• Korean Journal of Materials Research
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• v.24 no.1
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• pp.6-12
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• 2014

In the present work, $WO_3$ and $WO_3-TiO_2$ were prepared by the chemical deposition method. Structural variations, surface state and elemental compositions were investigated for preparation of $WO_3-TiO_2$ sonocatalyst. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and transmission electron microscopy (TEM) were employed for characterization of these new photocatalysts. A rhodamine B (Rh.B) solution under ultrasonic irradiation was used to determine the catalytic activity. Excellent catalytic degradation of an Rh.B solution was observed using the $WO_3-TiO_2$ composites under ultrasonic irradiation. Sonocatalytic degradation is a novel technology of treating wastewater. During the ultrasonic treatment of aqueous solutions sonoluminescence, cavitaties and "hot spot" occurred, leading to the dissociation of water molecules. In case of a $WO_3$ coupled system, a semiconductor coupled with two components has a beneficial role in improving charge separation and enhancing $TiO_2$ response to ultrasonic radiations. In case of the addition of $WO_3$ as new matter, the excited electrons from the $WO_3$ particles are quickly transferred to $TiO_2$ particle, as the conduction band of $WO_3$ is 0.74 eV which is -0.5 eV more than that of $TiO_2$. This transfer of charge should enhance the oxidation of the adsorbed organic substrate. The result shows that the photocatalytic performance of $TiO_2$ nanoparticles was improved by loading $WO_3$.

• Journal of the Korean Electrochemical Society
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• v.8 no.2
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• pp.99-105
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• 2005

In this study, the $PPy/CLO_4$ and PPy/PVS composite electrodes were prepared at various polymerization potential by incorporating electrolyte anions of different anion size during constant potential polymerization. The reulting Polypyrrole surfaces were inspected by SEM, and their electrochemical Properties were investigated with CV and ac impedance method. The results of electrochemical analysis were suggested that anion for $PPy/CLO_4$ electrode and cation fir PPy/PVS electrode were transferred during redox reaction. As constant potential of polymerization was increased, the charge transfer resistance of $PPy/CLO_4$ and PPy/PVS was decreased and the electric double layer capacitances of $PPy/CLO_4$ was higher than that of PPy/PVS. The change of PPy/PVS surface was relatively smaller than that of $PPy/CLO_4$ according to electropolymerization potential.

• (The)Study of the Eastern Classic
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• no.69
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• pp.83-114
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• 2017

The purpose of this article is to analyze the standings of working-level officials belonging to Jongbusi (Court of the Royal Clan) holding the rank of "jeong" and below between the 18th and mid-19th Century. Jongbusi, which was headed by a Grade-3 official, was in charge of the compilation of royal genealogy and supervision of royal relatives. During the late Joseon Period, its officials were composed of its chief, jeong, jubu (Grade-6 official), and jikjang (Grade-7 official). By 1864, it was incorporated into Jongchinbu (Office of the Royal Relatives). Jongbusi nangcheong seonsaengan (Register of Staff Officials at the Court of the Royal Clan), which is preserved at the Jangseogak Archives of the Academy of Korean Studies, lists the officials who served at the office between 1794 and its incorporation into Jongchinbu in 1864. The register also includes the officials' ranks, names, DOBs, family clans, their ranks in the offices they were transferred from, their ranks in the office they were transferred to, etc. Those interested view it as a precious relic that provides valuable information on the officialdom of the dynasty. A majority of the officials who served at Jongbusi were those who passed the higher civil service examination. Many of them at the level of jikjang were those who passed the licentiate examination. Their designation as an official was part of the "muneum" system, which granted official posts to descendants of those who accomplished a distinguished service for the country or served as a high-ranking official. They were those transferred from equal or lower positions in another office. Many of jubu-level officials of Jongbusi were those transferred from honorable and important posts of other offices or local administrative offices. Many of jikjang-level officials of Jongbusi were those who previously served as dosa (assistant officials) at Uigeumbu (Bureau of Crime Investigation) headed by a Grade-1 official. The officials' transfer to an office with a lower position like Jongbusi appears to have been for the provision of placing them in working-level positions rather than letting them remain in positions only carrying an honorary title. As for the transfer of officials of Jongbusi to other offices, many of those with the rank of jeong were transferred to lower positions. Supposedly it was because not many Grade-3 positions were vacant. Many of them were transferred to honorable and important posts. Some of them were also transferred to positions at local government offices, supposedly to avoid an excess of personnel at the central government. Those at the level of jubu or jikjang of Jongbusi were transferred to equal or higher posts in other offices. Particularly, most of those holding the position of jikjang (Grade-7) were transferred to higher posts. The family clan that produced the largest number (10%) of Jongbusi officials was the Jeonju Yi Clan, which produced the largest number of those who passed the higher civil service examination. It was also found that the top 20 family clans produced about half of the entirety of Jongbusi officials. According to the aforesaid Jongbusi nangcheong seonsaengan, about 90% of the cases of promotion of Jongbusi officials occurred after the revision of Seonwon boryak (Royal Genealogy of the Joseon Dynasty). It is speculated that the supervision of royal family members, one of the two leading functions assigned to Jongbusi, was suspended in the late Joseon Period. The relevant function does not appear even in chronicles pertaining to the Joseon Dynasty. The reason being had something to do with the sharp decrease in the number of royal family members during the reign of King Injo (r. 1623-1649). Their number was decreased to the extent that royal ceremonies could not be adequately carried out. Naturally, the meaning of supervising royal family members faded. Witnessing such a sorry state of the royal family, Heungseon Daewongun, King Gojong's father who served as the regent, incorporated Jongbusi into Jongchinbu in an effort to enhance the status and authority of the royal family.

• The Journal of Korea Robotics Society
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• v.3 no.3
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• pp.186-193
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• 2008

We propose a novel real-time obstacle avoidance method for rescue robots. This method, named the ELA(Emergency Level Around), permits the detection of unknown obstacles and avoids collisions while simultaneously steering the mobile robot toward safe position. In the ELA, we consider two sensor modules, PSD(Position Sensitive Detector) infrared sensors taking charge of obstacle detection in short distance and LMS(Laser Measurement System) in long distance respectively. Hence if a robot recognizes an obstacle ahead by PSD infrared sensors first, and judges impossibility to overcome the obstacle based on driving mode decision process, the order of priority is transferred to LMS which collects data of radial distance centered on the robot to avoid the confronted obstacle. After gathering radial information, the ELA algorithm estimates emergency level around a robot and generates a polar histogram based on the emergency level to judge where the optimal free space is. Finally, steering angle is determined to guarantee rotation to randomly direction as well as robot width for safe avoidance. Simulation results from wandering in closed local area which includes various obstacles and different conditions demonstrate the power of the ELA.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.19-27
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• 2012

Although message services in mobile environments provide real-time transfer of various contents such as text, multimedia and location, they can't provide dynamic message services based on analysis of message contents. This paper proposes "message as a service" concept and presents the design methodology for a message platform. The message in this paper is composed of the data part and template part which is in charge of view and functional logic of contents. In addition, two parts of a message are transferred separately. If a terminal device stores message templates, message platform can transfer data part only and thus network traffic can be reduced. Besides an efficient network utilization, we can dynamically update message view and its functional logic by modifying templates.

• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.311-329
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• 1991

Electrochemical behavior of surface active Osmium bipyridine complex adsorbed in a monomolecular layer on tin oxide electrodes by the Langmuir-Blodgett method was studied. Theoretical equation of cyclic voltammetry of electrode reactions for redox species adsorbed as monolayer form was discussed by reversible and quasi-reversible waves. The film was transferred onto the $SnO_2$ electrode surface and then amounts of charge on the electrode were measured in the technique of cyclic voltammetry. The electron transfer mediation of these monolayer with $Fe^{2+}$, TEMPOL and others were studied. And the cyclic voltammetry were simulated by taking into account the interaction parameters. From these values, we found it possible to fit almost all measured cyclic voltammograms with these parameters. The recent works and directions using LB method were introduced with various applicable field.

• Journal of Power Electronics
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• v.7 no.4
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• pp.278-285
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• 2007

Recently, plasma display panels (PDP) have become the most promising candidate in the market for large screen size flat panel displays. PDPs have many merits such as a fast display response time and wide viewing angle. However, there are still concerns about high cost because they require complex driving circuits composed of high power switching devices to generate various voltage waveforms for three operational modes of reset, scan, and sustain. Conventional PDP driving circuits use path switches for voltage separation and a scan switch to offer a scan voltage for reset and scan operations, respectively. In addition, there exist reset switches to initialize PDPs by regulating the wall charge conditions with ramp shaped pulses, which means the necessity of specific power devices for the reset operation. Because power for the plasma discharge accompanied by a large current is transferred to a panel via path switches, high power rating switches are used for path switches. Therefore, this paper proposes a novel low-cost PDP driving scheme achieved by not only eliminating path switches but also merging the function of reset switches into other switches used for sustain or scan operations. The simulated voltage waveforms of the proposed topology and experimental results implemented in a 42-inch panel to demonstrate the validity of using a new gate driver that merges the functions of power switches are presented.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1379-1381
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• 1998

Powder electroluminescent device (PELD) structured conventionally dielectric and phosphor layer, between electrode and their layer fabricated by screen printing splaying or spin coating method. To promote performance of PELDs, we approached the experiments for different structure and thickness variation of PELD. Thickness variation($30{\mu}m{\sim}130{\mu}m$) was taken. To investigate electrical and optical properties of PELDs, EL spectrum, transferred charge density using Sawyer-Tower's circuit brightness was measured. Variation of structure in PELDs was as follows: WK-1 (ITO/BaTiO3/ZnS:Cu/Silver paste), WK-2 (ITO/BaTiO3/ZnS:Cu/BaTiO3/ZnS:Silver paste), WK-3 (ITO/BaTiO3/ZnS:Cu/BaTiO3/Silver paste), WK-4(ITO/BaTiO3+ZnS:Cu/Silver paste) As a result, structure of the highest brightness appeared WK-4 possessed 60 ${\mu}m$ thickness. The brightness was 2719 cd/$m^2$ at 100V, 400Hz.

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.2
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• pp.101-105
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• 2006

Nanoscale floating-gate characteristic of colloidal Au nanoparticles electrostatically assembled on the oxidized surface of Si nanowires have been investigated. The Si nanowire split-gate transistor structure was fabricated by electron beam lithography and subsequent reactive ion etching. Colloidal Au nanoparticles with ${\sim}5$ nm diameters were selectively deposited onto the Si nanowire surface by 2 min electrophoresis. It was found that electric fields applied to the self-aligned split side gates allowed charge to be transferred on the Au nanoparticles. It was observed that the depletion mode cutoff voltage, induced by the self-aligned side gates, was shifted by more than 1 V after Au nanoparticle electrophoresis. This may be due to the semi-one dimensional nature of the narrow Si nanowire transport channel, having much enhanced sensitivity to charges on the surface.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.1
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• pp.28-32
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• 2005

In the Langmuir-Blodgett (LB) technique, a monolayer on the water surface is transferred onto a substrate, which is raised and dipped through the surface. From this, multilayers can be obtained in which constituent molecules are periodically arranged. The LB technique has attracted considerable interest in the fabrication of electrical and electronic devices. Many researchers have investigated the electrical properties of monolayer and multiplayer films. Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendritic macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and ptoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current.