• Title/Summary/Keyword: AM-to-AM

검색결과 3,543건 처리시간 0.029초

저표본화된 주성분의 AM-FM 신호들로부터 대수적 분리와 에너지 연산자를 사용한 복조기 설계 및 특성 (Digital Demodulator Design and Characteristics Using Algebraic Separation and Energy Operator from Undersampled Two-Component AM-FM Signals)

  • 손태호;이민호
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제48권5호
    • /
    • pp.643-649
    • /
    • 1999
  • In this paper, we proposed that i) noise-tolerant four kinds of AM(Amplitude Modulation)-FM(Frequency Modulation) demodulators are designed, ⅱ) we derived undersampling frequency through the product via energy operator of the monocomponent AM-FM signals separated form two-component AM-FM signals, and ⅲ) these four kinds of AM-FM demodulators detect respectively information signals of the IA(Instantaneous Amplitude) and IF(Instantaneous Frequency) by undersampling frequency to be different each other from the undersampled monocomponet AM-FM signals. Particularly, the proposed algorithm can control undersampling frequency by an integer factor. And these efficient AM-FM demodulators are well worked with the undersampled AM-FM signals.

  • PDF

높은 대역폭 효율과 정진폭 신호 전송을 위한 CACB-Q2AM 변조 (CACB-Q2AM Modulation for High Bandwidth Efficiency and Constant Amplitude Signal Transmission)

  • 홍대기;강성진
    • 인터넷정보학회논문지
    • /
    • 제9권1호
    • /
    • pp.21-32
    • /
    • 2008
  • 본 논문에서는 정진폭 신호 특성을 갖는 기존의 정진폭 부호화된 다중 부호 이진 직교 (CACB: Constant Amplitude Coded Multicode Biothogonal) 변조의 구조를 유지하면서 대역폭 효율을 증가시킴으로써 전송률을 높일 수 있는 방식을 제안한다. 높은 대역폭 효율을 얻기 위한 방식으로는 기존에 제안되었던 직교위상-직교위상 진폭변조 ($Q^2$AM: Quadrature-Quadrature Amplitude Modulation), 그리고 정진폭 직교위상직교위상 진폭변조 ($CA-Q^2$AM: Constant Amplitude-$Q^2$AM) 방식을 이용한다. 먼저 가장 간단한 결합 방식인 CACB-$Q^2$AM 방식을 제안한다. 이 방식은 대역폭 효율은 증가하지만 정진폭 특성을 얻을 수는 없기 때문에 정진폭 특성을 유지하기 위한 새로운 첫 번째 CACB-CA-$Q^2$AM (CACB-CA-$Q^2$AM I) 변조 방식을 제안한다. 그러나 이 방식은 정진폭을 얻기 위해 여분의 부호화 과정이 필요하므로 대역폭 효율이 낭비되는 단점이 있다. 마지막으로 대역폭 효율을 감소시키지 않는 새로운 두 번째 CACB-CA-$Q^2$AM (CACB-EA-$Q^2$AM II) 변조 방식을 제안한다. 컴퓨터모의실험을 통해 제안된 시스템의 성능을 평가함으로서 제안된 CACB-CA-$Q^2$AM II 변조 방식의 효율성을 보이도록 한다.

  • PDF

Effect of Vehicles and Enhancers on the in vitro Skin Penetration of Aspalatone and Its Enzymatic Degradation Across Rat Skins

  • Gwak, Hye-Sun;Chun, In-Koo
    • Archives of Pharmacal Research
    • /
    • 제24권6호
    • /
    • pp.572-577
    • /
    • 2001
  • The feasibility of skin penetration was studied for aspalatone (AM, acetylsalicylic acid maltol ester), a novel antithrombotic agent. In this studys hairless mouse dorsal skins were used as a model to select composition of vehicle and AM. Based on measurements of solubility and partition coefficient, the concentration of PC that showed the highest flux for AM across the hairless mouse skin was found to be 40%. The cumulative amount permeated at 48 h, however, appear inadequate, even when the PC concentration was employed. To identify a suitable absorption enhancer and its optimal concentration for AM, a number of absorption enhancers and a variety of concentration were screened for the increase in transdermal flux of AM. Amongst these, linoleic acid (LOA) at the concentration of 5% was found to have the largest enhancement factor (i.e., 132). However, a further increase in AM flux was not found in the fatty acid concentration greater than 5%, indicating the enhancement effect is in a bell-shaped currie. In a study of the effect of AM concentration on the permeation, there was no difference in the permeation rate between 0.5 and 1% for AM, below its saturated concentration. At the donor concentration of 2%, over the saturated condition, the flux of AM was markedly increased. A considerable degradation of AM was found during permeation studies, and the extent was correlated with protein concentrations in the epidermal and serosal extracts, and skin homogenates. In rat dorsal skins, the protein concentration decreased in the rank order of skin homogenate > serosal extract > epidermal extract. Estimated first order degradation rate constants were $6.15{\pm}0.14,{\;}0.57{\pm}0.02{\;}and{\;}0.011{\pm}{\;}0.004{\;}h^{-1}$ for skin homogenate, serosal extract and epidermal extract, respectively. Therefore, it appeared that AM was hydrolyzed to some extent into salicylmaltol by esterases in the dermal and subcutaneous tissues of skin. taken together, our data indicated that transdermal delivery of AM is feasible when the combination of PC and LOA is used as a vehicle. However, since AM is not metabolically stable, acceptable degradation inhibitors may be nervessary to fully realize the transdermal delivery of the drug.

  • PDF

Qualitative Mapping of Ambient Intelligence Characteristics to Operating System Features in Smart Environment

  • Choo, Young-Yeol
    • International Journal of Contents
    • /
    • 제2권4호
    • /
    • pp.1-7
    • /
    • 2006
  • The goal of Ambient Intelligence (AmI) is to build a smart environment for users where they are supported in some of their activities by many interaction mechanisms. The diversity of AmI characteristics requires special support from Operating Systems (OSes). In this paper, in order to support a conscious choice of an operating system for any specific AmI application, features requested by AmI systems were characterized and defined considering various applications. Then, characteristics of existing Operating Systems have been investigated in the context of AmI application support to relate their key characteristics to the typical requirements of AmI systems. Qualitative mapping table between AmI characteristics and as features has been proposed with an illustration of how to use it. As no as completely covers the range of characteristics required by AmI systems, challenging issues are summarized for the development of a new as and a product line of OSes.

  • PDF

일제시대 사암침법에 관한 의사학적 고찰 - 문헌중심으로 - (Medical Historical Studies on various parties of Sa-am acupuncture)

  • 정유옹;차웅석;김남일
    • 한국의사학회지
    • /
    • 제22권1호
    • /
    • pp.47-55
    • /
    • 2009
  • The Sa-am acupuncture is the acupuncture method created during Chosun Dynasty. It is a unique acupuncture method that was created solely in Korea. Its theories are based on the 69th article of "Classic of Difficult Issues", or Nanjing (難經), which says "tonify its mother when deficiency occurs, and purgate its son when excess occurs" (虛則補其母, 實則瀉其子); the concept of "controlling the viscera which restrains the target" "抑其官" was added to this theory to form the principle of Sa-am acupuncture. It is significant that it turns to the basic principles of the Five Viscera and Six Bowels rather than the 體針 or 阿是針 of the existing acupuncure. Sa-am acupuncture was established in the middle of Chosun Dynasty and was popularized to the practitioners of Korean Medicine through transcripts and printed books. The medical books of at the time of Japanese imperialism that introduced Sa-am acupuncture are "經絡學總論", "舍岩鍼灸訣", "經濟要訣", "靑囊訣", "察病要訣", "濟世寶鑑", "經驗寢具編", and "舍岩 靑囊訣". The magazine that mentions the Sa-am acupuncture is "韓方醫藥". The books on Traditional Medicine that is related to Sa-am acupuncture were of great help in reconstruction of Sa-am acupuncture after the liberation of Korea and explaining the principle of Sa-am acupunture in various angles.

  • PDF

네트워크 약리학을 통한 황기의 항비만 효능 및 작용기전 예측 연구 (Prediction of functional molecular machanism of Astragalus membranaceus on obesity via network pharmacology analysis)

  • 김미혜
    • 대한본초학회지
    • /
    • 제38권1호
    • /
    • pp.45-53
    • /
    • 2023
  • Objectives : Network pharmacology-based research is one of useful tool to predict the possible efficacy and molecular mechanisms of natural materials with multi compounds-multi targeting effects. In this study, we investigated the functional underlying mechanisms of Astragalus membranaceus Bunge (AM) on its anti-obesity effects using a network pharmacology analysis. Methods : The constituents of AM were collected from public databases and its target genes were gathered from PubChem database. The target genes of AM were compared with the gene set of obesity to find the correlation. Then, the network was constructed by Cytoscape 3.9.1. and functional enrichment analysis was conducted to predict the most relevant pathway of AM. Results : The result showed that AM network contained the 707 nodes and 6867 edges, and 525 intersecting genes were exhibited between AM and obesity gene set, indicating that high correlation with the effects of AM on obesity. Based on GO biological process and KEGG Pathway, 'Response to lipid', 'Cellular response to lipid', 'Lipid metabolic process', 'Regulation of chemokine production', 'Regulation of lipase activity', 'Chemokine signaling pathway', 'Regulation of lipolysis in adipocytes' and 'PPAR signaling pathway' were predicted as functional pathways of AM on obesity. Conclusions : AM showed high relevance with the lipid metabolism related with the chemokine production and lipolysis pathways. This study could be a basis that AM has promising effects on obesity via network pharmacology analysis.

변곡점 검출을 이용한 AM-FM 신호의 순간주파수 추정 (Instantaneous Frequency Estimation of AM-FM Signals using the Inflection Point Detection)

  • 임병관
    • 전기전자학회논문지
    • /
    • 제24권4호
    • /
    • pp.1081-1085
    • /
    • 2020
  • 변곡점 추출방법을 활용하여 AM-FM신호의 순간주파수를 추정하는 방법을 제안한다. 제안된 방법은 AM-FM신호의 국부적인 최대값/최소값을 변곡점 추출법을 활용하여 검출하며, 검출된 인접한 최대값/최소값 사이의 시간 간격을 계산하여 FM성분의 순간주파수를 추정한다. AM성분의 경우, 검출된 최소값/최대값의 포락선을 먼저 구하고 포락선의 최고값 간의 시간을 계산하여 순간주파수를 추정한다. 컴퓨터 모의실험으로 FM성분의 주파수가 고정된 경우와 변화하는 경우에 제안된 방법의 유용성을 검증한다. FM성분의 주파수가 일정한 AM-FM신호의 경우, 제안된 방법은 두 주파수 성분을 적절하게 추정한다. FM성분의 주파수가 변화하는 AM-FM신호의 경우, AM성분의 순간주파수는 적절히 추정되었으나 FM성분의 순간 주파수는 이론적인 주파수에서 편이되는 현상을 보인다. 이는 국소적인 최고점/최대점 검출로 표본수가 적어지는 효과에 따른 것으로, 저역통과 필터와 같은 후처리로 개선될 수 있다.

Antiviral Effect of Amphotericin B on Japanese Encephalitis Virus Replication

  • Kim, Hun;Kim, Seong-Jun;Park, Sue-Nie;Oh, Jong-Won
    • Journal of Microbiology and Biotechnology
    • /
    • 제14권1호
    • /
    • pp.121-127
    • /
    • 2004
  • Amphotericin B (AmB), an amphipathic polyene macrolide, is an antifungal drug produced by Streptomyces nodosus. Recently, AmB has been shown to exert antiviral activity against rubella virus and human immunodeficiency virus by different mechanisms. In this study, we evaluated the antiviral effect of AmB against Japanese encephalitis virus (JEV) and investigated which step of the viral life cycle was inhibited by AmB to understand the mechanism of antiviral action of AmB. AmB reduced both plaque size and number in the infected cells in a dose-dependent manner. In addition, a 200-fold reduction of infectious virus titer was observed by treatment of infected cells with $5\mug/ml$ of AmB. AmB acted at the post virus-infection step, but not during adsorption of virus to host cells. Western blot analysis revealed that the accumulated level of JEV envelope protein dramatically decreased in the infected cells by treatment with $5-10\mug/ml$ of AmB. Our results indicate that AmB inhibits the replication of JEV at the postinfection step by interfering with viral replication and/or by inhibiting the synthesis of viral proteins.

묵시 다원 AM-힙 (Implicit D-Ary AM-Heap)

  • 정해재
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
    • /
    • 제7권12호
    • /
    • pp.289-294
    • /
    • 2018
  • 본 논문에서는 AM-힙의 다원 버전인 AM(d)-힙이라고 하는 묵시 다원 우선순위 큐를 제안하며, 제안된 AM(d)-힙에서는 삽입에 O(1) 전이시간이 걸리고 삭제 연산에 O(logn) 시간이 걸린다. 실험 결과에 따르면, 전체적으로 d가 4 또는 8일 때 가장 우수한 성능을 나타내었다. 기존의 후위힙과 비교하면 AM(d)-힙이 약 1.5~1.8배 빠른 것으로 나타났다.

네트워크 약리학을 통한 당뇨병성 신병증에서의 황기와 산수유의 활성 성분 및 잠재 타겟 예측 (Network Pharmacology: Prediction of Astragalus Membranaceus' and Cornus Officinalis' Active Ingredients and Potential Targets to Diabetic Nephropathy)

  • 이근현;이하린;정한솔;신상우
    • 동의생리병리학회지
    • /
    • 제31권6호
    • /
    • pp.313-327
    • /
    • 2017
  • The purpose of this study is to predict the effects of macroscopic and integrative therapies by finding active ingredients, potential targets of Astragalus membranaceus (Am) and Cornus officinalis (Co) for diabetic nephropathy. We have constructed network pharmacology-based systematic and network methodology by system biology, chemical structure, chemogenomics. We found several active ingredients of Astragalus membranaceus (Am) and Cornus officinalis (Co) that were speculated to bind to specific receptors which had been known to have a role in the progression of diabetic nephropathy. Four components of Am and eleven components of Co could bind to iNOS; two ingredients of Am and six ingredients of Co could docking to cGB-PDE; one component of Am and nine components of Co could bind to ACE; three ingredients of Co with neprilysin; three components of Co with ET-1 receptor; four ingredients of Am and fourteen ingredients of Co with mineralocorticoid receptor; one component of Am and seven components of Co with interstitial collagenase; one ingredient of Am and ten ingredients of Co with membrane primary amine oxidase; one component of Am and four components of Co with JAK2; two ingredients of Am and one ingredient of Co with MAPK 12; one component of Am and five components of Co could docking to TGF-beta receptor type-1. From this work we could speculate that the possible mechanisms of Am and Co for diabetic nephropathy are anti-inflammatory, antioxidant and antihypertensive effects.