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1.
When applying a diagnostic technique to complex systems, whose dynamics, constraints, and environment evolve over time, being able to re-evaluate the residuals that are capable of detecting defaults and proposing the most appropriate ones can quickly prove to make sense. For this purpose, the concept of adaptive diagnosis is introduced. In this work, the contributions of information theory are investigated in order to propose a Fault-Tolerant multi-sensor data fusion framework. This work is part of studies proposing an architecture combining a stochastic filter for state estimation with a diagnostic layer with the aim of proposing a safe and accurate state estimation from potentially inconsistent or erroneous sensors measurements. From the design of the residuals, using α-Rényi Divergence (α-RD), to the optimization of the decision threshold, through the establishment of a function that is dedicated to the choice of α at each moment, we detail each step of the proposed automated decision-support framework. We also dwell on: (1) the consequences of the degree of freedom provided by this α parameter and on (2) the application-dictated policy to design the α tuning function playing on the overall performance of the system (detection rate, false alarms, and missed detection rates). Finally, we present a real application case on which this framework has been tested. The problem of multi-sensor localization, integrating sensors whose operating range is variable according to the environment crossed, is a case study to illustrate the contributions of such an approach and show the performance.  相似文献   
2.
We generalize the Jensen-Shannon divergence and the Jensen-Shannon diversity index by considering a variational definition with respect to a generic mean, thereby extending the notion of Sibson’s information radius. The variational definition applies to any arbitrary distance and yields a new way to define a Jensen-Shannon symmetrization of distances. When the variational optimization is further constrained to belong to prescribed families of probability measures, we get relative Jensen-Shannon divergences and their equivalent Jensen-Shannon symmetrizations of distances that generalize the concept of information projections. Finally, we touch upon applications of these variational Jensen-Shannon divergences and diversity indices to clustering and quantization tasks of probability measures, including statistical mixtures.  相似文献   
3.
In this article, a way to employ the diffusion approximation to model interplay between TCP and UDP flows is presented. In order to control traffic congestion, an environment of IP routers applying AQM (Active Queue Management) algorithms has been introduced. Furthermore, the impact of the fractional controller PIγ and its parameters on the transport protocols is investigated. The controller has been elaborated in accordance with the control theory. The TCP and UDP flows are transmitted simultaneously and are mutually independent. Only the TCP is controlled by the AQM algorithm. Our diffusion model allows a single TCP or UDP flow to start or end at any time, which distinguishes it from those previously described in the literature.  相似文献   
4.
We address the problem of telegraphic transport in several dimensions. We review the derivation of two and three dimensional telegrapher’s equations—as well as their fractional generalizations—from microscopic random walk models for transport (normal and anomalous). We also present new results on solutions of the higher dimensional fractional equations.  相似文献   
5.
In the assessment of most complex socioeconomic phenomena with the use of multicriteria methods, continuous data are used, the source of which are most often public statistics. However, there are complex phenomena such as quality of life and quality of services in the assessment, for which questionnaire surveys and ordinal measurement scales are used. In this case, the use of classic multicriteria methods is very difficult, taking into account the way of presenting this type of data by official statistics, as well as their permissible transformations and arithmetic operations. Therefore, the main purpose of this study was the presentation of a novel framework which can be applied for assessing socioeconomic phenomena on the basis of survey data. It was assumed that the object assessments may contain positive or negative opinions and an element of uncertainty expressed in the form a “no”, “difficult to say”, or “no opinion” answers. For this reason, the intuitionistic fuzzy TOPSIS (IF-TOPSIS) method is proposed. To demonstrate the potential of this solution, the results of measuring the subjective quality of life of the inhabitants of 83 cities in EU countries, EFTA countries, the UK, the Western Balkans, and Turkey are presented. For most cities, a high level of subjective quality of life was observed using the proposed approach. The highest level of quality of life was observed in Zurich, whereas the lowest was observed in Palermo.  相似文献   
6.
Traditional cell/particle isolation methods are time-consuming and expensive and can lead to morphology disruptions due to high induced shear stress. To address these problems, novel lab-on-a-chip-based purification methods have been employed. Among various methods introduced for the separation and purification of cells and synthetics particles, acoustofluidics has been one of the most effective methods. Unlike traditional separation techniques carried out in clinical laboratories based on chemical properties, the acoustofluidic process relies on the physical properties of the sample. Using acoustofluidics, manipulating cells and particles can be achieved in a label-free, contact-free, and highly biocompatible manner. To optimize the functionality of the platform, the numerical study should be taken into account before conducting experimental tests to save time and reduce fabrication expenses. Most current numerical studies have only considered one-dimensional harmonic standing waves to simulate the acoustic pressure distribution. However, one-dimensional simulations cannot calculate the actual acoustic pressure distribution inside the microchannel due to its limitation in considering longitudinal waves. To address this limitation, a two-dimensional numerical simulation was conducted in this study. Our numerical simulation investigates the effects of the platform geometrical and operational conditions on the separation efficiency. Next, the optimal values are tested in an experimental setting to validate these optimal parameters and conditions. This work provides a guideline for future acoustofluidic chip designs with a high degree of reproducibility and efficiency.  相似文献   
7.
Ying Yang 《中国物理 B》2021,30(11):110202-110202
The research of rogue waves is an advanced field which has important practical and theoretical significances in mathematics, physics, biological fluid mechanics, oceanography, etc. Using the reductive perturbation theory and long wave approximation, the equations governing the movement of blood vessel walls and the flow of blood are transformed into high-order nonlinear Schrödinger (NLS) equations with variable coefficients. The third-order nonlinear Schrödinger equation is degenerated into a completely integrable Sasa-Satsuma equation (SSE) whose solutions can be used to approximately simulate the real rogue waves in the vessels. For the first time, we discuss the conditions for generating rogue waves in the blood vessels and effects of some physiological parameters on the rogue waves. Based on the traveling wave solutions of the fourth-order nonlinear Schrödinger equation, we analyze the effects of the higher order terms and the initial deformations of the blood vessel on the wave propagation and the displacement of the tube wall. Our results reveal that the amplitude of the rogue waves are proportional to the initial stretching ratio of the tube. The high-order nonlinear and dispersion terms lead to the distortion of the wave, while the initial deformation of the tube wall will influence the wave amplitude and wave steepness.  相似文献   
8.
余鹏  马珩 《运筹与管理》2021,30(3):177-182
借助“制造业高级化”产业升级理论, 从结构优度、价值链高度、环境保护程度三个维度构建制造业产业升级评价指标体系。根据TOPSIS思想, 以被评价对象数列和理想方案指标数列两相邻点间围成图形的面积来表征关联系数, 同时采用标准差修正G1组合赋权原理对指标赋权并进一步计算灰关联相对贴近度; 通过引入时间变量并赋予时间序列权重以实现对长三角制造业产业升级动态评价。研究结果显示:2010至2016年间, 上海市排名最高, 江苏省略高于浙江省, 安徽省最低; 安徽省是长三角制造业产业升级的短板。基于上述结论, 给出长三角制造业产业升级的政策建议。  相似文献   
9.
为提高生鲜羊肉储存期内(4,8和20 ℃环境)挥发性盐基氮(TVB-N)的近红外光谱(NIR)检测的稳定性和准确性,选取特征光谱和预测模型是关键步骤。以121个羊肉样品为实验对象,采集生鲜羊肉680~2 600 nm波段的近红外光谱。以多元散射校正(MSC)、标准正态变换(SNV)等散射校正方法,Savitzky-Golay卷积平滑(SGS)、移动平均平滑(MAS)等平滑处理方法,以及归一化(Normalization)、中心化(Centering)、标准化(Autoscaling)等尺度缩放方法分别预处理光谱数据后建立偏最小二乘法(PLS)预测模型。比较发现SGS处理的光谱建模效果最好。利用蒙特卡洛采样(MCS)法及马氏距离法(MD)消除了羊肉光谱的5个异常数据。运用光谱-理化值共生距离(SPXY)算法划分总样本的75%(87个)为校正集样本,剩余29个为验证集样本,利用竞争性自适应重加权法(CARS)、无信息变量消除法(UVE)、改进的无信息变量消除法(IUVE)和连续投影算法(SPA)提取特征光谱得到的波长个数分别为14,713,144和15。将全光谱和4种方法提取的特征波长作为输入变量建立预测模型,CARS提取的波长所建立模型的性能优于UVE、IUVE和SPA提取的波长所建立模型的性能,表明CARS方法可以有效简化输入变量并提高预测模型的性能。改进后得到的IUVE法相比于UVE法,筛选出的波长数更少且模型性能有所提升。以提取的特征波长建立PLS,支持向量机(SVM)和最小二乘支持向量机(LS-SVM)预测模型,SVM模型得到最优的校正集预测结果,其中CARS-SVM预测模型的校正决定系数(R2C)和校正均方根误差(RMSEC)分别为0.939 1和1.426 7,最优的验证集预测效果为LS-SVM预测模型得到,其中IUVE-LS-SVM预测模型的验证决定系数(R2V)和验证均方根误差(RMSEV)分别为0.856 8和1.886 2。基于近红外特征光谱建立简化、优化的生鲜羊肉储存期TVB-N预测模型,为实现快速无损检测生鲜羊肉中的TVB-N浓度提供技术支持。  相似文献   
10.
Active inference is a physics of life process theory of perception, action and learning that is applicable to natural and artificial agents. In this paper, active inference theory is related to different types of practice in social organization. Here, the term social organization is used to clarify that this paper does not encompass organization in biological systems. Rather, the paper addresses active inference in social organization that utilizes industrial engineering, quality management, and artificial intelligence alongside human intelligence. Social organization referred to in this paper can be in private companies, public institutions, other for-profit or not-for-profit organizations, and any combination of them. The relevance of active inference theory is explained in terms of variational free energy, prediction errors, generative models, and Markov blankets. Active inference theory is most relevant to the social organization of work that is highly repetitive. By contrast, there are more challenges involved in applying active inference theory for social organization of less repetitive endeavors such as one-of-a-kind projects. These challenges need to be addressed in order for active inference to provide a unifying framework for different types of social organization employing human and artificial intelligence.  相似文献   
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