• KIEE International Transactions on Power Engineering
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• v.2A no.3
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• pp.114-120
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• 2002

This paper describes the symptoms with the fault causes of pole transformers analyzed by Korea Electric Power Corporation(KEPCO) branch offices' request in 2001, and ultimately aims to devise proper countermeasures against the faults. The fault causes are generally divided into problems in manufacturing, mounting and operating. The pole transformers encounter the fault with unique aging mechanisms. To verify the mechanisms with the faults and to devise proper countermeasures, a flowchart for analyzing the fault causes is proposed, by which the fault causes of the pole transformers can be analyzed more exactly.

• Clinical and Experimental Pediatrics
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• v.60 no.1
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• pp.1-9
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• 2017

Malformations of cortical development are rare congenital anomalies of the cerebral cortex, wherein patients present with intractable epilepsy and various degrees of developmental delay. Cases show a spectrum of anomalous cortical formations with diverse anatomic and morphological abnormalities, a variety of genetic causes, and different clinical presentations. Brain magnetic resonance imaging has been of great help in determining the exact morphologies of cortical malformations. The hypothetical mechanisms of malformation include interruptions during the formation of cerebral cortex in the form of viral infection, genetic causes, and vascular events. Recent remarkable developments in genetic analysis methods have improved our understanding of these pathological mechanisms. The present review will discuss normal cortical development, the current proposed malformation classifications, and the diagnostic approach for malformations of cortical development.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.503-507
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• 2002

This paper describes the symptoms with the failure causes of pole transformers analyzed at KEPCO branch offices' request in 2001, and ultimately aims for devising proper countermeasures against the failures. The failure causes are generally divided into problems in manufacturing, mounting and operating. The pole transformers encounter the failure with unique mechanisms. To verify the mechanisms to failures and help devise proper countermeasures, a flowchart is proposed based on the authors' experience and foreign case studies. The failure causes of pole transformers can be analyzed more exactly by using the flowchart.

• Osteoporosis and Sarcopenia
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• v.3 no.3
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• pp.117-122
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• 2017

Sarcopenia is the degenerative loss of muscle mass and function with aging. Recently sarcopenia was recognized as a clinical disease by the International Classification of Disease, 10th revision, Clinical Modification. An imbalance between protein synthesis and degradation causes a gradual loss of muscle mass, resulting in a decline of muscle function as a progress of sarcopenia. Many mechanisms involved in the onset of sarcopenia include age-related factors as well as activity-, disease-, and nutrition-related factors. The stage of sarcopenia reflecting the severity of conditions assists clinical management of sarcopenia. It is important that systemic descriptions of the disease conditions include age, sex, and other environmental risk factors as well as levels of physical function. To develop a new therapeutic intervention needed is the detailed understanding of molecular and cellular mechanisms by which apoptosis, autophagy, atrophy, and hypertrophy occur in the muscle stem cells, myotubes, and/or neuromuscular junction. The new strategy to managing sarcopenia will be signal-modulating small molecules, natural compounds, repurposing of old drugs, and muscle-specific microRNAs.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.1-7
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• 2021

Bacterial biofilm is a community of bacteria that are embedded and structured in a self-secreted extracellular matrix. An important clinical-related characteristic of bacterial biofilms is that they are much more resistant to antimicrobial agents than the planktonic cells (up to 1,000 times), which is one of the main causes of antibiotic resistance in clinics. Therefore, infections caused by biofilms are notoriously difficult to eradicate, such as lung infection caused by Pseudomonas aeruginosa in cystic fibrosis patients. Understanding the resistance mechanisms of biofilms will provide direct insights into how we overcome such resistance. In this review, we summarize the characteristics of biofilms and chronic infections associated with bacterial biofilms. We examine the current understanding and research progress on the major mechanisms of antibiotic resistance in biofilms, including quorum sensing. We also discuss the potential strategies that may overcome biofilm-related antibiotic resistance, focusing on targeting biofilm EPSs, blocking quorum sensing signaling, and using recombinant phages.

• Korean System Dynamics Review
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• v.15 no.4
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• pp.29-60
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• 2014

As every commentators has noted, bureaucratic corruption, which has complicated causes, is prevalent phenomenon in Korean society. Especially, most people realize that systemic corruption has a strong negative effect on society; however, only few studies reflect on the nature of 'systemic corruption' and it seems that no established theory explains the phenomenon. Thus, this study suggest that we look more carefully into the nature and mechanisms of 'systemic corruption'. Interdisciplinary approach based on the integrated model of structure-behavior to analyse the nature of bureaucratic corruption. The system dynamics method can test the mechanisms of 'systemic corruption'. With this way, the factors generating systemic corruption represent the relationships reinforcing and balancing within system dynamics model. This paper also consider 'isomorphism' and 'dominance' as control mechanisms to systemic corruption. From the CLD(Causal Loop Diagram), three main areas(rent in organization, networking, control mechanisms) are overlapped and it indicates dynamic relationships of systemic corruption in organizations.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.10a
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• pp.58-61
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• 1992

Water potential which controls miosture movement in concrete is a kind of stress which causes concrete shrinks or expands. Therefore, there is a straightforward relationship between the water potential and the shrinkage strain. Explicit equations which show the relationships between the two parameters were derived through rational process. Two micro mechanisms among three shrinkage mechanisms were considered in the theory. Thermocouple psychrometer were embedded in a concrete slab to measure the water potential and also to find a correlation with the shrinkage. The test results prove the validity of the theory, and show the way to utilize the delived equations.

• Journal of Trauma and Injury
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• v.19 no.1
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• pp.1-7
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• 2006

Purpose: Injury is a leading cause of morbidity and mortality for children. As an injury prevention measure, the differences in external causes of severe pediatric injuries based on ICECI were analyzed according to age groups. Methods: A retrospective study was performed for pediatric patients under 15 years of age, who had been admitted to the emergency department with severe injuries from January 1998 to December 2004. The external causes of injury were investigated according to the ICECI: intent, mechanisms, places of occurrence, objects/substances producing injury, and related activities. The patients were divided into four groups based on age: infant (<0 year), toddler (1~4 years), preschool age (5~8 years), and school age (9~15 years). Results: The injury mechanisms, the places of occurrence and the related objects/substances vary with the age groups. The most common subtype of traffic accidents was pedestrian injury in pre-school age group. Falls most frequently occurred in the toddler group. But falls from a height of less than l meter height (6 patients) occurred only in the infant group. The most common place of occurrence in the infant group was the home, and that of other groups was the road. The related objects/substances for falls, for example, household furnitures and playground equipment depended on the age group. Conclusion: The age-group specific characteristics of severe pediatric injury were analyzed successfully through the ICECI. Therefore, when establishing a plan for the prevention of pediatric injury, consideration must be given to the differences in the external causes of injuries according to age group.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.04a
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• pp.50-52
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• 1990

Although concrete pavements were successfully widespread throughout the nation due to the desirable surface characteristics, durability, and economy, it still causes several transverse cracking and joint failure problems in some areas. In this paper, the major emphasis was given to provide a rational analytical approach on joint failure mechanisms, considering several sets of joint stiffnesses on different subgrade moduli. Besides , load transfer mechanisms on concrete pavement joints were highlighted with finite element method and computer modeling.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.463-469
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• 2006

Sodium is the major cation of the extracellular fluid and the primary determinant of extracellular osmolality. Therefore, hypernatremia causes water movement out of cells, while hyponatremia causes water movement into cells, resulting in cellular shrinkage and cellular swelling, respectively. Serious central nervous system symptoms may complicate both conditions. Since hypernatremia and hyponatremia are accompanied by abnormalities in water balance, it is essential to understand the mechanisms regulating extracellular osmolality and volume as well as the pathophysiology of hypernatremia and hyponatremia, in order to manage both conditions with swiftness and safety.