• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.11
• /
• pp.3003-3029
• /
• 2023

The rapid evolution of the IoT has paved the way for new opportunities in smart city domains, including e-health, smart homes, and precision agriculture. However, this proliferation of services demands effective SLAs between customers and service providers, especially for critical services. Difficulties arise in maintaining the integrity of such agreements, especially in vulnerable wireless environments. This study proposes a novel SLA management model that uses an SDN-Enabled WSN consisting of wireless nodes to interact with smart contracts in a straightforward manner. The proposed model ensures the persistence of network metrics and SLA provisions through smart contracts, eliminating the need for intermediaries to audit payment and compensation procedures. The reliability and verifiability of the data prevents doubts from the contracting parties. To meet the high-performance requirements of the blockchain in the proposed model, low-cost algorithms have been developed for implementing blockchain technology in wireless sensor networks with low-energy and low-capacity nodes. Furthermore, a cryptographic signature control code is generated by wireless nodes using the in-memory private key and the dynamic random key from the smart contract at runtime to prevent tampering with data transmitted over the network. This control code enables the verification of end-to-end data signatures. The efficient generation of dynamic keys at runtime is ensured by the flexible and high-performance infrastructure of the SDN architecture.

• Korea Trade Review
• /
• v.43 no.4
• /
• pp.27-50
• /
• 2018

This study focuses on the judgement of Seoul High Court' regarding the formation and performance of contracts applying the CISG. The purpose of this study is to provide legal understanding to contracting parties involved in contract for the international sale of goods that can be considered in raising the understanding of the CISG within the scope of the subject. This study aimed at the legal validity of judgments, the defects in reason for judgments and legal standards that could be established. The main contribution of this study is summarizing the facts of judgments and arguments of the parties and furthermore, in accordance with the order, the judgment order of the court and the decision criteria of the application law, the CISG articles comment and interpretation on the formation of the contract, legal bases of fundamental breach of contract, termination of contract, concurrent fulfillment and other supplementary matters and so on.

• International conference on construction engineering and project management
• /
• 2020.12a
• /
• pp.343-352
• /
• 2020

Modular integrated construction (MiC) is an innovative construction method where components of a building are manufactured in an offsite factory, trucked to the job site in sections, set in place with cranes, and assembled together to form a whole building. Where circumstances merit, favorable conditions exist and implemented effectively; MiC improves project performance. However, several key factors need to converge during implementation to realize the full benefits of MiC. Thus, a thorough understanding of the factors which are critical to the success of MiC projects is imperative. Drawing on a systematic review of 47 empirical studies, this research identified 25 key success factors (KSFs) for MiC projects. Of these, the five topmost cited KSFs for MiC projects include effective working collaboration and communication among project participants; standardization, optimization, automation and benchmarking of best practices; effective supply chain management; early design freeze and completion; and efficient procurement method and contracting. The study further proposed a conceptual model of the KSFs, highlighting the interdependences of people, processes, and technology-related KSFs for the effective accomplishment of MiC projects. The set of KSFs is practically relevant as they constitute a checklist of items for management to address and deal with during the planning and execution of MiC projects. They also provide a useful basis for future empirical studies tailored towards measuring the performance and success of MiC projects. MiC project participants and stakeholders will find this research useful in reducing failure risks and achieving more desired performance outcomes. One potential impact of the study is that it may inform, guide, and improve the successful implementation of MiC projects in the construction industry. However, the rigor of the analysis and relative importance ranking of the KSFs were limited due to the absence of data.

• Journal of Distribution Science
• /
• v.12 no.2
• /
• pp.39-47
• /
• 2014

Purpose - The ultimate goal of a franchise system comes from its win-win strategy. Agency theory uses goal incongruity to examine complex contracting problems between buyers and suppliers. Goal incongruity within a contractual relationship can be defined as the agent's desire not to cooperate. It is the degree to which the contractual terms do not satisfy the agent's goals. The greater the goal incongruity between the agent and the contract, the more likely it is that the agent will meet the terms of the contract. Thus, goal incongruity between buyers and suppliers has close relationships with both behavioral and financial performance. This study tries to examine these relationships in the franchise context using a model including related variables, such as regulatory foci, financial performance, and opportunism, to explain the reasons that not all franchisees perform their best. In particular, the study examines the effects of goal incongruity on regulatory focus, and the effects of regulatory focus on performance and opportunism. In short, the objective is to determine goal incongruity's effect on regulatory foci, and the effect of regulatory focus on performance and opportunism. Research design, data, and methodology - This study used data collected from the franchisee managers of 104 franchisors in South Korea. The franchisors include more than 10 franchisees, the majority of whom have been in business for more than five years. The study also surveyed 104 franchisees, matched with their franchisors for the sake of a dyadic approach. The study used regression analysis to test the hypotheses. Results - H1 and H2 predicted that goal incongruity would decrease promotion focus and increase prevention focus. Supporting H1, the result indicates goal incongruity had a positive effect on promotion focus. However, H2 was not supported. Goal incongruity had no significant effect on prevention focus (β = -.375, t = -4.331 and β = -.145, t = -1.950, respectively). H3 and H4 predicted that promotion focus would increase financial performance and decrease opportunism. Supporting these hypotheses, the results indicate that promotion focus had a positive effect on financial performance and a negative effect on opportunism (β = .771, t = 7.899 and β = -.765, t = -6.778, respectively). H5 and H6 predicted that prevention focus would decrease financial performance and increase opportunism. However, the results do not support these hypotheses. The results indicate that prevention focus had no effects on opportunism or financial performance (β = -.130, t = -1.070 and β = .090, t = .641, respectively). Overall, the evidence generally supported the hypotheses. Conclusion - Goal incongruity between a franchisor and a franchisee increases the franchisee's financial performance and opportunism, and the relationship is mediated by promotion focus. Interestingly, however, prevention focus has no mediating effect between goal incongruity and performance. Even though no significant relation exists between goal incongruity and prevention focus, the results have two implications. First, decreasing goal incongruity can improve financial performance and suppress franchisee opportunism. Second, the relationship between goal incongruity and performance affects promotion-focused franchisees.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.32
• /
• pp.3-27
• /
• 2006

The Pennzoil case and the SME case illustrate the difficulties which originate from inadequate drafting of letters of intent. In both cases the judges had to face the crucial question as to whether or not a given letter of intent had a binding nature; they had in other words to decide whether the wills expressed in such letters still belonged to the pre-contractual stage, or whether their incorporation into a pre-contractual document meant that negotiations were over and binding obligations had already arisen for the parties. In other words, some problems may occur when a party has documented a stage in the negotiations by letters of intent. The letters may well explicitly spell out if, and to what extent, the parties should be bound by what they have already agreed or to carry on negotiations in order to reach the final contract. But if the letters are silent, some problems would arise. Contracting parties are, therefore, well advised to spell out if, and to what extent, they should be bound by such preliminary agreements. Here again, it might be prudent to explicitly set forth that the parties should not be bound until there is a final written contract signed by authorized representatives of the parties but that they shall abstain from such measures which may defeat their stated objective to reach final agreement, e.g. by diminishing the value of performance under the contemplated contract.

• Korea Journal of Hospital Management
• /
• v.15 no.4
• /
• pp.1-26
• /
• 2010

We achieved both industrialization and democratization during the shortest period in the world. We also achieved good performance in national health insurance: universal coverage, solidarity in financing, equitable access of health care. However, national health insurance system has faced the problem of sustainability: various expenditure and financing problems. The problem of sustainablity has two facets of economic sustainability and fiscal sustainability. Economic sustainability refers to growth in health spending as a proportion of gross domestic product(GDP). Rapid increasing rate of health spending exceeds the growth rate of domestic product. Growth in health spending is more likely to threaten other areas of economic activity. Concern on fiscal sustainability relates to revenue and expenditure on health care. Health care financing face demographic and technical obstacles. Democratic obstacle is aging problem. Technical obstacle is collection of contribution. Expenditure of health care has various problems in benefit structure and efficiency of health care system. In this article, I suggest several policy reforms to enhance sustainability: generating additional revenue from value added tax, changing method of levying contribution, increasing efficiency of health care system by introducing the competition principle. restructuring of benefit scheme of health insurance. contracting with health care institutions to provide health care services.

• International Journal of Knowledge Content Development & Technology
• /
• v.11 no.3
• /
• pp.81-112
• /
• 2021

In this study, users' perceptions and concerns about digital information resources were investigated, focusing on impediments to the use of digital resources, to devise measures for improvement by identifying factors that hinder the use of digital information resources. To achieve the purpose of the study, the research identifies the inconvenien ce factors and establishes the user inconvenience list based on prior research and the current status survey. Based on the derived list, a survey was conducted on users of public libraries. Through this study, it was found that the use of digital information resources can be enhanced by improving the internal library system. Specifically, it refers to improving search performance and accessibility of digital data, providing one-stop services for digital information resources through the operation of an integrated data management system, conducting customized user education, and establishing a digital information resource preservation system, e.g. web archiving. Also, improving the external environment and system, such as contracting with more libraries for digitized data use agreements, strengthening support, unifying the names and classifications of digital information resources, and simplifying the procedure for using digital information resources, is of great importance.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.29 no.2
• /
• pp.55-66
• /
• 2021

ICAO recommended that airspace monitoring and periodic safety assessments in each Contracting State ensure the stability of the airspace, since reducing the aircraft lateral and vertical separation intervals would rather increase the risk of collision. The target level of safety of the AKARA-FUKUE Corridor at the southern end of Jeju was 247×10^-9. In simple comparison, this means that the risk of an aircraft collision in this area (international safety standards, 5.0×10^-9) is about 50 times higher. The scope of this study is to organize the concept of terms, analyze the air traffic volume, the current status of navigational safety facility usage fees, and investigations of an aircraft collision risk in Jeju southern air corridor. Analyzing government policies and overseas evaluations, revising some of the existing contents, presenting some of the additional contents of new routes, and changing the instrument procedure for Korean-Chinese routes, change of arrive/departure route between Incheon Airport and Shanghai Airport, reduce the risk of aircraft collisions. We hope to restore airspace sovereignty, contribute to policies for the government to take the lead in solving this problem, and expect stability and operational efficiency in air traffic.

• Korean Journal of Remote Sensing
• /
• v.37 no.5_3
• /
• pp.1475-1490
• /
• 2021

Detecting oil spill area using statistical characteristics of SAR images has limitations in that classification algorithm is complicated and is greatly affected by outliers. To overcome these limitations, studies using neural networks to classify oil spills are recently investigated. However, the studies to evaluate whether the performance of model shows a consistent detection performance for various oil spill cases were insufficient. Therefore, in this study, two CNNs (Convolutional Neural Networks) with basic structures(Simple CNN and U-net) were used to discover whether there is a difference in detection performance according to the structure of CNN and distribution characteristics of oil spill. As a result, through the method proposed in this study, the Simple CNN with contracting path only detected oil spill with an F1 score of 86.24% and U-net, which has both contracting and expansive path showed an F1 score of 91.44%. Both models successfully detected oil spills, but detection performance of the U-net was higher than Simple CNN. Additionally, in order to compare the accuracy of models according to various oil spill cases, the cases were classified into four different categories according to the spatial distribution characteristics of the oil spill (presence of land near the oil spill area) and the clarity of border between oil and seawater. The Simple CNN had F1 score values of 85.71%, 87.43%, 86.50%, and 85.86% for each category, showing the maximum difference of 1.71%. In the case of U-net, the values for each category were 89.77%, 92.27%, 92.59%, and 92.66%, with the maximum difference of 2.90%. Such results indicate that neither model showed significant differences in detection performance by the characteristics of oil spill distribution. However, the difference in detection tendency was caused by the difference in the model structure and the oil spill distribution characteristics. In all four oil spill categories, the Simple CNN showed a tendency to overestimate the oil spill area and the U-net showed a tendency to underestimate it. These tendencies were emphasized when the border between oil and seawater was unclear.

• Journal of the Korean Society of Systems Engineering
• /
• v.13 no.1
• /
• pp.79-88
• /
• 2017

For the PBL contract, it is necessary for the contracting parties to share information regarding the reasonable inventory-level and the cost of its repair parts for the estimated demand. There are various models which can be used for this purpose. Among them, V-METRIC model is considered to be the most efficient and is most frequently applied. However, this model is usually used for optimizing the inventory level of the repair parts of the system under operation. The model uses a time series forecast model to determine the demand rate, which is a mandatory input factor for the model, based on past field data. However, since the system at the deployment stage has no operational performance record, it is necessary to find another alternative to be used as the demand rate of the model application. This research applies the V-METRIC model to find the optimal inventory level and cost estimation for repairable items to meet the target operational availability, which is a key performance indicator, at the time of the PBL contract for the deployment system. This study uses the calculated value based on the allocated MTBF to the system as the demand rate, which is used as input data for the model. Also, we would like to examine changes in inventory level and cost according to the changes in target operational availability and MTBF allocation.