• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.2
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• pp.251-259
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• 2000

The ionic wind formed in a nonuniform electric field has been recognized to have a significant effect on particle collection in an electrostatic precipitator(ESP). Under normal operating conditions the effect of ionic wind is not pronounced. However, as the flow velocity becomes smaller, the ionic wind becomes pronounced and induces secondary flow, which has a significant influence on the flow field and the particle collecting efficiency. In this paper, experiments for investigating the effect of secondary flow on collection efficiencies were carried out by changing the flow velocities in 0.2-0.7m/s and the applied voltages in 9-11kV/cm. The particle size distributions and concentrations are measured by DMA and CNC. To analyze the experimental results, numerical analysis of electric filed in ESP was carried out. It shows that particle collection is influenced by two independent dimensionless numbers, $Re_{ehd}\;and\;Re_{flow}$ not by $N_{ehd}$ alone. When $Re_{flow}$, decreases for constant $Re_{ehd}$, the secondary flow prohibits the particle collection. But when $Re_{ehd}$ increases for constant $Re_{flow}$, it enhances the particle collection by driving the particles into the collection region.

• Korean Business Review
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• v.12
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• pp.139-159
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• 1999

The merger of companies makes it easily that a company get over the limitation of the growth of their internal size. A company can attain its purpose, the growth of itself, merging of existing company. On December 1986, "The Accounting Standards for Business Combinations" were pronounced in Korea. But, some of contents of the standards contain many problems criticized in accounting. The purpose of paper is to examine all kinds of affairs problems resulting from merger in Korea and to present the solutions for the problems. I have reexamined the method and provision of on 1999, "The Accounting Standards for Business Combinations" were pronounced in Korea and developed to the direction of trying to deal with tax affairs reasonably. Next, related to current tax system regarding merger, I have described, centered on tax laws, basic rules and the provisions of taxation on merger corporation and the provision of taxation on shareholders at the time of merger.

• Phonetics and Speech Sciences
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• v.3 no.2
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• pp.11-22
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• 2011

The purpose of this study is to find the influence of Chinese falling-rising tone on the pitch pattern of corresponding Sino-Korean words delivered by Chinese learners of Korean and to examine how the falling-rising tone of corresponding Chinese words affect the pitch patterns of Sino-Korean words. The scope of this research is limited to Chinese learners of Korean, especially when they pronounce same-form-same-meaning Sino-Korean words. In this study, Chinese learners pronounced both Chinese words and corresponding Sino-Korean words. Learners' pitch patterns were recorded and analyzed using software and compared with the tone of corresponding Chinese words. Experimental results showed that Sino-Korean words were affected by Chinese 'falling-rising tone - high and level tone' when they started with lenis sounds. On the other hand, when Sino-Korean words started with aspirated sounds they were affected by Chinese 'falling-rising tone - high and level tone', 'falling-rising tone - falling-rising tone', and 'falling-rising tone - falling tone'. In conclusion, the Chinese learners' pitch patterns of Sino-Korean words are affected by Chinese falling-rising tone, especially when Sino-Korean words start with aspirated sounds.

• The Journal of the Acoustical Society of Korea
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• v.14 no.1
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• pp.56-64
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• 1995

In this paper we extracted control rules of synthetical pauses and syllable durations depending on pronunciation speed in Korean speech from the spoken sentences recorded by 18 professional announcers. Pause rules were divided into three categories : pause between sentences(PBS), pause between clauses(PBC) and pause between intonational phrases(PBI). From the analysis results it is found that comparing the slowly spoken sentence with the fast spoken sentence the duration difference between them is due to the synthetical pause increments, expecially, of PBS and PBC. In addition, it is also found that the increment ratio of the mean syllable duration Is low. On the other hand, PBI was not pronounced in the fast spoken sentences. PBI was pronounced at the pronunciation speed(PS) over some PS.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.165-165
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• 2000

In the phoneme level, English stop sounds are classified with the feature of 'voicing': voiceless and voiced (p/b, t/d, k/g). But when realized, a voiceless stop is not alwats the same sound. For example, the two 'p' sounds in 'people' are different. The former is pronounced with much aspiration, while the latter without it. This allophonic differnece between [$P^h$] and [p] out of an English phoneme /p/ can be well explained to Koreans because in Korean these two sounds exist as two different phonemes {/ㅍ/ and /ㅃ/ respectively). But difficulties lie in teaching the English voiced stop sounds (/b, d, g/) to Koreans because in Korean voiced stops do not exist as phonemes but as allophones of lenis sounds (/ㅂ, ㄷ, ㄱ/). For example, the narrow transcription of '바보' (a fool) is [baboo]. In the word initial position, Korean lenis stops are pronounced voiceless and even with a slight aspiration while in the inrervocalic environments they become voiced, That is in Korean voiced stops do not occur independently and neither they have their own letters. To explain all these more effectively to Koreans, it is very helpful to use Korean Phenetic Alphabet (KPA) which is devised by Dr. LEE Hyunbok (a professor of phonetics at Seoul National Univ. and chairman of Phonetic Society of Koera.)(omitted)

• 한국지구물리탐사학회:학술대회논문집
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• 2007.12a
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• pp.73-83
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• 2007

We interpreted marine seismic profiles in conjunction with swath bathymetric and magnetic data to investigate rifting to breakup processes at the eastern Korean margin that led to the separation of the southwestern Japan Arc. Analysis of rift fault patterns suggests that rifting at the Korean margin was primarily controlled by normal faulting resulting from extension rather than strike-slip deformation. Two extension directions of E-W and NW-SE for rifting are recognized. We interpret that the E-W direction represents initial rifting at the inner margin and the NW-SE direction probably represents the extension in response to tensional tectonics associated with the subduction of the Pacific Plate in the NW direction. No significant volcanism was involved in rifting. In contrast, the inception of sea floor spreading documents a pronounced volcanic phase which appears to reflect asthenospheric upwelling as well as rift-induced convection particularly in the narrow southern margin. We suggest that structural and igneous evolution of the Korean margin, although it is in a back-arc setting, can be explained by the processes occurring at the passive continental margin with magmatism influenced by asthenospheric upwelling.

• Journal of Korea Foundry Society
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• v.28 no.6
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• pp.273-281
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• 2008

Effects of alloying elements on the mechanical properties of hardened and austempered 3.60wt%C - 2.50wt%C ductile cast iron were investigated. Strength and hardness were increased and ductility was decreased as the amount of alloying element increased. The increasing effect of copper addition on the strength was the most pronounced. The strength and hardness were greatly increased and ductility was decreased by hardening. The effect of alloying element on the mechanical properties of the hardened ductile cast iron was not so pronounced due to the high contents of C and Si. The strength and hardness of austempered ductile cast iron were greatly increased, meanwhile the difference of strength from that of hardened one was not so big. The ductility of the former was higher than that of the latter. The strength and ductility of austempered ductile cast iron with 0.25%Mn were the maximum of all Mn added ones. The maximum strength of that was obtained with the addition of 0.80wt%Cu or 2.00wt%Ni along with this amount of Mn added.

• Speech Sciences
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• v.8 no.4
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• pp.171-184
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• 2001

American English vowels and Korean vowels were compared by the plotformant method. For American English vowels, six General American English speakers pronounced English words in the b_t environment. For Korean vowels eight Kyongsang dialect speakers and eight Seoul dialect speakers pronounced Korean words in the environments of k_t, p_t and t_t. The formant plots were obtained by plotting F1/F2 tokens of 13 American English vowels on the F1xF2 plane. In spite of personal variations the 13 vowel spaces of all six American English speakers maintained their relative positions with some overlaps. Clear distinctions were made between i-I, e-$\varepsilon$, u-$\sigma$, and o-c. The domain of c and $\alpha$ overlapped for three American English speakers, but it did not for three other speakers. The 8 Korean vowel spaces of Kyongsang dialect speakers and Seoul dialect speakers were very similar and maintained their relative positions. No distinction was made between e and $\varepsilon$. In contrast with American English e which is a neutral vowel, Korean e was a back vowel. The comparison of 13 American English vowel positions and 8 Korean Vowel positions is expected to shed some light on the errors of English vowel pronunciation of Korean learners.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.67.3-68
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• 2016

We present evidence of the bar driven secular evolution on disks from z~0.8 to z~0.01. Using $3.6{\mu}m$ images of nearby galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G) and images from the Cosmological Evolution Survey (COSMOS), we find that barred galaxies show a light deficit in the disk surrounding the bar within the bar radius. We quantify this light deficit and find that galaxies with a stronger bar (longer, higher Bar/T) show a more pronounced light deficit. We examine snapshots from N-body simulations and confirm that as a barred galaxy evolves, the bar becomes longer and the light deficit becomes more pronounced. Theoretical studies have predicted that bars evolve by capturing nearby disk stars and employing them to make the bar more elongated and stronger. Therefore the light deficit in the disk is likely produced by bars, and thus bars play a major role in shaping their host galaxies, redistributing not only the gaseous but also the stellar mass within galaxies, with important consequences to their subsequent evolution.

• YAKHAK HOEJI
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• v.22 no.4
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• pp.201-206
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• 1978

The analysis of elemental sulfur by polarography has already been reported in the literature. Only a discussion of the more important factors influencing the analysis is here presented. (1) The effects of pH on the reduction of elemental sulfur are pronounced and the use of buffered solutions for the analysis of elemental sulfur is necessary. The authors found that a pH of 4-6 was found to be reproducible polarograms by use of D.C. polarograph. However, in alkali solvents the plateau of elemental sulfur has a pronounced dip if the concentration of sulfur is as much as 30ppm. (2) A.C. polarographic method shows a very high sensitivity in the case of sulfur reduction, so that the very low concentration of sulfur can easily be determined (about 1ppm). (3) The characteristics of sulfur wave can be formulated according to Stackelberg-Hauck-Hans equation. It was found that the curve of the peak potential of elemental sulfur in A.C. polarography versus logarithm of sulfur concentration was obtained to be straight line with the slope of 29.6 millivolts. This result was well agreed with theoretical consideration. (4) It was assumed that this polarographical methods were applicable to micro-analysis of elemental sulfur in crude oil and its petrochemical products, precipitated sulfur, and sulfur ointments with accuracy and rapidity.