• Title/Summary/Keyword: digital reference

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A Low-Noise and Small-Size DC Reference Circuit for High Speed CMOS A/D Converters

  • Hwang, Sang-Hoon;Song, Min-Kyu
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.7 no.1
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    • pp.43-50
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    • 2007
  • In a high-speed flash style or a pipelining style analog-to-digital converter (A/D converter), the DC reference fluctuation caused by external noises becomes serious, as the sampling frequency is increased. To reduce the fluctuations in conventional A/D converters, capacitors have been simply used, but the layout area was large. Instead of capacitors, a low-noise and small-size DC reference circuit based on transmission gate (TG) is proposed in this paper. In order to verify the proposed technique, we designed and manufactured a 6-bit 2GSPS CMOS A/D converter. The A/D converter is designed with a 0.18um 1-poly 6-metal n-well CMOS technology, and it consumes 145mW at 1.8V power supply. It occupies the chip area of 977um by 1040um. The measured result shows that SNDR is 36.25 dB and INL/DNL is within 0.5LSB, even though the DC reference fluctuation is serious.

Content Analysis of Collaborative Digital Reference Service Knowledge Information Database (협력형 디지털 참고서비스(CDRS) 지식정보DB 내용분석 연구)

  • Jang, Su Hyun;Nam, Young Joon
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.32 no.2
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    • pp.101-123
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    • 2021
  • This study analyses the questions and answers contained in the Knowledge Information Database of the collaborative digital reference service, 'Ask a librarian'. And based on the results of status of user requests, this study draws information usage behavior in the early stages of the service was derived. 1,124 Knowledge Information Database items out of 3,506 cases was analyzed by nine criterion. ① Number of questions and whether to be reference questions, ② Subject and keywords of the question, ③ Purpose of the question, ④ Type of question, ⑤ User's information request, ⑥ Information source and reference services provided by the librarian, ⑦ Number of days to answer, ⑧ Level of the participating library, ⑨ Question type by topic. As a results of analysis, first, users asked for reference questions from various topics as needed, rather than one from a similar topic at a time, but more than half of the total pure reference questions were from the field of library information science. Second, about 71.35% of users were using the 'Ask a librarian' service to recommend a list of information resources related to a particular topic or research problem, and there were also questions that required consultation on the reading situation. Third, the most preferred sources of information for users were bibliography, and in the case of online information sources, users did not relatively prefer them. Fourth, the number of days required to answer was able to confirm significant differences depending on the type of question and the level of the participating library. Fifth, 31.33% of the purpose of the general field question showed that were self-generated.

A Case Study on Morten Lasskogen's Cloud Series - Based on 3ds Max and Unreal Engine Technology -

  • JinXuan Zhao;Xinyi Shan;Jeanhun Chung
    • International journal of advanced smart convergence
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    • v.12 no.2
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    • pp.96-101
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    • 2023
  • Digital art creation has become an indispensable part of today's society, but traditional digital art production methods have been difficult to meet the growing creative needs of artists. Therefore, this study takes the cloud series works of artist Morten Lasskogen as an example and explores the application value of 3D Max and Unreal Engine in digital art created by analyzing the lighting effects in the works of art. This research aims to form reference materials through actual case analysis and provide artists with more efficient ideas for digital art creation.

A 1-8V 8-bit 300MSPS CMOS Analog to Digital Converter with high input frequence (네트워크 인터페이스를 위한 1-8V 8-bit 300MSPS 고속 CMOS ADC)

  • 주상훈;송민규
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.197-200
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    • 2002
  • In this paper, presents a 1.8V 8-bit 300MSPS CMOS Subranging Analog to Digital Converter (ADC) with a novel reference multiplex is described. The proposed hか converter is composed of Sub A/D Converter block, MUX (Multiplexer) block and digital block. In order to obtain a high-speed operation, further, a novel dynamic latch, an encoder of novel algorithm and a MUX block are proposed. As a result, this A/D Converter is operated 100MHz input frequence by 300MHz sampling rate.

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A Study on the Development of Reference Linking System Based on Digital Object Identifier for Korean Journal Articles (국내 학술지 논문의 DOI 기반 연계시스템 구축에 관한 연구)

  • 한혜영;정동열
    • Journal of the Korean Society for information Management
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    • v.17 no.4
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    • pp.207-227
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    • 2000
  • Recenily, major internalional STM(Science, Trchnical, and Mcdivine) Publichers have been developing prototype systems that can provide the refeence linking of jouinal articles within the scholarly literature on a cross-publisher basis using the URN(Universal Resouree Name). In Korea, it is hard to find the efforts to link the scattered digitalized documents to an individual user through a unified web. In this study, a linking model for an inergrated gatewny fro, bibliographic information to full tcxt has been desugned and 'Electronic Research Resourced Linking system (E3R/LS)' has been developed as a prototype for centralized static reference linking system. There are three major components for constructing refrernce linking systems. The firsl componcnt the Digital Object Identifiet(DO1). is introduced as the public identifier inrended to be applied wherever thr item needs to be identified. For denl~iymg Korean journal articles, llie extended SICI(Serlal Ilem and Conlribut~on Idealifier) has becn newly dehed in 1111s study and is used as a suiiia on DOI. The reierence datubasc conlams the second com~onenl, metadiltil, linkcd to implemenied by all information providers. The CnRI resolution system is used for resolving a DOI into a URL as the third component.

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Communication Model for Digital Library in the CMC Environment (CMC 환경에서 디지털도서관의 커뮤니케이션 모형)

  • Cho, Yun-Hee
    • Journal of Information Management
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    • v.30 no.3
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    • pp.27-43
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    • 1999
  • The digital library operated in the environment of computer-mediated-communication offered new successful alternative plans for the field and communication methods of the information services that have been provided by the traditional library and this causes the traditional library to move to the new paradigm. In this situation, the information services of the digital library raised the necessity for the communication channels that would cope actively on the spot and for the extention of information services that would supply an unspecified number of the general public with a considerable extention of information services that neglect time and space. This study looked into the communication channels in general for interactions between the digital library and the users in the environment of computer-mediated-communication and observed patterns of communication chennels that the digital library could supply. For the development of the communication model in the digital library, the study presented the communication model for effective information services.

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A Comparative Study on Cooperative Reference Service: Centering on Korea and Japan (협력형 참고봉사 서비스 비교 연구 - 한국과 일본을 중심으로 -)

  • Cho, Ja-Ne
    • Journal of the Korean Society for Library and Information Science
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    • v.46 no.1
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    • pp.119-139
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    • 2012
  • Due to the inferior condition of local library reference service, an air of indifference about users, and the increase in Internet resources, cooperative reference service in domestic libraries tend to be stagnant. The increase in Internet resources was reconsidered, aside from traditional library reference service, based on question and answer service. It shed new light on the importance of indirect service, which is focused on reliable knowledge base construction. This study analyzed cooperative reference service, which is managed by the Japanese Diet library that pursued indirect service contrary to ours. Based on that, it suggested a new takeoff possibility for Korean cooperative reference service.

The Factors which Should be Considered in Real-time Reference Service and the Effective Way of Using it (실시간 참고서비스의 효과적인 활용방안 및 고려요소)

  • Chung Jae-Young
    • Journal of Korean Library and Information Science Society
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    • v.37 no.3
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    • pp.75-101
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    • 2006
  • This study is about the factors required to be considered in the aspects of policy and operation before introducing the real-time reference service and about the way to use the real-time reference service effectively, The real-time reference service should not be accepted and applied just based on the case of advanced nations without deciding how to apply and use through enough advanced investigation and example analysis. Working out in service policies, selecting appropriate programs. securing service manpower, devising privacy policies, groping the ways of cooperation between libraries, and operating the adequate evaluation system are the factors which should be considered in the policy aspect. Preparation of proper ways of application. operation time, and promotion are the factors which should be considered and reviewed in the operative aspect.

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Elemental Image Synthesis for Integral Imaging Using Phase-shifting Digital Holography

  • Jeong, Min-Ok;Kim, Nam;Park, Jae-Hyeung
    • Journal of the Optical Society of Korea
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    • v.12 no.4
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    • pp.275-280
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    • 2008
  • We propose a method generating elemental images for the integral imaging using 4-step phaseshifting digital holography. Phase shifting digital holography is a way recording the digital hologram by changing the phase of the reference beam and extracting the complex field of the object beam. Since all 3D information is captured by phase-shifting digital holography, the elemental images for any specifications of the lens array can be generated from single phase-shifting digital holography. In experiment, phase-shifting is achieved by rotating half- and quarter- wave plates and the resultant interference patterns are captured by a $3272{\times}2469$ pixel CCD camera with $27{\mu}m{\times}27{\mu}m$ pixel size.

Reference points suitable for evaluation of the additional arch length required for leveling the curve of Spee

  • Cho, Yong-Hwa;Lim, Sung-Hoon;Gang, Sung-Nam
    • The korean journal of orthodontics
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    • v.46 no.6
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    • pp.356-363
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    • 2016
  • Objective: The additional arch length required for leveling (AALL) the curve of Spee (COS) can be estimated by subtracting the two-dimensional (2D) arch circumference, which is the projection of the three-dimensional (3D) arch circumference onto the occlusal plane, from the 3D arch circumference, which represents the arch length after leveling the COS. The purpose of this study was to determine whether the cusp tips or proximal maximum convexities are more appropriate reference points for estimating the AALL. Methods: Sixteen model setups of the mandibular arch with COS depths ranging from 0 mm to 4.7 mm were constructed using digital simulation. Arch circumferences in 2D and 3D were measured from the cusp tips and proximal maximum convexities and used to calculate the AALL. The values obtained using the two reference points were compared with the paired t -test. Results: Although the 3D arch circumference should be constant regardless of the COS depth, it decreased by 3.8 mm in cusp tip measurements and by 0.4 mm in proximal maximum convexity measurements as the COS deepened to 4.7 mm. AALL values calculated using the cusp tips as reference points were significantly smaller than those calculated using the proximal maximum convexities (p = 0.002). Conclusions: The AALL is underestimated when the cusp tips are used as measurement reference points; the AALL can be measured more accurately using the proximal maximum convexities.