• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2323-2329
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• 2008

Advances in wireless communication and hardware technology have made it possible to manufacture high-performance tiny sensor nodes. More recently, the availability of inexpensive cameras modules that are able to capture multimedia data from the environment has fostered the development of Wireless Multimedia Sensor Networks(WMSNs). WMSN supplements the a advanced technique that senses, transmits, and processes the multimedia contents upon the text based traditional wireless sensor network. Since the amount of data which the multimedia contents have, is significantly larger than that of text based data, multimedia contents require lots of computing power and high network bandwidth. To process the multimedia contents on the wireless sensor node which has very limited computing power and energy, a technique for WMSN should take account of computing resource and efficient transmission. In the paper, we propose a new image compression technique YWCE for efficient compression and transmission of image data in WMSN. YWCE introduces 4 type of technique for motion estimation and compensation based on the Resolution Scalability of Wavelet. Experimental result shows that YWCE has high compression performance with different set of 4 type.

• Journal of the Korean Arthroscopy Society
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• v.1 no.1
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• pp.66-71
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• 1997

The all inside anterior cruciate ligament reconstruction technique places an anterior ligament substitutes within two bony sockets rather than hone tunnel. This approach is accomplished through arthroscopic three portal which avoids the surgical exposure and morbidity associated with creating traditional bone tunnel. This technique has several distinct advantages when compared with the traditional ACL reconstruction through the bone tunnels. It offers the surgeon a less morbid method for ACL reconstruction that positions an ACL substitute at the anatomic attachment sites of the original ACL with two bone sockets, obviating the need for traditional bone tunnels. Graft fixation at or near the anatomic attachment points of the original ACL minimizes creep with early range of motion and reduces the abrasive 'wind-shield wipe' motion of the graft which occur with bone plugs positioned inside bone tunnels. The sagittal posterior angle to the tibial socket increases fixation strength to pullout with anterior translation force for the tibia on the femur. This technique is not graft specific and can accomodate any graft in which graft length can be customized to the intraarticular native ACL length.

• PNF and Movement
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• v.14 no.2
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• pp.139-147
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• 2016

Purpose: This study examined whether a single application of a lumbar flexion muscle energy technique (MET) could significantly influence pain, functional status, and range of motion in chronic back pain patients with restricted active trunk flexion. Methods: Twenty volunteers were randomly assigned to either a control group or an experimental group. Ten subjects in the control group received no treatment. Ten subjects in the experimental group received five sessions with the muscle energy technique, five times per week for two weeks. Outcomes were measured before and after two weeks of treatment in both groups. Pain intensity was assessed using a visual analogue scale (VAS). Range of motion was measured using the sit-and-reach test (SRT). Functional disability levels were assessed using the Korean version of the Oswestry Disability Index (KODI). Results: The experimental group showed a significant difference in VAS, KODI, and SRT between pre- and post-treatment (p < .05), while the control group showed no significant changes. The changes in VAS, ODI, and SRT were statistically significant between the groups pre- and post-treatment (p < .05). Conclusion: This muscle energy technique is clinically effective for chronic low back pain patients.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.7C
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• pp.726-732
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• 2003

The paper proposes a motion estimation (ME) technique to reduce computational complexity. It is achieved by skipping ME process for macro-blocks decided to be in no need of the operation. Thus, it is called ME skipping technique(MEST). In general, the ME is composed of integer pixel precision ME (IME) followed by half pixel precision ME (HME). The MEST is performed just before an IME process and makes a decision on skipping the IME process according to a criterion based on ME errors of adjacent macro-blocks (MBs) already encoded. When the IME process for a MB is decided to be skipped, which is called ME skip mode, the IME process is skipped and the integer pixel precision motion vector of the MB is just replaced by a predicted vector and used as the input of HME. On the other hands, the IME processes for MBs in ME non-skip mode are not skipped but normally performed. Accordingly, the MEST is very effective to reduce computational complexity when MBs in ME skip mode is abundant. In addition, when the MEST is applied to video encoder, it contributes to more accurate rate control and more robusaess for channel errors. It is experimentally shown that the MEST has the above advantages while maintaining good reconstructed image quality.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.6
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• pp.119-126
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• 1998

In this paper, we proposed two new methods of half-pel accuracy motion estimation using spatial correlation of half-pel accuracy motion vectors and stochastic characteristics between pixel accuracy motion vectors and half-pel accuracy motion vectors. We confirmed two facts : One is that the probability of having same half-pel accuracy motion vectors with neighboring blocks is high when having same pixel accuracy motion vectors. And the other is that there is high correlation between neighboring half-pel positions. These new half-pel motion estimation technique are shown to decrease the bit rates for vector coding and computational complexity with similar PSNR.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.6 s.150
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• pp.631-637
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• 2006

This paper presents a numerical method to solve the ship motion coupled with internal fluid flow. Physically the internal fluid motion is coupled with the ship motion. Hitherto the previous numerical results of the coupled motion predict only the general tendency with experiments. The main reason of inaccuracy is that the coupled dynamics of ship motion and internal water motion is not accurately accounted. In this study CFD technique based on VOF is employed for the accurate analysis of flooding water motion. Some cases of the 24th ITTC stability committee's benchmark.study for tanker with internal fluid are analyzed by coupling the ship motion and sloshing dynamics. The calculated ship motion is compared with the experimental result to validate the coupled scheme and is in agreement with the experimental result.

• Journal of radiological science and technology
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• v.16 no.2
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• pp.19-26
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• 1993

Magnetic Resonance Image represents three-dimensional diagnostic imaging technique using both nuclear magnetic resonance phenomenon and computer. Compared with computed tomography (CT), MRI have advantages harmless to patient's body, three-dimensional image with high resolution and disadvantages long data acquisition time because of long T1 relaxation time, relatively low signal to noise ratio, high cost of setting, also. As physiologic motion of tissue results in motion ghost in MRI, high 2.0Tesla make improve low signal to noise ratio. This study have aim to improve image quality with controling motion ghost of tissue. Supposing a moving pixel in constant frequency, one pixel make two ghosts which are same size and different anti-phase. So, this study will show adjust parameter on locational control of motion ghost. Author made moving phantom replaced by respiratory movement of human, researched change of motion frequency, FOV by location shift, and them decided optimal FOV (field of view). The results are as follows: 1. The frequency content of the motion determines how far the image always appear in phase-encoding direction, the morphology of the ghost image is characteristic of the direction of the motion and its amplitude. 2. Double FOV of fixed signal object for locational control of motion ghost is recommended. Decreasement of spatial resolution by increasing FOV can compensate on increasing of matrix in spite of scan time increasement.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.498-502
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• 2004

In a link-motion mechanism, numerous links are interconnected and each link executes a constrained motion at a high speed. Due to the complicated constrained motions of the constituent links, dynamic unbalance forces and moments are generated and transmitted to the main frame. Therefore unwanted vibration is produced. This degrades productivity and precise work. Based on constrained multi-body dynamics, the kinematic analysis is carried out to enable design changes to be made. This will provide the fundamental information for significantly reducing dynamic unbalance forces and moments which are transmitted to the main frame. In this work, a link-motion punch press is selected as an example of a link-motion mechanism. To calculate the mass and inertia properties of every link comprising a link-motion punch press, 3-dimensional CAD software is utilized. The main issue in this work is to eliminate the first-order unbalance force and moment in a link-motion punch press. The mass, moment of inertia link length, location of the mass center in each link have a great impact on the degree of dynamic balancing which can be achieved maximally. Achieving good dynamic balancing in a link motion punch press is quite essential fur reliable operation at high speed.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.1075-1078
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• 1999

In this paper, we propose a hybrid watermarking algorithm for MPEG bitstream. Hybrid watermarking technique uses Spread Spectrum technique for I-frame and Motion Vector technique for P, B-frame. Thus, it enables all MPEG frame to be watermarked. By applying above technique, it is possible not only to protect intellectual property right but also to be robust to all kinds of attacks. And this scheme requires partial decoding of MPEG bitstream, so it can be applied to real time watermarking applications.

• Korean Journal of Computational Design and Engineering
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• v.17 no.6
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• pp.443-455
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• 2012

The configuration of a musculoskeletal (MS) system is closely related to the individual motions of the human body. Many researches have been focused on evaluating the associations between the MS configuration and the individual motion using patient-specific MS models, but it still remains a challenging issue to accurately predict the motion by differed configurations of the MS system. The main objective of this paper is to predict the changes of a patient-specific gait by altering the geometric parameters of the hip joint using function-based morphing method (FBM). FBM is suitable for motion analysis since this method provide a robust way to morph a MS model while preserving the biomechanical functions of the bones. Computed-muscle control technique is used to calculate the muscle excitations to reproduce the targeted motion within a digital MS model without the motion-captured data. We applied this approach to a patient who has an abnormal gait pattern. Results showed that the femoral neck length and the angle significantly affect to the motion especially for the hip abduction angle during gait, and that this approach is suitable for gait prediction.