2,958 research outputs found
Determination of oscillator strength of confined excitons in a semiconductor microcavity
We have achieved a significant experimental Rabi-splitting (3.4 meV) for
confined polaritons in a planar semiconductor microcavity for only a
single quantum well (SQW) of GaAs (10 nm) placed at the antinode. The
Rabi-splitting phenomena are discussed in detail based on the semiclassical
theory, where two coupled harmonic oscillators (excitons and photons) are used
to describe the system. In this way, we can obtain the dispersion curve of
polaritons, the minimum value for the cavity reflectance and the oscillator
strength to reach the strong coupling regime. This approach describes an
ensemble of excitons confined in a SQW and includes a dissipation component.
The results present a weak coupling regime, where an enhanced spontaneous
emission takes place, and a strong coupling regime, where Rabi-splitting in the
dispersion curve can be observed. The theoretical results are confronted with
experimental data for the reflectance behavior in resonant and off-resonant
conditions and present a great accuracy. This allows us to determine the
oscillator strength of the confined excitons in the SQW with great precision.Comment: 11 pages, 7 figure
Nonequilibrium dynamics of the three-dimensional Edwards-Anderson spin-glass model with Gaussian couplings: Strong heterogeneities and the backbone picture
We numerically study the three-dimensional Edwards-Anderson model with
Gaussian couplings, focusing on the heterogeneities arising in its
nonequilibrium dynamics. Results are analyzed in terms of the backbone picture,
which links strong dynamical heterogeneities to spatial heterogeneities
emerging from the correlation of local rigidity of the bond network. Different
two-times quantities as the flipping time distribution and the correlation and
response functions, are evaluated over the full system and over high- and
low-rigidity regions. We find that the nonequilibrium dynamics of the model is
highly correlated to spatial heterogeneities. Also, we observe a similar
physical behavior to that previously found in the Edwards-Anderson model with a
bimodal (discrete) bond distribution. Namely, the backbone behaves as the main
structure that supports the spin-glass phase, within which a sort of
domain-growth process develops, while the complement remains in a paramagnetic
phase, even below the critical temperature
Lattice Gauge Fixing for Parameter Dependent Covariant Gauges
We propose a non-perturbative procedure to fix generic covariant gauges on
the lattice. Varying the gauge parameter, this gauge fixing provides a concrete
method to check numerically the gauge dependence of correlators measured on the
lattice. The new algorithm turns out to converge with a good efficiency. As a
preliminary physical result, we find a sensitive dependence of the gluon
propagator on the gauge parameter.Comment: 10 pages (LaTeX2e), 5 eps figure
Isolating intrinsic noise sources in a stochastic genetic switch
The stochastic mutual repressor model is analysed using perturbation methods. This simple model of a gene circuit consists of two genes and three promotor states. Either of the two protein products can dimerize, forming a repressor molecule that binds to the promotor of the other gene. When the repressor is bound to a promotor, the corresponding gene is not transcribed and no protein is produced. Either one of the promotors can be repressed at any given time or both can be unrepressed, leaving three possible promotor states. This model is analysed in its bistable regime in which the deterministic limit exhibits two stable fixed points and an unstable saddle, and the case of small noise is considered. On small time scales, the stochastic process fluctuates near one of the stable fixed points, and on large time scales, a metastable transition can occur, where fluctuations drive the system past the unstable saddle to the other stable fixed point. To explore how different intrinsic noise sources affect these transitions, fluctuations in protein production and degradation are eliminated, leaving fluctuations in the promotor state as the only source of noise in the system. Perturbation methods are then used to compute the stability landscape and the distribution of transition times, or first exit time density. To understand how protein noise affects the system, small magnitude fluctuations are added back into the process, and the stability landscape is compared to that of the process without protein noise. It is found that significant differences in the random process emerge in the presence of protein noise
Does diversification pay in the app market? Evidence from Apple's App Store and Google Play
In this paper we address the study of the effects of product line diversification on firm performance in the mobile application market. Specifically, we shed light on whether the distribution platform ecosystem where developers commercialize their apps influence the effect of product line diversification, i.e., diversification across different app categories, on developer sales performance. To these purposes, we compare the sales performance of diversified developers with that of category-specialized developers in the two major app stores (namely, Apple’s App Store and Google Play). Our results show that the diversification strategy has a positive impact on developer sales in Google Play, while no significant impact emerges in the Apple’s App Store. The cross-platform differences in consumer willingness to pay are the rationale behind the different effect of diversification on sales performance across platform ecosystems. Our results have an important implication for developers as they suggest that developers should factor in the app ecosystem where they operate when making the decision on whether to diversify or not
An Improvement of the Pivoting Strategy in the Bunch and Kaufman Decomposition, Within Truncated Newton Methods
In this work we consider the solution of large scale (possibly nonconvex) unconstrained optimization problems. We focus on Truncated Newton methods which represent one of the commonest methods to tackle such problems. In particular, we follow the approach detailed in Caliciotti et al. (Comput Optim Appl 77:627-651, 2020), where a modified version of the Bunch and Kaufman decomposition (Bunch and Kaufman, Math Comput 31:163-179, 1977) is proposed for solving the Newton equation. Such decomposition is used within SYMMBK routine as proposed by Chandra (Conjugate gradient methods for partial differential equations, Ph.D. thesis, Yale University, New Haven, 1978; see also Conn et al., Trust-Region Methods, MPS-SIAM Series on Optimization, Philadelphia, PA, 2000; HSL: A collection of Fortran codes for large scale scientific computation, https://www.hsl.rl.ac.uki ; Marcia, Appl Numer Math 58(4):449-458, 2008) for iteratively solving symmetric possibly indefinite linear systems. The proposal in Caliciotti et al. (Comput Optim Appl 77:627-651, 2020) enabled to overcome a relevant drawback of nonconvex problems, namely the computed search direction might not be gradient-related. Here we propose further extensions of such approach, aiming at improving the pivoting strategy of the Bunch and Kaufman decomposition and enhancing its flexibility
Givu as Criminal Sanctions Tau Taa Wana Indigenous People and its Relevance to The National Criminal Justice Reform
Givu are implemented in traditional law society Tau Taa Wana is customary reaction in order to create balance and harmony between the living world and the unseen world, between human groups and individuals, as well as the fellowship (community) and society at large. Givu is a nature of mind of the basis traditional and customary law community legal awareness Tau Taa Wana. Such ceremonies clean village (village) with the aim to restore balance and perceived disruptive magical powers such rituals in the criminal justice system palampa customary Tau Taa Wana. The basic ideas of the customary criminal sanctions have not been studied in depth and accommodated to the maximum in the national legislation. Indigenous groups implement criminal sanctions customary law is not merely to uphold the image of the customary criminal law and maintain social harmony, but also to show, that the indigenous peoples still exist with cultural pluralism, in particular legal pluralism. Keywords : Customary Law, Indigenous People, Givu, Tau Taa Wana, the National Criminal Justice Reform.
Dynamics Of Legal Recognition In Indigenous Peoples Under Law Of Forestry Construction
Political developments and the struggle of indigenous peoples and indigenous as well as supporters in the national and international levels, created the ILO Convention No. 169 commonly known as the "Convention on Indigenous People Right", namely the convention on indigenous peoples and indigenous people in independent countries. The Convention was approved by 328 countries, one State against and 49 countries abstained, which underlines the implementation of human rights in general for the community customary law, also establishes the right to determine the identity, as well as determining the appropriate education of their values. They are entitled to decide the shape and development priorities, including the right to refuse development. ILO Convention 169 states customary law communities have the right to land and natural resources. Recognition of indigenous peoples, especially the juridical recognition is inseparable from the political dynamic, both in the context of national politics, cultural and political development in general. Therefore, some rules legislation issued sometimes showing obscurity recognition, or even to the efforts denial to the existence of indigenous peoples. State law and local law is the legal system that in reality there is. The state does have the right to make the adjustment to its citizens, but it does not mean that the existing legal system in the community should be replaced in its entirety by the legal system of the country. Especially when you consider that the law is the identity of a community. The placement of state law as the law is the most correct, the implications are not given the place for another law in state law. Even if the existence of other laws recognized, but still was placed on a view that inferior when compared with the laws that come from the state. Therefore, a state law that paradicmatic positivism does not see legal pluralism as a necessity and not be used as the main ideology.
Keywords: customary law community, recognition, forestry law, legal pluralis
A Socio-Legal Analysis of the Control Function of Parliament in the Regulation Implementation
UU NRI 1945 as constitution of the Republic Indonesia should be the basic source of power in order to carry out national development focused on providing an interests, kindness, and general well-being, where there is a division of powers which consists of the legislative, executive, a nd judicial. The Constitution as the source of power, not only has the legal authority and the highest authority, but also should be the basis and foundation of statehood. The Constitution of the Republic of Indonesia contains basic norms in Article 1 Paragraph (2) NRI 1945 Constitution affirms the sovereignty vested in the people and implemented through legislation. To realize the goal of interest, kindness and prosperity for the citizens of Indonesia is the supreme sovereignty vested in the people. Parliament as a representative institution of the people in the region have an important role in governance, that capable of reflecting the values of democracy also can absorb and promote the aspirations of the people including the interests of the region in accordance with the demands of the life of the nation. The Monitoring is one of the main functions that attached to the Dewan Pemerintah Daerah (DPRD) in addition to the functions of legislation and the budget. Should, aspirations of the people in the areas of supervision, institutionally represented through their elected representatives in Parliament. This supervision function is expected to become effective in accordance societal expectations, regulations and legislation in demand. DPRD monitoring aims to ensure that the regional government run the program in accordance with the plans and the statutory provisions. Supervision should constitute one of the most intensive functions that can be performed by the Institute Council. Supervisory functions executed in the context of Parliament as a political institution is a form of political control more strategic rather than technical supervision administration. It shows that the supervisory function carried by DPRD at the level of policy control to create checks and balances. Provinces that previously had a weak and limited bargaining power, strengthened by the addition of functions and authority to the governor; Fourth, efficiency and effective are preferred by grinding large areas of autonomy, real and responsible. The principles of democracy, the participation of the community, equity and equality, as well as preserve the potential and diversity areas was neglected. Keywords: Monitoring, Local Government, Political Institutions, Parliament, Local Regulation
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