• Title/Summary/Keyword: tail distribution

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Development of Fishway Assessment Model based on the Fishway Structure, Hydrology and Biological Characteristics in Lotic Ecosystem

  • Choi, Ji-Woong;Park, Chan-Seo;An, Kwang-Guk
    • Journal of Ecology and Environment
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    • v.39 no.1
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    • pp.71-80
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    • 2016
  • The main goal of this study is to develop a multi-metric fishway assessment model (Mm-FA) and evaluate the efficiency of fishway. The Mm-FA model has three major fishway components with nine metrics: structural characteristics, hydraulic/hydrologic features, and biological attributes. The model was developed for diagnosing and assessing fishway efficiency and tested to Juksan Weir at the Yeongsan River Watershed. Structural characteristics of fishway included slope of the fishway (M1), ratios of fishway width to stream width (M2), and the proportion of orifice clogging and orifice size (M3). Hydraulic/hydrologic characteristics included depth of fishway entrance head (M4), depth of exit tail (M5), and current velocity of inner fishway (M6). Biological characteristics included fish species ratio of inner fishway to upper-lower weir (M7), fish length distribution (M8), and the proportion of migratory fish species to the total number of species (M9). Overall, the assessment of fishway efficiency showed the total score of the Mm-FA model was 25 in the Juksan Weir, indicating "good condition" by the criteria of the five-level classification system. The Mm-FA model may be used as a key tool for the assessment of fishway efficiency, especially on the 16 weirs constructed for the "Four Rivers Restoration Project" after a partial calibration of Mm-FA model.

POWER SPECTRUM ANALYSIS OF THE OMC1 IMAGE AT 1.1MM WAVELENGTH

  • Youn, So-Young;Kim, Sung-Eun
    • Journal of The Korean Astronomical Society
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    • v.45 no.4
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    • pp.93-99
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    • 2012
  • We present a 1.1mm emission map of the OMC1 region observed with AzTEC, a new large-format array composed of 144 silicon-nitride micromesh bolometers, that was in use at the James Clerk Maxwell Telescope (JCMT). These AzTEC observations reveal dozens of cloud cores and a tail of filaments in a manner that is almost identical to the submillimeter continuum emission of the entire OMC1 region at 450 and $850{\mu}m$. We perform Fourier analysis of the image with a modified periodogram and the density power spectrum, which provides the distribution of the length scale of the structures, is determined. The expected value of the periodogram converges to the resulting power spectrum in the mean squared sense. The present analysis reveals that the power spectrum steepens at relatively smaller scales. At larger scales, the spectrum flattens and the power law becomes shallower. The power spectra of the 1.1mm emission show clear deviations from a single power law. We find that at least three components of power law might be fitted to the calculated power spectrum of the 1.1mm emission. The slope of the best fit power law, ${\gamma}{\approx}-2.7$ is similar to those values found in numerical simulations. The effect of beam size and the noise spectrum on the shape and slope of the power spectrum are also included in the present analysis. The slope of the power law changes significantly at higher spatial frequency as the beam size increases.

An Exploratory Analysis on the User Response Pattern and Quality Characteristics of Marketing Contents in the SNS of Regional Government (지역마케팅 콘텐츠의 사용자 반응패턴과 품질특성에 관한 탐색적 분석: 지방자치단체가 운영하는 SNS를 중심으로)

  • Jeong, Yeon-Su;Jeong, Dae-Yul
    • The Journal of Information Systems
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    • v.26 no.4
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    • pp.419-442
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    • 2017
  • Purpose The purpose of this study is to explore the pattern of user response and it's duration time through social media content response analysis. We also analyze the characteristics of content quality factors which are associate with the user response pattern. The analysis results will provide some implications to develop strategies and schematic plans for the operator of regional marketing on the SNS. Design/methodology/approach This study used mixed methods to verify the effects and responses of social media contents on the users who have concerns about regional events such as local festival, cultural events, and city tours etc. Big data analysis was conducted with the quantitative data from regional government SNSs. The data was collected through web crawling in order to analyze the social media contents. We especially analyzed the contents duration time and peak level time. This study also analyzed the characteristics of contents quality factors using expert evaluation data on the social media contents. Finally, we verify the relationship between the contents quality factors and user response types by cross correlation analysis. Findings According to the big data analysis, we could find some content life cycle which can be explained through empirical distribution with peak time pattern and left skewed long tail. The user response patterns are dependent on time and contents quality. In addition, this study confirms that the level of quality of social media content is closely relate to user interaction and response pattern. As a result of the contents response pattern analysis, it is necessary to develop high quality contents design strategy and content posting and propagation tactics. The SNS operators need to develop high quality contents using rich-media technology and active response contents that induce opinion leader on the SNS.

Homing and Restorative Effects of Bone Marrow-Derived Mesenchymal Stem Cells on Cisplatin Injured Ovaries in Rats

  • Liu, Jiabin;Zhang, Haiying;Zhang, Yun;Li, Nan;Wen, Yuku;Cao, Fanglei;Ai, Hao;Xue, Xiaoou
    • Molecules and Cells
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    • v.37 no.12
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    • pp.865-872
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    • 2014
  • Premature ovarian failure (POF) is a long-term adverse effect of chemotherapy treatment. However, current available treatment regimens are not optimal. Emerging evidence suggests that bone marrow-derived mesenchymal stem cells (BMSCs) could restore the structure and function of injured tissues, but the homing and restorative effects of BMSCs on chemotherapy injured ovaries are still not clear. In this study, we found that granulosa cell (GC) apoptosis induced by cisplatin was reduced when BMSCs were migrated to granulosa cells (GCs) in vitro. Chemotherapy-induced POF was induced by intraperitoneal injection of cisplatin in rats. BMSCs labeled with enhanced green fluorescent protein (EGFP) were injected into the rats via the tail vein to investigate the homing and distribution of BMSCs in vivo. The number of BMSCs in the ovarian hilum and medulla was greater than in the cortex, but no BMSCs were found in the follicles and corpus lutea. In addition, the BMSCs treatment group's antral follicle count and estradiol levels increased after 30 days, compared with the POF group. Hence, our study demonstrates that intravenously delivered BMSCs can home to the ovaries, and restore its structure and function in POF model rats.

Effect of Different Lighting Sources on Behavior and Growth of Weanling Pigs

  • Glatz, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.2
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    • pp.280-287
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    • 2001
  • These studies aimed to determine how lighting might be used to improve feed intake and reduce aggressive behavior in newly weaned pigs. To examine whether this objective could be achieved an experiment was conducted to compare performance, behavior and body condition of weaners over 17-45 days, provided similar lighting quality (i.e. color temperature, color rendering index and lighting distribution) after weaning that piglets experienced prior to weaning. Triphosphor (TP) lighting to simulate daylight was provided during the day while at night, Pascal red (PR) lighting was provided to simulate the night-light piglets previously had received from infrared heating lamps. This treatment was compared to weaners provided conventional cool-white fluorescent light during the day only. Weaners on treatment lighting from 17-45 days of age showed no improvement in body weight or feed conversion at 24, 31, 38 and 45 days compared to the controls. There was, however, a significant improvement (p<0.05) in feed intake in the first week of weaning for weaners provided TP/PR lighting. Over the first 3 days of weaning, pigs on TP/PR lighting showed an increase (p<0.05) in the incidence of ear chewing but reduced (p<0.05) levels of nosing the abdomen of other pigs and reduced (p<0.05) occurrences of being stood on by other pigs. Females exhibited more (p<0.05) mounting and nosing behaviors and rubbing the heads of other pigs than males. On the other hand, males engaged in more (p<0.05) fighting, nipping, ear chewing and standing on other pigs compared to females. Pigs provided PR lighting on the first night of weaning engaged in higher (p<0.05) incidences of nosing and tail sucking behaviors, more (p<0.05) head thrusting, fighting and ear chewing compared to control pigs. The body condition of weaners provided the TP/PR lighting treatment was significantly poorer (p<0.05) compared to weaners on control lighting. In conclusion there was no improvement in production performance of weaners provided new technology lighting apart from the improvement in feed intake in the first week weaners were exposed to the TP/PR lighting.

Statistical Analysis of Low-latitude Pi2 Pulsations Observed at Bohyun Station in Korea

  • Jun, Chae-Woo;Kim, Khan-Huk;Kwon, Hyuck-Jin;Lee, Dong-Hun;Lee, Ensang;Park, Young-Deuk;Hwang, Junga
    • Journal of Astronomy and Space Sciences
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    • v.30 no.1
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    • pp.25-32
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    • 2013
  • We statistically investigated the properties of low-latitude Pi2 pulsations using Bohyun (BOH, Mlat = $29.8^{\circ}$, L = 1.35) ground magnetometer data in 2008. For this 1-year interval, 582 Pi2 events were identified when BOH was in the nightside from 1800 to 0600 local times. We found the following Pi2 characteristics. (1) The occurrence distribution of Pi2s is relatively constant in local times. (2) The Pi2 frequency varies in local times. That is, Pi2 pulsations in postmidnight sector had higher frequency than in premidnight sector. (3) Pi2 power in premidnight sector is stronger than in postmidnight sector. (4) Pi2 frequency has positive correlation with solar wind speed and AE index. (5) Pi2 power has not a clear correlation with solar wind parameters. This indicates that Pi2 power is not controlled by external sources. (6) It is found that the most probable-time between Pi2 onsets is ${\Delta}t$ ~ 37.5 min: This is interpreted to be the period between Pi2 pulsations when they occur cyclically. We suggest that ${\Delta}t$ ~ 37.5 min is the occurrence rate of reconnection of open field lines in the tail lobe.

Suboptimal Decision Fusion in Wireless Sensor Networks under Non-Gaussian Noise Channels (비가우시안 잡음 채널을 갖는 무선 센서 네트워크의 준 최적화 결정 융합에 관한 연구)

  • Park, Jin-Tae;Koo, In-Soo;Kim, Ki-Seon
    • Journal of Internet Computing and Services
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    • v.8 no.4
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    • pp.1-9
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    • 2007
  • Decision fusion in wireless sensor networks under non-Gaussian noise channels is studied. To consider the tail behavior noise distributions, we use a exponentially-tailed distribution as a wide class of noise distributions. Based on a canonical parallel fusion model with fading and noise channels, the likelihood ratio(LR) based fusion rule is considered as an optimal fusion rule under Neyman-Pearson criterion. With both high and low signal-to-noise ratio (SNR) approximation to the optimal rule, we obtain several suboptimal fusion rules. and we propose a simple fusion rule that provides robust detection performance with a minimum prior information, Performance evaluation for several fusion rules is peformed through simulation. Simulation results show the robustness of the Proposed simple fusion rule.

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Spermatozoal Ultrastructure and Phylogenetic Relationships of the Subfamily Gobioninae (Cyprinidae, Teleostei) 1. Ultrastructure of the Spermatozoa of the Korean Slender Gudgeon Squalidus gracilis majimae (한국산 모샘치아과(잉어과, 경골어강) 어류 정자의 미세구조와 계통학적 연구 1. 긴몰개 Squalidus gracilis majimae 정자의 미세구조)

  • Lee, Young-Hwan;Kim, Kgu-Hwan
    • Applied Microscopy
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    • v.28 no.1
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    • pp.63-71
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    • 1998
  • The spermatozoon of Squalidus gracilis majimae is approximately $36.6{\mu}m$ in length and is characterized by a spherical nucleils with the clear chromatin, a short midpiece containing the mitochondria, and a flagellum positioned tangentially to the nucleus. An acrosome is absent as in all teleost fishes. The nucleus is about $1.9{\mu}m$ in diameter and in its periphery contains the electron-lucent chromatin distinguished from the electron-dense chromatin occupying most of the nucleus. The shallow nuclear fossa contains the proximal centriole, instead of two centrioles in deep nuclear fossa in siluroids. The proximal and distal centrioles are oriented approximately $140^{\circ}$ to each other. The mitochondria of 10 or more in number are arranged in three layers and do not surround the axoneme. The asymmetrical distribution of the mitochondria and the eccentrical position of the nucleus with regard to the tail are the general pattern of the cyprinid spermatozoa. S. gracilis majimae spermatozoa have the most mitochondria and the deepest cytoplasmic canal among cyprinid species. The flagellum lacks the lateral fins.

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Effects of Annealing Temperature on the Local Current Conduction of Ferromagnetic Tunnel Junction (열처리에 따른 강자성 터널링 접합의 국소전도특성)

  • Yoon, Tae-Sick;Tsunoda, Masakiyo;Takahashi, Migaku;Li, Ying;Park, Bum-Chan;Kim, Cheol-Gi;Kim, Chong-Oh
    • Korean Journal of Materials Research
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    • v.13 no.4
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    • pp.233-238
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    • 2003
  • Ferromagnetic tunnel junctions, Ta/Cu/Ta/NiFe/Cu/$Mn_{75}$ $Ir_{25}$ $Co_{70}$ $Fe_{30}$/Al-oxide, were fabricated by do magnetron sputtering and plasma oxidation process. The effect of annealing temperature on the local transport properties of the ferromagnetic tunnel junctions was studied using contact-mode Atomic Force Microscopy (AFM). The current images reflected the distribution of the barrier height determined by local I-V analysis. The contrast of the current image became more homogeneous and smooth after annealing at $280^{\circ}C$. And the average barrier height $\phi_{ave}$ increased and its standard deviation $\sigma_{\phi}$ X decreased. For the cases of the annealing temperature more than $300^{\circ}C$, the contrast of the current image became large again. And the average barrier height $\phi_{ave}$ decreased and its standard deviation $\sigma_{\phi}$ increased. Also, the current histogram had a long tail in the high current region and became asymmetric. This result means the generation of the leakage current that is resulted from the local generation of a low barrier height region. In order to obtain the high tunnel magnetoresistance(TMR) ratio, the increase of the average barrier height and the decrease of the barrier height fluctuation must be strictly controlled.led.

Improving the Perfectionism Index to Identify Influential Journals versus Mass Producers (완벽주의 지수 PI의 개량을 통한 유력 학술지와 대량생산 학술지의 구분)

  • Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.36 no.2
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    • pp.201-222
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    • 2019
  • The Perfectionism Index (PI) is an indicator that is recently proposed to distinguish influential researchers from mass producers. In this study, Near Perfectionism Index (NPI), an improved indicator of Perfectionism Index, can be a solution to the problem of PI that indiscriminately gives a penalty to all low-cited papers regardless of publishing time or other issues. NPI improved the method to give a penalty to tail complement area considering the citation distribution curve. It prevents the improvement of the h-index from adversely affecting the researcher's influence indicator. This study uses NPI to evaluate information and library science journals in Web of Science database. It successfully distinguishes between influential journals and mass producers unlike journal h-index or average citation frequency which could not differentiate influentials from mass producers.