• International Journal of Fluid Machinery and Systems
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• v.3 no.4
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• pp.352-359
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• 2010

In recent years, the market has shown increasing interest in pump-turbines. The prompt availability of pumped storage plants and the benefits to the power system achieved by peak lopping, providing reserve capacity, and rapid response in frequency control are providing a growing advantage. In this context, there is a need to develop pumpturbines that can reliably withstand dynamic operation modes, fast changes of discharge rate by adjusting the variable diffuser vanes, as well as fast changes from pumping to turbine operation. In the first part of the present study, various flow patterns linked to operation of a pump-turbine system are discussed. In this context, pump and turbine modes are presented separately and different load cases are shown in each operating mode. In order to create modern, competitive pump-turbine designs, this study further explains what design challenges should be considered in defining the geometry of a pump-turbine impeller. The second part of the paper describes an innovative, staggered approach to impeller development, applied to a low head pump-turbine project. The first level of the process consists of optimization strategies based on evolutionary algorithms together with 3D in-viscid flow analysis. In the next stage, the hydraulic behavior of both pump mode and turbine mode is evaluated by solving the full 3D Navier-Stokes equations in combination with a robust turbulence model. Finally, the progress in hydraulic design is demonstrated by model test results that show a significant improvement in hydraulic performance compared to an existing reference design.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.1
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• pp.171-178
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• 2016

In engineering industry, technical documentation refers to any type of documentation that describes handling, functionality and architecture of a technical product. The intended audiences for product technical documentation is the end user, the administrator, service or maintenance technician. Competition and rapid technological evolutions have created pressure to release new and improved products on an increasingly frequent basis. As the technical capabilities of products advance, the technical documentation for those products is becoming longer and complex. The Darwin Information Typing Architecture (DITA) is and XML-based, end-to-end architecture for authoring, producing, and delivering technical documents. DITA is an OASIS standard that allows documentation groups to single-source document for multiple products and users, to automatically publish that documentation in several media formats including PDF and HTML, and to efficiently maintain and update that documentation. This paper study on the various implementation projects for technical documentation using OASIS DITA standard and examines the potential for using DITA as a solution for reconstructing existing technical documentation. Also We offer an incremental adoption approach to effectively implement DITA standard of technical documentation project for domestic firms, while reducing failures.

• Journal of Information Technology Services
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• v.7 no.3
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• pp.97-114
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• 2008

Many companies have implemented ERP systems to enhance their process competitiveness. Since most ERP systems down to date are implemented and managed on each separated business-unit or company level, such systems run short of the consideration about global business processes and global system managements. In order to integrate a successful global ERP, it is essential to apply the well-systematic implementation methodology which considers global standardization and global IT requirements. It is, however, the actual circumstance that such well-structured methodologies for global ERP implementation are hardly shown not only from domestic site but from foreign one. This paper indicates the global ERP implementation guideline with integrated approach including; the standard process design for efficient execution of global business; the ERP implementation method considering global IT requirements; and, the management method for global system operation. GSI ERP methodology is composed of 3 Phase：Global Strategy Planning, Global Template Construction and Global Roll-Out. Phase1; Global Strategy Planning contains Environment Analysis, GSI direction and Implementation Plan. Phase2; Global Template Construction contains Business blueprint, GSI operation design and Global template implementation. Phase3; Global Roll-out contains local business analysis, local ERP implementation and Global ERP Operation.

• Asia-Pacific Journal of Business
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• v.12 no.1
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• pp.165-182
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• 2021

Purpose - The purpose of this study is to compare and analyze the ordinances of other local governments to propose implications and improvement plans for the ordinances of Chuncheon City. To this end, cases of overseas legislation related to youth labor rights, domestic laws and major policies of the central government were reviewed. Design/methodology/approach - This study mainly utilized literature research methods. In addition, it was based on foreign laws and case analysis, domestic laws and ordinances, and preceding research and data related to government policies. Findings - Chuncheon city ordinances are superior to those of other local governments. However, the details of the establishment of the implementation plan, the actual condition survey, and the establishment of the consultation system are included in the project contents of Article 6, so it is not concrete and clear. And there were no articles related to the labor environment check. Research implications or Originality - It is proposed to make the contents of the establishment of an implementation plan, survey, and consultation system as independent provisions. It is also proposed to establish a new article related to the youth labor environment check. In addition, it is desirable to establish detailed regulations by establishing the ordinance enforcement regulations.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_2
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• pp.715-724
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• 2023

Solar energy forecasting is essential for (1) power system planning, management, and operation, requiring accurate predictions. It is crucial for (2) ensuring a continuous and sustainable power supply to customers and (3) optimizing the operation and control of renewable energy systems and the electricity market. Recently, research has been focusing on developing solar energy forecasting models that can provide daily plans for power usage and production and be verified in the electricity market. In these prediction models, various data, including solar energy generation and climate data, are chosen to be utilized in the forecasting process. The most commonly used climate data (such as temperature, relative humidity, precipitation, solar radiation, and wind speed) significantly influence the fluctuations in solar energy generation based on weather conditions. Therefore, this paper proposes a hybrid forecasting model by combining the strengths of the Prophet model and the GRU model, which exhibits excellent predictive performance. The forecasting periods for solar energy generation are tested in short-term (2 days, 7 days) and medium-term (15 days, 30 days) scenarios. The experimental results demonstrate that the proposed approach outperforms the conventional Prophet model by more than twice in terms of Root Mean Square Error (RMSE) and surpasses the modified GRU model by more than 1.5 times, showcasing superior performance.

• Journal of Nuclear Fuel Cycle and Waste Technology
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• v.1 no.1
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• pp.9-27
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• 2013

Nagra was established in 1972 by the Swiss nuclear power plant operators and the Federal Government to implement permanent and safe disposal of all types of radioactive waste generated in Switzerland. The Swiss Nuclear Energy Act specifies that these shall be disposed of in deep geological repositories. A number of different geological formations and sites have been investigated to date and an extended database of geological characteristics as well as data and state-of-the-art methodologies required for the evaluation of the long-term safety of repository systems have been developed. The research, development, and demonstration activities are further supported by the two underground research facilities operating in Switzerland, the Grimsel Test Site and the Mont Terri Project, along with very active collaboration of Nagra with national and international partners. A new site selection process was approved by the Federal Government in 2008 and is ongoing. This process is driven by the long-term safety and feasibility of the geological repositories and is based on a step-wise decision-making approach with a strong participatory component from the affected communities and regions. In this paper a brief history and the current status of the Swiss radioactive waste management program are presented and special characteristics that may be useful beyond the Swiss program are highlighted and discussed.

• Ocean Systems Engineering
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• v.9 no.2
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• pp.191-218
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• 2019

The tower-platform interface and mooring system of floating offshore wind turbines (FOWTs) are some of the most critical components with significant influences on overall project costs. In addition to satisfying strength requirements, it is typical and vital to meet fatigue criteria for a service life of 25 years or more. Wind spectra characteristics considered in analysis can penalize fatigue designs, leading to unnecessary costs. The International Electrotechnical Commission (IEC, 2009) recommends the use of site-specific wind data (spectrum, turbulence intensity, etc.) in design of FOWTs, but for offshore sites it is often the case that such data is unavailable and land-based data are used as surrogates in design. For such scenarios, it is worth investigating whether such alternative approach is suitable and accurate, and understanding the consequence of the selection of wind spectral characteristics on fatigue design. This paper addresses the impact of the subsequent selection on fatigue responses of towerbase and mooring system in a FOWT, as a sequel to the paper by Udoh and Zou (2018) which focused on impacts on strength design. The 5 MW semi-submersible FOWT platform with six mooring lines implemented in the preceding study is applied in analysis. Results indicate significant variations in resulting fatigue life with considered wind parameters. Thus, it is critical to apply proper wind spectra characteristics for analysis and design of FOWTs to avoid unnecessary conservatism and costs. Based on the findings of this study, more explicit guidance on the application of turbulence intensities for IEC-recommended models in offshore sites could lead to more accurate load estimates in design of FOWTs.

• SUVANNABHUMI
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• v.12 no.2
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• pp.157-200
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• 2020

This paper explores critically and historically some of the popular academic views concerning the development of the study of Southeast Asia through the lens of the contributions of particular scholars and institutions. Within the broad field of Southeast Asian Studies the focus is on the disciplines of geography, history and ethnology. There are certain views concerning the development of scholarship on Southeast Asia which continue to surface and have acquired, or are in the process of acquiring "mythical" status. Among the most enduring is the claim that the region is a post-Second World War construction primarily arising from Western politico-strategic and economic preoccupations. More specifically, it is said that Southeast Asian Studies for a considerable period of time has been subject to the American domination of this field of scholarship, located in programs of study in such institutions as Cornell, Yale and California, Berkeley, and, within those institutions, focused on particular scholars who have exerted considerable influence on the directions which research has taken. Another is that, based on the model or template of Southeast Asian Studies (and other area studies projects) developed primarily in the USA, it has distinctive characteristics as a scholarly enterprise in that it is multidisciplinary, requires command of the vernacular, and assigns special importance to what has been termed 'groundedness' and historical, geographical and cultural contextualization; in other words, a Southeast Asian Studies approach as distinct from disciplinarybased studies addresses local concerns, interests, perspectives and priorities through in-depth, on-the-ground, engaged scholarship. Finally, views have emerged that argue that a truly Southeast Asian Studies project can only be achieved if it is based on a set of locally-generated concepts, methods and approaches to replace Western ethnocentrism and intellectual hegemony.

• The KIPS Transactions:PartD
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• v.8D no.2
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• pp.154-165
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• 2001

A number of attempts to develop methods for measuring software effort have been focused on the area of software engineering and many models have also been suggested to estimate the effort of software projects. Almost all current models use algorithmic or statistical mechanisms, but the existing algorithmic effort estimation models have failed to produce accurate estimates. Furthermore, they are unable to reflect the rapidly changing technical environment of software development such as module reuse, 4GL, CASE tool, etc. In addition, these models do not consider the paradigm shift of software engineering and information systems(i.e., Object Oriented system, Client-Server architecture, Internet/Intranet based system etc.). Thus, a new approach to software effort estimation is needed. After reviewing and analyzing the problems of the current estimation models, we have developed a model and a system architecture that will improve estimation performance. In this paper, we have adopted a neural network model to overcome some drawbacks and to increase estimation performance. We will also address the efficient system architecture and estimation procedure by a similar case-based approach and finally suggest the heuristic search method to find the best estimate of target project through empirical experiments. According to our experiment with the optimally parsimonious neural network model the mean error rate was significantly reduced to 14.3%.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.7
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• pp.109-117
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• 2010

Building a large-scale testbed for Future Internet is very important to evaluate a new protocol and new network architecture designed by clean-slate approach. In Korea, new Future Internet testbed project, called FIRST (Future Internet Research for Sustainable Testbed), has been started since Mar. 2009 to design and test new protocols. This project is working together with ETRI and 5 universities. The FIRST@PC is to implement a virtualized hardware-accelerated PC-node by extending the functions of NetFPGA card and build a Future Internet testbed on the KOREN and KREONET for evaluating newly designed protocols and interesting applications. In this paper, we first briefly introduce FIRST@PC project and explain a 'MAC in IP Capsulator' user-space program using raw-socket in Linux to interconnect OpenFlow enabled switch sites on the KOREN and KREONET. After that, we address test results for TCP throughput performance for varying packet size. The test results show that the software based capsulator can support a reasonable bandwidth performance for most of applications.