• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.8
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• pp.932-940
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• 1999

This paper discusses the development of an interactive and graphic software for the education and training of power system operation and control, especially for students and beginners. This software has a lot of functions for users to simulate the power system operation and control with ease. These functions included in this software are followings. First, this software includes a Graphic User Interface (GUI) - which contains interactive simulation scheme, Windows dialog box, graphic representations, and graphic icons - so that users can handle the software in user-friendly environments. Second, it uses a graphic editor so that users can easily edit the one-line diagram of the power system. Third, it prepares a database system so that users can manage the power system data for simulation easily. Fourth, the application modules included in the software are the Economic Dispatch (ED) and the Automatic Load-Frequency Control (ALFC). These application modules are designed as independent modules. Using the ED module, users can understand the basic concepts of the ED with ease. And using the ALFC module, they can easily acquire the basic understanding of the response of the ALFC between the two-area systems. The proposed software is tested on both the 16 bus and the two-area sample system. The test has confirmed the functions of the developed software. It is anticipated that the software will be useful for the education and training of power system operation and control for the power engineering study at university or for the training of the beginner at power industry.

• Cross-Cultural Studies
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• v.19
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• pp.181-204
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• 2010

This study analyzes the meaning of madness shown in the female narrative, focusing on two novels- "Before the Operation" by Mei Niang and "Madman's Diary" by Baek Shin-Ae. The novel "Before the Operation" reveals women's instinctive desires through an insane woman and brings up a problem of unfair suppression caused by patriarchism. On the other hand, the heroine of "Madman's Diary" shows madness when she is at a crisis to be 'the other' in the patriarchal system. Her madness is caused because she fails to find the meaning of her presence in the system. Interestingly, a woman who departs from moral standards of patriarchy (from "Before the Operation") becomes thefocus of public censure while a man (from "Madman's Diary") who also ignores those standards seems to be a victim. In "Madman's Diary", the man's wife is accused of being mad while he draws sympathy as a victim. This shows that those moral standards have duplicity. At this point, the heroines who continuously adjust themselves to the system express their madness. In other words, the madness implies a stern protest against the moral standards applied differently to men and women. It is unique that the two heroines of the novels become 'sane' when they encounter thematter of 'being a mother'. When it comes to "Madman's Diary", 'being a mother' of the insane woman who becomes 'the other' in the system foretells dismal future. Meanwhile, Mei Niang indicates the way- 'being a mother'- to overcome the dismal future through "Before the Operation". In this case, the mother is not a figure that reproduces the patriarchal power structure, but an independent figure who wants to change it. For that reason, 'being a mother' has the meaning of subversion and resistance.

• Journal of Advanced Navigation Technology
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• v.25 no.4
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• pp.273-279
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• 2021

A flight control computer(FLCC) applied to an unmanned aerial vehicle(UAV) is a safety-critical item, and which is designed in a multiple structure to increase the reliability of operation by securing fault tolerance. These FLCC of multiple structure should be designed so that each independent processing/control components can perform the same operation at the same time. And for this reason, a synchronization algorithm for synchronizing the operation between FLCCs should be included in an operational flight program. In this paper, we propose a software design method for synchronization between dual FLCCs applied to UAVs. The proposed synchronization method is designed to synchronize using only the minimum hardware resources to reduce a failure rate. In addition, the proposed synchronization method is designed to minimized synchronization errors due to a timer operation by designing in consideration of operation characteristics of the hardware timer used for the synchronization.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.135-140
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• 2022

Scientific and technological progress is also fundamental to the evolving merchant shipping industry, both in terms of the size and speed of modern ships and in the level of their technical capabilities. While the freight performance of ships is growing, the number of crew on board is steadily decreasing, as more work processes are being automated through the implementation of information technologies, including ship management systems. Although there have been repeated appeals from international maritime organizations to focus on building effective maritime security defenses against cyber attacks, the problems have remained unresolved. Owners of shipping companies do not disclose information about cyberattack attempts or incidents against them due to fear of commercial losses or consequences, such as loss of image, customer and insurance claims, and investigations by independent international organizations and government agencies. Issues of cybersecurity of control systems in the world today have gained importance, due to the fact that existing threats concern not only the security of technical means and devices, but also issues of environmental safety and safety of life at sea. The article examines the implementation of cyber risk management in the shipping industry, providing recommendations for the safe ship operation and its systems in order to improve vulnerability to external threats related to cyberattacks, and to ensure the safety and security of such a technical object as a seagoing ship.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.7
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• pp.753-759
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• 2009

As many systems depend on electronics in an intelligent vehicle, concern for fault tolerance is growing rapidly. For example, a car with its braking controlled by electronics and no mechanical linkage from brake pedal to calipers of front tires(brake-by-wire system) should be fault tolerant because a failure can come without any warning and its effect is devastating. In general, fault tolerance is usually designed by placing redundant components that duplicate the functions of the original module. In this way a fault can be isolated, and safe operation is guaranteed by replacing the faulty module with its redundant and normal module within a predefined interval. In order to make in-vehicle network fault tolerant, this paper presents the concept and design methodology of an IEEE 1451 based dual CAN module. In addition, feasibility of the dual CAN network was evaluated by implementing the dual CAN module.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.269-271
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• 2012

The chicken has been growing in Korea for more than a thousand years according to the history book and commercially rising for broiler meat only since 1960's. As income increased mainly due to improved economy, it changes the habit of eating especially chicken meat. The structure changes into a coordinated production and marketing system which forced the prevailed small and independent producers to become a contract farmer under the vertically controlled practices. This coordinated structure began in 1970's and evolved continually to occupy around 90 percent of the market in 2010 with some ten (10) private brands being advertising. The industrial organizations have also conducted the generic promotion by a farmer's check-off program. Over the past 20 years, chicken import steadily increased to meet about 25 percent of the domestic market while the export showed negligible growth. As a whole, the structure change and international trade devoted to increased chicken consumption from 2 kg with the independent operation to 11 kg currently under the coordinated system and import. It is predicted that chicken consumption will grow in years to come and the import will also increase in addition to local productions, considering the free trade agreement that has already been in practice with EU and US to open the market eventually from all sources of supply worldwide.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1821-1832
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• 2016

This study presents a strategy using the synchronized output regulation method (SOR) for controlling inverters operating in stand-alone and grid-connected modes. From the view point of networked dynamic systems, SOR involves nodes with outputs that are synchronized but also display a desirable wave shape. Under the SOR strategy, the inverter and grid are treated as two nodes that comprise a simple network. These two nodes work independently under the stand-alone mode. An intermediate mode, here is named the synchronization mode, is emphasized because the transition from the stand-alone mode to the grid-connected mode can be dealt as a standard SOR problem. In the grid-connected mode, the inverter operates in an independent way, in which the voltage reference changes for generalized synchronization where its output current satisfies the required power injection. Such a relatively independent design leads to a seamless transfer between operation modes. The closed-loop system is analyzed in the state space on the basis of the output regulation theory, which improves the robustness of the design. Simulations and experiments are performed to verify the proposed control strategy.

• Journal of Communications and Networks
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• v.12 no.3
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• pp.266-274
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• 2010

The efficient network resource management is one of the important topics in a real-time system. In this paper, we present a practical network resource management framework, control-theoretic packet scheduler (CPS) system. Using our framework, an operating system can schedule both input and output streams accurately and efficiently. Our framework adopts very portable feedback control theory for efficiency and accuracy. The CPS system is able to operate independent of the internal network protocol state, and it is designed to schedule packet streams in fine-grained time intervals to meet the resource requirement. This approach simplifies the design of the CPS system, and leads us to obtain the intended output bandwidth. We implemented our prototype system in Linux, and measured the performance of the network resource management system under various network QoS constraints. The distinctive features of our principles are as follows: It is robust and accurate, and its operation is independent of internal network protocols.

• Journal of Communications and Networks
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• v.6 no.1
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• pp.60-67
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• 2004

With the fast growth of Internet and a new widespread interest in optical networks, the unparalleled potential of Multi-Protocol Label Switching (MPLS) is leading to further research and development efforts. One of those areas of research is Path Protection Mechanism. It is widely accepted that layer three protection and recovery mechanisms are too slow for today’s reliability requirements. Failure recovery latencies ranging from several seconds to minutes, for layer three routing protocols, have been widely reported. For this reason, a recovery mechanism at the MPLS layer capable of recovering from failed paths in 10’s of milliseconds has been sought. In light of this, several MPLS based protection mechanisms have been proposed, such as end-to-end path protection and local repair mechanism. Those mechanisms are designed for intra-domain recoveries and little or no attention has been given to the case of non-homogenous independent inter-domains. This paper presents a novel solution for the setup and maintenance of independent protection mechanisms within individual domains and merged at the domain boundaries. This innovative solution offers significant advantages including fast recovery across multiple nonhomogeneous domains and high scalability. Detailed setup and operation procedures are described. Finally, simulation results using OPNET are presented showing recovery times of a few milliseconds.

• Journal of Gastric Cancer
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• v.10 no.3
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• pp.126-132
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• 2010

Purpose: Peritoneal carcinomatosis (PC) has a dismal prognosis and is occasionally encountered during initial exploration in patients with gastric cancer. The clinicopathological characteristics and survival were analyzed in patients with gastric cancer and PC. Materials and Methods: Among 2,083 gastric cancer patients who received surgery at the department of surgery, Hanyang University Hospital from 1992 to 2009, 130 patients revealed PC. Ten patients who were lost during follow-up were excluded. The remaining 120 patients were divided into three groups according to the type of surgery. The degree of PC was classified into P1(to the adjacent peritoneum) and P2 (to the distant peritoneum). Various other clinicopathological factors were analyzed using univariate and multivariatec survival analyses. Results: Systemic chemotherapy (SC), type of surgery, lymph node dissection, degree of PC, and presence of ascites were significant prognostic factors. However, age, gender, resection of PC, and Borrmann type were not significant prognostic factors. In a multivariate analysis, SC and the degree of PC were independent prognostic factors. The survival benefit of SC was significant without reference to the type of surgery or degree of PC. Conclusions: A gastrectomy should be considered feasible in patients with gastric cancer and PC. The independent favorable prognostic factors were SC and a low degree of PC. SC improved the prognosis regardless of operation type and degree of PC.