Miracle-dz/UniFAR-FTUs huggingface dataset:
Multiple Kernel k-Means With Low-Rank Neighborhood Kernel

Multiple kernel clustering algorithms achieve promising performances by exploring the complementary information from kernel matrices corresponding to each data view. Most of the existing methods aim to construct a consensus kernel for the afterward clustering. However, they ignore that the desired kernel is supposed to reveal the cluster structure among samples and thus to be low rank. As a consequence, the corresponding clustering performance could decrease. To address this issue, we propose a low-rank kernel learning approach for multiple kernel clustering. Specifically, instead of regularizing the consensus kernel with low-rank constraints, we use a re-parameterize scheme for the kernel matrix. Meanwhile, the consensus kernel is located in the neighborhood area of the linear combination of base kernels. An alternate optimization strategy is designed to solve the resulting optimization problem. We evaluate the proposed method on 13 benchmark datasets with 9 state-of-the-art algorithms. As is demonstrated by experimental results, our proposed algorithm achieves superior clustering scores against the compared algorithms on the reported popular multiple kernel datasets.
The Determination of Nitrite and Nitrate Ions by Differential Pulse Polarography

Abstract A previously reported method for the determination of nitrite ion has been extended to include nitrate ion. Nitrate is reduced to nitrite by a cadmium column and the nitrite ion determined as diphenylnitrosamine. Cadmium interference is removed by pH adjustment and the use of KDTA.
Improved Frequency-Domain Steady-State Modeling of the Dual-Active-Bridge Converter Considering Finite ZVS Transition Time Effects

This article presents an improved analytical modeling (IAM) approach for the dual-active-bridge (DAB) converter in the frequency-domain. Specifically, finite transition times are incorporated into the improved modeling that are significant in DAB converters operated at high frequency. The IAM approach is first motivated by comparing traditional frequency-domain modeling against realistic simulation results in LTspice. Next, the IAM approach is mathematically developed in an iterative fashion, where the conventional frequency-domain approach is used as the initialization of the operational behavior of the converter. Subsequent iterations of the IAM algorithm incorporate finite rise- and fall-times of device output capacitances based on detailed switching behavior analyses, which may considerably perturb the desired modulation parameters (i.e., phase shift and zero states). While the initially proposed IAM approach demonstrates advantages over ideal modeling, it is still shown to exhibit errors when applied to device transitions with significant nonlinearity in parasitic output capacitance. To account for this, a three-slope approximation to the switching transition is then motivated and developed, which enables significantly improved steady-state prediction accuracy. Simulation and experimental results confirm unacceptable inaccuracies associated with the conventional frequency-domain modeling across a wide range of operating conditions, alongside enhanced accuracy provided by the proposed modeling approach.
Genetic Diversity and Population Structure of Peanut (Arachis hypogaea L.) Accessions from Five Different Origins

Peanut is an allotetraploid derived from a single recent polyploidization. Polyploidization has been reported to have caused significant loss in genetic diversity during the domestication of cultivated peanuts. Single nucleotide polymorphism (SNP)-based markers such as cleaved amplified polymorphic sequences (CAPS) derived from next-generation sequencing (NGS) have been developed and widely applied for breeding and genetic research in peanuts. This study aimed to identify the genetic diversity and population structure using 30 CAPS markers and 96 peanut accessions from five different origins. High genetic dissimilarities were detected between the accessions from Korea and those from the other three South American origins generally regarded as the origin of peanuts, while the accessions from Brazil and Argentina presented the lowest genetic dissimilarity. Based on the results of the present study, accessions from Korea have unique genetic variation compared to those from other countries, while accessions from the other four origins are closely related. Our study identified the genetic differentiation in 96 peanut accessions from five different origins, and this study also showed the successful application of SNP information derived from re-sequencing based on NGS technology.
Impact of Attitudes Towards Entrepreneurship, Subjective Norms and Perceived Behavioral Control in Creating Entrepreneurial Intention

Many studies have discussed entrepreneurial intentions, but only a little research can be used as a reference in measuring the overall university in creating student entrepreneurial intentions in Indonesia. This research is focused on examining attitude toward entrepreneurship, subjective norms and perceived behavioral control by students in creating entrepreneurial intentions in the non-exact faculty of Brawijaya University. The data for this study were taken from 3 faculties, namely the Faculty of Administration, the Faculty of Social and Political Sciences and the Faculty of Economics and Business which are in Brawijaya University. The sample used in this study was 141 students. The results showed that attitudes towards entrepreneurship, and perceived behavioral control have a positive effect on entrepreneurial intentions. Only subjective norms have a not significant effect on entrepreneurial intentions. Keywords—attitudes toward entrepreneurship, subjective norms, perceived behavior control and entrepreneurship intentions
2-Ethyl-1,3-dioxo-2,3,3a,4,7,7a-hexahydro-1H-isoindole-4-carboxylic acid

The Diels–Alder cyclo­addition reactions between deactivated dienes and electron-deficient dienophiles are generally known to be thermodynamically disfavoured but when low solvent volumes were used for the reaction, the cyclo­addition of 4-(bromo­meth­yl)phenoxy­methyl polystyrene-bound (E)-1,3-butadiene-1-carboxylic acid with N-ethyl­maleimide gave the title compound, C11H13NO4, in good yield. The mol­ecules are connected through hydrogen bonds between the carboxyl group and one exocyclic carbonyl oxygen. The title compound is inter­esting in medicinal chemistry since related compounds are known to increase the blood platelet count in thrombocytopenia and to possess anti­convulsant activity.
Thirty years of leadership in New Zealand education: From the shadows of management to sine qua non

Abstract Leadership is now promoted as the sine qua non (essential ingredient) for maintaining and developing effective education in New Zealand. It was not this way in the latter years of the 1980s and through the 1990s, when educational management was the preferred nomenclature. Since the turn of the millennium, management has subsided into the shadows of leadership in New Zealand education as part of a global shift in the education policy lexicon and the Educational Management, Administration and Leadership (EMAL) field. Rather than argue whether leadership should be preferred over management, or vice versa, this article focuses on the rise of leadership in New Zealand education over the last 30 years.
In vitro engineering of transitional tissue by patterning and functional control of cells in fibrin gel

Tendon insertions show specific three-dimensional (3D) cell and matrix configurations. To fabricate this transitional tissue in vitro, the development of a cell manipulation technique that can control cell and matrix patterning in the 3D construct is crucial. Bone marrow-derived stromal cells and osteoblasts were respectively cultured in fibrin gel using a custom-made device that can apply uniaxial continuous tensile strain to the gel at different strain rates. Cells in the strained fibrin gel showed a specific orientation, which was parallel to the strain direction, because of the structural change of fibrin fibres within the strained gel. The direction of cell proliferation in the strained gel was also restricted to the same direction. Subsequently, linearly aligned cell sets, similar to the cell patterning of tendon tissue, were obtained in this culture system. Notably, linearly aligned extracellular matrix and mineral patterning, which are crucial for the fabrication of tendon insertions, were also confirmed in the strained fibrin gel. A cell proliferation assay indicated that the strained gel with a higher strain rate enhanced cell proliferation in the gel. In contrast, a Real-Time PCR study indicated that the strained gel with a lower strain rate enhanced cell differentiation in the gel. Thus, our new cell culture system enabled us to fabricate a 3D construct containing patterned cells and matrices in a controllable manner. This would be an effective tool for reproducing tendon insertions in vitro.
Hyperfine Sublevel Correlation (HYSCORE) Spectra for Paramagnetic Centers with Nuclear Spin I = 1 Having Isotropic Hyperfine Interactions†

Hyperfine sublevel correlation (HYSCORE) spectra of paramagnetic centers that have nuclei with nuclear spin I = 1 and isotropic hyperfine interactions (HFIs) and arbitrary nuclear quadrupole interactions (NQIs) are shown to consist of ridges that have zero width. A parametric presentation of these ridges is suggested that shows the range of possible frequencies in the HYSCORE spectrum and aids in spectral assignments and rapid estimation of spin Hamiltonian parameters. An alternative approach for the spectral density calculation is presented. This methodology is based on spectral decomposition of the Hamiltonian and requires only the eigenvalues. An atlas of HYSCORE spectra is given in the Supporting Information for this paper. This approach is applied to the estimation of the spin Hamiltonian parameters of the oxovanadium−EDTA complex.
A Study on Characterization and Use of Flotation to Separate Unburned Carbon in Bottom Ash from Çayirhan Power Plant

Abstract In this study, bottom ash from the Tuncbilek power plant has been characterized by X-ray fluorescence, X-ray diffraction, and infrared analysis. The bottom ash sample is potentially of class C type and has unburned carbon. The unburned carbon was separated from the bottom ash in a laboratory flotation cell. In the flotation experiment, sodium silicate (as a potential dispersant and depressant), butanol (promoter), kerosene oil (collector), and pine oil (frother) were used and the optimization of these flotation reagents were done through statistical modeling using a full two-level factorial design in order to evaluate the main and interaction effects of variables in flotation of unburned carbon; the evaluation of the results was done by Yates' notation. Test results showed that a product with 45.41% combustible grade at 40.0% recovery and 94.86% ash rejection was obtained at 1.98 g/kg sodium silicate, 1.38 g/kg promoter, 4.95 g/kg collector, and 2.41 g/kg frother.
SOLVENT EXTRACTION OF ALUMINIUM, GALLIUM AND INDIUM WITH 4-ACYL-3-PHENYL-5-1SOXAZOLONES

Abstract Five 4-acyl-3-phenyl-5-isoxazolones (AcyPI or HL) including three new compounds, 4-(4-toluoyl)-, 4-(4-fuluorobenzoyl)- and 4-(4-nitrobertzoyl(-3-phenyl-5-isoxazolones (TPI, FBPI and NBPI, respectively), were synthesized. The extraction of aluminium(III), gallium(IH) and indium (III) into benzene with the synthesized AcyPI has been investigated. The acid dissociation constants, Ka, and the partition coefficients, Kν, of AcyPI and the extraction constants, Kax, of their metal complexes were determined. The introduction of an electron-withdrawing fluoro or nitro group to the 4-position of the benzene ring in the acyl moiety of AcyPI was very effective for increasing the Kν. value of AcyPI, but scarcely affects the Kν value. The extracted species were ML3 in all the extraction systems, where M denotes the metal ion.
FPAES: A Hybrid Approach for the Optimal Placement and Sizing of Reactive Compensation in Distribution Grids

Reactive power compensation with Capacitor Banks (CBs) is one of the most successful approaches used in distribution systems, mainly due to their versatility, long-term acceptance in the power industry, and reduced costs. Most allocation methods, however, lack specific strategies to handle the limited discrete nature of CBs sizes seeking to improve the overall optimization and computational performance. We present an algorithm for the Optimal Placement of Capacitor Banks (OPCB) in distribution systems by means of a hybrid Flower Pollination Algorithm (FPA)–Exhaustive Search (ES) approach. The pollination process itself determines the sets of buses for placement, while CBs sizes and the final fitness values of each pollen are selected after a full-search is conducted in the sizing space. As the sizing phase works on the limited search space of predetermined discrete bank values, the computational effort to find the optimum CB capacity is greatly reduced. Tests were performed on distribution systems of 10, 34, and 85 buses with respect to the objective function, final losses, and voltage profile. The algorithm offers an excellent compromise between solution quality and computational effort, when compared to similar approaches.
Designing Secure User Authentication Protocol for Big Data Collection in IoT-Based Intelligent Transportation System

Secure access of the real-time data from the Internet-of-Things (IoT) smart devices (e.g., vehicles) by a legitimate external party (user) is an important security service for big data collection in the IoT-based intelligent transportation system (ITS). To deal with this important issue, we design a new three-factor user authentication scheme, called UAP-BCIoT, which relies on elliptic-curve cryptography (ECC). The mutual authentication between the user and an IoT device happens via the semitrusted cloud-gateway (CG) node in UAP-BCIoT. UAP-BCIoT supports several functionality features needed for IoT-based ITS environment including IoT smart device credential validation and big data analytics. A detailed security analysis is conducted based on the defined threat model to show that UAP-BCIoT is resilient against many known attacks. A thorough comparative study reveals that UAP-BCIoT supports better security, offers various functionality attributes, and also provides similar costs in communication as well computation as compared to other relevant schemes Finally, the practical demonstration of the proposed UAP-BCIoT is also provided to measure its impact on the network performance parameters.
Photophysical Properties of PS-2 Reaction Centers and a Discrepancy in Exciton Relaxation Times†

Exciton relaxation in the PS-2 reaction center of green plants is studied to explain a discrepancy of 2 orders of magnitude in certain relaxation times. Structural information from an earlier computer model and a recent low resolution structural study are combined with circular dichroism (CD) at 77 K, fluorescence line narrowing spectra at 1.6 K, and pump−probe spectra at 77 K to make predictions on the linear absorption spectrum at 77 K, fluorescence spectrum at 5 K, and absorption difference spectrum for modified pheophytin of the D_2 branch at 5 K. A width of the inhomogeneous distribution function of pigment energies of Δ_(inh) = 300 cm^(-1) and a mean vertical pigment transition energy corresponding to 669 nm are assumed for all pigments, based on the CD data, and a correlation radius of 5 A for the protein vibrations is deduced from the pump−probe data. The two peripheral chlorophylls resolved in a recent structure are calculated to give rise to optical dephasing times larger than 10 ps at wavelengths shorter than 670 nm, in agreement with dephasing times obtained in hole burning experiments. It is proposed, thereby, that the 2 orders of magnitude discrepancy between the fastest transfer times observed in hole burning and these in pump−probe experiments is due to the peripheral chlorophylls. Non-Markovian effects in the exciton-vibrational coupling are found to contribute significantly to optical line shape functions in the form of vibrational sidebands but to have minor influence on the relaxation dynamics of the excitons.
First-principles study of Cs and Sr sorption on carbon structures

Metal sorption on carbon plays an important role in a range of applications, including batteries, supercapacitors, and nuclear reactors. In particular, understanding sorption of radioactive isotopes, such as Cs and Sr in different graphite materials, is important for establishing nuclear reactor safety. This work uses ab initio methods to predict the binding behavior of Cs and Sr adatoms to perfect graphite, amorphous carbon, and diamond structures. The aim of these simulations is to analyze the influence of sp2 / sp3 binding and graphite defects on adatom binding strength. Results show a tendency of defects in graphite and carbon structures with sp3 bonds to form stronger bonds with the adatoms than perfect sp2 graphite. Comparison with experimental sorption data suggests that defects and sp3 bonded regions play a critical role in the sorption behavior of Cs and Sr on graphite.
Violent Conflict Exposure in Nigeria and Labor Supply of Farm Households

Nigeria has experienced bouts of violent conflict in different regions over the last few decades leading to significant loss of life. In this paper, we explore the potential short and accumulated long term effects of such conflict on labor supply of agricultural households. Using a nationally representative panel dataset for Nigeria in combination with armed conflict data, we estimate the effect of violent conflict on a farm household members labor supply. Our findings suggest that exposure to violent conflict significantly reduces the total number of hours the farm household head works and also deceases total family labor supply for agricultural households.
Analysis of phenolic acids and their antioxidant activity by capillary electrophoresis-mass spectrometry with field-amplified sample injection

In this study, a capillary electrophoresis-mass spectrometry (CE-MS) method with field-amplified sample stacking was developed to analyze and detect four hydrophilic active components (danshensu, salvianolic acid B, caffeic acid and lithospermic acid) present in many plant-derived samples, and to evaluate their antioxidant ability. The assay was performed on an uncoated fused-silica capillary of 95 cm × 50 μm I.D. and a positive voltage of 27 kV was applied. The sample was injected under pressure of 50 mbar for 3–300 s and the temperature of capillary was kept 25 °C. Sheath liquid constituted of 5 mM ammonium acetate in methanol solution, flowing at 4 μL min−1, and was supplied to the CE-electrospray interface. The effects of nebulizer gas pressure, the flow rate and temperature of the drying gas, sheath liquid composition and flow rate, and sample injection length were optimized in order to obtain better performance. Utilizing the preconcentration technique, the sensitivity was enhanced by approximately 30–50 fold in terms of limits of detection compared to common hydrodynamic injection without interference from matrix coextractives. The phenolic antioxidant abilities were also determined by simple and accurate free radical spiking test. Furthermore, the method has been successfully applied to a danshen sample.
Synthesis of Stacked-Cup Carbon Nanotubes in a Metal Free Low Temperature System

Stacked-cup carbon nanotubes were formed by either Fischer-Tropsch type or Haber Bosch type reactions in a metal free system. Graphite particles were used as the catalyst. The samples were heated at 600 C in a gas mixture of CO 75 Torr, N2 75 Torr and H2 550 Torr for three days. Trans mission electron microscope analysis of the catalyst surface at the completion of the experiment recognized the growth of nanotubes. They were 10-50 nm in diameter and approximately 1 micrometer in length. They had a hollow channel of 5-20 nm in the center. The nanotubes may have grown on graphite surfaces by the CO disproportionation reaction and the surface tension of the carbon nucleus may have determined the diameter. Although, generally, the diameter of a carbon nanotube depends on the size of the cataly1ic particles, the diameter of the nanotubes on graphite particles was independent of the particle size and significantly confined within a narrow range compared with that produced using catalytic amorphous iron-silicate nanoparticles. Therefore, they must have an unknown formation process that is different than the generally accepted mechanism.
Natural Language Processing for Forecasting Innovative Development of the Energy Infrastructure

The article deals with the application of natural language processing methods to support research and forecasting the innovative development of energy infrastructure. The main methods of NLP, which are used to build an intelligent system to support scientific research, are considered. Methods of building infrastructure for processing Open Linked Data and Big Data are described. Semantic analysis and knowledge integration are based on ontology system. Applying suggested methods allow increasing quality of scientific research in this area and make it more effectively
Real-Time Damping Estimation on Nonlinear Electromechanical Oscillation

Real-time damping estimation for a dominant inter-area mode is important for situational awareness of potential angular instability in power systems. Electromechanical oscillations energized by large disturbances often manifest obvious nonlinearities in measurements on first several swings. Traditional methods based on linear system theory often discard first several swings intentionally to avoid nonlinearity; if not, the estimated damping ratios often vary with the length and starting point of the measuring window. By identifying a nonlinear oscillator to fit a dominant mode, this paper proposes a new measurement-based approach utilizing complete post-disturbance data for robust damping estimation independent of the measuring window. Case studies on the IEEE 9-bus system and a 48-machine Northeast Power Coordinating Council system validate the proposed approach for providing accurate and robust damping estimation compared with existing methods including the Prony's method. Meanwhile, three factors influencing damping estimation in practical applications are also addressed, including measurement noises, limited coverage of PMU measurements, and existence of multiple dominant modes.
DC Capacitor Voltage Balance Control Method for High-Power Single-Phase Cascaded H-Bridge Rectifier to Extend the Regulation Range

Single-phase cascaded H-bridge rectifier (CHBR) plays an important role in high-speed trains. The dc capacitor voltage balance control is essential for a single-phase CHBR. However, existing dc capacitor voltage balance control methods suffer from lacking regulation range. To tackle this issue, a balance control method for dc capacitor voltage to extend the regulation range that is readily implemented is proposed in this article, whose regulation range is the widest. The steady-state operating region (SOR) of a single-phase CHBR is analyzed, and the operation loci of different methods in SOR are derived. According to the geometric relationship of operation loci, a simple method to evaluate the regulation range of different balance methods is introduced. Meanwhile, regulation ranges of different balance methods are compared based on this method, from which it can be known that the proposed dc capacitor voltage balance control method has the widest regulation range. Finally, experimental results verify the effectiveness and superiority of the proposed method.