• Smart Structures and Systems
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• v.5 no.2
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• pp.153-171
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• 2009

In this paper, the analytical fault detection and diagnosis (FDD) is presented using model-based and signal-based methodology with wavelet analysis on signals obtained from sensors and sensor networks. In the model-based FDD, we present the modeling of contact interface found in soft materials, including the biomedical contacts. Fingerprint analysis and signal-based FDD are also presented with an experimental framework consisting of a mechanical pneumatic system typically found in manufacturing automation. This diagnosis system focuses on the signal-based approach which employs multi-resolution wavelet decomposition of various sensor signals such as pressure, flow rate, etc., to determine leak configuration. Pattern recognition technique and analytical vectorized maps are developed to diagnose an unknown leakage based on the established FDD information using the affine mapping. Experimental studies and analysis are presented to illustrate the FDD methodology. Both model-based and wavelet-based FDD applied in contact interface and manufacturing automation have implication towards better quality of life by applying theory and practice to understand how effective diagnosis can be made using intelligent FDD. As an illustration, a model-based contact surface technology an benefit the diabetes with the detection of abnormal contact patterns that may result in ulceration if not detected and treated in time, thus, improving the quality of life of the patients. Ultimately, effective diagnosis using FDD with wavelet analysis, whether it is employed in biomedical applications or manufacturing automation, can have impacts on improving our quality of life.

• Journal of Periodontal and Implant Science
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• v.36 no.4
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• pp.817-827
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• 2006

Purpose : This study was designed 1) to compare the perception of dental professionals and lay people with respect to minor variations in maxillary anterior tooth size and alignment and their relation to the surrounding soft tissues, and 2) to evaluate the normal tooth-gingiva topographical relationships in periodontally healthy young subjects, Materials and methods : Maxillary anterior teeth were intentionally diagrammed in varying degree of deviation with respect to one of three common anterior esthetic discrepancies including variations in crown length, shape of gingival margin, and length of interproximal contact, 17 images were generated to be preferentially selected by 2 groups consisting of dental professionals and lay people (total of 740). Smiling photographs of 120 dental students who had healthy periodontium were taken and the photographic images were analyzed to be classified as 17 kinds of altered image groups. Results : The results demonstrated noticeable difference between the varying levels of discrepancy. Both group preferred gingival margin of lateral incisor to be 0.5mm lower than that of central incisor. Lay people preferred the gingival margin shape that has 2/9 horizontal component of the crown width, while dental professionals preferred the gingival margin shape that has 1/9 horizontal component of the crown width. Lay people preferred longer length of the interproximal contact (two thirds of the crown length), whereas dental professionals preferred shorter length of the interproximal contact (half of the crown length). Photographic analysis of normal esthetic gingival topography revealed 2/9 horizontal component and short length of the interproximal contact which was of the hybrid nature of the preferences shared by lay people and dental professionals. Conclusion: The results of this study show that dental professionals and lay people demonstrated significant difference in their preference of dental esthetic components, which may then influence the decision making process by dental professionals with respect to designing the anterior esthetic gingival line.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.31 no.1
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• pp.27-30
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• 2020

Among lesions in the larynx, laryngeal contact granuloma due to persistent tissue irritation can typically be attributed to endotracheal intubation, vocal abuse, or gastro-esophageal reflux disease. Treatment typically includes voice therapy, lifestyle changes and use of anti-reflux medication. Microsurgical removal is only indicated in cases of severe dyspnea due to mass size. Foreign body granuloma is a response of to any foreign material in the tissue. Foreign body granulomas are sometimes misdiagnosed as soft tissue tumors when the causative foreign body is not initially found. Delayed treatment of these foreign bodies may cause complications. We present a case of larynx granuloma due to impacted foreign body, probably fish bone, in the larynx that mimicked contact granuloma. We initially used anti-reflux medication, but to no avail. The laryngeal mass, observed through laryngoscopy, showed no improvement and therefore necessitated a proper pathologic diagnosis. We were able to successfully treat it via trans-oral laser CO2 microsurgery before any complications developed.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.4
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• pp.55-69
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• 2007

The purpose of this study was to perform a clinical test using ez NANOsence II RGP contact lenses for the effects of visual acuity and cornea on subjects with abnormal refraction status. One hundred twenty one adults (twenty nine males, ninety two females, range = 17 to 43, mean = 22.86) were recorded. The subject's history including, the symptoms from previous lens wear, were studied. The subjects were observed, both pre and post lens wear, for any symptoms and signs of change of the eye. The Visual acuity and the binocular status were tested at the far distance using the contact lens. The refraction test was performed on the naked eye using the objective method (Topcon KR-8100, Japan). The Stereopsis test was performed at the near distance after contact lens wear by the Titmus fly (Stereo Optical Co., U.S.A) and TNO (TECH, The netherlands). The contrast sensitivity diagnosis was performed at 1m distance after contact lens wear by the contrast sensitivity chart (pelli-Robertson, USA). The corneal topography was analyzed on the naked eye after lens wear by ORB scan (Bausch Lomb, U.S.A.). The ultra structure of surface on the contact lens was observed using SEM (JMS-5800, Japan). The chemical component's of the contact lens was analyzed by EDS program. The results of this study were as follows: 1. The longer of contact lens wear period, The subjects have acquired the most improved visual function. 2. Subjects had experienced few side effects wearing the contact lenses. 3. The lenses were easy to use by the subjects. 4. The longer of contact lens wear period, the power of cornea had more decrease. but the base curve of cornea had more increase and corneal astigmatism was decrease (p<0.01). Also, the thickness of corneal center was few decrease. 5. Longer periods of using the contact lens showed stereopsis and contrast sensitivity at more normal values. 6 The corneal topographical after lens wear showed most subjects with similar morphology for different wear periods. 7. The surface ultrastructure of the new and used contact lens was the similar fine shape. 8. The chemical component's of in the new and used contact appeared to have similar results. In conclusion, this study showed that the surface ultrastructure and chemical component's of the new and used contact lens are similar. In addition, the subjects had improved the quality of vision and few experienced any side effects during long periods of contact lens wear. Also they have decrease of corneal astigmatism during the long period of lens wear. Our test has showed that the chemical composition and fine structure of contact lens have related to the visual function on contact lens wearer. In this paper, we suggested that ez NANOsence II RGP contact lenses had a moderate effect for correcting vision of abnormal refraction eye.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.145-151
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• 2014

Purpose: The material properties of contact lenses were measured by varying the amounts of an initiator and a cross-linking agent that are the basis for the manufacture of contact lenses, and the drug delivery effects depending on the material properties of contact lenses were compared. Methods: Contact lens samples were manufactured using HEMA by varying the concentration of the cross-linking agent and the initiator. To investigate the changes in physical characteristics depending on the material properties, the results of the experiments on the amount of drug elution, water content, refractive index, and the amount of protein adsorption were compared. Results: For the contact lenses manufactured by varying the amount of the initiator, the water content hardly changed, and the refractive index also hardly changed. The amount of drug elution was not much affected by the changes in the initiator, but the amount of elution increased as the water content increased. The amount of protein adsorption was hardly affected by the changes in the initiator, but the amount of adsorption increased as the water content decreased. Conclusions: The changes in the properties were hardly affected by the changes in the amount of the initiator, but were significantly affected by the changes in the amount of the cross-linking agent. As the amount of the cross-linking agent increased, the water content decreased, while the refractive index increased. Also, when the water content increased, the amount of drug elution increased, while the amount of protein adsorption decreased.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.117-124
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• 2015

Purpose: The purpose of this study was to compare the accommodative function of young adult in their 20s wearing monovision, modified monovision, and aspheric multifocal contact lenses at near task. Methods: Thirty young adults ($23.53{\pm}2.37years$) were fitted with monovision, modified monovision (the application of single vision contact lenses and center-near low addition aspheric multifocal contact lenses), and aspheric center-near multifocal contact lenses. After wearing these modalities during a week for adaption, and after watching visual display at computer for inducing accommodative pressure for 1 hour. The following assessments of accommodative function were made: contrast visual acuity (VA) at distance and near; accommodative response; near accommodative facility; and negative relative accommodation (NRA)/positive relative accommodation (PRA). All measurements were carried out binocularly. Results: In binocular distance VA with contrast of 10%, monovision was the worst among the four modalities (p=0.005). In accommodative response at 1 m (1.00 D), monovision was the lowest (p<0.05) and accommodative response at 40 cm (2.50 D) with monovision was lower than that of modified monovision and multifocal contact lens (p<0.05). We also found that there were no significant differences in accommodative facility and NRA/PRA among the four modalities. Conclusions: In young adult (20s), monovision with low add reduced the accommodative response at near task, however, modified monovision and multifocal lens with center-near type did not affect accommodative relaxation.

• Journal of Korean Dental Science
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• v.2 no.2
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• pp.24-30
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• 2009

Two component orthodontic C-implants have been introduced as intermaxillary fixation (IMF) screws in cases of periodontal problems with bone loss, severely damaged teeth, or short roots. This retrospective research sought to investigate the complications and risk factors associated with the failure of two-part C-implants for IMF cases and to show the possible indications compared to one-component mini-implants. The study sample consisted of 46 randomly selected patients who had a total of 203 implants. Pearson chi-square tests of independence were used to test for associations among categorical variables. At least 19 of the total 203 implants failed (9.3%). There was no significant difference in implant failure due to gender, oral hygiene, and placement, although a significant difference due to soft tissue characteristics and root contact was observed. The two-component design of the mini-implant is reliable for difficult IMF cases. Note, however, that the factors influencing implant failure were found to be age, root damage, and condition of soft tissues.

• Clean Technology
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• v.22 no.3
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• pp.203-207
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• 2016

Here, we report a novel fabrication technique for patchable organic lasing sheet based on non-volatile liquid organic semiconductors and freestanding polymeric film with high flexibility and patchability. For this work, we have fabricated the second-order DFB grating structure, which leads to surface emission, embedded in the freestanding polymeric film. Using an ultra-violet (UV) curable polyurethaneacrylate (PUA) mixture, the periodic DFB grating structure can be easily prepared on the freestanding polymeric film via a simple UV curing process. Due to unsaturated acrylate remained in the PUA mixture after UV curing, the freestanding PUA film provides adhesive properties, which enable mounting of the patchable organic lasing sheet onto non-flat surfaces with conformal contact. To achieve laser actions in the freestanding resonator structure, a composite material of liquid 9-(2-ethylhexyl)carbazole (EHCz) and organic laser dyes was used as the laser medium. Since the degraded active materials can be easily refreshed by a simple injection of the liquid composite, such a non-volatile liquid organic semiconducting medium has degradation-free and recyclable characteristics in addition to other strong advantages including tunable optoelectronic responses, solvent-free processing, and ultimate mechanical flexibility and uniformity. Lasing properties of the patchable organic lasing sheet were also investigated after mounting onto non-flat surfaces, showing a mechanical tunability of laser emission under variable surface curvature. It is anticipated that these results will be applied to the development of various patchable optoelectronic applications for light-emitting displays, sensors and data communications.

• Archives of Reconstructive Microsurgery
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• v.15 no.2
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• pp.111-116
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• 2006

An infection after total knee arthroplasty has many complications such as severe bone defect, skin and soft tissue problems, devastated general condition, so arthrodesis is preferred as treatment option. However, poor bony contact due to severe bone defect and inadequate conditions of the soft tissue often cause nonunion or severe limb shortening after arthrodesis. More over these conditions, it is not easy to choose appropriate fixative devices. In these situations, the arthrodesis using vascularized fibular graft can be the solution. Vascularized fibular graft (VFG) can playa role as a suitable material for the treatment of bone defects. And VFG can overcome poor blood circulation caused by scar tissues, and can be relatively more durable and adequate length. In the long term, VFG can be hypertrophied by weight bearing, and will give mechanical stablility. The purpose of the paper is to report the successful results of arthrodesis using VFG in a patient who got extensive bone defect after failed revision total knee arthroplasty with infection.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.81-88
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• 2005

This paper attempts to derive the dynamic model of handling tasks in finger robot which grasps stable and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, the roblems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. The effect of geometric constraints of area-contacts between the link's end-effector and the object is analyzed and the model based on the differential-algebraic equations is presented. In this paper, the control method for dynamic stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation and the experiment that the control system gives the performance improvement in the dynamic stable grasping and nimble manipulating of the dual fingers robot with soft tips.