• Title/Summary/Keyword: convex structure

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A Study on the Ancient Architecture in view of the Stone Remains (focused on the 3 Kingdom Period and Unificated Shilla Period) (석조유구(石造遺構)를 통한 한국(韓國) 고대건축(古代建築)에 관한 연구(硏究) -삼국시대와 통일신라시대를 중심으로-)

  • Cheon, Deuk-Youm;Park, Ji-Min
    • Journal of architectural history
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    • v.8 no.3 s.20
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    • pp.23-38
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    • 1999
  • The purpose of this study is to analogize the appearance of Korean Ancient Architecture in view of the Stone Remains from 3 Kingdom Period to Unificated Shilla Period. But in these period, there is no building remains but some stupas and fine arts. Especially, there are many architectural appearance and revealing signature in these Historical Stone remains. Architectural elements which are analogized by stone remains what has value as historical materials by preservation of original form from 3 Kingdom Preiod to Unificated Shilla Period are as follows : 1) Platform, the representative characteristic of Korean traditional architecture, was frame structure and accumulate structure. And circular or square footing stood a same shape column on it is put on the platform. 2) In the case of column, there used entasis column and inclined column and circular chamfer technique was applied on the top side of it. Upper side of column, capital and head pentrating tie that small bearing block was put on the center of it was joined. And longitu야nal rest(長舌) supported a cross beam. Capital and small bearing block had no bottom heel, and heel side was curved and straight. Centered bracket structure was often used, and multi bracket structure is not used yet. Inward incline technique was used. 3) Inward opening pair door which had lintel, threshold, doorjamb was usually used, Fixing stone was used for structural safety, and circular handle and lock was used for decoration. Handrail was used on the edge of wooden floor for decorative effect and safety. 4) Square rafter and circular rafter were used in the same period and so did flying rafter. Double eaves and single eave were used in the same period but, single eave was usually used. In this period, square rafter was usually used. This would be studied more by comparing with Japanese wooden architecture. 5) Hipped roof was used and half-hipped roof was not used yet. In front of th hip, there are small sculpture called Jap-Sang(雜像), and windbell was hang on the end of the hip rafter. Concave roof tile, convex roof tile, round eaver tile, decorative tile at end of roof ridge were used. Lotus style was well used on the face of roof tile for decoration. From the results of this study, wooden architecture of Unificated Shilla period was simple compare to Koryo dynasty and Chosun dynasty but, it had some brilliant character. It was hard work that analogized the form of non-existent wood architecture of Ancient Korean period by restricted stone remains. But, in addition to the results of this study and research of old documentations, more study should be go on.

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Taxonomic Implications of Seed Coat in the Subtribe Calthinae (Ranunculaceae) (미나리아재비과 동의나물아족의 종피형태와 분류학적 검토)

  • Heo, Kweon;Suh, Youngbae
    • Korean Journal of Plant Taxonomy
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    • v.38 no.1
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    • pp.1-16
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    • 2008
  • Anatomical features of seed coat were examined on Trollius, Calathodes, and Caltha of Ranunculaceae to evaluate the taxonomic circumscription of Megaleranthis saniculifolia, which is monotypic and endemic in Korea. Megaleranthis saniculifolia showed the exotestal type of seed coat exhibiting a well-developed palisade structure in exotesta and its external surface of exotesta cells was concave. On the other hand, the shape of exotesta cells in Caltha was cuboidal and the outer surface was smooth. The exotesta of Calathodes seeds was formed of the palisade structure like M. saniculifolia, but the outer surface of exotesta cells was smooth. The palisade structure was much better developed in the exotesta of Calathodes as well as Megaleranthis seeds than in the exotesta of Trollius seeds. The outer surface of exotesta cells in Trollius was either convex or concave according to the species examined. Since the genera of the subtribe Calthinae of the family display differences in seed sculpturing and the anaotmy of seed coat, these characteristics are useful to access taxonomic relationships among them. The morphological and anatomical features of seed coat suggest that Megaleranthis be possibly allied with Trollius rather than Caltha or Calathodes. Concave surface of seed coat cells and well-developed palisade structure of exotesta are shared by M. saniculifolia and some species of Trollius in common.

The Original Form and Meaning of the Gilt Bronzed Crown in Naju Bogam-ri Jeongchon Tombs (NBJ) (나주 복암리 정촌고분 금동관의 원형과 의미)

  • Yi, Gunryoung
    • Korean Journal of Heritage: History & Science
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    • v.53 no.3
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    • pp.202-223
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    • 2020
  • This purpose of this article is to identify the original form of the gilt-bronze ornamental pieces unearthed from the east part of the third wooden coffin in the Naju Bogam-ri Jeongchon (NBJ) tombs. The gilt-bronze ornamental pieces were all small, measuring less than 3cm in size and about 0.2cm in thickness, and only 19 or more small pieces were identified. In each piece of gilt decoration, a circular perforation, convex pattern, leaf-shaped spangle (瓔珞), 2 small holes for attaching spangles and gilt-bronze thread, 2 small holes for unknown purposes, and a continuous dot pattern of about 0.05 cm can be observed. As a result, it was judged that the gilt-bronze pieces excavated from the NBJ No. 1 chamber were part of the Headband Crown. Therefore, type 1 and type 3 of the gilt-bronze pieces were determined to be part of the Headband, and type 2 to be part of the Vertical Ornaments. Based on previous results, two types of restoration were proposed for NBJ No. 1 tomb gilt-bronze ornaments. In the first restoration proposal, there are wave-shaped dot patterns on the top and bottom of the crown, and the middle decoration is a spangle, circular perforation and spangle and a convex-pattern. In the second restoration plan, one row of convex patterns was added among the decorations in the middle of the first. The same type of vertical ornament was found in the Sochang (小倉) collection crown, but the overall structure and shape of the crown were completely different. On the other hand, the use of small holes of unknown use, as seen in the crown, was presumed to represent holes for fixing to a cap of organic matter. The restored NBJ No. 1 tomb gilt-bronze crown is characterized by circular punching, which makes it difficult to find an analogy in the other Three Kingdoms-period crowns. Unlike the existing halls in Gaya, Mahan, and Baekje, each district has a unique shape and decoration. The gilt-bronze crown excavated from NBJ No. 1 tomb is thought to reflect these characteristics.

Delineation of the Slip Weak Zone of Land Creeping with Integrated Geophysical Methods and Slope Stability Analysis (복합 지구물리탐사와 사면 안정해석 자료를 이용한 땅밀림 지역의 활동연약대 파악)

  • Lee, Sun-Joong;Kim, Ji-Soo;Kim, Kwan-Soo;Kwon, Il-Ryong
    • The Journal of Engineering Geology
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    • v.30 no.3
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    • pp.289-302
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    • 2020
  • To determine the shallow subsurface structure and sliding surface of land creeping in 2016 at Hadong-gun, Gyeongsangnam-do, geophysical surveys (electric resistivity, and refraction seismic methods, borehole televiewer) and slope stability analysis were conducted. The subsurface structure delineated with borehole lithologies and seismic velocity structures provided the information that the sediment layer on the top of the slope was rather as thick as 20 m and the underlying weathered rock (anorthosite) was thinner than 1 m. Based on the tension cracks observed during the geological mapping, televiewer scanning was performed at the borehole BH-2 and detected the intensive fracture zones at the ground-water level, associated with the slip weak zones mapped in dipole-dipole electrical resistivity section. Downslope sliding and slightly upward pushing at the apex of high resistive bedrock explains the curved slip plane of the land creeping. Such a convex structure might play a role of natural toe abutment for preventing the downward development of slip weak zones. In slope stability analysis, the safety factors of the slip weak zone are calculated with varying the groundwater levels for dry and rainy seasons and the downslope is founded to be unstable with safety factor of 0.89 due to fully saturated material in rainy season.

Underdetermined Blind Source Separation from Time-delayed Mixtures Based on Prior Information Exploitation

  • Zhang, Liangjun;Yang, Jie;Guo, Zhiqiang;Zhou, Yanwei
    • Journal of Electrical Engineering and Technology
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    • v.10 no.5
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    • pp.2179-2188
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    • 2015
  • Recently, many researches have been done to solve the challenging problem of Blind Source Separation (BSS) problems in the underdetermined cases, and the “Two-step” method is widely used, which estimates the mixing matrix first and then extracts the sources. To estimate the mixing matrix, conventional algorithms such as Single-Source-Points (SSPs) detection only exploits the sparsity of original signals. This paper proposes a new underdetermined mixing matrix estimation method for time-delayed mixtures based on the receiver prior exploitation. The prior information is extracted from the specific structure of the complex-valued mixing matrix, which is used to derive a special criterion to determine the SSPs. Moreover, after selecting the SSPs, Agglomerative Hierarchical Clustering (AHC) is used to automaticly cluster, suppress, and estimate all the elements of mixing matrix. Finally, a convex-model based subspace method is applied for signal separation. Simulation results show that the proposed algorithm can estimate the mixing matrix and extract the original source signals with higher accuracy especially in low SNR environments, and does not need the number of sources before hand, which is more reliable in the real non-cooperative environment.

An Experimental Study of Flow Characteristics Past vortical wall with Bottom Gap (수직벽 하부에 있는 틈새 후방의 유동특성에 관한 실험적 연구)

  • Cho Dae-Hwan;Lee Gyoung-Woo;Oh Kyoung-Gun
    • Proceedings of KOSOMES biannual meeting
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    • 2005.11a
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    • pp.153-158
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    • 2005
  • The turbulent shear flaw around a surface-mounted vertical wall was investigated using the two-frame PIV(CACTUS 3.1) system. From this study, it is revealed that at least 500 instantaneous velocity field data are required for ensemble average to get reliable turbulence statistics, but only 200 field data are sufficient for the time-averaged mean velocity information The flow has an unsteady recirculation region post vertical wall with bottom gap, followed by a slow relaxation to the fiat-plate boundary layer flow. The time-averaged reattachment length estimated from the streamline distribution is about x/H=3H. The large eddy structure in the separated shear layer seems to have signification influence on the development of the separated shear layer and the reattachment process.

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BUCCAL FAT PAD TRANSFER AS A PEDICLED FLAP FOR FACIAL AUGMENTATION (외상성 안면 함몰부에 협지방대 유경 피판을 사용한 재건술)

  • Chung, Sang-Chul;Ann, Heui-Yong;Choi, Hong-Sik;Um, In-Woong;Kim, Chang-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.13 no.2
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    • pp.153-159
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    • 1991
  • The use of the autogenous free fat is a well-known procedure to fill in superficial depressions resulting from the traumatic or congenital defects. The major donor site for this procedure was the abdominal subcutaneous fat or buttocks. In 1977, Egyedi was the first to report the use of the buccal fat pad as a pedicled graft. The buccal fat pad is a structure usually considered to be a nuisance when encountered in intraoral procedures such as facial bone osteotomies, elevation of buccal falp, or procedures on Stensen's duct. In these operations, appearance of the buccal fat pad complicates surgical exposure. The buccal fat pad is a lobulated convex mass of fatty tissue covered by a very delicate membrane, and is described as having a body from which four processes extend. These projection serve as a filling material between the various muscular structures in the area. Recently malar depression was augmented with the pedicled buccal fat pad in 3 cases, and it was used for the reconstruction of the nasolabial fold in one case.

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Ultrasensitive laser interferometer for precision measurement of small vibration displacement (고감도 레이저 간섭계를 이용한 미소 진동 진폭의 정밀측정)

  • 서상준
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.3
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    • pp.440-449
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    • 1988
  • Small vibration displacements may be measured by optical interferometers, based on the Michelson method. The standard Michelson interferometer works well when the mirror displacements are relatively large compared to the optical wavelength. But it does not work for displacements less than approximately a quater of optical wavelength. Several multiple reflection laser interferometers, simply modified standard Michelson interferometer, have been developed to decrease the minimum detectable limits. Among these a relatively simple and easy multiple reflection system is used to measure the small vibration displacements. This multiple reflection system is constructed with a right angle prism and a convex lens. Therefore this system makes it possible to measure a vibration displacement of the small area on the vibrating structure. The fringe interpolation method and curve fitting method are used to determine accurately the small vibration displacements from the measured interference fringe patterns. Also computer simulation technique is used to check the accuracies of these method. According to the results of the computer simulation technique, the curve fitting method is more accurate than the fringe interpolation method. The optically measured results are in good agreement with those of the standard accelerometer with high accuracy and it is possible to measure the peak vibration displacement as small as 9.01nm using multiple reflection system and curve fitting method.

Design and Fabrication of Linear-Array Ultrasonic Transducer Using KLM and FEM Simulation for Non-Destructive Testing (KLM 및 FEM 시뮬레이션을 이용한 비파괴검사용 선형배열 초음파 탐촉자의 설계 및 제작)

  • Park, Chan-Yuk;Sung, Jin-Ho;Jeong, Jong-Seob
    • Journal of the Korean Society for Nondestructive Testing
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    • v.35 no.2
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    • pp.120-127
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    • 2015
  • In this paper, a linear-array transducer capable of overcoming the faults of a single element and phased array transducers with convex shape for non-destructive ultrasonic testing was designed and fabricated. A 5.5 MHz linear-array transducer was designed using the PiezoCAD program based on the KLM analysis and the PZFlex program based on the FEM analysis. A 2-2 composite structure was employed to achieve broad-band characteristics. A 128 element linear-array transducer was fabricated and its performance was compared with the simulation results. The center frequency of the fabricated transducer was 5.5 MHz and the -6 dB frequency bandwidth was 70 %. Thus, we expect that the designed transducer can provide an effective inner image of the test material during non-destructive ultrasonic testing.

A Study on Formative Characteristic of Subculture Style in 20C Fashion -Focused on Hair Style - (20세기 패션에 나타난 하위문화 스타일의 조형성에 관한 연구 - 헤어스타일을 중심으로-)

  • Kim, Jeong-Mee;Seol, Yu-Jin
    • Fashion & Textile Research Journal
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    • v.8 no.2
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    • pp.225-232
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    • 2006
  • This study purposed to review the concept and characteristics of subculture theoretically and then to analyze subcultural hairstyles shown in the 20th century's fashion in terms of form, structure, texture, design line and design principle, which were formative factors of beauty art. The range of this study was from the 1950's to the 1990's, during which subcultural hairstyles, which were selected for this study, kept a unique formality as subcultural characteristics of each time were reflected in hairstyles. The hairstyles found in subcultural styles were reviewed as follows. From the formative analysis as the above, it was concluded that layer form was seen most frequently in the subcultural hairstyles. This may be because it has a lot of layers in hair, and enables to make more various forms with a simpler care than other hairstyles so that it is easy to show one's own characteristic or differentiate oneself from others. Thanks to the characteristics of layer form, horizontal and convex were often seen as design lines. As for a texture, straight often appeared. The texture of straight is naturally formed without any care applied on hair. The reason may be that most subcultures refused artificiality. Therefore, the characteristics of subcultural hairstyles may be that hairstyles are transformed into various forms and created into the styles appropriately for individual tastes so as to clearly express one's own idea and thought.