bluuebunny/crossref_metadata_2025_split huggingface dataset:
Employment Effects of the 2009 Minimum Wage Increase: New Evidence from State-Based Comparisons of Workers by Skill Level
Authors: Hoffman Saul D. 
Published: January 2014

Abstract
In July, 2009, when the US Federal minimum wage was increased from $6.55 to $7.25, individuals in nearly one-third of all states were unaffected, since the state minimum wage already exceeded $7.25. We use this variation to make comparisons of the employment of low-skill workers with their peers across states and with workers within states who were arguably unaffected by the increase, using DID and DIDID methods. Our data come from the 2009 Current Population Survey, 4 and 5 months before and after the increase. We find little evidence of negative employment effects for teens or less-educated adults. Further control for demographic characteristics and state fixed effects have relatively small effects on the size and significance of estimated effects.
Graded quiver varieties and derived categories
Authors: Keller Bernhard , Scherotzke Sarah 
Published: January 2014

Abstract
Inspired by recent work of Hernandez–Leclerc and
Leclerc–Plamondon we investigate the link between Nakajima's graded
affine quiver varieties associated with an acyclic connected quiver Q and the
derived category of Q. As Leclerc–Plamondon have shown,
the points of these varieties can be interpreted
as representations of a category, which we call the (singular) Nakajima
category 𝒮. We determine the quiver of 𝒮
and the number of minimal relations between any two given vertices.
We construct a δ-functor Φ taking each finite-dimensional
representation of 𝒮 to an object of the derived category of Q.
We show that the functor Φ establishes a bijection between the strata of the
graded affine quiver varieties and the isomorphism classes of objects
in the image of Φ. If the underlying graph of Q is an ADE Dynkin
diagram, the image is the whole derived category; otherwise, it is
the category of `line bundles over the non-commutative curve given by Q'.
We show that the degeneration order between
strata corresponds to Jensen–Su–Zimmermann's degeneration
order on objects of the derived category. Moreover, if Q is an ADE Dynkin quiver,
the singular category 𝒮 is weakly Gorenstein of dimension 1 and its
derived category of singularities is equivalent to the derived category of Q.
Assessment of Heat Transfer and Mass Change During Fruits and Vegetables Impingement Pre-Cooling
Authors: Góral Dariusz , Kluza Franciszek , Kozłowicz Katarzyna 
Published: January 2014

Abstract
The study investigated the use of impingement methods for cooling of fruits and vegetables. Raw materials were cooled in air at 0°C temperature flowing from nozzles of 0.02 m diameter with speed in the range of 10–51 ms−1 and for comparing, in the water at the same temperature. Raw mass change, value of heat transfer coefficient in the system and the cooling time were analyzed. The mass losses are dependent on air velocity at the nozzles exit, increase in the cooling air velocity permits a reduction in the losses. The mean value of heat transfer coefficient were found within the 12–44 W(m2 K)−1 range. It was found that the impingement method can be used for rapid cooling of fruits and vegetables, characterizing the process parameters comparable to the cooling of water.
Research on design rules for composite laminate
Authors: Wang Gong-Dong , Wang Jun , Hossain Sayed K.M. , Chen Hao 
Published: January 2014

AbstractA methodology of laminate design rules is proposed to incorporate constraint in genetic algorithm (GA). It can provide optimization result that conforms to the composite design rules. Several methods such as replacement approach, swap approach, combined approach, and zero fitness approach are introduced to execute the laminate design rules concept. Effects are analyzed in terms of fitness value and convergence rate. Using rule operators, the convergence speed of the GA is increased. The proposed solutions will be more suitable than standard GA for some particular application with their conformance to the design rules. As a result, these methods are successfully applied and a practical optimal stacking sequence is obtained with the most appropriate for design rules.
Dopamine-Modulated Recurrent Corticoefferent Feedback in Primary Sensory Cortex Promotes Detection of Behaviorally Relevant Stimuli
Authors: Happel Max F. K. , Deliano Matthias , Handschuh Juliane , Ohl Frank W. 
Published: January 2014

Dopaminergic neurotransmission in primary auditory cortex (AI) has been shown to be involved in learning and memory functions. Moreover, dopaminergic projections and D1/D5receptor distributions display a layer-dependent organization, suggesting specific functions in the cortical circuitry. However, the circuit effects of dopaminergic neurotransmission in sensory cortex and their possible roles in perception, learning, and memory are largely unknown.Here, we investigated layer-specific circuit effects of dopaminergic neuromodulation using current source density (CSD) analysis in AI of Mongolian gerbils. Pharmacological stimulation of D1/D5receptors increased auditory-evoked synaptic currents in infragranular layers, prolonging local thalamocortical input via positive feedback between infragranular output and granular input. Subsequently, dopamine promoted sustained cortical activation by prolonged recruitment of long-range corticocortical networks. A detailed circuit analysis combining layer-specific intracortical microstimulation (ICMS), CSD analysis, and pharmacological cortical silencing revealed that cross-laminar feedback enhanced by dopamine relied on a positive, fast-acting recurrent corticoefferent loop, most likely relayed via local thalamic circuits. Behavioral signal detection analysis further showed that activation of corticoefferent output by infragranular ICMS, which mimicked auditory activation under dopaminergic influence, was most effective in eliciting a behaviorally detectable signal.Our results show that D1/D5-mediated dopaminergic modulation in sensory cortex regulates positive recurrent corticoefferent feedback, which enhances states of high, persistent activity in sensory cortex evoked by behaviorally relevant stimuli. In boosting horizontal network interactions, this potentially promotes the readout of task-related information from cortical synapses and improves behavioral stimulus detection.
Heteroscedastic Ridge Regression Approaches for Genome-Wide Prediction With a Focus on Computational Efficiency and Accurate Effect Estimation
Authors: Hofheinz Nina , Frisch Matthias 
Published: January 2014

Abstract
Ridge regression with heteroscedastic marker variances provides an alternative to Bayesian genome-wide prediction methods. Our objectives were to suggest new methods to determine marker-specific shrinkage factors for heteroscedastic ridge regression and to investigate their properties with respect to computational efficiency and accuracy of estimated effects. We analyzed published data sets of maize, wheat, and sugar beet as well as simulated data with the new methods. Ridge regression with shrinkage factors that were proportional to single-marker analysis of variance estimates of variance components (i.e., RRWA) was the fastest method. It required computation times of less than 1 sec for medium-sized data sets, which have dimensions that are common in plant breeding. A modification of the expectation-maximization algorithm that yields heteroscedastic marker variances (i.e., RMLV) resulted in the most accurate marker effect estimates. It outperformed the homoscedastic ridge regression approach for best linear unbiased prediction in particular for situations with high marker density and strong linkage disequilibrium along the chromosomes, a situation that occurs often in plant breeding populations. We conclude that the RRWA and RMLV approaches provide alternatives to the commonly used Bayesian methods, in particular for applications in which computational feasibility or accuracy of effect estimates are important, such as detection or functional analysis of genes or planning crosses.
Precursor concentration effect on structure and morphology of ZnO for coatings on fabric substrates
Authors: Suchea M. , Tudose I.V. , Vrînceanu N. , Istrate B. , Munteanu C. , Koudoumas E. 
Published: January 2014

Abstract
ZnO is a versatile functional material that has a diverse group of growth morphologies. By controlling the growth kinetics, it is possible to change the growth behavior of ZnO structures. Growth of ZnO structures can be achieved in a cheaper way at low temperature using chemical growth techniques such as aqueous chemical growth, nonaqueous solution growth, sol gel and spray deposition. Up to date, there are quite few reports in the literature presenting state of art approaches of use of ZnO material onto textile substrates for several applications as antibacterial, deodorizing and UV protection, and none regarding any systematic approach of direct growth and optimization with respect to the textile support. The successful exploitation of ZnO particles for use in various technological applications requires the development of techniques for controlling its photocatalytic activity. The present contribution presents a study of precursor concentration effect on structure and morphology of ZnO for coatings on fabric substrates. ZnO particles were obtained by direct growth onto the respective substrate by aqueous chemical growth using suitable precursors for each growth and then characterized regarding their appearance, size and structure using microscopic techniques and X-ray diffraction.
Development and evaluation of coenzyme Q10 loaded solid lipid nanoparticle hydrogel for enhanced dermal delivery
Authors: Korkm Emrah , Gokce Evren H. , Ozer Ozgen 
Published: January 2014

Abstract
Coenzyme Q10 (Q10) loaded solid lipid nanoparticles (SLN) were prepared by the high speed homogenization method and incorporated into Carbopol 974P hydrogels. Compritol 888 ATO (C888) was employed as the lipid base; Poloxamer 188 (P188) and Tween 80 (Tw80) were used as surfactant and co-surfactant. Optimum particle size with narrow distribution was obtained as 152.2 nm for blank and 142.4 nm for Q10 loaded SLNs. The overall charge of loaded SLNs was -13.7 ± 1.3 mV. Q10 entrapment efficiency was 89 % and the production yield was 94 %. Transmission electron microscopy analysis provided evidence of colloidal size, spherical shape while differential scanning calorimetry analysis confirmed recrystallization of the lipid after the preparation of SLNs. Trolox equivalent antioxidant capacity (TEAC) analysis has shown that antioxidant potential of Q10 can be protected in SLNs. Rheological characteristics demonstrated that the SLN incorporating gels were shear thinning and the mechanical strength of the gels was suitable for topical application. Diffusion studies from rat abdominal skin revealed that the delivery of Q10 was doubled in SLN incorporating gels, approximately 40 μg cm-2, in comparison with gels prepared with only Q10 (not incorporated in SLNs). As a result, it can be stated that Q10-SLN loaded gels can be successful delivery systems for carrying Q10 efficiently into the skin without losing its antioxidant properties.
CLINCHRIVET AS AN ALTERNATIVE METHOD TO RESISTANCE SPOT WELDING
Authors: Kaščák Ľuboš , Spišák Emil , Mucha Jacek 
Published: January 2014

Abstract
Various materials are used in car body production which are not always possible to join by conventional joining methods such as resistance spot welding. Therefore ClinchRivet method seem to be possible alternative. The paper deals with evaluation of properties of the joints made by mechanical joining method - ClinchRivet. The joint is made with the using of a special rivet, which is pushed into the joined materials by the flat punch. Following materials were used for joining of this method: DX51D+Z and H220PD steel sheets. The tensile test for observing the carrying capacities and metallographicall analysis were used for the evaluation of joint properties. Some results of the tests of ClinchRivet joints were compared to the properties of the joints made by resistance spot welding.
The Microstructures and Energy Dispersive Spectroscopy Analysis of a Hypoeutectoid Steels With 1% Cr
Authors: Rożniata E. 
Published: January 2014

Abstract
The results of a microstructure, Energy Dispersive Spectroscopy analysis and hardness investigations of the hypoeutectoid steels with 1% Cr, imitating by its chemical composition toughening steels, are presented in the paper. Dilatometric tests were performed using L78R.I.T.A dilatometer of the German company LINSEIS. Using dilatometer the changes of elongation (Δl) of the samples with dimensions φ 3X10mm as a function of temperature (T) were registered. Obtained heating curves were used to precisely determine the critical temperatures (critical points) for the tested steels, while the differentiation of obtained cooling curves allowed to precisely define the temperatures of the beginning and the end of particular transition to draw two CCT diagrams. The analysis of the chemical composition of the phases present in the studied steels for different cooling rates were performed using an electron microprobe (X-ray microanalyzer). In this study a point, linear and a fixed area analysis techniques were used. After placing the samples tested steels in the chamber and the achievement of appropriate vacuum, spots for analysis were identified and the EDS analysis (Energy Dispersive Spectroscopy) was performed. EDS analyzes were performed using Nova NanoSEM 450 scanning electron transmission microscope. Developed CCT diagrams in accordance with the Rose and Wever classification are of type IV, which means that the diffusional transformations are separated by a stability range of the undercooled austenite and have the shape of the letter ”C”. The hardenability of tested steels is similar, but molybdenum acts much more effectively than nickel. Molybdenum occupies the I-st place among the effectiveness of alloying elements for the steels designed for low tempering, where the ”background” of other elements is weak. For both tested hypoeutectoid steels an EDS analysis revealed the precipitation of alloyed cementite at the grain boundaries. Chromium, as a ferrite creative element, quite strongly diffuses into the grain boundaries. It is visible with the change of chromium distribution along pearlite/ferrite grains boundaries.
Cross wedge rolling with upsetting
Authors: Tofil A. , Tomczak J. , Pater Z. 
Published: January 2014

Abstract
The paper describes cross wedge rolling with upsetting, a process in which axially symmetric parts with steps whose diameters are larger than billet diameters can be formed. Taking advantage of numerical modeling, the effect of such basic geometric parameters of the rolling process as the spreading angle, forming angle, reduction ratio, and rolling length on upsetting (defined by the diameter increase ratio) was determined. The paper also presents the results of experimental tests performed to roll a stepped shaft whose one step had a diameter half as large as that of the billet.
Composite Ag-La0.8Sr0.2MnO3-σ Cathode for Solid Oxide Fuel Cells
Authors: Mosiałek M. , Przybyła M. , Tatko M. , Nowak P. , Dudek M. , Zimowska M. 
Published: January 2014

Abstract
Composite cathodes for solid oxide fuel cells composed of metallic silver dispersed in ceramic (La0:8Sr0:2MnO3-σ) matrix were prepared on the surface of solid electrolyte by two-step procedure. First the matrix of controlled porosity was created by sintering mixture of La0:8Sr0:2MnO3-σ powder with the organic polymer beads then the matrix was saturated with AgNO3 solution and sintered again. Such obtained cathodes showed higher electrical conductivity and lower charge transfer resistance in oxygen reduction reaction in comparison to pure ceramic cathodes
Application of a Preisach Hysteresis Model to the Evaluation of PMN-PT Ceramics Properties
Authors: Wawrzała P. 
Published: January 2014

Abstract
The work presents enhanced, relatively new iterative method for obtaining the classical Preisach distribution from a single, saturated hysteresis loop. As the material for research and analysis, the ceramic solid solution (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (x = 0 to 0.40) was selected. Distributions were obtained for (1-x)PMN-xPT ceramics as a function of PT content, and function of temperature, for a selected composition from the morphotropic phase boundary region. The paper also proposes a mathematical model of the Preisach distribution and the parameters of the distribution were calculated. The typical factors achievable directly from the hysteresis loop with a coefficients determined from the analytical Preisach model were compared.
Study of Phase and Chemical Composition of Bi1-xNdxFeO3 Powders Derived by Pressureless Sintering
Authors: Dzik J. , Lisinska-Czekaj A. , Zarycka A. , Czekaj D. 
Published: January 2014

Abstract
In the present paper studies on Bi1-xNdxFeO3 for x =0.1-0.4 are reported. The mixed oxide method followed with pressureless sintering was employed for ceramics fabrication. Thermal behavior of stoichiometric mixtures of simple oxide powders, viz. Bi2O3, Nd2O3 and Fe2O3 was studied by simultaneous thermal analysis. It was found that with an increase in neodymium content the weight loss increased from 0.75% to 3.16% for x =0.1 and x =0.4, respectively. It was found that weight loss took place mainly within two temperature ranges, namely ΔT1 ≈(300-400)0C and ΔT2 ≈(600-800)°C. Bi1-xNdxFeO3 ceramics was studied in terms of its phase composition (X-ray phase analysis) and chemical composition (EDS method) at room temperature. It was found that Bi1-xNdxFeO3 suffered structural phase transition from rhombohedral to orthorhombic symmetry with an increase in neodymium concentration x within the range x =(0.2-0.3).
Modeling of Mechanical Influence of Double-Beam Laser on Single-Crystalline Silicon
Authors: Shalupaev S.V. , Serdyukov A.N. , Mityurich G.S. , Aleksiejuk M. , Nikitjuk Y.V. , Sereda A.A. 
Published: January 2014

Abstract
The results of finite-element modeling of controlled laser thermosplitting of crystalline silicon are presented. The case of treatment by two laser beam with wavelengths, namely 0.808 μm and 1.06 μm is studied. Calculations of the thermoelastic fields formed in a single-crystalline silicon wafer as a result of consecutive two-beam laser heating and action of coolant were performed for silicon crystalline orientations: (100), (110), (111). Modeling was performed for circular and U-shaped laser beams. The results received in the presented work, can be used for the process optimization concerning the precise separation of silicon wafers by laser cutting.
ON THE EFFECTS OF MACERAL CONTENT ON METHANE SORPTION CAPACITY IN COALS / WPŁYW ZAWARTOŚCI MACERAŁÓW NA POJEMNOŚĆ SORPCYJNĄ METANU W WĘGLACH
Authors: Olajossy Andrzej 
Published: January 2014

Abstract
The problems connected with the sorption capacity of methane in hard coals are constantly subject to various research. In this paper, the influence of the content of macerals mainly vitrinite for the sorption capacity of chosen samples of Polish hard coals was analysed. The analysis was conducted on basis of available from the literature results of resarches of petrographic composition of this coals and methane sorption isotherms. The samples of grained coals contained from 7 ro 76% of vitrinite and their sorption capacity was obtained in the scope of high pressures; 0 < p < 80 bars, on the basis of the equation of Langmuire. In effect, it turned out that the maceral content has a little influence on the methane sorption capacity of coals. This refers mainly to high volatile and middle volatile coals. In the literature concerning this issue simillar effect may be encountered for other coals.
Selection of the air heat exchanger operating in a gas turbine air bottoming cycle
Authors: Chmielniak Tadeusz , Czaja Daniel , Lepszy Sebastian 
Published: January 2014

Abstract
A gas turbine air bottoming cycle consists of a gas turbine unit and the air turbine part. The air part includes a compressor, air expander and air heat exchanger. The air heat exchanger couples the gas turbine to the air cycle. Due to the low specific heat of air and of the gas turbine exhaust gases, the air heat exchanger features a considerable size. The bigger the air heat exchanger, the higher its effectiveness, which results in the improvement of the efficiency of the gas turbine air bottoming cycle. On the other hand, a device with large dimensions weighs more, which may limit its use in specific locations, such as oil platforms. The thermodynamic calculations of the air heat exchanger and a preliminary selection of the device are presented. The installation used in the calculation process is a plate heat exchanger, which is characterized by a smaller size and lower values of the pressure drop compared to the shell and tube heat exchanger. Structurally, this type of the heat exchanger is quite similar to the gas turbine regenerator. The method on which the calculation procedure may be based for real installations is also presented, which have to satisfy the economic criteria of financial profitability and cost-effectiveness apart from the thermodynamic criteria.
Thermodynamic and economic analysis of a gas turbine combined cycle plant with oxy-combustion
Authors: Kotowicz Janusz , Job Marcin 
Published: January 2014

Abstract
This paper presents a gas turbine combined cycle plant with oxy-combustion and carbon dioxide capture. A gas turbine part of the unit with the operating parameters is presented. The methodology and results of optimization by the means of a genetic algorithm for the steam parts in three variants of the plant are shown. The variants of the plant differ by the heat recovery steam generator (HRSG) construction: the singlepressure HRSG (1P), the double-pressure HRSG with reheating (2PR), and the triple-pressure HRSG with reheating (3PR). For obtained results in all variants an economic evaluation was performed. The break-even prices of electricity were determined and the sensitivity analysis to the most significant economic factors were performed.
A physico-chemical study for some edible oils properties
Authors: Neagu Anişoara-Arleziana , Niţa Irina , Botez Elisabeta , Geaca Sibel 
Published: January 2014

AbstractIn the present paper we have experimentally determined the density, saponification value, iodine value, acid value, peroxide value for four different edible oils: sunflower oil, corn oil, rapeseed oil and peanut oil. Density was determined in the temperature range of 20 °C - 50 °C, with a 10 degree step increase. The physicochemical properties of the investigated oils were within the requirements of food domain: saponification value varied from 164.84 to 206.45 mg KOH/g, peroxide value varied from 9.99 to 24.49 mEg O2/kg of sample, acid value varied from 0.22 to 3.97 mg KOH/g, iodine value varied from 94.35 to 102.02 g I2/100 g sample, and density varied from 0.9031 to 0.9208 g/cm3. Based on experimental data, density were correlated with others properties of edible oils. An empirical model was proposed to correlate oil density with iodine value and temperature. The results of the proposed model were compared with a model from literature. The accuracy of the proposed model was very good, the AAD varying in the range of 0.078 % to 0.092 %. The proposed model can be recommended for density of vegetable oils evaluation based on their IV, at different temperatures in the range of 20 °C to 50°C.