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Two Images Our eyes are approximately 63 millimeters (2.5 inches) apart, which means when we look at the real world our left eye and right eye see slightly different images. [...]

The application of nonimmersive virtual reality (VR) to the creation of rich cartographic representations in 3D is a current research area in cartography. However, the cartographic knowledge needed to build these representations is lacking. The consequences of this include misconceptions in map design that can inhibit or even impair understanding of the representation. A common task in cartographic VR is virtual navigation supported by 3D topographic maps. This geographical task gathers different knowledge schema, based on the selection of specific features for use as landmarks. In VR, there is a need for adaptation of cartographic representations to improve cartographic communication. The strategy adopted in this research uses Gestalt aspects to direct the user's selective attention to features that will act as landmarks. To evaluate this proposition, we compare sketch maps from 3D and conventional 2D topographic maps made by 43 volunteers and identify which features were used as landmarks and how they were drawn in the sketch maps. The number of landmarks identified by the user, their topology and orientation, and how the symbols were drawn highlights the success of this proposal for 3D topographic maps for virtual navigation. Keywords: 3D map symbology; virtual navigation; Gestalt, Introduction One of the current research areas in cartography is the application of nonimmersive virtual reality (VR) and its effects on cartographic communication. This kind of VR has several applications, [...]

Many higher education institutions have set up virtual classrooms in the 3-D virtual world. In this research, the authors assess the relative effectiveness ofa 3-D virtual world learning environment, Second Life, compared to traditionalface-to-face learning environment. They also assess the effects of instructional strategies in these two learning environments on interactivity, perceived learning, and satisfaction. The authors 'findings suggest that learning environment interacts with instructional strategy to affect the learners 'perceived learning and satisfaction. Specifically, when interactive instructional strategy is used, there is no significant difference for perceived learning and satisfaction between the 3-D virtual world and face-to-face learning environment. However, when a direct instructional strategy is used, there is a significant difference for perceived learning and satisfaction. They also assessed whether or not technology helps increase learner and instructor interaction. The result suggests that in interactive instructional sessions, students experienced a higher level of classroom interactivity in Second Life than in face-to-face classroom. Keywords: 3-D Virtual World, Classroom Interactivity, Instructional Strategies, Perceived Ease of Use, Perceived Learning, Perceived Usefulness, Second Life, Social Presence, INTRODUCTION Delivering education over the Internet is growing in popularity and gaining in importance. Higher learning in 3-D virtual worlds is a relatively new phenomenon that has attracted much attention [...]

Simulations of plasma flow through a magnetic nozzle were conducted using the time-dependent, three-dimensional magnetohydrodynamies code MACH3. Modeling of magnetic nozzle flow using constant, classical isotropic, and classical tensor resistivity provides preliminary quantitative depiction of the core-plasma flow, evolution of the magnetic field, and conversion of stagnation enthalpy to directed exhaust thrust energy, and serves as verification for the numerical model. For stagnation conditions of 100 eV and 0.355 MPa, steady-state modeling using helium propellant demonstrates a nearly isentropic expansion through the nozzle to exhaust speeds near 160 km/s. The extent of the contribution from the magnetic diffusion and the mass-flux penetration to the thickness of the current layer strongly depends on plasma resistivity. Plasma-field interaction results in a reduction of approximately 50 % of the directed axial thrust when compared with a solid-wall nozzle of equivalent Mach number design. At fixed plasma pressure and applied field the exhaust velocity scales appropriately as the square root of the stagnation temperature. DOI: 10.2514/1.J050123

Direct injection of gaseous fuel has emerged to be a high potential strategy to tackle both environmental and fuel economy requirements. However, since the electronic gaseous injection technology is rather new for automotive applications, limited experience exists on the optimum configuration of the injection system and the combustion chamber. To facilitate the development of these applications computer models are being developed to simulate gaseous injection, air entrainment, and the ensuing combustion. This paper introduces a new method for modeling the injection process of gaseous fuels in multidimensional simulations. The proposed model allows holding down grid requirements, thus, making it compatible with the three-dimensional simulation of an internal combustion engine. [DOI: 10.1115/1.4000288]

Three-dimensional numerical simulations of the effect of fouling on an axial compressor stage were carried out. As a case study, the NASA Stage 37 was considered for the numerical investigation, which was performed by means of a commercial computational fluid dynamic code. The numerical model was validated against the experimental data available from literature. Computed performance maps and main flow field features showed a good agreement with the experimental data. The model was considered representative of a realistic compressor stage. The model was then used to simulate the occurrence of fouling by imposing different combinations of added thickness and surface roughness levels. The effect of fouling on compressor performances was studied. Reductions in the flow coefficient and in the pressure coefficient were found to be of the same order of magnitude of the experimental results found in literature. The model developed seems to overcome some of the limitations of other models found in literature that tend to significantly underestimate the actual values of performance reduction. The numerical results were also used to analyze and debug the stage performance scaling procedure used in stage-stacking models in order to represent fouling in multistage compressors. The analysis highlighted that scaling can adequately represent the behavior of the fouled stage in the choked flow region, but it does not capture the reduction in the maximum of the pressure coefficient, which is instead revealed by the numerical simulations. Finally, blockage due to fouling was investigated both qualitatively and quantitatively. [DOI: 10.1115/1.4000128]

Presently, stack dice are used widely as low-power memory applications because thermal management of 3D architecture such as high-power processors inherits many thermal challenges. Inadequate thermal management of three-dimensional integrated circuits (3D-ICs) leads to reduction in performance, reliability, and ultimately system catastrophic failure. Heat dissipation of 3D systems is highly nonuniform and nonunidirectional due to many factors such as power architectures, transistors packing density, and real estate available on the chip. In this study, the development of an experimental model of an active cooling method to cool a 25 W stack-dice to approximately 13[degrees]C utilizing a multidimensional configured thermoelectric will be presented. [DOI: 10.1115/1.4001831]

We present a method in which the 3D shape of an object can be measured and compared to the shape of the digital master of the object, e.g., the computer-aided design model. The measurement is done using a stereo camera system and a single projected fringe pattern. Because the digital master is available, i.e., the expected shape is known, only one projection and image recording is necessary; thus, the method becomes fast. The idea in this work is to find homologous points in the cameras, i.e., points corresponding to the same object point, using the object information. An algorithm to find the homologous points is presented and a method to calculate shape is described. Given the ambiguity due to the fact that the phase in the images is wrapped, there is a maximum deviation from the master that can be correctly detected. An analytical expression for this deviation is derived. Results from the shape measurement of an object both with and without deviations from the digital master are also presented. In these measurements, where the measurement volume is approximately I [dm.sup.3] and the fringe period on the object plane is about 1mm, the accuracy is [approximately equal to] [+ or -] 40 [micro]m, and a deviation of max [approximately equal to] [+ or -] 1.6mm can be correctly detected. OCIS codes: 120.2650, 120.6650, 110.6880.

A microwave oven operating at a frequency of 2.45 GHz was designed for demonstrating three-dimensional standing waves. The three-dimensional standing wave patterns formed on cobalt chloride paper placed at the center of the oven chamber were examined. The images on the cobalt chloride paper corresponding to antinodes of the standing waves were recorded by a digital camera after turning on the microwave oven. The results show that the numbers of antinodes of the standing waves in each plane agree with those of the theoretical calculation of the electric field distribution in the oven chamber. [DOI: 10.1119/1.3329286]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.12.063 Byline: Hitoshi Biwasaka (a)(e), Takuya Tokuta (a)(e), Yoshitoshi Sasaki (a)(e), Kei Sato (a)(e), Takashi Takagi (b), Toyohisa Tanijiri (c), Sachio Miyasaka (d), Masataka Takamiya (e), Yasuhiro Aoki (e) Keywords: Distortion; Surveillance camera; Computerised correction; Facial image; Superimposition Abstract: The applicability of computerised correction of optical distortion to two-dimensional (2D)/three-dimensional (3D) facial image superimposition was investigated. Two-dimensional (2D) facial images of 10 male volunteers were taken with a commercially available closed circuit device (CCD) camera (reference camera) at four areas of the lens field: the centre, top, upper right and right. Correction was made by computer by calculating differences vis-a-vis the co-ordinates of dots on a test chart. Discrepancies in facial outlines between the 3D and 2D images decreased following correction in all lens fields and were below the threshold for true positive. The correction method was also tested using an actual surveillance camera and video recorder installed in a bank. The method was found to be effective for the correction of facial images, especially those taken in the top and right lens fields. Since the total error (observed error) remaining after correction appeared close to the random error (real error), systematic error was thought to be minimised by correction. Therefore, the present method was thought to display high fidelity, and could be useful for supplementary examination of conventional superimposition. Author Affiliation: (a) Forensic Science Laboratory, Iwate Prefectural Police Headquarters, 8-10 Uchimaru, Morioka, Iwate 020-8540, Japan (b) Forensic Science Laboratory, Miyagi Prefectural Police Headquarters, 3-8-1 Honchou, Aoba-ku, Sendai, Miyagi 980-8410, Japan (c) Medic Engineering Co., 11-1 Higashihirakichou, Takano, Sakyo-ku, Kyoto 606-8107, Japan (d) National Research Institute of Police Science, 6-3-1 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan (e) Department of Legal Medicine, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan Article History: Received 13 April 2009; Revised 3 December 2009; Accepted 21 December 2009

Three-dimensional scaled-up transparent models of three human cystic ducts were prepared on the basis of anatomical specimens. The measurement of pressure drop across the cystic duct models and visualization of the flow structures within these ducts were performed at conditions replicating the physiological state. The flow visualization study confirmed the laminar nature of the flow of bile inside the cystic duct and values of pressure drop coefficient (Cp) decreased as the Reynolds number (Re) increased. The three tested models showed comparable behavior for the curve of Reynolds number versus the pressure drop coefficient. The results show that the tested cystic ducts have both increased pressure drop and complicated flow structures When compared with straight conduits. High resistance in a cystic duct may indicate that the gallbladder has to exert large force in expelling bile to the cystic duct. For patients with diseased gallbladder, and even in healthy persons, gallbladder is known to stiffen with age and it may lose its compliance or flexibility. A high resistance cystic duct coupled with a stiffened gallbladder may result in prolonged stasis of bile in the gallbladder, which is assumed to encourage the formation of gallstones. [DOI: 10.1115/1.4001043] Keywords: cystic duct, gallbladder, flow visualization, gallstones

This paper presents a fast treatment of essential boundary conditions in three-dimensional (3D) meshfree computation for computational efficiency. Due to the loss of Kronecker delta properties in the meshfree shape functions, the imposition of essential boundary conditions is tedious, especially in 3D applications. The proposed boundary singular kernel (BSK) method introduces singularities to the kernel functions associated with the essential and kinematically constrained boundary nodes so that the corresponding coefficients of the singular kernel shape functions recover nodal values, and consequently constraints can be imposed directly. In this work, the recovery of nodal value properties on essential boundary nodes is proved for general n-dimensional geometries. The extension of previously proposed two-dimensional BSK method to 3D formulation thus becomes straightforward, and essential boundary treatment consumes almost no additional cost to meshfree computation and makes the method affordable for industrial applications. The effectiveness of the proposed method is demonstrated in 3D metal forming examples. DOI: 10.1061/(ASCE)EM.1943-7889.0000026 CE Database subject headings: Mesh generation; Boundaries; Metals; Form; Computation.

A three-dimensional (3D) micromechanics-based evolutionary damage model is proposed to predict the effective elastic behavior of continuous fiber-reinforced brittle matrix composites with microcracks and imperfect interfaces. Eshelby's tensor for a circular cylindrical inclusion with slightly weakened interface is adopted to model continuous fibers with imperfect interfaces. The nucleation of microcracks is simulated by employing the continuum damage model. A multilevel damage modeling process in accordance with Weibull's probabilistic function is incorporated into the micromechanical framework to describe the sequential evolution of imperfect interfaces in the composites. Numerical examples corresponding to uniaxial loadings in the longitudinal and transverse directions are solved to illustrate the potential of the proposed damage model. Furthermore, the present prediction is compared with available experimental data in the literature to highlight the applicability of the proposed model. DOI: 10.1061/(ASCE)EM.1943-7889.0000039 CE Database subject headings: Fiber-reinforced materials; Brittleness; Composite materials; Damage; Cracking.

Understanding building envelope performance and thermal mass effects is becoming increasingly important under the scope of low energy building construction and energy conservation. In the present paper, a three-dimensional computational fluid dynamics methodology is presented for the numerical simulation of the flow and heat transfer that determine the thermal behavior of simplified building envelopes. This is dominated by a conjugate heat transfer approach, which involves conduction, convection, solar heat gains, ambient temperature variation, and the effects of thermal radiation losses to the sky. Validation results include comparison both with measurements from fundamental laboratory studies of heat transfer from surface mounted cubes and with numerical results from well established commercial building energy simulation software. Numerical issues, such as temporal and spatial discretization, are addressed, and parametric studies are performed with regard to the effect of external flow Reynolds number and temperature variation in the building envelope, depending on the individual orientation of the external walls with respect to the flow and on the thermal properties of the building materials. Results from the parametric studies performed indicate that the transient three-dimensional calculations provide important information regarding the effect of external flow properties, such as the approaching flow temperature, velocity, and direction on the thermal behavior of the building envelope. In addition, it has been clearly demonstrated that the methodology is also capable of taking into account the complex effects of parameters such as the building material properties. [DOI: 10.1115/1.3139137] Keywords: building thermal simulation, solar heat gains, envelope cooling, CFD

Starting from three-dimensional (3D) continuum mechanics, a simple one-dimensional model aimed at analyzing the whole static behavior of nonhomogeneous curved beams is proposed. The kinematics is described by four one-dimensional (unknown) functions representing radial, tangential, and out-of-plane displacements of the beam axis, which are due to flexures and extension, and the twist of the cross section due to torsion. The flexural and axial displacements fit with the classical Euler-Bernoulli beam theory of straight beams, and nonuniform torsion is also considered. The relevant elastogeometric parameters have been determined, and the system of governing equilibrium equations is obtained by means of the principle of minimum potential energy. Finally, the general theory is illustrated with examples. DOI: 10.1061/(ASCE)0733-9399(2009) 135:7(597) CE Database subject headings: Curved beams; Three-dimensional analysis; Mechanical properties.

We simulate the flow past smooth and rough rigid circular cylinders that are either bare or outfitted with helical strakes. We consider operating conditions that correspond to high Reynolds numbers of [1O.sup.5] and [10.sup.6], and allow for two degree-of-freedom motions such that the structure is allowed to respond to flow-induced cross-flow and in-line forces. The computations are performed using a parallelized Navier--Stokes in-house solver using overset grids. For smooth surface simulations at a Reynolds number of [10.sup.5], we use a Smagorinsky large eddy simulation turbulence model and for the Reynolds number cases of [10.sup.6] we make use of the unsteady Reynolds-averaged Navier--Stokes equations with a two-layer k-epsilon turbulence model. The rough surface modifications of the two-layer k-epsilon turbulence model due to Durbin et al (2001, 'Rough Wall Modification of Two-Layer k-Epsilon,' ASME J. Fluids Eng., 123, pp. 16-21) are implemented to account for surface roughness effects. In all our computations we aim to resolve the boundary layer directly by using adequate grid spacing in the near-wall region. The predicted global flow parameters under different surface conditions are in good agreement with experimental data, and significant vortex-induced vibration suppression is observed when using helically straked cylinders. [DOI: 10.1115/1.3058697]

We present an approach to identify noncooperative individuals at a distance from a sequence of images, using 3-D face models. Most biometric features (such as fingerprints, hand shape, iris, or retinal scans) require cooperative subjects in close proximity to the biometric system. We process images acquired with an ultrahigh-resolution video camera, infer the location of the subjects' head, use this information to crop the region of interest, build a 3-D face model, and use this 3-D model to perform biometric identification. To build the 3-D model, we use an image sequence, as natural head and body motion provides enough viewpoint variation to perform stereomotion for 3-D face reconstruction. We have conducted experiments on a 2-D and 3-D databases collected in our laboratory. First, we found that metric 3-D face models can be used for recognition by using simple scaling method even though there is no exact scale in the 3-D reconstruction. Second, experiments using a commercial 3-D matching engine suggest the feasibility of the proposed approach for recognition against 3-D galleries at a distance (3, 6, and 9 m). Moreover, we show initial 3-D face modeling results on various factors including head motion, outdoor lighting conditions, and glasses. The evaluation results suggest that video data alone, at a distance of 3 to 9 meters, can provide a 3-D face shape that supports successful face recognition. The performance of 3-D--3-D recognition with the currently generated models does not quite match that of 2-D--2-D. We attribute this to the quality of the inferred models, and this suggests a clear path for future research. Index Terms--Biometrics, face recognition, 3-D face modeling.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2008.07.007 Byline: Ursula Buck (a)(b), Silvio Naether (a), Marcel Braun (c), Michael Thali (a) Keywords: Forensic science; Haptic device; Radiological scanning; 3D optical scanning; 3D reconstruction; Virtopsy Abstract: Non-invasive documentation methods such as surface scanning and radiological imaging are gaining in importance in the forensic field. These three-dimensional technologies provide digital 3D data, which are processed and handled in the computer. However, the sense of touch gets lost using the virtual approach. The haptic device enables the use of the sense of touch to handle and feel digital 3D data. The multifunctional application of a haptic device for forensic approaches is evaluated and illustrated in three different cases: the representation of bone fractures of the lower extremities, by traffic accidents, in a non-invasive manner; the comparison of bone injuries with the presumed injury-inflicting instrument; and in a gunshot case, the identification of the gun by the muzzle imprint, and the reconstruction of the holding position of the gun. The 3D models of the bones are generated from the Computed Tomography (CT) images. The 3D models of the exterior injuries, the injury-inflicting tools and the bone injuries, where a higher resolution is necessary, are created by the optical surface scan. The haptic device is used in combination with the software FreeForm Modelling Plusacents for touching the surface of the 3D models to feel the minute injuries and the surface of tools, to reposition displaced bone parts and to compare an injury-causing instrument with an injury. The repositioning of 3D models in a reconstruction is easier, faster and more precisely executed by means of using the sense of touch and with the user-friendly movement in the 3D space. For representation purposes, the fracture lines of bones are coloured. This work demonstrates that the haptic device is a suitable and efficient application in forensic science. The haptic device offers a new way in the handling of digital data in the virtual 3D space. Author Affiliation: (a) University of Bern, Institute of Forensic Medicine, Buehlstrasse 20, 3012 Bern, Switzerland (b) Canton Police Bern, Accident Service, Schermenweg 9, 3001 Bern, Switzerland (c) City Police Zurich, Accident Service, Bahnhofquai 3, 8021 Zurich, Switzerland Article History: Received 20 November 2007; Revised 3 June 2008; Accepted 14 July 2008

Bike power saver (BPS) is a new product that claims to change the angle of pedaling forces and reduce applied power dead range (Chic Sheng Industrial Co., Ltd, Taiwan, China). In order to determine its effectiveness, we quantified how BPS operates through a 3D kinematical study and electromyography (EMG) analysis of leg muscles during pedaling. Ten kinesiology students participated in this study. A 3D motion capture system consisting of nine high-speed cameras (VICON v8i, a capture rate of 120 frames/s) was used to collect the total body and pedal motion with and without BPS at statically determined low, middle and high intensity cycling levels. The short-time test (14 s) was applied to all intensity levels while the long-time test (30min) was applied only to the low wattage level. Wireless EMG was synchronized with the 3D motion capture system to monitor the right and left tibialis anterior, gastrocnemius, quadriceps and hamstring. The results revealed that BPS did not alter hip and knee movement significantly (p>0.05), but it did vary ankle movement. BPS caused a movement change in the pedals, and consequently induced instability in ankle control. The altered pedal movement led to an increase in activity level and presumably also energy expenditure for dominant muscles, resulting in a faster fatigue process. From these data, it is likely that the BPS actually requires more effort than a standard bike. Keywords: 3D motion capture; Joint control; Electromyography; Frequency analysis; Fatigue; Efficiency

A prototype of a 3D dental record for patients can retrieve images and radiographs, give a flexible view of teeth, soft tissue and bone, give access to patient's historical data, and focus on a single tooth. Test users accepted the initial design of the 3D dental record, but further research needs to be conducted before going into practice.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2006.08.024 Byline: Ursula Buck (a)(b), Silvio Naether (a), Marcel Braun (c), Stephan Bolliger (a), Hans Friederich (b), Christian Jackowski (a), Emin Aghayev (a), Andreas Christe (a)(d), Peter Vock (d), Richard Dirnhofer (a), Michael J. Thali (a) Keywords: Virtopsy; Accident reconstruction; Metric wound documentation; Photogrammetry; 3D optical scanning; Forensic radiology Abstract: The examination of traffic accidents is daily routine in forensic medicine. An important question in the analysis of the victims of traffic accidents, for example in collisions between motor vehicles and pedestrians or cyclists, is the situation of the impact. Apart from forensic medical examinations (external examination and autopsy), three-dimensional technologies and methods are gaining importance in forensic investigations. Besides the post-mortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) for the documentation and analysis of internal findings, highly precise 3D surface scanning is employed for the documentation of the external body findings and of injury-inflicting instruments. The correlation of injuries of the body to the injury-inflicting object and the accident mechanism are of great importance. The applied methods include documentation of the external and internal body and the involved vehicles and inflicting tools as well as the analysis of the acquired data. The body surface and the accident vehicles with their damages were digitized by 3D surface scanning. For the internal findings of the body, post-mortem MSCT and MRI were used. The analysis included the processing of the obtained data to 3D models, determination of the driving direction of the vehicle, correlation of injuries to the vehicle damages, geometric determination of the impact situation and evaluation of further findings of the accident. In the following article, the benefits of the 3D documentation and computer-assisted, drawn-to-scale 3D comparisons of the relevant injuries with the damages to the vehicle in the analysis of the course of accidents, especially with regard to the impact situation, are shown on two examined cases. Author Affiliation: (a) University of Bern, Institute of Forensic Medicine, Buehlstrasse 20, 3012 Bern, Switzerland (b) State Police Bern, Accident Service, Schermenweg 9, 3001 Bern, Switzerland (c) Zuerich City Police, Accident Service, 8021 Zuerich, Switzerland (d) University Hospital of Bern, Institute of Diagnostic Radiology, 3010 Bern, Switzerland Article History: Received 20 April 2006; Revised 19 July 2006; Accepted 30 August 2006

Three-dimensional (3-D) microstages driven by electrostatic comb actuators that provide continuous motion along three axes (x, y, and z) were designed and fabricated. Each 3-D microstage consisted of sets of traveling tables, suspension systems, and comb actuators. To convert lateral displacement of the comb actuators to vertical motion, one suspension system incorporated leaf springs inclined to a substrate. To efficiently construct the inclined leaf springs, we devised a fabrication technique that uses deep reactive ion etching. Three-dimensional microstages were then fabricated in a 20-[micro]m-thick device layer on a silicon-on-insulator wafer. The maximum vertical (z) displacement of this 3-D microstage was 2.6 [micro]m, and the maximum lateral displacement (x and y) was more than 6 [micro]m in each direction, achieved by using support suspensions to suppress the interference between the comb actuators. A 3-D microstage was then installed in a commercial atomic force microscope, and a 3-D image of a grating was successfully measured without hysteresis using this 3-D microstage as the scanning device. [1602]

Sheep shearers are known to work in sustained flexed postures and have a high prevalence of low back pain (LBP). As sustained posture and spinal movement asymmetry under substantial loads are known risk factors for back injury our aim was to describe the 3D spinal movement of shearers while working. We hypothesised that thoraco-lumbar and lumbo-sacral movement would be tri-axial, asymmetric, and task specific. Sufficient retro-reflective markers were placed on the trunk of 12 shearers to define thoraco-lumbar and lumbo-sacral 3D motion during three tasks. Thoraco-lumbar movement consistently involved flexion, left lateral flexion, and right rotation. Lumbo-sacral movement consistently involved right lateral flexion in flexion with minimal rotation. Shearers therefore work in sustained spinal flexion where concurrent, asymmetric spinal movements into both lateral flexion and rotation occur. These asymmetric movements combined with repetitive loading may be risk factors leading to the high incidence of LBP in this occupational group. Keywords: Sheep shearing; 3D spinal movement; Low back pain

Garment fit and resultant air volume is a crucial factor in thermal insulation, and yet, it has been difficult to quantify the air volume of clothing microclimate and relate it to the thermal insulation value just using the information on the size of clothing pattern without actual 3D volume measurement in wear condition. As earlier methods for the computation of air volume in clothing microclimate, vacuum over suit and circumference model have been used. However, these methods have inevitable disadvantages in terms of cost or accuracy due to the limitations of measurement equipments. In this paper, the phase-shifting moire topography was introduced as one of the 3D scanning tools to measure the air volume of clothing microclimate quantitatively. The purpose of this research is to adopt a non-contact image scanning technology, phase-shifting moire topography, to ascertain relationship between air volume and insulation value of layered clothing systems in wear situations where the 2D fabric creates new conditions in 3D spaces. The insulation of vests over shirts as a layered clothing system was measured with a thermal manikin in the environmental condition of 20 [degrees]C, 65% RH and air velocity of 0.79 m/s. As the pattern size increased, the insulation of the clothing system was increased. But beyond a certain limit, the insulation started to decrease due to convection and ventilation, which is more apparent when only the vest was worn over the torso of manikin. The relationship between clothing air volume and insulation was difficult to predict with a single vest due to the extreme openings which induced active ventilation. But when the vest was worn over the shirt, the effects of thickness of the fabrics on insulations were less pronounced compared with that of air volume. In conclusion, phase-shifting moire topography was one of the efficient and accurate ways of quantifying air volume and its distribution across the clothing microclimate. It is also noted that air volume becomes more crucial factor in predicting thermal insulation when clothing is layered. Keywords: Air volume; 3D scan; Layered clothing insulation

The three-dimensional Computerized Isometric Strength Measurement System (CISMS) reliably and accurately measures isometric pull and push strengths in workspaces of paraplegic populations while anticipating comparative studies with other populations. The main elements of the system were: an extendable arm, a vertical supporting track, a rotating platform, a force transducer, stability sensors and a computerized data collection interface. The CISMS with minor modification was successfully used to measure isometric push-up and pull-down strengths of paraplegics and isometric push, pull, push-up and pull-down strength in workspaces for seated and standing able-bodied populations. The instrument has satisfied criteria of versatility, safety and comfort, ease of operation, and durability. Results are accurate within 2N for aligned forces. Costing approximately $1,500 (US) including computer, the system is affordable and accurate for aligned isometric strength measurements. Keywords: Isometric strength measurement system; Isometric push, pull, push-up and pull-down strengths; Computerized data collection

In this paper, we present a theory for combining the effects of motion, illumination, 3D structure, albedo, and camera parameters in a sequence of images obtained by a perspective camera. We show that the set of all Lambertian reflectance functions of a moving object, at any position, illuminated by arbitrarily distant light sources, lies "close" to a bilinear subspace consisting of nine illumination variables and six motion variables. This result implies that, given an arbitrary video sequence, it is possible to recover the 3D structure, motion, and illumination conditions simultaneously using the bilinear subspace formulation. The derivation builds upon existing work on linear subspace representations of reflectance by generalizing it to moving objects. Lighting can change slowly or suddenly, locally or globally, and can originate from a combination of point and extended sources. We experimentally compare the results of our theory with ground truth data and also provide results on real data by using video sequences of a 3D face and the entire human body with various combinations of motion and illumination directions. We also show results of our theory in estimating 3D motion and illumination model parameters from a video sequence. Index Terms--Motion, illumination, reflectance, bilinear, 3D structure.

Three-dimensional response of buried pipes under circular surface loading is investigated using the finite-element method. Previous work by Poulos in 1974 is reexamined, considering the longitudinal behavior of pipes under surface loading. Analyses are performed for pipes of varying stiffnesses and embedment depths. When stiff pipes are located close to the ground surface, the burial depth has little impact on the peak deflection. However flexible pipe deflections decrease significantly as embedment depth increases. Not surprisingly, peak moments increase with pipe stiffness and decrease as the pipes become more remote from the ground surface. The comparison of the new results with those of Poulos indicates that his Mindlin solution calculations are somewhat conservative relative to the finite-element solutions for deeply buried pipes, but unconservative at shallow burial. DOI: 10.1061/(ASCE) 1090-0241(2007)133:2(219) CE Database subject headings: Three-dimensional analysis; Buried pipes; Finite element method; Loads.

Piezoceramic transducers (PZTs) are extensively used in vibration and noise control, and damage detection of various engineering structures. In the last decade, its application has been extended to include their interactions with the host structure in electromechanical impedance models. The interaction between the host structure and PZT is governed by both the extensional and longitudinal vibrations of the transducer. However, the interaction models developed in the last decade consider only the one-dimension or two-dimension extensional actuations, ignoring the longitudinal actuations. This study examines the three-dimensional (3D) interaction of a transducer with the host structure, considering both the extensional and the longitudinal actuations of the transducer. It does not impose any restriction on the shape, size, and electrical properties of the PZT and thus contains additional features over the existing PZT-structure interaction models. This paper is Part I of a two-part paper, which presents a new 'directional sum' numerical-analytical admittance formulation with experimental verification. Part II of this paper will elaborate on the damage analysis and characterization of PZT properties for the new 3D model. DOI: 10.1061/(ASCE)0893-1321(2007)20:1(53) CE Database subject headings: Structural reliability; Monitoring; Three-dimensional models; Damage.

This paper presents the results of 150 finite-element simulations conducted to define the effects of excavation geometry, i.e., length, width, and depth of excavation, wall system stiffness, and factor of safety against basal heave on the three-dimensional ground movements caused by excavation through clays. The results of the analyses are represented by the plane strain ratio (PSR), defined as the maximum movement in the center of an excavation wall computed by three-dimensional analyses normalized by that computed by a plane strain simulation. A simple equation for PSR is presented based on excavation geometry, wall system stiffness, and factor of safety against basal heave. This PSR equation reasonably represents trends in results of the 150 simulations as well as those simulations reported in literature. When the excavated length normalized by the excavated depth of an excavation wall is greater than 6, results of plane strain simulations yield the same displacements in the center of that wall as those computed by a three-dimensional simulation. DOI: 10.1061/(ASCE)1090-0241(2007)133:1(30) CE Database subject headings: Three-dimensional analysis; Excavation; Clays; Geometry; Stiffness.

The identification of a three dimensional constitutive model is useful for describing the complex mechanical behavior of a nonlinear and anisotropic biological tissue such as the esophagus. The inflation tests at the fixed axial extension of 1, 1.125, and 1.25 were conducted on the muscle and mucosa layer of a porcine esophagus separately and the pressure-radius-axial force was recorded. The experimental data were fitted with the constitutive model to obtain the structure-related parameters, including the collagen amount and fiber orientation. Results showed that a bilinear strain energy function (SEF) with four parameters could fit the inflation data at an individual extension very well while a six-parameter model had to be used to capture the inflation behaviors at all three extensions simultaneously. It was found that the collagen distribution was axial preferred in both layers and the mucosa contained more collagen, which were in agreement with the findings through a pair of uniaxial tensile test in our previous study. The model was expected to be used for the prediction of stress distribution within the esophageal wall under the physiological state and provide some useful information in the clinical studies of the esophageal diseases. [DOI: 10.1115/1.2354206] Keywords: strain energy function (SEF), inflation, constitutive model, collagen

This paper describes the design, fabrication, and force analysis of a pneumatically driven microcage. Pneumatic actuation, suitable to function in a wide range of environments, is especially useful for operation in a small liquid space. The capture of single motile microbes (Volvox and Stentor ~ 400 [micro]m) in aqueous environments is demonstrated with the microcage. The setup for the capture experiment includes a visualization scheme, a robotic micropositioner, and an electropneumatic control system that facilitates the underwater tracking of the moving microbes and the operation of the microcage for subsequent capture. Index Terms--Microelectromechanical systems (MEMS), pneumatic actuation, residual stress, three-dimensional (3-D) structure.

Blood perfusion in organs has been shown to be heterogeneous in a number of cases. At the same time, a number of models of vascular structure and flow have been proposed that also generate heterogeneous perfusion. Although a relationship between local perfusion and vascular structure has to exist, no model has yet been validated as an accurate description of this relationship. A study of perfusion and three-dimensional (3D) arterial structure in individual rat kidneys is presented, which allows comparison between local measurements of perfusion and model-based predictions. High-resolution computed tomography is used to obtain images of both deposited microspheres and of an arterial cast in the same organ. Microsphere deposition is used as an estimate of local perfusion. A 3D cylindrical pipe model of the arterial tree is generated based on an image of the arterial cast. Results of a flow model are compared with local microsphere deposition. High correlation ([r.sup.2] > 0.94) was observed between measured and modeled flows through the vascular tree segments. However, the relative dispersion of the microsphere perfusion measurement was two- to threefold higher than perfusion heterogeneity calculated in the flow model. Also, there was no correlation in the residual deviations between the methods. This study illustrates the importance of comparing models of local perfusion with in vivo measurements of perfusion in the same biologically realistic vascular tree. perfusion heterogeneity; three-dimensional imaging; microcomputed tomography; casting; rat kidney; blood flow