bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuning a PD Controller Based on an SVR for the Control of a Biped Robot Subject to External Forces and Slope Variation
Authors: Ferreira João P. , Crisóstomo Manuel , Coimbra A. Paulo 
Published: March 2014

Real-time balance control of an eight-link biped robot using a zero moment point (ZMP) dynamic model is difficult to achieve due to the processing time of the corresponding equations. To overcome this limitation an intelligent computing technique based on Support Vector Regression (SVR) is developed and presented in this paper. To implement a PD controller the SVR uses the ZMP error relative to a reference and its variation as inputs, and the output is the correction of the angle of the robot's torso, necessary for its sagittal balance. The SVR was trained based on simulation data generated using a PD controller. The initial values of the parameters of the PD controller were obtained by the second Ziegler-Nichols method. In order to evaluate the balance performance of the biped robot, three performance indexes are used. The ZMP is calculated by reading four force sensors placed under each of the robot's feet. The gait implemented in this biped is similar to a human gait, which is acquired and adapted to the robot's size. The main contribution of this paper is the fine-tuning of the ZMP controller based on the SVR. To implement and test this, the biped robot was subjected to external forces and slope variation. Some experiments are presented and the results show that the implemented gait combined with the correct tuning of the SVR controller is appropriate for use with this biped robot. The SVR controller runs at 0.2 ms, which is about 50 times faster than a corresponding first-order TSK neural-fuzzy network.
Multiple hydrological attractors under stochastic daily forcing: 2. Can multiple attractors emerge?
Authors: Peterson T. J. , Western A. W. , Argent R. M. 
Published: March 2014

AbstractThe companion paper showed that multiple steady state groundwater levels can exist within a hill‐slope Boussinesq‐vegetation model under daily stochastic forcing. Using a numerical limit‐cycle continuation algorithm, the steady states (henceforth attractors) and the threshold between them (henceforth repellor) were quantified at a range of saturated lateral conductivity values,
. This paper investigates if stochastic daily forcing can switch the catchment between both of the attractors. That is, an attractor may exist under average forcing conditions but can stochastic forcing switch the catchment into and out of each of the attractor basins?; i.e., making the attractor emerge. This was undertaken using the model of the companion paper and by completing daily time‐integration simulations at six values of the saturated lateral hydraulic conductivity,
; three having two attractors and three having only a deep water table attractor. By graphically analyzing the simulations, and comparing against simulations from a model modified to have only one attractor, multiple attractors were found to emerge under stochastic daily forcing. However, the emergence of attractors was significantly more subtle and complex than that suggested by the companion paper. That is, an attractor may exist but never emerge; both attractors may exist and both may emerge but identifying the switching between attractors was often ambiguous; and only one attractor may exist and but a second temporary attractor may exist and emerge during periods of high precipitation. This subtle and complex emergence of attractors was explained using continuation analysis of the climate forcing rate, and not a model parameter such as
. It showed that the temporary attractor existed over a large range of
values and this suggests that more catchments may have multiple attractors than suggested by the companion paper. By combining this continuation analysis with the time‐integration simulations, hydrological signatures indicative of a switch of multiple attractors were proposed. These signatures may provide a means for identifying actual catchments that have switched between multiple attractors.
Measurements and analysis of air quality in Islamabad, Pakistan
Authors: Rasheed Anjum , Aneja Viney P. , Aiyyer Anantha , Rafique Uzaira 
Published: March 2014

AbstractAmbient air quality of Islamabad, Pakistan, reveals that annual average mass concentration of particulate matter (PM2.5) (∼45 to ∼95 µg m−3) and nitric oxide (NO) (∼41 to ∼120 µg m−3) exceeds the Pakistan's National Environmental Quality Standards (NEQS). The annual ozone (O3) concentration is within the permissible limits; however, some of the hourly concentration exceeds the NEQS mostly during the summer months. Correlation studies suggest that carbon monoxide (CO) has a significant (p‐value ≤ 0.01) positive correlation with NO and NOy′; whereas, with O3, a significant (p‐value ≤ 0.01) negative correlation is observed. The regression analysis estimates the background CO concentration to be ∼300 to ∼600 ppbv in Islamabad. The higher ratio of CO/NO (∼10) suggests that mobile sources are the major contributor to NO concentration. On the other hand, the ratio analysis of sulfur dioxide (SO2)/NO for Islamabad (∼0.011) indicates that the point sources are contributing to SO2 in the city. NO and SO2 correlation indicates contribution of direct sulfur emission sources. Ratios of [CO] to [NO] and [SO2] to [NO], based on ambient air quality measurements, provide a test for emission inventories. The ratios of these pollutants in the available Islamabad emission inventories are consistent with ambient values for these pollutants. The correlation of PM2.5 and NO suggests that a fraction of secondary PM2.5 is produced by chemical conversion of NO into nitrates. The regional background O3 concentration for Islamabad has been determined to be ∼31 ppbv. This study suggests that there is an increase in O3 concentration with increases in photochemical conversion of NO to reservoir NOy′ species.
Lateral variations in the long‐term slip rate of the Chelungpu fault, Central Taiwan, from the analysis of deformed fluvial terraces
Authors: Simoes M. , Chen Y.‐G. , Shinde D. P. , Singhvi A. K. 
Published: March 2014

AbstractThe Chelungpu fault ruptured during the September 1999 Mw 7.6 Chi‐Chi earthquake, in Central Taiwan. This event was characterized by coseismic displacements increasing along strike and updip, from south to north. Previous studies suggested that such lateral variations also existed in the long‐term fault slip rate, but this has not yet been clearly documented. To address this, we investigate deformed fluvial terraces along the Choushui and Tatu‐Wu rivers, in the southern and central segments of the thrust fault. Optical ages of ~13 ka to ~38 ka obtained for these terraces enable estimation of fault slip rates of 5.8 ± 2.0 and 10.3 ± 1.6/−3.0 mm/yr for the southern and central segments, respectively. We combine these findings with the fault slip rate determined by other authors for the northern segment. Statistical analysis of the data suggests lateral variations in the long‐term fault slip rate, with values increasing toward the north. This pattern in the slip rate, averaged over approximately tens of thousand years, is similar to that observed for coseismic displacements during the Chi‐Chi earthquake. The similarities in the deformation pattern observed for one earthquake or cumulated over several events suggest that the Chi‐Chi earthquake could be characteristic of the earthquakes breaking the Chelungpu fault, with respect to slip distribution. Our results also allow for discussing the plausible evolution of major rivers draining the foothills of central Taiwan over the last ~40–60 kyr.
Remarkably consistent thermal state of the south central Chile subduction zone from 36°S to 45°S
Authors: Rotman Holly M. M. , Spinelli Glenn A. 
Published: March 2014

AbstractDelineating rupture areas of subduction zone earthquakes is necessary for understanding the controls on seismic and aseismic slip. For the largest recorded earthquake, the 1960 Chile event with moment magnitude 9.5, the rupture area is only loosely defined due to limitations in the global seismic network at the time. The rupture extends ~900 km along strike. Coastal deformation is consistent with either a constant rupture width of ~180–200 km along the entire length or a narrower (~115 km) rupture in the southern half. A southward narrowing of the seismogenic zone has been hypothesized to result from warming of the subduction zone to the south, where the subducting plate is younger. We present results of thermal models at 36°S, 38°S, 43°S, and 45°S to examine potential along‐strike changes in thermal state. Models most consistent with observed surface heat flux include fluid circulation in the oceanic crust that advects heat to the ocean. This ventilated hydrothermal circulation preferentially cools transects with young subducting lithosphere; frictional heating preferentially warms transects with older subducting lithosphere. The combined effects of frictional heating and hydrothermal circulation increase décollement temperatures in the 36°S and 38°S transects by up to ~155°C and decrease temperatures in the 45°S transect by up to ~150°C. In our preferred models, décollement temperatures 200 km landward of the trench in all four transects are ~350–400°C. This is consistent with a constant ~200 km wide seismogenic zone for the 1960 Mw 9.5 rupture, with decreasing slip magnitude in the southern half of the rupture.
Predictability of tracer dilution in large open channel flows: Analytical solution for the coefficient of variation of the depth‐averaged concentration
Authors: Pannone Marilena 
Published: March 2014

AbstractA large‐time analytical solution is proposed for the spatial variance and coefficient of variation of the depth‐averaged concentration due to instantaneous, cross sectionally uniform solute sources in pseudorectangular open channel flows. The mathematical approach is based on the use of the Green functions and on the Fourier decomposition of the depth‐averaged velocities, coupled with the method of the images. The variance spatial trend is characterized by a minimum at the center of the mass and two mobile, decaying symmetrical peaks which, at very large times, are located at the inflexion points of the average Gaussian distribution. The coefficient of variation, which provides an estimate of the expected percentage deviation of the depth‐averaged point concentrations about the section‐average, exhibits a minimum at the center which decays like t−1 and only depends on the river diffusive time scale. The defect of cross‐sectional mixing quickly increases with the distance from the center, and almost linearly at large times. Accurate numerical Lagrangian simulations were performed to validate the analytical results in preasymptotic and asymptotic conditions, referring to a particularly representative sample case for which cross‐sectional depth and velocity measurements were known from a field survey. In addition, in order to discuss the practical usefulness of computing large‐time concentration spatial moments in river flows, and resorting to directly measured input data, the order of magnitude of section‐averaged concentrations and corresponding coefficients of variation was estimated in field conditions and for hypothetical contamination scenarios, considering a unit normalized mass impulsively injected across the transverse section of 81 U.S. rivers.
Incorporation of epoxidized soybean oil as co‐matrix in epoxy resin toward developing plastisol/particulate toughened glass fiber composites
Authors: Rangasai Madoor Comandore , Bhosale Subhash Hanmant , Vinodkumar Singh Vismay , Ghosh Subrata Bandhu 
Published: March 2014

ABSTRACTEpoxidized soybean oil was incorporated as a co‐matrix into an epoxy resin, and the hybrid resin system was used for preparing glass fiber‐reinforced composites. Effect of addition of poly(vinyl chloride) plastisol and selected particulate fillers (fly ash and wood flour) to epoxy/epoxidized soybean oil matrix on mechanical and water uptake properties of glass fiber‐reinforced composites were studied. Fourier transform infrared spectroscopy was used to reveal the curing state of these composites. It was observed that tensile strengths and moduli decreased with the inclusion of all additives. However, addition of poly(vinyl chloride) plastisol, fly ash, and wood flour particulate fillers showed significant increase in impact strengths compared with neat epoxy composite in a synergistic manner. Water uptake results of the composites were found to be in good agreement with OH peak intensities obtained from Fourier transform infrared spectroscopy. Finally, acousto‐ultrasonic nondestructive technique was successfully used to assess damage states and to relate stress wave factors with tensile strength properties of modified epoxy‐based glass fiber composites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40586.
Preparation and characterization of a poly(methyl methacrylate) based composite bone cement containing poly(acrylate‐co‐silane) modified hydroxyapatite nanoparticles
Authors: Rao Minyu , Su Qiangwei , Liu Zhenzhen , Liang Peiqing , Wu Nan , Quan Changyun , Jiang Qing 
Published: March 2014

ABSTRACTThe purpose of this study was to study the mechanical properties of poly(methyl methacrylate) (PMMA)‐based bone cement incorporated with hydroxyapatite (HA) nanoparticles after surface modification by poly(methyl methacrylate‐co‐γ‐methacryloxypropyl timethoxysilane) [P(MMA‐co‐MPS)]. PMMA and P(MMA‐co‐MPS) were synthesized via free‐radical polymerization. P(MMA‐co‐MPS)‐modified hydroxyapatite (m‐HA) was prepared via a dehydration process between silane and HA; the bone cement was then prepared via the in situ free‐radical polymerization of methyl methacrylate in the presence of PMMA and P(MMA‐co‐MPS)–m‐HA. Fourier transform infrared (FTIR) spectroscopy, 1H‐NMR, and gel permeation chromatography were used to characterize the P(MMA‐co‐MPS). Thermogravimetric analysis and FTIR were used as quantitative analysis methods to measure the content of P(MMA‐co‐MPS) on the surface of HA. The effect of the proportion of m‐HA in the PMMA‐based bone cement on the mechanical properties was studied with a universal material testing machine. A 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay was also carried out to determine the cytotoxicity of the composite bone cement. The results showed that the surface modification of HA greatly improved the interaction between the inorganic and organic interfaces; this enhanced the mechanical properties of bone cement for potential clinical applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40587.
Review of ethanol dispersion, distribution, and elimination from the fetal compartment
Authors: Heller Michaela , Burd Larry 
Published: March 2014

BackgroundThis study is a review of alcohol dispersion into and elimination from the fetal compartment.MethodsPubMed searches were conducted for all years and all languages for relevant papers. We also hand searched the reference list of papers and text books for additional references.ResultsAlcohol concentration is determined by body water (49% for women), grams of ethanol consumed, and duration of drinking. The fetus has very limited metabolic capacity and transfer from the fetal compartment to maternal circulation is the major pathway to reduce fetal exposure. Vasoconstriction of the placenta‐umbilical unit from alcohol and smoking decreases rates of alcohol elimination from the fetal compartment. By 20 weeks of gestation, keratinization of fetal skin reduces the permeability of fetal skin to very low levels, increasing the duration of fetal exposure and complicating alcohol elimination from the fetal compartment. Two reabsorption pathways, the intramembranous pathway and fetal swallowing, create a recycling system where much of the ethanol the fetus excretes will be reabsorbed back into its circulatory system. Fetal re‐excretion of ethanol into the amniotic fluid occurs by means of fetal urine, breathing movements, and nasal excretions. Amniotic fluid then functions as a reservoir for ethanol, prolonging fetal exposure.ConclusionWhile the fetus has the ability to metabolize some ethanol, removal from the fetal–maternal unit relies primarily on maternal metabolic capacity. The alcohol elimination rate from the fetal compartment is approximately 3% to 4% of the maternal rate. We conclude with examples of the clinical relevance of information from this review. Birth Defects Research (Part A) 100:277–283, 2014. © 2014 Wiley Periodicals, Inc.
Cognitive comparison of unique and intermediate hues
Authors: Shamey Renzo , Sawatwarakul Weethima , Kuehni Rolf G. 
Published: March 2014

AbstractEight panels were prepared using the most highly chromatic Natural Colour System (NCS) samples for each hue. Each panel consisted of a test hue and two reference hues, the samples representing either mean unique hues (uH) R, Y, B, or G as determined in earlier experiments or intermediate hues half way between them, (iHs) Or, Pp, YG, and BG. Subjects were asked to determine whether they considered it possible to match the test hue with the reference hues. A total of 45 color‐normal subjects participated in the study in three separate trials with at least 24 h gap between consecutive trials. The results, with very few exceptions, showed that a match was considered possible for the four iHs based on a mixture of adjacent pairs of uHs, while the majority did not believe uHs could be matched based on amounts of adjacent iHs. Statistical analysis of the test results indicates that responses for the two sets of panels were significantly different (P ∼ 0, df = 539). The results provide support for Hering's uHs concept. However, a number of subjects believed that a mixture of adjacent iHs can result in a match of the reference uHs. Potential causes may include the use of experimental mean unique and intermediate hues and learned facts of colorant mixture. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 264–269, 2015
Development of web‐based science portal for large‐scale computing collaboration in earthquake engineering
Authors: Youn Choonhan , Lu Jinchi , Elgamal Ahmed , Baru Chaitan 
Published: March 2014

SUMMARYCyberinfrstructure has provided the wide‐ranging infrastructure needed to profit from the rapid progress in information technology, which has increased the demand for support from science and engineering applications. The science portals have played an important role in developing computing environments of such cyberinfrastructure. And discipline‐specific problem solving environments can be used productively, suitable for the study and development of scientific and technical applications. In this paper, we present a simple, web‐based computational portal framework for integrating numerical response from thousands of large‐scale earthquake engineering computational simulations. This system facilitates access and use of the high performance computing (HPC) resource by the researchers and provides an administratively and technologically streamlined environment for uploading input model files, creating the job script, editing the input model file, specifying HPC job parameters, querying running job status, and storing output data. Our web‐based science portal can be used to promote an efficient and effective simulation environment to help scientists as well as educators in their daily activities and speed up the scientific discovery process. The underlying numerical simulation platform is an open‐source object‐oriented framework for finite element analysis, Open System for Earthquake Engineering Simulation, funded by the Pacific Earthquake Engineering Research Center, and used by the proposed science portal to perform simulation applications in earthquake engineering. Copyright © 2014 John Wiley & Sons, Ltd.
The Pentynoate Ligand as a Building Block for Multimetallic Systems
Authors: Lin Yvonne H. , Duclaux Loraine , Gonzàlez de Rivera Ferran , Thompson Amber L. , Wilton‐Ely James D. E. T. 
Published: March 2014

AbstractThe complexes [RuRCl(CO)(BTD)(PPh3)2] (R = CH=CHtBu, CH=CHC6H4Me‐4, CH=CHC5H4FeC5H5; BTD = 2,1,3‐benzothiadiazole) and [Ru{C(C≡CPh)=CHPh}(CO)(PPh3)2] reacted with pentynoic acid to yield the same complex, [RuCl(O2CCH2CH2C≡CH)(CO)(PPh3)2], through cleavage of the vinyl ligand. In contrast, the products [RuR(O2CCH2CH2C≡CH)(CO)(PPh3)2] were formed when NaO2CCH2CH2C≡CH was used. An osmium example, [Os(CH=CHC6H4Me‐4)(O2CCH2CH2C≡CH)(CO)(PPh3)2], was also prepared from treatment of [Os(CH=CHC6H4Me‐4)Cl(CO)(BTD)(PPh3)2] with NaO2CCH2CH2C≡CH. Coupling of the pendant alkyne in [RuCl(O2CCH2CH2C≡CH)(CO)(PPh3)2] to yield the homodimetallic complex [{RuCl(O2CCH2CH2C≡C)(CO)(PPh3)2}2] was achieved by using [PdCl2(PPh3)2], CuI and NEt3. The reactivity of the alkyne unit was further exploited by the metallation of the alkyne with ClAu(PR3) (R = Ph, Cy) and Co2(CO)8 to yield the multimetallic species [Ru(CH=CHC6H4Me‐4)(O2CCH2CH2C≡CAuPR3)(CO)(PPh3)2] and [Ru(CH=CHC6H4Me‐4)(O2CCH2CH2CC{Co2(CO)6}H)(CO)(PPh3)2]. The structures of the complexes [Ru(CH=CHC6H4Me‐4)(O2CCH2CH2C≡CH)(CO)(PPh3)2] and [Ru(CH=CHtBu)(O2CCH2CH2C≡CH)(CO)(PPh3)2] were determined crystallographically.
p‐Cycle configuration possibilities over DRDA networks
Authors: Domżał Jerzy , Wójcik Robert , Jajszczyk Andrzej , Santiago del Río Pedro M. , Hernández José Alberto , Aracil Javier 
Published: March 2014

AbstractA resilience analysis of protection cycles (p‐cycle) configurations for Double Rings with Dual Attachment (DRDAs) architectures is presented in this work. DRDAs are composed of two rings with corresponding nodes connected by two separated links. There are several possible configurations of p‐cycles, which may be used in DRDAs for improving link or node protection upon link failure. The values of the parameters Mean Time To Failure and Mean Time To Disconnection are analysed in the paper to show the best choice of p‐cycles in DRDAs architectures. Copyright © 2014 John Wiley & Sons, Ltd.
Plasma dehydroepiandrosterone sulfate levels in patients with major depressive disorder correlate with remission during treatment with antidepressants
Authors: Morita Tokiko , Senzaki Koji , Ishihara Ryoko , Umeda Kazunori , Iwata Nakao , Nagai Taku , Hida Hirotake , Nabeshima Toshitaka , Yukawa Kazunori , Ozaki Norio , Noda Yukihiro 
Published: March 2014

ObjectiveWe attempted to investigate whether dehydroepiandrosterone sulfate (DHEA‐S) levels are associated with remission of major depressive disorder by assessing scores on the 17‐Item Structured Interview Guide for the Hamilton Depression before and after antidepressant treatment.MethodsPlasma DHEA‐S levels in 24 patients diagnosed with major depressive disorder on the basis of Diagnostic and Statistical Manual of Mental Disorders, fourth edition (text revision) before and after antidepressant treatment, and 24 healthy, gender‐matched, and age‐matched controls were measured using a radioimmunoassay kit.ResultsPlasma DHEA‐S levels in patients were significantly higher than those in healthy controls. In patients who achieved remission after antidepressant treatment, plasma DHEA‐S levels significantly declined compared with the levels before treatment. A significant correlation was observed between changes in DHEA‐S levels and Absence of Depressive and Anxious Mood scores, which are calculated from the 2‐Item Structured Interview Guide for the Hamilton Depression rating as follows: severity of depressive mood and anxiety in patients before and after antidepressant treatment.ConclusionsThese findings suggest that plasma DHEA‐S levels can be used as a putative indicator of the state of remission in patients with major depressive disorder. Copyright © 2014 John Wiley & Sons, Ltd.