• 제목/요약/키워드: Lateral lines

검색결과 187건 처리시간 0.023초

Static and seismic active lateral earth pressure coefficients for c-ϕ soils

  • Keshavarz, Amin;Pooresmaeil, Zahra
    • Geomechanics and Engineering
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    • 제10권5호
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    • pp.657-676
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    • 2016
  • In this paper, the active lateral earth pressure is evaluated using the stress characteristics or slip line method. The lateral earth pressure is expressed as the lateral earth pressure coefficients due to the surcharge, the unit weight and cohesion of the backfill soil. Seismic horizontal and vertical pseudo-static coefficients are used to consider the seismic effects. The equilibrium equations along the characteristics lines are solved by the finite difference method. The slope of the ground surface, the wall angle and the adhesion and friction angle of the soil-wall interface are also considered in the analysis. A computer code is provided for the analysis. The code is capable of solving the characteristics network, determining active lateral earth pressure distribution and calculating active lateral earth pressure coefficients. Closed-form solutions are provided for the lateral earth pressure coefficients due to the surcharge and cohesion. The results of this study have a good agreement with other reported results. The effects of the geometry of the retaining wall, the soil and soil-wall interface parameters are evaluated. Non-dimensional graphs are presented for the active lateral earth pressure coefficients.

인공잡음 발생장치를 이용한 초고압 시험선로의 잡음 방사특성 연구 (A Study on the Radiation Characteristics of Noise from HV AC Transmission Lines Using a Gap Noise Generator)

  • 신구용;이동일;김상범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2041-2043
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    • 1999
  • In order to investigate the radiation characteristics of unmixed line noise from overhead high voltage AC transmission lines, a gap noise generator was manufactured. Disk size which decides capacitance between the noise generator and earth was selected through preliminary indoor experiments and analysis by charge simulation method. The capacitance is one of principal parameters related to inject a proper noise current into lines. The field experiments were performed with the noise generator installed in Kochang 765 kV full scale test line. As the results, the useful data which can be used to analysis the radiation characteristics of noise from transmission lines was obtained. Those are lateral profiles the directivity of antenna toward lines, frequency spectra and so on.

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Quantitative cone-beam computed tomography evaluation of hard and soft tissue thicknesses in the midpalatal suture region to facilitate orthodontic mini-implant placement

  • Oh, Song-Hee;Lee, Sae Rom;Choi, Jin-Young;Kim, Seong-Hun;Hwang, Eui-Hwan;Nelson, Gerald
    • 대한치과교정학회지
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    • 제51권4호
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    • pp.260-269
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    • 2021
  • Objective: To identify the most favorable sites that optimize the initial stability and survival rate of orthodontic mini-implants, this study measured hard and soft tissue thicknesses in the median and paramedian regions of the palate using cone-beam computed tomography (CBCT) and determined possible sex- and age-related differences in these thicknesses. Methods: The study sample comprised CBCT images of 189 healthy subjects. The sample was divided into four groups according to age. A grid area was set for the measurement of hard and soft tissue thicknesses in the palate. Vertical lines were marked at intervals of 0, 1.5, and 3.0 mm lateral to the midpalatal suture, while horizontal lines were marked at 2-mm intervals up to 24 mm from the posterior margin of the incisive foramen. Measurements were made at 65 points of intersection between the horizontal and vertical lines. Results: The palatal hard tissue thickness decreased from the anterior to the posterior region, with a decrease in the medial-to-lateral direction in the middle and posterior regions. While the soft tissue was rather thick around the lateral aspects of the palatal arch, it formed a constant layer that was only 1-2-mm thick throughout the palate. Statistically significant differences were observed according to sex and age. Conclusions: The anterolateral palate as well as the midpalatal suture seem to be the most favorable sites for insertion of orthodontic mini-implants. The thickness of the palate differed by age and sex; these differences should be considered while planning the placement of orthodontic mini-implants.

POSSIBLE PRESENCE OF LATERAL INFLUX OF THE PHOTOSPHERIC RADIATION WITHIN SUNSPOTS

  • Yun, Hong-Sik;Kim, Hyun-Goo
    • 천문학회지
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    • 제16권1호
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    • pp.19-22
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    • 1983
  • The reduced profiles of $C_2$ 5150.56, CN 3864.32, MgH 5150.20 and FeI 5150.84 lines, representing the penumbra, the penumbra-umbra boundary and the umbra of spa 6403 have been analyzed by comparing them with the synthetic profiles computed from a set of umbral and penumbral models. The results are presented and discussed. It is suggested that there may be a significant lateral flow of pbotospheric radiation into the umbral and penumbral regions of the sunspots.

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초음파 영상장치에서 측방향 해상도 향상에 관한 연구 (A Study on the Improvement a Lateral Resolution of the Ultrasound Imaging System)

  • 이후정;이행세
    • 대한의용생체공학회:의공학회지
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    • 제9권1호
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    • pp.87-92
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    • 1988
  • In this paper, a new focusing method, to be called the pipelined sampled delay focusing (PSDF), is implemented. This method improves the lateral resolution in ultrasound imaging system. In PSDF, the analog belay lines are no longer necessary because sampling sum process can replace the conventional delay sum process. Also, the method offers continuous dynamic focusing on the resolution pixel basis, and eliminates the constraint that the maximum delay time is less than the sampling interval. Second order sampling is adopted in order to extend the sampling interval.

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Experimental Investigations on the Plastic Damage of Plates due to Lateral Collisions

  • Cho, Sang-Rai;Kim, Il-Woong;Lee, Sang-Bock
    • Journal of Ship and Ocean Technology
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    • 제6권3호
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    • pp.1-12
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    • 2002
  • In this paper the results are reported of sixty-nine lateral collision tests, which were performed to investigate the collision resistance of plates. For the tests a collision testing machine of spring-roller conveyer type was designed and fabricated. Using this machine, various plates were tested with different masses and velocities and various headers of the striker. A simple analytical method has also been developed to predict the extent of damage of struck plates due to lateral collision. In the method, it is assumed that the kinetic energy of the striker can be dissipated by the formation of yield lines and membrane tensions in the impacted plate. The calculated predictions of extent of damage using the developed method have been substantiated with the test results, which shows reasonably acceptable correlations.

구외 방사선사진 촬영에 사용되는 기준선의 상호 관계 (The relationship among reference lines used for taking the extraoral radiography)

  • 이설미;최항문
    • Imaging Science in Dentistry
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    • 제31권4호
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    • pp.205-207
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    • 2001
  • Purpose : The aim of present study is to estimate the relationship among reference lines used for taking the extraoral radiography and panoramic radiography. Materials and Methods: Lateral cephalographs of 40 adults, aged 22 to 30 years were taken. Angles between reference lines (Frankfort line, canthomeatal line, infraorbitomeatal line, and occlusal plane) were measured. Results: Angles between Frankfort line and canthomeatal line, Frankfort line and infraorbitomeatal line, Frankfort line and occlusal plane, canthomeatal line and infraorbitomeatal line, canthomeatal line and occlusal plane, and infraorbitomeatal line and occlusal plane were 16.1° (±2.2), 5.8° (±2.4), 8.7° (±3.5), 10.3° (±1.3), 24.8° (±4.0), and 14.5° (±4.4),respectively. Conclusion: Angle between frankfort and canthomeatal line is very different with commonly known angle. Frankfort horizontal reference lines used for panoramic radiography need an exact definition and more accurate standard is needed for the taking of panoramic radiograph.

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Diagnostic analysis of vertical orbital dystopia and canthal tilt for surgical correction

  • Lee, Ju-Young;Choung, Han-Wool;Choung, Pill-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제46권6호
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    • pp.379-384
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    • 2020
  • Objectives: We sought to identify a clinically useful method of analyzing orbital dystopia to aid in diagnosis and treatment planning and to quantify vertical discrepancies in eye level and variations in canthal tilt in Koreans. Patients and Methods: In 76 Korean patients with a mean age of 23.12 years, mean differences in the level of the pupils, lateral canthi, medial canthi, and canthal tilt were measured. The difference in pupil level was calculated from the perpendicular lines drawn from the midpupil area of each eye to the midline of the face to determine the amount of skeletal discrepancy of the eye. Soft tissue discrepancies were determined according to the vertical difference between the lines drawn from the lateral or medial canthus of each eye perpendicular to the midline of the face. The canthal tilt was determined from the inclination of a line connecting the lateral and medial canthi, then classified as class I, II, or III. Results: Mean differences in pupil level, medial canthi, and lateral canthi were 1.57±1.10 mm, 1.14±1.07 mm, and 2.03±1.64 mm, respectively. The mean degree of canthal tilt were 8.45°±3.53° for the right side and 8.42°±3.81° for the left side. No study participants presented with class III canthal tilt. The mean canthal tilt values for those with class I tilt were 3.21°±1.68° for the right side and 3.18°±1.63° for the left side, while, for those who had class II tilt, the values were 9.60°±3.66° for the right side and 9.54°±2.99° for the left side. Conclusion: The presented diagnostic method of orbital dystopia can be used to effectively establish a treatment plan that takes into consideration the patient's skeletal and soft-tissue discrepancies.

Power Frequency Magnetic Field Reduction Method for Residents in the Vicinity of Overhead Transmission Lines Using Passive Loop

  • Lee, Byeong-Yoon;Myung, Sung-Ho;Cho, Yeun-Gyu;Lee, Dong-Il;Lim, Yun-Seog;Lee, Sang-Yun
    • Journal of Electrical Engineering and Technology
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    • 제6권6호
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    • pp.829-835
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    • 2011
  • A power frequency magnetic field reduction method using passive loop is presented. This method can be used to reduce magnetic fields generated within the restricted area near transmission lines by alternating current overhead transmission lines. A reduction algorithm is described and related equations for magnetic field reduction are explained. The proposed power frequency magnetic field reduction method is applied to a scaled-down transmission line model. The lateral distribution of reduction ratio between magnetic fields before and after passive loop installation is calculated to evaluate magnetic field reduction effects. Calculated results show that the passive loop can be used to cost-effectively reduce power frequency magnetic fields in the vicinity of transmission lines generated by overhead transmission lines, compared with other reduction methods, such as active loop, increase in transmission line height, and power transmission using underground cables.

20대 남성의 상반신 측면형태에 따른 치수변화에 관한 연구 (A Study on the Size Changes of Men in the 20′s - Focusing on the Lateral View of their Upper Bodies -)

  • 곽연신;김애린
    • 복식
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    • 제54권2호
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    • pp.149-165
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    • 2004
  • In this study, the photographic and anthropometric measurements of men in the 20's were made. and pattern making professionals visually evaluated their side photos to classify lateral views. These data were analyzed by being compared with existing research results to select objective standards, and body types were classified according to the selected standard. In addition, body features were defined according to lateral views based on measurement items and indices, and standard lines and determining factors for visual evaluation which determines lateral views were revealed. Back length - front length size smaller than 1.5cm was named as the lean-back type, 1.5∼3.9cm was named as the straight type. and that larger than 3.9cm was named as the bend-forward type. In the straight type, the bisection point of waist depth was located at a similar place to tragion level vertical line. In the lean-back type, the point was at the front of tragion level vertical line. In the bend-forward type, the point was at the back of tragion level vertical line.