• Title/Summary/Keyword: Active Research

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Technique for Estimating the Number of Active Flows in High-Speed Networks

  • Yi, Sung-Won;Deng, Xidong;Kesidis, George;Das, Chita R.
    • ETRI Journal
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    • v.30 no.2
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    • pp.194-204
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    • 2008
  • The online collection of coarse-grained traffic information, such as the total number of flows, is gaining in importance due to a wide range of applications, such as congestion control and network security. In this paper, we focus on an active queue management scheme called SRED since it estimates the number of active flows and uses the quantity to indicate the level of congestion. However, SRED has several limitations, such as instability in estimating the number of active flows and underestimation of active flows in the presence of non-responsive traffic. We present a Markov model to examine the capability of SRED in estimating the number of flows. We show how the SRED cache hit rate can be used to quantify the number of active flows. We then propose a modified SRED scheme, called hash-based two-level caching (HaTCh), which uses hashing and a two-level caching mechanism to accurately estimate the number of active flows under various workloads. Simulation results indicate that the proposed scheme provides a more accurate estimation of the number of active flows than SRED, stabilizes the estimation with respect to workload fluctuations, and prevents performance degradation by efficiently isolating non-responsive flows.

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Classification of White Blood Cell Using Adaptive Active Contour

  • Theerapattanakul, J.;Plodpai, J.;Mooyen, S.;Pintavirooj, C.
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1889-1891
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    • 2004
  • The differential white blood cell count plays an important role in the diagnosis of different diseases. It is a tedious task to count these classes of cell manually. An automatic counter using computer vision helps to perform this medical test rapidly and accurately. Most commercial-available automatic white blood cell analysis composed mainly 3 steps including segmentation, feature extraction and classification. In this paper we concentrate on the first step in automatic white-blood-cell analysis by proposing a segmentation scheme that utilizes a benefit of active contour. Specifically, the binary image is obtained by thresolding of the input blood smear image. The initial shape of active is then placed roughly inside the white blood cell and allowed to grow to fit the shape of individual white blood cell. The white blood cell is then separated using the extracted contour. The force that drives the active contour is the combination of gradient vector flow force and balloon force. Our purposed technique can handle very promising to separate the remaining red blood cells.

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Copper micro/nanostructures as effective SERS active substrates for pathogen detection

  • Ankamwar, Balaprasad;Sur, Ujjal Kumar
    • Advances in nano research
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    • v.9 no.2
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    • pp.113-122
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    • 2020
  • Surface-Enhanced Raman Scattering (SERS) spectroscopy is a multifaceted surface sensitive methodology which exploits spectroscopy-based analysis for various applications. This technique is based on the massive amplification of Raman signals which were feeble previously in order to use them for appropriate identification at qualitative and quantitative in chemical as well as biological systems. This novel powerful technique can be utilized to identify pathogens such as bacteria and viruses. As far as SERS is concerned, one of the most studied problems has been functionalization of SERS active substrate. Metal colloids and nanostructures or microstructures synthesized using noble metals such as Au, Ag and Cu are considered to be SERS active. Silver and gold are extensively used as SERS active substrates due to chemical inertness and stability in air compare to copper. However, use of Cu as a suitable alternative has been taken into account as it is cheap. Herein, we have synthesized air-stable copper microstructures/nanostructures by chemical, electrochemical and microwave-assisted methods. In this paper, we have also discussed the use of as synthesized copper micro/nanostructures as inexpensive yet effective SERS active substrates for the fast identification of micro-organisms like Staphylococcus aureus and Escherichia coli.

5.2 mW 61 dB SNDR 15 MHz Bandwidth CT ΔΣ Modulator Using Single Operational Amplifier and Single Feedback DAC

  • Cho, Young-Kyun;Park, Bong Hyuk;Kim, Choul-Young
    • ETRI Journal
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    • v.38 no.2
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    • pp.217-226
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    • 2016
  • We propose an architecture that reduces the power consumption and active area of such a modulator through a reduction in the number of active components and a simplification of the topology. The proposed architecture reduces the power consumption and active area by reducing the number of active components and simplifying the modulator topology. A novel second-order loop filter that uses a single operational amplifier resonator reduces the number of active elements and enhances the controllability of the transfer function. A trapezoidal-shape half-delayed return-to-zero feedback DAC eliminates the loop-delay compensation circuitry and improves pulse-delay sensitivity. These simple features of the modulator allow higher frequency operation and more design flexibility. Implemented in a 130 nm CMOS technology, the prototype modulator occupies an active area of $0.098mm^2$ and consumes 5.23 mW power from a 1.2 V supply. It achieves a dynamic range of 62 dB and a peak SNDR of 60.95 dB over a 15 MHz signal bandwidth with a sampling frequency of 780 MHz. The figure-of-merit of the modulator is 191 fJ/conversion-step.

Clothing Purchase Behavior of Active Senior -Differences According to Gender and Shopping Orientation Types- (액티브 시니어 소비자들의 의복구매행동 -성별과 쇼핑성향 유형에 따른 비교-)

  • Chae, Jin Mie
    • Fashion & Textile Research Journal
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    • v.22 no.1
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    • pp.25-37
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    • 2020
  • This study investigates the clothing purchase behavior of active seniors in their 50s and 60s. Differences of clothing purchase behaviors were examined according to gender and the group classified by shopping orientation. Data were collected from September 2 to September 9, 2019 using a professional internet research panel; subsequently, 246 sets of useful data were analyzed by descriptive statistics, factor analysis, reliability analysis, t-test, chi-squared test, ANOVA and Duncan-test using SPSS 21.0. The results of this study were as follows. First, there were significant differences in clothing purchase behavior of purchase frequency, purchase item, purchase price, and purchase channel according to gender; therefore marketers need plan different merchandising and retailing strategies between man's wear and woman's wear. Second. the result of cluster analysis by shopping orientation showed that active seniors were categorized into four groups including 'active shopping pursuit', 'economic/pleasure pursuit', 'convenience/brand pursuit', and 'passive shopping pursuit'. Third, there were significant differences in demographic variables such as gender and occupation according to four categorized groups. In addition, the significant differences of clothing purchase behaviors were verified according to four groups. 'Active shopping pursuit' group was shown to make the best use of offline channels and online channels in information research and product purchase.

Active Node Architecture considering He Characteristics of Active Applications (능동 응용의 특성을 고려한 능동 노드 구조)

  • 안상현;김경춘;손선경;손승원
    • Journal of KIISE:Information Networking
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    • v.29 no.6
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    • pp.712-721
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    • 2002
  • The active network is a new networking approach to allow new protocols to be developed easily by solving the limitation of the existing protocol development procedure and the long protocol standardization process. So far many research institutes and universities have proposed active node architectures and active packet formats, but still there are some problems needed to be solved. One of them is the active packet format and the routing approach which consider the requirements of various active applications. Therefore, in this paper, we figure cut the requirements of various active applications and design four types of active packet formats that reflect these requirements and propose routing schemes appropriate for these characteristics. Also we propose an active node architecture which reflect these requirements.

A development of outdoor pants for active senior males (액티브 시니어 남성을 위한 아웃도어 팬츠 개발)

  • Kim, Ji-Eun;Kim, Eun-Kyong
    • Journal of the Korea Fashion and Costume Design Association
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    • v.21 no.2
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    • pp.57-73
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    • 2019
  • This study was carried out to offer basic data that can be used for the production of outdoor pants for active senior males, which is emerging as a new consumer bracket in the rapidly aging society. To this end, this study modified and complemented the patterns of existing outdoor pants for active senior males, that received the most positive evaluations. On the basis of the research and outdoor wear assessment results, this study proposed the matters to consider in the manufacturing of outdoor pants for active senior males. As a result of the existing outdoor wear's wearing assessment, the pants of brand C were revealed to be the best. This study actually designed research outdoor wear by modifying the problematic parts by adding and subtracting spare length or circumference, on parts where fit satisfaction was low, and by referring to the selected brands' patterns. The research outdoor pants were designed by referring to the preferred outdoor types and colors that were revealed in the survey results. The wearing assessment was conducted by comparing the manufactured research outdoor pants and the existing outdoor pants, which were selected as the best outdoor pants. Consequently, this study verified the fit of the research outdoor pants was superior to most items. This study proposed the final patterns of outdoor pants suitable for active senior males through the modification of several items that required some improvements revealed via the wearing assessment of the research outdoor.

Function Analysis for the active surveillance system of urban transit (도시철도의 능동적 감시체계를 위한 기능 분석)

  • An, Tae-Ki;Shin, Jeong-Ryul;Lee, Woo-Dong;Han, Seok-Yoon;Kim, Moon-Hyun
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1027-1028
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    • 2008
  • Most of the urban transit operation company in Korea have a passive surveillance system to monitor the status of the passengers and facilities in the urban transit service area. The surveillance system is based on CCTV, closed circuit television, and several sensors, such as a fire sensor. However, this system has some limitations to prevent and cope with the emergency quickly. So the urban transit operation companies have plans to be change their surveillance system to be active. The active surveillance system has an intelligent function to detect the event predefined by managers automatically. To construct the active surveillance system, there are a standard concept design and a function analysis. In this paper, we propose the classification of the functions of the active surveillance system for urban transit. We divide the functions into five parts, ordinary monitoring, safety monitoring, environment monitoring, administration support, and record management. And we describe the systems related to the every functions to clarify the classified functions.

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Antigenicity Studies of the Aqueous Extract of Red Ginseng in Guinea Pigs

  • Lee, Jong-Wha;Rhee, Man-Hee;Park, Ki-Hyun
    • Archives of Pharmacal Research
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    • v.17 no.3
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    • pp.154-160
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    • 1994
  • The antigenicity of the aqueous extract of red ginseng (ARG) was evaluated using the following assay procedures : 1. active systemic anaphylaxis (ASA) in guinea pigs, 2 active cutaneous anaphylaxis (ACA) in guinea pigs, 3 passive cutaneous anaphylaxis (PCA) in guinea pigs, 2.active cutaneous anaphylaxis (ACA) in guinea pigs, 3. passive cutanepous anaphylaxis (PCA) in guina pigs with serum for guina pigs sensitized with ARG and 4. passive hemagglutination (PHA) with serum from guinea pigs sensitized with ARG. 1. ASA : No anaphylaxis reaction was observed in any of the sensitized guinea pigs by elictitation with ARG. 2. ACA : No skin reaction was observed in sensitized guinea pigs after intrademal injection of ARG. 3. PCA in guinea pigs : PCA titer of sera from all the sensitized animals was less than 10 in eliciation with ARG. 4. PHA reaction : When eythrocytes coated with challenge antigen were added to sensitized sera, the hemagglutination titer was less than 1. These results suggest that ARG has no antigenicity under the conditions used. And the dose levels of ARG employed in the present experiment were confirmed not to suppress immune reactions.

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AC Power Line Conditioner (교류 전력 품질 개선 장치)

  • Kim, Won-Ho;Kim, Jong-Su;Gang, Yu-Ri;Im, Geun-Hui;Kim, Cheol-U
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.48 no.9
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    • pp.498-502
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    • 1999
  • Harmonics and the reactive power related problems in the supply and demand side are increasing with the proliferation of nonlinear loads such as power converters in industrial applications. Filtering options such as passive, active and hybrid filters are countermeasures against these problems. In this study, a novel hybrid active filter topology with a new approach to enhance the system performance is presented. In this study, a novel hybrid active filter topology with a new approach to enhance the system performance is presented. The proposed topology comprised a parallel inverter and a hybrid active filter. It improves the system efficiency and reduces VA ratings, hence, overall filtering cost. The system operation, control and experimental verification on three phase rectifier and/or capacitor loads are presented.

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