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1.
2.
Reliability based criteria are quite popular for optimal sensor network design. We present a modified definition of system reliability for sensor network design for two applications: reliable estimation of variables in a steady state linear flow process, and reliable fault detection and diagnosis for any process. Unlike the weakest-link based definition of system reliability in the literature, the proposed definition considers the entire system and is consistent with the reliability concept used in classical reliability literature. For each application, dual approaches for defining system reliability are proposed, and their analogy with the reliability problem in the classical reliability literature is established. Using examples and stochastic simulations, the advantage of using the proposed system reliability in contrast to the existing definition is illustrated. Part II of this series of articles presents methods for efficient generation of the system reliability function and its use in optimization-based approaches for designing optimal sensor networks. 相似文献
3.
Facial Expression Recognition (FER) is an important subject of human–computer interaction and has long been a research area of great interest. Accurate Facial Expression Sequence Interception (FESI) and discriminative expression feature extraction are two enormous challenges for the video-based FER. This paper proposes a framework of FER for the intercepted video sequences by using feature point movement trend and feature block texture variation. Firstly, the feature points are marked by Active Appearance Model (AAM) and the most representative 24 of them are selected. Secondly, facial expression sequence is intercepted from the face video by determining two key frames whose emotional intensities are minimum and maximum, respectively. Thirdly, the trend curve which represents the Euclidean distance variations between any two selected feature points is fitted, and the slopes of specific points on the trend curve are calculated. Finally, combining Slope Set which is composed by the calculated slopes with the proposed Feature Block Texture Difference (FBTD) which refers to the texture variation of facial patch, the final expressional feature are formed and inputted to One-dimensional Convolution Neural Network (1DCNN) for FER. Five experiments are conducted in this research, and three average FER rates 95.2%, 96.5%, and 97% for Beihang University (BHU) facial expression database, MMI facial expression database, and the combination of two databases, respectively, have shown the significant advantages of the proposed method over the existing ones. 相似文献
4.
ULK1 (unc-51 like autophagy activating kinase 1), a mammalian serine/threonine kinase, is a key component of
autophagy initiation complex and helps to induce all types of autophagy. Canonical autophagy is a process in which,
through the interactions of a series of autophagy-related proteins, damaged organelles or misfolded proteins are
engulfed by autophagosomes and then merged with lysosomes to be degraded. Thus, canonical autophagy is an
important constituent part of the cellular “quality control.” Besides, accumulating evidence indicates that ULK1 exerts
autophagy-independent effects in a cell-specific manner. For example, ULK1 facilitates neurite elongation through the
regulation of endoplasmic reticulum (ER)–Golgi trafficking in neurons, stimulates phosphopentose pathway to help
NADPH (nicotinamide adenine dinucleotide phosphate hydrogen) production, and acts as a duplex regulator in type
I IFN (type I interferon) induced innate immune response. Considering the importance and diversity of ULK1 in
various biological processes, this review aims to present a comprehensive overview of autophagy and non-autophagy
related functions of ULK1 in a variety of human physiological, pathological, and disease processes. 相似文献
5.
Sebastian Sjoqvist Kentaro Otake Yoshihiko Hirozane 《International journal of molecular sciences》2020,21(24)
There is a lack of reliable biomarkers for disorders of the central nervous system (CNS), and diagnostics still heavily rely on symptoms that are both subjective and difficult to quantify. The cerebrospinal fluid (CSF) is a promising source of biomarkers due to its close connection to the CNS. Extracellular vesicles are actively secreted by cells, and proteomic analysis of CSF extracellular vesicles (EVs) and their molecular composition likely reflects changes in the CNS to a higher extent compared with total CSF, especially in the case of neuroinflammation, which could increase blood–brain barrier permeability and cause an influx of plasma proteins into the CSF. We used proximity extension assay for proteomic analysis due to its high sensitivity. We believe that this methodology could be useful for de novo biomarker discovery for several CNS diseases. We compared four commercially available kits for EV isolation: MagCapture and ExoIntact (based on magnetic beads), EVSecond L70 (size-exclusion chromatography), and exoEasy (membrane affinity). The isolated EVs were characterized by nanoparticle tracking analysis, ELISA (CD63, CD81 and albumin), and proximity extension assay (PEA) using two different panels, each consisting of 92 markers. The exoEasy samples did not pass the built-in quality controls and were excluded from downstream analysis. The number of detectable proteins in the ExoIntact samples was considerably higher (~150% for the cardiovascular III panel and ~320% for the cell regulation panel) compared with other groups. ExoIntact also showed the highest intersample correlation with an average Pearson’s correlation coefficient of 0.991 compared with 0.985 and 0.927 for MagCapture and EVSecond, respectively. The median coefficient of variation was 5%, 8%, and 22% for ExoIntact, MagCapture, and EVSecond, respectively. Comparing total CSF and ExoIntact samples revealed 70 differentially expressed proteins in the cardiovascular III panel and 17 in the cell regulation panel. To our knowledge, this is the first time that CSF EVs were analyzed by PEA. In conclusion, analysis of CSF EVs by PEA is feasible, and different isolation kits give distinct results, with ExoIntact showing the highest number of identified proteins with the lowest variability. 相似文献
6.
Amer Ibrahim Al-Omari Ibrahim M. Almanjahie Amal S. Hassan Heba F. Nagy 《计算机、材料和连续体(英文)》2020,64(2):835-857
In reliability analysis, the stress-strength model is often used to describe the life of
a component which has a random strength (X) and is subjected to a random stress (Y). In this
paper, we considered the problem of estimating the reliability R=P [Y<X] when the
distributions of both stress and strength are independent and follow exponentiated Pareto
distribution. The maximum likelihood estimator of the stress strength reliability is calculated
under simple random sample, ranked set sampling and median ranked set sampling methods.
Four different reliability estimators under median ranked set sampling are derived. Two
estimators are obtained when both strength and stress have an odd or an even set size. The
two other estimators are obtained when the strength has an odd size and the stress has an
even set size and vice versa. The performances of the suggested estimators are compared
with their competitors under simple random sample via a simulation study. The simulation
study revealed that the stress strength reliability estimates based on ranked set sampling and
median ranked set sampling are more efficient than their competitors via simple random
sample. In general, the stress strength reliability estimates based on median ranked set
sampling are smaller than the corresponding estimates under ranked set sampling and simple
random sample methods. 相似文献
7.
The veracity present in molecular data available in biological databases possesses new challenges for data analytics. The analysis of molecular data of various diseases can provide vital information for developing better understanding of the molecular mechanism of a disease. In this paper, an attempt has been made to propose a model that addresses the issue of veracity in data analytics for amino acid association patterns in protein sequences of Swine Influenza Virus. The veracity is caused by intra-sequential and inter-sequential biases present in the sequences due to varying degrees of relationships among amino acids. A complete dataset of 63,682 protein sequences is downloaded from NCBI and is refined. The refined dataset consists of 26,594 sequences which are employed in the present study. The type I fuzzy set is employed to explore amino acid association patterns in the dataset. The type I fuzzy support is refined to partially remove the inter-sequential biases causing veracity in data. The remaining inter-sequential biases present in refined fuzzy support are evaluated and eliminated using type II fuzzy set. Hence, it is concluded that a combination of type II fuzzy & refined fuzzy approach is the optimal approach for extracting a better picture of amino acid association patterns in the molecular dataset. 相似文献
8.
李传峰 《电信工程技术与标准化》2006,19(10):20-23
无线承载测试的应用取决于UE上行、下行无线接入能力以及UE支持的电信业务和承载业务.不同的电信业务和承载业务需要不同无线承载.对无线承载配置统一规定,确保了UE和不同网络之间的互操作性,解决了UE和不同网络之间的网络兼容性问题.无线接入承载测试就是来验证UE在建立业务时是否对应规定的无线承载. 相似文献
9.
10.
A Lattice Approach to Image Segmentation 总被引:1,自引:0,他引:1
Jean Serra 《Journal of Mathematical Imaging and Vision》2006,24(1):83-130
After a formal definition of segmentation as the largest partition of the space according to a criterion σ and a function
f, the notion of a morphological connection is reminded. It is used as an input to a central theorem of the paper (Theorem
8), that identifies segmentation with the connections that are based on connective criteria. Just as connections, the segmentations can then
be regrouped by suprema and infima. The generality of the theorem makes it valid for functions from any space to any other
one. Two propositions make precise the AND and OR combinations of connective criteria.
The soundness of the approach is demonstrated by listing a series of segmentation techniques. One considers first the cases
when the segmentation under study does not involve initial seeds. Various modes of regularity are discussed, which all derive
from Lipschitz functions. A second category of examples involves the presence of seeds around which the partition of the space
is organized. An overall proposition shows that these examples are a matter for the central theorem. Watershed and jump connection
based segmentations illustrate this type of situation. The third and last category of examples deals with cases when the segmentation
occurs in an indirect space, such as an histogram, and is then projected back on the actual space under study.
The relationships between filtering and segmentation are then investigated. A theoretical chapter introduces and studies the
two notions of a pulse opening and of a connected operator. The conditions under which a family of pulse openings can yield a connected filter are clarified. The ability of segmentations
to generate pyramids, or hierarchies, is analyzed. A distinction is made between weak hierarchies where the partitions increase
when going up in the pyramid, and the strong hierarchies where the various levels are structured as semi-groups, and particularly
as granulometric semi-groups.
The last section is based on one example, and goes back over the controversy about “lattice” versus “functional” optimization.
The problem is now tackled via a case of colour segmentation, where the saturation serves as a cursor between luminance and
hue. The emphasis is put on the difficulty of grouping the various necessary optimizations into a single one. 相似文献