Journal articles on the topic 'Matrix-based descriptions'
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SUNDBERG, PER, ALEXEY V. CHERNYSHEV, HIROSHI KAJIHARA, TOBIAS KÅNNEBY, and MALIN STRAND. "Character-matrix based descriptions of two new nemertean (Nemertea) species." Zoological Journal of the Linnean Society 157, no. 2 (October 2009): 264–94. http://dx.doi.org/10.1111/j.1096-3642.2008.00514.x.
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Liu, Caihui, Kecan Cai, Duoqian Miao, and Jin Qian. "Novel matrix-based approaches to computing minimal and maximal descriptions in covering-based rough sets." Information Sciences 539 (October 2020): 312–26. http://dx.doi.org/10.1016/j.ins.2020.06.022.
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Divya, R., and S. Angel Latha Mary. "Ontology based search result optimisation using singular matrix." International Journal of Engineering & Technology 7, no. 1.3 (December 31, 2017): 33. http://dx.doi.org/10.14419/ijet.v7i1.3.8983.
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In recent era, today a many firms share their service/product descriptions. With that, many meaningful information in the textual form is hidden under the unstructured text. Algorithms like information extraction enable the identification of structured relations and they does not produce an optimal result and it is much costlier to operate with headlines of a text which has no examples of the target structured information. We propose a new approach which facilitates the formation of a structured metadata by recognizing documents which are likely to have some type and this information is to be subsequently used for both segregation and search process. Our approach is based on an idea that some attributes of a text will match with the query object which acts as identifier both for segregation as well as for storage and retrieval. Our implementation results show that our approach provides some superior results than existing approaches which rely only on query content or on textual information, to discover the key attributes.
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Mitchell, Herschel L., P. L. Houtekamer, and Sylvain Heilliette. "Impact of AMSU-A Radiances in a Column Ensemble Kalman Filter." Monthly Weather Review 146, no. 12 (November 6, 2018): 3949–76. http://dx.doi.org/10.1175/mwr-d-18-0093.1.
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Abstract A column EnKF, based on the Canadian global EnKF and using the RTTOV radiative transfer (RT) model, is employed to investigate issues relating to the EnKF assimilation of Advanced Microwave Sounding Unit-A (AMSU-A) radiance measurements. Experiments are performed with large and small ensembles, with and without localization. Three different descriptions of background temperature error are considered: 1) using analytical vertical modes and hypothetical spectra, 2) using the vertical modes and spectrum of a covariance matrix obtained from the global EnKF after 2 weeks of cycling, and 3) using the vertical modes and spectrum of the static background error covariance matrix employed to initiate a global data assimilation cycle. It is found that the EnKF performs well in some of the experiments with background error description 1, and yields modest error reductions with background error description 3. However, the EnKF is virtually unable to reduce the background error (even when using a large ensemble) with background error description 2. To analyze these results, the different background error descriptions are viewed through the prism of the RT model by comparing the trace of the matrix , where is the RT model and is the background error covariance matrix. Indeed, this comparison is found to explain the difference in the results obtained, which relates to the degree to which deep modes are, or are not, present in the different background error covariances. The results suggest that, after 2 weeks of cycling, the global EnKF has virtually eliminated all background error structures that can be “seen” by the AMSU-A radiances.
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DAS, ASHOK, and U. SALEEM. "DARBOUX TRANSFORMATION AND MULTI-SOLITON SOLUTIONS OF TWO-BOSON HIERARCHY." Modern Physics Letters A 26, no. 09 (March 21, 2011): 625–36. http://dx.doi.org/10.1142/s0217732311035249.
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We study Darboux transformations for the two boson (TB) hierarchy both in the scalar as well as in the matrix descriptions of the linear equation. While Darboux transformations have been extensively studied for integrable models based on SL (2, R) within the AKNS framework, this model is based on SL (2, R)⊗ U (1). The connection between the scalar and the matrix descriptions in this case implies that the generic Darboux matrix for the TB hierarchy has a different structure from that in the models based on SL (2, R) studied thus far. The conventional Darboux transformation is shown to be quite restricted in this model. We construct a modified Darboux transformation which has a much richer structure and which also allows for multi-soliton solutions to be written in terms of Wronskians. Using the modified Darboux transformations, we explicitly construct one-soliton/kink solutions for the model.
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Wang, Jingqian, and Xiaohong Zhang. "Matrix approaches for some issues about minimal and maximal descriptions in covering-based rough sets." International Journal of Approximate Reasoning 104 (January 2019): 126–43. http://dx.doi.org/10.1016/j.ijar.2018.10.021.
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Novoselova, Olga, and Anton Sidorov. "Integration of Descriptions of Static Structures at Automation of Design Tasks." MATEC Web of Conferences 346 (2021): 03065. http://dx.doi.org/10.1051/matecconf/202134603065.
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This paper investigates the process of integrating descriptions of static structures in the form of charts and specifications at the stage of conceptual modeling of automated systems, that are developed to solve design tasks. In the process of creating an automated system based on the methodology for automating intellectual labor (MAIL), models of design tasks are formed: initial, conceptual, infological and datalogical. The conceptual model describes the system of concepts of the subject area. The description of conceptual model representation includes specifications and charts: for a static component - F1 and F2, the chart of conceptual structure; for a dynamic component - F3 and F4, the chart depicting a system of subject dependences; F6 and the matrix chart showing the model as a whole including static and dynamic components coordination. The features of constructing diagrams and forming specifications in the formation of a conceptual structure are studied, on the basis of which the method and technique to integrate descriptions of static components for the system of concepts of the subject area are determined. The article is given the integration of descriptions in the form of diagrams and specifications for the static components of conceptual model representations.
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Wasserscheidt, Philipp. "Explaining Code-Switching. Matrix Language Models vs. Bilingual Construction Grammar." Književni jezik, no. 31 (December 2020): 57–87. http://dx.doi.org/10.33669/kj2020-31-04.
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This paper challenges the concept of matrix, base or basic language used in many descriptions and models of insertional code-switching. It proposes an account based on Construction Grammar and usage-based principles. At the heart of the paper is a discussion of four problematic issues of matrix-language approaches: the unitary conception of the notion of language, the generalization that syntactic frames mirror languages, the missing independent evidence for a matrix language and the narrow scope of the models that employ this term. The proposed approach of Bilingual Construction Grammar instead operates with a more complex, usage-based concept of language affiliation and places constructions in the centre of speech production. It thus avoids too coarse global predictions in favour of construction-specific predictions. This way, the matrix-language effect can be reinterpreted as by-product of constructional processing. Instead of using the term matrix language it is thus more appropriate to speak of matrix constructions.
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Smith, Aaron, Rebecca Dornburg, and Quentin Wheeler. "Larvae of the genus Eleodes (Coleoptera, Tenebrionidae): matrix-based descriptions, cladistic analysis, and key to late instars." ZooKeys 415 (June 12, 2014): 217–68. http://dx.doi.org/10.3897/zookeys.415.5887.
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Bo¨hm, H. J., F. G. Rammerstorfer, F. D. Fischer, and T. Siegmund. "Microscale Arrangement Effects on the Thermomechanical Behavior of Advanced Two-Phase Materials." Journal of Engineering Materials and Technology 116, no. 3 (July 1, 1994): 268–73. http://dx.doi.org/10.1115/1.2904285.
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Finite Element based micromechanical methods are used to study the influence of microscale phase arrangements on the overall and microscale thermomechanical properties of two advanced two-phase materials, duplex steels and unidirectional continuously reinforced metal matrix composites (MMCs). Both inclusion-matrix topologies and interwoven microgeometries are investigated for duplex steels, and the predicted macroscopic transverse elastoplastic responses are correlated with quantitative stereological descriptions of the microgeometries. For the MMCs, the emphasis is put on the influence of the fiber arrangement on the microscale residual stress states of the as-produced material and on their effects on damage mechanisms.
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VALENTIN, D., H. ABDI, and A. J. O’TOOLE. "CATEGORIZATION AND IDENTIFICATION OF HUMAN FACE IMAGES BY NEURAL NETWORKS: A REVIEW OF THE LINEAR AUTOASSOCIATIVE AND PRINCIPAL COMPONENT APPROACHES." Journal of Biological Systems 02, no. 03 (September 1994): 413–29. http://dx.doi.org/10.1142/s0218339094000258.
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Recent statistical/neural network models of face processing suggest that faces can be efficiently represented in terms of the eigendecomposition of a matrix storing pixel-based descriptions of a set of face images. The studies presented here support the idea that the information useful for solving seemingly complex tasks such as face categorization or identification can be described using simple linear models (linear autoassociator or principal component analysis) in conjunction with a pixel-based coding of the faces.
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Lyachek, Yuliy. "An Efficient Method for Forming Parabolic Curves and Surfaces." Mathematics 8, no. 4 (April 15, 2020): 592. http://dx.doi.org/10.3390/math8040592.
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A new method for the formation of parabolic curves and surfaces is proposed. It does not impose restrictions on the relative positions in space of the sequence of reference points relative to each other, meaning it compares favorably with other prototypes. The disadvantages of the Overhauser and Brever–Anderson methods are noted. The method allows one to effectively form and edit curves and surfaces when changing the coordinates of any given point. This positive effect is achieved due to the appropriate choice of local coordinate systems for the mathematical description of each parabola, which together define a composite interpolation curve or surface. The paper provides a detailed mathematical description of the method of parabolic interpolation of curves and surfaces based on the use of matrix calculations. Analytical descriptions of a composite parabolic curve and its first and second derivatives are given, and continuity analysis of these factors is carried out. For the matrix of points of the defining polyhedron, expressions are presented that describe the corresponding surfaces, as well as the unit normal at any point. The comparative table of the required number of pseudo-codes for calculating the coordinates of one point for constructing a parabolic curve for the three methods is given.
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Bahar, Asnul, Harun Ates, Maged H. Al-Deeb, Salem El Abd Salem, Hussein S. Badaam, Steef J. Linthorst, and Mohan G. Kelkar. "An Innovative Approach To Integrate Fracture, Well Test and Production Data into Reservoir Models." SPE Reservoir Evaluation & Engineering 8, no. 04 (August 1, 2005): 325–36. http://dx.doi.org/10.2118/84876-pa.
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Summary This paper presents an innovative approach to integrate fracture, well-test, and production data into the static description of a reservoir model as an input to the flow simulation. The approach has been implemented successfully in a field study of a giant naturally fractured carbonate reservoir in the Middle East. This study was part of a full-field integrated reservoir-characterization and flow-simulation project. The main input available for this work includes matrix properties and fracture-network, well-test, and production data. Stochastic models of matrix properties were generated using a geostatistical methodology based on well logs, core, seismic data, and geological interpretation. The fracture network was described in the reservoir as lineaments (fracture swarms) showing two major fracture trends. The network and its properties (i.e., fracture porosities and permeabilities) were generated by reconciling seismic, well-log, and dynamic data (Well Test and Production Log Tool, PLT). The challenge of the study is to integrate all the input in an efficient and practical way to produce a consistent model between static and dynamic data. As a result, it is expected to reduce the history-matching effort. This challenge was solved by an innovative iterative procedure between the static and dynamic models. The static part consists of the calibration of model permeability to match the well-test permeability. It is done by comparing their flow potentials, kh. In this analysis, the dominant factor in controlling production at each well, either matrix or fracture, was determined. Based on the dominant factor, matrix or fracture permeability was modified accordingly. This way, the changes in permeability are consistent with the geological understanding of the field. The dynamic part was carried out through a full-field flow simulation to integrate production data. The flow simulation at this stage was used to match production capacity, [i.e., to determine whether the given permeability (matrix and fracture) distribution is enough to produce the fluid at the specified pressure during the producing period of the well]. The iteration is stopped once a reasonable production-capacity match is obtained. In general, a good match was achieved within three to four iterations. The generated reservoir description is expected to substantially reduce the effort required to obtain a good history match. Introduction This paper presents the approach, implementation, and results of a fracture-integration process into a reservoir model. The study is part of a fully integrated reservoir-characterization and flow-simulation study of an oilfield in the Middle East. A comprehensive integrated reservoir characterization was conducted by considering all available data, namely well logs and cores, geological interpretation, seismic (structures and inversion-derived porosity), fracture network, and pressure-buildup (PBU) tests. The approach used in the study was a stochastic approach in which multiple reservoir descriptions were generated to quantify the uncertainty in future performance. Reservoir properties for each realization were generated with a geostatistical technique that produces properties (i.e., porosity, permeability, and water saturation) consistent with the underlying rock-type description. The description was based on core and log data. Additionally, porosity, which affects the permeability description, was also constrained to the seismic-derived porosity. The permeability distribution generated by this method is referred to as the core-derived permeability in this paper. Because core measurement commonly represents the matrix property of the rock, the core-derived permeability mentioned above was also referred to as matrix permeability. It is commonly observed that the well-test permeability values do not match the thickness-weighted core-permeability averages. This is partly because of the differences in the measurement scales of core samples, which cover a few inches, and well tests, which investigate several hundred feet around the wellbore. In addition, the presence of fractures and/or high-permeability channels will further enhance the difference between the two sources of data. The mismatch between these two permeabilities may be small or as high as three orders of magnitude. Therefore, reservoir descriptions based on core measurements alone cannot honor the well-test results and need to be modified properly.
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Huan, Zhan, Chang Wei, and Guang-Hui Li. "Outlier Detection in Wireless Sensor Networks Using Model Selection-Based Support Vector Data Descriptions." Sensors 18, no. 12 (December 7, 2018): 4328. http://dx.doi.org/10.3390/s18124328.
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Wireless sensor networks (WSNs) are often deployed in harsh and unattended environments, which may cause the generation of abnormal or low quality data. The inaccurate and unreliable sensor data may increase generation of false alarms and erroneous decisions, so it’s very important to detect outliers in sensor data efficiently and accurately to ensure sound scientific decision-making. In this paper, an outlier detection algorithm (TSVDD) using model selection-based support vector data description (SVDD) is proposed. Firstly, the Toeplitz matrix random feature mapping is used to reduce the time and space complexity of outlier detection. Secondly, a novel model selection strategy is realized to keep the algorithm stable under the low feature dimensions, this strategy can select a relatively optimal decision model and avoid both under-fitting and overfitting phenomena. The simulation results on SensorScope and IBRL datasets demonstrate that, TSVDD achieves higher accuracy and lower time complexity for outlier detection in WSNs compared with existing methods.
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Puka, Agnes Ona Bliti. "ANALISIS KEMAMPUAN PEMAHAMAN KONSEP MATEMATIKA PADA KELAS XI BUDAYA DI SMAK St. FRANSISKUS ASISI LARANTUKA." Jurnal Penelitian Pendidikan Matematika Sumba 3, no. 1 (September 17, 2021): 12–23. http://dx.doi.org/10.53395/jppms.v3i1.238.
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The purpose of this study is to determine the ability to understand the mathematical concept of students of class XI Culture SMAK St. Francis of Assisi Larantuka. The data are collected by the results of students’ ability test in understanding of mathematical concepts and unstructured interviews. The test questions used to measure students’ abilities in understanding mathematical concepts consist of 2 questions in the form of descriptions with matrix transpose material and matrix multiplication. The test results are analysed based on indicators of mathematical understanding, namely: 1) the ability to explain a definition in their own words according to essential traits/characteristics, 2) the ability to make examples in mathematical concepts, 3) the ability to use concepts in solving problems. Population in this study are students on eleventh culture class of SMAK St. Francis of Assisi Larantuka with two sample of students. The results show that there are the differences in the ability to understand mathematical concepts between students through Problem Based Learning.Keywords: Mathematical concepts understanding, Problem Based Learning, matrix.
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Lahoche, Vincent, Mohamed Ouerfelli, Dine Ousmane Samary, and Mohamed Tamaazousti. "Field Theoretical Approach for Signal Detection in Nearly Continuous Positive Spectra II: Tensorial Data." Entropy 23, no. 7 (June 23, 2021): 795. http://dx.doi.org/10.3390/e23070795.
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The tensorial principal component analysis is a generalization of ordinary principal component analysis focusing on data which are suitably described by tensors rather than matrices. This paper aims at giving the nonperturbative renormalization group formalism, based on a slight generalization of the covariance matrix, to investigate signal detection for the difficult issue of nearly continuous spectra. Renormalization group allows constructing an effective description keeping only relevant features in the low “energy” (i.e., large eigenvalues) limit and thus providing universal descriptions allowing to associate the presence of the signal with objectives and computable quantities. Among them, in this paper, we focus on the vacuum expectation value. We exhibit experimental evidence in favor of a connection between symmetry breaking and the existence of an intrinsic detection threshold, in agreement with our conclusions for matrices, providing a new step in the direction of a universal statement.
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Nixon, Wilfrid A., and Lin Qiu. "Developing a Storm Severity Index." Transportation Research Record: Journal of the Transportation Research Board 1911, no. 1 (January 2005): 143–48. http://dx.doi.org/10.1177/0361198105191100114.
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A primary goal in winter highway maintenance is to develop various maintenance processes so that quality control can be measured. If actions can be measured, they can be improved. A difficulty with this approach is that winter maintenance addresses the impacts of winter weather on the transportation system and that weather is inherently uncontrollable. Consequently, for a quality process to be applied to winter maintenance, the severity of individual storms must be assessed. This paper presents one way in which the severity of a storm can be measured, specifically by an index. The first step in developing an index for individual storms is to develop a method of describing storms. The method here describes storms by using six factors, including prestorm and poststorm conditions and temperatures, wind speed, and precipitation type. The matrix created is a refinement of that presented in FHWA's manual of practice for effective anti-icing. With the use of a simplified variation of this matrix-based description of storms (more than 250 descriptions), a score is generated for each storm type. This score is then adjusted so that scores for all storms fall into a normal distribution between 0 and 1. This ranking of storms was evaluated by winter maintenance garage supervisors at the Iowa Department of Transportation. Supervisors were asked to rank 10 storms (presented as brief written descriptions) from easiest to hardest to handle. Results were compared with those of the initial storm severity index. From that comparison, numerical values for certain factors were adjusted so that storm severity index scores for these 10 storms agreed with rankings given by the garage supervisors.
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KIM, YANGJIN, MAGDALENA A. STOLARSKA, and HANS G. OTHMER. "A HYBRID MODEL FOR TUMOR SPHEROID GROWTH IN VITRO I: THEORETICAL DEVELOPMENT AND EARLY RESULTS." Mathematical Models and Methods in Applied Sciences 17, supp01 (November 2007): 1773–98. http://dx.doi.org/10.1142/s0218202507002479.
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Tumor spheroids grown in vitro have been widely used as models of in vivo tumor growth because they display many of the characteristics of in vivo growth, including the effects of nutrient limitations and perhaps the effect of stress on growth. In either case there are numerous biochemical and biophysical processes involved whose interactions can only be understood via a detailed mathematical model. Previous models have focused on either a continuum description or a cell-based description, but both have limitations. In this paper we propose a new mathematical model of tumor spheroid growth that incorporates both continuum and cell-level descriptions, and thereby retains the advantages of each while circumventing some of their disadvantages. In this model the cell-based description is used in the region where the majority of growth and cell division occurs, at the periphery of a tumor, while a continuum description is used for the quiescent and necrotic zones of the tumor and for the extracellular matrix. Reaction-diffusion equations describe the transport and consumption of two important nutrients, oxygen and glucose, throughout the entire domain. The cell-based component of this hybrid model allows us to examine the effects of cell–cell adhesion and variable growth rates at the cellular level rather than at the continuum level. We show that the model can predict a number of cellular behaviors that have been observed experimentally.
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Miller, R. H. "Dimensionality of Stable and Unstable Directions in the Gravitational N—Body Problem." International Astronomical Union Colloquium 172 (1999): 139–47. http://dx.doi.org/10.1017/s0252921100072493.
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AbstractThe gravitational n—body problem is chaotic. Phase trajectories that start very near each other separate rapidly. The rate looks exponential over long times. At any instant, trajectories separated in certain directions move apart rapidly (unstable directions), while those separated in other directions stay about the same (stable directions). Unstable directions lie along eigenvectors that correspond to positive eigenvalues of the matrix of force gradients. The number of positive eigenvalues of that matrix gives the dimensionality of stable regions. This number has been studied numerically in a series of 100—body integrations. It continues to change as long as the integration continues because the matrix changes extremely rapidly. On average, there are about 1.2n unstable directions out of 3n. Issues of dimensionality arise when the tools of ergodic studies are brought to bear on the problem of trajectory separation. A method of estimating the rate of trajectory separation based on matrix descriptions is presented in this note. Severe approximations are required.
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Vlase, Sorin, and Marin Marin. "Finite Element Method-Based Dynamic Response of Micropolar Polymers with Voids." Polymers 13, no. 21 (October 28, 2021): 3727. http://dx.doi.org/10.3390/polym13213727.
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Composite-based polymer materials are manufactured in a wide variety of types with different compositions, structures, geometries, and topological descriptions. Among these, micropolar materials with voids have become increasingly studied in the literature. This paper establishes the equations of motion for such a material for the purpose of dynamic analysis via the finite element method (FEM). The Euler–Lagrangian formalism, based on the expressions of kinetic energy, potential energy, and mechanical work, is used. Hence, it is possible to study the dynamic response of such a system in the most general configuration case. The choice of the shape functions will determine the matrix coefficients for each particular case. An application illustrates the presented results.
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Gupta, Meenu, Hao Wu, Simrann Arora, Akash Gupta, Gopal Chaudhary, and Qiaozhi Hua. "Gene Mutation Classification through Text Evidence Facilitating Cancer Tumour Detection." Journal of Healthcare Engineering 2021 (July 27, 2021): 1–16. http://dx.doi.org/10.1155/2021/8689873.
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A cancer tumour consists of thousands of genetic mutations. Even after advancement in technology, the task of distinguishing genetic mutations, which act as driver for the growth of tumour with passengers (Neutral Genetic Mutations), is still being done manually. This is a time-consuming process where pathologists interpret every genetic mutation from the clinical evidence manually. These clinical shreds of evidence belong to a total of nine classes, but the criterion of classification is still unknown. The main aim of this research is to propose a multiclass classifier to classify the genetic mutations based on clinical evidence (i.e., the text description of these genetic mutations) using Natural Language Processing (NLP) techniques. The dataset for this research is taken from Kaggle and is provided by the Memorial Sloan Kettering Cancer Center (MSKCC). The world-class researchers and oncologists contribute the dataset. Three text transformation models, namely, CountVectorizer, TfidfVectorizer, and Word2Vec, are utilized for the conversion of text to a matrix of token counts. Three machine learning classification models, namely, Logistic Regression (LR), Random Forest (RF), and XGBoost (XGB), along with the Recurrent Neural Network (RNN) model of deep learning, are applied to the sparse matrix (keywords count representation) of text descriptions. The accuracy score of all the proposed classifiers is evaluated by using the confusion matrix. Finally, the empirical results show that the RNN model of deep learning has performed better than other proposed classifiers with the highest accuracy of 70%.
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HAO, KE, PHILLIP C.-Y. SHEU, and HIROSHI YAMAGUCHI. "SEMANTIC SEARCH OF SERVICES." International Journal of Semantic Computing 07, no. 03 (September 2013): 257–90. http://dx.doi.org/10.1142/s1793351x13500049.
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This paper addresses semantic search of Web services using natural language processing. First we survey various existing approaches, focusing on the fact that the expensive costs of current semantic annotation frameworks result in limited use of semantic search for large scale applications. We then propose a service search framework based on the vector space model to combine the traditional frequency weighted term-document matrix, the syntactical information extracted from a lexical database and a dependency grammar parser. In particular, instead of using terms as the rows in a term-document matrix, we propose using synsets from WordNet to distinguish different meanings of a word under different contexts as well as clustering different words with similar meanings. Also based on the characteristics of Web services descriptions, we propose an approach to identifying semantically important terms to adjust weightings. Our experiments show that our approach achieves its goal well.
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Arteaga, Oriol, John Freudenthal, and Bart Kahr. "Reckoning electromagnetic principles with polarimetric measurements of anisotropic optically active crystals." Journal of Applied Crystallography 45, no. 2 (March 15, 2012): 279–91. http://dx.doi.org/10.1107/s0021889812006085.
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A method is introduced to correlate electromagnetic theory and polarimetric experiments for anisotropic optically active crystals at oblique angles of incidence. It is based on the 4 × 4 algebraic descriptions of light propagation in layered anisotropic media, which can be simplified to 2 × 2 matrices when multiple reflections are disregarded. Spectroscopic Mueller matrix measurements in transmission and at oblique angles of incidence have been made on two uniaxial crystals: α-quartz and silver thiogallate. Their optical activity tensors have been spectroscopically determined using the method presented here.
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LU, Yang, Bin CAI, Daopeng QIAO, Yanming FU, and Maorui ZHANG. "Trajectory tracking control of failure satellite with actuator jumping fault." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 40, no. 2 (April 2022): 458–64. http://dx.doi.org/10.1051/jnwpu/20224020458.
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This paper studied the trajectory tracking control of a failure satellite that has actuator jumping fault. It proposed a design method based on the jumping control input for the model reference tracking controller. By comb-ining the stochastic stability definition with model reference tracking, it gave the mathematical descriptions of the trajectory tracking control of the failure satellite. It used the linear matrix inequality method and the parametric solution method of the nonhomogeneous generalized Sylvester matrix equation to design the robust H∞ state feedback control law and the complete parametric feed-forward tracking compensator respectively, with the disturbance of the failure satellite and its thrust constraint considered simultaneously. The numerical simulation results on the model of the satellite rendezvous system show that the design method proposed in this paper is effective.
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Kast, Denis, L. Kecke, and J. Ankerhold. "Charge transfer through single molecule contacts: How reliable are rate descriptions?" Beilstein Journal of Nanotechnology 2 (August 3, 2011): 416–26. http://dx.doi.org/10.3762/bjnano.2.47.
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Background: The trend for the fabrication of electrical circuits with nanoscale dimensions has led to impressive progress in the field of molecular electronics in the last decade. However, a theoretical description of molecular contacts as the building blocks of future devices is challenging, as it has to combine the properties of Fermi liquids in the leads with charge and phonon degrees of freedom on the molecule. Outside of ab initio schemes for specific set-ups, generic models reveal the characteristics of transport processes. Particularly appealing are descriptions based on transfer rates successfully used in other contexts such as mesoscopic physics and intramolecular electron transfer. However, a detailed analysis of this scheme in comparison with numerically exact solutions is still elusive. Results: We show that a formulation in terms of transfer rates provides a quantitatively accurate description even in domains of parameter space where strictly it is expected to fail, e.g., at lower temperatures. Typically, intramolecular phonons are distributed according to a voltage driven steady state that can only roughly be captured by a thermal distribution with an effective elevated temperature (heating). An extension of a master equation for the charge–phonon complex, to effectively include the impact of off-diagonal elements of the reduced density matrix, provides very accurate solutions even for stronger electron–phonon coupling. Conclusion: Rate descriptions and master equations offer a versatile model to describe and understand charge transfer processes through molecular junctions. Such methods are computationally orders of magnitude less expensive than elaborate numerical simulations that, however, provide exact solutions as benchmarks. Adjustable parameters obtained, e.g., from ab initio calculations allow for the treatment of various realizations. Even though not as rigorously formulated as, e.g., nonequilibrium Green’s function methods, they are conceptually simpler, more flexible for extensions, and from a practical point of view provide accurate results as long as strong quantum correlations do not modify the properties of the relevant subunits substantially.
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ZHAO, KUAN, and HUI M. SHAO. "A new edible bolete, Rubroboletus esculentus, from southwestern China." Phytotaxa 303, no. 3 (April 13, 2017): 243. http://dx.doi.org/10.11646/phytotaxa.303.3.4.
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A new edible species, Rubroboletus esculentus, is described from southwestern China based on both morphological characters and molecular evidence. Morphologically, this species is characterized by its vivid red and shiny pileus, fresh yellow context, orange-red to brownish yellow granulose on the yellow background of the stipe, a bluish color change, an interwoven trichodermal pileipellis embedded in a gelatinized matrix, smooth spores, a distribution in a Quercus semecarpifolia forest and a fragrant odor. Our phylogenetic analyses based on five gene markers (ITS, nrLSU, tef1-α, rpb1 and rpb2) proved it to be a new independent taxon, which was distinct from the known Rubroboletus species. Its morphological illustrations and descriptions are provided.
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ZHOU, HUIYU, TANGWEI LIU, JEFFERY Z. J. ZHENG, FAQUAN LIN, YUSHENG PANG, and JI WU. "TRACKING NON-RIGID OBJECTS IN VIDEO SEQUENCES." International Journal of Information Acquisition 03, no. 02 (June 2006): 131–37. http://dx.doi.org/10.1142/s0219878906000903.
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The recently proposed color based tracking systems are unable to properly adapt the ellipse that represents an object to be tracked. This most likely leads to inaccurate descriptions of the object in the later application. This paper presents a Lagrangian based method in order to discover a regularizing component for the covariance matrix. Technically, we intend to reduce the residuals between the estimated probability distribution and the expected one. We argue that, by doing this, the shape of the ellipse can be properly adapted in the tracking stage. Experimental results show that the proposed method has favorable performance in shape adaption and object localization.
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Xu, Biao, Xianggen Yin, Dali Wu, Shuai Pang, and Yikai Wang. "An Analytic Method for Power System Fault Diagnosis Employing Topology Description." Energies 12, no. 9 (May 10, 2019): 1770. http://dx.doi.org/10.3390/en12091770.
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When a fault occurs in a power system, fault section estimation is the primary premise for troubleshooting and power recovery, and an effective fault diagnosis system will play a big role in decision making. However, the topology information is not well employed in existing fault diagnosis methods, and it is complex and time consuming to analyze the relationship between the protective devices and the sections. In this paper, a novel analytic method which employs topology description is proposed for fault diagnosis. The topology descriptions of the sections and the protective devices are firstly established according to the network structure, and based on which the operating logic and the cooperative relationship of the protective devices can be easily analyzed by matrix operation. Considering the factors of logic error and communication error, the fault diagnosis problem is formulated as an integer programming problem and can be solved by intelligent algorithm. The case studies of different power systems show that the proposed method can quickly identify the fault section, even with the abnormal operation or error alarm of protective devices.
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SPETIK, MILAN, AKILA BERRAF-TEBBAL, DAVID GRAMAJE, ALLA EDDINE MAHAMEDI, KATERINA STUSKOVÁ, JANA BURGOVA, and ALES EICHMEIER. "Paecilomyces clematidis (Eurotiales, Thermoascaceae): a new species from Clematis root." Phytotaxa 559, no. 3 (August 25, 2022): 238–46. http://dx.doi.org/10.11646/phytotaxa.559.3.2.
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During a survey of endophytic fungi associated with ornamental plants in the Czech Republic, Paecilomyces-like strains were isolated from the root of Clematis. Analyses based on a combined internal transcribed spacer region (ITS), beta-tubulin (tub2) and calmodulin (CaM) sequence data matrix were applied to infer the phylogenetic position of these isolates. The novel species is characterized by phialides with a cylindrical basal portion tapering to a thin long neck producing pyriform conidia in chains. The new species is introduced with comprehensive descriptions, illustrations and a phylogenetic tree herein. Two primer pairs targeting the partial CaM gene, cm1F/cm1R and cm2F/cm2R, were designed in this study.
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Muir, Adrienne, and Charles Oppenheim. "Nick Moore, his information policy matrix, with a bibliometric analysis." Library Management 38, no. 8/9 (November 14, 2017): 394–403. http://dx.doi.org/10.1108/lm-02-2017-0027.
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Purpose The purpose of this paper is to examine Nick Moore’s information policy matrix and how it has been used by Moore and others. Design/methodology/approach This study involved secondary search and a bibliographic study of the impact Moore’s work has had on other authors. Findings It is clear that there have been two quite separate trains of research in information policy, one in the USA and one in Europe, and that it appears from the literature that there is limited awareness of each other’s work. Focusing on the UK and European research, the papers the authors inspected that report information policy analyses make no mention of Moore’s work. It could be argued that Moore’s matrix is too simplistic for such a complex topic as information policy, but it may also be the case that there is a lack of awareness of how the matrix can be used in policy analysis as Moore’s published papers were general descriptions of the matrix, reported the findings of his analyses or suggested policy goals. Moore did not publish theoretical or methodological papers to explain how to go about policy analysis using his matrix. Research limitations/implications This study is based on secondary research and bibliographic analysis. Furthermore, primary research could have revealed deeper insights into use and impact of Moore’s framework by analysts and policy makers. Originality/value The paper highlights potential opportunities for international collaboration on information policy research, to explore more deeply theoretical models that could be used to underpin policy analysis as well as the potential value of Moore’s matrix.
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Ramezani, Majid, Mohammad-Reza Feizi-Derakhshi, and Mohammad-Ali Balafar. "Knowledge Graph-Enabled Text-Based Automatic Personality Prediction." Computational Intelligence and Neuroscience 2022 (June 20, 2022): 1–18. http://dx.doi.org/10.1155/2022/3732351.
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How people think, feel, and behave primarily is a representation of their personality characteristics. By being conscious of the personality characteristics of individuals whom we are dealing with or deciding to deal with, one can competently ameliorate the relationship, regardless of its type. With the rise of Internet-based communication infrastructures (social networks, forums, etc.), a considerable amount of human communications takes place there. The most prominent tool in such communications is the language in written and spoken form that adroitly encodes all those essential personality characteristics of individuals. Text-based Automatic Personality Prediction (APP) is the automated forecasting of the personality of individuals based on the generated/exchanged text contents. This paper presents a novel knowledge graph-enabled approach to text-based APP that relies on the Big Five personality traits. To this end, given a text, a knowledge graph, which is a set of interlinked descriptions of concepts, was built by matching the input text’s concepts with DBpedia knowledge base entries. Then, due to achieving a more powerful representation, the graph was enriched with the DBpedia ontology, NRC Emotion Intensity Lexicon, and MRC psycholinguistic database information. Afterwards, the knowledge graph, which is now a knowledgeable alternative for the input text, was embedded to yield an embedding matrix. Finally, to perform personality predictions, the resulting embedding matrix was fed to four suggested deep learning models independently, which are based on convolutional neural network (CNN), simple recurrent neural network (RNN), long short-term memory (LSTM), and bidirectional long short-term memory (BiLSTM). The results indicated considerable improvements in prediction accuracies in all of the suggested classifiers.
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Malone, Brendan P., Alex B. McBratney, and Budiman Minasny. "Description and spatial inference of soil drainage using matrix soil colours in the Lower Hunter Valley, New South Wales, Australia." PeerJ 6 (April 16, 2018): e4659. http://dx.doi.org/10.7717/peerj.4659.
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Soil colour is often used as a general purpose indicator of internal soil drainage. In this study we developed a necessarily simple model of soil drainage which combines the tacit knowledge of the soil surveyor with observed matrix soil colour descriptions. From built up knowledge of the soils in our Lower Hunter Valley, New South Wales study area, the sequence of well-draining → imperfectly draining → poorly draining soils generally follows the colour sequence of red → brown → yellow → grey → black soil matrix colours. For each soil profile, soil drainage is estimated somewhere on a continuous index of between 5 (very well drained) and 1 (very poorly drained) based on the proximity or similarity to reference soil colours of the soil drainage colour sequence. The estimation of drainage index at each profile incorporates the whole-profile descriptions of soil colour where necessary, and is weighted such that observation of soil colour at depth and/or dominantly observed horizons are given more preference than observations near the soil surface. The soil drainage index, by definition disregards surficial soil horizons and consolidated and semi-consolidated parent materials. With the view to understanding the spatial distribution of soil drainage we digitally mapped the index across our study area. Spatial inference of the drainage index was made using Cubist regression tree model combined with residual kriging. Environmental covariates for deterministic inference were principally terrain variables derived from a digital elevation model. Pearson’s correlation coefficients indicated the variables most strongly correlated with soil drainage were topographic wetness index (−0.34), mid-slope position (−0.29), multi-resolution valley bottom flatness index (−0.29) and vertical distance to channel network (VDCN) (0.26). From the regression tree modelling, two linear models of soil drainage were derived. The partitioning of models was based upon threshold criteria of VDCN. Validation of the regression kriging model using a withheld dataset resulted in a root mean square error of 0.90 soil drainage index units. Concordance between observations and predictions was 0.49. Given the scale of mapping, and inherent subjectivity of soil colour description, these results are acceptable. Furthermore, the spatial distribution of soil drainage predicted in our study area is attuned with our mental model developed over successive field surveys. Our approach, while exclusively calibrated for the conditions observed in our study area, can be generalised once the unique soil colour and soil drainage relationship is expertly defined for an area or region in question. With such rules established, the quantitative components of the method would remain unchanged.
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Chen, Shu Lin, Fang Fang Yu, Guo Lei Zheng, Bao Rui Du, and Hong Zhen Chu. "Machining Feature Sequencing for Aircraft Structural Parts." Advanced Materials Research 591-593 (November 2012): 361–64. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.361.
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To improve quality and efficiency of NC machining sequencing, an approach to order the machining features of aircraft structural parts is introduced in accordance with the principle of hierarchical planning, knowledge and geometry-based reasoning method. The main contents consist of: (1) Machining cell and its geometric descriptions are established, and the method for decomposing generalized pocket (GP) into machining cells is proposed. (2) Based on the GP relationship tree, data model and algorithm for generating machining chain are presented. (3) Machining process segmenting, feature grouping and sequencing rules are formulated by communicating with related experts. (4) Priority graph and relationship matrix of features are applied to describe the machining precedence. The developed approach has been applied in Intelligent NC Programming System of Aircraft Structural Parts and is validated through a case study.
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Velichkin, Vladimir, Vladimir Zavyalov, Elena Solodovnikova, and Elena Filippova. "Mathematical descriptions of heat-mass-exchange processes in construction industry at control automation." E3S Web of Conferences 97 (2019): 06021. http://dx.doi.org/10.1051/e3sconf/20199706021.
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The paper covers matters arising in building mathematical model of processes at thermal treatment of construction materials. On the basis of analysis of heat energy and moisture flows in intermittent steam chamber and continuous tunnel drying chamber, analytic and structure models of heat-mass-exchange processes in processing vessels are drawn. The structural model of heat-mass-exchange processes allowed to evaluate the relationship of heat energy and moisture flows at heat treatment processes for gypsum and reinforced-concrete articles. The resulting system of interrelated differential equations is based on a structural model. Analytical studies showed that the considering heat treatment units are characterized by non-stationary, non-linear, stochastic and distributed technological parameters. An experimental study of technological devices has shown that in a limited time range, the processes of heat-mass-exchange can be characterized by a system of linear differential equations with constant coefficients with sufficient accuracy for practice. Acceptable allowances and simplifying assumptions at analytical description of heat-mass-exchange processes in processing vessels are considered. As a result of performed research, various mathematical forms (differential equation system, matrix and operator forms) of mathematical models of processing vessels are obtained. The built mathematical models may be applied for constructing the processing vessels with preset dynamic properties, as well for control-system designing by those vessels.
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Rubbenstroth, Dennis, Martin Ryll, Helmut Hotzel, Henrik Christensen, Johannes Karl-Mark Knobloch, Silke Rautenschlein, and Magne Bisgaard. "Description of Riemerella columbipharyngis sp. nov., isolated from the pharynx of healthy domestic pigeons (Columba livia f. domestica), and emended descriptions of the genus Riemerella , Riemerella anatipestifer and Riemerella columbina." International Journal of Systematic and Evolutionary Microbiology 63, Pt_1 (January 1, 2013): 280–87. http://dx.doi.org/10.1099/ijs.0.036798-0.
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A group of 11 bacterial strains was isolated during microbiological investigations of pharyngeal swabs collected from domestic pigeons (Columba livia f. domestica). Phenotypic properties of the isolates closely resembled those of members of the genus Riemerella within the family Flavobacteriaceae . The genus presently contains two species, Riemerella anatipestifer and Riemerella columbina . The pigeon isolates differed from R. columbina by their lack of pigment production and negative CAMP co-haemolysis reaction. They grew more slowly at 37 °C under microaerobic conditions and showed reduced viability during storage under aerobic conditions at different temperatures, compared with both Riemerella species. Comparisons of protein profiles with matrix-assisted laser desorption/ionization–time of flight (MALDI-TOF) MS analysis allowed differentiation between the new pigeon isolates and both R. anatipestifer and R. columbina . Phylogenetic analysis based on 16S rRNA gene and rpoB gene (encoding RNA polymerase beta subunit) sequences supported the affiliation of the 11 strains to a novel species within the genus Riemerella , for which we propose the name Riemerella columbipharyngis sp. nov. The type strain is 8151T ( = DSM 24015T = LMG 26094T). Emended descriptions of the genus Riemerella and of its species Riemerella anatipestifer and Riemerella columbina are also presented.
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YANG, YI, SHENG-NAN ZHANG, XIAN-DONG YU, and JIAN-KUI LIU. "Pseudokeissleriella bambusicola gen. et sp. nov. (Lentitheciaceae, Pleosporales) from bamboos in Sichuan province, China." Phytotaxa 560, no. 3 (September 2, 2022): 263–73. http://dx.doi.org/10.11646/phytotaxa.560.3.1.
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During an investigation of ascomycetous fungi on bamboos in Sichuan province, China, a monotypic genus, Pseudokeissleriella, collected from dead culms of bamboos is introduced to accommodate P. bambusicola. Pseudokeissleriella bambusicola is characterized by having subglobose to globose, glabrous ascomata, and hyaline, septate, fusiform ascospores with subobtuse ends and a swollen upper cell, surrounded by a mucilaginous sheath with center depression. The phylogenetic analyses based on multi-gene matrix of SSU, ITS, LSU, tef-1α sequences showed that P. bambusicola presented a distinct lineage sister to Katumotoa and Neoophiosphaerella in Lentitheciaceae. The establishment of new taxa were justified by morphological and phylogenetic evidences. Morpho-phylogenetic differences between Pseudokeissleriella and some related genera Katumotoa, Keissleriella, and Neoophiosphaerella are discussed. Descriptions, illustrations, and notes for the new taxa are provided.
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Feng, Ji Ling, Shi Wen Wang, and Jian Guo Lin. "Multi-Resolution Material Hardening Law for CPFE Micro-Forming Analysis." Key Engineering Materials 716 (October 2016): 232–39. http://dx.doi.org/10.4028/www.scientific.net/kem.716.232.
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A new multi-resolution slip system-based material hardening law has been developed for micro-forming simulation using Crystal Plasticity Finite Element (CPFE) Approach. Material hardenings are formulated based on global and local hardening of dislocations for each slip system and defined with distinct physical meaning. Plasticity is assumed to arise solely from crystalline slip and the overall mechanical response with any crystallographic system, such as FCC, BCC, etc, can be addressed by a local hardening parameter, c, from 0 (pure anisotropic) to 1 (fully isotropic). No interaction matrix is necessary, since the latent hardening can be realized by the hardening factor , c , and the new dislocation density based hardening law can be implemented into existing FE software efficiently. The proposed equations are an extension of the existing hardening law from macro mechanics descriptions down to micro mechanics level, therefore unified constitutive equations had been established at multiscale resolution. Some features of the proposed hardening law will be demonstrated with a single cubic crystal under tension load.
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McGarvey, Richard, and John E. Feenstra. "Estimating length-transition probabilities as polynomial functions of premoult length." Marine and Freshwater Research 52, no. 8 (2001): 1517. http://dx.doi.org/10.1071/mf01172.
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In length-based lobster stock-assessment models where the population is subdivided into discrete length classes, growth is represented as a matrix of length-transition probabilities. At specific times during the model year, the length-transition probabilities specify the proportions growing into larger length classes. These probabilities are calculated by integration of gamma or normal distributions over the length intervals of each larger length class. The mean growth from any given length category is commonly modelled by a von Bertalanffy or other continuous growth curve. The coefficients of variation, describing variance among individuals, are modelled by functions constant or linear with length. These approaches have yielded good descriptions of growth for males and juveniles, but the von Bertalanffy curve does not capture the rapid decrease in mean growth rate after maturity for females. We generalized this length-transition model by writing the parameters of the growth distributions as polynomial functions of carapace length. This generalization procedure increases the number of parameters depending on the degree of polynomial employed. In fits to South Australian rock lobster (Jasus edwardsii) tagrecovery data, each increase in polynomial degree yielded a significantly better fit for females and successfully represented the decrease in growth at maturity. For males, the von Bertalanffy description was little improved by higher polynomials.
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Polyakov, Vladimir N., Elena A. Makarova, and Valery D. Solovyev. "Phylogenetic trees: Grammar versus vocabulary." Russian Journal of Linguistics 26, no. 1 (March 30, 2022): 31–50. http://dx.doi.org/10.22363/2687-0088-26460.
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Traditionally, genealogical relationships between languages are established on the basis of phonetic and lexical data. The question whether genealogical relationships among languages can be defined based on grammatical data remains unanswered. The objective of this article is to compare two phylogenetic trees: one built using the Automated Similarity Judgment Program (ASJP) project, and one using the World Atlas of Language Structures (WALS). We include data from WALS representing 27 languages from 5 language families of all continents that are deemed to be sufficiently well described. A Hamming distance matrix was calculated for all languages under study, and, based on the matrix, a phylogenetic tree was built. The trees built according to WALS and ASJP data are compared with each other and with a tree built by the classical comparative historical method. Both the ASJP-based tree and the WALS-based tree have their advantages and disadvantages. The ASJP-based tree is a good reflection of the evolutionary divergence of languages. Similarities of languages as calculated based on the typological database of WALS can provide information on the history of languages both in terms of genealogical descent and contact with other languages. The ASJP-based tree reflects genealogical relationship well at a relatively small time depth, while the WALS-based tree reflects genealogical relationship well at large time intervals. We suggest a new variant of a phylogenetic tree that includes information on both the divergence (ASJP project) and the convergence (WALS project) of languages, combining the benefits of both of these trees, although the problem of borrowings remains. The present research reveals prospects for future studies of genealogical relations among languages based on large-scale descriptions of their grammatical structures.
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Schmitt, Oliver, Peter Eipert, Sebastian Schwanke, Felix Lessmann, Jennifer Meinhardt, Julia Beier, Kanar Kadir, et al. "Connectome verification: inter-rater and connection reliability of tract-tracing-based intrinsic hypothalamic connectivity." Briefings in Bioinformatics 20, no. 5 (June 3, 2019): 1944–55. http://dx.doi.org/10.1093/bib/bby048.
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Abstract Motivation Structural connectomics supports understanding aspects of neuronal dynamics and brain functions. Conducting metastudies of tract-tracing publications is one option to generate connectome databases by collating neuronal connectivity data. Meanwhile, it is a common practice that the neuronal connections and their attributes of such retrospective data collations are extracted from tract-tracing publications manually by experts. As the description of tract-tracing results is often not clear-cut and the documentation of interregional connections is not standardized, the extraction of connectivity data from tract-tracing publications could be complex. This might entail that different experts interpret such non-standardized descriptions of neuronal connections from the same publication in variable ways. Hitherto, no investigation is available that determines the variability of extracted connectivity information from original tract-tracing publications. A relatively large variability of connectivity information could produce significant misconstructions of adjacency matrices with faults in network and graph analyzes. The objective of this study is to investigate the inter-rater and inter-observation variability of tract-tracing-based documentations of neuronal connections. To demonstrate the variability of neuronal connections, data of 16 publications which describe neuronal connections of subregions of the hypothalamus have been assessed by way of example. Results A workflow is proposed that allows detecting variability of connectivity at different steps of data processing in connectome metastudies. Variability between three blinded experts was found by comparing the connection information in a sample of 16 publications that describe tract-tracing-based neuronal connections in the hypothalamus. Furthermore, observation scores, matrix visualizations of discrepant connections and weight variations in adjacency matrices are analyzed. Availability The resulting data and software are available at http://neuroviisas.med.uni-rostock.de/neuroviisas.shtml
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LUO, BIN, EDWIN HANCOCK, and RICHARD WILSON. "EIGENSPACES FOR GRAPHS." International Journal of Image and Graphics 02, no. 02 (April 2002): 247–68. http://dx.doi.org/10.1142/s0219467802000603.
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In this paper, we investigate the feasibility of using graph-based descriptions to learn the view structure of 3D objects. The graphs used in our study are constructed from the Delaunay triangulations of corner features. The investigation is divided into two parts. We commence by considering how relational structures can be encoded in a way which can be used to generate parametric eigenspaces. Here we investigate four different relational representations derived from the graphs. The first three of these are vector encodings of the adjacency graph, the weighted adjacency graph, and the point proximity matrix; the fourth representation is the edge weight histogram. We study the eigenspaces which result from these different representations. In addition, we investigate how multidimensional scaling may be used to generate eigenspaces from a set of pairwise distances between graphs.
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Botros, K. K., P. J. Campbell, and D. B. Mah. "Dynamic Simulation of Compressor Station Operation Including Centrifugal Compressor and Gas Turbine." Journal of Engineering for Gas Turbines and Power 113, no. 2 (April 1, 1991): 300–311. http://dx.doi.org/10.1115/1.2906563.
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Dynamic simulation of the operation of a compressor station requires mathematical modeling of the dynamic behavior of the compressor unit and various piping elements. Such models consist of large systems of nonlinear partial differential equations describing the pipe flow together with nonlinear algebraic equations describing the quasi-steady flow through various valves, constrictions, and compressors. In addition, the models also include mathematical descriptions of the control system, which consists of mixed algebraic and ordinary differential (mad) equations with some inequalities representing controllers’ limits. In this paper a numerical technique for the solution of the gas dynamics equations is described, based on the transfer matrix formulation relating the state vector time difference at one side of an element to that on the other side. This approach facilitates incorporation of all element transfer matrices into an overall transfer matrix according to the system geometric connectivity. The paper also presents simulation results and comparison with actual field measurements of three case histories: (1) simulation of a compressor surge protection control process; (2) unit startup; and (3) slow transient of a compressor station responding to changes in the discharge pressure set point. Good agreement between simulation results and field measurements is demonstrated.
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GAO, YING, JUTAMART MONKAI, ELENI GENTEKAKI, GUANG-CONG REN, DHANUSHKA N. WANASINGHE, JIAN-CHU XU, and HENG GUI. "Dothidea kunmingensis, a novel asexual species of Dothideaceae on Jasminum nudiflorum (winter jasmine) from Southwestern China." Phytotaxa 529, no. 1 (December 30, 2021): 43–56. http://dx.doi.org/10.11646/phytotaxa.529.1.3.
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During a survey of saprobic microfungi in Southwest China, a coelomycetous fungus was found on dead twigs of Jasminum nudiflorum in Kunming, Yunnan Province. Based on a detailed morphological characterization coupled with multi-locus phylogenetic analyses, the fungus was identified as a new species in the genus Dothidea. Phylogenetic analyses using a combined matrix consisting of internal transcribed spacer (ITS), large subunit rRNA (LSU), small subunit rRNA (SSU), beta tubulin (tub2) and translation elongation factor-1 alpha (tef1-α) confirmed its placement in Dothideaceae and revealed a sister relationship to Dothidea eucalypti. The new species is characterized by pycnidial conidiomata, ampulliform or doliiform conidiogenous cells as well as aseptate, subglobose to ovoid, hyaline to pale-brown conidia. Comprehensive descriptions and illustrations are provided. Morphological characteristics of asexual morph taxa in Dothideaceae are also summarized and discussed.
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Qin, Guojun, and Jingfang Wang. "Random Sampling and Signal Bregman Reconstruction Based on Compressed Sensing." Indonesian Journal of Electrical Engineering and Computer Science 4, no. 2 (November 1, 2016): 365. http://dx.doi.org/10.11591/ijeecs.v4.i2.pp365-372.
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Compressed sensing (CS) sampling is a sampling method which is based on the signal sparse. Much information can be extracted from as little as possible of the data by applying CS and this method is the idea of great theoretical and applied prospects. In the framework of compressed sensing theory, the sampling rate is no longer decided in the bandwidth of the signal, but it depends on the structure and content of the information in the signal. In this paper, the signal is the sparse in the Fourier transform and random sparse sampling is advanced by programing random observation matrix for peak random base. The signal is successfully restored by the use of Bregman algorithm. The signal is described in the transform space, and a theoretical framework is established with a new signal descriptions and processing. By making the case to ensure that the information loss, signal is sampled at much lower than the Nyquist sampling theorem requiring rate,but also the signal is completely restored in high probability. The random sampling has following advantages: alias-free sampling frequency need not obey the Nyquist limit and higher frequency resolution.
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HARA, MARCOS RYOTARO, RICARDO PINTO-DA-ROCHA, and ADRIANO BRILHANTE KURY. "Revision of Nanophareus, a mysterious harvestman genus from Chile, with descriptions of three new species (Opiliones: Laniatores: Gonyleptidae)." Zootaxa 3579, no. 1 (December 11, 2012): 37. http://dx.doi.org/10.11646/zootaxa.3579.1.2.
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The Chilean genus Nanophareus Roewer, 1929 is revised and three new species are described: N. araucanus sp. nov. (typelocality: Parque Nacional La Campana, Valparaíso, Chile); N. bipartitus sp. nov. (type locality: Parque Nacional La Cam-pana, Valparaíso, Chile); N. bosqenublado sp. nov. (type locality: Parque Nacional Fray Jorge, Coquimbo, Chile). Thetype species, N. palpalis Roewer, 1929, is redescribed and a lectotype is designated. A cladistic analysis was performedusing these three new species plus N. palpalis and 14 more laniatorid species, and a data matrix of 72 characters: Sevenfrom the ocularium, 22 from the dorsal scutum, one from the venter, one from the chelicera, eight from the pedipalp, 24from male legs, and nine from male genitalia. Two equally most parsimonious trees were found (L = 210; C.I. = 0.41; R.I.= 0.51). Nanophareus was recovered as nested within a paraphyletic subfamily Pachylinae. The genus Nanophareus wasfound to be monophyletic based on the following exclusive synapomorphies: An external row of enlarged tubercles in-serted among small ones on lateral margin of the dorsal scutum (innapplicable in N. bosqenublado); the ventro-basal mar-gin of pedipalpal tibia curved 90 degrees in lateral view; and retrolateral seta of the pedipalpal tibia with a socket apically bifid (socket and seta longer than pedipalpal tibia length).
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Lin, Yin-Ku, Shih-Chun Yang, Ching-Yun Hsu, Jui-Tai Sung, and Jia-You Fang. "The Antibiofilm Nanosystems for Improved Infection Inhibition of Microbes in Skin." Molecules 26, no. 21 (October 22, 2021): 6392. http://dx.doi.org/10.3390/molecules26216392.
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Biofilm formation is an important virulence factor for the opportunistic microorganisms that elicit skin infections. The recalcitrant feature of biofilms and their antibiotic tolerance impose a great challenge on the use of conventional therapies. Most antibacterial agents have difficulty penetrating the matrix produced by a biofilm. One novel approach to address these concerns is to prevent or inhibit the formation of biofilms using nanoparticles. The advantages of using nanosystems for antibiofilm applications include high drug loading efficiency, sustained or prolonged drug release, increased drug stability, improved bioavailability, close contact with bacteria, and enhanced accumulation or targeting to biomasses. Topically applied nanoparticles can act as a strategy for enhancing antibiotic delivery into the skin. Various types of nanoparticles, including metal oxide nanoparticles, polymeric nanoparticles, liposomes, and lipid-based nanoparticles, have been employed for topical delivery to treat biofilm infections on the skin. Moreover, nanoparticles can be designed to combine with external stimuli to produce magnetic, photothermal, or photodynamic effects to ablate the biofilm matrix. This study focuses on advanced antibiofilm approaches based on nanomedicine for treating skin infections. We provide in-depth descriptions on how the nanoparticles could effectively eliminate biofilms and any pathogens inside them. We then describe cases of using nanoparticles for antibiofilm treatment of the skin. Most of the studies included in this review were supported by in vivo animal infection models. This article offers an overview of the benefits of nanosystems for treating biofilms grown on the skin.
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LI, WEN-LI, ZUO-PENG LIU, TIAN ZHANG, ASHA J. DISSANAYAKE, ZONG-LONG LUO, HONG-YAN SU, and JIAN-KUI LIU. "Additions to Distoseptispora (Distoseptisporaceae) associated with submerged decaying wood in China." Phytotaxa 520, no. 1 (September 13, 2021): 75–86. http://dx.doi.org/10.11646/phytotaxa.520.1.5.
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In this study, five aquatic hyphomycetous taxa were collected and isolated from submerged wood in Lancang River located in the northwestern Yunnan Province of China. Phylogenetic analyses based on combined LSU, ITS, tef1α and rpb2 sequence matrix indicated that those five taxa belonging to Distoseptispora (Distoseptisporaceae), and they can be recognized as four species which two are introduced as new species (Distoseptispora euseptatensis and D. yunnanensis) and two are identified as D. aquatica and D. tectonae. Two isolates of the new species Distoseptispora euseptatensis formed a distinct clade among Distoseptispora species (basal to D. suoluoensis and D. bambusae) with good support (ML 100%, MP 100%, BI 1.00 PP). Distoseptispora yunnanensis clustered together with D. euseptatensis, but they are difference in the size of conidiophore and conidia. Corresponding illustrations, descriptions and phylogenetic evidences are provided to justify the placement of our newly collected Distoseptispora taxa.
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Ren, Guang-Cong, Dhanushka N. Wanasinghe, Rajesh Jeewon, Jutamart Monkai, Peter E. Mortimer, Kevin D. Hyde, Jian-Chu Xu, and Heng Gui. "Taxonomy and phylogeny of the novel rhytidhysteron-like collections in the Greater Mekong Subregion." MycoKeys 86 (January 12, 2022): 65–85. http://dx.doi.org/10.3897/mycokeys.86.70668.
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During our survey into the diversity of woody litter fungi across the Greater Mekong Subregion, three rhytidhysteron-like taxa were collected from dead woody twigs in China and Thailand. These were further investigated based on morphological observations and multi-gene phylogenetic analyses of a combined DNA data matrix containing SSU, LSU, ITS, and tef1-α sequence data. A new species of Rhytidhysteron, R. xiaokongense sp. nov. is introduced with its asexual morph, and it is characterized by semi-immersed, subglobose to ampulliform conidiomata, dark brown, oblong to ellipsoidal, 1-septate, conidia, which are granular in appearance when mature. In addition to the new species, two new records from Thailand are reported viz. Rhytidhysteron tectonae on woody litter of Betula sp. (Betulaceae) and Fabaceae sp. and Rhytidhysteron neorufulum on woody litter of Tectona grandis (Lamiaceae). Morphological descriptions, illustrations, taxonomic notes and phylogenetic analyses are provided for all entries.
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Burman, Erik, Peter Hansbo, Mats G. Larson, and André Massing. "Cut finite element methods for partial differential equations on embedded manifolds of arbitrary codimensions." ESAIM: Mathematical Modelling and Numerical Analysis 52, no. 6 (November 2018): 2247–82. http://dx.doi.org/10.1051/m2an/2018038.
Full textAbstract:
We develop a theoretical framework for the analysis of stabilized cut finite element methods for the Laplace-Beltrami operator on a manifold embedded in ℝd of arbitrary codimension. The method is based on using continuous piecewise linears on a background mesh in the embedding space for approximation together with a stabilizing form that ensures that the resulting problem is stable. The discrete manifold is represented using a triangulation which does not match the background mesh and does not need to be shape-regular, which includes level set descriptions of codimension one manifolds and the non-matching embedding of independently triangulated manifolds as special cases. We identify abstract key assumptions on the stabilizing form which allow us to prove a bound on the condition number of the stiffness matrix and optimal order a priori estimates. The key assumptions are verified for three different realizations of the stabilizing form including a novel stabilization approach based on penalizing the surface normal gradient on the background mesh. Finally, we present numerical results illustrating our results for a curve and a surface embedded in ℝ3.
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Rosinová, Danica, and Mária Hypiusová. "LMI Pole Regions for a Robust Discrete-Time Pole Placement Controller Design." Algorithms 12, no. 8 (August 13, 2019): 167. http://dx.doi.org/10.3390/a12080167.
Full textAbstract:
Herein, robust pole placement controller design for linear uncertain discrete time dynamic systems is addressed. The adopted approach uses the so called “D regions” where the closed loop system poles are determined to lie. The discrete time pole regions corresponding to the prescribed damping of the resulting closed loop system are studied. The key issue is to determine the appropriate convex approximation to the originally non-convex discrete-time system pole region, so that numerically efficient robust controller design algorithms based on Linear Matrix Inequalities (LMI) can be used. Several alternatives for relatively simple inner approximations and their corresponding LMI descriptions are presented. The developed LMI region for the prescribed damping can be arbitrarily combined with other LMI pole limitations (e.g., stability degree). Simple algorithms to calculate the matrices for LMI representation of the proposed convex pole regions are provided in a concise way. The results and their use in a robust controller design are illustrated on a case study of a laboratory magnetic levitation system.