• Polymer(Korea)
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• v.29 no.4
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• pp.344-349
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• 2005

Polyurethanes(PUs) were synthesized by reaction of isophorone diisocyanate, acetylbutyl citrate, and 3 types of polycaprolactone diol. Their structures were confirmed by FT-IR and NMR spectrometer. And, their thermal and mechanical properties were measured by TGA ud UTM. The effective network chain lengths ($\bar{M}_c$), measured by compressive modulus apparatus, were about $8000\~24000$ g/mol. As crosslinking density and amount of hard segment increased, tensile strength increased and elongation decreased. As the crosslinking density of PUs increased, thermal property inproved. When the ratio of NCO/OH is 1.1, maximum crosslinking density was achieved.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.27-34
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• 2020

The study investigates herding behavior in cryptocurrencies in different situations. This study employs daily returns of major cryptocurrencies listed in CCI30 index and sub-major cryptocurrencies and major stock returns listed in Dow-Jones Industrial Average Index, from 2015 to 2018. Quantile regression method is employed to test the herding effect in market asymmetries, inter-dependency and intra-dependency cases. Findings confirm the presence of herding in cryptocurrency in upper quantiles in bullish and high volatility periods because of overexcitement among investors, which lead to high volume trading. Major cryptocurrencies cause herding in sub-major cryptocurrencies, but it is a unidirectional relation. However, no intra-dependency effect among cryptocurrencies and equity market is observed. Results indicate that in the CKK model herding exists at upper quantile in market that may be due when the market is moving fast, continuously trading, and bullish trend are prevailing. Further analysis confirms this narrative as, at upper quantile, the beta of bullish regime is negative and significant, meaning the main source of market herding is a bullish trend in investment, which increases market turbulence and gives investors opportunity to herd. Also, we found that herding in cryptocurrencies exits in high volatility periods, but this herding mostly depends on market activity, not market movement.

• Korean Journal of Digital Imaging in Medicine
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• v.7 no.1
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• pp.7-13
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• 2005

Purpose : Image plate (IP) is substituted for film in computed radiography. This study is to investigate into a variation of contrast and detail by the number used of image plate in computed radiography. Materials and Methods : A Contrast-Detail(CD)-RAD 2.0 phantom(Nijmegen hospital, The Netherlands) was used for this study. The computed radiography(CR) CD-RAD phantom images were acquired at 40 kVp, 160 mA, 1.6 mAs, and small focus with the Shimadzu general radiography UD-150B-10 system and Fuji FCR 5000 image process system with speed of 200. The IP used including once, 5000 times, and 10000 times also was used. The numerical value of image quality figures (IQF) was produced by CD-RAD analyser(the program is installed in the directory), and then contrast-detail curve was drawn. Results : In this study, the value of IQF was 3.53 in IP used once, 3.40 in 5000 times, and 3.22 in 10000 times. Conclusions : There was a variation of contrast-detail curve by the number used of IP with contrast-detail phantom in computed radiography. Therefore, it is necessary that the IP with lower IQF and a shift of contrast-detail curve to the lower left part is used.

• Journal of Engineering Education Research
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• v.12 no.1
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• pp.42-56
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• 2009

This study derives the suggestions for promotion of internationalization of universities. The reasons for increase in number of international students were analyzed and present condition of international students has been investigated. Research and analysis of International students support program of government was performed. Moreover, the questionnaire was Prepared based on literature review of national and international policies for the support on international students and the survey was conducted on international students studying in engineering programs at graduate level. Finally, suggestions for government, university and education institutions have been made for the improvement of international student support programs to promote internationalization of universities.

• Journal of Magnetics
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• v.19 no.2
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• pp.140-145
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• 2014

The electrical transport properties of YBCO single layers thin film have been investigated using different physical techniques. For the purpose, the physical properties are probed numerically with help of simulation modelling. The physical transport properties were also estimated with temperature and magnetic fields limits using thermally-activated flux flow model with some modifications. The result of present simulation modelling indicated that the magnitude of activation energy depends on temperature and magnetic field. The simulations revealed thickness dependent physical transport properties including electrical and magnetic properties of deposited YBCO single layers thin films. Furthermore, it shows the temperature dependence of the pinning energy. In the nutshell, the result can be used to improve the Superconducting Properties ($T_c$) of the YBCO single layers thin films.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.205-212
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• 2020

This study seeks to examine the main factors, external and internal to the bank, that enhance bank lending. Bank lending is one of the connecting bridges in sustaining society. Internal factors consist of ROA, DPK, and CAR. External factors are economic growth and interest rate of Bank Indonesia. The population of this research consists of traditional commercial banks listed on the IDX over the 2014-2017 period. Samples were chosen by purposive sampling method. This study uses secondary data with 56 samples; data analysis uses multiple linear regression. The findings of the study show that internal factors have a greater impact on increasing bank lending than external factors. The main variable among internal factors that influences increase in bank lending is ROA. DPK is the internal factor with the smallest impact on increasing bank lending. The implication of the study is that determining the bank lending should take more account of CAR, DPK, ROA, BI interest rates, and economic growth in making decisions about the amount of lending. These variables can only have a slight effect on increasing lending, though. Besides, internal factors such as NPL, LDR or non-economic factors also need to be considered in channeling bank credit.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.241-250
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• 2020

This study examines the relationship between the attributes of board structure and the likelihood of financial distress for the non-financial sector of an emerging market characterized by concentrated ownership and family-controlled business. The present study utilized panel logistic regression to estimate the relationship between board structure attributes and the likelihood of financial distress. We used Altman Z-Score as a proxy for firm financial distress, as this tool measures the financial distress inversely. The study finds a significant relationship between board size and the likelihood of financial distress. The results show that a one-unit increase in board size would decrease the probability of financial distress by 3.4%. Further, we observe that a greater level of board independence is associated with a lower likelihood of financial distress. A one-unit increase in board independence would decrease the probability of financial distress by 20.4%. We also find a significant positive impact of leverage on the likelihood of financial distress. The present study contributes to the body of literature on board structure attributes and likelihood of financial distress in emerging markets, like Pakistan. Furthermore, the findings would be beneficial for corporate policymakers and investors in formulating corporate financial strategy and predicting business failure.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.1059-1068
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• 2020

This study aims to examine the influence of Islamic leadership and Islamic work culture on employee performance through work motivation and job satisfaction. This study was conducted at Universitas Islam Negeri (UIN) Walisongo Semarang, Indonesia, because so far, there is still very limited research on the relationships between Islamic leadership, work culture, and work motivation in educational personnel performance. The educational personnel performance is expected to increase at UIN Walisongo Semarang with continuous efforts to improve to survive and develop as much as possible. The population of this study was all educational personnel at UIN Walisongo Semarang, Indonesia. Of 186 people, only 127 people were involved in this study. The research method used was a survey method using primary data collected through questionnaires. This study's analysis technique employed multiple linear regression. The results uncovered that, out of the eight hypotheses proposed, six hypotheses were accepted. Islamic leadership and Islamic work culture were found to have no direct effect on employee performance. Besides, work motivation and job satisfaction became essential factors mediating Islamic leadership and Islamic work culture on employee performance. Spiritual values in leadership inspire employees to build the organization's vision and create job satisfaction, which in turn impacted employees' performance.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.251-257
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• 2020

The study investigates the role of commodity prices and tax purpose recognition on bitcoin prices. Since the introduction of bitcoin in 2008, emphasis has focused on economists, policy-makers and analysts drastically increasing bitcoin's accessibility and commodity values (Dumitrescu & Firică, 2014). This study employs GARCH and EGARCH from ARCH/GARCH family on daily nature data. We measure the volatile behavior of bitcoin by employing auto-regressive conditional heteroscedasticity model with the aim to explore the relationship between major commodities and bitcoin volatility. We focus on major commodities like gold, silver, platinum, and crude oil to be regressed with bitcoin. The daily prices of commodities were retrieved from www.investing.com and bitcoin prices from www.coindesk.com for the period from 29April 2013 to 16 October 2018. Results confirmed the currency's long-term volatile behavior, which is due to its composition and market dynamics, whereas the existence of asymmetric information effect is not confirmed. Tax recognition by other countries may in future help in controlling the volatility as bitcoin is not a country-specific security. But, only silver impacts on volatility in comparison to oil prices and platinum, which is due to its similar features with gold. Eventually, bitcoin can be used for risk diversification and money making.

• Acta Via Serica
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• v.2 no.1
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• pp.85-108
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• 2017

This paper details the advance of the "Hui" (回) people to Korea and their socioeconomic activities in forming their own community during the late Goryeo and early Joseon period. Hui (回) or Hui Hui (回回) is generally recognized as representative of Muslim culture in Chinese and Korean sources. From the $8^{th}$ century, Korean-Muslim cultural relations accelerated as an outcome of ancient Chinese-West Asian commercial transactions along the Silk Road. These contacts between Muslims and Koreans on the Korean peninsula are borne out by references to Korea found in 23 Islamic sources written between the $9^{th}$ and $16^{th}$ centuries by 18 Muslim scholars, including Ibn Khurdadbih, Sulaiman al-Tajir, and Mas'ud1 i. Ibn Khurdadbih was the first Arab who wrote of Muslims' residence in the Unified Silla Kingdom (661-935CE). However, in the period of Silla, we could not find any reliable written documents in Korea to show encounters between Korea and the Muslim world. In the Goryeosa (GS) chronicle, Muslim merchants who came to Korea were described as "Daesik" (大食: Tashi). Daesik (Tashi) is most probably derived from "Tajir", which means "trader" in Muslim language. Muslims' mass influx and their wide ranging influence on Korean society manifested from the late $13^{th}$ century when the Goryeo Dynasty first came under Mongol control and afterward in the early $15^{th}$ century with the new dynasty of Joseon in Korea.