• 제목/요약/키워드: pattern transfer

검색결과 794건 처리시간 0.031초

Information Retrieval: A Communication Process in the 21st Century Library

  • Umeozor, Susan Nnadozie
    • International Journal of Knowledge Content Development & Technology
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    • 제10권2호
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    • pp.7-18
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    • 2020
  • Communication is a process involving a group of interrelated elements working together for the purpose of information transfer. This paper discusses information retrieval as a communication process in the 21st century library. The difficulties associated with access to recorded knowledge through bibliographic control devices have been exacerbated by the interposition of additional encoding processes in the library and further decoding by the users. In addition, the innovation of internet/web has revolutionized the means and mode of communication process in the library by flooding information seekers with information and creating an illusion of self-sufficiency in many users. With these changes in information seeking behaviour and pattern, a cybernetic approach to information retrieval has emerged emphasizing adaptive control mechanisms and feedback processes. This paper argues that libraries should strive to continuously remain relevant by keeping abreast with changes in the behavior of information users. To this end, this paper proposes apomediatic-cybernetic model of communication, which illustrates information retrieval processes for the 21st-century library.

암모니아/물 흡수식 냉동기의 판형 재생기의 수치해석 (Numerical Analysis of a Plate Type Generator for Ammonia/Water Absorption Refrigerators)

  • 지제환;정은수;정시영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.304-310
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    • 2001
  • A numerical model which simulates the heat and mass transfer processes within a counter-current plate type generator for ammonia/water absorption refrigerators was developed. Ammonia/water solution flows downward under gravity and ammonia/water vapor generated by flow boiling flows upward. The flow pattern within the generator was assumed to be a bubbly flow, and the liquid and vapor phase were assumed to be saturated. It was shown that the boiling of ammonia occurred mainly in the upper part of the generator. The effects of the generator length, the wall temperature and the mass flow rate of ammonia/water solution into the generator on the generation of ammonia/water vapor were investigated.

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양 끝이 개방된 경사진 채널 내에서의 혼합대류에 관한 수치적 연구 (A Numerical Study on the Mixed Convection in Open-Ended Inclined Channels)

  • 박일용;배대석
    • Journal of Advanced Marine Engineering and Technology
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    • 제29권1호
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    • pp.78-85
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    • 2005
  • A numerical calculation is performed to study the effects of buoyancy force on the heat transfer characteristics of laminar forced convection flow in inclined parallel plates with the upper part cooled and the lower Part heated uniformly. Numerical results are presented for the Reynolds number ranges from $4.0\times10^{-3}$ to $1.13\times10^{-1}$. the angle of inclination, $\theta$. from 0 to 90 degree and Pr of the high viscosity fluid is 909. It is found that the flow pattern of mixed convection in inclined parallel Plates can be classified into four patterns which affected by Reynolds number and the angle of inclination.

Structure and Function of the Developmental Signaling Molecule Hedgehog

  • Leahy, Daniel J.
    • BMB Reports
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    • 제32권2호
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    • pp.103-111
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    • 1999
  • Hh proteins represent a new signaling paradigm in metazoan development. In species ranging from fruit flies to humans, Hh proteins mediate multiple processes vital to appropriate pattern formation in the developing embryo. Hh proteins undergo an autoprocessing event in which the full-length protein is cleaved into N-terminal and C-terminal domains (Hh-N and Hh-C, respectively), and a cholesterol moiety becomes covalently attached to Hh-N. All known signaling activities of Hh proteins are mediated by Hh-N while both the cleavage and cholesterol transfer reactions are mediated by Hh-C. The cholesterol attached to Hh-N is required to retrict the range of Hh signaling and may be involved in ensuring appropriate reception of the Hh signal in target tissues. Disruptions of Hh signaling pathways lead to severe developmental defects in newborns and cancers in adults. While studies of Hh proteins have yielded a wealth of new insight into the molecular mechanisms of metazoan development, many outstanding questions concerning Hh signaling mechanisms ensure that unraveling the secrets of this molecule will keep scientists well entertained for the foreseeable future.

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나노임프린트 리소그래피에서의 폴리머 레지스트의 변형에 관한 분자 동역학 시뮬레이션 (Molecular Dynamics Simulation of Deformation of Polymer Resist in Nanoimpirnt Lithography)

  • 강지훈;김광섭;김경웅
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.410-415
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    • 2004
  • Molecular dynamics simulations of nanoimprint lithography in which a stamp with patterns is pressed onto amorphous poly-(methylmethacrylate) (PMMA) surface are performed to study the deformation of polymer. Force fields including bond, angle, torsion, inversion, van der Waals and electrostatic potential are used to describe the intermolecular and intramolecular force of PMMA molecules and stamp. Periodic boundary condition is used in horizontal direction and $Nos\acute{e}$-Hoover thermostat is used to control the system temperature. As the simulation results, the adhesion forces between stamp and polymer are calculated and the mechanism of deformation are investigated. The effects of the adhesion force and friction force on the polymer deformation are also studied to analyze the pattern transfer in nanoimprint lithography. The mechanism of polymer deformation is investigated by means of inspecting the indentation process, molecular configurational properties, and molecular configurational energies.

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UV임프린트 공정에서 임프린팅 가압력 및 가압시간에 따른 레진 잔막 두께형성에 대한 실험연구 (Study on the Formation of Residual Layer Thickness by Changing Magnitude and Period of UV Imprinting Pressure)

  • 신동혁;장시열
    • Tribology and Lubricants
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    • 제26권5호
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    • pp.297-302
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    • 2010
  • This study is focused on the resin layer formation of UV imprinting process by changing imprinting pressure and period. The mold shape is made for the process of window open over the pattern transfer area and the imprinting period is assigned as the time just before the UV light curing. The residual layer is measured by changing the imprinting period and pressure magnitude, and the measured data of residual layer provides useful information for the design of the process conditions of imprinting processes.

근거리 무선전력전송용 헬리컬 코일과 스파이럴 코일에 대한 고찰 (Review for the Helical coil type and Spiral coil type in a mid range Wireless Power Transfer System)

  • 박재현;양해열;김창선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.11-12
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    • 2011
  • In electromagnetic coupled resonance(ECR) WPT system, the main key for wireless power transmission is the design method of the ECR coils. The ECR coils is classified to the helical coil(3D) type and the spiral coil(2D) type as a coil structure. The pattern of the spiral coil type has been studied in favor of commercialization. In this paper, the design characteristics of the helical coil and the spiral coil is considered using a Vector Network Analyzer. It is analyzed according to the distance of coupling coefficient between the ECR coils. Also, It is analyzed for the relationships such as the maximum transmission efficiency and the resonant frequency depending on the distance between the coils.

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반도체 소자의 정전기 완화특성 (Characteristics of Electrostatic Attenuation in Semiconductor)

  • 김두현;김상렬
    • 한국안전학회지
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    • 제14권3호
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    • pp.69-77
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    • 1999
  • As the use of automatic handling equipment for sensitive semiconductor devices is rapidly increased, manufacturers of electronic components and equipment need to be more alert to the problem of electrostatic discharges(ESD). Semiconductor devices such as IC, LSI, VLSI become a high density pattern of being more fragile by ESD phenomena. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the electrostatic discharge sensitive devices. Accordingly, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated to evaluate the ESD phenomina in the semiconductors in this paper. The required data are obtained by Static Honestmeter. Also The results in this paper can be used for the prevention of semiconductor failure by ESD.

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Algorithm for Generating Traffic Distributions in ATM Networks using 2-D LHCA

  • Cho, Sung-Jin;Kim, Seok-Tae;Kim, Jae-Gyeom;Kim, Han-Doo;Park, Un-Sook
    • 한국멀티미디어학회논문지
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    • 제2권2호
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    • pp.176-183
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    • 1999
  • Using Asynchronous Transfer Mode(ATM) which is a high-bandwidth, low-delay, cell switching and multiplexing technology, Broadband-Integrated Services Digital Network (B-ISDN) can support communication services of all kinds. To evaluate the performance of ATM networks, traffic source models to meet the requirements are demanded. We can obtain random traffic distribution for ATM networks by using the Cellular Automata (CA) which have effective random pattern generation capability. In this paper we propose an algorithm using 2-D LHCA to generate more effective random patterns with good random characteristics. And we show that the randomness by 2-D LHCA is better than that of the randomness by 1-D LHCA.

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단자망을 이용한 직류전기철도 해석방안에 관한 연구 (A Study on Analysis Method of DC Electric Railroad using Terminal Network Analysis)

  • 이장무;장동욱;김재원;한문섭;정환수;김주락
    • 전기학회논문지
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    • 제65권11호
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    • pp.1913-1918
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    • 2016
  • In order to analyze the power consumption pattern of the DC urban rail system, the method to obtain a solution establishing the current equation according to fixed position of the substation and varying position of the train is used. The proposed analysis method using the network analysis is to model the transfer function of the component constituting a direct current power supply system (dc substation, train, catenary) to the voltage and current. By multiplying the model formula consecutive, it can calculate the voltage and current of each element of power supply circuit and shows a simple case analysis.