• Title/Summary/Keyword: contouring method

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Surface contouring using Electronic Speckle Pattern Interferometry (전자 스페클 패턴 간섭계를 이용한 형상 측정)

  • 김계성;유원재;강영준
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.397-401
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    • 1995
  • ESPI(Electronic Speckle Pattern Interfermetry) is an optical technique to measure surface deforamtion of engineering components and materials in industrial ares. This optical method is capable of providing full-field results with high spatial resolution, high speed and is the non-contact technique. One of important application aspects using electronic speckle pattern interferometry is to generate contours of a diffuse object in order to provide data for 3-D shape analysis and topography measurement. The contouring method by modified dual-beam speckle pattern interferometry is proposed. We introduce a shift of the illumination beams through optical fiber in order to obtain the contour fringe patterns. The speckle pattern correlation technique is suitable for providing measurement range from millimeters to several centimeters. The complete geometric analysis of the contoretical and experimental results are obtained.

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Cross-Coupling Controller for High-Speed Nonlinear Contour Machining (고속의 비선형 윤곽가공을 위한 교차축 연동제어기)

  • Jee, Sung-Chul;Lee, Yong-Seok
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.446-451
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    • 2000
  • In this paper, a new adaptive cross-coupling control (CCC) algorithm with an improved contour error model is proposed to maintain contouring precision in high-speed nonlinear contour machining. The proposed method utilizes variable controller gains based on the instantaneous curvature of a contour and the feedrate command. The proposed method is evaluated and compared with the conventional CCC for nonlinear contouring motion through computer simulations. The simulation results show that the proposed CCC improves the contouring accuracy more effectively than the existing method.

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Improvement of Contour Fringes by using Addition of Incremental Images

  • Kang, Young-June;Ryu, Weon-Jae;Park, Sang-Kyu
    • International Journal of Precision Engineering and Manufacturing
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    • v.3 no.3
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    • pp.37-43
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    • 2002
  • Electronic speckle contouring(ESC) based on electronic speckle pattern interferometry is the optical method for measuring object shape by using fringe-projection techniques. This method has the advantages of being non-contact, non-destructive and a whole-field measurement of the surface under investigation. Fringes in ESC represent the difference in depth along the view direction between the master wavefront and the test component. The contour maps of three-dimensional diffuse objects can be obtained by small shifts of optical fiber carrying the dual-object-beams and 4-frame phase shifting. In this study we proposed the contouring method by shifting the collimated illumination beams through optical fiber in order to obtain the contour fringe patterns. And also, we performed the addition of incremental images through the geometrical analysis to obtain the contour fringe interval when we performed the incremental addition of images and experiments based on this method. We obtained both quantitative increment without decorrelation effect and qualitative improvement by reducing the noise of contour fringes.

The Comparison of Image Quality Using Body Contour and Circular Method with L-mode in Myocardial Perfusion SPECT (Tl-201을 이용한 심근관류 SPECT에서 Body contour와 Circular mode의 영상 획득 차이에 따른 영상의 질 비교)

  • Kim, Sung-Hwan;Nam, Ki-Pyo;Ryu, Jae-Kwang;Yoon, Soon-Sang
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.3-7
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    • 2012
  • Purpose : In myocardial perfusion SPECT, the type of orbit (circular vs. body contouring) that affect the image quality is still on the debate. Presently in the nuclear medicine field, the body contouring orbit acquisition is widely used to improve the image quality on the myocardial perfusion SPECT. But in case of body contouring acquisition using the vertical method with dual detect machine, there is a tendency of increasing the radius. In this research, we compared body contouring orbit acquisition with circular orbit acquisition, so we suggest ideal method that reduces the radius for improving image quality. Materials and Methods : Phantom and clinical studies were performed. The anthropomorphic torso phantom was made on equally with counts from patient's body. The study was performed under six different conditions. To compare image quality according to the radius, we increased radius sequentially per step during circular orbit acquisition. On the other hand, sensors that protect a collision and reduce the radius automatically were used to acquire image during body contouring orbit acquisition. So we compared FWHM value of apex. In clinical studies, we analyzed the 40 patients who were examined by Tl-201 gated myocardial perfusion SPECT in department of nuclear medicine at Asan Medical Center in August 2011. To acknowledge the differences according to the radius, we acquired the results two times using circular orbit acquisition and body contouring orbit acquisition. Results : In phantom study, we analyzed that increase of radius resulted in changes of FWHM value. It was 5.41, 6.24, 6.33, 6.42, 6.93 mm. On the other hand, using the body contouring orbit acquisition, FWHM value was 6.23 mm. In clinical study, difference of average radius between two methods was 2.5 cm (circular orbit acquisition was more close to patients). Conclusion : Through the experiments using Anthropomorphic torso phantom and patients data, we found that FWHM value of circular orbit acquisition was lower than body contouring orbit acquisition. As a result, if the difference of average radius exists approximately 3 cm, circular orbit type acquisition is better than body contouring type acquisition. But clinical investigation is only aimed to average radius, so it needs more investigation in comparison of patient's image.

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Evaluation of the effects of mandibular angle sagittal ostectomy and botulinum toxin type A treatment using facial golden mask (황금마스크를 이용한 하악각시상골절제술과 보툴리눔독소 치료법의 평가)

  • Shin, Seung-Kyu;Kim, Yong-Ha;Kim, Tae-Gon;Lee, Jun-Ho;Ahn, Ki-Young
    • Archives of Plastic Surgery
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    • v.36 no.4
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    • pp.469-474
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    • 2009
  • Purpose: A lower facial contouring surgery has become a commonly performed procedure in Asia. Currently, mandibular angle sagittal ostectomy and botulinum toxin type A treatment are main procedures for aesthetic correction of a broad lower face. There are a few date to show the differences in the mandibular contouring changes between mandibular angle splitting ostectomy and botulinum toxin type A treatment. Facial golden mask is easy to apply, inexpensive, and relatively objective for evaluation of facial contour analysis. This study was designed specifically to compare the changes in lower face width after two different forms of lower facial contouring procedure using facial golden mask. Methods: Seventeen patients, aged 18 to 55 years (mean, 28.6 years), 15 women and 2 men, consented to the study and receive a contouring procedure of lower face. The patients were classified in to 2 groups. In group A, the sample consisted of 10 patients with a prominent squared mandibular angle and mandibular angle splitting ostectomy was performed. In group B, the sample consisted of 7 patients with masseteric hypertrophy and botulinum toxin type A treatment was performed. Photographs of the face were taken to record the facial change at preoperative and postoperative. The postoperative photographs were taken to considered maximal effect at 2 years after surgery in group A and 4.8 months after treatment in group B. The authors applied the facial golden mask to preoperative and postoperative photographs and horizontal ratio, which compares facial width with golden mask width, were calculated. We made an analysis of the result of horizontal ratio using SPSS. Results: Overall average horizontal ratio of pre- and postoperative photos of group A were 1.24 and 1.11, whereas overall average horizontal ratio of pre- and postoperative photos of group B were 1.19 and 1.12. The horizontal ratio decreased 10.24% in group A and 5.93% in group B. There was a statistically significant change in before and after treatment, but there was no significant change in comparing the group A and group B. Conclusions: The result from this study suggest that mandibular angle sagittal ostectomy and botulinum toxin type A treatment showed relatively satisfactory clinical effects on lower facial contouring treatment. There was no statistical significant difference within two lower facial contouring treatment. Facial golden mask is easy to apply, inexpensive, and relatively objective, so we think that facial golden mask is a good method for evaluation of lower facial contouring treatment.

Digital Contouring Control of Biaxial System (2축 디지틀 윤곽제어)

  • Lee, Gun-Bok;Ko, Tae-Geun
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.435-437
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    • 1998
  • In this productive system, it needs to control the each axis motion harmoniously to perform accurately for the manufacturing, transporting and printing. Independent Axis Control usually used for this objection. However, if Independent Axis Control mismatched the parameter of each axis system or in the case of free curve tracking or the case of high speed control, there would be big contour error so that cannot achieve control objection. As a result, there is Contour Control method suggested to supply for this defect. This paper carried modeling of biaxial system and implemented Independent Axis Control & Contouring Control on straight line, circular, and coner path by simulation and experiment. If feedrate increased, contour error growed. In consequence, according to this factor, we introduced contouring controller, so we could find the fact that contour error was reduced more than that of independent axis control about each path.

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Slimming of Lower Face by Contouring of the Mandibular Body in Orthognathic Surgery Patients

  • Park, Bong-Wook;Kang, Young-Hoon;Choi, Mun-Jeoung;Kim, Si-Yeob;Kang, Hea-Gea;Kim, Jong-Ryoul;Byun, June-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.5
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    • pp.325-330
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    • 2013
  • The patient's appearance can be dramatically enhanced as a result of orthognathic surgery. However, esthetic contouring of the mandibular body portion is often overlooked in the surgery. Restoring a more beautiful jaw line is important and directly affects surgical results. From December 2010 to February 2012, we performed mandibular body contouring for the slimming of the third lower part of the face in 37 patients who had undergone either 1-jaw surgery or 2-jaw surgery. The third lower part of the facial contour was improved in all the patients after at least 3 months follow-up. Mandibular body contouring is a simple method that can be additionally used for the slimming of the third lower part of the face in patients who require orthognathic surgeries. It makes the lower face look more attractive from both the anterior and lateral perspectives.

Upper Arm Contouring with Brachioplasty after Massive Weight Loss

  • Han, Hyun Ho;Lee, Min Cheol;Kim, Sang Hwa;Lee, Jung Ho;Ahn, Sang Tae;Rhie, Jong Won
    • Archives of Plastic Surgery
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    • v.41 no.3
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    • pp.271-276
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    • 2014
  • Background As the obese population increases in Korea, the number of patients who are trying to lose weight has been increasing steadily. In these patients, skin laxity and deformation of the body contour occurs, which could possibly be corrected by various body contouring surgeries. Here, we introduce the brachioplasty method and our experience of various body contouring surgeries performed in our center. Methods From November 2009 to August 2011, five cases of brachioplasty were performed. When the patient presented with sagging of the lateral inframammary crease and bat wing deformity in the axilla, extended brachioplasty was performed; in this case, the deformation of the axilla and lateral chest was corrected at the same time. A traditional brachioplasty was performed when contouring was needed only for skin laxity in the upper arm. Results Complications, such as hematomas or nerve injuries, were not evident. Some patients experienced partial wound dehiscence due to tension or hypertrophic scars found during the follow-up. In general, all of the patients were satisfied with the improvement in their upper arm contour. Conclusions Given the demands for body contouring surgery, the number of brachioplasty surgical procedures is expected to increase significantly, with abdominoplasty comprising a large portion of these surgeries. For the brachioplasty procedure, preparation and preoperative consultation regarding design of the surgery by experienced surgeons was important to prevent complications such as nerve damage or hematoma formation.

Improvement of Contour Fringes by using Addition of Incremental Images (화상 증분 축적법을 이용한 등고선 간섭무늬의 개선)

  • Kang, Young-June;Kim, Gye-Sung;Ryu, Weon-Jae;Kwon, Yong-Ki
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.12
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    • pp.190-197
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    • 1999
  • Electronic speckle contouring(ESC) is the optical method for measuring shape by using fringe-projection techniques in electronic speckle pattern interferometry. It has the advantage of being non-contacting and can also give a field view of the surface under investigation. Fringes in ESC represent the difference in depth along the view direction between the master wavefront and the test component. The contour maps of three-dimensional diffuse objects are obtained by small shifts of optical fiber carrying the dual-object-beams and 4-frame phase shift. We proposed the contouring method by shifting the collimated illumination beams through optical fiber in order to obtain the contour fringe patterns. And also, we performed addition of incremental addition of images and experiments based on it. we obtained both quantitative increment without decorrelation effect and qualitative improvement by reducing the noise of contour fringes.

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Surface Extraction from Multi-material CT Data

  • Fujimori, Tomoyuki;Suzuki, Hiromasa
    • International Journal of CAD/CAM
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    • v.6 no.1
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    • pp.81-87
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    • 2006
  • This paper describes a method for extracting surfaces from multi-material CT (Computed Tomography) data. Most contouring methods such as Marching Cubes algorithm assume that CT data are composed of only two materials. Some extended methods such as [3, 6] can extract surfaces from the multi-material (non-manifold) implicit representation. However, these methods are not directly applicable to CT data that are composed of three or more materials. There are two major problems that arise from fundamentals of CT. The first problem is that we have to use n(n-1)/2 threshold values for CT data contains n materials and select appropriately one threshold value for each boundary area. The second is that we cannot reconstruct only from CT data in which area three or more materials are adjacent each other. In this paper, we propose a method to solve the problems by using image analysis and demonstrate the effectiveness of the method with application examples construct polygon models from CT data of machine parts.