• Title/Summary/Keyword: transverse measurements

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Evaluation of the maxillary intermolar width (U6-U6) on frontal cephalogram (정모두부방사선선사진을 이용한 상악 제 1대구치간 폭경의 평가)

  • Park, Young Guk;Chung, Kyu Rhim;Lee, Young-Jun;Lee, Soung Hee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.16 no.1
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    • pp.61-67
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    • 2000
  • It was the aim of present study to grope the relationship of the maxillary first molar width to the various transverse skeletal measurements in frontal headfilm, and to formulate the predictive equations of the maxillary intermolar width (U6-U6) from each of the variables. Frontal cephalograms of 17 males from 18 to 26 YO and 13 females from 17 to 25 YO who manifested balanced skeletal profiles, normal occlusion, and no history of orthodontic and prosthodontic treatment were employed as subjects. Nine transverse measurements were scrutinized with Pearson's correlation analysis, simple and stepwise multiple regression analysis in specific regards to the intermolar width of maxillary first molar. Statistical output demonstrated that there were intimate relationships within the various transverse skeletal measurements each other, and among the others, high correlation was found between facial width and maxillary first intermolar width. Regression analyses provided the reliable and clinically applicable predictive equations to set the ideal maxillary first intermolar width(U6-U6) from the given skeletal framework.

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Cone-beam computed tomography analysis of transverse dental compensation in patients with skeletal Class III malocclusion and facial asymmetry

  • Lee, Ji-Yea;Han, Sung-Hoon;Ryu, Hyeong-Seok;Lee, Hee-Min;Kim, Sang-Cheol
    • The korean journal of orthodontics
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    • v.48 no.6
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    • pp.357-366
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    • 2018
  • Objective: The purpose of this study was to analyze the transverse dental compensation in reference to the maxillary and mandibular basal bones using cone-beam computed tomography (CBCT) and evaluate the correlations between transverse dental compensation and skeletal asymmetry variables in patients with skeletal Class III malocclusion and facial asymmetry. Methods: Thirty patients with skeletal Class I (control group; 15 men, 15 women) and 30 patients with skeletal Class III with menton deviation (asymmetry group; 16 men, 14 women) were included. Skeletal and dental measurements were acquired from reconstructed CBCT images using OnDemand3D 1.0 software. All measurements were compared between groups and between the deviated and nondeviated sides of the asymmetry group. Correlation coefficients for the association between skeletal and dental measurements were calculated. Results: Differences in the ramus inclination (p < 0.001), maxillary canine and first molar inclinations (p < 0.001), and distances from the canine and first molar cusp tips to the midmaxillary or midmandibular planes (p < 0.01) between the right and left sides were significantly greater in the asymmetry group than in the control group. In the asymmetry group, the ramus inclination difference (p < 0.05) and mandibular canting (p < 0.05) were correlated with the amount of menton deviation. In addition, dental measurements were positively correlated with the amount of menton deviation (p < 0.05). Conclusions: Transverse dental compensation was correlated with the maxillary and mandibular asymmetry patterns. These results would be helpful in understanding the pattern of transverse dental compensation and planning surgical procedure for patients with skeletal Class III malocclusion and facial asymmetry.

Measurement of Transverse Strain Using PMBG Sensor (PMFBG 센서를 이용한 횡방향 변형률 측정)

  • 윤혁진;김대현;홍창선;김천곤
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2002.05a
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    • pp.27-30
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    • 2002
  • PMFBG sensor was fabricated using phase mask and Excimer laser. The reflected wavelength of PMFBG sensor had dual peaks due to intrinsic birefringence. To discover the polarization axes, peak sensitivity was measured under compression test. The signal characteristics of PMFBG sensor were also examined in embedding condition. The embedded PMFBG sensor in epoxy block was loaded for the transverse strain measurements. Experiments showed that the PMFBG sensor could successfully measure the transverse strain. This PMFBG sensor is useful for the structures that require measuring transverse stram.

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EFFECT OF SURFACE CONTAMINATION ON THE TRANSVERSE STRENGTH OF THE RELINED DENTURE (첨상면 오염이 레진 의치상의 파절강도에 미치는 영향)

  • Kim, Jeong-Hyun;Bae, Jung-Soo;Han, Dong-Hoo
    • The Journal of Korean Academy of Prosthodontics
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    • v.31 no.1
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    • pp.11-18
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    • 1993
  • Autopolymerising and visible light cured resin are used to reline dentures. But relined surface are easily contaminated by water or saliva in the mouth during clinical procedure. This study was to find out the effect of surface contamination on the transverse strength of the relined denture base. To accomplish this, the specimens of $65\times10\times3mm$ were made with heat-cured(Lucitone 199), visible light-cured(Triad), and autopolymerizing resin(Kooliner). Measurements of transverse strength were taken for each specimen. Specimens made of heat-cured resins, sizing $65\times10\times1.5mm$, were relined with heat-cured, light-cured, and autopolymerizing resin, respectively. Specimens relined with autopolymerizing and light-cured resins were further classified into not-contaminated, water-contaminated and saliva-contaminated groups. Again, measurements of the transverse strength were taken for each group. The results were as follows 1. The transverse strength of heat-cured resin was superior to all the other resins. 2. The transverse strength of each specimen decreased after relining in the following order, heat-cured, visible light-cured, and autopolymerizing resin. 3. Surface contamination produced an decrease in transverse strength, especially in the saliva contaminated group. According to these results, water or saliva contamination should be avoided during intraoral relining procedures.

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Maxillomandibular arch width differences at estimated centers of resistance: Comparison between normal occlusion and skeletal Class III malocclusion

  • Koo, Yun-Jin;Choi, Sung-Hwan;Keum, Byeong-Tak;Yu, Hyung-Seog;Hwang, Chung-Ju;Melsen, Birte;Lee, Kee-Joon
    • The korean journal of orthodontics
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    • v.47 no.3
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    • pp.167-175
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    • 2017
  • Objective: To evaluate the differences in maxillomandibular transverse measurements at either the crown or the estimated center of resistance (CR), and to compare values between normal occlusion and Class III malocclusion groups. Methods: Dental casts and computed tomography (CT) data from 30 individuals with normal occlusion and 30 with skeletal Class III malocclusions were evaluated. Using the casts, dental arch widths (DAWs) were measured from the cusp tips, and basal arch widths (BAWs-cast) were measured as the distance between the points at the mucogingival junction adjacent to the respective cusp tips. The BAWs determined from CT (BAWs-CT) images were measured from the estimated CRs of the teeth. Results: None of the DAW measurements or maxillomandibular DAW differences showed statistically significant intergroup differences. In contrast, the maxillary BAWs-CT and BAWs-cast were lesser in the Class III malocclusion group than in the normal occlusion group. The mandibular BAWs-CT were significantly greater in the Class III malocclusion group than in the normal occlusion group. Moreover, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. Conclusions: The maxillomandibular DAW differences showed no significant intergroup differences. In contrast, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. The maxillomandibular BAW differences at the estimated CRs, measured using CT or casts, can reveal underlying transverse maxillary basal arch deficiencies in patients with skeletal Class III malocclusions.

Calculation of the coupled free, transverse vibrations of the multi-supported shaft system by transfer matrix method (전달매트릭스법에 의한 다점지지축계의 연성자유횡진동계산에 관한 연구)

  • 안시영;전효중
    • Journal of Advanced Marine Engineering and Technology
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    • v.7 no.1
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    • pp.49-63
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    • 1983
  • Coupled transverse shaft vibrations have become the target of great concern in high powered ships such as container ships. Due to increasing ship's dimensions and high propulsive power, resonance frequencies of the propeller shaft system tend to decrease and can appear in some cases within the operating speed range of engine. In this connection, the coupled free transverse vibrations of shaft system in two planes are theoretically investigated. This shaft system carries a number of discs and is flexibly supported by a number of bearing stiffness are considered for the calculation. Transfer matrix method is applied to calculate the shaft responses in both planes. A digital computer program is developed to calculate the shaft responses of the coupled transverse vibrations in two planes. An experimental model shaft system is made. It is composed of a disc, shafts, ball bearings thrust bearings and flexible bearing supports. The shaft system is excited by an electrical magnet, and shaft vibration responses in two planes are measured with the strain gage system. From these measurements, the natural frequencies of the shaft system in both planes are found out. The developed program is also used to calculate the shaft vibration responses of experimental model shaft system. From the results of these calculations, the natural frequencies of shaft system in two planes are derived. Theoretical predictions of model shaft natural frequencies show good agreements with its esperimental measurements.

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Morphological types and morphometrical measurements of the suprascapular notch in both dry bones and human cadavers: anatomical study to improve the outcomes of the diagnostic and interventional procedures in the shoulder region

  • Ashraf Youssef Nasr
    • Anatomy and Cell Biology
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    • v.56 no.4
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    • pp.482-493
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    • 2023
  • Understanding the anatomy of suprascapular area helps the clinicians and surgeons in management of any disability at the shoulder region. This work aimed to clear the different morphological and morphometrical types of suprascapular notch (SSN). Unknown 120 dry human scapulae of both sides and 60 formalin-embalmed cadaveric upper limbs (40 males and 20 females) were used in the present study. Three main morphological forms of SSN were reported: J, U, and V-shaped. J-shaped notch showed the highest incidence followed by U-shaped then V-shaped one. Morphometrically, type (III) notch was the most prevalent in both dry bones and cadavers, while the incidence of type (II) was the lowest form. Also, the measurements of superior transverse diameter, middle transverse diameter and vertical dimension of the different types of the notch showed no side or sex significant difference. The suprascapular foramen with ossified superior transverse scapular ligament (STSL) was seen in 5.8% of dry bones and 10% of cadaveric specimens. Fan and band-shaped ossified transverse scapular ligaments were reported. Absence of SSN was seen in 10.8% of dry bones, 7.5% of male and 10% of female specimens with left side predominance. V-shaped, absence, and ossified STSL were considered as predisposing factors of suprascapular nerve entrapment syndrome. Knowledge of the morphology and morphometric parameters of SSN is of great clinical significance for anatomists, radiologists, physiotherapists, orthopedics and neurosurgeons to perform good diagnosis and best planning for surgical or arthroscopic interventions within the shoulder region.

Prediction of a transverse shrinkage of butt welded joints in shipyard conditions using the design of experimental approach

  • Urbanski, Tomasz;Taczala, Maciej
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.784-798
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    • 2020
  • This paper presents the results of research on transverse shrinkage of welded butt joints conducted according to the principles of experimental design and under production conditions for two main welding techniques used in shipbuilding (FCAW and SAW). Analysis took into account the technological and structural parameters influencing the assembly suitability of a large steel structure. The presented method of evaluation makes it possible to apply approximation formulae to predict transverse shrinkage in real sections of a ship hull. The determined predictive formulae were verified to actual transverse shrinkage measurements during prefabrication of hull sections at a shipyard as well as the equations referring to the analyzed form of deformation available in the literature.

A Study on Transverse Edge Effect in Linear Induction Motor With Sheet Rotor (Sheet Rotor를 가진 직선형 유도전동기의 Transverse Edge Effect에 관한 연구)

  • Yun Jong Lee;Dal Ho Im;Soo Hyun Baek
    • 전기의세계
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    • v.23 no.4
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    • pp.39-45
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    • 1974
  • In most previous research work, the transverse edge effect has been allowed for only by use of a relativity-increase factor. This paper gives a more exact treatment. A two-dimensional-field analysis is presented for the problem of sheet rotor linear induction motor with finite width the method used takes account of flux leakage in the space between the stator and secondary sheet rotor as well as in the secondary itself. Equations are derived for the flux density distribution in the air gap and for the starting face, in each case as a function of stator current. The cross gap flux density peaks towards athe edge of the stator. This phenomena is known as the transverse edge effect. Measurements of the flux density in the air gap and starting force on a linear induction motor with sheet rotor of different width showed a reasonable agreement,suggest that it would be desirable to take into account also, at least for this motor in which severe redistribution occurs.

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Flow Characteristics and Transverse Bed Slope in Curved Alluvial Channels (만곡 수로의 횡방향 하상경사와 흐름특성)

  • 차영기;이대철
    • Water for future
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    • v.24 no.1
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    • pp.99-107
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    • 1991
  • This study is for simulating to the model which analyzes flow characteristics and transverse bed slopes in a coarse-streambed of the meandering alluvial channels. Using the equations for conservation of mass, momentum, and for lateral stability of the streambed, a linear differential equation of transverse bed slope is derived from the flow characteristics in curved channels. Its solutions are solved by the Sine-generated curve method(SCM) and compared with results of field measurements. Lag distances by the maximum transverse bed slope and velocity profiles will predict risk sections of concave bank under floods.

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