• 제목/요약/키워드: Components

검색결과 35,036건 처리시간 0.053초

External Cavity Lasers Composed of Higher Order Gratings and SLDs Integrated on PLC Platform

  • Shin, Jang-Uk;Oh, Su-Hwan;Park, Yoon-Jung;Park, Sang-Ho;Han, Young-Tak;Sung, Hee-Kyung;Oh, Kwang-Ryong
    • ETRI Journal
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    • 제29권4호
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    • pp.452-456
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    • 2007
  • Very compact 4-channel 200-GHz-spacing external cavity lasers (ECLs) were fabricated by hybrid integration of reflection gratings and superluminescent laser diodes on a planar lightwave circuit chip. The fifth-order gratings as reflection gratings were formed using a conventional contact-mask photo-lithography process to achieve low-cost fabrication. The lasing wavelength of the fabricated ECLs matched the ITU grid with an accuracy of ${\pm}0.1$ nm, and optical powers were more than 0.4 mW at the injection current of 80 mA for all channels. The ECLs showed single mode operations with more than 30 dB side lobe suppression.

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Immunomodulatory activity of Salicornia herbacea L. Components

  • Im, Sun-A;Kim, Goo-Whan;Lee, Chong-Kil
    • Natural Product Sciences
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    • 제9권4호
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    • pp.273-277
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    • 2003
  • Salicornia herbacea is an annual herb growing in salt marshes and on muddy seashores. Salicornia herbacea has been used as a fork medicine as well as a seasoned vegetable. In fork medicine, Salicornia herbacea has been used to treat a variety of diseases such as constipation, obesity, diabetes, asthma, arthritis and cancer. However, the biological mechanisms for these activities have not been characterized, nor the active components. The immunomodulatory activity of Salicornia herbacea components were studied in the present study. The components of Salicornia herbacea were prepared from the whole plant by passage through a fine screen, and then dialyzed against PBS overnight. Immunomodulatory activities of the Salicornia herbacea components were examined on a mouse macrophage cell line, RAW 264.7 cells. The Salicornia herbacea components were shown to stimulate cytokine production, nitric oxide release, and expression of surface molecules in a dose dependent manner. The Salicornia herbacea components also induced further differentiation of slightly adherent RAW 264.7 cell into strongly adherent macrophages. These results indicate that Salicornia herbacea contains immunomodulator(s) that induces activation of macrophages.

유지식품의 조리 중 기능성분의 변화 (Changes of Functional Components Present in Lipid Foods during Cooking)

  • 최은옥
    • 한국식품조리과학회지
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    • 제21권5호
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    • pp.742-758
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    • 2005
  • Lipid-based functional components present in foods undergo chemical changes during cooking. Useful n-3 and n-6 fatty acids, phytosterols, tocopherols, and carotenoids are degraded by thermal cooking such as frying, resulting in loss of their physiological functions. However, conjugated linoleic acid and diacylglycerols can be formed during heating, which would be beneficial to the health. Degree of degradation and formation of the functional components depends on the cooking method, cooking temperature and time, lipid matrix containing the components, and the presence of other materials. Although it is clear that the content of each functional component varies during long-heating in a model system consisting of small numbers of components, the real foods cooked in a small scale for a limited cooking time do not show highly significant differences in the functional components contents from raw food materials.

Structure-related Characteristics of SiGe HBT and 2.4 GHz Down-conversion Mixer

  • Lee, Sang-Heung;Kim, Sang-Hoon;Lee, Ja-Yol;Bae, Hyun-Cheol;Lee, Seung-Yun;Kang, Jin-Yeong;Kim, Bo-Woo
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권2호
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    • pp.114-118
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    • 2006
  • In this paper, the effect of base and collector structures on DC, small signal characteristics of SiGe HBTs fabricated by RPCVD was investigated. The structure of SiGe HBTs was designed into four types as follows: SiGe HBT structures which are standard, apply extrinsic-base SEG selective epitaxial growth (SEG), apply selective collector implantation (SCI), and apply both extrinsic-base SEG and SCI. We verified the devices could be applied to the fabrication of RFIC chip through a fully integrated 2.4 GHz down-conversion mixer.

마스크 데이터를 이용한 컴포넌트의 고장발생확률 추정 (Estimating Outbreak Probabilities of Systems and Components with Masked Data)

  • 박창규
    • 산업경영시스템학회지
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    • 제25권6호
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    • pp.7-11
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    • 2002
  • This paper estimates defect and outbreak probabilities of each individual component from some subset of masked data where the exact component causing system failure might be unknown. A system consists of k components that fails whenever there is a defect in at least one of the components. Due to cost and time constraints it is not feasible to learn exactly which components are defective. Because, test procedures ascertain that the defective components belong to some subset of the k components. This phenomenon is termed masking. We describe a, b, c type in which a sample of masked subsets is subjected to intensive failure analysis. This recorded data of a, b, c type enables maximum likelihood estimation of defect probability of each individual component and leads to outbreak of the defective components in future masked failures.

Temperature, Current, and Voltage Dependences of Junction Failure in PIN Photodiodes

  • Park, Sahng-Gi;Sim, Eun-Deok;Park, Jeong-Woo;Sim, Jae-Sik;Song, Hyun-Woo;Oh, Su-Hwan;Baek, Yong-Soon
    • ETRI Journal
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    • 제28권5호
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    • pp.555-560
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    • 2006
  • A PIN photodiode having a low dark current of 1.35 nA and a high external quantum efficiency of 95.3% fabricated for a passive optical network receiver. As the current was increased under a high voltage of 38 V and a temperature of $190^{\circ}C$, it was observed that there is a threshold current at 11 mA which induces a junction failure. Experimental data suggest that the junction failure occurs due to the crystal breaking at the end facet as a result of thermal heat or energetic carriers. This threshold behavior of junction failure is a valuable observation for the safe treatment of photodiodes. As long as the current is limited below the threshold currents, we have not observed failure events of our photodiodes.

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가변 대역폭 필터를 이용한 음성신호의 AM-FM 성분 분리에 관한 연구 (Decomposition of Speech Signal into AM-FM Components Using Varialle Bandwidth Filter)

  • 송민;이희영
    • 음성과학
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    • 제8권4호
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    • pp.45-58
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    • 2001
  • Modulated components of a speech signal are frequently used for speech coding, speech recognition, and speech synthesis. Time-frequency representation (TFR) reveals some information about instantaneous frequency, instantaneous bandwidth and boundary of each component of the considering speech signal. In many cases, the extraction of AM-FM components corresponding to instantaneous frequencies is difficult since the Fourier spectra of the components with time-varying instantaneous frequency are overlapped each other in Fourier frequency domain. In this paper, an efficient method decomposing speech signal into AM-FM components is proposed. A variable bandwidth filter is developed for the decomposition of speech signals with time-varying instantaneous frequencies. The variable bandwidth filter can extract AM-FM components of a speech signal whose TFRs are not overlapped in timefrequency domain. Also, amplitude and instantaneous frequency of the decomposed components are estimated by using Hilbert transform.

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배초향 잎의 유용성분과 특성 (Characteristics of Useful Components in the Leaves of Baechohyang(Agastache rugosa, O. Kuntze))

  • 최갑성;이홍열
    • 한국식품영양과학회지
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    • 제28권2호
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    • pp.326-332
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    • 1999
  • In order to develope useful components and to apply in food additives, various components in the leaves of baechohyang were determined according to picking date. Moisture and ash were reached to 74~82%, 1.5~3.4%, respectively, and major sugars were fructose, glucose, sucrose, and maltose. Glutamic, aspartic acid, and leucine constituted the main component amino acids and their contents were relatively higher in the samples of summer and young leaves. Among free amino acids, histidine showed the highest components and methionine were the lowest. Potassium, calcium, and sodium were main mineral components. The content of ascorbic acid were 6.6~9.2mg% and seasonal variations were negligible. Muture leaves contained more polyphenols as much as 108~181mg% and the amount of bound fractions were much more. Periodic evaluation of phenolic compounds were made and major components of bound fractions were caffeic, syringic, and ferulic acid.

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Supporting Java Components in the SID Simulation System

  • Ma'ruf, Hasrul;Febiansyah, Hidayat;Kwon, Jin-Baek
    • Journal of Information Processing Systems
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    • 제8권1호
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    • pp.101-118
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    • 2012
  • Embedded products are becoming richer in features. Simulation tools facilitate low-costs and the efficient development of embedded systems. SID is an open source simulation software that includes a library of components for modeling hardware and software components. SID components were originally written using C/C++ and Tcl/Tk. Tcl/Tk has mainly been used for GUI simulation in the SID system. However, Tcl/Tk components are hampered by low performance, and GUI development using Tcl/Tk also has poor flexibility. Therefore, it would be desirable to use a more advanced programming language, such as Java, to provide simulations of cutting-edge products with rich graphics. Here, we describe the development of the Java Bridge Module as a middleware that will enable the use of Java Components in SID. We also extended the low-level SID API to Java. In addition, we have added classes that contain default implementations of the API. These classes are intended to ensure the compatibility and simplicity of SID components in Java.

New Impedance Matching Scheme for 60 GHz Band Electro-Absorption Modulator Modules

  • Choi, Kwang-Seong;Chung, Yong-Duck;Kang, Young-Shik;Jun, Dong-Suk;Ahn, Byoung-Tae;Moon, Jong-Tae;Kim, Je-Ha
    • ETRI Journal
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    • 제28권3호
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    • pp.393-396
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    • 2006
  • This letter proposes a new impedance matching scheme of a traveling wave electro-absorption modulator (TWEAM) module for a 60 GHz band radio-over-fiber (ROF) link. A microstrip band pass filter (BPF) was used to achieve impedance matching at the 60 GHz band, and termination resistance was carefully designed to obtain an input impedance close to $50\;{\Omega}$. Also, a bias circuit for the device was designed in the module. The measured return loss and frequency response show that the modulator module observes the characteristics of a filter without the need of a further tuning process.

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