• Title, Summary, Keyword: EC-Mechanism

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Applying A Matrix-Based Inference Algorithm to Electronic Commerce

  • Lee, Kun-Chang;Cho, Hyung-Rae
    • Proceedings of the Korea Database Society Conference
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    • pp.353-359
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    • 1999
  • We present a matrix-based inference algorithm suitable for electronic commerce applications. For this purpose, an Extended AND-OR Graph (EAOG) was developed with the intention that fast inference process is enabled within the electronic commerce situations. The proposed EAOG inference mechanism has the following three characteristics. 1. Real-time inference: The EAOG inference mechanism is suitable for the real-time inference because its computational mechanism is based on matrix computation. 2. Matrix operation: All the subjective knowledge is delineated in a matrix form. so that inference process can proceed based on the matrix operation which is computationally efficient. 3. Bi-directional inference: Traditional inference method of expert systems is based on either forward chaining or backward chaining which is mutually exclusive in terms of logical process and computational efficiency. However, the proposed EAOG inference mechanism is generically bi-directional without loss of both speed and efficiency. We have proved the validity of our approach with several propositions and an illustrative EC example.

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Applying A Matrix-Based Inference Algorithm to Electronic Commerce

  • Lee, kun-Chang;Cho, Hyung-Rae
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • pp.353-359
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    • 1999
  • We present a matrix-based inference alorithm suitable for electronic commerce applications. For this purpose, an Extended AND-OR Graph (EAOG) was developed with the intention that fast inference process is enabled within the electronic commerce situations. The proposed EAOG inference mechanism has the following three characteristics. 1. Real-time inference: The EAOG inference mechanism is suitable for the real-time inference because its computational mechanism is based on matric computation.2. Matrix operation: All the subjective knowledge is delineated in a matrix form, so that inference process can proceed based on the matrix operation which is computationally efficient.3. Bi-directional inference: Traditional inference method of expert systems is based on either forward chaining or backward chaining which is mutually exclusive in terms of logical process and exclusive in terms of logical process and computational efficiency. However, the proposed EAOG inference mechanism is generically bi-directional without loss of both speed and efficiency. We have proved the validity of our approach with several propositions and an illustrative EC example.

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Photophysical and Electrochmical Studies of N,N-Bis (2,5-di-tert-butylphenyl) - 3,4,9,10 perylenebis (dicarboximide) (DBPI)

  • El-Hallag, Ibrahim S.;El-Daly, Samy A.
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.989-998
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    • 2010
  • The titled dye of DBPI gives amplified spontaneous emission (ASE) with maximum at 580 nm upon pumping by nitrogen laser (${\lambda}_{ex}\;=\;337.1\;nm$). The ground state absorption cross section (${\sigma}_A$) and emission cross section (${\sigma}_E$) as well as effective emission cross section(${\sigma}^*_E$) have been determined. The electronic absorption spectra of DBPI were measured in ethanol and tetrahydrofuran at room and low temperature. DBPI displays molecular aggregation in water. The photochemical reactivity of DBPI was also studied in carbon tetrachloride upon irradiation with 525 nm light. The electrochemical investigation of DBPI dye has been carried out using cyclic voltammetry and convolution deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in two different solvents acetonitrile ($CH_3CN$) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive direction, the compound was oxidized by loss of two sequential electrons, which were followed by a fast dimerization and/or aggregation process i.e $EC_{dim1}EC_{dim2}$ mechanism. The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.

Cys-92, Cys-95, and the C-Terminal 12 Residues of the Vibrio harveyi Ferric Uptake Regulator (Fur) are Functionally Inessential

  • Sun, Kun;Cheng, Shuang;Zhang, Min;Wang, Fang;Sun, Li
    • Journal of Microbiology
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    • v.46 no.6
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    • pp.670-680
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    • 2008
  • Ferric uptake regulator (Fur) is a global regulator involved in multiple aspects of bacterial life. The gene encoding the Vibrio harveyi Fur ($Fur_{Vh}$) was cloned from a pathogenic V. harveyi strain isolated from diseased fish. $Fur_{Vh}$ shares 77% overall sequence identity with the Escherichia coli Fur ($Fur_{Ec}$) and could complement a mutant of $Fur_{Ec}$. Like $Fur_{Ec}$, $Fur_{Vh}$ possesses two cysteine residues at positions 92 and 95, yet unlike $Fur_{Ec}$, in which these cysteine residues constitute part of the metal ion coordination site and hence are vital to the repressor activity, C92 and C95 of $Fur_{Vh}$ proved to be functionally inessential. Further study identified a Vibrio Fur signature sequence, which is preserved in all the ten Vibrio Fur proteins that have been discovered to date but in none of the non-vibrio Fur proteins. Site-directed and random mutation analyses of the signature residues, the cysteine residues, and seven highly charged amino acid residues indicated that D9, H32, C137, and K138 of $Fur_{Vh}$ are functionally important but D9, C137, and K138 can be replaced by more than one functional substitutes. Systematic deletion analysis demonstrated that the C-terminal 12 residues of $Fur_{Vh}$ are functionally inessential. These results (i) indicated that the activation mechanism, or certain aspects of which, of $Fur_{Vh}$ is possibly different from that of $Fur_{Ec}$; and (ii) suggested that it is not very likely that the C-terminal 12 residues play any significant role in the activation or stability of $Fur_{Vh}$; and (iii) provided insights into the potential function of the local structure involving C137 and K138.

Control of X Chromosome Reactivation and Determination of the Ratio of Sex Chromosome to Autosome in Embryonal Carcinoma Cell-Somatic Cell Hybrids (배종양 세포와 체세포 간의 융합 세포에서 X 염색체 재활성화의 조절과 성염색체에 대한 상염색체 비율의 결정)

  • 이광호
    • The Korean Journal of Zoology
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    • v.39 no.1
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    • pp.75-88
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    • 1996
  • OTF9-63 (OTF9) and P19S1O1A1 (P19) embryonal carcinoma (EC) cells were examined for their ability to produce the readivation of inactive X chromosomes from somatic cells. They were hybridized with various somatic cells and resulting HATr EC-somatic cell clones were analysed for their morphology, chromosomal replication pafterns and expression proffies of X-linked and distantiy located genes, Hprt and Pgk-1. The results demonstrated that 0RF9 cells could reactivate the inactive X chromosome whereas P19 cells could not. In adition, EC-somatic cell hybrids tended to reduce the number of sex chromosomes in long-term culture, resulting m 1:2 ratio of sex chromosomes to autosomes The use of EC cell hybrids provides an experimental system for studying the mechanism(s) of the X-reactivatio that is initiated and maintained from meiotic prophase of oogenesis to early embryogenesis.

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Effect of Tea Polyphenols on the Adhesion of Highly Metastatic Human Lung Carcinoma Cell Lines to Endothelial Cells in Vitro

  • Zheng, Feng-Jin;Shi, Lin;Yang, Jun;Deng, Xiao-Hui;Wu, Yu-Quan;Yan, Xi-Qing;Huang, Ning
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.3751-3755
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    • 2012
  • Aim: Tea polyphenols are known to play roles in critical steps of human lung carcinoma cell metastasis. For understanding the mechanisms whereby they inhibit tumor metastasis, the present study was conducted to investigate their effects on the adhesion of highly metastatic lung carcinoma cell lines (PG cells) to endothelial cells (EC cells) and adhesion molecule expression in vitro. Methods: The expression of CD44 or CD54 in the PG cells was detected by flow cytometry and adhesion of PG cells to EC cells was assessed by confocal microscopy double fluorescence staining. Results: The results showed that tea polyphenols: (1) inhibited the expression of CD44 and CD54, two important adhesion molecules in the PG cells in a dose-dependent manner; (2) significantly blocked the adhesion of PG cells to EC cells not only in a state of rest but also when active; and (3) influenced CD44 and CD54 expression during the adhesion process of PG cells to EC cells. Conclusions: The data indicated that the blocking role of tea polyphenols in the adhesion of PG cells to EC cells is related to CD44 and CD54. The mechanism of tea polyphenol prevention of human lung carcinoma metastasis might be through inhibiting adhesion molecule expression to block cancer cell adhesion.

Classification of Snowfalls over the Korean Peninsula Based on Developing Mechanism (발생기구에 근거한 한반도 강설의 유형 분류)

  • Cheong, Seong-Hoon;Byun, Kun-Young;Lee, Tae-Young
    • Atmosphere
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    • v.16 no.1
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    • pp.33-48
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    • 2006
  • A classification of snowfall type based on development mechanism is proposed using previous snowfall studies, operational experiences, etc. Five types are proposed: snowfall caused by 1) airmass transformation (AT type), 2) terrain effects in a situation of expanding Siberian High (TE type), 3) precipitation systems associated with extratropical cyclones (EC type), 4) indirect effects of extratropical cyclones passing over the sea to the south of the Korean peninsula (ECS type), and 5) combined effects of TE and ECS types (COM type). Snowfall events during 1981-2001 are classified according to the 5 types mentioned above. For this, 118 events, with at least one station with daily snowfall depth greater than 20 cm, are selected. For the classification, synoptic weather charts, satellite images, and precipitation data are used. For TE and COM types, local sea-level pressure chart is also used to confirm the presence of condition for TE type (this is done for events in 1990 and thereafter). The classification shows that 109 out of 118 events can be classified as one of the 5 types. In the remaining 8 events, heavy snowfall occurred only in Ullung Island. Its occurrence may be due to one or more of the following mechanism: airmass transformation, mesoscale cyclones and/or mesoscale convergence over the East Sea, etc. Each type shows different characteristics in location of snowfall and composition of precipitation (i.e., dry snow, rain, and mixed precipitation). The AT-type snowfall occurs mostly in the west coast, Jeju and Ullung Islands whereas the TE-type snowfall occurs in the East coast especially over the Young Dong area. The ECS-type snowfall occurs mostly over the southern part of the peninsula and some east cost area (sometimes, whole south Korea depending on the location of cyclones). The EC- and COM-type snowfalls occur in wider area, often whole south Korea. Precipitation composition also varies with the type. The AT-type has a snow ratio (SR) higher than the mean value. The TE- and EC-type have SR similar to the mean. The ECS- and COM-type have SR values smaller than the mean. Generally the SR values at high latitude and mountainous areas are higher than those at the other areas. The SR value informs the characteristics of the precipitation composition. An SR value larger than 10 means that all precipitation is composed of snow whereas a zero SR value means that all precipitation is composed of rain.

SGML/XML 기반 문서 정보 시스템

  • 주종철;김현기;박영찬
    • Proceedings of the CALSEC Conference
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    • pp.69-78
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    • 1998
  • SGML/XML 기반 문서 정보 시스템의 문서 포맷은 인간이 비교적 쉽게 이해할 수 있으며 기존의 문서 정보 시스템에서는 접근 불가한 레벨까지 인간이 접근할 수 있는 통로를 제공한다. 또한, 문서처리 관점에서 보면 기존의 각 CAL/EC관련 응용 프로그램에서 생성된 데이터는 문서 또는 파일 단위의 접근으로 업무레벨에 도움을 주는 것이 제한적인 것에 반해 SGML/XML 기반 문서정보 시스템은 DTD(Document Type Definition)에서 설계된 엘리먼트, 속성, 엔티티 등의 단위까지 접근할 수 있는 Mechanism으로 기존의 문서 정보 시스템과 차별화 되는 지식 매체로서 지식기반 시스템의 하부 프레임워크를 제공한다. SGML/XML 기반 문서 정보 시스템의 요소로서 SGML/XML 문서 정보 검색 시스템은 표현된 계층적 논리정보를 이용하여 다양한 문서 접근점을 제공할 수 있으며, 사용자 요구에 적합한 문서의 재사용 및 동적인 문서제시를 가능하게 한다. 또한, SGML/XML 문서 정보 관리 시스템은 공동 저작을 위한 세부 논리적 단위별 check-in/check-out, 액세스 제어, 버전닝 기능 등을 제공하여 기업 내 자산 관리를 위한 새로운 파라다임을 제공한다. 본 논문에서는 구현 사례와 더불어 SGML/XML 기술이 CALS/EC 추진에 주는 영향과 향후 바람직한 CALS/EC 또는 가상기업(Virtual Enterprise)구축을 위한 기술적 방향에 대해 논한다.

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Design and Implementation of Distributed Mutual Exclusion Lock Counter Algorithm (분산 상호 배제 카운트 알고리즘을 이용한 클라이언트 사용자 구분 시스템 개발)

  • Jang, Seung-Ju
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.4
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    • pp.1227-1235
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    • 2000
  • In this paper, we propose new concepts that the distributed counter value with the distributed EC system identify each user who users the distributed system. The web user should register his/her own user ID in the cyber shopping mall system. Instead of registration, this paper proposes the proprietary mechanism that is distributing counter. The counter assigns the distinguished number to each client. The distributed lock algorithm is used for mutual assignment of the counter to each client. The proposed algorithm is the best solution in the distributed environment system such as cyber shopping mall. If a user should register his/her own ID in every EC system, he/she may not try to use these uncomfortable systems. The mutual counter is used to identify each client. All of these features are designed and implemented on Windows NT web server. Also these features were experiments with 5 clients for 300 times. According to the experiments, clients have their own mutual counter value. The proposed algorithm will be more efficient in internet application environment. Moreover, it will improve the number of internet users.

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On the Electrochemical Reduction of O, O-Dimethyl-O-(3-Methyl-4-Nitrophenyl)-Phosphorthioate (Fenitrothion) Pesticide in Acetonitrile Solution (Acetonitrile 용액중에서 살충제 O, O-Dimethyl-O-(3-Methyl-4-Nitrophenyl)-Phosphorothioate (Fenitrothion)의 전기화학적 환원)

  • Il-Kwang Kim;Youn-Geun Kim;Hyun-Ja Chun
    • Journal of the Korean Chemical Society
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    • v.32 no.3
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    • pp.186-194
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    • 1988
  • The electrochemical reduction of O,O-dimethyl-O-(3-methyl-4-nitrophenyl)-phosphorothioate (Fenitrothion) has been studied in acetonitrile solution containing surfactant micelle by direct current (DC)-differential pulse (DP) polarography, cyclic voltammetry (CV) and controlled potential coulometry (CPC). The partially reversible electron transfer-chemical reaction(EC, EC mechanism) of fenitrothion reduction proceeded by four electron transfer to form O,O-dimethyl-O-(3-methyl-4-hydroxyaminophenyl)-phosphorothioate which undergoes single bond of the phosphorus atom and phenoxy group cleaves to give p-amino-m-cresol and dimethyl thiophosphinic acid as major product by two electron transfer-protonation at higher negative potential. The polarograpic reduction waves shown to suppressed due to inhibitory effect of sodium lauryl sulfate micelle solution and split up on selectivity of anionic micelle effect in two step at the first reduction peak.

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