• Title/Summary/Keyword: DDQ

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Fast built-in current sensor for $\textrm{I}_{DDQ}$ testing ($\textrm{I}_{DDQ}$ 테스팅을 위한 빠른 재장형 전류감지기)

  • 임창용;김동욱
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.811-814
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    • 1998
  • REcent research about current testing($\textrm{I}_{DDQ}$ testing) has been emphasizing that $\textrm{I}_{DDQ}$ testing in addition to the logical voltage testing is necessary to increase the fault coverage. The $\textrm{I}_{DDQ}$. testing can detect physical faults other than the classical stuck-at type fault, which affect reliability. One of the most critical issues in the $\textrm{I}_{DDQ}$ testing is to insert a built-in current sensor (BICS) that can detect abnormal static currents from the power supply or to the ground. This paper presents a new BICS for internal current testing for large CMOS logic circuits. The proposed BICS uses a single phase clock to minimize the hardware overhead. It detects faulty current flowing and converts it into a corresponding logic voltage level to make converts it into a corresponding logic voltage level to make it possible to use the conventional voltage testing techniqeus. By using current mirroring technique, the proposed BICS can work at very high speed. Because the proposed BICS almost does not affects normal operation of CUT(circuit under test), it can be used to a very large circuit without circuit partitioning. By altenating the operational modes, a circuit can be $\textrm{I}_{DDQ}$-tested as a kind of self-testing fashion by using the proposed BICS.

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A Test Input Sequence for Test Time Reduction of $I_{DDQ}$ Testing

  • Ohnishi, Takahiro;Yotsuyanagi, Hiroyuki;Hashizume, Masaki;Tamesada, Takeomi
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.367-370
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    • 2000
  • It is shown that $I_{DDQ}$ testing is very useful for shipping fault-free CMOS ICs. However, test time of $I_{DDQ}$ testing is extremely larger than one of logic testing. In this paper, a new test input sequence generation methodology is proposed to reduce the test time of $I_{DDQ}$ testing. At first, it is Shown that $I_{DDQ}$ test time Will be denominated by charge supply current for load capacitance of gates whose output logic values are changed by test input vector application and the charge current depends on input sequence of test vectors. After that, a test input sequence generation methodology is proposed. The feasibility is checked by some experiments.riments.

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Analysis of Distributed DDQ for QoS Router

  • Kim, Ki-Cheon
    • ETRI Journal
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    • v.28 no.1
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    • pp.31-44
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    • 2006
  • In a packet switching network, congestion is unavoidable and affects the quality of real-time traffic with such problems as delay and packet loss. Packet fair queuing (PFQ) algorithms are well-known solutions for quality-of-service (QoS) guarantee by packet scheduling. Our approach is different from previous algorithms in that it uses hardware time achieved by sampling a counter triggered by a periodic clock signal. This clock signal can be provided to all the modules of a routing system to get synchronization. In this architecture, a variant of the PFQ algorithm, called digitized delay queuing (DDQ), can be distributed on many line interface modules. We derive the delay bounds in a single processor system and in a distributed architecture. The definition of traffic contribution improves the simplicity of the mathematical models. The effect of different time between modules in a distributed architecture is the key idea for understanding the delay behavior of a routing system. The number of bins required for the DDQ algorithm is also derived to make the system configuration clear. The analytical models developed in this paper form the basis of improvement and application to a combined input and output queuing (CIOQ) router architecture for a higher speed QoS network.

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Selective Tandem Synthesis of Oximes from Benzylic Alcohols Catalyzed with 2, 3-Dichloro-5, 6-dicyanobenzoquinone

  • Aghapour, Ghasem;Mohamadian, Samaneh
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1209-1212
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    • 2012
  • In spite of many reports in the literature concerning with oxidation of benzylic alcohols to carbonyl compounds with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in stoichiometric amounts or even more, we surprisingly found that benzylic alcohols are directly oxidized to oximes using a catalytic amount of DDQ in the presence of hydroxylamine hydrochloride under solvent-free conditions. The present tandem catalytic method can be efficiently used for preparation of oximes in the presence of some other functional groups with excellent chemoselectivity.

Novel Conversion of 2-(4-Dimethylaminoaryl)-1,4-diphenylbutane-l,4-diones into 3-(4- Dimethylaminoaryl)-l-phenylpropenones via Debenzoylation and Oxidation

  • Kim, Sung-Sik;Chang, Ji-Ae;Kim, Ae-Rhan;Cho, Kyung-Won;Park, Sang-Kyu
    • Journal of Photoscience
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    • v.12 no.2
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    • pp.109-111
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    • 2005
  • It was found that 1,4-diketones such as 1,4-diphenyl-l,4-butanediones containing N,N-dimethylaminophenyl (pDPB) and N,N-dimethylaminonaphthyl (nDPB) at C2 are converted into 3-(4-dimethylaminoaryl)-1-phenylpropan-lones (pPPA and nPPA) by treatment with $Ca(OH)_2$ in methanol, which was easily oxidized to enone, i.e., 3-(4-dimethylaminophenyl)-l-phenylpropenones (pPPE and nPPE), when treated with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone (DDQ) in dichloromethane.

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Spectrophotometric Determination of Allopurinol Drug in Tablets: Spectroscopic Characterization of the Solid CT Complexes

  • Refat, Moamen S.;Mohamed, Gehad G.;Fathi, Ahmed
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1535-1542
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    • 2010
  • Spectrophotometric micro determination of allopurinol (ALP) via charge-transfer formation is described. This includes the utility of some $\pi$-acceptors such as 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (p-CLA) for estimation of ALP drug (act as $\grave{e}$-donor). These reactions are applied for determination of ALP in its pharmaceutical preparations coming from different companies. Elucidation of the chemical structure of the solid CT complexes formed via reaction between drugs under study and $\pi$-acceptors, using elemental analyses (C, H, N), I. R., $^1H$ NMR and mass spectrometry.

Structural Analysis of Water Soluble Lignin-Carbohydrate Complex(LCC) Isolated from Korean Camellia Mistletoe(Pseudixus japonicus Hayata) (한국산 동백나무겨우살이에서 추출한 수용성 리그닌-탄수화물 복합체의 구조분석)

  • Choi, Joon-Weon;Ahn, Won-Yung
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.3
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    • pp.1-7
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    • 1997
  • 한국산 동백나무겨우살이(Pseudixus japonicus Hayata)에 존재하는 수용성 리그닌-탄수화물 복합체를 구성하는 다당류의 구조를 밝히고 리그닌 성분과 다당류의 결합양식을 구명하고자, 냉 온수 추출한 수용성 리그닌-탄수화물 복합체(M-LCC-WE)를 DEAE Sephadex A-50로 중성분획(M-LCC-N)과 산성분획(M-LCC-A), 나머지분획(M-LCC-R)으로 세분화한 후 M-LCC-N과 M-LCC-A에 대하여 메틸화, 아세틸화, 그리고 DDQ 산화반응을 실시하였다. M-LCC-N을 구성하는 다당류는 ($1{\rightarrow}4$) 글리코시드결합의 arabinan과 ($1{\rightarrow}4$)나 ($1{\rightarrow}6$) 글리코시드결합의 galactan과 glucan으로 M-LCC-A의 다당류는 ($1{\rightarrow}4$) 글리코시드결합의 arabinan과 ($1{\rightarrow}6$) 글리코시드결합의 galactan이 다당류 주성분으로 밝혀졌으며 galacturonic acid가 결합되어 있기 때문에 산성적 성질을 나타내고 있었다. 또한 M-LCC-A에서는 galacturonic acid 의 carboxyl 그룹이 리그닌의 ${\alpha}$-와 ${\gamma}$-위치에서 ester결합이 존재함이 확인되었다.

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Spectrophotometric Determination of Nizatidine and Ranitidine Through Charge Transfer Complex Formation

  • Walash, M.;Din, M.-Sharaf-EI;Metwalli, M.E.S.;RedaShabana, M.
    • Archives of Pharmacal Research
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    • v.27 no.7
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    • pp.720-726
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    • 2004
  • Two Spectrophotometric procedures are presented for the determination of two commonly used H2-receptor antagonists, nizatidine (I) and ranitidine hydrochloride (II). The methods are based mainly on charge transfer complexation reaction of these drugs with either ${\rho}-chloranilic$ acid (${\rho}-CA$) or 2, 3 dichloro-5, 6-dicyanoquinone (DDQ). The produced colored products are quantified spectrophotometrically at 515 and 467 nm in chloranilic acid and 000 methods, respectively. The molar ratios for the reaction products and the optimum assay conditions were studied. The methods determine the cited drugs in concentration ranges of 20-200 and $20-160\;\mu\textrm{g}/mL$ for nizatidine and ranges of 20-240 and $20-140\;\mu\textrm{g}/mL$ for ranitidine with chloranilic acid and DDQ methods, respectively. A more detailed investigation of the complexes formed was made with respect to their composition, association constant, molar absorptivity and free energy change. The proposed procedures were successfully utilized in the determination of the drugs in pharmaceutical preparations. The standard addition method was applied by adding nizatidine and ranitidine to the previously analyzed tablets or capsules. The recovery of each drug was calculated by comparing the concentration obtained from the spiked mixtures with those of the pure drug. The results of analysis of commercial tablets and the recovery study (standard addition method) of the cited drugs suggested that there is no interference from any excipients, which are present in tablets or capsules. Statistical comparison of the results was performed with regard to accuracy and precision using student's t-test and F-ratio at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision.

Dehydrogenation of 9,10-Dialkyl-9,10-dihydroanthracene with 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (2,3-디클로로-5,6-디시아노-1,4-벤조퀴논을 利用한 9,10-디알킬-9,10-디히드로안트라센 化合物의 수소이탈 반응)

  • Wu-Lang Kim;Moo-Jin Jun
    • Journal of the Korean Chemical Society
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    • v.19 no.6
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    • pp.443-448
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    • 1975
  • A series of 9,10-dialkyl-9,10-dihydroanthracene has been dehydrogenated by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in good yields. The yield decreased with the larger alkyl groups in this 9,10-dialkyl-9,10-DHA series(DHA=dihydroanthracene). It is conceivable that trans-9,10-diisopropyl-9,10-DHA was dehydrogenated more rapidly than the cis-isomer, and, bassed on this observation, a concerted mechanism was ruled out and an ionic mechanism is proposed.

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