• Title/Summary/Keyword: compound system

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Angle-sensitive Pixels Based on Subwavelength Compound Gratings

  • Meng, Yunlong;Hu, Xuemei;Yang, Cheng;Shen, Xinyu;Cao, Xueyun;Lin, Lankun;Yan, Feng;Yue, Tao
    • Current Optics and Photonics
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    • v.6 no.4
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    • pp.359-366
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    • 2022
  • In this paper, we present a new design for angle-sensitive pixels (ASPs). The proposed ASPs take advantage of subwavelength compound gratings to capture the light angle, which enables pixel size to reach the wavelength scale of 0.7 ㎛ × 0.7 ㎛. The subwavelength compound gratings are implemented by the wires of the readout circuit inherent to the standard complementary metal-oxide-semiconductor manufacturing process, thus avoiding additional off-chip optics or post-processing. This technique allows the use of two pixels for horizontal or vertical angle detection, and can determine the light's angle in the range from -45° to +45°. The proposed sensor enables surface-profile reconstruction of microscale samples using a lensless imaging system.

A study on the significance and structural improvement of the stone chamber tomb by the application of a compound lime - Mortar during the reign of king Sejong in the Joseon Dynasty (조선 세종대 삼물회(三物灰) 도입에 따른 석실릉 구조개선과 의의)

  • SHIN, Jihye
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.223-242
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    • 2022
  • The main purpose of this study is to find out the meaning of structural changes that appeared in the royal tombs of the Joseon Dynasty after the application of a compound lime-mortar(Sammulhoe三物灰: the mortar with lime, sand, ocher). In the early Joseon Dynasty, the royal tomb was constructed by following the system of the stone chamber tomb in the Goryeo Dynasty. However the system of the stone chamber tomb recorded in 『GukJo-OReYi(國朝五禮儀: The five category's formalities in the Joseon Dynasty)』 is very different from that in the Goryeo Dynasty. The biggest difference is that a compound lime-mortar was applied into the system of the stone chamber tomb in order to attempt structural reinforcement. This change reflects King Sejong's willingness to build a dense structure in which water does not permeate the stone chamber when Yeongneung(英陵) was built in 1446(the 28th year of King Sejong's reign). Yeongneung is a complex structure consisting of a stone chamber and compound lime-mortar wall. After constructing a stone chamber, the 1.2m(4尺) thick wall with a compound lime-mortar is additionally constructed outside the stone chamber structure. In 1468(the year of King Yejong's accession), according to the will of King Sejo, the stone chamber system was abolished and the Hyeongung(玄宮: the chamber enshrining a coffin of the deceased king or queen consort) was constructed only by the thick wall with a compound lime-mortar. This change become a primary cause for the royal tomb to be constructed as Hoekyukneung(灰隔陵: the royal tomb with chamber constructed only by the thick wall with compound lime-mortar) in the late Joseon Dynasty. The Hoekyukneung in the late Joseon Dynasty has been constructed with the method of structure and construction for the thick wall with a compound lime-mortar since the complex structure recorded in 『GukJo-OReYi(國朝五禮儀)』. The Hoekuykseoksilneung(灰隔石室陵: the complex structure consisting of a stone chamber and compound lime-mortar wall) is unique tomb style of Joseon Dynasty and become a motive of tomb system(Hoekuykneung) in the late Joseon Dynasty.

Analysis of the Efficiency of the Compound-split Hybrid Systems (복합 유성 기어로 구성된 하이브리드 시스템 효율 분석)

  • Kim, Nam-Wook;Yang, Ho-Rim;Cho, Sung-Tae;Park, Yeong-Il;Cha, Suk-Won
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.5
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    • pp.118-124
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    • 2007
  • The efficiency of the hybrid systems which are composed of compound planetary gear sets depend on the amount of the recirculating energy among the motors and battery. This paper studies the analysis of the system efficiency with the parameters, ${\alpha},\;{\beta},\;{\gamma_a},\;{\gamma_b}$ and $\gamma_s$. The efficiency of the systems and the relative torque, speed and power of the power resources are represented by these parameters. The recuperating parameter $\kappa$ which makes the systems generalized is introduced, so the efficiencies of the modes such as the hybrid mode, the engine mode, the motoring mode and the recuperating mode are analyzed with simple equations. The tendency of the system efficiency according to the variations of the $\gamma_s$ and $\kappa$ are studied, by which it can be possible to reduce the loss of the power because the strategies for avoiding the singular speed ratio $\gamma_s$ are helpful for the system efficiency and specific value of $\kappa$ can increase the efficiency of the systems.

Study on the Performance of Fuel Cell Driven Compound Source Heat Pump System to a Large Community Building (대형 Community 건물의 연료전지 구동 복합열원 하이브리드 히트펌프 시스템 성능에 관한 해석적 연구)

  • Jeong, Dong-Hwa;Byun, Jae-Ki;Choi, Young-Don;Cho, Sung-Hwan
    • New & Renewable Energy
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    • v.4 no.3
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    • pp.23-35
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    • 2008
  • In the present study, performances of fuel cell driven compound source hybrid heat pump system applied to a large community building are simulated. Among several renewable energy sources, ground, river, sea, and waste water sources are chosen as available alternative energies. The performance and energy cost are varied with the hybrid heat pump sources. The system design and operation process appropriate for the surrounding circumstance guarantee the high benefit of the heat pump system applied to a large community building. Th system is driven by fuel cell system instead of the late-night electricity due to the advantages of the low energy cost and waste heat with high temperature.

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Order Based Performance Evaluation of a CONWIP System with Compound Poisson Demands (복합포아송 수요를 가지는 CONWIP 시스템에서 고객집단의 성능평가)

  • Park Chan-U;Lee Hyo-Seong
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.10a
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    • pp.8-12
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    • 2004
  • In this study we consider a CONWIP system in which the processing times at each station follow a Coxian distribution and the demands for the finished products arrive according to a compound Poisson process. The demands that are not satisfied are backordered according to the number of demands that exist at their arrival instants. For this system we develop an approximation method to calculate order based performance measures such as the mean time of fulfilling a customer order and the mean number o: customer orders. For the analysis of the proposed CONWIP system, we model the CONWIP system as a closed queueing network with a synchronization station and analyze the closed queueing network using a product form approximation method. Numerical tests show that the approximation method provides fairly good estimation of the performance measures of interest.

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Ab Initio and Experimental Studies on Dibenzothiazyl-Disulfide

  • Jian, Fang-Fang;Zhang, Ke-Jie;Zhao, Pu-Su;Zheng, Jian
    • Bulletin of the Korean Chemical Society
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    • v.27 no.7
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    • pp.1048-1052
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    • 2006
  • Ab initio calculations of the structure, atomic charges and natural bond orbital (NBO) have been performed at HF/6-311G** and B3LYP/6-311G** levels for the title compound of dibenzothiazyl-disulfide. The calculated results show that the two nitrogen atoms have the biggest negative charges and they are the potential sites to react with the metallic ions, which make the title compound become a di-dentate ligand. Vibrational frequencies of the title compound have been obtained and compared with the experimental value and the comparison indicates that B3LYP/6-311G** level is better than HF/6-311G** level to predict the vibrational frequencies for the system studied here. For the title compound, electronic absorption spectra calculated by time?ependent density functional theory (TD-DFT) are more accurate than Hartree-Focksingle-excitation CI (CI-Singles) method. NBO analyses show that the electronic transitions are mainly derived from the contribution of bands $\pi\rightarrow\pi^{*}$. Thermodynamic calculated results show that the formation of the title compound from 2-mercaptobenzothiazole is a spontaneous process at room temperature with the change of free Gibbs being negative value.

Investigation of Al-hydroxide Precipitate Fouling on the Nanofiltration Membrane System with Coagulation Pretreatment: Effect of Inorganic Compound, Organic Compound, and Their Combination

  • Choi, Yang-Hun;Kweon, Ji-Hyang
    • Environmental Engineering Research
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    • v.16 no.3
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    • pp.149-157
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    • 2011
  • Nanofiltration (NF) experiments were conducted to investigate fouling of Al-hydroxide precipitate and the influence of organic compound, inorganic compound, and their combination, i.e., multiple foulants. $CaCl_2$ and $MgSO_4$ were employed as surrogates of inorganic compounds while humic acid was used as surrogate of organic compound. The flux attained from NF experiments was fitted with the mathematical fouling model to evaluate the potential fouling mechanisms. Al-hydroxide fouling with a cake formation mechanism had little effect on the NF membrane fouling regardless of the Al concentration. The NF fouling by Al-hydroxide precipitate was deteriorated in presence of inorganic matter. The effect of Mg was more critical in increasing the fouling than Ca. This is because the Mg ions enhanced the resistances of the cake layer accumulated by the Al-hydroxide precipitate on the membrane surfaces. However, the fouling with Mg was dramatically mitigated by adding humic acid. It is interesting to observe that the removal of the conductivity was enhanced to 61.2% in presence of Mg and humic acid from 30.9% with Al-hydroxide alone. The influence of dissolved matter (i.e., colloids) was more negative than particulate matter on the NF fouling for Al-hydroxide precipitate in presence of inorganic and organic matter.

Voltage Control of a Synchronous Generator for Ship using a Compound Type Digital AVR (혼합형 디지털 자동 전압 조정 장치를 이용한 선박용 동기발전기의 출력전압제어)

  • Park, Sang-Hoon;Lee, Sang-Seuk;Yu, Jae-Sung;Lee, Su-Won;Won, Chung-Yuen
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.4
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    • pp.397-403
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    • 2009
  • In this paper, an exciter current control of a synchronous generator for ships using a compound type digital automatic voltage regulator (DVAR) in order to provide a constant output voltage of the generator is presented. The compound type DAVR is composed of a controller part to adjust output voltage and an power source unit to supply power to the exciter. The controller part, which generates the PWM switching pattern via the PI controller, drives a power MOSFET for bypass to limit the SG's exciter current. The power source unit part is parallel connected to an output terminal of the generator through a reactor and a power CT. The residual magnetic flux of SG provides exciter current to the exciter through the reactor during the initial running or no load state and load current supplies field current to the exciter through the power CT during loading state. This paper confirmed an experiment to verify the validity of compound type DAVR system for controlling output voltage of synchronous generator.

INTERFACIAL REACTIONS BETWEEN SN-58MASS%BI EUTECTIC SOLDER AND (CU, ELECTROLESS NI-P/CU)SUBSTRATE

  • Yoon, Jeong-Won;Lee, hang-Bae;Park, Guang-Jin;Shin, Young-Eui;Jung, Seung-Boo
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.487-492
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    • 2002
  • The growth kinetics of intermetallic compound layers formed between eutectic Sn-58Bi solder and (Cu, electroless Ni-P/Cu) substrate were investigated at temperature between 70 and 120 C for 1 to 60 days. The layer growth of intermetallic compound in the couple of the Sn-58Bi/Cu and Sn-58Bi/electroless Ni-P system satisfied the parabolic law at given temperature range. As a whole, because the values of time exponent (n) have approximately 0.5, the layer growth of the intermetallic compound was mainly controlled by volume diffusion over the temperature range studied. The apparent activation energies of Cu$_{6}$Sn$_{5}$ and Ni$_3$Sn$_4$ intermetallic compound in the couple of the Sn-58Bi/Cu and Sn-58Bi/electroless Ni-P were 127.9 and 81.6 kJ/mol, respectively.ely.

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The Protective Effect of Lentinus Edodes on Mast Cell-Mediated Immediate-Type Hypersensitivity (비만세포 매개 즉시형 과민반응에 대한 표고버섯 추출물의 보호 효과)

  • Yan, Guanghai;Choi, Yun Ho
    • Korean Journal of Pharmacognosy
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    • v.50 no.3
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    • pp.175-184
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    • 2019
  • Mast cells are crucial as effector cells in the immediate-type allergic reaction. Lentinus edodes has been the popular edible mushroom in oriental countries and reported to have immunomodulatory, anti-tumor, anti-atherogenic, anti-viral, and anti-allergic activities. However, the roles of L. edodes in mast cell-mediated anaphylactic reaction have not been fully elucidated. In this research, we have demonstrated the effects of the methanol extract of L. edodes (MELE) on mast cell-mediated anaphylaxis-like and anaphylactic reactions. MELE suppressed systemic anaphylaxis-like reaction, plasma histamine levels, and ear swelling response in mice treated with compound 48/80. MELE also suppressed passive systemic and cutaneous anaphylaxis mediated by anti-dinitrophenyl IgE. In accordance with these findings, MELE dose-dependently decreased histamine release from RPMC evoked by compound 48/80 or the antigen-antibody reaction. To clarify the mechanism of degranulation system, intracellular cAMP levels as well as calcium influx in RPMC was evaluated. In compound 48/80-treated RPMC, MELE blocked calcium uptake into the cells. In addition, MELE elevated the intracellular cAMP content and significantly attenuated compound 48/80-induced cAMP reduction in RPMC. Taken together, we propose the clinical use of MELE in mast cell-mediated immediate-type allergic diseases.