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1.
The probabilistic learning on manifolds (PLoM) introduced in 2016 has solved difficult supervised problems for the “small data” limit where the number N of points in the training set is small. Many extensions have since been proposed, making it possible to deal with increasingly complex cases. However, the performance limit has been observed and explained for applications for which N is very small and for which the dimension of the diffusion-map basis is close to N. For these cases, we propose a novel extension based on the introduction of a partition in independent random vectors. We take advantage of this development to present improvements of the PLoM such as a simplified algorithm for constructing the diffusion-map basis and a new mathematical result for quantifying the concentration of the probability measure in terms of a probability upper bound. The analysis of the efficiency of this extension is presented through two applications.  相似文献   
2.

Improving the properties of laminated veneer lumber (LVL) through wood modification expands its usage as building material, especially for outdoor applications. The outdoor performance of LVL products needs to be tested against different biotic agents, and methods are needed for testing and evaluating their effect on the structural integrity of LVL. In this study, drilling resistance (DR) measurements were used to quantify the effect of fungal decay in phenol-formaldehyde (PF) resin treated European beech (Fagus sylvatica L.) LVL caused by white rot fungi. Material specific peculiarities and their effect on the evaluation method were studied such as the effect of drill bit blunting, moisture content (MC), drilling direction and PF resin content on the DR of PF-modified LVL. The drilling direction in relation to veneer and glue layers had a significant effect on DR and feeding resistance (FR). The PF resin treatment increased the DR. Feeding resistance was found more sensitive to the blunting of the drill bit than DR. The effect of MC on DR and FR was found to be insignificant. The effect of PF resin content on the prediction of mass loss (ML) by DR became prominent only for ML by white rot decay below 10 %. Correlations between DR, ML due to fungal decay and weight percent gain were established and described with a two-factor regression model. The drill bit feed rate of 0.5 m min?1 and the rotational frequency of 3500 min?1 as well as the transversal drilling in relation to the veneer (glue) layers were recommended for the assessment of beech LVL treated with PF resin. The DR measurements showed high potential as a fast standard evaluation method for decay and strength loss of LVL products.

  相似文献   
3.
Moeck  Christian  Merk  Markus  Radny  Dirk  Auckenthaler  Adrian  Schirmer  Mario  Gabriel  Thomas 《Grundwasser》2022,27(3):187-196
Grundwasser - Eine nachhaltige Wasserversorgung in urbanen Gebieten stellt aufgrund des Nutzungsdrucks sowie vielfältiger anthropogener Einträge eine große Herausforderung dar....  相似文献   
4.
A consecutive competitive gas-liquid reaction is investigated using a Taylor bubble setup regarding the influence of fluid mixing in the bubble wake on yield and selectivity. The concentration fields behind a Taylor bubble are visualized and measured quantitatively with a novel time-resolved absorption imaging technique based on Beer Lamberts law and an integral selectivity is derived. In addition, the calculation of the local selectivity, often used in numerical approaches, is discussed and the existing experimental limits for its derivation are pointed out. Finally, an increase in selectivity of a competitive consecutive reaction for enhanced mixing is experimentally confirmed.  相似文献   
5.
The anoctamin (TMEM16) family of transmembrane protein consists of ten members in vertebrates, which act as Ca2+-dependent ion channels and/or Ca2+-dependent scramblases. ANO4 which is primarily expressed in the CNS and certain endocrine glands, has been associated with various neuronal disorders. Therefore, we focused our study on prioritizing missense mutations that are assumed to alter the structure and stability of ANO4 protein. We employed a wide array of evolution and structure based in silico prediction methods to identify potentially deleterious missense mutations in the ANO4 gene. Identified pathogenic mutations were then mapped to the modeled human ANO4 structure and the effects of missense mutations were studied on the atomic level using molecular dynamics simulations. Our data show that the G80A and A500T mutations significantly alter the stability of the mutant proteins, thus providing new perspective on the role of missense mutations in ANO4 gene. Results obtained in this study may help to identify disease associated mutations which affect ANO4 protein structure and function and might facilitate future functional characterization of ANO4.  相似文献   
6.
Demands on production, distribution and consumption of electrical energy change fundamentally with the energy revolution. Energy purchasing costs for inflexible consumers are rising and proceeds of inflexible producers are sinking. Companies are able to reduce costs by marketing operational flexibility options. This article sets out the need of flexibility in the energy system and the new marketing options. Flexibility potentials within infrastructure plants of a chemical park are analyzed, evaluated regarding marketing and activated in the presented research project FlexChemistry.  相似文献   
7.
Root architecture and growth are decisive for crop performance and yield, and thus a highly topical research field in plant sciences. The root system of the model plant Arabidopsis thaliana is the ideal system to obtain insights into fundamental key parameters and molecular players involved in underlying regulatory circuits of root growth, particularly in responses to environmental stimuli. Root gravitropism, directional growth along the gravity, in particular represents a highly sensitive readout, suitable to study adjustments in polar auxin transport and to identify molecular determinants involved. This review strives to summarize and give an overview into the function of PIN-FORMED auxin transport proteins, emphasizing on their sorting and polarity control. As there already is an abundance of information, the focus lies in integrating this wealth of information on mechanisms and pathways. This overview of a highly dynamic and complex field highlights recent developments in understanding the role of auxin in higher plants. Specifically, it exemplifies, how analysis of a single, defined growth response contributes to our understanding of basic cellular processes in general.  相似文献   
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正炼油厂比以往任何时候都需要充分利用资产。顾问给出的行业基准对于通盘考量是有价值的-但是如何在工厂层面上推出真正的改进?往复压缩机可能是合适的选择。作为炼油厂氢供应的关键,压缩机在性能和可靠性方面有很大的改进空间。作为炼油厂资本设备的主要项目,维护成本与重置价值的比率从2.5%下降至1.5%是值得庆祝的。新方法可以对往复压缩机的性能进行基准测试和改进,这样的结果在大多数设施中是完全可以实现的。  相似文献   
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