• Title/Summary/Keyword: Line inversion

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Genetic Algorithms for Mixed Model Assembly Line Sequencing (혼합모델 조립라인의 생산순서 결정을 위한 유전알고리듬)

  • Kim, Yeo-Geun;Hyun, Chul-Ju
    • Journal of Korean Institute of Industrial Engineers
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    • v.20 no.3
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    • pp.15-34
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    • 1994
  • This paper considers the genetic algorithms(GAs) for the mixed model assembly line sequencing(MMALS) in which the objective is to minimize the overall line length. To apply the GAs to the MMALS, the representation, selection, genetic sequencing operators, and genetic parameters are studied. Especially, the existing sequencing binary operators such as partially map crossover(PMX), cycle crossover(CX), and order crossover (OX) are modified to be suitable for the MMALS, and a new sequencing binary operator called immediate successor relationship crossover (ISR) is introduced. These binary operators mentioned above and/or unary operators such as swap, insertion, inversion, displacement, and splice are compared to find operators which work well in the MMALS. Experimental results indicate that 1) among the binary operators ISR operator is the best, followed by the modified OX, and the modified PMX, with the modified CX being the worst, 2) among the unary operators inversion operator is the best, followed by displacement, swap, and insertion, with splice being the worst, and 3) in general, the unary operators perform better than the binary operators for the MMALS.

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태양활동영역에서 Magnetic Polarity Inversion Line의 기하학적, 물리적 특성에 대한 통계적 연구

  • Lee, Eo-Jin;Park, Seong-Hong;O, Su-Yeon;Lee, Yu
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.114.2-114.2
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    • 2012
  • 태양 광구표면에서 시선방향 자기장 자료를 살펴보면 그 극성이 변하는 지점들이 선의 형태로 보이는데 이것을 Magnetic Polarity Inversion Line(MPIL) 혹은 Neutral Line이라 부른다. 기존의 연구에 의하면 태양활동영역에서 MPIL의 길이가 길수록 플레어 및 코로나물질방출(CME)과 같은 큰 규모의 분출현상들이 일어나는 빈도가 높다는 사실이 보고된 바 있다. 이런 점에서 볼 때 MPIL이 우주환경 예보의 측면에서 중요한 도구가 될 수 있을 것으로 기대된다. 하지만 여전히 MPIL의 기하학적, 물리적 특성 및 그 형성과 진화과정에 대한 이해가 부족한 상황이다. 우리는 본 연구에서 SOHO/MDI 시선방향 자기장 자료를 사용하여 태양활동 23주기에 나타난 308개의 태양활동영역에 대하여 MPIL의 길이, 곡률과 같은 기하학적인 특성을 연구하였고, 또한 MPIL주변의 자기장(평균 자기선속, 총 자기선속 등) 및 magnetic fragment들의 속도장(평균속력, 수렴 및 발산정도, vorticity 등)과 같은 물리적인 특성에 대한 통계적 조사를 수행하였다.

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Temperature Distribution in Ethylene Diffusion Flames Based on Measurement Techniques;Comparison of Thermocouple and Tow-Color Pyrometry (측정방법에 따른 에틸렌 확산화염의 온도분포;열전대 및 이색법 측정 결과 비교)

  • Lee, Won-Nam;Na, Yong-Dae;Lee, Bum-Ky;Park, Seong-Nam
    • 한국연소학회:학술대회논문집
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    • 2000.12a
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    • pp.175-182
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    • 2000
  • Flame temperatures were measured and compared using a rapid insertion technique and a two-color pyrometry with Abel inversion process in co-flow ethylene diffusion flames. The measured line-of-sight temperature showed very limited usefulness in understanding the detailed soot formation/oxidation process in a co-flow diffusion flame. The flame temperatures could be measured with reasonable accuracy for the soot laden regions in ethylene diffusion flames using two-color pyrometry with an Abel inversion technique. Two-color-pyrometry with Abel inversion was demonstrated as a useful temperature measurement technique for co-flow diffusion flames, expecially under pressure conditions, where a thermocouple is not applicable. The soot volume fraction could be also obtained using tow-color pyrometry with Abel inversion, which provides important information for understanding the soot formation/oxidation mechanism in diffusion flames.

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The Effect of Inversion Layer on the Land and Sea Breeze Circulations near the Gangneung (역전층이 강릉시 주변 해륙풍 순환에 미치는 영향 연구)

  • NamGung, Ji-Yeon;Yu, Jae-Hoon;Kim, Nam-Won;Choi, Man-Kyu;Ham, Dong-Ju;Kim, Hoon-Sang;Jang, You-Jung;Choi, Eun-Kyung
    • Atmosphere
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    • v.15 no.4
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    • pp.229-239
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    • 2005
  • The effect of inversion layer on the land and sea breeze near the Gangneung city was investigated. The land and sea breeze occurrence days were selected, and the height and the intensity of inversion layer were calculated with the upper air observational data of the Sokcho Station. The relationships between the temperature variation near the Gangneung and the inflow time, inland penetration and the inflow depth of the land and sea breeze were also analyzed. And the Gangwon Short-range prediction system was verified with the comparison of surface stream line by the Gangwon short-range prediction system with the AWS wind vector data. It was revealed that the inversion layer tended to block the sea breeze, shorten the inland penetration distance and lower the inflow depth, causing the temperature rise. The comparison and analysis of surface steam line by the Gangwon short-range prediction system and the AWS wind vector showed that the system quite well simulated the sea breeze, thus the system could be well utilized in the prediction of land and sea breeze.

Geoelectrical structure of Jeju Island deduced from 2D inversion of AMT and MT data

  • Choi, Ji-Hyang;Kim, Hee-Joon;Nam, Myung-Jin;Lee, Tae-Jong;Lee, Seong-Kon;Song, Yoon-Ho;Suh, Jung-Hee
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.257-260
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    • 2007
  • Two-dimensional (2D) interpretation of MT and AMT data observed in 2004 in Jeju Island is made using two inversion schemes developed by Uchida (1993) and Lee et al. (2002). These interpretations show that the subsurface of Jeju consists of roughly three layers. Reconstructed images along lines E and W reveal that the conductive layer beneath the topmost resistive layer of lava plateau can be a sediment layer. The geoelectrical structure along line E is more complex than that along line W, especially near Mt. Halla. The Uchida’s (1993) scheme gives reasonable images, but much more time-consuming than that of Lee et al. (2002).

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A Spectropolarimetric Investigation of the Photospheric and Chromospheric Layers of Sunspots

  • Kim, Hyunnam;Solanki, Sami.K.;Lagg, Andreas;Kim, Kap-Sung;Lim, Daye;Choe, G.S.
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.128.2-128.2
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    • 2012
  • Spectro-polarimetry is the most powerful technique for deducing the magnetic structure of the Sun. Stokes vector allow us to infer the physical conditions in the solar atmosphere prevailing during the line formation. Inversion codes are the main tool to extract this information from the Stokes spectra. This study will focus on measurements of the chromospheric He I 1083.0 nm triplet and the photospheric Si I 1082.7 nm line. A spectropolarimetric data set of sunspots, obtained with the German Vacuum Tower Telescope (VTT) at the Teide observatory on Tenerife, is analyzed using an inversion technique. We will introduce the German Vacuum Tower Telescope and the inversion code HeLix, and will show data sets that are analyzed by HeLix. Finally I made variety plots and maps for understanding photospheric and chromospheric layers of sunspots.

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A Low-Power Two-Line Inversion Method for Driving LCD Panels

  • Choi, Sung-Pil;Kwon, Kee-Won;Chun, Jung-Hoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.4
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    • pp.481-487
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    • 2016
  • A new two-line based inversion driving method is introduced for low power display-driver ICs. By inserting a timing offset between the chopper stabilization and the alternation of LCD polarity, we can reduce power consumption without noticeable degradation in the display quality. By applying the proposed scheme to 12" LCD applications, we achieved 7.5% and 27% power saving in the display-driver IC with white and black patterns, respectively.

Low-Power IoT Microcontroller Code Memory Interface using Binary Code Inversion Technique Based on Hot-Spot Access Region Detection (핫스팟 접근영역 인식에 기반한 바이너리 코드 역전 기법을 사용한 저전력 IoT MCU 코드 메모리 인터페이스 구조 연구)

  • Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.11 no.2
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    • pp.97-105
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    • 2016
  • Microcontrollers (MCUs) for endpoint smart sensor devices of internet-of-thing (IoT) are being implemented as system-on-chip (SoC) with on-chip instruction flash memory, in which user firmware is embedded. MCUs directly fetch binary code-based instructions through bit-line sense amplifier (S/A) integrated with on-chip flash memory. The S/A compares bit cell current with reference current to identify which data are programmed. The S/A in reading '0' (erased) cell data consumes a large sink current, which is greater than off-current for '1' (programmed) cell data. The main motivation of our approach is to reduce the number of accesses of erased cells by binary code level transformation. This paper proposes a built-in write/read path architecture using binary code inversion method based on hot-spot region detection of instruction code access to reduce sensing current in S/A. From the profiling result of instruction access patterns, hot-spot region of an original compiled binary code is conditionally inverted with the proposed bit-inversion techniques. The de-inversion hardware only consumes small logic current instead of analog sink current in S/A and it is integrated with the conventional S/A to restore original binary instructions. The proposed techniques are applied to the fully-custom designed MCU with ARM Cortex-M0$^{TM}$ using 0.18um Magnachip Flash-embedded CMOS process and the benefits in terms of power consumption reduction are evaluated for Dhrystone$^{TM}$ benchmark. The profiling environment of instruction code executions is implemented by extending commercial ARM KEIL$^{TM}$ MDK (MCU Development Kit) with our custom-designed access analyzer.

MULTILAYER SPECTRAL INVERSION OF SOLAR Hα AND CA II 8542 LINE SPECTRA WITH HEIGHT-VARYING ABSORPTION PROFILES

  • Chae, Jongchul;Cho, Kyuhyoun;Kang, Juhyung;Lee, Kyoung-Sun;Kwak, Hannah;Lim, Eun-Kyung
    • Journal of The Korean Astronomical Society
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    • v.54 no.5
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    • pp.139-155
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    • 2021
  • We present an updated version of the multilayer spectral inversion (MLSI) recently proposed as a technique to infer the physical parameters of plasmas in the solar chromosphere from a strong absorption line. In the original MLSI, the absorption profile was constant over each layer of the chromosphere, whereas the source function was allowed to vary with optical depth. In our updated MLSI, the absorption profile is allowed to vary with optical depth in each layer and kept continuous at the interface of two adjacent layers. We also propose a new set of physical requirements for the parameters useful in the constrained model fitting. We apply this updated MLSI to two sets of Hα and Ca II line spectral data taken by the Fast Imaging Solar Spectrograph (FISS) from a quiet region and an active region, respectively. We find that the new version of the MLSI satisfactorily fits most of the observed line profiles of various features, including a network feature, an internetwork feature, a mottle feature in a quiet region, and a plage feature, a superpenumbral fibril, an umbral feature, and a fast downflow feature in an active region. The MLSI can also yield physically reasonable estimates of hydrogen temperature and nonthermal speed as well as Doppler velocities at different atmospheric levels. We conclude that the MLSI is a very useful tool to analyze the Hα line and the Ca II 8542 line spectral daya, and will promote the investigation of physical processes occurring in the solar photosphere and chromosphere.