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Stabilizationof a sagnac interferometric optical fiber current sensor (Sagnac 간섭계형 광섬유 광전류센서의 안정화 방법)

  • 강현서;이종훈;송정태;이경식;김철중
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.7
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    • pp.1607-1612
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    • 1997
  • A new method of stabilizing a Sagnac optical fiber current sensor is presented. This method is characterized by creating aproper amount of circular birefringence the fibersagnac, whose correaponding value of rotation angle is (m+1/2)$\pi$-$2\Psi$, removes the effect of linear birefringence and leads to achieve good stability. Using the technique the stability of the current sensor was improved more than 10 times to within ${\pm}2.3{%}$ at 300Arms.

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The CRISPR Growth Spurt: from Bench to Clinic on Versatile Small RNAs

  • Bayat, Hadi;Omidi, Meysam;Rajabibazl, Masoumeh;Sabri, Suriana;Rahimpour, Azam
    • Journal of Microbiology and Biotechnology
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    • v.27 no.2
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    • pp.207-218
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    • 2017
  • Clustered regulatory interspaced short palindromic repeats (CRISPR) in association with CRISPR-associated protein (Cas) is an adaptive immune system, playing a pivotal role in the defense of bacteria and archaea. Ease of handling and cost effectiveness make the CRISPR-Cas system an ideal programmable nuclease tool. Recent advances in understanding the CRISPR-Cas system have tremendously improved its efficiency. For instance, it is possible to recapitulate the chronicle CRISPR-Cas from its infancy and inaugurate a developed version by generating novel variants of Cas proteins, subduing off-target effects, and optimizing of innovative strategies. In summary, the CRISPR-Cas system could be employed in a number of applications, including providing model systems, rectification of detrimental mutations, and antiviral therapies.

Geometrical Building Analysis for Outdoor Environment Understanding of Autonomous Navigation Robot (자율주행 로봇의 외부환경 이해를 위한 기하학적인 빌딩 분석)

  • Kim, Dae-Nyeon;Trinh, Hoang-Hon;Jo, Kang-Hyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.3
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    • pp.277-285
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    • 2010
  • This paper describes an approach to analyze geometrical information of building images for understanding outdoor environment of autonomous navigation robot. Line segments and color information are used to classily a building with the other objects such as sky, trees, and roads. The line segments and their two neighboring regions are extracted from detected edges in image. The model of line segment (MLS) consists of color information of neighbor regions. This model rules out the line segments of non-building face. A building face converges into dominant vanishing points (DVPs) which include one vertical point and one of five horizontal points in maximum. The intersection of vertical and horizontal lines creates a facet of building. The geometrical characteristics such as the center coordinates, area, aspect ratio and aligned coexistence are used for extracting the windows in the building facet. In experiments, 150 building faces and 1607 windows were detected from the database of outdoor environment. We found that this result shows 94.46% detection rate. These experimental images were all taken in Ulsan metropolitan city in Korea under difference of viewpoints, daytime, camera system and weather condition.

Characteristics of Flow past a Sphere in Uniform Shear (균일 전단유동 내에 위치한 구 주위의 유동특성)

  • Kim, Dong-Joo;Choi, Hyung-Seok;Choi, Hae-Cheon
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1607-1612
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    • 2004
  • Numerical simulations are performed to investigate the characteristics of flow past a sphere in uniform shear. The Reynolds numbers considered are Re=300, 425 and 480 based on the inlet center velocity and sphere diameter. The non-dimensional shear rate K of the inlet uniform shear is varied from 0 to 0.15. At Re=300, the head of the hairpin vortex loop always locates on the high-velocity side in uniform shear, and the flow maintains the planar symmetry. At Re=425 and 480, the irregularity in the location and strength of the hairpin vortex appearing in uniform inlet flow is much reduced in uniform shear, but the flows still keep the asymmetry for most inlet shear rates. However, in the cases of K=0.075 and 0.1 at Re=425, the flows become planar symmetric and their characteristics of the evolution of the hairpin vortex loops are different from those of asymmetric flows. A hysteresis phenomenon switching from the planar symmetry to the asymmetry (or vice versa) depending on the initial condition is also observed at Re=425.

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A Study on the Implementation of Point-to-Point Relay System for Digital LMDS System (디지털 LMDS 시스템을 위한 점대점 중계망 시스템 구현에 관한 연구)

  • 장태화;방효창;정철종;김원후
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1601-1607
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    • 1999
  • LMDS(Local Multipoint Distribution Service) is a broadband wireless transmission system in millimeter wave frequency. LMDS system is consisted with relay system to connect between head-end and hub and distribution system to connect between hub and subscribers. In this study, we develop point-to-point relay system to use back-bone system n LMDS network. We develop STM-1 transceiver over 27GHz and analyze the system performance. We can get the similar measurement results comparing the theoretical results and then prove that this system can fit LMDS back-bone network requirement. This is the first system in Korea and we expect this system can apply the various network.

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Impact of Four Wave Mixing on Manchester Coded ASK Multichannel Optical Communication System (Manchester Coded ASK 다중채널 광통신 시스템의 Four Wave Mixing 에 대한 영향)

  • Lee, Ho-Joon;Leonid G. Kazovsky
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.11
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    • pp.1607-1617
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    • 1993
  • The performance of Manchester-coded ASK optical wavelength division multiplexing(WDM) systems is evaluated laking into account the shot noise and the four wave mixing(FWM) caused by fiber nonlinearities. The result is compared to conventional non-return-to-zero(NRZ) systems for ASK modulation formats. Further, the dynamic range, defined as the ratio of the maximum input power(limited by the FWM), to the minimum input power(limited by receiver sensitivity), is evaluated. For 1.55 rm 16 channel WDM systems, the dynamic range of ASK Manchester coded systems shows a 2.0 dB improvement with respect to the NRZ. This result holds true for both dispersion-shifted fiber and conventional fiber it has been obtained for 10 GHz channel spacing, 1 Gbps/channel bit rate.

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High Speed RZ-Format Transmission Using Very Short Pulses and the Chromatic Dispersion of the Transmission Fiber (매우 짧은 펄스를 이용한 RZ 포맷 광전송의 성능과 전송용 광섬유의 색 분산과의 상관관계)

  • 박상규;정제명
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11B
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    • pp.1607-1611
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    • 2001
  • The dependence of the performance of 40-Gb/s optical transmission using short pulses on the fiber chromatic dispersion is numerically studied. When very short pulses are used, the wide spectrum of the optical signal and the chromatic dispersion of the fiber interact in such a way that results in the reduction of nonlinear impairments of the transmission performance. The degree of this reduction is determined by the combined effects of chromatic dispersion of the fiber and the strength of the optical signal and the transmission distance. When 3ps-long pulses were used for the transmission, the eye-closure penalty was highest with the dispersion D=4ps/nm/km.

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Similarity Measure and Clustering Technique for XML Documents by a Parent-Child Matrix (부모-자식 행렬을 사용한 XML 문서 유사도 측정과 군집 기법)

  • Lee, Yun-Gu;Kim, Woosaeng
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.7
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    • pp.1599-1607
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    • 2015
  • Recently, researches have been developing efficient techniques for accessing, querying, and managing XML documents which are frequently used in the Internet. In this paper, we propose a parent-child matrix to cluster XML documents efficiently. A parent-child matrix analyzes both the content and structural features of an XML document. Each cell of a parent-child matrix has either the value of a node in an XML tree or the value of a child node, where a parent-child relationship exists in the XML tree. Then, the similarity between two XML documents can be measured by the similarity between two corresponding parent-child matrices. The experiment shows that our proposed method has good performance.

A Study on the Figures of Viscera (臟腑圖) in Sancaituhui (《三才圖會》 encyclopaedia illustrations about the all things in nature) by Wang Qi (王圻) of Ming-Dynasty (명대(明代) 왕기(王圻)의 《삼재도회(三才圖會)》 장부도(臟腑圖)에 대한 고찰(考察))

  • Lee, Myeong-Cheol;Park, Kyoung Nam;Maeng, Woong Jae
    • The Journal of Korean Medical History
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    • v.20 no.2
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    • pp.149-168
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    • 2007
  • This study compared the figures of viscera (臟腑圖) in the seventh volume titled "Body" of Sancaituhui (三才圖會), the illustrated Encyclopedia published in the Ming Dynasty (明代), and the figures of viscera in Leijingtuyi (類經圖翼). One hundred and six volume Sancaituhui was compiled by Wang Qi (王圻) and his son Wang Siyi (王思義) in the Ming Dynasty. It was first published in 1607 and republished in 1609. Sancaituhui is somewhat different from other existing medical books in terms of form and content. Thus, this study examined the difference. Another comprehensive medical book, Leijingtuyi, was written by Zhang Jing-yue (張景岳) in 1624. Both Sancaituhui and Leijingtuyi were published in China before Terrenz's Taixirenshenshuogai (泰西人身說槪), the book which first introduced Western anatomy. Therefore, this study accessed the two medical books to examine the development of figures of viscera before the instruction of Western medicine.

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The Correlation between Power Error and Velocity Error according to the Condition and Frequency of Self-Controlled Feedback during Knee Extension

  • Yoon, Jung Gyu
    • Journal of International Academy of Physical Therapy Research
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    • v.9 no.4
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    • pp.1602-1607
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    • 2018
  • This study examined the correlation between power error (PE) and velocity error (VE) according to the condition and frequency of self-controlled feedback (SCF) during knee extension. One hundred participants were randomly assigned to 30% SCF, 70% SCF, 30% yoked feedback (YF), 70% YF and control group, respectively. The SCF group was provided with feedback when they requested it, whereas the YF group did not influence the feedback schedule. Participants in the control group were not given any visual feedback during the experiment. The isotonic, isometric, and isokinetic dynamometer (PRIMUS RS, BTE, USA) was used to measure the power and velocity error during knee extension. The collected data was analyzed using a Pearson test and SPSS 21.0. The correlation between PE and VE according to the condition and frequency of feedback on each phase during knee extension was significant. Both PE and VE were significantly higher when the feedback was provided with high frequency, passive, and no feedback. Our study suggests that application of SCF can help to improve the proprioception of the healthy person while reducing errors through low frequency and active feedback.