• Title/Summary/Keyword: Associative mechanism

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A Study on the Real-time Optical Associative Memory Using Photorefractive Effects in $BaTiO_{3}$ ($BaTiO_{3}$ 의 광굴절 현상을 이용한 실시간 광연상 메모리에 관한 연구)

  • Ihm, J.T.;Oh, C.S.;Kim, S.I.;Park, H.K.
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.410-413
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    • 1988
  • In this paper, the real-time optical associative memory using multiple hologram which is generated with two angular multiplexed reference beams and Fourier transformed object beam in the $BaTiO_{3}$ crystal based on DFWM mechanism. When one image is recorded in the $BaTiO_{3}$ crystal, complete image can be recalled by 9 % partial input of the stored original image without any additional thresholding and optical feedback process. As an experimental result of multiple Fourier hologram which is recorded with two binary images, OHCHAS and PARKHK, we can obtain complete image recalled by 1/6 partial input of the stored image.

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Kinetic Study on the Alkaline Hydrolysis of the Substituted Phenyl N,N-diethyl-P-benzylphosphonamidates (치환 Phenyl N,N-diethyl-P-benzylphosphonamidates의 염기성 가수분해 반응에 대한 속도론적 연구)

  • Shon, Kyoung Hwa;Shin, Gap Cheol
    • Journal of the Korean Chemical Society
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    • v.43 no.1
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    • pp.85-91
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    • 1999
  • The second order rate constants for the hydrolysis of substituted phenyl N,N-diethyl-P-benzylphosphonamidates (2,4-$(NO_2)_2$, 4-$NO_2$, 4-CN, 4-Cl, 4-H)in 20% dioxane-water (v/v) have been determined by UV/Vis spectrophotometric method at various temperatures. The activation parameters (Ea, ${\Delta}H^{\neq}$,${\Delta}S^{\neq}$) were calculated from the rate constants and the reaction constant ($\rho$) was also estimated by Hammett equation. The activation entropies of the title reactions show considerably negative values, this result is not consistent with a dissociative mechanism (EA) in which a positive or a slightly negative value of the entropy of activation should be expected. Further, kinetic evidence for an associative mechanism (AE) was obtained from the linear free energy relationship. By the results of kinetic study for the alkaline hydrolysis of substituted phenyl N,N-diethyl-P-benzylphosphonamidates, it may be concluded that these reactions proceed through an associative mechanism.

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EXPERT KNOWLEDGE GATING MECHANISM IN THE HIERARCHICAL MODULAR SYSTEM

  • Shim, Jeong-Yon;Hong, You-Sik
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.288-291
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    • 2003
  • For the purpose of building the more efficient knowledge learning system, it is very important to make a good structure of the knowledge system first of all. The well designed knowledge system can make the stored knowledge to be easily accessed for knowledge acquisition and extraction. Expert knowledge can also play a good role for controlling. Accordingly, in this paper we propose the Hierarchical modular system with expert knowledge gating mechanism. This system consists of the mechanisms for knowledge acquisition, constructing the associative memory, knowledge inference and extraction according to the expert knowledge gating mechanism. We applied this system to the medical diagnostic area for classifying Virus(coxackie virus, echovirus, cold), Rhinitis(Nonallergic, allergic) and tested with symptom data

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Studies on the Quaternization of Tertiary Amines (Ⅳ). Kinetics and Mechanism for the Reaction of Substituted Phenacyl Tosylates with Substituted Pyridines

  • Lee, Oh-Seuk;Yoh, Soo-Dong
    • Bulletin of the Korean Chemical Society
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    • v.6 no.2
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    • pp.99-102
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    • 1985
  • Substituent effects of substrate and nucleophile for the reaction of substituted phenacyl tosylates with pyridines were determined conductometrically in acetonitrile. Activation parameters for these reactions were also calculated. The substituent effects in nucleophile were increased with electron-donating power of pyridines and Br${\o}$nsted linear relationship was shown. Rate constant was increased by both electron-donating and electron-attracting groups in the substrate. It seems that dissociative S$_{N}$2 ("loose" transition state) mechanism is operating in the case of electron-donating substituents while associative S$_{N}$2 ("tight" transition state) mechanism is operative in the case of electron-attracting substituents.

S$_N$2 Transition State Variation in the Benzenesulfonyl Chloride Sovolysis$^*$

  • Lee, Ik-Choon;Koo, In-Sun;Kang, Han-Keun
    • Bulletin of the Korean Chemical Society
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    • v.2 no.2
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    • pp.41-45
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    • 1981
  • For solvolyses of benzenesulfonylchlorides we determined transfer enthalpies of transition states, and solvent (TFE + EtOH) and substituent effects on rates. We have used the More O'Ferrall plots to show that transition states variation caused by solvent and substituent changes is consistent with an associative $S_N2$ mechanism for the nucleophilic substitution reaction of benzenesulfonylchlorides.

Solvolysis of Phenylacetyl Chlorides in Methanol-Acetonitrile Mixtures

  • Lee Ikchoon;Huh Chul;Lee Hai Whang
    • Bulletin of the Korean Chemical Society
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    • v.10 no.1
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    • pp.47-50
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    • 1989
  • The methanolysis reactions of phenylacetyl chlorides have been investigated in methanol-acetonitrile mixtures at temperatures ranging - $15.0-0.0^{\circ}C.$ Substituent and solvent effects on the rate supported an associative $S_N2$ mechanism for the solvolysis. Activation parameters indicated that the reaction is entropy controlled, while the a/s ratios of the Taft's solvactochromic correlation proved to be remarkably constant with a typical value of 0.50 that is consistent for the reactions proceeding by a typical $S_N2$ path.

A Collaborative Recommendation Method based on Fuzzy Associative Memory (퍼지연상기억장치에 기반한 협력 추천 방법)

  • 이동섭;고일주;김계영
    • Journal of KIISE:Software and Applications
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    • v.31 no.8
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    • pp.1054-1061
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    • 2004
  • At recent, people can easily access to information by Internet to be rapidly evolving. And also, the amount is rapidly increasing. So the techniques, to automatically extract the required information are very important to reduce the time and the effort for retrieving information. In this paper, we describe a collaborative filtering system for automatically recommending high-quality information to users with similar interests on arbitrarily narrow information domains. It asks a user to rate a gauge set of items. It then evaluates the user's rates and suggests a recommendation set of items. We interpret the process of evaluation as an inference mechanism that maps a gauge set to a recommendation set. We accomplish the mapping with FAM (Fuzzy Associative Memory). We implemented the suggested system in a Web server and tested its performance in the domain of retrieval of technical papers, especially in the field of information technologies. The experimental results show that it may provide reliable recommendations.

A Study on Fashion Design of Reproduced the Body by Power -Focusing on Visualization by Image Associative Action- (권력으로 재생산된 몸과 패션디자인 표현 연구 -이미지 연상기법에 의한 시각화를 중심으로-)

  • Kim, Minji
    • Journal of Fashion Business
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    • v.22 no.2
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    • pp.61-73
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    • 2018
  • Power is the driving force of society, and the generation of power is inevitable. as long as society is rganized hierarchically. According to Michael Foucault's discourse modern power operates as a mechanism of 'panopticon', a system that monitors the 'body' of man through discipline. Moreover. fashion as acts as a symbol of beauty that continues to co-exist with power for the purpose of exposing status and authority, and for displaying the trends within a culture. So, it is necessary to study fashion design according to the changing power structure that exists in society. The aim of this study is to suggest types of creative fashion design process by visualizing the Foucault's power discourse through the image associative action. The four types of creative fashion design that have been drawn by visualizing Foucault's power discourse are as follow: disciplinary power, imprisonment power and knowledge power. The first type of fashion design method is to emphasize the shoulder by using shoulder pads, strings, tabs, and incisions in the clothing. The second method is to expose the body by using see-through material and manipulating its composition to expose the body. Third method is to borrowing elements of underwear. Fourth method is to utilize patterns that represent power, such as weapons, bones, blood, muscles, skulls, and various human imagesin the clothing. Through this study we expect to utilize creative fashion design to visualize concepts of the humanities, such as philosophical discourse.

An Analog Content Addressable Memory implemented with a Winner-Take-All Strategy (승자전취 메커니즘 방식의 아날로그 연상메모리)

  • Chai, Yong-Yoong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.1
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    • pp.105-111
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    • 2013
  • We have developed an analog associative memory implemented with an analog array which has linear writing and erasing characteristics. The associative memory adopts a winner-take-all strategy. The operation for reading in the memory is executed with an absolute differencing circuit and a winner-take-all (WTA) circuit suitable for a nearest-match function of a content-addressable memory. We also present a system architecture that enables highly-paralleled fast writing and quick readout as well as high integration density. A multiple memory cell configuration is also presented for achieving higher integration density, quick readout, and fast writing. The system technology presented here is ideal for a real time recognition system. We simulate the function of the mechanism by menas of Hspice with $1.2{\mu}$ double poly CMOS parameters of MOSIS fabrication process.

Solvolysis of Benzoyl Cyanide (시안화 벤조일의 가용매분해반응)

  • Jeong Wha Kim;Ikchoon Lee;Se Chul Sohn;Tae Sup Uhm
    • Journal of the Korean Chemical Society
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    • v.27 no.2
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    • pp.95-101
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    • 1983
  • The pseudo-first order rate constants have been obtained for the solvolysis of benzoyl cyanide in various aqueous solvent mixtures and ethanol-trifluoroethanol mixtures at 1, 5, 10, 15 and $20^{\circ}C$. Values of n in the Kivinen polt, m values of Grunwald-Winstein polt, $\beta$ values of Leffler relationship and values of m and l in the extended Grunwald-Winstein polt have been calculated and studied the transition state variation caused by solvent changes using the More O'Ferrall polt and quantum mechanical approach. It has been shown that the reaction proceed via the associative $S_N2$ mechanism, using the transition state parameters and quantum mechanical model approach.

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