Papers by Keyword: Shape

Abstract: The most common body parts that sustain injuries at the workplace are the hands and fingers. In association to this, researchers have conducted various studies on grip span, forces, postures, contact area and strength. However, it appears that limited studies have been done on the design of screw knobs of ergonomic shapes and sizes for pinch grip activities. Thus, the aim of this study is to design, develop and assess screw knobs of ergonomic shapes and sizes for pinching activities. Several designs of screw knobs were designed and fabricated. The assessment of the knobs involved workers from a manufacturing firm. The ratings on the efforts to pinch and turn the knobs were collected using surveys and analyzed with reliability and descriptive and analyses. The results show that the workers mostly preferred using the small 5-lobes knob. However, the large ball knob was the least preferred knob to be used. The findings of this study can be used to create design guidelines on knob shapes and sizes to develop safer, more ergonomic and efficient knobs.

Abstract: In this paper analytical predictions of the fusion zone shapes around the welding cavity produced by a moving electron beam are provided. A three-dimensional analytical model in the molten and heat-affected regions surrounding a paraboloid of revolution-shaped cavity is used to predict the shapes of the fusion zones. This work avoids the defect of the infinite temperature at the cavity base for the line-source model. Introducing a new image method, a new analytical solution is provided by satisfying exactly the adiabatic condition at the top surface. The shape of a fusion zone is governed by dimensionless parameters related to beam power per unit penetration, and the depth and shape of the cavity in this work. A three-dimensional shape of fusion zone is computed and presented in this paper. The effect of beam power per unit penetration on the shape of fusion is also discussed.

Abstract: Well-crystallized SrWO₄ mesocrystals with different shapes including flower-like sphere, bundle, peanut, dumbbell, and notched sphere were controllably synthesized via a simple microwave-assisted precipitation method. X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) measurements were used to characterize these mesocrystals. XRD patterns indicate that the SrWO₄ mesocrystals present a scheelite-type tetragonal structure. FESEM and HRTEM micrographs showed different shapes for the SrWO₄ mesocrystals. The molar ratio of [WO₄^2-] to [Sr²⁺] was found to play an important role in the morphological controlling of the resulting SrWO₄ mesocrystals. With the increase of the molar ratio, the shape of the SrWO₄ mesocrystals changed from flower-like sphere assembled with nanorods to notched sphere with intermediate peanut and dumbbell shapes. PL spectra measurements showed that the luminescence properties of the SrWO₄ mesocrystals strongly relied on its shapes.

Abstract: A clamping robot serving for several NC machines can recognize the best fit in manny blank parts. Forthermore, the shape information acquisition and pose measurment can be achieved by its computer vision system. The key question is that the clamping robot automatively choices the best fit part by statistical result of geometric dimension of all parts. The best fit part is the one that its length and its diameter are mostly proximate to the processing requirement. This choice method can save staff, reduce working allowance, and lessen finished cost. According to the shape information and position information, the robot can confirm the grab order, grab angle and finger joint distance. Firstly, the part image is smoothing by noise reduction technology, secondly, the feature points are extracted. The feature points present the information of the location of the mass center, the dip angle and diameter. Finally, the clamping robot can grab the most fit bar part by means of rotational motion, rectilinear motion, and finger open-close movement when the shape information and location information of the bar part have been confirmed.

Abstract: Content Based Video Retrieval (CBVR) is becoming a hot research topic. We lay a strong emphasis on the research of texture and shape character pick-up algorithm and retrieval technology, explain the meaning of the parameter of Gray-Level Co-occurrence Matrix, and compare the result of three algorithmCanny, Laplacian and Sobel. The article selects Canny and Gray-Level Co-occurrence Matrix in this system. The experiments show that the performance of the retrieval system based on texture and shape is related with each other, especially in searching the image with typical texture and shape character.

Abstract: The deep narrow groove of the coupling plate and side with WC-CO coating was grinded by diamond wheel with metal bond and vitrified bond. The side of the deep trench flatness error was less than 0.02 mm, the bottom of the tank around the corner radius was less than 0.3mm. The type of porosity, particle sizes, surface roughness were measured by experiments, the data for the selection of the grinding wheel bond varieties. The experimental results show that grinding wheel with vitrified bond was suitable for parts of small coating porosity, fine particle size, surface roughness, and others were suitable for the grinding wheel with metal binder.

Abstract: The ring shape chain was shaped by twice shape at two set die at present technology of works. It should be improved in structure. At first, the bar, which was passed through a shaped ring, was orientation on the upper punch , and the elasticity upper punch and side pressure block were used in die, the bar was bended into U shape, then, the side pressure block will pressure the open ends of U shape bar , at last , a ring chain was shaped at the die. The structure of this kind of die is not complex, but, it can reduce a shape process and a shape die, also reduce a half labor time. This die has high dependability, simply use and has extremely extend value.

Abstract: To reduce carbon dioxide emissions from buildings, we selected housing shape as research object. By deforming a simplified detached house model, we achieved optimal shape of WDH reducingLCCO2 by Genetic Algorithms (GA).

Abstract: Among all elements of building which related to CO2 emissions, building shapes is a decisive factor. By deforming a cubic model, we achieved optimal shape of WDH reducingLCCO2 by Genetic Algorithms (GA).

Abstract: A Constrained Local Models is face tracking method based on variation of shape in the Allowable Shape Domain. The CLMs perform optimize strategy in patch. It has problem because occlusion and background. In this paper, variation of shape is constrained for solving this problem.The generating of shape allows only shape adjusted translation, rotation, scale. The proposed method prevent that the shape generate to abnormal forms. As a result, the alignment error is about 4.2 pixels in environment has complex background. Also, when part of the face occluded, the alignment error is about 18.1pixels.