• Journal of Applied Reliability
• /
• v.8 no.3
• /
• pp.135-144
• /
• 2008

The economic life for three types of military wheeled vehicles with load capacities of 1/4, $1{\cdot}1/4$, and $2{\cdot}1/2$ tones has been evaluated on the basis of the equivalent acquisition and operating costs. The economic life of wheeled vehicles were calculated from 12 to 18 years by using the annual equivalent cost method. The equivalent cost was decided at the lowest point of the total amount of equivalent acquisition cost and operating cost. The operating cost were collected from the field data. The evaluated economic life can be very useful for deciding the total life cycle of these three types of military vehicles. The annual equivalent cost method may be also applied to other military equipments such as communication electronics, weapon systems, and other type of vehicles.

• Korean Journal of Construction Engineering and Management
• /
• v.6 no.2 s.24
• /
• pp.129-138
• /
• 2005

The purpose of this study is to assess economic effects for an advanced technology-based HVAC system. The study has been performed using LCC technique for the economic analysis. Data for LCC analysis are collected from estimation and interview of estimators and maintenance experts of buildings. Based on the LCC analysis, the economic effect of a new HVAC system has been predicted as follows : for the investment during 15 years of study period, (1) $21.6\%$ of LCC saving is predicted, (2) return rate for the investment is 4.8 times in case of new construction, and 14.4 times in case of building remodelling.

• Applied Chemistry for Engineering
• /
• v.34 no.3
• /
• pp.291-298
• /
• 2023

This research evaluates the sustainability of gasifying livestock manure to produce fuel gas from an economic and carbon emission perspective. The entire process, including gasification, fuel gas purification, and pipeline installation to transport the produced fuel gas to the demanding industrial complex, is analyzed for realistic feasibility. The study is conducted using an ASPEN PLUS simulation with experimental data. The results of the economic and CO₂ life cycle assessments confirm that the fuel gas produced from livestock manure is competitive with natural gas despite having a lower calorific value. When used as a fuel with a high hydrogen content, the fuel gas emits less CO₂ per calorific value, making it more environmentally friendly. A scenario analysis is also performed to determine the expected economics, with price competitiveness being influenced by several factors. Although a significant decrease in natural gas prices could reduce the price competitiveness of the proposed process, it can still be supported by government policies. The cash flow analysis also confirms the economic viability of the process.

• Korean Journal of Construction Engineering and Management
• /
• v.16 no.5
• /
• pp.12-20
• /
• 2015

Construction industry pays attention to modular construction recently which based on factory production not on labor intensive site production. Since modular construction has high time shortening effect and easiness of demolition and recycling, it has been applied to the temporary residential building. Domestic modular construction market are not activated yet, however, due to the high initial cost to realize modular construction. This study proposes demand-sensitized movable modular building in order to reduce the financial burden. The study compares between RC method building and Modular building which moves building when the demand falls off from Life-Cycle Cost's viewpoint. As a result of the economical evaluation, RC method achieved profits faster than Modular model, but Modular model's gross earnings during the life-cycle are much bigger than RC method. In other words, the result means that the market-sensitized movement of the modular building would be an economci choice in Life-Cycle Costing aspect.

• Journal of the Korea Institute of Building Construction
• /
• v.14 no.6
• /
• pp.583-590
• /
• 2014

The purpose of this study is to analyze and compare the life cycle cost of window glass with insulation film and regular glass, to verify an economical window construction method. As an approach method, the thermal performance data of each type of glass was measured using Window 6.3 and ECO2-OD Simulation Program, applied it to the case building to calculate the air conditioning and heating maintenance costs and LCC, and compared the economic feasibility. As a result, installing an additional insulation film prevents the solar heat penetration in the summer, so it reduces the cooling cost, on the other hand, it increased heating cost in winter. From the life cycle cost perspective, the effect of cooling cost reduction does not counterbalance the increase in heating cost and the additional cost from film installation and repair; therefore, the installation of insulation film may not be a proper method.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.18 no.3
• /
• pp.436-445
• /
• 2012

Purpose: The purpose of this study was to identify social support networks for each life-cycle stage of adults. Method: A total of 1,047 subjects included 454 young adults, 262 middle-aged adults and 331 senior adults. Data were collected using Oh's Korean Version Norbeck's Social Support Questionnaire (NSSQ), and analyzed using descriptive statistics, t-test, and ANOVA. Result: For the young adults, parents were the top and second priority as important social support resources, the third was siblings, and then friends. For the middle-aged, spouse was the first priority as an important social support resource, while the second and the third were children. For the senior adults, children ranked from the top to the seventh priority. The mean number of social support resources was 13.23 for the young adult, 12.93 for the middle-aged and 5.30 for the senior adults. Social support networks of the young adults significantly differed according to gender and marital status. That of the middle-aged significantly differed according to family size. In addition, that of the senior adults was significantly different according to marital status, economic status, religion and family size. Conclusion: It is essential to consider social support networks for each life-cycle stage of adults when making a social support intervention program.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.56 no.5
• /
• pp.67-75
• /
• 2014

In this study, the large-scale hydraulic model test was performed to investigate the hydraulic characteristics for development of the non-power soil cleaning and keeping system at the dike gate. The outlet height, outflow number, outflow discharge, and outflow cycle were compared and analyzed. The non-power soil cleaning and keeping system was most effective at 11.2 mm in the outlet height. And then the mean outflow cycle was 1.09 sec, and the mean outflow discharge was $0.00164m^3/s$. The total outflow number increased gradually as the water level of a water tank increased, and the outlet height decreased. As a level of water tank decreased, the mean outflow cycle was lengthened, and the unit outflow discharge increased. This result showed this system was most effective. To remove the silty clay deposited in facilities, the methods of excavation, dredging, high pressure washing, etc have been applied to the tidal facilities such as land reclamation, a small size fishing port, and a harbor for maintenance. However, this is extremely cost-ineffective, whereas the non-power soil cleaning and keeping system will bring about an enormously positive economic effect. In addition, when the non-power soil cleaning and keeping system is applied to the dike gate of land reclamation, a thorough examination of the local tidal data and the careful system planning are required to prevent the disaster damage caused by flooding.

• Journal of the Korea Institute of Building Construction
• /
• v.16 no.2
• /
• pp.141-149
• /
• 2016

Recently, in an attempt to overcome the defects of quiescent power shutdown system, smart quiescent power control system has been developed. However, due to its higher investment costs, feasibility evaluation must be conducted. While LCCA (Life Cycle Cost Analysis) model is useful to estimate net savings of alternatives that differ with respect to initial costs and operating costs, the environmental burdens are not considered. On the contrary, LCA (Life Cycle Assessment) model is suitable to assess environmental impacts associated with the stages of a product's life but it does not consider costs. In this study, a comprehensive analysis on the economic and environmental impacts of smart quiescent power control system is conducted by using LCCA and LCA model. In addition, sensitivity analysis is carried out to quantify accuracy of estimates.

• Journal of Hydrogen and New Energy
• /
• v.32 no.3
• /
• pp.163-171
• /
• 2021

Securing energy sources is a key element essential to economic and industrial development in modern society, and research on renewable energy and hydrogen energy is now actively carried out. This research was conducted through experiments and analytical methods on the hydrogen filling process in the hydrogen storage tank of the hydrogen charging station. When low-temperature, high-pressure hydrogen was injected into a high-pressure tanks where hydrogen is charged, the theoretical method was used to analyze the changes in temperature and pressure inside the high-pressure tanks, the amount of hydrogen charge, and the charging time. The analysis was conducted in the initial vacuum state, called the First Cycle, and when the residual pressure was present inside the tanks, called the Second Cycle. As a result of the analysis, the highest temperature inside the tanks in the First Cycle of the high-pressure tank increased to 442.11 K, the temperature measured through the experiment was 441.77 K, the Second Cycle increased to 397.12 K, and the temperature measured through the experiment was 398 K. The results obtained through experimentation and analysis differ within ±1%. The results of this study will be useful for future hydrogen energy research and hydrogen charging station.

• Information Systems Review
• /
• v.10 no.1
• /
• pp.213-235
• /
• 2008

Recent reports about economic structure and changes show that global economy changes to rely on service rather than manufacturing. This phenomenon can be explained in two ways: the growth of service industry itself and the increasing reliance on service by other industry areas. The importance of service is indicated by the fact that the contribution of research and development, marketing, and finance to the revenue generation of companies is getting greater than that of manufacturing. This change in the economic structure calls for researchers' attention on the importance of service and the service-based economy. In the service-based economy, firms are considered value proposition providers and consumers actual value creators so that the concept of co-value creation becomes a key thesis to study. However, there are a variety of definitions of service and diversified measurements of service anchored in the supplier-oriented understanding of service yet. This lack of understanding of the service and the economic paradigm change causes a lot of problems in the areas of service productivity, service quality, and service innovation. Even though a new movement called service science started and rigorously pursues the way of enhancing the understanding of the economic change and service productivity, there is no framework that provides a unified view about the new role of service, service productivity, service quality, and thus service innovation. This study proposes a unified framework to provide a structured view about service provision and to facilitate the research on service. The framework is built on the concepts from previous studies about service marketing and service science: service life cycle and service networks including value activity network, resource integrator network, and capability network. We hope this study can be used as the basis for future studies on service science.