• Journal of the Korean Society of Combustion
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• v.1 no.1
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• pp.1-10
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• 1996

An effective scale-up methodology of fluidized bed incinerators for low calorific value industrial wastes such as paper sludge and sewage sludge has been developed based on the similarity rules. Conventional scale-up theories are briefly reviewed and a new simple theory defining the diffusion Fourier number is established taking account of the lateral mixing of fuels in the fluidized bed. From the design and the operating conditions of the pilot FBC plant at Inchon, important design data for the full-scale incinerators are calculated and discussed.

• The Journal of Information Systems
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• v.29 no.1
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• pp.181-199
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• 2020

Purpose The purpose of this study is to analyze the current state of grounded theory methodology in Korea information systems studies and to suggest its application strategies. Design/methodology/approach After reviewing previous studies, this study reviewed 16 papers which adopted grounded theory methodology and analyzed these papers by two ways, research contents and methods adopted from grounded theory methodology: Main characteristics in grounded theory methodology are selected as main criteria in analysis such as data collection method, constant comparison, software use, coding ways, suggested model, proposition suggestion etc., while subject, theory/practice orientation, and role of prior knowledge are included in research contents. Findings Based on the review and analysis, this paper suggested four guidelines for adopting grounded theory methodology to information systems research in Korea: First, division of research methodology into stages. Second, explicit documentation of research process. Third, pursuit of diversity in research topics. Fourth, strengthening scale up and theoretical integration.

• Journal of Information Technology Services
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• v.20 no.5
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• pp.89-104
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• 2021

Food delivery service combined with IT technology and HMR (Home Meal Replacement) are rapidly growing due to the COVID-19. Recently, the demand for salads along with HMR has increased among office workers in their 20s and 30s who are interested in health and beauty. Freshcode is a food startup with 6 years of experience that started selling salad products through O2O service. Freshcode applied for a patent for a service that collects orders from nearby areas and delivers them on the same day to a designated delivery address 'FCOSPOT' to save shipping costs. In March 2021, in recognition of the growth potential of the regular delivery service, Freshcode received an investment of 6 billion won in Series A. This study may have practical implications to early-stage startups and scale-up stage startups through a longitudinal case study on the growth of a single company. As for the research method, the lean startup methodology and lean canvas were used in the early stage of startup. In particular, the process of the build-measure and learn feedback-loop, which is the core of lean startup methodology, was applied to each major decision-making step. In the scale-up stage after 5 years, the business model canvas was used to schematize the growth as a food online O2O platform to verify continuous innovation. This case study has three main findings. First, the idea of 'FCOSPOT' was successfully implemented through the Lean Startup methodology. Second, Freshcode demonstrated the scalability of the differentiated business model of shared base delivery O2O. Third, a key factor of success was the digital integrated communication operation strategy that maximizes the experience for the created customers.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1143-1152
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• 2012

We established a top-down methodology to estimate carbon footprint as national mean value (reference) with the statistical data on agri-livestock incomes in 2007. We also established LCI (life cycle inventory) DB by a bottom-up methodology with the data obtained from interview with farmers from 4 large-scale farms at Gunsan, Jeollabuk-do province to estimate carbon footprint in 2011. This study was carried out to compare top-down methodology and bottom-up methodology in performing LCA (life cycle assessment) to analyze the difference in GHGs (greenhouse gases) emission and carbon footprint under conventional rice cultivation system. Results of LCI analysis showed that most of $CO_2$ was emitted during fertilizer production and rice cultivation, whereas $CH_4$ and $N_2O$ were mostly emitted during rice cultivation. The carbon footprints on conventional rice production system were 2.39E+00 kg $CO_2$-eq. $kg^{-1}$ by top-down methodology, whereas 1.04E+00 kg $CO_2$-eq. $kg^{-1}$ by bottom-up methodology. The amount of agro-materials input during the entire rice cultivation for the two methodologies was similar. The amount of agro-materials input for the bottom-up methodology was sometimes greater than that for top-down methodology. While carbon footprint by the bottom-up methodology was smaller than that by the top-down methodology due to higher yield per cropping season by the bottom-up methodology. Under the conventional rice production system, fertilizer production showed the highest contribution to the environmental impacts on most categories except GWP (global warming potential) category. Rice cultivation was the highest contribution to the environmental impacts on GWP category under the conventional rice production system. The main factors of carbon footprints under the conventional rice production system were $CH_4$ emission from rice paddy field, the amount of fertilizer input and rice yield. Results of this study will be used for establishing baseline data for estimating carbon footprint from 'low carbon certification pilot project' as well as for developing farming methods of reducing $CO_2$ emission from rice paddy fields.

• Journal of Wellbeing Management and Applied Psychology
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• v.2 no.2
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• pp.39-45
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• 2019

The purpose of this study is to solve the problem of revision or abbreviation of questionnaires based on the previous studies suggested by many existing empirical studies. In addition, this study aims to provide the theoretical basis of the research method which has been variously approached since it presents the methodology that can directly measure the research object. For this purpose, this study proposed a more elaborate analysis method using the differences in perception of individuals who are interested in cognitive research. Specifically, the perception gap(D) can be used as an independent variable, a dependent variable, and a moderating variable. And this study suggested an effective research approach using the measurement of perception difference. The difference of perception suggested that it can be used as a measure to overcome the limitations of existing researches used it as independent variables or mediating variables that measure only one factor of expectation and performance or importance and satisfaction. In addition, it is highly likely that various analyzes on the perception differences, which are the result of measuring target factors for the same person, will be quite effective in the situation where follow-up of respondents is difficult. This study is expected to overcome various limitations reported by empirical studies such as scale utilization problem and follow-up survey difficulty. In future research, it was expected that the limitation of the factor derivation process in the research approach could be complemented by web crawling and text mining of big data analysis.

• Educational Technology International
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• v.10 no.1
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• pp.41-57
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• 2009

Cognitive presence, a sense of "being there" cognitively, has recently been considered as an important indicator for students' engagement in e-learning. There is, however, no widely accepted scale to measure the level of cognitive presence since most studies have put their effort to set and clarify the conceptual framework with qualitative methodology. This study reviewed existing theories on cognitive presence and related fields extensively and developed a new self-report scale for measuring the conceived level of cognitive presence. The reliability and validity of the scale was tested against 723 undergraduate students in two consecutive studies, 418 in the preliminary and 305 in the follow-up study. Three major constructs to measure the perceived level of cognitive presence were: 1) clear understanding, 2) knowledge construction, and 3) learning management. This paper reports the final results of the two independent studies.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.101-107
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• 2010

The aim of this paper is to come up with a methodology of constructing an efficient model for multiple representations which can manage and reconcile real-time data about large-scale roads in Vector Domain. In other words, we suggested framework based on a bottom-up approach, which is allowed to integrate data from the network of the lowest level sequentially and perform automated matching in order to produce variable-scale map. Finally, we applied designed multi-LoD model to in-vehicle application.

• IE interfaces
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• v.16 no.1
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• pp.70-84
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• 2003

Recently, object-oriented techniques have been used more and more for developments of an information system. But, established object-oriented methodologies are hard to express a business process of various abstract degrees in the analysis level and independent components of the system. They have difficulties in developing a large-scale information system of manufacturing industry such as PDM and CIM. This paper proposes an information system development methodology that imports the object-oriented IDEF0 (OOIDEF0) function model in analysis level. This methodology is made up of requirements gathering, system analysis, system design, and implementation. In requirements gathering level, organization diagram and interview technique are used for input data of OOIDEF0 function model. The OOIDEF0 function model, the interface model and function descriptions are made out in analysis level. Information objects and implementation objects are designed on the basis of the OOIDEF0 function model in design level. The database is built and programming is accomplished in implementation level. In order to prove the consistency and efficiency of the proposed methodology, the PDM system for ship production is modeled and prototyped.

• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.884-893
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• 2019

Spent fuel racks are steel structures used in the storage of the spent fuel removed from the nuclear power reactor. Rack units are submerged in the depths of the spent fuel pool to keep the fuel cool. Their free-standing design isolates their bases from the pool floor reducing structural stresses in case of seismic event. However, these singular features complicate their seismic analysis which involves a transient dynamic response with geometrical nonlinearities and fluid-structure interactions. An accurate estimation of the response is essential to achieve a safe pool layout and a reliable structural design. An analysis methodology based on the hydrodynamic mass concept and implicit integration algorithms was developed ad-hoc, but some dispersion of results still remains. In order to validate the analysis methodology, vibration tests are carried out on a reduced scale mock-up of a 2-rack system. The two rack mockups are submerged in free-standing conditions inside a rigid pool tank loaded with fake fuel assemblies and subjected to accelerations on a unidirectional shaking table. This article compares the experimental data with the numerical outputs of a finite element model built in ANSYS Mechanical. The in-phase motion of both units is highlighted and the water coupling effect is detailed. Results show a good agreement validating the methodology.

• Journal of Distribution Science
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• v.10 no.12
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• pp.19-24
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• 2012

Purpose - This paper discusses the heterogeneous fixed fleet vehicle routing problem with pick-up and delivery (HFFVRPPD), for vehicles with different capacities, fixed costs, and travel costs. Research Design, data, methodology - This paper made nine assumptions for establishing a mathematical model to describe HFFVRPPD. It established a practical mathematical model, and because of the non-deterministic polynomial-time hard (NP-hard), improved the traditional simulated annealing algorithm and tested a new algorithm using a certain scale model. Result - We calculated the minimum cost of the heterogeneous fixed fleet vehicle routing problem (HFFVRP) with a single task and, on comparing the results with the actual HFFVRP for the single task alone, observed that the total cost of HFFVRPPD reduced significantly by 46.7%. The results showed that the new algorithm provides better solutions and stability. Conclusions - This paper, by comparing the HFFVRP and HFFVRPPD results, highlights certain advantages of using HFFVRPPD in physical distribution enterprises, such as saving distribution vehicles, reducing logistics cost, and raising economic benefits.