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61.
A configurable process model provides a consolidated view of a family of business processes. It promotes the reuse of proven practices by providing analysts with a generic modeling artifact from which to derive individual process models. Unfortunately, the scope of existing notations for configurable process modeling is restricted, thus hindering their applicability. Specifically, these notations focus on capturing tasks and control-flow dependencies, neglecting equally important ingredients of business processes such as data and resources. This research fills this gap by proposing a configurable process modeling notation incorporating features for capturing resources, data and physical objects involved in the performance of tasks. The proposal has been implemented in a toolset that assists analysts during the configuration phase and guarantees the correctness of the resulting process models. The approach has been validated by means of a case study from the film industry.  相似文献   
62.
A smart Information and Communication Technology (ICT) enables a synchronized interplay of different key factors, aligning infrastructures, consumers, and governmental policy-making needs. In the harbor’s logistics context, smart ICT has been driving a multi-year wave of growth. Although there is a standalone value in the technological innovation of a task, the impact of a new smart technology is unknown without quantitative analysis methods on the end-to-end process. In this paper, we first present a review of the smart ICT for marine container terminals, and then we propose to evaluate the impact of such smart ICT via business process model and notation (BPMN) modeling and simulation. The proposed approach is discussed in a real-world modeling and simulation analysis, made on a pilot terminal of the Port of Leghorn (Italy).  相似文献   
63.
In this paper, the problem of residual variance estimation is examined. The problem is analyzed in a general setting which covers non-additive heteroscedastic noise under non-iid sampling. To address the estimation problem, we suggest a method based on nearest neighbor graphs and we discuss its convergence properties under the assumption of a Hölder continuous regression function. The universality of the estimator makes it an ideal tool in problems with only little prior knowledge available.  相似文献   
64.
基于实体模型的三维真实感流动模拟软件的研究与开发   总被引:6,自引:0,他引:6  
注射成型的流动模拟在预测复杂薄壁型腔的流动行为方面已经比较准确。现行的数值方法主要采用基于中性层的有限元/有限差分/控制体积法,但中性层模型的引入使得模拟软件在应用中具有极大的局限性。本文采用实体模型取代中性层模型,开发了三维真实感流动模拟软件。最后,应用实例证明此模型能够处理由流行CAD系统生成的复杂型腔模型。  相似文献   
65.
Nearshore small fish species represent a large proportion of fish biodiversity in Lake Simcoe, a large inland lake in southern Ontario, Canada. Over the past 30 years, Lake Simcoe has experienced several changes to its aquatic habitat, benthic invertebrate communities and predatory fish populations. This study compared samples of the nearshore small fish community in three geographic areas of Lake Simcoe. Fish community data were grouped into two time periods: a contemporary period (2007–2009) and a historical period (1982–1995). The fish community was compared across time periods for each area to assess if observed ecological changes had an impact on the small fish community. Species richness significantly declined between time periods in two areas (Cook's Bay and the southeast shoreline), the number of individuals captured declined between time periods in one area of the lake (Kempenfelt Bay) and Simpson's diversity index declined between time periods in one area of the lake (southeast shoreline). There were no significant differences in the Shannon–Weiner evenness index between time periods in any of the study areas. Additional analyses of intra- and inter-annual variation in fish sampling results generally supported the findings that shifts in the fish community occurred between time periods. Overall, this study suggests that the nearshore small fish biodiversity of Lake Simcoe has shifted over time but these shifts are not clearly related to recent increases in water clarity, macrophyte growth and nearshore benthic invertebrate densities.  相似文献   
66.
针对均值移动算法鲁棒性差以及粒子滤波算法计算量大、难以满足实时跟踪的特点,提出2种先均值移动后粒子滤波的融合算法,分别为粒子数目保持恒定的融合算法和粒子数目自适应的融合算法。实验结果证明,与已有算法相比,2种算法在实时性提高的同时,跟踪准确性和抗干扰能力没有明显下降。  相似文献   
67.
This paper presents an approach for improving the control limits of $ \overline{X} $ control charts when the parameters of the process are estimated and the control chart is in operation. In these conditions, the observed average run length (ARL) may be very different from the planned ARL since the parameter estimates may have a larger error. To minimize this problem, the data collected in effective control (phase 2) will be used to re-estimate the parameters with a precision greater than that obtained in phase 1. Thus, we defined a minimum sample size of observations of phase 2, which is constituted of a mixture of two normal distributions that should be used to re-estimate the process parameters. The proposal is illustrated with numerical example.  相似文献   
68.
A novel implementation of a rail-to-rail exponential voltage to voltage converter is presented. It is based on a pseudo-exponential approximation that is easily achieved by the nonlinear currents of a class-AB transconductor. Measurement results for a 0.5 /spl mu/m CMOS technology show a 52 dB output voltage range with linearity error less than /spl plusmn/2 dB using a dual supply voltage of /spl plusmn/750 mV. The power dissipation is less than 40 /spl mu/W.  相似文献   
69.
A methodology has been developed to evaluate the reliability of passive systems characterised by a moving fluid and whose operation is based on thermal–hydraulic (T-H) principles. The methodology includes:
• identification and quantification of the sources of uncertainties and determination of the important variables;
• propagation of the uncertainties through T-H models and assessment of T-H passive system unreliability;
• introduction of passive system unreliability in the accident sequence analysis.
Each step of the methodology is described and commented and a diagram of the methodology is presented. An example of passive system is presented with the aim to illustrate the possibilities of the methodology. This example is the Residual Passive heat Removal system on the Primary circuit (RP2), an innovating system supposed to be implemented on a 900 MWe Pressurized Water Reactor.  相似文献   
70.
反应气相色谱法测定饮用水中的氯乙酸   总被引:4,自引:0,他引:4  
采用固相提取法从饮用水中分离出氯乙酸进行酯化,并将其转化为三氟乙酸酯,通过实验确定了最佳酯化条件,并用电子俘获检测器进行气相色谱分离和测定。  相似文献   
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