• School Mathematics
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• v.4 no.4
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• pp.601-615
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• 2002

This paper analyzed <7-나> and <8-나> textbooks and teacher instruction activities in classrooms, focusing on procedures used to solve construction problems. The analysis of the teachers' instruction and organization of the construction unit in <7-나> textbooks showed that the majority of the textbooks focused on the second step, i.e., the constructive step. Of the four steps for solving construction problems, teachers placed the most emphasis on the constructive order. The result of the analysis of <8-나> textbooks showed that a large number of textbooks explained the meaning of theorems that were to be proved, and that teachers demonstrated new terms by using a paper-folding activities, but there were no textbooks that tried to prove theorems through the process of construction. Here are two alternative suggestions for teaching strategies related to the construction step, a crucial means of connecting intuitive geometry with formal geometry. First, it is necessary to teach the four steps for solving construction problems in a practical manner and to divide instruction time evenly among the <7-나> textbooks' construction units. The four steps are analysis, construction, verification, and reflection. Second, it is necessary to understand the nature of geometrical figures involved before proving the problems and introducing the construction part as a tool for conjecture upon theorems used in <8-나> textbooks' demonstrative geometry units.

• The Korean Journal of Health Service Management
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• v.5 no.3
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• pp.101-110
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• 2011

This study analyzed affecting factors of employees working at dental hospitals to the organizational commitment and service quality, and then tried to utilize it as a basic data in executing personnel training policies for dental hospital's practitioners. The survey was conducted from July 1st to July 30th, 2010, and used 193 copies for this research analysis. As a hypothetical verification result through regression analysis, means and capabilities among empowerment factors influenced significant positive (+) effects, and self-determination and influences did not make significant effects. Also, organization commitment was displayed as influencing significant positive (+) effects to the service quality. When considering this research's results as a basement, an alternative for the managerial innovation shall be established for promoting mutual developments of individuals and organization in midst of promptly changing economic environments. That is, a personal training system has to be set up in which more decision-making rights on given assignments of dental hospital's employments are endowed, and then responsibilities are directed to be charged so much by introducing the empowerment concept instead of the managerial technique centering on controls.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.2
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• pp.101-113
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• 2011

As information and communication technology advances driving the rapid evolution of e-commerce and e-business becomes on effective marketing means for both business and institutions, the industry deals with these changes and has a profound, positive impact on production and operations management. But the construction industry falls behind compared with other industries in productivity, informationalization, automatization and globalization. Especially even though the informationalization is inevitable in any developing society, a number of construction industries can hardly cope with it properly. As the construction industry gets informationalized and advanced, the introduction of PMIS (Project Management Information System) is making progress actively for the effective construction project control and productivity improvement in construction. With the government officials' political promotion and the rising desire for construction informationalization of enterprises, many are attempting to develop integrated systems or to replace a previous system with a more advanced alternative. Construction Industry, however, has the peculiar properties that the period for the completion of construction is limited and on top of that, most of its data processing systems are seen as being an early stage in the design of management information systems. As a result, there are extremely few applications in the construction industry. In this paper, we propose the PMIS system based on new model 4CM that improves on previous models.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.191-199
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• 1999

This study evaluated the availability as an alternative adsorbent which is cheaper and more efficient than CuO/${\gamma}$-$Al_2O_3$ which have been studing vigorously to remove $SO_2$. Five adsorbents (CuO/${\gamma}$-$Al_2O_3$, Iron ore, Slag, LD slag, $Fe_2O_3$) was employed in a fixed bed reactor. $SO_2$ breakthrough curves were obtained as a function of temperature, initial gas velocity and particle size. Saturation capacities calculated by the numerical integration of breakthrough curves of $SO_2$ increased with increasing reaction temperature. $SO_2$ breakthrough curve equation of $Fe_2O_3$ for this system can be expressed as Kr=3,914,000 exp(-37,329.86/RT). By means of the breakthrough curve, the influence of bed height on breakthrough time was also estimated.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.359-362
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• 2001

Most old apartment housing have been replaced with new ones by means of the reconstruction. But with the change of the construction environment, remodeling is introduced as a new alternative for the replacement. Remodeling is expected to reduce national loss owing to the early reconstruction of old apartments resulted from economical and functional deterioration. But there still remains a lot of problems to be first solved for Remodeling. One of those is to figure out how to perform an economic feasibility analysis effectively. The researches of remodeling done under the rally stage are not sufficient in economic feasibility for apartment housing. Therefore, this paper suggests an effective method for the economic evaluation of remodeling projects focusing on a rental high-rise apartment.

• Transactions on Electrical and Electronic Materials
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• v.11 no.4
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• pp.174-177
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• 2010

We have developed an environment-friendly etching process, an alternative to the dichromic acid etching process, as a pretreatment of acrylonitrile-butadiene-styrene (ABS) plastic for electroless plating. In order to plate ABS plastic in an electroless way, there should be fine holes on the surface of the ABS plastic to enhance mechanically the adhesion strength between the plastic surface and the plate. To make these holes, the surface was coated uniformly with dispersed chemical foaming agents in a mixture of environmentally friendly dispersant and solvent by the methods of dipping or direct application. The solvent seeps into just below the surface and distributes the chemical foaming agents uniformly beneath the surface. After drying off the surface, the surface was heated at a temperature well below the glass transition temperature of ABS plastic. By pyrolysis, the chemical foaming agents made fine holes on the surface. In order to discover optimum conditions for the formation of fine holes, the mixing ratio of the solvent, the dispersant and the chemical foaming agent were controlled. After the etching process, the surface was plated with nickel. We tested the adhesion strength between the ABS plastic and nickel plate by the cross-cutting method. The surface morphologies of the ABS plastic before and after the etching process were observed by means of a scanning electron microscope.

• Structural Engineering and Mechanics
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• v.13 no.5
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• pp.543-556
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• 2002

A dynamic elastic local buckling analysis is presented for a pile subjected to an axial impact load. The pile is assumed to be geometrically perfect. The interactions between the pile and the surrounding soil are taken into account. The interactions include the normal pressure and skin friction on the surface of the pile due to the resistance of the soil. The analysis also includes the influence of the propagation of stress waves through the length of the pile to the distance at which buckling is initiated and the mass of the pile. A perturbation technique is used to determine the critical buckling length and the associated critical time. As a special case, the explicit expression for the buckling length of a pile is obtained without considering soil resistance and compared with the one obtained for a column by means of an alternative method. Numerical results obtained show good agreement with the experimental results. The effects of the normal pressure and the skin friction due to the surrounding soil, self-weight, stiffness and geometric dimension of the cross section on the critical buckling length are discussed. The sudden change of buckling modes is further considered to show the 'snap-through' phenomenon occurring as a result of stress wave propagation.

• Earthquakes and Structures
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• v.1 no.4
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• pp.391-410
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• 2010

There are several important considerations that need to be made in the capacity design of RC frame-wall structures. Capacity design forces will be affected by material overstrength, higher mode effects and secondary loadpaths associated with the 3-dimensional structural response. In this paper, the main issues are identified and different means of predicting capacity design forces are reviewed. In order to ensure that RC frame-wall structures perform well it is explained that the prediction of the peak shears and moments that develop in the walls is particularly important and unfortunately very challenging. Through examination of a number of case study structures it is shown that there are a number of serious limitations with capacity design procedures included in current codes. The basis and potential of alternative capacity design procedures available in the literature is reviewed, and a new simplified capacity design possibility is proposed. Comparison with the results of 200 NLTH analyses of frame-wall structures ranging from 4 to 20 storeys suggest that the new method is able to predict wall base shears and mid-height wall moments reliably. However, efforts are also made to highlight the uncertainty with capacity design procedures and emphasise the need for future research on the subject.

• Journal of the Semiconductor & Display Technology
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• v.5 no.3 s.16
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• pp.5-10
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• 2006

This paper investigates cutting qualities after laser dicing and predicts the problems that can be generated by laser dicing. And through 3 point bending test, die strength is measured and the die strength after laser dicing is compared with the die strength after mechanical sawing. Laser dicing is chiefly considered as an alternative to overcome the defects of mechanical sawing such as chipping on the surface and crack on the back side. Laser micromachining is based on the thermal ablation and evaporation mechanism. As a result of laser dicing experiments, debris on the surface of wafer is observed. To eliminate the debris and protect the surface, an experiment is done using a water soluble coating material and ultrasonic. The consequence is that most of debris is removed. But there are some residues around the cutting line. Unlike mechanical sawing, chipping on the surface and crack on the back side is not observed. The cross section of cutting line by laser dicing is rough as compared with that by mechanical sawing. But micro crack can not be seen. Micro crack reduces die strength. To measure this, 3 point bending test is done. The die strength after laser dicing decreases to a half of the die strength after mechanical sawing. This means that die cracking during package assembly can occur.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1279-1284
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• 2008

The alternative energy has lately attracted considerable attention due to the high oil price and environment problem. Deep sea water that is one of the natural energy sources should be getting popular continually to reduce the environment problem. In this study, cooling system of deep sea water using heat exchangers of two hotels where is located in near Hae-undae Bay has been analyzed on the quantity of electricity comparison between existing cooling system and deep seawater cooling system. As shortly, the results of study showed that the first building approximately saves 370 millions won per year, also the second building saves 248 millions won per year. It means that the cooling system by using deep sea water has great worth to reduce the ratio of fossil fuel.