• Convergence Security Journal
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• v.23 no.4
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• pp.23-32
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• 2023

Container-based virtualization has attracted many attentions as an alternative to virtual machine technology because it can be used more lightly by sharing the host operating system instead of individual guest operating systems. However, this advantage may owe some vulnerabilities. In particular, excessive resource use of some containers can affect other containers, which is known as the noisy neighbor problem, so that the important property of isolation may not be guaranteed. The noisy neighbor problem can threat the availability of containers, so we need to consider the noisy neighbor problem as a security problem. In this paper, we investigate vulnerabilities on guarantee of isolation incurred by the noisy neighbor problem in container-based virtualization. For this we first analyze the structure of container-based virtualization environments. Then we present vulnerabilities in 3 functional layers and general directions for solutions with limitations.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.2
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• pp.107-116
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• 2003

This paper presents a systematic design methodology for fault tolerant controller against a fault in actuators and sensors of linear stochastic systems with uncertainties. The scheme is based on fault detection and diagnosis(isolation and estimation) using a bank of robust two-stage Kalman filters, and accommodation of the actuator fault by eigenstructure assignment and immediate compensation of the sensor's faulty measurement. In order to clarify the fault feature in test statistics of residual, noise reduction method is given by multi-scale discrete wavelet transform. The effectiveness of our approach Is shown via simulations for a VTOL(vertical take-off and landing) aircraft subjected to parameter variations, external disturbances, process and sensor noises.

• KIEAE Journal
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• v.4 no.3
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• pp.187-194
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• 2004

In many other buildings, hospital is very important because of its function and purpose. A proper building service systems including heating, cooling, ventilation and plumbing systems is required in hospial. Besides, a special systems like medical gas, vacuum cleaning systems are required to prevent contamination as well as cure a patient in hospital. Ventilation is very important method to keep the indoor pressure and clean class. There are some specific rooms to consider clean class and indoor pressure in the general hospital. In this article, specific rooms were set to operating room, laboratory, ICU, isolation unit, and sterilizer room. In this case study, design factors of ventilation system, including air changes of OA and TA, indoor pressure, clean class, filter, and material of system, of specific rooms in hospital were proposed through a literature research and a design examples review.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.4
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• pp.270-276
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• 2002

An integrated robust fault diagnosis and fault accommodation strategy for a class of linear stochastic systems subjected to unknown disturbances is presented under the assumption that only a single fault may occur at a given time. The strategy is based on the fault isolation and estimation using a bank of robust two-stage Kalman filters and introduction of the additive compensation input for cancelling out the fault's effect on the system. Each filter is set up such that the residual is decoupled from unknown disturbances and fault with the influence vector designed in the filter. Simulation results for the simplified longitudinal flight control system with parameter uncertainties, process and sensor noises demonstrate the effectiveness of the present approach.

• International Journal of Control, Automation, and Systems
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• v.6 no.3
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• pp.339-350
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• 2008

A general active fault-tolerant control framework is proposed for nonlinear systems with sensor faults. According to their identifiability, all sensor faults are divided into two classes: identifiable faults and non-identifiable faults. In the healthy case, the control objective is such that all outputs converge to their given set-points. A fault detection and isolation module is firstly built, which can produce an alarm when there is a fault in the system and also tell us which sensor has a fault. If the fault is identifiable, the control objective remains the same as in the healthy case; while if the fault is non-identifiable, the control objective degenerates to be such that only the healthy outputs converge to the set-points. A numerical example is given to illustrate the effectiveness and feasibility of the proposed method and encouraging results have been obtained.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.710-713
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• 1995

Hopfield networks have been applied to the problem of linear system identification. In this paper, Hopfield network based parameter identification scheme of non-linear dynamic systems is proposed. Simulation results demonstrate that Hopfield network can be used effectively for the identification of non-linear systems assuming that the system states and their time derivatives are available. Therefore, the proposed scheme can be applied in fault detection and isolation(FDI) and adaptive control of non-linear systems where the Hopfield networks perform on-line identification of system parameters.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.125-129
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• 2006

This paper presents the isolation and performance evaluation of PV systems installed at Tibet area of China in order to identity the key factors that determines system operation at a severe climate conditions and promote the cooperation of PV technology between Korea and China. The installed systems consist of 100kW on-grid connected PV systems, BOS(balance of systems), data acquisition and transmission equipments. The Korea side supplied the solar cell, BOS like as inverter, control box and monitoring system. And the Chinese side assembled solar module by using Koreans solar cells, constructed site and built control house.

• International Journal of High-Rise Buildings
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• v.6 no.3
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• pp.227-235
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• 2017

This paper describes some of the challenges for structural design of a mid-story seismic isolated high-rise building, which is located near Tokyo station, completed in 2015. The building is a mixed-use complex and encompasses three volumes: one substructure including basement and lower floors, and a pair of seismic isolated superstructures on the substructure. One is a 136.5m high Main Tower (office use), and the other is a 98.5 m high South Tower (hotel use). The seismic isolation systems are arranged in the $3^{rd}$ floor of the Main Tower and $5^{th}$ floor of the South Tower, so that we call this isolation system as the mid-story seismic isolation. The primary goal of the structural design of this building was to secure high seismic safety against the largest earthquake expected in Tokyo. We adopted optimal seismic isolation equipment simulated by dynamic analysis to minimize building damage. On the other hand, wind-induced vibration of a seismic isolated high-rise building tends to be excited. To reduce the vibration, the following strategies were adopted respectively. In the Main Tower with a large wind receiving area, we adopted a mechanism that locks oil dampers at the isolation level during strong wind. In the South Tower, two tuned mass dampers (TMDs) are installed at the top of the building to control the vibration. In addition, our paper will also report the building performance evaluated for wind and seismic observation after completion of the building. In 2016, an earthquake of seismic intensity 3 (JMA scale) occurred twice in Tokyo. The acceleration reduction rate of the seismic isolation level due to these earthquakes was approximately 30 to 60%. These are also verified by dynamic analysis using observed acceleration data. Also, in April 2016, a strong wind exceeding the speed of 25m/s occurred in Tokyo. On the basis of the record at the strong wind, we confirmed that the locking mechanism of oil damper worked as designed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.601-611
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• 2016

The research, development and use of seismic isolation systems have been increasing with the gradual development of structure safety assurance methods for earthquakes. The High Damping Rubber Bearing (HDRB), one type of seismic isolation system, is a Laminated Rubber Bearing using special High Damping Rubber. However, as its damping function is slightly lower than that of the Lead Rubber Bearing, a similar seismic isolation system, its utilization has not been high. However, the HDRB has a superior damping force to the Natural Rubber Bearing, which has similar materials and shapes, and the existing Lead Rubber Bearing has a maleficence problem in that it contains lead. Thus, studies on HDRBs that do not use lead have increased. In this study, a test targeting the HDRB was done to examine its various dependence properties, such as its compressive stress, frequency and repeated loading. To evaluate the HDRB's seismic performance in response to several earthquake waves, the shaking table test was performed and the results analyzed. The test used the downscaled bridge model and the HDRB was divided into seismic and non-seismic isolation. Consequently, when the HDRB was applied, the damping effect was higher in the non-seismic case. However, its responses on weak foundations, such as in Mexico City, represented increased shapes. Thus, its seismic isolator.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.1
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• pp.99-110
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• 2016

In Korea and China, traditional medicine's holistic approaches, based on the views of whole-body and whole-person, have been applied to make the solution of health problem. However, these holistic approaches of traditional korea or chinese medicine have been limited in interpreting their theories in a view of modern scientific aspects of medicine. This limitation seems to be mainly due to the reductionism approaches of modern scientific medicine. Traditionally, science has taken a reductionism approach; dissecting biological systems into their constituent parts and studying them in isolation. However, systems biology based on omics technologies is providing a new thought and method for traditional medicine's research and interpretation. Systems biology uses integrity study as the characteristic and bioinformatic technology as the key method for connecting reductionism and holism. Therefore, it has much in common with the theory of traditional medicine. It was reviewed that how systems biology is applied to traditional medicine in Korea and China. Also it was suggested that more future researches on interpretation between traditional medicine and systems biology must be focused on personalized medicine since systems biology will have a major impact on future personalized therapeutic approaches.