264 research outputs found

    Types of Conjugal Interactions and Conjugal Conflict: A Longitudinal Assessment

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    This paper deals with the diversity of contemporary family interactions and its consequences with regard to conjugal conflict, on the basis of a large and longitudinal survey on married and unmarried couples, conducted in Switzerland at the turn of the millennium. Using cluster analysis, we first define five types of conjugal interaction (Bastion, Companionship, Cocoon, Association, and Parallel). The types of conjugal interactions characterized by a strong emphasis on partners' autonomy trigger in the short term a significantly larger number of problems and conflicts. Conjugal dissatisfaction and separation are more likely in Associative and Parallel types of functioning. Overall, results show that conjugal modernity expresses itself through various models, each with specific functional consequence

    End-to-end congestion control for tcp-friendly flows with variable packet size

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    Current TCP-friendly congestion control mechanisms adjust the packet rate in order to adapt to network conditions and obtain a throughput not exceeding that of a TCP connection operating under the same conditions. In an environment where the bottleneck resource is packet processing, this is the correct behavior. However, if the bottleneck resource is bandwidth, and flows may use packets of different size, resource sharing depends on packet size and is no longer fair. For some applications, such as Internet telephony, it is more natural to adjust the packet size, while keeping the packet rate as constant as possible. In this paper we study the impact of variations in packet size on equation-based congestion control and propose methods to remove the resulting throughput bias. We investigate the design space in detail and propose a number of possible designs. We evaluate these designs through simulation and conclude with some concrete proposals. Our findings can be used to design a TCP-friendly congestion control mechanism for applications that adjust packet size rather than packet rate, or applications that are forced to use a small packet size

    Underwater acoustic slant range measurements related to weather and sea state

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    Underwater range measurements are key factor in underwater acoustic positioning, used in Long Base-Line (LBL) or Ultra Short Base-Line (USBL) computing techniques. These measurements are commonly carried out through acoustic communications between modems and their accuracy can be affected by different factors, such as sea state, weather conditions, and obstacles in the line of sight propagation. This is especially important in shallow waters areas, where others phenomena such as multi-path have to be considered. Therefore, range accuracy and the associated position estimation errors are an important area of research. Here, we addressed the relation between range measurements variability and sea state (i.e. currents or waves height) as proxy of real-world conditions, affecting acoustic positioning performances. For that purpose, a long-term deployment have been carried out in the underwater cabled observatory OBSEA, which provide different measurements of the sea and weather state.Peer ReviewedPostprint (published version

    A Joint PHY/MAC Architecture for Low-Radiated Power TH-UWB Wireless Ad-Hoc Networks

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    Due to environmental concerns and strict constraints on interference imposed on other networks, the radiated power of emerging pervasive wireless networks needs to be strictly limited, yet without sacrificing acceptable data rates. Pulsed Time-Hopping Ultra-Wide Band (TH-UWB) is a radio technology that has the potential to satisfy this requirement. Although TH-UWB is a multi-user radio technology, non-zero cross-correlation between time-hopping sequences, time-asynchronicity between sources and a multipath channel environment make it sensitive to strong interferers and near-far scenarios. While most protocols manage interference and multiple-access through power control or mutual exclusion (CSMA/CA or TDMA), we base our design on rate control, a relatively unexplored dimension for multiple-access and interference management. We further take advantage of the nature of pulsed TH-UWB to propose an interference mitigation scheme that reduces the impact of strong interferers. A source is always allowed to send and continuously adapts its channel code (hence its rate) to the interference experienced at the destination. In contrast to power control or exclusion, our MAC layer is local to sender and receiver and does not need coordination among neighbors not involved in the transmission. We show by simulation that we achieve a significant increase in network throughput

    Wishes or Constraints? Mothers' Labour Force Participation and its Motivation in Switzerland

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    The aim of this article is to estimate the impact of various factors related to role conflict theory and preference theory on the reduction of women's labour force participation after their transition to parenthood. Objective and subjective dimensions of women's labour force participation are assessed. The empirical test is based on a survey of couples with children in Switzerland. Results show that compared to structural factors associated with role conflict reduction, preferences have little impact on mothers' labour force participation, but explain a good deal of their frustration if the factual situation does not correspond to their wishes. Structural factors, such as occupation, economic resources, childcare, and an urban environment, support mothers' labour force participation, whereas active networks and a home centred lifestyle preference help them to cope with frustration

    Types of Conjugal Interactions and Conjugal Conflict : A Longitudinal Assessment

    Get PDF
    This paper deals with the diversity of contemporary family interactions and its consequences with regard to conjugal conflict, on the basis of a large and longitudinal survey on married and unmarried couples, conducted in Switzerland at the turn of the millennium. Using cluster analysis, we first define five types of conjugal interaction (Bastion, Companionship, Cocoon, Association, and Parallel). The types of conjugal interactions characterized by a strong emphasis on partners’ autonomy trigger in the short term a significantly larger number of problems and conflicts. Conjugal dissatisfaction and separation are more likely in Associative and Parallel types of functioning. Overall, results show that conjugal modernity expresses itself through various models, each with specific functional consequences

    Elementary Excitation Modes in a Granular Glass above Jamming

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    The dynamics of granular media in the jammed, glassy region is described in terms of "modes", by applying a Principal Component Analysis (PCA) to the covariance matrix of the position of individual grains. We first demonstrate that this description is justified and gives sensible results in a regime of time/densities such that a metastable state can be observed on long enough timescale to define the reference configuration. For small enough times/system sizes, or at high enough packing fractions, the spectral properties of the covariance matrix reveals large, collective fluctuation modes that cannot be explained by a Random Matrix benchmark where these correlations are discarded. We then present a first attempt to find a link between the softest modes of the covariance matrix during a certain "quiet" time interval and the spatial structure of the rearrangement event that ends this quiet period. The motion during these cracks is indeed well explained by the soft modes of the dynamics before the crack, but the number of cracks preceded by a "quiet" period strongly reduces when the system unjams, questioning the relevance of a description in terms of modes close to the jamming transition, at least for frictional grains.Comment: 11 pages, 10 figure
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