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The Mobile Shopping System using MVLS (MVLS를 이용한 모바일 쇼핑 시스템)

  • Kim, Young-Jong
    • Journal of Korea Society of Industrial Information Systems
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    • v.15 no.5
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    • pp.119-124
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    • 2010
  • In this paper planed mobile shopping system using MVLS. MVLS is based on braille system, and list this to a square color box. This is can accomplish convenience of use and encipherment of fundamental personal information. Also, this system has advantage to fast communication speed because that has little size packets. Planed system does and fit this in shopping to graft together mobile-phone, smart-phone and tablet-pc that the such MVLS and most of internal adult are possessing. User can more fast finish shopping just photographing and press the button that show on TV or PC monitor and printed materials etc. by camera of mobile phone.

Influence of oil pipe corrosion defects on the sealing performance of annular BOP

  • Dong, Liangliang;Tang, Yuan;Wang, Liuyang
    • Structural Engineering and Mechanics
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    • v.84 no.3
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    • pp.337-344
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    • 2022
  • Due to corrosion defects on the surface of the oil pipe, the sealing performance of the annular blowout preventer (BOP) decreases, and the leakage of toxic and harmful gases such as H2S and SO2 will threaten the safety of operators on the well. Therefore, this paper establishes the FE model for evaluating the sealing performance of BOP-oil pipe corrosion defects, which is based on the rubber large deformation theory and rubber core sealing mechanism, and designs the experiment of BOP sealing performance to verify the accuracy of the FE model. The sealing performance of BOP sealing oil pipe with corrosion defects is studied. The research results show that the sealing performance of BOP is more sensitive to the axial size of corrosion defects. With the increase of oil pipe outer diameter, the critical size of defects increases continuously. The sensitivity of radial and depth dimensions is low, When for 88.9 mm outer diameter oil pipe, the axial critical size of corrosion defect is 20 mm, the radial critical size is 16 mm and the critical depth is 2 mm. Fit the formula between the outer diameter of oil pipe and the piston increment. According to the formula, the operator can calculate the piston stroke increment required by the BOP to complete the sealing when the oil pipe is corroded.

Measurement of K0 and K'0 during loading and unloading of loose sand

  • Shay Nachum;Mark Talesnick;Sam Frydman
    • Geomechanics and Engineering
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    • v.32 no.1
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    • pp.97-110
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    • 2023
  • The coefficient of lateral earth pressure at rest in loose sand during virgin loading, K0 , and during unloading, K'0 , have been determined from laterally confined load-unload tests. The tests included measurement of lateral pressure with null pressure gauges, side wall friction with newly designed friction meters and applied pressure and base pressure with load cells. The importance of accounting for side-wall friction when evaluating the distribution of vertical pressure over the height of the soil specimen was demonstrated. Relatively uniform friction was observed during loading, but this was not the case during unloading unless friction reduction measures were employed. While the measured value of K0 was found to be close to, if slightly higher than the value commonly estimated on the basis of friction angle, φ', the ratio of K'0 to K0 was found to reasonably fit an expression of the form K'0/K0 = 1 + C·log(OCR), with C equal to 1 in the present tests.

Pre-ozonation for removal of algal organic matters (AOMs) and their disinfection by-products (DBPs) formation potential

  • Jing Wang;Se-Hyun Oh;Yunchul Cho
    • Membrane and Water Treatment
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    • v.14 no.2
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    • pp.77-83
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    • 2023
  • As a result of algal bloom, algal organic matters (AOMs) are rapidly increased in surface water. AOMs can act as precursors for the formation of harmful disinfection by-products (DBPs), which are serious problems in water treatment and human health. The main aim of this study is to characterize the formation of DBPs from AOMs produced by three different algae such as Oscillatoria sp., Anabaena sp., and Microcystis aeruginosa under different algal growth phases. In an effort to examine formation of DBPs during chlorination, chloroform (TCM), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were determined under various CT (product of disinfectant concentration and contact time, mg·min/L) values. Generally, the amounts of DBPs tended to increase with increasing CT values at the most growth phases. However, there was a significant difference between the amounts of DBPs produced by the three algal species at different growth phases. This result is likely due to the chemical composition variability of AOM from different algae at different growth phases. In addition, the effect of pre-ozonation on coagulation for the removal of AOMs from three algal species was investigated. The pre-ozonation had a positive effect on the coagulation/flocculation of AOMs.

Numerical investigation of the hysteretic response analysis and damage assessment of RC column

  • Abdelmounaim Mechaala;Benazouz Chikh;Hakim Bechtoula;Mohand Ould Ouali;Aghiles Nekmouche
    • Advances in Computational Design
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    • v.8 no.2
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    • pp.97-112
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    • 2023
  • The Finite Element (FE) modeling of Reinforced Concrete (RC) under seismic loading has a sensitive impact in terms of getting good contribution compared to experimental results. Several idealized model types for simulating the nonlinear response have been developed based on the plasticity distribution alone the model. The Continuum Models are the most used category of modeling, to understand the seismic behavior of structural elements in terms of their components, cracking patterns, hysteretic response, and failure mechanisms. However, the material modeling, contact and nonlinear analysis strategy are highly complex due to the joint operation of concrete and steel. This paper presents a numerical simulation of a chosen RC column under monotonic and cyclic loading using the FE Abaqus, to assessthe hysteretic response and failure mechanisms in the RC columns, where the perfect bonding option is used for the contact between concrete and steel. While results of the numerical study under cyclic loading compared to experimental tests might be unsuccessful due to the lack of bond-slip modeling. The monotonic loading shows a good estimation of the envelope response and deformation components. In addition, this work further demonstrates the advantage and efficiency of the damage distributions since the obtained damage distributions fit the expected results.

Comparative study of Pb (II) adsorption from water on used cardboard and powdered activated carbon

  • Benhafsa, Fouad. Mekhalef;Bouchama, Abdelghani.;Chadli, Aicha.;Tadjer, Belgacem.;Addad, Djelloul.
    • Membrane and Water Treatment
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    • v.13 no.2
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    • pp.73-83
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    • 2022
  • In the present study, we compared the adsorption capacity of Pb (II) from contaminated water of used cardboard (UC) and a commercial powdered activated carbon (PAC), the latter has been characterized by different techniques, namely X-ray diffraction (XRD), scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), wavelength dispersion x-ray fluorescence (WDXRF), infrared spectroscopy (IR) and surface area B.E.T analyzer. The effect of various parameters, such as the pH, the contact time, the amount of adsorbent, and the temperature on the adsorption of Pb (II) on both materials was investigated. The Pb (II) adsorptions are perfectly described by a pseudo-second-order model, while the intraparticle diffusion is a decisive step after the first minutes of contact. The fit to the Langmuir and Redlich-Peterson models seems perfect for these adsorption reactions. (PAC) showed a greater affinity for Pb (II) compared to (UC) and the adsorption of Pb (II) ions is strongly pH-dependent, on the other hand, the increase in temperature doesn't have much influence on the two solids. This study showed that the capacity of (UC) to adsorb Pb (II) from an aqueous solution is greater than two-thirds of that of (PAC).

Dynamic shear modulus and damping ratio of saturated soft clay under the seismic loading

  • Zhen-Dong Cui;Long-Ji Zhang;Zhi-Xiang Zhan
    • Geomechanics and Engineering
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    • v.32 no.4
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    • pp.411-426
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    • 2023
  • Soft clay is widely distributed in the southeast coastal areas of China. Many large underground structures, such as subway stations and underground pipe corridors, are shallow buried in the soft clay foundation, so the dynamic characteristics of the soft clay must be considered to the seismic design of underground structures. In this paper, the dynamic characteristics of saturated soft clay in Shanghai under the bidirectional excitation for earthquake loading are studied by dynamic triaxial tests, comparing the backbone curve and hysteretic curve of the saturated soft clay under different confining pressures with those under different vibration frequencies. Considering the coupling effects of the confining pressure and the vibration frequency, a fitting model of the maximum dynamic shear modulus was proposed by the multiple linear regression method. The M-D model was used to fit the variations of the dynamic shear modulus ratio with the shear strain. Based on the Chen model and the Park model, the effects of the consolidation confining pressure and the vibration frequency on the damping ratio were studied. The results can provide a reference to the earthquake prevention and disaster reduction in soft clay area.

Semi-Rigid connections in steel structures: State-of-the-Art report on modelling, analysis and design

  • Celik, Huseyin Kursat;Sakar, Gokhan
    • Steel and Composite Structures
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    • v.45 no.1
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    • pp.1-21
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    • 2022
  • In the structural analysis of steel frames, joints are generally considered as rigid or hinged considering their moment transfer ability. However, the first studies conducted with the beginning of the 20th century showed that the joints do not actually fit these two definitions. In reality, a joint behaves between these two extreme points and is called semi-rigid. Including the actual state of the joint in the structural analysis provides significant economic advantages, so the subject is an intense field of study today. However, it does not find enough application area in practice. For this reason, a large-scale literature published from the first studies on the subject to the present has been examined within the scope of the study. Three important points have been identified in order to examine a joint realistically; modelling the load-displacement relationship, performing the structural analysis and how to design. Joint modelling methods were grouped under 7 main headings as analytical, empirical, mechanical, numerical, informational, hybrid and experimental. In addition to the moment-rotation, other important external load effects like axial force, shear and torsion were considered. Various evaluations were made to expand the practical application area of semi-rigid connections by examining analysis methods and design approaches. Dynamic behaviour was also included in the study, and besides column-beam connections, other important connection types such as beam-beam, column-beam-cross, base connection were also examined in this paper.

An Empirical Study on the Factors Affecting the Intention to Use M2E Services

  • Sang Hoon Lee;Min-Ju Kim;Su-Yeon Kim
    • Asia pacific journal of information systems
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    • v.33 no.3
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    • pp.792-811
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    • 2023
  • Recently, Web 3.0 services such as virtual currency, block chain, and NFT are attracting public attention. Users who depended on platforms are moving away from being dependent on service providers and moving to Web 3.0 services. Representative services of Web 3.0 include P2E (Play to Earn) and M2E (Move to Earn). In the case of P2E, various studies have been conducted as it is widely covered in the press and media, but research on M2E is relatively lacking. This study attempts to identify the intention to use M2E by using the expanded technology acceptance model. External factors were selected based on M2E's own characteristics and personal characteristics, a research model was designed, and the proposed hypotheses were verified through factor analysis and goodness of model fit. As a result of the study, it was confirmed that profitability, innovativeness, and self-expression had a positive effect on perceived characteristics, and that perceived usefulness, perceived enjoyment, and social influence had a positive effect on intention to use. Through the research results, practical implications for efficient service operation that meets the needs of users are presented to M2E platform providers.

Probabilistic analysis of gust factors and turbulence intensities of measured tropical cyclones

  • Tianyou Tao;Zao Jin;Hao Wang
    • Wind and Structures
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    • v.38 no.4
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    • pp.309-323
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    • 2024
  • The gust factor and turbulence intensity are two crucial parameters that characterize the properties of turbulence. In tropical cyclones (TCs), these parameters exhibit significant variability, yet there is a lack of established formulas to account for their probabilistic characteristics with consideration of their inherent connection. On this condition, a probabilistic analysis of gust factors and turbulence intensities of TCs is conducted based on fourteen sets of wind data collected at the Sutong Cable-stayed Bridge site. Initially, the turbulence intensities and gust factors of recorded data are computed, followed by an analysis of their probability densities across different ranges categorized by mean wind speed. The Gaussian, lognormal, and generalized extreme value (GEV) distributions are employed to fit the measured probability densities, with subsequent evaluation of their effectiveness. The Gumbel distribution, which is a specific instance of the GEV distribution, has been identified as an optimal choice for probabilistic characterizations of turbulence intensity and gust factor in TCs. The corresponding empirical models are then established through curve fitting. By utilizing the Gumbel distribution as a template, the nexus between the probability density functions of turbulence intensity and gust factor is built, leading to the development of a generalized probabilistic model that statistically describe turbulence intensity and gust factor in TCs. Finally, these empirical models are validated using measured data and compared with suggestions recommended by specifications.