• Title/Summary/Keyword: Stable Region

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The Influences of Concentration Distribution and Movement of Air Pollutants by Sea Breeze and Mist around Onsan Industrial Complex (온산공업단지 주변의 박무와 해풍발생이 대기오염물질의 이동 및 농도분포에 미치는 영향)

  • Lee, Hyung-Don;Lee, Gou-Hong;Kim, In-Deuk;Kang, Ji-Soon;Oh, Kwang-Joong
    • Clean Technology
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    • v.19 no.2
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    • pp.95-104
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    • 2013
  • Onsan Industrial Complex located in a nearby the Ulsan Petrochemical Complex and in the east of the coast. For this reason, air pollution substances emitted by Onsan Industrial Complex especially tend to have an effect on meteorological factors such as sea breeze. In this study, we assessed the frequency of sea breeze and mist using the meteorological data, and analyzed potential temperature and upper wind condition for assessment of atmospheric pollution concentration influenced by meteorological phenomena in a nearby the Onsan industrial complex. From an analysis results, when mist and sea breeze happened, each higher concentration phenomenon of $PM_{10}$ and $SO_2$ appeared each 57.2%, 71.8% and 46.6%, 57.7% respectively. Hence, we confirmed that meteorological phenomena such as mist and sea breeze had an effect on high concentration of air pollution substances in the research area. Analytical result of meteorological data in upper layer using potential temperature and wind condition, we confirmed that advection of air pollution substances emitted in Ulsan Petrochemical Complex by sea breeze have an effect on high concentration in Onsan Industrial Complex and nearby the residential area. In particular;concentration in Onsan Industrial Complex were higher than the average concentration by a factor of more than over 1.5 times when sea breeze by stable condition in atmospheric layer appeared.

Geochemistry of the Heunghae, Pohang Geothermal Fields, Korea (포항 흥해지역 지열대의 지화학)

  • Yun Uk;Cho Byong-Wook
    • Journal of Soil and Groundwater Environment
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    • v.10 no.6
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    • pp.45-55
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    • 2005
  • The geothermal research has been carried out on the Heunghae, Pohang geothermal area know as having geo-heat-flow area in the Korean peninsula. This study results so far indicate that geothermal water in the area is in peripheral waters of hydrothermal area and is not in equilibrium with the reservoir rock. The average oxygen and hydrogen stable isotope values are as follows: deep groundwater $(average:\;{\delta}^{18}O=-10.1\%_{\circ},\;{\delta}D=-65.8\%_{\circ})$, intermediate groundwater (average: $(average:\;{\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ})$, shallow groundwater $(average:\;{\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ})$, surface water $(average:\;{\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ})$ respectively. Deep groundwaters was originated from a local meteoric water recharged from distant, topographically high mountain region and not affected by the sea water. High temperature zone inferred from water geothermometers is around D-1, D-5, D-6, 1-04 well zones. The estimated enthalpy from Silica-enthalpy mixing model is near 410 kJ/kg, which corresponds to the temperature of $98^{\circ}C$, and in consistent with the result of Na-K and K-Mg geothermometer.

Several Factors Affecting Transformation Efficiency of tall Fescue (톨페스큐의 효율적인 형질전환을 위한 몇 가지 요인의 영향)

  • 김진수;이상훈;이병현
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.3
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    • pp.237-242
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    • 2004
  • A system for the production of transgenic plants has been developed for tall fescue (Festuca arundinacea Schreb.) via Agrobacterium-mediated transformation of mature seed-derived embryogenic callus. Seed-derived calli were infected and co-cultured with Agrobacterium EHA101 carrying standard binary vector pIG121Hm encoding the hygromycin phosphotransferase (HPT), neomycin phosphotransferase II (NPTII) and intron-containing $\beta$-glucuronidase (intron-GUS) genes in the T-DNA region. The effects of several factors on transformation and the expression of the GUS gene were investigated. Inclusion of $200\mu\textrm{M}$ acetosyringone (AS) in inoculation and co-culture media lead to a increase in stable transformation efficiency. Transformation efficiency was increased when embryogenic calli were co-cultured for 5 days on the co-culture medium. The highest transformation efficiency was obtained when embryogenic calli were inoculated with Agyobacterium in the presence of 0.1% Tween20 and $200\mu\textrm{M}$ AS. Hygromycin resistant calli were developed into complete plants via somatic embryogenesis. GUS histochemical assay and Southern blot analysis of transgenic plants demonstrated that transgenes were successfully integrated into the genome of tall fescue.

Effect of Acetosyringone and Variety on Transformation of Orchardgrass (오차드그래스의 형질전환에 있어서 Acetosyringone과 품종이 미치는 영향)

  • Lee, Ki-Won;Lee, Sang-Hoon;Lee, Dong-Gi;Kim, Do-Hyun;Lee, Byung-Hyun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.26 no.4
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    • pp.193-198
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    • 2006
  • Effects of acetosyringone and on Agrobacterium-mediated transformation of orchardgrass were investigated. Embryogenic calli induced from 3 varieties, Frontier, Potomac and Roughrider, were infected and co-cultured with Agrobacterium EHA101 carrying standard binary vector pIG121Hm encoding the hygromycin phosphotransferase(HPT), neomycin phosphotransferase II(NPTII) and intron-containing ${\beta}-glucuronidase$ (intron-GUS) genes in the T-DNA region. The effects of varieties and acetosyringone(AS) concentrations on transformation and the expression of the GUS gene were investigated. Inclusion of $200{\mu}M$ AS in inoculation and co-cultivation media lead to a significant increase in stable transformation efficiency. Hygromycin resistant calli were developed into complete plants via somatic embryogenesis. GUS histochemical assay and PCR analysis of transgenic plants demonstrated that transgenes were integrated into the genome of orchardgrass.

Radiation Effects on the Ignition and Flame Extinction of High-temperature Fuel (고온연료의 점화 및 화염 소화특성에 미치는 복사효과)

  • Kim, Yu Jeong;Oh, Chang Bo;Choi, Byung Il;Han, Yong Shik
    • Fire Science and Engineering
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    • v.27 no.6
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    • pp.50-56
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    • 2013
  • The radiation effects on the auto-ignition and extinction characteristics of a non-premixed fuel-air counterflow field were numerically investigated. A detailed reaction mechanism of GRI-v3.0 was used for the calculation of chemical reactions and the optically-thin radiation model was adopted in the simulations. The flame-controlling continuation method was also used in the simulation to predict the auto-ignition point and extinction limits precisely. As a result, it was found that the maximum H radical concentration, $(Y_H)_{max}$, rather than the maximum temperature was suitable to understand the ignition and extinction behaviors. S-, C- and O-curves, which were well known from the previous theory, were identified by investigating the $(Y_H)_{max}$. The radiative heat loss fraction ($f_r$) and spatially-integrated heat release rate (IHRR) were introduced to grasp each extinction mechanism. It was also found that the $f_r$ was the highest at the radiative extinction limit. At the flame stretch extinction limit, the flame was extinguished due to the conductive heat loss which attributed to the high strain rate although the heat release rate was the highest. The radiation affected on the radiative extinction limit and auto-ignition point considerably, however the effect on the flame stretch extinction limit was negligible. A stable flame regime defined by the region between each extinction limit became wide with increasing the fuel temperature.

A Study on the Regional Learning Program in the lifelong Learning City - Based on an Empirical Case Study of the Geography Exploration Group in Guri, Gyeonggi Province - (평생학습도시의 지역학습 프로그램에 관한 연구 - 경기도 구리시의 지리 탐방대 활동을 중심으로 -)

  • Seo, Jeong-Hoon;Joo, Kyung-Sik
    • Journal of the Korean association of regional geographers
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    • v.16 no.5
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    • pp.572-589
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    • 2010
  • With the advent of lifelong learning society, most of the cities in Korea have been promoting the construction of lifelong learning city. At this point, the purpose of this study is to configure regional learning programs and apply them to the actual world. Important results of this study can be outlined as follows; First, the regional learning programs in the lifelong learning society are desirable to be configurated with the situated learning method focused on the characteristics of learners, instructors and the local contexts. In addition, the active training of regional human resources such as organizing learning circles and SERVICE-LEARNING through the participation of them is effective as a teaching method. Secondly, the consequence through the field excursion calling itself 'the geography exploration group', organized by the researcher and involved with participants together provoked the paradigm shift on their region and the regional identity. Thirdly, the active participation of local experts including geography teachers should be needed for the popularization of geography education. Hence, if we continue to develop the local learning programs tailored to regional traits and apply them to the actual world, geography education will play an important role to build the stable foundation in the lifelong learning society.

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Surgical Management and Outcome of Tethered Cord Syndrome in School-Aged Children, Adolescents, and Young Adults

  • Kang, Joon-Ki;Yoon, Kang-Jun;Ha, Sang-Su;Lee, II-Woo;Jeun, Sin-Soo;Kang, Seok-Gu
    • Journal of Korean Neurosurgical Society
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    • v.46 no.5
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    • pp.468-471
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    • 2009
  • Objective : The adolescent presentation of tethered cord syndrome (TCS) is well-recognized, but continues to pose significant diagnostic and management controversies. The authors conducted a retrospective study of clinical outcomes after surgical intervention in 24 school-aged children, adolescents, and young adults with TCS. Methods : All 83 patients with a lipomyelomeningocele (LMMC) underwent untethering surgery for caudal cord tethering between 1987 and 2007. The clinical charts and follow-up data were reviewed. Of these patients, 24 school-aged children, adolescents, and young adults with TCS were studied with respect to the clinical, radiologic, pathologic features, and surgical outcomes. Results : Untethering procedures were performed in 24 patients (age range, 7-25 years) for TCS of various origins (lipoma, lipomyelomeningocele, and tight filum terminale). Specific circumstances involving additional tugging of the already tight conus, and direct trauma to the back precipitated the onset of symptom in 50% of the patients. Diffuse and non-dermatomal leg pain, often referred to the anorectal region, was the most common presenting symptom. Progressive sensorimotor deficits in the lower extremities, as well as bladder and bowel dysfunction, were also common findings, but progressive foot and spinal deformities were noted less frequently. The most common tethered lesions were intradural lipomas, thickened filum and fibrous band adhesions into the placode sac. The surgical outcome was gratifying in relation to pain and motor weakness, but disappointing with respect to resolution of bowel and bladder dysfunction. Of the 24 patients with TCS, pre-operative deficits improved after surgery in 14 (58.3%). remained stable in 8 (33.4%). and worsened in 2 (8.3%). Conclusion : The pathologic lesions of tethered cord syndrome in school-aged children, adolescents, and young adults, are mostly intradural lipomas and tight filum. It is suggested that the degree of cord traction results in neurologic dysfunction in late life due to abnormal tension, aggravated by trauma or repeated tugging of the conus during exercise. Early diagnosis and adequate surgical release might be the keys to the successful outcome in school-aged children, adolescents, and young adults with TCS.

Effect of External Resistance on Electrical Properties of Two-Chamber type Microbial Fuel Cells (이형반응기 미생물연료전지의 전기적 특성에 미치는 외부저항의 영향)

  • Lee, Myoung-Eun;Jo, Se-Yeon;Chung, Jae-Woo;Song, Young-Chae;Woo, Jung-Hui;Yoo, Kyu-Seon;Lee, Chae-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.3
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    • pp.167-173
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    • 2011
  • The Effects of external resistance on electrical properties such as current density, power density and coulombic efficiency were investigated in two-chamber type MFCs using a ferricyanide as reducing agent. A stable electricity was produced when a constant time elapsed after innoculation of mixed cultures into the anode compartment; voltages from 0.13 to 0.16 V was measured at $50{\Omega}$ of external resistance. When the external resistance was increased, the current density decreased and the power density rapidly increased and then slowly decreased. Big variation of electrical properties was observed in high-current density region due to the concentration loss related with substrate consumption in repeated experiments changing the external resistance. The maximum power density ($175.8mW/m^2$) and coulombic efficiency (46.1%) were obtained at $100{\Omega}$ of the external resistance which is nearest with the internal resistance ($134{\Omega}$) of MFC system.

Characteristics of a Plasma-Dump Combustor for VOC Destruction (VOC 분해 플라즈마-덤프 연소기 특성)

  • Kim, Eun Hyuk;Chun, Young Nam
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.8
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    • pp.492-497
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    • 2015
  • VOCs (Volatile Organic Compounds) are generally generated in the painting process, or at the company and laundry where use organic solvents. The VOCs consist of various hydrocarbons and has low calorific value due to its dilution with atmospheric air. Therefore, the VOCs are difficult to burn by a conventional fuel combustor. In this study, a novel plasma dump combustor was proposed for the treatment of low calorific VOC gases. This combustor was designed a combination of the characteristics in a plasma burner, a dump combustor and a 3D matrix burner. The combustor has good structure for maintaining enough residence time and reaction temperature for stable flame formation and VOC destruction. For investigating the performance characteristics of the plasma dump combustor, an experiment was achieved for VOC feed rate, VOC injector position, etc. Toluene was used as a surrogate of VOC. The novel combustor gave better performance than a conventional combustor, showing that VOC destruction rate and energy efficiency were 89.64% and 12.27 kg/kWh respectively, at feeding rate of 450 L/min of VOC of 3,000 ppm of toluene concentration.

Body Temperature Monitoring Using Subcutaneously Implanted Thermo-loggers from Holstein Steers

  • Lee, Y.;Bok, J.D.;Lee, H.J.;Lee, H.G.;Kim, D.;Lee, I.;Kang, S.K.;Choi, Y.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.2
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    • pp.299-306
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    • 2016
  • Body temperature (BT) monitoring in cattle could be used to early detect fever from infectious disease or physiological events. Various ways to measure BT have been applied at different locations on cattle including rectum, reticulum, milk, subcutis and ear canal. In other to evaluate the temperature stability and reliability of subcutaneous temperature (ST) in highly fluctuating field conditions for continuous BT monitoring, long term ST profiles were collected and analyzed from cattle in autumn/winter and summer season by surgically implanted thermo-logger devices. Purposes of this study were to assess ST in the field condition as a reference BT and to determine any location effect of implantation on ST profile. In results, ST profile in cattle showed a clear circadian rhythm with daily lowest at 05:00 to 07:00 AM and highest around midnight and rather stable temperature readings (mean${\pm}$standard deviation [SD], $37.1^{\circ}C$ to $37.36^{\circ}C{\pm}0.91^{\circ}C$ to $1.02^{\circ}C$). STs are $1.39^{\circ}C$ to $1.65^{\circ}C$ lower than the rectal temperature and sometimes showed an irregular temperature drop below the normal physiologic one: 19.4% or 36.4% of 54,192 readings were below $36.5^{\circ}C$ or $37^{\circ}C$, respectively. Thus, for BT monitoring purposes in a fever-alarming-system, a correction algorithm is necessary to remove the influences of ambient temperature and animal resting behavior especially in winter time. One way to do this is simply discard outlier readings below $36.5^{\circ}C$ or $37^{\circ}C$ resulting in a much improved mean${\pm}$SD of $37.6^{\circ}C{\pm}0.64^{\circ}C$ or $37.8^{\circ}C{\pm}0.55^{\circ}C$, respectively. For location the upper scapula region seems the most reliable and convenient site for implantation of a thermo-sensor tag in terms of relatively low influence by ambient temperature and easy insertion compared to lower scapula or lateral neck.