Earnings and Percentage Female: A Longitudinal Study

Comparable worth is designed to raise the earnings of women assumed to be penalized for working in female-dominated occupations. Comparable worth advocates assume that the relation between earnings and percentage female in an occupation is due to crowding or other forms of discrimination. An alternative explanation is that the relation stems from women freely choosing different occupations. In other words, preferences are an omitted variable. In our study, we first replicate previous research that has used cross-sectional data to find a negative relation between earnings and percentage female (in an occupation) for both men and women. However, using longitudinal data to control for time-invariant omitted variables, we find that while men\u27s estimated penalty is not reduced, the percentage female penalty falls substantially for women and is not statistically significant. These results imply that estimates of the percentage female effect based on cross-sectional data may be inflated for women. An exception to this general finding is that women with intermittent labor force participation do experience a sizeable penalty for working in female-dominated occupations. Hence, this pattern of results suggests that a comparable worth policy would most likely benefit women with discontinuous employment--perhaps an unintended outcome

Etude de l'interface milieu granulaire-paroi rugueuse par approches expérimentale et numérique - Application aux bétons

International audienceLa qualité des parements, les poussées et le pompage des bétons sont liés au frottement du béton contre la paroi. L'objectif de cette étude est de comprendre les phénomènes se produisant à l'interface béton frais-paroi à l'échelle des grains. L'étude de l'interface a été réalisée sur un modèle simplifié qui consiste à déplacer une paroi rugueuse sous un empilement monodisperse confiné. Des expériences sur un dispositif expérimental et des simulations sur un modèle numérique aux éléments discrets ont été menées. Les résultats expérimentaux montrent qu'à proximité de l'interface, les mouvements de billes dépendent de la rugosité de la paroi. De même, l'étude numérique montre que la force de frottement et l'état de cisaillement près de l'interface sont étroitement liés aux caractéristiques de la paroi rugueuse

Power Optimisation and Relay Selection in Cooperative Wireless Communication Networks

Cooperative communications have emerged as a significant concept to improve reliability and throughput in wireless systems. In cooperative networks, the idea is to implement a scheme in wireless systems where the nodes can harmonize their resources thereby enhancing the network performance in different aspects such as latency, BER and throughput. As cooperation spans from the basic idea of transmit diversity achieved via MIMO techniques and the relay channel, it aims to reap somewhat multiple benefits of combating fading/burst errors, increasing throughput and reducing energy use. Another major benefit of cooperation in wireless networks is that since the concept only requires neighbouring nodes to act as virtual relay antennas, the concept evades the negative impacts of deployment costs of multiple physical antennas for network operators especially in areas where they are difficult to deploy. In cooperative communications energy efficiency and long network lifetimes are very important design issues, the focus in this work is on ad hoc and sensor network varieties where the nodes integrate sensing, processing and communication such that their cooperation capabilities are subject to power optimisation. As cooperation communications leads to trade-offs in Quality of Services and transmit power, the key design issue is power optimisation to dynamically combat channel fluctuations and achieve a net reduction of transmit power with the goal of saving battery life. Recent researches in cooperative communications focus on power optimisation achieved via power control at the PHY layer, and/or scheduling mechanism at the MAC layer. The approach for this work will be to review the power control strategy at the PHY layer, identify their associated trade-offs, and use this as a basis to propose a power control strategy that offers adaptability to channel conditions, the road to novelty in this work is a channel adaptable power control algorithm that jointly optimise power allocation, modulation strategy and relay selection. Thus, a novel relay selection method is developed and implemented to improve the performance of cooperative wireless networks in terms of energy consumption. The relay selection method revolves on selection the node with minimum distance to the source and destination. The design is valid to any wireless network setting especially Ad-hoc and sensor networks where space limitations preclude the implementation of bigger capacity battery. The thesis first investigates the design of relay selection schemes in cooperative networks and the associated protocols. Besides, modulation strategy and error correction code impact on energy consumption are investigated and the optimal solution is proposed and jointly implemented with the relay selection method. The proposed algorithm is extended to cooperative networks in which multiple nodes participate in cooperation in fixed and variable rate system. Thus, multi relay selection algorithm is proposed to improve virtual MIMO performance in terms of energy consumption. Furthermore, motivated by the trend of cell size optimisation in wireless networks, the proposed relay selection method is extended to clustered wireless networks, and jointly implemented with virtual clustering technique. The work will encompass three main stages: First, the cooperative system is designed and two major protocols Decode and Forward (DF) and amplify and forward (AF) are investigated. Second, the proposed algorithm is modelled and tested under different channel conditions with emphasis on its performance using different modulation strategies for different cooperative wireless networks. Finally, the performance of the proposed algorithm is illustrated and verified via computer simulations. Simulation results show that the distance based relay selection algorithm exhibits an improved performance in terms of energy consumption compared to the conventional cooperative schemes under different cooperative communication scenarios

THE PARTICIPATORY APPROACH FOR WATERFRONT DEVELOPMENT IN MEDITERRANEAN COUNTRIES. A CASE STUDY OF TRIPOLI, LEBANON WATERFRONT

Public waterfronts are considered an important touristic target in coastal cities. The development of these spaces is affected by many social, economic and political issues. Public participation has been an important tool for communities to influence the making of public spaces. This research aims to develop a participatory approach for waterfront development in Mediterranean countries by studying people behavior and activities on public waterfronts and investigating the socio-economic factors that influence the usage of these areas. It is a bottom-up approach that analyzes how activities emerged from people needs. This research is a mixture of qualitative and quantitative approaches that undertakes a case study with its activities and is based on socio-economic studies, behavioral and physical analysis. The used tools and techniques are: documentation, direct observations, lengthy-interviews and questionnaires with stakeholders (users and visitors). This paper is a preliminary study and part of an ongoing PhD research where the outcome will be a participatory matrix approach dedicated to decision makers to facilitate the effective participation of stakeholders in development of the waterfront. Also, it should improves the waterfront economic status, enhances the development and allows the new plans to be implemented in order to make a valuable public space open to the all citizens and tourist

Spectrum Sensing of DVB-T2 Signals in Multipath Channels for Cognitive Radio Networks

© 2018 VDE VERLAG GMBHIn this paper, spectrum sensing of digital video broadcasting-second generation terrestrial (DVB-T2) signals in different fading environments with energy detection (ED) is considered. ED is known to achieve an increased performance among low computational complexity detectors, but it is susceptible to noise uncertainty. By taking into consideration the edge pilot and scattered pilot periodicity in DVB-T2 signals, a low computational complex noise power estimator is proposed. It is shown analytically that the choice of detector depends on the environment, the detector requirements, the available prior knowledge and with the noise power estimator. Simulation confirm that with the noise power estimator, ED significantly outperforms the pilot correlation-based detectors. Simulation also show that the proposed scheme enables ED to obtain increased detection performance in fading channels

Spectrum Sensing of DVB-T2 Signals using a Low Computational Noise Power Estimation

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted ncomponent of this work in other works.Cognitive radio is a promising technology that answers the spectrum scarcity problem arising from the proliferation of wireless networks and mobile services. In this paper, spectrum sensing of digital video broadcasting-second generation terrestrial (DVB-T2) signals in AWGN, WRAN and COST207 multipath fading environment are considered. ED is known to achieve an increased performance among low computational complexity detectors, but it is susceptible to noise uncertainty. Taking into consideration the edge pilot and scattered pilot periodicity in DVB-T2 signals, a low computational noise power estimator is proposed. Analytical forms for the detector are derived. Simulation results show that with the noise power estimator, ED significantly outperforms the pilot correlation-based detectors. Simulation also show that the proposed scheme enables ED to obtain increased detection performance in multi-path fading environments. Moreover, based on this algorithm a practical sensing scheme for cognitive radio networks is proposed.Peer reviewedFinal Accepted Versio

El género de la «muerte» en el Kitāb al-‘iqd al-Farīd

This article studies a subsection of the adab compilation of Ibn ‘Abd Rabbih’s, al-‘Iqd al-farīd, namely “The Book of Lamentations, Condolences, and Elegies”. The article analyzes al-‘Iqd’s ideological function, specifically, the way gender is organized through the occasion of death. It locates what seems to be «repressed» in the text attempting to determine what material was ignored, buried, end edited, and how priorities were arranged. It is the contention of this article that al-‘Iqd, as an exemplary text, not only reflects a dominant ideology, but contributes towards the dominant discourse by shaping mental and social life.Este artículo estudia la sección de la recopilación de adab del ‘Iqd al-farīd de Ibn ‘Abd Rabbih llamada “El Libro de Lamentaciones, Condolencias y Elegías”. Se analiza la función ideológica del ‘Iqd, concretamente la manera en que se organiza el género con ocasión de la muerte. Localiza lo que parece haberse «reprimido» en el texto en un intento por determinar el material que fue pasado por alto, enterrado o alterado, y estudia la organización de sus prioridades. El artículo sostiene que el ‘Iqd, en su función de texto ejemplar, no se limita a reflejar una ideología dominante sino que hace una contribución al discurso dominante por su manera de dar forma a la vida intelectual y social

Modeling circadian clock-cell cycle interaction effects on cell population growth rates

Accepted for publication in Journal of Theoretical Biology, post-print versionInternational audienceThe circadian clock and the cell cycle are two tightly coupled oscillators. Recent analytical studies have shown counter-intuitive effects of circadian gating of the cell cycle on growth rates of proliferating cells which cannot be explained by a molecular model or a population model alone. In this work, we present a combined molecular-population model that studies how coupling the circadian clock to the cell cycle, through the protein WEE1, affects a proliferating cell population. We show that the cell cycle can entrain to the circadian clock with different rational period ratios and characterize multiple domains of entrainment. We show that coupling increases the growth rate for autonomous periods of the cell cycle around 24 h and above 48 h. We study the effect of mutation of circadian genes on the growth rate of cells and show that disruption of the circadian clock can lead to abnormal proliferation. Particularly, we show that $\mathit{Cry1}$, $\mathit{Cry2}$ mutations decrease the growth rate of cells, $\mathit{Per2}$ mutation enhances it and $\mathit{Bmal1}$ knockout increases it for autonomous periods of the cell cycle less than 21 h and decreases it elsewhere. Combining a molecular model to a population model offers new insight on the influence of the circadian clock on the growth of a cell population. This can help chronotherapy which takes benefits of physiological rhythms to improve anti-cancer efficacy and tolerance to drugs by administering treatments at a specific time of the day

Structural build-up of cementitious paste with nano-Fe3O4 under time-varying magnetic fields

The structural build-up of cementitious paste with nano-Fe3O4 under time-varying magnetic fields was experimentally investigated using small amplitude oscillatory shear (SAOS) technique. Several modes of magnetic fields, such as constant, sudden-changed and linearly-changed, were applied to the cementitious paste. Results showed that the structural build-up of the cementitious paste depended on the magnetizing time and magnetic field strength. Applying constant magnetic fields improved the liquid-like behavior during first minutes and afterwards the solid-like property was enhanced. Both the sudden-increased and sudden-decreased magnetic fields resulted in a sharp decrease in storage modulus. The linearly increasing magnetic field resulted in a slight increase in storage modulus but higher liquid-like behavior. When the magnetic field was linearly decreased from 0.5 T to approx. 0.25 T, the structural build-up was enhanced significantly, and with the continuously decreasing magnetic field from approx. 0.25 T to 0 T, a decrease in storage modulus was observed