• Title/Summary/Keyword: curved type

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Test Construction of the Paved Track at Subway Main Line (도시철도 본선 토공구간에서의 포장궤도 시험부설)

  • Lee, Il-Wha;Kang, Yun-Suk;Kong, Sun-Yong;Kim, Sang-Jin;Lee, Shun-Gu;Jung, Yun-Sik
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1689-1694
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    • 2008
  • Recently, the development of the paved track is required as a low-maintenance of conventional line. The main reason is that the line capacity and bearing of track are increased progressively. The important factors of paved track are stability and applicability. To be based on this subject, cement mortar pouring type paved track is developed. The paved track is a kind of concrete track using the prepacked concrete technique. The most important thing to design the paved track is to optimize the track structure and materials considering various conditions. Until now, the paved track is verified a various material and structure test. In this paper, it is introduce to the test construction at the urban subway main line. The test construction is completed at Dec. 2007. A major object and substance is a guarantee of construction progress on main line, track performance, construction technique for curved section, transition zone and winter season, recycling the used ballast and application of specific sleeper for sharp curved section.

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Estimation of Optimum Pile length Using Various Prediction (다양한 예측기법을 이용한 현장타설말뚝의 최적길이 산정)

  • Choi, Young-Seok;Iim, Hyung-Joon;Song, Myung-Jun;Jang, Hak-Sung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.700-707
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    • 2008
  • As plan connecting island to island or island to land is needed, a lot of long-span bridge is being designed lately in Southern part of Korea. With development of pile equipment, overhanging large-scaled concrete pile are adopted to foundation type of main tower or pylon. About the number of 15~30 group piles per tower foundation is designed to resist long-spaning super-structure load, but by restricted condition of site investigation cost, a few boring-hole tests are performed to identify sub-ground layers. Up to now, direct-curved method connecting two or three known boring logs and representative interval method are usually used to evaluate unknown depth and rock properties at locations where piles are constructed. Because this approach is not logical and so rough, much difference occurs between designed length of piles and real length of it. In this paper, using a lot of various prediction method(reciprocal distance method, inverse square distance method and kriging method etc.), we suggest optimum length of group piles.

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Study on Multi-point Dieless Forming Technology Based on Numerical and Experimental Approach (수치 및 실험적 접근을 통한 다점무금형성형기술 연구)

  • Heo, S.C.;Seo, Y.H.;Ku, T.W.;Song, W.J.;Kim, J.;Kang, B.S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.220-223
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    • 2008
  • Large curved plate blocks are widely used to construct hull structure in shipbuilding industry. Most curved plates are manufactured by using manual method called as line heating that use deformation caused by residual stress after local heating along a line which is perpendicular to the curvature direction. However, its working environment is poor and its formability is totally dependent on an experienced technician. In view of that, multi-point dieless forming (MDF) technology that use reconfigurable punch arrays instead of one piece die is proposed in this study. The MDF process is based on a concept of equivalent die surface made by numbers of punches which has round tip at the end of it. In this study, numerical simulation for common curvature type such as saddle shape was carried out. In addition, experiments in the plate forming process were also conducted to compare with the numerical results in view of final configuration. Consequently, it was noted that the proposed dieless forming method has considerable feasibility to substitute the new process for conventional manual method.

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Numerical Analysis of Flow Uniformity in Selective Catalytic Reduction (SCR) Process Using Computational Fluid Dynamics (CFD)

  • Shon, Byung-Hyun
    • International Journal of Advanced Culture Technology
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    • v.10 no.3
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    • pp.295-306
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    • 2022
  • The NOx removal performance of the SCR process depends on various factors such as catalytic factors (catalyst composition, shape, space velocity, etc.), temperature and flow rate distribution of the exhaust gas. Among them, the uniformity of the flow flowing into the catalyst bed plays the most important role. In this study, the flow characteristics in the SCR reactor in the design stage were simulated using a three-dimensional numerical analysis technique to confirm the uniformity of the airflow. Due to the limitation of the installation space, the shape of the inlet duct was compared with the two types of inlet duct shape because there were many curved sections of the inlet duct and the duct size margin was not large. The effect of inlet duct shape, guide vane or mixer installation, and venturi shape change on SCR reactor internal flow, airflow uniformity, and space utilization rate of ammonia concentration were studied. It was found that the uniformity of the airflow reaching the catalyst layer was greatly improved when an inlet duct with a shape that could suppress drift was applied and guide vanes were installed in the curved part of the inlet duct to properly distribute the process gas. In addition, the space utilization rate was greatly improved when the duct at the rear of the nozzle was applied as a venturi type rather than a mixer for uniform distribution of ammonia gas.

Tegumental Ultrastruetures of Echinostoma hoytense observed by Scanning Electron Microscopy (Echinostoma hortense 표피의 주사전자현미경적 관찰)

  • 이순형;홍성종
    • Parasites, Hosts and Diseases
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    • v.24 no.1
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    • pp.63-70
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    • 1986
  • The tegumental ultrastructures oi Echinostoma hortense adults were observed by scanning electron microscopy. The worms of 4 weeks of age were harvested from albino rats experimentally infected with the metacercariae obtained from the loach. The results were as follows: 1. The worms were leaf-like and their anterior end portion, including oral sucker and head crown, ventrally curved to face posteriorly. The tegument of whole body was wrinkled transversely and covered with cobblestone-like cytoplasmic processes. 2. The oral sucker had roundly swollen (type I ) sensory papillae on the ventral half of its lip and mini-ciliated knob-like (type I ) sensory papillae, arranged in 2∼3 rows, on the dorsal outer surface. 3. Aspinous ventral sucker had many of type I papillae arranged in a circular band on its outer surface. The tegument around the genital opening was of similar feature to the ventral sucker, but sensory papillae were hardly found around the former. 4. Scale-like spines with broad base and round tip were distributed densely on the tegument anterior to the ventral sucker but they became sparse in posterior half of the ventral surface, finally to disappear at posterior extremity. A few number of type I papillae were observed on the ventral surface. The results suggest that the tegument of 5. hortense is similar to that of other echinostomes etapecially 5. revolutum. But the number and arrangement of collar spines, and/or the type and distribution of sensory papillae seem characteristic features of E. hortense differed from other echinostomes.

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A Study on the Cognitive Characteristics and Image Formation Structure of Hotel Access Space (호텔 진입공간의 유형별 인지특성 및 이미지형성구조에 관한 연구)

  • Lee, Jeong-Lim;Cho, Yong-Joon
    • Journal of the Korean housing association
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    • v.20 no.5
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    • pp.9-21
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    • 2009
  • This study classified visual perception types of access space at 17 five-star hotels in Jejudo and examined their cognitive characteristics and image formation structures in an effort to provide basic information important for designing the elevation and the access spaces of a hotel. The results of this study are as follows. Access space image of experimental hotels showed more negative evaluations at both city hotels and resort hotels, viewing angle (upward angle) was also positively evaluated between $10^{\circ}{\sim}12^{\circ}$ and $18^{\circ}$ and central type in arrangement type and detour access and straight access types in access circulation type were positively evaluated. When viewed from an upward angle of $10^{\circ}$ to $12^{\circ}$, the most important factors were as plasticity, decorativeness, and creativity; from $18^{\circ}$ it was such factors as harmony and peculiarity; and at $45^{\circ}$ it was factors like decorativeness and stability. In considering the various access types, the most important factors in a straight access type were peculiarity and harmony; for one-time curved access type it was by decorativeness, creativity, Peculiarity, and stability; and for detour access types it was decorativeness, stability, and peculiarity. Influential of factors affecting image formation and plasticity and harmony factors and the form had more influences on image formation.

BER performance analysis by angle spreading effect in the DoA estimation and beam-forming using 3D phase array antenna (3D 위상 배열 안테나를 이용한 DoA 추정과 빔 형성시 각도 퍼짐에 의한 BER 성능 분석)

  • Lim, Seung-Gag;Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.2
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    • pp.137-144
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    • 2009
  • This paper deals with the performance comparison of jammer signal's angle spreading in the beamforming after the estimation of direction of arrival using 3D array antenna basis of the GPS signal. After the estimation of direction of arrival using array antenna, the beamforming is need for the direction of arrival by spatial filtering and the other direction are nulling for reducing intererence signal, it is possible to improving the received signal strength and quality. But we obtains the degraded performance by the angle spreading due to the multi-jammer signal in this process. In this paper, the MUSIC and LCMV algorithms are applied for the estimating the direction of arrival and for beamforming using the 5 types of 3D array antenna. we performs the comparison of performance by calculating the bit error rate applying the BPSK modem and the varying the azimuth and elevation angle of incoming jammer signal. As a result of simulation, the Curved (B) type 3D array antenna has a more better performance compared to the other type antenna.

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Practicability Strength Assessment of a Bone Metallic Plate at the Femur Fixation (대퇴골(Femur)고정용 골 금속판 제작 및 강도 평가)

  • Kim, Jeong-Lae;Ahn, Chang-Sik;Seo, Byoung-Do
    • Journal of the Ergonomics Society of Korea
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    • v.27 no.2
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    • pp.83-89
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    • 2008
  • Study was developed the metallic plate for fixation in the femur fracture and plates has a firm place in fracture treatment. This plates can be stabilized for fracture fixation as well as biological and dynamical device. The device's designation and sizing has a optimization with bending structural stiffness and strength, known meaning that is reliable regardless of the plate by the short type and long type. The bending strength of the curved metallic long plate has to evaluate a 11,000N and the bending strength of the curved metallic short plate has to evaluate a 6,525N. This see the X-ray image of bending angle made certain of 15$^{\circ}$ at number 2 and same 82.87$^{\circ}$ at number 2, 4, 5, 7, 8, 9, 10 by outside angle, and confirmed 25.26$^{\circ}$ at number 3, 3.68$^{\circ}$ at number 6, 15.64$^{\circ}$ at number 9 by inside angle. This study shows that keep up the metallic plate for fixation in the femur fracture through X-ray Image and the device can be used to support Revision case of Hip Implant and to use a case of Hip screw compression of Hip Neck Fracture. Short plate have a wrapping of femur and long plate have to preserve a pole of femur.

A study on the DoA Estimation Prformance of Interference Signal in W-CDMA using 3D Adaptive Array Antenna (W-CDMA에서 3차원 적응 배열 안테나를 이용한 방해 신호의 도래각 추정 성능에 관한 연구)

  • Lim, Seung-Gag;Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.1
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    • pp.11-17
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    • 2009
  • This paper deals with the estimation performance DoA (Direction of Arrival) using the 3D adaptive array antenna in W-CDMA signal. For this, we proposed the 5 types of 3D array antenna, and appied for the MUSIC in order to the estimation of DoA algorithm for that antenna, commonly, then the DoA estimation error was used for the estimation performance. In the mobile communication and radio positioning service, performing the spatial filtering after the DoA estimation in array antenna, the quality of receiving signal can improve by the nulling or minimization of interfering signal which is from the undesired direction and the forming of beam which is from the desired direction. The result of DoA estimation and the DoA estimation error by varying the signal to noise ration and the number of interfering signal and power of each type antenna was calculated by computer simulation. As a result of simulation, the other propose antenna has good performance excluding the stack 3D antenna in DoA estimation and the Curved-B type antenna has more superior performance when increasing the number of interfering signal and power in the DoA estimation error.

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Chinese Po corresponding to Jikryung of Chosun Era - Focusing on Yesal and Jikshin - (조선시대 直領과 관련있는 중국의 袍制 -예살과 직신을 중심으로 -)

  • 이주영;권영숙
    • Journal of the Korean Society of Costume
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    • v.50 no.6
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    • pp.127-142
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    • 2000
  • The names of Chinese Po corresponding to Korean Jikryung are Yesal and Jikshin. Thus the purpose of this paper is to review of the shapes and usage of Yesal and Jikshin and then make a comparative review between the twos and Jikryung having side Moo. Results of the study are described as follows : 1. The Chinese costume, Yesal is translated literally into Korean, Euisal or Euisal Jikryung and called Euisal Diknyung or Uisakot in Korean while Jikshin is translated into Korean, Jikryung and called Diknyung. 2. Yesal is a new type of clothing as created during the Ming period. The costume is the remnant type of Yosunoja and Byunsunoja in the periods of Sung and Yuan. Types of Yesal are classified into two, or one whose rear part's upper and lower areas are connected with each other and whose front part's upper and lower areas are net, the other in which those upper and lower areas are disconnected both in front and rear parts. 3. Types of Jikshin are classified into two, one having Pa and the other having loot. The latter is re-classified into two, one whose sleeve is large and wide, the whole length of which is long and which was usually worn by Sain, and the other whose sleeve is small and narrow, the whole length of which is short and which was by the grass root. 4. Yesal and Jikryung both having Pa have the almost same shapes except their front parts. Baerae of the former is more curved than that of the latter. Also the both were used as official uniforms worn by civil and military officials from higher to lower levels. 5. Jikshin and Jikryung both having Pa have the same shapes. Baerae of the former is more curved than that of the latter. The both were used as official uniforms worn by civil and military officials under a King and as casual costumes by Sadaeboo. In terms of color, Jikshin and Jikryung both employed red, blue and green, Especially the red color was favorably used both in China and Chosen at that time.

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