bluuebunny/crossref_metadata_2025 huggingface dataset:
ANALYSIS OF METHODS USING FOR SUPERRESOLUTION OF THE SIGNALS IN THE TASKS OF SPACE-TIME ACCESS
Authors: Moskalets Mykola , Teplytska Svitlana
Published: September 2016

Six methods are considered in the analysis of the methods of angular superresolution of the signals: non-adaptive beamforming, Kapon, thermal noise, Bordzhotti-Lagunas, maximal entropy and multiple signal classification (MUSIC). The comparative characteristic of the methods with assessing their advantages disadvantages and limitations is given. Theoretical resolution of these methods is assessed in the article.

Numerical evaluation of resolution ability of the methods of angular superresolution of the signal are obtained based on the simulation of various scenarios of signal-to-noise ratio, taking into account the use of correlated and uncorrelated signals, a different number of antenna elements and the values of the signal / interference + noise ratio. These estimations show the ultimate theoretical accuracy of the methods and the potential for their use in problems of space-time access with set limits.

The simulation results confirmed the statistical consistency of these methods of estimation of arrival direction angles of correlated and uncorrelated signals from subscriber stations for the space-time sampling in the output of the linear equidistant antenna array.

The present analysis and research results make it possible to select the most effective method for determining the arrival of signals in accordance with the given parameters of signal-to-noise ratio under restrictions.
INVESTIGATION OF STRESS-STRAIN STATE OF TRANSVERSELY ISOTROPIC PLATES UNDER BENDING USING EQUATION OF STATICS {1,2} –APPROXIMATION
Authors: Bokov Igor , Bondarenko Natalia , Strelnikova Elena
Published: September 2016

The study examined the construction of the fundamental solution for the equations of statics {1,2} – approximation for transversely isotropic plates under bending with the action of concentrated force. Equations {1,2} -approximation were obtained by the decomposition method in the thickness coordinate using the Legendre polynomials. These equations take into account all the components of the stress tensor, including the transverse shear and normal stresses. Since the classical theory of Kirchhoff-Love doesn’t take account of these stresses, the study on the basis of refined theories of stress-strain state of transversely isotropic plates under the action of concentrated force effects is an important scientific and technical problem.

The fundamental solution of obtained equations results using a two-dimensional Fourier integral transform and inverse treatment techniques, built with the help of a special G-function. This method allows reducing the system of resolving differential equations for statics of flat plates and shells to a system of algebraic equations. After that, the inverse Fourier transform restores the fundamental solution. The work was carried out numerical studies that demonstrate patterns of behavior of components of the stress-strain state, depending on the elastic constants of transversely isotropic material. The results play a decisive role in the study of boundary value problems in the mechanics of thin-walled elements of constructions, including under the influence of concentrated and local diverse forces.
Acoustic analysis and characterization of Indian musical instrument: Ghumot
Authors: Akshay Sundar , Hancel P. V. , Pravin Singru , Radhika Vathsan
Published: September 2016

The study conducted was to characterize the acoustic features and spectrum of the Ghumot, a membranophone type musical instrument indigenous to Western India. This instrument is part of the dying culture of Goan traditional music; hence it has been studied to give it a scientific understanding. The instrument was played with both conditions of the resonance cavity taken into account (open and closed), and the frequency domain spectra were determined for each. The variation in the acoustics characteristics of the instrument was plotted according to position of impact and position of measurement. The Ghumot membrane displayed non-linear characteristics as compared to a uniform, isotropic circular membrane. A comparative study was also made for the Ghumot and the Tabla to determine the number of unique tones or ‘bols’ that the instrument can produce.
Sun sensor design and test of a micro satellite
Authors: Lin Li , Sitong Zhou , Luyang Tan , Dong Wang
Published: September 2016

According to the requirement of small satellite, this paper designed a digital sun sensor which diaphragm is a V-shaped cross-section structure. Using Position Sensitive Detector (PSD) as the light detector, we designed the V-shaped cross-section structure based on the pinhole imaging principle. The sun sensor realized the accurate calculation for two axis sun angle of the sun sensor. The mechanical test, thermal test and testing of the sun sensor are designed and carried out. The mechanical test and thermal test results verify the stability of the sun sensor. Testing result shows that the detection angle can reach (120°)×(120°), and the attitude determination accuracy is better than 6” in the entire viewing field. The mass, volume and power consumption of the sun sensor is 0.177 kg, 78 mm×77 mm×21 mm and 0.25 W. The sun sensor has low power consumption, large viewing angle and high precision characteristics, which realized the sun sensor the miniaturization and meet the requirements of the micro satellite. Its performance has been verified in orbit.
Measurement of large amplitude plane vibrations of two dimensional structures
Authors: Maskeliūnas V. , Maskeliūnas R. , Pauliukas A. , Ragulskis L.
Published: September 2016

In the paper large amplitude plane vibrations of an elastic structure are investigated experimentally by using the method of time averaged geometric moiré. Investigations of a two-dimensional problem are performed. Experimental setup is developed and the results obtained by using the experimental procedure are analyzed. On the basis of a one-dimensional model graphical relationships for linear variation with respect to longitudinal coordinate of amplitude of vibrations are obtained. They provide the background for interpretation of partially exposed time averaged moiré. Recommendations for the choice of background intensity are provided.
Design and realization of virtual prototype of shotcrete robot based on OpenGL
Authors: Zhong Pei-si , Zheng Yi , Liu Kun-hua
Published: September 2016

This paper introduces a novel design method of virtual prototype based on OpenGL. This method can be applied to describe the principle of work and show the operating condition of the robot, plays a significant role in promoting structural design and system optimization of the robot. And in this way with CAD modeling and VC++ programming techniques developed a kind of virtual prototype system of PJR-2X shotcrete robot, solved the issue of the establishment of the complex model based on OpenGL
Straight-line path following for asymmetric unmanned platform with disturbance estimation
Authors: Hua Yu-long , Zheng Xiao-zhou , Chi Bao-shan , Sun Wei
Published: September 2016

The problem of straight-line path following for asymmetric unmanned platform exposed to unknown disturbances was addressed in this paper. The mathematical model of asymmetric unmanned platform was established and the inputs in sway and yaw directions were decoupled, which facilitated the establishment of control strategy of path following. The guidance law and the cross-track error were derived from the classical line-of-sight (LOS) guidance principle. And the equilibrium point of the cross-track error was proven to be uniformly semiglobally exponentially stable (USGES), which guaranteed the exponential convergence to zero. A new disturbance estimation law was developed by adding a linear item of the estimation error into the classical one, which improved the principle’s precision and sensitivity dramatically. The control strategy was developed based on the integrator backstepping technique and the new disturbance estimation law, which made the equilibrium system to be uniformly globally asymptotically stable (UGAS). Computer simulations were conducted to verify the effectiveness of the estimation and control laws during straight-line path following for asymmetric unmanned platform in the presence of unknown disturbances.
Double-layer vibration suppression bilinear system featuring electro-rheological damper with optimal damping and semi-active control
Authors: Gao Xinke , Fan Ganglong , Chen Jin , Dong Guangming
Published: September 2016

Based on the analysis of a double-layer vibration suppression bilinear system, the limitation of the classic passive vibration suppression technology was solved in case of relatively complex input force mixed signals. Using the maximum value principle and the constrained gradient method, the optimal damping semi-active control (ODSAC) curve of this system model was obtained. Due to the strong nonlinear characteristics of the controlling curve and even a non-derivable problem being existed, a pulse function was introduced, and a theoretic deduction was performed. The defects, that a curve with non-derivable points could not be solved, were overcome so that the proposed method was applicable to a bilinear system model. The stability of the controller was discussed in detail. Finally, the effects of the vibration suppression of the ODSAC method were compared with that of the passive damping system and that of the semi-active skyhook damping system under the excitation of the mix signal of single-frequency sine and pulse input signal, the mix signal of random and sine signal, the mix signal of random and impact input signal. The experiments of electro-rheological fluid (ERF) damper with single damping duct and simulation results show that the ODSAC strategy of a double-layer vibration suppression bilinear system is the best of the five kinds of vibration suppression effect of control strategies, and the vibration reduction effect with respect to the random and shock input mixed signal is remarkable, the vibration suppression effect of the new method is satisfactory.
An improved Fourier series method for vibration analysis of moderately thick annular and circular sector plates subjected to elastic boundary conditions
Authors: Ahad Fazl e , Shi Dongyan , Hina Zarnab , Aftab Syed M. , Waqas Hafiz M.
Published: September 2016

In this paper, an improved Fourier series method is presented for vibration analysis of moderately thick annular and circular sector plates subjected to general elastic boundary conditions along its edges. In literature, annular and circular sector plates subjected to classical boundary conditions have been studied in detail however in practical engineering applications the boundary conditions are not always classical in nature. Therefore, study of vibration response of these plates subjected to general elastic boundary conditions is far needed. In the method presented, artificial boundary spring technique has been employed to simulate the general elastic boundary conditions and first order shear deformation theory has been employed to formulate the theoretical model. Irrespective of the boundary conditions, each of the displacement function is expressed as a new form of trigonometric expansion with accelerated convergence. Rayleigh-Ritz method has been employed to determine the expansion coefficients. Unlike most of the studies on vibration analysis of moderately thick annular sector plates, the present method can be universally applied to a wide range of vibration problems involving different boundary conditions, varying material and geometric properties without modifying the solution algorithms and procedure. The effectiveness, reliability and accuracy of the present method is fully demonstrated and verified by several numerical examples. Bench mark solutions for moderately thick annular sector and circular plates under general elastic boundary conditions are also presented for future computational methods.
A novel failure analysis and diagnosis method for hydraulic-turbine generator unit
Authors: Xia Xin , Ni Wei
Published: September 2016

The failure analysis and diagnosis of hydraulic-turbine generator unit (HGU) is important to protect the safety and stability of the electric system. But failure analysis and diagnosis for HGU is lacking of fault data, and most of the failure analysis and diagnosis methods are proposed without considering the characteristic of HGU. In this paper, a vibration dynamic modeling method for HGU is proposed by using the finite element method, and further the vibration data in different states are getting through numerical simulation. Then, the failure feature is extracted based on the nonlinear output frequency response functions (NOFRFs). Finally, a diagnosis system with Support Vector Machine (SVM) is proposed and employed for diagnosis of the HGU. The experimental results indicate that the feature which extracted from NOFRFs has a strong effect, and demonstrates that the proposed method is feasible and helpful for fault diagnosis in HGU.
Finite element analysis of smart wind turbine blades sandwiched with magnetorheological fluid
Authors: Wang Hao , Fan Haizhe , Han Chunhui , Li Shuaibin
Published: September 2016

A brand-new smart wind turbine blade with magnetorheological fluid (MRF) sandwiched was proposed in the research. The three-dimension entity model of a 750 KW wind turbine blades was established through the use of UG software, and three kinds of MRF sandwich layouts were considered into the blade model, that is, at the blade tip, at the blade root and at the whole blade from the root till the tip. The MRF was simplified as Kelvin-Voigt model in order to implement the finite element analysis based on ANSYS software, so that the mode shapes of smart wind turbine blade were revealed under various conditions with three different layout forms of MRF sandwich wind turbine blades. Analysis results showed that the magnetic field would influence the mode shapes of the wind turbine blade with MRF sandwiched, especially the torsion vibration. When the MRF was inserted through the blade from the root till the tip, the blade would dramatically influence the torsion vibration, so that the torsion vibration, which originally would have happened at higher orders, would arise in advance. While the MRF was located at the root of wind turbine blade, the torsion vibration would be postponed to arise at the higher orders. Therefore, the MRF should be located at the blade root, instead of the middle and the tip of wind turbine blade. Smart sandwich wind turbine blade will provide a new way to the vibration control of wind turbine blade.
Large amplitude free vibrations of simply supported moderately thick rectangular plates using coupled displacement field method
Authors: Bhaskar K Krishna , Saheb K Meera
Published: September 2016

In this paper a novel method known as Coupled Displacement Field Method was proposed to evaluate the large amplitude free vibration behavior of the moderately thick rectangular plates with simply supported boundary conditions. Here a single term trigonometric admissible displacement field was assumed for one of the variables, say the total rotations (in both X, Y directions). With the help of the coupling equations, the spatial variation for the lateral displacement field is derived in terms of the total rotations, where the two independent variables problem becomes one. The coupled displacement field method makes use of the energy formulation which contains half the number of unknown independent coefficients, in the case of a rectangular plate, when compared to the conventional Rayleigh-Ritz method. Closed form expressions for the linear and nonlinear fundamental frequency parameters for the all edges simply supported moderately thick rectangular plates are derived. The numerical results obtained from the present formulation are validated with those obtained from the existing literature for the given moderately thick plates.
Experimental and numerical investigation of force-frequency effect in crystal resonators
Authors: Mohammadi Mohammad Mostafa , Hamedi Mohsen
Published: September 2016

Piezoelectric resonators are widely applied in frequency control components in electronic devices, digital computers, and telecommunication. The stability of these resonators are affected by force-frequency and temperature-frequency effects. In this paper, a simple laboratory measurement method is introduced for measuring the force-frequency effect in piezoelectric resonators. The method employs the parallel resonance frequency of the resonator. It has been shown that the frequency shift of the parallel resonance frequency is very close to that of series resonance, and can be used instead for similar applications. Accordingly, the frequency shift of an AT-Cut quartz resonator which is subjected to a pair of opposed forces is measured. Also, the frequency shift is calculated by the finite element method. The numerical model and experimental results are in a good accordance. The obtained results can be used for better understanding of the force-frequency effect, its practical measurement to be used in simulation of crystal resonators and sensors behavior. Its industrial application will include design of down-hole sensors with better accuracy and robustness.
Investigation of self-excited vibrations in tread brake unit for railway vehicles
Authors: Mickoski Hristijan , Mickoski Ivan , Zdraveski Filip
Published: September 2016

The appearance of self-excited vibrations caused by dry friction of two elements or their contact surfaces is common practice in nature and technique. The braking force that slows down the railway vehicles is associated with dry sliding friction between the brake pads and the wheels. This leads to occurrence of self-excited vibrations in tread brake unit or simply brake block. This paper explores the phenomenon of self-excited vibrations in the brake block of railway vehicles. In order to demonstrate the existence of self-excited vibrations, mathematical model is created in Matlab Simulink and the results are compared with experimental data recorded during braking of electric powered train series 412-416 equipped with tread brake unit. Experimental studies have been performed in laboratory and in real-time conditions with braking train. This paper proves the occurrence of self-excited vibrations, their form and intensity.
Simulation of the motion of a four bar prosthetic knee mechanism fitted with a magneto-rheological damper
Authors: Attia E. M. , Abd El-Naeem M. A. , El-Gamal H. A. , Awad T. H. , Mohamed K. T.
Published: September 2016

A comprehensive study on the application of magneto-rheological (MR) damper in above knee prosthetic is introduced. The stance phase and the swing phase were studied. The knee model was composed of four-bar prosthetic knee mechanism with an MR damper. The equations of motion, of the model, were obtained using Newton's second law at the sagittal plane. To avoid the difficulties of the inverse dynamics, due to the damper’s nonlinear characteristics, a simplified approach was suggested for the Spencer model. This simplified approach was used to calculate the input voltage to the damper to obtain the desirable control force. The input data was obtained from the experimental work by sticking surface land marks to the artificial leg and filming it during performance of the daily activity. The Stream pix, AVI Edit, and WINanalyze software were used to calculate the global kinematics, for the required surface land marks, at each frame of the recorded motion. The model results represent the voltage required for the MR damper, during most daily activities, of a person who uses this kind of an artificial leg. The results showed that the required voltage depends on displacement, velocity and calculated force.
Impulse-based reciprocal measurement of the transfer functions of underwater structure
Authors: Cheng Guo , Cui Li-lin , Lv Zhi-qiang
Published: September 2016

An impulse-based reciprocal method is proposed for measuring the transfer functions of underwater structure. This method uses an impulse sound source, and the volume velocity of source is derived from the detected sound pressure. The influences of the reverberant sound field on the detected sound pressure are eliminated by an operation with time gates. Numerical simulation verifies that this impulses-based reciprocal measurement can obtain results with accuracy similar to the traditional reciprocal measurement method using electromagnetic source. Because much less time is required in the impulse-based measurement, the time efficiency is boosted. This method is also validated in a lake experiment, and the experimental result shows that the influences of the reverberant field on the derived volume velocity are eliminated.
Method for studying the structure of blast-induced vibrations in open-cast mines
Authors: Pyra Józef , Sołtys Anna
Published: September 2016

Detonations of explosive material charges are a source of intense paraseismic vibrations. These vibrations can cause damage to buildings and other infrastructure in the vicinity of the works, and can be a nuisance for their inhabitants. The article presents the problem of paraseismic vibration analysis, as induced by blasting works carried out in open-cast mines, using various methods of time – frequency, providing information about the duration of the signal, the frequency structure, and its energy.
Numerical analysis and optimization of wheel vibrations and radiation noises of the high-speed train
Authors: Lu Xue-yu , Lu Zheng-qiao , Lin Li-zong
Published: September 2016

Finite element and boundary element models of the standard wheel, damping wheels and S-type damping wheels were established and compared. The radial vibration and axial vibration of the standard wheel could be reduced to decrease the vibro-acoustic radiation. Regarding damping wheels and S-type damping wheels, the coupling between the radial vibration and axial vibrations of 1 pitch circle could be reduced to decrease the radiation noise. The vibration acceleration in the tread, rim and web plate was significantly improved after applying damping in the standard wheel. If the web plate was changed into S-type structure, the vibration acceleration of the wheel at three positions was further reduced. The radiation noise of S-type damping wheels was significantly improved. The radiation noise of the web plate was significantly greater than that of the tread, which was caused by the larger radiation area of the web plate.
Vibratory conveyor of the controlled transport velocity with the possibility of the reversal operations
Authors: Czubak Piotr
Published: September 2016

The new type of the reversible, vibratory conveyor in which a smooth velocity control (within the full range) in both directions is possible, is presented in the hereby paper. In order to investigate the correctness of the machine operation at first the physical model of the conveyor with a feed was constructed and then its mathematical model was developed. Simulations were performed for the eight-layer feed material in five columns. The obtained simulation results confirmed the proper operations of the conveyor.
Analysis of external flow characteristics in two-dimensional synthetic jets under excitation produced by cavity resonance
Authors: Lin Chi-Yu , Lin Chih-Lung , Yang Cheng-Fu
Published: September 2016

The paper studies the behaviors of synthetic jets under the excitation of cavity resonance which is produced by an isolated two-dimensional actuator. A cross hot-wire was used to obtain measurements within the velocity field. This research revealed a number of notable phenomena, such as the appearance of vortex pairs only in the vicinity of orifice exit as well as their rapid dissipation downstream. Our results of analysis of the plane velocities of the synthetic jets indicate that effective flow control can be achieved only in regions close to the orifice. It is interesting to note that a linear relationship could be obtained only by taking the logarithm of mean velocity (u-) as well as downstream distance (x) in different transverses, and by using a curve fitting then linear relations can be obtained. The slopes of synthetic jets under excitation of cavity resonance were between –7/10 and –3/5, which represents a sine wave of 160 Hz on 15 V. The original time-domain data was then converted using fast Fourier transform to the show power spectrum in order to reveal more about the flow behavior of synthetic jets. Characteristic frequencies were identified at 80 Hz and 160 Hz in the initial center of the orifice. The former frequency (80 Hz) can be attributed to the collision of the upper vortex and lower vortex of the synthetic jet. The latter frequency (160 Hz) refers to the excitation frequency of the signal source. Following the development of the synthetic jet, the excitation frequency of 160 Hz eventually disappeared downstream but the characteristic frequency of 80 Hz remained until x/H= 8. These experimental results make a valuable contribution to the further development of flow control in the future.
Mestrado profissional em Ensino de Matemática: identificação de seus produtos educacionais
Authors: Pilatti Luiz Alberto , Costa Jaqueline De Morais , Schirlo Ana Cristina , Rutz da Silva Sani De Carvalho , Maciel Pinheiro Nilcéia Aparecida , Frasson Antônio Carlos
Published: September 2016

O presente estudo tem como objetivo identificar os produtos educacionais desenvolvidos nos programas de pós-graduação stricto sensu, modalidade mestrado profissional, na área de Ensino, que tenham como foco principal ou como linha de pesquisa o Ensino de Matemática. Os produtos educacionais coletados foram os disponíveis nos sítios dos programas de mestrado profissional, no período entre 2004 e meados de 2014. Os itens foram analisados e categorizados. Verificou-se uma concentração de produtos educacionais nas categorias de propostas de atividades, manual e livro. Concluiu-se que, apesar da reconhecida relevância dos produtos desenvolvidos nos programas de mestrado profissional na área de Ensino de Matemática, há limitada diversidade nos produtos desenvolvidos, além de fragilidade nas estratégias de difusão dos mesmos.
Profissionais em Gestão da Pós-Graduação: perfil, competências e atividades na percepção dos secretários dos programas de pós-graduação em Educação
Authors: Da Silva Soares Silvia Adriana , Pauly Evaldo Luis
Published: September 2016

O artigo discute a atuação dos secretários de programas de pós-graduação em Educação, um tema relevante para a gestão da pesquisa no Brasil e ainda pouco estudado. A realização do VIII Fórum de Secretários(as) de Pós-Graduação em Educação da Região Sul permitiu a realização desta pesquisa. Como recurso metodológico, foi desenvolvido um questionário com questões fechadas sobre a identificação (gênero, idade, escolaridade), os conhecimentos necessários para o exercício da profissão, as atividades desenvolvidas e as condições de trabalho do respondente; a questão aberta versava sobre a satisfação dos secretários com sua função e com a instituição. Como resultado, constatou-se a complexidade da atuação dos secretários e a necessidade de qualificação desses profissionais para viabilizar o aperfeiçoamento do trabalho administrativo da pós-graduação em Educação.
Autoavaliação de médicos veterinários sobre sua competência clínica ao ingressarem em programas de residência
Authors: Marin van der Broocke Campos Gabriela
Published: September 2016

In the last decade, there was an upsurge in Veterinary Medicine undergraduate programs in Brazil. To control this expansion, it is important to evaluate the quality of teaching. This study had the goal of evaluating the clinical competence of veterinarians as they start their residency. Therefore, a self-evaluation questionnaire was applied to residents across all regions of the country. They were instructed to answer it according to the knowledge they had prior to residency. The questionnaire consisted of 90 questions, divided between clinical skills related to general procedures and practices in small and large animals. Each skill had to be classified as one of: not acquired, partially acquired or fully acquired. The average percentage of skills fully acquired was 57.4% for general procedures, 33.2% for clinical skills in small animals, 11.7% for large animals. The knowledge gap observed may be caused by insufficient training on clinical treatment. The results obtained in this study can be used as a guide for both undergraduate and residency programs, aiming to detect major areas for improvement to then apply corrective measures.
CHINA E EUA DESAFINAM EM FALA SOBRE SANÇÕES
Authors: Cavalcante Guilherme A G
Published: September 2016

Resenha
A RELAÇÃO DO SISTEMA CONSTITUTIVO E NORMATIVO DA UNIÃO EUROPÉIA versus A CONSTITUIÇÃO DOS ESTADOS EUROPEUS
Authors: Silva Adelson S
Published: September 2016

Ensaio
RESUMOS COMPLETOS DA PESQUISA: UM OLHAR DE VIAJANTE: JOSÉ DO PATROCÍNIO E O NORDESTE BRASILEIRO
Authors: Anunciação Victor
Published: September 2016

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PERCURSOS DE CLARICE
Authors: Gotlib - USP Nadia Battella
Published: September 2016

Artigo
A ORDEM PÚBLICA APLICADA À ADOÇÃO INTERNACIONAL
Authors: Cunha Luis Emmanuel Barbosa
Published: September 2016

Artigo
CONFLITO ENTRE O DIREITO INTERNO BRASILEIRO E O DIREITO INTERNACIONAL PÚBLICO: ANÁLISE SOB A PERSPECTIVA DA SOBERANIA
Authors: Pernambuco Mariana Azevedo
Published: September 2016

Ensaio
CRATOLOGIA E RELAÇÕES INTERNACIONAIS: BREVES NOTAS SOBRE OS FUNDAMENTOS E A CONTABILIDADE DO PODER NA POLÍTICA ENTRE AS NAÇÕES
Authors: Castro Thales
Published: September 2016

Artigo
ENSAIO SOBRE A CEGUEIRA
Authors: Rocha Andreza de Souza
Published: September 2016

Resenha
A LÍNGUA DE EULÁLIA: UM NOVO OLHAR DA NORMA NÃO PADRÃO
Authors: Codeceira Victor
Published: September 2016

Resenha
O GENOCÍDIO DE DARFUR E A SOCIEDADE DO ESPETÁCULO
Authors: Francisco Íris Viegas
Published: September 2016

Artigo
Blue-Light Transmittance of Esthetic Monolithic CAD/CAM Materials With Respect to Their Composition, Thickness, and Curing Conditions
Authors: Stawarczyk B , Awad D , Ilie N
Published: September 2016

Determining the amount of blue light (360-540nm) passing through nine monolithic computer-aided design/computer-aided manufacturing (CAD/CAM) materials depends on material thickness, initial irradiance, and the distance between the curing unit and the specimen's surface. A total of 180 specimens of two thicknesses (1 mm and 2 mm, n=10/subgroup) were fabricated from TelioCAD, VITA CAD-Temp (VCT), experimental nanocomposite, LAVA Ultimate (LU), VITA ENAMIC (VE), VITA MarkII (VM), IPS EmpressCAD (IEC), IPS e.maxCAD (IEM), and CELTRA DUO (CD). The irradiance passing through the CAD/CAM materials and thicknesses was measured using a light-emitting-diode curing unit with standard-power, high-power, and plasma modes by means of a USB4000 spectrometer. The curing unit was placed directly on the specimen's surface at 2- and 4-mm distances from the specimen's surface. Data were analyzed using a multivariate analysis and one-way analysis of variance with the post hoc Scheffé test (p<0.05). The highest transmitted irradiance was measured for VM and LU, followed by VCT and IEC, while the lowest values showed VE, followed by IEM and CD. The highest transmitted irradiance was recorded by exposing the material to the plasma mode, followed by the high- and standard-power modes. The measured irradiance was decreased by increasing the specimen's thickness from 1 to 2 mm. Fewer differences were measured when the curing unit was placed at 0 or 2 mm from the specimen's surface, and the irradiance passing through the specimens was lower at a distance of 4 mm.
Effect of Insufficient Light Exposure on Polymerization Kinetics of Conventional and Self-adhesive Dual-cure Resin Cements
Authors: Jang Y , Ferracane JL , Pfeifer CS , Park JW , Shin Y , Roh BD
Published: September 2016

Objectives: The purpose of this study was to investigate the influence of insufficient light exposure on the polymerization of conventional and self-adhesive dual-cure resin cements under ceramic restorations.

Methods: Two conventional dual-cure resin cements (Rely-X ARC, Duolink) and two self-adhesive resin cements (Rely-X U200, Maxcem Elite) were polymerized under different curing modes (dual-cure or self-cure), curing times (20 and 120 seconds), and thickness of a ceramic overlay (2 and 4 mm). Polymerization kinetics was measured by Fourier transform infrared spectroscopy for the initial 10 minutes and after 24 hours. Data were analyzed using mixed model analysis of variance (ANOVA), one-way ANOVA/Student-Newman-Keuls post hoc test, and paired t-test (α=0.05).

Results: When light-curing time was set to 20 seconds, the presence of the ceramic block significantly affected the degree of conversion (DC) of all resin cements. Especially, the DC of the groups with 20 seconds of light-curing time under 4 mm of ceramic thickness was even lower than that of the self-cured groups at 24 hours after polymerization (p<0.05). However, when light-curing time was set to 120 seconds, a similar DC compared with the group with direct light exposure (p>0.05) was achieved in all dual-cure groups except Maxcem Elite, at 24 hours after polymerization.

Conclusions: For both conventional and self-adhesive dual-cure resin cements, insufficient light exposure (20 seconds of light-curing time) through thick ceramic restoration (4 mm thick) resulted in a DC even lower than that of self-curing alone.
Earthquake in Nepal: A Miserable Environmental Hazard Visited by Nature
Authors: Dube Shiva Kant
Published: September 2016

Indian and Tibetan tectonic plates and therefore lies in a seismically active region. Historical data evidence the occurrence of destructive great earthquakes in the past. Earthquakes are caused mainly due to disequilibrium in any part of the crust of the earth. If we look at the world distribution of earthquake, it appears that the earthquake belts are closely associated with the weaker zones of the seismotectonics of the region. It is an instrument for seismic surveillance allowing a fast post-earthquake rescue operation. This paper incorporates a case of earthquake occurred in April, 2015 as one of the environmental hazards visited by nature which proved disastrous causing massive loss of lives and properties to the vulnerable regions. It can be taken as a lesson to mitigate massive loss of lives and properties selecting isostatically proper land structure and constructing safe settlements for habitat in Nepalese context.Academic Voices Vol.5 2015:  56-66
Impact of Conflict on Teaching Learning Process in Schools
Authors: Thapa Tara Bahadur
Published: September 2016

Conflict is abundantly present in every society. The nature and types of conflicts that emerge in school vary from school to school. The common types of conflicts usually occur between the students on one hand and school authority on the other. Other forms of conflicts include intrapersonal conflict among teachers as well as students regarding the causes of different norms and values, desires and selfishness. If conflicts are not resolved in time, they have destructive impacts in teaching learning, and it may lead to violence. This article highlights the causes of conflicts among students and teachers and its effects on teaching learning process in school.Academic Voices Vol.5 2015: 73-78
Professional Veterinary Programs' Perceptions and Experiences Pertaining to Emotional Support Animals and Service Animals, and Recommendations for Policy Development
Authors: Schoenfeld-Tacher Regina M. , Kogan Lori R.
Published: September 2016

Given the unique nature of programs in professional veterinary medicine (PVM), the increasing numbers of students requesting accommodations for emotional support animals (ESAs) in higher education settings is of growing interest to student affairs and administrative staff in PVM settings. Since the legislation pertaining to this type of support animal differs from the laws governing disability service animals, colleges and universities now need to develop new policies and guidelines. Representatives from a sample of 28 PVM programs completed a survey about the prevalence of student requests for ESAs and service animals. PVM associate deans for academic affairs also reported their perceptions of this issue and the challenges these requests might pose within veterinary teaching laboratories and patient treatment areas. Responses indicated that approximately one third of PVM programs have received requests for ESAs (32.1%) in the last 2 years, 17.9% have had requests for psychiatric service animals, and 17.9% for other types of service animals. Despite this, most associate deans reported not having or not being aware of university or college policies pertaining to these issues. Most associate deans are interested in learning more about this topic. This paper provides general recommendations for establishing university or PVM program policies.
Differences in Spending by Local Trail Users: Two-Part Model of Expenditures
Authors: Ermagun Alireza , Lindsey Greg
Published: September 2016

Urban multiuse trails are the backbones of nonmotorized transportation networks in metropolitan areas across the United States. These trails provide opportunities for recreation and utilitarian travel, increase access to important destinations, and serve other public purposes. A common rationale for trail development is that users spend money and support retail businesses in trail corridors. Expenditures by local trail users do not constitute new regional economic impacts but are important locally and of interest to planners and business owners who view trails as mechanisms to spur local economic activity. The results of intercept surveys completed by 1,282 trail users on the Central Ohio Greenway trail network in 2014 were used to estimate the probabilities and patterns that different types of trail users will make expenditures. Approximately one-fifth of trail users reported spending between $15.00 and $20.00 for food, drink, and other incidental items. Across all trail users the average expenditure by individuals was about $3.00 per visit. All else equal, cyclists were more than twice as likely as other users to report expenditures. Users visiting trails principally for recreation were 53% more likely to spend, while users visiting trails mainly for exercise were about 19% less likely. Longer trips to and on the trails were associated with higher spending. These results can be used to inform local planning, marketing, and economic development activities related to local trail networks.
Aging Populations and Transit-Oriented Development: Socioeconomic, Demographic, and Neighborhood Trends from 2000 and 2010
Authors: Wood Brittany S. , Horner Mark W. , Duncan Michael , Valdez-Torres Yazmin
Published: September 2016

In the coming years, transportation planners and policy makers in the United States will need to shift their focus to acknowledge the needs of the growing aging population. A principal task that must be addressed is how to cope with meeting the demands of aging adults who may not be able to operate and maintain their own personal vehicles because of growing physical and financial constraints. Transit-oriented developments (TODs), typically defined by mixed-use and pedestrian-friendly development surrounding a transit stop, are places that might benefit aging populations and meet their transportation needs. This paper explores demographic trends and characteristics surrounding transit-oriented developments. To compare how the environment has changed in terms of socioeconomic characteristics, this study examined census attributes such as people’s age, income by age, and the number of various activities performed in TODs. Also investigated were trends in TOD road infrastructure and activity locations. It was found that TODs and their adjacent areas in 2010 had a higher density of road network characteristics compared with TODs in 2000. It was also observed that aging populations (65 years and older) were a lower proportion of the population residing in TODs for 2000 and 2010. If TODs are a possible solution to meeting the accessibility needs of aging adults, more research is required to understand better how to attract aging populations to these communities.
Relationship Between Human Capital and Transportation Sustainability for the United States and Selected European Countries
Authors: Ahangari Hamed , Garrick Norman W. , Atkinson-Palombo Carol
Published: September 2016

There is a growing interest in developing reliable and meaningful composite indexes of transportation sustainability. Several such indexes have been developed, but none have been used for comparing countries. This paper introduces a cost-oriented national transportation sustainability index (NTSI) and uses it to compare the performance of the United States with 27 selected European countries for the years 2005 and 2011. A series of panel data models is then used to investigate the relationship between human capital, macroeconomic and social factors, and transportation sustainability. The results showed that Switzerland was the best performing country on the NTSI in 2005 but was displaced at the top by the United Kingdom in 2011. Other countries that performed quite well were the Nordic countries and some of the older member-nations of the European Union (EU). The United States was by far the worst performing country in terms of transportation sustainability in 2005 and 2011. One interesting finding was the split in the performance of the non–Nordic European Union countries. In general, the newer EU member nations had by far the best performance on the environmental subindex of the NTSI in 2005. But by 2011 this advantage had almost entirely eroded. The numbers suggest that this was caused by a rapid rate of increase in motorization in these countries that was not necessarily paralleled by corresponding changes in their economic performance. Overall, it was found that factors associated with a high level of human capital (such as high health index, high educational attainment, and low poverty level) were also associated with high levels of transportation sustainability. Conversely, high levels of motorization were associated with lower levels of transportation sustainability.
Cycling by Choice or Necessity?: Exploring the Gender Gap in Bicycling in Oregon
Authors: Singleton Patrick A. , Goddard Tara
Published: September 2016

In Oregon, as in other areas of the United States, a greater percentage of men than women bicycle. This study illuminates the gender gap in bicycling by exploring differences in bicycling between women and men in Oregon. A one-day statewide travel survey of more than 30,000 adults was examined. Comparisons between individual, household, and trip and activity characteristics for people grouped by gender (women versus men) and bicycling (made a bicycle trip or normally commuted by bicycle versus did not bicycle) were assessed using chi-square tests of independence. Many significant differences were found. In particular, women who lived alone, were not working, had no high school degree or driver’s license, and lived in low-income households or zero-vehicle households were less likely to bicycle than other women. Men with similar characteristics did not exhibit the same trends; sometimes they were even more likely to bicycle. These findings are consistent with a perspective that women who bicycle are more likely to bicycle by choice, whereas women of fewer means are less likely to turn to bicycling than are their male counterparts. In addition, there was partial support for the idea that women’s roles and responsibilities may contribute to this deficit (that is, for household maintenance and escorting but not necessarily for the presence of children). The study’s results begin to suggest a rethinking of bicycle-promoting policies and interventions to target certain women better, although further research is needed to understand bicycling’s gender gap more fully.
Environmental Justice and Pedestrianism: Sidewalk Continuity, Race, and Poverty in New Orleans, Louisiana
Authors: Lowe Kate
Published: September 2016

Extensive research documents the unequal distribution of benefits and harms from automobiles and transit, but little transportation research on environmental justice considers differing access to and quality of pedestrian infrastructure by race and income. This study uses an audit of sidewalk continuity adjacent to bus stops in New Orleans, Louisiana, to determine whether sidewalk continuity had a relationship to census tract-level poverty and racial composition. The analysis shows that minority populations and, to some extent, populations living in poverty are significantly associated with worse sidewalk connectivity. Disparities in the quality of pedestrian infrastructure warrant more attention, and future research could examine potential disparities in differing locations, as well as the role of governmental and nongovernmental actors in sidewalk provision.
Association between shunt-responsive idiopathic normal pressure hydrocephalus and alcohol
Authors: Hickman Thu-Trang , Shuman Matthew E. , Johnson Tatyana A. , Yang Felix , Rice Rebecca R. , Rice Isaac M. , Chung Esther H. , Wiemann Robert , Tinl Megan , Iracheta Christine , Chen Grace , Flynn Patricia , Mondello Mary Beth , Thompson Jillian , Meadows Mary-Ellen , Carroll Rona S. , Yang Hong Wei , Xing Hongyan , Pilgrim David , Chiocca E. Antonio , Dunn Ian F. , Golby Alexandra J. , Johnson Mark D.
Published: September 2016

OBJECTIVE

Idiopathic normal pressure hydrocephalus (iNPH) is characterized by ventriculomegaly, gait difficulty, incontinence, and dementia. The symptoms can be ameliorated by CSF drainage. The object of this study was to identify factors associated with shunt-responsive iNPH.

METHODS

The authors reviewed the medical records of 529 patients who underwent shunt placement for iNPH at their institution between July 2001 and March 2015. Variables associated with shunt-responsive iNPH were identified using bivariate and multivariate analyses. Detailed alcohol consumption information was obtained for 328 patients and was used to examine the relationship between alcohol and shunt-responsive iNPH. A computerized patient registry from 2 academic medical centers was queried to determine the prevalence of alcohol abuse among 1665 iNPH patients.

RESULTS

Bivariate analysis identified associations between shunt-responsive iNPH and gait difficulty (OR 4.59, 95% CI 2.32–9.09; p < 0.0001), dementia (OR 1.79, 95% CI 1.14–2.80; p = 0.01), incontinence (OR 1.77, 95% CI 1.13–2.76; p = 0.01), and alcohol use (OR 1.98, 95% CI 1.23–3.16; p = 0.03). Borderline significance was observed for hyperlipidemia (OR 1.56, 95% CI 0.99–2.45; p = 0.054), a family history of hyperlipidemia (OR 3.09, 95% CI 0.93–10.26, p = 0.054), and diabetes (OR 1.83, 95% CI 0.96–3.51; p = 0.064). Multivariate analysis identified associations with gait difficulty (OR 3.98, 95% CI 1.81–8.77; p = 0.0006) and alcohol (OR 1.94, 95% CI 1.10–3.39; p = 0.04). Increased alcohol intake correlated with greater improvement after CSF drainage. Alcohol abuse was 2.5 times more prevalent among iNPH patients than matched controls.

CONCLUSIONS

Alcohol consumption is associated with the development of shunt-responsive iNPH.