• Title/Summary/Keyword: I-O analysis

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Analysis of O-J-I-P Transients from Four Subtropical Plant Species for Screening of Stress Indicators under Low Temperature (저온스트레스 지표 선발을 위한 아열대성 식물 4종의 O-J-I-P곡선 분석)

  • Oh Soonja;Koh Seok Chan
    • Journal of Environmental Science International
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    • v.14 no.4
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    • pp.389-395
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    • 2005
  • The changes of O-J-I-P transients were investigated using leaves of four subtropical plant species (Crinum asiaticum var. japonicum, Osmanthus insularis, Chloranthus glaber and Asplenium antiquum) under the natural conditions in winter, in order to select the stress indicators for diagnosing physiological states of plants under low temperature. In the O-J-I-P transients of these species, the fluorescence intensity was found to be higher in O-step and lower in P-step in winter than in summer. Particularly, the fluorescence intensity of the P-step in Crinum asiaticum var. japonicum was lower than those of other three plant species, indicating that Crinum asiaticum var. japonicum is the most sensitive to low temperature. Of the chlorophyll fluorescence parameters derived from O-J-I-P transients of four subtropical plants, Fm, Fv/Fo, ABS/CS, TRo/CS, $\phi_{po}$ and $\phi_{po}/(1-\phi_{po})$ decreased significantly with the increase of Fo, Sm, N, EToICS, ETo/RC and $\psi_o/(1-\psi_o)$ depending on temperature drop in winter. Therefore, these parameters could be used as indicators for estimating low temperature stress and diagnosing physiological states of plants under the natural conditions in winter.

Analysis of Chip Performance by Core and I/O SSN Noise on DLL Board (DLL 보드 상에 코어 및 I/O 잡음에 의한 칩의 성능 분석)

  • Cho, Sung-Gon;Ha, Jong-Chan;Wee, Jae-Kyung
    • Journal of the Microelectronics and Packaging Society
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    • v.13 no.4
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    • pp.9-15
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    • 2006
  • This paper shows the impedance profile of PEEC(Partial Equivalent Electrical Circuit) PDN(Power Distribution Networks) including core and I/O circuit. Through the simulated results, we find that the core power noise having connection with I/O power is affected by I/O switching. Also, using designed $74{\times}5inch$ DLL(Delay Locked Loop) test board, we analyzed the effect of power noise on operation region of chip. Jitter of a DLL measure for frequency of $50{\sim}400MHz$ and compared with impedance obtained result of simulation. Jitter of a DLL are increased near about frequency of 100MHz. It is reason that the resonant peak of PDNs has an impedance of more the 1ohm on 100MHz. we present the impedance profile of a chip and board for the decoupling capacitor reduced the target impedance. Therefore, power supply network design should be considered not only decoupling capacitors but also core switching current and I/O switching current.

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Analysis of Flood Control Capacity of Agricultural Reservoir Based on SSP Climate Change Scenario (SSP 기후변화 시나리오에 따른 농업용 저수지 홍수조절능력 분석)

  • Kim, Jihye;Kwak, Jihye;Hwang, Soonho;Jun, Sang Min;Lee, Sunghack;Lee, Jae Nam;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.5
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    • pp.49-62
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    • 2021
  • The objective of this study was to evaluate the flood control capacity of the agricultural reservoir based on state-of-the-art climate change scenario - SSP (Shared Socioeconomic Pathways). 18 agricultural reservoirs were selected as the study sites, and future rainfall data based on SSP scenario provided by CMIP6 (Coupled Model Intercomparison Project 6) was applied to analyze the impact of climate change. The frequency analysis module, the rainfall-runoff module, the reservoir operation module, and their linkage system were built and applied to simulate probable rainfall, maximum inflow, maximum outflow, and maximum water level of the reservoirs. And the maximum values were compared with the design values, such as design flood of reservoirs, design flood of direct downstream, and top of dam elevation, respectively. According to whether or not the maximum values exceed each design value, cases were divided into eight categories; I-O-H, I-O, I-H, I, O-H, O, H, X. Probable rainfall (200-yr frequency, 12-h duration) for observed data (1973~2020) was a maximum of 445.2 mm and increased to 619.1~1,359.7 mm in the future (2011~2100). For the present, 61.1% of the reservoirs corresponded to I-O, which means the reservoirs have sufficient capacity to discharge large inflow; however, there is a risk of overflowing downstream due to excessive outflow. For the future, six reservoirs (Idong, Baekgok, Yedang, Tapjung, Naju, Jangsung) were changed from I-O to I-O-H, which means inflow increases beyond the discharge capacity due to climate change, and there is a risk of collapse due to dam overflow.

Android Boot Sequence I/O Pattern Analysis through Linux Kernel Profiling Techniques (Linux Kernel Profiling 기법을 통한 안드로이드 부팅 시퀀스 I/O 패턴 분석)

  • Yu, Jun-Young;Lee, Sung-Woo;Lim, Seung-Ho
    • Proceedings of the Korea Information Processing Society Conference
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    • 2011.11a
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    • pp.33-35
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    • 2011
  • 최근 안드로이드 플랫폼은 성능 개선의 많은 이슈를 가지고 있다. 그 중 안드로이드 부팅 시퀀스부분이 중요한 부분으로 차지하고 있다. 안드로이드 플랫폼 부팅 과정의 속도 저하가 발생 되는 부분은 블록 I/O 시스템이다. 본 논문에서는 리눅스 블록 레이어의 I/O를 tracing 해주는 blktrace에 대해 소개를 하고 그 기법을 통해 안드로이드 부팅 시퀀스의 I/O 패턴을 분석하고, 개선 방안을 고찰한다.

Discharge analysis of SrO- and SrCaO-PDP operated at lower voltage

  • Uchida, G.;Uchida, S.;Yano, T.;Awaji, N.;Kajiyama, H.;Shinoda, T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.177-180
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    • 2009
  • Here is presented the measurement on SrO- and SrCaO-PDP operated at lower voltage. SrO- and SrCaO-PDP attain high luminous efficacy at low voltage, where the breakdown voltage is 30 % lower than that of the ordinary MgO-PDP. A one-dimensional fluid model is applied for the simulation of PDP discharge. High VUV radiation efficiency is confirmed at high ${\gamma}_i$ and both low and high $V_s$ as in the experiment. Discharge analysis in simulation also shows that the high ${\gamma}_i$ protective layer leads to high plasma density especially near the cathode electrode, being responsible for high efficiency.

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Power Loss and Electro-Magnetic Characteristics of Ni-Cu-Zn Ferrites (Ni-Cu-Zn페라이트의 손실과 자성 특성)

  • Otsuki E.;Kim Jeong-Su
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2004.12a
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    • pp.3-11
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    • 2004
  • The power loss analysis was carried out for Ni-Cu-Zn ferrite samples with different content of NiO and ZnO. The power loss, Pcv decreases monotonically wi increasing temperature and attains to a certain value at around $100\~120$ degrees Celsius. The frequency dependence of Pcv can be explained by $Pcv\~f^n$', and n is independent of the frequency, f up to 1MHz. The Pcv decreases with an increase in ZnO/NiO. The Pcv was separated to hysteresis loss, Ph and residual loss, (Pcv-Ph). The temperature characteristics and compositional dependence of Pcv can be attributed to the Ph, while (Pcv-Ph) is not affected by both temperature and ZnO/NiO. By analyzing temperature and composition dependence of Ph and initial permeability, ${\mu}^i$ following equations could be formularized. $${\mu}_i{\mu}o=I_x\;^2/(K_1+bs_ol_s)\;\;\;\;(1)$$ $Wh=13.5(I_s\;^2/{\mu}_i{\mu}_o)\;\;\;\;(2)$$ Were ${\mu}_o$ is permeability of vacuum, $I_s$ saturation magnetization, $K_1$ anisotropy constant, $S_o$ internal heterogeneous stress, $I_s$, magnetostriction constant, b unknown constant. Wh hysteresis loss per one cycle of excitation (Ph: Wh*f). Steinmetz constant of Ni-Cu-Zn ferrites, $m=1.64\~2.2$ is smaller than the one of Mn-Zn ferrites, which suggests the difference of loss mechanism between these materials.

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A Log-based Analysis on the Characteristics and Structure of MPI-IO (MPI-IO를 위한 로그 기반 특성 및 구조 분석)

  • Cha, Kwangho
    • Proceedings of the Korea Information Processing Society Conference
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    • 2013.05a
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    • pp.114-116
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    • 2013
  • 메시지 전달 방식의 병렬 프로그래밍에서 사용되는 MPI는 프로그램의 확장성 보장에 적합한 MPI-IO라는 파일 I/O 방법을 제공하고 있다. MPI-IO는 동시적인 병렬 I/O 수행으로 인한 성능 저하를 최소화하기 위하여 내부적으로 데이터 재정렬 후 I/O를 수행한다. 본 연구에서는 이와 같은 MPI-IO의 내부 처리과정을 기록하기 위한 방안을 강구하여 실행 시간 로그를 기록하였고 이를 바탕으로 MPI-IO의 특성을 살펴보았다.

Performance Evaluation and Analysis of NVM Storage for Ultra-Light Internet of Things (초경량 사물인터넷을 위한 비휘발성램 스토리지 성능평가 및 분석)

  • Lee, Eunji;Yoo, Seunghoon;Bahn, Hyokyung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.6
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    • pp.181-186
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    • 2015
  • With the rapid growth of semiconductor technologies, small-sized devices with powerful computing abilities are becoming a reality. As this environment has a limit on power supply, NVM storage that has a high density and low power consumption is preferred to HDD or SSD. However, legacy software layers optimized for HDDs should be revisited. Specifically, as storage performance approaches DRAM performance, existing I/O mechanisms and software configurations should be reassessed. This paper explores the challenges and implications of using NVM storage with a broad range of experiments. We measure the performance of a system with NVM storage emulated by DRAM with proper timing parameters and compare it with that of HDD storage environments under various configurations. Our experimental results show that even with storage as fast as DRAM, the performance gain is not large for read operations as current I/O mechanisms do a good job hiding the slow performance of HDD. To assess the potential benefit of fast storage media, we change various I/O configurations and perform experiments to quantify the effects of existing I/O mechanisms such as buffer caching, read-ahead, synchronous I/O, direct I/O, block I/O, and byte-addressable I/O on systems with NVM storage.

Characterization of Alumina Gel Prepared by Hydrolysis of Al(OC3H7i)3 (Al(OC3H7i)3의 가수분해로부터 얻어진 Al2O3 겔의 특성에 관한 연구)

  • 이서우;문종수;조성백
    • Journal of the Korean Ceramic Society
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    • v.25 no.2
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    • pp.89-94
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    • 1988
  • Alumina gel was prepared by the hydrolysis of aluminum isopropoxide Al(OC3H7i)3 at low temperature. Sample were calcined at the various temperatures for 10 houres in the electric furnace, respectively. In order to investigate the various propertis-thermal properties, pore size and distribution, and the transition of crystals, infrared spectroscopy, thermal analysis, particle size analysis, scanning electron microscopy, and porosimetry were employed. Transparent alumina gel was opalized at 1200$^{\circ}C$. Porosity was about 87% with pores below 0.7$\mu\textrm{m}$ and 55% at 1200$^{\circ}C$. The gel was transformed along the rising of temperature as follows; Boehmite\longrightarrow$\delta$-Al2O3\longrightarrow$\theta$\longrightarrowAl2O3\longrightarrow${\alpha}$-Al2O3.

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Research for Efficient Massive File I/O on Parallel Programs (병렬 프로그램에서의 효율적인 대용량 파일 입출력 방식의 비교 연구)

  • Hwang, Gyuhyeon;Kim, Youngtae
    • Journal of Internet Computing and Services
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    • v.18 no.2
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    • pp.53-60
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    • 2017
  • Since processors are handling inputs and outputs independently on distributed memory computers, different file input/output methods are used. In this paper, we implemented and compared various file I/O methods to show their efficiency on distributed memory parallel computers. The implemented I/O systems are as following: (i) parallel I/O using NFS, (ii) sequential I/O on the host processor and domain decomposition, (iii) MPI-IO. For performance analysis, we used a separated file server and multiple processors on one or two computational servers. The results show the file I/O with NFS for inputs and sequential output with domain composition for outputs are best efficient respectively. The MPI-IO result shows unexpectedly the lowest performance.