• Title/Summary/Keyword: Reverse calculation

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Development of a 3D earthwork model based on reverse engineering

  • Kim, Sung-Keun
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.641-642
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    • 2015
  • Unlike for other building processes, BIM for earthwork does not need a large variety of 3D model shapes; however, it requires a 3D model that can efficiently reflect the changing features of the ground shape and provide soil type-dependent workload calculation and information on equipment for optimal management. Objects for earthwork have not yet been defined because the current BIM system does not provide them. The BIM technology commonly applied in the manufacturing center uses real-object data obtained through 3D scanning to generate 3D parametric solid models. 3D scanning, which is used when there are no existing 3D models, has the advantage of being able to rapidly generate parametric solid models. In this study, A method to generate 3D models for earthwork operations using reverse engineering is suggested. 3D scanning is used to create a point cloud of a construction site and the point cloud data are used to generate a surface model, which was then converted into a parametric model with 3D objects for earthwork

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Analysis of the Salt Separation and Concentration Using Counter-current Reverse Osmosis Spiral Wound Module (향류식 역삼투 나권형 모듈을 이용한 염분리농축 특성 해석)

  • 조한욱;민병렬;최광호
    • Membrane Journal
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    • v.4 no.3
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    • pp.142-151
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    • 1994
  • Counter-current type reverse osmosis spiral wound module was manufactured for the separation and concentration of salf solution. The ratio of permeate volumetric flow rate vs. brine volumetric flow rate was effective parameter between rejection and degree of cocentration. The reflection coefficient was correspondent to the relation between rejection and degree of cocentration by Spiegler-Kedem model. Counter-current reverse osmosis process had more osmotic pressure drop effect and more degree of concentration than general reverse osmosis process. As a result of computer calculation, the extension of module length than module diameter was more effective for the increase of degree of concentration.

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Purification and Partial Amino Acid Sequence of a Bacteriocin Produced by Lactococcus, sp. HY449 (Lactococcus sp. HY449가 생산한 Bacterisocin의 정제)

  • 오세종;이상준;김경태;김상교;박연희;백영진
    • Microbiology and Biotechnology Letters
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    • v.29 no.3
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    • pp.155-161
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    • 2001
  • A bactriocin produced by Lactrococcus sp. HY449 was purified by sequential purfication steps such as n-propanol-acetone precipitation ion -exchange chromatography using CM-Sequential CL6B. gel filtration chromatography using Sephacry HR100 and reverse-phase chromatography using pro RPC HR 5/10. Reverse-phase chromatography the final step of the purfication yielded a single symmetrical peak of bacteriocin activity The purification resulted in final yield of 3.25% and 413.35 fold increase of the specific activity of bacteriocin. The active fraction from reverse-phase chromatography was used for N-terminal amino acid analysis . The purified bacteriocin contained isoleucine, leucine, methionine, and glycine at but N-terminal end no aromatic amino acids. Calculation of the number of amino acid residues in the bacteriocin revealed that it is consisted of 32 residues assuming the molecular weight of bacteriocin to be about 3.6kDa. Edman degrandation elucidated amino acid residues of the first four of the N-terminus to be $NH_2$-Ile-Leu-Pro-GIn.

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Trapezoidal Cyclic Voltammetry as a Baseline for Determining Reverse Peak Current from Cyclic Voltammograms

  • Carla B. Emiliano;Chrystian de O. Bellin;Mauro C. Lopes
    • Journal of Electrochemical Science and Technology
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    • v.15 no.3
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    • pp.405-413
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    • 2024
  • Several techniques for determining the reverse peak current from a cyclic voltammogram (CV) for a reversible system are described in the literature: CV itself as a baseline with long switching potential (Eλ) that serves as a baseline for other CVs, Nicholson equation that uses CV parameters to calculation reverse peak current and linear extrapolation of the current obtained at the switching potential. All methods either present experimental difficulties or large errors in the peak current determination. The paper demonstrates, both theoretically and experimentally, that trapezoidal cyclic voltammetry (TCV) can be used as a baseline to determine anodic peak current (iap) with high accuracy and with a switching potential shorter than that used by CV, as long as Eλ is at least 130 mV away from the cathodic peak. Beyond this value of switching potential the electroactive specie is completely depleted from the electrode surface. Using TCV with Eλ = 0.34 V and a switching time (tλ) of 240 s as a baseline, the determination of the reverse peak current presents a deviation from the expected value of less than 1% for most of the CVs studied (except cases when Eλ is close to the direct potential peak). This result presents better accuracy than the Nicholson equation and the linear extrapolation of the current measured at the switching potential, in addition to presenting a smaller error than that obtained in the acquisition of the experimental current. Furthermore, determining the reverse peak current by extrapolating the linear fit of iap vs. ${\sqrt[1/]{t_{\lambda}}}$ to infinite time gave a reasonable approximation to the expected value. Experiments with aqueous potassium hexacyanoferrate (II) and ferrocene in acetonitrile confirmed the theoretical predictions.

The Effects of Counting Ability on Young Children's Mathematical Ability and Mathematical Learning Potential (수세기 능력이 유아의 수학능력과 수학학습잠재력에 미치는 영향)

  • Choi, Hye-Jin;Cho, Eun Lae;Kim, Sun Young
    • Korean Journal of Child Studies
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    • v.34 no.1
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    • pp.123-140
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    • 2013
  • The purpose of this study was to examine the effects of counting ability on young children's mathematical ability and mathematical learning potential. The subjects in this study were 75 young children of 4 & 5 years old who attended kindergartens and child care center in the city of B. They were evaluated in terms of counting ability, mathematical ability and mathematical learning potential(training and transfer) and the correlation between sub-factors and their relative influence on the partipants' mathematical ability was then analyzed. The findings of the study were as follows : First, there was a close correlation between the sub-factors of counting and those of mathematical ability. As a result of checking the relative influence of the sub-factors of counting on mathematical ability, reverse counting was revealed to have the largest impact on total mathematical ability scores and each sub-factors including algebra, number and calculation, geometry and measurement. Second, the results revealed a strong correlation between counting ability and mathematical learning ability. Regarding the size of the relative influence of the sub-factors of counting ability on training scores, reverse counting was found to be most influential, followed by continuous counting. While in relation to transfer scores, reverse counting was found to exert the greatest influence.

Evaluation of calcium carbonate scale formation on system design of seawater reverse osmosis plants (해수담수화 시설의 시스템 구성에 따른 $CaCO_3$ 스케일 형성능 진단)

  • Kang, Nam-Wook;Choi, Yang-Hun;Lee, Hye-Ju;Lee, Seock-Heon;Kweon, Ji-Hyang
    • Journal of Korean Society of Water and Wastewater
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    • v.24 no.2
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    • pp.143-155
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    • 2010
  • Fouling by inorganic scales needs to be prevented to effectively operate sea water reverse osmosis(SWRO) membrane systems. The extents of inorganic scaling with different array designs including one-pass, two-pass and several hybrid designs were evaluated using seawater from southern sea near the city of Chang-Won. The used methods for evaluation were Stiff and Davis Index(S&DSI) calculation and several laboratory experiments. The formation potential of inorganic scale fouling was quite great under the examined conditions, which was confirmed by the laboratory experimental results. The inorganic scale was not avoidable fouling if any anti-scaling measures were not applied. The RO showed decreased flux under the scale formation conditions. The increases in S&DSI from 1.43 to 5 made small decreases in flux, which indicated that formation of inorganic scales had more substantial effects on RO flux than amount of inorganic scales.

A Study on Calculation of Composites Lamina Material Properties through Reverse Engineering of Light Weight Composite Car-body (경량 복합재 차체 구조의 역설계를 통한 복합재료 라미나 물성 산출 기법 연구)

  • Moon, Jin Bum;Kim, Jihoon;Jang, Hong Kyu;Park, Jisang
    • Transactions of the Korean Society of Automotive Engineers
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    • v.25 no.1
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    • pp.1-10
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    • 2017
  • In reverse engineering, one of the main tasks is reconstructing the mechanical properties of used materials. For an isotropic material, it could be defined by a single tensile test using a coupon extracted from the structure. In contrast, CFRP composites require many tests and complex procedures to define all the material properties because CFRP is an orthotropic material and a stacked laminate. In this paper, the procedure to reconstruct composite material properties is studied by using the classical lamination theory and the test data of three different laminates from a composite structure. A sample reconstruction of composite material properties using a composite car body is introduced to verify the method.

NUCLIDE SEPARATION MODELING THROUGH REVERSE OSMOSIS MEMBRANES IN RADIOACTIVE LIQUID WASTE

  • LEE, BYUNG-SIK
    • Nuclear Engineering and Technology
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    • v.47 no.7
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    • pp.859-866
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    • 2015
  • The aim of this work is to investigate the transport mechanism of radioactive nuclides through the reverse osmosis (RO) membrane and to estimate its effectiveness for nuclide separation from radioactive liquid waste. An analytical model is developed to simulate the RO separation, and a series of experiments are set up to confirm its estimated separation behavior. The model is based on the extended Nernst-Plank equation, which handles the convective flux, diffusive flux, and electromigration flux under electroneutrality and zero electric current conditions. The distribution coefficient which arises due to ion interactions with the membrane material and the electric potential jump at the membrane interface are included as boundary conditions in solving the equation. A high Peclet approximation is adopted to simplify the calculation, but the effect of concentration polarization is included for a more accurate prediction of separation. Cobalt and cesium are specifically selected for the experiments in order to check the separation mechanism from liquid waste composed of various radioactive nuclides and nonradioactive substances, and the results are compared with the estimated cobalt and cesium rejections of the RO membrane using the model. Experimental and calculated results are shown to be in excellent agreement. The proposed model will be very useful for the prediction of separation behavior of various radioactive nuclides by the RO membrane.

Cost Estimation and Validation based on Natural Language Requirement Specifications

  • So Young Moon;R. Young Chul Kim
    • International Journal of Internet, Broadcasting and Communication
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    • v.15 no.2
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    • pp.218-226
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    • 2023
  • In Korea, we still use function point based cost estimations for software size and cost of a project. The current problem is that we make difficultly calculating function points with requirements and also have less accurate. That is, it is difficult for non-experts to analyze requirements and calculate function point values with them, and even experts often derive different function points. In addition, all stakeholders strongly make the validity and accuracy of the function point values of the project before /after the development is completed. There are methods for performing function point analysis using source code [1][2][3][4] and some researchers [5][6][7] attempt empirical verification of function points about the estimated cost. There is no research on automatic cost validation with source code after the final development is completed. In this paper, we propose automatically how to calculate Function Points based on natural language requirements before development and prove FP calculation based on the final source code after development. We expect validation by comparing the function scores calculated by forward engineering and reverse engineering methods.

A Numerical Study on the Automotive Torque Converter(Part I) - Hydraulic Design and Evaluation of Circulation Flow Rate - (자동차용 토크 컨버터의 수치해석적 연구(Part I) - 수력학적 설계와 순환유량의 평가 -)

  • 김홍식;박재인;주원구;조강래
    • Transactions of the Korean Society of Automotive Engineers
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    • v.6 no.5
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    • pp.28-36
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    • 1998
  • In order to establish the hydraulic design process of the torque converter, pump, turbine and stator were designed by reverse design method including one dimensional analysis, angular momentum distribution and forced vortex design. And the significance of evaluation of the circulation flow rate in torus of the torque converter was verified by numerical calculation if the combined blade rows of pump and turbine. It was confirmed that the computational method using interrow mixing model by Park and Cho was reliable to predict the flow-field and performance of the torque converter.

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