasi-plastic deformation is a frequent yet poorly understood damage mode, highlighting an important area of future research. Instrumented

  19. A numerical reference model for themomechanical subduction

    DEFF Research Database (Denmark)

    Quinquis, Matthieu; Chemia, Zurab; Tosi, Nicola

    2010-01-01

    for thermomechanical subduction. This reference setup will facilitate comparisons of a series of numerical models that focus on different aspects of subduction, such as the effects of elasticity on the stress distribution, the energetic impact of phase transformations or the influence of devolatilization reactions...

  20. A dual triangular pyramidal indentation technique based on FEA solutions for Material property evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minsoo; Hyun, Hong Chul [Sogana Univ., Seoul (Korea, Republic of); Lee, Jin Haeng; Lee, Hyungyil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-01-15

    In this study, we suggest a method for material property evaluation by dual triangular pyramidal indenters using the reverse analysis. First, we demonstrated that load displacement curves of conical and triangular pyramidal indenters are different for the same material. For this reason, an independent research on the triangular pyramidal indenter is needed. From FE indentation analyses on various materials, we then investigated the relationships among material properties, indentation parameters and load displacement curves. From this, we established property evaluation formula using dual triangular pyramidal indenters having two different half included angles. The approach provides the values of elastic modulus, yield strength and strain hardening exponent within an average error of 3% for various materials.

  1. [Social classes and poverty].

    Science.gov (United States)

    Benach, Joan; Amable, Marcelo

    2004-05-01

    Social classes and poverty are two key social determinants fundamental to understand how disease and health inequalities are produced. During the 90's in Spain there has been a notable oscillation in the inequality and poverty levels, with an increase in the middle of the decade when new forms of social exclusion, high levels of unemployment and great difficulties in accessing the labour market, especially for those workers with less resources, emerged. Today society is still characterized by a clear social stratification and the existence of social classes with a predominance of high levels of unemployment and precarious jobs, and where poverty is an endemic social problem much worse than the EU average. To diminish health inequalities and to improve the quality of life will depend very much on the reduction of the poverty levels and the improvement of equal opportunities and quality of employment. To increase understanding of how social class and poverty affect public health, there is a need to improve the quality of both information and research, and furthermore planners and political decision makers must take into account those determinants when undertaking disease prevention and health promotion.

  2. Alleviating energy poverty: Indian experience

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Garima

    2010-09-15

    Energy services play an important role in human welfare. India faces acute energy poverty indicating lack of access of clean energy fuels. Access to electricity is limited to 56% households in India and about 89% of rural households depend on polluting energy sources. Energy poverty impacts income poverty as poor find it difficult to acquire high priced cleaner fuels. It also adversely impacts the socio economic conditions of women. The paper highlights the linkage of energy poverty with income poverty and gender inequality. It analyses measures taken to alleviate energy poverty and recommends regulatory and policy measures as way forward.

  3. Defining poverty as distinctively human

    Directory of Open Access Journals (Sweden)

    H.P.P. Lötter

    2007-05-01

    Full Text Available While it is relatively easy for most people to identify human beings suffering from poverty, it is rather more difficult to come to a proper understanding of poverty. In this article the author wants to deepen our understanding of poverty by interpreting the conventional definitions of poverty in a new light. The article starts with a defence of a claim that poverty is a concept uniquely applicable to humans. It then present a critical discussion of the distinction between absolute and relative poverty and it is then argued that a revision of this distinction can provide general standards applicable to humans everywhere.

  4. Reference point indentation is not indicative of whole mouse bone measures of stress intensity fracture toughness.

    Science.gov (United States)

    Carriero, Alessandra; Bruse, Jan L; Oldknow, Karla J; Millán, José Luis; Farquharson, Colin; Shefelbine, Sandra J

    2014-12-01

    Bone fragility is a concern for aged and diseased bone. Measuring bone toughness and understanding fracture properties of the bone are critical for predicting fracture risk associated with age and disease and for preclinical testing of therapies. A reference point indentation technique (BioDent) has recently been developed to determine bone's resistance to fracture in a minimally invasive way by measuring the indentation distance increase (IDI) between the first and last indentations over cyclic indentations in the same position. In this study, we investigate the relationship between fracture toughness KC and reference point indentation parameters (i.e. IDI, total indentation distance (TID) and creep indentation distance (CID)) in bones from 38 mice from six types (C57Bl/6, Balb, oim/oim, oim/+, Phospho1(-/-) and Phospho1 wild type counterpart). These mice bone are models of healthy and diseased bone spanning a range of fracture toughness from very brittle (oim/oim) to ductile (Phospho1(-/-)). Left femora were dissected, notched and tested in 3-point bending until complete failure. Contralateral femora were dissected and indented in 10 sites of their anterior and posterior shaft surface over 10 indentation cycles. IDI, TID and CID were measured. Results from this study suggest that reference point indentation parameters are not indicative of stress intensity fracture toughness in mouse bone. In particular, the IDI values at the anterior mid-diaphysis across mouse types overlapped, making it difficult to discern differences between mouse types, despite having extreme differences in stress intensity based toughness measures. When more locations of indentation were considered, the normalised IDIs could distinguish between mouse types. Future studies should investigate the relationship of the reference point indentation parameters for mouse bone in other material properties of the bone tissue in order to determine their use for measuring bone quality. Copyright © 2014

  5. Indentation size effect of Y-TZP dental ceramics.

    Science.gov (United States)

    Majić Renjo, Marijana; Ćurković, Lidija; Štefančić, Sanja; Ćorić, Danko

    2014-12-01

    The purpose of this study was to investigate and analyze the indentation size effect (ISE) in Vickers hardness of monolithic yttria partially stabilized zirconia (Y-TZP) dental ceramics without and with the addition of dental dye A3. The ISE is analyzed using the Mayer law, a proportional specimen resistance (PSR) model and a modified proportional specimen resistance (MPSR) model. Two samples of Y-TZP dental ceramics, trade names BruxZir (provided by Glidewell Laboratories, CA, USA), were investigated. The first sample was polished Y-TZP and the second sample was polished Y-TZP with the addition of dental dye A3, by VITA Classical Shade Guide. The Vickers hardness was measured under the following loads: 0.49N, 0.98N, 1.96N, 4.90, 9.81N and 29.42N. Thirty indentations were made on each sample, under each load. Relationships between the applied load, F, and the resulting indentation size, d, have been analyzed by the Mayer law, the PSR model and the MPSR model. The Meyer index (n) for both Y-TZP dental ceramics is less than 2, which indicates that hardness is dependent on test loads. The PSR model and the MPSR model were used to calculate "true" Vickers hardness or load-independent hardness. All applied mathematical models are suitable for the data analysis, which is confirmed with high correlation coefficients, but the best correlation between measured values and mathematical models was achieved with the MPSR model with a correlation coefficient of 0.9999. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Estimation of Maximum Magnitudes of Subduction Earthquakes

    Science.gov (United States)

    Muldashev, Iskander; Sobolev, Stephan

    2017-04-01

    Even though methods of instrumentally observing earthquakes at subduction zones have rapidly improved in recent decades, the characteristic recurrence interval of giant subduction earthquakes (Mw>8.5) is much larger than the currently available observational record and therefore the necessary conditions for giant earthquakes are not clear. However, the statistical studies have recognized the importance of the slab shape and its surface roughness, state of the strain of the upper plate and thickness of sediments filling the trenches. Here we apply cross-scale seismic cycle modeling technique (Sobolev and Muldashev, under review) to study key factors controlling maximum magnitudes of earthquakes in subduction zones. Our models employ elasticity, non-linear transient viscous rheology and rate-and-state friction. They generate spontaneous earthquake sequences and by using adaptive time-step algorithm, recreate the deformation process as observed naturally during seismic cycle and multiple seismic cycles. We explore effects of slab geometry, megathrust friction coefficients, and convergence rates on the magnitude of earthquakes. We found that the low-angle subduction (largest effect) and low static friction, likely caused by thick sediments in the subduction channel (smaller effect) are the key factors controlling magnitude of great earthquakes, while the change of subduction velocity from 10 to 3.5 cm/yr has much lower effect. Modeling results also suggest that thick sediments in the subduction channel causing low static friction, result in neutral or compressive deformation in the overriding plate for low-angle subduction zones in agreement with observations for the giant earthquakes. The model also predicts the magnitudes of the largest possible earthquakes for subduction zones of given dipping angles. We demonstrate that our predictions are consistent with all known giant subduction earthquakes of 20th and 21st centuries and with estimations for historical

  7. Waging War on Poverty: Poverty Trends Using a Historical Supplemental Poverty Measure

    Science.gov (United States)

    Fox, Liana E.; Wimer, Christopher; Garfinkel, Irwin; Kaushal, Neeraj; Waldfogel, Jane

    2015-01-01

    Using data from the Consumer Expenditure Survey and the March Current Population Survey, we provide poverty estimates for 1967 to 2012 based on a historical Supplemental Poverty Measure (SPM). During this period, poverty, as officially measured, has stagnated. However, the official poverty measure (OPM) does not account for the effect of near-cash transfers on the financial resources available to families, an important omission since such transfers have become an increasingly important part of government anti-poverty policy. Applying the historical SPM, which does count such transfers, we find that trends in poverty have been more favorable than the OPM suggests and that government policies have played an important and growing role in reducing poverty—a role that is not evident when the OPM is used to assess poverty. We also find that government programs have played a particularly important role in alleviating child poverty and deep poverty, especially during economic downturns. PMID:26347369

  8. Poverty Mapping Project: Small Area Estimates of Poverty and Inequality

    Data.gov (United States)

    National Aeronautics and Space Administration — The Small Area Estimates of Poverty and Inequality data set consists of consumption-based poverty, inequality and related measures for subnational administrative...

  9. Poverty Mapping Project: Poverty and Food Security Case Studies

    Data.gov (United States)

    National Aeronautics and Space Administration — The Poverty and Food Security Case Studies dataset consists of small area estimates of poverty, inequality, food security and related measures for subnational...

  10. Attitudes towards poverty

    Directory of Open Access Journals (Sweden)

    Andrzej Derdziuk

    2015-04-01

    Full Text Available Poverty, perceived as a lack of basic consumer goods, gives rise to a whole range of outcomes which affect not only the material dimension of human existence, but also influence social relations and references to spiritual values. Attitudes which could be associated with involuntary and unacceptable poverty include: doubt in the Divine Providence, bitterness, jealousy and envy, blaming others, lack of gratitude and in perceiving good, laziness, lack of initiative, escalating demands, gluttony and greed as well as meanness. However, joy, peace, freedom and solidarity with the poor, as well as work and enterprise, are symptoms of evangelical attitudes of the poor in spirit. Attitudes to poverty point to a wide range of human behaviours towards possessions and in effect, reveal an individual’s sense of value.

  11. A method to separate and quantify the effects of indentation size, residual stress and plastic damage when mapping properties using instrumented indentation

    International Nuclear Information System (INIS)

    Hou, X D; Jennett, N M

    2017-01-01

    Instrumented indentation is a convenient and increasingly rapid method of high resolution mapping of surface properties. There is, however, significant untapped potential for the quantification of these properties, which is only possible by solving a number of serious issues that affect the absolute values for mechanical properties obtained from small indentations. The three most pressing currently are the quantification of: the indentation size effect (ISE), residual stress, and pile-up and sink-in—which is itself affected by residual stress and ISE. Hardness based indentation mapping is unable to distinguish these effects. We describe a procedure that uses an elastic modulus as an internal reference and combines the information available from an indentation modulus map, a hardness map, and a determination of the ISE coefficient (using self-similar geometry indentation) to correct for the effects of stress, pile up and the indentation size effect, to leave a quantified map of plastic damage and grain refinement hardening in a surface. This procedure is used to map the residual stress in a cross-section of the machined surface of a previously stress free metal. The effect of surface grinding is compared to milling and is shown to cause different amounts of work hardening, increase in residual stress, and surface grain size reduction. The potential use of this procedure for mapping coatings in cross-section is discussed. (paper)

  12. A method to separate and quantify the effects of indentation size, residual stress and plastic damage when mapping properties using instrumented indentation

    Science.gov (United States)

    Hou, X. D.; Jennett, N. M.

    2017-11-01

    Instrumented indentation is a convenient and increasingly rapid method of high resolution mapping of surface properties. There is, however, significant untapped potential for the quantification of these properties, which is only possible by solving a number of serious issues that affect the absolute values for mechanical properties obtained from small indentations. The three most pressing currently are the quantification of: the indentation size effect (ISE), residual stress, and pile-up and sink-in—which is itself affected by residual stress and ISE. Hardness based indentation mapping is unable to distinguish these effects. We describe a procedure that uses an elastic modulus as an internal reference and combines the information available from an indentation modulus map, a hardness map, and a determination of the ISE coefficient (using self-similar geometry indentation) to correct for the effects of stress, pile up and the indentation size effect, to leave a quantified map of plastic damage and grain refinement hardening in a surface. This procedure is used to map the residual stress in a cross-section of the machined surface of a previously stress free metal. The effect of surface grinding is compared to milling and is shown to cause different amounts of work hardening, increase in residual stress, and surface grain size reduction. The potential use of this procedure for mapping coatings in cross-section is discussed.

  13. EVALUATION OF METALLIC MATERIALS PLASTICITY BY DYNAMIC INDENTATION METHOD

    Directory of Open Access Journals (Sweden)

    V. A. Rudnitsky

    2017-01-01

    Full Text Available The method of plasticity test of metallic materials realized by means of a dynamic dimpling of material by a spherical tip is offered. The measured value of plasticity is defined by a ratio of plastic and complete deformations in the formed indentation which considers influence of an elastic modulus of material. The dependence connecting plasticity and dynamic hardness of materials is received. Experiments on metals from 70 to 380 GPA having an elastic modulus and hardness up to 62 HRC are made.

  14. Optical measuring system for the geometrical parameters of Rockwell and Vickers diamond hardness indenters

    Science.gov (United States)

    Zhang, Liqiong; Cui, Yuanyuan; Zhang, Feng

    2017-11-01

    Hardness testing is widely used for characterizing the mechanical properties of materials. However, the measured hardness values in hardness measurements are strongly influenced by the geometrical parameters of diamond hardness indenters. In the most severe case, the geometrical error of the diamond indenter, Rockwell hardness measurements in particular, leads to be about 50% hardness measurement uncertainty. It has been generally recognized for many years that the geometry of diamond indenters must be calibrated or verified before use to correct the hardness value for each indenter and improve the hardness measurement uncertainty. The contact-based calibration methods and the contactless based optical measuring methods are two typical ways to calibrate the geometrical form of an indenter at present. The contact-based calibration methods characterized by large measurement range of tens of mm with nanometer resolution, has a time-consuming measurement process, the contactless based optical measuring methods have become a general trend. In this work, an optical measuring system, which employs the combination of an interferometric microscope and a profile projection technique, is presented to measure and calibrate the geometrical parameters of Rockwell and Vickers diamond hardness indenters in National Institute of Metrology of China. Initial experiments demonstrated that the angle and axis angle measurement of indenter are achieved with accuracy of 0.1°, the straightness deviation of Rockwell indenters is less than 2μm, the radius measurement uncertainty of the tip of Rockwell indenters is better than 5μm.

  15. Requirements for investigating the temperature-dependent fracture behavior of irradiated materials by indentation

    Energy Technology Data Exchange (ETDEWEB)

    Sacksteder, Irène, E-mail: irene.sacksteder@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, Eggenstein-Leopoldshafen (Germany); Hostettler, Simon [Synton-MDP Inc., Nidau (Switzerland); Charbonneau, Grégoire; Albinski, Bartlomiej; Schneider, Hans-Christian [Karlsruhe Institute of Technology, Institute for Applied Materials, Eggenstein-Leopoldshafen (Germany)

    2013-10-15

    Highlights: • A custom-made indenter is designed for indentations at high temperature. • The instrumented indentation technique at high temperature will be used to investigate temperature dependent fracture mechanisms in structural materials. • A finite-element based model has been validated with a view to predict crack initiation and propagation in Eurofer97 and tungsten-like materials. -- Abstract: The instrumented indentation technique is an interesting testing tool to examine temperature-dependent fracture mechanisms. It is planned to be used to generate cracks at defined temperatures in hard and brittle metallic materials. The present study describes the properties needed for the use of a new type of indenter operating at high temperature. The indenter was designed to meet mechanical and thermal requirements and other constraints relating to the operation of functional units of the indentation instrument. Additionally, a finite element model has been built with a view to predict indentation induced cracks in Eurofer97 and tungsten. The model has been validated both with the theory of Hertz and experimentally by comparison with indentation curves.

  16. Progress in Indentation Study of Materials via Both Experimental and Numerical Methods

    Directory of Open Access Journals (Sweden)

    Mao Liu

    2017-10-01

    Full Text Available Indentation as a method to characterize materials has a history of more than 117 years. However, to date, it is still the most popular way to measure the mechanical properties of various materials at microscale and nanoscale. This review summarizes the background and the basic principle of processing by indentation. It is demonstrated that indentation is an effective and efficient method to identify mechanical properties, such as hardness, Young’s modulus, etc., of materials at smaller scale, when the traditional tensile tests could not be applied. The review also describes indentation process via both experimental tests and numerical modelling in recent studies.

  17. Impacts of Policies on Poverty: The Definition of Poverty

    OpenAIRE

    Bellù, Lorenzo Giovanni; Liberati, Paolo

    2005-01-01

    This module illustrates how poverty can be defined in the context of policy impact analysis. After reporting and discussing the definition of poverty as “the lack of, or the inability to achieve, a socially acceptable standard of living”, it discusses the mono-dimensional and multi-dimensional approaches to the definition of poverty. Furthermore, the module focuses on the absolute and the relative concept of poverty, also drawing some analogies and differences with the concept of food secu...

  18. Impacts of Policies on Poverty. Relative Poverty Lines

    OpenAIRE

    Bellù, Lorenzo Giovanni; Liberati, Paolo

    2005-01-01

    This module illustrates how to define “relative” poverty lines, i.e. poverty lines based on approaches that consider the welfare position of each individual or household in relation to the welfare position of other individuals or households belonging to the same community. In particular, the module, after emphasizing the importance of the relative poverty concept in policy work, discusses two methods to define relative poverty lines: a) the “income levels” method; and b) the “income positions...

  19. Biofuels, poverty, and growth

    DEFF Research Database (Denmark)

    Arndt, Channing; Benfica, Rui; Tarp, Finn

    2010-01-01

    Mozambique's annual economic growth by 0.6 percentage points and reduces the incidence of poverty by about 6 percentage points over a 12-year phase-in period. Benefits depend on production technology. An outgrower approach to producing biofuels is more pro-poor, due to the greater use of unskilled labor......This paper assesses the implications of large-scale investments in biofuels for growth and income distribution. We find that biofuels investment enhances growth and poverty reduction despite some displacement of food crops by biofuels. Overall, the biofuel investment trajectory analyzed increases...

  20. Origin and dynamics of depositionary subduction margins

    Science.gov (United States)

    Vannucchi, Paola; Morgan, Jason P.; Silver, Eli A.; Kluesner, Jared W.

    2016-06-01

    Here we propose a new framework for forearc evolution that focuses on the potential feedbacks between subduction tectonics, sedimentation, and geomorphology that take place during an extreme event of subduction erosion. These feedbacks can lead to the creation of a "depositionary forearc," a forearc structure that extends the traditional division of forearcs into accretionary or erosive subduction margins by demonstrating a mode of rapid basin accretion during an erosive event at a subduction margin. A depositionary mode of forearc evolution occurs when terrigenous sediments are deposited directly on the forearc while it is being removed from below by subduction erosion. In the most extreme case, an entire forearc can be removed by a single subduction erosion event followed by depositionary replacement without involving transfer of sediments from the incoming plate. We need to further recognize that subduction forearcs are often shaped by interactions between slow, long-term processes, and sudden extreme events reflecting the sudden influences of large-scale morphological variations in the incoming plate. Both types of processes contribute to the large-scale architecture of the forearc, with extreme events associated with a replacive depositionary mode that rapidly creates sections of a typical forearc margin. The persistent upward diversion of the megathrust is likely to affect its geometry, frictional nature, and hydrogeology. Therefore, the stresses along the fault and individual earthquake rupture characteristics are also expected to be more variable in these erosive systems than in systems with long-lived megathrust surfaces.

  1. Origin and dynamics of depositionary subduction margins

    Science.gov (United States)

    Vannucchi, Paola; Morgan, Jason P.; Silver, Eli; Kluesner, Jared W.

    2016-01-01

    Here we propose a new framework for forearc evolution that focuses on the potential feedbacks between subduction tectonics, sedimentation, and geomorphology that take place during an extreme event of subduction erosion. These feedbacks can lead to the creation of a “depositionary forearc,” a forearc structure that extends the traditional division of forearcs into accretionary or erosive subduction margins by demonstrating a mode of rapid basin accretion during an erosive event at a subduction margin. A depositionary mode of forearc evolution occurs when terrigenous sediments are deposited directly on the forearc while it is being removed from below by subduction erosion. In the most extreme case, an entire forearc can be removed by a single subduction erosion event followed by depositionary replacement without involving transfer of sediments from the incoming plate. We need to further recognize that subduction forearcs are often shaped by interactions between slow, long-term processes, and sudden extreme events reflecting the sudden influences of large-scale morphological variations in the incoming plate. Both types of processes contribute to the large-scale architecture of the forearc, with extreme events associated with a replacive depositionary mode that rapidly creates sections of a typical forearc margin. The persistent upward diversion of the megathrust is likely to affect its geometry, frictional nature, and hydrogeology. Therefore, the stresses along the fault and individual earthquake rupture characteristics are also expected to be more variable in these erosive systems than in systems with long-lived megathrust surfaces.

  2. Quantitative Hardness Measurement by Instrumented AFM-indentation.

    Science.gov (United States)

    Caron, Arnaud

    2016-11-22

    In this work, a combination of amplitude-modulated non-contact atomic force microscopy and atomic force spectroscopy is applied for instrumented hardness measurements on an Au(111) surface with atomistic resolution of single plasticity events. A careful experimental procedure is described that includes the force sensor selection, its calibration, the calibration of the cantilever deflection detection system, and the minimization of instrumental drift for accurate and reproducible force-distance measurements. Also, a method for the data analysis is presented that allows the extraction of force-penetration curves from recorded force-distance curves. A typical curve displays a clear elastic deformation regime up to the first plasticity event, or pop-in, with a length in the range of one to two Burger's vectors. Later plasticity events exhibit the same magnitude. The work of plasticity is further extracted from the measurements. Finally, the hardness is determined in combination with the indentation curve using non-contact atomic force microscopy images of the remaining indents.

  3. Phase Transformation of Metastable Austenite in Steel during Nano indentation

    International Nuclear Information System (INIS)

    Ahn, Taehong; Lee, Sung Bo; Han, Heung Nam; Park, Kyungtae

    2013-01-01

    These can produce geometrical softening accompanied by a sudden displacement excursion during load-controlled nanoindentation, which referred to in the literature as a pop-in. In this study, phase transformation of metastable austenite to stress-induced ε martensite which causes pop-ins during nanoindentation of steel will be reported and discussed. This study investigated the relationship between pop-in behavior of austenite in the early stage of nanoindentation and formation of ε martensite based on microstructural analyses. The load-displacement curve obtained from nanoindentation revealed stepwise pop-ins in the early stage of plastic deformation. From analyses of high resolution TEM images, a cluster of banded structure under the indent turned out a juxtaposition of (111) planes of γ austenite and (0001) planes of ε martensite. The calculation of displacement along indentation axis for (111) slip system by formation of ε martensite showed that geometrical softening can also occur by ε martensite formation when considering that the stress-induced ε martensite transformation is the predominant deformation mode in the early stage of plastic deformation and its monopartial nature as well. These microstructural investigations strongly suggest that the pop-in behavior in the early stage of plastic deformation of austenite is closely related to the formation of ε martensite

  4. Phase Transformation of Metastable Austenite in Steel during Nano indentation

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Taehong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, Sung Bo; Han, Heung Nam [Seoul National Univ., Seoul (Korea, Republic of); Park, Kyungtae [Hanbat National Univ., Daejeon (Korea, Republic of)

    2013-05-15

    These can produce geometrical softening accompanied by a sudden displacement excursion during load-controlled nanoindentation, which referred to in the literature as a pop-in. In this study, phase transformation of metastable austenite to stress-induced ε martensite which causes pop-ins during nanoindentation of steel will be reported and discussed. This study investigated the relationship between pop-in behavior of austenite in the early stage of nanoindentation and formation of ε martensite based on microstructural analyses. The load-displacement curve obtained from nanoindentation revealed stepwise pop-ins in the early stage of plastic deformation. From analyses of high resolution TEM images, a cluster of banded structure under the indent turned out a juxtaposition of (111) planes of γ austenite and (0001) planes of ε martensite. The calculation of displacement along indentation axis for (111) slip system by formation of ε martensite showed that geometrical softening can also occur by ε martensite formation when considering that the stress-induced ε martensite transformation is the predominant deformation mode in the early stage of plastic deformation and its monopartial nature as well. These microstructural investigations strongly suggest that the pop-in behavior in the early stage of plastic deformation of austenite is closely related to the formation of ε martensite.

  5. Quasi-Static Indentation Analysis of Carbon-Fiber Laminates.

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, Timothy [Sandia National Lab. (SNL-CA), Livermore, CA (United States); English, Shawn Allen [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Nelson, Stacy Michelle [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2015-12-01

    A series of quasi - static indentation experiments are conducted on carbon fiber reinforced polymer laminates with a systematic variation of thicknesses and fixture boundary conditions. Different deformation mechanisms and their resulting damage mechanisms are activated b y changing the thickn ess and boundary conditions. The quasi - static indentation experiments have been shown to achieve damage mechanisms similar to impact and penetration, however without strain rate effects. The low rate allows for the detailed analysis on the load response. Moreover, interrupted tests allow for the incremental analysis of various damage mechanisms and pr ogressions. The experimentally tested specimens are non - destructively evaluated (NDE) with optical imaging, ultrasonics and computed tomography. The load displacement responses and the NDE are then utilized in numerical simulations for the purpose of model validation and vetting. The accompanying numerical simulation work serves two purposes. First, the results further reveal the time sequence of events and the meaning behind load dro ps not clear from NDE . Second, the simulations demonstrate insufficiencies in the code and can then direct future efforts for development.

  6. Noble Gases Trace Earth's Subducted Water Flux

    Science.gov (United States)

    Smye, A.; Jackson, C.; Konrad-Schmolke, M.; Parman, S. W.; Ballentine, C. J.

    2016-12-01

    Volatile elements are transported from Earth's surface reservoirs back into the mantle during subduction of oceanic lithosphere [e.g. 1]. Here, we investigate the degree to which the fate of slab-bound noble gases and water are linked through the subduction process. Both water and noble gases are soluble in ring-structured minerals, such as amphibole, that are common constituents of subducted oceanic lithosphere. Heating and burial during subduction liberates noble gases and water from minerals through a combination of diffusion and dissolution. Combining a kinetic model, parameterized for noble gas fractionation in amphibole [2], with thermodynamic phase equilibria calculations, we quantify the effect of subduction dehydration on the elemental composition of slab-bound noble gases. Results show that post-arc slab water and noble gas fluxes are highly correlated. Hot subduction zones, which likely dominate over geologic history, efficiently remove noble gases and water from the down-going slab; furthermore, kinetic fractionation of noble gases is predicted to occur beneath the forearc. Conversely, hydrated portions of slab mantle in cold subduction zones transport noble gases and water to depths exceeding 200 km. Preservation of seawater-like abundances of Ar, Kr and Xe in the convecting mantle [1] implies that recycling of noble gases and water occurred during cold subduction and that the subduction efficiency of these volatile elements has increased over geological time, driven by secular cooling of the mantle. [1] Holland, G. and Ballentine, C. (2006). Nature 441, 186-191. [2] Jackson et al. (2013). Nat.Geosci. 6, 562-565.

  7. high-poverty schools

    African Journals Online (AJOL)

    leadership in high-poverty schools? Investigations conducted at six successful ..... (not only motivate) others, to build team spirit and pride, and to seek and explore every possible opportunity, source and ..... The key ingredients of school success appear to'be the principal's passion for upliftment, the teachers' commitment ...

  8. Poverty and Political Culture

    NARCIS (Netherlands)

    Gouda, Frances

    1995-01-01

    Frances Gouda examines the different rhetorical approaches to poverty, charity, and social welfare embraced by intellectuals and policy-makers in the Netherlands and France in the period 1815 - 1854. She explores the different discourses in Holland and France about the revolutionary threat implicit

  9. Poverty in Palanpur

    NARCIS (Netherlands)

    Lanjouw, Peter; Stern, Nicholas

    The meaning and identification of poverty are examined using three indicators of standard of living in the North Indian village of Palanpur. The first is intended as a measure of "apparent prosperity" based on the personal assessments of investigators after intensive field work in the village over

  10. Poverty + Hunger = Global Issues.

    Science.gov (United States)

    Schwartz, Richard H.

    1983-01-01

    Geography teachers can use mathematics to teach fourth, fifth, and sixth grade students about critical global issues. Five sample problems concerning population, poverty, waste, the arms race, and hunger are presented. The global issue related to each problem is discussed, and the solution and mathematical skill are provided. (RM)

  11. Producing Against Poverty

    NARCIS (Netherlands)

    Ypeij, Annelou

    2000-01-01

    Producing against Poverty is an anthropological research on micro-entrepreneurs in Lima, Peru. It analyses the way micro-producers accumulate capital. The anthropological approach of the book starts with an analysis of the daily lives of the micro-producers. Its gender approach makes a comparison

  12. Child Poverty & Public Policy.

    Science.gov (United States)

    Chafel, Judith A., Ed.

    This collection documents how far we still are in the United States from putting our knowledge about child well being and policy into practice. It provides an overview of the changing nature of child poverty in the United States through the contributions of authors who use a number of qualitative and quantitative approaches to look at children in…

  13. Strategies Against Poverty.

    Science.gov (United States)

    Riessman, Frank

    The major antipoverty strategies of the 1960's are analyzed--the conflict model of Alinsky, the welfare crisis approach of Cloward and Piven, and the new careers viewpoint of Riessman and Pearl. The latter strategy is said to have a greater "multiplier effect" on poverty than other approaches. Discussed are such specific strategies in…

  14. Poverty-related diseases (PRDs)

    NARCIS (Netherlands)

    Makoge, Valerie; Maat, Harro; Vaandrager, Lenneke; Koelen, Maria

    2017-01-01

    Background: In Cameroon, poverty-related diseases (PRDs) are a major public health concern. Research and policies addressing PRDs are based on a particular understanding of the interaction between poverty and disease, usually an association between poverty indicators and health indicators for a

  15. Energy poverty in rural Bangladesh

    International Nuclear Information System (INIS)

    Barnes, Douglas F.; Khandker, Shahidur R.; Samad, Hussain A.

    2011-01-01

    Energy poverty is a well-established concept among energy and development specialists. International development organizations frequently cite energy-poverty alleviation as a necessary condition to reduce income poverty. Several approaches used to measure energy poverty over the past 20 years have defined the energy poverty line as the minimum quantity of physical energy needed to perform such basic tasks as cooking and lighting. This paper uses a demand-based approach to define the energy poverty line as the threshold point at which energy consumption begins to rise with increases in household income. At or below this threshold point, households consume a bare minimum level of energy and should be considered energy poor. This approach was applied using cross-sectional data from a comprehensive 2004 household survey representative of rural Bangladesh. The findings suggest that some 58 percent of rural households in Bangladesh are energy poor, versus 45 percent that are income poor. The findings also suggest that policies to support rural electrification and greater use of improved biomass stoves might play a significant role in reducing energy poverty. - Research Highlights: →We estimate energy poverty for rural Bangladesh adopting a demand-based approach. →Findings suggest that energy poverty does not necessarily follow the same pattern as income poverty. →Access to modern energy and efficient use of traditional energy help alleviate energy poverty. →Energy poverty indicator can help track the effectiveness of a wide range of energy policies.

  16. Poverty on the Cards 2016

    NARCIS (Netherlands)

    Stella Hoff; Jean Marie Wildeboer Schut; Benedikt Goderis; Cok Vrooman

    2016-01-01

    Decline in poverty since 2014 According to SCP’s ‘modest but adequate’ poverty threshold, 7.6% of the Dutch population were living in poverty in 2014. That figure is expected to have fallen to 7% in 2016. If the promised measures to improve purchasing power are implemented,

  17. Influence of indenter geometry on the frictional sliding resistance of tooth enamel

    Directory of Open Access Journals (Sweden)

    M.V. Swain

    2017-12-01

    Full Text Available Indentation force-displacement and sliding scratch resistance measurements have been conducted on orangutan tooth enamel. Tests were made with a corner-cube (CC, Berkovich, as well as spherical (nominally 1 μm and 5 μm radius indenters. Indentation loads ranged from 100 to 5000 μN and were also made on fused silica to calibrate the indenter tips. The frictional force as a function of sliding distance was measured with the atomic force microscope (AFM option on the indenter system as well as using a high precision AFM and scanning electron microscope (SEM. The frictional resistance was found to be almost constant with indenter load for the CC and Berkovich indenters; for the CC, it depended upon the orientation of the sliding indenter. For the spherical indenters, the 1 μm showed a sharp increase in frictional resistance with increasing load whereas for the 5 μm tip there was minimal change. Observations of the resultant scratches showed ploughing/cutting with the sharp indenters and a transition from an “ironing” like deformation for all the 5 μm tests and for the low load 1 μm tip with ploughing at the heaviest load. In the case of the sharp tips a “metallic” like discontinuous swarf removal process was evident. It was found that the frictional resistance force scaled with the effective rake angle of the indenter tips. Implications of the current observations for understanding tooth wear are considered.

  18. Poverty and Climate Change

    Science.gov (United States)

    van der Vink, G.; Franco, E.; Fuckar, N. S.; Kalmbach, E. R.; Kayatta, E.; Lankester, K.; Rothschild, R. E.; Sarma, A.; Wall, M. L.

    2008-05-01

    The poor are disproportionately vulnerable to environmental change because they have the least amount of resources with which to adapt, and they live in areas (e.g. flood plains, low-lying coastal areas, and marginal drylands) that are particularly vulnerable to the manifestations of climate change. By quantifying the various environmental, economic, and social factors that can contribute to poverty, we identify populations that are most vulnerable to poverty and poverty traps due to environmental change. We define vulnerability as consisting of risk (probability of event and exposed elements), resiliency, and capacity to respond. Resiliency captures the social system's ability to absorb a natural disaster while retaining the same basic structure, organization, and ways of functioning, as well as its general capacity to adapt to stress and change. Capacity to respond is a surrogate for technical skills, institutional capabilities, and efficacy within countries and their economies. We use a "climate change multiplier" to account for possible increases in the frequency and severity of natural events due to climate change. Through various analytical methods, we quantify the social, political, economic, and environmental factors that contribute to poverty or poverty traps. These data sets are then used to determine vulnerability through raster multiplication in geospatial analysis. The vulnerability of a particular location to climate change is then mapped, with areas of high vulnerability clearly delineated. The success of this methodology indicates that it is indeed possible to quantify the effects of climate change on global vulnerability to natural disasters, and can be used as a mechanism to identify areas where proactive measures, such as improving adaptation or capacity to respond, can reduce the humanitarian and economic impacts of climate change.

  19. Trends in Child Poverty Using an Improved Measure of Poverty.

    Science.gov (United States)

    Wimer, Christopher; Nam, JaeHyun; Waldfogel, Jane; Fox, Liana

    2016-04-01

    The official measure of poverty has been used to assess trends in children's poverty rates for many decades. But because of flaws in official poverty statistics, these basic trends have the potential to be misleading. We use an augmented Current Population Survey data set that calculates an improved measure of poverty to reexamine child poverty rates between 1967 and 2012. This measure, the Anchored Supplemental Poverty Measure, is based partially on the US Census Bureau and Bureau of Labor Statistics' new Supplemental Poverty Measure. We focus on 3 age groups of children, those aged 0 to 5, 6 to 11, and 12 to 17 years. Young children have the highest poverty rates, both historically and today. However, among all age groups, long-term poverty trends have been more favorable than official statistics would suggest. This is entirely due to the effect of counting resources from government policies and programs, which have reduced poverty rates substantially for children of all ages. However, despite this progress, considerable disparities in the risk of poverty continue to exist by education level and family structure. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  20. Combatting poverty in South Africa

    OpenAIRE

    2015-01-01

    M.Com. (Economics) Combating poverty is at the frontier of analyses in South Africa today. The study to combat poverty in South Africa is six-fold. After setting the nature of the study to be pursued in Chapter 1, the dissertation analyses the theories of poverty in Chapter 2. The record of poverty in South Africa is analysed in Chapter 3. Chapter 4 focuses on the methods to combat poverty in South Africa. Chapter 5 is a summary of the main findings of the study. A proposed structure plan ...

  1. Explaining the Evolution of Poverty

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Azhar; Jones, Edward Samuel

    2012-01-01

    We provide a comprehensive approach for analyzing the evolution of poverty using Mozambique as a case study. Bringing together data from disparate sources, we develop a novel “back-casting” framework that links a dynamic computable general equilibrium model to a micro-simulation poverty module....... This framework provides a new approach to explaining and decomposing the evolution of poverty, as well as to examining rigorously the coherence between poverty, economic growth, and inequality outcomes. Finally, various simple but useful and rarely-applied approaches to considering regional changes in poverty...

  2. Study of indentation induced cracks in MoSi2-reaction bonded SiC ...

    Indian Academy of Sciences (India)

    Mo melt into a preform of commercial SiC and petroleum coke powder. The infiltrated sample had a density > 92% of the theoretical density (TD) and microstructurally contained SiC, MoSi2, residual Si and unreacted C. The material was tested for indentation fracture toughness at room temperature with a Vicker's indenter ...

  3. Indentations and Starting Points in Traveling Sales Tour Problems: Implications for Theory

    Science.gov (United States)

    MacGregor, James N.

    2012-01-01

    A complete, non-trivial, traveling sales tour problem contains at least one "indentation", where nodes in the interior of the point set are connected between two adjacent nodes on the boundary. Early research reported that human tours exhibited fewer such indentations than expected. A subsequent explanation proposed that this was because…

  4. A novel sample preparation method to avoid influence of embedding medium during nano-indentation

    Science.gov (United States)

    Yujie Meng; Siqun Wang; Zhiyong Cai; Timothy M. Young; Guanben Du; Yanjun Li

    2012-01-01

    The effect of the embedding medium on the nano-indentation measurements of lignocellulosic materials was investigated experimentally using nano-indentation. Both the reduced elastic modulus and the hardness of nonembedded cell walls were found to be lower than those of the embedded samples, proving that the embedding medium used for specimen preparation on cellulosic...

  5. Temperature-dependent indentation behavior of transformation-toughened zirconia-based ceramics

    Science.gov (United States)

    Tikare, Veena; Heuer, Arthur H.

    1991-01-01

    Indentation behavior of Ce-TZP, Y-TZP, and Mg-PSZ between room temperature and 1300 C was investigated. Hardness decreased with increasing temperature for all three materials, but indentation cracking increased with increasing temperature. The opposing temperature dependences are discussed in terms of dislocation and transformation plasticity.

  6. Crystallographic Analysis of Nucleation at Hardness Indentations in High-Purity Aluminum

    DEFF Research Database (Denmark)

    Xu, Chaoling; Zhang, Yubin; Lin, Fengxiang

    2016-01-01

    Nucleation at Vickers hardness indentations has been studied in high-purity aluminum cold-rolled 12 pct. Electron channeling contrast was used to measure the size of the indentations and to detect nuclei, while electron backscattering diffraction was used to determine crystallographic orientation...

  7. Mechanical properties study of particles reinforced aluminum matrix composites by micro-indentation experiments

    Directory of Open Access Journals (Sweden)

    Yuan Zhanwei

    2014-04-01

    Full Text Available By using instrumental micro-indentation technique, the microhardness and Young’s modulus of SiC particles reinforced aluminum matrix composites were investigated with micro-compression-tester (MCT. The micro-indentation experiments were performed with different maximum loads, and with three loading speeds of 2.231, 4.462 and 19.368 mN/s respectively. During the investigation, matrix, particle and interface were tested by micro-indentation experiments. The results exhibit that the variations of Young’s modulus and microhardness at particle, matrix and interface were highly dependent on the loading conditions (maximum load and loading speed and the locations of indentation. Micro-indentation hardness experiments of matrix show the indentation size effects, i.e. the indentation hardness decreased with the indentation depth increasing. During the analysis, the effect of loading conditions on Young’s modulus and microhardness were explained. Besides, the elastic–plastic properties of matrix were analyzed. The validity of calculated results was identified by finite element simulation. And the simulation results had been preliminarily analyzed from statistical aspect.

  8. Determining the Elastic Modulus of Compliant Thin Films Supported on Substrates from Flat Punch Indentation Measurements

    Science.gov (United States)

    M.J. Wald; J.M. Considine; K.T. Turner

    2013-01-01

    Instrumented indentation is a technique that can be used to measure the elastic properties of soft thin films supported on stiffer substrates, including polymer films, cellulosic sheets, and thin layers of biological materials. When measuring thin film properties using indentation, the effect of the substrate must be considered. Most existing models for determining the...

  9. Nanoindentation hardness measurements using real-shape indenters: application to extremely hard and elastic materials

    Science.gov (United States)

    Martínez, E.; Esteve, J.

    We study the technique of nanoindentation hardness measurement applied to extremely hard and elastic thin films. We do the study with the aid of Hertz's solutions for elastic contacts. The effect of different apical angles in ideally sharp conical diamond indenters is analyzed. In addition, the blunt tip shape of practical diamond indenters is discussed. The area function of the tip of real indenters is deduced from experimental nanoindentation measurements performed with these indenters on fused quartz. Triangular-base pyramidal indenters with Berkovich and cube corner geometries are considered. Theoretical hardness values applying Hertz's and Oliver and Pharr's methods of analysis are obtained and compared with the experimental data deduced from nanoindentation measurements performed on very hard and elastic ta-C films. The theoretical analysis shows a necessary dependence of the calculated hardness values with the apical angle of the indenter in totally elastic materials and to some extent in elastoplastic materials. Moreover, when the indenter tip is blunt or when there are inaccuracies in the measured area function of the indenter tip, hardness values decrease for very small penetration depths. Besides, in these films, because of their very small thickness, measured hardness values also decrease for measurements with penetration depths larger than a fraction of film thickness, due to the effects of the softer substrate.

  10. A subduction zone reference frame based on slab geometry and subduction partitioning of plate motion and trench migration

    NARCIS (Netherlands)

    Schellart, W. P.

    2011-01-01

    The geometry of subducted slabs that interact with the transition zone depends critically on the partitioning of the subduction velocity (v S⊥) at the surface into its subducting plate motion component (vSP⊥) and trench migration component (vT⊥). Geodynamic models of progressive subduction

  11. On the psychology of poverty.

    Science.gov (United States)

    Haushofer, Johannes; Fehr, Ernst

    2014-05-23

    Poverty remains one of the most pressing problems facing the world; the mechanisms through which poverty arises and perpetuates itself, however, are not well understood. Here, we examine the evidence for the hypothesis that poverty may have particular psychological consequences that can lead to economic behaviors that make it difficult to escape poverty. The evidence indicates that poverty causes stress and negative affective states which in turn may lead to short-sighted and risk-averse decision-making, possibly by limiting attention and favoring habitual behaviors at the expense of goal-directed ones. Together, these relationships may constitute a feedback loop that contributes to the perpetuation of poverty. We conclude by pointing toward specific gaps in our knowledge and outlining poverty alleviation programs that this mechanism suggests. Copyright © 2014, American Association for the Advancement of Science.

  12. The Coupling of Back-arc Extension, Extrusion and Subduction Dynamics in the Eastern Mediterranean

    Science.gov (United States)

    Capitanio, Fabio A.

    2017-04-01

    Extension in the Aegean Sea and lateral Anatolian extrusion are contrasting and seemingly unrelated examples of continental tectonics In the Eastern Mediterranean. It is acknowledged that these must reconcile with the dynamics of Tethys closure and following continental collision along the convergent margin, however the underlying mechanisms have been difficult to pinpoint, thus far. Three-dimensional numerical modelling of the dynamics of subduction and coupling with the mantle and upper plates allows probing the evolution of similar areas, supporting inferences on the ultimate causes for the continental tectonics. I will present models that reproduce the force balance of subducting slabs' buoyancy, mantle flow and upper plate interiors, and emphasise the role of perturbations in the force balance that may have followed slab breakoff, collision and trench land-locking reconstructed during the oceanic closure in the Eastern Mediterranean. These perturbations lead to a range of different margin motions and strain regimes in the upper plate, from rollback and back-arc spreading, to indentation and extrusion along the collisional margin. Different spatial and temporal fingerprints are illustrated for these processes, and while the trench rollback and back-arc spreading are rather stable features, extrusion is transient. When these regimes overlap, rapid and complex rearrangements of the tectonics in the upper plate are the result. The remarkable similarity between the models' and the Eastern Mediterranean tectonic regimes and geophysical observable allows proposing viable driving mechanisms and support inferences on the Miocene-to-Pliocene evolution of this puzzling area.

  13. Quasi-static indentation modelling of aluminium specimen using finite element analysis

    Directory of Open Access Journals (Sweden)

    Mayank Nirbhay

    2017-03-01

    Full Text Available The influence of different types of rigid hemispherical and conical indenters on a rectangular specimen of aluminium has been investigated, in the small indenter test. A 3-D finite-element FE model was used to carry out the computation of the elastic-plastic solution of different rigid hemispherical and conical indenters. Three hemispherical-headed and four conical-headed indenters were designed and developed for testing. FE software ABAQUS® has been used to determine the load vs. indenter-displacement curves, reaction forces, deformation contours and Von-Mises stresses. The FE model was validated by comparing the results with the experimental data received from the Hertz Contact Theory and was found to be in reasonably good agreement.

  14. Calibrated atomic force microscope measurements of vickers hardness indentations and tip production and characterisation for scanning tunelling microscope

    DEFF Research Database (Denmark)

    Jensen, Carsten P.

    Calibrated atomic force microscope measurements of vickers hardness indentations and tip production and characterisation for scanning tunelling microscope......Calibrated atomic force microscope measurements of vickers hardness indentations and tip production and characterisation for scanning tunelling microscope...

  15. Competent poverty training.

    Science.gov (United States)

    Stabb, Sally D; Reimers, Faye A

    2013-02-01

    Despite numerous calls to the discipline, attention to poverty and social class remains minimal in psychology even though most human experience is significantly affected by social ranking. As a result, educators lack models for training in the context of poverty. Recent and concerted efforts to define and implement competency-based models for the practice of professional psychology have resulted in the creation of Competency Benchmarks (American Psychological Association, 2011). Here, these Competency Benchmarks frame the integration of best practices in working with poor and working-class clients with what we know about what constitutes good training. The result is a competency-based approach for those who are training psychologists-to-be to work effectively with economically challenged clients. © 2012 Wiley Periodicals, Inc.

  16. Poverty and development

    Directory of Open Access Journals (Sweden)

    Néstor Juan Sanabria Landazábal

    2006-07-01

    Full Text Available In this essay there is argued that the notions ofpoverty, development, quality of life and, in general, all the concepts, variables and indicators used in the explanations and theories on this type, are different points of view from the observers' interests,of the same and only social phenomenon. Therefore,there are multiple works on poverty and development. However, an approximation from the perspective of complexity must bear in mind that the development may refer to the social structure as a whole, and to the actions that modify context of the system, just when it has been ordered through the science in order to explain the reality. Therefore,there is a clase relation between poverty and development. These are different ways to see the same phenomenon, which allow us to think about the life quality from a global sense.

  17. Tourism and poverty relief

    OpenAIRE

    Blake, Adam; Arbache, Jorge Saba; Sinclair, Thea; Teles, Vladimir Kühl

    2010-01-01

    This paper examines the issue of how tourism affects poverty in the context of the effects of tourism on an economy as a whole and on particular sectors within it. A framework for analysing the channels through which tourism affects different households is developed, and a computable general equilibrium model of the Brazilian economy is used to examine the economic impact and distributional effects of tourism in Brazil. It is shown that the effects on all income groups are posi...

  18. Poverty among Foster Children: Estimates Using the Supplemental Poverty Measure

    Science.gov (United States)

    Pac, Jessica; Waldfogel, Jane; Wimer, Christopher

    2017-01-01

    We use data from the Current Population Survey and the new Supplemental Poverty Measure (SPM) to provide estimates for poverty among foster children over the period 1992 to 2013. These are the first large-scale national estimates for foster children who are not included in official poverty statistics. Holding child and family demographics constant, foster children have a lower risk of poverty than other children. Analyzing income in detail suggests that foster care payments likely play an important role in reducing the risk of poverty in this group. In contrast, we find that children living with grandparents have a higher risk of poverty than other children, even after taking demographics into account. Our estimates suggest that this excess risk is likely linked to their lower likelihood of receiving foster care or other income supports. PMID:28659651

  19. Child Poverty: Definition and Measurement.

    Science.gov (United States)

    Short, Kathleen S

    2016-04-01

    This article provides a discussion of what we mean when we refer to 'child poverty.' Many images come to mind when we discuss child poverty, but when we try to measure and quantify the extent of child poverty, we often use a very narrow concept. In this article a variety of poverty measures that are used in the United States are described and some of the differences between those measures are illustrated. In this article 3 measures are explored in detail: a relative measure of poverty that is used more often in an international context, the official US poverty measure, and a new supplemental poverty measure (SPM). The new measure differs from the other 2 because it takes into account noncash benefits that are provided to poor families. These include nutrition assistance such as food stamps, subsidized housing, and home energy assistance. The SPM also takes account of necessary expenses that families face, such as taxes and expenses related to work and health care. Comparing estimates for 2012, the SPM showed lower poverty rates for children than the other 2 measures. Because noncash benefits help those in extreme poverty, there were also lower percentages of children in extreme poverty with resources below half the SPM threshold. These results suggest that 2 important measures of poverty, the relative measure used in international comparisons, and the official poverty measure, are not able to gauge the effect of government programs on the alleviation of poverty, and the SPM illustrates that noncash benefits do help families meet their basic needs. Published by Elsevier Inc.

  20. The Possible Decapitation of a Megathrust Indenter: Evidence from Imaging of Time-dependent Microseismic Structures before and after the 2012 Mw 7.6 Nicoya, Costa Rica

    Science.gov (United States)

    Newman, A. V.; Yao, D.; Kyriakopoulos, C.; Moore-Driskell, M. M.; Hobbs, T. E.; Peng, Z.; Schwartz, S. Y.; Protti, M.; Gonzalez, V.

    2016-12-01

    We normally view the subduction megathrust surface as a constant structure throughout the seismic cycle, with the elastic loading, microseismicity, and slip occurring along it. However, using small events recorded from a uniquely dense seismic network directly over the active megathrust below Nicoya, Costa Rica, we find two different seismogenic structures with near exclusive time-dependent behavior immediately in the region of maximum coseismic slip. Microseismicity recorded at intervals between 1999 and 2009 showed an elevated topographic indenter beneath central Nicoya, and associated with a suture marking transition between Cocos-Nazca Spreading Center and East-Pacific Rise crusts [Kyriakopoulos et al., JGR 2015]. This indenter is located as a focus of interseismic locking and coseismic rupture [Feng et al., JGR 2012; Yue et al., JGR 2013; Protti et al., Nat. Geosc. 2014; Xue et al., JGR 2015; Kyriakopoulos & Newman, JGR 2016]. However, aftershocks recorded in the months following an MW 7.6 earthquake in 2012 define an entirely different structure about 5 km deeper and differing only in the area of maximum coseismic slip. The location of seismicity switches entirely between these faults from the shallow indenter structure beforehand to the deeper and near-linear feature after. To improve our imaging of the behavior and associated slab structure, we perform a detailed joint seismic relocation and tomographic inversion using TomoDD [Zhang and Thurber, PAGEOPH 2003]. We analyze the new locations relative to the imaged slab geometry, and compare automated formulations of the interfaces using the Maximum Seismicity Method [Kyriakopoulos et al., 2015], with data existing before and after the earthquake. Lastly, we show the sensitivity of using either surface in models for fault slip from regional GPS. We hypothesize that the bifurcated fault structure signifies either active decapitation of the indenter, possibly along the crust-mantle interface of the downgoing slab

  1. Child Poverty and Family Poverty in OECD Countries

    OpenAIRE

    Forssén, Katja

    1998-01-01

    Childhood in an underdeveloped environment is a stage of life very likely to be overshadowed by poverty. The main aim of this study is to look at the development of child poverty in the comparative angle. The study seeks to detect connections between child poverty and the implemented family policies. Discussion include an overview of family policies in different welfare state models, specification of the goals of the study, report of the results of the empirical analysis, and discussion of th...

  2. Poverty and Human Rights: New Direction in Poverty Eradication

    OpenAIRE

    Buhaerah, Pihri

    2016-01-01

    The purpose of this paper is to support the argument that poverty is multidimensional and part of human rights concern. In doing so, this paper uses relevant literature review on poverty issues. This paper finds that the capability approach is a useful conceptual framework to link conventional approach with human rights and support the argument that poverty is multidimensional. Under this perspective, there are two prerequisites cases of non-fulfillment of human rights can be counted as pover...

  3. Kinematics of subduction and subduction-induced flow in the upper mantle

    NARCIS (Netherlands)

    Schellart, W. P.

    2004-01-01

    Results of fluid dynamical experiments are presented to model the kinematics of lithospheric subduction in the upper mantle. The experiments model a dense highviscosity plate (subducting lithosphere) overlying a less dense low-viscosity layer (upper mantle). The overriding lithosphere is not

  4. Analysis of ray trajectories of flexural waves propagating over generalized acoustic black hole indentations

    Science.gov (United States)

    Huang, Wei; Ji, Hongli; Qiu, Jinhao; Cheng, Li

    2018-03-01

    An Acoustic Black Hole (ABH) indentation embedded in thin-walled structures has been proved remarkably useful for broadband flexural wave focalization, in which the phase velocity of the flexural waves and the refractive index of the media undergo gradual changes from the outside towards the center of the indentation. A generalized two-dimensional ABH indentation can be defined by three geometric parameters: a power index, an extra thickness and a radius of a plateau at the indentation center. The dependence of the energy focalization on these parameters as well as the energy focalization process is of paramount importance for the understanding and design of effective ABH indentations. This work aims at investigating the energy focalization characteristics of flexural waves in such generalized ABH indentations. The calculation of the flexural ray trajectories is conducted to reveal and analyze the wave propagation features through numerical integration of the eikonal equation from the Geometric Acoustics Approximation (GAA). The theoretical results are verified by both experiment using wave visualization technique based on laser acoustic scanning method and finite element (FE) simulations. Finally, the influence of the geometric parameters on the flexural wave focalization characteristics in ABH indentations is discussed in detail.

  5. Indentation versus Rolling: Dependence of Adhesion on Contact Geometry for Biomimetic Structures.

    Science.gov (United States)

    Moyle, Nichole; He, Zhenping; Wu, Haibin; Hui, Chung-Yuen; Jagota, Anand

    2018-04-03

    Numerous biomimetic structures made from elastomeric materials have been developed to produce enhancement in properties such as adhesion, static friction, and sliding friction. As a property, one expects adhesion to be represented by an energy per unit area that is usually sensitive to the combination of shear and normal stresses at the crack front but is otherwise dependent only on the two elastic materials that meet at the interface. More specifically, one would expect that adhesion measured by indentation (a popular and convenient technique) could be used to predict adhesion hysteresis in the more practically important rolling geometry. Previously, a structure with a film-terminated fibrillar geometry exhibited dramatic enhancement of adhesion by a crack-trapping mechanism during indentation with a rigid sphere. Roughly isotropic structures such as the fibrillar geometry show a strong correlation between adhesion enhancement in indentation versus adhesion hysteresis in rolling. However, anisotropic structures, such as a film-terminated ridge-channel geometry, surprisingly show a dramatic divergence between adhesion measured by indentation versus rolling. We study this experimentally and theoretically, first comparing the adhesion of the anisotropic ridge-channel structure to the roughly isotropic fibrillar structure during indentation with a rigid sphere, where only the isotropic structure shows adhesion enhancement. Second, we examine in more detail the anomalous anisotropic film-terminated ridge-channel structure during indentation with a rigid sphere versus rolling to show why these structures show a dramatic adhesion enhancement for the rolling case and no adhesion enhancement for indentation.

  6. Urbanization and Inequality/Poverty

    Directory of Open Access Journals (Sweden)

    Brantley Liddle

    2017-11-01

    Full Text Available The level of world urbanization has crossed the 50% mark, and nearly all future population growth is projected to occur in cities. Cities are disproportionately wealthy, but are associated with poverty, too. Addressing the dual challenges of urbanization and poverty is key to achieving sustainable development. This paper performs cross-sectional regressions, based on Kuznets, as a starting point for understanding the relationship between urbanization and poverty/inequality indicators. Increases in gross domestic product per capita unambiguously lowered poverty and narrowed rural-urban gaps. By contrast, levels of urbanization were either unrelated to poverty/inequality indicators and measures of rural-urban gaps, or had a nonlinear effect where, initially, increases in urbanization likewise led to improvements in those areas, while at higher levels of urbanization, increases in urbanization exacerbated poverty and rural-urban gaps.

  7. Urban Poverty and Gender Issues

    International Nuclear Information System (INIS)

    Mitullah, W.V.

    1999-01-01

    Poverty continues to be a global concern. In Kenya at independence poverty was identified as one of the three main enemies of development; the other two being disease and ignorance. Although there has been deliberate efforts to address disease and ignorance, poverty seem to have overwhelmed the GoK. This is depicted in the fact that 46 per cent of the country's rural population live below poverty line whereas in urban areas incidence of poverty is about 30 per cent. Further Kenya has one of the lowest per-capita incomes in the world and ranks high among world countries that have very high levels of inequality (Kenya and UNICEF, 1992). Overall, 13 million Kenyans have no access to safe water, 6 million have no access to health facilities and 14 million have no access to sanitation (Ikiara and Tostensen, 1995). Many households and individuals are added to the 'poverty space' on daily basis

  8. Climate Change and Poverty Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Simon

    2011-08-15

    Climate change will make it increasingly difficult to achieve and sustain development goals. This is largely because climate effects on poverty remain poorly understood, and poverty reduction strategies do not adequately support climate resilience. Ensuring effective development in the face of climate change requires action on six fronts: investing in a stronger climate and poverty evidence base; applying the learning about development effectiveness to how we address adaptation needs; supporting nationally derived, integrated policies and programmes; including the climate-vulnerable poor in developing strategies; and identifying how mitigation strategies can also reduce poverty and enable adaptation.

  9. Influence of strain gradients on lattice rotation in nano-indentation experiments: A numerical study

    KAUST Repository

    Demiral, Murat

    2014-07-01

    In this paper the texture evolution in nano-indentation experiments was investigated numerically. To achieve this, a three-dimensional implicit finite-element model incorporating a strain-gradient crystal-plasticity theory was developed to represent accurately the deformation of a body-centred cubic metallic material. A hardening model was implemented to account for strain hardening of the involved slip systems. The surface topography around indents in different crystallographic orientations was compared to corresponding lattice rotations. The influence of strain gradients on the prediction of lattice rotations in nano-indentation was critically assessed. © 2014 Elsevier B.V..

  10. Comment on 'Axisymmetric indentation of an incompressible elastic thin film'

    Energy Technology Data Exchange (ETDEWEB)

    Chadwick, Richard S [Section on Auditory Mechanics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892 (United States)

    2005-04-07

    It is shown that a recent method based on the asymptotic inversion of Hankel transforms for indentation of thin films (Yang F Q 2003 J. Phys. D: Appl. Phys. 36 50) provides a non-unique solution for the case of frictionless contact between the film and the substrate. In addition to the solution given by Yang, another one exists having zero hydrostatic stress that results in half the force acting on the indenter for the same indentation. A more rigorous asymptotic method (Chadwick R S 2002 SIAM J. Appl. Math. 62 1520) singles out the smaller force solution as the correct one. (comment)

  11. Protected areas and poverty.

    Science.gov (United States)

    Brockington, Daniel; Wilkie, David

    2015-11-05

    Protected areas are controversial because they are so important for conservation and because they distribute fortune and misfortune unevenly. The nature of that distribution, as well as the terrain of protected areas themselves, have been vigorously contested. In particular, the relationship between protected areas and poverty is a long-running debate in academic and policy circles. We review the origins of this debate and chart its key moments. We then outline the continuing flashpoints and ways in which further evaluation studies could improve the evidence base for policy-making and conservation practice. © 2015 The Authors.

  12. Poverty reduction in Africa.

    Science.gov (United States)

    Collier, Paul

    2007-10-23

    Poverty in Africa has been rising for the last quarter-century, while it has been falling in the rest of the developing world. Africa's distinctive problem is that its economies have not been growing. This article attempts to synthesize a range of recent research to account for this failure of the growth process. I argue that the reasons lie not in African peculiarities but rather in geographic features that globally cause problems but that are disproportionately pronounced in Africa. These features interact to create three distinct challenges that are likely to require international interventions beyond the conventional reliance on aid.

  13. An International Inquiry: Stories of Poverty--Poverty Stories

    Science.gov (United States)

    Ciuffetelli Parker, Darlene; Craig, Cheryl J.

    2017-01-01

    This article features an international inquiry of two high-poverty urban schools, one Canadian and one American. The article examines poverty in terms of "small stories" that educators and students live and tell, often on the edges, unheard and unaccounted for in grand narratives. It also expands the story constellations approach to…

  14. Elite perceptions of poverty and Nigeria's poverty reduction research ...

    African Journals Online (AJOL)

    The way the elite perceive poverty and the poor in any society constitutes a very important dimension of poverty research. This is because normally there are several areas of interrelationship and interdependence between the poor and the elite, and these form part of the basis for social life in all societies. Perceptions of the ...

  15. Brain Drain: A Child's Brain on Poverty. Poverty Fact Sheet

    Science.gov (United States)

    Damron, Neil

    2015-01-01

    "Brain Drain: A Child's Brain on Poverty," released in March 2015 and prepared by intern Neil Damron, explores the brain's basic anatomy and recent research findings suggesting that poverty affects the brain development of infants and young children and the potential lifelong effects of the changes. The sheet draws from a variety of…

  16. Poverty and Poverty Status in Oil Producing Communities of Ondo ...

    African Journals Online (AJOL)

    This paper examined poverty and poverty status in the oil producing communities of Nigeria; using oil-producing communities of Ondo state, Nigeria as a case study. Multi-stage sampling technique was used to collect data on economic characteristics of the household. In the first stage, oil-producing communities were ...

  17. The Literature of Poverty, the Poverty of Literature Classes

    Science.gov (United States)

    Marsh, John

    2011-01-01

    In this article, the author focuses on the possibilities--and the limits--of undergraduate courses on the literature of poverty. He describes an undergraduate course he has taught on U.S. literature about poverty, but he also expresses doubt that such courses can help produce major social change. He argues that something about the literature of…

  18. Indentation size effects in the nano- and micro-hardness of a Fe-based bulk metallic glass

    Energy Technology Data Exchange (ETDEWEB)

    Xu, F., E-mail: xufu@xtu.edu.cn; Ding, Y.H.; Deng, X.H.; Zhang, P.; Long, Z.L.

    2014-10-01

    Hardness of a Fe-based bulk metallic glass (BMG) was evaluated by both atomic force microscopy (AFM) nanoindentation (nano-hardness) and instrumented indentation with a traditional indenter setup (micro-hardness) under different maximum loads at room temperature. The nano-hardness and the micro-hardness were found to be comparable. For both of the indentation methods, indentation size effect (ISE) is detected as increase in hardness with decrease in indentation peak load. It is proposed that strain rate dependent softening, loading history and the lag between free volume creation and mechanical softening should be responsible for the ISE in this BMG. Furthermore, ISE is found to be more significant in AFM nanoindentation than in instrumented indentation. This can be explained by taking into account the effect of exerted peak load and the face angle of the indenter in a qualitative manner.

  19. [Population trends and poverty].

    Science.gov (United States)

    Olmedo, C

    1998-04-01

    Implications of population growth in Ecuador for the quality of life of the poor population are analyzed. It is argued that if the gross national product (GNP) were to grow at a sustained annual rate of 5% or more, demographic trends would not present a significant obstacle to reducing poverty. National economic projections are for growth of only 2.5-3.5% annually. The continuing rapid growth of the poor population despite general slowing of demographic growth, the young age structure, the need for increased formal education to enable the poor to overcome their poverty, and the effect of unemployment on the dependency ratio will tend to hamper improvements in average productivity and per capita GNP. The need for spending on education, health, basic services, and housing will divert funds away from productive investment, generating a direct negative impact on economic growth. Over half of Ecuadorian children suffer from some degree of malnutrition, indicating that food production is inadequate to meet demand. The export-oriented agricultural policy and poor weather have led to a chronic shortage of basic foods. Progressive increase and diversification of agricultural production, along with maintenance of low prices and substantial increases in income levels and agricultural productivity, will be required if the entire population is to be fed adequately. Intense efforts will be needed from all sectors to bring demographic growth into balance with economic and development needs.

  20. Plastic Indentation Analysis Used in Study of Colliding Robotic Elements

    Directory of Open Access Journals (Sweden)

    Florina Carmen Ciornei

    2014-06-01

    Full Text Available In robotic system there are frequent situations when on the robotic parts percutions develop. The impact plastic imprints are unique source of data remaining after collision, but complications occur in the analysis and the work models a general impact and presents the manner of processing the experimental data. The paper presents the characteristics occurring in the analysis of the indentation remnant after the oblique impact between a free falling ball and the surface of an inclined metallic prism. A series of difficulties arise while trying to approximate the collision’s imprint profile with a parabola having oblique symmetry axis. Both these impediments and the manner of surmounting them are presented. Finally, the impasse that takes place in the actual analysis of an imprint profile is presented. A first method of surpassing this aspect uses the intrinsic characteristics of osculating circle in a point of the profile is applicable only for smooth signals. The second proposed method is applied to the real signal and provides fine results.

  1. Determination of the Mechanical Properties of Plasma-Sprayed Hydroxyapatite Coatings Using the Knoop Indentation Technique

    Science.gov (United States)

    Hasan, Md. Fahad; Wang, James; Berndt, Christopher

    2015-06-01

    The microhardness and elastic modulus of plasma-sprayed hydroxyapatite coatings were evaluated using Knoop indentation on the cross section and on the top surface. The effects of indentation angle, testing direction, measurement location and applied load on the microhardness and elastic modulus were investigated. The variability and distribution of the microhardness and elastic modulus data were statistically analysed using the Weibull modulus distribution. The results indicate that the dependence of microhardness and elastic modulus on the indentation angle exhibits a parabolic shape. Dependence of the microhardness values on the indentation angle follows Pythagoras's theorem. The microhardness, Weibull modulus of microhardness and Weibull modulus of elastic modulus reach their maximum at the central position (175 µm) on the cross section of the coatings. The Weibull modulus of microhardness revealed similar values throughout the thickness, and the Weibull modulus of elastic modulus shows higher values on the top surface compared to the cross section.

  2. Finite Element Bond Modeling for Indented Wires in Pretensioned Concrete Crossties

    Science.gov (United States)

    2016-04-12

    Indented wires have been increasingly employed by : concrete crosstie manufacturers to improve the bond between : prestressing steel reinforcements and concrete, as bond can : affect several critical performance measures, including transfer : length,...

  3. Experimental validation of the new modular application of the upper bound theorem in indentation.

    Directory of Open Access Journals (Sweden)

    Carolina Bermudo

    Full Text Available Nowadays, thanks to the new manufacturing processes, indentation is becoming an essential part of the new arising processes such as the Incremental Forming Processes. This work presents the experimental validation of the analytical model developed for an indentation-based process. The analytical model is originated from the Upper Bound Theorem application by means of its new modular distribution. The modules considered are composed of two Triangular Rigid Zones each. The experimental validation is performed through a series of indentation tests with work-pieces of annealed aluminium EN AW-2030 and punches of steel AISI 304, under plane strain conditions. The results are compared with the ones obtained from the application of this new modular distribution of the Upper Bound Theorem, showing a good approximation and suitability of the model developed for an indentation-based process.

  4. Experimental Validation of the New Modular Application of the Upper Bound Theorem in Indentation

    Science.gov (United States)

    Bermudo, Carolina; Martín, Francisco; Martín, María Jesús; Sevilla, Lorenzo

    2015-01-01

    Nowadays, thanks to the new manufacturing processes, indentation is becoming an essential part of the new arising processes such as the Incremental Forming Processes. This work presents the experimental validation of the analytical model developed for an indentation-based process. The analytical model is originated from the Upper Bound Theorem application by means of its new modular distribution. The modules considered are composed of two Triangular Rigid Zones each. The experimental validation is performed through a series of indentation tests with work-pieces of annealed aluminium EN AW-2030 and punches of steel AISI 304, under plane strain conditions. The results are compared with the ones obtained from the application of this new modular distribution of the Upper Bound Theorem, showing a good approximation and suitability of the model developed for an indentation-based process. PMID:25826738

  5. Aqueous humour dynamics in anterior chamber under influence of cornea indentation

    Science.gov (United States)

    Zuhaila, I.; Jiann, L. Y.; Sharidan, S.; Fitt, A.

    2017-04-01

    The existing temperature different between the cornea and the pupil induces the aqueous humour (AH) to circulate in the anterior chamber (AC). The buoyancy forces produced by the temperature gradient has driven the AH to flow. Previous studies have shown that cornea indentation changes the structure of the AC. This imply that the cornea indentation may change the fluid flow behaviour in the AC. A mathematical model of AH flow has been developed in order to analyse the fluid mechanics concerning the indentation of the cornea. Naiver-Stokes equations is used to describe the flow of AH in the AC. The governing equations have been solved numerically using finite element method. The results show that the cornea indentation has slow down the circulation the AH in the AC.

  6. Spherical indentation of a freestanding circular membrane revisited: Analytical solutions and experiments

    Science.gov (United States)

    Jin, Congrui; Davoodabadi, Ali; Li, Jianlin; Wang, Yanli; Singler, Timothy

    2017-03-01

    Due to the development of novel micro-fabrication techniques to produce ultra-thin materials and increasing interest in thin biological membranes, in recent years, the mechanical characterization of thin films has received a significant amount of attention. To provide a more accurate solution for the relationship among contact radius, load and deflection, the fundamental and widely applicable problem of spherical indentation of a freestanding circular membrane have been revisited. The work presented here significantly extends the previous contributions by providing an exact analytical solution to the governing equations of Föppl-Hecky membrane indented by a frictionless spherical indenter. In this study, experiments of spherical indentation has been performed, and the exact analytical solution presented in this paper is compared against experimental data from existing literature as well as our own experimental results.

  7. Experimental validation of the new modular application of the upper bound theorem in indentation.

    Science.gov (United States)

    Bermudo, Carolina; Martín, Francisco; Martín, María Jesús; Sevilla, Lorenzo

    2015-01-01

    Nowadays, thanks to the new manufacturing processes, indentation is becoming an essential part of the new arising processes such as the Incremental Forming Processes. This work presents the experimental validation of the analytical model developed for an indentation-based process. The analytical model is originated from the Upper Bound Theorem application by means of its new modular distribution. The modules considered are composed of two Triangular Rigid Zones each. The experimental validation is performed through a series of indentation tests with work-pieces of annealed aluminium EN AW-2030 and punches of steel AISI 304, under plane strain conditions. The results are compared with the ones obtained from the application of this new modular distribution of the Upper Bound Theorem, showing a good approximation and suitability of the model developed for an indentation-based process.

  8. Flat indentation of a viscoelastic polymer film on a rigid substrate

    International Nuclear Information System (INIS)

    Choi, Seung Tae; Lee, Seung Ryoon; Earmme, Youn Young

    2008-01-01

    A systematic method of flat indentation was developed to measure the elastic and viscoelastic properties of polymer films. A flat indentation problem on an elastic film perfectly bonded to a rigid substrate was revisited, from which the relationship between the applied force and the penetration depth was obtained in a simple form. Application of the elastic-viscoelastic correspondence principle converts the force-depth relationship for elastic films to the Laplace transform of that for viscoelastic films. Indentation experiments with a flat diamond tip were performed on polymer films (SU-8 and NR4-8000P). Analysis of the measured data with the viscoelastic force-depth relationship provides the shear moduli, Poisson's ratios, and relaxation moduli of these films. Viscoplastic deformations produced in the films that underwent the flat indentation process were quantified by measuring the residual deformation after unloading with an atomic force microscope

  9. Simplifying the Water Poverty Index

    Science.gov (United States)

    Cho, Danny I.; Ogwang, Tomson; Opio, Christopher

    2010-01-01

    In this paper, principal components methodology is used to derive simplified and cost effective indexes of water poverty. Using a well known data set for 147 countries from which an earlier five-component water poverty index comprising of "Resources," "Access," "Capacity," "Use" and "Environment" was constructed, we find that a simplified…

  10. The elusive constellations of poverty.

    Science.gov (United States)

    Breugelmans, Seger M; Plantinga, Arnoud; Zeelenberg, Marcel; Poluektova, Olga; Efremova, Maria

    2017-01-01

    Pepper & Nettle describe possible processes underlying what they call a behavioral constellation of deprivation (BCD). Although we are certain about the application of evolutionary models to our understanding of poverty, we are less certain about the utility of behavioral constellations. The empirical record on poverty-related behaviors is much more divergent and broad than such constellations suggest.

  11. Exposure to Poverty and Productivity

    NARCIS (Netherlands)

    Dalton, Patricio; Gonzalez Jimenez, Victor; Noussair, Charles

    2016-01-01

    We study whether poverty can induce affective states that decrease productivity. In a controlled laboratory setting, we find that subjects randomly assigned to a treatment, in which they view a video featuring individuals that live in extreme poverty, exhibit lower subsequent productivity compared

  12. Measuring energy poverty in Greece

    International Nuclear Information System (INIS)

    Papada, Lefkothea; Kaliampakos, Dimitris

    2016-01-01

    A comprehensive research in the field of energy poverty is undertaken in this paper, in an attempt to highlight the great vulnerability of Greek households on energy poverty, in the middle of a severe economic crisis. Till now, Greek energy policy has been considered insufficient to tackle energy poverty issues, as focusing mainly on short-term rather than permanent solutions. A primary survey has been conducted, recording objective data of energy expenses as well as subjective perceptions about housing conditions. The findings showed that, under the objective expenditure-based method, 58% of Greek households are energy poor. Among households under the poverty threshold, the energy poverty rate exceeds 90%. Existing and new subjective indicators shed light on other aspects of energy poverty, such as the level of thermal comfort at home, damp problems detected, restriction of other essential needs in order to manage energy payments, etc. Some interesting conclusions are also drawn by exploring the relationship between various indicators. It appears that households considered energy poor are not identical when examined by objective and subjective indicators. However, different indicators complement each other by capturing different aspects of the problem and provide a broader overview of the issue. - Highlights: •58% of Greek households are energy poor. •75% of Greek households have reduced other essentials in favor of energy needs. •Combination of objective and subjective indicators captures better energy poverty. •Greek energy policy has failed to tackle energy poverty issues.

  13. Defining poverty as distinctively human

    African Journals Online (AJOL)

    p1243322

    eradicate poverty. 117 heads of state or government attended the World. Summit for Social Development in 1995. At that event the “largest gathering yet of world ..... ostracized or marginalized for whatever reason – as poor people often are – ..... kind of poverty that causes social exclusion only be defined in terms of the.

  14. Climate Change, Growth, and Poverty

    OpenAIRE

    Hull, Katy

    2008-01-01

    Equity emerged as the principal theme during the Poverty Reduction and Economic Management (PREM) week session 'climate change, growth and poverty,' where presenters addressed the distributional consequences of climate change, as well as countries' unequal capacity to cope with the twin challenges of adaptation and mitigation. They highlighted actions to strengthen the global knowledge bas...

  15. Gender, poverty and social justice

    NARCIS (Netherlands)

    A. Chhachhi (Amrita); T-D. Truong (Thanh-Dam)

    2009-01-01

    textabstractViews on poverty are deeply rooted in cultural frameworks about the human condition shaped by histories. In the debate on modernity, perspectives on poverty oscillate between: a) making the poor -- their "morals" and "culture" -- responsible for their own situation and b) positioning the

  16. Measuring Chronic Non-Income Poverty

    OpenAIRE

    Klasen, Stephan; Günther, Isabel

    2007-01-01

    An increasing interest in poverty dynamics has lately also led to an extensive literature on the analysis of chronic poverty. Based on Amartya Sen?s groundbreaking work on capabilities and functionings static poverty measures have long used non-income indicators. In contrast, measures of poverty dynamics - including chronic poverty – have in general conceptualised poverty only in an income dimension. Hence, this paper first critically discusses the conceptual and empirical potentials and limi...

  17. Income and wealth poverty in Germany

    OpenAIRE

    Köhler, Theresa

    2016-01-01

    In general, poverty measures are estimated by applying income information. However, only using income data for calculating relative poverty might lead to an incomplete view. For example, a household can be under a poverty threshold even if a household member owns real estate or equity. In this thesis, at risk of income poverty in Germany is estimated. In order to get a more complete picture of at risk of poverty, a multidimensional approach is applied. Not only at risk of income poverty, also...

  18. Should poverty researchers worry about inequality?

    OpenAIRE

    Armando Barrientos

    2010-01-01

    The paper constructs a case for arguing that poverty researchers need not worry about inequality (as poverty researchers). It reviews conceptualisations of poverty as essentially relational, a particular reflection of prevailing inequalities. In this approach, people are in poverty because they are less well off than others along important dimensions of wellbeing. As against this view, the paper constructs a case for studying poverty as non-relational. In this approach, people are in poverty ...

  19. Exposure to Poverty and Productivity

    Science.gov (United States)

    2017-01-01

    We study whether exposure to poverty can induce affective states that decrease productivity. In a controlled laboratory setting, we find that subjects randomly assigned to a treatment, in which they view a video featuring individuals that live in extreme poverty, exhibit lower subsequent productivity compared to subjects assigned to a control treatment. Questionnaire responses, as well as facial recognition software, provide quantitative measures of the affective state evoked by the two treatments. Subjects exposed to images of poverty experience a more negative affective state than those in the control treatment. Further analysis shows that individuals in a more positive emotional state exhibit less of a treatment effect. Also, those who exhibit greater attentiveness upon viewing the poverty video are less productive. The results are consistent with the notion that exposure to poverty can induce a psychological state in individuals that adversely affects productivity. PMID:28125621

  20. Exposure to Poverty and Productivity.

    Directory of Open Access Journals (Sweden)

    Patricio S Dalton

    Full Text Available We study whether exposure to poverty can induce affective states that decrease productivity. In a controlled laboratory setting, we find that subjects randomly assigned to a treatment, in which they view a video featuring individuals that live in extreme poverty, exhibit lower subsequent productivity compared to subjects assigned to a control treatment. Questionnaire responses, as well as facial recognition software, provide quantitative measures of the affective state evoked by the two treatments. Subjects exposed to images of poverty experience a more negative affective state than those in the control treatment. Further analysis shows that individuals in a more positive emotional state exhibit less of a treatment effect. Also, those who exhibit greater attentiveness upon viewing the poverty video are less productive. The results are consistent with the notion that exposure to poverty can induce a psychological state in individuals that adversely affects productivity.

  1. Puncture mechanics of soft elastomeric membrane with large deformation by rigid cylindrical indenter

    Science.gov (United States)

    Liu, Junjie; Chen, Zhe; Liang, Xueya; Huang, Xiaoqiang; Mao, Guoyong; Hong, Wei; Yu, Honghui; Qu, Shaoxing

    2018-03-01

    Soft elastomeric membrane structures are widely used and commonly found in engineering and biological applications. Puncture is one of the primary failure modes of soft elastomeric membrane at large deformation when indented by rigid objects. In order to investigate the puncture failure mechanism of soft elastomeric membrane with large deformation, we study the deformation and puncture failure of silicone rubber membrane that results from the continuous axisymmetric indentation by cylindrical steel indenters experimentally and analytically. In the experiment, effects of indenter size and the friction between the indenter and the membrane on the deformation and puncture failure of the membrane are investigated. In the analytical study, a model within the framework of nonlinear field theory is developed to describe the large local deformation around the punctured area, as well as to predict the puncture failure of the membrane. The deformed membrane is divided into three parts and the friction contact between the membrane and indenter is modeled by Coulomb friction law. The first invariant of the right Cauchy-Green deformation tensor I1 is adopted to predict the puncture failure of the membrane. The experimental and analytical results agree well. This work provides a guideline in designing reliable soft devices featured with membrane structures, which are present in a wide variety of applications.

  2. Technical and practical improvements in arthroscopic indentation technique for diagnostics of articular cartilage softening.

    Science.gov (United States)

    Timonen, M A; Töyräs, J; Aula, A S; Karjalainen, J P; Riekkinen, O; Jurvelin, J S

    2011-01-01

    Indentation measurements have been proposed to serve as sensitive in vivo diagnostics of cartilage degeneration. However, practical difficulties have hindered the use of quantitative indentation techniques during routine arthroscopies. In this study we modified the previously commercial indentation technique by designing software for quality control of manual indentations. With the modifications, our aim was to introduce more rapid and less erroneous measurements, as well as more automatic and objective analyses. The performance of the technique was tested in situ using six bovine medial tibial plateaus. All measurements were conducted by three operators. The intraoperator reproducibility was reasonable (CV%  = 7.1%) and the interoperator reproducibility was good (intraclass correlation coefficient  = 0.976). Further, the novel technique was tested by a single operator using 10 bovine medial tibial plateaus. The indentation stiffness values determined with the arthroscopic instrument correlated significantly with the dynamic (r = 0.823) and equilibrium (r = 0.752) moduli as well as tissue water (r =  -0.830) and hydroxyproline (r = 0.776) contents. To conclude, the novel measurement technique showed good reproducibility and was found to give valuable information on cartilage properties. Most importantly, the measurements and analyses were more straightforward and automatic than those introduced in the original indentation approach.

  3. Indentation Size Effect on Ag Nanoparticle-Modified Graphene/Sn-Ag-Cu Solders

    Science.gov (United States)

    Xu, L. Y.; Zhang, S. T.; Jing, H. Y.; Wang, L. X.; Wei, J.; Kong, X. C.; Han, Y. D.

    2018-01-01

    This paper presents the results for the indentation size effect (ISE) on the creep stress exponent and hardness of 0.03 wt.% Ag-modified graphene nanosheet Sn-Ag-Cu solder alloys, using constant loading/holding and multi-cycle (CMC) loading methods, respectively. At each maximum load, with increasing indentation depth, the creep exponent first decreased and then increased. At the same strain rate, the stress exponent also showed the same tendency, increasing as the indentation depth (peak load) increased and then decreased. The hardness was measured continuously with increasing indentation depth by the CMC loading method. The hardness did not exhibit a decrease as the indentation depth increased, which differs from the classical description of the ISE. After an initial decrease, the hardness then increased and finally decreased as the indentation depth increased. This study reviews the existing theories and formulations describing ISE with hardening effects. The experimental results fit well with the empirical formulation. The phenomenon of ISE accompanied by hardening effects has been explained physically via the interaction between geometrically necessary dislocations and grain boundaries.

  4. Quasi-Plastic Deformation of WC-Co Composites Loaded with a Spherical Indenter

    Science.gov (United States)

    Zhang, Haibo; Fang, Zhigang Zak; Belnap, J. Daniel

    2007-03-01

    The quasi-plastic deformation behavior of cemented tungsten carbide (WC-Co) materials was studied using Hertzian indentation techniques. The indentation stress-strain curves of three WC-10 wt pct Co alloys with different hardness values demonstrate that WC-Co alloys exhibit “quasi-plasticity” behavior under indentation load and the increase of indentation stress vs indentation strain bears similarity to “strain hardening” in ductile metals. The analysis of the subsurface indentation damage shows that the mechanisms of the quasi-plastic deformation of WC-Co material are the formation of microcracks. Microcracks were found at heavily damaged areas in all three alloys, and the number of microcracks was higher for the sample with the higher apparent quasi-plasticity. The threshold stress values for the onset of quasi-plastic deformation and formation of ring cracks were determined and used to evaluate the brittleness index of these materials. The correlation of the brittleness index with hardness values gives insight with regard to the brittle or quasi-plastic responses of WC-Co materials.

  5. Method to determine the optimal constitutive model from spherical indentation tests

    Directory of Open Access Journals (Sweden)

    Tairui Zhang

    2018-03-01

    Full Text Available The limitation of current indentation theories was investigated and a method to determine the optimal constitutive model through spherical indentation tests was proposed. Two constitutive models, the Power-law and the Linear-law, were used in Finite Element (FE calculations, and then a set of indentation governing equations was established for each model. The load-depth data from the normal indentation depth was used to fit the best parameters in each constitutive model while the data from the further loading part was compared with those from FE calculations, and the model that better predicted the further deformation was considered the optimal one. Moreover, a Yang’s modulus calculation model which took the previous plastic deformation and the phenomenon of pile-up (or sink-in into consideration was also proposed to revise the original Sneddon-Pharr-Oliver model. The indentation results on six materials, 304, 321, SA508, SA533, 15CrMoR, and Fv520B, were compared with tensile ones, which validated the reliability of the revised E calculation model and the optimal constitutive model determination method in this study. Keywords: Optimal constitutive model, Spherical indentation test, Finite Element calculations, Yang’s modulus

  6. Influence of the subducting plate velocity on the geometry of the slab and migration of the subduction hinge

    NARCIS (Netherlands)

    Schellart, Wouter P.

    2005-01-01

    Geological observations indicate that along two active continental margins (East Asia and Mediterranean) major phases of overriding plate extension, resulting from subduction hinge-retreat, occurred synchronously with a reduction in subducting plate velocity. In this paper, results of fluid

  7. Stress orientations in subduction zones and the strength of subduction megathrust faults.

    Science.gov (United States)

    Hardebeck, Jeanne L

    2015-09-11

    Subduction zone megathrust faults produce most of the world's largest earthquakes. Although the physical properties of these faults are difficult to observe directly, their frictional strength can be estimated indirectly by constraining the orientations of the stresses that act on them. A global investigation of stress orientations in subduction zones finds that the maximum compressive stress axis plunges systematically trenchward, consistently making an angle of 45° to 60° with respect to the subduction megathrust fault. These angles indicate that the megathrust fault is not substantially weaker than its surroundings. Together with several other lines of evidence, this implies that subduction zone megathrusts are weak faults in a low-stress environment. The deforming outer accretionary wedge may decouple the stress state along the megathrust from the constraints of the free surface. Copyright © 2015, American Association for the Advancement of Science.

  8. Inequality, Poverty, Insecurity

    Directory of Open Access Journals (Sweden)

    Ilona

    2015-04-01

    Full Text Available The article discusses the economic connections of globalization, the roots of this phenomenon and its implications for presence. In the 70´, the economic bases of developed countries started changing. Since then the economic power of transnational corporations has risen. The TNCs change the international division of labor and divide the production cycle in an unprecedented manner. The economic sovereignty of countries weakens. All these factors influence the position of labor and consequently phenomena like unemployment, poverty and uncertainty. Since the 70´s the wage share, one of the most important macroeconomic indicators, has started sinking in developed contries. This means that a higher proportion of output goes to capital, i.e. to profits. Unemployment in developed countries has also changed its form since the 70´s – it has become structural and long-term one. Forms of precarious labor increase significantly and in the developed countries (especially obviously in the US the phenomenon of working poverty appears. Hand in hand with these phenomena goes the increase in inequality, of all developed countries again mostly in the US. The implications are not only social, such as the preservation of elite, i.e. the tendency towards oligarchization and decrease in social mobility. These implications are also connected with the debt phenomenon, which serves as a factor of discipline and system preservation, or respectively the postponement of weakened purchasing power of the lower and middle income classes. The rise in insecurity and the impossibility to identify oneself with the job has its political implications as well. In the context of reflecting the problem itself it takes form of various social protests (such as Occupy Wall Street, but also can be shown in the rise of various xenophobe and extreme right movements that destabilize the whole political system, including doubting the regime of democracy as such.

  9. Vaccines against poverty

    Science.gov (United States)

    MacLennan, Calman A.; Saul, Allan

    2014-01-01

    With the 2010s declared the Decade of Vaccines, and Millennium Development Goals 4 and 5 focused on reducing diseases that are potentially vaccine preventable, now is an exciting time for vaccines against poverty, that is, vaccines against diseases that disproportionately affect low- and middle-income countries (LMICs). The Global Burden of Disease Study 2010 has helped better understand which vaccines are most needed. In 2012, US$1.3 billion was spent on research and development for new vaccines for neglected infectious diseases. However, the majority of this went to three diseases: HIV/AIDS, malaria, and tuberculosis, and not neglected diseases. Much of it went to basic research rather than development, with an ongoing decline in funding for product development partnerships. Further investment in vaccines against diarrheal diseases, hepatitis C, and group A Streptococcus could lead to a major health impact in LMICs, along with vaccines to prevent sepsis, particularly among mothers and neonates. The Advanced Market Commitment strategy of the Global Alliance for Vaccines and Immunisation (GAVI) Alliance is helping to implement vaccines against rotavirus and pneumococcus in LMICs, and the roll out of the MenAfriVac meningococcal A vaccine in the African Meningitis Belt represents a paradigm shift in vaccines against poverty: the development of a vaccine primarily targeted at LMICs. Global health vaccine institutes and increasing capacity of vaccine manufacturers in emerging economies are helping drive forward new vaccines for LMICs. Above all, partnership is needed between those developing and manufacturing LMIC vaccines and the scientists, health care professionals, and policy makers in LMICs where such vaccines will be implemented. PMID:25136089

  10. Evaluation of sinking-in and cracking behavior of soda-lime glass under varying angle of trigonal pyramid indenter

    Directory of Open Access Journals (Sweden)

    Satoshi Yoshida

    2016-12-01

    Full Text Available It is well known that glass undergoes elastic and inelastic deformation under a sharp diamond indenter. Although brittle or less-brittle behavior of glass must be connected with such mechanical responses of glass under the indenter, there has been limited research on in-situ deformation behavior of glass during the loading and unloading indentation cycle. This is because most indentation tests were conducted using a commercial hardness tester for which this information is not available. In this study, the in-situ sinking-in region of glass during indentation test is determined using a custom-designed indentation microscope with trigonal pyramid indenters having different tip angles. It is found that both the shape of contact region and the amount of sinking-in are affected by indenter geometries, and that the projected contact region of the glass sample under Berkovich indenter is not a regular triangle, but a concave triangle with bowed-in edges. This is due to the larger amount of sinking-in under the face than under the ridge of indenter. It is also found that these deformation behaviors of glass are inseparably linked with contact damage or cracking in glass.

  11. Dynamics of intraoceanic subduction initiation : 1. Oceanic detachment fault inversion and the formation of supra-subduction zone ophiolites

    NARCIS (Netherlands)

    Maffione, Marco; Thieulot, Cedric; van Hinsbergen, Douwe J.J.; Morris, Antony; Plümper, Oliver; Spakman, Wim

    Subduction initiation is a critical link in the plate tectonic cycle. Intraoceanic subduction zones can form along transform faults and fracture zones, but how subduction nucleates parallel to mid-ocean ridges, as in e.g., the Neotethys Ocean during the Jurassic, remains a matter of debate. In

  12. Global correlations between maximum magnitudes of subduction zone interface thrust earthquakes and physical parameters of subduction zones

    NARCIS (Netherlands)

    Schellart, W. P.; Rawlinson, N.

    2013-01-01

    The maximum earthquake magnitude recorded for subduction zone plate boundaries varies considerably on Earth, with some subduction zone segments producing giant subduction zone thrust earthquakes (e.g. Chile, Alaska, Sumatra-Andaman, Japan) and others producing relatively small earthquakes (e.g.

  13. Alternate approach for calculating hardness based on residual indentation depth: Comparison with experiments

    Science.gov (United States)

    Ananthakrishna, G.; K, Srikanth

    2018-03-01

    It is well known that plastic deformation is a highly nonlinear dissipative irreversible phenomenon of considerable complexity. As a consequence, little progress has been made in modeling some well-known size-dependent properties of plastic deformation, for instance, calculating hardness as a function of indentation depth independently. Here, we devise a method of calculating hardness by calculating the residual indentation depth and then calculate the hardness as the ratio of the load to the residual imprint area. Recognizing the fact that dislocations are the basic defects controlling the plastic component of the indentation depth, we set up a system of coupled nonlinear time evolution equations for the mobile, forest, and geometrically necessary dislocation densities. Within our approach, we consider the geometrically necessary dislocations to be immobile since they contribute to additional hardness. The model includes dislocation multiplication, storage, and recovery mechanisms. The growth of the geometrically necessary dislocation density is controlled by the number of loops that can be activated under the contact area and the mean strain gradient. The equations are then coupled to the load rate equation. Our approach has the ability to adopt experimental parameters such as the indentation rates, the geometrical parameters defining the Berkovich indenter, including the nominal tip radius. The residual indentation depth is obtained by integrating the Orowan expression for the plastic strain rate, which is then used to calculate the hardness. Consistent with the experimental observations, the increasing hardness with decreasing indentation depth in our model arises from limited dislocation sources at small indentation depths and therefore avoids divergence in the limit of small depths reported in the Nix-Gao model. We demonstrate that for a range of parameter values that physically represent different materials, the model predicts the three characteristic

  14. Mechanical characterization of soft materials using transparent indenter testing system and finite element simulation

    Science.gov (United States)

    Xuan, Yue

    Background. Soft materials such as polymers and soft tissues have diverse applications in bioengineering, medical care, and industry. Quantitative mechanical characterization of soft materials at multiscales is required to assure that appropriate mechanical properties are presented to support the normal material function. Indentation test has been widely used to characterize soft material. However, the measurement of in situ contact area is always difficult. Method of Approach. A transparent indenter method was introduced to characterize the nonlinear behaviors of soft materials under large deformation. This approach made the direct measurement of contact area and local deformation possible. A microscope was used to capture the contact area evolution as well as the surface deformation. Based on this transparent indenter method, a novel transparent indentation measurement systems has been built and multiple soft materials including polymers and pericardial tissue have been characterized. Seven different indenters have been used to study the strain distribution on the contact surface, inner layer and vertical layer. Finite element models have been built to simulate the hyperelastic and anisotropic material behaviors. Proper material constants were obtained by fitting the experimental results. Results.Homogeneous and anisotropic silicone rubber and porcine pericardial tissue have been examined. Contact area and local deformation were measured by real time imaging the contact interface. The experimental results were compared with the predictions from the Hertzian equations. The accurate measurement of contact area results in more reliable Young's modulus, which is critical for soft materials. For the fiber reinforced anisotropic silicone rubber, the projected contact area under a hemispherical indenter exhibited elliptical shape. The local surface deformation under indenter was mapped using digital image correlation program. Punch test has been applied to thin films of

  15. Poverty eradication: a new paradigm.

    Science.gov (United States)

    Pethe, V P

    1998-08-01

    This article offers a new paradigm for eradicating poverty in India. It was assumed incorrectly by Mahatma Gandhi that a good society without mass poverty would follow after independence. India copied Western models of development and developed giant factories, big dams, and megacities. Agriculture did not expand the number of jobs for people. The Western paradigm failed in India because of the false assumption of "trickle down" of income to the masses. The targeted programs to the poor did not directly benefit enough of the poor. Mega-industrialization led to reduced employment and higher skill needs. The model failed mainly because it was a proxy and relied on indirect ways of reaching the poor. The models failed to be adapted to conditions in India. The Swadeshi paradigm is a direct model for addressing mass poverty. Poverty is affected by immediate, intermediate, and ultimate determinants. Poverty begets social and economic problems, such as ignorance, ill health, high fertility, unemployment, and crime. In India and developing countries, mass poverty results from under use of human resources; lack of equal opportunities; and an outdated non-egalitarian social structure, an unjust global economic order, human cruelty, and erosion of ethical values. Indians are squandering their precious resources mimicking Western consumerism. Poverty leads to rapid population growth. People become productive assets with universal literacy, compulsory and free education, health services and sanitation, vocational training, and work ethics. India needs people-oriented policies with less emphasis on capital accumulation.

  16. Mantle flow influence on subduction evolution

    Science.gov (United States)

    Chertova, Maria V.; Spakman, Wim; Steinberger, Bernhard

    2018-05-01

    The impact of remotely forced mantle flow on regional subduction evolution is largely unexplored. Here we investigate this by means of 3D thermo-mechanical numerical modeling using a regional modeling domain. We start with simplified models consisting of a 600 km (or 1400 km) wide subducting plate surrounded by other plates. Mantle inflow of ∼3 cm/yr is prescribed during 25 Myr of slab evolution on a subset of the domain boundaries while the other side boundaries are open. Our experiments show that the influence of imposed mantle flow on subduction evolution is the least for trench-perpendicular mantle inflow from either the back or front of the slab leading to 10-50 km changes in slab morphology and trench position while no strong slab dip changes were observed, as compared to a reference model with no imposed mantle inflow. In experiments with trench-oblique mantle inflow we notice larger effects of slab bending and slab translation of the order of 100-200 km. Lastly, we investigate how subduction in the western Mediterranean region is influenced by remotely excited mantle flow that is computed by back-advection of a temperature and density model scaled from a global seismic tomography model. After 35 Myr of subduction evolution we find 10-50 km changes in slab position and slab morphology and a slight change in overall slab tilt. Our study shows that remotely forced mantle flow leads to secondary effects on slab evolution as compared to slab buoyancy and plate motion. Still these secondary effects occur on scales, 10-50 km, typical for the large-scale deformation of the overlying crust and thus may still be of large importance for understanding geological evolution.

  17. Analysis of the equivalent indenter concept used to extract Young’s modulus from a nano-indentation test: some new insights into the Oliver–Pharr method

    DEFF Research Database (Denmark)

    Andriollo, Tito; Thorborg, Jesper; Hattel, Jesper Henri

    2017-01-01

    's elastic solution which is formally valid only for indentation into a flat surface. This allows for formulating the problem of extracting Young's modulus from the unloading curve as an optimization problem. However, it is proved that the latter does not have a unique solution, due to the particular...

  18. Segmented Coastal Uplift Along an Erosional Subduction Margin, Northern Hikurangi Fore Arc, North Island, New Zealand

    Science.gov (United States)

    Marshall, J. S.; Litchfield, N. J.; Berryman, K. R.; Clark, K.; Cochran, U. A.

    2013-12-01

    The Hikurangi subduction margin along North Island, New Zealand accommodates oblique convergence of the Pacific plate westward beneath the Australian plate at 45 mm/yr. Along the southern margin, frontal accretion and pronounced forearc uplift occur inboard of the subducting Hikurangi plateau. In the north, subduction erosion and segmented uplift occur inboard of subducting seamounts along the plateau flank. Prior workers have established a robust foundation for coastal terrace studies along the northern Hikurangi margin (e.g., Berryman et al., 1989; Ota et al., 1992; Berryman, 1993; Wilson et al., 2006, 2007; Clark et al., 2010; Litchfield et al, 2007, 2010). New field observations presented here provide additional constraints on terrace uplift along this erosional subduction margin. Along Raukumara Peninsula (north of Poverty Bay), multiple Holocene to late Pleistocene marine and fluvial terraces occur at varying elevations, recording differential uplift across six coastal segments from Gisborne to East Cape (Ota et al., 1992; Wilson et al., 2007). In this study, two to three late Pleistocene terraces were observed on rocky headlands within the first segment (Gisborne to Whangara) at elevations of 80-185 m above msl. Preliminary correlation with OIS 5a-e sea level high stands (80-125 ka) indicates net uplift at 1.2-1.5 m/ky. Uplifted Holocene wavecut platforms occur in steps along the seaward edge of these terraces, consistent with coseismic uplift. At Makorori Point, an uplifted bench occurs along the modern seacliff at 2.3 m above the cliff base. A fossil gastropod shell from paleo-beach gravels on the platform inner edge yielded a calibrated radiocarbon age of 1680 ×110 ybp. At Turihaua Point, a ≥1 m thick deposit of Holocene beach sands overlies an uplifted wavecut platform at ≥1.5 m above mean sea level. Carbonate-cemented beachrock at the base of the sand deposit yields a calibrated radiocarbon age of 2990 ×70 ybp. At Mahia Peninsula (between Poverty

  19. Popular perceptions of poverty in Dutch society

    NARCIS (Netherlands)

    Halman, L.C.J.M.; van Oorschot, W.J.H.

    1999-01-01

    Studies on poverty are mainly engaged with the definition and measurement of poverty, while the issue of what people consider reasons for living in need is often neglected. In this article we explore four types of poverty explanations based on a) the distinction between poverty as a matter of fate

  20. 7 CFR 25.104 - Poverty rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Poverty rate. 25.104 Section 25.104 Agriculture Office... § 25.104 Poverty rate. (a) General. Eligibility of an area on the basis of poverty shall be established in accordance with the following poverty rate criteria specific to Round I, Round II, Round IIS and...

  1. 24 CFR 598.115 - Poverty rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Poverty rate. 598.115 Section 598... Requirements § 598.115 Poverty rate. (a) General. In order to be eligible for designation, an area's poverty... poverty rate must be not less than 20 percent; and (2) For at least 90 percent of the census tracts within...

  2. 24 CFR 597.103 - Poverty rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Poverty rate. 597.103 Section 597... Area Requirements § 597.103 Poverty rate. (a) General. The poverty rate shall be established in accordance with the following criteria: (1) In each census tract within a nominated urban area, the poverty...

  3. Estimating Consumption- Based Poverty in the Ethiopia ...

    African Journals Online (AJOL)

    Inequalities in health are linked with poverty, but quantifying the health/poverty nexusis hampered by data constraints. In particular, the most common measure of poverty compares consumption with poverty lines, but consumption surveys often do not collect detailed health data. Conversely, the large repository of ...

  4. Belarus - Poverty Assessment: Can Poverty Reduction and Access to Services Be Sustained?

    OpenAIRE

    World Bank

    2004-01-01

    Building on the strong poverty analysis conducted by the government for almost a decade, this Poverty Assessment offers a number of improvements to the methodology for measuring poverty and living conditions in Belarus and contributes an in-depth analysis of the multiple dimensions of poverty-particularly the non-income dimensions (education and health). The poverty assessment also indicat...

  5. Growth, poverty and chronic poverty in rural Ethiopia: Evidence from 15 Communities 1994-2004

    NARCIS (Netherlands)

    Dercon, S.; Hoddinott, J.; Woldehanna, T.

    2008-01-01

    This paper examines growth, poverty and chronic poverty in 15 Ethiopian villages between 1994 and 2004. Growth and poverty reduction in these communities was substantial; headcount poverty fell from 48 to 35 percent. However, there is also movement in and out of poverty over this period and a

  6. Introduction: Reconsidering Culture and Poverty

    OpenAIRE

    Lamont, Michele; Small, Mario Luis; Harding, David J.

    2010-01-01

    To bridge the gap between poverty scholars and culture scholars, the editors have assembled papers around the topic "Reconsidering Culture and Poverty." Chapters concern cultural orientations concerning upward mobility, finding a job, and sexual behavior, fatherhood, civic participation, and other topics. Contributors include Nathan Fosse, Joshua Guetzkow, Biju Rao, Paromita Sanyal, Sandra Smith, Stephen Vaisey, Maureen Waller, and William Julius Wilson. We hope that this issue will demonstra...

  7. Joining together to combat poverty.

    Science.gov (United States)

    Heath, I; Haines, A; Malenica, Z; Oulton, J A; Leopando, Z; Kaseje, D; Addington, W W; Giscard D'Estaing, O; Tumwine, J K; Koivusalo, M; Biscoe, G; Nickson, P; Marusić, M; Vuk Pavlović, S

    2000-03-01

    The International Poverty and Health Network (IPHN) was created in December 1997 following a series of conferences organized by the World Health Organization, with the aim of integrating health into plans to eradicate poverty. Around 1.3 billion people live on less than US$1 per day. Of the 4.4 billion people in developing countries nearly 60% lack access to sanitation, 30% do not have clean water, 20% have no health care, and 20% do not have enough dietary energy and protein. Even among rich nations there are gross socioeconomic inequalities. Many children are robbed of their physical and mental potential through poverty. Expressed in constant 1963 US dollars, an average Croatian family needed the annual income of US$894 to meet the poverty line in 1960 and US$9,027 in 1995. Accordingly, 9-25% of Croatian households were below the poverty line between 1960 and 1995. The increase in the poverty rate after 1991 was compounded by the war that destroyed almost a third of industrial capacity and infrastructure. Dissipation of the communist economy and inadequate privatization have contributed to the increase in unemployment rate, corruption, and other social ills. IPHN invited Croatian Medical Journal to publish this editorial to help push the issue of poverty up political and medical agendas on a global level. We argue that a factor contributing to the failure of most large-scale programs against poverty to date is the excessive emphasis on material and infrastructure assistance at the expense of spiritual, moral, and intellectual development.

  8. The poverty of liberal economics

    OpenAIRE

    Brady, David

    2003-01-01

    Liberal economic precepts have long been a foundation for the social science of poverty and continue to profoundly influence public policy. Liberal economics contends that poverty is dependent on the harmonious progress of economic growth, free market capitalism, worker productivity, and the supply and demand of labor. This paper traces its origins from classical economics and its influence throughout contemporary social science, public policy and conventional wisdom. Next, I evaluate the lib...

  9. Evaluation of the degradation characteristics of CF-8A cast stainless steel using EDS and nano-indentation

    International Nuclear Information System (INIS)

    Baek, Seung; Koo, Jae Mean; Seok, Chang Sung

    2004-01-01

    Cast austenitic stainless steel piping pump, valve casings, and elbows are susceptible to reductions in toughness and ductility because of long term exposure at the operating temperatures in LWR(Light Water Reactor). In this paper, we have measured the material properties of long term aged CF-8A cast stainless steel, accelerated aging at 400 .deg. C. These studies have been carried out using indentation tests(automated ball indentation and nano-indentation) and EDS(Energy Dispersive Spectroscopy). The fracture toughness of Cf-8A cast stainless steel was also determined by using standard fracture toughness and automated ball indentation

  10. Influence of heat treatment and indenter tip material on depth sensing hardness tests at high temperatures of fusion relevant materials

    International Nuclear Information System (INIS)

    Bredl, Julian; Dany, Manuel; Albinski, Bartlomiej; Schneider, Hans-Christian; Kraft, Oliver

    2015-01-01

    Highlights: • Operation of a custom-made indentation device designed for test temperatures up to 650 °C and a remote handled operation in a Hot Cell. • Instrumented indentation and conventional hardness testing of unirradiated MANET II and EUROFER. • Comparison of diamond and sapphire as indenter tip materials. - Abstract: The instrumented indentation is a suitable method for testing of even small neutron-irradiated specimens. From the continuously recorded indentation depth and the indentation force, it is possible to deduce mechanical parameters of the tested material. In this paper, a brief description of the high temperature device is given and representative results are presented. In the study, unirradiated steels are investigated by instrumented indentation at temperatures up to 500 °C. It is shown that the hardness is highly depending on the testing-temperature and can be correlated to the results of conventional tensile testing experiments. A not negligible influence of the indenter tip material is observed. The results show the functionality of the high-temperature indentation device.

  11. Freedom and poverty in the fishery commons

    OpenAIRE

    Svein Jentoft; Paul Onyango; Mohammad Mahmudul Islam

    2010-01-01

    Abstract In fisheries, alleviating poverty sometimes requires strategies that are inherently in conflict. When aiming to develop a fishery as a means to reduce poverty, its common pool resource basis might be undermined, resulting in greater poverty. But poverty in fisheries is also linked to, or a part of deeper social issues and processes, for instance, the marginalization and exclusion of certain communities. Poverty also has many factors— income, health, literacy, gender, power, sec...

  12. The effect of religion on poverty

    OpenAIRE

    Jaco Beyers

    2014-01-01

    Poverty is a human condition. Social, economic, psychological and political factors affect society and can alleviate as well as stimulate poverty. Religion provides a unique perspective on the phenomenon of poverty. This article suggests three functions of religion regarding poverty. Firstly, religion can redirect human thought to spiritual concerns, focusing on spiritual poverty instead of material concerns. Secondly, it can provide the moral fibres needed in society. Religion can influence ...

  13. Indentation modulus and hardness of viscoelastic thin films by atomic force microscopy: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Passeri, D., E-mail: daniele.passeri@uniroma1.it [Dipartimento di Energetica, Universita di Roma ' La Sapienza' , Via A. Scarpa 16, 00161 Roma (Italy); Bettucci, A.; Biagioni, A.; Rossi, M.; Alippi, A. [Dipartimento di Energetica, Universita di Roma ' La Sapienza' , Via A. Scarpa 16, 00161 Roma (Italy); Tamburri, E. [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Roma (Italy); Lucci, M.; Davoli, I. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Roma (Italy); Berezina, S. [Department of Physics, University of Zilina, 01026, Univerzitna 1 Zilina (Slovakia)

    2009-11-15

    We propose a nanoindentation technique based on atomic force microscopy (AFM) that allows one to deduce both indentation modulus and hardness of viscoelastic materials from the force versus penetration depth dependence, obtained by recording the AFM cantilever deflection as a function of the sample vertical displacement when the tip is pressed against (loading phase) and then removed from (unloading phase) the surface of the sample. Reliable quantitative measurements of both indentation modulus and hardness of the investigated sample are obtained by calibrating the technique through a set of different polymeric samples, used as reference materials, whose mechanical properties have been previously determined by standard indentation tests. By analyzing the dependence of the cantilever deflection versus time, the proposed technique allows one to evaluate and correct the effect of viscoelastic properties of the investigated materials, by adapting a post-experiment data processing procedure well-established for standard depth sensing indentation tests. The technique is described in the case of the measurement of indentation modulus and hardness of a thin film of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate), deposited by chronoamperometry on an indium tin oxide (ITO) substrate.

  14. Site-controlled fabrication of silicon nanotips by indentation-induced selective etching

    Science.gov (United States)

    Jin, Chenning; Yu, Bingjun; Liu, Xiaoxiao; Xiao, Chen; Wang, Hongbo; Jiang, Shulan; Wu, Jiang; Liu, Huiyun; Qian, Linmao

    2017-12-01

    In the present study, the indentation-induced selective etching approach is proposed to fabricate site-controlled pyramidal nanotips on Si(100) surface. Without any masks, the site-controlled nanofabrication can be realized by nanoindentation and post etching in potassium hydroxide (KOH) solution. The effect of indentation force and etching time on the formation of pyramidal nanotips was investigated. It is found that the height and radius of the pyramidal nanotips increase with the indentation force or etching time, while long-time etching can lead to the collapse of the tips. The formation of pyramidal tips is ascribed to the anisotropic etching of silicon and etching stop of (111) crystal planes in KOH aqueous solution. The capability of this fabrication method was further demonstrated by producing various tip arrays on silicon surface by selective etching of the site-controlled indent patterns, and the maximum height difference of these tips is less than 10 nm. The indentation-induced selective etching provides a new strategy to fabricate well site-controlled tip arrays for multi-probe SPM system, Si nanostructure-based sensors and high-quality information storage.

  15. Evaluation of deformation and fracture characteristics of nuclear reactor materials using ball indentation test technique

    International Nuclear Information System (INIS)

    Byun, T. S.; Hong, J. H.; Lee, B. S.; Park, D. G.; Kim, J. H.; Oh, Y. J.; Yoon, J. H.; Chi, S. H.; Kuk, I. H.; Kwon, D. I.; Lee, J. H.

    1998-05-01

    The present report describes the automated ball indentation test techniques and the results of their applications. The ball indentation test technique is an innovative method for evaluating the key mechanical properties from the indentation load-depth data. In the 1st chapter, the existing technique for evaluating basic deformation (tensile) properties is described in detail, and also the application result of the technique is presented. The through-thickness variations of mechanical properties in SA 508 C1.3 reactor pressure vessel steels were measured using an automated ball indentation (ABI) technique. In the 2nd chapter, a method under development, which is similar to that in the 1st chapter, is new method is based on the theoretical solutions rather than experimental relationships. The result of the application showed that the stress-strain curves of various metals were successfully determined with the method. In the 3rd chapter, a new theoretical model was proposed to estimate the fracture toughness of ferritic steels in the transition temperature region. The key concept of the model is that the indention energy to a critical load is related to the fracture energy of the material. The theory was applied to the reactor pressure vessel (RPV) base and weld metals. (author). 24 refs., 3 tabs., 6 figs

  16. Atomic mechanism of shear localization during indentation of a nanostructured metal

    International Nuclear Information System (INIS)

    Sansoz, F.; Dupont, V.

    2007-01-01

    Shear localization is an important mode of deformation in nanocrystalline metals. However, it is very difficult to verify the existence of local shear planes in nanocrystalline metals experimentally. Sharp indentation techniques may provide novel opportunities to investigate the effect of shear localization at different length scales, but the relationship between indentation response and atomic-level shear band formation has not been fully addressed. This paper describes an effort to provide direct insight on the mechanism of shear localization during indentation of nanocrystalline metals from atomistic simulations. Molecular statics is performed with the quasi-continuum method to simulate the indentation of single crystal and nanocrystalline Al with a sharp cylindrical probe. In the nanocrystalline regime, two grain sizes are investigated, 5 nm and 10 nm. We find that the indentation of nanocrystalline metals is characterized by serrated plastic flow. This effect seems to be independent of the grain size. Serration in nanocrystalline metals is found to be associated with the formation of shear bands by sliding of aligned interfaces and intragranular slip, which results in deformation twinning

  17. Method to determine the optimal constitutive model from spherical indentation tests

    Science.gov (United States)

    Zhang, Tairui; Wang, Shang; Wang, Weiqiang

    2018-03-01

    The limitation of current indentation theories was investigated and a method to determine the optimal constitutive model through spherical indentation tests was proposed. Two constitutive models, the Power-law and the Linear-law, were used in Finite Element (FE) calculations, and then a set of indentation governing equations was established for each model. The load-depth data from the normal indentation depth was used to fit the best parameters in each constitutive model while the data from the further loading part was compared with those from FE calculations, and the model that better predicted the further deformation was considered the optimal one. Moreover, a Yang's modulus calculation model which took the previous plastic deformation and the phenomenon of pile-up (or sink-in) into consideration was also proposed to revise the original Sneddon-Pharr-Oliver model. The indentation results on six materials, 304, 321, SA508, SA533, 15CrMoR, and Fv520B, were compared with tensile ones, which validated the reliability of the revised E calculation model and the optimal constitutive model determination method in this study.

  18. Indentation Size Effects in Single Crystal Copper as Revealed by Synchrotron X-ray Microdiffraction

    Energy Technology Data Exchange (ETDEWEB)

    Feng, G.; Budiman, A. S.; Nix, W. D.; Tamura, N.; Patel, J. R.

    2007-11-19

    The indentation size effect (ISE) has been observed in numerous nanoindentation studies on crystalline materials; it is found that the hardness increases dramatically with decreasing indentation size - a 'smaller is stronger' phenomenon. Some have attributed the ISE to the existence of strain gradients and the geometrically necessary dislocations (GNDs). Since the GND density is directly related to the local lattice curvature, the Scanning X-ray Microdiffraction ({mu}SXRD) technique, which can quantitatively measure relative lattice rotations through the streaking of Laue diffractions, can used to study the strain gradients. The synchrotron {mu}SXRD technique we use - which was developed at the Advanced Light Source (ALS), Berkeley Lab - allows for probing the local plastic behavior of crystals with sub-micrometer resolution. Using this technique, we studied the local plasticity for indentations of different depths in a Cu single crystal. Broadening of Laue diffractions (streaking) was observed, showing local crystal lattice rotation due to the indentation-induced plastic deformation. A quantitative analysis of the streaking allows us to estimate the average GND density in the indentation plastic zones. The size dependence of the hardness, as found by nanoindentation, will be described, and its correlation to the observed lattice rotations will be discussed.

  19. A Comparison of Quasi-Static Indentation Testing to Low Velocity Impact Testing

    Science.gov (United States)

    Nettles, Alan T.; Douglas, Michael J.

    2001-01-01

    The need for a static test method for modeling low-velocity foreign object impact events to composites would prove to be very beneficial to researchers since much more data can be obtained from a static test than from an impact test. In order to examine if this is feasible, a series of static indentation and low velocity impact tests were carried out and compared. Square specimens of many sizes and thickness were utilized to cover the array of types of low velocity impact events. Laminates with a n/4 stacking sequence were employed since this is by the most common type of engineering laminate. Three distinct flexural rigidities under two different boundary conditions were tested in order to obtain damage due to large deflections, contact stresses and both to examine if the static indentation-impact comparisons are valid under the spectrum of damage modes that can be experienced. Comparisons between static indentation and low velocity impact tests were based on the maximum applied transverse load. The dependent parameters examined included dent depth, back surface crack length, delamination area and to a limited extent, load-deflection behavior. Results showed that no distinct differences could be seen between the static indentation tests and the low velocity impact tests, indicating that static indentation can be used to represent a low velocity impact event.

  20. Subduction zones seen by GOCE gravity gradients

    DEFF Research Database (Denmark)

    Švarc, Mario; Herceg, Matija; Cammarano, Fabio

    . Few pattern recognition methods were tested on all 6 gravity gradient tensor components represented as global scale maps with resolution of 100km (corresponds to the resolution of the GOCE satellite data). By adjusting pattern recognition methods’ features and optimizing various input patterns...... and used as starting point for analysis based on image processing. On obtained maps, locations of known subduction zones were represented with characteristic elongated patterns and cross-sections. Cross sections of well-known subduction zones were used as input patterns for pattern recognition method......, the best method was applied. That is a combination of methods based on SURF (Speeded Up Robust Features) and MSER (Maximally Stable Extremal Regions) algorithms provided in MATLAB’s Computer Vision System Toolbox. Based on 6 gravity gradient components, the global gradient anomaly maps were produced...

  1. On the dip angle of subducting plates

    Science.gov (United States)

    Hsui, Albert T.; Tang, Xiao-Ming; Toksoz, M. Nafi

    1990-01-01

    A new approximate analytic model is developed for the thermal structure of a subducting plate with a finite length. This model provides the capability of easily examining the thermal and mechanical structure of a subducting plate with different lengths and at different angles. Also, the torque balance of a descending plate can be examined, and effects such as the leading edge effect, the adiabatic compression effect, and the phase change effect can be incorporated. A comparison with observed data indicates that short slabs are likely under torque equilibrium at present, while long slabs are probably dominated by their gravitational torques such that their dip angles are transient, moving toward a steeper dip angle similar to that of the Mariana slab.

  2. Imaging Shear Strength Along Subduction Faults

    Science.gov (United States)

    Bletery, Quentin; Thomas, Amanda M.; Rempel, Alan W.; Hardebeck, Jeanne L.

    2017-11-01

    Subduction faults accumulate stress during long periods of time and release this stress suddenly, during earthquakes, when it reaches a threshold. This threshold, the shear strength, controls the occurrence and magnitude of earthquakes. We consider a 3-D model to derive an analytical expression for how the shear strength depends on the fault geometry, the convergence obliquity, frictional properties, and the stress field orientation. We then use estimates of these different parameters in Japan to infer the distribution of shear strength along a subduction fault. We show that the 2011 Mw9.0 Tohoku earthquake ruptured a fault portion characterized by unusually small variations in static shear strength. This observation is consistent with the hypothesis that large earthquakes preferentially rupture regions with relatively homogeneous shear strength. With increasing constraints on the different parameters at play, our approach could, in the future, help identify favorable locations for large earthquakes.

  3. Imaging shear strength along subduction faults

    Science.gov (United States)

    Bletery, Quentin; Thomas, Amanda M.; Rempel, Alan W.; Hardebeck, Jeanne L.

    2017-01-01

    Subduction faults accumulate stress during long periods of time and release this stress suddenly, during earthquakes, when it reaches a threshold. This threshold, the shear strength, controls the occurrence and magnitude of earthquakes. We consider a 3-D model to derive an analytical expression for how the shear strength depends on the fault geometry, the convergence obliquity, frictional properties, and the stress field orientation. We then use estimates of these different parameters in Japan to infer the distribution of shear strength along a subduction fault. We show that the 2011 Mw9.0 Tohoku earthquake ruptured a fault portion characterized by unusually small variations in static shear strength. This observation is consistent with the hypothesis that large earthquakes preferentially rupture regions with relatively homogeneous shear strength. With increasing constraints on the different parameters at play, our approach could, in the future, help identify favorable locations for large earthquakes.

  4. Heterogeneity in Subducting Slab Influences Fluid Properties, Plate Coupling and Volcanism: Hikurangi Subduction Zone, New Zealand

    Science.gov (United States)

    Eberhart-Phillips, D. M.; Reyners, M.; Bannister, S. C.

    2017-12-01

    Seismicity distribution and 3-D models of P- and S-attenuation (1/Q) in the Hikurangi subduction zone, in the North Island of New Zealand, show large variation along-arc in the fluid properties of the subducting slab. Volcanism is also non-uniform, with extremely productive rhyolitic volcanism localized to the central Taupo Volcanic zone, and subduction without volcanism in the southern North Island. Plate coupling varies with heterogeneous slip deficit in the northern section, low slip deficit in the central section, and high slip deficit (strong coupling) in the south. Heterogeneous initial hydration and varied dehydration history both are inferred to play roles. The Hikurangi Plateau (large igneous province) has been subducted beneath New Zealand twice - firstly at ca. 105-100 Ma during north-south convergence with Gondwana, and currently during east-west convergence between the Pacific and Australian plates along the Hikurangi subduction zone. It has an uneven downdip edge which has produced spatially and temporally localized stalls in subduction rate. The mantle wedge under the rhyolitic section has a very low Q feature centred at 50-125 km depth, which directly overlies a 150-km long zone of dense seismicity. This seismicity occurs below a sharp transition in the downdip extent of the Hikurangi Plateau, where difficulty subducting the buoyant plateau would have created a zone of increased faulting and hydration that spent a longer time in the outer-rise yielding zone, compared with areas to the north and south. At shallow depths this section has unusually high fracture permeability from the two episodes of bending, but it did not experience dehydration during Gondwana subduction. This central section at plate interface depths less than 50-km has low Q in the slab crust, showing that it is extremely fluid rich, and it exhibits weak plate coupling with both deep and shallow slow-slip events. In contrast in the southern section, where there is a large deficit in

  5. Constraining subducted slab properties with deep earthquakes

    Science.gov (United States)

    Zhan, Z.; Yang, T.; Gurnis, M.; Shen, Z.; Wu, F.

    2017-12-01

    The discovery of deep earthquakes and Wadati-Benioff zone was a critical piece in the early history of plate tectonics. Today, deep earthquakes continue to serve as important markers/probes of subducted slab geometry, structure, and stress state. Here we discuss three examples in which we have recently used deep earthquakes to provide new insights to subducted slab properties. In the first application, we investigate the slab morphology and stress regimes under different trench motion histories with geodynamic models. We find that the isolation of the 2015 Mw 7.9 Bonin Islands deep earthquake from the background Wadati-Benioff zone may be explained as a result of Pacific slab buckling in response to the slow trench retreat. Additionally, subducted slab is inherently heterogeneous due to non-linear viscosity, contributing to the occurrences of isolated deep earthquakes. In the second application, we quantify the coda waveform differences from nearby deep earthquakes to image fine-scale slab structures. We find that large metastable olivine wedge suggested by several previous studies can not fit our observations. Therefore, the effects of metastable olivine on slab dynamics should be re-assessed. In the third application, we take advantage of P and S differential travel times from deep earthquake clusters to isolate signatures of Vp/Vs ratios within slabs from ambient mantle. We observe substantial deviations of slab Vp/Vs from that in 1D reference Earth models, and even possible lateral variations. This sheds light on potential difference in slab temperature or water content. All three applications underscore that deep earthquakes are still incredibly useful in informing us more about subducted slabs.

  6. Diamond Growth in the Subduction Factory

    Science.gov (United States)

    Bureau, H.; Frost, D. J.; Bolfan-Casanova, N.; Leroy, C.; Estève, I.

    2014-12-01

    Natural diamonds are fabulous probes of the deep Earth Interior. They are the evidence of the deep storage of volatile elements, carbon at first, but also hydrogen and chlorine trapped as hydrous fluids in inclusions. The study of diamond growth processes in the lithosphere and mantle helps for our understanding of volatile elements cycling between deep reservoirs. We know now that inclusion-bearing diamonds similar to diamonds found in nature (i.e. polycrystalline, fibrous and coated diamonds) can grow in hydrous fluids or melts (Bureau et al., GCA 77, 202-214, 2012). Therefore, we propose that the best environment to promote such diamonds is the subduction factory, where highly hydrous fluids or melts are present. When oceanic plates are subducted in the lithosphere, they carry an oceanic crust soaked with seawater. While the slabs are traveling en route to the mantle, dehydration processes generate saline fluids highly concentrated in NaCl. In the present study we have experimentally shown that diamonds can grow from the saline fluids (up to 30 g/l NaCl in water) generated in subducted slabs. We have performed multi-anvil press experiments at 6-7 GPa and from 1300 to 1400°C during 6:00 hours to 30:00 hours. We observed large areas of new diamond grown in epitaxy on pure diamond seeds in salty hydrous carbonated melts, forming coated gems. The new rims are containing multi-component primary inclusions. Detailed characterizations of the diamonds and their inclusions have been performed and will be presented. These experimental results suggest that multi-component salty fluids of supercritical nature migrate with the slabs, down to the deep mantle. Such fluids may insure the first stage of the deep Earth's volatiles cycling (C, H, halogen elements) en route to the transition zone and the lower mantle. We suggest that the subduction factory may also be a diamond factory.

  7. A theoretical study on poverty | Roohbakhsh | Journal of ...

    African Journals Online (AJOL)

    ... the concepts of poverty, various approaches to poverty and its related issues such as education, health, housing and etc. are considered. Finally, measuring poverty from different researchers' views and their critical perspectives are discussed. Keywords: Poverty, Discourses on poverty, Absolute Poverty, Poverty Line ...

  8. [An end to poverty

    Science.gov (United States)

    Engelhard, P

    1994-10-01

    The African continent is distinguished by a much higher fertility rate than other regions. Fertility in Africa has remained almost constant at slightly over six children per woman on average, while important declines have occurred elsewhere over the past 25 years. High fertility in Africa is often attributed to poor diffusion of family planning, early marriage, and low female educational attainment, but other cultural and economic factors are involved. The significant decline of infant mortality over the past several decades has produced growth rates never before observed. Africa's very young populations may be at the origin of uncontrollable political disorder, as young persons with bleak prospects fall easy prey to ethnic, religious, and political extremism. Demographic growth has become an additional barrier to development. High fertility is tolerated or encouraged as constituting a cultural trait, but the resulting population growth is not a cultural trait. Demographic pressure has increased environmental problems in many regions. It is estimated that over ten million rural residents of the Sahel have been affected by soil degradation. The per capita availability of arable land fell from one-half to one-third hectare between 1965 and 1987. Shortages of firewood and water have become more common. The relationship between demographic growth, environmental crisis, and poverty in the countryside depends on other factors such as production techniques, modes of access to land and water, and the degree of security of land tenure. Population pressure was not the initial factor that disturbed the balance of the traditional societies, but it exacerbated the effects of other forces such as the introduction of cash crops and monetarization of the economy. Rural exodus and accelerated urban migration have been prompted in large part by the higher incomes and greater availability of services of all types in the cities. Achieving control of fertility in Africa will require

  9. Childhood nutrition and poverty.

    Science.gov (United States)

    Nelson, M

    2000-05-01

    One in three children in Britain lives in poverty (households whose income was less than 50% average earnings). Low income is associated with poor nutrition at all stages of life, from lower rates of breast-feeding to higher intakes of saturated fatty acids and lower intakes of antioxidant nutrients. Moreover, there is increasing evidence that poor nutrition in childhood is associated with both short-term and long-term adverse consequences such as poorer immune status, higher caries rates and poorer cognitive function and learning ability. These problems arise primarily because parents do not have enough money to spend on food, not because money is being spent unwisely. Policy options to improve the dietary health of poor children include: giving more money to the parents by increasing Income Support (social security) payments, providing food stamps or vouchers, and using food budget standards to inform the levels of income needed to purchase an adequate diet; feeding children directly at school (not only at lunchtime but also at breakfast or homework clubs), by providing free fruit at school, and by increasing entitlement to free food amongst children living in households with low incomes; improving access to a healthy and affordable diet by first identifying 'food deserts' and then considering with retailers and local planners how best to provide food in an economical and sustainable way. The value of using food budget standards is illustrated with data relating expenditure on food to growth in children from 'at-risk' families (on low income, overcrowded, headed by a lone parent or with four or more children under 16 years of age) living in a poor area in London. Lower levels of expenditure are strongly associated with poorer growth and health, independent of factors such as birth weight, mother's height, or risk score. The present paper provides evidence that supports the need to review Government legislation in light of nutrition-related inequalities in the

  10. Mechanical evaluation of five flowable resin composites by the dynamic micro-indentation method.

    Science.gov (United States)

    Hirayama, Satoshi; Iwai, Hirotoshi; Tanimoto, Yasuhiro

    2014-01-01

    Measurement of the strength of brittle materials, such as resin composites, is extremely difficult. Micro-indentation hardness testing is a convenient way of investigating the mechanical properties of a small volume of material. In this study, the mechanical properties of five commercially available flowable resin composites were investigated by the dynamic micro-indentation method. Additionally, the effects of inorganic-filler content on the dynamic hardness and elastic modulus of flowable composites obtained by this method were investigated. The weight percentages of the inorganic fillers in the resin composites were determined by the ashing technique. The results indicate that the mechanical properties of flowable composites are affected by not only the filler content but also the properties of the resin matrix. In conclusion, the dynamic micro-indentation method is a useful technique for determining the mechanical behavior of dental resin composites as brittle material.

  11. Using the ultrasound and instrumented indentation techniques to measure the elastic modulus of engineering materials

    International Nuclear Information System (INIS)

    Meza, J. M.; Franco, E. E.; Farias, M. C. M.; Buiochi, F.; Souza, R. M.; Cruz, J.

    2008-01-01

    Currently, the acoustic and nano indentation techniques are two of the most used techniques for materials elastic modulus measurement. In this article fundamental principles and limitations of both techniques are shown and discussed. Last advances in nano indentation technique are also reviewed. an experimental study in ceramic, metallic, composite and single crystals was also done. Results shown that ultrasonic technique is capable to provide results in agreement with those reported in literature. However, ultrasonic technique does not allow measuring the elastic modulus of some small samples and single crystals. On the other hand, the nano indentation technique estimates the elastic modulus values in reasonable agreement with those measured by acoustic methods, particularly in amorphous materials, while in some policristaline materials some deviation from expected values was obtained. (Author) 29 refs

  12. Evaluation of hot hardness, creep, fatigue and fracture properties of zirconia ceramics by an indentation technique

    International Nuclear Information System (INIS)

    Kutty, T.R.G.; Ganguly, C.; Upadhyaya, D.D.

    1996-01-01

    Zirconia ceramics have wide range engineering applications at room and elevated temperatures. For understanding the mechanical behaviour, the indentation technique was adapted for quick evaluation of hot hardness, creep, fatigue and fracture properties. A Vicker's diamond indentor with 10 N load was employed for hot hardness and creep measurement up to 1300 deg. The fatigue data were evaluated at room temperature by repeated indentation with a constant load (10-2500N) at the same location for a dwell time of 5s until it resulted in the formation of a lateral chip on the sample surface. Thus, the number of cycles for chip formation at a specific indentation load was obtained. The fracture toughness was evaluated at room temperature with a load of 300N using a Vicker's diamond indentor. The results of hot hardness, creep, fatigue, and fracture data ol 3Y-TZP and Mg-PSZ are discussed along with their microstructural features. (authors)

  13. Derivation of tensile flow characteristics for austenitic materials from instrumented indentation technique

    International Nuclear Information System (INIS)

    Lee, K-W; Kim, K-H; Kim, J-Y; Kwon, D

    2008-01-01

    In this study, a method for deriving the tensile flow characteristics of austenitic materials from an instrumented indentation technique is presented along with its experimental verification. We proposed a modified algorithm for austenitic materials that takes their hardening behaviour into account. First, the true strain based on sine function instead of tangent function was adapted. It was proved that the sine function shows constant degrees of hardening which is a main characteristic of the hardening of austenitic materials. Second, a simple and linear constitutive equation was newly suggested to optimize indentation flow curves. The modified approach was experimentally verified by comparing tensile properties of five austenitic materials from uniaxial tensile test and instrumented indentation tests

  14. Analysis of the Indented Cylinder by the use of Computer Vision

    DEFF Research Database (Denmark)

    Buus, Ole Thomsen

    The research summarised in this PhD thesis took advantage of methods from computer vision to experimentally analyse the sorting/separation ability of a specific type of seed sorting device – known as an “indented cylinder”. The indented cylinder basically separates incoming seeds into two sub......-groups: (1) “long” seeds and (2) “short” seeds (known as length-separation). The motion of seeds being physically manipulated inside an active indented cylinder was analysed using various computer vision methods. The data from such analyses were used to create an overview of the machine’s ability to separate...... all the complexities related to that as well. The project arrived at a number of results of high scientific and practical value to the area of applied computer vision and seed processing and agricultural technology in general. The results and methodologies were summarised in one conference paper...

  15. Overthrusting versus subduction beneath southern Hispaniola

    Science.gov (United States)

    Llanes Estrada, M.; Carbó-Gorosabel, A.; ten Brink, U. S.; Granja Bruña, J.; Flores, C. H.; Villasenor, A.; Davila, J. M.; Pazos, A.

    2011-12-01

    Recent observations of the deformational features on the Muertos compressive margin together with sandbox kinematic and gravity modeling question the hypothesized subduction of the Caribbean plate's interior beneath the eastern Greater Antilles island arc. With the aim of testing such subduction, we carried out a wide-angle seismic transect across the widest part of the Muertos compressive margin (longitude 69°W) in the spring of 2009. Shots were fired along the 200 km transect every 90 seconds from the R/V Hesperides' 3850 cubic inches water-gun array, which, towed at 5 knots, resulted in a shot spacing of ~ 230 m. The seismic signal was recorded by five ocean-bottom seismometers deployed at distance intervals from 30 to 50 km. Adjacent reprocessed reflection seismic lines and previous works provided an initial model of the sediment column and the geometry of upper crustal reflectors. A 2-D forward ray-tracing model of the wide-angle transect outlines the broad-scale crustal structure across the Muertos margin. The Caribbean oceanic slab is imaged underneath the Muertos margin to about 50 km north of the deformation front and up to 19 km depth. A change in crustal p-wave velocity at ~60 km from the deformation front is interpreted to be the boundary between the arc crust and the compressive deformed belt. The Caribbean oceanic crust is not seen extending farther north. Results from gravity modeling using ship data acquired on the seismic profile corroborate a model of an overthrusted Caribbean oceanic slab extending a few tens of km northward from the compressive deformation front and rejects a subduction process, independently of the geometry of the slab used or its angle. In addition to the seismic experiment and the gravity modeling, vertical cross-sections of p-wave global tomography do not show northward inclination of a fast velocity layer into the upper mantle suggesting that the Caribbean plate's interior does not subduct under the Muertos margin. Overall

  16. Elastic modulus of claystone evaluated by nano-/micro-indentation tests and meso-compression tests

    Directory of Open Access Journals (Sweden)

    Christophe Auvray

    2017-02-01

    Full Text Available Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates (clay minerals, quartz, feldspars, micas (≈86%, sulphides (pyrite (≈3%, carbonates (calcite, dolomite (≈10% and organic kerogen (≈1%. Three sets of measurements of the modulus of deformability were compared as determined in (i nano-indentation tests with a constant indentation depth of 2 μm, (ii micro-indentation tests with a constant indentation depth of 20 μm, and (iii meso-compression tests with a constant displacement of 200 μm. These three experimental methods have already been validated in earlier studies. The main objective of this study is to demonstrate the influence of the scaling effect on the modulus of deformability of the material. Different frequency distributions of the modulus of deformability were obtained at the different sample scales: (i in nano-indentation tests, the distribution was spread between 15 GPa and 90 GPa and contained one peak at 34 GPa and another at 51 GPa; (ii in the micro-indentation tests, the distribution was spread between 25 GPa and 60 GPa and displayed peaks at 26 GPa and 37 GPa; and (iii in the meso-compression tests, a narrow frequency distribution was obtained, ranging from 25 GPa to 50 GPa and with a maximum at around 35 GPa.

  17. Postcollisional cooling history of the Eastern and Southern Alps and its linkage to Adria indentation

    Science.gov (United States)

    Heberer, Bianca; Reverman, Rebecca Lee; Fellin, Maria Giuditta; Neubauer, Franz; Dunkl, István; Zattin, Massimiliano; Seward, Diane; Genser, Johann; Brack, Peter

    2017-07-01

    Indentation of rigid blocks into rheologically weak orogens is generally associated with spatiotemporally variable vertical and lateral block extrusion. The European Eastern and Southern Alps are a prime example of microplate indentation, where most of the deformation was accommodated north of the crustal indenter within the Tauern Window. However, outside of this window only the broad late-stage exhumation pattern of the indented units as well as of the indenter itself is known. In this study we refine the exhumational pattern with new (U-Th-Sm)/He and fission-track thermochronology data on apatite from the Karawanken Mountains adjacent to the eastern Periadriatic fault and from the central-eastern Southern Alps. Apatite (U-Th-Sm)/He ages from the Karawanken Mountains range between 12 and 5 Ma and indicate an episode of fault-related exhumation leading to the formation of a positive flower structure and an associated peripheral foreland basin. In the Southern Alps, apatite (U-Th-Sm)/He and fission-track data combined with previous data also indicate a pulse of mainly Late Miocene exhumation, which was maximized along thrust systems, with highly differential amounts of displacement along individual structures. Our data contribute to mounting evidence for widespread Late Miocene tectonic activity, which followed a phase of major exhumation during strain localization in the Tauern Window. We attribute this exhumational phase and more distributed deformation during Adriatic indentation to a major change in boundary conditions operating on the orogen, likely due to a shift from a decoupled to a coupled system, possibly enhanced by a shift in convergence direction.

  18. The Africanization of poverty: a retrospective on "Make Poverty History".

    Science.gov (United States)

    Harrison, Graham

    2010-01-01

    This article explores the ways in which the British campaign coalition Make Poverty History represented Africa throughout 2005. Focusing particularly on the G8 Gleneagles summit, Make Poverty History (MPH) asserted a series of justice claims which had no geographical reference. Nevertheless, as a result of internal tensions within the coalition, and especially as a result of the ways in which MPH interacted with other political agencies as the summit approached, MPH's messages became increasingly interpolated by references to Africa as a result of the emergence of government, media, and celebrity involvement. The result of this was that global poverty increasingly became an African issue. As 2005 became the "Year of Africa," the justice messages that constituted MPH were largely effaced by the more familiar imperial legacy which represents Africa as a place of indigence in need of outside assistance.

  19. Velocities of Subducted Sediments and Continents

    Science.gov (United States)

    Hacker, B. R.; van Keken, P. E.; Abers, G. A.; Seward, G.

    2009-12-01

    The growing capability to measure seismic velocities in subduction zones has led to unusual observations. For example, although most minerals have VP/ VS ratios around 1.77, ratios 1.8 have been observed. Here we explore the velocities of subducted sediments and continental crust from trench to sub-arc depths using two methods. (1) Mineralogy was calculated as a function of P & T for a range of subducted sediment compositions using Perple_X, and rock velocities were calculated using the methodology of Hacker & Abers [2004]. Calculated slab-top temperatures have 3 distinct depth intervals with different dP/dT gradients that are determined by how coupling between the slab and mantle wedge is modeled. These three depth intervals show concomitant changes in VP and VS: velocities initially increase with depth, then decrease beyond the modeled decoupling depth where induced flow in the wedge causes rapid heating, and increase again at depth. Subducted limestones, composed chiefly of aragonite, show monotonic increases in VP/ VS from 1.63 to 1.72. Cherts show large jumps in VP/ VS from 1.55-1.65 to 1.75 associated with the quartz-coesite transition. Terrigenous sediments dominated by quartz and mica show similar, but more-subdued, transitions from ~1.67 to 1.78. Pelagic sediments dominated by mica and clinopyroxene show near-monotonic increases in VP/ VS from 1.74 to 1.80. Subducted continental crust that is too dry to transform to high-pressure minerals has a VP/ VS ratio of 1.68-1.70. (2) Velocity anisotropy calculations were made for the same P-T dependent mineralogies using the Christoffel equation and crystal preferred orientations measured via electron-backscatter diffraction for typical constituent phases. The calculated velocity anisotropies range from 5-30%. For quartz-rich rocks, the calculated velocities show a distinct depth dependence because crystal slip systems and CPOs change with temperature. In such rocks, the fast VP direction varies from slab-normal at

  20. Effect of Properties and Turgor Pressure on the Indentation Response of Plant Cells

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Needleman, Alan

    2018-01-01

    The indentation of plant cells by a conical indenter is modeled. The cell wall is represented as a spherical shell consisting of a relatively stiff thin outer layer and a softer thicker inner layer. The state of the interior of the cell is idealized as a specified turgor pressure. Attention...... is restricted to axisymmetric deformations, and the wall material is characterized as a viscoelastic solid with different properties for the inner and outer layers. Finite deformation, quasi-static calculations are carried out. The effects of outer layer stiffness, outer layer thickness, turgor pressure...

  1. Strain gradient effects in periodic flat punch indenting at small scales

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau; Niordson, Christian Frithiof; Hutchinson, J. W.

    2014-01-01

    Experiments on soft polycrystalline aluminum have yielded evidence that, besides the required punch load, both the size and shape of imprinted features are affected by the scale of the set-up, e.g. substantial details are lost when the characteristic length is on the order of 10μm. The objective...... of this work is to clarify the role played by strain gradients on this issue, and to shed light on the underlying mechanisms. For this, indentation by a periodic array of flat punch indenters is considered, and a gradient enhanced material model that allows for a numerical investigation of the fundamentals...

  2. Polarity influence on the indentation punching of thin {111} GaAs foils at elevated temperatures

    International Nuclear Information System (INIS)

    Patriarche, G; Largeau, L; Riviere, J P; Bourhis, E Le

    2005-01-01

    Thin {111} GaAs substrates were deformed by a Vickers indenter at 350 deg. C-370 deg. C under loads ranging between 0.4 and 1.9 N. Optical microscopy and interferometry were used to observe the indented and opposite faces of the thin foils and hence to investigate the plastic flow through the samples. Attention was paid to the polarity (A or B) of the specimen surface, as GaAs is known to show a large difference between α and β dislocations mobilities. A model considering the influence of polarity is proposed to describe the material flow throughout thin samples

  3. Progressive evolution of microfabrics in high-temperature indentation creep experiments

    Science.gov (United States)

    Wassmann, S.; Dorner, D.; Stoeckhert, B.

    2014-12-01

    Microfabrics of natural rocks as well as of those deformed in laboratory experiments are studied post-mortem, the history of fabric evolution being inferred from a finite state. This is a major drawback when being interested in modification of fabrics related to progressive deformation. Here we present a novel approach to analyze and compare fabrics in different stages of evolution, taking spatial position to mimic a time series. Using this approach, evolution in time can be investigated on one sample deformed in a single indentation creep test. Such experiments at high temperatures and atmospheric pressure provide information on mechanical properties of rock-forming minerals as well as on microfabrics developed during inhomogeneous deformation underneath the indenter. Using a conventional creep apparatus, a cylindrical alumina indenter, 2 mm in diameter, is driven by a dead load into the flat surface of a specimen. A penetration depth of 1 mm is typically reached after hours to days, depending on material, applied temperature, and load. Previous experiments on natural, polycrystalline anhydrite carried out at temperatures between 700°C and 920 °C yield a stress exponent of 3.9 indicating deformation in the dislocation creep regime, consistent with microstructural observations (Dorner et al., 2014; Solid Earth). Within a cone-shaped region in front of the indenter, the original microfabric appears entirely unaffected. The neutral cone is mantled by highly deformed shear zones. During progressive indentation this structure of undeformed cone and shear zones propagates into the specimen. Thus, for a homogeneous starting material, serial sections of the deformed specimen normal to the indenter axis provide insight into fabrics in distinct stages of evolution. Microfabrics developed at different distance in front of the approaching indenter can be taken to represent a time series. A disadvantage of the technique is that the history of shear zone deformation is

  4. Sub-micron indent induced plastic deformation in copper and irradiated steel

    International Nuclear Information System (INIS)

    Robertson, Ch.

    1999-01-01

    In this work we aim to study the indent induced plastic deformation. For this purpose, we have developed a new approach, whereby the indentation curves provides the mechanical behaviour, while the deformation mechanisms are observed thanks to Transmission Electron Microscopy (TEM). In order to better understand how an indent induced dislocation microstructure forms, numerical modeling of the indentation process at the scale of discrete dislocations has been worked out as well. Validation of this modeling has been performed through direct comparison of the computed microstructures with TEM micrographs of actual indents in pure Cu (001]. Irradiation induced modifications of mechanical behaviour of ion irradiated 316L have been investigated, thanks to the mentioned approach. An important hardening effect was reported from indentation data (about 50%), on helium irradiated 316L steel. TEM observations of the damage zone clearly show that this behaviour is associated with the presence of He bubbles. TEM observations of the indent induced plastic zone also showed that the extent of the plastic zone is strongly correlated with hardness, that is to say: harder materials gets a smaller plastic zone. These results thus clearly established that the selected procedure can reveal any irradiation induced hardening in sub-micron thick ion irradiated layers. The behaviour of krypton irradiated 316L steel is somewhat more puzzling. In one hand indeed, a strong correlation between the defect cluster size and densities on the irradiation temperature is observed in the 350 deg. C - 600 deg. C range, thanks to TEM observations of the damage zone. On the other hand, irradiation induced hardening reported from indentation data is relatively small (about 10%) and shows no dependence upon the irradiation temperature (within the mentioned range). In addition, it has been shown that the reported hardening vanishes following appropriate post-irradiation annealing, although most of the TEM

  5. Poverty Underestimation in Rural India- A Critique

    OpenAIRE

    Sivakumar, Marimuthu; Sarvalingam, A

    2010-01-01

    When ever the Planning Commission of India releases the poverty data, that data is being criticised by experts and economists. The main criticism is underestimation of poverty especially in rural India by the Planning Commission. This paper focuses on that criticism and compares the Indian Planning Commission’s 2004-05 rural poverty data with the India’s 2400 kcal poverty norms, World Bank’s US $1.08 poverty concept and Asian Development Bank’s US $1.35 poverty concept.

  6. Pressure ulcers, indentation marks and pain from cervical spine immobilization with extrication collars and headblocks : An observational study

    NARCIS (Netherlands)

    Ham, Wietske H W; Schoonhoven, Lisette; Schuurmans, Marieke J; Leenen, Luke P H

    OBJECTIVES: To describe the occurrence and severity of pressure ulcers, indentation marks and pain from the extrication collar combined with headblocks. Furthermore, the influence of time, injury severity and patient characteristics on the development of pressure ulcers, indentation marks and pain

  7. Pressure ulcers, indentation marks and pain from cervical spine immobilization with extrication collars and headblocks: An observational study

    NARCIS (Netherlands)

    Ham, W.H.; Schoonhoven, L.; Schuurmans, M.J.; Leenen, L.P.

    2016-01-01

    OBJECTIVES: To describe the occurrence and severity of pressure ulcers, indentation marks and pain from the extrication collar combined with headblocks. Furthermore, the influence of time, injury severity and patient characteristics on the development of pressure ulcers, indentation marks and pain

  8. Female Poverty in Development Paradigm

    OpenAIRE

    PEKER, Ayşe Esra

    2018-01-01

    The scope  of  poverty differs  from country tocountry,  from the  period to period,  and  depending on  the  developments in welfare  level.  Today, although  the  phenomenon poverty is seen  the problem  of   less developed  and   developing c...

  9. Poverty, Dependence, Optimizing, and Adapting : Material and Spiritual Poverty

    NARCIS (Netherlands)

    Sarot, Marcel; Speelman, Willem Marie

    2017-01-01

    In the preparations of this project, there have been some serious objections against the approach of poverty as a spiritual path. Sarot argues that Christians should listen carefully to these criticisms, for ideals may easily cover up realities of evil, and, in response, contemplates the use of the

  10. Subducting an old subduction zone sideways provides insights into what controls plate coupling

    Science.gov (United States)

    Reyners, Martin; Eberhart-Phillips, Donna; Bannister, Stephen

    2017-05-01

    The Hikurangi Plateau has had two episodes of subduction beneath New Zealand - firstly at ca. 100 Ma during north-south convergence with Gondwana, and currently during east-west convergence between the Pacific and Australian plates. As a result of this ninety-degree change in convergence direction, an old subduction zone is now being subducted sideways, and the tectonic history of the subducted plate varies dramatically along the strike of the Hikurangi Margin. Here we identify the location of the underplated Hikurangi Plateau along the shallow part of the Hikurangi Margin, using results from both relocated seismicity and seismic tomography. Next we decipher the tectonic history of the plateau along strike, particularly in terms of the hydration state of the plateau, and the nature of any sedimentary rock units capping the plateau. We then use this information to understand plate coupling at two scales: on the large scale, the southward transition from typical subduction in the North Island to continental collision in the South Island; and at a smaller scale, the strong lateral change from a high deficit in slip rate at the plate interface in the southern North Island to a low deficit in slip rate in the northeastern North Island. We find that the southward transition from subduction to continental collision is controlled by the plateau being more dehydrated to the south, as a result of being more deeply subducted at the Gondwana margin. The southward transition from localized slip at the plate interface to distributed upper plate deformation with no active plate interface occurs in Cook Strait and is relatively sharp. The high deficit in slip rate at the plate interface in the southern North Island is likely due to a relatively smooth plate interface from sedimentary rocks capping the Hikurangi Plateau, an impermeable terrane in the overlying plate, and the hydrated plateau acting in concert to produce an interseismically sealed plate interface. Further northeast

  11. Deformation and strain distribution in plasma sprayed nickel-aluminum coating loaded by a spherical indenter

    Czech Academy of Sciences Publication Activity Database

    Prchlík, L.; Písačka, Jan; Sampath, S.

    2003-01-01

    Roč. 360, 1-2 (2003), s. 264-274 ISSN 0921-5093 R&D Projects: GA AV ČR KSK1010104 Keywords : indentation, stress-strain relationship, plasma spray Subject RIV: JJ - Other Materials Impact factor: 1.365, year: 2003

  12. Determination of the individual phase properties from the measured grid indentation data

    Czech Academy of Sciences Publication Activity Database

    Haušild, P.; Materna, A.; Kocmanová, L.; Matějíček, Jiří

    2016-01-01

    Roč. 31, č. 22 (2016), s. 3538-3548 ISSN 0884-2914 R&D Projects: GA ČR GB14-36566G Institutional support: RVO:61389021 Keywords : Composite * Tungsten * Steel * indentation Subject RIV: JI - Composite Materials Impact factor: 1.673, year: 2016 http://dx. doi . org /10.1557/jmr.2016.375

  13. Assessment with indentation techniques of the local mechanical behavior of joints in polymer parts

    Czech Academy of Sciences Publication Activity Database

    Lach, R.; Hutař, Pavel; Veselý, P.; Nezbedová, E.; Knésl, Zdeněk; Koch, T.; Bierogel, C.; Grellmann, W.

    2013-01-01

    Roč. 58, 11-12 (2013), s. 900-905 ISSN 0032-2725 R&D Projects: GA ČR GC101/09/J027 Institutional support: RVO:68081723 Keywords : weld ed joints * weld lines * microindentation techniques * nanoindentation techniques * hardness * indentation modulus Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.617, year: 2013

  14. Interference of lithospheric folding in western Central Asia by simultaneous Indian and Arabian plate indentation

    NARCIS (Netherlands)

    Smit, J.W.H.; Cloetingh, S.A.P.L.|info:eu-repo/dai/nl/069161836; Burov, E.; Tesauro, M.; Sokoutis, D.|info:eu-repo/dai/nl/298809214; Kaban, M.

    2013-01-01

    Large-scale intraplate deformation of the crust and the lithosphere in Central Asia as a result of the indentation of India has been extensively documented. In contrast, the impact of continental collision between Arabia and Eurasia on lithosphere tectonics in front of the main suture zone, has

  15. Interference of lithospheric folding in Central Asia by simultaneous Indian and Arabian plate indentation

    NARCIS (Netherlands)

    Smit, J.H.W.; Cloetingh, S.A.P.L.; Burov, E.; Tesauro, M.; Sokoutis, D.; Kaban, M.K.

    2013-01-01

    Large-scale intraplate deformation of the crust and the lithosphere in Central Asia as a result of the indentation of India has been extensively documented. In contrast, the impact of continental collision between Arabia and Eurasia on lithosphere tectonics in front of the main suture zone, has

  16. Indentation creep of heterogeneous blends poly(ethylene terephthalate)/impact modifier

    Czech Academy of Sciences Publication Activity Database

    Kolařík, Jan; Pegoretti, A.

    2004-01-01

    Roč. 23, č. 1 (2004), s. 113-121 ISSN 0142-9418 R&D Projects: GA ČR GA106/00/1307 Institutional research plan: CEZ:AV0Z4050913 Keywords : indentation creep * thermoplastics * polymer blends Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.199, year: 2004

  17. Residual stress evaluation in brittle coatings using indentation technique combined with in-situ bending

    International Nuclear Information System (INIS)

    Futakawa, Masatoshi; Steinbrech, R.W.; Tanabe, Yuji; Hara, Toshiaki

    2000-01-01

    The indentation crack length approach was adopted and further elaborated to evaluate residual stress and toughness of the brittle coatings: two kinds of glass coatings on steel. The influence of the residual stress on indentation cracking was examined in as-received coating condition and by in-situ superimposing a counteracting tensile stress. For purpose of providing reference toughness values stress-free pieces of separated coating material have also been examined. Thus results of the two complementary sets of experiments were assumed to prove self-consistently toughness and residual stress data of the coating. In particular, the in-situ bending of specimen in combination with the indentation test allowed us to vary deliberately the residual stress situation in glass coating. Thus experiments which utilized the combination of bending test and micro-indentation were introduced as a method to provide unambiguous information about residual compressive stress. Toughness and residual compressive stress of glass coatings used in this study were 0.46-0.50 MPa·m 1/2 and 94-111 MPa, respectively. Furthermore, a thermoelastic calculation of the residual compressive stress was performed and it is found that the value of residual compressive stress at coating surface of specimen was 90-102 MPa. (author)

  18. Mechanical properties of gray and white matter brain tissue by indentation.

    Science.gov (United States)

    Budday, Silvia; Nay, Richard; de Rooij, Rijk; Steinmann, Paul; Wyrobek, Thomas; Ovaert, Timothy C; Kuhl, Ellen

    2015-06-01

    The mammalian brain is composed of an outer layer of gray matter, consisting of cell bodies, dendrites, and unmyelinated axons, and an inner core of white matter, consisting primarily of myelinated axons. Recent evidence suggests that microstructural differences between gray and white matter play an important role during neurodevelopment. While brain tissue as a whole is rheologically well characterized, the individual features of gray and white matter remain poorly understood. Here we quantify the mechanical properties of gray and white matter using a robust, reliable, and repeatable method, flat-punch indentation. To systematically characterize gray and white matter moduli for varying indenter diameters, loading rates, holding times, post-mortem times, and locations we performed a series of n=192 indentation tests. We found that indenting thick, intact coronal slices eliminates the common challenges associated with small specimens: it naturally minimizes boundary effects, dehydration, swelling, and structural degradation. When kept intact and hydrated, brain slices maintained their mechanical characteristics with standard deviations as low as 5% throughout the entire testing period of five days post mortem. White matter, with an average modulus of 1.89 5kPa ± 0.592 kPa, was on average 39% stiffer than gray matter, pmatter and responded less rapidly to mechanical loading. Understanding the rheological differences between gray and white matter may have direct implications on diagnosing and understanding the mechanical environment in neurodevelopment and neurological disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Articular cartilage response to a sliding load using two different-sized spherical indenters1.

    Science.gov (United States)

    Schätti, Oliver R; Colombo, Vera; Torzilli, Peter A; Gallo, Luigi M

    2018-01-01

    Cartilage surface contact geometry influences the deformational behavior and stress distribution throughout the extracellular matrix (ECM) under load. To test the correlation between the mechanical and cellular response of articular cartilage when loaded with two different-sized spherical indenters under dynamic reciprocating sliding motion. Articular cartilage explants were subjected to a reciprocating sliding load using a 17.6 mm or 30.2 mm spherical ball for 2000 cycles at 10 mm/s and 4 kg axial load. Deformation of the cartilage was recorded and contact parameters were calculated according to Hertzian theory. After mechanical loading cartilage samples were collected and analyzed for ECM collagen damage, gene regulation and proteoglycan (PG) loss. Significantly higher ECM deformation and strain and lower dynamic effective modulus were found for explants loaded with the smaller diameter indenter whereas contact radius and stress remained unaffected. Also, the 17.6 mm indenter increased PG loss and significantly upregulated genes for ECM proteins and enzymes as compared to the 30.2 mm indenter. Sliding loads that increase ECM deformation/strain were found to induce enzyme-mediated catabolic processes in articular cartilage explants. These observations provide further understanding of how changes in cartilage contact mechanics under dynamic conditions can affect the cellular response.

  20. Material Flow Analysis in Indentation by Two-Dimensional Digital Image Correlation and Finite Elements Method.

    Science.gov (United States)

    Bermudo, Carolina; Sevilla, Lorenzo; Castillo López, Germán

    2017-06-21

    The present work shows the material flow analysis in indentation by the numerical two dimensional Finite Elements (FEM) method and the experimental two-dimensional Digital Image Correlation (DIC) method. To achieve deep indentation without cracking, a ductile material, 99% tin, is used. The results obtained from the DIC technique depend predominantly on the pattern conferred to the samples. Due to the absence of a natural pattern, black and white spray painting is used for greater contrast. The stress-strain curve of the material has been obtained and introduced in the Finite Element simulation code used, DEFORM™, allowing for accurate simulations. Two different 2D models have been used: a plain strain model to obtain the load curve and a plain stress model to evaluate the strain maps on the workpiece surface. The indentation displacement load curve has been compared between the FEM and the experimental results, showing a good correlation. Additionally, the strain maps obtained from the material surface with FEM and DIC are compared in order to validate the numerical model. The Von Mises strain results between both of them present a 10-20% difference. The results show that FEM is a good tool for simulating indentation processes, allowing for the evaluation of the maximum forces and deformations involved in the forming process. Additionally, the non-contact DIC technique shows its potential by measuring the superficial strain maps, validating the FEM results.

  1. Crystalline cellulose elastic modulus predicted by atomistic models of uniform deformation and nanoscale indentation

    Science.gov (United States)

    Xiawa Wu; Robert J. Moon; Ashlie Martini

    2013-01-01

    The elastic modulus of cellulose Iß in the axial and transverse directions was obtained from atomistic simulations using both the standard uniform deformation approach and a complementary approach based on nanoscale indentation. This allowed comparisons between the methods and closer connectivity to experimental measurement techniques. A reactive...

  2. Measurement of time-dependent adhesion between a polymer film and a flat indenter tip

    International Nuclear Information System (INIS)

    Choi, S T; Lee, S R; Earmme, Y Y

    2008-01-01

    We revisited an elasticity problem of flat indentation on an elastic film bonded to a rigid substrate and obtained the force-depth relation in a simple form. With the obtained force-depth relation, Kendall's elastic equilibrium theory of adhesion was extended to the adhesion between a flat tip and a compressible elastic film. Thus, the thermodynamic work of adhesion at the moment of debonding of a flat tip from an elastic film was expressed in terms of pull-off force, elastic constants and geometric parameters. It is worth noting that the obtained relation for elastic films is still valid for viscoelastic films if viscoelastic losses are limited to the process zone of debonding. This makes it possible to study the time-dependent adhesion of viscoelastic polymer films. Indentation experiments with a flat diamond tip were performed on SU-8 films, and the results verified that the extended form of Kendall's theory correctly compensates the effect of the finite thickness of the films on the work of adhesion. The indentation results also showed that the work of adhesion is strongly dependent on the unloading velocity of the tip, while indentation depth and dwell time have only minor effects on the work of adhesion

  3. Mechanical damage in a lithium-ion pouch cell under indentation loads

    Science.gov (United States)

    Luo, Hailing; Xia, Yong; Zhou, Qing

    2017-07-01

    The short circuit of lithium-ion batteries induced by mechanical abuse is a great concern in electric vehicle design. It remains a challenge to fully understand the nature of the mechanical damage process with the aim of improving battery crash safety. The present paper investigates the evolution of the damage process for a lithium-ion pouch cell under indentation by loading the cell to various force levels. A significant inflection point on the force-indentation curve is observed before the force peak. Post-mortem examinations indicate that the characteristic change in the local slope of the curve is related to the change occurring at the local interfaces, including three phenomena - formation of tight adhesion on the anode-separator interfaces, delamination in the separators and decoating of graphite particles from the anodes. Analysis of the fracture sequence at the onset of short circuit clearly shows that the number of short-circuited electrode pairs is equal to the number of anode layers adhered with delaminated separator material before fracture occurs. The experimental study in the present paper implies that the inflection point on the force-indentation curve may be an indicator of damage initiation inside pouch cells under indentation.

  4. A Progressive Damage Model for Predicting Permanent Indentation and Impact Damage in Composite Laminates

    Science.gov (United States)

    Ji, Zhaojie; Guan, Zhidong; Li, Zengshan

    2017-10-01

    In this paper, a progressive damage model was established on the basis of ABAQUS software for predicting permanent indentation and impact damage in composite laminates. Intralaminar and interlaminar damage was modelled based on the continuum damage mechanics (CDM) in the finite element model. For the verification of the model, low-velocity impact tests of quasi-isotropic laminates with material system of T300/5228A were conducted. Permanent indentation and impact damage of the laminates were simulated and the numerical results agree well with the experiments. It can be concluded that an obvious knee point can be identified on the curve of the indentation depth versus impact energy. Matrix cracking and delamination develops rapidly with the increasing impact energy, while considerable amount of fiber breakage only occurs when the impact energy exceeds the energy corresponding to the knee point. Predicted indentation depth after the knee point is very sensitive to the parameter μ which is proposed in this paper, and the acceptable value of this parameter is in range from 0.9 to 1.0.

  5. Dynamics of interplate domain in subduction zones: influence of rheological parameters and subducting plate age

    Directory of Open Access Journals (Sweden)

    D. Arcay

    2012-12-01

    Full Text Available The properties of the subduction interplate domain are likely to affect not only the seismogenic potential of the subduction area but also the overall subduction process, as it influences its viability. Numerical simulations are performed to model the long-term equilibrium state of the subduction interplate when the diving lithosphere interacts with both the overriding plate and the surrounding convective mantle. The thermomechanical model combines a non-Newtonian viscous rheology and a pseudo-brittle rheology. Rock strength here depends on depth, temperature and stress, for both oceanic crust and mantle rocks. I study the evolution through time of, on one hand, the brittle-ductile transition (BDT depth, zBDT, and, on the other hand, of the kinematic decoupling depth, zdec, simulated along the subduction interplate. The results show that both a high friction and a low ductile strength at the asthenospheric wedge tip shallow zBDT. The influence of the weak material activation energy is of second order but not negligible. zBDT becomes dependent on the ductile strength increase with depth (activation volume if the BDT occurs at the interplate decoupling depth. Regarding the interplate decoupling depth, it is shallowed (1 significantly if mantle viscosity at asthenospheric wedge tip is low, (2 if the difference in mantle and interplate activation energy is weak, and (3 if the activation volume is increased. Very low friction coefficients and/or low asthenospheric viscosities promote zBDT = zdec. I then present how the subducting lithosphere age affects the brittle-ductile transition depth and the kinematic decoupling depth in this model. Simulations show that a rheological model in which the respective activation energies of mantle and interplate material are too close hinders the mechanical decoupling at the down-dip extent of the interplate

  6. Community Awareness and Participation in Poverty Reduction ...

    African Journals Online (AJOL)

    poverty policies and strategies. Consistent with this, the government of Tanzania is determined to encourage bottom-up participatory planning with focus on the objectives of poverty alleviation. Despite the importance of community participation ...

  7. Global subduction volume fluxes over the past 200 Ma

    Science.gov (United States)

    Heine, C.; Butterworth, N. P.; Quevedo, L. E.; Müller, D.

    2013-12-01

    The volume of subducted oceanic lithosphere changes over geological time as seafloor of different mean age distributions is subducted at with different rates. This has potential implications for the spatio-temporal dynamics of mantle convection and especially dynamic topography induced by negatively buoyant material in the mantle as well as the time-dependence of the related mantle return flow. We use global plate kinematic models and paleooceanic age grids to analyse the subduction volume fluxes over the past 200 Million years and compare our results with global mantle convection models and observations from seismic tomography and key regions which are known to have experienced significant changes in vertical motions due to mantle convection-induced dynamic topography. Two distinct patterns of subduction are found related to the motion of the overriding plate: a localised volume flux, characteristic for relatively stationary subduction around southern and eastern Eurasia and a widely distributed volume flux, predominately for the North and South American Pacific subduction zones where oceanic slabs of varying age have been subducted over wide regions. Subduction zones around Antarctica and the SW Pacific range between both end-members types. We find that the global subduction volume flux decreases substantially from a peak with of around 6.5*10^6 km^3/Myr around the Base Cretaceous to volumes fluxes of around 3.0*10^6 km^3/Myr, reflecting a long-term decrease in oceanic crustal production. In addition we find peaks in global subduction volume flux around 125, 55 and 20 Ma, whose origin can be related to the regional evolution of particular subduction systems.

  8. Tobacco and poverty A Vicious Circle

    OpenAIRE

    Tobacco Free Initiative

    2004-01-01

    Tobacco and poverty: a vicious circle The contribution of tobacco to premature death and disease is well documented. However,little attention has been paid to the link between tobacco and poverty. Tobacco tends to be consumed by those who are poorer. In turn, it contributes to poverty through loss of income,loss of productivity, disease and death. Together, tobacco and poverty form a vicious circle from which it is often difficult to escape.

  9. Poverty eradication in a carbon constrained world

    OpenAIRE

    Hubacek, Klaus; Baiocchi, Giovanni; Feng, Kuishuang; Patwardhan, Anand

    2017-01-01

    The UN Framework Convention on Climate Change aims to keep warming below 2 °C while recognizing developing countries’ right to eradicate extreme poverty. Poverty eradication is also the first of the Sustainable Development Goals. This paper investigates potential consequences for climate targets of achieving poverty eradication. We find that eradicating extreme poverty, i.e., moving people to an income above $1.9 purchasing power parity (PPP) a day, does not jeopardize the climate target even...

  10. Education for the Eradication of Poverty

    OpenAIRE

    C.I. Oriahi; A.O. Aitufe

    2010-01-01

    This study examines the possible education for the eradication of poverty in Nigeria. It defines poverty as a state pf shortage or deficiency of meeting basic needs. Majors causes of poverty are overpopulation, illiteracy, unemployment, environmental degradation and government insensitive to the welfare of the people. Effects of poverty include homelessness, malnutrition and starvation, illness, crime, violence and antisocial behaviour like Internet Fraud (Yahoo business) and Advance Fee Frau...

  11. Climate change and poverty -- an analytical framework

    OpenAIRE

    Hallegatte, Stephane; Bangalore, Mook; Bonzanigo, Laura; Fay, Marianne; Narloch, Ulf; Rozenberg, Julie; Vogt-Schilb, Adrien

    2014-01-01

    Climate change and climate policies will affect poverty reduction efforts through direct and immediate impacts on the poor and by affecting factors that condition poverty reduction, such as economic growth. This paper explores this relation between climate change and policies and poverty outcomes by examining three questions: the (static) impact on poor people's livelihood and well-being; the impact on the risk for non-poor individuals to fall into poverty; and the impact on the ability of po...

  12. Poverty and Vulnerability - An Interdisciplinary Approach

    OpenAIRE

    Makoka, Donald; Kaplan, Marcus

    2005-01-01

    This paper describes the concepts of poverty and vulnerability as well as the interconnections and differences between them using an interdisciplinary approach. While poverty is a static concept, vulnerability has a forward-looking dimension. We, therefore, review the methodologies that different disciplines use to measure poverty and vulnerability. In particular, the differences between vulnerability to natural disasters, vulnerability to climate change, as well as vulnerability to poverty a...

  13. An Asian poverty line? Issues and options

    OpenAIRE

    Klasen, Stephan

    2016-01-01

    Given Asia's record of rapid economic growth and the conceptual and empirical problems of the current international income poverty line ('dollar-a-day'), this paper discusses whether there is merit to develop an Asia-specific poverty line that addresses some of the shortcomings of the dollar-a-day line and additionally considers Asia's particular economic situation. We consider various ways of creating an Asia-specific poverty line, including an Asia-specific international income poverty line...

  14. The Future of American Poverty; Some Basic Issues in Evaluating Alternative Anti-Poverty Measures.

    Science.gov (United States)

    Berry, Paul C.; And Others

    Embracing four separate reports, this document contains a context and summary for studying orientations toward poverty, kinds of poor, and other basic issues of poverty; equality of economic opportunity and other criteria for evaluating poverty programs; general solutions to poverty; characteristics of transfer payment systems, birth control, and…

  15. Subjective Poverty and Its Relation to Objective Poverty Concepts in Hungary

    Science.gov (United States)

    Nandori, Eszter Siposne

    2011-01-01

    The paper analyzes subjective poverty in Hungary and compares it to the objective poverty concepts. Subjective poverty is defined by examining who people consider to be poor. Based on the Easterlin paradox, the initial hypothesis states that subjective and absolute poverty concepts are highly correlated. Taking into account that Hungary is a…

  16. First-principles calculation of the indentation strength of FeB4

    Science.gov (United States)

    Li, Bing; Sun, Hong; Chen, Changfeng

    2014-07-01

    A recent experiment [H. Y. Gou et al., Phys. Rev. Lett. 111, 157002 (2013), 10.1103/PhysRevLett.111.157002] reported a measured Vickers hardness of over 60 GPa for FeB4, placing it as a superhard material far above all other similar ultrahard transition-metal borides, such as ReB2,WB4, and especially CrB4, which has the same crystalline structure as that of FeB4 but a much lower measured Vickers hardness of around 23 GPa. This result, however, is contradicted by theoretical calculations that predict a smaller shear modulus for FeB4 than that of CrB4, indicating that FeB4 is softer than CrB4. Here we report first-principles calculations that aim to understand the stress response of FeB4 under indentation loadings and examine whether there exists a strain-stiffening effect that might enhance the indentation strength. Our results show that there is no strain stiffening in FeB4; instead, the normal pressure beneath the indenter drives a lateral structural expansion which further stretches and weakens the boron-boron and boron-iron bonds in addition to that caused by the shear deformation in Vickers indentation tests. This effect leads to a considerably reduced strength of FeB4, producing an ideal (i.e., an upper bound) indentation strength of 17 GPa that is lower than that (27 GPa) predicted for CrB4. The present results suggest that FeB4 is unlikely to be superhard and further experimental investigation is needed to clarify this issue.

  17. Identification of the crushing behavior of brittle foam: From indentation to oedometric tests

    Science.gov (United States)

    Bouterf, A.; Adrien, J.; Maire, E.; Brajer, X.; Hild, F.; Roux, S.

    2017-01-01

    Compaction of the core of plasterboard is one of the limiting phenomena for its mechanical performance. This mechanism is studied herein in an indentation test. A cylinder made of foamed gypsum is indented in situ in an X-ray lab tomograph with a sphere of millimeter radius. The reported experiments show that foamed plaster displays a sharp transition between an undamaged state (with linear elastic behavior) and a compacted state with collapsed porosity under the indenter. Tomographic acquisitions of the sample under load associated with a global version of Digital Volume Correlation allow displacement fields to be measured at different load levels. However, because of the heterogeneous nature of the indentation test, a fine spatial resolution of the displacement fields is required to measure the strains at the crushing limit. A dedicated procedure exploiting computed displacement fields within the digital volume correlation procedure is utilized. It allows for the quantification of stress fields that are post-processed to identify the crushing criterion. It is shown that this analysis is very consistent with more macroscopic oedometric tests. Last, predictions of a Mohr-Coulomb model are compared with macroscopic and microscopic data. It is shown that despite the fact that this model reproduces very well the load-displacement response of the indentation test, a poorer prediction of the experimental crushed zone is observed. In particular, the transition between compacted plaster and its pristine state is not captured by the model, which predicts a very progressive transition rather than an abrupt one. The same conclusions are drawn for a crushable foam model when compared with experimental evidence of an in situ oedometric test.

  18. Modeling ramp-hold indentation measurements based on Kelvin-Voigt fractional derivative model

    Science.gov (United States)

    Zhang, Hongmei; zhe Zhang, Qing; Ruan, Litao; Duan, Junbo; Wan, Mingxi; Insana, Michael F.

    2018-03-01

    Interpretation of experimental data from micro- and nano-scale indentation testing is highly dependent on the constitutive model selected to relate measurements to mechanical properties. The Kelvin-Voigt fractional derivative model (KVFD) offers a compact set of viscoelastic features appropriate for characterizing soft biological materials. This paper provides a set of KVFD solutions for converting indentation testing data acquired for different geometries and scales into viscoelastic properties of soft materials. These solutions, which are mostly in closed-form, apply to ramp-hold relaxation, load-unload and ramp-load creep-testing protocols. We report on applications of these model solutions to macro- and nano-indentation testing of hydrogels, gastric cancer cells and ex vivo breast tissue samples using an atomic force microscope (AFM). We also applied KVFD models to clinical ultrasonic breast data using a compression plate as required for elasticity imaging. Together the results show that KVFD models fit a broad range of experimental data with a correlation coefficient typically R 2  >  0.99. For hydrogel samples, estimation of KVFD model parameters from test data using spherical indentation versus plate compression as well as ramp relaxation versus load-unload compression all agree within one standard deviation. Results from measurements made using macro- and nano-scale indentation agree in trend. For gastric cell and ex vivo breast tissue measurements, KVFD moduli are, respectively, 1/3-1/2 and 1/6 of the elasticity modulus found from the Sneddon model. In vivo breast tissue measurements yield model parameters consistent with literature results. The consistency of results found for a broad range of experimental parameters suggest the KVFD model is a reliable tool for exploring intrinsic features of the cell/tissue microenvironments.

  19. Poverty among Elderly in India

    Science.gov (United States)

    Srivastava, Akanksha; Mohanty, Sanjay K.

    2012-01-01

    Using consumption expenditure data of the National Sample Survey 2004-2005, this paper estimates the size of elderly poor and tests the hypotheses that elderly households are not economically better-off compared to non-elderly households in India. Poverty estimates are derived under three scenarios--by applying the official cut-off point of the…

  20. Population, Poverty, and Climate Change

    OpenAIRE

    Monica Das Gupta

    2014-01-01

    The literature is reviewed on the relationships between population, poverty, and climate change. While developed countries are largely responsible for global warming, the brunt of the fallout will be borne by the developing world, in lower agricultural output, poorer health, and more frequent natural disasters. Carbon emissions in the developed world have leveled off, but are projected to ...

  1. Informal export barriers and poverty

    OpenAIRE

    Porto, Guido G.

    2004-01-01

    The author investigates the poverty impacts of informal export barriers like transport costs, cumbersome customs practices, costly regulations, and bribes. He models these informal barriers as export taxes that distort the efficient allocation of resources. In low-income agricultural economies, this distortion lowers wages and household agricultural income, thereby leading to higher pover...

  2. The elusive constellations of poverty

    NARCIS (Netherlands)

    Breugelmans, S.M.; Plantinga, A.; Zeelenberg, M.; Poluektova, Olga; Efremova, Maria

    2018-01-01

    Pepper & Nettle describe possible processes underlying what they call a behavioral constellation of deprivation (BCD). Although we are certain about the application of evolutionary models to our understanding of poverty, we are less certain about the utility of behavioral constellations. The

  3. Race, Poverty, and Teacher Mobility

    Science.gov (United States)

    Scafidi, Benjamin; Sjoquist, David L.; Stinebrickner, Todd R.

    2007-01-01

    This paper provides information about the importance of non-pecuniary school characteristics, such as race and poverty, on teacher turnover in Georgia. Simple descriptive statistics indicate that new teachers are more likely to leave schools with lower test scores, lower income, or higher proportions of minorities. A linear probability and a…

  4. Determinant of Poverty in Ethiopia

    African Journals Online (AJOL)

    preferred customer

    analyze the impact of socioeconomic and demographic characteristics of households on poverty in Ethiopia, using the latest Household Income,. Consumption and Expenditure Survey (HICES) 2010-11. The study employs a logistic regression model to identify determinants of wellbeing of the household by considering per ...

  5. Climate Change, Agriculture, and Poverty

    OpenAIRE

    Thomas W. Hertel; Stephanie D. Rosch

    2010-01-01

    Although much has been written about climate change and poverty as distinct and complex problems, the link between them has received little attention. Understanding this link is vital for the formulation of effective policy responses to climate change. This paper focuses on agriculture as a primary means by which the impacts of climate change are transmitted to the poor, and as a sector at...

  6. Child poverty and environmental justice.

    Science.gov (United States)

    Hornberg, Claudia; Pauli, Andrea

    2007-10-01

    Child poverty and social inequality in Western countries are growing both in scope and in complexity. The clustering of income poverty in urban settings reflects the complex process of residential segregation. Living in segregated neighbourhoods with much poverty and predominantly substandard housing is usually associated with poor physical, chemical and social environmental living conditions at the individual and community level which influence and shape children's health both directly and indirectly. This paper shows research data on the link between child poverty and income-related health inequalities according to the unequal exposure to environmental hazards as well as the unequal distribution of environmental resources in the domestic environment and within the local context as an increasing public health issue in Germany. The links between these factors are drawn from the conceptual framework of environmental justice. Examples are shown of integrated approaches to alleviate social and environmental disparities at the community level. The implications of environmental justice for public health include the need to uncover the link between socioeconomic factors and environmental health disparities related to the man-made environment. Developing relevant indicators for environmental inequalities in the context of housing and health is an important task for public health research. More emphasis should be placed on a comprehensive holistic approach to understand the mechanisms by which socioeconomic factors modify children's susceptibility and exposure to environmental hazards, particularly in low-income areas.

  7. Examining the Culture of Poverty: Promising Practices

    Science.gov (United States)

    Cuthrell, Kristen; Stapleton, Joy; Ledford, Carolyn

    2009-01-01

    Spurred by preservice teachers' perceptions that diversity issues such as poverty would not affect their teaching, professors in 1 southeastern U.S. elementary teacher-preparation program took action, which resulted in this examination of the culture of poverty and the identification of strategies to best serve children living in poverty. The…

  8. The Effects of Poverty on Academic Achievement

    Science.gov (United States)

    Lacour, Misty; Tissington, Laura D.

    2011-01-01

    Poverty, which forms a specific culture and way of life, is a growing issue in the United States. The number of Americans living in poverty is continually increasing. Poverty indicates the extent to which an individual does without resources. Resources can include financial, emotional, mental, spiritual, and physical resources as well as support…

  9. Growth and poverty reduction in Tanzania

    DEFF Research Database (Denmark)

    Arndt, Channing; Demery, Lionel; McKay, Andy

    . The household survey data documents a limited reduction in consumption poverty over the period, and what poverty reduction there has been has mostly occurred in Dar es Salaam. Indicators of non-monetary poverty have gradually improved over the past 20 years but significant differences across the country remain....

  10. Energy poverty, shack fires and childhood burns

    African Journals Online (AJOL)

    Deepening of energy poverty in South. Africa. Energy poverty, i.e. the lack of access to modern energy, is a key driver of burn injury in South Africa (SA). Energy poverty is prevalent in dense low-income settlements in developing countries, including SA.[1-4] The dirty fuels that the energy-poor depend on are burnt in ...

  11. Climate Change and Poverty : An Analytical Framework

    OpenAIRE

    Hallegatte, Stephane; Bonzanigo, Laura; Narloch, Ulf; Vogt-Schilb, Adrien; Rozenberg, Julie; Fay, Marianne; Bangalore, Mook

    2014-01-01

    Climate change and climate policies will affect poverty reduction efforts through direct and immediate impacts on the poor and by affecting factors that condition poverty reduction, such as economic growth. This paper explores this relation between climate change and policies and poverty outcomes by examining three questions: the (static) impact on poor people's livelihood and well-being; ...

  12. Declining poverty, rising inequality | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-07-08

    Jul 8, 2011 ... In three decades of rapid economic growth, China has lifted hundreds of millions of people out of poverty. The World Bank says the number living in extreme poverty fell from 64% of the population in 1978 to 4% – or 53 million people – in 2007. China calculates poverty differently and, by its yardstick, ...

  13. Development theory and poverty. A review

    OpenAIRE

    Francesco Farina

    2015-01-01

    This review article presents the evolution of development theory during the XX century, the measurement of poverty, the concept and the indices of multidimensional poverty. A special focus concerns the complex linkages between income inequality, poverty and institutions during the growth process of developing countries.

  14. Poverty Dynamics: the case of the Maldives

    NARCIS (Netherlands)

    J.L. de Kruijk (Hans)

    2010-01-01

    textabstractPoverty dynamics research leads to a better understanding of poverty than point-in-time studies. We have executed a comprehensive longitudinal poverty study based on 3 large-scale household surveys carried out on all 200 inhabited islands in the Maldives. The first wave was conducted in

  15. Fighting poverty and exclusion through social investment

    DEFF Research Database (Denmark)

    Kvist, Jon

    The fight against poverty and social exclusion is at the heart of the Europe 2020 strategy for smart, sustainable and inclusive growth. With more than 120 million people in the EU at risk of poverty or social exclusion, EU leaders have pledged to bring at least 20 million people out of poverty an...

  16. Gender and Poverty Reduction: A Kenyan Context

    Science.gov (United States)

    Kimani, Elishiba Njambi; Kombo, Donald Kisilu

    2010-01-01

    Poverty is a dehumanising condition for every one. It erodes human rights of the affected whether women or men. Poverty subjects an individual to a state of powerlessness, hopelessness, and lack of self-esteem, confidence, and integrity, leading to a situation of multidimensional vulnerability. Poverty has a gender dimension since women and men…

  17. The Poverty Impacts of Climate Change

    OpenAIRE

    Brahmbhatt, Milan; Skoufias, Emmanuel; Olivieri, Sergio; Rabassa, Mariano

    2011-01-01

    Over the last century, the world has seen a sustained decline in the proportion of people living in poverty. However, there is an increasing concern that climate change could slow or possibly even reverse poverty reduction progress. Given the complexities involved in analyzing climate change impacts on poverty, different approaches can be helpful; this note surveys the results of recent re...

  18. Law's Poverty | Modiri | Potchefstroom Electronic Law Journal ...

    African Journals Online (AJOL)

    Given their centrality in political and social discourse and in legal scholarship on poverty, it is worth considering whether and to what extent rights can be utilised in the struggle against (racialised) poverty. KEYWORDS: racialised poverty; oppression; imaginary domain; precarity; theories of justice; rights discourse; critical ...

  19. Levels of poverty and the poverty gap in rural Limpopo

    Directory of Open Access Journals (Sweden)

    R. R. Mears

    2010-12-01

    Full Text Available Purpose/objectives: The aim of this paper is to obtain a better understanding of the income and expenditure patterns of selected deep rural villages. This is done by measuring the level of poverty and/or the poverty gap of 132 households in Limpopo, one of the poorest provinces in South Africa. Problem investigated: The Millennium Declaration symbolises the commitment to end extreme poverty, but limited data is available for rural areas to inform policy decisions. The relative income shares for individuals, households and percentile groups within a population provide the best information on poverty for policy formulation. The nature and size distribution of income are therefore central to analysing the poverty problem within low-income areas. The survey area is one of the poorest areas in South Africa, and shows what data is needed to measure and understand the extent of poverty. Design/Method/Approach: A representative sample of 132 households was drawn, which represents 6,9 percent of the estimated 1900 households in selected villages of rural Limpopo. A total of 740 household members were represented in the survey, with an average of 5,6 members per household. Originality/Value: Although this is a relatively small sample, it generated much-needed data on this very poor area of South Africa. Detailed empirical data on the income and expenditure patterns is not available, especially for rural areas. The socio-economic data from this research supported an important health project of the Water and Health Research Unit (WHRU of the University of Johannesburg. The article also lays the foundation for further research in this field of study, facilitating engagement with a number of related debates such as those about satisfaction of life, vulnerability to poverty, the geography of deprivation and the mapping of poverty. Conclusion: The main finding is that the government provides for many needs of the poor, especially in the deep rural areas. Only

  20. Earthquake nucleation in weak subducted carbonates

    Science.gov (United States)

    Kurzawski, Robert M.; Stipp, Michael; Niemeijer, André R.; Spiers, Christopher J.; Behrmann, Jan H.

    2016-09-01

    Ocean-floor carbonate- and clay-rich sediments form major inputs to subduction zones, especially at low-latitude convergent plate margins. Therefore, knowledge of their frictional behaviour is fundamental for understanding plate-boundary earthquakes. Here we report results of mechanical tests performed on simulated fault gouges prepared from ocean-floor carbonates and clays, cored during IODP drilling offshore Costa Rica. Clay-rich gouges show internal friction coefficients (that is, the slope of linearized shear stress versus normal stress data) of μint = 0.44 - 0.56, irrespective of temperature and pore-fluid pressure (Pf). By contrast, μint for the carbonate gouge strongly depends on temperature and pore-fluid pressure, with μint decreasing dramatically from 0.84 at room temperature and Pf = 20 MPa to 0.27 at T = 140 °C and Pf = 120 MPa. This effect provides a fundamental mechanism of shear localization and earthquake generation in subduction zones, and makes carbonates likely nucleation sites for plate-boundary earthquakes. Our results imply that rupture nucleation is prompted by a combination of temperature-controlled frictional instability and temperature- and pore-pressure-dependent weakening of calcareous fault gouges.

  1. MODELLING OF POSTSEISMIC PROCESSES IN SUBDUCTION ZONES

    Directory of Open Access Journals (Sweden)

    Irina S. Vladimirova

    2012-01-01

    Full Text Available Large intraplate subduction earthquakes are generally accompanied by prolonged and intense postseismic anomalies. In the present work, viscoelastic relaxation in the upper mantle and the asthenosphere is considered as a main mechanism responsible for the occurrence of such postseismic effects. The study of transient processes is performed on the basis of data on postseismic processes accompanying the first Simushir earthquake on 15 November 2006 and Maule earthquake on 27 February 2010.The methodology of modelling a viscoelastic relaxation process after a large intraplate subduction earthquake is presented. A priori parameters of the selected model describing observed postseismic effects are adjusted by minimizing deviations between modeled surface displacements and actual surface displacements recorded by geodetic methods through solving corresponding inverse problems.The presented methodology yielded estimations of Maxwell’s viscosity of the asthenosphere of the central Kuril Arc and also of the central Chile. Besides, postseismic slip distribution patterns were obtained for the focus of the Simushir earthquake of 15 November 2006 (Mw=8.3 (Figure 3, and distribution patterns of seismic and postseismic slip were determined for the focus of the Maule earthquake of 27 February 2010 (Mw=8.8 (Figure 6. These estimations and patterns can provide for prediction of the intensity of viscoelastic stress attenuation in the asthenosphere; anomalous values should be taken into account as adjustment factors when analyzing inter-seismic deformation in order to ensure correct estimation of the accumulated elastic seismogenic potential.

  2. Driving forces: Slab subduction and mantle convection

    Science.gov (United States)

    Hager, Bradford H.

    1988-01-01

    Mantle convection is the mechanism ultimately responsible for most geological activity at Earth's surface. To zeroth order, the lithosphere is the cold outer thermal boundary layer of the convecting mantle. Subduction of cold dense lithosphere provides tha major source of negative buoyancy driving mantle convection and, hence, surface tectonics. There are, however, importnat differences between plate tectonics and the more familiar convecting systems observed in the laboratory. Most important, the temperature dependence of the effective viscosity of mantle rocks makes the thermal boundary layer mechanically strong, leading to nearly rigid plates. This strength stabilizes the cold boundary layer against small amplitude perturbations and allows it to store substantial gravitational potential energy. Paradoxically, through going faults at subduction zones make the lithosphere there locally weak, allowing rapid convergence, unlike what is observed in laboratory experiments using fluids with temperature dependent viscosities. This bimodal strength distribution of the lithosphere distinguishes plate tectonics from simple convection experiments. In addition, Earth has a buoyant, relatively weak layer (the crust) occupying the upper part of the thermal boundary layer. Phase changes lead to extra sources of heat and bouyancy. These phenomena lead to observed richness of behavior of the plate tectonic style of mantle convection.

  3. Slab detachment of subducted Indo-Australian plate beneath Sunda ...

    Indian Academy of Sciences (India)

    both the Middle-America and Peru–Chile trench at 10 Ma and 20 Ma time windows are unknown. (figure 6). Recently an alternative view has been put forward according to which (Schellart et al. 2010) global dataset of current subduction kine- matics indicates negligible-to-moderate correlation between subducting plate ...

  4. Subduction of the primordial crust into the deep mantle

    Directory of Open Access Journals (Sweden)

    Hiroki Ichikawa

    2017-03-01

    Full Text Available The primordial crust on the Earth formed from the crystallization of the surface magma ocean during the Hadean. However, geological surveys have found no evidence of rocks dating back to more than 4 Ga on the Earth's surface, suggesting the Hadean crust was lost due to some processes. We investigated the subduction of one of the possible candidates for the primordial crust, anorthosite and KREEP crust similar to the Moon, which is also considered to have formed from the crystallization of the magma ocean. Similar to the present Earth, the subduction of primordial crust by subduction erosion is expected to be an effective way of eliminating primordial crust from the surface. In this study, the subduction rate of the primordial crust via subduction channels is evaluated by numerical simulations. The subduction channels are located between the subducting slab and the mantle wedge and are comprised of primordial crust materials supplied mainly by subduction erosion. We have found that primordial anorthosite and KREEP crust of up to ∼50 km thick at the Earth's surface was able to be conveyed to the deep mantle within 0.1-2 Gy by that mechanism.

  5. Slab detachment of subducted Indo-Australian plate beneath Sunda ...

    Indian Academy of Sciences (India)

    ... complicate the subduction zone processes and slab architecture. Based on evidences which include patterns of seismicity, seismic tomography and geochemistry of arc volcanoes, we have identified a horizontal slab tear in the subducted Indo-Australian slab beneath the Sunda arc. It strongly reflects on trench migration, ...

  6. Viscous Dissipation and Criticality of Subducting Slabs

    Science.gov (United States)

    Riedel, Mike; Karato, Shun; Yuen, Dave

    2016-04-01

    Rheology of subducting lithosphere appears to be complicated. In the shallow part, deformation is largely accomodated by brittle failure, whereas at greater depth, at higher confining pressures, ductile creep is expected to control slab strength. The amount of viscous dissipation ΔQ during subduction at greater depth, as constrained by experimental rock mechanics, can be estimated on the basis of a simple bending moment equation [1,2] 2ɛ˙0(z) ∫ +h/2 2 M (z) = h ṡ -h/2 4μ(y,z)y dy , (1) for a complex multi-phase rheology in the mantle transition zone, including the effects of a metastable phase transition as well as the pressure, temperature, grain-size and stress dependency of the relevant creep mechanisms; μ is here the effective viscosity and ɛ˙0(z) is a (reference) strain rate. Numerical analysis shows that the maximum bending moment, Mcrit, that can be sustained by a slab is of the order of 1019 Nm per m according to Mcrit˜=σp ∗h2/4, where σp is the Peierl's stress limit of slab materials and h is the slab thickness. Near Mcrit, the amount of viscous dissipation grows strongly as a consequence of a lattice instability of mantle minerals (dislocation glide in olivine), suggesting that thermo-mechanical instabilities become prone to occur at places where a critical shear-heating rate is exceeded, see figure. This implies that the lithosphere behaves in such cases like a perfectly plastic solid [3]. Recently available detailed data related to deep seismicity [4,5] seems to provide support to our conclusion. It shows, e.g., that thermal shear instabilities, and not transformational faulting, is likely the dominating mechanism for deep-focus earthquakes at the bottom of the transition zone, in accordance with this suggested "deep criticality" model. These new findings are therefore briefly outlined and possible implications are discussed. References [1] Riedel, M. R., Karato, S., Yuen, D. A. Criticality of Subducting Slabs. University of Minnesota

  7. Optimal multi-dimensional poverty lines: The state of poverty in Iraq

    Science.gov (United States)

    Ameen, Jamal R. M.

    2017-09-01

    Poverty estimation based on calories intake is unrealistic. The established concept of multidimensional poverty has methodological weaknesses in the treatment of different dimensions and there is disagreement in methods of combining them into a single poverty line. This paper introduces a methodology to estimate optimal multidimensional poverty lines and uses the Iraqi household socio-economic survey data of 2012 to demonstrate the idea. The optimal poverty line for Iraq is found to be 170.5 Thousand Iraqi Dinars (TID).

  8. An optical coherence tomography (OCT)-based air jet indentation system for measuring the mechanical properties of soft tissues

    Science.gov (United States)

    Huang, Yan-Ping; Zheng, Yong-Ping; Wang, Shu-Zhe; Chen, Zhong-Ping; Huang, Qing-Hua; He, Yong-Hong

    2009-01-01

    A novel noncontact indentation system with the combination of an air jet and optical coherence tomography (OCT) was presented in this paper for the quantitative measurement of the mechanical properties of soft tissues. The key idea of this method is to use a pressure-controlled air jet as an indenter to compress the soft tissue in a noncontact way and utilize the OCT signals to extract the deformation induced. This indentation system provides measurement and mapping of tissue elasticity for small specimens with high scanning speed. Experiments were performed on 27 silicone tissue-mimicking phantoms with different Young's moduli, which were also measured by uniaxial compression tests. The regression coefficient of the indentation force to the indentation depth (N mm-1) was used as an indicator of the stiffness of tissue under air jet indentation. Results showed that the stiffness coefficients measured by the current system correlated well with the corresponding Young's moduli obtained by conventional mechanical testing (r = 0.89, p < 0.001). Preliminary in vivo tests also showed that the change of soft tissue stiffness with and without the contraction of the underlying muscles in the hand could be differentiated by the current measurement. This system may have broad applications in tissue assessment and characterization where alterations of mechanical properties are involved, in particular with the potential of noncontact micro-indentation for tissues.

  9. Understanding energy poverty - Case study: Tajikistan

    Energy Technology Data Exchange (ETDEWEB)

    Robic, Slavica; Olshanskaya, Marina; Vrbensky, Rastislav; Morvaj, Zoran

    2010-09-15

    Access and affordability to energy services determine the state of energy poverty; however, there is no widely applicable definition of energy poverty and no universal set of measures for its eradication exists. This paper offers a new definition and possible solution for decrease, and eventually eradication, of energy poverty for the specific case of Tajikistan. As eradication of energy poverty needs to go in hand with nature preservation and economic development, authors provide possible approach to decrease of energy poverty in Tajikistan while simultaneously preserving nature and boosting the local economy.

  10. Freedom and poverty in the fishery commons

    Directory of Open Access Journals (Sweden)

    Svein Jentoft

    2010-01-01

    Full Text Available Abstract In fisheries, alleviating poverty sometimes requires strategies that are inherently in conflict. When aiming to develop a fishery as a means to reduce poverty, its common pool resource basis might be undermined, resulting in greater poverty. But poverty in fisheries is also linked to, or a part of deeper social issues and processes, for instance, the marginalization and exclusion of certain communities. Poverty also has many factors— income, health, literacy, gender, power, security, etc.—all of which make poverty alleviation a particularly “wicked problem” that would require a broad process of political, social and institutional reform. In other words, poverty alleviation is not only an issue of sustainable resource management but also one of societal governance. Drawing from research in small-scale fisheries communities in Nicaragua, Tanzania, and Bangladesh, this paper describes how fishing people cope with poverty. The paper discusses what the governance implications are for alleviating poverty at individual, household and community levels, and argue that both the definition of poverty and poverty alleviation in small-scale fisheries must be rooted in real life experiences.

  11. Inequality, income, and poverty: comparative global evidence.

    Science.gov (United States)

    Fosu, Augustin Kwasi

    2010-01-01

    Objectives. The study seeks to provide comparative global evidence on the role of income inequality, relative to income growth, in poverty reduction.Methods. An analysis-of-covariance model is estimated using a large global sample of 1980–2004 unbalanced panel data, with the headcount measure of poverty as the dependent variable, and the Gini coefficient and PPP-adjusted mean income as explanatory variables. Both random-effects and fixed-effects methods are employed in the estimation.Results. The responsiveness of poverty to income is a decreasing function of inequality, and the inequality elasticity of poverty is actually larger than the income elasticity of poverty. Furthermore, there is a large variation across regions (and countries) in the relative effects of inequality on poverty.Conclusion. Income distribution plays a more important role than might be traditionally acknowledged in poverty reduction, though this importance varies widely across regions and countries.

  12. A Regional Look at Poverty in Turkey

    Directory of Open Access Journals (Sweden)

    Hasan Engin Duran

    2015-12-01

    Full Text Available AbstractPurpose of this study is to investigate the evolution, geographical distribution and convergence of poverty rates across Turkish  regions over 2006-2013. We use dataset  from TURKSTAT where the povertyrate is calculated using the median-income. Methodologically, Moran’s I tests, Conditional Kernel-Density and Markov Transition Probability Matrices are used. Our analyses indicate three results. First, at national-level, number of people living under poverty and poverty rate have declined. This decline was  observed in Western regions while increase was observed in less developed Eastern regions. Second , poverty rates follow geographically correlated pattern. Third, regional poverty rates do not tend to converge eachother.Keywords: Regional Poverty Rates, Relative Poverty, Spatial Moran’s I Test,Conditional Kernel Density Estimations,Markov Transition Probability MatricesJEL Classification Codes: I32, R12, R52, I30

  13. Beyond the feminisation of poverty: gender-aware poverty reduction.

    Science.gov (United States)

    Lockwood, M; Baden, S

    1995-09-01

    There must be an awareness of gender issues in poverty reduction programs. For example, program efforts that direct aid to the promotion of labor intensive employment options disregard women's already overburdened work regime. Public expenditures to benefit the poor, such as primary education or reformed agricultural extension, may be based on the assumption that men and women will benefit equally, yet there is often gender bias in the delivery of services. One recommendation is to target female headed households in budget-constrained anti-poverty programs. One of the few examples of such programs provides urban female household heads in Chile with employment training, housing, health care, child care, and legal aid services. Causes of female headship vary, and a simple correlation with poverty is not always the case. Well-intentioned women-in-development credit programs in Ghana and Bangladesh have been "hijacked" by men. Programs to address gender discrimination only among the poor may overlook other oppressed women. In India gender discrimination is often greatest among women in wealthy households. Programs must offer more than economic resources, they must help women stretch traditional gender boundaries and obtain skills such as literacy or financial management. They must help women organize collectively to protest injustices and achieve institutional reforms.

  14. An Instrumented Macro-Indentation Method for Determining the Mechanical Properties of Coconut Shell (Coco Nucifera of Cameroon)

    OpenAIRE

    Njeugna, E.; Ganou, M.B.K.; Ndapeu, D.; Foba, J.N.T.; Sikame , N.R.T.; Huisken , P.W.M.

    2016-01-01

    International audience; An instrumented macro-indentation test was used to determine the viscoelastic parameters and hardness of the shell of Coco Nucifera from Cameroon in order to promote their use in the manufacture of abrasives. Samples measuring 10 mm x 10 mm x 3 mm were cut out from the bottom of the fruit, close to the natural indentations (the eye) of an approximately round-shaped fruit. The indentation load ranged from 50 to 500 N with an increment of 50 N. A comparator with digital ...

  15. Poverty is Not Just an Indicator: The Relationship Between Income, Poverty, and Child Well-Being.

    Science.gov (United States)

    Chaudry, Ajay; Wimer, Christopher

    2016-04-01

    In this article, we review the evidence on the effects of poverty and low income on children's development and well-being. We argue that poverty is an important indicator of societal and child well-being, but that poverty is more than just an indicator. Poverty and low income are causally related to worse child development outcomes, particularly cognitive developmental and educational outcomes. Mechanisms through which poverty affects these outcomes include material hardship, family stress, parental and cognitive inputs, and the developmental context to which children are exposed. The timing, duration, and community context of poverty also appear to matter for children's outcomes-with early experiences of poverty, longer durations of poverty, and higher concentrations of poverty in the community leading to worse child outcomes. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  16. Characteristics of focal mechanisms in Chile subduction

    Directory of Open Access Journals (Sweden)

    Wang Xiaoshan

    2012-08-01

    Full Text Available We use the Centroid Moment Tensor (CMT solution of the earthquakes occurred in Chile subduction to analyze the characteristics of focal mechanisms. We define the angle between P, B, and T axes of focal mechanisms and three stress axes of tectonic stress field as the consistency parameter, to research the dynamic changes of focal mechanism pattern in earthquake preparation area before the 2010 Maule, Chile earthquake. The result shows that the consistency parameter decreases before the earthquake, and the area of the lower consistent parameter visually coincides with the distribution of aftershocks. This phenomenon is similar to the Load-Unload Response Ratio (LURR decreases prior to the occurrence of macro-fracture happened in the acoustic emission experiments involving large rock specimens under tri-axial stress.

  17. Global Poverty, Justice and Taxation

    Directory of Open Access Journals (Sweden)

    Ciprian Niţu

    2012-10-01

    Full Text Available The question of poverty and justice inside global economic system has received three major types of responses in political theory. The communitarian perspective considers political culture of a society as the main cause of the wealth of that society, and accordingly limits the redistributive duty to the nation-state borders. A second view, which can be called liberal internationalism, claims that trade liberalization is the best way to reduce poverty in developing countries and create a more equitable and stable economic order. This paper argues that a third perspective seems to be a better approach. The cosmopolitan perspective points out that international economic system should be reformed by building up a global tax regime.

  18. Governance, Growth and Poverty Reduction

    OpenAIRE

    Mushtaq H. Khan

    2009-01-01

    Poverty reduction is a function of economic growth, income distribution and distribution changes. Governance can impact both growth and income distribution. The dominant market-enhancing governance paradigm seeks to enhance the efficiency of markets through ‘good governance’ reforms, ostensibly to trigger or sustain growth. ‘Pro-poor’ good governance reforms purport to enhance the scale and efficiency of service delivery to the poor. The good governance approach to enhancing growth is dispute...

  19. Rice trade liberalization and poverty

    OpenAIRE

    Gulati, Ashok; Narayanan, Sudha

    2002-01-01

    Rice is the lifeline of almost 70% of the world's poor residing in Asia, where more than 90% of world rice production and consumption takes place. Rice trade liberalization therefore has tremendous implications for poverty. The world rice market is highly distorted, partly because of the high degree of intervention in rice markets across the world. While poor countries such as Thailand, Vietnam, and India tend to “disprotect” rice sectors, the rich countries of East Asia (Japan and Korea), Eu...

  20. Poverty, governance and economic growth

    Directory of Open Access Journals (Sweden)

    Kefi Mohamed Karim

    2013-07-01

    Full Text Available The objective of this paper is to study the effect of governance and povrety on economic growth of a set of eight developing countries during the period 2000-2009, using a dynamic and static panel data model and a simultaneous equations model. The key findings generated from these three empirical tests stipulate a negative effect of governance on povrety and a positive effect of political instability and corruption on poverty

  1. Climate Change and Poverty Nexus

    OpenAIRE

    O. Babalola Oladapo; A. Igbatayo Samuel

    2014-01-01

    Climate change and poverty are global issues which cannot be waved aside in welfare of the ever increasing population. The causes / consequences are far more elaborate in developing countries, including Nigeria, which poses threats to the existence of man and his environment. The dominant role of agriculture makes it obvious that even minor climate deteriorations can cause devastating socio-economic consequences. Policies to curb the climate change by reducing the consumption of fossil fuels ...

  2. Poverty Traps and Climate Change

    OpenAIRE

    Tol, Richard S. J.

    2011-01-01

    PUBLISHED We use a demo-economic model to examine the question of whether climate change could widen or deepen poverty traps. The model includes two crucial mechanisms. Parents are risk averse when deciding how many children to have; fertility is high when infant survival is low. High fertility spreads scarce household resources thin, resulting in children being poorly educated. At the macro level, technological progress is slow because of decreasing returns to scale in agriculture. With h...

  3. Depositionary Margins: The Destruction and Renovation of Subduction Forearcs

    Science.gov (United States)

    Vannucchi, P.; Morgan, J. P.; Silver, E. A.; Kluesner, J.

    2016-12-01

    A depositionary margin is a new framework for forearc evolution that focuses on the potential feedbacks between subduction tectonics, sedimentation, and geomorphology that take place during an extreme event of subduction erosion. These feedbacks can lead to the creation of a forearc structure that extends the traditional division of forearcs into accretionary or erosive subduction margins by demonstrating a mode of rapid basin accretion during an erosive event at a subduction margin. A depositionary mode of forearc evolution occurs when terrigenous sediments are deposited directly on the forearc while it is being removed from below by subduction erosion. In the most extreme case, an entire forearc can be removed by a single subduction erosion event followed by depositionary replacement without involving transfer of sediments from the incoming plate. We need to further recognize that subduction forearcs are often shaped by interactions between slow, long-term processes and sudden extreme events reflecting the sudden influences of large-scale morphological variations in the incoming plate. Both types of processes contribute to the large-scale architecture of the forearc, with extreme events associated with a replacive depositionary mode that rapidly creates sections of a typical forearc margin. The persistent upward diversion of the megathrust is likely to affect its geometry, frictional nature, and hydrogeology. Therefore, the stresses along the fault and individual earthquake rupture characteristics are also expected to be more variable in these erosive systems than in systems with long-lived megathrust surfaces.

  4. Measuring and monitoring energy poverty

    International Nuclear Information System (INIS)

    Pachauri, Shonali; Spreng, Daniel

    2011-01-01

    This article undertakes a review of alternative measures and indicators of energy poverty targeted to specific audiences and for particular purposes. At the national and international scales there have been some efforts for constructing measures of energy poverty. However, much more needs to be done to develop an internationally consistent measurement framework and to put in place data collection systems that will enable regular reporting. At the programme and project level, indicator systems by necessity need to be designed for specific purposes. Nevertheless, the article proposes that in many instances it is desirable to widen the scope of metrics used for designing and evaluating policies and programmes. In the past, monitoring and evaluation indicators have focused largely on outputs, service delivery or dissemination. Central to the recommendations laid out in the paper is the call for widening the focus of evaluation and necessity to design indicators that adequately assess the needs of beneficiaries and describe the living conditions of families and communities, who are targeted by such programmes and initiatives. - Highlights: ► Consistent measurement frameworks and regular data collection systems on energy poverty are needed. ► Metrics used for designing and evaluating energy access programmes should be widened. ► Indicators that adequately assess needs and describe living conditions of targeted beneficiaries are required.

  5. Subducted oceanic relief locks the shallow megathrust in central Ecuador

    Science.gov (United States)

    Collot, Jean-Yves; Sanclemente, Eddy; Nocquet, Jean-Mathieu; Leprêtre, Angélique; Ribodetti, Alessandra; Jarrin, Paul; Chlieh, Mohamed; Graindorge, David; Charvis, Philippe

    2017-05-01

    Whether subducted oceanic reliefs such as seamounts promote seismic rupture or aseismic slip remains controversial. Here we use swath bathymetry, prestack depth-migrated multichannel seismic reflection lines, and wide-angle seismic data collected across the central Ecuador subduction segment to reveal a broad 55 km × 50 km, 1.5-2.0 km high, low height-to-width ratio, multipeaked, sediment-bare, shallow subducted oceanic relief. Owing to La Plata Island and the coastline being located, respectively, 35 km and 50-60 km from the trench, GPS measurements allow us to demonstrate that the subducted oceanic relief spatially correlates to a shallow, 80 km × 55 km locked interplate asperity within a dominantly creeping subduction segment. The oceanic relief geometrical anomaly together with its highly jagged topography, the absence of a subduction channel, and a stiff erosive oceanic margin are found to be long-term geological characteristics associated with the shallow locking of the megathrust. Although the size and level of locking observed at the subducted relief scale could produce an Mw >7+ event, no large earthquakes are known to have happened for several centuries. On the contrary, frequent slow slip events have been recorded since 2010 within the locked patch, and regular seismic swarms have occurred in this area during the last 40 years. These transient processes, together with the rough subducted oceanic topography, suggest that interplate friction might actually be heterogeneous within the locked patch. Additionally, we find that the subducted relief undergoes internal shearing and produces a permanent flexural bulge of the margin, which uplifted La Plata Island.

  6. Development of 3d micro-nano hybrid patterns using anodized aluminum and micro-indentation

    International Nuclear Information System (INIS)

    Shin, Hong Gue; Kwon, Jong Tae; Seo, Young Ho; Kim, Byeong Hee

    2008-01-01

    We developed a simple and cost-effective method of fabricating 3D micro-nano hybrid patterns in which micro-indentation is applied on the anodized aluminum substrate. Nano-patterns were formed first on the aluminum substrate, and then micro-patterns were fabricated by deforming the nano-patterned aluminum substrate. Hemispherical nano-patterns with a 150 nm-diameter on an aluminum substrate were fabricated by anodizing and alumina removing process. Then, micro-pyramid patterns with a side-length of 50 μm were formed on the nano-patterns using micro-indentation. To verify 3D micro-nano hybrid patterns, we replicated 3D micro-nano hybrid patterns by a hot-embossing process. 3D micro-nano hybrid patterns may be used in nano-photonic devices and nano-biochips applications

  7. Experimental tests of the impact of selected parameters on the indentation rolling resistances

    Science.gov (United States)

    Woźniak, Dariusz; Gładysiewicz, Lech; Konieczna, Martyna

    2018-01-01

    Belt conveyors are main part of transporting systems in mines and in many other branches of industry. During conveyor belt works different types of resistances are generated. Indentation rolling resistance is the most significant component of the resistances from the perspective of energy losses and it cause the biggest costs as well. According to latest state of analyses and measurements it is well known that theoretical rolling resistance were underestimated in comparison with the measured in-situ one. In this paper new method for determination indentation rolling resistance is presented. The authors compared theoretically and experimentally established damping factors. The relation between these two values enabled to obtain more precise equation for damping function. This function is one of the most important component in calculation of the rolling resistance. In new theoretical model value of rolling resistance is nearly twice higher than this used so far.

  8. Constitutive modeling of porcine liver in indentation using 3D ultrasound imaging.

    Science.gov (United States)

    Jordan, P; Socrate, S; Zickler, T E; Howe, R D

    2009-04-01

    In this work we present an inverse finite-element modeling framework for constitutive modeling and parameter estimation of soft tissues using full-field volumetric deformation data obtained from 3D ultrasound. The finite-element model is coupled to full-field visual measurements by regularization springs attached at nodal locations. The free ends of the springs are displaced according to the locally estimated tissue motion, and the normalized potential energy stored in all springs serves as a measure of model-experiment agreement for material parameter optimization. We demonstrate good accuracy of estimated parameters and consistent convergence properties on synthetically generated data. We present constitutive model selection and parameter estimation for perfused porcine liver in indentation, and demonstrate that a quasilinear viscoelastic model with shear modulus relaxation offers good model-experiment agreement in terms of indenter displacement (0.19 mm RMS error) and tissue displacement field (0.97 mm RMS error).

  9. CONTACT STRESSES IN A TRANSVERSELY ISOTROPIC SOLID CYLINDER LATERALLY COMPRESSED BY AN INDENTER

    Directory of Open Access Journals (Sweden)

    Ahmet YAPICI

    2004-03-01

    Full Text Available In this study, an elastostatic contact problem for a laterally compressed transversely isotropic cylinder subjected to radial compression through a circumferential rigid indenter is considered. The extent of the contact region and the stress distribution are sought. It is assumed that the contact between the cylinder and the rigid indenter is frictionless and only compressive normal tractions can be transmitted through the interface. Due to the geometry of the configuration, Fourier transform techniques are chosen. The problem is reduced to a singular integral equation. It is reduced to linear algebraic equation system by using Gauss Chebyshev Integration Formulae and is solved by using Gauss Elimination method. E glass and barium titanate are used as a transversely isotropic materials. The stress analysis is performed for different contact area, punch radiuses and cylinder radiuses. The obtained results are shown in figures.

  10. Construction of stess-strain curves for brittle materials by indentation in a wide temperature range

    Directory of Open Access Journals (Sweden)

    Milman Yu.V.

    2007-01-01

    Full Text Available A test method procedure for constructing stress-strain curves by indentation of brittle and low plastic materials under temperature ranging from 20 to 900°C was developed recently by Yu. Milman, B. Galanov et al. According to this test method procedure stress-strain curves σ - Є for Si, Ge, SiC, TiB2 and WC/Co hard alloy were constructed in the above temperature region and mechanical parameters such as elastic point, σe, yield stress, σs, etc. were extracted by using the measurement results obtained by a set of trihedral pyramid indenters with different angles at the tip, γ1, ranging from 45 to 85°C.

  11. CKD and poverty: a growing global challenge.

    Science.gov (United States)

    Hossain, Mohammed P; Goyder, Elizabeth C; Rigby, Jan E; El Nahas, Meguid

    2009-01-01

    Approximately 1.2 billion individuals worldwide live in extreme poverty (poverty (Poverty is most prevalent in developing countries, but does not spare richer economies, where huge income discrepancies have been reported. Poverty is a major health care marker affecting a number of chronic, communicable, and noncommunicable diseases. Poverty and social deprivation are known to affect the predisposition, diagnosis, and management of chronic diseases; they directly impact on the prevalence of such conditions as obesity, diabetes, and hypertension. Also, growing evidence links poverty to chronic kidney disease (CKD). This may be caused by a direct impact of poverty on CKD or indirectly through the increased health care burden linked to poverty-associated diabetes and hypertension. Furthermore, data have shown that the poor and socially deprived have a greater prevalence of end-stage renal disease. Access to renal care, dialysis, and transplantation may also be affected by social deprivation. Overall, poverty and social deprivation are emerging as major risk markers for CKD in both developing and developed countries. Their impact on CKD warrants careful analysis because it may confound the interpretation of CKD risk factors within communities. This review therefore aims to look at the evidence linking poverty to CKD and its major risk factors, namely, diabetes and hypertension.

  12. Social Construction of Poverty in Ghana: A Structural Sociological Analysis

    OpenAIRE

    William Boateng

    2014-01-01

    Poverty is a social construct largely based on the culture of poverty paradigm where the poor are blamed for their plight. Poverty constructed this way diverts attention from the social forces responsible for it. In order to thoroughly understand poverty in Ghana, therefore, we need to engage in the sociological imagination to see if poverty is a personal problem or a public issue. This paper aims to disprove the culture of poverty paradigm, which defines poverty as a personal problem, and re...

  13. Poverty and inequality issues in Albania: trends and determinants

    OpenAIRE

    Myftaraj (Tomori) Elena

    2010-01-01

    Poverty and inequality are complex and widespread phenomena. Poverty is an indicator and the main factor of inequality, so reduction of poverty is one of the biggest challenges for economic and social consolidation of a country. There are different concepts of poverty, in this paper we are focused on the concept of absolute poverty. The main objective of this paper is to conduct an analysis on the trends of poverty and inequality indicators, as well as an analysis on the reduction of poverty ...

  14. Assessing strain mapping by electron backscatter diffraction and confocal Raman microscopy using wedge-indented Si

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, Lawrence H.; Vaudin, Mark D.; Stranick, Stephan J.; Stan, Gheorghe; Gerbig, Yvonne B.; Osborn, William; Cook, Robert F., E-mail: robert.cook@nist.gov

    2016-04-15

    The accuracy of electron backscatter diffraction (EBSD) and confocal Raman microscopy (CRM) for small-scale strain mapping are assessed using the multi-axial strain field surrounding a wedge indentation in Si as a test vehicle. The strain field is modeled using finite element analysis (FEA) that is adapted to the near-indentation surface profile measured by atomic force microscopy (AFM). The assessment consists of (1) direct experimental comparisons of strain and deformation and (2) comparisons in which the modeled strain field is used as an intermediate step. Direct experimental methods (1) consist of comparisons of surface elevation and gradient measured by AFM and EBSD and of Raman shifts measured and predicted by CRM and EBSD, respectively. Comparisons that utilize the combined FEA–AFM model (2) consist of predictions of distortion, strain, and rotation for comparison with EBSD measurements and predictions of Raman shift for comparison with CRM measurements. For both EBSD and CRM, convolution of measurements in depth-varying strain fields is considered. The interconnected comparisons suggest that EBSD was able to provide an accurate assessment of the wedge indentation deformation field to within the precision of the measurements, approximately 2×10{sup −4} in strain. CRM was similarly precise, but was limited in accuracy to several times this value. - Highlights: • We map strain by electron backscatter diffraction and confocal Raman microscopy. • The test vehicle is the multi-axial strain field of wedge-indented silicon. • Strain accuracy is assessed by direct experimental intercomparison. • Accuracy is also assessed by atomic force microscopy and finite element analyses. • Electron diffraction measurements are accurate; Raman measurements need refinement.

  15. Comparison of cyclic and impact-based reference point indentation measurements in human cadaveric tibia.

    Science.gov (United States)

    Karim, Lamya; Van Vliet, Miranda; Bouxsein, Mary L

    2018-01-01

    Although low bone mineral density (BMD) is strongly associated with increased fracture risk, up to 50% of those who suffer fractures are not detected as high-risk patients by BMD testing. Thus, new approaches may improve identification of those at increased risk for fracture by in vivo assessment of altered bone tissue properties, which may contribute to skeletal fragility. Recently developed reference point indentation (RPI) allows for assessment of cortical bone indentation properties in vivo using devices that apply cyclic loading or impact loading, but there is little information available to assist with interpretation of RPI measurements. Our goals were to use human cadaveric tibia to determine: 1) the associations between RPI variables, cortical bone density, and morphology; 2) the association between variables obtained from RPI systems using cyclic, slow loading versus a single impact load; and 3) age-related differences in RPI variables. We obtained 20 human tibia and femur pairs from female donors (53-97years), measured total hip BMD using dual-energy X-ray absorptiometry, assessed tibial cortical microarchitecture using high-resolution peripheral quantitative computed tomography (HR-pQCT), and assessed cortical bone indentation properties at the mid-tibial diaphysis using both the cyclic and impact-based RPI systems (Biodent and Osteoprobe, respectively, Active Life Scientific, Santa Barbara, CA). We found a few weak associations between RPI variables, BMD, and cortical geometry; a few weak associations between measurements obtained by the two RPI systems; and no age-related differences in RPI variables. Our findings indicate that in cadaveric tibia from older women RPI measurements are largely independent of age, femoral BMD, and cortical geometry. Furthermore, measurements from the cyclic and impact loading RPI devices are weakly related to each other, indicating that each device reflects different aspects of cortical bone indentation properties

  16. Mechanical properties of orthodontic wires derived by instrumented indentation testing (IIT) according to ISO 14577.

    Science.gov (United States)

    Zinelis, Spiros; Al Jabbari, Youssef S; Gaintantzopoulou, Marianna; Eliades, George; Eliades, Theodore

    2015-01-01

    The aim of this study was the characterization of mechanical properties of representative types of orthodontic wires employing instrumented indentation testing (IIT) according to ISO 14577. Segments were cut from ten wires. The first six are made of stainless steel (SS), two are made of Ni-Ti, and the last two are made of titanium molybdenum alloys (TMA). Then, the Martens hardness (HM), the Vickers hardness (HVIT) based on indentation hardness (H IT), the indentation modulus (E IT), the ratio of elastic to total work (η IT), and the traditional Vickers hardness (HV1) were measured by IIT. The results were statistically analyzed by one-way ANOVA followed by Student-Newman-Keuls (SNK) test at a = 0.05. The HVIT and HV1 data were analyzed by paired t test (a = 0.05). SS wires showed the highest hardness followed by TMA and Ni-Ti alloys. However, all wires showed significantly lower HVIT compared to corresponding HV1, a finding probably appended to elastic recovery around the indentation. E IT for all wires tested was determined much lower than the nominal values of the corresponding alloys due to the implication of residual stress field at the slope of unloading curve. Elastic to total work ratio was ranged from 45.8 to 64.4 % which is higher than that expected for ductile alloys (<30 %). The products tested illustrated significant differences in their mechanical properties. Although IIT provides reliable data for hardness and elastic index of materials tested, the intense residual stress field developed during the manufacturing process significantly affects the determination of modulus of elasticity.

  17. Dynamic mechanical response of brain tissue in indentation in vivo, in situ and in vitro.

    Science.gov (United States)

    Prevost, Thibault P; Jin, Guang; de Moya, Marc A; Alam, Hasan B; Suresh, Subra; Socrate, Simona

    2011-12-01

    Characterizing the dynamic mechanical properties of brain tissue is deemed important for developing a comprehensive knowledge of the mechanisms underlying brain injury. The results gathered to date on the tissue properties have been mostly obtained in vitro. Learning how these results might differ quantitatively from those encountered in vivo is a critical step towards the development of biofidelic brain models. The present study provides novel and unique experimental results on, and insights into, brain biorheology in vivo, in situ and in vitro, at large deformations, in the quasi-static and dynamic regimes. The nonlinear dynamic response of the cerebral cortex was measured in indentation on the exposed frontal and parietal lobes of anesthetized porcine subjects. Load-unload cycles were applied to the tissue surface at sinusoidal frequencies of 10, 1, 0.1 and 0.01 Hz. Ramp-relaxation tests were also conducted to assess the tissue viscoelastic behavior at longer times. After euthanasia, the indentation test sequences were repeated in situ on the exposed cortex maintained in its native configuration within the cranium. Mixed gray and white matter samples were subsequently excised from the superior cortex to be subjected to identical indentation test segments in vitro within 6-7 h post mortem. The main response features (e.g. nonlinearities, rate dependencies, hysteresis and conditioning) were measured and contrasted in vivo, in situ and in vitro. The indentation response was found to be significantly stiffer in situ than in vivo. The consistent, quantitative set of mechanical measurements thereby collected provides a preliminary experimental database, which may be used to support the development of constitutive models for the study of mechanically mediated pathways leading to traumatic brain injury. Copyright © 2011 Acta Materialia Inc. All rights reserved.

  18. Macro-scale approach for rough frictionless multi-indentation on a viscoelastic half-space

    OpenAIRE

    DUBOIS, Guillaume; CESBRON, Julien; YIN, Hai Ping; ANFOSSO LEDEE, Fabienne

    2011-01-01

    This paper deals with the numerical study of frictionless viscoelastic tyre/road contact. The present macro-scale approach takes into account both the viscoelastic behaviour of the tyre and the roughness of the road surface by solving the contact problem between a rough multi-indentation surface and a viscoelastic half-space. The method relies on the fact that a viscoelastic solution can be instantaneously reduced to an elastic solution. A simplified description of viscoelastic material behav...

  19. Microindentation deformation of lithium dihydrogen phosphate single crystals: Microhardness measurement and indentation size effect

    Energy Technology Data Exchange (ETDEWEB)

    Iurchenko, Anton [Institute for Single Crystals, National Academy of Sciences of Ukraine, Lenin Avenue 60, 61001 Kharkiv (Ukraine); Borc, Jarosław, E-mail: j.borc@pollub.pl [Department of Applied Physics, Lublin University of Technology, ul. Nadbystrzycka 38, 20-618 Lublin (Poland); Sangwal, Keshra [Department of Applied Physics, Lublin University of Technology, ul. Nadbystrzycka 38, 20-618 Lublin (Poland); Voronov, Alexei [Institute for Single Crystals, National Academy of Sciences of Ukraine, Lenin Avenue 60, 61001 Kharkiv (Ukraine)

    2016-02-15

    The Vickers microhardness H{sub V} of the (110) and (111) as-grown faces of lithium dihydrogen phosphate (LDP) crystals was investigated as a function of applied load P. The microhardness H{sub V} of the two faces increases with load P i.e. reverse indentation size effect (reverse ISE) and the hardness of the (110) face is somewhat lower than that of the (111) face but this difference is not easily recognized for these planes due to large scatter in the data. The origin of observed ISE was analyzed using different approaches. It was found that: (1) Hays–Kendall's and Begley–Hutchinson's relations do not explain the origin of reverse ISE but Meyer's law describes the reverse ISE satisfactorily and its constants provide a link between ISE and formation of radial cracks with applied indentation load P, (2) reverse ISE is associated with tensile surface stresses, (3) despite its failure to explain reverse ISE, Begley–Hutchinson's relation is reliable to obtain load-independent hardness H{sub 0}, is 2337 MPa for LDP, and (4) the value of fracture toughness K{sub C} of LDP crystals lies between 4.7 and 12 MPa m{sup 1/2}. The load-independent hardness H{sub 0} of LDP is higher by a factor of 1.5 than that reported for undoped KDP and ADP crystals whereas its fracture toughness K{sub C} is higher by factor of about 20 than that of undoped KDP crystals. - Highlights: • Vickers indentations on the (110) and (111) faces of LDP crystals were made. • The microhardness H{sub V} was investigated as a function of applied load P. • Reverse indentation size effect was observed. • Fracture toughness K{sub C} from the radial cracks was calculated.

  20. Method of determining elastic and plastic mechanical properties of ceramic materials using spherical indenters

    Science.gov (United States)

    Adler, Thomas A.

    1996-01-01

    The invention pertains a method of determining elastic and plastic mechanical properties of ceramics, intermetallics, metals, plastics and other hard, brittle materials which fracture prior to plastically deforming when loads are applied. Elastic and plastic mechanical properties of ceramic materials are determined using spherical indenters. The method is most useful for measuring and calculating the plastic and elastic deformation of hard, brittle materials with low values of elastic modulus to hardness.

  1. Nuclear Weapon Yield Determination through Nano Indentation of Thermally Degraded Automobile Paint

    Science.gov (United States)

    2011-03-01

    detonation from a test device used in Operation Teapot (dashed lines) (Plum, 1958) ...............13 8. Agilent Nano Indenter G200...2 . (Bauer, 2010) also measured the spectral output of the AXTS and compared it to that measured in Operation Teapot . As shown in Figure 7, the...800, 1200, and 1800 W (solid lines) over the spectral output at 4 different times after detonation of a test device used in Operation Teapot (dashed

  2. Effect of ion irradiation and indentation depth on the kinetics of deformation during micro-indentation of Zr-2.5%Nb pressure tube material at 25 deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Bose, B. [Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario, N6A 5B9 (Canada); Klassen, R.J., E-mail: rklassen@eng.uwo.c [Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario, N6A 5B9 (Canada)

    2010-04-01

    Micro-indentation creep tests were performed at 25 deg. C on radial-normal samples cut from Zr-2.5Nb CANDU pressure tube material in both the as-fabricated condition and after irradiation with 8.5 MeV Zr{sup +} ions. The average indentation stress, and hence the yield stress, was found to increase with decreasing indentation depth and with increasing levels of ion irradiation. The activation energy of the indentation creep rate and hence the, activation energy of the obstacles that limit the rate of dislocation glide, was independent of indentation depth but increased from DELTAG{sub 0} = 0.185 to 0.215 mub{sup 3} with increasing ion irradiation damage. The magnitude of the activation energy indicates that ion irradiation introduces a new type of obstacle into the microstructure which reduces the low temperature indentation creep rate of Zr-2.5Nb pressure tubes. This is supported by TEM images showing that Zr{sup +} ion irradiation produces small, nanometer size, dislocation loops which act as obstacles to dislocation glide and thus influence both the yield stress and the activation energy of the low-temperature thermal creep of Zr-2.5Nb pressure tube material. These findings suggest that neutron irradiation will have similar effect upon yield stress and low-temperature thermal creep as the Zr{sup +} ion irradiation since both create similar crystallographic defects in Zr-2.5Nb pressure tubes.

  3. Young child poverty in the United States: Analyzing trends in poverty and the role of anti-poverty programs using the Supplemental Poverty Measure

    Science.gov (United States)

    Pac, Jessica; Nam, JaeHyun; Waldfogel, Jane; Wimer, Christopher

    2017-01-01

    Between 1968 and 2013, the poverty rate of young children age 0 to 5 years fell by nearly one third, in large part because of the role played by anti-poverty programs. However, young children in the U.S. still face a much higher rate of poverty than do older children in the U.S. They also continue to have a much higher poverty rate than do young children in other developed countries around the world. In this paper, we provide a detailed analysis of trends in poverty and the role of anti-poverty programs in addressing poverty among young children, using an improved measure of poverty, the Supplemental Poverty Measure. We examine changes over time and the current status, both for young children overall and for key subgroups (by child age, and by child race/ethnicity). Our findings can be summarized in three key points. First, poverty among all young children age 0–5 years has fallen since the beginning of our time series; but absent the safety net, today’s poverty rate among young children would be identical to or higher than it was in 1968. Second, the safety net plays an increasing role in reducing the poverty of young children, especially among Black non-Hispanic children, whose poverty rate would otherwise be 20.8 percentage points higher in 2013. Third, the composition of support has changed from virtually all cash transfers in 1968, to about one third each of cash, credit and in-kind transfers today. PMID:28659652

  4. Atomic force microscopy indentation of fluorocarbon thin films fabricated by plasma enhanced chemical deposition at low radio frequency power

    International Nuclear Information System (INIS)

    Sirghi, L.; Ruiz, A.; Colpo, P.; Rossi, F.

    2009-01-01

    Atomic force microscopy (AFM) indentation technique is used for characterization of mechanical properties of fluorocarbon (CF x ) thin films obtained from C 4 F 8 gas by plasma enhanced chemical vapour deposition at low r.f. power (5-30 W) and d.c. bias potential (10-80 V). This particular deposition method renders films with good hydrophobic property and high plastic compliance. Commercially available AFM probes with stiff cantilevers (10-20 N/m) and silicon sharpened tips (tip radius < 10 nm) are used for indentations and imaging of the resulted indentation imprints. Force depth curves and imprint characteristics are used for determination of film hardness, elasticity modulus and plasticity index. The measurements show that the decrease of the discharge power results in deposition of films with decreased hardness and stiffness and increased plasticity index. Nanolithography based on AFM indentation is demonstrated on thin films (thickness of 40 nm) with good plastic compliance.

  5. A phenomenological method of mechanical properties definition of reactor pressure vessels (RPV) steels VVER according to the ball indentation diagram

    International Nuclear Information System (INIS)

    Bakirov, M. B.; Potapov, V.V.; Massoud, J.P.

    2002-01-01

    This work presents specimen-free methods of a standard uniaxial tension diagram construction and RPV (reactor pressure vessel) steels VVER strength properties definition out of a continuous ball indentation diagram. A similarity phenomenon of uniaxial tension strain curves at a hardening area and an area of a ball indentation constitutes the ground of the methods. The methods are developed on the basis of the uniform graphic representation of elasto-plastic strain processes by indentation and tension and with the reception of the unified yield curve at a hardening area. The calculation results on the phenomenological method conducted for a wide range of RPV steels conditions of nuclear reactors have shown a good precision as far as strain curves construction by the uniaxial tension out of the elasto-plastic indentation diagram is concerned. (authors)

  6. Quantitative Imaging of the Stress/Strain Fields and Generation of Macroscopic Cracks from Indents in Silicon

    Directory of Open Access Journals (Sweden)

    Brian K. Tanner

    2017-11-01

    Full Text Available The crack geometry and associated strain field around Berkovich and Vickers indents on silicon have been studied by X-ray diffraction imaging and micro-Raman spectroscopy scanning. The techniques are complementary; the Raman data come from within a few micrometres of the indentation, whereas the X-ray image probes the strain field at a distance of typically tens of micrometres. For example, Raman data provide an explanation for the central contrast feature in the X-ray images of an indent. Strain relaxation from breakout and high temperature annealing are examined and it is demonstrated that millimetre length cracks, similar to those produced by mechanical damage from misaligned handling tools, can be generated in a controlled fashion by indentation within 75 micrometres of the bevel edge of 200 mm diameter wafers.

  7. Crack formation mechanisms during micro and macro indentation of diamond-like carbon coatings on elastic-plastic substrates

    DEFF Research Database (Denmark)

    Thomsen, N.B.; Fischer-Cripps, A.C.; Swain, M.V.

    1998-01-01

    of cracking and the fracture mechanisms taking place. In the study various diamond-like carbon (DLC) coatings deposited onto stainless steel and tool steel were investigated. Results primarily for one DLC system will be presented here. (C) 1998 Published by Elsevier Science S.A. All rights reserved.......In the present study crack formation is investigated on both micro and macro scale using spherical indenter tips. in particular, systems consisting of elastic coatings that are well adhered to elastic-plastic substrates are studied. Depth sensing indentation is used on the micro scale and Rockwell...... indentation on the macro scale. The predominant driving force for coating failure and crack formation during indentation is plastic deformation of the underlying substrate. The aim is to relate the mechanisms creating both delamination and cohesive cracking on both scales with fracture mechanical models...

  8. Microhardness with depth sensing indentation. Instruments methods and applications; Mesure de durete submicronique instrumentee. Methode et applications

    Energy Technology Data Exchange (ETDEWEB)

    Poissonnet, S

    1999-07-01

    The study of applied surface layer or modified layers lead to the development of depth sensing indentation instruments in which measurements of penetration depth replaces optical measurements of surface impressions and sub-micron hardness may be determined. Indentation curves, depth-load, of elastoplastic materials give informations about plasticity and elasticity. After a description of the micro-indentation techniques we show few applications. Irradiation effects are measured in different materials like hafnium diboride, stainless steel or kapton. Hardness in oxide formed on metal study give informations. All these examples show that the nano-indentation is a powerful mean in the physical studies of materials because of a good statistic may be obtained and we have access to thin samples and to small phases. (author)

  9. Influence of lateral slab edge distance on plate velocity, trench velocity, and subduction partitioning

    NARCIS (Netherlands)

    Schellart, W. P.; Stegman, D. R.; Farrington, R. J.; Moresi, L.

    2011-01-01

    Subduction of oceanic lithosphere occurs through both trenchward subducting plate motion and trench retreat. We investigate how subducting plate velocity, trench velocity and the partitioning of these two velocity components vary for individual subduction zone segments as a function of proximity to

  10. Fracture Characteristics of Dlc on Silicon Using Nano-Indentation and Fea

    Science.gov (United States)

    Baek, Seung; Seok, Chang-Sung

    In this study, using the nano and micro-indentation tests and finite element analysis (FEA), we investigated the fracture behaviors of diamond like carbon (DLC) on silicon in indentation state. Diamond like carbon coating of 3μm and 1.5μm thickness were deposited on polished (100) single crystal silicon substrates by radio frequency plasma assisted chemical vapor deposition (RF-PACVD), respectively. Fracture toughness of DLC films was calculated from the measured lengths of the cracks formed by nano and micro-indentation on each sample. We used various equations such as Lawn's and Liang's equation to calculate the fracture toughness. The effective fracture toughnesses of these DLC films were 1.2 ~1.3 MPam0.5, calculated by Lawn's and Liang's equations. The true fracture toughness of DLC on silicon, excluding the portion of fracture toughness due to a substrate, was determined to be 4.0~5.1MPam0.5. DLC films with crack initiation and propagation were analyzed by finite element method.

  11. A novel numerical framework for self-similarity in plasticity: Wedge indentation in single crystals

    Science.gov (United States)

    Juul, K. J.; Niordson, C. F.; Nielsen, K. L.; Kysar, J. W.

    2018-03-01

    A novel numerical framework for analyzing self-similar problems in plasticity is developed and demonstrated. Self-similar problems of this kind include processes such as stationary cracks, void growth, indentation etc. The proposed technique offers a simple and efficient method for handling this class of complex problems by avoiding issues related to traditional Lagrangian procedures. Moreover, the proposed technique allows for focusing the mesh in the region of interest. In the present paper, the technique is exploited to analyze the well-known wedge indentation problem of an elastic-viscoplastic single crystal. However, the framework may be readily adapted to any constitutive law of interest. The main focus herein is the development of the self-similar framework, while the indentation study serves primarily as verification of the technique by comparing to existing numerical and analytical studies. In this study, the three most common metal crystal structures will be investigated, namely the face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close packed (HCP) crystal structures, where the stress and slip rate fields around the moving contact point singularity are presented.

  12. Ultrawide band gaps in beams with double-leaf acoustic black hole indentations.

    Science.gov (United States)

    Tang, Liling; Cheng, Li

    2017-11-01

    Band gaps in conventional phononic crystals (PCs) are attractive for applications such as vibration control, wave manipulation, and sound absorption. Their practical implementations, however, are hampered by several factors, among which the large number of cells required and their impractically large size to ensure the stopbands at reasonably low frequencies are on the top of the list. This paper reports a type of beam carved inside with two double-leaf acoustic black hole indentations. By incorporating the local resonance effect and the Bragg scattering effect generated by a strengthening stud connecting the two branches of the indentations, ultrawide band gaps are achieved. Increasing the length of the stud or reducing the residual thickness of the indentation allows the tuning of the band gaps to significantly enlarge the band gaps, which can exceed 90% of the entire frequency range of interest. Experimental results show that with only three cells, the proposed beam allows considerable vibration energy attenuation within an ultra-broad frequency range including the low frequency range, which conventional PCs can hardly reach. Meanwhile, the proposed configuration also enhances the structural integrity, thus pointing at promising applications in vibration control and a high performance wave filter design.

  13. Assessment of surface caking of powders using the ball indentation method.

    Science.gov (United States)

    Chen, Qinqin; Zafar, Umair; Ghadiri, Mojtaba; Bi, Jinfeng

    2017-04-15

    Powder caking is a ubiquitous problem, which could significantly decrease product quality and lead to economic losses. Hence it is important to know the conditions under which it occurs. The caking behaviour of three powder materials (PVP, HPC and CaHPO 4 ) has been investigated by the ball indentation method (BIM) as affected by relative humidity (RH), temperature and time. The resistance to powder flow, as indicated by the hardness is measured by a ball indenting the powder bed surface. The surface hardness increases with increasing RH and temperature, indicating caking of the powder bed. Moreover, the temperature and RH show a coupled effect on powder caking. Irreversible caking is formed in PVP and HPC at 75% RH; the particles coalesce and the volume of powder bed is significantly reduced with time. However, the caking of CaHPO 4 is reversible. To examine the caking mechanism of PVP and HPC, the critical glass transition RH is determined at 25°C and 45°C. The values are 63% and 53% RH for PVP and 61% and 50% RH for HPC, respectively. The glass transition moisture content in the ball indentation experiments is comparable with that determined by the dynamic vapor sorption measurement. BIM could be a fast and effective method for the assessment of powder surface caking. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. TEM in situ cube-corner indentation analysis using ViBe motion detection algorithm

    Science.gov (United States)

    Yano, K. H.; Thomas, S.; Swenson, M. J.; Lu, Y.; Wharry, J. P.

    2018-04-01

    Transmission electron microscopic (TEM) in situ mechanical testing is a promising method for understanding plasticity in shallow ion irradiated layers and other volume-limited materials. One of the simplest TEM in situ experiments is cube-corner indentation of a lamella, but the subsequent analysis and interpretation of the experiment is challenging, especially in engineering materials with complex microstructures. In this work, we: (a) develop MicroViBE, a motion detection and background subtraction-based post-processing approach, and (b) demonstrate the ability of MicroViBe, in combination with post-mortem TEM imaging, to carry out an unbiased qualitative interpretation of TEM indentation videos. We focus this work around a Fe-9%Cr oxide dispersion strengthened (ODS) alloy, irradiated with Fe2+ ions to 3 dpa at 500 °C. MicroViBe identifies changes in Laue contrast that are induced by the indentation; these changes accumulate throughout the mechanical loading to generate a "heatmap" of features in the original TEM video that change the most during the loading. Dislocation loops with b = ½ identified by post-mortem scanning TEM (STEM) imaging correspond to hotspots on the heatmap, whereas positions of dislocation loops with b = do not correspond to hotspots. Further, MicroViBe enables consistent, objective quantitative approximation of the b = ½ dislocation loop number density.

  15. Characterization of Adhesion in Pressure Sensitive Adhesives with a Spherical Indenter

    Science.gov (United States)

    Crosby, Alfred; Shull, Kenneth R.

    1997-03-01

    A combination of interfacial effects and bulk viscoelastic behavior controls the performance of pressure sensitive adhesives. We have studied these issues using commercially available adhesive transfer tapes. Using a spherical indenter, these experiments measure the displacement of the indenter into the adhesive as a function of the applied normal contact force. With the assumption of linear elastic behavior under small displacements, accepted theories of this contact problem are used to approximate the contact area and calculate a plateau modulus from the loading data. Fracture mechanics approaches based on linear elasticity also allow us to calculate the energy release rate (i.e. driving force for adhesive failure) from the load/displacement relationship measured during unloading. To alleviate uncertainty in the calculation of the plateau modulus and energy release rate for thicknesses not within the ranges of accepted theories, a finite element model simulates the behavior of the polymer layer upon loading and pull-off of the indenter. Future work will include modeling the adhesive with a viscoelastic constitutive model and characterizing the effects of geometry, substrate material, and loading rate on the adhesive properties.

  16. Fragmentation of copper current collectors in Li-ion batteries during spherical indentation

    International Nuclear Information System (INIS)

    Wang, Hsin; Watkins, Thomas R.; Simunovic, Srdjan; Bingham, Philip R.; Allu, Srikanth; Turner, John A.

    2017-01-01

    Large, areal, brittle fracture of copper current collector foils was observed by 3D x-ray computed tomography (XCT) of a spherically indented Li-ion cell. This fracture was hidden and non-catastrophic to a degree because the graphite layers deformed plastically, and held the materials together so that the cracks in the foils could not be seen under optical and electron microscopy. 3D XCT on the indented cell showed “mud cracks” within the copper layer. The cracking of copper foils could not be immediately confirmed when the cell was opened for post-mortem examination. However, an X-ray radiograph on a single foil of the Cu anode showed clearly that the copper foil had broken into multiple pieces similar to the brittle cracking of a ceramic under indentation. This new failure mode of anodes on Li-ion cell has very important implications on the behavior of Li-ion cells under mechanical abuse conditions. Furthermore, the fragmentation of current collectors in the anode must be taken into consideration for the electrochemical responses which may lead to capacity loss and affect thermal runaway behavior of the cells.

  17. Giant panda׳s tooth enamel: Structure, mechanical behavior and toughening mechanisms under indentation.

    Science.gov (United States)

    Weng, Z Y; Liu, Z Q; Ritchie, R O; Jiao, D; Li, D S; Wu, H L; Deng, L H; Zhang, Z F

    2016-12-01

    The giant panda׳s teeth possess remarkable load-bearing capacity and damage resistance for masticating bamboos. In this study, the hierarchical structure and mechanical behavior of the giant panda׳s tooth enamel were investigated under indentation. The effects of loading orientation and location on mechanical properties of the enamel were clarified and the evolution of damage in the enamel under increasing load evaluated. The nature of the damage, both at and beneath the indentation surfaces, and the underlying toughening mechanisms were explored. Indentation cracks invariably were seen to propagate along the internal interfaces, specifically the sheaths between enamel rods, and multiple extrinsic toughening mechanisms, e.g., crack deflection/twisting and uncracked-ligament bridging, were active to shield the tips of cracks from the applied stress. The giant panda׳s tooth enamel is analogous to human enamel in its mechanical properties, yet it has superior hardness and Young׳s modulus but inferior toughness as compared to the bamboo that pandas primarily feed on, highlighting the critical roles of the integration of underlying tissues in the entire tooth and the highly hydrated state of bamboo foods. Our objective is that this study can aid the understanding of the structure-mechanical property relations in the tooth enamel of mammals and further provide some insight on the food habits of the giant pandas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Mechanical indentation improves cerebral blood oxygenation signal quality of functional near-infrared spectroscopy (fNIRS) during breath holding

    Science.gov (United States)

    Vogt, William C.; Romero, Edwin; LaConte, Stephen M.; Rylander, Christopher G.

    2013-03-01

    Functional near-infrared spectroscopy (fNIRS) is a well-known technique for non-invasively measuring cerebral blood oxygenation, and many studies have demonstrated that fNIRS signals can be related to cognitive function. However, the fNIRS signal is attenuated by the skin, while scalp blood content has been reported to influence cerebral oxygenation measurements. Mechanical indentation has been shown to increase light transmission through soft tissues by causing interstitial water and blood flow away from the compressed region. To study the effects of indentation on fNIRS, a commercial fNIRS system with 16 emitter/detector pairs was used to measure cerebral blood oxygenation at 2 Hz. This device used diffuse reflectance at 730 nm and 850 nm to calculate deoxy- and oxy-hemoglobin concentrations. A borosilicate glass hemisphere was epoxied over each sensor to function as both an indenter and a lens. After placing the indenter/sensor assembly on the forehead, a pair of plastic bands was placed on top of the fNIRS headband and strapped to the head to provide uniform pressure and tightened to approx. 15 N per strap. Cerebral blood oxygenation was recorded during a breath holding regime (15 second hold, 15 second rest, 6 cycles) in 4 human subjects both with and without the indenter array. Results showed that indentation increased raw signal intensity by 85 +/- 35%, and that indentation increased amplitude of hemoglobin changes during breath cycles by 313% +/- 105%. These results suggest that indentation improves sensing of cerebral blood oxygenation, and may potentially enable sensing of deeper brain tissues.

  19. Determination of local constitutive properties of titanium alloy matrix in boron-modified titanium alloys using spherical indentation

    International Nuclear Information System (INIS)

    Sreeranganathan, A.; Gokhale, A.; Tamirisakandala, S.

    2008-01-01

    The constitutive properties of the titanium alloy matrix in boron-modified titanium alloys are different from those of the corresponding unreinforced alloy due to the microstructural changes resulting from the addition of boron. Experimental and finite-element analyses of spherical indentation with a large penetration depth to indenter radius ratio are used to compute the local constitutive properties of the matrix alloy. The results are compared with that of the corresponding alloy without boron, processed in the same manner

  20. Study of the Tool Geometry Influence in Indentation for the Analysis and Validation of the New Modular Upper Bound Technique

    Directory of Open Access Journals (Sweden)

    Carolina Bermudo

    2016-07-01

    Full Text Available Focusing on incremental bulk metal forming processes, the indentation process is gaining interest as a fundamental part of these kinds of processes. This paper presents the analysis of the pressure obtained in indentation under the influence of different punch geometries. To this end, an innovative Upper Bound Theorem (UBT based solution is introduced. This new solution can be easily applied to estimate the necessary force that guarantees plastic deformation by an indentation process. In this work, we propose an accurate analytical approach to analyse indentation under different punches. The new Modular Upper Bound (MUB method presents a simpler and faster application. Additionally, its complexity is not considerably increased by the addition of more Triangular Rigid Zones. In addition, a two-dimensional indentation model is designed and implemented using the Finite Element Method (FEM. The comparison of the two methods applied to the indentation process analysed—the new Modular Upper Bound technique and the Finite Element Method—reveal close similarities, the new Modular Upper Bound being more computationally efficient.

  1. Characterization of Rockwell hardness indenter Tip using image processing and optical profiler and evaluation of measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Moona G.

    2014-01-01

    Full Text Available Hardness is a measure of the resistance of a material to be penetrated and eroded by sharp projections of other materials such as diamond. The process of creating sharp projections on any test surface is known as indentation. Hardness measurement of any material is the result of a complex process of deformation during indentation. The indenter tip geometry, which includes radius of curvature at the tip and tip angle, affects the hardness measurement by influencing the nature of the penetration process on the test surface, because every indenter deforms the specimen surface with a different geometry. The controlled indenter geometry can improve the consistency of hardness measurement. In this paper we report the estimation of two important geometrical parameters, radius of curvature and tip angle of a Rockwell indenter by using a simple method of image processing and compare the results with those obtained with a traceable 3D optical profiler. Evaluation of uncertainty in measuremts is carried out as per ISO guidelines (ISO-GUM and a detailed uncertainty budget is presented. The tip angle estimted is 119.95 degree. The radius of curvature is estimted to be 199.96 ± 0.80μm by image analysis which agrees well with the value estimated by using optical profiler i.e. 199.12 μm.

  2. Hardening Effect Analysis by Modular Upper Bound and Finite Element Methods in Indentation of Aluminum, Steel, Titanium and Superalloys

    Science.gov (United States)

    Bermudo, Carolina; Sevilla, Lorenzo; Martín, Francisco; Trujillo, Francisco Javier

    2017-01-01

    The application of incremental processes in the manufacturing industry is having a great development in recent years. The first stage of an Incremental Forming Process can be defined as an indentation. Because of this, the indentation process is starting to be widely studied, not only as a hardening test but also as a forming process. Thus, in this work, an analysis of the indentation process under the new Modular Upper Bound perspective has been performed. The modular implementation has several advantages, including the possibility of the introduction of different parameters to extend the study, such as the friction effect, the temperature or the hardening effect studied in this paper. The main objective of the present work is to analyze the three hardening models developed depending on the material characteristics. In order to support the validation of the hardening models, finite element analyses of diverse materials under an indentation are carried out. Results obtained from the Modular Upper Bound are in concordance with the results obtained from the numerical analyses. In addition, the numerical and analytical methods are in concordance with the results previously obtained in the experimental indentation of annealed aluminum A92030. Due to the introduction of the hardening factor, the new modular distribution is a suitable option for the analysis of indentation process. PMID:28772914

  3. Determining interfacial properties of submicron low-k films on Si substrate by using wedge indentation technique

    Science.gov (United States)

    Yeap, Kong Boon; Zeng, Kaiyang; Jiang, Haiyan; Shen, Lu; Chi, Dongzhi

    2007-06-01

    This article presents studies on using a wedge indentation technique to determine interfacial adhesion properties of low-k dielectric films, namely, methyl-silsesquioxane (MSQ) and black diamond (BD™)films, both on a Si substrate. Interfacial crack initiation and propagation processes in the MSQ/Si system are studied by using focused-ion-beam sectioning of the indentation impressions created by wedge tips with 90° and 120° of inclusion angles, respectively. Furthermore, the indentation induced stress is found to be proportional to the ratio of the indentation volume and the interface delamination crack volume for both plane strain and nonplane strain cases. With this analysis, the interface toughness of the MSQ/Si and BD/Si system, in terms of the strain energy release rate, is determined. The interface toughness for the MSQ/Si system is found to be a value of 1.89±0.28J/m2 for the 90° wedge tip indentation and 1.92±0.08J/m2 for the 120° wedge tip indentation. In addition, using the 120° wedge tip, the interface toughnesses of the BD films on the Si substrate with 200 and 500nm thicknesses are found to be the values of 6.62±1.52 and 6.35±2.27J/m2, respectively.

  4. On the Robustness of Poverty Predictors

    DEFF Research Database (Denmark)

    Arndt, Channing; Nhate, Virgulino; Silva, Patricia Castro Da

    Monitoring of poverty requires timely household budget data. However, such data are not available as frequently as needed for policy purposes. Recently, statistical methods have emerged to predict poverty overtime by combining detailed household consumption and expenditure data with more frequent...... data collected from other surveys. In this paper we compare poverty predictions for Mozambique using different source data to test the robustness of the predicted poverty statistics. A critical element in this exercise of predicting poverty overtime is the stability of the parameters that determine...... household consumption. We find that the assumption of stable consumption determinants does not hold for Mozambique during the time period examined. We also examine what drives the resulting predicted poverty statistics. The paper then considers the policy implications of these findings for Mozambique...

  5. SPATIAL DISTRIBUTION OF POVERTY AT DIFFERENT SCALES

    Directory of Open Access Journals (Sweden)

    Gandhi PAWITAN

    2010-01-01

    Full Text Available Poverty mapping is usually developed from some sources of data, such as from census and survey data. In some practical application, the poverty was measured usually by household income or expenditure of daily basic consumption. Using different scales and zoning on a particular set of spatial data may leads to problems in interpreting the results. In practice, organizations publish statistics and maps at a particular area level. Minot and Baulch (2005a discussed some consequences of using aggregated level data in poverty mapping, which may affect the validity of the output. The key point of this paper is to compare spatial distribution of the poverty at two different scale, which is the province and district level. How the spatial distribution of the poverty at province level can be use to infer the distribution at the district level. The geographical weighted regression will be applied, and the poverty data of Vietnam will be used as an illustration.

  6. OPPORTUNITY ESTIMATION OF OPTICAL METHOD APPLICATION IN PROBLEM OF KINEMATIC CHARACTERISTICS REGISTRATION OF DYNAMIC INDENTING PROCESS

    Directory of Open Access Journals (Sweden)

    Evgeniya I. Ivanova

    2017-07-01

    Full Text Available Subject of Research. A stereoscopic method of technical vision is proposed for recording the kinematic characteristics of the dynamic indentation process in determining the physico-mechanical properties of materials. The proposed method makes it possible to determine the values of the indenter motion speed with high accuracy. Method. The method is based on the use of two high-speed video cameras immovably fixed on one flat platform. Cameras allow for synchronous recording of the indentation process. The objectives and orientation of cameras in the stereo system provide intersection of the visual fields and the required depth of the image space field. Measurement of the movement speed is performed by triangulation method. The distance between the conjugate points of the recorded object on the stereo images is inversely proportional to the distance between the pair of cameras and the corresponding point of the object in the three-dimensional space. Based on the analysis of images obtained by spatially separated cameras, the coordinates of the object point are determined. Main Results. The experimental setup consisted of two high-speed monochrome camcorders Evercam 4000-32-M, rigidly fixed through stereo. Synchronous recording was kept at a speed of 4000 frames/s with a resolution of 1280 × 860 pixels. The indenter was made in the form of a steel ball with a mass of 230 g with a diameter of 38 mm and fell onto an aluminum disk 10 mm thick from a height of 310 mm. Video images from cameras were transferred to a personal computer for processing. The analysis of the obtained data was carried out in the MATLAB system with the help of a specially written software module. The sensitivity of the proposed method made it possible to determine confidently the values of the maximum approach speed of a steel ball equal to 2.39 m/s and a rebound velocity of 1.2 m/s. The random component of the method error did not exceed 2.5%. Practical Relevance. The

  7. Lower plate serpentinite diapirism in the Calabrian Arc subduction complex.

    Science.gov (United States)

    Polonia, A; Torelli, L; Gasperini, L; Cocchi, L; Muccini, F; Bonatti, E; Hensen, C; Schmidt, M; Romano, S; Artoni, A; Carlini, M

    2017-12-19

    Mantle-derived serpentinites have been detected at magma-poor rifted margins and above subduction zones, where they are usually produced by fluids released from the slab to the mantle wedge. Here we show evidence of a new class of serpentinite diapirs within the external subduction system of the Calabrian Arc, derived directly from the lower plate. Mantle serpentinites rise through lithospheric faults caused by incipient rifting and the collapse of the accretionary wedge. Mantle-derived diapirism is not linked directly to subduction processes. The serpentinites, formed probably during Mesozoic Tethyan rifting, were carried below the subduction system by plate convergence; lithospheric faults driving margin segmentation act as windows through which inherited serpentinites rise to the sub-seafloor. The discovery of deep-seated seismogenic features coupled with inherited lower plate serpentinite diapirs, provides constraints on mechanisms exposing altered products of mantle peridotite at the seafloor long time after their formation.

  8. Dehydration-driven topotaxy in subduction zones

    Science.gov (United States)

    Padrón-Navarta, José Alberto; Tommasi, Andréa; Garrido, Carlos J.

    2014-05-01

    Mineral replacement reactions play a fundamental role in the chemistry and the strength of the lithosphere. When externally or internally derived fluids are present, interface-coupled dissolution-precipitation is the driving mechanism for such reactions [1]. One of the microstructural features of this process is a 3D arrangement of crystallographic axes across internal interfaces (topotaxy) between reactant and product phases. Dehydration reactions are a special case of mineral replacement reaction that generates a transient fluid-filled porosity. Among others, the dehydration serpentinite is of special relevance in subduction zones because of the amount of fluids involved (potentially up to 13 wt.%). Two topotatic relationships between olivine and antigorite (the serpentine mineral stable at high temperature and pressure) have been reported in partially hydrated mantle wedge xenoliths [2]. Therefore, if precursor antigorite serpentine has a strong crystallographic preferred orientation (CPO) its dehydration might result in prograde peridotite with a strong inherited CPO. However for predicting the importance of topotactic reactions for seismic anisotropy of subduction zones we also need to consider the crystallization orthopyroxene + chlorite in the prograde reaction and, more importantly, the fact that this dehydration reaction produces a transient porosity of ca. 20 % vol. that results in local fluctuations of strain during compaction and fluid migration. We address this issue by a microstructural comparison between the CPO developed in olivine, orthopyroxene and chlorite during high-pressure antigorite dehydration in piston cylinder experiments (at 750ºC and 20 kbar and 1000ºC and 30 kbar, 168 h) and that recorded in natural samples (Cerro del Almirez, Betic Cordillera, Spain). Experimentally developed CPOs are strong. Prograde minerals show a significant inheritance of the former antigorite foliation. Topotactic relations are dominated by (001)atg//(100)ol

  9. Cultural diversity and anti-poverty policy.

    Science.gov (United States)

    Lamont, Michèle; Small, Mario Luis

    2010-01-01

    This article examines how anti-poverty policy has considered the role of culture and how it ought to do so. While some have explained poverty as a function of the presumed cultural deficiency or distinctiveness of the poor, we suggest that these explanations have not been convincing and that policy requires a broader and more sophisticated understanding of the relationship between culture and behaviour. In fact, we suggest that cultural differences may be positively employed in comprehensive anti-poverty strategies.

  10. The measurement of time and income poverty

    OpenAIRE

    Zacharias, Ajit

    2011-01-01

    Official poverty thresholds are based on the implicit assumption that the household with poverty-level income possesses sufficient time for household production to enable it to reproduce itself as a unit. Several authors have questioned the validity of the assumption and explored alternative methods to account for time deficits in the measurement of poverty. I critically review the alternative approaches within a unified framework to highlight the commonalities and relative merits of individu...

  11. The Impact of Poverty on Corruption

    OpenAIRE

    ÜNVER, Mustafa; KOYUNCU, Julide Yalçınkaya

    2016-01-01

    Abstract. This paper examines the effect of poverty on corruption using annual unbalanced panel data analysis on 154 countries from 2000 to 2013. In the models, we use corruption measures from three alternative sources as a dependent variable while independent variables are five different poverty measures. In addition, this study has some control variables, such as foreign direct investment (FDI), trade openness, inflation rate and democracy level. According to empirical results, all poverty ...

  12. On Capability Approach, Poverty and Corruption

    OpenAIRE

    Daojiu Hu

    2014-01-01

    The core of development is to face up with the challenge of the issue of poverty, which directly is associated with the ultimate goal of social, political and economic development. If the poverty has not been properly handled, development will be inefficient and unsustainable. This paper briefly indicates the main idea of Amartya Sen’s capability approach, then utilizing the approach to analyze poverty and the bottleneck in dealing such issues. It illustrates the inter-relationship of capabil...

  13. Incorporating Gender into Poverty Reduction Strategies

    OpenAIRE

    Moheyuddin, Ghulam

    2005-01-01

    This paper Explain the rationale for incorporating gender in PRS and describing the three-step process to incorporating gender into poverty reduction strategies. It also analyzes the different tools and methods available to identify gender issues in poverty analysis? And discuss the differences between the poverty constraints faced by the women and by men. The paper suggests methods that can be used to analyze gender differences? Finally the paper explains the Pakistan’s country-specific exp...

  14. On biodiversity conservation and poverty traps

    Science.gov (United States)

    Barrett, Christopher B.; Travis, Alexander J.; Dasgupta, Partha

    2011-01-01

    This paper introduces a special feature on biodiversity conservation and poverty traps. We define and explain the core concepts and then identify four distinct classes of mechanisms that define important interlinkages between biodiversity and poverty. The multiplicity of candidate mechanisms underscores a major challenge in designing policy appropriate across settings. This framework is then used to introduce the ensuing set of papers, which empirically explore these various mechanisms linking poverty traps and biodiversity conservation. PMID:21873176

  15. The dynamics of poverty and crime

    Directory of Open Access Journals (Sweden)

    Haiyun Zhao

    2014-10-01

    Full Text Available Poverty and crime are two maladies that plague metropolitan areas.The economic theory of crime [1] demonstrates a direct correlation between poverty and crime.The model considered in this study seeks to examine the dynamics of the poverty-crime system through stability analysis of a system of ordinary differential equations in order to identify cost-effective strategies to combat crime in metropolises.

  16. Multidimensional Poverty and Health Status as a Predictor of Chronic Income Poverty.

    Science.gov (United States)

    Callander, Emily J; Schofield, Deborah J

    2015-12-01

    Longitudinal analysis of Wave 5 to 10 of the nationally representative Household, Income and Labour Dynamics in Australia dataset was undertaken to assess whether multidimensional poverty status can predict chronic income poverty. Of those who were multidimensionally poor (low income plus poor health or poor health and insufficient education attainment) in 2007, and those who were in income poverty only (no other forms of disadvantage) in 2007, a greater proportion of those in multidimensional poverty continued to be in income poverty for the subsequent 5 years through to 2012. People who were multidimensionally poor in 2007 had 2.17 times the odds of being in income poverty each year through to 2012 than those who were in income poverty only in 2005 (95% CI: 1.23-3.83). Multidimensional poverty measures are a useful tool for policymakers to identify target populations for policies aiming to improve equity and reduce chronic disadvantage. Copyright © 2014 John Wiley & Sons, Ltd.

  17. Poverty and inequality in South Africa and the world | Govender ...

    African Journals Online (AJOL)

    This article begins with a discussion of various definitions and concepts of poverty and inequality. It then distinguishes between objective and subjective concepts of poverty, temporary versus chronic poverty, and absolute versus relative poverty. The concept of inequality is discussed and compared with that of poverty.

  18. Women in Poverty: Experience from Limpopo Province, South Africa ...

    African Journals Online (AJOL)

    This study focuses on the extent of African women poverty level including poverty reduction strategies used in South Africa. The scope of the study was broadened to include poverty –related issues focusing on the current patterns of poverty and inequality affecting African women. African women related poverty problems in ...

  19. PARADOX OF POVERTY IN VILLAGE Ubud

    Directory of Open Access Journals (Sweden)

    I Nyoman Sudipa

    2014-08-01

    Full Text Available The research raises poverty as a social reality in the middle of the sparkling tourism in Ubud Village . This study focused on the discussion : ( 1 why is there poverty , ( 2 what efforts the government and other agencies to reduce poverty , and ( 3 how the effects of poverty are emerging . This study used qualitative methods . Data obtained through observation , interviews , and documentation . The results showed , poverty in the village of Ubud , which is caused by external factors such as government policy reference data, which is not clear , the lack of proper diagnosis , addressing poverty is not integrated and overlapping , and the failure of tourism development policies . External factors supported internal factors , namely the economic constraints , resources , and socio-cultural pressures , lifestyle , consumer behavior , asset ownership , land , and the cost of customs and rituals . Government efforts made ??through the program financially and non- financially poverty reduction through policy or regulation , mentoring , and training . NGOs make efforts to non - financially as a companion , mediator , facilitator and prepare sosial.Dampak mapping poverty in the village of Ubud is to reduce public confidence in the government , social conflict , and economic conflicts . The impact on tourism is tourism failing to provide social welfare . The impact for the community is resulting in social inequality , conflict , rising crime , and the inheritance of poverty

  20. Causal Attributions for Poverty in Developing Countries

    Directory of Open Access Journals (Sweden)

    José Juan Vázquez

    2009-07-01

    Full Text Available This paper analyzes attributional differences about causes of poverty in the less developed countries, among Nicaraguan ("actors" and Spanish ("observers" undergraduates. A self–applied questionnaire was used. It included socio–demographic questions and an adaptation of the "Causes of Third World Poverty Questionnaire" (CTWPQ. Results show agreement between Spanish and Nicaraguan in attributions about the main causes of poverty in the less developed countries, although there are differences about the perception of the incidence of the different causes in that situation. Nicaraguan students consider, as causes of poverty, more dispositional attributes about the population in those countries.

  1. Does Inequality Matter for Poverty Reduction? Evidence from Pakistan’s Poverty Trends

    OpenAIRE

    Haroon Jamal

    2006-01-01

    The paper explores the linkages between poverty, growth and inequality in the context of Pakistan. Time series macro data are used for the period 1979 to 2002. Consistent poverty and inequality measures are interpolated to facilitate the estimation of poverty elasticity with respect to growth and inequality in a multivariate regression framework. The paper also attempts to find out macroeconomic and structural correlates of inequality. The empirical findings—high poverty elasticity with respe...

  2. Poverty Estimating Poverty for Indigenous Groups by Matching Census and Survey Data

    OpenAIRE

    Claudio Agostini; Phillip Brown; Andrei Roman

    2008-01-01

    It is widely held that indigenous Chileans experience greater rates of poverty and indigence than non-indigenousChileans, yet the evidence to date has been based on surveys that are not representative by ethnicity. In this paper,we use poverty mapping methodologies that are typically applied to geography to develop statistically preciseestimates of poverty, indigence, poverty gaps, and indigence gaps for each of the eight indigenous groupsrecognized by Chilean law. We find that indigenous peo...

  3. Child Poverty: Concepts and Measurement

    Directory of Open Access Journals (Sweden)

    Alberto Minujin and Others

    2008-03-01

    Full Text Available This paper presents and discusses different concepts of child poverty, alternative definitions of children living in poverty, and measurement efforts in this regard. It addresses such questions as: who are the children living in poverty? Is the issue of children living in poverty recognized by and incorporated into anti-poverty strategies? Have governments, civil society organizations and international organizations identified and adopted policies to reduce child poverty? And is the situation of girls living in poverty taken into account? Several organizations have recently adopted human rights-based approaches to defining children living in poverty, and these definitions are included here. In general, however, the assessment finds that there is a lack of consideration of children’s issues in the debate on poverty. The lack of visibility has negative implications for anti-poverty strategies, which seldom consider that children and their rights are central to their design and implementation. In this paper, we argue that the lack of conceptualization and debate on the specificities of child poverty has enormous consequences for policy and, vice versa, that the income generation and sectoral focus of poverty reduction policies discourages a holistic response to children and families. مقاله حاضر مفاهیم مختلف فقر کودکان، تعاریف دیگر برای کودکانی که در فقر به سر می‌برند و تلاش‌های لازم برای نحوه اندازه‌گیری فقر را بررسی و ارائه می‌نماید. در این مقاله به این سؤالات پرداخته خواهد شد: کودکانی که در فقر به سر می‌برند چه کسانی هستند؟ آیا موضوع کودکانی که در فقر زندگی می‌کنند در استراتژی‌های ضد فقر گنجانده شده است؟ آیا دولت‌ها، سازمان‌های جامعه مدنی و

  4. The Cascadia Subduction Zone: two contrasting models of lithospheric structure

    Science.gov (United States)

    Romanyuk, T.V.; Blakely, R.; Mooney, W.D.

    1998-01-01

    The Pacific margin of North America is one of the most complicated regions in the world in terms of its structure and present day geodynamic regime. The aim of this work is to develop a better understanding of lithospheric structure of the Pacific Northwest, in particular the Cascadia subduction zone of Southwest Canada and Northwest USA. The goal is to compare and contrast the lithospheric density structure along two profiles across the subduction zone and to interpet the differences in terms of active processes. The subduction of the Juan de Fuca plate beneath North America changes markedly along the length of the subduction zone, notably in the angle of subduction, distribution of earthquakes and volcanism, goelogic and seismic structure of the upper plate, and regional horizontal stress. To investigate these characteristics, we conducted detailed density modeling of the crust and mantle along two transects across the Cascadia subduction zone. One crosses Vancouver Island and the Canadian margin, the other crosses the margin of central Oregon.

  5. Oceanic anoxic events, subduction style and molybdenum mineralization

    Directory of Open Access Journals (Sweden)

    Wei-dong Sun

    2016-09-01

    Molybdenum deposits of the Eastern Pacific margin can be classified into three types: porphyry-Cu-Mo, high-F porphyry and low-F porphyry-Mo deposits. Large and superlarge porphyry-Cu-Mo deposits are usually associated with ridge subductions, and thus formed through partial melting of subducted oceanic crust and metamorphosed Mo-rich sedimentary material due to subduction erosion. The high-F porphyry-Mo deposits (e.g., Climax-type were likely formed by partial melting of subducted and thus metamorphosed Mo-enriched sediments during slab rollback (usually associated with A-type granite. Low-F porphyry-Mo deposits were formed through direct partial melting of metamorphosed Mo-enriched sediments entrained into the mantle wedge through subduction erosion at slightly shallower depths (usually associated with arc granite. Porphyry-Cu (Au deposits in the southwest Pacific margin are all associated with subduction of backarc basins younger than the last OAE (55.8 Ma. Therefore, porphyry Cu (Au deposits in the southwest Pacific margin have no economic levels of Mo. The oxygen fugacity of northwest Pacific is lower than ΔFMQ +2, which inhibits the formation of porphyry deposits.

  6. Impact-driven subduction on the Hadean Earth

    Science.gov (United States)

    O'Neill, C.; Marchi, S.; Zhang, S.; Bottke, W.

    2017-10-01

    Impact cratering was a dominant geologic process in the early Solar System that probably played an active role in the crustal evolution of the young terrestrial planets. The Earth's interior during the Hadean, 4.56 to 4 billion years ago, may have been too hot to sustain plate tectonics. However, whether large impacts could have triggered tectonism on the early Earth remains unclear. Here we conduct global-scale tectonic simulations of the evolution of the Earth through the Hadean eon under variable impact fluxes. Our simulations show that the thermal anomalies produced by large impacts induce mantle upwellings that are capable of driving transient subduction events. Furthermore, we find that moderate-sized impacts can act as subduction triggers by causing localized lithospheric thinning and mantle upwelling, and modulate tectonic activity. In contrast to contemporary subduction, the simulated localized subduction events are relatively short-lived (less than 10 Myr) with relatively thin, weak plates. We suggest that resurgence in subduction activity induced by an increased impact flux between 4.1 and 4.0 billion years ago may explain the coincident increase in palaeointensity of the magnetic field. We further suggest that transient impact-driven subduction reconciles evidence from Hadean zircons for tectonic activity with other lines of evidence consistent with an Earth that was largely tectonically stagnant from the Hadean into the Archaean.

  7. Poverty in a Rising Africa

    OpenAIRE

    Christiaensen, Luc; Gaddis, Isis; Dabalen, Andrew; Beegle, Kathleen

    2015-01-01

    Perceptions of Africa have changed dramatically. Viewed as a continent of wars, famines and entrenched poverty in the late 1990s, there is now a focus on “Africa rising” and an “African 21st century.” Two decades of unprecedented economic growth in Africa should have brought substantial improvements in well-being. Whether or not they did, remains unclear given the poor quality of the data, the nature of the growth process (especially the role of natural resources), conflicts that affect part ...

  8. The 100 faces of poverty

    OpenAIRE

    Vépy-Schlemmer, Éva

    2010-01-01

    Information about our world and society cannot be obtained through numbers only, even so because a significant segment of our current knowledge is conveyed through pictures and other visual signs. These are to complement our verbal codes and are capable of showing the human face of social reality, such as poverty, hidden beyond the maze of various charts and diagrams. The concept of “The poorest 100” was inspired by the top list of the 100 richest persons published every year; this unique...

  9. Climate change and fuel poverty

    OpenAIRE

    Simon Dresner; Paul Ekins

    2005-01-01

    The research examined the possible effects of rapid climate change on fuel poverty (needing to spend more than 10% of income to maintain a satisfactory level of warmth and other energy services in the home). One particular concern was the prospect that there might be a shutting off of the Gulf Stream, which warms Britain and the rest of north-western Europe. Computer simulations of the climate indicate that shutting down the Gulf Stream would cool England by about 3°C. Climate is not the only...

  10. Poverty | La pauvreté

    Directory of Open Access Journals (Sweden)

    2012-05-01

    Full Text Available Poverty Evolution, 1990–2010 (World Bank income categoriesEvolution de la pauvreté, 1990-2010 (catégories de revenus de la Banque mondialeSource: World Bank, World Bank GNI per Capita Operational Guidelines and Analytical Classifications, http://data.worldbank.org/about/country-classifications/a-short-history.Where the Poor Are, 2007–2008 (million of people living under USD 1.25/day, Purchasing Power Parity*Où sont les pauvres, 2007-2008 (millions de pauvres qui vivent avec moins de 1.25 U...

  11. Poverty dynamics in Germany: Evidence on the relationship between persistent poverty and health behavior.

    Science.gov (United States)

    Aue, Katja; Roosen, Jutta; Jensen, Helen H

    2016-03-01

    Previous studies have found poverty to be related to lower levels of health due to poor health behavior such as unhealthy eating, smoking or less physical activity. Longer periods of poverty seem to be especially harmful for individual health behavior. Studies have shown that poverty has a dynamic character. Moreover, poverty is increasingly regarded as being a multidimensional construct and one that considers more aspects than income alone. Against this background this paper analyzes the relationship between health behavior and persistent spells of income poverty as well as a combined poverty indicator using data of the German Socio-Economic Panel (2000-2010). Next to cross-sectional logistic regression models we estimate fixed-effects models to analyze the effect of persistent poverty on dietary behavior, tobacco consumption, and physical activity. Cross-sectional results suggest that persistent poverty is related to poor health behavior, particularly regarding tobacco consumption and physical activity. Results also show that multidimensional and dynamic aspects of poverty matter. Complementary panel analyses reveal negative effects for the combined poverty indicator only for dietary behavior in the total sample. However, by analyzing the sample by gender we identify further effects of persistent poverty on health behavior. The analyses show that not only do individuals in poverty but also those in precarious situations show health-damaging behavior more often. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. The Poverty Challenge: How Individual Decision-Making Behavior Influences Poverty

    NARCIS (Netherlands)

    Pennings, J.M.E.; Garcia, P.

    2005-01-01

    What drives poverty? We propose a research approach to study poverty by focusing on individual decision-making behavior in which the interaction between individual's innovativeness and time preference rate is crucial to begin understanding poverty. This approach enables policy makers to formulate

  13. Poverty PhDs: Funds of Knowledge, Poverty, and Professional Identity in Academia

    Science.gov (United States)

    Cutri, Ramona Maile; Manning, Jill Michelle; Chun, Marc

    2011-01-01

    In contrast to the common deficit approach, this self-study explores the relationship between the funds of knowledge possessed by people of poverty and their development of professional identity in academia. All three authors have moved beyond conditions of financial poverty, but all find that the mental conditions of poverty persist. We conclude…

  14. Do we understand the linkages between economic growth, poverty targets and poverty reduction?

    DEFF Research Database (Denmark)

    Casse, Thorkil; Jensen, Stig Eduard Breitenstein

    2009-01-01

    appears more obvious, social and political unrest in 2009 casts doubt on the reliability of the data. Indeed, it is probable that an increase in poverty contributed to the crisis in Madagascar. Furthermore, there a signs that in both countries poverty strategies are increasingly giving way to Poverty...

  15. Indentation studies on Y[sub 2]O[sub 3]-stabilized ZrO[sub 2]; 2: Toughness determination from stable growth of indentation-induced cracks

    Energy Technology Data Exchange (ETDEWEB)

    Dransmann, G.W.; Steinbrech, R.W. (Inst. fuer Reaktorwerkstoffe, Juelich (Germany)); Pajares, A.; Guiberteau, F. (Univ. de Extremadura, Badajoz (Spain). Facultad de Ciencias); Dominguez-Rodriguez, A. (Univ. de Sevilla (Spain). Dept. de Fisic Materia Condensada); Heuer, A.H. (Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Materials Science and Engineering)

    1994-05-01

    Stable indentation cracks were grown in four-point bend tests to study the fracture toughness of two Y[sub 2]O[sub 3]-stabilized ZrO[sub 2] ceramics containing 3 and 4 mol% Y[sub 2]O[sub 3]. By combining microscopic in situ stable crack growth observations at discrete stresses with crack profile measurements, the dependence of toughness on crack extension was determined from crack extension plots, which graphically separate the crack driving residual stress intensity and applied stress intensity factors. Both materials exhibit steeply rising R-curves, with a plateau toughness of 4.5 and 3.1 MPa[center dot]m[sup 1/2] for the 3- and 4-mol% materials, respectively. The magnitude of the plateau toughness reflects the fraction of tetragonal grain contributing to transformation toughening.

  16. Transient poverty, poverty dynamics, and vulnerability to poverty: An empirical analysis using a balanced panel from rural China

    Science.gov (United States)

    Ward, Patrick S.

    2015-01-01

    China’s economic reforms starting in the late 1970s have resulted in rapid economic growth, with annual growth in gross domestic product averaging greater than 10 percent per year for more than thirty years. Accompanying this rapid growth in national accounts have been rapid and widespread reductions in poverty. With these reductions in poverty, however, there has often been observed an increase in income inequality, both between as well as within rural and urban sectors. This rising income gap challenges the notion that economic reforms in China have been as successful as the poverty statistics would suggest. In this paper, we suggest that an alternative view would be to consider the effects of these reforms on changing the chronic nature of poverty and reducing household vulnerability to poverty. Using a balanced panel from rural China from 1991 through 2006, we find that most poverty among our sample has shifted from being chronic in nature to being transient, with households either shifting into a state of being non-poor moving in and out of poverty. Among our sample, vulnerability to poverty has been declining over time, but the declines are not uniform over time or space. We decompose household vulnerability status into two proximate causes: low expected income and high income variability, finding vulnerability increasingly due to income variability. Additionally, we demonstrate that vulnerable households have very different characteristics than non-vulnerable households. PMID:26855470

  17. Multiscale Architecture of a Subduction Complex and Insight into Large-scale Material Movement in Subduction Systems

    Science.gov (United States)

    Wakabayashi, J.

    2014-12-01

    The >1000 km by >100 km Franciscan complex of California records >100 Ma of subduction history that terminated with conversion to a transform margin. It affords an ideal natural laboratory to study the rock record of subduction-interface and related processes exhumed from 10-70 km. The Franciscan comprises coherent and block-in-matrix (mélange) units forming a nappe stack that youngs structurally downward in accretion age, indicating progressive subduction accretion. Gaps in accretion ages indicate periods of non-accretion or subduction erosion. The Franciscan comprises siliciclastic trench fill rocks, with lesser volcanic and pelagic rocks and serpentinite derived from the downgoing plate, as well as serpentinite and felsic-intermediate igneous blocks derived as detritus from the upper plate. The Franciscan records subduction, accretion, and metamorphism (including HP), spanning an extended period of subduction, rather than a single event superimposed on pre-formed stratigraphy. Melanges (serpentinite and siliciclastic matrix) with exotic blocks, that include high-grade metamorphic blocks, and felsic-intermediate igneous blocks from the upper plate, are mostly/entirely of sedimentary origin, whereas block-in-matrix rocks formed by tectonism lack exotic blocks and comprise disrupted ocean plate stratigraphy. Mélanges with exotic blocks are interbedded with coherent sandstones. Many blocks-in-melange record two HP burial events followed by surface exposure, and some record three. Paleomegathrust horizons, separating nappes accreted at different times, appear restricted to narrow fault zones of structures, are accommodated by discrete faults or narrow shear zones, rather than by significant penetrative strain. Exhumation of Franciscan HP units, both coherent and mélange, was accommodated by significant extension of the overlying plate, and possibly extension within the subduction complex, with cross-sectional extrusion, and like subduction burial, took place at

  18. Poverty, development, and Himalayan ecosystems.

    Science.gov (United States)

    Sandhu, Harpinder; Sandhu, Sukhbir

    2015-05-01

    The Himalayas are rich in biodiversity but vulnerable to anthropogenic pressures. They are also host to growing number of rural poor who are dependent on forest and ecosystem services for their livelihood. Local and global efforts to integrate poverty alleviation and biodiversity conservation in the Himalayas remain elusive so far. In this work, we highlight two key impediments in achieving sustainable development in the Himalayas. On the positive side, we also highlight the work of Ashoka Trust for Research in Ecology and the Environment (ATREE), a research organization based in India that seeks to integrate biodiversity concerns with livelihood security. For impediments, we draw on two examples from the Darjeeling district, India, in Eastern Himalayan region to illustrate how development organizations are failing to simultaneously address poverty and environmental issues. Based on the success of ATREE, we then propose a conceptual framework to integrate livelihood generating activities with sustainable and equitable development agenda. We recommend developing a Hindu-Kush Himalayan Ecosystem Services Network in the region to formulate a strategy for further action. We conclude by offering measures to address the challenge of integrating livelihood and environment issues through this network.

  19. Deep mantle seismic heterogeneities in Western Pacific subduction zones

    Science.gov (United States)

    Bentham, H. L. M.; Rost, S.

    2012-04-01

    In recent years array seismology has been used extensively to image the small scale (~10 km) structure of the Earth. In the mantle, small scale structure likely represents chemical heterogeneity and is essential in our understanding of mantle convection and especially mantle mixing. As subduction is the main source of introducing crustal material into the Earth's mantle, it is of particular interest to track the transport of subducted crust through the mantle to resolve details of composition and deformation of the crust during the subduction process. Improved knowledge of subduction can help provide constraints on the mechanical mixing process of crustal material into the ambient mantle, as well as constraining mantle composition and convection. This study uses seismic array techniques to map seismic heterogeneities associated with Western Pacific subduction zones, where a variety of slab geometries have been previously observed. We use seismic energy arriving prior to PP, a P-wave underside reflection off the Earth's surface halfway between source and receiver, to probe the mantle for small-scale heterogeneities. PP precursors were analysed at Eielson Array (ILAR), Alaska using the recently developed Toolkit for Out-of-Plane Coherent Arrival Tracking (TOPCAT) algorithm. The approach combines the calculated optimal beampower and an independent semblance (coherency) measure, to improve the signal-to-noise ratio of coherent arrivals. 94 earthquakes with sufficient coherent precursory energy were selected and directivity information of the arrivals (i.e. slowness and backazimuth) was extracted from the data. The scattering locations for 311 out-of-plane precursors were determined by ray-tracing and minimising the slowness, backazimuth and differential travel time misfit. Initial analyses show that deep scattering (>1000 km) occurs beneath the Izu-Bonin subduction zone, suggesting that subducted crust does continue into the lower mantle in this location. Other

  20. Subduction initiation and Obduction: insights from analog models

    Science.gov (United States)

    Agard, P.; Zuo, X.; Funiciello, F.; Bellahsen, N.; Faccenna, C.; Savva, D.

    2013-12-01

    Subduction initiation and obduction are two poorly constrained geodynamic processes which are interrelated in a number of natural settings. Subduction initiation can be viewed as the result of a regional-scale change in plate convergence partitioning between the set of existing subduction (and collision or obduction) zones worldwide. Intraoceanic subduction initiation may also ultimately lead to obduction of dense oceanic "ophiolites" atop light continental plates. A classic example is the short-lived Peri-Arabic obduction, which took place along thousands of km almost synchronously (within ~5-10 myr), from Turkey to Oman, while the subduction zone beneath Eurasia became temporarily jammed. We herein present analog models designed to study both processes and more specifically (1) subduction initiation through the partitioning of deformation between two convergent zones (a preexisting and a potential one) and, as a consequence, (2) the possible development of obduction, which has so far never been modeled. These models explore the mechanisms of subduction initiation and obduction and test various triggering hypotheses (i.e., plate acceleration, slab crossing the 660 km discontinuity, ridge subduction; Agard et al., 2007). The experimental setup comprises an upper mantle modelled as a low-viscosity transparent Newtonian glucose syrup filling a rigid Plexiglas tank and high-viscosity silicone plates. Convergence is simulated by pushing on a piston at one end of the model with plate tectonics like velocities (1-10 cm/yr) onto (i) a continental margin, (ii) a weakness zone with variable resistance and dip (W), (iii) an oceanic plate - with or without a spreading ridge, (iv) a subduction zone (S) dipping away from the piston and (v) an upper active continental margin, below which the oceanic plate is being subducted at the start of the experiment (as for the Oman case). Several configurations were tested over thirty-five parametric experiments. Special emphasis was

  1. Cultural Diversity and Anti-Poverty Policy

    Science.gov (United States)

    Lamont, Michele; Small, Mario Luis

    2010-01-01

    This article examines how anti-poverty policy has considered the role of culture and how it ought to do so. While some have explained poverty as a function of the presumed cultural deficiency or distinctiveness of the poor, we suggest that these explanations have not been convincing and that policy requires a broader and more sophisticated…

  2. Disadvantage and Poverty in Rural Scotland.

    Science.gov (United States)

    McSwan, David

    1996-01-01

    A 1993 survey of 500 households in rural Scotland, followed by 120 interviews, found that poverty was widespread; subjective assessments of poverty contradicted objective definitions in that people were satisfied with rural life; acceptance of government benefits was low; rental housing was scarce; employment opportunities were limited, especially…

  3. Multidimensional poverty and child survival in India.

    Directory of Open Access Journals (Sweden)

    Sanjay K Mohanty

    Full Text Available BACKGROUND: Though the concept of multidimensional poverty has been acknowledged cutting across the disciplines (among economists, public health professionals, development thinkers, social scientists, policy makers and international organizations and included in the development agenda, its measurement and application are still limited. OBJECTIVES AND METHODOLOGY: Using unit data from the National Family and Health Survey 3, India, this paper measures poverty in multidimensional space and examine the linkages of multidimensional poverty with child survival. The multidimensional poverty is measured in the dimension of knowledge, health and wealth and the child survival is measured with respect to infant mortality and under-five mortality. Descriptive statistics, principal component analyses and the life table methods are used in the analyses. RESULTS: The estimates of multidimensional poverty are robust and the inter-state differentials are large. While infant mortality rate and under-five mortality rate are disproportionately higher among the abject poor compared to the non-poor, there are no significant differences in child survival among educationally, economically and health poor at the national level. State pattern in child survival among the education, economical and health poor are mixed. CONCLUSION: Use of multidimensional poverty measures help to identify abject poor who are unlikely to come out of poverty trap. The child survival is significantly lower among abject poor compared to moderate poor and non-poor. We urge to popularize the concept of multiple deprivations in research and program so as to reduce poverty and inequality in the population.

  4. Poverty - The road ahead. A theological perspective

    Directory of Open Access Journals (Sweden)

    P. G. J. Meiring

    1993-08-01

    Full Text Available The article focuses on the role of the Church in combating poverty in South Africa. After a brief discussion of Biblical perspectives on poverty, an overview of the involvement of the Church throughout history, especially during the second half of the 20th century, is given.

  5. Overcoming Poverty as a Collective Obligation: Christian ...

    African Journals Online (AJOL)

    Religion Dept

    We must realize that much as there is need to stress the spiritual dimension of poverty which is important for ... often constitute a great hindrance to the poor liberating themselves from the bondage of poverty. It is never an over ..... The Challenge Facing the Church in William. P. & Perrotta, K. (eds.) Christianity Confronts ...

  6. On Capability Approach, Poverty and Corruption

    Directory of Open Access Journals (Sweden)

    Daojiu Hu

    2014-04-01

    Full Text Available The core of development is to face up with the challenge of the issue of poverty, which directly is associated with the ultimate goal of social, political and economic development. If the poverty has not been properly handled, development will be inefficient and unsustainable. This paper briefly indicates the main idea of Amartya Sen’s capability approach, then utilizing the approach to analyze poverty and the bottleneck in dealing such issues. It illustrates the inter-relationship of capability, poverty and corruption, and demonstrates that corruption is both the cause and the consequence of poverty and the failure of capability. When there corruption comes, the essential power to alleviate and eliminate poverty such as political accountability, transparency, engagement and openness are all spoiled and even wiped off. Political accountability, transparence, engagement are of great importance to both anti-corruption and poverty and promotion of capability. Economic aid for the poor and needy should be reinforced by fostering and promoting the capability of the poor and needy, so that the purpose of eliminating poverty and corruption could be achieved.

  7. Grassroots Economic Development, Social Justice and Poverty ...

    African Journals Online (AJOL)

    The article defines, albeit briefly, what constitutes poverty, and factors that contribute to abject poverty: some of which include ignorance, lack of social facilities, dependence, disease, corruption, etc. The article surmises that if there is close relationship and interface between grassroots economic development, social justice, ...

  8. Poverty and Social Exclusion in India : Adivasis

    OpenAIRE

    Das, Maitreyi Bordia; Kapoor Mehta, Soumya

    2012-01-01

    This brief describes the poverty and social exclusion of the tribal groups in India. Tribal groups or Adivasis are considered to be the earliest inhabitants of India. While India is widely considered a success story in terms of growth and poverty reduction, Adivasis in 2004–2005 were twenty years behind the average. Scheduled Tribes are often conflated with Scheduled Castes in the develop...

  9. Grassroots Economic Development, Social Justice and Poverty ...

    African Journals Online (AJOL)

    This article discusses the relationship that exists between grassroots economic development, social justice, and poverty reduction. It argues that social justice is a central component for the achievement of grassroots economic development, and in that process making it possible to reduce, and even eradicates, poverty.

  10. Diagnosing poverty in Northern Ghana: institutional versus ...

    African Journals Online (AJOL)

    The paper attempts a diagnosis of poverty at institutional and community levels. This diagnosis entails an examination and comparison of various articulations of poverty in the formal, official and/or so-called high places of government and global institutions as well as at the grassroots such as households, individuals and ...

  11. European welfare regimes: Political orientations versus poverty

    Directory of Open Access Journals (Sweden)

    Josifidis Kosta

    2011-01-01

    Full Text Available This inquiry analyzes how political orientations shape welfare states and labour market institutions when seeking to reduce poverty. In order to identify effects of these two key variables, we conduct a panel regression analysis that includes two poverty measures: poverty rates before and after social spending. This inquiry considers 14 EU countries, and in the period from 1995 to 2008, which are grouped according to welfare state regimes. We consider Social Democratic, Corporatist, Mediterranean and Liberal welfare state regimes. Panel regression results indicate that political orientation engenders no significant statistically measurable effects on poverty rates before social spending. Effects register, however, as significant when considering poverty rates after social spending. With respect to the first set of results, we advance two key explanations. First, we note a longer period of time is necessary in order to observe actual effects of political orientation on market generated poverty. Second, political parties with their respective programs do not register as influential enough to solve social problems related to income distribution when taken alone. Influences register as indirect and are expressed through changes in employment rates and social spending. The second set of results support the hypothesis that a selected political regime does indeed contribute to poverty reduction. In sum, political orientation and political regime does indeed affect poverty through welfare state institutions, as well as through labour market institutions.

  12. Energy Poverty in Europe: A Multidimensional Approach

    Directory of Open Access Journals (Sweden)

    Carlo Andrea Bollino

    2017-12-01

    Full Text Available With the European Commission’s “Third Energy Package”, the challenges posed by energy poverty have been recently acknowledged by European legislation. The paper develops a synthetic indicator of energy poverty for the purpose of assessing households’ well-being across different domains of inequality in access to energy services and to a healthy domestic environment. These dimensions are broadly defined in terms of energy affordability and thermal efficiency, two of the main manifestations of energy poverty. The analysis focuses on Europe and expands on existing economic literature by employing a fuzzy analysis for the definition of a multidimensional energy poverty index, which is then used to investigate the role of individual and household characteristics in shaping energy poverty. We find that during the European crisis energy poverty has been more stable than monetary poverty, and that thermal efficiency plays a crucial role in shaping individual and countries’ average degrees of energy poverty. JEL codes: I32; Q41; D10; D63

  13. General Music and Children Living in Poverty

    Science.gov (United States)

    McAnally, Elizabeth Ann

    2013-01-01

    A review of recent writing makes the case that children living in poverty (urban, rural, or other) are more in jeopardy now than ever. As teachers attest and research asserts, poverty affects children in profound, complicated, and lasting ways. However, the general music program is uniquely positioned to meet children’s needs, especially those…

  14. Programmes and Strategies Targeting Gender and Poverty ...

    African Journals Online (AJOL)

    This article emanates from a broader research project that sought to explore 'new models' and innovative ways of thinking and dealing with poverty. Using an interpretive research paradigm and multiple case studies, this article seeks to establish if a common understanding of poverty exists within government departments.

  15. Terrorism and poverty: double trouble for macroeconomic ...

    African Journals Online (AJOL)

    This article investigates poverty and terrorism as allies in hindering economic growth in African countries. This study uses data for 22 African countries from 1970 to 2013 i.e. 44 years. Data for terrorism, poverty and national income is taken from GTD and WDI. Panel cointegration techniques of dynamic fixed effect, mean ...

  16. Multidimensional Poverty and Child Survival in India

    Science.gov (United States)

    Mohanty, Sanjay K.

    2011-01-01

    Background Though the concept of multidimensional poverty has been acknowledged cutting across the disciplines (among economists, public health professionals, development thinkers, social scientists, policy makers and international organizations) and included in the development agenda, its measurement and application are still limited. Objectives and Methodology Using unit data from the National Family and Health Survey 3, India, this paper measures poverty in multidimensional space and examine the linkages of multidimensional poverty with child survival. The multidimensional poverty is measured in the dimension of knowledge, health and wealth and the child survival is measured with respect to infant mortality and under-five mortality. Descriptive statistics, principal component analyses and the life table methods are used in the analyses. Results The estimates of multidimensional poverty are robust and the inter-state differentials are large. While infant mortality rate and under-five mortality rate are disproportionately higher among the abject poor compared to the non-poor, there are no significant differences in child survival among educationally, economically and health poor at the national level. State pattern in child survival among the education, economical and health poor are mixed. Conclusion Use of multidimensional poverty measures help to identify abject poor who are unlikely to come out of poverty trap. The child survival is significantly lower among abject poor compared to moderate poor and non-poor. We urge to popularize the concept of multiple deprivations in research and program so as to reduce poverty and inequality in the population. PMID:22046384

  17. The Impact of Mass Incarceration on Poverty

    Science.gov (United States)

    DeFina, Robert; Hannon, Lance

    2013-01-01

    During the past 30 years, U.S. poverty has remained high despite overall economic growth. At the same time, incarceration rates have risen by more than 300%, a phenomenon that many analysts have referred to as mass incarceration. This article explores whether the mass incarceration of the past few decades impeded progress toward poverty reduction.…

  18. Engineering youth empowerment and poverty eradication through ...

    African Journals Online (AJOL)

    The much orchestrated fight to achieve poverty eradication and the economic empowerment of the youth appears to be pandering to the comical as the reality of the frustrations and anger of the youth over their poverty stricken plight stares the nation in the face. This is obvious considering the restiveness and massive ...

  19. Ninez y Pobreza (Childhood and Poverty).

    Science.gov (United States)

    Didonet, Vital

    1992-01-01

    Reviews data on child poverty worldwide, providing statistics on 20 poverty-related problems. Examines effects of economic factors (i.e., unemployment, wage stagnation, inflation, and internal migration) and political policies (i.e., military spending over health and education) on child well-being, arguing that families and children themselves…

  20. Violence, Grants, Poverty, Inequality, Unemployment and Hope ...

    African Journals Online (AJOL)

    Notwithstanding the impressive achievements recorded in poverty reduction, extraordinarily high levels of violent rebellion and strikes are encountered, unexpected after 20 years of democratic transition. This paper locates the drivers of this socio-political instability in poverty, inequality and unemployment: the consequence ...

  1. The History and Context of Rural Poverty.

    Science.gov (United States)

    Bedics, Bonnie

    1987-01-01

    Those who are poor and reside in the rural pockets of poverty are at a cumulative disadvantage in United States society. Low educational levels, poor health, lack of competitive job skills, and a mindset restricted by poverty give little hope for mobility--especially in communities devoid of opportunity and supportive services. (JHZ)

  2. Multidimensional poverty and child survival in India.

    Science.gov (United States)

    Mohanty, Sanjay K

    2011-01-01

    Though the concept of multidimensional poverty has been acknowledged cutting across the disciplines (among economists, public health professionals, development thinkers, social scientists, policy makers and international organizations) and included in the development agenda, its measurement and application are still limited. OBJECTIVES AND METHODOLOGY: Using unit data from the National Family and Health Survey 3, India, this paper measures poverty in multidimensional space and examine the linkages of multidimensional poverty with child survival. The multidimensional poverty is measured in the dimension of knowledge, health and wealth and the child survival is measured with respect to infant mortality and under-five mortality. Descriptive statistics, principal component analyses and the life table methods are used in the analyses. The estimates of multidimensional poverty are robust and the inter-state differentials are large. While infant mortality rate and under-five mortality rate are disproportionately higher among the abject poor compared to the non-poor, there are no significant differences in child survival among educationally, economically and health poor at the national level. State pattern in child survival among the education, economical and health poor are mixed. Use of multidimensional poverty measures help to identify abject poor who are unlikely to come out of poverty trap. The child survival is significantly lower among abject poor compared to moderate poor and non-poor. We urge to popularize the concept of multiple deprivations in research and program so as to reduce poverty and inequality in the population.

  3. Information and Communication Technology for Poverty Reduction

    Science.gov (United States)

    Sharama, Motilal

    2005-01-01

    It has been estimated that over 700 million of the world's poor live in Asia-Pacifiui region i.e., those who earn $1 or less a day. Nearly one of three Asians is poor. It is claimed by multilateral agencies that the incidence of poverty (proportion of people below the poverty line) is slightly declining. Others question this claim and argue that…

  4. Industrial Diversification, Employment and Rural Poverty Reduction ...

    African Journals Online (AJOL)

    This study compares the impact of industrial diversification on employment and rural poverty reduction in China and Nigeria. The fact that both countries have the same poverty background and socio economic history makes it proper for them to forge closer ties so as to learn, with particular attention as to why one has failed ...

  5. Alleviating Poverty Through Vocational Education: The Nigerian ...

    African Journals Online (AJOL)

    The paper concludes that well-articulated vocational education policy and programmes will assist in employment generations and poverty reduction in Nigeria. Keywords: Alleviating Poverty, Vocational Education, Nigerian Experience Journal of Technology and Education in Nigeria Vol. 10 (2) 2005: pp. 10-14 ...

  6. Poverty, Education and Work: Some Introductory Thoughts

    Science.gov (United States)

    Agostino, Ana

    2007-01-01

    The article argues that poverty must be understood within a human rights approach, moving beyond a narrow economic definition. Recognising the multidimensional character of poverty also leads to acknowledge that there are no universal answers. Solutions must be culturally determined and this poses one of the major challenges for adult education…

  7. Poverty Alleviation Programmes in Nigeria: Reflections on ...

    African Journals Online (AJOL)

    In it, we have argued that past poverty alleviation policies and programmes have been elitist and non-participatory, especially by the target population. In most cases the designs for poverty alleviations are characterized by improper conceptualization, grandiosity and lack of social justice even in implementation. Based on ...

  8. Poverty: Teaching Mathematics and Social Justice

    Science.gov (United States)

    McCoy, Leah P.

    2008-01-01

    This article presents three mathematics lessons in a social justice setting of learning about poverty. Student activities include budgeting, graphic data representation, and linear regression, all in the context of connecting, communicating, and reasoning about poverty. (Contains 1 table, 5 figures and 6 online resources.)

  9. Using Asset Poverty Measures to Understand Poverty Dynamics, Poverty Traps and Farmer Behavior in Sub-Saharan Africa: A Focus on Rural Ethiopia

    Science.gov (United States)

    Liverpool, Lenis Saweda

    2009-01-01

    Effective poverty reduction programs require careful measurement of poverty status. Commonly used consumption or income-based classifications of poverty aggregate together households that are persistently poor with those who are only in poverty due to passing conditions. They also classify as non-poor households that are at risk of falling into…

  10. Poverty and development thinking:synthesis or uneasy compromise?

    OpenAIRE

    David Hulme

    2013-01-01

    Abstract This paper examines how the concept of poverty has waxed and waned within development thought and how these fluctuations have shaped development policy and action towards, or away from, direct goals of poverty reduction or eradication. It provides an overview of poverty in social thought; examines the contestations over how poverty analysis is positioned in development theory; charts the conceptual contestations around poverty; presents a brief history of poverty in development thoug...

  11. Contact problem for a solid indenter and a viscoelastic half-space described by the spectrum of relaxation and retardation times

    Science.gov (United States)

    Stepanov, F. I.

    2018-04-01

    The mechanical properties of a material which is modeled by an exponential creep kernel characterized by a spectrum of relaxation and retardation times are studied. The research is carried out considering a contact problem for a solid indenter sliding over a viscoelastic half-space. The contact pressure, indentation depth of the indenter, and the deformation component of the friction coefficient are analyzed with respect to the case of half-space material modeled by single relaxation and retardation times.

  12. TOURISM AND POVERTY IN BADUNG REGENCY, BALI

    Directory of Open Access Journals (Sweden)

    I Made Patera

    2016-03-01

    Full Text Available Tourism and poverty’s phenomenon had already been known since the birth of human civilization. In the 1980s poverty became a serious concern of practitioners and scholars in various part of the world, including Indonesia. Poverty is not only understood in understanding as an abstract concept, but also as a reality of economic injustice and inability to meet basic human needs in some rich countries but also in many developing countries in the world. The problem of poverty is a fundamental and tourism is one of the many ways to solve this. The objective of this paper is to study the role of tourism to poverty alleviation including: 1 to analyze the influence of tourism development toward economic performance; 2 to analyze the effect of economic performance on poverty eradication; 3 to analyze the influence of tourism on poverty alleviation; 4 to formulate a strategy to increase tourism's role in poverty alleviation in Badung Regency. This study uses quantitative approach supported by secondary data and qualitative approach using primary data obtained through observation, in-depth interviews and focus group discussions. Research was conducted in South Badung Regency in the most developed tourism growth and considered the richest district among all regencies in Bali Regencies. Various attempts have been made to alleviate poverty, however have not been able to resolve poverty problems. The grand theory of this study refers to Neoliberalism Theory, supported by Social Democratic Theory and Empowerment Theory. Neoliberalism emphasizes that poverty as an individual problem and prosperity can only be achieved by achievement of economic growth through free market mechanism. According to Social Democratic Theory the emergence of poverty came from outside of the community itself. While the emphasis on the Empowerment Theory is in improving the ability of individual or communities to become indepedence on economic, social welfare and political right. Data

  13. An elastic plate model for interseismic deformation in subduction zones

    Science.gov (United States)

    Kanda, Ravi V. S.; Simons, Mark

    2010-03-01

    Geodetic observations of interseismic surface deformation in the vicinity of subduction zones are frequently interpreted using simple kinematic elastic dislocation models (EDM). In this theoretical study, we develop a kinematic EDM that simulates plate subduction over the interseismic period (the elastic subducting plate model (ESPM)) having only 2 more degrees of freedom than the well-established back slip model (BSM): an elastic plate thickness and the fraction of flexural stresses due to bending at the trench that are released continuously. Unlike the BSM, in which steady state deformation in both plates is assumed to be negligible, the ESPM includes deformation in the subducting and overriding plates (owing to plate thickness), while still preserving the correct sense of convergence velocity between the subducting and overriding plates, as well as zero net steady state vertical offset between the two plates when integrated over many seismic cycles. The ESPM links elastic plate flexure processes to interseismic deformation and helps clarify under what conditions the BSM is appropriate for fitting interseismic geodetic data at convergent margins. We show that the ESPM is identical to the BSM in the limiting case of zero plate thickness, thereby providing an alternative motivation for the BSM. The ESPM also provides a consistent convention for applying the BSM to any megathrust interface geometry. Even in the case of nonnegligible plate thickness, the deformation field predicted by the ESPM reduces to that of the BSM if stresses related to plate flexure at the trench are released either continuously and completely at shallow depths during the interseismic period or deep in the subduction zone (below ˜100 km). However, if at least a portion of these stresses are not continuously released in the shallow portion of the subduction zone (via seismic or aseismic events), then the predicted surface velocities of these two models can differ significantly at horizontal

  14. Deep electrical resistivity structure of Costa Rican Subduction Zone

    Science.gov (United States)

    Worzewski, T.; Jegen, M.; Brasse, H.; Taylor, W.

    2009-04-01

    The water content and its distribution play an important role in the subduction process. Water is released from the subducting slab in a series of metamorphic reactions and the hydration of the mantle wedge may trigger the onset of melting, weakening and changes in the dynamics and thermal structure of subduction zones. However, the amount of water carried into the subduction zone and its distribution are not well constrained by existing data and are subject of vigorous current research in SFB574 (Volatiles and Fluids in Subduction Zones: Climate Feedback and Trigger Mechanisms for Natural Disasters). We will show numerical modeling studies which are used to determine the resolution and sensitivity of the MT response to fluids in the crust and subducting slab under the special condition of a coastal setting. In 2007-2008 we conducted a long-period magnetotelluric investigations in northwestern Costa Rica on- and offshore, where the Cocos Plate subducts beneath the Carribean plate. Eleven marine magnetotelluric Stations newly developed and constructed by IFM-GEOMAR and University of Kiel were deployed on the 200 km long marine extension of the profile for several months. We will present the data and its processing, as well as our attempts to eliminate motion induced noise observed on some stations on the cliffy shelf due to tidal waves hitting the shelf and trench parallel- and perpendicular currents. The marine profile was extended landwards by the Free University of Berlin over length of 160 kilometers with further 18 stations. We present preliminary modeling results of land data, which revealed interesting features, inter alia a possible image of fluid release from the downgoing slab in the forearc, as well as ongoing modeling of the combined on- and offshore data sets.

  15. Subduction bottom-to-top: The northeast Caribbean

    Science.gov (United States)

    Ten Brink, U. S.

    2017-12-01

    The Northeast Caribbean provides a prime example for the surficial expression of deep subduction processes and their combined effect on natural hazard. The subducting North American slab, recognized in tomography to depths of hundreds of kilometers, has been moving primarily westward at 2 cm/yr relative to the overlying Caribbean plate throughout most of the Cenozoic. A proposed tear in the slab northeast of Puerto Rico, separating a steeply-dipping slab to the west from less-steep slab to the east, is likely responsible for deep (century thrust earthquakes (e.g., in 1946) demonstrate seismic subduction, the trench there is shallow, and strain partitioning is expressed as strike-slip earthquakes onshore (e.g., Haiti in 2010). Slab geometry of the transition between these two subducting segments is unclear, as are the surficial effects of the westward "plowing" of the North American slab through the Caribbean mantle. East and south of the inferred tear, subduction accompanied by volcanism is taking place off the northern Lesser Antilles. Tectonic variability of subduction in the northeast Caribbean is likely responsible for faulting within the overlying plate that have generated large earthquakes and tsunamis in 1867 in the Virgin Islands, and in 1918 off the west coast of Puerto Rico. This variability, however, may limit to a few hundred kilometers, the maximum rupture length along the subduction zone. Extreme-wave deposits at Anegada, British Virgin Islands, may represent a large thrust earthquake east of the tear or a smaller normal earthquake on the trench outer wall. The deep trench likely shields Puerto Rico from tsunamis of remote origin, as shown during the 1755 Lisbon tsunami.

  16. Movements out of poverty among elderly widows.

    Science.gov (United States)

    Dodge, H H

    1995-07-01

    Elderly widows are disproportionately in poverty in the United States. However, past research has also shown that a significant number of poor elderly widows do move out of poverty. This work addresses two questions: What are the characteristics of elderly widows who exited from poverty, and what is the magnitude of the increase in income at the time of exit? An event history approach was taken using monthly data from the Survey of Income and Program Participation. Some of the findings are: living with family members is a strong predictor for the transition out of poverty among poor elderly women; those who are permanently impoverished tend to rely solely on food stamps and SSI; elderly widows from poverty with relatively large increases in income; those who exited due to an increase in pension income or gifts had increased their income significantly more than those who exited through other sources.

  17. Comparison of the aerodynamics of bridge cables with helical fillets and a pattern-indented surface

    DEFF Research Database (Denmark)

    Kleissl, K.; Georgakis, C.T.

    2012-01-01

    In this paper, the aerodynamics of bridge cables with helical fillets and a pattern-indented surface are examined. To this end, an extensive wind-tunnel test campaign was undertaken to measure the static force coefficients about the critical Reynolds number region, with varying relative cable...... cable was found to have a much slower flow transition for near normal flow and relatively large lift force components for the yawed positions. Flow visualizations confirmed the existence of specific flow structures which are often associated with the presence of lower drag or large lift forces...

  18. On the use of Raman spectroscopy and instrumented indentation for characterizing damage in machined carbide ceramics

    Science.gov (United States)

    Groth, Benjamin Peter

    Machining is a necessary post-processing step in the manufacturing of many ceramic materials. Parts are machined to meet specific dimensions, with tight tolerances, not attainable from forming alone, as well as to achieve a desired surface finish. However, the machining process is very harsh, often employing the use of high temperatures and pressures to achieve the wanted result. In the case of silicon carbide, a material with extremely high hardness and stiffness, machining is very difficult and requires machining conditions that are highly aggressive. This can leave behind residual stresses in the surface of the material, cause unwanted phase transformations, and produce sub-surface deformation that can lead to failure. This thesis seeks to determine the effect of various machining conditions on the Raman spectra and elastic properties of sintered silicon carbide materials. Sample sets examined included hot-pressed silicon carbide tiles with four different surface finishes, as well as "ideal" single crystal silicon carbide wafers. The surface finishes studied were as follows: an as-pressed finish; a grit blast finish; a harsh rotary ground finish; and a mirror polish. Each finish imparts a different amount, as well as type, of deformation to the sample and are each utilized for a specific application. The sample surfaces were evaluated using a combination of Raman spectroscopy, for phase identification and stress analysis, and nanoindentation, for obtaining elastic properties and imparting uniform controlled deformation to the samples. Raman spectroscopy was performed over each sample surface using 514- and 633-nm wavelength excitation, along with confocal and non-confocal settings to study depth variation. Surfaces stresses were determined using peak shift information extracted from Raman spectra maps, while other spectral variations were used to compare levels of machining damage. Elastic modulus, hardness, and plastic work of indentation maps were generated

  19. Chirality and grain boundary effects on indentation mechanical properties of graphene coated on nickel foil.

    Science.gov (United States)

    Yan, Yuping; Lv, Jiajiang; Liu, Sheng

    2018-04-20

    We investigate chirality and grain boundary (GB) effects on indentation mechanical properties of graphene coated on nickel foil using molecular dynamics simulations. The models of graphene with different chirality angles, different numbers of layers and tilt GBs were established. It was found that the chirality angle of few-layer graphene had a significant effect on the load bearing capacity of graphene/nickel systems, and this turns out to be more significant when the number of layers is greater than one. The enhancement to the contact stiffness, elastic capacity and the load bearing capacity of graphene with tilt GBs was lower than that of pristine graphene.

  20. Indentation in the Right Ventricle by an Incomplete Pericardium on 3-Dimensional Reconstructed Computed Tomography

    Directory of Open Access Journals (Sweden)

    Hak Ju Kim

    2017-08-01

    Full Text Available We report the case of a 17-year-old girl who presented with an indentation in the right ventricle caused by an incomplete pericardium on preoperative 3-dimensional reconstructed computed tomography. She was to undergo surgery for a partial atrioventricular septal defect and secundum atrial septal defect. Preoperative electrocardiography revealed occasional premature ventricular beats. We found the absence of the left side of the pericardium intraoperatively, and this absence caused strangulation of the diaphragmatic surface of the right ventricle. After correcting the lesion, the patient’s rhythm disturbances improved.

  1. Dislocation sources and slip band nucleation from indents on silicon wafers

    International Nuclear Information System (INIS)

    Wittge, J.; Danilewsky, A.N.; Allen, D.

    2010-01-01

    The nucleation of dislocations at controlled indents in silicon during rapid thermal annealing has been studied by in situ X-ray diffraction imaging (topography). Concentric loops extending over pairs of inclined {111} planes were formed, the velocities of the inclined and parallel segments being almost equal. Following loss of the screw segment from the wafer, the velocity of the inclined segments almost doubled, owing to removal of the line tension of the screw segments. The loops acted as obstacles to slip band propagation. (orig.)

  2. Chirality and grain boundary effects on indentation mechanical properties of graphene coated on nickel foil

    Science.gov (United States)

    Yan, Yuping; Lv, Jiajiang; Liu, Sheng

    2018-04-01

    We investigate chirality and grain boundary (GB) effects on indentation mechanical properties of graphene coated on nickel foil using molecular dynamics simulations. The models of graphene with different chirality angles, different numbers of layers and tilt GBs were established. It was found that the chirality angle of few-layer graphene had a significant effect on the load bearing capacity of graphene/nickel systems, and this turns out to be more significant when the number of layers is greater than one. The enhancement to the contact stiffness, elastic capacity and the load bearing capacity of graphene with tilt GBs was lower than that of pristine graphene.

  3. Mechanical properties of bovine cortical bone based on the automated ball indentation technique and graphics processing method.

    Science.gov (United States)

    Zhang, Airong; Zhang, Song; Bian, Cuirong

    2018-02-01

    Cortical bone provides the main form of support in humans and other vertebrates against various forces. Thus, capturing its mechanical properties is important. In this study, the mechanical properties of cortical bone were investigated by using automated ball indentation and graphics processing at both the macroscopic and microstructural levels under dry conditions. First, all polished samples were photographed under a metallographic microscope, and the area ratio of the circumferential lamellae and osteons was calculated through the graphics processing method. Second, fully-computer-controlled automated ball indentation (ABI) tests were performed to explore the micro-mechanical properties of the cortical bone at room temperature and a constant indenter speed. The indentation defects were examined with a scanning electron microscope. Finally, the macroscopic mechanical properties of the cortical bone were estimated with the graphics processing method and mixture rule. Combining ABI and graphics processing proved to be an effective tool to obtaining the mechanical properties of the cortical bone, and the indenter size had a significant effect on the measurement. The methods presented in this paper provide an innovative approach to acquiring the macroscopic mechanical properties of cortical bone in a nondestructive manner. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Continuous FEM simulation of the nanoindentation. Actual indenter tip geometries, material elastoplastic deformation laws and universal hardness

    Energy Technology Data Exchange (ETDEWEB)

    Bouzakis, K.D.; Michailidis, N.; Hadjiyiannis, S.; Skordaris, G. [Mechanical Engineering Dept., Aristoteles Univ. of Thessaloniki (Greece); Erkens, G. [CemeCon AG, Wuerselen (Germany)

    2002-09-01

    The precise knowledge of materials mechanical properties is always a core issue in every technical application. Through a developed finite elements method (FEM) continuous simulation of the nanoindentation, the applied force course versus the penetration depth is adequately simulated during the loading and unloading phases of this test, and the corresponding material stress-strain curves, as well as the universal hardness, are stepwise defined. Furthermore, the actual tip geometries of various indenters are approached and through equivalent magnitudes described. The results show that the defined material elastoplastic deformation characteristics are independent of the indenter type, as Vickers or Berkovich, since the existing indenter tip form deviations from their ideal geometry are considered. Furthermore, using the developed FEM-based nanoindentation simulation, the influence of the indenter tip geometry on the defined constitutive laws and the universal hardness is sufficiently elucidated. Various materials stress-strain curves and universal hardness courses versus the indentation depth, determined by means of the developed procedure, are presented. (orig.)

  5. THE APPLICATION OF AN ENDOGENOUS POVERTY LINE AND ITS RELATIONSHIP WITH THE POVERTY IMPACT OF ECONOMIC SHOCKS: AN EMPIRICAL INVESTIGATION

    OpenAIRE

    TEGUH DARTANTO

    2013-01-01

    Most of the studies on the poverty impact of economic shocks as well as policy reforms assumed the poverty line as a fixed line; thus, the poverty outcome of shocks may underestimate (overestimate) and mislead in policy guidance. This research aims at empirically investigating the difference of poverty outcome between applying a fixed and an endogenous poverty line. Applying computable general equilibrium microsimulation (CGE-MS), this study has empirically proven that, if a fixed poverty lin...

  6. Relating seismic observables to fluid migration in subduction zones

    Science.gov (United States)

    Abers, G. A.; Fischer, K. M.; Hirth, G.; Holtzman, B. K.; Plank, T.; Wiens, D. A.

    2011-12-01

    Seismic images provide quantitative information about the physical state of the mantle. In subduction zones, a number of recent high-density broadband seismic field experiments provide images and analyses of the down-dip changes to the slab surface, the subarc melting region of the mantle, and the cold forearc nose. However, the implications of the measured quantities (P and S velocities Vp and Vs, attenuation Qp and Qs, and measures of seismic anisotropy) for the quantities of geodynamic interest (such as temperature, melt, water content, and composition) are not unique. We are embarking on an effort to systematically improve our understanding of the interrelationships between seismic and geodynamic parameters, leveraging seismic data collected from dense arrays in several subduction zones. These data compare well with arc chemistry, revealing complementary patterns between chemistry and seismology along strike in Central America and down dip in the Marianas. The slab surface can be imaged through a variety of reflections and mode conversions, including receiver functions. These show a variety of characteristics at different depths. Many subduction zones exhibit a transition from high amplitude conversions at the shallow thrust zone, indicating a weak and probably over-pressured subduction channel, to a deeper region that can be characterized by subducting uneclogitized crust. Elsewhere and deeper, the effects of steep thermal gradients become more significant in seismic images. Lower than expected velocities within the slab suggest the presence of partly (10-20%) serpentinized subducting mantle, at least offshore Nicaragua, but that remains to be shown in most subduction zones. In the wedge, low seismic velocities and high shear attenuation (1/Qs) indicate elevated temperatures, consistent with those recorded in the compositions of arc basalts. In some subduction zones seismic velocities (e.g., Vp/Vs) may indicate the presence of melt or high water content

  7. Poverty, Policy and Price Transmission

    DEFF Research Database (Denmark)

    Elleby, Christian

    This thesis consists of four self-contained chapters in which different aspects of the relationship between international commodity markets and domestic food markets are explored. What motivates the analysis is the recent surge in international commodity prices and the controversy over the poverty...... of the real food price process based on which dynamic forecasts and historical decompositions are calculated. Results indicate that, despite the low degree of pass-through from international to domestic rice prices, food prices in general grew as fast as expected or faster, given the surge...... impact of the 2007-8 ‘food crisis’, in particular. The first paper analyses, in a stylized economic model, how the response of domestic aggregate food prices to an international shock depends on features of the country’s income distribution. The model is based on a dichotomy between traded and purely...

  8. Poverty, Policy and Price Transmission

    DEFF Research Database (Denmark)

    Elleby, Christian

    This thesis consists of four self-contained chapters in which different aspects of the relationship between international commodity markets and domestic food markets are explored. What motivates the analysis is the recent surge in international commodity prices and the controversy over the poverty...... domestic goods. Households prefer the traded good which they substitute towards as their incomes increase, thus exposing themselves to world market price swings. Price transmission from international to domestic markets therefore increases with per capita income but also with income inequality. Model...... impact of the 2007-8 ‘food crisis’, in particular. The first paper analyses, in a stylized economic model, how the response of domestic aggregate food prices to an international shock depends on features of the country’s income distribution. The model is based on a dichotomy between traded and purely...

  9. Poverty of the stimulus revisited.

    Science.gov (United States)

    Berwick, Robert C; Pietroski, Paul; Yankama, Beracah; Chomsky, Noam

    2011-01-01

    A central goal of modern generative grammar has been to discover invariant properties of human languages that reflect "the innate schematism of mind that is applied to the data of experience" and that "might reasonably be attributed to the organism itself as its contribution to the task of the acquisition of knowledge" (Chomsky, 1971). Candidates for such invariances include the structure dependence of grammatical rules, and in particular, certain constraints on question formation. Various "poverty of stimulus" (POS) arguments suggest that these invariances reflect an innate human endowment, as opposed to common experience: Such experience warrants selection of the grammars acquired only if humans assume, a priori, that selectable grammars respect substantive constraints. Recently, several researchers have tried to rebut these POS arguments. In response, we illustrate why POS arguments remain an important source of support for appeal to a priori structure-dependent constraints on the grammars that humans naturally acquire. Copyright © 2011 Cognitive Science Society, Inc.

  10. Highly oxidising fluids generated during serpentinite breakdown in subduction zones.

    Science.gov (United States)

    Debret, B; Sverjensky, D A

    2017-09-04

    Subduction zones facilitate chemical exchanges between Earth's deep interior and volcanism that affects habitability of the surface environment. Lavas erupted at subduction zones are oxidized and release volatile species. These features may reflect a modification of the oxidation state of the sub-arc mantle by hydrous, oxidizing sulfate and/or carbonate-bearing fluids derived from subducting slabs. But the reason that the fluids are oxidizing has been unclear. Here we use theoretical chemical mass transfer calculations to predict the redox state of fluids generated during serpentinite dehydration. Specifically, the breakdown of antigorite to olivine, enstatite, and chlorite generates fluids with high oxygen fugacities, close to the hematite-magnetite buffer, that can contain significant amounts of sulfate. The migration of these fluids from the slab to the mantle wedge could therefore provide the oxidized source for the genesis of primary arc magmas that release gases to the atmosphere during volcanism. Our results also show that the evolution of oxygen fugacity in serpentinite during subduction is sensitive to the amount of sulfides and potentially metal alloys in bulk rock, possibly producing redox heterogeneities in subducting slabs.

  11. Terrain accretion along the subduction interface: numerical modeling

    Science.gov (United States)

    Vogt, K.; Gerya, T.

    2012-04-01

    The oceanic floor contains allochthonous terranes (extinct ridges and arcs, continental fragments and volcanic piles) that move with the oceanic crust and may collide with continental margins to form collisional orogens that are believed to have contributed to the growth of the continental crust. The dynamics of terrane accretion and its implcation in relation to crustal growth were analyzed using a thermomechanical-pertological numerical model of an oceanic-continental subduction zone. The model is based on the i2vis code, that solves the govering equations of mass, momentum and energy for a viscous-plastic rheology. Our results indicate that allochthonous terranes may subduct or accrete depending on their rheological strength and the negative buoyancy of the downgoing slab, which is imposed by its thermal structure. Subduction of cold and dense oceanic lithosphere coupled with the collsion of rheologically strong terranes results in deep subdution. Crustal material may be subducted back into the mantle or be incorporated into active arcs that form above the overriding plate. Terranes with a weak crustal structure that are embedded in young oceanic lithosphere are less prone to subdution and may be accreted in form of collisional orogens and accreted terranes. Weak crustal material is scrapped off the downgoing plate and added to the continental margin, which leads to rapid growth of the continental crust and may result in plate failure associated with slab break off. In cases where slab break off occurs a new subduction zone is formed behnind the accreted terrane.

  12. A model for the termination of the Ryukyu subduction zone against Taiwan: A junction of collision, subduction/separation, and subduction boundaries

    Science.gov (United States)

    Wu, F.T.; Liang, W.-T.; Lee, J.-C.; Benz, H.; Villasenor, A.

    2009-01-01

    The NW moving Philippine Sea plate (PSP) collides with the Eurasian plate (EUP) in the vicinity of Taiwan, and at the same time, it subducts toward the north along SW Ryukyu. The Ryukyu subduction zone terminates against eastern Taiwan. While the Ryukyu Trench is a linear bathym??trie low about 100 km east of Taiwan, closer to Taiwan, it cannot be clearly identified bathymetrically owing to the deformation related to the collision, making the location of the intersection of the Ryukyu with Taiwan difficult to decipher. We propose a model for this complex of boundaries on the basis of seismicity and 3-D velocity structures. In this model the intersection is placed at the latitude of about 23.7??N, placing the northern part of the Coastal Range on EUP. As PSP gets deeper along the subduction zone it collides with EUP on the Taiwan side only where they are in direct contact. Thus, the Eurasian plate on the Taiwan side is being pushed and compressed by the NW moving Philippine Sea plate, at increasing depth toward the north. Offshore of northeastern Taiwan the wedge-shaped EUP on top of the Ryukyu subducting plate is connected to the EUP on the Ryukyu side and coupled to the NW moving PSP by friction at the plate interface. The two sides of the EUP above the western end of the subduction zone are not subjected to the same forces, and a difference in motions can be expected. The deformation of Taiwan as revealed by continuous GPS measurements, geodetic movement along the east coast of Taiwan, and the formation of the Hoping Basin can be understood in terms of the proposed model. Copyright 2009 by the American Geophysical Union.

  13. Sub-micron indent induced plastic deformation in copper and irradiated steel; Deformation plastique induite par l'essai d'indentation submicronique, dans le cuivre et l'acier 316L irradie

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Ch

    1999-07-01

    In this work we aim to study the indent induced plastic deformation. For this purpose, we have developed a new approach, whereby the indentation curves provides the mechanical behaviour, while the deformation mechanisms are observed thanks to Transmission Electron Microscopy (TEM). In order to better understand how an indent induced dislocation microstructure forms, numerical modeling of the indentation process at the scale of discrete dislocations has been worked out as well. Validation of this modeling has been performed through direct comparison of the computed microstructures with TEM micrographs of actual indents in pure Cu (001]. Irradiation induced modifications of mechanical behaviour of ion irradiated 316L have been investigated, thanks to the mentioned approach. An important hardening effect was reported from indentation data (about 50%), on helium irradiated 316L steel. TEM observations of the damage zone clearly show that this behaviour is associated with the presence of He bubbles. TEM observations of the indent induced plastic zone also showed that the extent of the plastic zone is strongly correlated with hardness, that is to say: harder materials gets a smaller plastic zone. These results thus clearly established that the selected procedure can reveal any irradiation induced hardening in sub-micron thick ion irradiated layers. The behaviour of krypton irradiated 316L steel is somewhat more puzzling. In one hand indeed, a strong correlation between the defect cluster size and densities on the irradiation temperature is observed in the 350 deg. C - 600 deg. C range, thanks to TEM observations of the damage zone. On the other hand, irradiation induced hardening reported from indentation data is relatively small (about 10%) and shows no dependence upon the irradiation temperature (within the mentioned range). In addition, it has been shown that the reported hardening vanishes following appropriate post-irradiation annealing, although most of the TEM

  14. Water and Poverty in Two Colombian Watersheds

    Directory of Open Access Journals (Sweden)

    Nancy Johnson

    2009-02-01

    Full Text Available Watersheds, especially in the developing world, are increasingly being managed for both environmental conservation and poverty alleviation. How complementary are these objectives? In the context of a watershed, the actual and potential linkages between land and water management and poverty are complex and likely to be very site specific and scale dependent. This study analyses the importance of watershed resources in the livelihoods of the poor in two watersheds in the Colombian Andes. Results of the participatory poverty assessment reveal significant decreases in poverty in both watersheds over the past 25 years, which was largely achieved by the diversification of livelihoods outside of agriculture. Water is an important resource for household welfare. However, opportunities for reducing poverty by increasing the quantity or quality of water available to the poor may be limited. While improved watershed management may have limited direct benefits in terms of poverty alleviation, there are important indirect linkages between watershed management and poverty, mainly through labour and service markets. The results suggest that at the level of the watershed the interests of the rich and the poor are not always in conflict over water. Sectoral as well as socio-economic differences define stakeholder groups in watershed management. The findings have implications for policymakers, planners and practitioners in various sectors involved in the implementation of integrated water resources management (IWRM.

  15. Finite Element Analysis of Aluminum Honeycombs Subjected to Dynamic Indentation and Compression Loads

    Directory of Open Access Journals (Sweden)

    A.S.M. Ayman Ashab

    2016-03-01

    Full Text Available The mechanical behavior of aluminum hexagonal honeycombs subjected to out-of-plane dynamic indentation and compression loads has been investigated numerically using ANSYS/LS-DYNA in this paper. The finite element (FE models have been verified by previous experimental results in terms of deformation pattern, stress-strain curve, and energy dissipation. The verified FE models have then been used in comprehensive numerical analysis of different aluminum honeycombs. Plateau stress, σpl, and dissipated energy (EI for indentation and EC for compression have been calculated at different strain rates ranging from 102 to 104 s−1. The effects of strain rate and t/l ratio on the plateau stress, dissipated energy, and tearing energy have been discussed. An empirical formula is proposed to describe the relationship between the tearing energy per unit fracture area, relative density, and strain rate for honeycombs. Moreover, it has been found that a generic formula can be used to describe the relationship between tearing energy per unit fracture area and relative density for both aluminum honeycombs and foams.

  16. Static Indentation Load Capacity of the Superelastic 60NiTi for Rolling Element Bearings

    Science.gov (United States)

    DellaCorte, Christopher; Moore, Lewis E., III; Clifton, Joshua S.

    2012-01-01

    The nickel-rich, binary nickel-titanium alloys, such as 60NiTi (60Ni-40Ti by wt%), are emerging as viable materials for use in mechanical components like rolling element bearings and gears. 60NiTi is a superelastic material that simultaneously exhibits high hardness and a relatively low elastic modulus (approx.100 GPa). These properties result in the potential to endure extremely high indentation loads such as those encountered in bearings, gears and other mechanical components. In such applications, quantifying the load that results in permanent deformation that can affect component performance and life is important. In this paper, the static load capacity is measured by conducting indentation experiments in which 12.7 mm diameter balls made from the ceramic Si3N4 are pressed into highly polished, hardened 60NiTi flat plates. Hertz stress calculations are used to estimate contact stress. The results show that the 60NiTi surface can withstand an approximately 3400 kN load before significant denting (>0.6 microns deep) occurs. This load capacity is approximately twice that of high performance bearing steels suggesting that the potential exists to make highly resilient bearings and components from such materials.

  17. Depth-sensing nano-indentation on a myelinated axon at various stages

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wei-Chin; Liao, Jiunn-Der [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Lin, Chou-Ching K [Department of Neurology, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Ju, Ming-Shaung, E-mail: jdliao@mail.ncku.edu.tw [Department of Mechanical Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2011-07-08

    A nano-mechanical characterization of a multi-layered myelin sheath structure, which enfolds an axon and plays a critical role in the transmission of nerve impulses, is conducted. Schwann cells co-cultured in vitro with PC12 cells for various co-culture times are differentiated to form a myelinated axon, which is then observed using a transmission electron microscope. Three major myelination stages, with distinct structural characteristics and thicknesses around the axon, can be produced by varying the co-culture time. A dynamic contact module and continuous depth-sensing nano-indentation are used on the myelinated structure to obtain the load-on-sample versus measured displacement curve of a multi-layered myelin sheath, which is used to determine the work required for the nano-indentation tip to penetrate the myelin sheath. By analyzing the harmonic contact stiffness versus the measured displacement profile, the results can be used to estimate the three stages of the multi-layered structure on a myelinated axon. The method can also be used to evaluate the development stages of myelination or demyelination during nerve regeneration.

  18. Effect of processing on fracture toughness of silicon carbide as determined by Vickers indentations

    Science.gov (United States)

    Dannels, Christine M.; Dutta, Sunil

    1989-01-01

    Several alpha-SiC materials were processed by hot isostatic pressing (HIPing) and by sintering an alpha-SiC powder containing boron and carbon. Several beta-SiC materials were processed by HIPing a beta-SiC powder with boron and carbon additions. The fracture toughnesses K(sub 1c) of these beta- and alpha-SiC materials were estimated from measurements of Vickers indentations. The three formulas used to estimate K(sub 1c) from the indentation fracture patterns resulted in three ranges of K(sub 1c) estimates. Furthermore, each formula measured the effects of processing differently. All three estimates indicated that fine-grained HIPed alpha-SiC has a higher K(sub 1c) than coarsed-grained sintered alpha-SiC. Hot isostatically pressed beta-SiC, which had an ultrafine grain structure, exhibited a K(sub 1c) comparable to that of HIPed alpha-SiC.

  19. A study on the evaluation of material degradation using ball indentation method

    International Nuclear Information System (INIS)

    Kim, Jeong Pyo; Seok, Chang Sung; Ahn, Ha Neul

    2000-01-01

    As huge energy transfer systems like a nuclear power plant, steam power plant and petrochemical plant are operated for a long time, mechanical properties are changed by degradation. The life time of the systems can be affected by the mechanical properties. BI(Ball Indentation) test has a potential to replace conventional fracture tests like a uniaxial tensile test, fracture toughness test, hardness test and so on. In this paper, we would like to present the aging evaluation technique by the BI method. The four classes of the thermally aged 1Cr-1Mo-0.25V specimens were prepared using an artificially accelerated aging method. Tensile tests, fracture toughness tests, hardness tests and BI tests were performed. The results of the BI tests were in good agreement with fracture characteristics by a standard fracture test method. The IDE(Indentation Deformation Energy) of a BI technique as a new parameter for evaluating a degradation was suggested and the new IDE parameter clearly depicts the degradation degree

  20. Experimental creep behavior of porcine liver under indentation with laparoscopic grasper for MIS applications

    Directory of Open Access Journals (Sweden)

    Cheng-mo Cai

    2017-06-01

    Full Text Available Mechanical response of soft tissues behaved disparate due to fast and large deformation during surgical grasping, so there is a need for experimental databases of biomechanical characteristics of soft tissue under the contact of MIS tool, which are more useful for designing new surgical instruments, training inexperienced surgeons, improving surgical simulations and developing surgical robotics system. A novel indentation test to simulate the real-time surgical operation condition was present in this paper. The creep behavior of porcine liver in vitro was studied under uniaxial indentation by using MIS grasper. The nominal stress between the grasper and the liver was 0.02 to 0.1 MPa, the loading velocity was 1 to 3 mm/s, and the holding time was 300 s to simulate clamping tissue operation. Results showed that the creep process of the liver during 300 s of duration can be divided into three stages: loading stage I, transition creep stage II and steady creep stage III. The creep characteristic of liver behaves time-dependent, load-dependent and strongly loading velocity-dependent due to its nonlinear viscoelastic characteristics and hysteresis characteristics. These creep behavior might also be associated with the deformation, migration and biochemical reaction of the liver cells. The phenomenological model derived in this paper may describe the creep behavior of the liver. The results would provide experimental databases and phenomenological models for investigating biomechanical characteristics of soft tissue under the contact of MIS tool.