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This clinical report describes the immediate implant placement and restoration for a 47-yearold woman with a protruded and loose maxillary right central incisor. The treatment included minimally invasive extraction, flapless immediate implant placement using a fully guided surgical template, and immediate implant-supported provisionalisation. The interim anatomical prosthesis was fabricated in advance based on preoperative CBCT scans, and the digital technique made it possible to integrate data precisely from different sources. After 6 months of provisionalisation, satisfactory gingival aesthetic and functional improvements were achieved, followed by a definitive screw-retained zirconia restoration. Thus, application of a complete digital workflow could reduce chairside time and create an optimal emergence profile that matches the residual bone architecture of the extraction sites with minimal interference.

Traffic flow video processing is an important direction of the development of intelligent transportation, Gaussian mixture background modeling is one of commonly algorithms to build background modeling that is widely used in image processing field. In order to analysis the algorithm comprehensively ,in this paper, it calculus on formula as well as tests and compares some traffic flow videos, the solution based on the K-means, EM parameters model are presented, it gets the mathematical meaning and evolution process of the algorithm clearly by calculating formulas to provide theoretical guidance for practical application; the traffic flow videos processing can get the treatment ability of this algorithm according to the different situation of videos, analyze the mixed Gauss background modeling for time migration, the light changing, moving object shadow processing ability. In this paper, the algorithm of mixed Gauss background modeling is analyzed from two aspects of theory and application.

This paper proposed a new method of feature description for insulator species recognition. A method of calculating the difference was defined. The three component value matrixes of an image in HSI space were converted to difference value matrixes successively. Then the difference value, shape and angle features of each region and each color were described. Experiments showed that the proposed method can be applied to describe the actual aerial images, and achieved the recognition of insulator species.

In this paper, detailed process of Scale-invariant Feature Transformation (SIFT) algorithm is analyzed. For its weaknesses, the difference measure theory is introduced, and then a new improved method is proposed. At first, the gray value matrix of image is converted to the difference value matrix based on the knowledge of fuzzy membership. The non-linear relationship between human eye sensitivity and differences of image gray value changes into a linear relationship. And then SIFT feature points are extracted and matched based on the difference value of pixel. The experimental results based on standard image datasets demonstrate that, this method can reduce the complexity of the algorithm and improve the matching rate at the same time; the efficiency of the algorithm is also improved.

Disparity estimation is a basic analytic method for images and video and is highly used in fields like stereo image coding, video retrieval and stereo image segmentation. This paper proposes a new disparity estimation method. In this paper, the superiority of the multi-block matching is analyzed. The new method based on the idea of block matching constructs a multi-block matching algorithm, thereby improving matching accuracy especially in the disparity discontinuous regions. A adaptive window method based on edge detect is proposed to select the best window.The experimental results based on the Middlebury stereo datasets demonstrate that our method can achieve a better performance.

This study presents the development of a cost-effective high-precision bench machine tool prototype for machining multi-level micro aspheric lighting-lens molds. To achieve high-precision over a long lifetime of micromachining, the bench machine tool is designed using a small C-shaped framework to strengthen static rigidity and vibration resistance. The primary structures of the machine tool are constructed with tempered nodular graphite cast iron to obtain a high damping coefficient and high inherent resonant frequency. A multi-level aspheric curve generator is designed according to the multi-level aspheric curve equation to easily create an aspheric curve and then rotated into an aspheric surface form with a symmetrical optical axis. The verifications of the designed bench machine tool’s functions were conducted by machining the micro aspheric lighting-lens molds using high-speed micro milling. Experimental results demonstrate that form accuracy and surface roughness for the micro aspheric lightinglens mold of Rt 2.937 μm and Ra equal to 0.032 μm respectively could be simultaneously achieved. The developed cost-effective bench machine tool can supply high-quality and fast machining in the fabrication of micro optoelectronic molds such as those used for micro aspheric lighting-lenses.

This study presents the development of a grinding–drilling technique for an innovative bench-top drill that combines micro-EDM with grinding and drilling to fabricate micro-holes in optical grade glass. Firstly, a novel diamond-tool, made with copper-based sintered alloy, is designed and fabricated on-line into a harbor-shaped structure with a hollow shaft and negative back rake-angles. Constructed reverse co-centric micro-hole EDM-drilling and reverse w-EDM facilitate on-line machining of the diamond-tool, which can then be directly utilized to drill micro-holes in optical glass and quartz. Application of a load-cell that detects the drilling force in real-time, providing feedback for fine tuning the feed-rate of the tool is proposed. Experimental results show that excellent geometric and dimensional accuracy of micro-holes can be achieved. The estimated reasonable tool life is determined at a machining number of 30 times. The proposed grinding–drilling technique is simple, cost effective, and can significantly contribute to the precision micromachining industry.

This study presents the development of a drilling technique for an innovative tabletop drilling machine that combines micro-EDM with drilling to fabricate micro-holes in diamond-tool. The mechanisms designs of double V-shaped bearings and double spindles which provide a precision clamping and vertical alignment for diamond-tool and micro-tube are devised to enable to machine a co-centric micro-hole for micro-tool. A diamond-tool, made with copper-based sintered alloy, is drilled by using the developed technique of co-centric micro-hole EDM-drilling into a hollow shaft which can create equilibrium of drilling forces, prevent a drilling squeezing to be occurred and enable to offer a temporary storing space for drilling chips. Relative experiments including the determinations of drilling ratio and discharge capacitance are carried out via this established machine. Experimental results show that excellent geometric and dimensional accuracy of micro-holes on the diamond-tool can be achieved.

This paper proposed a new method of feature description for target recognition and matching. Firstly, a method of calculating the difference was defined. The gray value matrix of an image was converted to a difference value matrix. Then the difference value, shape, angle and other features of a region and the combined features between regions were described. Finally, the method was applied to identify traffic signs. Experiments showed that the proposed method can represent multiple features of image such as the gray differences, the shape changes, and so on. Through theoretical and simulation analysis, even under rotation, shift or scale transformation, new features description method still can correctly recognize the target. http://dx.doi.org/10.11591/telkomnika.v12i12.6568

The purpose of this study was to develop the on‐machine measurement techniques so as to precisely fabricate micro intricate part using ultra‐fine w‐EDM. The measurement‐assisted approach which employs an automatic optical inspection (AOI) is incorporated to ultra‐fine w‐EDM process to on‐machine detect the machining error for next re‐machining. The AOI acquires the image through a high resolution CCD device from the contour of the workpiece after roughing in order to further process and recognize the image for determining the residual. This facilitates the on‐machine error detection and compensation re‐machining. The micro workpiece and electrode are not repositioned during machining. A fabrication for a micro probe of 30‐μm diameter is rapidly machined and verified successfully. Based on the proposed technique, on‐machine measurement with AOI has been realized satisfactorily.

In this study on-machine measurement-assisted techniques are utilized in combination with micro-EDM to successfully machine intricate micro-parts. Two measurement approaches, automatic optical inspection (AOI) and critical contact measurement (CCM), are used on a previously built machine tool. AOI acquires the image from the contour of the machined workpiece and further processes the image to determine the finish allowance. CCM measures on-line the consumption of the microelectrode to create an accurate compensation rate. These two non-contact measurement techniques facilitate on-machine error detection and re-machining during micro-EDM. Significant work efficiency and preservation of machining accuracy are gained by having the workpiece and tool remain in place throughout machining procedures. A micro-probe with a diameter of 30 µm and a micro 3D engraving mold on a small tungsten steel ball are perfectly fabricated and verified, respectively.

A precision ultrafine w-EDM (wire electrical discharge machining) technique specifically for machining intricate parts and structures is developed in this paper. A thumb-sized and versatile w-EDM device equipped with a complete control system for wire tension (ultrafine tungsten wire of 13 µm diameter) is designed and employed for the study of ultrafine w-EDM. The tension of the wire electrode is controlled by magnetic repulsive force to steady the wire during machining. Ultrafine wire cutting can be conducted in vertical-, horizontal- or slantwise-wire arrangements. Via some experiments, optimal machining conditions including discharge capacitance, feed rate, wire tension and the appropriate design for the w-EDM device are obtained. Two miniature samples including a micro of Taipei's landmark 101 building and a micro relay are fabricated and the feasibility of the proposed approach is verified. It is confirmed that the ultrafine w-EDM technique using an ultrafine tungsten wire of 13 µm was realized successfully.