• 제목/요약/키워드: Rotation-based method

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Effects of the Instrument Pilates Exercise Based on the Schroth Exercise on the Cobb's Angle, Angle of Trunk Rotation and Low Back Pain in Patients with Idiopathic Scoliosis: A Single Subject Study

  • Song, Ki Yeon;Baek, Ki Hyun;Lim, Mi Soo;Lim, Hyoung-won
    • The Journal of Korean Physical Therapy
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    • 제33권2호
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    • pp.97-105
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    • 2021
  • Purpose: This study examined the effects of the application of Schroth exercise-based instrument Pilates exercise on the Cobb's angle, angle of trunk rotation, and low back pain of female patients with idiopathic scoliosis. Methods: Three patients with idiopathic scoliosis at a Cobb's angle of 20° or more participated in this study. Among the single-subject experimental research designs, a reversal (ABA) design was performed. In particular, Schroth exercise-based instrument, Pilates exercise, was performed for 10 weeks, consisting of five weeks between the baseline and intervention one period and five weeks between the intervention 1 and intervention 2 periods, and then followed up for five weeks. Results: After the Schroth exercise-based instrument, Pilates exercise, was applied, the Cobb's angle and the angle of trunk rotation decreased compared to the baseline in all subjects, and the follow-up period also showed a continuous decline. After Pilates exercise was performed, low back pain in subjects 1 and 2 was decreased in the intervention 1 period compared to the baseline. The level of low back pain in the intervention 2 period increased compared to the intervention 1 period, but a reduction was noted in the follow-up period. The low back pain in the subject was decreased in all intervention periods and the follow-up period. Conclusion: Schroth exercise-based Pilates exercise improves the Cobb's angle and the angle of trunk rotation for female patients with idiopathic scoliosis in their teens and 20s, and an effective intervention method is proposed for low back pain.

Immediate Effects of Upper Trapezius Stretching in More and Less Tensed Positions on the Range of Neck Rotation in Patients With Unilateral Neck Pain

  • Park, Kyue-Nam;Ha, Sung-Min;Kim, Si-Hyun;Kwon, Oh-Yun
    • 한국전문물리치료학회지
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    • 제20권1호
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    • pp.47-54
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    • 2013
  • The purpose of this study was to compare the immediate effects of upper trapezius muscle stretching in more tensed position (MTP) and less tensed position (LTP) on the change of range of motion (ROM) for neck rotation, and the ROM for conjunct neck motions at end-range of neck rotation toward the painful side in patients with unilateral neck pain. Eighteen patients with unilateral neck pain were recruited for the study's MTP group, and 18 age-, weight- and gender-matched patients with unilateral neck pain were recruited for LTP group. The ROM changes in active neck primary and conjunct motions were measured using a cervical ROM inclinometer in the sitting position. Our results showed that both upper trapezius stretching method in MTP and LTP were significantly effective in increasing the ROM of neck rotation toward painful side in patients with unilateral neck pain. However, a significantly greater increase in the ROM for neck rotation and a further decrease in conjunct neck extension during neck rotation toward the painful side were shown in MTP group, compared to LTP group. The upper trapezius stretching in MTP is useful in increasing the ROM of neck rotation and decreasing the range of conjunct neck extension during neck rotation toward the painful side in patients with unilateral neck pain.

잡음과 회전에 강인한 SIFT 기반 PCB 영상 정렬 알고리즘 개발 (Robust PCB Image Alignment using SIFT)

  • 김준철;최학남;박은수;최효훈;김학일
    • 제어로봇시스템학회논문지
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    • 제16권7호
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    • pp.695-702
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    • 2010
  • This paper presents an image alignment algorithm for application of AOI (Automatic Optical Inspection) based on SIFT. Since the correspondences result using SIFT descriptor have many wrong points for aligning, this paper modified and classified those points by five measures called the CCFMR (Cascade Classifier for False Matching Reduction) After reduced the false matching, rotation and translation are estimated by point selection method. Experimental results show that the proposed method has fewer fail matching in comparison to commercial software MIL 8.0, and specially, less than twice with the well-controlled environment’s data sets (such as AOI system). The rotation and translation accuracy is robust than MIL in the noise data sets, but the errors are higher than in a rotation variation data sets although that also meaningful result in the practical system. In addition to, the computational time consumed by the proposed method is four times shorter than that by MIL which increases linearly according to noise.

An Efficient Image Encryption Scheme Based on Quintuple Encryption Using Gumowski-Mira and Tent Maps

  • Hanchinamani, Gururaj;Kulkarni, Linganagouda
    • International Journal of Contents
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    • 제11권4호
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    • pp.56-69
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    • 2015
  • This paper proposes an efficient image encryption scheme based on quintuple encryption using two chaotic maps. The encryption process is realized with quintuple encryption by calling the encrypt(E) and decrypt(D) functions five times with five different keys in the form EDEEE. The decryption process is accomplished in the reverse direction by invoking the encrypt and decrypt functions in the form DDDED. The keys for the quintuple encryption/decryption processes are generated by using a Tent map. The chaotic values for the encrypt/decrypt operations are generated by using a Gumowski-Mira map. The encrypt function E is composed of three stages: permutation, pixel value rotation and diffusion. The permutation stage scrambles all the rows and columns to chaotically generated positions. This stage reduces the correlation radically among the neighboring pixels. The pixel value rotation stage circularly rotates all the pixels either left or right, and the amount of rotation is based on chaotic values. The last stage performs the diffusion four times by scanning the image in four different directions: Horizontally, Vertically, Principal diagonally and Secondary diagonally. Each of the four diffusion steps performs the diffusion in two directions (forward and backward) with two previously diffused pixels and two chaotic values. This stage ensures the resistance against the differential attacks. The security and performance of the proposed method is investigated thoroughly by using key space, statistical, differential, entropy and performance analysis. The experimental results confirm that the proposed scheme is computationally fast with security intact.

시간단축 알고리즘을 통한 3D 동영상 구현 (Implementation of 3D Video using Time-Shortening Algorithm)

  • 신진섭;정찬웅
    • 한국인터넷방송통신학회논문지
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    • 제20권6호
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    • pp.123-128
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    • 2020
  • 본 논문에서는 3차원 동영상을 구현하기 위하여 인체에 유해한 방사능 피폭량이 부챗살 형태의 Fan Beam 보다 상대적으로 적은 원추형 Cone Beam CT 시스템을 설계하였다. 설계된 시스템은 X-ray가 조사된 각도에서 획득한 데이터를 영상처리부로 전송하고 영상을 구성하는 계산 속도를 빠르게 하기 위하여 초월함수가 보다 적은 3단계 회전 행렬을 이용하여 3차원 영상을 구현하는 회전 기반법을 사용하였다. 본 연구에서는 3차원 영상을 구성하는 시간단축을 통해 초당 3~5장의 영상을 얻음으로써 3차원 동영상을 실시간으로 구현하였으며 기존의 데이터 적층 방법에 비해 본 논문에서 사용한 회전 기반법이 우수함을 증명하였으며 단점 및 해결방법 제시하였다.

Optimization-based Image Watermarking Algorithm Using a Maximum-Likelihood Decoding Scheme in the Complex Wavelet Domain

  • Liu, Jinhua;Rao, Yunbo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권1호
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    • pp.452-472
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    • 2019
  • Most existing wavelet-based multiplicative watermarking methods are affected by geometric attacks to a certain extent. A serious limitation of wavelet-based multiplicative watermarking is its sensitivity to rotation, scaling, and translation. In this study, we propose an image watermarking method by using dual-tree complex wavelet transform with a multi-objective optimization approach. We embed the watermark information into an image region with a high entropy value via a multiplicative strategy. The major contribution of this work is that the trade-off between imperceptibility and robustness is simply solved by using the multi-objective optimization approach, which applies the watermark error probability and an image quality metric to establish a multi-objective optimization function. In this manner, the optimal embedding factor obtained by solving the multi-objective function effectively controls watermark strength. For watermark decoding, we adopt a maximum likelihood decision criterion. Finally, we evaluate the performance of the proposed method by conducting simulations on benchmark test images. Experiment results demonstrate the imperceptibility of the proposed method and its robustness against various attacks, including additive white Gaussian noise, JPEG compression, scaling, rotation, and combined attacks.

Study of Mechanism of Counter-rotating Turbine Increasing Two-Stage Turbine System Efficiency

  • Liu, Yanbin;Zhuge, Weilin;Zheng, Xinqian;Zhang, Yangjun;Zhang, Shuyong;Zhang, Junyue
    • International Journal of Fluid Machinery and Systems
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    • 제6권3호
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    • pp.160-169
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    • 2013
  • Two-stage turbocharging is an important way to raise engine power density, to realize energy saving and emission reducing. At present, turbine matching of two-stage turbocharger is based on MAP of turbine. The matching method does not take the effect of turbines' interaction into consideration, assuming that flow at high pressure turbine outlet and low pressure turbine inlet is uniform. Actually, there is swirl flow at outlet of high pressure turbine, and the swirl flow will influence performance of low pressure turbine which influencing performance of engine further. Three-dimension models of turbines with two-stage turbocharger were built in this paper. Based on the turbine models, mechanism of swirl flow at high pressure turbine outlet influencing low pressure turbine performance was studied and a two-stage radial counter-rotation turbine system was raised. Mechanisms of the influence of counter-rotation turbine system acting on low-pressure turbine were studied using simulation method. The research result proved that in condition of small turbine flow rate corresponding to engine low-speed working condition, counter-rotation turbine system can effectively decrease the influence of swirl flow at high pressure turbine outlet imposing on low pressure turbine and increases efficiency of the low-pressure turbine, furthermore increases the low-speed performance of the engine.

방향 회전에 불변한 얼굴 영역 분할과 LBP를 이용한 얼굴 검출 (Face Detection using Orientation(In-Plane Rotation) Invariant Facial Region Segmentation and Local Binary Patterns(LBP))

  • 이희재;김하영;이다빛;이상국
    • 정보과학회 논문지
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    • 제44권7호
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    • pp.692-702
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    • 2017
  • LBP기반 특징점 기술자를 이용한 얼굴검출은 얼굴의 형태정보 및 눈, 코, 입과 같은 얼굴 요소들 간 공간정보를 표현할 수 없는 문제가 있다. 이러한 문제를 해결하기 위해 선행 연구들은 얼굴 영상을 다수개의 사각형 부분영역들로 분할하였다. 하지만, 연구마다 서로 다른 개수와 크기로 부분 영역을 분할하였기 때문에 실험에 사용하는 데이터베이스에 적합한 부분 영역의 분할 기준이 모호하며, 부분 영역의 수에 비례하여 LBP 히스토그램 차원이 증가되고, 부분 영역의 개수가 증가함에 따라 얼굴의 방향 회전에 대한 민감도가 크게 증가한다. 본 논문은 LBP기반 특징점 기술자의 방향 회전 문제와 특징점 차원의 수 문제를 해결할 수 있는 새로운 부분 영역 분할 방법을 제안한다. 실험 결과, 제안하는 방법은 방향 회전된 단일 얼굴 영상에서 99.0278%의 검출 정확도를 보였다.

Moment-rotation relationship of hollow-section beam-to-column steel joints with extended end-plates

  • Wang, Jia;Zhu, Haiming;Uy, Brian;Patel, Vipulkumar;Aslani, Farhad;Li, Dongxu
    • Steel and Composite Structures
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    • 제29권6호
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    • pp.717-734
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    • 2018
  • This paper presents the flexural performance of steel beam-to-column joints composed of hollow structural section beams and columns. A finite element (FE) model was developed incorporating geometrical and material nonlinearities to evaluate the behaviour of joints subjected to bending moments. The numerical outcomes were validated with experimental results and compared with EN1993-1-8. The demountability of the structure was discussed based on the tested specimen. A parametric analysis was carried out to investigate the effects of steel yield strength, end-plate thickness, beam thickness, column wall thickness, bolt diameter, number of bolts and location. Consequently, an analytical model was derived based on the component method to predict the moment-rotation relationships for the sub-assemblies with extended end-plates. The accuracy of the proposed model was calibrated by the experimental and numerical results. It is found that the FE model is fairly reliable to predict the initial stiffness and moment capacity of the joints, while EN1993-1-8 overestimates the initial stiffness extensively. The beam-to-column joints are shown to be demountable and reusable with a moment up to 53% of the ultimate moment capacity. The end-plate thickness and column wall thickness have a significant influence on the joint behaviour, and the layout of double bolt-rows in tension is recommended for joints with extended end-plates. The derived analytical model is capable of predicting the moment-rotation relationship of the structure.

Fuzzy Mean Method with Bispectral Features for Robust 2D Shape Classification

  • Woo, Young-Woon;Han, Soo-Whan
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 1999년도 추계학술대회-지능형 정보기술과 미래조직 Information Technology and Future Organization
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    • pp.313-320
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    • 1999
  • In this paper, a translation, rotation and scale invariant system for the classification of closed 2D images using the bispectrum of a contour sequence and the weighted fuzzy mean method is derived and compared with the classification process using one of the competitive neural algorithm, called a LVQ(Learning Vector Quantization). The bispectrun based on third order cumulants is applied to the contour sequences of the images to extract fifteen feature vectors for each planar image. These bispectral feature vectors, which are invariant to shape translation, rotation and scale transformation, can be used to represent two-dimensional planar images and are fed into an classifier using weighted fuzzy mean method. The experimental processes with eight different shapes of aircraft images are presented to illustrate the high performance of the proposed classifier.

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