• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.8-8
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• 2019

The stringent response (SR) is characterized as a bacterial defense mechanism in response to various growth-inhibiting stresses. It is activated by accumulation of a small nucleotide regulator, (p)ppGpp, and induces global changes in bacterial transcription and translation. Recent work from our group has shown that (p)ppGpp plays a critical role in virulence and survival in Vibrio cholerae. The genes, relA and relV, are involved in the production of (p)ppGpp, while the spoT gene encodes an enzyme that hydrolyzes it in V. cholerae. A mutant strain defective in (p)ppGpp production (i.e. ${\Delta}relA{\Delta}relV{\Delta}spoT$ mutant) lost the ability to produce cholera toxin (CT) and lost their viability due to uncontrolled production of organic acids, when grown with extra glucose. In contrast, the ${\Delta}relA{\Delta}spoT$ mutant, a (p)ppGpp overproducer strain, produced enhanced level of CT and exhibited better growth in glucose supplemented media via glucose metabolic switch from organic fermentation to acetoin, a neutral fermentation end product, fermentation. These findings indicates that (p)ppGpp, in addition to its well-known role as a SR mediator, positively regulates CT production and maintenance of growth fitness in V. cholerae. This implicates SR as a promising drug target, inhibition of which may possibly downregulate V. cholerae virulence and survival fitness. Therefore, we screened a chemical library and identified a compound that induces medium acidification (termed iMAC) and thereby loss of wild type V. cholerae viability under glucose-rich conditions. Further, we present a potential mechanism by which the compound inhibits (p)ppGpp accumulation. Together, these results indicate that iMAC treatment causes V. cholerae cells to produce significantly less (p)ppGpp, an important regulator of the bacterial virulence and survival response, and further suggesting that it has a therapeutic potential to be developed as a novel antibacterial agent against cholera.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.4
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• pp.103-111
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• 2018

The Soswaewon Garden, which was constructed by Yang San-Bo around 1520, is a private traditional garden in Korea. Soswaewon Garden has long been and still is the focus of continuous research. However, relatively few studies have been conducted on the restoration of buildings that were lost in the past. The Goam-Jeongsa and Boohwondang buildings, which were lost in 1597 during the Japanese invasion, were restored in 1614 and depicted in a picture of Soswaewon Garden in 1755. However, they eventually disappeared and no longer exist in the present. Therefore, the restoration of these two buildings is considered an urgent task. This research aims to search for the original location of these buildings and estimate their size and shape in terms of physical space. Several years ago, an estimation of the building site was carried out, providing a stepping stone on this matter. This can be studied through "Soswaewon's 48 quatrains with five Chinese characters in each line," "Soswaewon-sasil," and "Soswaewon's drawing." Some parts of the shape of Soswaewon also appear in the "Yuseoseokrok," which is helpful. Thus, in this research, information on the Goam-Jeongsa and Boowondang buildings appearing in research results and literature to date are collectively analyzed. The location and architectural features of both buildings are identified by focusing on excavations. Also, for the purpose of restoration planning, base data on the location, size, and shape of both buildings are presented. In line with this process, a valid restoration plan is presented by analyzing the abovementioned historical research materials and comparing empirical data, such as excavation results.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.9
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• pp.87-96
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• 2018

The purpose of this study is to get a more fundamental definition of the term Architecture and Geonchuk through analyzing the origin and reception of the terminus technicus Architektonike. In Latin world the greek term Architektonike was adopted and replaced the term Constructio by Vitruvius and has played a significant role in the history of architecture. In the late 19th Century however, the word Architecture was translated into Geonchuk(建築) and has been dominantly used in countries such as Korea, Japan, and China. But the difference of the denotation between them has not yet been fully evaluated. The term Geonchuk signifies much the same as the Tektonik and remains as such in the architectural discourse. In this context, this study goes back to refer to the philosophy of Metaphysics by Aristotle. In his book the term Architektonike was defined for the first time as terminus technicus, and the philosophies in later Ages of Leibniz or of Kant adopted it to signify the world view in accordance with the time. However, the original thought of the Architektonike disappeared in architectural practice and has been used in most cases as a substitute for Oikodomike which denotes house-building. The usage of this word in later time shows that it lost its foundation to be interpreted not only in terms of principium cognoscendi, but also in terms of principium reale. From this the literal usage of the term architecture and Geonchuk has seldom to do with its original meaning and denotation of Architektonike and also they lost the status of terminus technicus for the discourse of arche which encompasses the meaning of both principle and universal order.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.1
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• pp.49-60
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• 2020

Although the number of child loss in commercial facilities has been growing recently, the prevention method for child loss are still lacking in the environmental aspect. This research examines the causes of lost child in behavioral aspects in order to develop a guideline to prevent child loss in U.E.C. The observational study on the behaviors of guardians and children was conducted in the U.E.C that is visited by many customers accompanied with children. Then the results of the observational study were marked on the behavioral maps. After analyzing the behavioral maps, the causes of child loss were determined by classifying into behaviors by age and behaviors by functional space. As a result, when guardian is unable to pay attention to child by doing something else such as making a purchase, or an inquiry, child may lose guardian by going towards the interesting factors or playing around. Moreover, if the spaces related to children are located at the node with high pedestrian density and open structure or the environment that is hard for the guardians to watch over their children, it will be easy for guardians to be inattentive to their children, and get separated from each other.

• Journal of the Korea Convergence Society
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• v.12 no.2
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• pp.7-13
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• 2021

This paper introduces an algorithm that compensates for missing values after converting them into a format that can represent the probability for incomplete data including missing values in training data. In the previous method using this data conversion, incomplete data was processed by allocating missing values with an equal probability that missing variables can have. This method applied to many problems and obtained good results, but it was pointed out that there is a loss of information in that all information remaining in the missing variable is ignored and a new value is assigned. On the other hand, in the new proposed method, only complete information not including missing values is input into the well-known classification algorithm (C4.5), and the decision tree is constructed during learning. Then, the probability of the missing value is obtained from this decision tree and assigned as an estimated value of the missing variable. That is, some lost information is recovered using a lot of information that has not been lost from incomplete learning data.

• Korean Journal of Metals and Materials
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• v.47 no.7
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• pp.440-446
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• 2009

Co base superalloys have been widely used for the parts of gas turbine due to their excellent strength, thermal fatigue, oxidation resistance and weldability at high temperature. In this study, directional solidifications were carried out at various solidification rates, including $0.5{\sim}300{\mu}m/s$ in the Co base superalloy FSX-414. The cellular interface were formed at a low solidification rate, $1{\mu}m/s$, and the dendritic interface was found at higher solidification rates, $5{\sim}300{\mu}m/s$. As the spacing of dendrite structure decreased, the size and spacing of eutectics decreased. Dendrite arm spacing decreased with increasing solidification rates and temperature gradient. It was interesting to find the $M_{23}C_{6}$ eutectic microstructure formed between $\gamma$ dendrites. Composition analysis showed that Cr and W were segregated severely between the dendrites, which resulted in the formation of Cr-rich $M_{23}C_{6}$ and W-rich MC carbides.

• Korean Journal of Metals and Materials
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• v.49 no.1
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• pp.58-63
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• 2011

The grain size and growth direction of a directionally solidified turbine blade were evaluated by the initial nucleation condition at the start block of directional solidification. The initial nucleation condition was controlled by inserting a Ni foil on the directional solidification plate of the directional solidification furnace. Fine grains with good orientation were obtained in the faster cooling condition at the start block. The nucleus number was compared with the cooling rate of the start block by electron back scattered diffraction (EBSD). DSC (differential scanning calorimeter) analysis was performed to compare the melting point and undercooling for nucleation of the coarse nuclei and fine nuclei of the start block. The faster cooling condition at the start block showed more undercooling for nucleation and smaller size of nuclei which resulted in a fine grain with good orientation in the directional turbine blade.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.9 no.2
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• pp.83-92
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• 1999

Cryptography techniques can prevent eavesdroppers from maliciously intercepting or modifying sensitive information. however misuses of encryption may cause other problems First if the encryption key is lost or damaged even an authorized access to the original data will be denied. Second criminals can prevent authorized law enforcement officers from examining the necessary information by using the strong encrypted data can provide solutions for the situations. In this paper we propose a new key escrow system based on the ElGamal cryptosystem. Our system provide time-bound eavesdropping under court authorized permission protect from trustee's cheating and prevent user's shadow public key generation.

• Health Policy and Management
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• v.31 no.1
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• pp.100-113
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• 2021

Background: This study aims to figure out the gaps in health status by estimating amenable mortality rate by region, reflecting the characteristics of Korea, and estimating the years of life lost (YLL) per capita by disease. Methods: People who died from amenable diseases between 2008 and 2018 were extracted from the cause of death statistics provided by Statistics Korea. The age-standardized amenable mortality rates were estimated to compare the health status of 229 regions. YLL per capita was calculated to compute the burden of diseases caused by treatable deaths by region. The YLL per capita by region was calculated to identify the burden of disease caused by amenable deaths. Results: First, while the annual amenable mortality rate in Korea is on a steady decline, but there is still a considerable gap between urban and rural areas when comparing the mortality rates of 229 areas. Second, YLL per capita due to the amenable deaths is approximately 14 person-years during the analysis period (2008-2018). Conclusion: Although the health status of Koreans has continuously improved, there is still a gap in health status region by region in terms of amenable mortality rates. Amenable death accounts for a loss of life equivalent to 14 person-years per year. Since the amenable mortality rate is an indicator that can measure the performance of the health care system, efforts at each local area are required to lower it.

• Journal of Preventive Medicine and Public Health
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• v.54 no.2
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• pp.103-109
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• 2021

Objectives: The aim of this study was to calculate the burden of stroke in Kurdistan Province, Iran between 2011 and 2017. Methods: Incidence data extracted from the hospital information system of Kurdistan Province and death data extracted from the system of registration and classification of causes of death were used in a cross-sectional study. The World Health Organization method was used to calculate disability-adjusted life years (DALYs). Results: The burden of stroke increased from 2453.44 DALYs in 2011 to 5269.68 in 2017, the years of life lost increased from 2381.57 in 2011 to 5109.68 in 2017, and the years of healthy life lost due to disability increased from 71.87 in 2011 to 159.99 in 2017. The DALYs of ischaemic stroke exceeded those of haemorrhagic stroke. The burden of disease, new cases, and deaths doubled during the study period. The age-standardised incidence rate of ischaemic stroke and haemorrhagic stroke in 2017 was 21.72 and 20.72 per 100 000 population, respectively. Conclusions: The burden of stroke is increasing in Kurdistan Province. Since health services in Iran are based on treatment, steps are needed to revise the current treatment services for stroke and to improve the quality of services. Policy-makers and managers of the health system need to plan to reduce the known risk factors for stroke in the community. In addition to preventive interventions, efficient and up-to-date interventions are recommended for the rapid diagnosis and treatment of stroke patients in hospitals. Along with therapeutic interventions, preventive interventions can help reduce the stroke burden.