• Korean Journal of Microbiology
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• v.52 no.2
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• pp.166-174
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• 2016

In order to find an efficient bacterial strain that can carry out nitrification and denitrification simultaneously, we isolated many heterotrophic nitrifying bacteria from wastewater treatment plant. One of isolates NS13 showed high removal rate of ammonium and was identified as Alcaligenes faecalis by analysis of its 16S rDNA sequence, carbon source utilization and fatty acids composition. This bacterium could remove over 99% of ammonium in a heterotrophic medium containing 140 mg/L of ammonium at pH 6-9, $25-37^{\circ}C$ and 0-4% of salt concentrations within 2 days. It showed even higher ammonium removal at higher initial ammonium concentration in the medium. A. faecalis NS13 could also reduce nitrate and nitrous oxide by nitrate reductase and nitrous oxide reductase, respectively, which was confirmed by detection of nitrate reductase gene, napA, and nitrous oxide reducase gene, nosZ, by PCR. One of metabolic intermediate of denitrification, $N_2O$ was detected from headspace of bacterial culture. Based on analysis of all nitrogen compounds in the bacterial culture, 42.8% of initial nitrogen seemed to be lost as nitrogen gas, and 46.4% of nitrogen was assimilated into bacterial biomass which can be removed as sludge in treatment processes. This bacterium was speculated to perform heterotrophic nitrification and aerobic denitrification simultaneously, and may be utilized for N removal in wastewater treatment processes.

• Strategy21
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• s.44
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• pp.177-212
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• 2018

The purpose of this article is to examine the 'Discussion of maritime defense' which began to be discussed from the late Goryeo dynasty to the early Joseon dynasty and the process of establishing a maritime defense system. Also it can identify changes in the aspects of the naval ship operation and their strategic tactics during the reign of King Sejong. Japanese raiders began a full-scale invasion from 1350 at the late Goryeo Dynasty, So the government realized the need to raise the 'Sea power' and to organize the maritime defense system for defending enemy invasion. for example, the reinforcement of naval forces, construction of warships, develoment of weapon systems and so on. which have achieved remarkable growth while continuing, have also been used to carry out a three-time 'Conquest of Daemado' in 1389, 1396, 1419. Until then, however, it is difficult to interpret that the naval forces had a systematic and organizational combat operation system. According to fighting patterns on combat reports before the early days of King Sejong's reign, Our naval forces had no advantage over the Japanese raiders in terms of their capabilities and tactics. Then, the period of King Sejong marked a watershed in maritime defense history. Based on accumulated experience of naval battles and force Projections, The paradigm shift of the naval strategic tactics for maritime defense has occurred. First, the capability of the naval vessels has improved. for example, ship speed, durability, and weather resistance. Through these efforts, navy forces were able to pursue and attack, destroy enemy's ships by taking advantage of the 'Ship speed superiority'. This has led to tactical shifts from defensive to offensive. Second, purpose to support offensive tactics, the government put a strategic plan into practice that is the forward depolyment of naval bases from the inland to the coast, considering the 'sea environment' and 'threat'. By doing so, Joseon dynasty was able to secure 'the command of the sea'. This may be a little different from the perception of the so-called 'peace period' that King Sejong's era. We need to remember that Joseon dynasty was working hard for its defense. When studying history of maritime defense, these strategic and tactical elements must be fully considered. Only then we can have a coherent understanding of the many naval battles in the past, including the Imjin War(1592-1598).

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.92-101
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• 2020

To prevent and mitigate damage to farms due to heavy snowfall, snow weight information should be provided in addition to snow depth. This study reviews four formulae regarding snow density and weight used in extant studies and applies them in Suwon area to estimate snow weight in Korea. We investigated the observed snow depth of 94 meteorological stations and automatic weather stations (AWS) data over the past 30 years (1988-2017). Based on the spatial distribution of snow depth by area in Korea, much of the fresh snow cover, due to heavy snowfall, occurred in Jeollabuk-do and Gangwon-do. Record snowfalls occurred in Gyeongsangbuk-do and Gangwon-do. However, the most recent heavy snowfall in winter occurred in Gyeonggi-do, Gyeongsangbuk-do, and Jeollanam-do. This implies that even if the snow depth is high, there is no significant damage unless the snow weight is high. The estimation of snow weight in Suwon area yielded different results based on the calculation method of snow density. In general, high snow depth is associated with heavy snow weight. However, maximum snow weight and maximum snow depth do not necessarily occur on the same day. The result of this study can be utilized to estimate the snow weight at other locations in Korea and to carry out snow weight prediction based on a numerical model. Snow weight information is expected to aid in establishing standards for greenhouse design and to reduce the economic losses incurred by farms.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.2
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• pp.133-144
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• 2006

In order to catch out such Bond Strength, the preceding researchers had ever examined the Bond Strength of FRP Plate through their experimentations by setting up of various fluent. However, since the experiment for research on such Bond Strength takes much of expenditure for equipment structure and time-consuming, also difficult to carry out, it is conducting limitedly. This Study purposes to develop the most suitable Artificial Neural Network Model by application of various Neural Network Model and Algorithm to the adhering experiment data of the preceding researchers. Output Layer of Artificial Neural Network Model, and Input Layer of Bond Strength were performed the learning by selection as the variable of the thickness, width, adhered length, the modulus of elasticity, tensile strength, and the compressive strength of concrete, tensile strength, width, respectively. The developed Artificial Neural Network Model has applied Back-Propagation, and its error was learnt to be converged within the range of 0.001. Besides, the process for generalization has dissolved the problem of Over-Fitting in the way of more generalized method by introduction of Bayesian Technique. The verification on the developed Model was executed by comparison with the resulted value of Bond Strength made by the other preceding researchers which was never been utilized to the learning as yet.

• Journal of Chest Surgery
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• v.32 no.3
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• pp.299-302
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• 1999

Heart transplantation was planned for a 10-year old boy who had dilated cardiomyopathy with severe congestive heart failure and had been on dopamine for 1month. However, partial left ventriculectomy and mitral annuloplasty were performed instead, because there was no donor heart of the adequate size and the symptoms were aggravated. The clinical symptoms were markedly improved after the surgery. Comparing the postoperative echocardiographic results with the preoperative results, there were remarkable changes in the left ventricular ejection fraction(preoperative LV EF 17% to postoperative 3 months 29%, 6 months 35%, 1 year 36%) and the left ventricular end-diastolic dimension(preoperative 72 mm to postoperative 3 months 59 mm, 6 months 61 mm, 1 year 61 mm). Partial left ventriculectomy and mitral annuloplasty reduced the cardiac loading in the dilated cardiomyopathy. Partial left ventriculectomy and mitral annuloplasty may be considered as one of the alternative surgical metho s to carry over until a heart transplantation can be performed, especially for children.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.299-304
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• 2007

There are to be some cracks on the material degradation part or the stress concentration parts of the main members, which carry on over-loads, of structures. Because these cracks can be used to evaluate the structural health status, it is important to monitor the crack growth for maintaining the structural safety. In this study, the fiber Bragg grating sensor with a drop ball was developed as a sensor for crack growth detection of an existing crack. The crack growth detection sensor was constructed with three parts: a probe part, a wavelength controling light source and receiver part, and an impact part. The probe part was just formed with a fiber Bragg grating optical fiber The wavelength controling light source part was composed of a current supplying circuit, a DFB laser diode, and a TEC controling circuit for wavelength control. Also, the impact part was just implemented by dropping a steel ball. The performance of this sensor was confirmed by the experiments of the crack detection with an aluminum plate having one existing crack. According to these experiments, the difference of the sensor signal outputs was correlated with the crack length. So, it was confirmed that this sensor could be applied to monitor the crack growth.

• Korean Journal of Construction Engineering and Management
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• v.21 no.5
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• pp.3-10
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• 2020

Subcontracting of construction is essential to carry out public construction projects. Subcontractor of the construction work shall enter into a contract with the original contractor without directly entering into a contract with the owner. Subcontracts are therefore greatly affected by the original contract with the owner. To protect subcontractors, the Fair Trade Act is enacted and the construction company's standard subcontracting contract is in operation. However, subcontracts are not properly reflected in the Government contract system, which deals with the relationships between the owner and the original contractor. In particular, the subcontractor may complain of difficulties at the public construction site as such procedures are not properly reflected in the construction work standard subcontract, although various procedures shall be carried out depending on the amount when change order occurs in subcontracts. Thus, the direction of improvement of subcontracting systems was proposed in the case of change order at public construction project sites as follows: First, the rights of subcontractors should be strengthened. Second, in order to resolve the information non-identity, subcontractors should have access to information related to subcontracts. Third, the status of subcontractor shall be guaranteed by reflecting the characteristics of the subcontract when the original contract for public works is concluded. Fourth, the dispute settlement method should be prioritized over litigation in order to fair subcontracting.

• Cross-Cultural Studies
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• v.26
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• pp.123-144
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• 2012

In the modern society in which globalization and localization proceed simultaneously, diversified and rapid migration of diaspora makes a new from of boundary off the frame of the state and the nation. This new border accompanies cultural change and racial mixture; retains ethnic conflict, the gap between rich and poor, alienation and discrimination, as well as power conflict; and extends its influence. Nowadays, the countries all over the world including Korea face problem of Diaspora in numerous forms. And each country takes an approach to the problem of the diaspora in the aspects of their society, culture and political technology. This implies that most countries, without understanding the new form of border which is alive and dynamic, define and conceptualize the diaspora in the frame of one state and one nation to carry forward the policies accordingly, resulting in inequal, incomplete and awkward homogenization. This study aimed to explore the identity of the diaspora, the core for the problem solving. Of course, studies about the identity of the diaspora have been continued until today and many great outcomes have been achieved. Nevertheless, this study aimed to explore the identity of the diaspora and the national policies which have a close interrelationship with it. It is because the study ultimately aimed to highlight the interrelationship between the destination countries, Russia and China, and the diaspora, through the definition and the classification of Russian diaspora and Chinese diaspora and the analysis of the national policies about that. However, the intention was not to distinguish superiority through the comparison of the polices about the diaspora between two countries, but to focus on the diversity of the identity of the diaspora through defining each different diaspora and paralleling the policies. Second, the reason for looking into the diaspora policies of these two countries is because it is judged the changes in the diaspora policies of each country is one of the active factors for the changes in the identify of the diaspora of each country and it is the basic research for the study on the identity of the diaspora. New migration of diaspora changes the identity of the state, and the state makes the policies and enforce the policies, resulting in the influence on the diaspora. This interaction acts as the growth factor for the new boundary. The causes of Russian diaspora and Chinese diaspora show apparent 'differences'. In parallel with this, the policies about the diaspora in Russia and China arouse 'differences' to the diaspora. The variation of the identity of the diaspora made by these differences will suggest other viewpoints on the diaspora, and these viewpoints will become the foundation for solving the problem of the diaspora in the present times.

• Journal of Hospice and Palliative Care
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• v.22 no.3
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• pp.125-133
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• 2019

Purpose: The purpose of this study was to investigate the relationship between end of life care competencies and terminal care stress of nurses in long term care hospitals. Methods: For this study, 140 nurses were sampled among those that have over 6-month end of life care experience and were working at long term care hospitals located in A city and C city of Chungcheongnam-do. Using a questionnaire, data were collected from January 2018 through March 2018. Data were analyzed using the SPSS, Windows version 21.0, according to the purpose of the study and analyzed by descriptive statistics, t-test, one way ANOVA, $Sch\acute{e}ffe^{\prime}s$ test, and Pearson's correlation coefficient. Results: The mean score on terminal care stress of nurses was above the normal level. The scores on end of life care competencies significantly varied by age, total career at hospitals, death/hospice and palliative care education, and bereavement experience. The mean score of end of life care competencies was negatively correlated with the mean score of lack of knowledge and skills among the subitems of the terminal care stress category (r=-0.260, P=0.002). Conclusion: To decrease the terminal care stress of long term care hospital nurses, it is suggested to carry out end of life care education tailored to nurses characteristics.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.581-588
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• 2018

The aim of this study is to propose a fine co-registration approach for multi-temporal satellite images acquired from RapidEye, which has an advantage of availability for time-series analysis. To this end, we generate multitemporal ortho-rectified images using RPCs (Rational Polynomial Coefficients) provided with RapidEye images and then perform fine co-registration between the ortho-rectified images. A DEM (Digital Elevation Model) extracted from the digital map was used to generate the ortho-rectified images, and the RNCC (Registration Noise Cross Correlation) was applied to conduct the fine co-registration. Experiments were carried out using 4 RapidEye 1B images obtained from May 2015 to November 2016 over the Yeonggwang area. All 5 bands (blue, green, red, red edge, and near-infrared) that RapidEye provided were used to carry out the fine co-registration to show their possibility of being applicable for the co-registration. Experimental results showed that all the bands of RapidEye images could be co-registered with each other and the geometric alignment between images was qualitatively/quantitatively improved. Especially, it was confirmed that stable registration results were obtained by using the red and red edge bands, irrespective of the seasonal differences in the image acquisition.