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41.
A simplified geometric model with lower dimensionality, such as a mid-surface model, is often preferred over a detailed solid model for the analysis process, if the analysis results are not seriously impacted. In order to derive a mid-surface model from a thin-walled solid model, in this paper, we propose a novel approach called the solid deflation method. In this method, a solid model is assumed to be created by using air to inflate a shell that comprises the surface of the solid model. First, the model is simplified by the removal of any detailed features whose absence would not alter its overall shape. Next, the solid model itself can be converted into a degenerate solid model with zero thickness. Finally, a surface model is generated by splitting large faces paired in the thinned solid model, selecting one face per pair for creating a sheet model, and sewing the selected faces. Using this method, a more practical and usable mid-surface model can be very efficiently generated from a solid model because it can circumvent not only the tedious trimming and extension processes of the medial axis transformation method but also the time-consuming patch joining process of the mid-surface abstraction approach.  相似文献   
42.
Various types of polymer surfaces with a nanolens array, which has an entrant shape with a low aspect ratio, were fabricated and the wettability of the fabricated surfaces was evaluated in both theoretical and experimental ways. The nanolens array was replicated on three different polymer surfaces of polydimethylsiloxane (PDMS), cyclic olefin copolymer (COC), and polymethylmethacrylate (PMMA) by means of replica molding and hot embossing with a nanodimpled aluminum mold that was manufactured by a chemical oxidation process. From the theoretical and experimental evaluations of the wettability it was found that the measured contact angles were very similar with the theoretically estimated ones and also the hydrophilicity and hydrophobicity of the hydrophilic PMMA and hydrophobic PDMS, respectively, surfaces were reinforced by the nanolens array within the Wenzel wetting state.  相似文献   
43.
Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed.  相似文献   
44.
This article describes the performance comparison of several tracking filters from the viewpoint of gun fire control. It is common that filter performance can be represented by the RMSE of the current state. However, for the design of a gun fire control system, the performance of the tracking filter in terms of prediction is more important since the current state proceeds with a designed dynamic model to a certain future which is used for the final gun order. It is shown that the predicted results amplify the current state RMSE and can be a good measure.  相似文献   
45.
In this study, a simulation model for a powered hip orthosis (PHO) with air muscles to predict the gait of paraplegics is presented which can be used as a design tool for hip orthoses. Before simulation, mathematical models for a human dummy with an orthosis and a pneumatic muscle actuator were generated. For the air muscle, coefficients required were obtained by static and dynamic experiments of the air muscle and experiments for the valve controlling the air pressure. The computation was conducted on the ADAMS package together with MATLAB. Computer simulation of the flexion of hip joints by the pneumatic muscle results in similar values to those from gait analysis. With the development of a simulation model for a PHO, the gait simulation model using pneumatic muscles can be used to analyze and evaluate the characteristics and efficiency of a PHO by setting the input and boundary conditions.  相似文献   
46.
This paper describes the design and fabrication of a MEMS guide plate, which was used for a vertical probe card to test a wafer level packaged die wafer. The size of the fabricated MEMS guide plate was 10.6 × 10.6 cm. The MEMS guide plate consisted of 8,192 holes to insert pogo pins, and four holes for bolting between the guide plate and the housing. To insert pogo pins easily, an inclined plane was defined at the back of each hole. Pitch and diameter of the hole were 650 and 260 μm, respectively. In order to define inserting holes and inclined planes at an exact position, silicon MEMS technology was used such as anisotropic etching, deep reactive etching and more. Silicon was used as the material of the guide plate to reduce alignment mismatch between the pogo pins and solder bumps during a high temperature testing. A combined probe card with the fabricated MEMS guide plate showed good xy alignment and planarity errors within ±9 and ±10 μm at room temperature, respectively. In addition, xy alignment and planarity are ±20 and ±16 μm at 125°C, respectively. The proposed MEMS guide plate can be applied to a vertical probe card for burn-in testing of a wafer level packaged die wafer because the thermal expansion coefficient of the MEMS guide plate and die wafer is same.  相似文献   
47.
The rise of online social media has led to an explosion of metadata-containing user generated content. The tracking of metadata distribution is essential to understand social media. This paper presents two statistical models that detect interpretable topics over time along with their hashtags distribution. A topic is represented by a cluster of words that frequently occur together, and a context is represented by a cluster of hashtags, i.e., the hashtag distribution. The models combine a context with a related topic by jointly modeling words with hashtags and time. Experiments with real-world datasets demonstrate that the proposed models discover topics over time with related contexts effectively.  相似文献   
48.
This paper examines characteristics of interactive learning between human tutors and a robot having a dynamic neural-network model, which is inspired by human parietal cortex functions. A humanoid robot, with a recurrent neural network that has a hierarchical structure, learns to manipulate objects. Robots learn tasks in repeated self-trials with the assistance of human interaction, which provides physical guidance until the tasks are mastered and learning is consolidated within the neural networks. Experimental results and the analyses showed the following: 1) codevelopmental shaping of task behaviors stems from interactions between the robot and a tutor; 2) dynamic structures for articulating and sequencing of behavior primitives are self-organized in the hierarchically organized network; and 3) such structures can afford both generalization and context dependency in generating skilled behaviors.  相似文献   
49.
Proteins consist of atoms. Given a protein, the automatic recognition of depressed regions, called pockets, on the surface of proteins is important for protein-ligand docking and facilitates fast development of new drugs. Recently, computational approaches have emerged for recognizing pockets from the geometrical point of view. Presented in this paper is a geometric method for the pocket recognition which is based on the Voronoi diagram for atoms. Given a Voronoi diagram, the proposed algorithm transforms the atomic structure to meshes which contain the information of the proximity among atoms, and then recognizes depressions on the surface of a protein using the meshes.  相似文献   
50.
In this paper, we present the ARIA media processing workflow architecture that processes, filters, and fuses sensory inputs and actuates responses in real-time. The components of the architecture are programmable and adaptable; i.e. the delay, size, and quality/precision characteristics of the individual operators can be controlled via a number of parameters. Each data object processed by qStream components is subject to transformations based on the parameter values. For instance, the quality of an output data object and the corresponding processing delay and resource usage depend on the values assigned to parameters of the operators in the object flow path. In Candan, Peng, Ryu, Chatha, Mayer (Efficient stream routing in quality- and resource-adaptive flow architectures. In: Workshop on multimedia information systems, 2004), we introduced a class of flow optimization problems that promote creation and delivery of small delay or small resource-usage objects to the actuators in single-sensor, single-actuator workflows. In this paper, we extend our attention to multi-sensor media processing workflow scenarios. The algorithms we present take into account the implicit dependencies between various system parameters, such as resource consumption and object sizes. We experimentally show the effectiveness and efficiency of the algorithms.
Kyung Dong RyuEmail:
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