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Retrieval of Atmospheric Optical Thickness from Digital Images of the Moon (월면 디지털 영상 분석을 이용한 대기 광학두께 산출)

  • Jeong, Myeong-Jae
    • Korean Journal of Remote Sensing
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    • v.29 no.5
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    • pp.555-568
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    • 2013
  • Atmospheric optical thickness during nighttime was estimated in this study using analysis on the images of the moon taken from commercial digital camera. Basically the Langely Regression method was applied to the observations of the moon for the cloudless and optically stable sky conditions. The spectral response functions for the red(R), green(G), and blue(B) channels were employed to derive effective wavelength centers of each channel for the observations of the moon, and the correspondent Rayleigh optical thickness were also calculated. Aerosol optical thickness (AOT) was calculated by subtracting Rayleigh optical thickness from the atmospheric optical thickness derived from the Langley regression method. As there are only handful of nighttime AOT observations, the AOT from the moon observations was compared with the AOT from sun-photometers and the MODIS satellite sensor, which was taken several hours before the moon observations of this study. As a result, the values of AOT from moon observations agree with those from sun-photometers and MODIS within 0.1 for the R, G, B channels of the digital camera. On the other hand, ${\AA}$ngstr$\ddot{o}$m Exponent seems to be subject to larger errors due to its sensitiveness to the spectral errors of AOT. Nevertheless, the results of this study indicate that the method reported in this study is promising as it can provide nighttime AOT relatively easily with a low cost instrument like digital camera. More observations and analyses are warranted to attain improved nighttime AOT observations in the future.

Actions of acetylcholine, norepinephrine, histamine and prostaglandin F2α on motility of pig oviductal isthmic smooth muscle (돼지 난관협부 평활근의 운동성에 대한 acetylcholine, norepinephrine, histamine 및 prostaglandin F2α의 작용)

  • Rho, Gyu-jin;Park, Sang-eun;Shim, Cheol-soo;Kim, Joo-heon;Choe, Sang-young
    • Korean Journal of Veterinary Research
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    • v.34 no.3
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    • pp.493-500
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    • 1994
  • The purpose of this study was to investigate the effects of neurotransmitters and the source of $Ca^{2+}$ in the effects of neurotransmitters on the motility of pig oviductal isthmic smooth muscle. The motility of the isolated smooth muscle was recorded by using physiological recording system. The results were summarized as follows; Acetylcholine, norepinephrine, histamine and prostaglandin $F_{2{\alpha}}(PGF_{2{\alpha}})$ caused the contraction and the contractile responses were increased in a dose-dependent manner from the concentration of $10^{-7}$ to $10^{-4}M$. The maximum contractility of acetylcholine, norepinephrine, histamine and $PGF_{2{\alpha}}$ was 65.99, 28.66, 83.99 and 47.33% of 100 mM K contraction, respectively. The contractile response induced by acetylcholine$(10^{-6}M)$ was completely blocked by the pretreatment with cholinergic receptor blocker, atropine$(10^{-6}M)$, the contractile response induced by norepinephrine$(10^{-5}M)$ was blocked by the pretreatment with ${\alpha}$-adrenergic receptor blocker, phentolamine$(10^{-6}M)$ but was not blocked and rather increased by the pretreatment with ${\beta}$-adrenergic receptor blocker. propranolol$(10^{-6}M)$, the contractile response induced by histamine$(10^{-6}M)$ was completely blocked by the pretreatment with $H_1$-histaminergic receptor blocker, pyrilamine$(10^{-6}M)$ but was increased by the pretreatment with $H_2$-histaminergic receptor blocker, cimetidine$(10^{-6}M)$. The contractile response induced by acetylcholine$(10^{-6}M)$, norepinephrine$(10^{-5}M)$ and histamine$(10^{-6}M)$ was weakly contracted response in $Ca^{2+}$-free medium, but the contractile response induced by $PGF_{2{\alpha}}(10^{-6}M)$ was disappeared. The contractile response induced by acetylcholine$(10^{-6}M)$, norepinephrine$(10^{-5}M)$ and histamine$(10^{-6}M)$ was powerfully depressed by the pretreatment with $Ca^{2+}$-channel blocker, verapamil$(10^{-5}M)$ but the contractile response induced by $PGF_{2{\alpha}}(10^{-6}M)$ was completely inhibited.

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Multiscale Modeling and Simulation of Direct Methanol Fuel Cell (직접메탄올 연료전지의 Multiscale 모델링 및 전산모사)

  • Kim, Min-Su;Lee, Young-Hee;Kim, Jung-Hwan;Kim, Hong-Sung;Lim, Tae-Hoon;Moon, Il
    • Membrane Journal
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    • v.20 no.1
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    • pp.29-39
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    • 2010
  • This study focuses on the modeling of DMFC to predict the characteristics and to improve its performance. This modeling requires deep understanding of the design and operating parameters that influence on the cell potential. Furthermore, the knowledge with reference to electrochemistry, transport phenomena and fluid dynamics should be employed for the duration of mathematical description of the given process. Considering the fact that MEA is the nucleus of DMFC, special attention was made to the development of mathematical model of MEA. Multiscale modeling is comprised of process modeling as well as a computational fluid dynamics (CFD) modeling. The CFD packages and process simulation tools are used in simulating the steady-state process. The process simulation tool calculates theelectrochemical kinetics as well as the change of fractions, and at the same time, CFD calculates various balance equations. The integrated simulation with multiscal modeling explains experimental observations of transparent DMFC.

Understanding on MR Perfusion Imaging Using First Pass Technique in Moyamoya Diseases (Moyamoya 질환에서 1차 통과기법을 이용한 자기공명관류영상의 이해)

  • Ryu, Young-Hwan;Goo, Eun-Hoe;Jung, Jae-Eun;Dong, Kyung-Rae;Choi, Sung-Hyun;Lee, Jae-Seung
    • Korean Journal of Digital Imaging in Medicine
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    • v.12 no.1
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    • pp.27-31
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    • 2010
  • The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.

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Performance Analysis of Intake Screens in Power Plants on Mass Impingement of Marine Organisms (발전소 취수구에 대량으로 유입하는 해양생물에 대한 스크린 설비의 성능분석)

  • Lee, Jae-Hac;Choi, Hyun-Woo;Chae, Jin-Ho;Kim, Dong-Sung;Lee, Seung-Baek
    • Ocean and Polar Research
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    • v.28 no.4
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    • pp.385-393
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    • 2006
  • Screening performance of the existing intake screens (drum and travelling screen) on mass impingement of marine animals, a euphausiid, Euphausia pacifica and a scyphozoan medusae, Aurelia aurita that have often clogged intake screens of the Uljin Nuclear Power Plant, was tested. The maximum tolerable densities of marine animals in the inflowing seawater upon the screen were estimated with two different approaches. First the maximum density of jellyfish was calculated from (1) passing amount of seawater per unit time through the screens and (2) the covered area of animals on the screens clogged. The maximum density of krill tolerable in the drum screen was cited from a simulated record of Uljin NPP, then those in the travelling screens were also calculated using the data of drum screen and ratio of seawater amount passing through the screens under the condition of 0.5m water column (W.C.) of the differential pressure (AP) produced by screens, an established permissible limit of ${\Delta}P$. Secondly, the screening performances were also tested by hydrodynamic measurements with various screen models in a circulating water channel equipped with a speed-controlling pump and a differential pressure gauge. From the first approach, the maximum tolerable densities of drum and travelling screen were calculated as 2.0 and $1.5ind/m^3$ for the Jellyfish and 900 and $680ind./m^3$ for the euphausiid, respectively. These densities estimated from the second approach were 2.1 and $0.8ind/m^3$ for the jellyfish and 1059 and $504ind/m^3$ for the euphausiid, respectively. These estimates were compared with the data from historic clogging events to evaluate the practical performance of these intake screens. The comparisons suggest a newly improved intake-screen of which performance should be at least seven times (approximately) better than the existing ones ior the krill and 3.2 times for the jellyfish, respectively, for preventing mass impingement, and for maintaining the condition of the differential pressure between the screens below 0.3 m W.C.

The South Sea Circulation of Korea: Two-dimensional Barotrophic Model (한국 남해의 해수순환: 2차원 순압모델)

  • Chang, Kyung-Il;Park, Kyeong;Suk, Moon-Sik;Kim, Choong-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.4
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    • pp.257-266
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    • 2000
  • A vertically-averaged, two-dimensional version of the Princeton Ocean Model has been applied to the South Sea to simulate the circulation driven by tides and inflows/outflows across open boundaries. To incorporate both forcing properly, a two-step modeling approach is adopted, in which the tidal circulation is first simulated by specifying the tides along the open boundaries, and then both the calculated tidal currents and the observed steady mean currents are prescribed across the open boundaries. Model results show that the steady, subtidal circulation of the South Sea is different from the residual circulation due to tidal rectification, and subtidal currents become locally as strong as tidal currents. The Cheju Current entering the model domain across the Cheju Strait flows eastward in general while shifting onshore or offshore areas following local isobaths. The Tsushima Current entering across the southern boundary reaches farther to the north in the eastern vicinity of Cheju-Do as compared to that entering across other parts of the southern boundary. The Tsushima Current turns to the east, merges with the Cheju Current, and both the Cheju and Tsushima Current exit to the East Sea through the western channel of the Korea Strait. An intensification of the outflow occurs over the deep trough adjacent to the Tsushima Island, which appears to be due to the formation of the frictional boundary layer in order to remove excess positive relative vorticity generated by an increase in the layer thickness. The circulation driven by both the tidal and inflows/outflows is different from that driven by each forcing separately in coastal areas, which implies that both forcings should be considered simultaneously in the simulation of more realistic coastal circulation.

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A study on a way to use fluorine and the recognition level by the education career periods of elementary school teachers in Jinhae region (진해지역 초등학교 교사의 교육경력에 따른 불소이용법의 효과 및 지식도 조사연구)

  • Park, Hong-Ryurn;Ku, In-Young;Moon, Seon-Jeong
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.1
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    • pp.59-68
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    • 2011
  • Objectives : To investigate the knowledge and recognition level of fluorine by teaching career among class teachers, who are primarily responsible for oral health education, despite lack of expertise in oral health, by playing a model role for students through continuous contacts with them, and provide basic elementary data about accurate knowledge and how to correctly use fluorine remarkably effective in preventing dental caries. Methods : A self-administered survey was conducted with 539 teachers at 21 elementary schools in Jinhae City from September 1 to October 15, 2010, drawing the following conclusions. Results : 1. As for the channel for acquiring knowledge of oral health, the highest frequency was found in health programs for respondents with less than 9 years of career, in dental clinics for those with 20 to 29 years of career, and in PR booklets for those with 10 to 19 years and 30 years and longer of career. 2. Use of fluorine-containing toothpaste and fluorine spread is very effective and effective in preventing dental caries got 64.9%, 72.2%, 72.3%, 77.7% and 54.0%, 63.1%, 62.2%, 69.7%, respectively, among elementary school teachers with less than 9 years, 10 to 19 years, 20 to 29 years, and 30 years and longer of career. 3. Intake of fluoride and toothbrushing with fluoric solution is very effective and effective in preventing dental caries got 33.3%, 40.1%, 39.5%, 55.3% and 50.0%, 54.9%, 48.8%, 69.7%, respectively, among elementary school teachers with less than 9 years, 10 to 19 years, 20 to 29 years, and 30 years and longer of career. 4. Use of fluoric tablets is very effective and effective in preventing dental caries got 32.9%, 36.0%, 36.1%, 47.3%, respectively, among elementary school teachers with less than 9 years, 10 to 19 years, 20 to 29 years, and 30 years and longer of career. 5. Most of the elementary school teachers knew the fact that fluorine increases dental resistance to cavity and prevents bacterial growth but gave incorrect responses to properties of becoming basic nutrients or inducing recalcification. Conclusions : Various types of application of fluorine during the elementary-level childhood experiencing the most frequent dental caries will be very useful in improving oral health in the future. It is necessary to enable class teachers to get correct recognition of fluorine through supplementary and job training based on technical knowledge and various educational materials so that they, who are directly responsible for health management through continuous contacts with students, can understand how to correctly use fluorine and get accurate knowledge.

A study on the application of redundancy in information design (정보디자인의 잉여성적용 연구)

  • Oh, Byung-Keun;Hong, Suk-Il
    • Archives of design research
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    • v.18 no.1 s.59
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    • pp.49-58
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    • 2005
  • Focusing on the information sender, message, channel, and receiver, the existing information theory deals with the noise, information contents, and probability of choice, which involve in the process of information transmission. In the current digital environment, besides simply conveying information itself through media, the important issue is how to efficiently convey information. Therefore, we need to analyze the theory in different perspective, and to research the Information redundancy for the methodology of information design. The redundancy causes the receiver to have attraction to the information and to reduce its contents due to its supplement and repetition. So it can play a role of efficient communication method. The concept of redundancy is applied to the communication of art such as literature, architecture, painting, and design to accomplish efficient communication. In order to get persuasive information design for the receiver's perspective we need to make use of this concept. The redundancy can be applied with the technical aspect of multimedia and Interaction, which add supplemental expression, or sort of event for the receiver's experience and memory. In the process of constructing information it can be applied with the structure of gaming redundancy, entropy, the accumulating communication code using entertaining feature, and storytelling methodology. The noise and entropy could be used for the means of making redundancy, not the obstacle to information. The redundancy gives the receiver attraction on the information and makes them have strong will of interpreting it so that the purpose of conveying information will be accomplished efficiently.

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Separation and growth monitoring of oyster mushroom spores using gravitational field-flow fractionation (GrFFF) (중력 장-흐름 분획법을 이용한 느타리버섯 포자의 분리 및 성장 모니터링)

  • Kim, Sun Tae;Ji, Eun Young;Lee, Jae Chan;Lee, Seungho
    • Analytical Science and Technology
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    • v.26 no.4
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    • pp.262-267
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    • 2013
  • Gravitational field-flow fractionation (GrFFF) is a separation technique that utilizes earth's gravity as the external field. GrFFF is a convenient tool for the size and/or density-based separation of micron-sized particles of various origins. In this study, GrFFF was employed for size-based separation of oyster mushroom spores. Oyster mushroom spores have smooth surface and are of cylindrical to narrow kidney-shapes with 5 to 12 im in longer dimension and 3 to 4 im in shorter dimension, as was confirmed by optical microscope (OM). GrFFF conditions were optimized for separation and characterization of spores by varying the channel flow rate from 0.5 to 1 mL/min. During the GrFFF elution of the spores, 3 fractions were collected to confirm the growth of oyster mushroom spore. The collected fractions were incubated for 30 days in water to examine the influence of the size on the growth of the spores. Results suggested that the oyster mushroom spores collected at the middle part of the GrFFF fractogram grew faster than those collected at the beginning or at the end of the fractogram.

Depositional Environments of the Continental Shelf Sediments between Geoje and Namhae Islands (거제-남해간 해저퇴적물의 퇴적환경에 관한 연구)

  • KIM Dae-Choul;SONG Si-Tae;YOO Byeong-Jo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.2
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    • pp.166-174
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    • 1987
  • Distribution, bathymetry and textural parameters of the bottom sediment deposited between Geoje and Namhae Islands were studied to understand the depositional environment of the area. The study area is divided into three different provinces. Except for the Gwangyang Bay and Changseon Channel, mud dominates in the western part whereas sandy mud and muddy sand prevail in the southeastern part including the eastern area of the Yogji Island. The relict sediment is located in the eastern part of the area. Generally, the Holocene sediment, located in the northern part of the area, is considered to be transported and deposited by a pelagic suspension mode. Influence of strong tidal currents results in some depressions in the vicinity of Changseon Island and the eastern part of the Yogji Island, The Tsushima Warm Current is supposed to affect the southern part of the area. The two parallels sand ridges lying in the southeastern part of the area are covered with very thin Holocene mud. This seems to be caused by the winnowing effect of the current. The similarity between the two directions of the current and the ridges encourages this idea. The boundary between the Holocene and relict sediment, however, lies further south the ridges.

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