bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of the Rotational Terms of the Dynamic Response Matrix
Authors: Montalvão D. , Ribeiro A.M.R. , Maia N.M.M. , Silva J.M.M.
Published: January 2014

The dynamic response of a structure can be described by both its translational and rotational receptances. The latter ones are frequently not considered because of the difficulties in applying a pure moment excitation or in measuring rotations. However, in general, this implies a reduction up to 75% of the complete model. On the other hand, if a modification includes a rotational inertia, the rotational receptances of the unmodified system are needed. In one method, more commonly found in the literature, a so called T‐block is attached to the structure. Then, a force, applied to an arm of the T‐block, generates a moment together with a force at the connection point. The T‐block also allows for angular displacement measurements. Nevertheless, the results are often not quite satisfactory. In this work, an alternative method based upon coupling techniques is developed, in which rotational receptances are estimated without the need of applying a moment excitation. This is accomplished by introducing a rotational inertia modification when rotating the T‐block. The force is then applied in its centroid. Several numerical and experimental examples are discussed so that the methodology can be clearly described. The advantages and limitations are identified within the practical application of the method.
Laterality of Facial Expressions of Emotion: Universal and Culture‐Specific Influences
Authors: Mandal Manas K. , Ambady Nalini
Published: January 2014

Recent research indicates that (a) the perception and expression of facial emotion are lateralized to a great extent in the right hemisphere, and, (b) whereas facial expressions of emotion embody universal signals, culture‐specific learning moderates the expression and interpretation of these emotions. In the present article, we review the literature on laterality and universality, and propose that, although some components of facial expressions of emotion are governed biologically, others are culturally influenced. We suggest that the left side of the face is more expressive of emotions, is more uninhibited, and displays culture‐specific emotional norms. The right side of face, on the other hand, is less susceptible to cultural display norms and exhibits more universal emotional signals.
Reliable Computation of Contact Force in FRP Composite Laminates under Transverse Impact
Authors: Mahanta B.B. , Reddy P. , Dutta Anjan , Chakraborty Debabrata
Published: January 2014

A simple and computationally efficient adaptive finite element analysis strategy has been adopted for accurate and reliable evaluation of contact force under transverse impact. Contact of a spherical and cylindrical impactor on FRP composite laminates are considered. Adaptive mesh refinement enables the finite element mesh to be obtained iteratively and automatically for the solution to have the desired level of accuracy. The refined meshes influence the calculated contact force and contact period appreciably. Influences of impactor velocity, mass of impactor, mass of the plate on discretization error as well as on contact force history have also been studied and are found to be sensitive.
Seeing without the Occipito‐Parietal Cortex: Simultagnosia as a Shrinkage of the Attentional Visual Field
Authors: Michel François , Henaff Marie-Anne
Published: January 2014

Following bi‐parietal lesions patient AT showed a severe inability to relocate her attention within a visual field which perimetry proved to be near‐normal. An experimental approach with tasks testing visuo‐spatial attention demonstrated a shrinkage of A.T.’s attentional visual field. With her visual attention narrowed to a kind of functional tunnel vision, the patient exhibited simultanagnosia (Wolpert, 1924), a symptom previously described in 1909 by Balint under the label of Psychic paralysis of “Gaze”. In striking contrast AT showed an efficient and effortless perception of complex natural scenes, which, according to recent work in normal subjects, necessitate few if any attentional resources.
Complex‐Damped Dynamic Systems in the Time and Frequency Domains
Authors: Bonisoli Elvio , Mottershead John E.
Published: January 2014

The fact that a complex‐damped model may represent the dynamic behaviour of elasto‐mechanical systems when acted upon by a magnetic field was brought to the attention of the structural dynamics community very recently by Professor Bruno A. D. Piombo and his colleagues at the Politecnico di Torino. In this paper a thorough analysis of the single degree‐of‐freedom complex‐damped mass‐spring system is presented. The analysis includes the root locus, the (non‐causal) impulse response, the frequency response and the transmissibility. Regions of different behaviour in the frequency response and transmissibility are described in detail. The stiffening behaviour observed in Prof. Piombo′s experiments and known as the "phantom effect" is demonstrated by the complex‐damped model.
Robustness of Command Input Preshaping Technique Applied to Residual Vibration Reduction
Authors: Pennacchi Paolo
Published: January 2014

Open‐loop control techniques, such as command input preshaping, are quite sensible to modelling errors and noise. In the paper, an analysis and a discussion about the robustness of the technique with respect to the errors than can affect estimation of the values of the system parameters is presented.
Transverse Vibration of Stiffened Plates with Cutouts Subjected to In‐Plane Uniform Edge Loading at the Plate Boundary
Authors: Srivastava A.K.L. , Datta P.K. , Sheikh A.H.
Published: January 2014

Vibration characteristics of stiffened plates with cutouts subjected to uni‐axial in‐plane uniform edge loading at the plate boundaries are investigated using the finite element method. The characteristic equations for the natural frequencies, buckling loads and their corresponding mode shapes are obtained from the equation of motion. The vibration frequencies and buckling load parameters for various modes of stiffened plates with cutouts have been determined for simply supported and clamped edge boundary conditions. In the structure modelling, the plate and the stiffeners are treated as separate elements where the compatibility between these two types of elements is maintained. Numerical results are presented for a range of hole to plate width ratios of 0 to 0.8. The correlations of the natural frequencies and buckling parameters obtained by the present approach with those available in the literature are found to show good agreement.
Experimental Analysis of Out‐of‐Plane Structural Vibrations of Two‐Wheeled Vehicles
Authors: Cossalter V. , Doria A. , Basso R. , Fabris D.
Published: January 2014

An analysis of the handling and stability of two‐wheeled vehicles depends on structural flexibility. This paper deals with laboratory experimentation carried out to identify the vehicle′s structural modes of vibration. The tests were carried out in stationary conditions considering several combinations of constraints.

Although the testing conditions did not correspond completely to actual road conditions, information about the influence of structural modes on weave and wobble modes was obtained. An analysis of the Frequency Response Functions obtained from several kinds of tests made it possible to establish the best testing conditions to obtain the desired information.

Experimental results regarding a super‐sport motorcycle and a maxi‐scooter are presented and discussed in this paper.
An Empirical Method for Particle Damping Design
Authors: Xu Zhi Wei , Chan K.W. , Liao W.H.
Published: January 2014

Particle damping is an effective vibration suppression method. The purpose of this paper is to develop an empirical method for particle damping design based on extensive experiments on three structural objects – steel beam, bond arm and bond head stand. The relationships among several key parameters of structure/particles are obtained. Then the procedures with the use of particle damping are proposed to provide guidelines for practical applications. It is believed that the results presented in this paper would be helpful to effectively implement the particle damping for various structural systems for the purpose of vibration suppression.
Shock Absorbing Characteristics and Vibration Transmissibility of Honeycomb Paperboard
Authors: Guo Yanfeng , Zhang Jinghui
Published: January 2014

Honeycomb paperboard is a kind of environmental‐friendly package cushioning material with honeycomb sandwich structure, and may be employed to protect products from shock or vibration damage during distribution. This paper deals with the characterization of properties of honeycomb paperboard relevant to its application for protective packaging in transportation, such as dynamic cushion curves and vibration transmissibility. The main feature of the paper is the evaluation on the shock absorbing characteristics and vibration transmissibility of honeycomb paperboards with different thickness by a series of experimental studies on the drop shock machine and vibration table. By using the fitting polynomial of the curve, the experiential formulas and characteristic coefficients of dynamic cushion curves of honeycomb paperboards with different thickness have been obtained. From the vibration tests with slow sine sweep, the peak frequencies and vibration transmissibility are measured and used to estimate the damping ratios. All the works provide basic data and curves relevant to its application for protective packaging in transportation.
Alternative Forms of the Rey Auditory Verbal Learning Test: A Review
Authors: Hawkins Keith A. , Dean David , Pearlson Godfrey D.
Published: January 2014

Practice effects in memory testing complicate the interpretation of score changes over repeated testings, particularly in clinical applications. Consequently, several alternative forms of the Auditory Verbal Learning Test (AVLT) have been developed. Studies of these typically indicate that the forms examined are equivalent. However, the implication that the forms in the literature are interchangeable must be tempered by several caveats. Few studies of equivalence have been undertaken; most are restricted to the comparison of single pairs of forms, and the pairings vary across studies. These limitations are exacerbated by the minimal overlapping across studies in variables reported, or in the analyses of equivalence undertaken. The data generated by these studies are nonetheless valuable, as significant practice effects result from serial use of the same form. The available data on alternative AVLT forms are summarized, and recommendations regarding form development and the determination of form equivalence are offered.
Health Monitoring of Thick Materials Using Piezoceramic Patches, Time Signals, and Wavelet Transmittance Functions
Authors: Hughes D.R. , Ghoshal A. , Rowe E. , Sundaresan M.J. , Schulz M.J. , Feaster J.T.
Published: January 2014

A relatively overlooked factor in both global and local methods of health monitoring is the nonlinear stiffness of structures caused by the cycling of cracks and delaminations. Global methods of health monitoring use modal parameters or frequency response functions in an inverse procedure to quantify damage in structures with thick sections. Global approaches use fewer sensors that detect only significantly large damage in structures due to damage caused by transient vibration. However, local methods use Lamb wave propagation to detect small damage within a structure by an array of closely spaced sensors and actuators. Local methods also become more difficult to use on thick or non‐homogeneous materials because wave propagation becomes complex. This paper develops a combined time series and wavelet analysis technique to improve damage detection in either thick, complex geometry, or non‐homogeneous materials. A wavelet transmittance function (WTF) is defined as the ratio of continuous wavelet transforms from the time responses at different locations on a structure. A new damage indicator was developed based upon wavelet transmittance function. The novelty of the method lies in the fact that a near real time inference about the damage and the approximate extent of damage can be drawn without historical data. A simulated model is illustrated to highlight the potential of the new damage indicator on a thick aluminum specimen. Then, experimental signal data from two sets of different experiments conducted on thick structures with a crack and a delamination were analyzed using the wavelet transmittance function to detect the presence and extent of the damages as reflected on the WTF maps. This paper mainly deals with the development of WTF and the associated damage indicator by analyzing the simulated and experimental sets of data.
Vibration Analysis of Rectangular Plates with Free Corners Using Spline‐Based Differential Quadrature
Authors: Zhong Hongzhi , Guo Qiang
Published: January 2014

A spline‐based differential quadrature method (SDQM) is elaborated and applied to the vibration analysis of rectangular plates with free edges. The sextic B‐spline functions are used to construct the pertaining cardinal spline interpolants. Thus, explicit expressions of weighting coefficients for approximation of derivatives are obtained. Free vibrations of rectangular plates with free edges, which pose considerable challenge to the conventional differential quadrature, are dealt with and the results are in excellent agreement with those in the literature, highlighting the effectiveness and potential of the spline‐based differential quadrature.
Test‐Retest Reliability of fMRI During Nonverbal Semantic Decisions in Moderate‐Severe Nonfluent Aphasia Patients
Authors: Kurland Jacquie , Naeser Margaret A. , Baker Errol H. , Doron Karl , Martin Paula I. , Seekins Heidi E. , Bogdan Andrew , Renshaw Perry , Yurgelun-Todd Deborah
Published: January 2014

Cortical reorganization in poststroke aphasia is not well understood. Few studies have investigated neural mechanisms underlying language recovery in severe aphasia patients, who are typically viewed as having a poor prognosis for language recovery. Although test‐retest reliability is routinely demonstrated during collection of language data in single‐subject aphasia research, this is rarely examined in fMRI studies investigating the underlying neural mechanisms in aphasia recovery.

The purpose of this study was to acquire fMRI test‐retest data examining semantic decisions both within and between two aphasia patients. Functional MRI was utilized to image individuals with chronic, moderate‐severe nonfluent aphasia during nonverbal, yes/no button‐box semantic judgments of iconic sentences presented in the Computer‐assisted Visual Communication (C‐ViC) program. We investigated the critical issue of intra‐subject reliability by exploring similarities and differences in regions of activation during participants′ performance of identical tasks twice on the same day. Each participant demonstrated high intra‐subject reliability, with response decrements typical of task familiarity. Differences between participants included greater left hemisphere perilesional activation in the individual with better response to C‐ViC training. This study provides fMRI reliability in chronic nonfluent aphasia, and adds to evidence supporting differences in individual cortical reorganization in aphasia recovery.
Review of the Development of Cap Models for Geomaterials
Authors: Sandler Ivan S.
Published: January 2014

The history of the development of Cap constitutive models is reviewed. The Cap family of models provides a powerful, yet adaptable way of representing many aspects of the dynamic stress‐strain behavior of geological materials. These models have been extensively used for more than three decades to characterize the highly nonlinear behavior of soils, rocks and concrete, and are particularly well suited to the dynamic analysis arising in ground shock and seismic applications. The modern series of Cap Models is based on the adaptation of several earlier models, and was introduced in the early 1970’s as a result of university and corporate R&D technology development sponsored by the United States government. Dr. Eugene Sevin played a role in these activities during his tenure at the Defense Nuclear Agency. In this paper, the basic behavior of the early models is briefly discussed and compared, and the reasons for the introduction of Cap Models are outlined. Many adaptations of the Cap Model have been developed since the first model was introduced, and the salient features of some of these model extensions are also reviewed.
Wheel‐Running Modestly Promotes Functional Recovery after a Unilateral Cortical Lesion in Rats
Authors: Zhao Xiurong , Aronowski Jaroslaw , Liu Shi-Jie , Schallert Timothy , Zhang Jie , Strong Roger , Ou Zhi-Shuo , Nguyen Theresa , Grotta James C.
Published: January 2014

Background: We aimed to determine whether early or delayed wheel‐running (W) after a cortical lesion in rats influences functional recovery and protein expression involving synaptic plasticity.

Methods: 57 rats were arranged in 4 groups: (1) Sham, (2) NMDA, (3) W‐24 h or (4) W‐72 h (W‐24 h and W‐72 h means wheel‐running for 14 days starting day 1 or day 3 after NMDA lesion). NMDA produced a standardized lesion in the unilateral sensorimotor cortex and detectable behavioral deficits. Synaptogenesis was measured by immunohistochemistry.

Results: Wheel‐running starting after 24 h had no detectable effect, but it significantly speeded functional recovery when delayed to after 72 h. These results were in accordance with a marker linked to synaptogenesis.

Conclusion: Wheel‐running starting 3 days, but not 1 day, after an NMDA lesion is associated with improved functional recovery.
Vibration Analysis of Rectangular Plates with One or More Guided Edges via Bicubic B‐Spline Method
Authors: Si W.J. , Lam K.Y. , Gong S.W.
Published: January 2014

A simple and accurate method is proposed for the vibration analysis of rectangular plates with one or more guided edges, in which bicubic B‐spline interpolation in combination with a new type of basis cubic B‐spline functions is used to approximate the plate deflection. This type of basis cubic B‐spline functions can satisfy simply supported, clamped, free, and guided edge conditions with easy numerical manipulation. The frequency characteristic equation is formulated based on classical thin plate theory by performing Hamilton′s principle. The present solutions are verified with the analytical ones. Fast convergence, high accuracy and computational efficiency have been demonstrated from the comparisons. Frequency parameters for 13 cases of rectangular plates with at least one guided edge, which are possible by approximate or numerical methods only, are presented. These results are new in literature.
Acceleration Feedback‐Based Active and Semi‐Active Seismic Response Control of Rail‐Counterweight Systems of Elevators
Authors: Rildova  , Singh M.P.
Published: January 2014

Based on the observations in the past earthquake events, the traction elevators in buildings are known to be vulnerable to earthquake induced ground motions. Among several components of an elevator, the counterweight being heaviest is also known to be more susceptible than others. The inertial effects of the counterweight can overstress the guide rails on which it moves. Here we investigate to use the well‐known acceleration feedback‐based active and semi‐active control methods to reduce stresses in the rails. The only way a control action can be applied to a moving counterweight‐rail system is through a mass damper placed in the plane of the counterweight. For this, a part of the counterweight mass can be configured as a mass damper attached to a small actuator for an active scheme or to a magneto‐rheological damper for a semi‐active scheme. A comprehensive numerical study is conducted to evaluate the effectiveness of the proposed configuration of control system. It is observed that the two control schemes are effective in reducing the stress response by about 20 to 25% and improve the system fragility over a good range of seismic intensities.
Improving Robustness of Tuned Vibration Absorbers Using Shape Memory Alloys
Authors: Elahinia Mohammad H. , Koo Jeong-Hoi , Tan Honghao
Published: January 2014

A conventional passive tuned vibration absorber (TVA) is effective when it is precisely tuned to the frequency of a vibration mode; otherwise, it may amplify the vibrations of the primary system. In many applications, the frequency often changes over time. For example, adding or subtracting external mass on the existing primary system results in changes in the system’s natural frequency. The frequency changes of the primary system can significantly degrade the performance of TVA. To cope with this problem, many alternative TVAs (such as semiactive, adaptive, and active TVAs) have been studied. As another alternative, this paper investigates the use of Shape Memory Alloys (SMAs) in passive TVAs in order to improve the robustness of the TVAs subject to mass change in the primary system. The proposed SMA‐TVA employs SMA wires, which exhibit variable stiffness, as the spring element of the TVA. This allows us to tune effective stiffness of the TVA to adapt to the changes in the primary system′s natural frequency. The simulation model, presented in this paper, contains the dynamics of the TVA along with the SMA wire model that includes phase transformation, heat transfer, and the constitutive relations. Additionally, a PID controller is included for regulating the applied voltage to the SMA wires in order to maintain the desired stiffness. The robustness analysis is then performed on both the SMA‐TVA and the equivalent passive TVA. For our robustness analysis, the mass of the primary system is varied by ± 30% of its nominal mass. The simulation results show that the SMA‐TVA is more robust than the equivalent passive TVA in reducing peak vibrations in the primary system subject to change of its mass.
From Transmission Error Measurements to Angular Sampling in Rotating Machines with Discrete Geometry
Authors: Remond Didier , Mahfoudh Jarir
Published: January 2014

The benefits of angular sampling when measuring various signals in rotating machines are presented and discussed herein. The results are extracted from studies on transmission error measurements with optical encoders in the field of power transmissions and can be broadened to include phase difference measurements, such as torsional vibrations, and applied to control, monitoring and measurement in rotating machines with discrete geometry. The main conclusions are primarily that the use of angular sampling enables the exact location of harmonics and, consequently, the obtaining of spectral amplitude components with precision. This is always true even if the resolution of encoders is not directly related to the studied discrete geometry. It then becomes possible to compare these harmonics under different operating conditions, especially when speed varies, without changing any parameters in spectral analysis (window length, spectral resolution, etc.). Moreover, classical techniques of improving signal to noise ratio by averaging become fully efficient in the detection of defective elements. This study has been made possible thanks to the technique of transmission error measurement with optical encoders that allows the comparison of sampling procedures, based on the same raw data.

The intensive use of such transducers and the development of an original transmission error measurement technique lead to advocate the use of angular sampling in experimental measurements in rotating machines with discrete geometry.
Integrated Structural Health Assessment Using Piezoelectric Active Sensors
Authors: Wait Jeannette R. , Park Gyuhae , Farrar Charles R.
Published: January 2014

This paper illustrates an integrated approach for identifying structural damage. The method presented utilizes piezoelectric (PZT) materials to actuate/sense the dynamic response of the structures. Two damage identification techniques are integrated in this study, including impedance methods and Lamb wave propagations. The impedance method monitors the variations in structural mechanical impedance, which is coupled with the electrical impedance of the PZT patch. In Lamb wave propagations, one PZT patch acting as an actuator launches an elastic wave through the structure, and responses are measured by an array of PZT sensors. The changes in both wave attenuation and reflection are used to detect and locate the damage. Both the Lamb wave and impedance methods operate in high frequency ranges at which there are measurable changes in structural responses even for incipient damage such as small cracks, debonding, or loose connections. The combination of the local impedance method with the wave propagation based approach allows a better characterization of the system’s structural integrity. The paper concludes with experimental results to demonstrate the feasibility of this integrated active sensing technology.
Reliable Shape Optimization of Structures Subjected to Transient Dynamic Loading Using Genetic Algorithms
Authors: Chand Sabyasachi , Dutta Anjan
Published: January 2014

This paper presents a reliable method of solution of two dimensional shape optimization problems subjected to transient dynamic loads using Genetic Algorithms. Boundary curves undergoing shape changes have been represented by B‐splines. Automatic mesh generation and adaptive finite element analysis modules are integrated with Genetic algorithm code to carry out the shape optimization. Both space and time discretization errors are evaluated and appropriate finite element mesh and time step values as obtained iteratively are adopted for accurate dynamic response. Two demonstration problems have been solved, which show convergence to the optimal solution with number of generations. The boundary curve undergoing shape optimization shows smooth shape changes. The combinations of automatic mesh generator with proper boundary definition capabilities, analysis tool with error estimation and Genetic algorithm as optimization engine have been observed to behave as a satisfactory shape optimization environment to deal with real engineering problems.
Acquired Dyslexia and Dysgraphia in Chinese
Authors: Yin Wengang , He Shengxi , Weekes Brendan Stuart
Published: January 2014

Understanding how the mappings between orthography and phonology in alphabetic languages are learned, represented and processed has been enhanced by the cognitive neuropsychological investigation of patients with acquired reading and writing disorders. During the past decade, this methodology has been extended to understanding reading and writing in Chinese leading to new insights about language processing, dyslexia and dysgraphia. The aim of this paper is to review reports of patients who have acquired dyslexia and acquired dysgraphia in Chinese and describe the functional architecture of the reading and writing system. Our conclusion is that the unique features of Chinese script will determine the symptoms of acquired dyslexia and dysgraphia in Chinese.
Qualitative Evaluation of Divergent Thinking in Patients with Schizophrenia
Authors: Nemoto Takahiro , Mizuno Masafumi , Kashima Haruo
Published: January 2014

Patients with schizophrenia show deficits across a broad spectrum of neurocognitive domains. In particular, deficits in verbal fluency are common. Verbal fluency tests are neuropsychological tests that assess frontal lobe function or executive function but also assess divergent thinking. However, few studies have considered the impairment of verbal fluency from the viewpoint of divergent thinking. To consider the structure of divergent thinking, not only verbal assessments but also non‐verbal assessments are indispensable. We administered several fluency tests, the idea fluency test, the design fluency test, and word (letter and category) fluency tests to 26 patients with schizophrenia and 26 healthy control subjects to evaluate divergent thinking in both groups and assessed their responses qualitatively. An acceptable minimal level of intelligence was maintained in the patient group. Although attention and executive functioning were relatively preserved in the subjects with schizophrenia, they demonstrated significant deficits in divergent thinking and had particular difficulty in producing ideas and designs requiring concept flexibility, a conversion of viewpoint, originality, or novelty. Research on deficits in divergent thinking in patients with schizophrenia may contribute to the development of cognitive and behavioral rehabilitation programs.
A Method of Symmetrization of Asymmetric Dynamical Systems
Authors: Liu C.Q.
Published: January 2014

This paper presents an approach to transform asymmetric systems into symmetric systems by equivalence transformation and discusses what forms of restrictions should be imposed on the system matrices so that they can be simultaneously transformed into symmetric matrices. Conditions of symmetrizability obtained here are more “liberal” and numerical calculations of this transformation are more straightforward. Several examples are provided to illustrate the new approach.
Simulation of the Collapse of an Underwater Explosion Bubble under a Circular Plate
Authors: Kan Kit-Keung , Stuhmiller James H. , Chan Philemon C.
Published: January 2014

A two‐fluid, computational fluid dynamics study of the phenomena of bubble collapse under a submersed flat plate has been performed. In order to handle the rapidly changing bubble‐water interface accurately, second order upwind differencing is used in calculating the advection term. Good agreement with experimental data is obtained for the pressure distribution on the plate. The computational results provide insight into the phenomenology of the jet impact, the formation of a radial hydraulic jump, and the complex interaction of that hydraulic jump with the collapsing toroidal bubble.
Letter‐By‐Letter Reading: Natural Recovery and Response to Treatment
Authors: Beeson Pélagie M. , Magloire Joël G. , Robey Randall R.
Published: January 2014

The present investigation provides a longitudinal study of an individual (RB) with acquired alexia following left posterior cerebral artery stroke. At initial testing, RB exhibited acquired alexia characterized by letter‐by‐letter (LBL) reading, mild anomic aphasia, and acquired agraphia. Repeated measures of reading accuracy and rate were collected for single words and text over the course of one year, along with probes of naming and spelling abilities. Improvements associated with natural recovery (i.e., without treatment) were documented up to the fourth month post onset, when text reading appeared to be relatively stable. Multiple oral reading (MOR) treatment was initiated at 22 weeks post‐stroke, and additional improvements in reading rate and accuracy for text were documented that were greater than those expected on the basis of spontaneous recovery alone. Over the course of one year, reading reaction times for single words improved, and the word‐length effect that is the hallmark of LBL reading diminished. RB′s response to treatment supports the therapeutic value of MOR treatment to in LBL readers. His residual impairment of reading and spelling one‐year post stroke raised the question as to whether further progress was impeded by degraded orthographic knowledge.
Frequency Effects with Visual Words and Syllables in a Dyslexic Reader
Authors: Stenneken Prisca , Conrad Markus , Hutzler Florian , Braun Mario , Jacobs Arthur M.
Published: January 2014

The present study investigated the nature of the inhibitory syllable frequency effect, recently reported for normal readers, in a German‐speaking dyslexic patient. The reading impairment was characterized as a severe deficit in naming single letters or words in the presence of spared lexical processing of visual word forms. Three visual lexical decision experiments were conducted with the dyslexic patient, an unimpaired control person matched to the patient and a control group: Experiment 1 manipulated the frequency of words and word‐initial syllables and demonstrated systematic effects of both factors in normal readers and in the dyslexic patient. The syllable frequency effect was replicated in a second experiment with a more strictly controlled stimulus set. Experiment 3 confirmed the patient’s deficit in activating phonological forms from written words by demonstrating that a pseudohomophone effect as observed in the unimpaired control participants was absent in the dyslexic patient.
Optimization of the G&H Bubble Model
Authors: Geers Thomas L. , Park Chung-Kyu
Published: January 2014

A spherical model for the bubble created by an underwater explosion is enhanced to account, in approximate fashion, for the effect of bubble distortion on translation and dilation. The enhancement consists of introducing artificial drag in the form C|v|P
, where ν is translation velocity, and C, P produce an optimum fit to empirical formulas for the second dilation maximum and first two translation jumps. The recommended values are C = 0.4 and P = 1 for charge weights between 100 lb–1000 lb and and depths exceeding 200 ft.
Augmentation of DAA Staggered – Solution Equations in Underwater Shock Problems for Singular Structural Mass Matrices
Authors: DeRuntz John A.
Published: January 2014

The numerical solution of underwater shock fluid – structure interaction problems using boundary element/finite element techniques became tractable through the development of the family of Doubly Asymptotic Approximations (DAA). Practical implementation of the method has relied on the so‐called augmentation of the DAA equations. The fluid and structural systems are respectively coupled by the structural acceleration vector in the surface normal direction on the right hand side of the DAA equations, and the total pressure applied to the structural equations on its right hand side. By formally solving for the acceleration vector from the structural system and substituting it into its place in the DAA equations, the augmentation introduces a term involving the inverse of the structural mass matrix. However there exist at least two important classes of problems in which the structural mass matrix is singular. This paper develops a method to carry out the augmentation for such problems using a generalized inverse technique.
Bi‐Hemispheric Engagement in the Retrieval of Autobiographical Episodes
Authors: Vandekerckhove Marie M. P. , Markowitsch Hans J. , Mertens Markus , Woermann Friedrich G.
Published: January 2014

Functional magnetic resonance imaging (fMRI) was used to study the neural correlates of neutral, stressful, negative and positive autobiographical memories. The brain activity produced by these different kinds of episodic memory did not differ significantly, but a common pattern of activation for different kinds of autobiographical memory was revealed that included (1) largely bilateral portions of the medial and superior temporal lobes, hippocampus and parahippocampus, (2) portions of the ventral, medial, superior and dorsolateral prefrontal cortex, (3) the anterior and posterior cingulate, including the retrosplenial, cortex, (4) the parietal cortex, and (5) portions of the cerebellum. The brain regions that were mainly activated constituted an interactive network of temporal and prefrontal areas associated with structures of the extended limbic system. The main bilateral activations with left‐sided preponderance probably reflected reactivation of complex semantic and episodic self‐related information representations that included previously experienced contexts. In conclusion, the earlier view of a strict left versus right prefrontal laterality in the retrieval of semantic as opposed to episodic autobiographical memory, may have to be modified by considering contextual variables such as task demands and subject variables. Consequently, autobiographical memory integration should be viewed as based on distributed bi‐hemispheric neural networks supporting multi‐modal, emotionally coloured components of personal episodes.
Persisting Reversed Clock Syndrome
Authors: Orssaud Christophe , Halimi Philippe , Jeunne Claire Le , Dufier Jean Louis
Published: January 2014

Background: The reversed clock phenomenon results in the transposition of objects from one side to another. Its major manifestation consists in the reversal of clock numbers in clock‐drawing test. It could be due to a stroke disrupting attentional cerebral network. This phenomenon usually regresses in a few days.

Objective: To report a case of reversed clock phenomenon with disorders of space representation that did not regress spontaneously.

Design: Case report. Patient: A 67 year‐old woman was referred due to headaches associated with gait disorder, visual field deficit and disturbance of space representation.

Results: Magnetic resonance imaging demonstrates two right cerebral infarcts mainly localized in the parieto‐occipital region. A week after her stoke, clinical testing confirms a reversed clock phenomenon. The patient placed the hands of a clock in the opposite direction of what was specified. She got lost at home locating rooms in directions opposite to their real ones. Rehabilitation sessions partially improved these manifestations.

Conclusion: Although it usually improves in a few days, reversed clock phenomenon can persist longer. Rehabilitation sessions based on localization exercises may be helpful in such situations.
Neuroleptic Malignant Syndrome: Diagnostic and Therapeutic Dilemmas
Authors: Fekadu Abebaw , Bisson Jonathan I.
Published: January 2014

Neuroleptic malignant syndrome (NMS) is a life threatening medical state complicating the use of antipsychotic medications and other drugs that affect the dopaminergic system on administration or withdrawal. The condition was recognised nearly half a century ago, shortly after the discovery of antipsychotic medications. However, there are still no systematic studies about NMS. There are no definitive guidelines on its treatment. Although early recognition is emphasised and usually possible, delayed diagnosis is not rare. We here report on a case of NMS complicated by renal failure, and possibly respiratory failure. The report underscores the seriousness of delayed diagnosis and puts forward a comprehensive management recommendation based on our experience and the existing literature.
Acquired Surface Alexia in Spanish: A Case Report
Authors: Ferreres Aldo R. , Cuitiño Macarena Martinez , Olmedo Alicia
Published: January 2014

This paper reports a case study of acquired surface alexia in Spanish and discusses the most suitable tests to detect this syndrome in a writing system that is very regular for reading at the segmental and supra‐segmental levels. Patient MM has surface alexia characterized by quantitatively good performance in reading words and pseudowords; accurate but slow and syllabic reading of words, nonwords and sentences; good performance in lexical decision tasks including words and nonwords; errors in lexical decision with pseudohomophones; and homophone confusions. This pattern of reading can be interpreted as a disorder in the lexical reading route and overdependence on the non‐lexical route. We discuss nonlexical impairments and the interpretation of alexia and suggest tasks to identify surface alexia in a shallow orthography.
The Thermoelastic Dynamic Response of Thick Closed Laminated Shell
Authors: Ding Ke Wei
Published: January 2014

Giving up any assumptions about displacement models and stress distribution, weak formulation of mixed state equations including boundary conditions of laminated cylindrical shell are presented. Thermal stresses mixed Hamilton equation of closed cylindrical shell is established. The analytical solutions are obtained for the thermoelastic dynamic response of a thick closed laminated shell subjected to temperature variation. Every equation of elasticity can be satisfied, and all elastic constants can be taken into account. Arbitrary precision of a desired order can be obtained.
Use of Response Surface Metamodels for Identification of Stiffness and Damping Coefficients in a Simple Dynamic System
Authors: Rutherford A.C. , Inman D.J. , Park G. , Hemez F.M.
Published: January 2014

Metamodels have been used with success in many areas of engineering for decades but only recently in the field of structural dynamics. A metamodel is a fast running surrogate that is typically used to aid an analyst or test engineer in the fast and efficient exploration of the design space. Response surface metamodels are used in this work to perform parameter identification of a simple five degree of freedom system, motivated by their low training requirements and ease of use. In structural dynamics applications, response surface metamodels have been utilized in a forward sense, for activities such as sensitivity analysis or uncertainty quantification. In this study a polynomial response surface model is developed, relating system parameters to measurable output features. Once this relationship is established, the response surface is used in an inverse sense to identify system parameters from measured output features.

A design of experiments is utilized to choose points, representing a fraction of the full design space of interest, for fitting the response surface metamodel. Two parameters commonly used to characterize damage in a structural system, stiffness and damping, are identified. First changes are identified and located with success in a linear 5DOF system. Then parameter identification is attempted with a nonlinear 5DOF system and limited success is achieved. This work will demonstrate that use of response surface metamodels in an inverse sense shows promise for use in system parameter identification for both linear and weakly nonlinear systems and that the method has potential for use in damage identification applications.
Axial Vibration Confinement in Nonhomogenous Rods
Authors: Choura S. , EL-Borgi S. , Nayfeh A.H.
Published: January 2014

A design methodology for the vibration confinement of axial vibrations in nonhomogenous rods is proposed. This is achieved by a proper selection of a set of spatially dependent functions characterizing the rod material and geometric properties. Conditions for selecting such properties are established by constructing positive Lyapunov functions whose derivative with respect to the space variable is negative. It is shown that varying the shape of the rod alone is sufficient to confine the vibratory motion. In such a case, the vibration confinement requires that the eigenfunctions be exponentially decaying functions of space, where the notion of spatial domain stability is introduced as a concept dual to that of the time domain stability. It is also shown that vibration confinement can be produced if the rod density and/or stiffness are varied with respect to the space variable while the cross‐section area is kept constant. Several case studies, supporting the developed conditions imposed on the spatially dependent functions for vibration confinement in vibrating rods, are discussed. Because variation in the geometric and material properties might decrease the critical buckling loads, we also discuss the buckling problem.
A State Space Method for Modal Identification of Mechanical Systems from Time Domain Responses
Authors: Liu Xiaobo
Published: January 2014

A new state space method is presented for modal identification of a mechanical system from its time domain impulse or initial condition responses. A key step in this method is the identification of the characteristic polynomial coefficients of an adjoint system. Once these coefficients are determined, a canonical state space realization of the adjoint system and the system′s modal parameters are formulated straightforwardly. This method is conceptually and mathematically simple and is easy to be implemented. Detailed mathematical treatments are demonstrated and numerical examples are provided to illustrate the use and effectiveness of the method.
Deep Dysgraphia in Turkish
Authors: Raman Ilhan , Weekes Brendan Stuart
Published: January 2014

Deep dysgraphic patients make semantic errors when writing to dictation and they cannot write nonwords. Extant reports of deep dysgraphia come from languages with relatively opaque orthographies. Turkish is a transparent orthography because the bidirectional mappings between phonology and orthography are completely predictable. We report BRB, a biscriptal Turkish‐English speaker who has acquired dysgraphia characterised by semantic errors as well as effects of grammatical class and imageability on writing in Turkish. Nonword spelling is abolished. A similar pattern of errors is observed in English. BRB is the first report of acquired dysgraphia in a truly transparent writing system. We argue that deep dysgraphia results from damage to the mappings that are common to both languages between word meanings and orthographic representations.
A Model Predictive Algorithm for Active Control of Nonlinear Noise Processes
Authors: Zhang Qi-Zhi , Gan Woon-Seng , Zhou Ya-li
Published: January 2014

In this paper, an improved nonlinear Active Noise Control (ANC) system is achieved by introducing an appropriate secondary source. For ANC system to be successfully implemented, the nonlinearity of the primary path and time delay of the secondary path must be overcome. A nonlinear Model Predictive Control (MPC) strategy is introduced to deal with the time delay in the secondary path and the nonlinearity in the primary path of the ANC system. An overall online modeling technique is utilized for online secondary path and primary path estimation. The secondary path is estimated using an adaptive FIR filter, and the primary path is estimated using a Neural Network (NN). The two models are connected in parallel with the two paths. In this system, the mutual disturbances between the operation of the nonlinear ANC controller and modeling of the secondary can be greatly reduced. The coefficients of the adaptive FIR filter and weight vector of NN are adjusted online. Computer simulations are carried out to compare the proposed nonlinear MPC method with the nonlinear Filter‐x Least Mean Square (FXLMS) algorithm. The results showed that the convergence speed of the proposed nonlinear MPC algorithm is faster than that of nonlinear FXLMS algorithm. For testing the robust performance of the proposed nonlinear ANC system, the sudden changes in the secondary path and primary path of the ANC system are considered. Results indicated that the proposed nonlinear ANC system can rapidly track the sudden changes in the acoustic paths of the nonlinear ANC system, and ensure the adaptive algorithm stable when the nonlinear ANC system is time variable.
Pre‐Acting Control for Shock and Impact Isolation Systems
Authors: Balandin D.V. , Bolotnik N.N. , Pilkey W.D.
Published: January 2014

Pre‐acting control in shock/impact isolation systems is studied. With pre‐acting control, the isolation system begins to respond to an impact before this impact has been applied to the base. The limiting performance of the isolator with pre‐acting control is investigated for a single‐degree‐of‐freedom system subject to an instantaneous impact. The isolation performance index is defined as the maximum of the absolute value of the displacement of the object to be isolated relative to the base, provided that the magnitude of the control force transmitted to the object does not exceed a prescribed value. It is shown that there is a substantial advantage in the use of pre‐acting isolators over isolators without pre‐action. Particular attention is given to a pre‐acting isolator based on a passive elastic element (a spring) separating the object to be protected from the base. An example illustrates the calculation of the design parameters of such an isolator.