• International conference on construction engineering and project management
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• 2005.10a
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• pp.802-807
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• 2005

For linear projects, it has long been known that resource utilization is important in improving work efficiency. However, most existing scheduling techniques cannot satisfy the need for solving such issues. This paper presents an optimization model for solving linear scheduling problems involving resource assignment tasks. The proposed model adopts constraint programming (CP) as the searching algorithm for model formulation, and the proposed model is designed to optimize project total cost. Additionally, the concept of outsourcing resources is introduced here to improve project performance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.281-298
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• 2020

Fog computing has become a popular concept in the application of internet of things (IoT). With the superiority in better service providing, the edge cloud has become an attractive solution to IoT networks. The data outsourcing scheme of IoT devices demands privacy protection as well as computation verification since the lightweight devices not only outsource their data but also their computation. Existing solutions mainly deal with the operations over encrypted data, but cannot support the computation verification in the same time. In this paper, we propose a data outsourcing scheme based on an encrypted database system with linear computation as well as efficient query ability, and enhance the interlayer program in the original system with homomorphic message authenticators so that the system could perform computational verifying. The tools we use to construct our scheme have been proven secure and valid. With our scheme, the system could check if the cloud provides the correct service as the system asks. The experiment also shows that our scheme could be as effective as the original version, and the extra load in time is neglectable.

• Journal of Information Technology Services
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• v.16 no.2
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• pp.45-60
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• 2017

The study suggests a contract model of application operation through case study of A bank's IT outsourcing application contract based on workload. The IT outsourcing order form has a problem in that the scope of work is ambiguous due to the integration of operation and maintenance. In this study, application operation and maintenance were separated by referring to application operation history provided in ISO/IEC15504-5 standard. The scope of the IT outsourcing service was clarified by organizing the definition and detail activities of the application operation business. Application operation contract method has generally applied estimation method by the number of input manpower and period by agreement between buyer and client. As there is no activity to calculate the number of input manpower based on the operational work history and based on the standard workload per activity. In this case is not guaranteed due to the simple agreement between the contractors. In this paper, we propose an application operating cost estimation model that measures the size of the operating software using function point analysis that is the basis of application operation tasks. In order to verify the validity of the application operation cost model, we verified the correlation between the application size and the labor cost through regression analysis using SPSS.

• Journal of Distribution Science
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• v.20 no.6
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• pp.87-97
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• 2022

Purpose: In the last few decades, the ceramic industry has become an important industry for Indonesia. The resulting product must be handled properly, because if material & product handling is not carried out properly it will impact on the quality of product. Based on the logistics outsourcing research gaps in the ceramics industry to logistics service provider (LSP), this study aims to analyze the logistics service improvement of LSP in accordance with the needs of the ceramic industry to minimize logistics outsourcing risks. Research design, data and methodology: In the field study, observations, interviews and surveys related to production and logistics activities in the ceramic industry & LSP were carried out. The next step is to analyze logistics service of LSP needed by the ceramic industry. Results: The final findings obtained from this research are the LSP need to improve 1) knowledge; 2) technology capability; 3) relationships; 4) service quality; 5) innovation; 6) commitment in services. Conclusion: In order to reduce logistics outsourcing risks in the ceramic industry, LSP in Indonesia need to improve the logistics services required by the ceramic industry with a focus on six areas of improvement.

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

• Journal of Technology Innovation
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• v.17 no.1
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• pp.179-204
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• 2009

This paper aims to analyze the relationship between R&D outsourcing ratio (external R&D expenditures out of total R&D expenditures) and firm characteristics. Four hypotheses are tested using firm-level data with Tobit regression method. The major findings of this paper are as follows. First, firms with high technological capabilities, which are measured by R&D expenditures per sale and the number of patents per employee, rely more on R&D outsourcing. Nonetheless, firms that own R&D centers tend to rely less on external outsourcing of R&D. Second, firms with high managerial innovation capabilities, which is measured by the introduction of IT solutions, show higher R&D outsourcing ratio. Third, bigger firms are likely to spend more in external R&D than in internal R&D. This paper also discusses implications on R&D policy of Korea.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.5
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• pp.83-94
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• 2014

Before economical crisis in 1997, domestic company focused on increasing the size of outward experience which including organization. The result of increasing outward experience without substance was economical crisis, so after that time, many companies have been changing their focus from insourcing to strengthen the core competence to secure global market. This is becoming a cause of following that companies are reducing their outward experience. Especially, to process tasks more effectively and to cope with rapid change of business environment, such as incoming raw material from overseas/high raising of salary/rising property prices, many companies decided outsourcing method. At most of hypothesis, the result was that outsourcing can affect positively to the business. First, introducing of outsourcing during focusing on core competence can be positive effect for company performance such as business management /productivity /procurement /administration /product competitiveness /technology. Second, the result that analyzed based on a point of view of population statics after outsourcing was positive effect at the most of research. Third, result of effectiveness for every outsourcing type classified by 4M was also can be positive at the most of research. Fourth, the characteristic of population statics can be positive effect at the most of category when select outsourcing companies. Research result of outsourcing was various based on the goal of outsourcing. It is revealed by investigation of domestic/overseas treatise that there are opposite two opinions. In this research, there is no consistent result that the outsourcing can give effects on business performance, but most of hypothesis indicates that outsourcing can give positive effect on the business performance.In this research, based on the outsourcing intensity, mutual relation was analyzed. The assumption of the reason of outsourcing is economical and organizational. First, sampling numbers of research was too small so it is too difficult to get significant business performance result. (Sampling : 150, Replied : 106, Rate of Reply : 71%) Second, tried to compare significant differences of outsourcing methods which were divided based on 4M, but the there is gaps between the number of Cell and too difficult to make replier understand. Third, it is tried to find the degrees of effect that the point of view of popular statics can effect on business performances and selection of outsourced companies.

• Information Systems Review
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• v.22 no.4
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• pp.1-20
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• 2020

This study uses the bibliometric analysis and author bibliographic coupling analysis (ABCA) to analyse the study of IT outsourcing in Korea and China by 2017 and determine the subject areas of the researcher and the intellectual structure which lays the foundation for future researchers in IT outsourcing area. For this study, through the National Digital Science Library (NDSL) of Korea and China Academic Journal network publishing Database (CAJD) of China, it collected the connected documents and found out authors whose work had been published more than twice. ABCA is utilized to visualize the author map which could find out the researchers and areas in meaningful way. The result show that the study of IT outsourcing in Korea came out earlier and developed further than that of China. The study in Korea has already come to the mature period. By contrast, China remains at somewhere between developing period and bottleneck period. The distribution of papers are still in the dispersed state. The author map shows a hot subject area in Korean researchers IT outsourcing strategy is and in chinese scholars IT outsourcing management.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.8
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• pp.2708-2721
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• 2014

Data outsourcing in the cloud (DOC) is a promising solution for data management at the present time, but it could result in the disclosure of outsourced data to unauthorized users. Therefore, protecting the confidentiality of such data has become a very challenging issue. The conventional way to achieve data confidentiality is to encrypt the data via asymmetric or symmetric encryptions before outsourcing. However, this is computationally inefficient because encryption/decryption operations are time-consuming. In recent years, a few DOC schemes based on secret sharing have emerged due to their low computational complexity. However, Dautrich and Ravishankar pointed out that most of them are insecure against certain kinds of collusion attacks. In this paper, we proposed a novel DOC scheme based on Shamir's secret sharing to overcome the security issues of these schemes. Our scheme can allow an authorized data user to recover all data files in a specified subset at once rather than one file at a time as required by other schemes that are based on secret sharing. Our thorough analyses showed that our proposed scheme is secure and that its performance is satisfactory.

• Journal of Information Technology Applications and Management
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• v.14 no.1
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• pp.1-20
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• 2007

IT outsourcing becomes one of the important shills for managing diverse and complex information systems, SIA is considered as an one of the success factors for the successful outsourcing management. Since it helps to establish common goal and provides better visibility of trends and performance, the SLA process must go beyond mere measurement to include a methodology for the ongoing management of service levels, and for the continuous improvement of service activities, functions and processes. Despite SLA is one of the most important skills for the successful outsourcing, few studies have been conducted for academic as well as practical purpose. For this reason, The objective of this study is to develop an SLA's maturity model and empirically demonstrate how SLA's maturity level affects its Performance through SLA's maturity model. The major contributions of this study are in two areas. This study contributes to academicians as well as practitioners. First, from the academic perspectives this study tries investigating the maturity level of the SLA based on empirical data. Second, practitioners can self-test their firms' maturity level using the proposed model. The results of this study show that the SLA's maturity level affected positively SLA's performance. It is founded that the SLA's maturity level had a significant impact on SLA's performance.