• Title/Summary/Keyword: horizontal growth

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A STUDY OiM THE MORPHOLOGY OF CHIN IN RELATION TO VERTICAL DYSPLASIA OF CRANIOFACIAL COMPLEX (안모수직 부조화에 따른 하악이부 형태에 관한 연구)

  • Cha, Bong-Keun;Suhr, Cheong-Hoon
    • The korean journal of orthodontics
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    • v.20 no.1
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    • pp.135-156
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    • 1990
  • This study was undertaken to investigate the difference of chin morphology and mandibular form in relation to different mandibular growth direction. The subject was divided into three group i.e., control group, vertical group, and horizontal group, according to the criteria of $Bj{\ddot{o}}rk$ sum, and each group was composed of 15 females and 15 males. Medial axis analysis in addition to the routine cephalometric analysis using P.I.A.S. (personal image analysing system) was carried out to find out the differences of mandibular morphology on each group. The results were as follows: 1. The area of symphysis was larger in horizontal growth group than that of vertical growth group. 2. Protruding chin area was also larger in horizontal growth group than that of vertical growth group. 3. There was a close correlationship between protruding chin area and other form of mandible. 4. Antegonial notch depth and ramus posterior contour depth was deeper in vertical growth group than in horizontal growth group, and antegonial notch depth was more influenced by anterior part of notch than posterior part of notch. 5. Mental medial axis and incisal medial axis length, in relation to corpus medial axis length was larger in vertical growth group than in horizontal growth group.

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Anatomical Studies on the Differentiation of Reaction Tissues in Ginkgo biloba L. Seedling (은행나무 유식물에 있어서 반응조직의 분화에 대한 해부학적 연구)

  • 강경덕
    • Journal of Plant Biology
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    • v.33 no.4
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    • pp.285-292
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    • 1990
  • In order to elucidate the formation of reaction tissues during the transition from primary to secondary growth, the developmental anatomy was conducted in the first internode of Ginkgo biloba seedling in horizontal position. The righting of the horizontal first internode took place at the middle portion and gradually proceeded to the base during the primary growth. Reaction tissues were formed corresponding to the righting movement in the horizontal first internode. During the transition from primary to secondary growth, compression wood was gradually developed on the lower side only. The anatomical features of compression wood also extended longitudinally to the lower side of the vertical portion where it coincided with the lower side of the horizontal first internode occurs acropetally from basal to apical portion. Eventually, some of the anatomical features of compression wood occurred at the primary growth. And the typical compression wood is gradually established during the secondary growth. On the other hand, the lower side tracheid and ray were longer and higher than those of the upper side in the horizontal first internode. However, difference in the width of ray was not observed between the lower and upper sides.

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A Study on the Fatigue Crack Growth of Cracks in Mechanical Joints (기계적 체결부 균열의 피로균열성장에 관한 연구)

  • 허성필;양원호;정기현
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.1
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    • pp.187-194
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    • 2002
  • It has been reported that cracks in mechanical joints is generally under mixed-mode and there is critical inclined angle at which mode I stress intensity factor becomes maximum. The crack propagates in arbitrary direction and thus the prediction of crack growth path is needed to provide against crack propagation or examine safety. In order to evaluate the fatigue life of cracks in mechanical joints, horizontal crack normal to the applied load and located on minimum cross section is major concern but critical inclined crack must also be considered. In this paper mixed-mode fatigue crack growth test is performed far horizontal crack and critical inclined crack in mechanical joints. Fatigue crack growth path is predicted by maximum tangential stress criterion using stress intensity factor obtained from weight function method, and fatigue crack growth rates of horizontal and inclined crack are compared.

Mixed-Mode Fatigue Crack Growth Behavior of Cracks in Mechanical Joints Considering Critical Inclined Angle (임계 경사각을 고려한 기계적 체결부 균열의 혼합모드 피로균열성장 거동)

  • Heo, Sung-Pil;Yang, Won-Ho;Chung, Ki-Hyun;Ryu, Myung-Hai
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.187-192
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    • 2001
  • Cracks in mechanical joints is generally under mixed-mode and there is the critical inclined angle at which mode I stress intensity factor becomes maximum. In order to evaluate the fatigue life of cracks in mechanical joints, horizontal crack normal to the applied load and located on minimum cross section is major concern but critical inclined crack must also be considered. In this paper mixed-mode fatigue crack growth test is performed for horizontal crack and critical inclined crack in mechanical joints. Fatigue crack growth path is predicted by maximum tangential stress criterion using mode I and mode II stress intensity factors obtained from weight function method, and fatigue crack growth rates of horizontal and inclined crack are compared.

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Inhibitory Factors of Robinia pseudoacacia Distribution in a Pinus thunbergii Forest at the Coast (해안 곰솔림 내 아까시나무의 분포확대 억제요인)

  • Jung, Sung-Cheol;Koo, Kyo-Sang;Kim, Kyong-Ha
    • Korean Journal of Environment and Ecology
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    • v.25 no.5
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    • pp.717-724
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    • 2011
  • The objectives of this study were to analyze environment in the forest and growth characteristics for investigating the characteristics of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast. As a result of analyzing inhibitory factors of Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast, it is considered that the salt level included in a sea wind is supposed to be the primary factor of the slow growth for Robinia pseudoacacia since brown leaves, wilting and early leaf fall have appeared in the 0m spot from the artificial dune which has the high salt level. However, the soil properties and light environment hardly have a effect on the growth of Robinia pseudoacacia because there is no difference among planting places. Also, the growth ring of the horizontal root in 2year individuals 0.1~0.2m away from the dune have been formed for 1 year only as a consequence of analyzing growth rings of Robinia pseudoacacia growing on the coast. It can be infered that the nourishment of the horizontal root from individuals growing on the coast have been provided for the first 1 year only. It is estimated that, in case of the nearby areas on the coast, it is not enough to provided nourishment to the horizontal root due to obstructing the growth of new individuals by a sea wind, so the growth of the horizontal root would be hampered. Therefore, it is considered that impedient Robinia pseudoacacia distribution in a Pinus thunbergii forest at the coast is caused by making no growth of new horizontal roots and newborn individuals.

A STUDY OF THE SUTURAL FACIAL BONE GROWTH OF RABBIT : SERIAL ROENTGENOGRAPHIC STUDY BY MEANS OF MEANS OF IMPLANTS (금속매식법(金屬埋植法)에 의(依)한 가토(家兎)의 봉합성(縫合性) 안면골성장(顔面骨成長)에 관(關)한 X-선학적(線學的) 연구(硏究))

  • Lee, Won Chul
    • The korean journal of orthodontics
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    • v.9 no.1
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    • pp.23-35
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    • 1979
  • The present study has the purpose of investigating various growth and developmental aspects of rabbit snout with the aid of metallic implantation and of improving on the indirect method of growth and developmental studies of its skull. Sixty-eight growing albino rabbits were used. A head holder, film holder, cephalometer, metallic implanting device and implant materials were designed and constructed by the author. Eight metallic pins were implanted with a metallic implanting device in the rabbit snout under general anesthesia. Two metallic pins were implanted on each side of the interfrontal suture and another two were put on each side of the internasal suture near the frontonasal suture. Serial cephalograms were taken with a two-week interval, using the head holder, film holder and cephalometer. Eight items of linear measurement were obtained from the film. On the base of the results of the study, the following conclusions are obtained: 1. The metallic implant method is better than the other indirect methods for growth and developmental studies of the rabbit skull. 2. Most of the vertical growth of the rabbit snout is due to sutural growth at the frontonasal suture and the horizontal growth is at the interfrontal and the internasal suture. 3. The vertical growth of the rabbit snout is greater than the horizontal growth. 4. The horizontal growth of the rabbit snout is greater at the nasal bone than at the frontal bone. 5. The amount of vertical growth of the rabbit snout is almost same at inner and outer side of the interfrontal and internasal suture line, 6. Growth rate of the sutural growth of the rabbit snout tends to decrease by the growth of the rabbit. 7. Implant materials do not disturb growth and development of the rabbit snout, except a slight trauma effect during the first week of metallic implantation.

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The Comparison of the Physical Characteristics between Boys and Girls at Puberty (사춘기 남녀 청소년의 인체 특징에 관한 비교 - 만 $10{\sim}14$세를 중심으로 -)

  • Jeong, Hwa-Yeon;Kim, Kyung-A;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.15 no.1 s.66
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    • pp.37-57
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    • 2007
  • The purpose of this study was to analyze the body measurements of boys and girls at puberty and to provide the fundamental data for pubescent apparel manufacturers to produce clothing that reflect their physical characteristics. A total of 549 boys and 529 girls aged between 10 and 14 were measured in the capital area from March 4 to April 3, 2004. Data were collected from 35 anthropometric items and 12 photographic items per a person. SPSS Ver. 12 program was used in data analysis including means, standard deviation, t-test and Duncan test. The main results of this study were as follows. They showed the significant difference of their growth in accordance with the increase of their ages. There were also the difference between boys and girls. As for height and length items, boys showed a slow growth at the age of $10{\sim}11\;and\;12{\sim}13$. Those at the age of $11{\sim}12\;and\;13{\sim}14$ showed rapid growth. That is, an active growth was followed by a slow growth and that phenomenon repeatedly occurred. On the other hand, girls showed remarkable growth at the age $10{\sim}11$ and the growth rate gradually slowed down afterward. Regarding circumference items, boys at the age of $11{\sim}12\;and\;13{\sim}14$ showed remarkable growth. This results showed that boys at the age of $11{\sim}12$ had vertical growth and horizontal growth at the same time and for those at the age of $13{\sim}14$, growth was more conspicuous in horizontal direction. Meanwhile, for girls, the growth rate was high at the age of $11{\sim}12$, somewhat later than the age of the growth of height and length. As for breadth-related items and depth-related items, for both sexes two items grew steadily throughout the ages, breadth-related items showed a higher growth rate than that of depth-related items. This study analyzed the body measurements of pubescent boys and girls and the results showed that, for boys, an active physical growth took place at the age of 13 according to previous studies, but the findings of this study suggested that the phenomenon now occurred at the age of $11{\sim}12$, which proved that physical growth took place earlier than before. Also, an active growth was followed by a slow growth. Girls at puberty showed remarkable growth of height at the age of $10{\sim}11$ that is consistent with previous studies and then showed horizontal growth at the age of around 12, having a voluminous body shape.

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Growth of GaAs Single Crystal by Horizontal Bridgman method and Wetting (수평 Bridgman법에 의한 GaAs단결정 성장 및 Wetting에 관한 연구)

  • 강기문;홍봉식;한병성;온동만
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.35 no.1
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    • pp.1-7
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    • 1986
  • The GaAs bulk single crystals are grown by the Horizontal Bridgman method. During the growth, one of the problems in Bridgman method is the boat wetting between GaAs molten and silica boat. This boat wetting may result in another nucleation to form twin crystals. In this study, We find that the optimal size for sand blasting is 320 mesh. Backfilling the ampoule with argon gas during the vaccum bake-out decreaes the boat wetting. The reaction mechanism of Ga with quartz to produce suboxide, Ga2O, and sillion is discussed.

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Third Harmonic Generation of Shear Horizontal Guided Waves Propagation in Plate-like Structures

  • Li, Weibin;Xu, Chunguang;Cho, Younho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.36 no.2
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    • pp.149-154
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    • 2016
  • The use of nonlinear ultrasonics wave has been accepted as a promising tool for monitoring material states related to microstructural changes, as it has improved sensitivity compared to conventional non-destructive testing approaches. In this paper, third harmonic generation of shear horizontal guided waves propagating in an isotropic plate is investigated using the perturbation method and modal analysis approach. An experimental procedure is proposed to detect the third harmonics of shear horizontal guided waves by electromagnetic transducers. The strongly nonlinear response of shear horizontal guided waves is measured. The accumulative growth of relative acoustic nonlinear response with an increase of propagation distance is detected in this investigation. The experimental results agree with the theoretical prediction, and thus providing another indication of the feasibility of using higher harmonic generation of electromagnetic shear horizontal guided waves for material characterization.

Estimation of Rice Growth Using RADARSTA-2 SAR Images at Seosan Region

  • Kim, Yihyun;Hong, Sukyoung;Lee, Kyoungdo;Jang, Soyeong
    • Korean Journal of Soil Science and Fertilizer
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    • v.46 no.4
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    • pp.237-244
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    • 2013
  • Radar remote sensing is appropriate for monitoring rice because the areas where this crop is cultivated are often cloudy and rainy. Especially, Synthetic Aperture Radar (SAR) can acquire remote sensing information with a high temporal resolution in tropical and subtropical regions due to its all-weather capability. This paper analyzes the relationships between backscattering coefficients of rice measured by RADARSAT-2 SAR and growth parameters during a rice growth period. We examined the temporal variations of backscattering coefficients with full polarization. Backscattering coefficients for all polarizations increased until Day Of Year (DOY 222) and then decreased along with Leaf Area Index (LAI), fresh weight, and Vegetation Water Content (VWC). Vertical transmit and Vertical receive polarization (VV)-polarization backscattering coefficients were higher than Horizontal transmit and Horizontal receive polarization (HH)-polarization backscattering coefficients in early rice growth stage and HH-polarization backscattering coefficients were higher than VV-polarization backscattering coefficients after effective tillering stage (DOY 186). Correlation analysis between backscattering coefficients and rice growth parameters revealed that HH-polarization was highly correlated with LAI, fresh weight, and VWC. Based on the observed relationships between backscattering coefficients and variables of cultivation, prediction equations were developed using the HH-polarization backscattering coefficients.