• Molecules and Cells
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• v.38 no.5
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• pp.390-395
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• 2015

Degradation of chlorophyll (Chl) by Chl catabolic enzymes (CCEs) causes the loss of green color that typically occurs during senescence of leaves. In addition to CCEs, STAYGREEN1 (SGR1) functions as a key regulator of Chl degradation. Although sgr1 mutants in many plant species exhibit a staygreen phenotype, the biochemical function of the SGR1 protein remains elusive. Many recent studies have examined the physiological and molecular roles of SGR1 and its homologs (SGR2 and SGR-LIKE) in Chl metabolism, finding that these proteins have different roles in different species. In this review, we summarize the recent studies on SGR and discuss the most likely functions of SGR homologs.

• Communications for Statistical Applications and Methods
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• v.20 no.6
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• pp.481-490
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• 2013

Classification is an important research area as data can be easily obtained even if the number of predictors becomes huge. The support vector machine(SVM) is widely used to classify a subject into a predetermined group because it gives sound theoretical background and better performance than other methods in many applications. The SVM can be viewed as a penalized method with the hinge loss function and penalty functions. Instead of $L_2$ penalty function Fan and Li (2001) proposed the smoothly clipped absolute deviation(SCAD) satisfying good statistical properties. Despite the ability of SVMs, they have drawbacks of non-robustness when there are outliers in the data. We develop a robust SVM method using a weight function with the SCAD penalty function based on the local quadratic approximation. We compare the performance of the proposed SVM with the SVM using the $L_1$ and $L_2$ penalty functions.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.45-46
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• 1995

Alzheimer's disease is believed to be associated with the loss of cholinergic activity in the cortex and hippocampus. In addition, it has been reported that the monoaminergic systems which also controls brain functions are disturbed in Alzheimer's patients. Based on these neurochemical background, a number of cholinesterase inhibitors including tacrine and its analogues and some monoamine oxidase inhibitors such as L-deprenyl and monoamine reuptake inhibitors have been developed for the treatment of dementia, but all of the known drugs are not truly effective. We thought that a drug that activates only one neurotransmitter system is not effective enough for the treatment of the symptoms associated with Alzheimer's disease and vascular dementia, and we conceived that an agent enhancing both central cholinergic and monoaminergic functions would be useful for the treatment of dementia

• Journal of Electrical Engineering and information Science
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• v.3 no.3
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• pp.322-329
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• 1998

Stability analysis of nonlinear systems is mostly based on the Lyapunov stability theory. The well-known Lyapunov function method provides precise and rigorous theoretical backgrounds. However, the conventional approach to direct stability analysis has been performed without taking account of damping effects, which is pointed as a minor but crucial drawback. For accurate has been performed without taking account of damping effects, which is pointed as a minor but crucial drawback. For accurate stability analysis of nonlinear systems, it is required to take the damping effects into account. This paper presents a new method to derive a group of Lyapunov functions to reflect the damping effects by considering the integral relationships of the system governing equations. A systematical approach is developed to convert a part of damping loss into some appropriate system energy terms. Examples show that the proposed method remarkably improves the estimation of the region of attraction compared considering damping effects. The proposed method can be utilized as a useful tol to determine the region of attraction.

• The Korean Society of Law and Medicine
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• v.13 no.2
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• pp.179-214
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• 2012

There are two opinions on the legal characteristics of damages for non-pecuniary loss, a private sanctions theory and complementary function of damages for non-pecuniary loss, briefly. There is a close connection between the legal characteristics and the function of damages for non-pecuniary loss. The functions of damages for non-pecuniary loss are consist of satisfaction, prevention( sanctions) and complementation. Several cases of medical injury relief reported to Korea Comsumer Agency are categorized as follows, 1) cases of death after having an operation, 2) diagnosed with disability after a medical accident, 3) extended damages happening related to delayed diagnosis, 4) et cetera(a plastic surgery, a treatment with oriental medicine), and the damages for non-pecuniary loss in respect to each cases are examined. In the case of occurring death or disability, Korea Comsumer Agency has set up guidelines for assessment of damages for non-pecuniary loss by classifying into major and collateral violation for a duty of care. Furthermore, the damages for non-pecuniary loss in the case of all sorts of cancers, are assessed in accordance with the degree of responsibility subsequent to dividing cancer into good and poor prognosis. When it comes to a complementary function of damages for non-pecuniary loss in the actual work, it is hard to assess the damages as it is difficult to objectify non-pecuniary loss, such as emotional distress. Though compensation for damages is major legal characteristics of consolation money, preventing a damage(private sanctions) through consolation for a victim or sanctions against an assailant also has great significance. Therefore, it is necessary to approach flexibly for mutual agreement by considering specialty( concrete facts) of individual issue thoroughly. If considering this aging society that limits the possible age for work to 60 years old, it is needed to have a complementary function of consolation money in mind not to make it less meaningful for victims due to small sum of consolation money.

• Earthquakes and Structures
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• v.5 no.4
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• pp.439-459
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• 2013

Main objective of the present study is to determine the statistical properties and suitable probability distribution functions of spectral displacements from nonlinear static and nonlinear dynamic analysis within the frame work of Monte Carlo simulation for typical low rise and high rise RC framed buildings located in zone III and zone V and designed as per Indian seismic codes. Probabilistic analysis of spectral displacement is useful for strength assessment and loss estimation. To the author's knowledge, no study is reported in literature on comparison of spectral displacement including the uncertainties in capacity and demand in Indian context. In the present study, uncertainties in capacity of the building is modeled by choosing cross sectional dimensions of beams and columns, density and compressive strength of concrete, yield strength and elastic modulus of steel and, live load as random variables. Uncertainty in demand is modeled by choosing peak ground acceleration (PGA) as a random variable. Nonlinear static analysis (NSA) and nonlinear dynamic analysis (NDA) are carried out for typical low rise and high rise reinforced concrete framed buildings using IDARC 2D computer program with the random sample input parameters. Statistical properties are obtained for spectral displacements corresponding to performance point from NSA and maximum absolute roof displacement from NDA and suitable probability distribution functions viz., normal, Weibull, lognormal are examined for goodness-of-fit. From the hypothesis test for goodness-of-fit, lognormal function is found to be suitable to represent the statistical variation of spectral displacement obtained from NSA and NDA.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.664-667
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• 2003

We propose a frizzy traffic controller of Sugeno's fuzzy model so as to model the nonlinear characteristics of controlling the traffic light. It uses a degree of the traffic congestion of the preceding roads as an input so that it can cope with traffic congestion appropriately, which causes the loss of fuel and our discomfort. In order to construct fuzzy traffic controller of Sugeno's fuzzy model we first model the control process of the traffic light by using Mamdani's fuzzy model, which has the uniform membership functions of the same size and shape. Next we make Mamdani's fuzzy model with the non-uniform membership functions so that it can exactly reflect the knowledge of experts and operators. Lastly, we construct the fuzzy traffic controller of Sugeno's fuzzy model by learning from the input/output data, which is retrieved from Mamdani's fuzzy model with the non-uniform membership functions. We compared and analyzed the service level of the traffic light controllers by using the delay time. As a result of comparison, the fuzzy traffic controller of Sugeno's fuzzy model shows the best service level of them.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.209-210
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• 2008

In the case of unauthorized individuals, systems and entities or process threatening the instrumentation and control systems of nuclear facilities using the intrinsic vulnerabilities of digital based technologies, those systems may lose their own required functions. The loss of required functions of the critical systems of nuclear facilities may seriously affect the safety of nuclear facilities. Consequently, digital instrumentation and control systems, which perform functions important to safety, should be designed and operated to respond to cyber threats capitalizing on the vulnerabilities of digital based technologies. To make it possible, the developers and licensees of nuclear facilities should perform appropriate cyber security program throughout the whole life cycle of digital instrumentation and control systems. Under the goal of securing the safety of nuclear facilities, this paper presents the KINS' regulatory position on cyber security program to remove the cyber threats that exploit the vulnerabilities of digital instrumentation and control systems and to mitigate the effect of such threats. Presented regulatory position includes establishing the cyber security policy and plan, analyzing and classifying the cyber threats and cyber security assessment of digital instrumentation and control systems.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.37-43
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• 2014

Nuclear power plants(NPPs) are consisted of power production functions and safety functions preventing leakage of radiation. Operators working in NPPs shall maintain these functions during an operation period through various activities such as improvement & modification, corrective maintenance, preventive maintenance and surveillance test. According to the performance of these work activities, there are configuration changes in NPPs systems. Its changes cause the increase of safety risks(CDF) and plant trip risks. Recently, the importance of risk management is increasing gradually in the operation process of NPPs. Therefore, this paper presents the work management methods using the various risk monitoring systems during power operation and overhaul period. Also this paper suggests the optimum application ways of risk systems for work management.

• Journal of Korea Port Economic Association
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• v.18 no.1
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• pp.61-83
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• 2002

Korea has designated 28 trade ports and 22 coastal ports under the Ports Act. If fishery ports and small inlets are counted, the number amounts to hundreds of ports. However, untimely and inefficient maintenance and repair works face Korean ports with functional loss, decreasing efficiency, and even catastrophe. Thus, further examinations on the maintenance or redevelopment of forts in Korea are urgent. Since the Korean War and the higher economic growth period in the 1970s, Busan Port has developed in a variety of ways, according to the necessity of social conditions at any given time, without any development Philosophy or systematic long-term master plan. As a result, ports and coastal industrial facilities have rushed to gather around the present North Busan Port, which has taken on mixed functions between ports and cities, adversely affecting several of their interactions. To resolve these circumstances, several redevelopment schemes were suggested for centering the old zone in the Busan Port interim. However, comprehensive evaluation and redevelopment schemes combining functions of both ports and cities, and effectively utilizing coastal zones have never been presented. In this respect, this study sets the priority order of the extracted unit project. This study analyzes the existing functions and facilities of Busan Port, extracting facility zones through redevelopment which is certain to fail or to decrease in efficiency. furthermore, this study presents status and development directions of specified redevelopment unit projects of higher priority order, and pursues the integrated plan of efficiency for Busan Port.