• 제목/요약/키워드: maximum protrusion

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주름진 덕트에서 딤플/돌출 형상이 열전달계수에 미치는 영향 (Effects of dimple/protrusion array on heat transfer coefficients in rectangular wavy duct)

  • 권현구;황상동;조형희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2352-2356
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    • 2008
  • Heat transfer and performance characteristics have been investigated for a rectangular wavy duct with dimple or protrusion arrays. The test duct was 15mm in height and 105mm wide. The print diameter of the dimple/protrusion wall was 12.99mm and the depth/height of the dimple/protrusion was 3.75mm. Local heat transfer coefficients on the dimple/protrusion wall were measured using a transient TLC technique. The Reynolds number was varied from 3,000 to 10,000. For the wavy duct tested in this study, adverse static pressure characteristics occurred at turning region of the wavy duct due to secondary flows. For the wavy duct with protrusion array, higher heat transfer enhancement level of 7.4 times than smooth straight case in maximum was obtained at low Reynolds number due to the high heat transfer enhancement by vortex flows. Also, the protrusion array increased the performance level of 3.0 at low Reynolds number of 3,000.

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전치부 개교환자의 하악 운동에 관한 연구 (A STUDY ON THE MANDIBULAR MOVEMENT OF ANTERIOR OPENBITE PATIENTS)

  • 곽재영;김광남;장익태
    • 대한치과보철학회지
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    • 제32권2호
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    • pp.281-295
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    • 1994
  • It is very important for the ideal restorations of anterior openbite patients to record the mandibular movement and to harmonize mandibular movement with other organs in stomatognathic systems. This study was designed to compare the mandibular movement of anterior openbite patients with that of normal bite(Angle Class I) patients, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Saphon Visi-trainer Model 3(Tokyo Shizaisha Co. Japan) and Denar Pantronic(Denar Corp.,U.S.A.) were used to record mandibular movement. Pantronic survey was peformed by using an arbitrary hinge axis according to manufacturer's direction. Twenty-eight adult who have physiologically normal occlusion(Angle Class I) and are free of TM dysfunction were selected as a control group(Group 1). Fifteen adult who are anterior openbite patient and have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). The results are as follows : 1. There was no statistically significant difference between the average immediate and progressive side shift of anterior openbite patients(0.54mm, $7.57^{\circ}$) and those of normal group(0.49mm, $5.96^{\circ}$). 2. The average protrusive and orbiting condylar inclination of anterior openbite patient$(30.87^{\circ},\;32.27^{\circ})$ were significantly lower than those of normal group$(36.11^{\circ},\;39.04^{\circ})$ (P<0.05). 3. In the results of Visi-trainer recordings, the mean for the maximum protrusion, the maximum laterotrusion, the angle of laterotrusion and the angle of protrusion in the horizontal trajectory between group 1 and 2 did not differ significantly. 4. The mean for the angle of protrusion, the maximum opening in the frontal trajectory, the ICP-RCP(A-P) distance and the angle of protrusion in the sagittal trajectory differ significantly(P<0.05). 5. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.

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설소대 절단술의 결정 요인에 관한 기초 연구: Boley gauge를 이용한 3$\sim$6세 정상 아동의 혀의 최대 신장 길이 계측 (A Preliminary Study on the Determining Indicatory Factors for Frenulotomy: Maximum Lingual Length-Protrusion of 3-6 Year Old Normal Children with Boley Gauge (Digimatic Caliper$Caliper^{(R)}$))

  • 최재남;표화영;심현섭;최흥식
    • 음성과학
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    • 제8권3호
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    • pp.161-172
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    • 2001
  • Ankyloglossia (tongue-tie) limits movement of the tongue connected with feeding and has adverse impacts on both dental health and speech. For the patients with ankyloglossia, surgical intervention is recommended as primary treatment. This study suggests the efficient tool in determining indicatory factors for frenulotomy by quantifying Maximum Lingual Length-Protrusion (MLL-P) with boley gauge, and as a preliminary study, to show the measurement results with normal children using the tool. The subjects were 61 normal children, and the distance (MLL-P) between mandibular central incisor and tongue tip during tongue protrusion was measured with a boley gauge (Digimatic $Caliper^{(R)}$). The results of this study can be summarized as follows: (1) The mean value of MLL-P (N=61 normal children) was 21.44 mm, (2) The mean value of MLL-P was 20.69 mm in males (N=33) and 21.91 mm in females (N=28). There was no statistically significant difference between males and females, (3) The mean value of MLL-P was 19.34 mm, 21.19 mm, 22.33 mm, 22.61 mm for measurement of 3-, 4-, 5- and 6-year-old children, respectively, and (4) The mean value of MLL-P showed statistically significant difference between 3- and 5-year-old children, between 3- and 6-year old children.

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정상교합과 III급 부정교합아동의 하악운동 범위에 대한 연구 (A STUDY ON THE RANGE OF MANDIBULAR MOVEMENT OF NORMAL AND CLASS III MALOCCLUSION CHILDREN)

  • 지인애
    • 대한소아치과학회지
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    • 제11권1호
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    • pp.41-56
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    • 1984
  • The purpose of this study is to obtain the normal range of mandibular movement for 13 year old boys and girls, and to compare it to the range of mandibular movement of class III patient and normal adult for diagnosis and prognosis of class III malocclusion and TMJ dysfunction. The subjects were 20 normal boys 20 normal girls 22 class III boys and 18 class III girls. The author measured the ranges and shapes of movement of the mandible in the frontal, sagittal and horizontal trajectories using Saphon visitrainer C II (Tokyo Shizaisha Inc.) for the subjects. The results obtained are as follows: 1) The mean for maximum right laterotrusion in the frontal trajectory were 11.96mm in N.B., 11.10mm in N.G., 11.32mm in III. B., 11.24mm in III G. The mean for maximum left laterotrusion were 11.48mm, 11.0mm, 10.91mm, 10.44mm respectively, Area of border movement were 7.16cm in N.B., 6.59cm in N.G., 7.29cm in III. B., 7.50cm in III. G. 2) The mean for maximum protrusion in the sagittal trajectory were 11.7mm in N.B., 11.4mm in N.G.,11.87mm in III B., and 11.02mm in III. G. 3) The mean for maximum protrusion in the horizontal trajectory were 10.20mm in N.B.,10.00 mm in N.G., 9.12mm for III. B. and 9.36mm in III. G. 4) The mean for maximum protrusion of Class III subjects were shorter than those of normal subjects. 5) There was no sexual difference in the range of mandibular movement for 13 year old subjects. N.B; Normal boys N.G.; Normal girls III.B.; Class III boys III. G.; Class III girls.

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돛새치 피부는 상어 피부처럼 마찰저항을 줄일 수 있을까? (Does the Sailfish Skin Reduce the Skin Friction Like the Shark Skin?)

  • 사공웅;김철규;최상호;전우평;최해천
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.101-104
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    • 2008
  • The sailfish is the fastest sea animal, reaching its maximum speed of 110km/h. On its skin, a number of V-shaped protrusions pointing downstream exist. Thus, in the present study, the possibility of reducing the skin friction using its shape is investigated in a turbulent boundary layer. We perform a parametric study by varying the height and width of the protrusion, the spanwise and streamwise spacings between adjacent ones, and their overall distribution pattern, respectively. Each protrusion induces a pair of streamwsie vortices, producing low and high shear stresses at its center and side locations, respectively. These vortices also interact with those induced from adjacent protrusions. As a result, the drag is either increased or unchanged for all the cases considered. In some cases, the skin friction itself is reduced but total drag including the form drag on the protrusions is larger than that of a smooth surface. Since the shape of present protrusions is similar to that used by Sirovich and Karlsson [Nature 388, 753 (1997)] where V-shaped protrusions pointing upstream were considered, we perform another set of experiments following their study. However, we do not obtain any drag reduction even with random distribution of those V-shaped protrusion.

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악관절 폐구성 과두걸림 환자의 하악운동에 관한 연구 (A Study on the Mandibular Movements in the Patients with TMJ Lock Closed)

  • Ji-Won Lee;Sung-Chang Chung
    • Journal of Oral Medicine and Pain
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    • 제15권1호
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    • pp.79-89
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    • 1991
  • The author examined the patterns and various ranges of mandibular movements in TMJ lock closed patients in the frontal, sagittal and horizontal plane and obtained the following results. 1. In the frontal trajectory, the mean amount of maximum mouth opening was 24.4mm and the opening paths were deviated to the affected side in 87.1% of the patients. The mean amount of maximum laterotrusion to the affected side was 10.4mm and that of non-affected side was 7.5mm. There was a significant difference between them(p<0.001). 2. In the sagittal trajectory, the mean amount of the maximum protrusion was 7.0mm, the mean amount of the maximal retrusion was 1.0mm 3. In the horizontal trajectory, the pattern of laterotrusion showed asymmetry: the mean length of non-affected side was smaller than that of the affected side. Protrusive path were deviated to the affected side in 64.5% of the patients, the mean degree of deviation was 16.4$^{\circ}$. The mandibular movements of TMJ lock-closed patients can be characterized by decreased range of mouth opening, protrusive movement, and laterotrusive movement to the non-affected side and also characterized by deviated opening and protrusive path to the affected side.

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양측성 하악지 시상분할술을 이용한 악교정 수술시술 후 교합력과 근전도 변화 (THE OCCLUSAL FORCE AND EMG CHANGE AFTER BSSRO)

  • 이성규;최용관;황대용;김경욱
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제34권5호
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    • pp.537-542
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    • 2008
  • BSSRO is most frequently operated among orthognathic surgery techniques for repairment of maxillofacial deformities. In case of patients with maxillofacial asymmetry accompanying mandibular protrusion who are operated by BSSRO, this study considers the recovering time for masticatory force of each tooth and Masseteric EMG and the adequate time enabling normal occlusion. The patients who are operated with BSSRO under general anesthesia in Dankook Dental Hospital, Department of OMS are selected for this study. The control group is devided into 2. 26 patients with facial asymmetry accompanying mandibular protrusion are selected for group 1 and their maximum voluntary bite force and masseteric EMG are measured. Group 2 is formed by volunteers with healthy dentition who are measured maximum bite force and masseteric EMG on both sides of the mouth. At the week of 3rd, 5th, 7th, 9th and 11th, Mann-Whitney U test is carried on for statistical analysis and the result is as follows. 1. Patients with mandibular protrusion showed apparently low maximum bite force and masseteric EMG than patients with normal occlusion. 2. In comparison with control group 1, Occlusal force is regained in incisors and canines at the 9th week and in premolars and molars, 11th week and masseteric EMG is regained at 11th week. 3. Comparing to normal occlusal patients, no recovery could be found in experimental group in every parts of the mouth.

악관절음 환자의 하악 비틀림회전운동에 관한 연구 (A Study on Mandibular Rotational Torque Movement in Subjects with Temporomandibular Joint Sounds)

  • 소종섭;이경호;정성창
    • Journal of Oral Medicine and Pain
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    • 제24권4호
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    • pp.455-466
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    • 1999
  • The purpose of this study was to investigate the magnitude of mandibular rotational torque movements in subjects with TMJ sounds, and to analyse correlation between quantitative characteristics of TMJ sounds and mandibular rotational torque movement. Twenty dental college students with TMJ clicking and twenty students without any TMD signs and symptoms were examined by mean of SonoPak and Rotate program of BioPAK system(Bioresearch Inc. MilWaukee, wisconsin, USA) in this study. Mandibular rotational torque movements were recorded and analysed during maximum mouth opening, protrusion, and lateral excursion in frontal and horizontal planes. The obtained results were as follows: 1. On maximum mouth opening, mandibular rotational angle and distance of clicking group were significantly greater than those of control group in frontal plane. (P<0.05). 2. During maximum mouth opening closing, maximum mandibular rotational angle and distance of clicking group were significantly greater than those of control group in frontal plane. (P<0.01). 3. On protrusion, mandibular rotational angle and distance of clickin group were significantly greater than those of control group in horizontal plane. (P<0.05). 4. On lateral excursion, there was no significant difference in mandibular rotational angle and distance between clicking group and control group in frontal and horizontal planes. 5. There were significant correlations between peak amplitude of TMJ sounds and maximum mandibular rotational distance during maximum mouth opening (r=-.481) and mandibular rotational distance on maximum mouth opening (r=-.455) in horizontal plane. 6. There were significant correlations between Above 300/(0-300)Hz ratio of TMJ sounds and mandibular rotational angle (r=-.499) and distance (r=-.457) on maximum mouth opening in frontal plane.

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악관절 폐구성 과두걸림 환자의 하악운동에 관한 연구 -치료전후의 하악운동 범위 및 양상 - (A Study on the Mandibular Movements in the Patients with TMJ Lock Closed -Range and pattern of mandibulr movement-)

  • Sung-Chang Chung;Hyung-Suk Kim
    • Journal of Oral Medicine and Pain
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    • 제16권1호
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    • pp.113-120
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    • 1991
  • The authors examined the patterns and various ranges of mandibular movements in TMJ lock closed patients in the frontal, sagittal and horizontal plane pre-end post-treatment. And the author obtained the following results. 1. In the frontal plane, the patterns and ranges of mandibular movement of the patients were very irregular and small before treatment. But after the treatment, the patterns were similar to the typical shield shape of the normal subjects. And the velocity of opening and closing was improved after the treatment. 2. In the sagittal plane, the mean amount of maximum mouth opening was 27.0±4.0mm before treatment and 44.0±5.4mm after treatment. And there was statistically significant improvement(p<0.005). The patterns of the movement were very irregular and small before treatment, but were similar to the shape of "Posselt's envelope of motion" after the treatment. The velocity of opening and closing was improved after the treatment 3. In the horizontal plane, the mean amount of maximum laterotrusion was 8l2±2.5mm in the affected side and 6.7±2.2mm in the non-affected side before treatment. There was a significant difference between the sides(p<0.05). After the treatment, the mean was 10.4±2.6mm in the affected side and 8.9±2.3mm in the non-affected side and there was no significant difference between the sides(p>0.05). There was no significant difference in the mean amount of maximum protrusion between the before and aftertreatment(p>0.05), but the patterns of the movements were improved.

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국부지역 이진 패턴 분석법에 기초한 단락 및 돌기형 FAB불량 검출기법 (A Method of Detecting Short and Protrusion-type FAB Defects Based on Local Binary Pattern Analysis)

  • 김진수
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2013년도 추계학술대회
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    • pp.1018-1020
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    • 2013
  • PCB 제작 분야에서 TCP와 COF에서는 전기적인 특성검사만으로 자동화를 이루어지고 있으며, 실제 단락 및 돌기(근사단락) 형태의 데이터 불량 등에 대해서는 노동력을 동원해 불량을 검출하고 있는 실정이다. 본 논문에서는 영상처리에 의해 국부지역패턴 분석법에 기초한 검출기법을 제안한다. 제안한 방법은 히스토그램보정, 공간위치보정 및 최대왜곡좌표를 구하는 전처리 과정을 포함하여, 지역기반의 패턴분석법이 적용된다. 모의실험을 통하여 제안한 방식은 기존의 영역기반의 검출기법에 비해 성능이 개방 및 근사개방 결함 검출에서 크게 성능을 개선할 수 있음을 보인다.

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