• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.586-588
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• 1999

A robust controller design methodology is proposed, where the proposed controller consists of a servo controller at the outer loop as well as the robust internal-loop compensator (RIC) to eliminate the model uncertainty and external disturbance. It is shown that RIC is general structure of DOB and ARC. Numerical example is illustrated to show validities of the proposed robust controller.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.1
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• pp.241-248
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• 2024

Socially, organizations are required to effectively manage their information resources, both in terms of acquiring information from external sources and safeguarding against potential breaches by insiders. While information security policies and technologies implemented by organizations contribute to achieving internal security, an overly complex or disorganized security structure can create uncertainty among employees. In this study, we identify factors of structural information security (IS)-related uncertainty within organizations and propose that they contribute to non-compliance. We develop a research model and hypotheses based on previous studies on the information security environment and test these hypotheses using structural equation modeling. Our findings indicate that uncertainties related to IS policy, technology, and communication decrease employees' IS role identity and their intention to comply with IS measures. By addressing these uncertainties, organizations can improve their IS environment and work towards achieving there is goals.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.64-71
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• 2018

Project Management Institute of America separates the types of risk with external risks and internal risks. The external risk is an uncontrollable risk in projects such as changes of policy and related systems, climate, natural disasters, exchange rates and so on. The internal risk is an existing risk in the project itself that is controllable items in the project. Technical risks in project management are cost, quality, time, safety and environment. Therefore, both the external and internal risks should be managed to perform the construction project successfully. In particular, we can secure the quality and safety of facilities through the technical risk management. The importance of potential risk management has been emerging as a major interest and the lack of risk management delays projects and increases construction costs with negative effects of the building safety since the complex building, which is composed of a great number of facilities, consists of many project units and there are conflicts between various participants and stake-holders. This study presents the ways of establishing risk management processes to ensure the safety of the complex building. To that end, establishing procedure of risk management processes is presented and types of risk and factors in construction projects and counter strategies are presented as available risk information on the stages.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.519-527
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• 2016

The demand of construction risk analysis is rapidly increased to improve the competitiveness of construction companies and the sound management of the construction project. However, estimating the amount and uncertainty of the risk is difficult due to the wide range of risks in the construction industry. Moreover, most of the research on risk management of construction risk is only focused on the causes of risk without separate the internal and external risk. This study statistically analysis the internal risk and external risk based on the accidents cases which are caused at construction sites to define the difference and importances of the risk. An accident cause analysis and T-test analysis are carried out to reach the goal of study. The results of the study are expected to be used as a guideline of construction project risk analysis.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.2
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• pp.145-154
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• 2023

In this study, to control the heading angle of a ship, which is constantly subjected to various internal and external disturbances during the voyage, an LADRC (linear active disturbance rejection control) design that focuses more on improving the disturbance removal performance was proposed. The speed rate of change of the ship's heading angle due to the turn of the rudder angle was selected as a significant factor, and the nonlinear model of the ship's maneuvering equation, including the steering gear, was treated as a total disturbance. It is the similar process with an LADRC design for the first-order transfer function model. At this time, the gains of the controller included in LADRC and the gains of the extended state observer were tuned to RCGAs (real-coded genetic algorithms) to minimize the integral time-weighted absolute error as an evaluation function. The simulation was performed by applying the proposed GA-LADRC controller to the heading angle control of the Mariner class vessel. In particular, it was confirmed that the proposed controller satisfactorily maintains and follows the set course even when the disturbances such as nonlinearity, modelling error, uncertainty and noise of the measurement sensor are considered.

• International Commerce and Information Review
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• v.12 no.2
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• pp.325-355
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• 2010

Knowledge-based exporting companies in Korea have reached a stage to develop new technological innovation and to pioneer new markets. But, developing new technologies and launching new products require an enormous sum of money for Research and Development(R&D) and there is still uncertainty in technological development and markets. Therefore, through open technological innovation, they are encouraged to actively use external technological sources and ideas. They also need to enhance the efficiency of the relatively little R&D investment. In this paper, firstly, it conducts a precedent study on the concept and influence factors of knowledge-based exporting companies and open technological innovation. Secondly, it sets a study model and estimates a regression coefficient to analyze the influence factors of open technological innovation of knowledge-based exporting companies which are using external resources on the process of innovation. Through case study and empirical analysis, we are going to find the implication of open technological innovation and prepare the way of the innovation for the knowledge-based exporting companies. According to the empirical analysis, variables such as firm size, processing degree, product life, patent registration, maintaining internal security didn't have positive effects on open innovation performance. On the other hand, research capability and market preoccupancy had positive effects. Therefore, to succeed in open innovation, knowledge-based exporting companies not only need to secure research capability through open innovation, but also need to preoccupy the market through commercialization of developed product.

• Korea Journal of Hospital Management
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• no.spc
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• pp.85-95
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• 2016

This study is to introduce a comprehensive framework of a crisis management system developed at a prominent hospital in South Korea. Throughout recent decades, especially in the recent years, the way in which to cope with both internal and external challenges has been one of the most critical issues. Since the incident management system in the U.S. is acknowledged as the most advanced crisis management model in the world, a portion of this study refers to the Hospital Incident Command System(HICS) provided by the California Emergency Medical Services Authority(EMSA). Nevertheless, the framework suggested in this article was designed based on a distinctive Korean hospital setting. The main contents of this study are as follows; categorization of each type of crisis, organization of a crisis management team in a non-crisis or crisis state, crisis assessment by life cycle stage, and establishment of crisis management protocol. Even though many types of crises are unspecified, those can be categorized into external crisis, medical crisis, and utility & activity failure. A crisis management organization should be operated and consisted differently- depending on a crisis or non-crisis situation. From a life-cycle perspective, the range by which the crisis should be managed extends from pre-stage to post-stage of the crisis. It is important to set proper scenarios and manuals by crisis type to develop a crisis management framework of high quality. With continuous efforts, hospitals can prepare for the uncertainty to better concentrate on core business operations.

• Korean System Dynamics Review
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• v.5 no.2
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• pp.199-216
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• 2004

The present study is aimed at developing the optimal instruments for dispelling the uncertainty factors during the formulation of strategies for corporate development. The objective is the creation of a complete model of strategic analysis, which encompasses both the environment (internal and external) and the management rational component. This model -built on the analysis of three corporate cases - is concretized by a simulation for testing the strategy by the means of software which enables the users to cope with a dynamic and complex corporate environment. The research questions regard the development of a complete strategic analysis, which covers the entire decision-making process; the concrete assessment of the business strategy on the basis of quantitative data: the identification and enhancement of the critical variables of business administration, in such a complex and dynamic reality as the corporate environment.

• Smart Structures and Systems
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• v.25 no.6
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• pp.643-655
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• 2020

Active control of nonlinear vibration of stiffened functionally graded (SFG) cylindrical shell is studied in this paper. The system is subjected to axial and transverse periodic loads in the presence of thermal uncertainty. The material composition is considered to be continuously graded in the thickness direction, also these properties depend on temperature. The relations of strain-displacement are derived based on the classical shell theory and the von Kármán equations. For modeling the stiffeners on the cylindrical shell surface, the smeared stiffener technique is used. The Galerkin method is used to discretize the partial differential equations of motion. Some comparisons are made to validate the SFG model. For suppression of the nonlinear vibration, the linear and nonlinear control strategies are applied. For control objectives, the piezoelectric actuator is attached to the external surface of the shell and the thin ring piezoelectric sensor is attached to the middle internal surface of shell. The effect of PID, feedback linearization and sliding mode control on the suppression of vibration for SFG cylindrical shell is presented.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.217-218
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• 2017

In this study, we analyzed the main factors contributing to SCM quality improvement. The external factors influencing the SCM are environmental aspects and aspects of cooperation with other companies. Internal factors include agility management, flexibility management, and uncertainty management. We analyzed how the factors on each side can improve the quality of SCM and proposed new measures to improve overall SCM performance.