• Title/Summary/Keyword: Wang chong

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Dimming control method for LED stage lighting system (LED 무대조명의 조도제어기법)

  • Lee, Kyu-Min;Choe, Wang-Seop;Park, Chong-Yun
    • Proceedings of the KIPE Conference
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    • 2010.11a
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    • pp.300-301
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    • 2010
  • 최근 반도체 산업의 비약적 발전으로 고출력 LED 광원 시스템 개발이 확대되고 있다. 그 중 무대조명 분야는 색 연출의 필요성으로 넓은 조도제어(Dimming) 범위가 필수적이다. 본 논문에서는 방송장비의 높은 센싱 속도로 인하여 화면에 생기는 빛의 떨림 현상 제거와 0~100%의 넓은 조도제어 범위를 구현하기 위해 Analog 조도제어와 PWM 조도제어를 결합한 조도제어 방법을 제안하였으며, 이를 위한 회로를 설계하고, 이를 실험적으로 검증하였다.

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S-Domain Equivalent System for Electromagnetic Transient Studies PART 2 : Frequency Dependent Network Equivalent (전자기 과도현상 해석을 위한 S 영역 등가시스템 PART 2 :주파수 의존 교류 시스템 등가)

  • Wang Yong P;Lee Hyun J;Chong Hyeng H;An Byung C;Kim Hae J
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.283-285
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    • 2004
  • Modern power systems are very complex and to model them completely is impractical for electromagnetic transient studies. Therefore areas outside the immediate area of interest must be represented by some form of frequency dependent equivalent. This paper presents the formulation for developing 1 & 2 port Frequency Dependent Network Equivalent (FDNE) with the instantaneous term in S-domain and illustrates its use. This 1 & 2 Port FDNE have been applied to the CIGRE Benchmark Rectifier test AC system. The electromagnetic transient package PSCAD/EMTDC is used to assess the transient response of the 1 & 2 port (FDNE) developed with Norton Equivalent network.

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Evaluating Shipping Financial Ecological Environment in Qingdao: Implications for Maritime Financial Center Policy of Busan

  • Wang, Chong;Qu, Wendi;Kim, Chi Yeol
    • Journal of Navigation and Port Research
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    • v.45 no.5
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    • pp.252-258
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    • 2021
  • Given the cyclicality, seasonality, and capital-intensiveness, the development of the shipping industry has long been contingent on corporate financing activities. As such, there have been a growing number of cities in East Asia pursuing a global maritime financial center in order to support their domestic shipping industry. However, it is widely accepted that financial services relevant to shipping in East Asia are quite under-developed compared to those of other leading maritime financial centers in Europe and North America. In this regard, this paper aimed to construct an evaluation index of maritime financial centers in terms of financial ecological environment for the purpose of highlighting the current status of development and suggesting future directions. Furthermore, this paper examined the development of shipping finance in Qingdao as a numerical example using the fuzzy comprehensive evaluation and compared results with those of Shanghai.

Fabrication of Water-Soluble CuInS2 Quantum Dots by Hot-injection Method and Phase Transfer Strategy

  • Deng, Chong;Fu, Bowen;Wang, Yanlai;Yang, Lin
    • Nano
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    • v.13 no.10
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    • pp.1850114.1-1850114.7
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    • 2018
  • Here we report an optimized hot-injection method and a phase transfer strategy for the synthesis of water-soluble $CuInS_2$ QDs with desired properties. The structure and morphology studies demonstrate that the resulting QDs are $CuInS_2$ tetragonal phase with well-defined facets. It is also found that the crystal size gradually increases with the increase of reaction temperature, while the surface of QDs with pre- and post-phase transfer is functionalized with hydrophobic and hydrophilic ligands, respectively. Spectroscopy measurements reveal the size-dependent optical properties of $CuInS_2$ QDs, demonstrating the quantum confinement effect in this system.

Numerical analysis of large stud shear connector embedded in HFRC

  • He, Yu Liang;Zhang, Chong;Wang, Li Chao;Yang, Ying;Xiang, Yi Qiang
    • Structural Engineering and Mechanics
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    • v.80 no.5
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    • pp.595-608
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    • 2021
  • To investigate the mechanical behavior of large stud shear connector embedded in hybrid fiber-reinforced concrete (HFRC), a refined 3D nonlinear finite element (FE) model incorporating the constitutive model of HFRC was developed using ANSYS. Firstly, the test results conducted by the authors (He et al. 2017) were used to validate FE model of push out tests. Secondly, a total of 27 specimens were analyzed with various parameters including fiber volume fractions of HFRC, diameter of studs and HFRC strength. Finally, an empirical equation considering the contribution of steel fiber (SF) and polypropylene fiber (PF) was recommended to estimate the ultimate capacity of large stud shear connector embedded in HFRC.

Modification of Styrene-Butadiene-Styrene Block Copolymer and the Properties of Graft Products (스티렌-부타디엔-스티렌 블록 공중합체(共重合體)의 개질(改質)과 그 특성(特性))

  • Wang, Eun-Jin;Yoon, Jeong-Sik;Yoo, Chong-Sun;Paik, Nam-Chul
    • Elastomers and Composites
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    • v.25 no.4
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    • pp.273-279
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    • 1990
  • The graft polymerization of 2-hydroxyethylmethacrylate(HEMA) and vinyltriethoxysilane(VTES) onto styrene-butadiene-styrene block copolymer(SBS) was carried out in toluene, with radical initiator such as benzoyl peroxide(BPO) and 2, 2'-azo-bis-isobutyronitrile(AIBIN) under nitrogen atmosphere. The degree of grafting was increased with the increases of the reaction temperature and time. And the effeciency of BPO was superior to that of AIBN. The mechanical properties and molecular weight of graft products were measured and the applicability as adhesive of plasticized PVC leather was examined.

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Synthesis and Characterization of banana-shaped achiral molecules

  • Lee, Chong-Kwang;Lee, Chong-Kwang;Kwon, Soon-Sik;Kim, Tae-Sung;Shin, Sung-Tae;Choi, Suk;Choi, E-Joon;Kim, Sea-Yun;Kim, Jae-Hoon;Zin, Wang-Choel;Kim, Dae-Cheol;Chien, Liang-Chy
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.504-508
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    • 2003
  • New banana-shaped achiral compounds, 4-chloro-1,3-phenylene bis [4-4(3-fluoro-9-alkenyloxy) phenyl-iminomethylbenzoate]s and 4-chloro-1,3-phenylene bis [4-4-(3-fluoro-10-alkanyloxy) phenyliminomethyl benzoate]s were synthesized by varying the substituent (X=H, F, or Cl); their electrooptical properties are described. The smectic phases, including a switchable chiral smectic C ($SmC^{\ast}$) phase, were characterized by differential scanning calorimetry, polarizing optical microscopy, and triangular method. The presence of vinyl end group at the terminals of linear side wings in the banana-shaped molecules induced a decrease in melting temperature. The smectic phase having the undecenyloxy group such $as-(CH_2)_9CH=CH_2$ showed ferroelectric switching, and its value of spontaneous polarization on reversal of an applied electric field was 2250 $nC/cm^2$, while the value of spontaneous polarization of the smectic phase having the decanyloxy group such as $-(CH2)_9CH_3$ was 3700 $nC/cm^2$. We could obtain the ferroelectric phase with low isotropic temperature by varying the end group at the terminals of linear side wings in the banana-shaped achiral molecules.

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A study on the Main Diseases of Three Divisions of the Pulse and the Symptoms of Diseases of Gi Kyoung Pal Maek(奇經八脈) of the Maek Kyoung(脈經) Vol. II (II) (맥경권제이(脈經卷第二) 삼관맥주병(三關脈主病)과 기경팔맥병증(奇經八脈病證)에 대(對)한 연구(硏究) (II))

  • Lim, Dong-Kook;Park, Kyung
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.11 no.1
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    • pp.1-24
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    • 2007
  • Maek Kyoung(Mai Jing, 脈經) is the first chinese specialized book of diagnostics written by Wang Hee(Wang xi, 王熙) from Seo Jin(xi jin, 西晉). He assorted the contents with pulse and medical examination from Nae Kyoung(nei jing, 內經), Nan Kyoung(nan jing, 難經), Sang Han Ron(shang han lun, 傷寒論) and Jung Jang Kyoung(zhong cang jing, 中藏經). And united with his own research, he explains medical examination and the way of talking the pulse by classifying into entrance and class. Maek Kyoung(Mai Jing, 脈經) was imported Korea by Ji Chong(zhi cong, 知聰) AD 561, and he passed through Ko Ku Ryeo(gao gou li, 高句麗) with Nae Wei Jeon(nei wai dian, 內外典), Yak Seo(yao shu, 藥書), Myung Dang Do(ming tang tu, 明堂圖) and Maek Kyoung(Mai Jing, 脈經) to be naturalized in Japan. This treatise make a special study of the second volume of the Maek Kyoung. It consists of the four chapters: Pyoung Sam Kwan Eum Yang E Sip Sa Ki Maek Je II(平三關陰陽二十四氣脈第一), Pyoung In Young Sin Mun Ki Ku Jeon Hu Maek Je E(平人迎神門氣口前後脈第二), Pyoung Sam Kwan Byoung Hu Byoung Chi Eui Je Sam(平三關病侯幷治宜第三), and Pyoung Gi Kyoung Pal Maek Byoung Je Sa(平寄經八脈病第四). Bi Geup Choun Geum Yo Bang(備急千金要方) and Eui Hak Ip Mun(醫學入門) quoted from the contents in the second volume of Maek Kyoung, and Bin Ho Maek Hak(瀕湖脈學), Gi Kyoung Pal Maek Go(奇經八脈攷) and Maek Eo(脈語) extracted from contents in the second volume of the Maek Kyoung and requoted from this contents. Contents in the second volume of the Maek Kyoung have very valuable data like that, but the literature on this subject in the form of a treatise has not been yet in Korea. So I hope this study will be useful to develope Diagnostics by correcting translation and interpretation and fixing wrong translation.

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Ellagic Acid Exerts Anti-proliferation Effects via Modulation of Tgf-Β/Smad3 Signaling in MCF-7 Breast Cancer Cells

  • Zhang, Tao;Chen, Hong-Sheng;Wang, Li-Feng;Bai, Ming-Han;Wang, Yi-Chong;Jiang, Xiao-Feng;Liu, Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.273-276
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    • 2014
  • Ellagic acid has been shown to inhibit tumor cell growth. However, the underlying molecular mechanisms remain elusive. In this study, our aim was to investigate whether ellagic acid inhibits the proliferation of MCF-7 human breast cancer cells via regulation of the TGF-${\beta}$/Smad3 signaling pathway. MCF-7 breast cancer cells were transfected with pEGFP-C3 or pEGFP-C3/Smad3 plasmids, and treated with ellagic acid alone or in combination with SIS3, a specific inhibitor of Smad3 phosphorylation. Cell proliferation was assessed by MTT assay and the cell cycle was detected by flow cytometry. Moreover, gene expression was detected by RT-PCR, real-time PCR and Western blot analysis. The MTT assay showed that SIS3 attenuated the inhibitory activity of ellagic acid on the proliferation of MCF-7 cells. Flow cytometry revealed that ellagic acid induced G0/G1 cell cycle arrest which was mitigated by SIS3. Moreover, SIS3 reversed the effects of ellagic acid on the expression of downstream targets of the TGF-${\beta}$/Smad3 pathway. In conclusion, ellagic acid leads to decreased phosphorylation of RB proteins mainly through modulation of the TGF-${\beta}$/Smad3 pathway, and thereby inhibits the proliferation of MCF-7 breast cancer cells.

The Effects of Different Substrates on the Growth, Yield, and Nutritional Composition of Two Oyster Mushrooms (Pleurotus ostreatus and Pleurotus cystidiosus)

  • Hoa, Ha Thi;Wang, Chun-Li;Wang, Chong-Ho
    • Mycobiology
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    • v.43 no.4
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    • pp.423-434
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    • 2015
  • The study was conducted to compare the effects of different agro-wastes on the growth, yield, and nutritional composition of oyster mushrooms Pleurotus ostreatus (PO) and Pleurotus cystidiosus (PC). Seven substrate formulas including sawdust (SD), corncob (CC), sugarcane bagasse (SB) alone and in combination of 80 : 20, 50 : 50 ratio between SD and CC, SD and SB were investigated. The results indicated that different substrate formulas gave a significant difference in total colonization period, characteristics of fruiting bodies, yield, biological efficiency (BE), nutritional composition and mineral contents of two oyster mushrooms PO and PC. The results showed that increasing CC and SB reduced C/N ratio, and enhanced some mineral contents (Ca, P, and Mg) of substrate formulas. The increased amount of CC and SB of substrate formulas enhanced protein, ash, mineral contents (Ca, K, Mg, Mn, and Zn) of fruiting bodies of both mushrooms. Substrates with 100% CC and 100% SB were the most suitable substrate formulas for cultivation of oyster mushrooms PO and PC in which they gave the highest values of cap diameter, stipe thickness, mushroom weight, yield, BE, protein, fiber, ash, mineral content (Ca, K, and Mg) and short stipe length. However, substrate formula 100% CC gave the slowest time for the first harvest of both mushrooms PO and PC (46.02 days and 64.24 days, respectively). It is also found that the C/N ratio of substrate formulas has close correlation with total colonization period, mushroom weight, yield, BE and protein content of mushroom PO and PC.