• Title/Summary/Keyword: Physical Form

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A Closed-Form BER Expression for Decode-and-Forward Cooperative Communication Protocol

  • Kong, Hyung-Yun
    • Journal of electromagnetic engineering and science
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    • v.9 no.2
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    • pp.66-70
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    • 2009
  • The decode-and-forward cooperative communication protocol allows single-antenna users in wireless environments to obtain the powerful benefits of multi-antenna systems without the need for physical arrays. Evaluating the performance of this protocol through simulations is time-consuming and therefore, a need exists for an analytical BER expression to serve as a reference. This paper proposed such an expression for coherently BPSK-modulated data.

The Preparation and Reactions of Some Fluorinated Cyclobutane Carboxylic Acids

  • J. D. Park;F. E. Rogers
    • Journal of the Korean Chemical Society
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    • v.16 no.3
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    • pp.178-188
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    • 1972
  • Diethyl itaconate was found to react tetrafluoroethylene, trifluorochloroethylene, and 1,1-difluoro-2,2-dichloroethylene quite rendily at $180^{\circ}C$ to form 1-carboxy-2,2,3,3,-tetrahalo-cyclobutane ethanoic acid derivatives ${C{\underline{X_2-CF_2-CH_2-}}C-(COOEt)-CH_2COOEt$, where X is Cl or F). Diethylcitraconate failed to yeild any cycloaddition products. The Physical and Chemical properties of the above esters and their dericatives are characterized and compared with other similar ring compounds.

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Exponential Lifetime Estimation with Unequal Interval Censoring (불균등 구간검사를 이용한 지수수명시간의 추정)

  • 이태섭;윤상운
    • Journal of Applied Reliability
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    • v.2 no.2
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    • pp.113-119
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    • 2002
  • The estimation of mean lifetimes in presence of interval censoring with replacement procedure are examined when the distributions of lifetimes are exponential. It is assumed that, due to physical restrictions and/or economic constraints, the number of failures is investigated only at several inspection times during the lifetime test. The maximum likelihood estimator is found in an implicit form. The Cramer-Rao lower bounds of the estimates are found in places of variances and by simulations the properties of the estimates are examined.

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Simulation of Moire Effect in 3D Displays

  • Saveljev, Vladimir;Kim, Sung-Kyu
    • Journal of the Optical Society of Korea
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    • v.14 no.4
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    • pp.310-315
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    • 2010
  • Theoretical and experimental investigations of moires in 3D displays were performed. To describe and minimize moires, we propose the polar representation form of moire waves. The experimental and theoretical data are in good agreement except in the neighborhood of the minimization angle. The implicit formulas are found for visible moires of line gratings at finite distances. The computer simulation and the physical experiments confirm the moire appearance for this case.

Electrical and Physical Evaluation of Processable Conductive PANI/PI Blends

  • Han, Moon-gyu;Im, Seung-soon
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.10a
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    • pp.219-222
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    • 1998
  • Polyaniline (PANI) has emerged as one of the most promising conducting polymers of the many types of conducting polymers in that it is soluble and therefore processable in the conducting form, and it is both environmentally and thermally stable together with high conductivity when it is doped by functionalized protonic acids like camphorsulfonic acid (CSA) and dodecylbenzenesulfonic acid (DBSA). (omitted)

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약물전달시스템 기술의 개발동향

  • 성하수;최연수
    • Fiber Technology and Industry
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    • v.8 no.2
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    • pp.183-191
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    • 2004
  • 의약품의 원재료인 약물은 사용 목적과 환자에 따라 정(tablet)이나 주사액과 같은 형태를 가지고 이를 제형(dosage form)이라 하고, 이런 형태의 물체를 제제(pharmaceutical preparations)라 한다. 신약이 대거 출현한 1950년대는 새로운 제형을 개발하는 물리약제학(physical pharmacy)이 활발히 연구되었다. 신약들은 당시의 기술로는 생체 내에서의 작용 등에 대한 명확한 자료와 근거 없이 약효가 있을 것으로 추정되었다. 그러나 분석기술과 기기의 발달로 약물의 체내 정량기술이 발달하면서 약물동태 학 (pharmacokinetics)이나 생물 약제학(biopharmaceutics)이 발달하여 약물의 체내 동태를 경시적으로 추적하는 일이 가능해졌다. (중략)

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Some Isoflavones from the Root of Caragana microphylla Lam (골담초의 이소후라본 성분)

  • Jin, Guang-Zhu;Li, Jing-Dao;Ahn, Byung-Zun
    • YAKHAK HOEJI
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    • v.36 no.5
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    • pp.481-485
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    • 1992
  • Five isoflavones were isolated from the root of Caragana microphylla Lam. and the structures have been identified by means of chemical and physical methods. The isoflavones are 7-hydroxy-4'-methoxyisoflavone(formononetin), $form ononetin-7-O-{\beta}-glucoside(ononin)$, 7-hydroxy-3', 4'-methylenedioxyisoflavone(pseudobaptigenin), $7-O-{\beta}-glucuopyranosyloxy-3'- hydroxy-4'-methoxyisoflavone(calycosin-7-O-{\beta}-gluc-oside)$ and maackiain.

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Microbial Metal Transformations

  • Gadd, Geoffrey M.
    • Journal of Microbiology
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    • v.39 no.2
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    • pp.83-88
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    • 2001
  • There is considerable interest in how microbiological processes can affect the behaviour of metal contaminants in natural and engineered environments and their potential for bioremediation. The extent to which microorganisms can affect metal contaminants is dependent on the identity and chemical form of the metal and the physical and chemical nature of the contaminated site or substance. In general terms, microbial processes which solubilize metals increase their bioavailability and potential toxicity, whereas those that immobilize them reduce bioavailability. The balance between mobilization and immobilization varies depending on the metal, the organisms, their environment and physico-chemical conditions.

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Study on Polymorphism of Cefotaxime Sodium, Cephradine, and Ceftriaxone Sodium

  • Park, Sun-Hee;Sohn, Young-Taek
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.228.2-229
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    • 2003
  • Investigation of polymorphism has become a requirement in the pharmaceutical industry because the physical properties and bioavailabilities of crystalline drugs depend on their polymorphic form. Two polymorphic modifications and one pseudopolymorphic modification of cefotaxime sodium were prepared by recrystallization in organic solvents under variable conditions. Four polymorphic modifications of cephardine were prepared by recrystallization. Three polymorphic modifications and one pseudopolymorphic modification of ceftriaxone sodium were prepared by recrystallization. (omitted)

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The Effect of Bank's Service Quality on Customer Satisfaction, Relationship Intention and Cross-Buying Intention (은행의 서비스품질이 고객만족과 관계지속의도 및 교차구매의도에 미치는 영향)

  • Joo, Young-Jae;Kwon, Hyeok Gi
    • Journal of Korea Society of Industrial Information Systems
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    • v.22 no.3
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    • pp.95-107
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    • 2017
  • This Study Categorized Service Quality of Banks into Interaction Quality, Physical Environment Quality, and Outcome Quality, and Proposed a Structural Model for Each Dimension of Service Quality on Customer Satisfaction, Persistence Intention and Cross-buying Intention, and Conducted an Empirical Analysis on the Customers who Use Banks. First, it was Confirmed that Three Dimensions of Service Quality Physical Environment Quality, Interaction Quality and Outcome Quality are One of the Sources that Form the Customer Satisfaction for Banks. Second, the Higher the Perceived Bank's Interactive Product Quality, Outcome Quality, and Physical Environment Quality Perceived by Customers Using Bank, it's Shown to have more Positive Effect on Customer Satisfaction, and the Effect Size was Shown in Order of Interaction Quality, Physical Environment Quality, and Outcome Quality. Third, Customer Satisfaction on Bank Services was Shown to have a Positive Effect on Relationship Intention and Cross-buying Intention. Finally, Based on the Results of this Analysis, the Implications of this Study and Future Research Directions were Presented.