• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.91-97
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• 2005

Bones are dynamic structures, being supported by muscles, tendons, and ligaments. When some or all the structures are disturbed i.e. in fractures, the alignment of the bone in respect to the rest of the body is deranged. This gives rise to axial as well as rotational deformity in three dimensional planes. The correct alignment and position of the long bones are to be maintained to heal the bone in the best possible anatomical and functional position. The objective of this research is to address the problems in the current practice involving surgeon, assistant, fluoroscopy and crude mechanical means and to see if a robotic solution exists to solve the problems of manipulating and reducing long bone fractures. This paper presents various design aspects of the proposed surgeon-instructed, image-guided and robotic system including the system design specification, robot design and analysis, motion control and implementation, and x-ray image processing and incorporation in CAD environment.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.37-43
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• 2002

In this paper, we analyse and present mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure angular velocities about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the rotation of the gyroscope main body. The equations of motion, the response to angular velocities, and the relationships between the natural modes of vibration are derived and compared with the previous studies for the design of a micro three-axis ring gyroscope.

• Journal of Korean Neurosurgical Society
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• 제42권6호
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• pp.487-489
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• 2007

Forestier's disease is a systemic rheumatological abnormality in which exuberant ossification occurs along ligaments throughout the body, but most notably the anterior longitudinal ligament of the spine. This disease is usually asymptomatic; however dysphagia, dyspnea, and peripheral nerve entrapment have all been documented in association with the disorder. We report a rare case of catastrophic neurologic damage caused by Forestier's disease accompanying ossification of the posterior longitudinal ligament.

• 대한치과교정학회지
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• 제11권2호
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• pp.65-70
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• 1981

In the present study orthodontic force was applied to the molars of control group and experimental group treated with the lathyrogen beta-aminopropionitrile (BAPN). Observation resulted in the following conclusions : 1) New alveolar bone formation in response to orthodontic force in BAPN-treated rats exceeded corresponding bone formation in control of cup when measured at two tension sites in the periodontal ligament. 2) BAPN administration produced disorganization of the collagenous fibers of the periodontium of experimental group. Multiple eosinophilic cell-free areas were found distributed throughout the radicular portions of affected periodontal ligaments. 3) The areas of periodontium surrounding orthodontically treated teeth exhibited relatively normal organization under these conditions, while the periodontium of adjacent nonorthodontically treated teeth was disorganized. 4) The present results suggest that the typical histologic response to orthodontic force application can occur in the presence of a chemically and physically altered periodontium.

• 대한족부족관절학회지
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• 제24권1호
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• pp.1-8
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• 2020

Acute ankle sprain is the most common injury in the lower extremities, and approximately 10% to 40% of acute lateral ankle ligament injury causes chronic pain or instability. For chronic symptoms lasting after an acute sprain, the possibility of joint damage, such as bony structures, ligaments, cartilage, and nerves around the ankle joint, should be considered. Patients with chronic lateral ankle instability usually complain of repeated sprains or giving way sensations. There has been steady progress in the treatment options until recently, however new treatments are still being attempted. This paper describes the causes, diagnosis, and recent trends in the conservative and operative treatment of chronic lateral ankle instability.

• 한국세라믹학회지
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• 제31권10호
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• pp.1099-1106
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• 1994

It is suggested that the microstructural toughening process in the initial rising portion of R-curves observed in polycrystalline alumina should be different from the grain bridging mechanism identified in the long crack regime. Microcracking in the advancing crack front seems to be a prerequisite for the development of unbroken bridging ligaments behind the crack tip. In order to test such a proposition, attempts were made to identify experimentally the presence of microcracks in the frontal zone of propagating cracks. In-situ observation is made of crack growth in a miniature double cantilever beam specimen of a average grain size of 10 ${\mu}{\textrm}{m}$ alumina. Presence of a few microcracks was identified in front of crack tip on the propagating crack plane. The R-curves were re-evaluated based on the observation.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.701-704
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• 2003

Scoliosis is a complex musculoskeletal dieses requiring 3-D treatment with surgical instrumentation. Conventional corrective surgery for scoliosis was done based on empirical knowledge without information of the optimum position and operative procedure. Frequently, post operative change of rib hump increase and shoulder level imbalance caused serious problems in the view of cosmetics. To investigate the effect of correction surgery, a reconstructed 3-D finite element model for King-Moe type V was developed. Vertebrae, clavicle and other bony element were represented using rigid bodies. Kinematic joints and nonlinear bar elements used to represent the intervertebral disc and ligaments according to reported experimental data. With this model, optimization technique was also applied in order to define the optimal magnitudes of correction. The optimization procedure corrected the scoliotic deformities by reducing the objective function by more than 94%. with an associated reduction of the scoliotic descriptors mainly on the frontal thoracic curve.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.312.1-312
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• 2002

In this paper, we analyse and present mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure rates of turn about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the rotation of the gyroscope main body. (omitted)

• 한국분무공학회지
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• 제2권4호
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• pp.22-28
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• 1997

In this paper an experimental study of a spray created by two impinging jets is presented utilizing a novel two-reference-beam double-pulse holographic technique. Visualization of the overall spray pattern as well as measurements on the size and velocity of the droplets were performed with the special emphasis on the effect of physical properties of liquids. The overall spray pattern clearly revealed the inherent wave nature In the disintegration process of this type of atomization. The structure of liquid elements near the impingement point is indicative of the mechanisms of the disintegration process. Surface tension plays an important role in the droplet size without any noticeable effect on the spray pattern, whereas viscosity affects the structure without any significant effect on the droplet sire. The droplet velocities were not affected by liquid properties.

• Clinics in Shoulder and Elbow
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• 제6권2호
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• pp.115-126
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• 2003

Although painful conditions of varying degrees of severity involving the soft tissues (i .e., muscles, tendons, ligaments, periosteum and peripheral nerves) occur frequently, their underlying pathogenesis is poorly understood. The term peripheral neuropathic pain has recently been suggested to embrace the combination of positive and negative symptoms in patients whose pain is due to pathological changes or dysfunction in peripheral nerves or nerve root. The spinal nerve root, because of its vulnerable position, is very easily prone to injury from pressure, stretch, angulation, and friction. Therefore, not a few of musculoskeletal chronic pains are result of nerve root dysfunction. Neuropathic changes due to nerve root dysfunction are primarily in soft tissue especially muscle, tendon and joint. It shows tenderness over muscle motor points and palpable muscle contracture bands and restricted Joint range. Careful palpation and physical examination is the important tool that, be abne to detect all of these phenomena.