• 제목/요약/키워드: laboratory method

검색결과 7,999건 처리시간 0.042초

Geometrically nonlinear meshfree analysis of 3D-shell structures based on the double directors shell theory with finite rotations

  • Mellouli, Hana;Jrad, Hanen;Wali, Monther;Dammak, Fakhreddine
    • Steel and Composite Structures
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    • 제31권4호
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    • pp.397-408
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    • 2019
  • In this paper, a geometrically nonlinear meshfree analysis of 3D various forms of shell structures using the double director shell theory with finite rotations is proposed. This theory is introduced in the present method to remove the shear correction factor and to improve the accuracy of transverse shear stresses with the consideration of rotational degrees of freedom.The present meshfree method is based on the radial point interpolation method (RPIM) which is employed for the construction of shape functions for a set of nodes distributed in a problem domain. Discrete system of geometrically nonlinear equilibrium equations solved with the Newton-Raphson method is obtained by incorporating these interpolations into the weak form. The accuracy of the proposed method is examined by comparing the present results with the accurate ones available in the literature and good agreements are found.

실내모형시험을 통한 지반혼합 및 주입공법의 노후저수지 차수 보강성능 비교 연구 (A Comparative Study on the Impermeability-reinforcement Performance of Old Reservoir from Injection and Deep Mixing Method through Laboratory Model Test)

  • 송상훤
    • 한국농촌건축학회논문집
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    • 제24권2호
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    • pp.45-52
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    • 2022
  • Of the 17,106 domestic reservoirs(as of December 2020), 14,611 are older than 50 years, and these old reservoirs will gradually increase over time. The injection grouting method is most applied to the reinforcement method of the aging reservoir. However, the injection grouting method is not accurate in uniformity and reinforced area. An laboratory model test was conducted to evaluate the applicability of the deep mixing method, which compensated for these shortcomings, as a reservoir reinforcement method. As a result of calculating the hydraulic conductiveity for each method through the model test results, the injection grouting method was calculated as a hydraulic conductiveity value that was about 7.5 times larger than that of the deep mixing method. As a result of measuring the water level change in the laboratory model test, it was found that the water level change decreased in the injection method and deep mixing method compared to the non-reinforcement method. In addition, deep mixing method showed a water level change of about 15% based on 40 hours compared to the injection method, indicating that the water-reducing effect was superior to that of the injection method.

A Turbidimetric Determination of Protein by Trichloroacetic Acid

  • Choi, Wahn-Soo;Chung, Kae-Jong;Chang, Man-Sik;Chun, Jae-Kwang;Lee, Hyang-Woo;Hong, Sung-Youl
    • Archives of Pharmacal Research
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    • 제16권1호
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    • pp.57-61
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    • 1993
  • Based on the turbidimetric response of protein with 50% trichloroacetic acid (TCA), this study aims to introduce an assay method for protein in solution. The standard procedure consists of mixing equal volume of sample solution (standard or unknown) with 50%-TCA solution and measuring the absorbance at 450 nm after 20 min. The absorbances of the solutions were almost stable over 120 min at room temperature. This assy method is simple, reproducible, and tolerant to many interfering substances. It can detect less amount than $10\mu$g/ml of bovin serum albumin. The assay method has low protein-to-protein variability over wide range of molecular weight.

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A Novel Reconfigurable Processor Using Dynamically Partitioned SIMD for Multimedia Applications

  • Lyuh, Chun-Gi;Suk, Jung-Hee;Chun, Ik-Jae;Roh, Tae-Moon
    • ETRI Journal
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    • 제31권6호
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    • pp.709-716
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    • 2009
  • In this paper, we propose a novel reconfigurable processor using dynamically partitioned single-instruction multiple-data (DP-SIMD) which is able to process multimedia data. The SIMD processor and parallel SIMD (P-SIMD) processor, which is composed of a number of SIMD processors, are usually used these days. But these processors are inefficient because all processing units (PUs) should process the same operations all the time. Moreover, the PUs can process different operations only when every SIMD group operation is predefined. We propose a processor control method which can partition parallel processors into multiple SIMD-based processors dynamically to enhance efficiency. For performance evaluation of the proposed method, we carried out the inverse transform, inverse quantization, and motion compensation operations of H.264 using processors based on SIMD, P-SIMD, and DP-SIMD. Experimental results show that the DP-SIMD control method is more efficient than SIMD and P-SIMD control methods by about 15% and 14%, respectively.

The Injection of PDLC Solution Mixture in a Reduced Pressure

  • Kim, Kang-Pil;Yang, Kee-Jeong;Kim, Dae-Hwan;Choi, Byeong-Dae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.524-526
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    • 2007
  • Polymer dispersed liquid crystal (PDLC) films consist of micro-droplets of liquid crystals dispersed in a polymer matrix. To make wide area PDLC filled devices, it is necessary to develop reliable method of vacuum injection of PDLC solution instead of the capillary injection. However, well-known 2-ethylhexylacrylate (EHA), main element of a prepolymer, exhibits the volatility problems, when the PDLC solution is placed under the low pressure. In this study, we developed the vacuum injection process to fill a wide area cell. Experimental results indicate that the $V_{90}$(turn-on voltage) of the PDLC cell made by a vacuum injection method are lower than that of the PDLC cell made by a capillary injection method.

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Extension of a semi-analytical approach to determine natural frequencies and mode shapes of a multi-span orthotropic bridge deck

  • Rezaiguia, A.;Fisli, Y.;Ellagoune, S.;Laefer, D.F.;Ouelaa, N.
    • Structural Engineering and Mechanics
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    • 제43권1호
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    • pp.71-87
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    • 2012
  • This paper extends a single equation, semi-analytical approach for three-span bridges to multi-span ones for the rapid and precise determination of natural frequencies and natural mode shapes of an orthotropic, multi-span plate. This method can be used to study the dynamic interaction between bridges and vehicles. It is based on the modal superposition method taking into account intermodal coupling to determine natural frequencies and mode shapes of a bridge deck. In this paper, a four- and a five-span orthotropic roadway bridge deck are compared in the first 10 modes with a finite element method analysis using ANSYS software. This simplified implementation matches numerical modeling within 2% in all cases. This paper verifies that applicability of a single formula approach as a simpler alternative to finite element modeling.

보존 경계 사각형을 이용한 이동객체의 현재와 미래 위치 색인 (Indexing for current and future positions of moving objects using new conservative bounding rectangle)

  • Hoang Do Thanh Tung;Jung, Young-Jin;Lee, Eung-Jae;Ryu, Keun-Ho
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2003년도 가을 학술발표논문집 Vol.30 No.2 (2)
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    • pp.43-45
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    • 2003
  • Nowadays, with numerous emerging applications (e.g., traffic control, meteorology monitoring, mobile computing, etc.), access methods to process current and future queries for moving objects are becoming increasingly important. Among these methods, the time-parameterized R-tree (TPR-tree) seems likely the most flexible method in one, two, or three-dimensional space. A key point of TPR-tree is that the (conservative) bounding rectangles are expressed by functions of time. In this paper, we propose a new method, which takes into account positions of its moving objects against the rectangle's bounds. In proposed method, the size of bounding rectangle is significantly smaller than the traditional bounding rectangle in many cases. By this approach, we believe that the TPR-tree can improve query performance considerably.

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Mobile Palmprint Segmentation Based on Improved Active Shape Model

  • Gao, Fumeng;Cao, Kuishun;Leng, Lu;Yuan, Yue
    • Journal of Multimedia Information System
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    • 제5권4호
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    • pp.221-228
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    • 2018
  • Skin-color information is not sufficient for palmprint segmentation in complex scenes, including mobile environments. Traditional active shape model (ASM) combines gray information and shape information, but its performance is not good in complex scenes. An improved ASM method is developed for palmprint segmentation, in which Perux method normalizes the shape of the palm. Then the shape model of the palm is calculated with principal component analysis. Finally, the color likelihood degree is used to replace the gray information for target fitting. The improved ASM method reduces the complexity, while improves the accuracy and robustness.

에너지 저장기술의 최적 서비스 선정 방법 (Optimal ES (Energy Storage) Service Selection Method)

  • 이지현;제갈성;김현실;맹종호
    • Current Photovoltaic Research
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    • 제11권2호
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    • pp.58-65
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    • 2023
  • The expanding significance of energy storage (ES) technology is increasing the acceptability of power systems by augmenting renewable energy supply. To deploy such ES technologies, we must select the optimal technology that meets the requirements of the system and confirm the technical and economic feasibility of the business model based on it. Herein, we propose a method and tool for selecting the optimal ES technology and service suitable for meeting the requirements of the system, based on its performance characteristics. The method described in this study can be used to discover and apply various ES technologies and develop business models with excellent economic feasibility.

Passaging Method for Expansion of Undifferentiated Human Embryonic Stem Cells by Pipetting Technique

  • Lee, Sung-Geum;Moon, Sung-Hwan;Lee, Soo-Hong;Lee, Hey-Jin;Kim, Jae-Hwan;Chung, Hyung-Min
    • Reproductive and Developmental Biology
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    • 제30권4호
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    • pp.287-291
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    • 2006
  • We have developed a new passaging technique for the expansion of human embryonic stem cells (hESCs) that involves simply pipetting portions of hESCs acquired from colonies, reducing the laborious and time-consuming steps in the expansion of hESCs. Compared to general mechanical methods of passaging, our pipetting method allowed hESCs colonies to be broken into small fragments, which showed significantly higher attachment rates onto feeder cell layers. This technique produced three times the number of hESCs colonies than conventional mechanical methods. In addition, this pipetting method allowed us to distinguish differentiated hESCs from undifferentiated hESCs during hESCs colony pipetting. The hESCs cultured by pipetting method displayed normal human chromosomes for over 60 passages. According to RT-PCR and immunohistochemical analysis, the hESCs successfully maintained their undifferentiated state and pluripotency which was also confirmed by teratoma formation in viva Therefore, the pipetting method described in this study is a useful tool to efficiently and quickly expand hESCs on a large scale without enzyme treatment.