bluuebunny/crossref_metadata_2025 huggingface dataset:
Review: Fifty Years Plus of Accelerometer History for Shock and Vibration (1940–1996)
Authors: Walter Patrick L.
Published: January 2014

This article summarizes the history of accelerometer development and the subsequent evolution of the commercial accelerometer industry. The focus is primarily on piezoelectric and piezoresistive accelerometers, although early resistance‐bridge‐type accelerometers are also described. The pioneer accelerometer manufacturing companies are identified and a chronology of technology development through today is presented.
Evaluation of the Methods for Response Analysis under Non‐Stationary Excitation
Authors: Jangid R.S. , Datta T.K.
Published: January 2014

Response of structures to non‐stationary ground motion can be obtained either by the evolutionary spectral analysis or by the Markov approach. In certain conditions, a quasi‐stationary analysis can also be performed. The first two methods of analysis are difficult to apply for complex situations such as problems involving soil‐structure interaction, non‐classical damping and primary‐secondary structure interaction. The quasi‐stationary analysis, on the other hand, provides an easier solution procedure for such cases. Here‐in, the effectiveness of the quasi‐stationary analysis is examined with the help of the analysis of a single degree‐of‐freedom (SDOF) system under a set of parametric variations. For this purpose, responses of the SDOF system to uniformly modulated non‐stationary random ground excitation are obtained by the three methods and they are compared. In addition, the relative computational efforts for different methods are also investigated.
Induction of a Transient Dysexecutive Syndrome in Parkinson’s Disease using a~Subclinical Dose of Scopolamine
Authors: Bédard M. A. , Lemay S. , Gagnon J. F. , Masson H. , Paquet F.
Published: January 2014

Parkinson’s Disease (PD) is often associated with a subcortico‐frontal syndrome (SCFS) that is mainly characterized by executive dysfunctions. The complete biochemistry of these dysfunctions remain misunderstood although many studies have suggested a role of the dopaminergic lesions. However, cholinergic lesions in this disease may also account for the SCFS occurrence. The present study has assessed the effects of an acute subclinical dose of scopolamine in normal controls and in PD patients who were devoid of cognitive deficit. Results indicates that PD patients but not normal controls developed a transient SCFS for the duration of the drug action. In contrast to other populations with cholinergic depletions—such as Alzheimer’s disease—cholinergic blockage in PD exacerbates specifically the dysexecutive syndrome without inducing amnesia or sedation. Such a discrepancy between these two neuropsychological profiles are discussed in terms of the specificity of the underlying cholinergic lesions.
Development of an Equivalent Force Method and an Application in Simulating the Radiated Noise from an Operating Diesel Engine
Authors: Vlahopoulos Nickolas , Kalish Yury , Raveendra S.T.
Published: January 2014

In this paper a new methodology is presented for applying measured accelerations and forces as excitation on a structural finite element model in order to perform a forced frequency response analysis. The computed vibration constitutes the excitation for an acoustic boundary element analysis. The new developments presented in this paper are associated with: the equivalent force method that can prescribe the acceleration at certain parts of the structure; the integration within a single process of test data that define the excitation, with the vibration analysis, and the acoustic prediction; the utilization of the new technology in simulating the noise radiated from a running engine and determining the effects of design changes. Numerical results for noise radiated from a running engine are compared to test data for a baseline design. The effect of two structural design modifications on the radiated noise is computed, and conclusions are deduced.
Speech Impairment in a Large Sample of Patients with Parkinson’s Disease
Authors: Ho Aileen K. , Iansek Robert , Marigliani Caterina , Bradshaw John L. , Gates Sandra
Published: January 2014

This study classified speech impairment in 200 patients with Parkinson’s disease (PD) into five levels of overall severity and described the corresponding type (voice, articulation, fluency) and extent (rated on a five‐point scale) of impairment for each level. From two‐minute conversational speech samples, parameters of voice, fluency and articulation were assessed by two trained‐raters. Voice was found to be the leading deficit, most frequently affected and impaired to a greater extent than other features in the initial stages. Articulatory and fluency deficits manifested later, articulatory impairment matching voice impairment in frequency and extent at the ‘Severe’ stage. At the final stage of `Profound′ impairment, articulation was the most frequently impaired feature at the lowest level of performance. This study illustrates the prominence of voice and articulatory speech motor control deficits, and draws parallels with deficits of motor set and motor set instability in skeletal controls of gait and handwriting.
Finite Element Vibration Analysis of Laminated Composite Folded Plate Structures
Authors: Guha Niyogi A. , Laha M.K. , Sinha P.K.
Published: January 2014

A nine‐noded Lagrangian plate bending finite element that incorporates first‐order transverse shear deformation and rotary inertia is used to predict the free and forced vibration response of laminated composite folded plate structures. A 6 × 6 transformation matrix is derived to transform the system element matrices before assembly. The usual five degrees‐of‐freedom per node is appended with an additional drilling degree of freedom in order to fit the transformation. The present finite element results show good agreement with the available semi‐analytical solutions and finite element results. Parametric studies are conducted for free and forced vibration analysis for laminated folded plates, with reference to crank angle, fibre angle and stacking sequence. The natural frequencies and mode shapes, and forced vibration responses furnished here may serve as a benchmark for future investigations.
Tensile Properties of Very‐High‐Strength Concrete for Penetration‐Resistant Structures
Authors: O’Neil E.F. , Neeley B.D. , Cargile J.D.
Published: January 2014

This paper describes the potential suitability of a new family of concrete mixtures for use in protective structures. Two very‐high‐strength concrete mixtures are discussed and experimental results of penetration studies on one of these are presented. The results are compared to penetration‐study results of other, more conventional concrete mixtures, and the advantages of the very‐high‐strength mixtures are described.
On the Optimal Shock Isolation of a System with One and a Half Degrees of Freedom
Authors: Balandin D.V. , Bolotnik N.N. , Pilkey W.D.
Published: January 2014

The limiting performance of shock isolation of a system with one and a half degrees of freedom is studied. The possibility of using a single‐degree‐of‐freedom model for this analysis is investigated. The error of such an approximation is estimated. Numerical examples are presented.
Dynamic Load on a Pipe Caused by Acetylene Detonations – Experiments and Theoretical Approaches
Authors: Sperber Axel , Schildberg Hans-Peter , Schlehlein Steven
Published: January 2014

The load acting on the wall of a pipe by a detonation, which is travelling through, is not yet well characterized. The main reasons are the limited amount of sufficiently accurate pressure time history data and the requirement of considering the dynamics of the system. Laser vibrometry measurements were performed to determine the dynamic response of the pipe wall on a detonation. Different modelling approaches were used to quantify, theoretically, the radial displacements of the pipe wall. There is good agreement between measured and predicted values of vibration frequencies and the propagation velocities of transverse waves. Discrepancies mainly due to wave propagation effects were found in the amplitudes of the radial velocities. They might be overcome by the use of a dynamic load factor or improved modelling methods.
Psychiatric Illness and Behavioural Problems in Adults with Learning Disability and Epilepsy
Authors: Deb Shoumitro , Joyce Joseph
Published: January 2014

We retrospectively collected data on the rate and type of psychiatric illness and behavioural problems on 143 adults with learning disability and epilepsy. 55% behavioural problems. 19% verbal aggression and temper tantrums, and 13% injurious behaviour. The overall rates of behavioural problems and different types of behaviours found in the current study cohort are similar to what was found before in learning disabled adults in general, as well as in epileptic and non‐epileptic learning disabled adults. Psychiatric diagnosis was made in 12.6% combined diagnosis of schizophrenia, delusional disorder and schizo‐affective disorder was most common (5%) diagnosis of depressive episode (3%) bipolar affective disorder.
Using Abductive Machine Learning for Online Vibration Monitoring of Turbo Molecular Pumps
Authors: Abdel-Aal R.E. , Raashid M.
Published: January 2014

Turbo molecular vacuum pumps constitute a critical component in many accelerator installations, where failures can be costly in terms of both money and lost beam time. Catastrophic failures can be averted if prior warning is given through a continuous online monitoring scheme. This paper describes the use of modern machine learning techniques for online monitoring of the pump condition through the measurement and analysis of pump vibrations. Abductive machine learning is used for modeling the pump status as ‘good’ or ‘bad’ using both radial and axial vibration signals measured close to the pump bearing. Compared to other statistical methods and neural network techniques, this approach offers faster and highly automated model synthesis, requiring little or no user intervention. Normalized 50‐channel spectra derived from the low frequency region (0–10 kHz) of the pump vibration spectra provided data inputs for model development. Models derived by training on only 10 observations predict the correct value of the logical pump status output with 100% accuracy for an evaluation population as large as 500 cases. Radial vibration signals lead to simpler models and smaller errors in the computed value of the status output. Performance is comparable with literature data on a similar diagnosis scheme for compressor valves using neural networks.
The Ability to Orient Attention in Gilles de la Tourette Syndrome
Authors: Howells Debra , Georgiou-Karistianis Nellie , Bradshaw John
Published: January 2014

Gilles de la Tourette syndrome is characterised by tics, although patients also commonly present with attentional problems. This experiment aimed to ascertain whether TS patients have problems in orienting attention, via the use of a vibrotactile choice reaction time task. Participants were required to push a button in response to a faint vibration delivered to the index finger. Prior to each stimulus vibration, a pre‐cue (valid, neutral or invalid) was administered to the finger. The performance benefits and costs participants gained from valid and invalid precues were calculated. Contrary to our prediction TS patients did not show significantly different costs or benefits. Furthermore, both patients and controls showed an equal and increased benefit in the crossed arm posture, compared to the uncrossed. These results suggest TS patients do not generally have problems in orienting attention. In addition, in the tactile modality, both patients and controls may benefit from directed attention when difficulty levels are maximal.
A Dynamic Branch‐Switching Method for Parametrically Excited Systems
Authors: Leung A.Y.T. , Ge T.
Published: January 2014

The branch‐switching algorithm in static is applied to steady state dynamic problems. The governing ordinary differential equations are transformed to nonlinear algebraic equations by means of harmonic balance method using multiple frequency components. The frequency components of the (irrational) nonlinearity of oscillator are obtained by Fast Fourier Transform and Toeplitz Jacobian method (FFT/TJM). All singularities, folds, flips, period doubling and period bubbling, are computed accurately in an analytical manner. Coexisting solutions can be predicted without using initial condition search. The consistence of both stability criteria in time and frequency domains is discussed. A highly nonlinear parametrically excited system is given as example. All connected solution paths are predicted.
Review: Hydrocodes for Structural Response to Underwater Explosions
Authors: Mair Hans U.
Published: January 2014

The applicability of the various hydrocode methodologies (Lagrangian, Eulerian, Coupled Eulerian–Lagrangian, and Arbitrary Lagrangian–Eulerian) for structural response to underwater explosions is reviewed. Only codes employing “structural elements” are realistically applicable to the analysis of thin‐walled structural response to underwater explosions.
Neurotoxic Dorsal CA1 Lesions versus 4 VO Ischaemic Lesions: Behavioural Comparisons
Authors: Nunn J. A. , Gray J. A. , Hodges H.
Published: January 2014

Anterograde amnesia, a common consequence of transient cerebral ischaemia, has been attributed to cell loss in the hippocampal CA1 subfield. However, variable, widespread damage outside hippocampal CA1 can also occur following ischaemia. We compared the functional consequences of ischaemia and ibotenate acid CA1 lesions on 2 spatial memory tasks (water maze ‘place’ and ‘matching‐to‐position’) to address the possibility that extra‐CA1 loss contributes to ischaemia‐induced memory deficits in the rat. During place task acquisition, ischaemic rats showed deficits on more measures than ibotenic rats, and during a 1 min probe trial, only ischaemic rats were impaired. On the matching‐to‐position task, ibotenic rats showed greater impairment than ischaemic rats in terms of one‐trial learning, whereas ischaemic rats were more impaired after Trial 2. Ischaemia and ibotenic acid lesions resulted in equivalent CA1 loss, but silver impregnation revealed additional extra‐CA1 cell loss in ischaemic rats. Together with the greater behavioural deficits of ischaemic rats, these data indicate a role for extra‐CA1 cell loss in ischaemia‐induced memory impairments in both animals and humans.
Neurological Soft Signs in Obsessive Compulsive Disorder: Standardised Assessment and Comparison with Schizophrenia
Authors: Bolton D. , Gibb W. , Lees A. , Raven P. , Gray J. A. , Chen E. , Shafran R.
Published: January 2014

While several studies have detected raised levels of neurological soft signs in patients with obsessive compulsive disorder (OCD), the specificity of these abnormalities remains uncertain. This study used a new standardised measure, the Cambridge Neurological Inventory (CNI), to assess soft signs in 51 subjects with OCD. Comparison was made with data on patients with schizophrenia and a non‐clinical control group from a previously reported study. Individuals with OCD showed raised levels of soft signs compared with non‐clinical controls in many categories of the CNI: Motor Coordination, Sensory Integration, Primitive Reflexes, Extrapyramidal Signs, and Failure of Suppression. Compared with patients with schizophrenia, the OCD group had lower levels of neurological signs in some CNI categories: Hard Signs, Motor Co‐ordination, Tardive Dyskinesia, Catatonic Signs, and Extrapyramidal Signs. However, levels of soft signs in the OCD group did not significantly differ from those in the schizophrenia group in other CNI categories: Sensory Integration, Primitive Reflexes and Failure of Suppression. The significance of these patterns of findings is discussed.
Response of Empty and Fluid‐Filled, Submerged Spherical Shells to Plane and Spherical, Step‐Exponential Acoustic Waves
Authors: Sprague Michael A. , Geers Thomas L.
Published: January 2014

The title problem is solved through extension of a method previously formulated for plane step‐wave excitation, which employs generalized Fourier series augmented by partial closure of those series at early time. The extension encompasses both plane and spherical incident waves with step‐exponential pressure profiles. The effects of incident‐wave curvature and profile decay rate on response behavior are examined. A method previously developed for assessing the discrepancy between calculated and measured response histories is employed to evaluate the convergence of the truncated series solutions. Also studied is the performance of doubly‐asymptotic approximations. Finally, the efficacy of modified Cesàro summation for improving the convergence of series solutions is examined. The documented computer program that produced the numerical results appearing in this paper, SPHSHK/MODSUM, may be down‐loaded from the Web site http://saviac.xservices.com.
Dynamic Measurements of Plastic Deformation in a Water‐Filled Aluminum Tube in Response to Detonation of a Small Explosives Charge
Authors: Sandusky Harold , Chambers Paul , Zerilli Frank , Fabini Larry , Gottwald William
Published: January 2014

Experiments have been conducted to benchmark computer code calculations for the dynamic interaction of explosions in water with structures. Aluminum cylinders with a length slightly more than twice their diameter were oriented vertically, sealed on the bottom by a thin plastic sheet, and filled with distilled water. An explosive charge suspended in the center of the tube plastically deformed but did not rupture the wall. Tube wall velocity, displacement, and strain were directly measured. The agreement among the three sets of dynamic data and the agreement of the terminal displacement measurements with the residual deformation were excellent.
An Evolutionary Hypothesis for Obsessive Compulsive Disorder: A Psychological Immune System?
Authors: Abed Riadh T. , de Pauw Karel W.
Published: January 2014

A new hypothesis is presented within the framework of evolutionary psychology that attempts to explain the origins of obsessive‐compulsive disorder. It is suggested that obsessions and compulsions originate from the overactivity of a mental module that the majority of humans possess and has the function of generating risk scenarios without voluntary intervention. It is hypothesised that obsessional phenomena function as an off‐line risk avoidance process, designed to lead to risk avoidance behaviour at a future time, thus distinguishing it from anxiety and related phenomena as on‐line emotional states, designed to lead to the avoidance of immediate and direct risks. Finally, the hypothesis makes a number of specific predictions that are testable and refutable. It is contended that the present hypothesis if supported by empirical evidence could serve as a basis for future research on this important disorder.
Finite Element Vibration Analysis of Beams, Plates and Shells
Authors: Mackerle Jaroslav
Published: January 2014

This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element vibration analysis of beams, plates and shells that were published in 1994–1998. It contains 361 citations. Also included, as separated subsections, are vibration analysis of composite materials and vibration analysis of structural elements with cracks/contacts.
Rest‐to‐Rest Attitude Naneuvers and Residual Vibration Reduction of a Finite Element Model of Flexible Satellite by Using Input Shaper
Authors: Parman Setyamartana , Koguchi Hideo
Published: January 2014

A three‐dimensional rest‐to‐rest attitude maneuver of flexible spacecraft equipped by on‐off reaction jets is studied. Equations of motion of the spacecraft is developed by employing a hybrid system of coordinates and Lagrangian formulation. The finite element method is used to examine discrete elastic deformations of a particular model of satellite carrying flexible solar panels by modelling the panels as flat plate structures in bending. Results indicate that, under an unshaped input, the maneuvers induce undesirable attitude angle motions of the satellite as well as vibration of the solar panels. An input shaper is then applied to reduce the residual oscillation of its motion at several natural frequencies in order to get an expected pointing precision of the satellite. Once the shaped input is given to the satellite, the performance improves significantly.
Characterization and Simulation of Gunfire with Wavelets
Authors: Smallwood David O.
Published: January 2014

Gunfire is used as an example to show how the wavelet transform can be used to characterize and simulate nonstationary random events when an ensemble of events is available. The structural response to nearby firing of a high‐firing rate gun has been characterized in several ways as a nonstationary random process. The current paper will explore a method to describe the nonstationary random process using a wavelet transform. The gunfire record is broken up into a sequence of transient waveforms each representing the response to the firing of a single round. A wavelet transform is performed on each of these records. The gunfire is simulated by generating realizations of records of a single‐round firing by computing an inverse wavelet transform from Gaussian random coefficients with the same mean and standard deviation as those estimated from the previously analyzed gunfire record. The individual records are assembled into a realization of many rounds firing. A second‐order correction of the probability density function is accomplished with a zero memory nonlinear function. The method is straightforward, easy to implement, and produces a simulated record much like the measured gunfire record.
Benchmarks for Submerged Structure Response to Underwater Explosions
Authors: Mair Hans U.
Published: January 2014

Benchmarks for submerged structure response to underwater explosions (UNDEX) are compiled. Both analytical and empirical benchmarks are presented; each type has advantages and disadvantages for the purposes of model validation, though no methodology for employing these benchmarks in a model validation effort is proposed. Benchmark computations are also referenced as part of this compilation. Finally, extension of this compilation to the UNDEX response of internal equipment and floating structures, and to hydrodynamic/hydraulic ram problems, is proposed.
A Comparison of Simulation’s Results with Experiment on Water Mitigation of an Explosion
Authors: Chong W.K , Lam K.Y. , Yeo K.S. , Liu G.R. , Chong O.Y.
Published: January 2014

This paper presents a comparison of simulation’s results with the experimental data from a series of small‐scale tests conducted by Joachim and Lunderman of the United States Army Engineer Waterways Experiment Station. The purpose of the experiments was to evaluate the effect of water as a mean of reducing airblast pressure from accidental explosions in underground magazines. In the present study, a series of three‐dimensional numerical calculations were conducted using a Multimaterial Eulerian Finite Element Code. Results from the numerical simulations show good comparison with the experimental data for the case with and without water. Our simulation ascertains the mitigation effects of water in reducing the maximum peak pressure and impulse density due to an explosion.
Improvement of Mental Imagery after Prism Exposure in Neglect: A Case Study
Authors: Rode Gilles , Rossetti Yves , Li Ling , Boisson Dominique
Published: January 2014

Previous work has shown that various symptoms of unilateral neglect, including the pathological shift of the subjective midline to the right, may be improved by a short adaptation period to a prismatic shift of the visual field to the right. We report here the improvement of imagined neglect after prism exposure in a patient with a left unilateral neglect. Despite a strong neglect observed for mental images as well as for conventional tests, the mental evocation of left‐sided information from an internal image of the map of France map was fully recovered following prism adaptation to the right. This improvement could not be explained by the alteration of visuomotor responses induced by the prism adaptation. Prism adaptation may therefore act not only on sensory‐motor levels but also on a higher cognitive level of mental space representation and/or exploration.
Finite Element Crash Simulations and Impact‐Induced Injuries
Authors: Mackerle Jaroslav
Published: January 2014

This bibliography lists references to papers, conference proceedings and theses/dissertations dealing with finite element simulations of crashes, impact‐induced injuries and their protection that were published in 1980–1998. 390 citations are listed.
Intellectual, Mnemonic, and Frontal Functions in Dementia with Lewy Bodies: A Comparison with Early and Advanced Parkinson’s Disease
Authors: Downes John Joseph , Priestley Nicholas M. , Doran Mark , Ferran Jose , Ghadiali Eric , Cooper Paul
Published: January 2014

Both Parkinson’s disease (PD) and dementia with Lewy bodies (DLB) share a common neuropathological marker, the presence of Lewy bodies in brain stem and basal forebrain nuclei. DLB, in addition, is associated with Lewy bodies in the neocortex, and, in it’s more common form, with Alzheimer‐type pathological markers, particularly amyloid plaques. Published neuropsychological studies have focused on the differential profiles of DLB and Alzheimer’s disease (AD). However, it is presently unclear whether DLB should be classified as a variant of AD or PD. In the present study we compare a healthy age‐matched control group with three groups of patients, one with DLB, and two with PD. One of the PD groups was early in the course (PD‐E) and the second, more advanced group (PD‐A), was matched on severity of cognitive impairment with the DLB group. The results show that DLB was associated with a different pattern of neuropsychological impairment than the PD‐A group, particularly in tests believed to be mediated by prefrontal cortical regions.
Role of the Striatum and the Cerebellum in Motor Skill Acquisition
Authors: Schugens Markus M. , Breitenstein Caterina , Ackermann Hermann , Daum Irene
Published: January 2014

Motor skill acquisition was investigated in patients with Parkinson′s disease (PD) or cerebellar dysfunction using two sensory‐guided tracking tasks. The subjects had to learn to track a visual target (a square) on a computer screen by moving a joystick under two different conditions. In the unreversed task, the horizontal target movements were semi‐predictable and could be anticipated. In the reversed task, the horizontal movements of a pointer which had to be kept within the target square were mirror‐reversed to the joystick movements. PD patients showed intact learning of the semi‐predictable task and reduced learning of the mirror‐reversed task; patients with cerebellar dysfunction showed the opposite pattern. These findings are discussed in relation to the differential contribution of the cerebellum and the striatum to motor skill acquisition: the cerebellum appears to participate in the implementation of anticipatory movements, whereas the striatum may be critically involved in types of motor learning which require a high degree of internal elaboration.
Storage of Verbal Associations Is Sufficient to Activate the Left Medial Temporal Lobe
Authors: Mayes Andrew R. , Gooding Patricia A. , Hunkin Nicola M. , Nunn Julia A. , Gregory Lloyd J. , Brammer Michael J. , Bullmore Edward T. , Giampietro Vincent , Van Eijk Rob , Nicholas Amanda K. , Williams Steve C. R.
Published: January 2014

Neuroimaging studies have shown that memory encoding activates the medial temporal lobe (MTL). Many believe that these activations are related to novelty but it remains unproven which is critical ‐ novelty detection or the rich associative encoding it triggers. We examined MTL activation during verbal associative encoding using functional magnetic resonance imaging. First, associative encoding activated left posterior MTL more than single word encoding even though novelty detection was matched, indicating not only that associative encoding activates the MTL particularly strongly, but also that activation does not require novelty detection. Moreover, it remains to be convincingly shown that novelty detection alone does produce such activation. Second, repetitive associative encoding produced less MTL activation than initial associative encoding, indicating that priming of associative information reduces MTL activation. Third, re‐encoding familiar associations in a well‐established way had a minimal effect on both memory and MTL activation, indicating that MTL activation reflects storage of associations, not merely their initial representation.
Decreased Volume of the Cerebral Ventricles on CT Images in Gilles de la Tourette’s Syndrome
Authors: Regeur Lisbeth , Korbo L. , Bang N. , Pakkenberg B.
Published: January 2014

The aim of the present study was to estimate the volume of the ventricular system comprising lateral plus third ventricles in patients with Gilles de la Tourette′s syndrome on computed tomographic (CT) scannings using unbiased stereological principles and to compare that volume with a control group. We found a significantly reduced ventricular volume in 24 patients with Gilles de la Tourette′s syndrome (GTS) compared with 28 controls.
Response Measurements on an Echinodome Subjected to Explosive Loading
Authors: El-Deeb K.M.M. , Royles R.
Published: January 2014

Free field explosion experiments were carried out to determine the general characteristics of the pressure pulse generated by a detonator underwater. An echinodome – an axisymmetric shell structure of optimum form – was subjected to a shock wave from the same type of detonator, the structure being in a floating submerged and tethered state. Some indication of the influence of the structure on the incident pressure wave was obtained from a surface mounted miniature pressure gage. Structural response was measured with the aid of strain gages from which principal stress data were deduced. Consideration was given to the theoretical modelling aspects of the problem.
Non‐Linear Response of Light Equipment System in a Torsional Building to Bi‐Directional Ground Excitation
Authors: Agrawal Abhijit K.
Published: January 2014

Dynamic response of a light equipment item attached to a non‐linear and torsionally coupled main system is evaluated under bi‐directional earthquake excitation. To account for the effect of translations and torsion, each story of the building is modelled as three degrees‐of‐freedom (DOFs), with two DOFs for translation in two orthogonal directions and third DOF for torsion. The responses (relative displacement between the equipment system and the floor of the primary system on which the equipment system is mounted and absolute acceleration of the equipment system itself), are determined under random ground motion in two orthogonal directions, which is idealized as a stationary random process represented by a white noise excitation. The responses are obtained by time domain simulation procedure. The response behavior of the light equipment is examined under a set of parametric variations. These parameters include the uncoupled lateral frequency of the primary and the equipment systems, the ratio of uncoupled lateral to rotational frequencies of the primary system, eccentricity ratios of the primary and the equipment systems in X and Y directions, damping ratio of the primary and the equipment systems and the mass ratio of the two systems. Results of the study indicate that under some parametric conditions the responses of the equipment system are significantly affected by torsional coupling and non‐linearity of the primary system. It is also observed that the responses of the equipment system can be alleviated by increasing the damping ratio of the equipment system.
Self and Body Esteem Perception in Multiple Sclerosis
Authors: Barak Yoram , Lampl Yair , Sarova-Pinchas Ida , Achiron Anat
Published: January 2014

Self esteem and body esteem were examined in a group of 35 relapsing‐remitting multiple sclerosis (MS) patients using the Body Esteem Scale (BES) and the Eysenck Self Esteem Scale (ESES) and compared to age and sex matched normal controls.

There were 23 females and 12 males in the MS patient’s group; average age 38.9 years (range: 22–52). All participants completed the self‐rated BES evaluating the following subscales: females—sexual attractiveness, physical condition and weight concern; males—physical attractiveness, physical condition and upper body strength. In addition all participants were scored, following a semi‐structured interview, on the ESES. Psychiatric co‐morbidity was excluded using a semi‐structured interview by the consulting psychiatrist. All evaluations were carried out during the remitting phase. Statistical analysis, comparing patients to healthy controls, demonstrated lowered self‐rating of the physical condition (males < 0.05, females < 0.001). On the other hand, no significant differences were found in the physical (male) or sexual (female)—attractiveness subscales. The mean ESES score in the patients group was 23.2 ± 4.0, slightly above the reported average. The controls mean ESES was 28.4 ± 3.6, (P < 0.05). No correlation was found between self and body esteem amongst M.S. patients. This study emphasizes impaired perception of body esteem in multiple sclerosis patients even in remission. The preservation of physical and sexual attractiveness may be related to the non‐disfiguring nature of the disease. Preservation of self‐esteem in MS patients suggests that body‐esteem should be the focus of supportive treatment.
Fluid‐Structure Interaction Mechanisms for Close‐In Explosions
Authors: Wardlaw Andrew B. , Luton J. Alan
Published: January 2014

This paper examines fluid‐structure interaction for close‐in internal and external underwater explosions. The resulting flow field is impacted by the interaction between the reflected explosion shock and the explosion bubble. This shock reflects off the bubble as an expansion that reduces the pressure level between the bubble and the target, inducing cavitation and its subsequent collapse that reloads the target. Computational examples of several close‐in interaction cases are presented to document the occurrence of these mechanisms. By comparing deformable and rigid body simulations, it is shown that cavitation collapse can occur solely from the shock‐bubble interaction without the benefit of target deformation. Addition of a deforming target lowers the flow field pressure, facilitates cavitation and cavitation collapse, as well as reducing the impulse of the initial shock loading.
Laser Measurement of Building Vibration and Displacement
Authors: Bougard A.J. , Ellis B.R.
Published: January 2014

This paper considers four laser systems used by the Building Research Establishment (BRE) to investigate the behaviour of structures. Lasers enable remote measurements of vibration and displacement to be taken where access to a structure is difficult or where fire, explosion or structural collapse creates a hazardous environment. Each system will be described, and its use illustrated using measurements taken on real structures.

The four systems are:

1. Laser Interferometer: This is used to measure the velocity of vibration of a structure under ambient loading.

2. 3D‐Laser Survey System: This is used to track the movement of any number of targets on a structure under load.

3. VHS Laser System: This is used to measure displacement of a target moving at high velocities.

4. Tracking Lasers: This is used to track the angular displacements of a target.
Variable Modal Parameter Identification for Non‐Linear Mdof Systems. Part II: Experimental Validation and Advanced Case Study
Authors: Chong Y.H. , Imregun M.
Published: January 2014

The purpose of Part II is to provide an experimental validation of the methodology presented in Part I and to consider a representative engineering case, the study of which requires a relatively large numerical model. A beam system with cubic stiffness type non‐linearity was used in the experimental study. The non‐linear response was measured at three locations and the underlying linear system was obtained via linear modal analysis of low‐excitation response data. The non‐linear parameter variations were obtained as a function of the modal amplitude and the response of the system was generated for other force levels. The results were found to agree very well with the corresponding measurements, indicating the success of the non‐linear modal analysis methodology, even in the presence of true experimental noise. An advanced numerical case study that included both inherent structural damping and non‐linear friction damping, was considered next. The linear finite element model of a high‐pressure turbine blade was used in conjunction with three local non‐linear friction damper elements. It was shown that the response of the system could be predicted at any force level, provided that that non‐linear modal parameters were available at some reference force level. The predicted response levels were compared against those obtained from reference simulations and very good agreement was achieved in all cases.
High Efficiency Computation of the Variances of Structural Evolutionary Random Responses
Authors: Lin J.H. , Sun D.K. , Zhong W.X. , Zhang W.S.
Published: January 2014

For structures subjected to stationary or evolutionary white/colored random noise, their various response variances satisfy algebraic or differential Lyapunov equations. The solution of these Lyapunov equations used to be very difficult. A precise integration method is proposed in the present paper, which solves such Lyapunov equations accurately and very efficiently.
Probing Cortical Sites of Antipsychotic Drug Action with in vivo Receptor Imaging
Authors: Shaw P. , Pilowsky L. S.
Published: January 2014

Imaging receptors using radioactive ligands has allowed direct determination of the sites of action of antipsychotic drugs. Initial studies relating antipsychotic drug efficacy to action at striatal dopamine D2‐like receptors have recently been undermined. Developments in imaging extrastriatal dopamine D2‐like receptors suggest rather that antagonism of these receptors in the temporal cortex is the common site of action for antipsychotic drugs, with occupancy at striatal receptors relating more closely to extrapyramidal side effects. Further work into dopamine receptor subtypes and other receptor groups such as serotonin and GABA neurotransmitters awaits the development of suitable probes, but there are some initial finding. Again a main site of antipsychotic drug action is at cortical levels with high degrees of cortical D1 and 5HT2a receptor occupancy attained particularly by atypical antipsychotic drugs.
Measuring Spatial Vibration Using Continuous Laser Scanning
Authors: Bucher Izhak , Wertheim Oded
Published: January 2014

This paper presents a method, which allows one to use a single point laser vibrometer as a continuous sensor measuring along a line or a 2D surface. The mathematical background of the curve‐fitting procedure and the necessary signal processing allowing one to extract the amplitude of sinusoidal vibration are discussed. In the current work, use has been made with an ordinary laser interferometer equipped with glavanometer‐based x, y mirros. This system is not designed for continuous scanning therefore some effort needs to be spent in order to overcome the dynamical characteristics of this system. The potential of such an instrument, as demonstrated in this work, may encourage the development of mechanically better scanning devices.
Right Amygdalar and Temporofrontal Activation During Autobiographic, But Not During Fictitious Memory Retrieval
Authors: Markowitsch Hans J. , Thiel Alexander , Reinkemeier Mechthild , Kessler Josef , Koyuncu Adem , Heiss Wolf-Dieter
Published: January 2014

What distinguishes the recall of real‐life experiences from that of self‐created, fictitious emotionally laden information? Both kinds of information belong to the episodic memory system. Autobiographic memories constitute that part of the episodic memory system that is composed of significant life episodes, primarily of the distant past. Functional imaging was used to study the neural networks engaged in retrieving autobiographic and fictitious information of closely similar content. The principally activated brain regions overlapped considerably and constituted temporal and inferior prefrontal regions plus the cerebellum. Selective activations of the right amygdala and the right ventral prefrontal cortex (at the level of the uncinate fascicle interconnnecting prefrontal and temporopolar areas) were found when subtracting fictitious from autobiographic retrieval. Furthermore, distinct foci in the left temporal lobe were engaged. These data demonstrate that autobiographic memory retrieval uses (at least in non‐brain damaged individuals) a network of right hemispheric ventral prefrontal and temporopolar regions and left hemispheric lateral temporal regions. It is concluded that it is the experiential character, its special emotional infiltration and its arousal which distinguishes memory of real‐life from that of fictitious episodes. Consequently, our results point to the engagement of a bi‐hemispheric network in which the right temporo‐prefrontal hemisphere is likely to be responsible for the affective/arousal side of information retrieval and the left‐hemispheric temporal gyrus for its engram‐like representation. Portions of the neural activation found during retrieval might, however, reflect re‐encoding processes as well.
Is the Finding of Obsessional Behaviour Relevant to the Differental Diagnosis of Vascular Dementia of the Binswanger Type?
Authors: Lawrence Robert M.
Published: January 2014

Whilst carrying out a pilot study with a structured questionnaire examining the difference in insight between a group of patients with Alzheimer’s Disease and a second group with Vascular Dementia of the Binswanger Type, the incidental observation was made that the group of patients with Vascular Dementia of the Binswanger Type demonstrated more obsessional behaviour than the group of patients with Alzheimer’s Disease. The obsessional behaviour differed from classical obsessive compulsive disorder insofar as the subjects were unaware of it whilst at the same time resisting change.
Memory and Executive Function Impairments after Frontal or Posterior Cortex Lesions
Authors: Daum Irene , Mayes Andrew R.
Published: January 2014

Free recall and recognition, memory for temporal order, spatial memory and prospective memory were assessed in patients with frontal lobe lesions, patients with posterior cortex lesions and control subjects. Both patient groups showed equivalent memory deficits relative to control subjects on a range of free recall and recognition tasks, on memory for temporal order and on a prospective memory task. The patient groups also performed equivalently on the spatial memory task although only patients with frontal lobe lesions were significantly impaired. However, the patients with frontal lobe lesions showed an increased false alarm rate and made more intrusion errors relative not only to the control subjects, but also to the patients with poster or cortex lesions. These memory problems are discussed in relation to deficits in executive function and basic memory processes.
Measurement of Rotorcraft Blade Deformation Using Projection Moiré Interferometry
Authors: Fleming Gary A. , Gorton Susan Althoff
Published: January 2014

Projection Moiré Interferometry (PMI) has been used to obtain near instantaneous, quantitative blade deformation measurements of a generic rotorcraft model at several test conditions. These laser‐based measurements provide quantitative, whole field, dynamic blade deformation profiles conditionally sampled as a function of rotor azimuth. The instantaneous nature of the measurements permits computation of the mean and unsteady blade deformation, blade bending, and twist. The PMI method is presented, and the image processing steps required to obtain quantitative deformation profiles from PMI interferograms are described. Experimental results are provided which show blade bending, twist, and unsteady motion. This initial proof‐of‐concept test has demonstrated the capability of PMI to acquire accurate, full field rotorcraft blade deformation data.
Study of Dynamic Characteristics of Slow‐Changing Process
Authors: Li Yinong , Zheng Ling , Wen Bangchun
Published: January 2014

A vibration system with slow‐changing parameters is a typical nonlinear system. Such systems often occur in the working and controlled process of some intelligent structures when vibration and deformation exist synchronously. In this paper, a system with slow‐changing stiffness, damping and mass is analyzed in an intelligent structure. The relationship between the amplitude and the frequency of the system is studied, and its dynamic characteristic is also discussed. Finally, a piecewise linear method is developed on the basis of the asymptotic method. The simulation and the experiment show that a suitable slow‐changing stiffness can restrain the amplitude of the system when the system passes through the resonant region.
The Effective Design of Bean Bag as a Vibroimpact Damper
Authors: Liu A.Q. , Wang B. , Choo Y.S. , Ong K.S.
Published: January 2014

The technique of a bean bag damper has been effectively applied in many engineering fields to control the vibroimpact of a structural system. In this study, the basic parameters responsible for the design of an effective bean bag: the size of beans, the mass ratio of the bean bag to the structure to which it is attached, the clearance distance and the position of the bag, are studied by both theoretical and experimental analyses. These will provide a better understanding of the performance of the bean bag for optimisation of damper design. It was found that reducing the size of beans would increase the exchange of momentum in the system due to the increase in the effective contact areas. Within the range of mass ratios studied, the damping performance of the damper was found to improve with higher mass ratios. There was an optimum clearance for any specific damper whereby the maximum attenuation could be achieved. The position of the bag with respect to nodes and antipodes of the primary structure determined the magnitude of attenuation attainable. Furthermore, the limitations of bean bags have been identified and a general criteria for the design of a bean bag damper has been formulated based on the study undertaken. It was shown that an appropriately configured bean bag damper was capable of reducing the amplitude of vibration by 80% to 90%.
The Effect of Semantic Categorisation on Recall Memory in Amnesia
Authors: Channon Shelley , Daum Irene
Published: January 2014

Amnesic patients were compared to a healthy control group on recall of word lists containing semantically‐related or unrelated words. As expected on the basis of previous literature, the amnesic group performed below the control group on all measures of recall. When total recall scores for each list were used as the index of performance, their scores were not significantly affected by the type of list, unlike those of the control group. Comparison of serial position effects for different parts of the lists revealed that the control group derived greater benefit from semantic relatedness in recall of items from the middle positions. This effect was not shown by the amnesic group, who showed similar U‐shaped serial position curves for recall of all three lists, and appeared to use a more passive recall strategy than the control group. The findings are discussed in relation to our current understanding of amnesic deficits.