5,247 research outputs found

    Earthquake Early Warning and Beyond: Systems Challenges in Smartphone-based Seismic Network

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    Earthquake Early Warning (EEW) systems can effectively reduce fatalities, injuries, and damages caused by earthquakes. Current EEW systems are mostly based on traditional seismic and geodetic networks, and exist only in a few countries due to the high cost of installing and maintaining such systems. The MyShake system takes a different approach and turns people's smartphones into portable seismic sensors to detect earthquake-like motions. However, to issue EEW messages with high accuracy and low latency in the real world, we need to address a number of challenges related to mobile computing. In this paper, we first summarize our experience building and deploying the MyShake system, then focus on two key challenges for smartphone-based EEW (sensing heterogeneity and user/system dynamics) and some preliminary exploration. We also discuss other challenges and new research directions associated with smartphone-based seismic network.Comment: 6 pages, conference paper, already accepted at hotmobile 201

    Persistence and ability in the innovation decisions

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    The main concern of this paper is to analyse the complementarities between the decisions to carry out both product and process innovations. We also try to identify the main determinants of the innovation activity as well as to separate the experience effect of the firm (capacities, routines as organization) from the experience effect of the manager (skills, abilities). It has been common when facing the study of technological change, to consider innovation as a homogeneous activity. The main analyses have focused on the determinants of such activity trying to explain decisions, counts or R and D expenses in the context of a unique activity. Several recent works, however, are worried about the possibility of analysing innovation distinguishing among different types according to the final purpose of this activity. We focus on two different decisions, product and process innovations, using typical discrete choice specifications (univariate and bivariate models) and also binary choice models with heterogeneity. Among the results, we find complementary but asymmetric effects concerning both decisions in static models even controlling heterogeneity. We also test whether the persistence in conducting innovation activities matter. We do so in an extensive database that provides information about manufacturing firms. Our results point towards the importance of both ability of the manager (unobserved heterogeneity) and experience of the firm (dynamics in the equation indicator)

    PERSISTENCE AND ABILITY IN THE INNOVATION DECISIONS

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    The main concern of this paper is to analyse the complementarities between the decisions to carry out both product and process innovations. We also try to identify the main determinants of the innovation activity as well as to separate the experience effect of the firm (capacities, routines as organization) from the experience effect of the manager (skills, abilities). It has been common when facing the study of technological change, to consider innovation as a homogeneous activity. The main analyses have focused on the determinants of such activity trying to explain decisions, counts or R&D expenses in the context of a unique activity. Several recent works, however, are worried about the possibility of analysing innovation distinguishing among different types according to the final purpose of this activity. We focus on two different decisions, product and process innovations, using typical discrete choice specifications (univariate and bivariate models) and also binary choice models with heterogeneity. Among the results, we find complementary but asymmetric effects concerning both decisions in static models even controlling heterogeneity. We also test whether the persistence in conducting innovation activities matter. We do so in an extensive database that provides information about manufacturing firms. Our results point towards the importance of both ability of the manager (unobserved heterogeneity) and experience of the firm (dynamics in the equation indicator).

    Extreme(ly) mean(ingful): Sequential formation of a quality group

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    The present paper studies the limiting behavior of the average score of a sequentially selected group of items or individuals, the underlying distribution of which, FF, belongs to the Gumbel domain of attraction of extreme value distributions. This class contains the Normal, Lognormal, Gamma, Weibull and many other distributions. The selection rules are the "better than average" (ÎČ=1\beta=1) and the "ÎČ\beta-better than average" rule, defined as follows. After the first item is selected, another item is admitted into the group if and only if its score is greater than ÎČ\beta times the average score of those already selected. Denote by Yˉk\bar{Y}_k the average of the kk first selected items, and by TkT_k the time it takes to amass them. Some of the key results obtained are: under mild conditions, for the better than average rule, Yˉk\bar{Y}_k less a suitable chosen function of log⁥k\log k converges almost surely to a finite random variable. When 1−F(x)=e−[xα+h(x)]1-F(x)=e^{-[x^{\alpha}+h(x)]}, α>0\alpha>0 and h(x)/xα⟶x→∞0h(x)/x^{\alpha}\stackrel{x\rightarrow \infty}{\longrightarrow}0, then TkT_k is of approximate order k2k^2. When ÎČ>1\beta>1, the asymptotic results for Yˉk\bar{Y}_k are of a completely different order of magnitude. Interestingly, for a class of distributions, TkT_k, suitably normalized, asymptotically approaches 1, almost surely for relatively small ÎČ≄1\beta\ge1, in probability for moderate sized ÎČ\beta and in distribution when ÎČ\beta is large.Comment: Published in at http://dx.doi.org/10.1214/10-AAP684 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Towards Distributed Convoy Pattern Mining

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    Mining movement data to reveal interesting behavioral patterns has gained attention in recent years. One such pattern is the convoy pattern which consists of at least m objects moving together for at least k consecutive time instants where m and k are user-defined parameters. Existing algorithms for detecting convoy patterns, however do not scale to real-life dataset sizes. Therefore a distributed algorithm for convoy mining is inevitable. In this paper, we discuss the problem of convoy mining and analyze different data partitioning strategies to pave the way for a generic distributed convoy pattern mining algorithm.Comment: SIGSPATIAL'15 November 03-06, 2015, Bellevue, WA, US

    Penggunaan Metode Story Telling melalui Multimedia untuk Mencegah dan Mengatasi Perilaku Menyimpang Kelas X

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    This research is based by the increasing of deviant behavior occurrence among learners, especially in senior high school. This should be handled with specific learning. The general aim of this research is to produce the learning resources of story telling method through multimedia to prevent and cope deviant behavior in class X SMA. The study was conducted with product development (Research and Development) with naturalistic qualitative approach, and data that is processed with the analysis of qualitative data, as well as snowball sampling with sampilng. The expression of learners class X SMA I Jagoi Babang are deep feelings of the learners which appears reactions or attitude as the expression of learners who really touched, sad, high motivation to continue the struggle (ideals) and avoid deviant behavior in daily life at school, at home, and the community in positive attitude and a variety of real work

    Constructing an advanced software tool for planetary atmospheric modeling

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    Scientific model building can be an intensive and painstaking process, often involving the development of large and complex computer programs. Despite the effort involved, scientific models cannot be easily distributed and shared with other scientists. In general, implemented scientific models are complex, idiosyncratic, and difficult for anyone but the original scientist/programmer to understand. We believe that advanced software techniques can facilitate both the model building and model sharing process. In this paper, we describe a prototype for a scientific modeling software tool that serves as an aid to the scientist in developing and using models. This tool includes an interactive intelligent graphical interface, a high level domain specific modeling language, a library of physics equations and experimental datasets, and a suite of data display facilities. Our prototype has been developed in the domain of planetary atmospheric modeling, and is being used to construct models of Titan's atmosphere
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