• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.3
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• pp.114-121
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• 2004

Switched reluctance motors have received much attention as a driving means for various industrial applications because they have simple construction, low cost and high efficiency. Nevertheless, the requirements of drive converters make it difficult to lower the overall system cost as compared with the DC motor application. Single phase switched reluctance motors (SPSRMs) provide a solution to the high cost problem since the number of switching power devices can be reduced and consequently the trials for application are increased. However, research involving SPSRMs, especially in the area of design work, is insufficient. This paper introduces a novel design methodology of single phase SRM. The design work for SPSRM comprises the determination of many variables such as stator and rotor pole arc as well as on, off and so on. Managing all variable combinations leads to lengthy computation time and a fault in the design process. For that reason, a reliable technique and brief procedure term are required in SPSRM design.

• The Transactions of the Korea Information Processing Society
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• v.7 no.3
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• pp.745-755
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• 2000

In designing distributed databases, DAP(Data Allocation Problem) is one of the key design issues. Because, however, most of previous researches on DAP have considered only cost aspect, they cannot increase the performance and availability and they are not proper to the system requiring high-availability or real-time processing. Therefore, we need a more formal data allocation model considering multiple aspects. In this paper, we propose the MAPN (Multiple Aspects Petri Net) modeling method for the distributed transaction modeling. The MAPN model, an extended classical petri net, is proposed for the formal modeling considering multiple aspects (cost, performance and availability) concurrently. We demonstrate that we can compose the valid DAP evaluation model considering not only cost but also performance and availability concurrently by using the MAPN structure and MAPN graph.

• Journal of KIISE:Databases
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• v.30 no.1
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• pp.64-79
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• 2003

In client-server computing environments, update transactions of spatial data have the following characteristics. First, a transaction to update maps needs interactive work, and therefore it nay take a long time to finish. Second, a long transaction should be allowed to read the dirty data to enhance parallelism of executing concurrent transactions. when %he transaction is rolled back, it should guarantee the cascading rollback of all of the dependent transactions. Finally, two spatial objects may have a weak dependency constraint, called the spatial relationship, based on geometric topology. The existing recovery approaches cannot be directly applied to this environment, due to the high rollback cost and the overhead of cascading rollbacks. Furthermore, the previous approaches cannot guarantee the data integrity because the spatial relationship, which is a new consistency constraint of spatial data, is not considered. This paper presents new recovery schemes for update transactions of spatial data. To guarantee the data integrity, this paper defines recovery dependency as a rendition of cascading rollbacks. The partial-rollback is alto suggested to solve the problem of high rollback cost. The recovery schemes proposed in this paper can remove the unnecessary cascading rollbacks by using undo-delta, partial -redo and partial-undo. Finally, the schemes are performed to ensure the correctness.

• The Journal of Society for e-Business Studies
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• v.23 no.1
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• pp.1-22
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• 2018

The value chain has been utilized as a strategic tool to improve competitive advantage, mainly at the enterprise level and at the industrial level. However, in order to conduct value chain analysis at the enterprise level, the client companies of the parent company should be classified according to whether they belong to it's value chain. The establishment of a value chain for a single company can be performed smoothly by experts, but it takes a lot of cost and time to build one which consists of multiple companies. Thus, this study proposes a model that automatically classifies the companies that form a value chain based on actual transaction data. A total of 19 transaction attribute variables were extracted from the transaction data and processed into the form of input data for machine learning method. The proposed model was constructed using the Random Forest algorithm. The experiment was conducted on a automobile parts company. The experimental results demonstrate that the proposed model can classify the client companies of the parent company automatically with 92% of accuracy, 76% of F1-score and 94% of AUC. Also, the empirical study confirm that a few transaction attributes such as transaction concentration, transaction amount and total sales per customer are the main characteristics representing the companies that form a value chain.

• Information Systems Review
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• v.18 no.1
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• pp.177-197
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• 2016

Information technology (IT) outsourcing is considered an effective strategy to manage and maintain organizational technologies in a rapidly changing business environment. In particular, to meet diverse market needs, many organizations that outsource their IT functions practice a multi-vendor approach as their main outsourcing strategy. Although a few studies have been conducted about the multi-vendor approach, most previous works primarily emphasized conceptual arguments and normative prescriptions. In addition, scant attention has been directed toward the relational structure between the client and multiple vendors in the multi-vendor approach and its implications for outsourcing success. This study proposes a model from the transaction cost perspective by conceptualizing two dominant relational structures of the multi-vendor approach, namely, single-vendor dominant model and the multi-vendor dominant model, and hypothesizing their relationships with two outsourcing outcomes, project success and user satisfaction. The proposed model is examined using the data collected from 246 companies that have implemented multi-vendor outsourcing. As expected, results indicate that the single-vendor dominant model has a more significant impact on project success, whereas the multi-vendor dominant model has a more significant impact on user satisfaction. The study concludes with the theoretical implications and directions for future research.

• Journal of Korean Institute of Industrial Engineers
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• v.4 no.2
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• pp.67-75
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• 1978

This paper attempts to identify the factors which are directly related to the effective transfer of technology from developed countries to LDCs. The recipient countries should have the capability of alteration/adaptation based on cost-minimization criteria. Some problems are such that technologies are transferred on the conditions of MNFs, packaged forms and under state management which result in lack of competitive pressure. Non-technological criteria are shown to be a problem under state management in the transaction of technology.

• Journal of Distribution Research
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• v.1 no.1
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• pp.147-196
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• 1996

The objective of this study is th analyse the determinant factors of the marketing channel structures in the five industries, including homo-electronics, automobile, oil, liquors, and fast-food industries, on the basis of the transaction cost TCA and to develop the complementary and exensive conceptuai model for understanding the determinants of the channel structures. TCA is relatively weak and besides of the TCA varkables other environmental or relational variables are more likely to dorminate the channel structuring.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.768-773
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• 2005

Among various joint ventures, International Construction Joint Ventures (ICJVs) have emerged as a popular approach worldwide to developing large scale projects through international participation. A model, based on economic analysis and represented by several hypotheses obtained from the analysis, will be developed. Furthermore, we will empirically test the hypotheses/model using Structural Equation Model (SEM). This research is expected to explain why there exist different organizational forms for ICJVs, and to develop a framework for choosing appropriate forms with respect to various characteristics of ICJVs.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.3
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• pp.139-144
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• 2016

When, Software is developed, Applying development methods considering security, it is generated the problem of additional cost. These additional costs are caused not consider security in many developing organization. Even though, proceeding the developments, considering security, lack of ways to get the cost of handling the vulnerability throughput within the given cost. In this paper, propose a method for calculating the vulnerability throughput for using a security vulnerability processed cost-effectively. In the proposed method focuses on the implementation phase of the software development phase, leveraging static analysis tools to find security vulnerabilities in CWE TOP25. The found vulnerabilities are define risk, transaction costs, risk costs and defines the processing priority. utilizing the information in the CWE, Calculating a consumed cost in a detected vulnerability processed through a defined priority, and controls the vulnerability throughput in the input cost. When applying the method, it is expected to handle the maximum risk of vulnerability in the input cost.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.4
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• pp.185-192
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• 2001

In SRM drive, the ON·OFF angles of each phase switch should be accurately controlled in order to control the torque and speed stably. The accuracy of the switching angles is dependent upon the resolution of the encoder and the sampling period of the microprocessor, that are used to provide the information of the rotor position and to control the SRM power circuit, respectively. However, as the speed increases, the amount of the switching angle deviation from the preset values is also increased. Therefore, the low cost encoder suitable for the practical and stable SRM drive is proposed and the control algorithm to provide the switching signals using the simple digital logic circuit is also presented in this paper, As a result, a stable high speed SRM drive can be achieved by the high resolution switching angle control and it is verified from the experiments that the proposed encoder the logic controller can be a powerful candidate for the practical low cost SRM drive.