• Title/Summary/Keyword: Diffusion Distance

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The Ivestigation and Estimate of Influence on Air Quality by the Exhaust of Air Pollutant from Facility of the District Heating Located in Small City (중소도시에 위치한 집단 열 공급시설에서 배출되는 대기오염물에 의한 주변 대기질의 영향 조사 및 예측)

  • Yeon, Ik-Jun;Kim, Kwang-Yul
    • Journal of environmental and Sanitary engineering
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    • v.18 no.3 s.49
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    • pp.1-10
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    • 2003
  • This study was aimed to investigate the influence on the vicinity by air pollutant generated from facility of the district heating located in local small town. We selected the seven areas arround the surroundings of facility of the district heating, compared the air quality evaluated before and after operations of the facility, and estimated the diffusion of air pollutant exhausted from the facility using a ISC model. The result was that the concentration of TSP before and after operations of the facility was 89${\sim}$94${\mu}$g/m$^3$,and 72${\sim}$81${\mu}$g/m$^3$, respectively and the latter showed a decline in concentration. Also, there was no relationship between straight distance from the facility of the district heating and the concentration of TSP. This result was applicable to cases of PM-10 and SO$_2$. We also investigated the influence on the air around the neighbored area by air pollutant produced from facility of the district heating using ISCLT3 model. The adding-concentrations of TSP, SO$_2$,NO$_2$, and CO were 0.0019${\sim}$0.00183${\mu}$g/m$^3$, 0.0029${\sim}$0.5648ppb, 0.2924${\sim}$l.9837ppb,and 0.0087${\sim}$0.0590ppb, respectively. It is predicted that each concentration is added to pollutant exhausted from facility of the district heating and is about 1/100${\sim}$1/180,000 of present air quality. This has a tiny influence on general air quality. According to this analysis, the concentration of air pollutant is less effected to pollutants expected by the facility of the district heating than other pollutants emitted from mobil source or industrial complex, and etc.

Transdermal Delivery of FITC-Ovalbumin with Microneedle System (마이크로 피부침을 이용한 FITC-OVA의 경피흡수)

  • Jang, Woo-Young;Lee, Chang-Rae;Seo, Seong-Mi;Lee, Bong;Kim, Moon-Suk;Khang, Gil-Son;Lee, Han-Gu;Lee, Hai-Bang
    • Journal of Pharmaceutical Investigation
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    • v.35 no.6
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    • pp.403-409
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    • 2005
  • For transdermal delivery of large molecular drugs such as vaccine and protein drugs, novel microneedle treatment device with roll was designed. The roll dimension is 1.43 cm diameter and 2.8 cm perimeter. Total number of microneedle on the roll is 3,360 with $230\;{\mu}m$ height and $740\;{\mu}m$ distance. The pore with $150\;{\mu}m$ depth and $35\;{\mu}m$ diameter on the skin was made by the designed microneedle device. This system could be achieved without pain. The permeation rates of FITC labelled ovalbumin (FITC-OVA, molecular weight: 45,000 g/mol) as a model protein were determined by modified Franz diffusion cells using skins of hairless mice or SD rats which were treated by using microneedle device two or four times. The average penetration fluxes of model protein increased from 674 to $872\;{\mu}g/cm^{2}{\cdot}hr$ as the number of treatment to make pore increased from two to four times. In conclusion, we confirmed the possibility of using the designed microneedle treatment device for transdermal delivery of the large molecular drugs.

Antimicrobial efficacy of endophytic Penicillium purpurogenum ED76 against clinical pathogens and its possible mode of action

  • Yenn, Tong Woei;Ibrahim, Darah;Chang, Lee Kok;Ab Rashid, Syarifah;Ring, Leong Chean;Nee, Tan Wen;Noor, Muhamad Izham bin Muhamad
    • Korean Journal of Microbiology
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    • v.53 no.3
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    • pp.193-199
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    • 2017
  • This study was aimed to evaluate the antimicrobial activity of Penicillium purpurogenum ED76 on several clinically important microorganisms. The endophytic fungus P. purpurogenum ED76 was previously isolated from Swietenia macrophylla leaf. The antimicrobial efficacy of P. purpurogenum ED76 dichloromethane extract was determined via disc diffusion and broth microdilution assay. A kill curve study was conducted and the morphology of extract treated bacterial cells were viewed under scanning electron microscope. The dichloromethane extract showed significant inhibitory activity on 4 test bacteria and 2 test yeasts. The minimal inhibitory concentration of the extract ranged from 125 to $1,000{\mu}g/ml$, which indicates the different susceptibility levels of the test microorganisms to the fungal extract. The kill curve study has revealed a concentration-dependent inhibition for all test microorganisms. With the increase of the extract concentration, the microbial growth was significantly reduced. The scanning electron micrograph of dichloromethane extract-treated Staphylococcus aureus cells showed the total damage of the cells. The cell wall invagination of the bacterial cells also indicates the loss of cellular materials and metabolic activity. The gas chromatography mass spectrometry analysis of the extract also showed that the major compound was stigmasterol, which constitutes 45.30% of the total area. The dichloromethane extract of P. purpurogenum ED76 exhibited significant inhibitory activity on several clinically important bacteria and yeasts. The study proposed a possible mode of action that the extract cause significant damage to the morphology of S. aureus cells.

The Effects of Korean Wave on Korea's Exportation (한류가 우리나라 수출에 미치는 효과)

  • Choi, Mun-Seong
    • International Commerce and Information Review
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    • v.14 no.1
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    • pp.67-86
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    • 2012
  • In this paper, we explore the effects of Korean Wave (Hanryu) on the Korea's export by using the gravity model in which we use independent variables such as real GDP, population, distance between the two nation, and Korean Wave. Among these, the Korean Wave can be classified into 5 categories according to the progress stage of Korean Wave which was analysed by KOTRA(2011). The data set has covered 67 countries in 2010. The results show that the Korean Wave has the positive impact on Korea's export. Also, that impact is getting bigger to the Korea exportation as the stage of Korean Wave spreads to the world. These results implies that the Korean Wave plays an important role to promote the Korea's exportation. Therefore, the Koreans should do their best to continuously expand the Korean Wave for the purpose of increasing Korea exportation.

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Research and Implementation of Using RF wireless Power Transmission System for Wireless Sensor Nodes Battery-Charging Power Harvesting Module (RF 무선전력전송을 이용한 센서노드 배터리 충전용 전력획득모듈 연구 및 구현)

  • Jung, Won-Jae;Park, Jun-Seok
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.6
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    • pp.34-42
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    • 2011
  • With the progress of USN technology, fields to which wireless sensor node is applicable are increased under a condition that it holds a lot of problems to solve for betterment. One of the problems which acts as an obstacle to USN industry diffusion is the wireless sensor node battery exchange to their individual life cycle. Exchanging the battery of so many sensor nodes one by one requires a great deal of times and costs. Such problem is against the convenience supply -aim by applying USN technology. In this paper, using RF wireless power transmission system that power transmission / harvesting module from a distance of 5 m and the power of 10 dBm with a current of 1 mA or more for Sensor Nodes in lithium-polymer battery charging system tested and verified.

Neurobiological Pathophysiology of Attention Deficit Hyperactivity Disorder (주의력결핍 과잉행동장애의 신경생물학적 병태생리)

  • Park, Hyung Bae;Joo, Yeol
    • Journal of Yeungnam Medical Science
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    • v.17 no.2
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    • pp.108-122
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    • 2000
  • Background: Models of attention deficit hyperactivity disorder(ADHD) that have proposed a hypodopaminergic state resulting in hypofunction of the prefrontal circuitry have assumed a unitary dopamine system, which largely ignores the distinct functional differences between mesocortical dopamine system and nigrostriatal dopamine system. Purpose: The author's goal was to develop a pathophysiological model for ADHD with greater explanotory power than dopaminergic hypofunction hypothesis in prefronal circuitry. Material and Methods: Published clinical findings on ADHD were integrated with data from genetic, pharmacological, neuroimaging studies in human and animals. Results: Molecular genetic studies suggest that three genes may increase the susceptibility to ADHD. The three candidate genes associated with ADHD are each involved in dopaminergic function, and this consistent with the neurobiologic studies implicating catecholamines in the etiology of ADHD. Pharmacological data also provide compelling support for dopamine and noradrenergic hypothesis of ADHD. Neuroimaging studies lend substantial support for the hypothesis that right-sided abnormalities of prefrontal-basal ganglia circuit would be found in ADHD. Conclusions: The present hypothesis takes advantage of the major differences between the two pertinent dopamine systems. Mesocortical dopamine system, which largely lacks inhibitory autoreceptors, is ideally positioned to regulate cortical inputs, thus improving the signal-to-noise ratio for biologically valued signals. In this circuit, therapeutic doses of stimulants are hypothesized to increase postsynaptic dopamine effects and enhance executive functions. By contrast, symptoms of hyperactivity/impulsivity in ADHD are hypothesized to be associated with relative overactivity of nigrostriatal circuit. This nigrostriatal circuit is tightly regulated by inhibitory autoreceptoors as well as by long distance feedback from the cortex, and slow diffusion of therapeutic doses of stimulant via oral administration is hypothesized to produce a net inhibition of dopaminergic neurotransmission and improves hyperactivity.

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A Study of the Diffusion and Rise of Stack Plumes at Coastal Region by Using LIDAR Observation Data

  • Yoon, Ill-Hee
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • v.26 no.1
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    • pp.43-58
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    • 1998
  • The Kwinana Shoreline Fumigation Experiment (KSFE) took place at Fremantle, WA, Australia between January 23 and February 8, 1995. The CSIRO DAR LIDAR measured plume sections from near the Kwinana Power Station (KPS) stacks to up to about 5 km downstream. It also measured boundary layer aerosols and the structure of the boundary layer on some occasions. Both stages A and C of KPS were used as tracers at different times. The heart of the LIDAR system is a Neodymium-doped Yttrium-aluminum-garnet (Nd:YAG) laser operating at a fundamental wavelength of 1064 nm, with harmonics of 532 nm and 355 nm. For these experiments the third harmonic was used because the UV wavelength at 355 nm is eye safe beyond about 50 m. The laser fires a pulse of light 6 ns in duration (about 1.8 m long) and with an energy (at the third harmonic) of about 70 mJ. This pulse subsequently scattered and absorbed by both air molecules and particles in the atmosphere. A small fraction of the laser beam is scattered back to the LIDAR, collected by a telescope and detected by a photo-multiplier tube. The intensity of the signal as a function of time is a measure of the particle concentration as a function of distance along the line of the laser shot. The smoke plume was clearly identifiable in the scans both before and after fumigation in the thermal internal boundary layer (TIBL). Both power station plumes were detected. Over the 9 days of operation, 1,568 plumes scans (214 series) were performed. Essentially all of these will provide instantaneous plume heights and widths, and there are many periods of continuous operation over several hours when it should be possible to compile hourly average plume statistics as well. The results of four days LIDAR observations of the dispersion of smoke plume in the TIBL at a coastal site are presented for the case of stages A and C.

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Chemical Composition and Antimicrobial Efficacy of Helminthostachys zeylanica against Foodborne Bacillus cereus

  • Yenn, Tong Woei;Ring, Leong Chean;Zahan, Khairul Azly;Rahman, Muhammad Sharir Abdul;Tan, Wen-Nee;Alaudin, Bintul Jauza' Shaik
    • Natural Product Sciences
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    • v.24 no.1
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    • pp.66-70
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    • 2018
  • Helminthostachys zeylanica is a rare plant grows in lightly shaded areas. The fern was traditionally used as antipyretic and antiphlogistic agents. This study was aimed to evaluate the antibacterial potential of H. zeylanica on foodborne Bacillus cereus. The chemical composition of its ethanolic extract was also determined. The plant samples were collected at Kampung Kebun Relong, Kedah, Malaysia. The ethanolic extract showed significant inhibitory activity on B. cereus with a sizeable clear zone detected on disc diffusion assay. On broth microdilution assay, the MIC of the extract on B. cereus was 6.25 mg/ml and the MBC was 12.5 mg/ml. The inhibitory activity of the extract on B. cereus was bactericidal. In the growth dynamic study, the antibacterial efficacy of the extract was concentration dependent, where a lower colony forming unit count was obtained with increased extract concentration. The SEM micrograph of extract treated B. cereus cells showed invaginations of cell wall. The bacterial cell structure collapsed after 24 h exposure to the extract. The GCMS analysis of the extract showed that the major constituents of the extract were phenol (36.26%) and quercetin (29.70%). This study is important as it shows the potential use of H. zeylanica as an effective agent to control B. cereus related infections.

Behavior of Non-buoyant Round Jet under Waves (파랑수역에서 비부력 원형 제트의 거동)

  • Ryu, Yong-Uk;Lee, Jong-In;Kim, Young-Taek
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.6
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    • pp.596-605
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    • 2007
  • The behavior of a non-buoyant turbulent round jet discharging horizontally was investigated experimentally. The instantaneous velocity field of the jet was obtained using the particle image velocimetry (PIV) method and used to calculate the mean velocity field by phase-averaging. This study tested regular waves with a relatively small wave height for a wavy environmental flow. The centerline and cross-sectional velocity profiles were reported to demonstrate the effect of the waves on the jet diffusion in respect of wave height and wave phase. The wave phase effect was studied for three phases: zero-upcrossing point, zero-downcrossing point, trough. From the results, it is found that the centerline velocity decreases and width of the cross-sectional profile increases as the wave height increases. In addition, the self-similarity of the cross-sectional profile appears to break down although the width of each case along the axial distance does not vary significantly. The phase effect is found to be relatively small compared to the wave height effect.

Path Planing for a Moving Robot using Ultra Sonic Sensors (초음파 센서를 이용한 이동로봇의 경로 계획)

  • Cha, Kyung-Hwan;Shin, Hyun-Shil;Hwang, Gi-Hyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.78-83
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    • 2007
  • Robot collects surrounding information to recognize tile unknown environment by using various sensors such as visual, infrared ray and ultra sonic sensors. Although visual sensor is the most popular one, it has some difficulties in collecting data in dark or too bright environment due to sensitivity of the light. It also requests significant amount of calculation on collecting data from certain images with marked, straight and curved ones. As an alternative, ultra sonic sensor can simply overcome this visual sensing system's flaw and easily be used. It is easier than visual system, especially in case of collecting data on object and distance in dark environment. Ultra sonic sensor can replace the expensive visual sensing system not only in avoiding obstacles but also in reaching to the target area smoothly. The purpose of this paper is to develop the algorithm to optimize the environmental recognition, path planning and free-ranging by minimizing errors caused by inaccurate information and by considering characteristics of the ultra sonic rays such as refraction and diffusion. This paper also realizes the system that can recognize the environment and make the appropriate path planning by applying the algorithm on this moving robot.

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