• 한국대기환경학회지
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• 제9권1호
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• pp.81-92
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• 1993

A purpose of this study was carried out to investigate the concentrations of four elements of PAHs(Polycyclic Aromatic Hydrocarbons) in suspended particulate matters of underground shopping stores in Seoul city. The particulate matters were collected at five underground shopping stores(Yongdungpo, Myongdong, Ulchiro, Express Terminal, Chamshil) in the Seoul area during February-October, 1992. Samples were collected using cascade impactor of low volumn air sampler and were analysed using High Performance Liquid Chromatography(HPLC) with fluorescence detector. Calibration on HPLC analyse is nearly accord with retention time between the standard solution and the samples. Analysed results obtained favorable analysing recovery rate of 97.3% and coefficient of variation of 1.60%. Mean concentrations of suspended particulate matters in five underground shopping stores wre 216.3 g/$m^3$ and observed higher at fine particles(117.2 g/$m^3$) which is respirable particulates than coarse particles(99.2 g/$m^3$). Concentrations of four species PAH were determined with anthracene of 16.8ng/$m^3$, fluoranthene of 72.3ng/$m^3$, benzo(a)pyrene of 0.54ng/$m^3$, and benzo(k)fluoranthene of 0.29ng/$m^3$, respectively. Fluoranthene levels were significantly higher than those levels in other components. PAHs concen-tration at shopping areas showed 21.3ng/$m^3$ in Yongdungpo, 35.1ng/$m^3$ in Myongdong, 23.4ng/$m^3$ in Ulchiro, 11.1ng/$m^3$ in Express Terminal, and 21.4ng/$m^3$ in Chamshil, respectively. Particularly, benzo(a)pyrene and benzo(k)-fluoranthene were detected over 83 percentage in fine particles, while fluoranthene wre highly detected in coarse particles. Also, higher concentrations of benzo(a)pyrene, benzo(k)fluoranthene were found in winter while levels of anthracene and fluoranthene were found higher in summer than other seasons.

• The Korean Journal of Physiology and Pharmacology
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• 제3권2호
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• pp.157-164
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• 1999

To determine molecular mechanisms of Aquaporin-CD (AQP2) gene regulation, the promoter region of the AQP2 gene was examined by transiently transfecting a promoter-luciferase reporter fusion gene into mouse renal collecting duct cell lines such as mIMCD-3, mIMCD-K2, and M-1 cells, and NIH3T3 mouse embryo fibroblast cells. PCR-Southern analysis reveals that mIMCD-3 and mIMCD-K2 cells express AQP2, but M-1 and NIH3T3 cells do not, and that the treatment with cpt-cAMP $(400\;{\mu}M)$) or forskolin/isobutylmethylxanthine (IBMX) increased the AQP2 expression in IMCD cells. In both IMCD and NIH3T3 cells, the constructs containing the promoter of AQP2 gene showed promoter activities, indicating lack of tissue-specific element in the 1.4 kb 5'-flanking region of the mouse AQP2 gene. Luciferase activity in the IMCD cells transfected with the construct containing 5-flanking region showed responsiveness to cpt-cAMP, indicating that the 1.4 kb 5'-flanking region contains the element necessary for the regulatory mechanism by cAMP. The promoter-luciferase constructs which do not have a cAMP-responsible element (CRE) still showed the cAMP responsiveness in IMCD cells, but not in NIH3T3 cells. Increase in medium osmolarity did not affect AQP2 promoter activity in mIMCD-K2 cells. These results demonstrate that AQP2 gene transcription is increased with cAMP treatment through multiple motifs including CRE in the 5'-flanking region of the gene in vitro, and the regulatory mechanism may be important for in vivo regulation of AQP2 expression.

• 천문학회보
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• 제41권1호
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• pp.61.2-61.2
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• 2016

우리는 1997년부터 현재까지 보현산천문대 1.8 미터 망원경과 이 망원경에 부착한 1K CCD, 2K CCD와 4K CCD를 이용하여 가까운 북반구 구상성단에 대하여 (U)BVI CCD 측광 관측을 수행해오고 있다. 2K CCD를 통한 관측 자료를 통해서 우리는 북반구 구상성단 M3, M13, M15, M53과 M92의 정밀한 색-등급도를 도출할 수 있었다. 이 색-등급도를 통해서 M3, M13, M15와 M92의 경우는 밝은 계열 별(특히 점근거성가지별)의 특성 및 종족비(R과 R2)와 적색거성가지별의 광도함수를 유도하였고, M53과 M92의 경우는 상대나이를 유도함으로써 구상성단의 제 2 계수 문제를 규명하고자 하였다. 우리는 추가로 북반구 구상성단 M5, M10과 M71의 정밀한 색-등급도를 도출하여 밝은 계열 별의 특성을 규명하고 적색거성가 지별의 광도함수를 유도함으로써 종족 II 항성의 진화 문제를 연구하고자 한다. 현재 운영 중인 4K CCD를 통해서 구상성단 M2, M3, M5, M13, M15, M53, M71과 M92를 관측하고 있으며 2K CCD 경우보다 어두운 주계열성까지의 측광 자료 도출에 주목적이 있다($V{\approx}23$ 등급까지). 도출한 측광 자료를 2K CCD 측광 자료와 결합하여 북반구 구상성단 구성별의 고유운동 자료를 도출하고자 하며 이의 활용 방안에 대하여 논의하고자 한다. 더불어 그 동안 보현산천문대에서의 관측 여건에 대해서도 논의하고자 한다.

• 한국식물병리학회지
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• 제3권3호
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• pp.159-163
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• 1987

우리나라에 발생하고 있는 뿌리혹선충의 Race를 조사하고 기후에 따른 종의 분포 및 밀도를 파악하기 위하여 3226포장에서 시효를 채취하여 Baermann's funnel법으로 선충을 추출하여 선충의 형태와 International Meloidogyne Project의 Differenctial Host Test Method로 조사하였다. 우리나라에 있어서 뿌리혹선충의 종류별 분포는 M. hapla가 중부지방에서, M. incognita가 남부지방에서 우점종을 이루었고, M. arenaria는 남부지방에서 검출율이 다소 높았으며 M. javanica는 제주와 남부해안지방을 중심으로 분포하고 있었다. 우리나라에 분포하고 있는 뿌리혹선충의 종별 Race는 M. arenaria에서 Race 1과 Race 2, 그리고 M. incognita에서 Race 1, Race 2 및 Race 3이 알려졌으며, 이 중에 M. arenaria Race 1과 M. incognita Race 3은 우리나라에서 처음으로 보고되었다.

• 한국전기전자재료학회논문지
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• 제30권1호
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• pp.7-12
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• 2017

3YSZ + (x) $Al_2O_3$ composites (x = 20, 40, 60, 80 wt%) were fabricated and the influences of particle sizes of $Al_2O_3$ on their microstructures and mechanical properties were investigated with XRD, SEM, vickers hardness and fracture toughness. $Al_2O_3$-3YSZ composites containing $Al_2O_3$ powder of a $0.3{\mu}m$ and an $1.0{\mu}m$, which are here in after named as $Al_2O_3$($0.3{\mu}m$)-3YSZ and $Al_2O_3$($1.0{\mu}m$)-3YSZ, respectively, were made by mixing raw materials, uni-axial pressing and sintering at $1,400^{\circ}C$, $1,500^{\circ}C$, and $1,600^{\circ}C$. $Al_2O_3$($0.3{\mu}m$)-3YSZ composites show the higher density and the better mechanical properties than $Al_2O_3$($1.0{\mu}m$)-3YSZ composites. The Vickers hardness of the $Al_2O_3$($0.3{\mu}m$)-3YSZ composites show a peak value of 1,997 Hv at the content of 60 wt% $Al_2O_3$, which is a slightly higher value in comparison with 1,938 Hv of the $Al_2O_3$($1.0{\mu}m$)-3YSZ composite. However, the fracture toughness of $Al_2O_3$-3YSZ composites monotonically increases with decreasing the content of $Al_2O_3$ without any peak values. $Al_2O_3$($0.3{\mu}m$)-3YSZ and $Al_2O_3$($1.0{\mu}m$)-3YSZ composites sintered at $1,600^{\circ}C$ have a maximum value of a $6.9MPa{\cdot}m^{1/2}$ and a $6.2MPa{\cdot}m^{1/2}$, respectively at the composition of containing 20 wt% $Al_2O_3$. It should be noticed that the mechanical properties and the sintering density of the $Al_2O_3$-3YSZ composites can be enhanced by using more fine $Al_2O_3$ powder due to their denser microstructure and smaller grain size.

• 자원환경지질
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• 제42권6호
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• pp.591-598
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• 2009

본 연구에서는 남한일대에서 화성암, 변성암, 퇴적암의 총 2511개의 암석을 채취하여 열물성을 측정하고 각 암종별로 일반적인 통계분석을 실시하였다. 화성암, 변성암, 퇴적암의 평균 열전도도는 각각 3.10W/m-K, 3.76W/m-K, 3.54W/m-K 이다. 화성암의 암석 분류에 따라 심성암, 반심성암, 화산암으로 분류하였으며, 각각의 평균 열전도도는 3.16 W/m-K, 3.26 W/m-K, 2.77 W/m-K이다. 퇴적암에서 쇄설성 퇴적암 보다 비쇄설성 퇴적암의 열전도도가 비교적 높은 분포를 보이고 있다. 측정된 암석의 시대별 열전도도는 고생대가 중생대 보다 높은 나타나며, 이는 높은 열전도도를 갖는 구성 광물에 의한 것으로 판단된다. 암석의 공극률은 열전도도에 영향을 미치는 요소이며 퇴적암의 경우 공극률이 증가할 수록 열전도도는 대체적으로 감소하는 경향을 보인다. 암석의 열전도도와 열확산율은 선형의 상관관계를 보이며, 화성암, 변성암, 퇴적암의 선형 회귀분석 상관계수는 각각 0.775, 0.855 0.876로 높은 값을 보인다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권3호
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• pp.293-303
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• 1999

The influences of specific protein phosphatase and protein kinase inhibitors on the ATP-sensitive $K^+\;(K_{ATP})$ channel-opening effect of pinacidil were investigated in single rat ventricular myocytes using patch clamp technique. In cell-attached patches, pinacidil $(100\;{\mu}M)$ induced the opening of the $K_{ATP}$ channel, which was blocked by the pretreatment with H-7 $(100\;{\mu}M)$ whereas enhanced by the pretreatment with genistein $(30\;{\mu}M)$ or tyrphostin A23 $(10\;{\mu}M)$. In inside-out patches, pinacidil $(10\;{\mu}M)$ activated the $K_{ATP}$ channels in the presence of ATP (0.3 mM) or AMP-PNP (0.3 mM) and in a partial rundown state. The effect of pinacidil $(10\;{\mu}M)$ was not affected by the pretreatment with protein tyrosine phosphatase 1B $(PTP1B,\;10\;{\mu}g\;ml^{-1}),$ but blocked by the pretreatment of protein phosphatase 2A $(PP2A,\;1\;U\;ml^{-1})$. In addition, pinacidil $(10\;{\mu}M)$ could not induce the opening of the reactivated $K_{ATP}$ channels in the presence of H-7 $(100\;{\mu}M)$ but enhanced it in the presence of ATP (1 mM) and genistein $(30\;{\mu}M).$ These results indicate that the $K_{ATP}$ channel-opening effect of pinacidil is not mediated via phosphorylation of $K_{ATP}$ channel protein or associated protein, although it still requires the phosphorylation of serine/threonine residues as a prerequisite condition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.47-48
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• 2015

As the power system develops rapidly into a smarter and more flexible state, so must the communication technologies that support it. Machine to machine (M2M) communication in Smart Grid environment has been discussed in European Telecommunications Standards Institute (ETSI). The power system is not easily replaceable, due to system replacement cost. The M2M gateway is required in other to improve interoperability in M2M environment. The Distributed Network Protocol 3.0 (DNP3.0) is the most important standard in the SCADA systems for the power. It has been used for device data collection/control in Substation Systems, Distribution Automation System. If the DNP3.0 data model is combined with a set of contemporary web protocols, it can result in a major shift. We selected Constrained Application Protocol (CoAP) based on RESTful as M2M protocol. It is a specialized web transfer protocol for use with constrained nodes and constrained networks. We have used the OPNET Modeler 17.1 in order to verity the SOAP versus CoAP. In this paper, we propose the CoAP-based M2M Gateway to Distribution Automation system using DNP3.0 in Smart Grid Environment.

• Environmental Analysis Health and Toxicology
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• 제24권3호
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• pp.203-211
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• 2009

A lesser degree of research is available with respect to indoor radon characteristics associated with occupants' exposure. The present study evaluated the radon levels in several public-access buildings or underground facilities, and their temporal variation in underground facilities. Radon measurements were conducted in 2005 and 2006, utilizing a continuous radon detector. A solid alpha detector (RAD7) was utilized to measure indoor radon levels. The mean radon concentrations obtained from the building or facilities were in a descending order: platforms of Daegu subway line 2, 2005 (32 $Bq/m^3$), hot-air bathroom (14 $Bq/m^3$), basement of office building (14 $Bq/m^3$), underground parking garage (14 $Bq/m^3$), underground shop (12 $Bq/m^3$), nursery (10 $Bq/m^3$), platforms of Daegu subway line 2, 2006 (9.0 $Bq/m^3$), platforms of Daegu subway line 1, 2006 (8.9 $Bq/m^3$), supermarket (7.9 $Bq/m^3$), hospital (7.3 $Bq/m^3$), and second-floor of office building (5.7 $Bq/m^3$). In general, underground-level facilities exhibited higher radon levels as compared with ground-level facilities. It was suggested that ventilation is an important parameter regarding the indoor levels of a subway. There was a decreasing or increasing trend in hourly-radon levels in a subway, whereas no trend were observed in a basement of office building. In addition, the radon levels in the subway lines 1 and 2 varied according to the platforms. The radon levels in the present study were much lower than those of previous studies. The average annual effective dose (AED) of radiation from indoor radon exposure was estimated to be between 0.043 and 0.242 mSv/yr, depending on facility types. These AEDs were substantially lower than the worldwide average AED (2.4 mSv/yr).

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1149-1153
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• 2014

Real-time monitoring of hourly atmospheric radon (Rn-222) concentration was performed throughout 2011 at Gosan station, Jeju Island, one of the least polluted regions in Korea, in order to characterize the background levels, and temporal variations on diurnal to seasonal time-scales. The annual mean radon concentration for 2011 was $2527{\pm}1356$ mBq $m^{-3}$, and the seasonal cycle was characterized by a broad winter maximum, and narrow summer minimum. Mean monthly radon concentrations, in descending order of magnitude, were Oct > Sep > Feb > Nov > Jan > Dec > Mar > Aug > Apr > Jun > May > Jul. The maximum monthly mean value (3595 mBq $m^{-3}$, October), exceeded the minimum value (1243 mBq $m^{-3}$, July), by almost a factor of three. Diurnal composite hourly concentrations increased throughout the night to reach their maximum (2956 mBq $m^{-3}$) at around 7 a.m., after which they decreased to their minimum value (2259 mBq $m^{-3}$) at around 3 p.m. Back trajectory analyses indicated that the highest radon events typically exhibited long-term continental fetch over Asia before arriving at Jeju. In contrast, low radon events were generally correlated with air mass fetch over the North Pacific Ocean. Radon concentrations typical of predominantly continental, and predominantly oceanic fetch, differed by a factor of 3.8.