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1,331 records were found.

Siberia is legendary: vast expanses of land, crisp cold, punishment camps, but also apparently inexhaustible natural riches and mineral resources. For some of the indigenous “Peoples of the North” who live there, reindeer herding, together with hunting and fishing, is still a core element of everyday life. The Siberia Project Group at the MAX PLANCK INSTITUTE FOR SOCIAL ANTHROPOLOGY in Halle is investigating how this has changed since the collapse of the Soviet Union. DR. PATTY A. GRAY and FLORIAN STAMMLER, members of the group situated within Prof. Chris Hann’s department, describe results from their analysis of Yamal and Chukotka.
In this paper we present measurements made using an 802.11e wireless testbed. We demonstrate experimentally how the new 802.11e [1] QoS parameters behave in our testbed. We describe the testing methodology used to validate the operation of the 802.11e TXOP, AIFS and CWmin parameters and compare the experimental results to existing analytical models. We also discuss a number of practical issues encountered during our measurements. We then use the testbed to demonstrate some known problems with TCP’s performance caused by cross-layer interaction between the TCP congestion control algorithm and the MAC layer CSMA/CA contention mechanism. Finally, we study how these problems can be mitigated using the flexibility provided by the 802.11e parameters via the scheme suggested in [2].
In a model of rational agent choice in which agents value consumption and leisure as well as health, we establish that individuals, unconstrained by concerns of income or time, can and will choose levels of consumption and leisure that exceed their physiological optima. By how much they exceed the optima depends on a variety of factors, most importantly, the utility cost (benefit) of achieving health. Observed positive long-run trends in adult weight, brought on by higher levels of consumption and lower levels of physical activity, often interpreted as a public health crisis in the making, can be explained by these factors. But, rather than the trend suggesting crisis, it suggests only optimal responses to altered, and perhaps improved, circumstances. While individuals today, all else equal, may weigh more than those a generati...
In this paper, we present a probabilistic synchronization algorithm whose convergence properties are examined using tools of rowstochastic matrices. The proposed algorithm is particularly well suited for wireless sensor network applications, where connectivity is not guaranteed at all times, and energy efficiency is an important design consideration. The tradeoff between the convergence speed and the energy use is studied.
The problem of finding network codes for general connections is inherently difficult. Resource minimization for general connections with network coding is further complicated. The existing solutions mainly rely on very restricted classes of network codes, and are almost all centralized. In this paper, we introduce linear network mixing coefficients for code constructions of general connections that generalize random linear network coding (RLNC) for multicast connections. For such code constructions, we pose the problem of cost minimization for the subgraph involved in the coding solution and relate this minimization to a Constraint Satisfaction Problem (CSP) which we show can be simplified to have a moderate number of constraints. While CSPs are NP-complete in general, we present a probabilistic distributed algorithm with ...
• Purpose - This paper offers a critical review of how self-initiated expatriation (SIE) is theorized compared to migration in the management literature and indicates avenues for future research on SIE. • Design/methodology/approach – A systematic review has been conducted using the ISI Web of Knowledge database as well as ABI/INFORM in order to include key journals in the management field. • Findings – Despite the importance of present theorizations on SIE, we show that the literature presents a narrow focus on the most privileged of self-initiated expatriates and presents some important knowledge gaps. In order to fill these gaps, we propose a research map for future research on SIE. Our map includes four key dimensions. These are: 1) diversity-informed research on SIE; 2) context specific and multilevel understanding of S...
When assessing the power emitted from a Wi-Fi network, it has been observed that these networks operate at a relatively low duty cycle. In this paper, we extend a recently introduced model of emitted power in Wi-Fi networks to cover conditions where devices do not always have packets to transmit. We present experimental results to validate the original model and its extension by developing approximate, but practical, testbed measurement techniques. The accuracy of the models is confirmed, with small relative
Morphological development of fungi and their combined production of secondary metabolites are both acting in defence and protection. These processes are mainly coordinated by velvet regulators, which contain a yet functionally and structurally uncharacterized velvet domain. Here we demonstrate that the velvet domain of VosA is a novel DNA-binding motif that specifically recognizes an 11-nucleotide consensus sequence consisting of two motifs in the promoters of key developmental regulatory genes. The crystal structure analysis of the VosA velvet domain revealed an unforeseen structural similarity with the Rel homology domain (RHD) of the mammalian transcription factor NF-kB. Based on this structural similarity several conserved amino acid residues present in all velvet domains have been identified and shown to be essential for the DNA ...
The purpose of this article is to present a case for the importance of research in informing mediation practice specifically in the context of the management of workplace conflict in Ireland. The position of mediation within the broader dispute-resolution framework is clarified at the outset and the core mediation process is described. The increasing use of mediation in Ireland and the changing institutional context within which it is conducted are discussed. The importance of research is stressed along with crucial methodological challenges. The paucity of workplace mediation research in Ireland is highlighted and the preliminary findings of an on-going research project are presented. The article concludes that more research into workplace mediation in Ireland is needed to inform practice in this area and to improve external perceptio...
Constraint satisfaction problems (CSPs) lie at the heart of many modern industrial and commercial tasks. An important new collection of CSPs has recently been emerging that differ from classical problems in that they impose constraints on the class of algorithms that can be used to solve them. In computer network applications, these constraints arise as the variables within the CSP are located at physically distinct devices that cannot communicate. At each instant, every variable only knows if all its constraints are met or at least one is not. Consequently, the CSP’s solution must be found using a decentralized approach. Existing algorithms for solving CSPs are either centralized or distributed, both of which fundamentally violate these algorithmic constraints. In this article we present the first algorithm for solving CS...