• Korean Journal of Computational Design and Engineering
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• v.11 no.3
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• pp.205-210
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• 2006

Curve tessellation, which generates a sequence of points from a curve, is very important for curves rendering on a computer screen and for NC machining. For the most case the sequence of discrete points is used rather than a continuous curve. This paper deals with a method of tessellation by calculating the maximal deviation of a curve. The maximal deviation condition is introduced to find the point with the maximal chordal deviation on a curve segment. In the previous research a curve tessellation was tried by the subdivision method, that is, a curve is subdivided until the maximal chordal deviation is less than the given tolerance. On the other hand, a curve tessellation by sequential method is tried in this paper, that is, points are generated successively by using the local property of a curve. The sequential method generates relatively much less points than the subdivision method. Besides, the sequential method can generate a sequence of points from a spatial curve by approximation to a planar curve. The proposed method can be applied for high-accuracy curve tessellation and NC tool-path generation.

• Korean Journal of Computational Design and Engineering
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• v.9 no.2
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• pp.158-163
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• 2004

Curve tessellation, which generates a sequence of points from a curve, is very important for curve rendering on a computer screen and for NC machining. For the most case the sequence of discrete points is used rather than a continuous curve. This paper deals with a method of tessellation by calculating the maximal deviation of a curve. The maximal deviation condition is introduced to find the point with the maximal deviation. Our approach has two merits. One is that it guarantees satisfaction of a given tolerance, and the other is that it can be applied in not only a polynomial curve but its offset. Especially the point sequence generated from an original curve can cause over-cutting in NC machining. This problem can be solved by using the point sequence generated from the offset curve. The proposed method can be applied for high-accuracy curve tessellation and NC tool-path generation.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.77.1-77.1
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• 2016

We investigate the properties and detection conditions for the planetary caustic perturbation of close-separation planets. To find the properties of the planetary caustic perturbation, we construct deviation maps by subtracting the single-lensing magnification of the lens star from the planetary lensing magnification for various lensing parameters. We find that each deviation area of the positive and negative perturbations disappears at the same normalized source radius according to a given deviation threshold regardless of mass ratio but disappears at a different normalized source radius according to the separation. We also estimate the upper limit of the normalized source radius to detect the planetary caustic perturbation. We find simple relations between the upper limit of the normalized source radius and the lensing parameters. From the relations, we obtain an analytic condition for the detection limit of the planet, and which show that we can sufficiently discover a planet with the mass of sub-Earth for typical microlensing events. Therefore, we expect to add the number of low-mass planets in the next-generation microlensing experiments and conclude that our detection condition of the planet can be used as a important criteria for maximal planet detections considering the source type and the photometric accuracy.

• Physical Therapy Korea
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• v.27 no.4
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• pp.227-232
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• 2020

Background: Hallux valgus (HV) is a foot deformity developed by mediolateral deviation of the first metatarsophalangeal joint. Although various foot-toe orthoses were used to correct the HV angle, verification of the effects of kinetics variables such as ground reaction force (GRF) through three-dimensional (3D) gait analysis according to the various type of orthoses for HV is insufficient. Objects: This study aimed to investigate the effect of soft and hard types of foot and toe orthoses to correct HV deformity on the GRF in individuals with HV using 3D motion analysis system during walking. Methods: Twenty-six subjects participated in the experiment. Participants had HV angle of more than 15° in both feet. Two force platforms were used to obtain 3D GRF data for both feet and a 3D motion capture system with six infrared cameras was used to measure exact stance phase point such as heel strike or toe off period. Total walk trials of each participant were 8 to 10, the walkway length was 6 m. Two-way repeated measures ANOVA was used to determine the effects of each orthosis condition on the various GRF values. Results: The late anteroposterior maximal force and a first vertical peak force of the GRF showed that the hard type orthosis condition significantly increased GRF compared to the other orthosis conditions (p < 0.05). Conclusion: There were significant effects in GRF values when wearing the hard type foot orthosis. However, the hard type foot orthosis was uncomfortable to wear during walking. Therefore, it is necessary to develop a new foot-toe orthosis that can compensate for these disadvantages.

• The Journal of Pediatrics of Korean Medicine
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• v.12 no.1
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• pp.111-131
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• 1998

1. In oriental medicine, the case of sinusitis can be explained, not only external invasion such as PUNG HAN(wind-cold), PUNG YUL(wind-hot), SHUP YUL(damp-heat), but also functional disorder of internal organ such as spleen(脾), lung(肺), kidney(腎) The western medicine classified the cause of sinusitis as two factors. That is bacterial infection factor-Haemophilus influenza, streptococcus pyogeues, streptococcus pneumonia- and viral infection factor-Rhinovirus, parainfluenza, Echo28, Coxsacki21, Sinusitis is complicated to allergic rhinitis, chronic otitis media purulent, chronic tonsilitis, sinubronchitis. On the condition of nasal septum deformity, turbinates deformity, nasal septum deviation, sinusitis can be developed. the predisposing factors of sinusitis is swimming, air pollution, malnutrition, shortage of immunity.2. According to survey, sinusitis occurred that children from 4 to 12 years old and from 5 to 7 years old occupied 70% 3. From the past history data, they experienced chronic tonsillar hypertropy(20%), otitis media, atopic dermatitis, allergic rhinitis, bronchial asthma, pneumonia, bronchiolitis, chronic sore throat, urticaria, milk allergy in sequence. 4. the symptoms of sinusitis is nasal obstruction, postnasal dripping, purulunt(yellow)or white discharge, cough, nose bleeding in sequence. nasal obstruction take the portion of 95%, postnasal dripping 65%, night time or early morning cough 60%. 5. The suffering period of sinusitis is 6 month minimum, 4 years maximum, most cases are included in a year. The suffering period of children was shorter than adult. 6. Diagnosis depend on inspection of nasal cavity, postnasal dripping, X-ray finding. 75% of patient(15case) showed both maxillary sinusitis, 25%(5cases) showed left or right maxillary sinusitis. 7. Treatment of oriental medicine, consist of Herb-medicine, acupuncture and exposing of Lazer beam. Kamihyunggyeyungyotang(加味荊芥蓮翹湯) is administered mainly as the medical therapy, Kamigwaghyangjeungkisan(加味藿香正氣散) Kimizwakwieum(加味左歸飮), Kamihyangsosan(加味香蘇散) is administered for a additional symptoms which occurred by influenza recurrence. Kamijeonxibackchulsan(加味錢氏白朮散) is administered to treat gastro-intestine trouble patients who have sinusitis. 8. The period of treatment is varied with patient conditions and X-ray finding. The minimal period is 35days, maximal period is 202days. So it took about 86days in average and about 50% of patient(10cases) is recovered in one or two month.