• Journal of The Korean Astronomical Society
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• v.37 no.4
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• pp.257-259
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• 2004

We compare the results of the surveys of starless cores performed with CS (2-1) and (3-2) lines to study inward motions in the cores. The velocity shifts of the CS(3-2) and (2-1) lines with respect to $N_2H^+$ are found to correlate well with each other and to have similar number distributions, implying that, in many cores, systematic inward motions of gaseous material may occur over a range of density of at least a factor ${\~}$4. Fits of the CS spectra to a 2-layer radiative transfer model in ten infall candidates suggest that the median effective line-of-sight speed of the inward-moving gas is ${\~}0.07 km\;s^{-l}$ for CS (3-2) and ${\~} 0.04 km\;s^{-l}$ for CS(2-1). Considering that the optical depth obtained from the fits is usually smaller in CS(3-2) than in (2-1) line, this may indicate that CS(3-2) usually traces inner, denser gas with greater inward motions than CS(2-1) implying that many of the infall candidates have faster infall toward the center. However, this conclusion may not be representative of all starless core infall candidates, due to the statistically small number analyzed here. Further line observations will be useful to test this conclusion.

• Journal of information and communication convergence engineering
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• v.11 no.4
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• pp.229-234
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• 2013

Diversity-multiplexing tradeoff (DMT) characterizes the fundamental relationship between the diversity gain in terms of outage probability and the multiplexing gain as the normalized rate parameter r, where the limiting transmission rate is give by rlog SNR (here, SNR denote the received signal-to-noise ratio). In this paper, we analyze the DMT and performance of an underwater network with a cooperative relay. Since over an acoustic channel, the propagation delay is commonly considerably higher than the processing delay, the existing transmission protocols need to be explained accordingly. For this underwater network, we briefly describe two well-known relay transmissions: decode-and-forward (DF) and amplify-and-forward (AF). As our main result, we then show that an instantaneous DF relay scheme achieves the same DMT curve as that of multiple-input single-output channels and thus guarantees the DMT optimality, while using an instantaneous AF relay leads at most only to the DMT for the direct transmission with no cooperation. To validate our analysis, computer simulations are performed in terms of outage probability.

• Journal of Microbiology
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• v.39 no.2
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• pp.133-138
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• 2001

We investigated the antagonism of indigenous bacteria isolated from stressed mussels and their extracellular metabolites on the adult zebra mussel, Dreissena polymorpha. Selective bacterial isolates including Aeromonas media, A. salmonicida, A. veronii, and Shewanella putrefaciens, showed strong lethality against adult mussels and 100% mortality was observed within 5 days of incubation. Bacterial metabolites, fractionated and concentrated from stationary-phase culture supernatants of these bacterial isolates, displayed varying degrees of antagonistic effects on zebra mussels. Among the three size fractions examined, <5, 5-10, and >10 kDa, the mast lethal fraction seems to be >10 kDa for three of the four isolates tested. Further chemical analyses of these size fractions revealed that the predominant constituents were polysaccharides and proteins. No 2-keto-3-deoxyoctanoic acid (2-KDO), deoxyribonucleic acids (DNA) or uranic acid were detectable. Extraction of supernatants of two antagonistic isolates with polar solvent suggested that polar molecules are present in the active fraction. Our data suggest that extracellular metabolites produced by antagonistic bacteria are also involved in disease development in zebra mussels and elucidation of the mechanisms involved may offer a novel strategy for control of biofouling invertebrates.

• Journal of English Language & Literature
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• v.60 no.2
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• pp.193-209
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• 2014

Writers in England's colonies and former colonies have long struggled with the advantages and disadvantages of employing the language of the colonizer for their creative work, an issue that today reaches beyond the older imperial trade routes in the era of "global English." Creative writers in widely disparate locations are now using global English to their advantage, with what can be described as post-postcolonial strategies. This essay explores the politics of global English, beginning with a satiric dictionary of "Strine" (Australian English) from 1965, and then looking back at the mid-1960s debate at Makerere University between Ngugi wa Thiong'o and Chinua Achebe, in which Achebe famously asserted the importance of remaking English for hi own purposes. The essay then discusses early linguistic experiments by Rudyard Kipling, who became the world's first truly global writer in the 1880s and 1890s and developed a range of strategies for conveying local experience to a global audience. The essay then turns to two contemporary examples: a comic pastiche of Kipling-and of Kiplingese-by the contemporary Tibetan writer Jamyang Norbu, who deploys "Babu English" and the legacy of British rule against Chinese encroachment in Tibet; and, finally, the Korean-American internet group Young-hae Chang Heavy Industries, who interweave African-American English with North Korean political rhetoric to hilariously subversive effect.

• The Korean Journal of Pain
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• v.34 no.3
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• pp.346-368
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• 2021

Background: Recalcitrant disc herniation may result in chronic lumbar radiculopathy or sciatica. Fluoroscopically directed epidural injections and other conservative modalities may provide inadequate improvement in some patients. In these cases, percutaneous neurolysis with targeted delivery of medications is often the next step in pain management. Methods: An evidence-based system of methodologic assessment, namely, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used. Multiple databases were searched from 1966 to January 2021. Principles of the best evidence synthesis were incorporated into qualitative evidence synthesis. The primary outcome measure was the proportion of patients with significant pain relief and functional improvement (≥ 50%). Duration of relief was categorized as short-term (< 6 months) and long-term (≥ 6 months). Results: This assessment identified one high-quality randomized controlled trial (RCT) and 5 moderate-quality non-randomized studies with an application of percutaneous neurolysis in disc herniation. Overall, the results were positive, with level II evidence. Conclusions: Based on the present systematic review, with one RCT and 5 non-randomized studies, the evidence level is II for percutaneous neurolysis in managing lumbar disc herniation.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.73.4-73.4
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• 2019

Most of the galaxy mass is known to be occupied by dark matter. However, it is difficult to directly measure the mass and distribution of dark matter in a galaxy. Recently, the velocity dispersion of the stellar population in a galaxy's center has been suggested as a possible probe of the mass of the dark matter halo. In this study, we test and verify this hypothesis using the kinematics of the satellite galaxies of isolated galaxies. We use the Friends-of-Friends (FoF)algorithm to build a catalog of primary galaxies and their satellite galaxies from the Sloan Digital Sky Survey (SDSS) DR 12. We calculate the dynamical mass of the primary galaxies from the velocity dispersion of their satellite galaxies. We then investigate the correlation between the dynamical mass and the central velocity dispersion of the primary galaxies. The stellar velocity dispersion of the central host galaxies has a strong linear correlation with the velocity dispersion of their satellite galaxies. Also, the stellar velocity dispersion of the central galaxy is strongly correlated with the dynamical mass of the galaxy, which can be described as a power law. The results of this study show that the central velocity dispersion of the primary galaxies is a good proxy for tracing the mass of dark matter halo.

• Journal of Daesoon Thought and the Religions of East Asia
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• v.3 no.1
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• pp.57-85
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• 2023

The politico-economic waives of Western imperialism and colonialism, along with Christianity, affected East Asia's geopolitical landscape in the nineteenth and twentieth centuries. While the Korean people (of the Joseon Dynasty) witnessed the incompetence of Buddhism, Confucianism, and folk religions in maintaining social cohesion with a sense of frustration, the new religious movements (NRMs) emerged to provide altrnative teachings of hope through historical figures like Choe Je-u, Kang Il-sun (or Kang Jeungsan), Na Cheol, and Pak Chungbin. In terms of popularity, colonial Korea (1910-1940) was impressed by the native groups of Cheondogyo (=Donghak), Bocheongyo, and Mugeukdo. Son Byong-hee (1861-1922) was the third leader of the first Korean NRM, but both Cha Gyeong-seok (1880-1936) and Jo Cheol-Je (= Jo Jeongsan) (1895-1958) participated in the post-Jeungsan grassroots movements. How, then, did both of these new religions originate? How did they conceptualise their deities and interpret their teachings differently? What was their policy for national independence? The article explores the socio-religious leaders, historical origin, organizational structure, deities, teaching and doctrines, patriotism, and conflicts of both NRMs in a comparative context. As such, this article argues that they both maintained patriotic characteristics, but that Cha's Bocheongyo community with its ' 60-executives' system (60 bang) failed to manage their internal conflicts effectively. Meanwhile, Jo Cheol-Je of Mugeukdo had the charismatic leadership needed to maintain Mugeukdo, despite being seen as a pseudoreligion under the colonial pressure of Shintoism.

• Clinics in Shoulder and Elbow
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• v.18 no.4
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• pp.229-236
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• 2015

Background: Twenty-six patients (12 male and 14 female) with symptomatic scapular winging caused by serratus anterior dysfunction were managed by split pectoralis major tendon transfer (sternal head) with autogenous hamstring tendon augmentation from 1998 to 2006. Methods: Twenty-five patients showed positive results upon long thoracic nerve palsy on electromyography. The mean duration of symptoms until surgery was 48 months (range, 12-120 months). Four patients had non-traumatic etiologies and 22 patients had traumatic etiologies. On follow-up assessment for functional improvement, a Constant-Murley score was used. Twenty-one patients were completely evaluated, while five patients who had less than 12 months of follow-up were excluded. Results: Pain relief was achieved in 19 of the 21 patients, with 20 patients showing functional improvement. The pain scores improved from 6.0 preoperatively to 1.8 postoperatively. The mean active forward elevation improved from $108^{\circ}$ (range, $20^{\circ}-165^{\circ}$) preoperatively to $151^{\circ}$ (range, $125^{\circ}-170^{\circ}$) postoperatively. The mean Constant-Murley score improved from 57.7 (range, 21-86) preoperatively to 86.9 (range, 42-98) postoperatively. A recurrence developed in one patient. Of the 21 patients, ten had excellent results, six had good results, four had fair results, and one had poor results. Conclusions: Most patients with severe symptomatic scapular winging showed functional improvement and pain relief with resolution of scapular winging.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.579-581
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• 2004

Recently, claims have been made of the detection of 'warm-hot' gas in the intergalactic medium. Kaastra et al. (2003) claimed detection of ${\~} 10^6$ K material in the Coma Cluster but studies by Arnaud et al. (2001), and our analysis of the Chandra observations of Coma (Vikhlinin et al. 2001), find no evidence for a $10^6$ K gas in the cluster. Finoguenov et al. (2003) claimed the detection of $3 {\times} 10^6$ gas slightly off-center from the Coma Cluster. However, our analysis of ROSAT data from this region shows no excess in this region. We propose an alternative explanation which resolves all these conflicting reports. A number of studies (e.g. Robertson et al., 2001) have shown that the local interstellar medium undergoes charge exchange with the solar wind. The resulting recombination spectrum shows lines of O VII and O VIII (Wargelin et al. 2004). Robertson & Cravens (2003) have .shown that as much as $25\%$ of the Galactic polar flux is heliospheric recombination radiation and that this component is highly variable. Sporadic heliospheric emission could account for all the claims of detections of 'warm-hot' gas and explain the conflicts cited above.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1622-1628
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• 2007

We characterized the efficacy of an electrostatic precipitator (ESP) air-cleaner in reducing the concentration of Serratia marcescens in an enclosed space. We used an experimental room ($4.5{\times}3{\times}2.9\;m$) in which electrostatic air-cleaners were located. Two air-cleaners enhanced the equivalent ventilation rates in the chamber by about 3.3 air changes per hour (ACH) over the 2 ACH provided by the mechanical ventilation system. Natural die-off of the organisms provided an additional equivalent of 3 ACH, so that the total ventilation rate with the ESP air-ccleaners was 8.3 ACH. We also examined whether the ESP air-cleaners altered the deposition of Serratia marcescens aerosols on the experimental room surfaces. We did not find any significant differences in the number of colony forming units recovered from surfaces with and without the air-cleaners. We installed UV lights inside the ESPs and determined if UV light, in addition to electrical fields, increased the efficacy of the ESPs. The presence of UV light inside the ESP reduced S. marcescens aerosols by approximately 2 ACH. Finally, a box model indicates that the efficiency of the air-cleaner increases for both biological and nonbiological particles at ventilation rates of 0.2-1, which are typical for residential settings.