• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.207-209
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• 2011

Numerous reports show that alternative project delivery systems (PDSs) such as design-build (DB), construction management at risk (CMR), and design-build-maintain (DBM) are increasingly used in many countries. This study compared characteristics of each PDS (design-bid-build (DBB), DB, CMR, or DBM) by analyzing quantitative data from 9 research articles. In order to compare characteristics between DBB and alternative PDSs, the study is based on principal 3 factors - Time, Cost, and Quality. DB shows the best performance in the time part and also the cost performance depending on facility type and project size. The performance of quality has minor difference among different PDSs. These results support the fact that using an appropriate PDS by the characteristic of a project makes high value of efficiency and productivity.

• Smart Structures and Systems
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• v.9 no.3
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• pp.207-230
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• 2012

Full-scale shake table seismic experiments and low-amplitude vibration tests on a masonry building are carried out to assess its seismic performance as well as study the effectiveness of a new multifunctional textile material for retrofitting masonry structures against earthquakes. The un-reinforced and the retrofitted with glass fiber reinforced polymer (GFRP) strips masonry building was subjected to a series of earthquake excitations of increasing magnitude in order to progressively induce various small, moderate and severe levels of damage to the masonry walls. The performance of the original and retrofitted building states is evaluated. Changes in the dynamic characteristics (lowest four modal frequencies and damping ratios) of the building are used to assess and quantify the damage states of the masonry walls. For this, the dynamic modal characteristics of the structure states after each earthquake event were estimated by performing low-amplitude impulse hammer and sine-sweep forced vibration tests. Comparisons between the modal results calculated using traditional accelerometers and those using Fiber Bragg Grating (FBG) sensors embedded in the reinforcing textile were carried on to investigate the reliability and accuracy of FBG sensors in tracking the dynamic behaviour of the building. The retrofitting actions restored the stiffness characteristics of the reinforced masonry structure to the levels of the original undamaged un-reinforced structure. The results show that despite a similar dynamic behavior identified, corresponding to reduction of the modal frequencies, the un-reinforced masonry building was severely damaged, while the reinforced masonry building was able to withstand, without visual damage, the induced strong seismic excitations. The applied GFRP reinforcement architecture for one storey buildings was experimentally proven reliable for the most severe earthquake accelerations. It was easily placed in a short time and it is a cost effective solution (covering only 20% of the external wall surfaces) when compared to the cost for full wall coverage by GFRPs.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.207-207
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• 2011

Amorphous transparent oxide semiconductors (a-TOS) have been widely studied for many optoelectronic devices such as AM-OLED (active-matrix organic light emitting diodes). Recently, Nomura et al. demonstrated high performance amorphous IGZO (In-Ga-Zn-O) TFTs.1 Despite the amorphous structure, due to the conduction band minimum (CBM) that made of spherically extended s-orbitals of the constituent metals, an a-IGZO TFT shows high mobility.2,3 But IGZO films contain high cost rare metals. Therefore, we need to investigate the alternatives. Because Aluminum has a high bond enthalpy with oxygen atom and Alumina has a high lattice energy, we try to replace Gallium with Aluminum that is high reserve low cost material. In this study, we focused on the electrical properties of IZO:Al thin films as a channel layer of TFTs. IZO:Al were deposited on unheated non-alkali glass substrates (5 cm ${\times}$ 5 cm) by magnetron co-sputtering system with two cathodes equipped with IZO target and Al target, respectively. The sintered ceramic IZO disc (3 inch ${\phi}$, 5 mm t) and metal Al target (3 inch ${\phi}$, 5 mm t) are used for deposition. The O2 gas was used as the reactive gas to control carrier concentration and mobility. Deposition was carried out under various sputtering conditions to investigate the effect of sputtering process on the characteristics of IZO:Al thin films. Correlation between sputtering factors and electronic properties of the film will be discussed in detail.

• Journal of the Korea Institute of Building Construction
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• v.15 no.2
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• pp.209-215
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• 2015

This study was conducted to analyze the actual utilization rate of the deposit for defect repair of apartment complexes and its influential factors. We analyzed the data on enforced defect deposit cases by using one-sample t-test, Pearson's correlation analysis, and simple linear regression analysis. The difference between the deposit amount specified and the enforcement amount actually disbursed was found to about 0.51%. The change rates for short-term costs amounted approximately to $839KRW/m^2$ and 130,000 KRW/household per year, and those for long-term costs were $647KRW/m^2$ and 123,207 KRW/household per year. The results warrant the need for further research on establishing a deposit amount based on actual statistical data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.207-208
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• 2016

By according to increase the research for autonomous vehicle in automobile industries, the efficient of autonomous cargo truck instead of conventional driver cargo truck will be analyzed in logistics areas. The inland transportation has been serious problem such as traffic accident, traffic congestion in downtown, air pollution, noise and etc. even if it have a great effect to logistics industries. Especially there have to be improved its transportation schedule and sleepy driving in night which induced heavy accident in highway. In this study, the effectiveness of autonomous cargo truck will be analysed by considering the logistics cost including social effects.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.207-208
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• 2023

The procedure of predicting the construction cost and selecting the best alternative is performed based on comparative review of each building case. In the case of office building, it is required continuously until design is complete, since the owner requirements are various and likely to change during the design process compared to a standardized apartment. However, since the comparison work for each alternative in practice uses only the unit construction cost, there is no correlation between the alternative and the final result, and it is difficult to quantitatively determine the effect of the determined design factor on the total construction cost. It is needed that a means to support the generation of design alternatives using similar building cases during the design phase. This paper proposes a BIM-based data replacing process to support creating and comparison of design alternatives of internal finishing for office building. When design alternatives are created through the proposed process, it is possible to compare several similar cases with current project under equivalent design circumstance. Because only some finishing properties are replaced while maintaining the shape information such as the length, height, and base constraint of the object to be replaced.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.207-211
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• 2008

The importance of cost management in early stage has been increasing due to market change and competition severence in construction industry. Because the adjustable budget is only 20% after finishing design stage, the critical decision is made in the early stage. However, in the early stage, the design information is not enough to make crucial decision. Therefore, this research suggests the predicting method on the purpose of accurate cost estimation. The parametric estimation is appropriate for the early stage, especially it has the strength of rapidity in cost estimation. This research analyzes 84 actual data of public apartment on the scale of $11{\sim}15$ stories, and then performs the correlation analysis between cost and influence factors. After eliminating the parameters which causes the problem of multicollinearity, this research derived the formula through the multi-regression analysis.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.4
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• pp.207-223
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• 2015

In this paper a method for simultaneous swift non-linear analysis and optimal design/posture of mechanical/biomechanical systems is presented. The method is developed to get advantages of iterations in non-linear analysis and/or generations in genetic algorithm (GA) for the purpose of efficient analysis within the optimal design/posture. The method is applicable for both size and geometry optimizations wherein material and geometry non-linearity are present. In addition to established mechanical systems, the method can solve biomechanical models of human musculoskeletal system. Optimization-based procedures are popular methods for resolving the redundancy at joints wherein the number of unknown muscle forces is far more than the number of equilibrium equations. These procedures involve optimization of a cost function(s) which is assumed to be consistent with the central nervous system's strategy when activating muscles to assure equilibrium. However, because of the complexity of biomechanical problems (i.e., due to non-linear biomaterial, large deformation, redundancy of the problem and so on) efficient analysis are required within optimization procedures as suggested in this paper.

• The Journal of Information Systems
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• v.17 no.4
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• pp.207-232
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• 2008

As electronic commerce is growing to be a part of everyday business life for companies, enterprises are required to establish the appropriate strategy to effectively realize their business visions. The correct choice of strategy enables organizations to make efficient use of internal resources and adjust to the external environment, affecting their performance. The nature of the firms' strategy has been currently focused on the new business model such as e-commerce. In the beginning of e-commerce, the decreasing cost of business transactions was a major benefit affecting its success. However, e-commerce firms are currently facing new advanced information technology, various business models and serious competition. To deal with these new challenges, there is an increasing demand for right strategy direction to effectively and efficiently manage a corporation's internal resources and external environments that are related to electronic commerce. Moreover, it is necessary both to set up the feasible strategy direction and to evaluate its outcome. The purpose of this study attempts to provide appropriate e-commerce strategy, which is well matched with e-commerce performance, as the different strategies affect different results of e-commerce. On the basis of the results of this research, we can see that the strategies selected by e-commerce companies differ according to the e-commerce type and firm's size.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.207-207
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• 2010

Both ZnO and GaN have excellent physical properties in optoelectronic devices such as blue light emitting diode (LED), blue laser diode (LD), and ultra-violet (UV) detector. The ZnO/GaN heterostructure, which has a potential to achieve the cost efficient LED technology, has been fabricated by using radio frequency (RF) sputtering, pyrolysis, metal organic chemical vapor deposition (MOCVD), direct current (DC) arc plasmatron, and pulsed laser deposition (PLD) methods. Among them, the PLD system has a benefit to control the composition ratio of the grown film from the mixture target. A 500-nm-thick ZnO film was grown by PLD technique on c-plane GaN/sapphire substrates. The post annealing process was executed at some varied temperature between from $300^{\circ}C$ to $900^{\circ}C$. The morphology and crystal structural properties obtained by using atomic force microscope (AFM) and x-ray diffraction (XRD) showed that the crystal quality of ZnO thin films can be improved as increasing the annealing temperature. We will discuss the post-treatment effect on film quality (uniformity and reliability) of ZnO/GaN heterostructures.