1,161 research outputs found

    Existence of extremal solutions for fuzzy polynomials and their numerical solutions

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    In this paper, we consider the existence of a solution for fuzzy polynomials anx^n + an−1x^n−1 + · · · + a1x + a0 = x, where ai, i = 0, 1, 2, · · · , n and x are positive fuzzy numbers satisfying certain conditions. To this purpose, we use fixed point theory, applying results such as the well-known fixed point theorem of Tarski, presenting some results regarding the existence of extremal solutions to the above equation.Peer Reviewe

    A Stateful Approach to Generate Synthetic Events from Kernel Traces

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    We propose a generic synthetic event generator from kernel trace events. The proposed method makes use of patterns of system states and environment-independent semantic events rather than platform-specific raw events. This method can be applied to different kernel and user level trace formats. We use a state model to store intermediate states and events. This stateful method supports partial trace abstraction and enables users to seek and navigate through the trace events and to abstract out the desired part. Since it uses the current and previous values of the system states and has more knowledge of the underlying system execution, it can generate a wide range of synthetic events. One of the obvious applications of this method is the identification of system faults and problems that will appear later in this paper. We will discuss the architecture of the method, its implementation, and the performance results

    A new approach for trapezoidal approximation of fuzzy numbers using WABL distance

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    In this paper, we present a new approach to obtain trapezoidal approximation of fuzzy numbers with respect to weighted distance proposed by Nasibov [5] which the main property of this metric is flexibility in the decision maker's choice. Also, we prove some properties of the proposed method such as translation invariance, scale invariance and identity. Finally, we illustrate the efficiency of proposed method by solving some numerical examples

    Efficient methods for trace analysis parallelization

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    Tracing provides a low-impact, high-resolution way to observe the execution of a system. As the amount of parallelism in traced systems increases, so does the data generated by the trace. Most trace analysis tools work in a single thread, which hinders their performance as the scale of data increases. In this paper, we explore parallelization as an approach to speedup system trace analysis. We propose a solution which uses the inherent aspects of the CTF trace format to create balanced and parallelizable workloads. Our solution takes into account key factors of parallelization, such as good load balancing, low synchronization overhead and an efficient resolution of data dependencies. We also propose an algorithm to detect and resolve data dependencies during trace analysis, with minimal locking and synchronization. Using this approach, we implement three different trace analysis programs: event counting, CPU usage analysis and I/O usage analysis, to assess the scalability in terms of parallel efficiency. The parallel implementations achieve parallel efficiency above 56% with 32 cores, which translates to a speedup of 18 times the serial speed, when running the parallel trace analyses and using trace data stored on consumer-grade solid state storage devices. We also show the scalability and potential of our approach by measuring the effect of future improvements to trace decoding on parallel efficiency

    Efficient cloud tracing: From very high level to very low level

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    With the increase of cloud infrastructure complexity, the origin of service deterioration is difficult to detect because issues may occur at the different layer of the system. We propose a multi-layer tracing approach to gather all the relevant information needed for a full workflow analysis. The idea is to collect trace events from all the cloud nodes to follow users' requests from the cloud interface to their execution on the hardware. Our approach involves tracing OpenStack's interfaces, the virtualization layer, and the host kernel space to perform analysis and show abnormal tasks and the main causes of latency or failures in the system. Experimental results about virtual machines live migration confirm that we are able to analyse services efficiency by locating platforms' weakest links

    Assessing of Preparedness for Disasters and Crisis in Centers of Trauma and Accidents of Kermanshah University of Medical Sciences in 2016

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    Background and aims: Natural and technologic disasters and accidents have great influence on people's lifestyle and their health. Main object of hospitals is providing fast and timely health care to reduce mortality and complications by the disaster. The aim of this study is to evaluate preparedness crisis and disasters in centers of trauma of Kermanshah University of Medical Sciences. Methods: The present descriptive, cross-sectional study was conducted in three hospitals (A,B,C) of Kermanshah university of medical sciences, Iran, 2016. Data were collected using a self-administered checklist and questioner through observation and interview. The checklist included 220 yes/no questions in 10 domains of emergency (30 questions), admission (24 questions), evacuation and transfer (30 questions), traffic (15 questions), communication (16 questions), security (17 questions), education (17 questions), support (28 questions), human workforce (21 questions), and leadership and management (22 items). Scores 0 and 1 were given to “No” and “Yes” choices, respectively. Data were analyzed using SPSS and descriptive statistics. Results: Overall, the relative mean of disaster preparedness in the study hospitals A, B and C was 99.1, 43.4and 84.7, respectively. Generally, the average readiness score for all hospitals was 75. The most and lowest preparedness was related to the management and traffic domains. Conclusion: According to the results, preparedness of hospitals was in the suitable level. Officials of medical centers have the necessary programs and educations in all areas of disaster preparedness for quick response and timely in hospitals

    National and regional seasonal dynamics of all-cause and cause-specific mortality in the USA from 1980 to 2016

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    In temperate climates, winter deaths exceed summer ones. However, there is limited information on the timing and the relative magnitudes of maximum and minimum mortality, by local climate, age group, sex and medical cause of death. We used geo-coded mortality data and wavelets to analyse the seasonality of mortality by age group and sex from 1980 to 2016 in the USA and its subnational climatic regions. Death rates in men and women ≥ 45 years peaked in December to February and were lowest in June to August, driven by cardiorespiratory diseases and injuries. In these ages, percent difference in death rates between peak and minimum months did not vary across climate regions, nor changed from 1980 to 2016. Under five years, seasonality of all-cause mortality largely disappeared after the 1990s. In adolescents and young adults, especially in males, death rates peaked in June/July and were lowest in December/January, driven by injury deaths
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