• Title/Summary/Keyword: Embedded post

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Effects of Design Parameters of Steel-Embedded Precast Composite Piers (강재매입형 조립식 합성교각의 설계 변수 영향)

  • Shim, Chang-Su;Lim, Hyun-Sik;Chung, Young-Soo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.53-54
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    • 2009
  • Steel-embedded composite piers provide flexible design alternatives to satisfy the required performance due to various design parameters of composite sections. For the fast construction of composite piers, bolt connection can be utilized for small size piers and post-tensioning to the pier segments for the large size piers. In this paper, experimental results on composite piers were investigated to evlauate the effects of design parameters on the behavior of composite piers. Appropriate sections and their integration methods were suggested according to the design conditions. For the modular construction of bridge piers, pier segments need to be divided considering their weight and careful considerations on details to adjust fabrication and construction error. Connection details for the pier cap were also proposed.

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Static behaviour of bolted shear connectors with mechanical coupler embedded in concrete

  • Milosavljevic, Branko;Milicevic, Ivan;Pavlovic, Marko;Spremic, Milan
    • Steel and Composite Structures
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    • v.29 no.2
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    • pp.257-272
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    • 2018
  • The research of shear connectors composed from mechanical couplers with rebar anchors, embedded in concrete, and steel bolts, as a mean of shear transfer in composite connections is presented in the paper. Specific issues related to this type of connections are local concrete pressure in the connector vicinity as well as the shear flow along the connector axis. The experimental research included 18 specimens, arranged in 5 series. Nonlinear numerical analyses using Abaqus software was conducted on corresponding FE models. Different failure modes were analysed, with emphasis on concrete edge failure and bolt shear failure. The influence of key parameters on the behaviour of shear connector was examined: (1) concrete compression strength, (2) bolt tensile strength and diameter and (3) concrete edge distance. It is concluded that bolted shear connectors with mechanical couplers have sufficient capacity to be used as shear connectors in composite structures and that their behaviour is similar to the behaviour of post installed anchors as well as other types of connectors anchored without the head.

WLP and New System Packaging Technologies

  • WAKABAYASHI Takeshi
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2003.11a
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    • pp.53-58
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    • 2003
  • The Wafer Level Packaging is one of the most important technologies in the semiconductor industry today. Its primary advantages are its small form factor and low cost potential for manufacturing including test procedure. The CASIO's WLP samples, application example and the structure are shown in Fig.1, 2&3. There are dielectric layer , under bump metal, re-distribution layer, copper post , encapsulation material and terminal solder .The key technologies are 'Electroplating thick copper process' and 'Unique wafer encapsulation process'. These are very effective in getting electrical and mechanical advantages of package. (Fig. 4). CASIO and CMK are developing a new System Packaging technology called the Embedded Wafer Level Package (EWLP) together. The active components (semiconductor chip) in the WLP structure are embedded into the Printed Wiring Board during their manufacturing process. This new technical approach has many advantages that can respond to requirements for future mobile products. The unique feature of this EWLP technology is that it doesn't contain any solder interconnection inside. In addition to improved electrical performance, EWLP can enable the improvement of module reliability. (Fig.5) The CASIO's WLP Technology will become the effective solution of 'KGD problem in System Packaging'. (Fig. 6) The EWLP sample shown in Fig.7 including three chips in the WLP form has almost same structure wi_th SoC's. Also, this module technology are suitable for RF and Analog system applications. (Fig. 8)

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Design of Graphic Generator for Driving HUD(Head-Up Display) and MFD(Multi-Function Display) (전방시현기 및 다기능시현기 구동을 위한 그래픽 영상생성기 설계 연구)

  • 황상현;이재억;박덕배
    • Journal of the Korea Institute of Military Science and Technology
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    • v.5 no.2
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    • pp.72-82
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    • 2002
  • This paper presents the design technology of a Graphic Generator which drives the embedded aircraft display equipments such as HUD(Head-Up Display) and MFD (Multi-Function Display) those provide pilot with the most important mission information. The main issue of this design is how we can implement the real-time embedded graphic generator using a general purpose processor as a substitute for the obsolete the production of specific graphic processor in the military market. So we proposed two kinds of method that one is a software solution so called graphic kernel system, interpreting the display file, controlling the graphic system and pre-processing graphic primitives, the other is a hardware solution so called graphic engine, interpreting passed commands through the graphic kernel system, post-processing the looping calculation taking much of time as implemented by software. We have tested and verified the functionalities and the required performance of Graphic Generator.

Fabrication of low temperature metal dot nano-floating gate memory using ELA Poly-Si thin film transistor (Poly-Si 기판을 이용한 저온 공정 metal dot nano-floating gate memory 제작)

  • Koo, Hyun-Mo;Shin, Jin-Wook;Cho, Won-Ju;Lee, Dong-Uk;Kim, Seon-Pil;Kim, Eun-Kyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.120-121
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    • 2007
  • Nano-floating gate memory (NFGM) devices were fabricated by using the low temperature poly-Si thin films crystallized by ELA and the $In_2O_3$ nano-particles embedded in polyimide layers as charge storage. Memory effect due to the charging effects of $In_2O_3$ nano-particles in polyimide layer was observed from the TFT NFGM. The post-annealing in 3% diluted hydrogen $(H_2/N_2)$ ambient improved the retention characteristics of $In_2O_3$ nano-particles embedded poly-Si TFT NFGM by reducing the interfacial states as well as grain boundary trapping states.

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An Experimental Study on the Shear Failure Behavior of Post-installed Set Anchor for Concrete (콘크리트용 후설치 세트앵커의 전단파괴거동에 관한 실험적 연구)

  • Um, Chan-Hee;Yoo, Seung-Woon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.2
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    • pp.367-375
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    • 2014
  • Recently the use of concrete post-installed set anchors has been increasing because this constructing method is flexible and easy to attach or fix structural members when we repair, reinforce, or remodel a concrete structures. Depending on the shear strength of steel, the strength of concrete, edge distance and anchor interval, etc, the anchor loaded in shearing exhibits various failure modes such as steel failure, concrete failure, concrete pryout. In this study, the objective is to investigate the effects of the variations like anchor embedment depth, anchor interval, edge distance and concrete strength on the shear failure behavior of post-installed concrete set anchor embedded in concrete. The results of embedment depth experiments show that concrete strength has much effection on the shallow embedment depth. Steel failure occur to all results of the anchor interval experiments, but concrete is failed when edge distance experiments that less than the embedment depth. Through the comparision of the same parameters experiments results show that as strong as concrete strength are the displacement results are small.

Detection of tension force reduction in a post-tensioning tendon using pulsed-eddy-current measurement

  • Kim, Ji-Min;Lee, Jun;Sohn, Hoon
    • Structural Engineering and Mechanics
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    • v.65 no.2
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    • pp.129-139
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    • 2018
  • Post-tensioning (PT) tendons are commonly used for the assembly of modularized concrete members, and tension is applied to the tendons during construction to facilitate the integrated behavior of the members. However, the tension in a PT tendon decreases over time due to steel corrosion and concrete creep, and consequently, the stress on the anchor head that secures the PT tendon also diminishes. This study proposes an automatic detection system to identify tension reduction in a PT tendon using pulsed-eddy-current (PEC) measurement. An eddy-current sensor is installed on the surface of the steel anchor head. The sensor creates a pulsed excitation to the driving coil and measures the resulting PEC response using the pick-up coil. The basic premise is that the tension reduction of a PT tendon results in stress reduction on the anchor head surface and a change in the PEC intensity measured by the pick-up coil. Thus, PEC measurement is used to detect the reduction of the anchor head stress and consequently the reduction of the PT tendon force below a certain threshold value. The advantages of the proposed PEC-based tension-reduction-detection (PTRD) system are (1) a low-cost (< $ 30), low-power (< 2 Watts) sensor, (2) a short inspection time (< 10 seconds), (3) high reliability and (4) the potential for embedded sensing. A 3.3 m long full-scale monostrand PT tendon was used to evaluate the performance of the proposed PTRD system. The PT tendon was tensioned to 180 kN using a custom universal tensile machine, and the tension was decreased to 0 kN at 20 kN intervals. At each tension, the PEC responses were measured, and tension reduction was successfully detected.

An Experimental Study on the Pullout Failure Behavior of Post-installed Concrete Set Anchor (후설치 콘크리트 세트앵커의 인발파괴거동에 관한 실험적 연구)

  • Suth, Ratha;Yoo, Seung-Woon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.1
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    • pp.40-47
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    • 2014
  • Recently the use of concrete post-installed set anchors has been increasing because this constructing method is flexible and easy to attach or fix structural members when we repair, reinforce, or remodel structures. Accordingly, designers and builders of Korea depend on foreign design codes since there are no exact domestic anchor design codes that they could credit. The anchor in plain concrete loaded in tensile exhibits various failure modes such as concrete breakout, splitting, steel failure, pull-out and side-face blowout, that depending on the tensile strength of the steel, the strength of concrete, embedment depth, interval, the edge distance and the presence of adjacent anchor. The objective is to investigate the effects of the variations like anchor embedment depth, interval and edge distance on pull-out fracture behavior of post-installed concrete set anchor embedded in plain concrete.

Study on Internalization of Post-IMF Era's Competition Logic - Focusing on the Changes of Survival Program Since IMF Era (포스트 IMF 시대 경쟁 논리의 내면화 양상 연구 - IMF 이후 서바이벌 프로그램의 변화 양상을 중심으로)

  • Park, In-Seong
    • The Journal of the Korea Contents Association
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    • v.19 no.2
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    • pp.591-604
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    • 2019
  • This study examines the process of internalization and elaboration of the logic of competition in the post-IMF era through the genealogy of the survival program. Post-IMF is based on disaster reality, which reveals a specific emotional structure related to the competition, if the narrative of overcoming the IMF event finds narrative models that can be sufficiently reconciled between communityism and individual success. This study also examines the process of disaster preparedness through survival form and narrative structure embedded in such form. Thus, this study reconstructed the diachronic change to track the change of the survival program and the subsequent narrative change. Relative to the time of the healing-mentor, the survival program seems to be declining, but rather seems to have created a new transition through the logic of self-development contained in the healing-mentoring discourse. this logic leads to be ghettoized hierarchy of preferences. Now, the survival program is to perform fantastic surrogate satisfaction by delegating competition to a narrow self-directed area rather than to a big empathy within the community.

Embedded Fingerprint Verification Algorithm Using Various Local Information (인근 특징 정보를 이용한 임베디드용 지문인식 알고리즘)

  • Park Tea geun;Jung Sun kyung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4C
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    • pp.215-222
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    • 2005
  • In this paper, we propose a fingerprint verification algorithm for the embedded system based on the minutia extracted using the image quality, the minutia structure, and the Sequency and the orientation of ridges. After the pre- and the post-processing, the true minutia are selected, thus it shows high reliability in the fingerprint verification. In matching process, we consider the errors caused by shift, rotation, and pressure when acquiring the fingerprint image and reduce the matching time by applying a local matching instead of a full matching to select the reference pair. The proposed algorithm has been designed and verified in Arm920T environment and various techniques for the realtime process have been applied. Time taken from the fingerprint registration through out the matching is 0.541 second that is relevant for the realtime applications. The FRR (False Reject Rate) and FAR (False Accept Rate) show 0.079 and 0.00005 respectively.