• Journal of Korean Society for Atmospheric Environment
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• v.14 no.5
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• pp.499-506
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• 1998

Recently almost wastes except recycled garbage are dumped into landfill site in Korea. Landfills are significant compounds (NMOCS) are produced. NMOCS include reactive volative organic compound (VOC) and hazardous air pollutants. LAEEM (Landfill Air Emissions Estimation Model) developed by Control Technology Center, V.S. EPA is used to estimate a mount of landfill gas from all landfills. As the result, landfill gas 4,121,000 ton, carbon dioxide 2,951,000 ton, methane 1,1120,000 ton are estimated as emissions from all landfills in Korea.

• Bulletin of the Korean Mathematical Society
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• v.42 no.4
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• pp.671-678
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• 2005

Let R be a noncommutative semi prime ring. Suppose that there exists a derivation d : R $\to$ R such that for all x $\in$ R, either [[d(x),x], d(x)] = 0 or $\langle$$\langle(x),\;x\rangle,\;d(x)\rangle$ = 0. In this case [d(x), x] is nilpotent for all x $\in$ R. We also apply the above results to a Banach algebra theory.

• Journal of the Korean Mathematical Society
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• v.47 no.4
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• pp.805-818
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• 2010

We classify linear maps which preserve idempotents on $n{\times}n$ matrices over some classes of semirings. Our results include many known semirings like the semiring of all nonnegative integers, the semiring of all nonnegative reals, any unital commutative ring, which is zero divisor free and of characteristic not two (not necessarily a principal ideal domain), and the ring of integers modulo m, where m is a product of distinct odd primes.

• Mycobiology
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• v.30 no.4
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• pp.219-224
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• 2002

Growth studies of Catenaria anguillulae isolates in response to sodium chloride indicated that all the isolates grew in linseed oil-cake agar medium containing sodium chloride up to 1.0%. Medium with 1.5% sodium chloride, however, completely checked the growth of all the isolates. The size of zoosporangia greatly increased with abundant zoospore production in medium containing sodium chloride at 0.5%.

• Honam Mathematical Journal
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• v.35 no.4
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• pp.775-791
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• 2013

The twisted torus knots and the primitive/Seifert knots both lie on a genus 2 Heegaard surface of $S^3$. In [5], J. Dean used the twisted torus knots to provide an abundance of examples of primitive/Seifert knots. Also he showed that not all twisted torus knots are primitive/Seifert knots. In this paper, we study the other inclusion. In other words, it shows that not all primitive/Seifert knots are twisted torus knot position. In fact, we give infinitely many primitive/Seifert knots that are not twisted torus knot position.

• Mycobiology
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• v.29 no.4
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• pp.190-193
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• 2001

Four strains of Phellinus spp. was identified based on internal transcribed spacer(ITS) region of rDNA sequence analysis and morphological characteristics. Basidiocarps of all strains were effused-reflexed and hymenial surface was poroid. Hyphal system was dimitic and basidiospore was globose to ellipsoid. The amplification of ITS regions produced a DNA fragment of 500 to 780 by in all strains examined. The determined sequences were analyzed for the reconstruction of phylogenetic tree. From these results, Phellinus sp. KM-1, KM-2, and KM-4 was identified as P. hartigii, P. baumii, and P. linteus, respectively.

• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.423-426
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• 2006

Distance relays achieve selective tripping by measurement of all short circuit fault conditions inside set reaches. The direction of the fault, forward or reverse is commonly determined with a dedicated measurement to ensure selectivity under all conditions. For the direction decision (measurement) a number of alternatives are available. This paper describes a loop selective direction measurement and illustrates by means of a typical fault why this is superior to a non loop selective direction measurement such as that based on negative sequence quantities.

• Journal of Chest Surgery
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• v.5 no.2
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• pp.147-152
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• 1972

This is a report on the 4 cases of benign mediastinal teratoid tumor in the Department of Thoracic Surgery Chonnam University Hospital during the period from August, 1961 to August ,1972. All the tumors were teratomas which had three germinal layers and located in the anterior mediastinum. All the cases had symptoms such as Pancoast syndrome. exertional dyspnea, middle lobe syndrome with fistulous Connection to the cyst and retrosternal discomfort. X-ray studies are essential to recognize the tumor and its location. It`s believed that a exploratory thoracotomy is recommended because of the complications of the tumors and a possibility of malignancy.

• Korean Journal of Applied Biomechanics
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• v.30 no.4
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• pp.301-309
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• 2020

Objective: This study aimed to investigate the effect of white noise on dynamic balance in patients with stroke during walking. Method: Nineteen patients with chronic stroke (age: 61.2±9.8 years, height: 164.4±7.4 cm, weight: 61.1±9.4 kg, paretic side (R/L): 11/8, duration: 11.6±4.9 years) were included as study participants. Auditory stimulus used white noise, and all participants listened for 40 minutes mixing six types of natural sounds with random sounds. The dynamic balancing ability was evaluated while all participants walked before and after listening to white noise. The variables were the center of pressure (CoP), the center of mass (CoM), CoP-CoM inclined angle. Results: There is a significant increase in the antero-posterior (A-P) CoP range, A-P inclination angle, and gait speed on the paretic and non-paretic sides following white noise intervention (p<.05). Conclusion: Our findings confirmed the positive effect of using white noise as auditory stimulus through a more objective and quantitative assessment using CoP-CoM inclination angle as an evaluation indicator for assessing dynamic balance in patients with chronic stroke. The A-P and M-L inclination angle can be employed as a useful indicator for evaluating other exercise programs and intervention methods for functional enhancement of patients with chronic stroke in terms of their effects on dynamic balance and effectiveness.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.182-192
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• 2022

This study analyzed the effects of the all-in-one automatic fire shutter (hereinafter referred to as "all-in-one shutter") installed along the fire compartment in a five-story high school building on the evacuation time by using the Pathfinder simulation program. When the all-in-one shutter was added as a new variable, the evacuation time was delayed, indicating insufficient evacuation safety. The evacuation time exceeded the appropriate standard when the evacuation exit was designated to the students in the present state of being placed on the 2nd, 3rd, and 4th floors and the all-in-one shutter was activated. When students were placed on the 1st, 2nd and 3rd floors under the same conditions, the evacuation time was also greatly exceeded. However, when the width of the entrance was set to 130cm, the evacuation time was almost the same as when the all-in-one shutter was not installed. In high-rise school buildings, the bottleneck caused by all-in-one shutters is becoming a major factor in evacuation barriers. To ensure the evacuation safety of school buildings, it has been judged that evacuation education and training to predict the evacuation time required through the all-in-one shutter entrance and induce an evacuation procedure suitable for the standard evacuation time should be carried out in parallel. The implications of this study and suggestions for effective fire compartments and follow-up studies were discussed.