• Smart Structures and Systems
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• v.22 no.1
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• pp.105-120
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• 2018

In this paper, the nonlinear free and forced vibration responses of sandwich nano-beams with three various functionally graded (FG) patterns of reinforced carbon nanotubes (CNTs) face-sheets are investigated. The sandwich nano-beam is resting on nonlinear Visco-elastic foundation and is subjected to thermal and electrical loads. The nonlinear governing equations of motion are derived for an Euler-Bernoulli beam based on Hamilton principle and von Karman nonlinear relation. To analyze nonlinear vibration, Galerkin's decomposition technique is employed to convert the governing partial differential equation (PDE) to a nonlinear ordinary differential equation (ODE). Furthermore, the Multiple Times Scale (MTS) method is employed to find approximate solution for the nonlinear time, frequency and forced responses of the sandwich nano-beam. Comparison between results of this paper and previous published paper shows that our numerical results are in good agreement with literature. In addition, the nonlinear frequency, force response and nonlinear damping time response is carefully studied. The influences of important parameters such as nonlocal parameter, volume fraction of the CNTs, different patterns of CNTs, length scale parameter, Visco-Pasternak foundation parameter, applied voltage, longitudinal magnetic field and temperature change are investigated on the various responses. One can conclude that frequency of FG-AV pattern is greater than other used patterns.

• Ocean Systems Engineering
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• v.6 no.4
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• pp.363-375
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• 2016

Large numbers of submarine pipelines are laid as the world now is attaching great importance to offshore oil exploitation. Free spanning of submarine pipelines may be caused by seabed unevenness, change of topology, artificial supports, etc. By combining Iwan's wake oscillator model with the differential equation which describes the vibration behavior of free-span submarine pipelines, the pipe-fluid coupling equation is developed and solved in order to study the effect of both internal and external fluid on the vibration behavior of free-span submarine pipelines. Through generalized integral transform technique (GITT), the governing equation describing the transverse displacement is transformed into a system of second-order ordinary differential equations (ODEs) in temporal variable, eliminating the spatial variable. The MATHEMATICA built-in function NDSolve is then used to numerically solve the transformed ODE system. The good convergence of the eigenfunction expansions proved that this method is applicable for predicting the dynamic response of free-span pipelines subjected to both internal flow and external current.

• Natural Product Sciences
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• v.25 no.3
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• pp.215-221
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• 2019

Inflammation is the crucial biological process of immune system which acts as body's defense and protective response against the injuries or infection. However, the systemic inflammation devotes the adverse effects such as multiple inflammation associated diseases. One of the best ways to treat this entity is by blocking the tumor necrosis factor alpha ($TNF-{\alpha}$) and TNF-related apoptosis-inducing ligand (TRAIL) to avoid the proinflammation cytokines production. Thus, this study aims to evaluate the potency of Sambucus bioactive compounds as anti-inflammation through in silico approach. In order to assess that, molecular docking was performed to evaluate the interaction properties between the $TNF-{\alpha}$ or TRAIL with the ligands. The 2D structure of ligands were retrieved online via PubChem and the 3D protein modeling was done by using SWISS Model. The prediction results of the study showed that caffeic acid (-6.4 kcal/mol) and homovanillic acid (-6.6 kcal/mol) have the greatest binding affinity against the $TNF-{\alpha}$ and TRAIL respectively. This evidence suggests that caffeic acid and homovanillic acid may potent as anti-inflammatory agent against the inflammation associated diseases. Finally, this study needs further examination and evaluation to validate the potency of Sambucus bioactive compounds.

• Journal of Electrochemical Science and Technology
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• v.10 no.4
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• pp.394-401
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• 2019

The unique study of TiO₂ sol-gel modified carbon paste electrode (CPE) nanocomposites have been developed for electrochemical sensor detecting fipronil pesticide compound. We develop the easy synthesized TiO₂ via a sol-gel method and modified in CPE which applied electrochemical system as cyclic voltammetry (CV) because the concentration is proportional with current peaks. We discover the TiO₂ optimal mass used of 0.1 g which is compared with 0.7 g carbon and 0.3 mL paraffin. It has high-current anodic (Ip_a) of 1.13×10³ μA and high-current cathodic (Ip_c) -0.96×10³ μA in scan rate of 0.5 V/s. The limit of detection (LOD) of fipronil has been determined of 34.0×10^-5 μM in percent recovery of 0.8%. Its high-stability for lifetime TiO₂-CPE nanocomposites was expressed for 13 days which mean that can be used for detecting fipronil pesticide.

• Journal of Korean Society of Steel Construction
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• v.22 no.3
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• pp.241-251
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• 2010

This paper presents the development of a new analytical solution to the governing differential equation for isotropic annular sector plates subjected to uniform loading in a three-dimensional polar coordinate system. The 4th order governing partial differential equation (PDE) was converted to an ordinary differential equation (ODE) by assuming the Levy-type series solution form and the subsequent mathematical operations. Finally, a series-type solution was assembled with homogeneous and nonhomogeneous solution parts after operating real values and complex conjugates derived from the characteristic equation. To demonstrate the convergence rate and the accuracy of the featured method, several examples with various sector angles were selected and solved. The deflections and internal moments in the example annular sector plates that were obtained from the proposed solution were compared with those obtained from other analytical studies and numerical analyses using the finite element analysis package program, ABAQUS. Very good agreement with the results of other analytical and numerical methodologies was shown.

• Broadcasting and Media Magazine
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• v.10 no.1
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• pp.99-112
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• 2005

Christian Metz, the precursor of cine-semiology, considered cinema as a language in the sense that it is a set of messages grounded in a given matter of expression, and a signifying practice characterized by specific codifications. According to Metz, film forms a structured network produced by the interweaving of cinematic codes, within which cinematic subcodes represent specific usages of the particular code. For Metz, cinematic language is a totality of cinematic codes and subcodes, and history of the cinema is the trace of the competition, incorporations and exclusions of the subcodes. He also suggested a filmic text is not just a list of codes in effect, but a process of constant displacement and deformation of codes. Following Metz' textual analysis methodology, I investigated the formal configuration of Hayao Miyazaki‘s animation, Spirited Away. It is interesting to trace the interweaving of cinematic codes in Spirited Away, i.e. codes of lighting, color, movement, and auteurism, across the animation. I focused on the first scene at the bridge to Yubaba's bathhouse, analyzing each cinematic code and its subcode applied. The first bridge scene is carefully constructed to stand out the confrontation of Chihiro (with Haku) and the bathhouse. The bathhouse is not just a building, it represents the powerful witch, Yubaba, yet to appear on the scene, and functions as an antipode to Chihiro. In each shot, every subcode within the codes of framing, direction, angle, color, lighting and movement is used to maximize the contrast between the dominant bathhouse and the feeble 10-year-old girl. In Spirited Away, the subcodes within each cinematic ode are constantly competing and displacing each other to augment the antithesis between the characters and develop the narrative. As Metz's argument that film constitutes a quasi-linguistic practice as a pluricodic medium, Spirited Away communicates with the spectators with the combination and displacement of these cinematic codes and subcodes.

• Economic and Environmental Geology
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• v.34 no.2
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• pp.227-241
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• 2001

Several $Co_2$-rich springs in the Chungcheong area, Le., the Angsung spring, the Chojung spring, the Myungam spring, the Bukang spring and the Daepyung spring have been long known for their particular water chemistry. The occurrences of these springs are closely related to the geologic structure of Mesozoic granite such as dyke swarms, fault zones and the geologic boundary between granite and its adjacent gneiss. The $Co_2$-rich water samples show a high $Co_2$ concentration ($P_{CO2}$ 0.25 atm to 0.99 atm), weak acidic pHs and the electrical conductivity ranging from 101 to 2,950 ${\mu}$S/cm. The $Co_2$-rich water samples are classified into the Ca-$HC0_3$ type and the Ca(Na)-$HCO_3$) type in chemical composition. Environmental isotopic data $^{2}H/^{1}H, ^{18}O/^{16}O$) indicated that $Co_2$-rich water was meteoric origin. The ${\delta}^{13}C$ values of $Co_2$-rich water range from -3.1$\textperthousand$ to -6.8$\textperthousand$ PDB. The values indicate that $H_2CO_3^0$ and $HC0_3^-$ of the water samples are mainly originated from a deep-seated source and partly contributed from carbonatc minerals. The major minerals determining the chemistry of $Co_2$-rich watcr arc probably the carbonate minerals which are present as veins and secondary minerals, and the plagiocalse in granite and gneiss.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.83-88
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• 2008

Purpose: To design an anamorphic aspherical prism lens for the HMD optical system. Methods: First, we get the initial data, needed in design, which are distances between each surface etc., by analyzing user's demended specifications and by drawing geometrically the shape of prism lens by using CAD. Based on these data and using 'ode V' which is an optical design software, we could progress the optimization in which we treat the coefficients of the anamorphic aspherical surface as the principal variables. To reduce the cost in DTM manufacturing, we would optimize the optical system with the transmitting surface, existed in the direction of video device among 3 surfaces of the prism lens, remaining as a plane. Results: we could design one anamorphic aspherical prism lens which has the finite ray aberration of 15 ${\mu}m$, the distortion of 0.5%, and the MTF value of 0.3 over at 36 lp/mm for the video device of 12 mm ${\times}$ 9 mm size. Conclusions: We designed a prism lens used for HMD. This prism lens has the optical capacities of 15 ${\mu}m$ finite ray aberration and 0.5% distortion for the video device of 12 mm ${\times}$ 9 mm size, and become the optical system having the MTF value of 0.3 over at 36 lp/mm.

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

• The Journal of Korean Philosophical History
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• no.59
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• pp.261-286
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• 2018

It is possible to communicate with objects in various styles, but especially the poem[詩], the ode[賦], the inscription[銘] are remarkable. The word is not the mouth, but the mind and the soul. Therefore, if a person is in a relationship with an object that defines the person, what conversation with the object is the person's inner. So if you know what a person has been with things, you can imagine his outer surface, and you can get inner if you know what you talked about. Seo Kyung-duk who lived a poverty life, but can not live without things, so his things are not a thing, Seo Kyung-duk also recorded especially about the dojookjang[bamboo cane], the buchae[fan], and the $k{\breve{o}}mungo$[Korean lute] Seo Kyung-duk with the buchae, Seo Kyung-duk with the dojookjang, and Seo Kyung-duk with the $k{\breve{o}}mungo$. These are the pictures we can imagine. And I can draw Seo Kyung-duk to talk with those things. Seo Kyung-duk, who is reflected in the dojookjang, shows the reality of participating in the rescue of the people's hardships and the stubborn world. Seo Kyung-duk, who is reflected in the buchae, is a philosopher who explores the origin of existence with the appearance of realistic preachers who have to wash away the difficulties of the people. Seo Kyung-duk, who is reflected in the $k{\breve{o}}mungo$, is a philosopher who grasps Ki(氣) the phenomenon and the source, the immaterial and the material, the type and the intangible. Both the strings and non-strings are $k{\breve{o}}mungos$. The $k{\breve{o}}mungo$ is strong in ideology symbolizing the Confucianism ideological ideals, and Seok Kyung-duk is also in the extension line. Seo Gyeong-deok, who has seen through the dojookjang, the buchae, and the $k{\breve{o}}mungo$ has a realistic sense of realizing that he should worry about the pain of the world and fulfill a good world. He is a philosopher who pierces the root of existence and can be governed by the logic of Ki(氣).