Quantification of Scenario Distance within Generic WINNER Channel Model

International Journal of Antennas and Propagation ◽

10.1155/2013/176704 ◽

2013 ◽

Vol 2013 ◽

pp. 1-17 ◽

Cited By ~ 5

Author(s):

Milan Narandžić ◽

Christian Schneider ◽

Wim Kotterman ◽

Reiner S. Thomä

Keyword(s):

Channel Model ◽

Probability Distributions ◽

Correlation Coefficients ◽

Mimo Channel ◽

Normal Probability ◽

Leibler Divergence ◽

Suitable Space ◽

Indoor Scenarios ◽

Stochastic Properties

Starting from the premise that stochastic properties of a radio environment can be abstracted by defining scenarios, a generic MIMO channel model is built by the WINNER project. The parameter space of the WINNER model is, among others, described by normal probability distributions and correlation coefficients that provide a suitable space for scenario comparison. The possibility to quantify the distance between reference scenarios and measurements enables objective comparison and classification of measurements into scenario classes. In this paper we approximate the WINNER scenarios with multivariate normal distributions and then use the mean Kullback-Leibler divergence to quantify their divergence. The results show that the WINNER scenario groups (A, B, C, and D) or propagation classes (LoS, OLoS, and NLoS) do not necessarily ensure minimum separation within the groups/classes. Instead, the following grouping minimizes intragroup distances: (i) indoor-to-outdoor and outdoor-to-indoor scenarios (A2, B4, and C4), (ii) macrocell configurations for suburban, urban, and rural scenarios (C1, C2, and D1), and (iii) indoor/hotspot/microcellular scenarios (A1, B3, and B1). The computation of the divergence between Ilmenau and Dresden measurements and WINNER scenarios confirms that the parameters of the C2 scenario are a proper reference for a large variety of urban macrocell environments.

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MU-MIMO Channel Model with User Parameters and Correlation between Channel Matrix Elements in Small Area of Multipath Environment

IEICE Transactions on Communications ◽

10.1587/transcom.2019ebp3171 ◽

2020 ◽

Vol E103.B (12) ◽

pp. 1421-1431

Author(s):

Shigeru KOZONO ◽

Yuya TASHIRO ◽

Yuuki KANEMIYO ◽

Hiroaki NAKABAYASHI

Keyword(s):

Small Area ◽

Channel Model ◽

Mimo Channel ◽

Matrix Elements ◽

Channel Matrix ◽

Multipath Environment

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Potential Use of Aquatic Macrophytes to Enhance the Treatment of Septic Tank Liquids

Water Science & Technology ◽

10.2166/wst.1999.0166 ◽

1999 ◽

Vol 40 (3) ◽

pp. 225-232 ◽

Cited By ~ 2

Author(s):

S. Perdomo ◽

C. Bangueses ◽

J. Fuentes

Keyword(s):

Aquatic Macrophytes ◽

Typha Latifolia ◽

Correlation Coefficients ◽

Statistical Characteristics ◽

Septic Tank ◽

Conventional System ◽

Normal Probability ◽

Complete Treatment ◽

Floating Macrophyte ◽

Potential Use

In several urban and suburban areas, the problem of the disposal and treatment of septic tank liquids has not been solved yet. This paper deals with the primary operational evaluation of a conventional system of ponds used at Tarariras, in the Department of Colonia, Uruguay, as well as the potential use of aquatic macrophytes to enhance such treatment. The conventional system was sampled over a period of approximately one month at the end of the summer in order to determine the main parameters. Groups of up to 20 samples were studied to determine the normal distributions. Correlation coefficients were obtained for the normal probability plot between 0.84 and 0.99. The most relevant statistical characteristics were calculated for each parameter. The removal efficiency was 80.0% of BOD5, 58.5% of COD, 75.8% of NH4+-N, 9.5% of PO4−3-P and 38.5% of TSS. At the same time, batch and semi-continuous trials were carried out at bench scale with Eichhornia crassipes (floating macrophyte) and Typha latifolia (emergent macrophyte). The best efficiencies were obtained for the latter, with values of 96.6% of BOD5, 93.0% of COD, 99.6% of NH4+-N, 95.2% of PO4−3-P and 95.5% of TSS. It was concluded that constructed wetlands could be the answer to a more complete treatment process.

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Chemometric Analysis for the Classification of some Groups of Drugs with Divergent Pharmacological Activity on the Basis of some Chromatographic and Molecular Modeling Parameters

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180129102149 ◽

2018 ◽

Vol 21 (2) ◽

pp. 125-137

Author(s):

Jolanta Stasiak ◽

Marcin Koba ◽

Marcin Gackowski ◽

Tomasz Baczek

Keyword(s):

Correlation Analysis ◽

Pharmacological Activity ◽

Correlation Coefficients ◽

Principal Component ◽

Cardiovascular Drugs ◽

New Drugs ◽

Analgesic Drugs ◽

Starting Point ◽

Chromatographic Parameters

Aim and Objective: In this study, chemometric methods as correlation analysis, cluster analysis (CA), principal component analysis (PCA), and factor analysis (FA) have been used to reduce the number of chromatographic parameters (logk/logkw) and various (e.g., 0D, 1D, 2D, 3D) structural descriptors for three different groups of drugs, such as 12 analgesic drugs, 11 cardiovascular drugs and 36 “other” compounds and especially to choose the most important data of them. Material and Methods: All chemometric analyses have been carried out, graphically presented and also discussed for each group of drugs. At first, compounds’ structural and chromatographic parameters were correlated. The best results of correlation analysis were as follows: correlation coefficients like R = 0.93, R = 0.88, R = 0.91 for cardiac medications, analgesic drugs, and 36 “other” compounds, respectively. Next, part of molecular and HPLC experimental data from each group of drugs were submitted to FA/PCA and CA techniques. Results: Almost all results obtained by FA or PCA, and total data variance, from all analyzed parameters (experimental and calculated) were explained by first two/three factors: 84.28%, 76.38 %, 69.71% for cardiovascular drugs, for analgesic drugs and for 36 “other” compounds, respectively. Compounds clustering by CA method had similar characteristic as those obtained by FA/PCA. In our paper, statistical classification of mentioned drugs performed has been widely characterized and discussed in case of their molecular structure and pharmacological activity. Conclusion: Proposed QSAR strategy of reduced number of parameters could be useful starting point for further statistical analysis as well as support for designing new drugs and predicting their possible activity.

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Semi-automated classification of colonial Microcystis by FlowCAM imaging flow cytometry in mesocosm experiment reveals high heterogeneity during seasonal bloom

Scientific Reports ◽

10.1038/s41598-021-88661-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yersultan Mirasbekov ◽

Adina Zhumakhanova ◽

Almira Zhantuyakova ◽

Kuanysh Sarkytbayev ◽

Dmitry V. Malashenkov ◽

...

Keyword(s):

Machine Learning ◽

Flow Cytometry ◽

Spatial Resolution ◽

Mesocosm Experiment ◽

Imaging Flow Cytometry ◽

Leibler Divergence ◽

Temporal And Spatial ◽

High Level ◽

Training Sets

AbstractA machine learning approach was employed to detect and quantify Microcystis colonial morphospecies using FlowCAM-based imaging flow cytometry. The system was trained and tested using samples from a long-term mesocosm experiment (LMWE, Central Jutland, Denmark). The statistical validation of the classification approaches was performed using Hellinger distances, Bray–Curtis dissimilarity, and Kullback–Leibler divergence. The semi-automatic classification based on well-balanced training sets from Microcystis seasonal bloom provided a high level of intergeneric accuracy (96–100%) but relatively low intrageneric accuracy (67–78%). Our results provide a proof-of-concept of how machine learning approaches can be applied to analyze the colonial microalgae. This approach allowed to evaluate Microcystis seasonal bloom in individual mesocosms with high level of temporal and spatial resolution. The observation that some Microcystis morphotypes completely disappeared and re-appeared along the mesocosm experiment timeline supports the hypothesis of the main transition pathways of colonial Microcystis morphoforms. We demonstrated that significant changes in the training sets with colonial images required for accurate classification of Microcystis spp. from time points differed by only two weeks due to Microcystis high phenotypic heterogeneity during the bloom. We conclude that automatic methods not only allow a performance level of human taxonomist, and thus be a valuable time-saving tool in the routine-like identification of colonial phytoplankton taxa, but also can be applied to increase temporal and spatial resolution of the study.

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Spatial characterization of propagation channels for terahertz band

SN Applied Sciences ◽

10.1007/s42452-021-04262-8 ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Bilal Aghoutane ◽

Mohammed El Ghzaoui ◽

Hanan El Faylali

Keyword(s):

Communication Systems ◽

Indoor Environment ◽

Channel Model ◽

Path Loss ◽

Propagation Loss ◽

Terahertz Band ◽

Indoor Scenarios ◽

Transmission Windows ◽

Sv Channel

AbstractThe aim of this work consists in characterizing the Terahertz (THz) propagation channel in an indoor environment, in order to propose a channel model for THz bands. We first described a propagation loss model by taking into account the attenuation of the channel as a function of distance and frequency. The impulse response of the channel is then described by a set of rays, characterized by their amplitude, their delay and their phase. Apart from the frequency selective nature, path loss in THz band is also an others issue associated with THz communication systems. This work based on the conventional Saleh-Valenzuela (SV) model which is intended for indoor scenarios. In this paper, we have introduced random variables as Line of sight (LOS) component, and then merging it with the SV channel model to adopt it to the THz context. From simulation, we noted an important effect when the distance between the transmitter and the receiver change. This effect produces variations in frequency loss. The simulations carried out from this model show that to enhance the performance of THz system it is recommended to transmit information over transmission windows instead over the whole band.

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