• 한국자기학회지
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• 제5권1호
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• pp.64-70
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• 1995

$ThMn_{12}$ 구조를 갖는 $NdFe_{10.7}TiM_{0.3}(M=B,\;Ti)$의 결정학적 및 자기적 성질을 X선 회절법과 VSM, $M\"{o}ssbauer$분광법으로 연구하였다. $NdFe_{10.7}TiM_{0.3}(M=B,\;Ti)$합금은 알곤가스 분위기의 아크 용해로에서 제조하였다. $NdFe_{10.7}TiM_{0.3}$의 결정구조는 순수 단일상의 tetragonal구조를 갖고 있으며 $a_{0}=8.587\;{\AA},\;c_{0}=4.788\;{\AA}$의 격자상수를 결정하였다. $M\"{o}ssbauer$ spectrum은 13 K 부터 770 K 영역까지 취하였으며 Curie 온도는 $NdFe_{10.7}TiM_{0.3}$의 경우 $570{\pm}3\;K$로 결정하였다. $NdFe_{10.7}TiM_{0.3}(M=B,\;Ti)$은 $8i_{1},\;8i_{2},\;8j_{1},\;8j_{2}$ 및 8f의 5 set의 Fe 이온의 subspectra로 분석하였다. $NdFe_{10.7}TiM_{0.3}$의 실온에서 Fe-site $8i_{1},\;8i_{2},\;8j_{1},\;8j_{2}$ 및 8f는 16.4, 8.2, 14.8, 21.3 및 39.3%의 면적비를 각각 가지고 있었다. 초미세자기장은 $H_{hf}(8i)>H_{hf}(8j)>H_{hf}(8f)$비로 감소함을 알았다.

• 한국환경농학회지
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• 제20권1호
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• pp.28-33
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• 2001

본 시험에서 사용된 상추는 대조구인 양액과 양액에 30 mM $KNO_3$, 혹은 양액에 50 mM $KNO_3$를 첨가한 염류농도가 다른 3가지의 양액에서 재배하였으며 이들 양액의 EC는 각각 1.0, 4.5, 6.5 ds/m이었다. 상추의 생육은 처리간에 차이를 보였으며 $KNO_3$를 첨가하여 염류농도를 높여준 용액에서 재배한 상추는 잎끝이 마르는 생리적 장해를 보이면서 발아율의 감소는 물론 초장, 경태, 엽장 및 엽폭 등 성장이 대조구와 비교하여 현저히 부진하였다. 이들 양액에서 자란 상추의 뿌리로부터 마이크로솜을 분리하여 ATPase의 특성을 조사하였다. 마이크로솜 ATPase의 활성은 대조구에 비하여 양액에 30 mM $KNO_3$와 50 mM $KNO_3$를 첨가한 용액에서 자란 상추에서 더 높았다. 상추뿌리로부터 분리한 마이크로솜 ATPase의 총활성은 재배양액 조건에 관계없이 pH 7.0에서 최대로 나타났다. ATPase의 활성은 반응용액의 $K^+$ 농도를 증가시키면 증가하였고 반응용액에 $Na^+$ 농도를 증가시키면 감소하였다. $K^+$에 의한 활성증가 효과는 양액에서 재배한 대조구보다 $KNO_3$를 첨가하여 EC를 높여준 양액에서 재배한 상추뿌리의 마이크로솜 ATPase에서 더 크게 나타났다. 이러한 결과는 생육환경내 $KNO_3$ 농도의 증가에 따라 뿌리의 생리활성을 조절하는 ATPase의 활성이 증가함을 보여준다.

• 환경위생공학
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• 제20권4호통권58호
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• pp.21-30
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• 2005

This research was performed to measure the concentration distribution of bioaerosol in apartment houses in the region of Chungnam (Chunan, Asan) for 1 month, December, 2004. The results are as follows. 1. By using SDA method, the average concentration of total microbe and fungus in the air inside and outside apartment house below 4 years are $69,42cfu/m^3\;and\;15.66cfu/m^3$, while apartment house over 4 years, $214.58cfu/m^3\;and\;216.43cfu/m^3$, respectively With gravitational sedimentation method, the average concentration of total microbe and fungus of apartmenthouse below 4 years are $100.63cfu/m^3\;and\;22.83cfu/m^3$, while apartment house over 4 years, $216.43cfu/m^3\;and\;70.000cfu/m^3$, respectively. 2. The I/O ratio of floating germ of apartment house below 4 years and over 4 years are 2.87 and 5.12 for total microbe, and 3.32 and 8.28 for fungus, respectively. The I/O ratio of falling germ of apartment house below 4 years and over 4 years are 1.55 and 2.81 for total microbe, and 2.85 and 4.08 for fungus, respectively. The apartment house below 4 years shows a low I/O ratio in all cases. 3. The difference in concentration of microbe between inside master bedroom and living room of apartment house below 4 years is $13.183cfu/m^3$, total microbe, and $4.787cfu/m^3$, fungus, while, apartment house over 4 years, $43.531cfu/m^3$, total microbe, and $21.932cfu/m^3$, fungus. The measured differences are statistically significant. 4. Air sampler was used to verify the difference in concentration of microbe with the age of apartment house. The difference in concentration of total microbe and fungus for outside apartment house below 4 years and over 4 years are $49.82cfu/m^3$ and $3.78cfu/m^3$, respectively. The difference of inside living room shows $160.23cfu/m^3$ for total microbe and $28.01cfu/m^3$ for fungus, and the difference of inside master bedroom shows $225.43cfu/m^3$ for total microbe and $56.73cfu/m^3$ for fungus. The differences are statistically significant. The difference in concentration of outside apartment house below 4 years and years 4 years are $34.66cfu/m^3$, total microbe, and $15.66cfu/m^3$, fungus, while inside apartment house below 4 years and over 4 years, $196.93cfu/m^3,\;and\;78.67cfu/m^3$, respectively. The measured differences are statistically significant.

• 약학회지
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• 제53권3호
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• pp.125-129
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• 2009

H2-M3 (M3) is a unique antigen presenting molecule which provides N-formylated peptide to certain type of T cells. Previous observation indicated that NK cell activity is significantly diminished during listerial infection in $H2-M3^{-/-}$ mice. To explore the possibility that M3 expression directly effect on NK cell activity, we measured NK cell activity with or without stimulation of N-formylated peptide on antigen presenting cells. Results indicated that the expression of M3 is not directly influence on NK cell activity. Further study will be focused on the indirect effect of M3 on regulating NK cell activity.

• 한국초등과학교육학회지:초등과학교육
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• 제28권2호
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• pp.142-153
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• 2009

The purpose of this study was to survey primary students' perception of the global and local environmental issues. The subjects were 853 fifth primary students in Seoul, Busan, Daejeon, Anyang, Gimpo and Cheongju. The results were as follows: First, the perception level of the global environmental issues were global warming (M=3.99), drinking-water pollution (M=3.92), acid rain (M=3.77), yellow dust (M=3.66), ozone depletion (M=3.57), deforestation in tropical areas (M=3.52), desertification (M=3.36), biodiversity (M=3.40) and their perception level of local environmental issues were waste disposal (M=3.87), air pollution (M=3.74), bad smell (M=3.70), noise (M=3.61), river pollution (M=3.57), soil pollution (M=3.44). Second, it was shown that the metropolitan students' perception levels of environmental issues were higher than the non-metropolitan students'. There wasn't a significant difference in the perception levels of two scale environmental issues and characteristics for sex (p>.05). Third, the result of analyzing on the effects between characteristics was that the factors like 'environmental interest' and 'impact on personal life' had a strong influence on the 'behavior will' to solve the global environmental issues, and 'environmental interest' and 'personal knowledge' had a strong influence on the 'behavior will' to solve the local environmental issues. Fourth, the result of analyzing on the characteristics according to the types of the environmental issues showed that 'personal knowledge', 'environmental interest' and 'behavior will' were high in the global environmental issues (p<.01) and 'virtual contamination', 'human responsibility' and 'impact on personal life' were high in the local environmental issues (p<.05).

• BMB Reports
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• 제30권4호
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• pp.240-245
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• 1997

Interactions between ganglioside $G_{M3}$ and glucose transporter, GLUT1 were studied by measuring the effect of $G_{M3}$ on steady-state and time-resolved fluorescence of purified GLUT1 in synthetic lipids and on the 3-O-methylglucose uptake by human erythrocytes. The intrinsic tryptophan fluorescence showed a GLUT 1 emission maximum of 335 nm, and increased in the presence of $G_{M3}$ by 12% without shifting the emission maximum, The fluorescence lifetimes of intrinsic tryptophan on GLUT1 consisted of a long component of 7.8 ns and a short component of 2,3 ns and $G_{M3}$ increased both lifetime components. Lifetime components were quenched by acrylamide and KI. Acrylarnide-mduced quenching of long-lifetime components was partly recovered by $G_{M3}$ However. KI-induccd quenching of short- and long-lifetime components was not rescued by $G_{M3}$. The anisotropy of 1.6-diphenyl-1.3.5-hexatriene (DPH)-probed dimyristoylphosphatidylcholine (DMPC) model membrane was also increased with $G_{M3}$ incorporation, The transport rate of 3-O-methylglucose increased by 20% with $G_{M3}$ incorporation on the erythrocytes, Therefore, $G_{M3}$ altered the environment of lipid membrane and induced the conformational change of GLUT1.

• Clinical and Experimental Reproductive Medicine
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• 제36권3호
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• pp.175-186
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• 2009

목 적: Hypoxanthine (Hx)과 FSH가 미성숙난자의 배양에 미치는 영향을 관찰하기 위해 미성숙난자를 배양하여 GVBD, MII기 발생률을 비교 관찰하였다. 연구방법: 단순배양액인 BSAL-XI-HTF 배양액을 사용하여 (1) 0.3% BSA mBASAL-XI-HTF (0.3% BSA 배양액), (2) 0.1 IU/ml FSH를 첨가한 0.3% BSA mBASAL-XI-HTF (FSH 0.3% BSA 배양액), (3) 10% FBS mBASAL-XI-HTF (10% FBS 배양액), (4) 0.1 IU/ml FSH를 첨가한 10% FBS mBASAL-XI-HTF (FSH 10% FBS 배양액)의 4종류의 배양액을 만들었고, 각 종류의 배양액에서 생쥐 난구세포로 둘러싸인 미성숙난자의 성숙을 3, 6, 18시간별로 비교 관찰하였다. 각 배양액에 1 mM, 2 mM, 4 mM 농도의 미성숙난자성숙억제제인 Hx을 섞어 난자의 성숙억제양상을 관찰하였고 GVBD와 MII기 발생률을 비교 관찰하였다. 결 과: Hx을 첨가하지 않은 4종류의 배양액에서 미성숙난자의 자연성숙은 3시간 내에 대부분 GVBD가 발생하였고 MII기로의 발육은 6시간 이후 발생하였다. 18시간 후 각 군의 배양에서 모두 유사한 GVBD 발생률을 보였다. 1 mM, 2 mM, 4 mM Hx 농도의 0.3% BSA 배양액과 10% FBS 배양액에서 난자의 성숙억제양상을 비교해 보면 4 mM 농도의 Hx 배양액에서 18시간 동안 완전한 성숙억제를 보였다. 2 mM 농도의 Hx 배양액에서도 18시간 배양까지 억제를 보였으나 4 mM 농도의 Hx 배양액보다 작은 난자성숙억제양상을 보였다. 1 mM 농도의 Hx 배양액에서는 모두 난자성숙억제를 보이지 못했다. FSH를 첨가한 배양액에서는 2 mM 농도의 Hx 뿐만 아니라 1 mM 농도의 Hx 첨가에서도 초기 3시간까지 GVBD 성숙이 억제되었다. 또 같은 농도의 Hx을 함유하고 FSH를 첨가하지 않은 배양액에 비해 FSH를 첨가한 배양액에서 3시간, 6시간 동안 GVBD 발생을 더 억제하였다. 그러나 18시간 배양 후 난자성숙이 회복됨을 보였다. 이 결과로 FSH가 배양초기에 난자성숙을 억제하나 후기에는 성숙을 촉진함을 알 수 있었다. 18시간 후 MII기발육은 4 mM 농도의 Hx을 함유한 모든 배양액에서 낮은 발생률을 보였고, FSH를 함유한 10% FBS 배양액에 1 mM, 2 mM의 낮은 농도의 Hx을 첨가한 배양액은 다른 배양액에 비해 통계학적으로 높은 MII기 발생률을 보였다. 결 론: 본 실험에서 낮은 농도의 Hx과 FSH는 FBS를 함유한 배양액에서 미성숙난자의 초기배양 동안 성숙을 억제한 후 MII기 성숙을 촉진함을 알 수 있었다.

• 한국대기환경학회지
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• 제29권1호
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• pp.86-96
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• 2013

The realtime monitoring of radon ($^{222}Rn$) concentrations has been carried out from Gosan site, Jeju Island for three years of 2006~2008, in order to evaluate the background level and timely variational characteristics of atmospheric radon. The mean concentration of radon measured during the studying period was $2965mBq/m^3$ with its annual mean values in the range of $2768{\sim}3124mBq/m^3$. The relative ordering of the seasonal mean concentrations was seemed to vary such as winter ($3578mBq/m^3$) > fall ($3351mBq/m^3$) > spring ($2832mBq/m^3$) > summer ($2073mBq/m^3$). The monthly mean concentrations were in the order of Jan>Feb>Oct>Nov>Dec>Mar> Sep>Apr>May>Jun>Aug>Jul, so that the highest January value ($3713mBq/m^3$) exceeded almost twice as the July minimum ($1946mBq/m^3$). The hourly concentrations in a day showed the highest level ($3356mBq/m^3$) at around 7 a.m., increasing during nighttime, while reaching the lowest ($2574mBq/m^3$) at around 3 p.m. From the backward trajectory analysis for a continental fetch of radon, the high concentrations (10%) of radon matched with the air mass moving from the Asia continent to Jeju area. In contrast, the low concentrations (10%) of radon were generally correlated with the air mass of the North Pacific Ocean. In comparison by sectional inflow pathways of air mass, the radon concentrations were relatively high from the north China and the Korean peninsula.

• 전자공학회논문지
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• 제52권3호
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• pp.48-55
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• 2015

본 논문은 $3^{rd}$ Generation Partnership Project(3GPP) Long Term Evolution-Advanced(LTE-A) 시스템을 기반으로 소량의 데이터를 송수신하는 M2M 기기가 무수히 존재하는 상황에서 발생할 수 있는 문제점을 고찰하고 이를 해결하기 위한 기술을 제시한다. 특별히, 무수히 존재하는 M2M 기기들로 인한 랜덤 액세스 채널의 부족과 이로 인한 지연(latency) 증가 문제를 해결하기 위해 M2M 그룹화 기술에 사용자 특성별로 구별하여 허용 가능한 액세스 시도 확률을 차별적으로 제어한다. M2M 기기들을 그룹화 하여 PRACH(Physical Random Access CHannel)의 랜덤 액세스(Random Access)를 시도하는 단말 수를 감소시키는 효과를 획득함과 동시에 셀룰러(Cellular) 통신을 하는 단말기와의 충돌을 줄임으로써, 기존 이동 통신 단말과 M2M 기기들이 공존하는 시스템의 랜덤 액세스 평균 지연(average latency) 증가 문제를 해결할 수 있음을 실험을 통해 증명한다.

• 한국환경과학회지
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• 제18권5호
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• pp.479-487
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• 2009

Because of the building is made airtight, Indoor Air Quality(IAQ) is go from bad to worse. There are many source of indoor pollution in any home. These include irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue. Such immediate effects are usually short-term and treatable. In this study was measured and analyzed VOCs exposure levels and characteristic of Indoor air pollutant from new apartments in Korea. VOCs were measured indoor pre-residential and residential in new apartment and analyzed GC/MS. The concentration levels of indoor respirable TVOC were found to be higher than those of outdoor TVOC for new apartments. Before occupation, the average indoor and outdoor concentrations were 1498.61 $ug/m^3$ and 468.38 $ug/m^3$, respectively. After being occupied, the average indoor and outdoor concentration were 847.04 $ug/m^3$ and 102.84, respectively. The concentrations of TVOC in new apartments before occupation were shown in the order of Toluene(328.12 $ug/m^3$) > m,p-Xylene(163.67 $ug/m^3$) > Ethy1benzene(80.70 $ug/m^3$>o-XYlene (67.04$ug/m^3$). In addition, the TVOCs concentrations after occupation were also found in the order of Toluene (272.28 $ug/m^3$) > m.p-Xylene(121.79 $ug/m^3$) > Ethylbenzene(53.92 $ug/m^3$)>O-Xylene(24.94 $ug/m^3$). As a result, the concentrations of VOCs in new apartment houses were shown to be affected by indoor environment according activity patterns. So new apartments need to be controled in indoor air quality so that the residents can have more comfortable and healthier living environment.