10,394 research outputs found
Damage as Gamma-limit of microfractures in anti-plane linearized elasticity
A homogenization result is given for a material having brittle inclusions arranged in a periodic structure.
<br/>
According to the relation between the softness parameter and the size of the microstructure, three different limit models are deduced via Gamma-convergence.
<br/>
In particular, damage is obtained as limit of periodically distributed
microfractures
B2 and G2 Toda systems on compact surfaces: a variational approach
We consider the B2 and G2 Toda systems on compact surfaces. We attack the
problem using variational techniques. We get existence and multiplicity of
solutions under a topological assumption on the surface and some generic
conditions on the parameters. We also extend some of the results to the case of
general systems.Comment: 28 pages, accepted on Journal of Mathematical Physic
Transforming nonlocality into frequency dependence: a shortcut to spectroscopy
Measurable spectra are theoretically very often derived from complicated
many-body Green's functions. In this way, one calculates much more information
than actually needed. Here we present an in principle exact approach to
construct effective potentials and kernels for the direct calculation of
electronic spectra. In particular, the potential that yields the spectral
function needed to describe photoemission turns out to be dynamical but {\it
local} and {\it real}. As example we illustrate this ``photoemission
potential'' for sodium and aluminium, modelled as homogeneous electron gas, and
discuss in particular its frequency dependence stemming from the nonlocality of
the corresponding self-energy. We also show that our approach leads to a very
short derivation of a kernel that is known to well describe absorption and
energy-loss spectra of a wide range of materials
Simulating the formation of a proto-cluster at z~2
We present results from two high-resolution hydrodynamical simulations of
proto-cluster regions at z~2.1. The simulations have been compared to
observational results for the socalled Spiderweb galaxy system, the core of a
putative proto-cluster region at z = 2.16, found around a radio galaxy. The
simulated regions have been chosen so as to form a poor cluster with M200~10^14
h-1 Msun (C1) and a rich cluster with M200~2x10^15 h-1 Msun (C2) at z = 0. The
simulated proto-clusters show evidence of ongoing assembly of a dominating
central galaxy. The stellar mass of the brightest cluster galaxy (BCG) of the
C2 system is in excess with respect to observational estimates for the
Spiderweb galaxy, with a total star formation rate which is also larger than
indicated by observations. We find that the projected velocities of galaxies in
the C2 cluster are consistent with observations, while those measured for the
poorer cluster C1 are too low compared to the observed velocities. We argue
that the Spiderweb complex resemble the high-redshift progenitor of a rich
galaxy cluster. Our results indicate that the included supernovae feedback is
not enough to suppress star formation in these systems, supporting the need of
introducing AGN feedback. According to our simulations, a diffuse atmosphere of
hot gas in hydrostatic equilibrium should already be present at this redshift,
and enriched at a level comparable to that of nearby galaxy clusters. The
presence of this gas should be detectable with future deep X-ray observations.Comment: 6 pages, 4 figures, accepted for publication in MNRAS (Letters
E-ABR in patients with cochlear implant: A comparison between patients with malformed cochlea and normal cochlea
OBJECTIVES: This study aims to compare the electrical auditory brainstem response (EABR) following cochlear implant (CI) surgery in pediatric subjects with cochlear malformation and a normal cochlea, in order to assess the sensitivity of EABR and to evaluate the surgery outcome. MATERIALS and METHODS: A total of 26 pediatric subjects who were deaf and scheduled for CI surgery were enrolled into this case control study. Group A (n=20) included subjects with a normo-conformed cochlea. Group B (n=6) included subjects with cochlear malformation. Subjects were evaluated with EABR immediately (T0) and 6 months (T1) post-CI surgery. The EABR Waves III and V average amplitude and latency were compared across time, separately for each group, and across groups, separately for each time. RESULTS: Auditory brainstem response (ABR) could only be recorded in Group A. We were able to record EABR from all subjects at T0 and T1, and waves III and V were present in all the recorded signals. There were no statistically significant differences between T0 and T1 in EABR Waves III and V in terms of average amplitude and latency in neither group. When comparing Groups A and B, the only statistically significant difference was the average amplitude of wave V, both at T0 and T1. CONCLUSION: EABR is a valid tool to measure the auditory nerve integrity after CI surgery in patients with a normal and malformed cochlea, as shown by its ability to measure waves III and V when ABR is absent. The EABR testing should be performed before and after CI surgery, and EABR should be used as a measure of outcome, especially in patients with a malformed cochlea
Sifat-sifat Isomorfisma Graf Fuzzy Pada Graf Fuzzy Kuat
Fuzzy graph is a graph consists pairs of vertex and edge that have degree of membership containing closed interval of real number [0,1] on each edge and vertex. A fuzzy graph is said to be a strong fuzzy graph if degree of membership edge with the same minimum degree of membership vertex and degree of membership vertex for each edge with . In this paper describes the properties of fuzzy graphs isomorphism include weak isomorphism, co-weak isomorphism, and isomorphism on strong fuzzy graph
Approximations for many-body Green's functions: insights from the fundamental equations
Several widely used methods for the calculation of band structures and photo
emission spectra, such as the GW approximation, rely on Many-Body Perturbation
Theory. They can be obtained by iterating a set of functional differential
equations relating the one-particle Green's function to its functional
derivative with respect to an external perturbing potential. In the present
work we apply a linear response expansion in order to obtain insights in
various approximations for Green's functions calculations. The expansion leads
to an effective screening, while keeping the effects of the interaction to all
orders. In order to study various aspects of the resulting equations we
discretize them, and retain only one point in space, spin, and time for all
variables. Within this one-point model we obtain an explicit solution for the
Green's function, which allows us to explore the structure of the general
family of solutions, and to determine the specific solution that corresponds to
the physical one. Moreover we analyze the performances of established
approaches like over the whole range of interaction strength, and we
explore alternative approximations. Finally we link certain approximations for
the exact solution to the corresponding manipulations for the differential
equation which produce them. This link is crucial in view of a generalization
of our findings to the real (multidimensional functional) case where only the
differential equation is known.Comment: 17 pages, 7 figure
Like grandparents, like parents: Empirical evidence and psychoanalytic thinking on the transmission of parenting styles
The authors discuss the issue of intergenerational transmission of parenting from an empirical and psychoanalytic perspective. After presenting a framework to explain their conception of parenting, they describe intergenerational transmission of parenting as a key to interpreting and eventually changing parenting behaviors. Then they present (1) the empirical approach aimed at determining if there is actually a stability across generations that contributes to harsh parenting and eventually maltreatment and (2) the psyphoanalytic thinking that seeks to explain the continuity in terms of representations and clinical phenomena. The authors also discuss the relationship between the attachment and the caregiving systems and hypothesize a common base for the two systems in childhood experience. Finally, they propose the psychoanalytic perspective as a fruitful theoretical framework to integrate the evidence for the neurophysiological mediators and moderators of intergenerational transmission. Psychoanalytically informed research can provide clinically relevant insights and hypotheses to be tested
Pengaruh Arus Kas Aktivitas Operasi terhadap Tingkat Likuiditas
The purpose of this research is to analyze the growth of the operating cash flow and the level of liquidity at PT Sarana Menara Nusantara Tbk , and also to the influence of operating cash flow to liquidity at PT Sarana Menara Nusantara Tbk. The research method using descriptive method and technique of statistics are Correlation, The coefficient of Determination, Linier Regression Analysis and Hypothesis Test, which helped by SPSS 22.00 for Windows program. The research results are 1) The growth rate of the cash flow operating activities always increase every year. 2) The growth rate of the level of liquidity at PT Sarana Menara Nusantara Tbk is fluctuating every year. 3) Operating cash flow give no significant effect on the level of liquidity, the effect is only 51,84%.
Keywords: cash, cash flow, operating activities, liquidit
- …