Regularized system identification has become the research frontier of system identification in the past *** related core subject is to study the convergence properties of various hyper-parameter estimators as the samp...
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Regularized system identification has become the research frontier of system identification in the past *** related core subject is to study the convergence properties of various hyper-parameter estimators as the sample size goes to *** this paper,we consider one commonly used hyper-parameter estimator,the empirical Bayes(EB).Its convergence in distribution has been studied,and the explicit expression of the covariance matrix of its limiting distribution has been ***,what we are truly interested in are factors contained in the covariance matrix of the EB hyper-parameter estimator,and then,the convergence of its covariance matrix to that of its limiting distribution is *** general,the convergence in distribution of a sequence of random variables does not necessarily guarantee the convergence of its covariance ***,the derivation of such convergence is a necessary complement to our theoretical analysis about factors that influence the convergence properties of the EB hyper-parameter *** this paper,we consider the regularized finite impulse response(FIR)model estimation with deterministic inputs,and show that the covariance matrix of the EB hyper-parameter estimator converges to that of its limiting ***,we run numerical simulations to demonstrate the efficacy of ourtheoretical results.
Computational Fluids Dynamics(CFD)simulations are essential for optimizing the design of a cockpit’s internal environment,but the complex geometric models consume a significant amount of computational resources and *...
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Computational Fluids Dynamics(CFD)simulations are essential for optimizing the design of a cockpit’s internal environment,but the complex geometric models consume a significant amount of computational resources and *** simplification of geometric models may result in inaccurate calculations of physical *** address this issue,this study establishes a geometric model simplification strategy and successfully applies it to a *** implementation of the whole approach is divided into three steps,summarized in three methods,namely Sensitivity Analysis Method(SAM),Detail Suppression Method(DSM),and Evaluation Standards Method(ESM).Sensitivity analysis of the detailed features of the geometric model is performed using the adjoint *** details of the geometric model are suppressed based on the principle of curvature *** evaluation,the suppression degrees of detailed features with different sensitivity levels are *** results demonstrate that this strategy can be employed to achieve precise simplification standards,thereby avoiding excessive deviations caused by arbitrary simplification and reducing the significant costs associated with trial-and-error simplification.
The paper analyzes the problem of improving the self-Timed pipeline's performance. The paper considers possible options for reducing the pipeline latency by decreasing the number of actively operating stages when ...
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The two-stage electrostatic precipitator is widely used to purify oil mist ***,there is limited research on the influences of relative humidity,particle deposition characteristics,and the generation of gaseous ***,thi...
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The two-stage electrostatic precipitator is widely used to purify oil mist ***,there is limited research on the influences of relative humidity,particle deposition characteristics,and the generation of gaseous ***,this paper established a numerical model of the electrostatic oil mist purifier and applied it to a two-stage electrostatic *** the model was used to investigate the corona discharge characteristics under different relative humidity conditions in the charged zone,the particle deposition characteristics,the purification efficiency,the ozone concentration distribution,and the oil vapor concentration distribution in the collection *** results indicate that,with a constant temperature,the corona current decreases as relative humidity increase,and there is a quadratic relationship between relative humidity and *** variation in relative humidity has little impact on the purification *** maximum ozone concentration occurs near the electrode line,and its concentration is influenced by the discharge current and inlet airflow *** oil vapor concentration reaches its maximum value at the side plates,with a value of 19 ppb,while it reaches the minimum value at the collecting zone electrode plate,with a value of 2 *** temperature is the main factor affecting the volatilization of the oil film,with higher temperatures resulting in higher oil vapor.
The development of highly efficient energy conversion technologies to extract energy from wastewater is urgently needed,especially in facing of increasing energy and environment ***,we successfully fabricated a novel ...
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The development of highly efficient energy conversion technologies to extract energy from wastewater is urgently needed,especially in facing of increasing energy and environment ***,we successfully fabricated a novel hybrid fuel cell with BiOCl-NH_(4)PTA as *** polyoxometalate(NH_(4)PTA)act as the acceptor of photoelectrons and could retard the recombination of photogenerated electrons and holes,which lead to superior photocatalytic *** utilizing BiOCl-NH_(4)PTA as photocatalysts and Pt/C air-cathode,we successfully constructed an electron and mass transfer enhanced photocatalytic hybrid fuel cell with flow-through field(F-HFC).In this novel fuel cell,dyes and biomass could be directly degraded and stable power output could be *** 87%of dyes could be degraded in 30 min irradiation and nearly 100%removed within 90 *** current density could reach up to~267.1μA/cm^(2);with maximum power density(Pmax)of~16.2μW/cm^(2) with Rhodamine B as organic pollutant in *** power densities were 9.0μW/cm^(2),12.2μW/cm^(2),and 13.9μW/cm^(2) when using methyl orange(MO),glucose and starch as substrates,*** hybrid fuel cell with BiOCl-NH_(4)PTA composite fulfills the purpose of decontamination of aqueous organic pollutants and synchronous electricity ***,the novel design cell with separated photodegradation unit and the electricity generation unit could bring potential practical application in water purification and energy recovery from wastewater.
A state-constrained optimal control problem is examined whose data depends on the time variable t. It is assumed that the dependence on the time-variable is measurable. Under the additional hypothesis that the control...
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Abstract: The paper deals with the numerical solution of fractional differential equations withinterval parameters in terms of derivatives describing anomalous diffusion *** algorithms for solving initial–boundary va...
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This paper proposes a finite-time stable chattering-free output feedback control method for rigid satellites equipped with single gimbal control moment gyro (SGCMG) actuators, considering dynamic uncertainties and ext...
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Soil aggregate stability is a fundamental measure for evaluating soil *** numerous tests exist for assessing soil aggregate stability,ultrasonic agitation(UA)is widely recognized for its ***,a significant limitation o...
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Soil aggregate stability is a fundamental measure for evaluating soil *** numerous tests exist for assessing soil aggregate stability,ultrasonic agitation(UA)is widely recognized for its ***,a significant limitation of UA is the lack of standardized methodologies and stability assessment criteria,resulting in inconsistency and incomparability across *** critical factors influence the assessment of soil aggregate stability,including sample preparation(e.g.,drying,sieving,and settling duration),initial and final aggregate size classes,the definition of final energy form and its calculation,variations in instrumentation and laboratory procedures,and the absence of standardized *** some stability methods,UA produces a broad range of results,with dispersion energy varying significantly(0.5–13440 J g^(-1))across different soil and aggregate types due to divergent procedural *** settings encompass factors such as initial power and amplitude,temperature fluctuation,soil/water ratio,probe specification(diameter and insertion depth),and the choice of liquid used during the ***,UA faces challenges related to limited reproducibility,raising doubts about its status as a standard stability assessment *** address these issues,standardization through predefined procedures and stability criteria has the potential to transform UA into a precise and widely accepted method for both qualitative and quantitative assessments of soil *** this comprehensive review,we outline the challenges in standardizing UA,elucidate the factors contributing to dispersion energy variation,and offer practical recommendations to establish standardized protocols for UA in soil aggregate stability assessments.
Prior research has consistently demonstrated that urban economic and social systems adhere to the empirical scaling ***,a plethora of evidence,including the scale-free networks of energy metabolism,the allometric grow...
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Prior research has consistently demonstrated that urban economic and social systems adhere to the empirical scaling ***,a plethora of evidence,including the scale-free networks of energy metabolism,the allometric growth patterns of species and populations,and the scaling law relationship between exergy and transformity in biosphere systems across various levels,indicates that urban ecosystems exhibit multi-level scaling law characteristics in energy metabolism under self-organization,alongside significant human activity *** study synthesizes these findings to hypothesize that urban ecological components are also aligned with system-level scaling theory within the urban metabolism *** encompasses:1)the existence of multistable coexistence and mutual transformation phenomena,mirroring the dynamic nature of scaling laws;and 2)a nuanced balance between the ecosystem and the socio-economic system,particularly in the realms of spatial competition and output *** ecosystem scaling theory hypotheses of urban metabolic processes offer a theoretical foundation for identifying ecological security tipping points,which are pivotal in the strategic decision-making for ecological planning and management in the future.
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