• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1997년도 동계 학술대회 논문집
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• pp.375-384
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• 1997

굴을 까는 작업은 굴의 껍질 에 붙어있는 근육질과 굴 껍질에 붙어있는 hinge를 절단하는 작업을 필요로 한다. 본 논문은 굴을 까는 자동화기계를 개발하기 위한 하나의 단계로서 굴의 hinge 의 위치를 판단하는 computer vision system 의 image processing software (영상처리)개발에 대하여 중점을 두었다. 본 실험에 사용한 굴들은 computer vision system이 굴의 바깥쪽 hinge 표면을 감지할 수 있도록 굴을 물로 씻은 후 굴 껍질의 hinge 부분을 약간 절단하였다. computer vision system은 color video camera를 이용하여 굴의 절단된 hinge표면의 영상을 잡은 후 image processing software를 이용하여 굴의 hinge 위치를 감지하였다. 본 논문에 사용한 computer vision software 는 일반 상용화된 software 와 굴의 hinge 위치를 알아내기 위해 저자가 연구 개발한 software 로 구성하였다. Image 내의 굴의 hinge와 그 밖의 다른 물질을 구별하기 위하여 본 논문의 software 는 4개의 변수 (circularity , Rectangularity, Aspect-ratio , Euclidian Distance)를 이용하였다. 또한 image 내의 굴의 hinge 위치를 쉽고 효과적으로 파악하기 위하여 몇 가지 영상처리, 즉, shrink-expand, thresholding 외의 다른 방법들을 이용하였다.

• Journal of Biosystems Engineering
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• 제22권2호
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• pp.237-246
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• 1997

굴 까는 작업을 자동화하기 위한 방법으로 굴의 껍질 안쪽에 붙어 있는 근육질을 제거하고 굴 껍질의 힌지(Hinge)를 절단하는 작업을 필요로 한다. 본 논문에서는 굴을 까는 자동화 기계를 개발하기 위한 연구의 일환으로써 컴퓨터 시각 시스템을 이용하여 굴의 힌지 위치를 판단하는 영상처리 알고리즘을 개발하였다. 본 실험에 사용한 굴들은 컴퓨터 비젼 시스템이 굴의 바깥쪽 힌지표면을 감지할 수 있도록 굴을 물로 씻은 후굴 껍질의 힌지(Hinge)부분을 약간 절단하였다. 칼라 비디오 카메라(color video camera)를 이용하여 굴의 절단된 힌지표면의 영상을 잡은 후 개발한 영상처리 알고리즘을 이용하여 굴의 힌지(hinge)위치를 감지하였다. 영상내의 굴의 힌지(Hinge)와 그 밖의 다른 물체를 구별하기 위하여 4개의 변수 (원형도, 사각형도, 장단축비, 유크리드(Euclidian)거리 )를 이 용하였다. 또한 영상(image)내 의 굴의 힌지(Hinge) 위치를 쉽고 효과적으로 파악하기 위하여 몇 가지 영상처리 즉, 수축-확장, 문턱갑 처리 등의 방법들을 이용하였다.

• International Journal of Reliability and Applications
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• 제5권1호
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• pp.15-24
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• 2004

Folder type electronic devices have hinge to support the rotational motion of folder. This hinge is stressed by the rotational inertia moment of folder at the maximum open limit position of folder. This stress is repeated whenever the folder is open, and it is a cause of hinge fracture. In this paper, the reliability evaluation for the hinge fracture in the folder type cellular phone is discussed. For this, the durability testing machine using crank-rocker mechanism is developed to evaluate the life cycle of the hinge, and the degradation after repetitions of opening and shutting is evaluated from the deformation around the hinge, where the deformation is measured by ESPI (electronic speckle pattern interferometer). Experimental results showed that ESPI was able to measure the deformation of hinge precisely, so we could monitor the change of deformation around the hinge as the repetition number of folder open is increased.

• 대한치과보철학회지
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• 제14권1호
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• pp.11-16
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• 1976

Casts are often transferred to the articulator by arbitrary means, because the method of locating the true hinge axis point thought to be a complicated and time consuming procedure, and because the importance and significance of the true hinge axis in the construction of dental prosthesis is not sufficiently understood. In this report, the author constructed the hinge axis locator and determined the variations in location of the true hinge axis points from the location of the hinge axis point determined by arbitrary means. For this report, the procedure was followed on 50 persons with normal occlusion and sound T.M.J. function, so 100 true hinge axis points were recorded and compared with the arbitrary hinge axis point. The results obtained were as follows. 1. The mean distance from the arbitrary hinge axis point to the true hinge axis point was as follows. Right; (O)5.17mm., (V)3.44mm., (H)3.55mm.. Left; (O)5.63mm., (V)3.95mm., (H)3.51mm.. 2. The percentage of true hinge axis points classified at intervals of 2mm was as follows. 0-2mm; 4%, 2-4mm; 21%, 4-6mm; 37%, 6-8mm; 26%, 8-10mm; 10%, Over 10mm; 2%. And only 50% of the 100 true hinge axis points were located within a 5mm. radius of the arbitrary hinge axis point. 3. Instead of transferring the casts to the articulator by arbitrary means, the careful location of the true hinge axis points is recommended to avoid potential sources of error in mounting casts.

• 한국정밀공학회지
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• 제20권2호
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• pp.168-175
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• 2003

In this research, a bridge-type flexure hinge mechanism is developed and optimized to amplify the displacement of a multilayer piezostack. Developed hinge mechanism has three-dimensional structure to reduce link size, so it have high amplification ratio with respect to small size. A flexure hinge is assumed to be 6 degree-of-freedom spring elements and matrix methods are used to model a hinge mechanism. To verify derived matrix model, a displacement and frequency experiments are performed. The analysis result shows that the displacemental error between matrix model and experiments is below 10 percents and the deformation of hinge in parasitic direction should be considered In hinge modeling. Using developed matrix model, an optimal design is performed to maximize the performance of hinge mechanism.

• 대한치과보철학회지
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• 제22권1호
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• pp.72-78
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• 1984

The notion that the axis of the shaft of the articulator must coincide the patient's mandibular transverse axis tells us the importance of locating the axis precisely. When using kinematic axis to transfer a cast to an articulator, the anatomic asymmetry of the contralateral points will result in certain distortion when the axis transferred to an articulator where the mechanical axis produces symmetry. In this study, after locating the true hinge axis point with Denar hinge axis locator, the discrepancies between true hinge axis point and arbitrary hinge axis point that was 13mm anterior from the posterior margin of center of trangus to the outer canthus of eye were measured. And the discrepancies between left and right true hinge axis point in the superoinferior and anteroposterior directions were measured. For this study, 20 dental students who have no missing teeth and no difficulties of mandibular movement were selected. Upper and lower cast of subjects were mounted on Denar Mark II articulator uisng Denar Slidematic face-bow and centric relation record for the measurement of discrepancies between left and right true hinge axis points. The results obtained as follows. 1. The mean distance from the arbitrary hinge axis point to the true hinge axis point was as follows. Right: horizontal distance; 1.99mm, vertical distance; 2.12mm, linear distance; 3.36 mm. Left: horizontal distance; 1.39mm, vertical distance; 2.06mm, linear distance; 2.09mm. Total: horizontal distance; 1.69mm, vertical distance; 2.09mm linear distance; 3.06 mm. 2. The 87.5% of true hinge axis points were within 5mm of the arbitrary hinge axis point. 3. The mean discrepancies between the right and left hinge axis point were 2.92mm in superoinferior direction and 4.74mm in anteroposterior direction. 4. When transferring the axis to the articulator, anatomic asymmetry between right: and left axis point produces in dislocation of cast on the articulator, and undesirable shift in esthetic tooth position will be resulted.

• 대한안전경영과학회지
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• 제14권2호
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• pp.49-54
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• 2012

As all kind of industry has developed, metal structure and machine instrument use bolt, pin, rivet and welding for assembly and combination. For pin and hinge, dimension accuracy is crucial to keep the operation and safety of the structure and machine instrument. In case of complex machine, the hinge for cover open-loop system is one of the significant design elements. Most of the hinges are being imported and assembled sine they give high technology development cost for its unit cost position. The reason is that the localization of hinge is inadequate. As the demand increase and the necessity of localization grow, it is now more important than ever to develop low cost structure. By the low cost structure, a new technology could be obtained for electronic product and structural hinge since it would enable for complex machine hinge to be guaranteed, technologically. Open-loop hinge is the link type and designed for the structure to keep constant open-loop. And, the hinge is examined in design stability by finite element analysis method. In this paper, the operation result is presented when the hinge for complex machine open-loop is designed for link type structure.

• 한국기계가공학회지
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• 제13권1호
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• pp.107-114
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• 2014

A friction hinge system which moves without power was designed and developed using the principle of friction force, which is caused by interference between the inner diameter of a silicon cap and the outer diameter of a cylindrical roller bearing with one-way rotation in a counterclockwise direction. The system was applied to the lid of buffet ware, which moved up by external force and moved down by gravitational force. However, design conditions which included a rotation angle of the hinge of more than 80 degrees and a closing time of more than 20 seconds were required when the lid of the buffet ware closed due to gravitational force. The design safety of the friction hinge body connected to the lid of the buffet ware from the hinge system was checked on the basis of structural, fatigue and thermal analyses. The material of the shaft, cap and flange among the hinge elements was changed to polyethylene from steel to reduce the weight of the friction hinge system. An injection molding simulation was performed and injection molds of the shaft, cap and flange were created. The weight of the hinge system was decreased from 805g to 219g.

• 한국구조물진단유지관리공학회 논문집
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• 제6권3호
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• pp.167-175
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• 2002

In this paper, an analytical model is proposed for analyzing the hysteretic behavior of RC beam with relocated plastic hinge region under load reversals. The plastic hinge is modeled not to be concentrated on a point but to be distributed on a finite size in beam. This is based on the assumption that the plastic hinge is formed over a certain region, in which the curvature varies. Tangential matrix is reformed using stiffness coefficients including variales such as the length and location of plastic hinge region. In order to construct the hysteretic rule of hinge, modified Takeda rule is also proposed on the base of regression analysis for the previous test results. Previous specimens are analyzed using the proposed model and the result is compared with test result. On the result of the comparison, it was shown that the hysteretic behavior of beams with different location of plastic hinge region could be prediced using the proposed analytical process.

• Journal of Korean Neurosurgical Society
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• 제59권4호
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• pp.368-373
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• 2016

Objective : Delayed hinge fracture (HF) that develops after cervical open door laminoplasty can be a source of postoperative complications such as axial pain. However, risk factors related to this complication remain unclear. We performed a retrospective clinical series to determine risk factors for delayed HF following plate-only open-door cervical laminoplasty. Methods : Patients who underwent plate-only open-door laminoplasty and had available postoperative computed tomography (CT) scans (80 patients with 270 laminae) were enrolled. Hinge status, hinge gutter location, open location, hinge width, number of screws used, operation level, and open angle were observed in the CT to determine radiographic outcome. Demographic data were collected as well. Radiographic and clinical parameters were analyzed using univariate and multivariate logistic regression analysis to determine the risk factors for HF. Results : Univariate logistic regression analysis results indicated poor initial hinge status, medially placed hinge gutter, double screw fixation on the elevated lamina, upper surgical level, and wide open angle as predictors for HF (p<0.05). Initial hinge status seemed to be the most powerful risk factor for HF (p=0.000) and thus was collinear with other variables. Therefore, multivariate logistic regression analysis was performed excluding initial hinge status, and the results indicated that medially placed hinge gutter, double screw fixation on the elevated lamina, and upper surgical level were risk factors for HF after adjustment for other confounding factors. Conclusion : To prevent HF and to draw a successful postoperative outcome after cervical laminoplasty, surgical and clinical precautions should be considered.