• Korean Journal of Materials Research
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• v.20 no.7
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• pp.370-373
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• 2010

In fabricating plasma display panels, the photolithographic process is used to form patterns of barrier ribs with high accuracy and high aspect ratio. It is important in the photolithographic process to control the refractive index of the photosensitive paste. The composition of this paste for photolithography is based on the $B_2O_3-SiO_2-Al_2O_3$ glass system, including additives of alkali oxides and rare earth oxides. In this work, we investigated the density, structure and refractive index of glasses based on the $B_2O_3-SiO_2-Al_2O_3$ system with the addition of $Li_2O$, $K_2O$, $Na_2O$, CaO, SrO, and MgO. The refractive index of the glasses containing K2O, Na2O and CaO was similar to that of the [BO3] fraction while that of the SrO, MgO and Li2O containing glasses were not correlated with the coordination fraction. The coordination number of the boron atoms was measured by MAS NMR. The refractive index increased with a decrease of molar volume due to the increase in the number of non-bridging oxygen atoms and the polarizability. The lowest refractive index (1.485) in this study was that of the $B_2O_3-SiO_2-Al_2O_3-K_2O$ glass system due to the larger ionic radius of $K^+$. Based on our results, it has been determined that the refractive index of the $B_2O_3-SiO_2-Al_2O_3$ system should be controlled by the addition of alkali oxides and alkali earth oxides for proper formation of the photosensitive paste.

• The Journal of the Petrological Society of Korea
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• v.10 no.3
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• pp.233-245
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• 2001

With the advent of super-conducting magnet, NMR spectroscopy becomes a very important tool in geology as well as in chemistry. $^{29}Si$ and $^{27}Al$ which are the main components of minerals and contain structural informations, are useful major targets for the NMR study in geology, but some other elements including alkali cations such as $^{23}Na$ are also one of them. NMR can be applied to many different fields. For example, it can be applied to study smaller range of structure (in molecular level) than XRD and TEM. NMR provides us with structural informations such as order-disorder in Al and Si distribution, oxygen coordination number, and distribution of other cations. Another important information that we can obtain from NMR is not only the static structural informations, but also the molecular dynamics. This dynamic informations of molecules also enable us to figure out the frequency of molecular motion and activation energy. Structure of amorphous minerals and chemistry and structure of natural organic materials are also studied by NMR.

• Journal of the Korean housing association
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• v.27 no.4
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• pp.13-22
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• 2016

The long term plan for apartment housing has a important role to make a decision making whether a repair work should be done or not. But, items for repair works are so various that field workers could not understand the context or plan the repair cost and time. These difficulties are drawn from the number of repair items, duplicated application and meaning, new material application and technology time-gap. Therefore, it needs to change or coordinate the repair items to improve the repair condition, reflecting the current material level or repair technologies. In this paper, it aimed at coordination of the repair items through the repair recording sheet which was surveyed in 22 metropolitan areas of Seoul, conducted between 2011 and 2014. The surveyed data are classified into six categories such as building exterior, building interior and so on, according to long term repair plan and the number of data are 1,918. It analyzed the appearing word for repair-concerned and compared the existing items of the long term plan. Items of building exterior are proposed as roof, exterior wall and painting. Building interior has a little meaning to propose the repair items. The water supply facilities are proper to keep the existing repair items. Items of the outdoor facilities could not need a sign board, drainage root and PVC sheath. Through this study, we can coordinate the repair items in apartment and provide the repair item and cost level.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.228-232
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• 2008

In recent years, wireless ad hoc networks have become increasingly popular in both military and civilian applications due to their capability of building networks without the need for a pre-existing infrastructure. Recently, IEEE 802.11 Task Group e has been working on a new mechanism, the Enhanced Distributed Coordination Function (EDCF), to enhance the performance of 802.11 DCF. However, EDCF only reduces the internal collisions within a station, and external collisions between stations remain high in ad-hoc networks. In this paper, we propose to adopt an adaptive backoff window control technique, based on a dynamic value of the initial value of the range in which the backoff is chosen, so the backoff timer is randomly chosen in the range (InitRng, CW-1). We use ns-2 simulation to evaluate the throughput of our scheme. Results show that the throughput is improved for our scheme compared to the original DCF due to the reduced the number of collisions.

• Korean Journal of Social Welfare
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• v.46
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• pp.404-426
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• 2001

The purposes of study were to analyze the characteristics of case management network for the homebound elderly in Puchon and to identify major factors that affect the number of network member. The population of this study was social workers who provide services to the elderly. The results show that license of social work and information closeness have a significant effect on the number of network member among the independent variables. This finding is important for case management in the network. As observed in relationship characteristics, the community welfare center established by the university and city government roles in promoting service coordination.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.301-307
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• 2005

The roots of the plant Korean ginseng have been extensively used in the traditional Chinese herbal medicine. We investigated the standardized extract of Korean ginseng on animal models of anxiety based on exploratory behavior. Korean ginseng extract (KGE) (3, 10 and 30 mg/kg) was administered intra-peritoneally. The anxiolytic activity was studied using elevated plus maze (EPM) paradigm, light/dark apparatus (LDA), open field apparatus (OFA) and the hole board apparatus (HBA). Diazepam (1mg/kg) was used as a standard anxiolytic drug. In EPM, KGE (10 mg/kg) significantly (P < 0.05) increased the time spent in open arms and the number of entries in open arms. In LDA, KGE (10 mg/kg) increased the number of transitions. In OFA, KGE (3 and 10 mg/kg) significantly increased (P < 0.05) the number of squares traversed. In HBA the number of head pokes were significantly increased with KGE (3 and 10 mg/kg). KGE at all selected doses did not affect the motor coordination. Thus, the study suggests that saponin containing standardized Korean ginseng extract possess anxiolytic activity.

• Progress in Superconductivity and Cryogenics
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• v.21 no.4
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• pp.1-5
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• 2019

We investigated the effect of Fe₃O₄ addition on the critical temperature of (Bi, Pb)-2223 polycrystalline samples. Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O_10+δ + x wt. % Fe₃O₄ (x = 0.0, 0.2, 0.4, 0.6, and 0.8) samples were prepared by using a solid-state reaction method. The analysis of X-ray diffraction data indicates that as Fe₃O₄ is added, dominant phase of the sample changes from Bi-2223 to Bi-2212 with an increasing Bi-2201 phase. The transition temperature of the samples drastically decreased with the Fe₃O₄ addition. The resistance data of samples with x = 0.2 and 0.4 showed a double transition indicating a coexistence of Bi-2223 and Bi-2212 phase while the samples with x = 0.6 and 0.8 showed a single transition with a semiconducting behavior. This phase transition may originate from changes in local structure of the Bi-2223 system by Fe₃O₄ addition. Analysis of the pair distribution function of the Cu-O pair in the CuO₂ plane calculated from extended X-ray absorption fine structure data revealed that the oxygen coordination of copper ion changes from CuO₄ planar type (x = 0.0 - 0.4) to CuO₅ pyramidal type (x = 0.6, 0.8). The correlated Debye-Waller factor, providing information on the atomic disorder within the CuO₂ plane, shows an inverse relation to the coordination number. These results indicate that addition of Fe₃O₄ changes the oxygen distribution around Cu in the CuO₂ plane, causing a phase transition from Bi-2223 to more stable Bi-2212/Bi-2201 phases.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.9-19
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• 2016

Since continuous expand in governmental R&D investments and growth number of research institutions, model of multi-agency program has been planned and pushed ahead to settle the inefficiency of investment by the scattered and competitive R&D Programs. However, it was often pointed out that new model's effect has been fall because the institutional inertia of cooperative system between agencies. In this study, we analyze the current state of multi-agency program and suggest the optimal R&D governance model to improve a better direction. Afterward, several problems were turned up and that allocation and execution of the R&D budget separately, less coordination and cooperation among agencies, and absence of typical evaluation system of multi-agency program. Therefore, we suggest some of improvements by analyzing each steps.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1283-1288
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• 2010

A novel polyaminopolycarboxylate ligand with many coordination sites, N,N,$N^1,N^1,N^2,N^2$-[( 2,4,6-tri(aminomethyl)-pyridine]hexakis(acetic acid) (TPHA), was designed and synthesized and its lanthanide complexes $Na_6Tb_2$(TPHA)$Cl_6{\cdot}14H_2O$, $Na_6Eu_2$(TPHA)$Cl_6{\cdot}8H_2O$, $Na_6Gd_2$(TPHA)$Cl_6{\cdot}11H_2O$ and $Na_6Sm_2$(TPHA)$Cl_6{\cdot}9H_2O$ were successfully prepared. The ligand and the complexes were characterized by elemental analysis, IR, mass, NMR and TG-DTA. The TG-DTA studies indicated that the complexes had a high thermal stability, whose initial decomposition temperature was over $270^{\circ}C$. The luminescence properties of the complexes in solid state were investigated and the results suggested that $Tb^{3+}$ and $Eu^{3+}$ ions could be sensitized efficiently by the ligand, especially the Tb(III) complex displayed a very strong luminescence intensity (> 10000) and only displayed characteristic metal-centered luminescence. Also, the correlative comparison between the structure of ligand and luminescence properties showed how the number of the coordination atoms of ligand can be a prominent factor in the effectiveness of ligand-to-metal energy transfer.

• Journal of Fashion Business
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• v.11 no.4
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• pp.69-81
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• 2007

This study, for the purpose of comparing and analyzing 23ea of national unisex apparel brands website consists of product, price, promotion and place divided by marketin gmix. Based of theoretical study and pre-research about the marketing mix, we made the classification standard for the marketing mix and analyzed the unisex apparel brand website according to 4P's individual item and the result was appeared like this. First of all, in the product section, this study provide information about product introduction/guidance, a product figure for item, introduction for new items, propose for coordination and brand introduction/information. Secondly, in the price part, almost apparel brands are provide their product's image, or present their goods photo with price, or displayed through the banner advertisement of discount or special price. Thirdly, For the marketing promotion part, compare to the other component in the most of apparel brand's website, marketing promotion has more section than the other marketing mix. And, especially, various events and customer service space has more weight than the others. Forth, in the place section, it's focused on the information of shopping mall location, contact number, address, and on-line shopping mall. In Conclusion, when the most of apparel brands are doing internet marketing, they're concern to product and promotion, but price and place needs more supplement in the unisex apparel brand's marketing mix.