• Korean Journal of Remote Sensing
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• v.20 no.1
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• pp.57-64
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• 2004

In GIS-based network analysis, topological measure of network structure can be considered as one of important factors in the urban transportation analysis. Related to this measure, it is known that the connectivity indices such as alpha index and gamma index, which mean degree of network connectivity and complexity on a graph or a circuit, provide fundamental information. On the other hand, shimbel index is one of GIS-based spatial metrics to characterize degree of network concentration. However, the approach using these quantitative indices has not been widely used in practical level yet. In this study, an application program, in complied as extension, running on ArcView- GIS is implemented and demonstrated case examples using basic layers such as road centerline and administrative boundary. In this approach, geo-spatial imagery can be effectively used to actual applications to determine the analysis zone, which is composed of networks to extract these indices. As the results of the implementation and the case examples, it is notified that alpha and gamma indices as well as shimbel index can be used as referential data or auxiliary information for urban planning and transportation planning.

• Earthquakes and Structures
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• v.17 no.5
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• pp.477-487
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• 2019

Understanding the behavior of skew bridges under the action of earthquakes is quite challenging due to the combined transverse and longitudinal responses even under unidirectional hit. The main goal of this research is to assess the response of skew bridges when subjected to longitudinal and transversal earthquake loading. The effect of skew on the response considering two- and three- span bridges with skew angles varying from 0 to 60 degrees is illustrated. Various pier fixities (and hence stiffness) and cross-section shapes, as well as different abutment's bearing articulations, are also studied. Finite-element models are established for modal and seismic analyses. Around 900 models are analyzed under the action of the code design response spectrum. $Vis-{\grave{a}}-vis$ modal properties, the higher the skew angle, the less the fundamental period. In addition, it is found that bridges with skew angles less than 30 degrees can be treated as straight bridges for the purpose of calculating modal mass participation factors. Other monitored results are bearings' reactions at abutments, shear and torsion demand in piers, as well as deck longitudinal displacement. Unlike straight bridges, it has been typically noted that skew bridges experience non-negligible torsion and bi-directional pier base shears. In a complementary effort to assess the accuracy of the conducted response spectrum analysis, a series of time-history analyses are applied under seven actual earthquake records scaled to match the code design response spectrum and critical comparisons are performed.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.218-218
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• 2015

Urbanization and waterworks construction in natural watershed have been causing higher flood risks in lowland areas. Detention basins have become one of the most efficient fundamental instruments for storm water and environmental management at watershed scale. Nowadays, there are many studies coupled numerical methods of flood routing with optimization algorithms to investigate factors that impact on the efficiency of detention basins in flood reduction in a watershed, such as detention basin location, size, and cost and watershed characteristics. Although these couplings have been become more widespread but cumbersome computation and hydraulic data requirement still are their limitations. To tackle the procedure efforts due to numerical integration and data collection, simple approach is proposed to primarily estimate effects of detention basins. The approach basis is the linear system theory applied to the solution of hydrologic flood routing. The paper introduces an analytical method for estimating detention effects deriving by recent studies and innovatively analyses this equation on fractal perspective. Then, an optimization technique is performed by applying harmony search algorithms (HSA) to optimize efficiency of detention basins at watershed scale. The location and size of upstream detention basin are simultaneously obtained. Finally, the proposed methodology, practically applied for a real watershed in Kan river, Iran.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.349-354
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• 2019

Workers who die from falls at construction sites account for about 40 percent of the total number of deaths and are the main forms of accidents. In addition, as the nation's population structure is gradually aging, the rate of aging is increasing at construction sites, and the number of crashes due to decreased physical function and cognitive ability is increasing. Accordingly, we conducted a survey on the factors affecting the fall of older workers and would like to present more fundamental measures to prevent falls, focusing on older workers who are the victims of the disaster.

• Earthquakes and Structures
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• v.9 no.2
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• pp.339-352
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• 2015

Ancient masonry towers constitute a relevant part of the cultural heritage of humanity. Their earthquake protection is a topic of great concern among researchers due to the strong damage suffered by these brittle and massive structures through the history. The identification of the seismic behavior and failure of towers under seismic loading is complex. This strongly depends on many factors such as soil characteristics, geometry, mechanical properties of masonry and heavy mass, as well as the earthquake frequency content. A deep understanding of these aspects is the key for the correct seismic vulnerability evaluation of towers and to design the most suitable retrofitting measure. Recent tendencies on the seismic retrofitting of historical structures by means of prestressing are related to the use of smart materials. The most famous cases of application of prestressing in towers were discussed. Compared to horizontal prestressing, vertical post-tensioning is aimed at improving the seismic behavior of towers by reducing damage with the application of an overall distribution of compressive stresses at key locations.

• Computers and Concrete
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• v.18 no.2
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• pp.235-266
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• 2016

A rock mass containing non-persistent joints can only fail if the joints propagate and coalesce through an intact rock bridge. Shear strength of rock mass containing non-persistent joints is highly affected by the both, mechanical behavior and geometrical configuration of non-persistent joints located in a rock mass. Existence of rock joints and rock bridges are the most important factors complicating mechanical responses of a rock mass to stress loading. The joint-bridge interaction and bridge failure dominates mechanical behavior of jointed rock masses and the stability of rock excavations. The purpose of this review paper is to present techniques, progresses and the likely future development directions in experimental and numerical modelling of a non-persistent joint failure behaviour. Such investigation is essential to study the fundamental failures occurring in a rock bridge, for assessing anticipated and actual performances of the structures built on or in rock masses. This paper is divided into two sections. In the first part, experimental investigations have been represented followed by a summarized numerical modelling. Experimental results showed failure mechanism of a rock bridge under different loading conditions. Also effects of the number of non-persistent joints, angle between joint and a rock bridge, lengths of the rock bridge and the joint were investigated on the rock bridge failure behaviour. Numerical simulation results are used to validate experimental outputs.

• Journal of Korean Medicine for Obesity Research
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• v.3 no.1
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• pp.95-105
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• 2003

The obesity is the matter of the energy balance in essential. The energy balance in human body is energy expenditure subtracted from energy intake. The energy intake is mainly supplied by carbohydrates, proteins and lipids in food, and the energy expenditure is composed of basal metabolic rate or resting energy expenditure, physical activity and thermogenesis including diet-induced thermogenesis. The resting energy expenditure is measured by direct calorimetry and indirect calorimetry. Generally we can simply use predictive equation with the variables of weight, height, age and fat-free mass to yield metabolic rate. But there is discrepancy between the estimate and real metabolic rate because the equations can not reflect individuality and environments. The resting energy expenditure is influenced by many factors but the fundamental factor is fat-free mass. We briefly reviewed the concept and evaluation of the energy balance, intake and expenditure, which are important parts in the study of obesity. Finally, we surveyed the correlation between metabolic rate and obesity and suggested applicable herb medication to increase metabolic rate.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.391-397
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• 2021

One of the sustainable development goals is to promote good health and well-being for all people. Child health is a top priority since their health issues can have a detrimental impact on human capital development, which is a critical input for the growth model. This paper applies the health production model to explore the determinants that influence the health of children under the age of five. The results of a survey of 203 households in Ho Chi Minh City, Vietnam, were examined. Child health is measured using anthropometric indicators such as weight-for-age, height-for-age, and weight-for-height (ZWFH). Three separate multinomial logistic models are regressed to examine the drivers of child health as proxied by z-score weight for age, z-score height for age, and z-score weight for height. The significance of input variables relating to a child's attributes, household, and environment was validated by the findings. The inclusion of overweight besides under-nourished indexes is novel because it reflects the current trend of child over-nutrition. The findings of the study highlight the importance of a wide range of initiatives to enhance child health. Moreover, the genetic effect is found to be crowded out by environmental and household factors. The finding verifies that despite their parents' moderate height, the future generation of Vietnamese can achieve the desired height.

• Journal of the Korean Medical Association
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• v.61 no.12
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• pp.749-755
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• 2018

Particulate matter is an air pollutant emitted from both natural and anthropogenic sources, and its adverse health effects have been well documented in time-series analyses and cohort studies. The effect size of particulate matter exposure-a roughly 0.5% increase in mortality for each $10{\mu}g/m^3$ increment of short-term exposure to particulate matter with aerodynamic diameter ${\leq}10{\mu}m$ and approximately a 10% increase for each $10{\mu}g/m^3$ increment of long-term exposure to particulate matter with aerodynamic diameter ${\leq}2.5{\mu}m$-is small compared to other risk factors, but the exposure is involuntary and affects the entire population, which makes particulate matter pollution an important public health issue. The World Health Organization and Korean government have both established guidelines for particulate matter concentrations, but the Korean guideline is less stringent than that of the World Health Organization. The annual mean concentration of particulate matter in Korea is decreasing, but the trend seems to be slowing. In addition to policy efforts to reduce particulate matter emission, personal approaches such as the use of face masks and air purifiers have been recommended. Personal approaches may not solve the fundamental problem, but can provide temporary mitigation until efforts to reduce emission make progress.

• Journal of Korean Neurosurgical Society
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• v.62 no.3
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• pp.272-287
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• 2019

The mechanistic target of rapamycin (mTOR) pathway coordinates the metabolic activity of eukaryotic cells through environmental signals, including nutrients, energy, growth factors, and oxygen. In the nervous system, the mTOR pathway regulates fundamental biological processes associated with neural development and neurodegeneration. Intriguingly, genes that constitute the mTOR pathway have been found to be germline and somatic mutation from patients with various epileptic disorders. Hyperactivation of the mTOR pathway due to said mutations has garnered increasing attention as culprits of these conditions : somatic mutations, in particular, in epileptic foci have recently been identified as a major genetic cause of intractable focal epilepsy, such as focal cortical dysplasia. Meanwhile, epilepsy models with aberrant activation of the mTOR pathway have helped elucidate the role of the mTOR pathway in epileptogenesis, and evidence from epilepsy models of human mutations recapitulating the features of epileptic patients has indicated that mTOR inhibitors may be of use in treating epilepsy associated with mutations in mTOR pathway genes. Here, we review recent advances in the molecular and genetic understanding of mTOR signaling in epileptic disorders. In particular, we focus on the development of and limitations to therapies targeting the mTOR pathway to treat epileptic seizures. We also discuss future perspectives on mTOR inhibition therapies and special diagnostic methods for intractable epilepsies caused by brain somatic mutations.