• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.407-411
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• 2002

Ternary sequences are digital codes consisting of discrete values -1, 0, and 1 only. They are advantageous in that the correlation can be carried out using additions only Also, they feature an ideal circular autocorrelation function, but in channel characterization tasks, the usual requirement is that the linear autocorrelation function be ideal, i.e., a Kronecker delta function. In this article, we consider two approaches to improving their linear autocorrelation or crosscorrelation properties: one is an inverse filtering method with theresholding and the other is a singular value decomposition (SVD) method. Both methods are simulated under noisy circumstances. The inverse filtering method resulted in an improvement in peak sidelobe level of about 1㏈ at an SNR of 30㏈, and the SVD method showed similar performances, albeit more sensitive to noise depending on the singular value selection strategy.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.1
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• pp.53-63
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• 2014

Growing of number of elderly populations, which may be caused by improved quality of life and decreased the percentage of mortality. Although there is a declining rate of the edentulous patients, more patients are advancing into older age groups, and the substantial number of edentulous patients are increasing. For these edentulous patients, complete denture cannot substitute natural teeth, but it is a staple prosthetic treatment. Generally, the success of dentures has been evaluated on the basis of whether or not patients comfortable and were able to masticate with their dentures. Acceptance of complete denture is complex for patients and related to psychological factors of patients, physical state, and the technical quality of dentures. In addition to that, many factors influence to satisfaction of patients to the complete dentures. In this review article, evaluate various factors related on satisfaction of denture wearers and methods of evaluate satisfaction.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.30 no.3
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• pp.88-102
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• 2017

Objectives : The aim of this study is to review domestic clinical studies about dizziness in Korean medicine. Methods : Population key words "현훈(Hyeonhoon), 현기증(Hyeongijeung), 어지럼(Eojireom), 어지러움(Eojireoum), 실신(Silsin), 眩暈(Hyeonhoon), 眩氣症(Hyeongijeung), 失神(Silsin)" were searched on five database systems(DBpia, KISS, KMbase, NDSL, RISS) from September, 13th to September, 15th, 2016. 60 clinical studies were collected and classified by published journal, year, etiologic disease, study design, dizziness assessment tools of studies, study results, evaluation of disease pattern and process, interventions(herbal medicine and acupuncture treatment points), and number of studies which chose that prescription. Results & Conclusions : Dizziness was researched constantly since 1998 and 7 clinical stuides were issued 2007, the most. The journal which the most studies were presented was Journal of korean oriental internal medicine(12 studies over 60, 20%). Original article were 12(20.0%) and case reports were 48(80.0%) among 60 studies. BPPV was reported as a etiologic disease on 9 studies(20.45%) among 44 studies. VAS was used mainly as dizziness assessment tools of studies(26 studies over 38, 68.42%). 9 studies(15.0%) got evaluation of disease pattern and process among 60. Banhabaekchulcheonma-tang was reported as a herbal medicine prescription on 9 over 44 studies(20.45%) and ST36 was chosen acupuncture point most(24 over 45 studies, 53.33%). It doesn't have enough representativenes but has meaning to apprehend present tendency to treat dizziness in Korean medicine clinical studies.

• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.215-220
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• 2005

It is common for clinicians to encounter endodontically tl·treated teeth that contain posts within their roots. If endodontic treatment is failed, these posts must be removed to facilitate successful nonsurgical retreatment. There have been many techniques such as ultrasonic instrument, Ruddle post removal system, Eggler post remover and Masserann kit developed to facilitate removal of posts from the root canal space. But these methods may be disadvantageous because long length of time required for post removal and fracture of post or teeth. In now days new post removal technique using ATD automatic bridge remover was introduced. Advantages of this method are simple and short time consuming compare to others. This article served as a successful case report of post removal using ATD automatic bridge remover.

• The Korean Journal of Financial Management
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• v.26 no.3
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• pp.31-64
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• 2009

This article investigates the short-term cash flow exposures to Korea's major trading partners' currencies based on the kospi and kosdaq firm data from 2000 to 2008. The cash flow approach allows us to analyze the influence on operational performances of individual firm's hedging strategies. Taken all three foreign exchange rates together, more than 30% of the sample firms exhibit significant exposure. Given that the short-term cash flow is rather easy to hedge, the result proves a poor exchange rate risk management practices of Korean firms. Kosdaq firms are more exposed than Kospi firms. On the contrary to the previous researches using stock prices, the operational cash flows show a positive relationship with the value of foreign currencies. The exchange rate-firm sample further shows that the size and leverage affect the level of exposure.

• Spatial Information Research
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• v.17 no.3
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• pp.389-395
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• 2009

In spite of many numerical analysis of debris flow, a little information has been found out. In this paper the watershed is divided to apply rainfall runoff and to estimate debris flow integrating flow and soil article. We use the contour data to extract spatially distributed topographical information like stream channels and networks of sub-basins. A Quasi Digital Elevation Model (Q-DEM) is developed, integrated, and adopted to estimate runoff based on marked one. As a results, it has been found out that the debris flow was close to observed flow hydrograph. Because debris flow is finished in 30 second, it is important that we have to prepare its prior countermeasure to minimize the damage of debris flow. The GIS-linked model will provide effective information to plan river works for debris flow.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.17.1-17.7
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• 2018

Background: Bisphosphonate (BP) has the ability to thicken the cortical bone. In addition, it has been reported that the cortical bone thickened by BP has relation to the medication-related osteonecrosis of the jaw (MRONJ). Therefore, the objective of this article is to analyze the ratio as well as thickness of cortical bone in the mandible using computed tomography (CT) and to evaluate it as the predictive factor of MRONJ. Methods: The thickness of the cortical bone was measured on a paraxial view of the CT showing the mental foramen in 95 patients: 33 patients with MRONJ (3 males, 30 females), 30 patients taking BP without MRONJ (2 males, 28 females), and 32 controls (9 males, 28 females). Also, the ratios of the cortical bone to the total bone were obtained using the measured values. Based on these results, we compared the difference of mandibular cortical bone ratio between the three groups. Results: The average cortical bone thickness was measured as 3.81 mm in patients with MRONJ, 3.39 mm in patients taking BP without MRONJ, and 3.23 mm in controls. There was only a significant difference between patients with MRONJ and controls (P < 0.05). On the other hand, the average mandibular cortical bone ratio was measured as 37.9% in patients with MRONJ, 27.9% in patients taking BP without MRONJ, and 23.3% in controls. There was a significant difference between all groups (P < 0.05). Conclusion: The mandibular cortical bone ratio is large in order of patients with MRONJ, patients taking BP without MRONJ, and controls. This result suggests that the mandibular cortical bone ratio would be very useful to predict the development of MRONJ.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.1-12
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• 2017

Many stochastic processes satisfy the Markov property exactly or at least approximately. An interested property in the Markov process is the first passage time. Since the sequential analysis by Wald, the approximation of the first passage time has been studied extensively. The Statistical computing technique due to the development of high-speed computers made it possible to calculate the values of the properties close to the true ones. This article introduces an exponentially weighted moving average (EWMA) control chart as an example of the Markov process, and studied how to calculate the average run length with problematic issues that should be cautioned for correct calculation. The results derived for approximation of the first passage time in this research can be applied to any of the Markov processes. Especially the approximation of the continuous time Markov process to the discrete time Markov chain is useful for the studies of the properties of the stochastic process and makes computational approaches easy.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.205-209
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• 2016

The influence of titania nanorods with an average diameter of 10 nm and an average length of 30 nm on the electrohydrodynamic instability of block copolymer (polystyrene-b-poly(2-vinylpyridine)) thin film was investigated in this article. The presence of titania nanorods increased the dielectric constant of the film, which resulted in a systematic reduction in the wavelength of the surface instability. Cross-sectional transmission electron microscopy analysis indicated that the migration/aggregation of titania nanorods did not occur as a result of the applied electric field. This work can provide a simple route to the pattern formation using electrohydrodynamic instability with an aid of nanoparticles.

• Journal of Convergence for Information Technology
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• v.11 no.12
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• pp.80-89
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• 2021

In order to combat the spread of COVID-19, on January 30, 2020, the World Health Organization declared that the spread of COVID-19 has met the criteria of a "Public Health Emergency of International Concern" under Article 1 of the International Health Regulations(2005) and proposed a variety of preliminary recommendations to fight against the pandemic accordingly. All of a sudden, people are ordered to wear face-masks in public-which is forbidden for different reasons in many jurisdictions. Of course, the legal world was hit by the virus as well. Needless to mention that where economic and social life will change so drastically, the legal world will change(ex. virtual hearing) as well. Most probably, it will not ever be the same after COVID-19. And where the whole legal world will change, it is easy to state the obvious, namely that COVID-19 has and will have an impact on international arbitration as well. This paper will describe how international arbitration is dealing with this new challenge.