• Title/Summary/Keyword: Spikes

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Major Characteristics of Hordeum bulbosum and Haploid Production of Cultivated Barley by Pollinating with H. bulbosum L. (야생보리(Hordeum bulbosum)의 주요 특성 및 이를 이용한 보리 반수체육성)

  • 정동희;민경수;천종은
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.6
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    • pp.531-536
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    • 1993
  • Bulbosum method, which haploids are developed by pollinating with H. bulbosum have been productive to be recommended as an effective method for the production of genetically stable normal barley hybrids. The purpose of this study is to investigate several characters of H. bulbosum, seed set and embryo development rate pollinated with H. bulbosum in order to establish a method for improvement of embryo development and to find conditions favoring plant development from the embryos cultured in vitro. Three lines of H. bulbosum used as pollinators: GBC(2${\times}$), Spenish diploid(2${\times}$) and var. Jaaska (4${\times}$) were morphologically similar, having characteristically narrow leaves, narrow and long culms, long spikes and anthesis duration in comparison with H. vulgare. H. bulbosum, var. Jaaska(4${\times}$) on being pollinated to barley cultivars, increased embryo formation by 8% and plant development in vitro by three times compared to the other diploid lines. the plants developed were not normal barley hybrids but had some H. bulbosum chromosomes uneliminated, indicating that the line was unstable as a pollinator to induce barley haploids.

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An Assessment of the Deterioration of Fabricated Metal Thread with Light, and Temperature and Humidity Factors: A Focused Study of Asian Textile Collections at the Metropolitan Museum of Art, New York

  • Park, Hae Jin;Hwang, Minsun;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.34 no.4
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    • pp.245-257
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    • 2018
  • To investigate the deterioration of textiles with metal thread, I surveyed 40 textile objects, dating from the 11th to the 19th century from Korea, China, Japan, and Central Asia at the Metropolitan Museum of Art, New York. This survey included various types, widths, and thicknesses of metal thread. In addition, deterioration was examined under the microscope and color information was collected using the spectrophotometer. While investigating metal thread in the collections, I fabricated 12 different types of metal samples with metal leaf(24K gold, silver, and copper leaf), adhesive (hide animal glue and a mixture of hide animal glue and iron oxide red), and paper substrate(Korean mulberry and Taiwanese kozo paper). The accelerated deterioration process of those fabricated samples was carried out using a light box(UV and daylight), and a humidity cabinet. In the light experiment with blue scales textile fading card(aka, blue wool standard), the metal leaf began to peel off during the deterioration process with 756,000 lux-hours UV and daylight. In the temperature and humidity experiment, I could observe the reddish tarnish on copper, and some part of it began to peel off. Color reading on the light exposed samples showed that the degree of color change on the surface follows the amount of exposure as it increased over time. On the other hand, color change on the samples after artificial deterioration using temperature and humidity factors showed random change of color with occasional spikes. Distortion of original shape worsened in the samples exposed to temperature and humidity.

Simple Digital LCD Backlight Inverter using a Single-chip Microcontroller (단일칩 마이크로컨트롤러를 이용한 간단한 디지털 LCD 백라이트 인버터)

  • Jeong, Gang-Youl
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.2
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    • pp.461-468
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    • 2010
  • This paper presents a simple digital LCD backlight inverter using a single-chip microcontroller. The proposed inverter reduces the ignition voltage and eliminates the current spikes and hence improves the ignition behavior of the cold cathode fluorescent lamp(CCFL). Thus it increases the CCFL's life span. This is achieved by implementing a digital dimming control algorithm, that contains the soft-starting algorithm, all on a single-chip microcontroller. The inverter utilizes the full-bridge resonant circuit topology. The design example along with a simple analysis for the inverter is shown, and the experimental results of the designed prototype results in close agreement with the theoretical analysis and explanation. The overall system's power efficiency is approximately 85%. Compared with conventional inverters, the ignition voltage is reduced by around 30% without any lamp current spike occurring during the dimming control operation.

Development of Diagnosis Protocol for Micro-spike Biopsy Using Paraffin-based Tissue Collecting tool (파라핀 기반의 조직회수도구를 사용한 채취 조직의 진단 프로토콜 개발)

  • Jeong, Hyo-Young;Koo, Kyo-In;Lee, Sang-Min;Park, Ho-Soo;Hong, Suk-Jun;Bang, Seoung-Min;Song, Si-Young;Cho, Dong-Il
    • Journal of Biomedical Engineering Research
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    • v.31 no.3
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    • pp.234-239
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    • 2010
  • We have developed and reported several micro-spikes for minimally invasive biopsy. This paper presents a diagnosis protocol for micro-spike biopsy using paraffin-based tissue collecting tool. Using the proposed tissue collecting tool, which has a negative micro-spike structure in a porous chamber, the biopsied tissue in a micro-spike is effectively detached. The proposed diagnosis protocol prevents the loss of tissues in a paraffin embedding and sectioning process. Hence, it is compatible with conventional histopathology without additional reagents and processes. The gastro-intestinal tissue of a pig is biopsied in an in vivo environment, and then it is detached from a micro-spike using the paraffin-based tissue collecting tool. A histopathological photomicrograph of the detached tissue is acquired with the proposed diagnosis protocol. The acquired image offers clinical quality. This result shows that the paraffin-based tissue collecting tool is applicable to the medical practice.

Change of Sludge Consortium in Response to Sequential Adaptation to Benzene, Toluene, and o-Xylene

  • Park, Jae-Yeon;Sang, Byoung-In
    • Journal of Microbiology and Biotechnology
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    • v.17 no.11
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    • pp.1772-1781
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    • 2007
  • Activated sludge was sequentially adapted to benzene, toluene, and o-xylene (BTX) to study the effects on the change of microbial community. Sludge adapted to BTX separately degraded each by various rates in the following order; toluene>o-xylene>benzene. Degradation rates were increased after exposure to repeated spikes of substrates. Eleven different kinds of sludge were prepared by the combination of BTX sequential adaptations. Clustering analyses (Jaccard, Dice, Pearson, and cosine product coefficient and dimensional analysis of MDS and PCA for DGGE patterns) revealed that acclimated sludge had different features from nonacclimated sludge and could be grouped together according to their prior treatment. Benzene- and xylene-adapted sludge communities showed similar profiles. The sludge profile was affected from the point of the final adaptation substrate regardless of the adaptation sequence followed. In the sludge adapted to 50 ppm toluene, Nitrosomonas sp. and bacterium were dominant, but these bands were not dominant in benzene and benzene after toluene adaptations. Instead, Flexibacter sp. was dominant in these cultures. Dechloromonas sp. was dominant in the culture adapted to 50 ppm benzene. Thauera sp. was the main band in the sludge adapted to 50 ppm xylene, but became vaguer as the xylene concentration was increased. Rather, Flexibacter sp. dominated in the sludge adapted to 100 ppm xylene, although not in the culture adapted to 250 ppm xylene. Two bacterial species dominated in the sludge adapted to 250 ppm xylene, and they also existed in the sludge adapted to 250 ppm xylene after toluene and benzene.

Neurotensin Enhances Gastric Motility in Antral Circular Muscle Strip of Guinea-pig

  • Koh, Tae-Yong;Kim, Sung-Joon;Lee, Sang-Jin;Kang, Tong-Mook;Jun, Jae-Yeoul;Sim, Jae-Hoon;So, In-Suk;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.227-234
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    • 2000
  • Many reports suggest that neurotensin (NT) in the gastrointestinal tract may play a possible role as a neurotransmitter, a circulating hormone, or a modulator of motor activity. NT exerts various actions in the intestine; it produces contractile and relaxant responses in intestinal smooth muscle. This study was designed to investigate the effect of NT on motility of antral circular muscle strips in guinea-pig stomach. To assess the role of $Ca^{2+}$ influx in underlying mechanism, slow waves were simultaneously recorded with spontaneous contractions using conventional intracellular microelectrode technique. At the concentration of $10^{-7}$ M, where NT showed maximum response, NT enhanced the magnitude $(863{\pm}198%,\;mean\;SEM,\;n=13)$ and the frequency $(154{\pm}10.3%,\;n=11)$ of spontaneous contractions. NT evoked a slight hyperpolarization of membrane potential, tall and steep slow waves with abortive spikes $(278{\pm}50%,\;n=4).$ These effects were not affected by atropine $(2\;{\mu}M),$ guanethidine $(2\;{\mu}M)$ and tetrodotoxin (0.2μM). NT-induced contractile responses were abolished in $Ca^{2+}-free$ solution and reduced greatly to near abolition by $10\;{\mu}M$ of verapamil or 0.2 mM of $CdCl_2.$ Verapamil attenuated the effects of NT on frequency and amplitude of the slow waves. Taken together, these results indicate that NT enhances contractility in guinea-pig gastric antral circular muscle and $Ca^{2+}$ influx through the voltage-operated $Ca^{2+}$ channel appears to play an important role in the NT-induced contractile mechanism.

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Burnup Measurement of Irradiated Uranium Dioxide Fuel by Chemical Methods (화학적 방법에 의한 핵연료의 연소도 측정)

  • Kim, Jung-Suk;Han, Sun-Ho;Suh, Moo-Yul;Joe, Kih-Soo;Eom, Tae-Yoon
    • Nuclear Engineering and Technology
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    • v.21 no.4
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    • pp.277-286
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    • 1989
  • Destructive methods are used for the turnup determination of an irradiated PWR fuel. One of the methods includes U, Pu, Nd-148 and Nd-(145+146) determination by an isotope dilution mass spectrometry using triple spikes (U-233, Pu-242 and Nd-150). The method involves two sequential ion exchange resin separation procedures. Pu is eluted from the first anion exchange resin column (Dowex AG 1$\times$8) with 12 M HCl-0.1 M HI mixed solution, followed by U elution with 0.1 M HCl. Nd is isolated from other fission products on the second anion exchange resin column (Dowex AG 1$\times$4) with a nitric acid-methanol eluent. Each fraction is analysed by thermal ionization mass spectrometry. The difference between Nd-148 and Nd-(145+146) method is found with an average 2.07%. The results are compared with those by the heavy element method using U and Pu isotopes and by the destructive y-spectrometric measurement of Cs-137. The dependences of isotope composition of U and Pu on burn-up, and correlation between those isotopes are illustrated graphically.

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The Effects of a Er:YAG Laser on Machined, Sand-Blasted and Acid-Etched, and Resorbable Blast Media Titanium Surfaces Using Confocal Microscopy and Scanning Electron Microscopy

  • Park, Jun-Beom;Kim, Do-Young;Ko, Youngkyung
    • Journal of Korean Dental Science
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    • v.9 no.1
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    • pp.19-27
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    • 2016
  • Purpose: Laser treatment has become a popular method in implant dentistry, and lasers have been used for the decontamination of implant surfaces when treating peri-implantitis. This study was performed to evaluate the effects of an Erbium-doped:Yttrium-Aluminum-Garnet (Er:YAG) laser with different settings on machined (MA), sand-blasted and acid-etched (SA), and resorbable blast media (RBM) titanium surfaces using scanning electron microscopy and confocal microscopy. Materials and Methods: Four MA, four SA, and four RBM discs were either irradiated at 40 mJ/20 Hz, 90 mJ/20 Hz, or 40 mJ/25 Hz for 2 minutes. The specimens were evaluated with scanning electron microscopy and confocal microscopy. Result: The untreated MA surface demonstrated uniform roughness with circumferential machining marks, and depressions were observed after laser treatment. The untreated SA surface demonstrated a rough surface with sharp spikes and deep pits, and the laser produced noticeable changes on the SA titanium surfaces with melting and fusion. The untreated RBM surface demonstrated a rough surface with irregular indentation, and treatment with the laser produced changes on the RBM titanium surfaces. The Er:YAG laser produced significant changes on the roughness parameters, including arithmetic mean height of the surface (Sa) and maximum height of the surface (Sz), of the MA and SA surfaces. However, the Er:YAG laser did not produce notable changes on the roughness parameters, such as Sa and Sz, of the RBM surfaces. Conclusion: This study evaluated the effects of an Er:YAG laser on MA, SA, and RBM titanium discs using confocal microscopy and scanning electron microscopy. Treatment with the laser produced significant changes in the roughness of MA and SA surfaces, but the roughness parameters of the RBM discs were not significantly changed. Further research is needed to evaluate the efficiency of the Er:YAG laser in removing the contaminants, adhering bacteria, and the effects of treatment on cellular attachment, proliferation, and differentiation.

A Study on the Pixel-Parallel Usage Processing Using the Format Converter (포맷 변환기를 이용한 화소-병렬 화상처리에 관한 연구)

  • Kim, Hyeon-Gi;Lee, Cheon-Hui
    • The KIPS Transactions:PartA
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    • v.9A no.2
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    • pp.259-266
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    • 2002
  • In this paper we implemented various image processing filtering using the format converter. This design method is based on realized the large processor-per-pixel array by integrated circuit technology. These two types of integrated structure are can be classify associative parallel processor and parallel process DRAM (or SRAM) cell. Layout pitch of one-bit-wide logic is Identical memory cell pitch to array high density PEs in integrate structure. This format converter design has control path implementation efficiently, and can be utilize the high technology without complicated controller hardware. Sequence of array instruction are generated by host computer before process start, and instructions are saved on unit controller. Host computer is executed the pixel-parallel operation starting at saved instructions after processing start. As a result, we obtained three result that 1) simple smoothing suppresses higher spatial frequencies, reducing noise but also blurring edges, 2) a smoothing and segmentation process reduces noise while preserving sharp edges, and 3) median filtering may be applied to reduce image noise. Median filtering eliminates spikes while maintaining sharp edges and preserving monotonic variations in pixel values.

Alternative Methods for Assessments of DEMs' Erros (DEM의 오차 평가 방법에 관한 연구)

  • Hwang, Chul-Sue
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.23-34
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    • 1999
  • The most widely used measure for indicating the accuracy of DEM is RMSE(nut Mean Square Error), which is used by many national mapping agencies such as the USGS and the Ordnance Survey. Its prevalent use can be followed by the relative ease of calculation and understanding the concepts. However, there are many problems with the measure and the way from which it is often derived. First of all, the index does not involve my description of the mean donation between the two measures of elevation,. This means that it cannot interpret the distributions or patterns of errors involved in DEMs. The distribution of errors in DEMs will show some forms of spatial patterning. In order to explore the real quality of DEMs as a useful database, alternative approaches are needed. In this paper, we examined so called ESDA(Exploratory Spatial Data Analysis) approaches, which were attributed by both aspatial and spatial exploration methods. Our experimental research shows that even simple ESDA methods reveal new aspects of errors, especially spikes, striation, and terracing effect in DEMs, which my be ignored by RMSE measure.

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