4,467 research outputs found

    Single-Mode Projection Filters for Modal Parameter Identification for Flexible Structures

    Get PDF
    Single-mode projection filters are developed for eigensystem parameter identification from both analytical results and test data. Explicit formulations of these projection filters are derived using the orthogonal matrices of the controllability and observability matrices in the general sense. A global minimum optimization algorithm is applied to update the filter parameters by using the interval analysis method. The updated modal parameters represent the characteristics of the test data. For illustration of this new approach, a numerical simulation for the MAST beam structure is shown by using a one-dimensional global optimization algorithm to identify modal frequencies and damping. Another numerical simulation of a ten-mode structure is also presented by using a two-dimensional global optimization algorithm to illustrate the feasibility of the new method. The projection filters are practical for parallel processing implementation

    Projection filters for modal parameter estimate for flexible structures

    Get PDF
    Single-mode projection filters are developed for eigensystem parameter estimates from both analytical results and test data. Explicit formulations of these projection filters are derived using the pseudoinverse matrices of the controllability and observability matrices in general use. A global minimum optimization algorithm is developed to update the filter parameters by using interval analysis method. Modal parameters can be attracted and updated in the global sense within a specific region by passing the experimental data through the projection filters. For illustration of this method, a numerical example is shown by using a one-dimensional global optimization algorithm to estimate model frequencies and dampings

    "An Econometric Analysis of SARS and Avian Flu on International Tourist Arrivals to Asia"

    Get PDF
    This paper compares the impacts of SARS and human deaths arising from Avian Flu on international tourist arrivals to Asia. The effects of SARS and human deaths from Avian Flu will be compared directly according to human deaths. The nature of the short run and long run relationship is examined empirically by estimating a static line fixed effect model and a difference transformation dynamic model, respectively. Empirical results from the static fixed effect and difference transformation dynamic models are consistent, and indicate that both the short run and long run SARS effect have a more significant impact on international tourist arrivals than does Avian Flu. In addition, the effects of deaths arising from both SARS and Avian Flu suggest that SARS is more important to international tourist arrivals than is Avian Flu. Thus, while Avian Flu is here to stay, its effect is currently not as significant as that of SARS.

    The Effects Between Numerical Tabulations And Graphs Of Financial Information On The Judgment Of Investors

    Get PDF
    Due to developments in information markets and advancements in information technology, and with the rapidity of information flow on the Internet, it is vital to increase the level of information transparency. Disclosure methods of financial information have presently become an important topic of discussion. By using numerical tables, non-distorted graphs or distorted graphs of financial information, this research discusses whether financial information display types indeed influence investors’ judgments and decisions. We investigate and analyze the use of graph disclosure in Taiwan and use experiment design methods to test the effect of investors’ judgment by comparing different display types of financial information. Our results find graphs are used to display comparative than numerical financial information, showing how this can influence investors’ awareness and judgments and use of graphs can be used to manipulate impressions (impression management)

    BIOMECHANICS OF ACCURATE INSTEP KICK IN FUTSAL

    Get PDF
    The purpose of this study was to investigate the biomechanical parameters of instep kicking towards specific targets of the goal in Futsal. Twelve females from national soccer team in Taiwan were recruited in this study. Each subject was asked to perform instep kick of a stationary ball (size 4) toward targets in the four corners of the goal in Futsal. VICON motion analysis system and Kistler force plateform were used to collect the kinematics of the lower limb and the ground reaction forces and moments, respectively. The results showed that kicks towards the bottom targets demonstrated significantly greater ball velocity than towards the top targets (p= 0.00). In addition, the hip joint moment of supporting leg was significantly greater when kicking towards top targets of the goal (p= 0.01). The results of this study could provide training guidelines for coaches and players

    Sensor Selection and Integration to Improve Video Segmentation in Complex Environments

    Get PDF
    Background subtraction is often considered to be a required stage of any video surveillance system being used to detect objects in a single frame and/or track objects across multiple frames in a video sequence. Most current state-of-the-art techniques for object detection and tracking utilize some form of background subtraction that involves developing a model of the background at a pixel, region, or frame level and designating any elements that deviate from the background model as foreground. However, most existing approaches are capable of segmenting a number of distinct components but unable to distinguish between the desired object of interest and complex, dynamic background such as moving water and high reflections. In this paper, we propose a technique to integrate spatiotemporal signatures of an object of interest from different sensing modalities into a video segmentation method in order to improve object detection and tracking in dynamic, complex scenes. Our proposed algorithm utilizes the dynamic interaction information between the object of interest and background to differentiate between mistakenly segmented components and the desired component. Experimental results on two complex data sets demonstrate that our proposed technique significantly improves the accuracy and utility of state-of-the-art video segmentation technique. © 2014 Adam R. Reckley et al

    Seismic behavior of pile in liquefiable soil ground by centrifuge shaking table tests

    Get PDF
    Dramatic failure of pile foundations caused by the soil liquefaction was founded and leading to many studies on the seismic behavior of pile. The failures were often accompanied with settlement, lateral displacement and tilting of superstructures. Therefore soil-structure interaction effects must be properly considered in the design of pile. Two centrifuge models were conducted by shaking table at an acceleration field of 80 g. The purpose of this study was to investigate the seismic response of piles attached with different tip mass and embedded in liquefied or non-liquefied deposits. From the results, it was found that the maximum bending moment of pile occurs at the depth of 4 m and 5 m for dry sand and saturated sand models, respectively. The more tip mass leads to the more permanent lateral displacement and the more residual bending moment

    A Bayesian measurement error model for two-channel cell-based RNAi data with replicates

    Full text link
    RNA interference (RNAi) is an endogenous cellular process in which small double-stranded RNAs lead to the destruction of mRNAs with complementary nucleoside sequence. With the production of RNAi libraries, large-scale RNAi screening in human cells can be conducted to identify unknown genes involved in a biological pathway. One challenge researchers face is how to deal with the multiple testing issue and the related false positive rate (FDR) and false negative rate (FNR). This paper proposes a Bayesian hierarchical measurement error model for the analysis of data from a two-channel RNAi high-throughput experiment with replicates, in which both the activity of a particular biological pathway and cell viability are monitored and the goal is to identify short hair-pin RNAs (shRNAs) that affect the pathway activity without affecting cell activity. Simulation studies demonstrate the flexibility and robustness of the Bayesian method and the benefits of having replicates in the experiment. This method is illustrated through analyzing the data from a RNAi high-throughput screening that searches for cellular factors affecting HCV replication without affecting cell viability; comparisons of the results from this HCV study and some of those reported in the literature are included.Comment: Published in at http://dx.doi.org/10.1214/11-AOAS496 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Determination of AGC capacity requirement and regulation strategies considering penalties of tie-line power flow deviations

    Get PDF
    2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
    corecore