• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.460-467
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• 2006

Adsorption experiments for $H_2$, $CO_2$, CO, and their binary mixtures on zeolite 5A were performed by static volumetric method. Experimental data were obtained at temperatures of 293.15, 303.15 and 313.15 K and at pressures to 25 atm. The parameters obtained from single component adsorption isotherm. Multicomponent adsorption equilibria could be predicted and compared with experimental data. Langmuir isotherm, Langmuir-Freundlich isotherm and Dual-Site Langmuir isotherm be used to predict the experimental results for binary adsorption equilibria of $CO_2/CO$ and $H_2/CO_2$ on zeolite 5A. Dual-Site Langmuir isotherm showed the best agreement with the experimental results.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.3
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• pp.103-118
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• 2004

Much investment has been to improve quality of web service as internet service is in pursuit of equilibrium. Web site of electronic library which offers various information has to be set a new standard for improving users service satisfaction by developing objsctive evaluation system. In this research we acquired standard of evaluation parameter such as contents, design, navigation, feedback, reference, privacy by analyzing domestic web site of electronic library We evaluated constructed model of usability evaluation using AHP(Analytic Hierarchy Process). We develop 'digital library web site evaluation model' based systematic analysis through polling category selected as evaluation guide.

• Journal of the Korea Institute of Building Construction
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• v.2 no.1
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• pp.147-154
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• 2002

In the Past, The selection of individual method of construction was done by head of construction site or an experienced person very frequently. By doing this, The wrong selection of construction method without exact adjudication of construction site situation lead to increasing of cost and extension of construction term. Finally it will effect all over the construction process. Especially, In case of underground construction in the beginning, there are a lot of a variable factor and it also effect on the entire construction process and it need very careful process. The purpose of this study is to present the best suitable methodology for selection of construction method by considering potential risk of construction method and variables together with external condition for underground construction. The purpose of this study Is to select the most suitable construction method by analysing potential conditions(construction site situation and client request in designing ) To do this, We prepared arrangement rule to arrange the conditions for construction method. And thin make checklist of the analyzing construction method. Though above process, To expect the risk of individual construction method using above risk checklist and using Analytic Hierarchy process among Multiple-Criteria Decision making, the professional opinions is to be adapted. By doing this, it can lead and select the most suitable construction method considering the data which get from risk density test.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.99-117
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• 2001

In the past, The selection of individual method of construction was done by head of construction site or an experienced person very frequently. By doing this, The wrong selection of construction method without exact adjudication of construction site situation lead to increasing of cost and extension of construction term. Finally it will effect all over the construction process. Especially, In case of Underground construction in the beginning, there are a lot of a variable factor and it also effect on the entire construction process and it need rely careful process. The purpose of this study is to present the best suitable methodology fer selection of construction method by considering potential risk of construction method and variables together with external condition for Underground construction. The purpose of this study is to select the most suitable construction method by analysing potential conditions(Construction site situation and Client. Request in designing) To do this, We prepared arrangement rule to arrangement conditions for construction method. And then make Checklist the analyzing construction method. Though above process, To expect the risk of individual construction method using above risk checklist and using Analytic Hierarchy Process among Multiple-Criteria Decision Making, the professional opinions is to be adapted. By doing this, It can lead and select the most suitable considering method considering the data which get from risk density test.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.269-272
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• 2004

The target of this paper is the development of Web-based monitoring & control system which is for effective and economic management of mold manufacturing process. This system has three module; G-code Control, Monitoring Module and Result analysis module. Also, as the environment of development is based on internet, this system which is possible to the remote site management of manufacturing process works on Web. To be possible to control the manufacturing monitoring by client, each module is made ActiveX control and is based on socket communication. This system makes the foundation which is possible to manage the mold manufacturing process efficiently from remote site by matching real-time monitoring with manufacturing process in factory using G-code control and displaying the result of manufacturing using Ch-CGI.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.187-194
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• 2011

Optimizing truck dispatching-intervals is imperative in ready mixed concrete (RMC) delivery process. Intervals shorter than optimal may induce queuing of idle trucks at a construction site, resulting in a long delivery cycle time. On the other hand, intervals longer than optimal can trigger work discontinuity due to a lack of available trucks where required. Therefore, the RMC delivery process should be systematically scheduled in order to minimize the occurrence of waiting trucks as well as guarantee work continuity. However, it is challenging to find optimal intervals, particularly in urban areas, due to variations in both traffic conditions and concrete placement rates at the site. Truck dispatching intervals are usually determined based on the concrete plant managers' intuitive judgments, without sufficient and reliable information regarding traffic and site conditions. Accordingly, the RMC delivery process often experiences inefficiency and/or work discontinuity. Automatic data collection (ADC) techniques (e.g., RFID or GPS) can be effective tools to assist plant managers in finding optimal dispatching intervals, thereby enhancing delivery performance. However, quantitative evidence of the extent of performance improvement has rarely been reported to data, and this is a central reason for a general reluctance within the industry to embrace these techniques, despite their potential benefits. To address this issue, this research reports on the development of a discrete event simulation model and its application to a large-scale building project in Abu Dhabi. The simulation results indicate that ADC techniques can reduce the truck idle time at site by 57% and also enhance the pouring continuity in the RMC delivery process.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.17-17
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• 2011

As a method of countermeasure to bed degradation and armoring phenomena of bed material in the downstream area of dam reservoirs, sediment augmentation (replenished sediment) has been carried out in many Japanese rivers. In general, bed of the replenished sediment site is composed of rocks, because the site is located in the downstream area of the dams and sediment supply is very small. Bed deformation process has been researched by many researchers. As a method of countermeasure to bed degradation and armoring phenomena of bed material in the downstream area of dam reservoirs, sediment augmentation (replenished sediment) has been carried out in many Japanese rivers. In general, bed of the replenished sediment site is composed of rocks, because the site is located in the downstream area of the dams and sediment supply is very small. Bed deformation process has been researched by many researchers. However, most of them can treat movable bed only and cannot be applied to the bed deformation process of sediment on rocks. If the friction angle between the sediment and the bed surface is assumed to be the same as the friction angle between the sediment and the sediment, sediment transport rate must be smaller without sediment deposition layer on the rocks. As a result, the reproduced bed geometry is affected very well. In this study, non-equilibrium transport process of non-cohesive sediment on rigid bed is introduced into the horizontal two dimensional bed deformation model and the model is applied to the erosion process of replenished sediment on rock in the Nakagawa, Japan. Here, the Japanese largest scale sediment augmentation has been performed in the Nakagawa. The results show that the amounts of the eroded sediment and the remained sediment reproduced by the developed numerical model are $56300m^3$ and $26800m^3$, respectively. On the other hand, the amounts of the eroded sediment and the remained sediment measured in the field after the floods are $56600m^3$ and $26500m^3$, respectively. The difference between the model and field data is very small. Furthermore, the bed geometry of the replenished sediment after the floods reproduced by the developed model has a good agreement with the measured bed geometry after the floods. These results indicate that the developed model is able to simulate the erosion process of replenished sediment on rocks very well. Furthermore, the erosion speed of the replenished sediment during the decreasing process of the water discharge is faster than that during the increasing process of the water discharge. The replenished sediment is eroded well, when the top of the replenished sediment is covered by the water. In general, water surface level is kept to be high during the decreasing process of the discharge during floods, because water surface level at the downstream end is high. Hence, it is considered that the high water surface level during the decreasing process of the water discharge affects on the fast erosion of the replenished sediment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.217-220
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• 1995

By substituting Cd$\^$2+/ into both A-site and B-site in PNN-PZ-PT ternary perovskite material, it is possible to determine the effects of the substitution site of Cd$\^$2+/ on sintering behavior. Sintering was performed in the temperature range from 1000$^{\circ}C$ to 1300$^{\circ}C$. The substitution site of Cd$\^$2+/ is identified by XPS spectra. Although Cd$\^$2+/ is substituted into both A-site and B-site in PNN-PZ-PT, Cd$\^$2+/ prefers A-site to B-site. The density is influenced by substitution site of Cd$\^$2+/. If Cd$\^$2+/ replaces Pv$\^$2+/, weight gain is observed during sinterig process. On the contrary, if Cd$\^$2+/ replaces Ni$\^$2+/, weight loss is promoted during sintering. From these weight changes, it is believed that Cd$\^$2+/ changes the bonding strength between B-site cation and oxygen of octahedron in perovskite structure. The changes of lattice parameters as a function of Cd$\^$2+/ content were consistent with those of the bonding strength. The densities of A-site-doped compositions were higher than those of B-site-doped composition.

• KIEAE Journal
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• v.12 no.6
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• pp.77-84
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• 2012

The current architectural design of unit modular has been based on 2D of CAD program, so unit modular character which needs unit information management, as a dried-member system, has no effect on design process. The purpose of this study is We have developed a suitable BIM design process, according to various works of construction, then tried to contribute to supply and activation of the urban-life-housing based on unit modular. The BIM modeling process based on unit modular has been in order of unit combination with preparing manual classification, and, it has been constructed, at construction site, from housing foundation to roof finish by Bottom-up method. At a manufacturing factory, it has been produced in order of 1) grouping materials and parts, 2) fabricating unit boxes, and 3) interference examination of unit boxes, and each order has been classified as housing structure, architecture, plumbing process separately. At a construction site, the fabrication has been done in order of, like as a real housing construction scenario, 1) RC foundation work 2) unit module job-site-fabrication work, 3) roof truss work, 4) plumbing and HVAC work, and 5) housing interior finish work. After modeling process, the interference examination on each work of construction has finally completed modeling. The Unit modular utilizing BIM modeling can make easy housing maintenance through systematic control with preparing manual of unit module information, and securing accurate and speedy construction information. And it will promote design credibility and create maximum effect of unit modular construction method, such as construction period reduction and upgrade of construction quality, etc., through the computer simulation as real as construction environment in cyber space, and with the interfering examination.

• Journal of Conservation Science
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• v.10 no.1 s.13
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• pp.31-37
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• 2001

The metallurgical investigation of four lumps of bronze from the third building site of the northern workshop site at the Neungsan-ri temple site in Buyeo was performed. The microstructures of a section of sample was observed by SEM and qualitative and quantitative analysis of the sample was performed by EDS. The results are as follows: Sample 1 of the lump of bronze from northern workshop site in the third building site at Neungsan-ri temple site and sample 2 are speculated to be low-quality bronze resulting from refinery of matte which formed on the process of bronze refinery. Sample 3 is speculated as a lump of bronze which is one of Cu-Sn system and the one made by alloy only with pure bronze and tin on the process of bronze refinery. Sample 4 is confirmed as a lump of bronze which is one of Cu-Sn-Pb system from alloy of tin and lead into pure bronze. It is believed that the third building site at Neungsan-ri temple site in Buyeo produced bronze matte by refinery of copper ore or produced low-quality bronze by melting matte imported from outside.