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Laser-induced fluorescence (LIF) spectra of biological tissues spectra have continuous nature and can be statistically analyzed using principal components (PC) method. The disadvantage of this method is that PCs are abstract functions, alternating, giving both positive and negative contribution to the spectrum that it is impossible for the real fluorophores. In present paper the PC analysis was adapted to spectroscopy tasks by composing positive linear combinations of PCs corresponding to the peaks of the smallest width with the largest ratio of the spectral maximum to its integral across the measured wavelength range. This method was applied for the analysis of previously obtained LIF spectra of the intact teeth and teeth with caries, and spectra of aortal graft before and after decellularization. The representation of the principal components in the form of peaks with the smallest possible width allowed us to identify the number fluorophores contributing the spectra, their approximate spectra, to perform a statistical analysis of the data and its interpretation. [ABSTRACT FROM AUTHOR]

Several studies can be found where the mechanical strength of fiber composites is evaluated, but not much can be found regarding the influence of voids, as a second phase, in the same mechanical behavior of materials. In the present work, the influence of bubble presence into translucid polymeric bars is investigated. For this purpose, cubic probes with an anisotropic distribution of bubbles were casted, and other were casted controlling the manufacture process to avoid the bubble formation. Each probe was placed in a He-Ne laser-photoelastic arrangement and subjected to compression by an static load. The transmitted 630 nm, He-Ne laser beam was captured by a single mode fiber optic sensor and then transmitted to a spectrometer and PC. Analysis of the spectrometer signals showed that the maximum stresses are concentrated on the bubbles reducing the surface stresses and inducing damping on the probe. The amount of damping depends on the size of the bubbles formed within the probe and their arrangement, thus it can be anticipated that stresses can be directed for specific arrangements in size of bubbles. A white light was also employed in substitution of the laser to investigated the effect of wave length on the results previously obtained. The effect of damping was also experienced but although more information could be obtained caused of the non-coherent nature of the light, it was no possible to obtain full information of the structure of the probes. [ABSTRACT FROM AUTHOR]

The regular principal components (PC) analysis of stochastic processes is extended to the constrained principal components (CPC) problem. As in the PC analysis, the CPC analysis involves extracting representative components which contain the most information about the original processes. In contrast to the PC problem, the CPC solution has to be extracted from a given constraint subspace. Therefore, the CPC solution may be adopted to best recover the original signal and simultaneously avoid the undesirable noisy or redundant components. This is very appealing in many practical applications. A technique is proposed for finding optimal CPC solutions with an orthogonal learning network (OLN). The underlying numerical analysis for the theoretical proof of the convergency of OLN is discussed. As a byproduct, the same numerical analysis also provides a useful estimate of optimal learning rates, leading to very fast convergence speed. Simulation and application examples are provided [ABSTRACT FROM PUBLISHER]

Current information sharing networks today offer a valuable medium to express emotions, feelings, ideas and opinions, as well as interactions between individuals from different walks of life. Nowadays, there are currently 2.62 billion social networks for active users. Social networks are used to exchange ideas and knowledge allowing individuals, groups and organisations to connect. This provides a large and rich pool of knowledge that can play a critical role for corporations, governments, political campaigns as well as administrative management and welfare in decision making. Most posts on the Internet are in the form of text, which can be processed to mine people's sentiments and emotional feelings. People do not realise that text on digital media platforms can be a threat to society's peace when judged with excessive emotions. Excessive emotions from citizens can bring unwanted risks including riots and civil war. Any threat to society's peace needs to be addressed as it can weaken national security. For this purpose, this paper explores a hybrid technique to classify people's emotions in text from online news that can affect national security using the lexicon-based approach and Kansei to determine sentiment polarity and emotions in text. The findings from this study can be utilised as a foundation for opinion mining in the national security domain. [ABSTRACT FROM AUTHOR]

The dependence of the population and activity of reservoir microflora upon the chemical composition and viscosity of crude oils has been investigated, since it allows the problem of improvement in the technologies and enhancement of oil recovery as applied to production of difficult types of oils with anomalous properties (viscous, heavy, waxy, high resin) to be solved. The effect of the chemical composition of the oil on the number, distribution, and activity of reservoir microflora has been studied using data on the microbiological properties of reservoir water of 16 different fields in oil and gas basins of Russia, Mongolia, China, and Vietnam. Information on the physicochemical properties of crude oils of these fields has been obtained from the database created at the Institute of Petroleum Chemistry, Siberian Branch on the physicochemical properties of oils throughout the world. It has been found that formation water in viscous oil reservoirs is char acterized by a large population of heterotrophic and sulfate reducing bacteria and the water of oil fields with a high paraffin content, by population of denitrifying bacteria. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the knee kinematics of anterior cruciate ligament reconstructed (ACL-R) and healthy subjects (CG) during gait and classify the status of normality. Ten healthy and six ACL-R subjects had their gait analyzed at 60 fps. 3D knee angles were calculated and inserted into three separate matrices used to perform the principal component (PC) analysis. The scores of PCs retained in each analysis were used to calculate the standard distances (SD) of each participant in relation to the center of the CG. The PC scores of the three planes were used in a logistic regression to define normality. In the sagittal plane there was no difference between groups. In the frontal and transverse planes ACL-R subjects showed higher SD values than CG. PCs identified that ACL-R subjects showed increased adduction, internal and external rotation. All these subjects had their gait classified as abnormal by logistic regression. Therefore, in the studied ACL-R subjects the gait pattern did not return to normal levels after surgery. This may lead to degenerative injuries, as osteoarthritis, in the future. [ABSTRACT FROM PUBLISHER]

This paper presents a new intelligent robotic system to assist or guide visually impaired people in unknown indoor environments. The goal is to employ the robot public buildings such as hospitals, offices, etc. The robotic system, which is equipped with a visual sensor, laser range finders, speaker, gives visually impaired people information about the environment around them. The laser data are analyzed using the clustering technique, making it possible to detect obstacles, steps and stairs. In addition, the robot can be switched to the guide mode. By selecting the target location, the robot starts guiding the user toward the goal utilizing the line on the ground or evolved neural controllers. The PC analysis the sensors data and send information to the visually impaired people by natural language or beep signal. The usefulness of the proposed system is examined experimentally. [ABSTRACT FROM PUBLISHER]

In the recent past considerable research has been performed on blind signal detection techniques that exploit the covariance matrix of the signals received at a cognitive radio (CR). These techniques overcome the noise uncertainty problem of the energy detection (ED) method and can even perform better than ED for correlated signals. Contrary to the previous work where the main evaluation technique has been theoretical analysis and simulations, in this paper we use Software defined radios (SDRs) with correlated signal reception capability to evaluate the sensing performance of the existing covariance based detection (CBD) techniques. The existing techniques considered in this work are; Covariance absolute value (CAV), Maximum-minimum eigenvalue (MME), Energy with minimum eigenvalue (EME) and Maximum eigenvalue detection (MED). Most importantly this paper presents a novel technique for blind signal detection that uses Principal Component (PC) Analysis. The PC based signal detection algorithm and the CBD algorithms are tested in a real scenario with SDRs and their sensing performance is compared. The PC algorithm outperforms the MED and EME algorithms under all conditions and it performs better than the MME and CAV algorithms under certain conditions. [ABSTRACT FROM PUBLISHER]

Velvet bean (Mucuna pruriens [L.] DC.) is a tropical legume native to Africa and tropical Asia. In Indonesia, this plant is not widely cultivated, although, in some areas in Java, the community processed and fermented the pulse into a food called tempeh benguk. Besides being alternative for protein source, velvet bean can be used as herbal medicine. For decades, IAARD-ICABIOGRAD Gene Bank has been conserved the germplasm of velvet bean from some areas in Indonesia. However, morphological variability of the germplasm has not been reported. The research aimed to describes of phenotypic diversity among velvet bean accessions and focuses on morpho-agronomical characters. A total of 14 characters were observed from 9 accessions using plant descriptor. During the characterization, we found genetic mixture under the same accession. Therefore, we split these mixtures into different accession and assigned a new accession number for them, thus total accessions to be analyzed were 13 accessions. From clustering analysis, we found that these accessions were grouped into four clusters. Accession Koro Rawe Wonogiri was found to be the most distinct genotypes among accessions observed. Further comprehensive characterization should be conducted to reveal more information about diversity among velvet bean germplasm in IAARD-ICABIOGRAD Gene Bank. [ABSTRACT FROM AUTHOR]

Sodium-Ion Battery (SIB) is now having great attention instead of Lithium-Ion Battery (LIB) due to a high sodium abundance compare to lithium. Na-iron oxide compound mostly studied as raw material for SIB cathode. The abundance of iron source on earth is an advantage to develop SIB. Therefore, this research aims to prepare Fe2O3 from Indonesian iron sand through co-precipitation method, and then react the Fe2O3 with Na2O2 to produce NaFeO2. The reaction was conducted at 650 oC for 12 h. XRD analysis equipped with Le Bail refinement found that the prepared Fe2O3 has diffraction pattern similar to Fe2O3 ICSD#15840, trigonal structure and space group of R-3CH. Meanwhile, the prepared NaFeO2 has a diffraction pattern similar to standard diffraction ICSD#75588. The crystal structure is trigonal / rhombohedral with a space group of R-3MH. Test of NaFeO2 as a potential host for Mn2+ ions was conducted by doped 0.1 mol% Mn into NaFeO2. Cyclic voltammetry analysis of a half cell Na |NaFeO2| Al and Na |Mn doped-NaFeO2| Al shows an active electrochemical reduction-oxidation of Fe2+/Fe3+ at 1.776 V vs Na+/Na . Meanwhile a potential peak at 0.808 V released by NaFeO2 half-cell confirms the electrochemical activity of Na+ ions to leach out and inserted back into NaFeO2 cathode. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) has been applied to perform elemental analysis of printing ink samples. Samples of black printing inks from three types of printers viz. inkjet, laser-jet, and photocopier (three different brands for each type) and one control sample (blank white A4 paper) were analysed under optimised conditions. Results revealed that the LIBS method when coupled with PCA was able to provide discriminative evidence on elemental differences among all the different printing inks. Considering its time and cost effectiveness as well as requiring only minute amount of sample with no sample pre-treatment steps, the combination of LIBS and PCA may prove useful for forensic questioned document practical caseworks. [ABSTRACT FROM AUTHOR]

Alkaline soil additives used in this study, as cement kiln dust and lime mud, resulted in significant rise of the pH in contaminated soil and sludge mixtures, while buffering capacity of the sludge appeared to be much stronger than that of the soil. Total concentrations of the investigated trace elements in the tested samples in most cases were above limit values given in Lithuanian environmental normative documents HN 60:2015 and LAND 20:2005; Cd, Zn and Pb concentrations exceeding MPCs by 2-10 times. Nickel, cadmium and copper in the sludge appeared to be the most mobile elements, their EDTA-extractable fraction reaching 30-50% from the total. The tested industrial by-products in most cases significantly reduced trace element mobility. Immobilizing effect in the contaminated soil was from low to moderate, while impact on the reduction of Cd, Pb, Zn, Cr, Ni, As, Se, Hg mobility in the sludge was much stronger. Alkaline treatment was not so effective to reduce mobility of Cu and As in the soil, but immobilising effect of lime mud on these elements in the sludge was significant. A multivariate data analysis model with two principle components explained 94% of the data variation. The most distinctive factor, separating samples, was the origin of the two tested metal-rich substrates: contaminated soil and sewage sludge. Contaminated soil could be distinguished by high concentrations of As, Tl, Hg and Pb. Both alkaline treatments on sewage sludge were more effective, thus scores are further from the origin, although, difference between kiln dust and lime mud immobilising effectiveness was not so significant. Application of alkaline amendments: cement kiln dust and lime mud, proved to have strong immobilizing effect on the most of the investigated trace elements, and usage of local by-products for contaminated soil (sludge) remediation purposes could be seen as an environmentally friendly, cost-effective and safe disposal alternative. [ABSTRACT FROM AUTHOR]

This study introduces a system for forecasting wind power ramps developed via a national R&D project funded by the New Energy and Industrial Technology Development Organization. The developed forecast system focused on meteorological pattern analysis. First, the system evaluated the analogy between sea level pressure (SLP) patterns in the latest global-scale model and past SLP patterns associated with abrupt wind speed changes. The latest SLP pattern determined the selection of the optimal Weather Research and Forecast (WRF) model setup. Wind forecast data from the WRF model were corrected and converted to wind power output through the analog ensemble method and an empirical power curve. The forecast system also produced ramp probabilities and ramp alerts, which were calculated from the means and standard deviations of the wind power output on and around two transit locations (e.g., the starting time and after six hours) in the principal component space about the SLP forecast and power output observation data. [ABSTRACT FROM AUTHOR]

The experimental study results and PC analysis of microstrip hairpin filters on quarter-wave resonators are presented. Some recommendations to get optimum performance are given. [ABSTRACT FROM PUBLISHER]

Archaeological research based on traditional archaeological methods (typology, style and context analysis) provides a wealth of information concerning ware shape, color, decoration and overall fabric. In order to differentiate between such classificatory schemes, archaeologists often resort to an interdisciplinary approach involving the analysis of the mineralogical composition and geochemical fingerprints of the raw materials use in the pottery manufacture. The Cucuteni-Trypillia civilization developed during the V-IVth millennia BC and reached a very vast geographical area, with a total of more than 350,000 km2 in Romania, Ukraine and the Republic of Moldova. It is perhaps one of the most intriguing subjects when analyzing South-Eastern European prehistory. Its importance is not derived only from spectacular constructions and artifacts which include remains of multi-stage wattle-and-daub constructions, a wide variety of tools, diverse anthropomorphic and zoomorphic figures, and sophisticated polychrome pottery that have significantly enriched our knowledge of daily life and artistic handicraft of Old European civilizations. On the contrary, the Cucuteni-Trypillia civilization offer a diversified picture of the transformation in human social evolution and the role technological development assumes in bringing forth an early form of ranked social organization. This paper's aim is to investigate different pottery types selected from the Cucuteni culture eponymous site. X-ray diffraction (XRD) and environmental scanning electron microscope combined with energy diffraction analysis of X-rays (ESEM-EDX) analysis are the main techniques used in this paper to determine the technology and raw materials used in the pottery. Results show that the studied pottery samples can be divided into two main groups based on the nature and size of grains: shell-tempered pottery and pottery containing predominant fine quartz grains. This mineralogical distinction also reflects differences in production technology. [ABSTRACT FROM AUTHOR]