• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.3
• /
• pp.193-200
• /
• 2022

In this study, the finite-failure NHPP software reliability model was applied to the software development model based on the Weibull lifetime distribution (Goel-Okumoto, Rayleigh, Type-2 Gumbe), which is widely used in the software reliability field, and then the cost attributes were compared and evaluated. For this study, failure time data detected during normal operation of the software system were collected and used, the most-likelihood estimation (MLE) method was applied to the parameter estimation of the proposed model, and the calculation of the nonlinear equation was solved using the binary method. As a result, first, in the software development model, when the cost of testing per unit time and the cost of removing a single defect increased, the cost increased but the release time did not change, and when the cost of repairing failures detected during normal system operation increased, the cost increased and the release time was also delayed. Second, as a result of comprehensive comparative analysis of the proposed models, it was found that the Type-2 Gumble model was the most efficient model because the development cost was lower and the release time point was relatively faster than the Rayleigh model and the Goel-Okumoto basic model. Third, through this study, the development cost properties of the Weibull distribution model were newly evaluated, and the analyzed data is expected to be utilized as design data that enables software developers to explore the attributes of development cost and release time.

• Journal of Korean Institute of Industrial Engineers
• /
• v.27 no.3
• /
• pp.297-304
• /
• 2001

Procurement decisions for inspection equipment are often made heavily based on the initial purchase price instead of the effects of inspection cost, equipment calibration and utilization over the lifetime. Cost of ownership(COO) models that take into account all of these cost factors together have been developed focusing on a single quality characteristic. In modern manufacturing environment, inspection equipment often can deal with more than one quality characteristic simultaneously. In this paper, we propose the revised COO model for the economic evaluation of the inspection equipment that can accommodate multiple quality characteristics. We also employ an engineering economy model to compare equipments with different life span. Software is developed for handy comparison of the COO of alternative equipments along with sensitivity analysis far the optimal procurement decision.

• Journal of Korean Society of Steel Construction
• /
• v.23 no.5
• /
• pp.557-568
• /
• 2011

To effectively come up with and secure a national budget, it is very important to estimate the reasonable construction cost of each step in public construction projects. In this study, the approximate construction cost of a steel box girder bridge in the early stages of the project, on which available information is limited, was proposed using case-based reasoning. In addition, construction cost estimation models were used for existing sample design models, and the accuracy of the estimation model for the presented cost was verified. The analysis results showed that the error rate was comparatively stable. Therefore, it is expected that construction cost estimation will be effectively suggested in the country's budget preparation.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.7
• /
• pp.149-158
• /
• 2020

The purpose of this study was to investigate the impact of corporate governance index on the cost of equity in companies listed on the Tehran Stock Exchange. This study collects data from 975 observations during the period 2012 to 2018 to test the hypotheses using multiple linear regression model for the panel data. In this research, the independent variable of corporate governance index comprises of 27 specific corporate governance attributes. The results of hypothesis testing showed that corporate governance has a negative and significant effect on the rate of capital cost. In other words, the quality of corporate governance can lower the rate of capital cost. This result suggests that, by using a powerful corporate governance system and by declining the information asymmetry (increasing transparency) and agency conflict, we would be able to enhance the quality of financial reports. It would strengthen the capital market, attract financial suppliers and investors, and absorb the required financial resources of the firm by a lower rate. The findings of the study suggest that companies are able to reduce the cost of equity by establishing strong corporate governance. This conclusion suggests the importance and effectiveness of corporate governance in the cost of equity.

• Journal of the Korea Institute of Building Construction
• /
• v.21 no.2
• /
• pp.105-112
• /
• 2021

While the scale of the domestic market for demolition work is steadily increasing, research on cost prediction for demolition work is insufficient. Thus, this study proposes a cost prediction model for demolition work that reflects various attributes influecing the fluctuation of demolition cost. 13 influencing factors and historical cost data were collected based on literature review and experts' advice, and two prediction models were constructed through regression analysis and the prediction accuracy was evaluated. As a result, it showed an average error rate of about 6 to 12%, and it was possible to explore the possibility of use as a reliable prediction model. The results of this study can contribute to estimating appropriate construction cost and improving related standards for domestic demolition works in the future.

• The Journal of the Korea Contents Association
• /
• v.9 no.12
• /
• pp.235-244
• /
• 2009

The object of this research is to analyze the impact of the four dimensions of on-line game attributes, challenge, social interaction, entertainment and actuality, on customer satisfaction and loyalty. At the same time, mediating effects of switching barriers, such as switching cost and attractiveness of alternatives on the relationships between customer satisfaction and customer loyalty are also analyzed. The results showed that the challenge, social interaction, entertainment had significant effects on customer satisfaction. Customer satisfaction also effected customer loyalty. Another important result is that switching cost and attractiveness of alternatives played an intermediating role between customer satisfaction and customer loyalty.

• Proceedings of the Korea Contents Association Conference
• /
• 2009.05a
• /
• pp.341-347
• /
• 2009

In this research, the object is to analysis the impact of the four dimensions of on-line game attributes, challenge, social interaction, entertainment and actuality, on customer satisfaction and loyalty. At the same time as mediating factors of relationship between customer satisfaction and customer loyalty, switching barriers, such as switching cost and attractiveness of alternatives are also analyzed. The results show that the challenge, social interaction, entertainment have significant effect on customer satisfaction. Customer satisfaction also effects customer loyalty. Another important result is, switching cost and attractiveness of alternatives take an intermediation role between customer satisfaction and customer loyalty.

• Journal of the Korea Society of Computer and Information
• /
• v.24 no.3
• /
• pp.191-199
• /
• 2019

This study is about online purchases of foods that have been reluctant to deal with distribution processes and reliability issues. We find out that attributes of the online food market affects behavior intention and whether it differs according to consumption tendency. A survey was conducted on consumers who had ever purchased food online for hypothesis testing. Reliability and feasibility were reviewed for the collected data and the hypothesis was verified through structural equation model analysis. While product diversity, product information and customer service factors of the online food market significantly affect behavior intention, price is not. We identified differences in the impact of behavior intention on consumption tendencies. For the Gaseongbi group, only the product information factors have significant effect on behavior, and for the Gasimbi group, the price and customer service factors have a significant effect on behavior intention. The findings provide theoretical and practical implications for marketers to study various marketing method based on consumer tendencies.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.43 no.4
• /
• pp.33-40
• /
• 2020

In order to satisfy customers, it is important to identify the quality elements that affect customers' satisfaction. The Kano model has been widely used in identifying multi-dimensional quality attributes in this purpose. However, the model suffers from various shortcomings and limitations, especially those related to survey practices such as the data amount, reply attitude and cost. In this research, a model based on the text sentiment analysis is proposed, which aims to substitute the survey-based data gathering process of Kano models with sentiment analysis. In this model, from the set of opinion text, quality elements for the research are extracted using the morpheme analysis. The opinions' polarity attributes are evaluated using text sentiment analysis, and those polarity text items are transformed into equivalent Kano survey questions. Replies for the transformed survey questions are generated based on the total score of the original data. Then, the question-reply set is analyzed using both the original Kano evaluation method and the satisfaction index method. The proposed research model has been tested using a large amount of data of public IT service project evaluations. The result shows that it can replace the existing practice and it promises advantages in terms of quality and cost of data gathering. The authors hope that the proposed model of this research may serve as a new quality analysis model for a wide range of areas.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.7
• /
• pp.1935-1950
• /
• 2023

The arrival of the Internet of Things and 5G technology enables users to rely on edge computing platforms to process massive data. Data sharing based on edge computing refines the efficiency of data collection and analysis, saves the communication cost of data transmission back and forth, but also causes the privacy leakage of a lot of user data. Based on attribute-based encryption and blockchain technology, we design a fine-grained access control scheme for data in edge computing, which has the characteristics of verifiability, support for outsourcing decryption and user attribute revocation. User attributes are authorized by multi-attribute authorization, and the calculation of outsourcing decryption in attribute encryption is completed by edge server, which reduces the computing cost of end users. Meanwhile, We implemented the user's attribute revocation process through the dual encryption process of attribute authority and blockchain. Compared with other schemes, our scheme can manage users' attributes more flexibly. Blockchain technology also ensures the verifiability in the process of outsourcing decryption, which reduces the space occupied by ciphertext compared with other schemes. Meanwhile, the user attribute revocation scheme realizes the dynamic management of user attribute and protects the privacy of user attribute.