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The research of intelligent simulation of virtual human in virtual environment is an interesting direction in the domain of AI after the research of virtual human's behavior simulation. This paper presents a new research platform named AIPlayer in order to promote this work. Virtual environment is come close to the real world. Some characteristic in virtual environment can realistically represent the real world, at the same time it can provide some advantages to science research . This virtual environment may be MMORPG or virtual reality. The motive of the research is to simulate a virtual human who can autonomous live in the virtual environment. We named this research as intelligent simulation of virtual human in virtual environment. First, this paper argues the significance of this research in theory and application, then analyses the demand of the AIPlayer, the characteristic of its living environment, the aim of AIPlayer and some correlative research domain may be involved, then it describes the architecture of AIPlayer and the core of AIPlayer: BSOAA( based smart object agent architecture), at last a prototype of AIPlayer in virtual environment is introduced. [ABSTRACT FROM AUTHOR]

This paper presents the background and history of the virtual human SantosTMdeveloped by the Virtual Soldier Research (VSR) Program at The University of Iowa. The early virtual human environment was called MiraTM. This 15-degree-of-freedom (DOF) upper-body model with posture and motion prediction was funded by John Deere Inc. and US Army TACOM Automotive Research Center. In 2003 US Army TACOM began funding VSR to develop a new generation of virtual humans called Santos (109 DOFs), which was to be another generation of Mira. Later on, Caterpillar Inc., Honda R&D North Americas, Natick Soldier System Center, and USCAR (GM, Ford, and Chrysler) joined the VSR partnership. The objective is to develop anew generation of digital humans comprising realistic human models including anatomy, biomechanics, physiology, and intelligence in real time, and to test digital mockups of products and systems before they are built, thus reducing the significant costs and time associated with making prototypes. The philosophy is based on a novel optimization-based approach for empowering these digital humans to perform, un-aided, in a physics-based world. The research thrusts include the following areas: (1) predictive dynamics, (2) modeling of cloth, (3) hand model, (4) intuitive interface, (5) motion capture, (6) muscle and physiology modeling, (7) posture and motion prediction, (8) spine modeling, and (9) real-time simulation and virtual reality (VR). Currently, the capabilities of Santos include whole-body posture prediction, advanced inverse kinematics, reach envelope analysis, workspace zone differentiation, muscle force and stress analysis, muscle fatigue prediction, simulation of walking and running, dynamic motion prediction, physiologic assessment, a user-friendly interface, a hand model and grasping capability, clothing modeling, thermo discomfort assessment, muscle wrapping and sliding, whole-body vibration analysis, and collision avoidance. [ABSTRACT FROM AUTHOR]

Chinese culture and consumer patterns are dramatically different from those in the US and Europe. That greatly impacts the types of products that are relevant to the Chinese market, the product development life cycle and methods by which these products are defined and developed for information and communication technologies (ICT). To address those unique differences, the User Centered Design (UCD) research team at Intel China has developed and refined techniques for involving engineering staff in the early stages of product design, namely user research and experience design. This early involvement has many advantages and improves the overall effectiveness of the product development team. This article describes the role of the engineers in the early phases of the user centered process, and the learnings and challenges that come from this approach. Real-world case studies are used to illustrate the methodologies. [ABSTRACT FROM AUTHOR]

Somatosensory function declines with age, and such changes have been associated with diminished motor performance. Noise input can enhance sensory and motor function.We tested the effects of the vibrating stimulation applied at the feet on balance control of 6 healthy elderly and 8 young volunteers. Balance performance was characterized using a FASTRAK System. We calculated four traditional measures of postural sway parameters and five stabilogram-diffusion analysis variables.Among the 14 participants, application of noise resulted in a reduction of seven of nine sway parameters in young participants and eight of nine sway variables in elderly participants. The results suggested that the imperceptible noise, when applied to the feet, could enhance the balance performance of healthy older adults. Therefore, using the noise-based devices may be an effective way to improve the balance control of elderly people. [ABSTRACT FROM AUTHOR]

According to ergonomics factors referred by airplane design department and corresponding standards, structure and function of ergonomics evaluation system of 3D cockpit was designed. Digital human model, based on anthropometry database, comprises 66 segments, 65 joints and 131 degree of freedom. The ergonomics design of man-machine interface can be evaluated in terms of vision, reach and working posture comfort analysis methods and evaluation rules. Interior and exterior visual field of pilot can be achieved with the aid of vision analysis. The comfort of working posture and joints motion can be assessed by reference to joint angles for any selected posture. The details regarding system implementation with technology of OpenGL are discussed at last. The system can be computer-aided tool for airplane designer considering its convenience in using excellent model data interface with other 3D software. [ABSTRACT FROM AUTHOR]

This paper presents a novel cloth-body collision detection method by using the generalized cross-sectional contour technique, which has two main steps. During preprocessing step, the so-called skin hierarchical structure (Skin-H) of the body is constructed by using the improved generalized cross-sectional contour technique, which doesn't need to be updated in subsequent step. During runtime step, the cloth vertices are projected onto Skin-H structure efficiently, and then the exact collision detection can be done by a ray-triangle test technique at the lowest level of the structure. The simulation result demonstrates that the proposed method has some advantages in algorithm's efficiency, accuracy as well as practicability. [ABSTRACT FROM AUTHOR]

With the increasing of traffic complexity, traffic simulation becomes an important approach to deal with the complicated traffic problems; meanwhile, system modeling plays a more and more important role in the simulation systems. Cellular automata provide a simple discrete deterministic mathematical model for physical, biological, and computational systems and are shown to be capable of complicated behavior and generate complex and random patterns, which are very suitable for the description of complicate traffic environment [7]. A simulation model based on agent technology, HLA/RTI technology and expanded cellular automaton is presented in this paper. The simulation model makes the platform expandable and flexible, at the same time, it can provide high-capable computing resources to solve the complex traffic issues. In the traffic entity model aspects, the expanded cellular automata and agent technology were adopted to model the behaviors of passengers, vehicles, traffic signal lights and so on. The optimal scheme for evacuation of traffic disaster, superintendence of large scale activities and design of traffic environment will be obtained through the simulation model. [ABSTRACT FROM AUTHOR]

The development of the experimental Remote Tower Operation Human Machine Interface and the new Remote-Controller work position is supported by a cognitive work and task analysis (CWA) of the presently existing work environment and decision processes at airport Leipzig. This paper presents a formal approach for the description of the whole Human Machine System. It is shown how the results of a cognitive work analysis on a medium size airport are transferred into a formal executable human machine model for simulating the controllers work processes in relation to the airport processes. The model is implemented with Colored Petri Nets. The mathematical basis of Petri Nets allows a formal analysis of whole systems. Critical system states and inconsistencies in the human machine system are identified through comparison of knowledge states of the controllers with process states of the airport system by using State Space analysis. The represented formal work process model provides a valuable support for the communication between domain experts and system developers. [ABSTRACT FROM AUTHOR]

Recent collaborative efforts between Greenville Technical College's Aviation Maintenance Technology (Greenville, South Carolina, USA) training facility and Clemson University (Clemson, South Carolina, USA) have lead to significant improvements in Aviation Maintenance Technician training through the use of advanced computer technology. Such applications included: 2.5D and 3D virtual environments of a large-bodied aircraft cargobay with interaction modalities ranging from fully immersive (using a head-mounted display and 6 degrees-of-freedom mouse) to semi-immersive (using a spatially-tracked suspended, touch-sensitive window display) to non-immersive (using a basic desktop computer and mouse); and 3D virtual environments of turbine engine blades where nondestructive inspection methods (e.g. borescoping) could be practiced. This paper discusses the integration of these technologies into an existing educational curriculum and provides insight as to how such programs might be implemented and evaluated. [ABSTRACT FROM AUTHOR]

Early integration of ergonomics in the vehicle design process requires appropriate CAD tools. 15 years ago, the German car industry developed a new, three-dimensional tool for computer-aided ergonomics and occupant packaging, called RAMSIS. Its goal was to overcome the limitations of two-dimensional human templates, as well as to provide methods for predicting driver postures and comfort. The core of RAMSIS is a highly accurate three-dimensional human model that can be made to simulate occupants with a large variety of body dimensions and based on anthropometry databases from around the world. Extensive research was conducted on driver postures and comfort, which resulted in a probability-based posture prediction model. No subjective manikin manipulation by the user is necessary, so that fast, realistic and consistent analysis results are ensured at all times. An assessment of comfort allows designers to optimize packages with respect to driver comfort early in the design process. RAMSIS offers a number of other analysis tools, for example for vision, reach, force and seat belt studies. Over the years, new research projects have resulted in more sophisticated RAMSIS functions, such as a force-based posture and comfort prediction model, seat belt certification, compatibility with full body laser scanners, simulation of the interaction between seat and occupant and simulation of ingress and egress. [ABSTRACT FROM AUTHOR]

Electronics packaging plays a crucial role in the manufacturing of advanced microelectronics, with an increased interest in technology that produces greater power functionality in smaller spaces. The recent advances in this field have led to advanced manufacturing techniques, with the insertion of components in the micro- and nano-scales. In particular, the microlithography panel printer uses photolithography to create fine image patterns through reticles on substrate boards. The need for advanced features, updated software skills, and the high cost of human error places an increasing requirement for more efficient operator training at a reduced financial investment. Therefore, this research demonstrates the usefulness of virtual reality in modeling the microlithography machine using high fidelity simulations for training purposes. The development process and the structure of the training simulator is presented, with an outline of its effectiveness in supporting training needs, and a description of its reliability assessment through validation and testing. [ABSTRACT FROM AUTHOR]

This paper focuses on validating the performance of virtual interactive design (VID) environment with dynamic ergonomics analysis. Previous studies have only validated VID for posture-based static ergonomics analysis, and applied the methodology on several studies. While since dynamic information is important for ergonomics analysis, this study will investigate the performance of VID environment for ergonomics analysis considering dynamic information such as velocity, which uses motion instead of posture as analysis target. [ABSTRACT FROM AUTHOR]

Human-populated VR models have been employed by many researchers to evaluate workspace occupational health and safety (OHS) problems. Previous researches in VR-based ergonomic evaluation have taken a model-based, quantitative approach where human posture data are extracted from virtual space and sent to ergonomic models to calculate numeric results. Such model-based approach requires the VR model to be integrated with complex human models and ergonomic evaluation models. Construction of the virtual workspace thus becomes complicated and difficult, which often stops industrial adoption of the VR technology in ergonomic evaluation. To address this problem, this paper presents an easy-to-construct human-populated VR model to support visualization-based, qualitative workspace OHS evaluation. Details of the workspace layout design and the operation procedure design, and the dynamic VRML modeling to support the workspace design are discussed. Based on the proposed method, a human-populated virtual workspace is implemented to evaluate OHS problem associated with the design of a ship operation room. [ABSTRACT FROM AUTHOR]

As the foundation of user-system interaction in virtual environments, collision detection is a time-consuming process and few real-time interactive algorithms for general objects developed. Most of the existing methods aim for reducing the computation time for some special cases. Collision detection algorithms developed are either not fast enough for practical applications or restricted to a class of specific model. In fact, a general analysis of the performance of collision detection algorithms is extremely difficult because performance is situation specific. The motivation of this work is to satisfy the real-time interaction and high precision requirements of a Virtual Environment (VE) for applications such as virtual design, virtual assembly, virtual training for manufacturing operations and maintenance. [ABSTRACT FROM AUTHOR]

Inspection quality is dependent on the ability of inspectors to weed out defective items. When inspection is visual in nature, humans play a critical role in ensuring inspection quality with training identified as the primary intervention strategy for improving inspection performance. However, for this strategy to be successful, inspectors must be provided with the needed tools to enhance their inspection skills. In this article we outline efforts pursued at Clemson University, focusing on the development of computer-based training systems for inspection training and discuss the results of some of the research briefly. [ABSTRACT FROM AUTHOR]

This paper studies the use of Virtual Reality and Human Simulation for the ergonomic evaluation of manual assembly processes. A virtual environment has been developed to represent the actual workspace where the assembly task took place. Into the virtual workspace, a digital human /mannequin was imported and programmed to simulate the task, in the same manner as it would be done by the actual worker. Based on the posture-based ergonomics analysis, each posture of the digital human has been "translated" into comfort scores, resulting in conclusions, related to the ergonomic efficiency of the process and in the design of the workstation. The conclusions that have been reached identify the critical points, during the assembly task, and lead to the necessary re-design actions in order for the worker's fatigue as well as the task's execution time to be reduced. A real-life assembly task of a commercial refrigerator has been implemented in order for the capabilities of the proposed process design evaluation method to be demonstrated. [ABSTRACT FROM AUTHOR]

The aim of the present work was to gather data concerning the measurements and the shape of individuals' feet of Italians, to design more ergonomic shoe lasts. The unloaded feet of a sample of 316 participants of Italian ethnicity of 20 different towns located in northern, central, and southern Italy and the Italian islands were digitalized. Results showed significant differences by gender, age, and geographical area. The sample's degree of awareness concerning some of their own foot characteristics and interaction with footwear were also investigated. These findings will be used to design footwear that can provide a good fit for the feet of Italians and, consequently, a greater degree of comfort. [ABSTRACT FROM AUTHOR]

The EVA spacesuit glove is one of the key components which can assure astronauts to achieve EVA tasks in security. Astronauts are subjected to the influence of low temperature when they are performing tasks outside the spaceship. To establish the standard of the ergonomics of the temperature of the glove work is very important. This paper studies the influence of low temperature on the ergonomics of the glove work when the skin surface temperature of the middle fingertip is at normal temperature, 15.60C and 100C respectively, in which the strength, fatigue, sensibility and flexibility are made as evaluation targets. The experiment indicates: the influence on the ergonomics of glove is not obvious when the temperature is controlled at 15.60C. Therefore the temperature of the middle fingertip skin should be controlled above 15.60C in glove design; the influence to the ergonomics of glove is relatively obvious when the temperature is about 100C. The influence on sensibility is the most obvious, and then the influence on fatigue, strength and flexibility is in descending order. The temperature standards of EVA spacesuit glove have practical meaning to design EVA spacesuit. [ABSTRACT FROM AUTHOR]

The study of pilot perception has evolved from examining simple tasks executed in reduced laboratory conditions to the examination of complex, real-world behaviors. A test-bed for evaluating models of pilot behavior in which a set of infrared video-based eyetrackers to monitor subjects' eye movements while they perform a range of complex tasks such as driving, and manual tasks requiring careful eye-hand coordination was developed. The real cockpit platform is provided to subjects as they pilot in a virtual scene; a dual-haptic interface consisting of two touch-screen display devices and a shift allows free control within the cockpit. [ABSTRACT FROM AUTHOR]

This paper emphasized on how to construct one kind of assessment system based on the standards and specifications for cockpit ergonomic synthesis assessment, and the knowledge of the aviation experts and the experienced pilots. It analyzed the necessity of developing the assessment system, and then presented the basic principal and the function demand of the assessment system. In addition, the key technologies for developing this assessment system were discussed in detail utilizing Visual FoxPro 6.0. This assessment system transforms the assessment model and process into the computer program by the mathematical model, enables the assessment process truly to be operational, and also can reduce the assessment cycle. [ABSTRACT FROM AUTHOR]

This paper discusses the impact of human interaction with biometric devices and its relationship to biometric performance. The authors propose a model outlining the Human-Biometric Sensor Interaction and discuss its necessity through case studies in fingerprint recognition, hand geometry, and dynamic signature verification to further understand the human-sensor interaction issues and underlying problems that they present to the biometric system. Human factors, human-computer interaction and digital human modeling are considered in the context of current and future biometric research and development. [ABSTRACT FROM AUTHOR]

The relationship between the properties of flexible polyurethane foam composing seat cushions for standard cars and the riding discomfort evaluated by subjects who sat on the seat were investigated. The properties of five kinds of polyurethane foam were measured using the DMA to define dynamical properties. Riding discomfort was subjectively evaluated by 17 subjects at four frequencies, and the correlation coefficients between the material properties and riding discomfort were analyzed. The results suggested that there were two relationships between material properties and riding discomfort, and that these relationships strongly relied on frequency. Furthermore, a digital human model was created to confirm the influence of frequency on these relationships, which suggested that the relationships affected sensitivity by the change in the vibration mode of the human body-seat vibration system. [ABSTRACT FROM AUTHOR]

Recently, ergonomic design is a key issue in the warship design. Ergonomic ship design aims to improve the safety and convenience of crew and passengers. In this paper, as a basis of analyzing and evaluating ergonomic design criteria and evaluation methods for a warship, existing military design guidelines and navy criteria in the fields of ergonomics were surveyed. Also, the methodology including an ergonomic human model is introduced. Finally, it is shown that the ergonomics evaluation of a design can be performed at the early stage of warship design using Navy Ergonomic Human Model based on Delmia's ERGO. [ABSTRACT FROM AUTHOR]

We propose an innovative 3D wig designing system which would replace the traditional manual method. The customer's head is scanned by a 3D head scanner and the whole design process is computerized. After sending the design data to the wig-making factory through the internet, the data are reproduced by an NC milling machine to make a wig pattern. To realize our integrated 3D wig designing system, various CAD technologies are implemented: 3D scanning, triangular mesh generation, texture mapping, mesh smoothing, mesh splitting, mesh offsetting, 3D sketch using NURBS curve, tool-path generation, etc. [ABSTRACT FROM AUTHOR]

In this article, we study how users determine the way to operate cylindrical interfaces (lever, switch, etc.) according to their dimensions, shape, and the user's hand dimensions. With a target of avoiding control failure, it is important to estimate user's intuitive operation of a given interface from design. Eight subjects were observed operating different cylinders with various height and diameter. The boundary between the tilting operation and other operations was found to be related to an aspect ratio; the ratio of the diameter to the height. The boundary between the sliding operation and rests was determined by a comparison of hand width with cylinder height. The boundary between the pushing and rotating operations was thought to be related to the length of the distal phalanxes of the fingers. [ABSTRACT FROM AUTHOR]

The objective of this investigation is to measure and document any significant difference in motion performance between the partial pressure suit (PPS) and the common clothing (CC), and therefore to explore the ergonomics evaluation indexes and appraisal methods of protective clothing (PC). This paper presents the results of three human mechanics tests and two operational performance tests conducted on nine male subjects which made possible the comparative evaluation under these two different situations. The human mechanics tests included a range of motion (ROM) test, a grip strength test, and a torque test while the operational performance tests included a target-aiming test and a screwing nuts test. Significant difference was found between the two suits in the ROM test, the grip strength test as well as the target-aiming test. This study demonstrates that motion performances vary significantly between the two suits and ROM together with grip strength can serve as ergonomics evaluation indexes of PC. [ABSTRACT FROM AUTHOR]

The objective of this research project was to improve manual work tasks and workplace design with a new digital human model based design method. The idea of the method was to make the design and analyze of work and workplaces easy for floor level development case. It also should to be exploitable in the context of participatory design approach. The developed method was implemented on a production design simulation platform. It was designed to be used in design of human factors, performance and functionality of a production concurrently. The implemented tool includes basic human motions which exploit real human motion data, effective work design features to easily generate variational solutions, embedded ergonomic analyses and checklists to help analyzing different work environment solutions, and to document the design outcome. Four industrial case studies were completed with the tool. The results show that the tool is feasible for individual and group design work, and has positive impacts on the design process and on the way how individuals can influence on her or his future work in production system. [ABSTRACT FROM AUTHOR]

The vehicle ingress and egress are important issues for the automotive industry, both for minimizing assembly work load and for maximizing end-users' comfort. Digital human modeling tools are used for evaluating and visualizing these issues. The assembler and end-user are more or less performing the very same entering task if the vehicles have identical geometrical prerequisites. The major difference is the vehicle speed; an assembler is entering a vehicle slightly moving forward on the assembly line with a speed of 5 meter/minute whereas the end user's vehicle is standing still. The human motion when entering a car is a complex biomechanical process, which affects many different body parts. Car ingress techniques, such as flopper, swiveler, and glider vary among humans; for which humans' agility may be one affecting factor. Agility is affected by joint diseases, which is more frequent among older people. There are several studies regarding ingress motion patterns[1,2], but studies on the differences in car ingress motion between car assemblers and end-users, or older and younger people are rare. Thus the purpose of the present study was to compare the ingress motion between younger versus older persons, and assemblers versus end-users. [ABSTRACT FROM AUTHOR]

The purpose of this research is to develop a system for computer-aided ergonomic assessment of products without real subjects and physical mockups by integrating a digital hand model with a product model. In previous work, we developed functions of a semi-automatic grasp planning for the digital hand and of quantitatively evaluating the grasp stability of the product based on the force-closure and the grasp quality in our system. We also confirmed the validity of the results of these functions by comparing them with the real grasp postures. In this paper, we propose a new function of evaluating "ease of grasping (EOG)" for the grasp posture based on EOG-map constructed from principal component analysis for finger joint angles in real subjects' grasps. [ABSTRACT FROM AUTHOR]

This paper represents current and probable applications of Digital Human Modeling (DHM) in different industries. Three real-world challenges, Cummins Inc. (New Product Launches), NASA (Ground Operations), Purdue University (DHM in Curriculum), are investigated for current/probable benefits of DHM. Direct contacts with company representatives and academic faculty were established to understand the current challenges and probable demands of tasks/operations in industry where DHM tools can be utilized. Dassault Systemes' CATIA V5 PLM solution package and UGS Tecnomatix JACK DHM software was utilized to offer a resolution for industrial (Cummins Inc. and NASA) challenges and a software manual (JACK) is developed to enhance the engineering curriculum at Purdue University. The results indicated that DHM tools have potential to improve the product development challenges and provides control of the entire process of designing and analyzing a product before it's ever launched. DHM in engineering curriculum would also increase the integration/adaptation of DHM tools in industry. [ABSTRACT FROM AUTHOR]

In order to assess the seating and riding comfort design of a vehicle seat in an objective manner, finite element occupant models with anatomically precise features have been developed. The human body models are incorporated into Pam-Comfort, a tool for automotive seat design and analysis, as parts of occupant surrogates that also include HPM I and II. In this paper, the detailed process of FE human body modeling including an effort on the implementation of new anthropometry will be introduced. The validation of some features of human body models in seating and riding comfort simulation against human experiments will be also presented. [ABSTRACT FROM AUTHOR]

The purposes of this study are to manufacture a flat pattern according to silhouettes through the Surface Flattening process of a triangle by the grid method, and to verify the result to present the method for manufacturing patterns according to designs. Based on the data measured by Size Korea, this study modeled a representative figure ranging from 18 year-old to 24 year-old female, modified the modeled body shapes to a semi-fit silhouette and loose-fit silhouette and did the surface flattening development. We manufactured patterns according to silhouettes and analyzed the area differences between 3D-piece and flat patterns and the deviation between a muslin scan data manufactured by a flat pattern and modeled data. The result of the surface flattening development by the method can be utilized for manufacturing garment patterns by converting a 3D scan data into 2D pattern and proved to be excellent at piece re-creating because the result did not show a big difference from a modeled silhouette. [ABSTRACT FROM AUTHOR]

Based on Neural Mechanism theory of short-term memory, a predigested model was established. It demonstrated learning, establishment and strengthening process concerning with the motor pattern domination of high-level nerve center system. According to the model three feedback loops and their dialectic correlation were synthetically analyzed during rowing athletes studied the technique in training. The analyzed results provided the technical requests and measuring parameters of the system, then, a visual feedback system for rowing was designed and developed. This system has been primarily used in the national rowing team. [ABSTRACT FROM AUTHOR]

Until now DHMs are especially used to design the dimensions of products and production assembly according to anthropometric demands. Recently DHMs are additionally equipped with strengths simulation so that also the dimensioning of reaction forces is possible. First steps are done to describe and evaluate the contact between human body and environment. Some examples will be shown. However in this area further important steps are necessary. Especially the self paced calculation of posture depending on this contact is to be realized. Some proposals exist for the contact of seat and body. Also first basic research is done in order to simulate motion behavior. Especially the detection of "leading body elements" as basic idea for this simulation can be seen as an initial step to generate modeling of cognitive human properties. However, in order to realize it the simulation of the properties of sense organs is necessary. Certain properties of the eyes can be simulated rather simple. Meanwhile some experience exits to understand the glance behavior depending on specific tasks (e.g. car driving). That can serve as basic for input to cognitive models. The output of these can be the track in space of the leading body element. On the other hand sensor organs properties in the field of hearing and climate are possible. In both cases the more difficult problem is to simulate the properties of the environment. General application field of these future development is the computer aided ergonomic design of workplaces in production lines and of products especially vehicles already in the definition and development phase. In this connection is to be considered that in future especially the design of information flow in these areas becomes dominant. An example is the growing development of assistance systems in cars. The application of DHMs will allow achieving the connection between information design and the necessary geometric design of the equipment. [ABSTRACT FROM AUTHOR]

A patient-specific surface model of the proximal femur plays an important role in planning and supporting various computer-assisted surgical procedures including total hip replacement, hip resurfacing, and osteotomy of the proximal femur. The common approach to derive 3D models of the proximal femur is to use imaging techniques such as computed tomography (CT) or magnetic resonance imaging (MRI). However, the high logistic effort, the extra radiation (CT-imaging), and the large quantity of data to be acquired and processed make them less functional. In this paper, we present an integrated approach using a multi-level point distribution model (ML-PDM) to reconstruct a patient-specific model of the proximal femur from intra-operatively available sparse data. Results of experiments performed on dry cadaveric bones using dozens of 3D points are presented, as well as experiments using a limited number of 2D X-ray images, which demonstrate promising accuracy of the present approach. [ABSTRACT FROM AUTHOR]

In contrast to the previous studies that have dealt with phenomenon of coherence resonance induced by external noise in excitable neuron model, in this paper the mechanism of bifurcation-dependent coherence resonance (CR) of excitable neuron model is investigated by researching the random transitions of system motion between attractors in the two sides of bifurcation point. The results of research show: For two excitable neuron model, FHN neuron model and HR neuron model, There exist different attractors in two sides of the two excitable neuron model Hopf bifurcation point, at the presence of internal or external noise the system motion may transit between attractors in two sides of bifurcation point; mechanism of bifurcation-dependent CR of excitable neuron model is related to this kind of random transitions, the frequency of transitions tend towards a certain frequency for a certain optimal noise intensity, and the signal-noise-ratio of system response evaluated at this certain frequency is maximal at the optimal noise intensity, CR occurs. [ABSTRACT FROM AUTHOR]

This paper describes a new virtual dynamic dentomaxillofacial system. Mechanical articulators have been used to reproduce mandibular movements and analyze occlusal contacts. With the help of VR and visualization technologies, virtual articulator systems can provide dynamic simulation and quantitative information visualization, enhance the functionality, and extend the system to additional application areas. We integrate mandibular movement simulation, occlusal analysis and TMJ analysis into our system, and design new algorithms to improve the results of analysis. This system is helpful to the education, the research, and the clinic in dentistry. An evaluation is conducted to prove the functionality and usability of the system. [ABSTRACT FROM AUTHOR]

Epilepsy is the most common neurological disorder in the world, second only to stroke. There are nearly 15 million patients suffer from refractory epilepsy, with no available therapy. Although most seizures are not life threatening, they are an unpredictable source of annoyance and embarrassment, which will result in unconfident and fear. Prediction of epileptic seizures has a profound effect in understanding the mechanism of seizure, improving the rehabilitation possibilities and thereby the quality of life for epilepsy patients. A seizure prediction system can help refractory patients rehabilitate psychologically. In this paper, we introduce an epilepsy seizure prediction algorithm from scalp EEG based on morphological filter and Kolmogorov complexity. Firstly, a complex filter is constructed to remove the artifacts in scalp EEG, in which a morphological filter with optimized structure elements is proposed to eliminate the ocular artifact. Then, the improved Kolmogorov complexity is applied to describe the non-linear dynamic transition of brains. Results show that only the Kolmogorov complexity of electrodes near the epileptogenic focus reduces significantly before seizures. Through the analysis of 7 long-term scalp EEG recordings from 5 epilepsy patients, the average prediction time is 8.5 minutes, the mean sensitivity is 74.0% and specificity is 33.6%. [ABSTRACT FROM AUTHOR]

In this paper, we aim to classify surface electromyography (sEMG) by using Attribute Bagging-Radial Basis Function (AB-RBF) hybrid classifier. Eight normally-limbed individuals were recruited to participate in the experiments. Each subject was instructed to perform six kinds of finger movements and each movement was repeated 50 times. Features were extracted using wavelet transform and used to train the RBF classifier and the AB-RBF hybrid classifier. The experiment results showed that AB-RBF hybrid classifier achieved higher discrimination accuracy and stability than single RBF classifier. It proves that integrating classifiers using random feature subsets is an effective method to improve the performance of the pattern recognition system. [ABSTRACT FROM AUTHOR]

The newly developed method for medical noisy data segmentation for the purpose of presentation and supporting the diagnostics is introduced. It also allows for morphometry and visualization of medical multimodal and dynamical data. A general mathematical framework is presented and characterized together with numerous applications. As this tool is designed to support human-computer interaction by means of involving the sense of sight, and suspected to be worthy in the virtual environment sensitive to the sense of touch, the discussion is supported with numerous examples of visualizations and multimodal and multidimensional applications of proposed method. [ABSTRACT FROM AUTHOR]

Since the 2001 Institute of Medicine Report which estimated that 44,000 to 98,000 patients die each year as a result of healthcare error. This report in effect launched a global patient safety movement, with many proposed regulatory, research and administrative solutions. Patient safety areas of focus such as work complexity, teamwork and communication, technology, and evidence based practice provide a basis for understanding healthcare error. Reliability concepts are the goal of healthcare organizations; and applications such as simulation theory provide means to achieve this status. The translation of research into practice is the foundation of organizational patient safety. Understanding and awareness of patient safety issues has increased; however, significant work to improve patient care outcomes remains. [ABSTRACT FROM AUTHOR]

Recent research trends focus on how multiscale biomedical information can be modeled and transformed into knowledge, in order to lead to a less interfering but also more individualized diagnosis and therapy. In order to assess the clinical importance of models of human pathology (e.g. cancer), it is necessary to validate them with prior and post treatment clinical data which in turn requires the determination of the tumor size and shape with high resolution, accuracy and precision, as well as structural and physiological information. This paper discusses some of the most important image analysis challenges in order to define an optimal method for extracting more accurate and precise anatomical and functional information related to the underlying pathology, which can be used for initializing and validating models of pathophysiology as well as simulations/predictions of the response to therapeutical regimes. [ABSTRACT FROM AUTHOR]

Computer Simulations of cardiac wave propagation may be used as a tool towards understanding the mechanisms of cardiac conduction, the nature of various heart diseases, as well as the effect of drugs in cardiac function. Such simulations depend on the ionuc current model adopted, and various such models have been proposed. The exact propagation wavefront thus depends on the ionic model and the tissue properties, being homogeneous or heterogeneous. The latter case, which corresponds to infracted cardiac tissue, is the focus in this work. The ionic current properties and the sodium kinetics on a two-dimensional grid where wavefront rotations around barriers at bifurcation sites take place, are examined in detail and differences in propagation characteristics elicited by using fast or slow fast inward current kinetics such as can be found in the Beeler-Reuter, Luo-Rudy and Ebihara-Johnson models are elaborated. [ABSTRACT FROM AUTHOR]

We describe the latest development of a computer-based virtual reality environment for training interventional neuroradiology procedures. The system, NeuroCath (Neuroradiology Catheterization Simulator), includes extraction and construction of a vascular model from different imaging modalities that represents the anatomy of patient in a computationally efficient manner, and a finite element method (FEM) based physical model that simulates the interaction between the devices and neuro-vasculature. A realistic visual interface with multiple, synchronized windows and plenty of video control functions are developed. The latest version is also equipped with haptic feedback module that gives the sense of touch in real-time, and customizable vascular model so that trainer can understand the importance of vascular variations and practice. According to the validation in several clinical centers, 70%-75% of training features have been realized which makes the system well suitable for training of interventional neuroradiologists. [ABSTRACT FROM AUTHOR]

With growth of sequenced genome, a number of algorithms for gene identification were created. These algorithms use fixed gene features which are chosen based on observation or experience. These features may not be major features of a genome. In this paper, we illustrate several candidate features and propose a dynamic feature choosing algorithm to determine the major features. We describe nucleotide sequence by feature vector and use Discriminant analysis to them to make decision on coding/non-coding. To test the algorithm, we apply the algorithm to the S.cerevisiae genome and achieve accuracy of above 98%. [ABSTRACT FROM AUTHOR]

In medical imaging, many applications require visualization and analysis of three-dimensional (3D) objects. Visualization is the process of exploring, transforming, and view data as images to gain understanding and insight into the data, which requires fast interactive speed and high image quality. In this paper, we describe the key techniques in medical image visualization. In order to improve ray casting rendering speed, a synthetically accelerated algorithm is proposed. Firstly, rendering algorithms are fully studied and compared. Secondly, proximity clouds algorithm has been selected and extended to continuous ray casting. Finally, the accelerated algorithm based on ray coherence has been realized. The experimental results on 3D medical image reconstruction are given, which show the medical image visualization technology has provided a powerful technology base for computer-aided diagnosis, virtual surgery and e-learning in medicine field. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is one of the most common cardiac diseases that cause morbidity and mortality. One of the most frequently used clinical treatments of AF is to use a large and brief external electrical shock to reset atrial tissue from a disordered fibrillation state to a quiescent state, then the pacemaker of the heart resumes its control of atrial excitation rhythm and thus a defibrillation is achieved. Though widely used in practice, the mechanisms underlying the success of an electrical shock in defibrillation is incompletely understood. In this study, we developed a computer model of human atrial tissue to investigate the actions of an external electrical shock on atrial excitations. Using the model, we computed the defibrillation threshold of the human atrium. We found that due to the supernormal excitability of human atrium, the computed successful defibrillation threshold is much less than the excitation threshold of human atrium in resting state. This study provides some new insights to understand the mechanisms underlying AF defibrillation. [ABSTRACT FROM AUTHOR]

The direct anchorage of a lower-limb prosthesis to the bone has been shown to be an excellent alternative for amputees experiencing complications in using a conventional prosthetic socket. After surgical implantation, amputees have to go through a weight bearing exercise program to prepare the bone to tolerate forces and promote bone-remodeling. Currently, the load magnitude prescribed by the clinician is measured by a weight scale which reports only the axial force in the limb. Previous study using a load transducer revealed that in addition to the axial force there were other forces and moments. This study develops a FE model and utilizes our load data to investigate the stress distribution at the bone-implant interface. The model shows that the stress distribution could be highly non-uniform during the exercise. Bone-implant interface stress has certain implications in pain adaptation and bone-remodeling, and a good understanding of it can assist in future attempts to refine and shorten the period of rehabilitation exercise. [ABSTRACT FROM AUTHOR]

Coronary artery diseases are usually revealed using X-ray angiographies. Such images are complex to analyze because they provide a 2D projection of a 3D object. Medical diagnosis suffers from inter- and intra-clinician variability. Therefore, reliable software for the 3D modeling of the coronary tree is strongly desired. This paper focuses on the automatic 3D modeling of the vessels from X-ray angiography. Our approach is based on a 3D model of standard vessels. The model is projected because it is difficult to suitably transform standard into individual vessels on 3D space. The modeling process is carried out in two steps. The first step consists of selecting automatically two sets of corresponding control points between standard and individual vessels. In the second step, 3D model of individual vessels is performed by warping with corresponding control points. Accurate descriptions of 3D model would be useful for quantitative diagnosis of atherosclerosis, for surgical or treatment planning, for monitoring disease progress or remission, and for comparing efficacies of treatments. Index term: Coronary Angiography, Control point, Image Transformation, 3D Modeling. [ABSTRACT FROM AUTHOR]

In order to access the effects of shoe-heel height on knee muscle activity for transtibial amputees during standing, five male subjects volunteered for the study. Three pairs of shoes with zero, 20 mm and 40 mm heel height were used during normal standing. Surface EMG of 10 muscles was recorded by the Noraxon surface EMG collection system. EMG-MAV of the medial and lateral gastrocnemius of the sound leg almost change double with increase in heel height from zero to 40 mm, and EMG-MAV of the rectus fomris, vastus lateralis and vastus medialis of prosthetic side became larger to different extent. The finding in this paper suggested that an alignment change was necessary to accommodate the heel height change and the prostheses users should be cautious to choose shoes in daily life. [ABSTRACT FROM AUTHOR]