• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.51.1-51.1
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• 2016

We revisited a recent dust emission observed at a main-belt asteroid P/2010 A2 in terms of dynamical properties of dust particles and large fragments. This is a continued research that we made a presentation at the Korean Astronomical Society 2016 Spring Meeting, but we have strengthened the dynamical analysis of the ejecta to afford the conclusive evidence for the enigmatic phenomenon. We thus constructed a model to reproduce the morphology of the dust cloud based on the dust dynamics, and succeeded in reproducing the observed morphologies in different epochs over several years. For further analysis, we reconstructed the proper motion of large fragments with respect to the dust emission source estimated from our dust model. We found that (i) the dust cloud morphologies and (ii) observed trajectories of fragments are reasonably explained only when we assumed that both were ejected from a position where no object was detected from any observations. This result suggests that the original body was shattered by an impact, leaving only debris into space. In this presentation, we will compare our results with impact laboratory studies and provide an impact interpretation of the P/2010 A2 activity.

• Journal of Radiation Protection and Research
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• v.20 no.3
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• pp.187-200
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• 1995

This paper reviews studies on potential health effects of electric and magnetic fields at extremely low frequencies(ELF). Recent studies focus on the epidemiological investigation of cancer, reproductive outcome and neurobehavioral effects due to residential and occupational exposure to ELF. Laboratory experiments are also carried out to find the possible mechanism of biological effects of ELF. Firm conclusion regarding whether ELF cause cancer are not yet conclusive but suggestive and other health effects of exposure to ELF have also been suggested but the evidence is even weaker than that related to cancer.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.655-658
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• 2002

The present paper investigated the effect of ultrasonic vibrations on the melting process of a phase-change material (PCM). Furthermore, the present study considered constant heat-flux boundary conditions unlike many of the previous researches, which had adopted constant wall-temperature conditions. Therefore in the study, modified dimensionless numbers such as Stefan and Rayleigh were adopted to represent heat transfer results. The experimental results revealed that ultrasonic vibrations accompanied the effects like agitation, acoustic streaming, cavitation, and oscillating fluid motion, accelerating the melting process as much as 2.5 times, compared with the result of natural melting (i. e., the case without ultrasonic vibration). Such effects are believed to be a prime mechanism in the overall melting process when ultrasonic vibrations were applied. Subsequently, energy could be saved by applying the ultrasonic vibrations to the natural melting In addition, various time-wise dimensionless numbers provided a conclusive evidence of the important role of the ultrasonic vibrations on the melting phenomena of the PCM.

• Journal of Information Technology Applications and Management
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• v.11 no.3
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• pp.147-159
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• 2004

Empirical evidence on the maintainability of object-oriented systems is far from conclusive, partly due to lack of representativeness of the subjects and systems used in the study. The present research empirically examined this issue with the systems that are mission-critical. currently operational and maintained by professionals. It was found that the 00 group appeared to consume less time while maintaining more amount of software artifacts than the NOO counterpart. This economical utilization of time appeared evident regardless of software development life cycle. This was due to the usefulness of UML for impact analysis which contributed to effective comprehension and communication. Insufficient design specifications led to ambiguity and costly defects in transferring design solutions to development. Also. the encapsulation of 00 seemed to reduce mental loads at maintenance tasks and improved code reuse. However, the number of files to manage increased and thus. dependency management is required for the 00 systems.

• Journal of Wellbeing Management and Applied Psychology
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• v.3 no.1
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• pp.11-20
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• 2020

Anecdotal reports indicate that maladaptive patterns of Internet use constitute behavioral addiction. Internet addiction is characterized by unrestrained and awfully controlled engrossment or behaviors regarding internet access that lead to impairment, stress, dimensionally measured depression, indicators of social separation and anguish. By reviewing and analyzing approximately 100 articles we present evidence that are able to provide an overview of the main themes and proclivity covered by existing and relevant studies. The vital detection of this research unveils that many factors related to social, demographic, lifestyle changes related constructs have a bearing on the phenomenon of internet addiction strongly. This study not only reached certain conclusions for both theory and practice, but also defined future lines of research according to the gaps detected by the study's results. The main findings from this literature, though not conclusive, but will help the researcher and policymakers to obtain a better understanding and description of the problem faced by the youth and necessary to develop some remedies to lessen the addiction phenomenon.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.3
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• pp.319-326
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• 2022

This study investigates the specific and conclusive reasons why a company issues bonus shares, as well as the rationale and the best timing for bonus share issuance. The study examines Carlsberg's annual reports from 1988 to 2004 to evaluate the factors that influence bonus share payments and timing. Examine supporting evidence from other businesses as well. An analysis of Carlsberg Brewery Malaysia Berhad's bonus shares granted from its inception to 2004 found that the announcement of bonus shares would increase the company's share price. As a result, the findings suggest that bonus shares are issued to correct market asymmetry. This research supports the idea that issuing bonus shares would increase the stock price, resulting in increased liquidity. Hence, companies issue bonus shares to boost their liquidity and to convey private positive information to their shareholders. This research adds to the literature by focusing on the timing and key features of bonus share issuing. It implies that dividend policy should be customized to market imperfections. As a result, dividend policies would differ significantly between organizations based on the weights each of the imperfections has on the firm and shareholders.

• East Asian Economic Review
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• v.27 no.2
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• pp.145-176
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• 2023

This paper investigates short selling behavior, particularly by foreign investors, during event days of non-normal times on an intraday basis in the Korean stock market around the global financial crisis. Although, in the several subsamples, we cannot exclude the predatory short-selling possibility, we did not find any conclusive evidence of abusive short selling behaviors in the overall intraday trading activities. While foreign investors demonstrate higher levels of participation in short-sale trading, their impact on price declines is not as pronounced compared to the effects of pure selling. Following the lift of the short-sale ban, foreign investors appear to engage in long selling trading more frequently, and their influence on price changes primarily stems from long selling rather than short selling compared to the past.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.383-392
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• 2000

Objective : We have reviewed the potential cancer preventive and other relevant properties of Panax ginseng C. A. Meyer, which has been traditionally used as a natural tonic in oriental countries. Data identification and study selection: Publications on Panax ginseng and its relation to cancer were obtained from the Medline database (1983-2000) and by checking reference lists to find earlier reports. The reports cover experimental models and human studies on cancer-preventive activity, carcinogenicity and other beneficial or adverse effects. In addition, possible mechanisms of chemoprevention by ginseng were also considered. Results : Published results from a cohort and two case-control studies in Korea suggest that the intake of ginseng may reduce the risk of several types of cancer. When ginseng was tested in animal models, a reduction in cancer incidence and multiplicity at various sites was noted. Panax ginseng and its chemical constituents have been tested for their inhibiting effect on putative carcinogenesis mechanisms (e.g., cell proliferation and apoptosis, immunosurveillance, angiogenesis); in most experiments inhibitory effects were found. Conclusion : While Panax ginseng C. A. Meyer has shown cancer preventive effects both in experimental models and in epidemiological studies, the evidence is currently not conclusive as to its cancer-preventive activity in humans. The available evidence warrants further research into the possible role of ginseng in the prevention of human cancer and carcinogenesis.

• Physical Therapy Korea
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• v.26 no.4
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• pp.70-76
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• 2019

Background: An excessive pronated foot is defined as a flattening or complete loss of the medial longitudinal arch. Excessive foot pronation is considered to have high risk factors of overuse injuries in the lower limb. Various treatments have been investigated in attempts to control excessive pronation. Objects: This meta-analysis identifies the effects of an anti-pronation taping technique using different materials. Methods: The electronic databases used include MEDLINE, the Physiotherapy Evidence Database (PEDro), Science Direct, the Korean Studies Information Service System (KISS), the Research Information Sharing Service (RISS), the Korea National Library, and the Korean Medical Database (studies published up to July 31, 2019). The database search used the following keywords: "foot drop" OR "foot arch" OR "foot pronation" OR "flat foot (pes planus)" AND "taping" OR "support." Eight eligible studies were analyzed to determine the effectiveness of anti-pronation taping in study and control groups. Results: The overall random effect size (Hedges'g) of the anti-pronation taping technique was 0.147 (95% confidence interval [CI]: -.214 to .509). When the effect (Hedges' g) was compared by the type of tape material, rigid tape (RT; Lowdye taping) was .213 (95% CI: -.278 to .704) and kinesiotape (KT; arch support taping) was -.014 (95% CI: -.270 to .242). Based on this meta-analysis, it was not possible to identify the extent to which anti-pronation taping was effective in preventing navicular drop, improving balance, or changing foot pressure. Only three of the eight eligible studies applied KT on excessive pronated feet, and the outcome measure areas were different to those of the RT studies. The KT studies used EMG data, overall foot posture index (FPI) scores, and rear foot FPI scores. In contrast, the RT studies measured navicular heights, various foot angles, and foot pressure. Conclusion: This review could not find any conclusive evidence about the effectiveness of any taping method for patients with pronated feet. Future studies are needed to develop the anti-pronation taping technique based on the clinical scientific evidence.

• Nutrition Research and Practice
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• v.15 no.2
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• pp.137-159
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• 2021

Long-chain (LC) n-3 polyunsaturated fatty acids (n-3 PUFAs), in particular docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are nutrients involved in many metabolic and physiological processes, and are referred to as n-3 LCPUFA. They have been extensively studied for their effects in human nutrition and health. This paper provides an overview on metabolism, sources, dietary intake, and status of n-3 LCPUFA. A summary of the dietary recommendations for n-3 LCPUFAs for different age groups as well as specific physiological conditions is provided. Evidence for n-3 LCPUFA in cardiovascular diseases, including new studies, is reviewed. Expert recommendations generally support a beneficial effect of n-3 LCPUFA on cardiovascular health and recommend a daily intake of 500 mg as DHA and EPA, or 1-2 servings of fish per week. The role of n-3 LCPUFA on brain health, in particular neurodegenerative disorders and depression, is reviewed. The evidence for beneficial effects of n-3 LCPUFA on neurodegenerative disorders is non-conclusive despite mechanistic support and observational data. Hence, no definite n-3 LCPUFA expert recommendations are made. Data for the beneficial effect of n-3 LCPUFA on depression are generally compelling. Expert recommendations have been established: 200-300 mg/day for depression; up to 1-2 g/day for major depressive disorder. Recent studies support a beneficial role of n-3 LCPUFAs in reducing the risk for premature birth, with a daily intake of 600-800 mg of DHA during pregnancy. Finally, international experts recently reviewed the scientific evidence on DHA and arachidonic acid (ARA) in infant nutrition and concluded that the totality of data support that infant and follow-on formulas should provide both DHA and ARA at levels similar to those in breast milk. In conclusion, the available scientific data support that dietary recommendations for n-3 LCPUFA should be established for the general population and for subjects with specific physiological conditions.