• Environmental and Resource Economics Review
• /
• v.10 no.2
• /
• pp.217-234
• /
• 2001

The use of district heating is expanding very rapidly in Korea. High population densities and the relatively cold winters make district heating an economically attractive option. About 8 percent of Korean houses are already using district heating and the government is seeking to aggressively expand this number. It has set a target of 15 percent of the residential heat market to be met by district heating in the year 2001. The main purpose of this paper is to analyze the consumption behavior of households using district heating. By pooling time-series and cross-sectional data for 12 apartment complexes in Seoul area, a single demand function is estimated and used to forecast the amounts of heat demanded by the individual households. The results shows that the level of consumption varies among households, depending on the non-economic factors such as the installation of individual metering equipment and the volume of apartment building. When individual metering equipment is installed, the level of annual heat consumption per household declines, on average, about 22.1 Mcal per square meters, which is equivalent to 834 won per square meter in terms of heating expenditures. In case that the apartment building was built in more than 6 stories, annual consumption level reduces additionally about 17.3 Mcal per square meters and, thus, save the expenditures by 649 Won per square meters, compared to the opposite case.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2006.11a
• /
• pp.123-126
• /
• 2006

Existing Deck Plate for a one of system forms, there is various advantage and application actual results increasing rapidly. But design of deck is depending on engineering data collections or design data on deck manufacture ordinarily. When construct, is responsible for deflection occurrence, And Because confirmation of crack occurrence region is impossible, there is difficulty of repair, reinforcement about crack and water leakage. According to got following conclusion as result that economic performance, preservation administration and repair reinforcement develops easy using steel truss snap tie by wedge pin on coating plywood that is slab Panel Wood System Form method of construction there is Deck Plate's advantage. (1) In stab lower part is exposed disjointing in which a criminal is fastened to be interrogated after construction acceptance and repair, reinforcement of crack is possible (2) Construction cost curtailment effect of about 29.2% than conventional type and about 10% than deck plate (3) Construction period reduction of about 3 day than conventional type and about 0.3 day than deck plate (4) Labor curtailment effect more than about $29{\sim}50%$ from conventional type

• Journal of the Korean Professional Engineers Association
• /
• v.27 no.1
• /
• pp.5-12
• /
• 1994

In the high degree information society of the 21st century, along with the social activity becoming much more closer, our life style will also be very much changed. Recognition for obtaining various informations rapidly will be anticipated to enhance and the progress of a mobile communication system is greatly expected. This will enable the system to give and receive ″whenever, wherever, whomever, whatsever information.″ In our country, the car telephone and personal mobile communication services of radio calling etc. are diversified by the telecommunication system reformation and by the introduction of competive principle of the hereafter of 1988. Moreover, in accordance with the tariff, the number of subscrier is rapidly increasing. On the other hand, on the utility side of business, for the realization of a mobile communication which is abundant in functional nature, not only the hitherto voice but also non voice system of data communication is being introduced. The Ministry of Communications of Korea has been expediting the effective utilization of limited frequency band of qusai microwave band etc. as a concrete measures for an ever increasing demand. At the same time, to disseminate and promote a mobile communication most effectively, convenience, economic, and safety nature of the system, and in addition to these, international standardization is considered. For constitution of a new mobile communication, the Ministry has been promoting various policies designed for the digitalization of system, utility extention for home. personal level.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.458-461
• /
• 2009

In 3-phase 4 wire system, appearance of the $3^{rd}$ harmonic current by increasing non-liner load is the one of causes overheating neutral wire of power line, and apparatus. So it is necessary to protect power-factor decreasing by the $3^{rd}$ harmonic, and electric power apparatus, and line safely, in this study, power system accidents caused by the $3^{rd}$ harmonic were investigated, then harmonic components analysis and unbalanced load analysis got accomplished. As result, we proposed the method to protect the power line and apparatus from over-current of neutral line by using the most economic 4-pole low voltage circuit breaker.

• Journal of the Korean Geosynthetics Society
• /
• v.13 no.4
• /
• pp.153-159
• /
• 2014

During the winter and spring seasons in Korea, structures such as buried water supply pipelines, roads, railways are frequently damaged due to frost heaving and thawing. Until now, the method of substituting the frost susceptible soil with the gravel or rubbles those are non-frost susceptible materials have been employed in Korea to prevent frost heaving. A series of laboratory soil tests and indoor frozen soil engineering experiments, as well as laboratory frost heaving tests were conducted for seeking the means of utilizing recycled PET bottles as substitute material.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.10
• /
• pp.57-64
• /
• 2021

In the last decade, the effect of digitalization was the most cited issue in economic discourse, especially since technological advances, automation, and artificial intelligence are the key to the future discussions. Unemployment is one of the most important and continuous debates, especially in times of crisis due to the COVID-19 pandemic. Therefore, this study aims to analyze the influence of leadership style in innovation organizations to deal with the crisis. In this study, a non-probability purposive sampling method was used. A total of 377 respondents were from LinkedIn social media in Indonesia, with the criteria of employees who have worked for at least 6 years. The structural equation model was analyzed with Amos 25.0. The results show that virtual, servant, and transformational leadership influence employee creativity. Moreover, employee creativity strongly influences organizational innovation; therefore, a new model was found to meet the challenges during the COVID-19 pandemic crisis, which is leadership. Therefore, these results are useful for managers to overcome challenges during the COVID-19 pandemic crisis to manage employee creativity for a better innovative organization and make science a reference for finding solutions to the global wave of unemployment in the revolution 5.0 era.

• Nuclear Engineering and Technology
• /
• v.53 no.9
• /
• pp.2926-2936
• /
• 2021

Rare-earth (RE) industries generate a massive amount of radioactive residue containing high thorium concentrations. Due to the fact that thorium is considered a non-economic element, large volume of these RE processed residues are commonly disposed of without treatment. It is essential to study an appropriate treatment that could reduce the volume of waste for final disposition. To this end, this research investigates the applicability of carbon-based adsorbent in separating thorium from aqueous phase sulphate is obtained from the cracking and leaching process of solid rare-earth by-product residue. Adsorption of thorium from the aqueous phase sulphate by carbon-based electrodes was investigated through electrosorption experiments conducted at a duration of 180 minutes with a positive potential variable range of +0.2V to +0.6V (vs. Ag/AgCl). Through this research, the specific capacity obtained was equivalent to 1.0 to 5.14 mg-Th/g-Carbon. Furthermore, electrosorption of thorium ions from aqueous phase sulphate is found to be most favorable at a higher positive potential of +0.6V (vs. Ag/AgCl). This study's findings elucidate the removal of thorium from the rare-earth residue by carbon-based electrodes and simultaneously its potential to reduce disposal waste of untreated residue.

• Architectural research
• /
• v.21 no.1
• /
• pp.1-8
• /
• 2019

Social housing has a long history in Germany from the first still existing social housing ever, the "Fuggerei" in Augsburg (founded in 1521), over the last 100 years from the end of World War I to today's situation where the need in social housing has increased while the number of housing projects and the number of existing apartments in this program has decreased or ended. Socio-economic changes like demographic evolution, more single households, greater working abilities in bigger cities and an unforeseen highly increased number of migrants within Europe mostly but also from other countries led to the need of affordable housing for a growing number of people who are not able to care for their housing needs in their own responsibility. This is especially true for bigger cities, where the offer of affordable housing is nearly non-existing any more. The family Fugger, a trade and banking dynasty at their time, established a very modern housing concept, providing good and healthy living space for their workers. In 2018 now some trade companies, discounters (ALDI, LIDL, Norma) and IKEA announce to combine their interest in sales in the inner cities with the municipal interest of redensification of existing housing areas and conversion to ecological urban reconstructuring.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.7
• /
• pp.131-143
• /
• 2023

In the future knowledge society, the importance of business data is expected to increase, and it is recognized as a raw material for companies to manufacture product or develop service. As the importance of data increases, methods to calculate the economic value of database assets is being studied. There are many studies to evaluate the value of database assets, but the characteristics of database assets are not fully reflected. In this study, we classified database assets into revenue-type, non-revenue-type, and public-type database assets by considering the characteristics of database assets. In addition, focusing on the fact that revenue-type database assets can be valued similarly to existing technology valuation, we developed a method for calculating the life of database assets that includes risk-adjusted discount rate.

• Earthquakes and Structures
• /
• v.23 no.4
• /
• pp.339-352
• /
• 2022

Due to the large volume and generally as a public building, the damage of large-span space structures under various non-conventional loads will cause greater economic losses, casualties, and social impacts, etc. Therefore, it is particularly important to evaluate the seismic performance of large-span space structures. This paper taked a multipurpose sports center as an example and considered its synergistic deformation based on the method of equivalent damping ratio. Furthermore, The ABAQUS software was used to analyze the time-history and energy response of the multipurpose sports center under the action of rare earthquakes, and proposed a quantitative damage index to assess the overall damage of the structure. Finally, the research results indicated that the maximum inter-story drift ratio of the multipurpose sports center under the action of rare earthquakes was less than its limit value. The frame beams presented different degrees of damage, but the key members were basically in an elastic state. The bearing capacity did not reach the limit value, which satisfied the intended seismic performance target. This study taked an actual case as an example and proposed a relevant damage evaluation system, which provided some reference for the analysis of the seismic performance of large-span space structures.