• Journal of the Korea Institute of Building Construction
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• v.21 no.4
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• pp.293-303
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• 2021

The void PC slab has a structurally reasonable cross-section by forming the hollow section of the neutral axis that is unnecessary for bending behavior. Domestic PC factories have introduced automation equipment to produce hollow PC slabs, and are achieving hollow sections through inserts. However, since the excessive initial investment cost of the PC factory is the main factor in the increase in production cost, other alternatives are needed. Therefore, in this study, when producing hollow PC slab members, by using a rubber tube as a formwork to form an internal hollow space, it is intended to contribute to securing productivity through molding various hollow shapes, making it larger, lightweight, and enabling rapid production. To implement a hollow PC slab using a rubber tube mold, the shape of a hollow cross-section in which the tube is combined was implemented by considering the shape of the rubber tube first. In addition, to secure the concrete quality of the hollow part, the finish properties of the rubber tube mold and concrete were evaluated, and the hollow PC production process was established.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.968-973
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• 2005

The purpose of this study is to clarify the reality of labor and capital productivity in the construction industry through an industry-level approach and to analyze the relationship between labor and capital productivity using a Cobb-Douglas production function. According to the research results, the construction industry has shown a very high capital productivity, while labor productivity has kept up a low level during the 1980s and 1990s. The reason was because of the lack of skillful construction workers and the decrease of capital. Meanwhile, the construction productivity has greatly increased since 2000 when there was no change in wages. This was because of a large inflow of low-wage foreign workers while the amount of value added has dramatically increased due to the liberalized sale price of apartment buildings. According to the analysis by the Cobb-Douglas production function, the elasticity coefficient of V/L to K/L in the construction industry had decreased from 1.1663 in the 1^st period(1971-1988) to 0.4465 in the 2^nd period(1989-1997), and to 0.1664 in the 3^rd period(1998-2003). Such a result means that the allocation of labor has gradually increased while the allocation of capital has decreased. Moreover there was a big increase in allocation of labor after 1998 due to the excessive deterioration of capital. In conclusion, in order to raise the construction productivity and to avoid labor-intensive production methods, investment for capital should be more increased. In particular, new machinery and equipment that can actually substitute human labor in construction sites should be more developed and applied to construction sites.

• Clean Technology
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• v.15 no.2
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• pp.137-145
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• 2009

In this study, Austrian cleaner production program, ECOPROFIT, was introduced to 15 companies in Korea. The performance and the proposed options of the program were compared with those of Austria. Various options such as good housekeeping, process changes, internal/external recycling, substitution of raw materials were suggested for domestic companies. There are something in common between Korea and Austria such as no relation between company sizes and derived options and good housekeeping as a major option. The difference is that 1.9 years of recovery period on investment is required in Korea, while only 0.5 year is required in Austria. The reason for not applying the suggestions was due to the priority of the company policies in Korea, but was due to the technical problems in Austria. To activate the cleaner production in the Korean regional industry, more systematic analysis on the examples and performances as well as additional studies to disseminate informations and the best practices are necessary.

• The Journal of the Korea Contents Association
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• v.8 no.12
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• pp.98-108
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• 2008

The recent growth of the national film and broadcasting industry and the international success of korean films and dramas have resulted in enlarging the financial investment of overall film and drama producing system. Many of local governments contend in the inducement of the drama and movie production because building a drama or movie set help to grow the local business. However, the effort of local governments has rarely achieved the long-term effect. The purpose of this paper is to examine the successful examples of the local specialization as drama or movie set, to compare them with other countries, and to analyze the systematic cause of their success. Moreover, this paper tries to suggest few principles to preplan the successful inducement, to increase the positive outcome, and to invigorate the local area.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.07a
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• pp.271-272
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• 2016

Owing to the development of information communication technology(ICT), there are many changes taking place in the agriculture sector. As an example, an effective agricultural activities with ICT have brought an increase in agricultural production. On the other hand, these technology investment activities are very costly. Until recently, the technology development has been made in agricultural technology development perspective. This view, however, has been changed to production increase in accordance with the crop growth conditions. In this paper, we propose a device which can maintain an optimal crop growing environment. It is economic by utilizing the existing facility of farmhouse and can reduce the cost of crop growth environment improvement.

• World Technopolis Review
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• v.4 no.2
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• pp.79-86
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• 2015

Over the last two decades, interest increased with regard to how some research universities made direct impacts on surrounding regional economic activities and growth. Although the role of basic research for most research universities has remained strong, pressure has intensified to broaden its missions to include helping local and regional economic development efforts. Consequently, many research universities have evolved their basic scientific research mission from the production of scientific knowledge to the sharing and exchange of knowledge with local industries by actively engaging in local economic development (Uyarra 2010). Previous examination has shown that most research universities contribute to local and regional economic development by various functions they provide. They are as follows: Creation of Knowledge, Human-capital creation, Transfer of existing know-how, Technological innovation, Capital investment, Regional leadership, Knowledge infrastructure production and Influence in regional milieu (Drucker and Goldstein 2007). This paper will review the existing literature on the role of universities and its impacts on local regional economic growth and development. In addition, this paper will show how two major research universities (The University of Arizona and Arizona State University) have contributed to the growth of Arizona during last two decades. It is believed that the existence of these two research universities have been instrumental in making industries more diverse and highly attractive, particularly in the Phoenix Metropolitan Area.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.190.1-190.1
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• 2015

Graphite has excellent mechanical and physical properties. It is known to advanced materials and is used to materials for molds, thermal treatment of furnace, sinter of diamond and cemented carbide tool etc. SiC materials are coated on the surface and holes of graphite to protect particles emitted from porous graphite with 5%~20% porosity and make graphite hard surface. SiC materials have high durability and thermal stability. Thermal CVD method is widely used to manufacture SiC thin films but high cost of machine investment and production are required. SiC thin films manufactured by Si reaction liquid and vapore with carbon are effective because of low cost of machine and production. SiC thin films made by vapor silicon infiltration into porous graphite can be obtained for shorter time than liquid silicon. Si materials are evaporated to the graphite surface in about $10^{-2}$ torr and high temperature. Si materials are melted in $1410^{\circ}C$. Si vapor is infiltrated into the surface hole of porous graphite and $Si_xC_y$ compound is made. $Si_x$ component is proportional to the Si vapor concentration. Si diffusion coefficient is estimated from quadratic equation obtained by Fick's second law. The steady stae is assumed. Si concentration variation for the depth from graphite surface is fitted to quadratic equation. Diffusion coefficient of Si vapor is estimated at about $10^{-8}cm^2s^{-1}$.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.12
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• pp.142-150
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• 1996

Nowadays, as the development paeiod of new products becomes even shorter, the importance of Rapid Prototyping Technology(RPT) has been rapidly increased. The major application of RPT is an early verification of product designs and quick production of prototypes for testing. Moreover, RPT is applied not only as a second tooling process such as mold making and investment casting but also as a creating some physical structure in medical field. Despite the remarkable progress of RPT, it is required to improve various problems resulting from application such as production time, accuracy and materials. This paper presents a laser scan path generation for accuracy of stereolithographicparts The methodology of laser scan path generation is discussed based on the stereolithography, The procedure of this research is as follows : 1) Input laser scanning conditions such as a laser beam diameter and a laser scanning interval, 2) Reconstruct original contours without self intersecting offset, 3) Calculate offset about reconstructed contours, 4) Calculate intersection points between horizontal or vertical lines and offset contours for internal hatch, 5) Decide laser shutter on/off points. The algorithm developed and programmed by C language is verified as an efficient method after testing a number of STL files of mechanical parts.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.337-342
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• 2015

The company of 4 core materials that are needed for photovoltaic generation is located in area around this university in Gunsan, Saemangeum. And also, it was almost completed the value chain about the production of Polysilicon, Ingot, Wafer, modules and the design, construction of generation system. The industry-academy-government has understood that because of the relative companies' production and investment, it leads to a supply and demand of manpower and thus will have field centered manpower education. This program will help the problem of lack of manpower in relative companies by establishing competitive major agreement like vocational education system. Also, the university and the participating company in joint have pushed ahead field business education to make the least of industrial-education's mismatch, the training of professional manpower connected with related industries to make the universities chemical characteristics, companies securing excellent manpower and contributed to the revitalization of the regional economy. In this paper, are aware that photovoltaic industry is a future strategic industry for the country, so we will train the immediately site adapting manpower for the area of photovoltaic material and system as our goal. This is shown results of education operation for 4 years.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.5
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• pp.481-491
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• 2014

In this paper, we discussed a problem for improving the throughput of a crankshaft manufacturing line in an automotive factory in which the budget for purchasing new machines and installing additional buffers is limited. We also considered the constraint of available space for both of machine and buffer. Although this problem seems like a kind of buffer allocation problem, it is different from buffer allocation problem because additional machines are also considered. Thus, it is not easy to calculate the throughput by mathematical model, and therefore simulation model was developed using $ARENA^{(R)}$ for estimating throughput. To determine the investment plan, a modified Arrow Assignment Rule under some constraints was suggested and it was applied to the real case.