• ETRI Journal
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• v.27 no.4
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• pp.377-384
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• 2005

We investigate near-infrared light (NIR) propagation in a model of an adult head using an extensive Monte Carlo (MC) simulation. The adult head model is a four-layered slab which consists of a surface layer, a cerebrospinal fluid layer, a gray-matter layer, and a white-matter layer. We study the effects of a refractive index mismatch on the model, calculating the intensity of detected light, mean flight time, and partial mean flight time of each layer for various refractive indices of the cerebrospinal fluid layer as functions of source-detector spacing. The Monte Carlo simulation shows that the refractive index mismatch presents very rich results including rapidly decaying intensity of detected light and a peak and cross-over in the partial mean flight time with source-detector spacing. We also investigate spatial sensitivity profiles at various source-detector spacings, discussing the index mismatch effect on the model.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.20 no.6
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• pp.33-40
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• 2018

The coastal village in Woljeong-ri, Jeju is highly preferred by tourists because of its unique natural landscape different from inland areas. Especially, the number of buildings in the coastal area of the village is increasing due to escalating commercial value. Buildings are densely developed, along the seaside, resulting in privatization of coastal landscape. This results in blocking of landscape and psychological exchanges between the coastal village and coast. This study analyzed the actual conditions of coastal landscape before and after 2010, when the number of tourists and demand for development were increased in the coastal area of the coastal village in Woljeong-ri, Jeju. In this study, open index, visible horizontal index, elevation angle, elevation blockage and visible facade index were used to compute objective indicators of coastal landscape status. The analysis reveals visible facade index, a complex landscape assessment indicator, was increased by 7 times after 2010 as compared with before 2010. As such, there are many coastal villages in Jeju similar to Woljeong-ri that have a high landscape value and are in need of management. A comprehensive measure including a system for management of coastal landscape is urgently required to create narrative landscape in Jeju.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.1113-1119
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• 2021

This study aims to determine the impact of the news coverage of the COVID-19 pandemic on the composite stocks' movement (IHSG) in Indonesia. This study used secondary data of daily time series with an observation range of March 2020-June 2020. This study used three main variables, namely, COVID-19 news, the daily price of a composite stock market index (IHSG), and interest rate. This study clarifies pandemic news into two forms to facilitate quantitative analysis, namely, good news and bad news. Both pandemic news conditions, which have been clarified, are then processed into the index and reprocessed along with two other variables using vector autoregressive (VAR). The results showed that the good news have a dominant effect on developing the composite stock price index (IHSG) in Indonesia during the COVID-19 pandemic. Although the good news dominates the composite stock price index (IHSG) movement in Indonesia, the bad news must also be anticipated. By implementing a series of macroeconomic policies that follow the conditions of the composite stock price index (IHSG) movements on the stock exchange floor, the bad news response can decrease the potential for a decline in investor confidence, so that the financial system's macroeconomic stability is maintained.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.246-259
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• 2021

IMO stability regulations include various stability parameters such as GM values. To assess the stability of the ships, we should check all stability parameters of the IMO requirements. However, since this process is complex, a more convenient way to evaluate stability performance is required. In this research, the index for marine ship intact stability assessment (IMSISA) model was developed to solve these problems. The IMSISA model consists of a stability index calculation module and a stability assessment module. In the stability index calculation module, ten stability parameters, including GM, were used to develop the stability index, which has the advantage of being able to quantify the ship stability. The stability assessment module uses the stability index value to determine the stability status of the ship and provides the captain with stability management guidelines. To verify the proposed model, the basic stability calculations were performed for two model ships in 32 loading situations. The proposed model was found to provide better performance in the stability assessment than the previous study. By applying the IMSISA model to the ships, the captain can assess the ship stability more quantitatively and efficiently.

• Journal of The Korean Astronomical Society
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• v.36 no.spc1
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• pp.93-99
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• 2003

Various attempts have been made to explain the: pronounced seasonal and universal time (UT) variations of geomagnetic indices. As one of such attempts, we analyze the hourly-averaged auroral electroject indices obtained during the past 20 years. The AU and AL indices maximize during summer and equinoctial months, respectively. By normalizing the contribution of the solar conductivity enhancement to the AU index, or to the eastward electrojet, it is found that the AU also follows the same semiannual variation pattern of the AL index, suggesting that the electric field is the main modulator of the semiannual magnetic variation. The fact that the variation pattern of the yearly-mean AU index follows the mirror image of the AL index provides another indication that the electric field is the main modulator of magnetic disturbance. The pronounced UT variations of the auroral electrojet indices are also noted. To determine the magnetic activity dependence, the probability of recording a given activity level of AU and AL during each UT is examined. The UT variation of the AL index, thus obtained, shows a maximum at around 1200-1800 UT and a minimum around 0000-0800 UT particularly during winter. It is closely associated with the rotation of the geomagnetic pole around the rotational axis, which results in the change of the solar-originated ionospheric conductivity distribution over the polar region. On the other hand the UT variation is prominent during disturbed periods, indicating that the latitudinal mismatch between the AE stations and the auroral electrojet belt is responsible for it. Although not as prominent as the AL index, the probability distribution of the AU also shows two UT peaks. We confirm that the Dst index shows more prominent seasonal variation than the AE indices. However, the UT variation of the Dst index is only noticeable during the main phase of a magnetic storm. It is a combined result of the uneven distribution of the Dst stations and frequent developments of the partial ring current and substorm wedge current preferentially during the main phase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.565-570
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• 2017

The various techniques proposed previously to obtain a good antireflection(AR) coating induce a scattering of incident light by nanoparticles or control the refractive index by using different materials. This paper compares a suggested graded index profile with the quintic index profile previously suggested for producing an index profile that gives good performance from an AR coating. We assume the structure of the AR coating has three, six, and nine layers with 180 nm total thickness. The wavelength of incident light ranges from 300 nm to 1100 nm. We use the transfer matrix theory for a single layer to obtain the reflectivity of three, six, and nine layers. The reflectivity of two different index profiles with three, six, and nine layers is compared. As a result, the suggested graded index profile shows lower reflectivity than the quintic index profile with three layers, especially in the wavelength range from about 600 nm to 1100 nm. Therefore, we expect that these results can be applied to optical devices and filters in the range from visible(red) to near infrared.

• Tuberculosis and Respiratory Diseases
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• v.70 no.3
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• pp.235-241
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• 2011

Background: The rising prevalence of asthma may be associated with the rising prevalence of obesity in developed nations. There are several studies showing that obesity increases the risk of asthma in adults. We investigated the association of each body composition scale and bronchial hyper-responsiveness. Methods: This study involved a retrospective review of the existing records for 279 subjects with respiratory symptoms, who underwent a pulmonary function test, a methacholine challenge test and a body composition test between May 2007 and June 2009. Results: Of the 279 subjects, 179 (64%) were female. There was a statistically significant difference in fat free mass and in fat free mass index between the normal bronchial responsiveness group and bronchial hyper-responsiveness group (p=0.036; p=0.000). There was no significant differences in body mass index, in fat mass and fat free mass index in the normal bronchial responsiveness group and bronchial hyper-responsiveness group in males. However in females, body mass index and fat free mass index were increased in the bronchial hyper-responsiveness group (p=0.044; p=0.000). Total body water (kg), fat free mass (kg) and soft lean mass (kg) were significantly different between the normal bronchial responsiveness group and bronchial hyper-responsiveness group (p=0.002; p=0.000; p=0.000). Conclusion: This study showed significant differences in fat free mass and in fat free mass index between the normal bronchial responsiveness group and the bronchial hyper-responsiveness group. In females, BMI, soft lean mass, and total body water showed significant differences between the normal bronchial responsiveness group and the bronchial hyper-responsiveness group. We concluded that bronchial hyper-responsiveness was associated with not only body mass index but also fat free mass index in female bronchial asthma.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.201-204
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• 2016

This study aimed to quantify associations of the human development inequality (HDI) index with incidence, mortality, and mortality to incidence ratios for eight common cancers among different countries. In this ecological study, data about incidence and mortality rates of cancers was obtained from the Global Cancer Project for 169 countries. HDI indices for the same countries was obtained from the United Nations Development Program (UNDP) database. The concentration index was defined as the covariance between cumulative percentage of cancer indicators (incidence, mortality and mortality to incidence ratio) and the cumulative percentage of economic indicators (country economic rank). Results indicated that incidences of cancers of liver, cervix and esophagus were mainly concentrated in countries with a low HDI index while cancers of lung, breast, colorectum, prostate and stomach were concentrated mainly in countries with a high HDI index. The same pattern was observed for mortality from cancer except for prostate cancer that was more concentrated in countries with a low HDI index. Higher MIRs for all cancers were more concentrated in countries with a low HDI index. It was concluded that patterns of cancer occurrence correlate with care disparities at the country level.

• Journal of Digital Convergence
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• v.18 no.4
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• pp.113-119
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• 2020

This study analyzed the relationship between consumers' awareness of marine products and the food index level, which is a sub-domain of the Pukyong Maritime Index. Specifically, the evaluation of marine products by Korean consumers verified the relationship between taste, nutrition, diversity, price, and safety-related systems and the food index. The analysis results were as follows. First, it was found that consumers' awareness of marine products had a significant positive correlation with the food index. Second, as a result of the regression analysis, the food index had an effect on the order of nutrition, taste, and price. These findings are required to understand consumers' awareness of aquatic products, and the food index can be used as the center of northeast asia sea region to provide a framework for improving consumer's satisfaction.

• Journal of Industrial Convergence
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• v.21 no.1
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• pp.87-93
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• 2023

Determining the timing of buying and selling in stock investment is one of the most important factors to increase the return on stock investment. Buying low and selling high makes a profit, but buying high and selling low makes a loss. The price is determined by the quantity of buying and selling, which determines the price of a stock, and buying and selling is also related to corporate performance and economic indicators. The fear and greed index provided by CNN uses seven factors, and by assigning weights to each element, the weighted average defined as greed and fear is calculated on a scale between 0 and 100 and published every day. When the index is close to 0, the stock market sentiment is fearful, and when the index is close to 100, it is greedy. Therefore, we analyze the trading criteria that generate the maximum return when buying and selling the US S&P 500 index according to CNN fear and greed index, suggesting the optimal buying and selling timing to suggest a way to increase the return on stock investment.