• Journal of the Korean Institute of Gas
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• v.4 no.4 s.12
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• pp.1-5
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• 2000

Cubic and non-cubic equations of state are used to calculate the vapor-liquid equilibrium(VLE) compositions for liquified natural gas(LNG) containing hydrogen sulfide. Modified Benedict-Web-Robin EOS is chosen as a non-cubic equation of state while Peng-Robinson, Soave-Redlich-Kwong EOS are used for a cubic EOS. Modified Benedict-Web-Robin EOS. showed better predictability than the cubic EOS used for the systems $H_2S/CH_4,\;H_2S/iC_4H_{10},\;H_2S/N_2$. specially for liquid composition.

• Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.10.1-10.5
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• 2016

Setarches longimanus (Alcock 1894), in the family Scorpaenidae, was collected from Busan and the coastal waters of Jeju Island, Korea, in January and November 2014, respectively. Two specimens are characterized by XI, 10 dorsalfin rays; 19-21 pectoralfin rays; III, 5 anal fin rays; a second preopercular spine much shorter than the first and third; and an interorbital width 11.3 %-11.6 % of the standard length. We also analyzed 587 base pairs of the mitochondrial DNA cytochrome c oxidase subunit I sequences in order to confirm the taxonomic status of the specimen. As a result, the sequences of our specimen almost corresponded to those of Chinese S. longimanus (genetic distance, d = 0.005), but considerably differed from those of S. guentheri (d = 0.120-0.124). We propose the new Korean names "Ma-su-gam-peng-sok" for the genus Setarches, and "Bul-geun-ma-su-gam-peng" for the species S. longimanus.

• Journal of ILASS-Korea
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• v.2 no.3
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• pp.32-43
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• 1997

A comparison of predicted molar volume, vapor - liquid equilibrium, enthalpy of vaporization, droplet size history. and vaporization rates with several forms of equation of state has been made. The equation of state (EOS) investigated in this study includes the EOS given by Redlich - Kwong, the Soave - Redlich - Kwong, and the Peng - Robinson. Numerical results indicate that the Peng - Robinson EOS yields more accurate predictions of vapor - liquid equilibrium under a broader range of temperature and pressure conditions, especially at high pressures and near the critical point.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.34-43
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• 2007

In the IEEE 802.15.3 Medium Access Control (MAC) protocol, Simultaneously Operating Piconets (SOPs) are linked by the parent/child (P/C) or parent/neighbor (P/N) configuration, which work on a Time Division Multiple Access (TDMA) basis. This provides interference mitigation but the overall throughput is limited because the SOPs share the channel time exclusively. The protocol is not efficient for SOPs if we focus on the combination of interference mitigation and high throughput maintenance. In this paper Public Channel Time Allocation (Public CTA) is proposed, which is able to greatly reduce the inter-piconet interference (IPI) and achieve greater throughput without much loss of link success probability (LSP) in the SOPs. The simulation results based on the SOPs of Direct Sequence Ultra Wideband (DS-UWB) system demonstrate that the proposed scheme effectively supports the coexistence of SOPs, and it can not only significantly improve the overall throughput of SOPs but also maintain high LSP.

• Journal of Power Electronics
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• v.19 no.2
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• pp.443-453
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• 2019

As the core component of transmission systems, converters are very prone to failure. To improve the accuracy of fault diagnosis for wind power converters, a fault feature extraction method combined with a wavelet transform and compressed sensing theory is proposed. In addition, an improved AdaBoost-SVM is used to diagnose wind power converters. The three-phase output current signal is selected as the research object and is processed by the wavelet transform to reduce the signal noise. The wavelet approximation coefficients are dimensionality reduced to obtain measurement signals based on the theory of compressive sensing. A sparse vector is obtained by the orthogonal matching pursuit algorithm, and then the fault feature vector is extracted. The fault feature vectors are input to the improved AdaBoost-SVM classifier to realize fault diagnosis. Simulation results show that this method can effectively realize the fault diagnosis of the power transistors in converters and improve the precision of fault diagnosis.

• Current Optics and Photonics
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• v.7 no.4
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• pp.463-470
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• 2023

Hydroxygraphene as a kind of functionalized graphene has important applications in composite, photoelectric and biological materials. In the present study, THz and microfluidic technologies were implemented to study the THz transmission characteristics of hydroxygraphene with different concentrations and residence times in magnetic and electric fields. The results show that the THz transmission intensity decreases with the increase in sample concentration and duration of an applied electric field, while it increases by staying longer in the magnetic field. The phenomenon is analyzed and explained in terms of hydrogen bond, conductivity and scattering characteristics. The results establish a foundation for future research on the THz absorption characteristics of liquid graphene based on microfluidic technology in different external environments. It also provides technical support for the application and development of graphene in THz devices.

• The Korean Journal of Zoology
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• v.17 no.2
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• pp.103-105
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• 1974

D. auraria Peng은 Okada등에 의하여 주로 生殖器의 形態的 差異로 A, B, C, 3品種으로 分類되어 왔으나 1972年 Bock & Wheeler에 의하여 A品種은 D. auraria Peng으로, B品種은 D. biauraria, C品種은 D. triauraria로 命名되었는데 이들 3品種은 우리나라에 널리 分布되어 있다. 種分化 過程의 硏究의 一端으로 이 種群에 속하는 台灣産 D. quadraria를 합하여 4種에 대한 外部形態의 比較와 各 種間雜種에 대한 外部形態를 比較 檢討하였다. 外部形態로서는 1) 翅長과 翅脈指數 2) 수컷의 第六腹筋剛毛數 3) 生殖器(phallic organ, periphallic organ, egg guide)를 주로 調査하였다. 1. 翅長과 翅脈指數 調査에서 4種間의 特徵이 뚜렷하였고 種間雜種에서는 大體로 兩種間의 中間値를 나타냈다. 한편 翅脈特徵인 Sturtevant 法則과 Burla 法則에 一致함을 확인했다. 2. 수컷의 腹部剛毛의 平均値는 D. auraria는 $15.36 \\pm 0.301$, D. triauraria는 $11.65 \\pm 0.42$, D. quadraria는 $10.16 \\pm 0.23$이였고, D. biauraria는 剛毛가 全혀 없다. 이들의 剛毛의 遺傳은 polygene에 의하여 支配되는 것이라고 생각된다. 3. 生殖器의 特徵은 4種間에 뚜렷이 區別되나 種間雜種에 있어서는 形態에 있어서 大體로 中間型을 나타냈다.

• Industrial Engineering and Management Systems
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• v.11 no.2
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• pp.133-133
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• 2012

• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.82.4-82.4
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• 2008

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1299-1300
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• 2005