• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.3
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• pp.158-164
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• 2002

2-6 GHz digital phase shifter module has been designed and fabricated. For the broadband operation and performance, MMIC phase shifter chip for phase shifter module was designed and fabricated by using the reflection-type circuits with Lange coupler. The fabricated phase shifter module shows 6.1$^{\circ}$RMS phase error, 13.5 dB maximum insertion loss, and 8 dB and 10 dB input and output return losses, respectively. Computer controlled measurement systems are realized in order to get the measured data of 32 phase states. The RMS insertion phase error and the average insertion loss deviation among 8${\times}$8 modules for the phased-array system are less than ${\pm}$0.5$^{\circ}$and ${\pm}$0.5 dB, respectively. The size of fabricated phase shifter module is 45 ${\times}$ 22.5 ${\times}$60㎣.

• Annual Conference on Human and Language Technology
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• 2005.10a
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• pp.21-27
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• 2005

본 논문에서는 국가에서 추진하는 차세대신성장동력산업과 관련된 특정 분야('바이오 신약/장기' 분야 중 '면역 기능 제어')를 선택하여, 기구축된 면역학 전문용어사전을 비롯하여 의학용어사전, 표준국어대사전 등을 참조하여 핵심 용어와 관련 용어를 중심으로 면역학 시소러스(어휘 3,462개) 및 온톨로지(개념 노드 4,703개)를 구축하였다. 이것은 전문용어사전부터 온톨로지에 이르기까지 통일화된 표준 체계를 가지고 있으며, 도메인 온톨로지를 구축하여 향후 온톨로지 개발 방향을 설정할 수 있는 계기가 되었다고 할 수 있다. 또한 면역학 시소러스는 검색의 성능을 향상시킬 수 있도록 충분한 양의 데이터를 구축하였고 면역학 온톨로지는 언어처리적 관점에서의 온톨로지를 표현하였다. 이는 정보검색에서의 효율성을 비롯하여, 특정 웹 온톨로지 언어를 이용한 웹 온톨로지로의 변환성, 대규모 도메인 온톨로지라는 점에서 의미를 가진다고 할 수 있다.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.77.2-77.2
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• 2010

A high redshift quasar is useful to investigate the early part of our universe. Since they are one of the brightest objects in the early universe, they can provide us with clues of the growth of super massive black holes and the early metal enrichment history. To discover the high redshift quasars, we designed a survey of wide area and moderate depth; Infrared Medium-deep Survey (IMS), a J-band imaging survey of ~200 $deg^2$ area where the multi-wavelength data sets exist. To obtain the J-band data, we are using the United Kingdom Infra-Red Telescope (UKIRT), and so far we have covered ~20 $deg^2$ with Y- or J-bands over three observing runs during 2009. We used color-color diagrams of multi-wavelength bands including i, z, Y, J, K, $3.6{\mu}m$ and $4.5{\mu}m$ to select high redshift quasars. The major challenge in the selection is many M/L/T dwarfs, low redshift galaxies, and instrumental defects that can be mistaken as a high redshift quasar. We describe how such contaminating sources can be excluded by adopting multiple color-color diagrams and eye-ball inspections. So far, our selection reveals two quasar candidates at z~7.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.37.1-37.1
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• 2010

A high redshift quasar is useful to investigate the early part of our universe. Since they are one of the brightest objects in the early universe, they can provide us with clues of the growth of super massive black holes and the early metal enrichment history. To discover the high redshift quasars, we designed a survey of wide area and moderate depth; Infrared Medium-deep Survey (IMS), a J-band imaging survey of ~200 deg2 area where the multi-wavelength data sets exist. To obtain the J-band data, we are using the United Kingdom Infra-Red Telescope (UKIRT), and so far we have covered~40 deg2 with Y- or J-bands over 36 observing nights. We used color-color diagrams of multi-wavelength bands including i, z, Y, J, K, $3.6{\mu}m$ and $4.5{\mu}m$ to select high redshift quasars. The major challenge in the selection is many M/L/T dwarfs, low redshift galaxies, and instrumental defects that can be mistaken as a high redshift quasar. We describe how such contaminating sources can be excluded by adopting multiple color-color diagrams and eye-ball inspections. So far, our selection reveals one quasar candidates at z~7 and a few candidates at z~6. In this poster presentation, we will update the current status of the quasar selection in the IMS fields.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.202.1-202.1
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• 2014

최근 대용량 에너지 저장장치로 사용하고자 하는 리튬-공기전지는 리튬 음극과 액체 전해질 사이의 화학적 불안정성이 문제가 되고 있다. 또한 리튬이온전지는 액체전해질의 사용으로 인해 폭발 등의 안정성 문제가 대두되고 있는 실정이다. 때문에 리튬-공기전지에서 리튬 음극을 액체 전해질로부터 보호할 수 있으며, 리튬이온전지의 액체전해질과 대체하였을 때 전극과도 안정한 고체전해질의 연구가 필요하다. 고체전해질은 구조적으로 crystalline, glassy, 폴리머로 나눌 수 있는데, 이 중 crystalline 구조의 고체전해질은 glassy 및 폴리머 고체전해질에 비해 상온에서 비교적 이온전도도가 높다고 알려져 있다 [1]. 그러나 이온전도도가 높은 황화물 및 질화물 고체전해질은 수분에 민감한 반면 [2,3], 산화물 계열의 물질은 안정할 것으로 예상된다. 본 연구에서는 이온전도도가 높은 산화물인 lithium lanthanum titanate ($Li_{0.5}La_{0.5}TiO_3$, LLTO)를 고체전해질로 선정하여 다양한 환경에서 화학적 안정성에 관해 연구하였다. LLTO와 각종 용액과의 화학적 안정성을 살펴보기 위해 고체전해질을 DI water, 1 M $LiPF_6$ Ethylene Carbonate (EC)-Dimethyl Carbonate (DMC) (50:50 vol.%), 0.57 M LiOH (pH=13), 0.1 M HCl (pH=1)에 immersion하고 무게, 표면형상, 상(phase), 이온전도도 등의 변화를 관찰하였다. 또한 LLTO와 전극간의 반응성을 알아보기 위해 LLTO 분말과 음극물질인 $Li_4Ti_5O_{12}$ 및 양극물질인 $LiCoO_2$ 분말을 혼합한 후 $300^{\circ}C{\sim}700^{\circ}C$의 온도범위에서 열처리하여 반응을 가속화 한 후 상변화 현상을 살펴보았다.

• Proceedings of the Korean Society of Rural Planning Conference
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• 1996.03a
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• pp.17-20
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• 1996

지난 20여년 동안 급격한 도시화, 산업화를 추진하는 과정에서 대기와 물의 오염, 쓰레기 공해 등 자연환경의 훼손과 피폐화가 심각한 상태에 이르렀다. 또한, 과다한 농약. 비료의 투입과 농사료에 의한 축산으로 높은 농업 생산성을 이룩하였으나, 이로 인하여 토양오염과 하천과 지하수 수질오염, 식생, 곤충 등 생태계 파괴 등의 문제가 대두되고 있다. 최근, 수자원 함양, 수질 정화 등의 순기능으로 농업의 환경 기여 효과가 큰 것으로 발표되었다. 논으로 부터의 오염부하는 생활 오수나 공장폐수 등에 비하여 정성적으로는 미미한 것이 사실이며, 실제로 관개수로 유입되는 영양물질이 작물에 의하여 흡수되므로 물질 수지적 측면에서 수질정화 효과를 나타낸다는 개념이다. 그러나, 오염된 관개수와 함께 유입되는 물질과 영농 목적으로 투입되는 다량의 비료와 농약, 제초제 등의 독성 물질 등에 의한 생태 환경의 변화 등에 대한 영향 등에 관한 종합적 관점에서의 효과는 불분명한 것이 현실이다. 특히, 폭우시 농경지로부터 유출에 의한 토사유실과 영양 물질이 손실 등에 대한 정량적 평가가 부족하며, 이로 인한 유역에서의 수문, 수질, 생태환경 등을 정량적 분석이 부족한 것이 현실이다. 따라서, 농업유역에서의 수문과 물질순환과정을 정량적으로 분석하고, 이를 통하여 주요 오염원을 파악하고, 효과적인 조절방법 등을 위한 유역수질관리 기술개발과 함께, 경지와 주변 생태계에 미치는 영향 등을 극소화할 수 있는 종합적인 연구가 필요하다. 특히, 관개시설 등 농업기반조성사업에 따른 인위적인 수문환경으로 인한 농경지내에서의 수문.물질순환 기작의 변화 등을 고려한 수질 및 생태환경에 판한 종합적인 모니터링, 모델링 등의 접근이 필요한 것이다. 본 논문에서는 $.$95 농림수산특정연구 중 첨단연구과제로 추진 중인 농업생태환경 및 종합적 환경관리 시스템 개발연구의 목표와 내용, 범위 등을 소개하고, 농촌지역에서의 건전한 환경관리를 위한 유역관리기술 개발의 방향 등을 정리하도록 한다.

• Applied Microscopy
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• v.47 no.2
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• pp.63-69
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• 2017

Golgi staining has been modified and developed since Camillo Golgi introduced the black reaction in 1873. This study focuses on the commonly used Golgi staining methods and presents comprehensive data regarding three Golgi staining methods along with their strong and weak points. The Golgi-Cox method uses mercuric chloride for brain tissue impregnation and is a reliable technique for analyzing the complete dendritic tree of cortical neurons. However, specimens tend to shrink during the staining steps. Recent combination of the Golgi-Cox method and immunofluorescence provides additional options for neuroscientists. Rapid Golgi staining requires osmium tetroxide for the post-fixation process. It homogenously stains whole structures of neurons and provides their detailed anatomical morphology. This staining is influenced by the age of the specimen, temperature of the laboratory, and duration of each procedure. The Golgi-Kopsch method uses formaldehyde and glutaraldehyde instead of osmium tetroxide and can be used regardless of the age of the specimen and the duration after fixation. This method is suitable for research using human brain fixed for a long time or for specimens obtained from old-aged animals. Selecting a Golgi staining protocol that is appropriate for the specimen type and research purpose is important to achieve best results.

• Natural Product Sciences
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• v.20 no.2
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• pp.113-118
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• 2014

Ribes fasciculatum which belongs to Saxifragaceae has been widely used as a traditional medicine for the treatment of symptoms associated with lacquer poison. However, pharmacological studies on the R. fasciculatum are extremely limited until now. Thus, in this study, we evaluated the possible anti-inflammatory effects of ethyl acetate fraction of R. fasciculatum (ERF) using IFN-${\gamma}$/LPS-stimulated peritoneal macrophage model. We investigated the change in nitrite level in the absence or presence of ERF after LPS stimulation, and we found that ERF effectively attenuates the NO production in a dose dependent manner without notable toxicity. To determine the mechanism of the inhibitory action of ERF on NO production, we performed iNOS enzyme activity assay and Western blotting. Here we showed that both of iNOS enzyme activities and iNOS expressions were significantly down-regulated by ERF, indicating that these dual activities of ERF are responsible for ERF-mediated NO suppression. In addition, ERF inhibitied the expression of cyclooxygenase-2 (COX-2), an another key enzyme in inflammation through suppression of NF-${\kappa}B$ activation. We also tested anti-inflammatory properties of ERF not only in vitro, but in vivo using trypsin-induced paw edema model in mice. Our results revealed that the increased paw volume in response to trypsin injection was recovered by ERF supplement dose dependently.

• Health Policy and Management
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• v.23 no.4
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• pp.427-433
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• 2013

Background: This study was conducted to evaluate the factors affecting adherence in patients with hypertension and type 2 diabetes mellitus before and after a clinic based patient incentive program in Incheon. Methods: An observational follow-up study was done for 28,355 patients in one registered group and 245,598 patients in a non-registered group from March 16th 2009 to December 31th 2010 in Incheon. The registration, mandatory laboratory tests and number of clinic visits were collected by merging the Incheon Chronic Disease Management System data and the National Health Insurance Corporation (NHIC) data. As a measure of patient adherence, we used a variable of prescription days from the NHIC and defined above 80% of average prescription days as an appropriate patient adherence. Repeated measures analysis of variance and logistic regression were used to analyze the differences in patient adherence and factors affecting adherence. Results: The changes in prescription days for the registered group are larger than for the non-registered group. In the logistic regression model, including the variables with sex, age, income status and number of clinic visits, the registered group exhibited a higher Odds ratio in the patient adherence. Conclusion: This study revealed the association between registration and appropriate patient adherence in patients with hypertension or type 2 diabetes mellitus.

• Natural Product Sciences
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• v.22 no.3
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• pp.201-208
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• 2016

Here in this study, we investigated the lifespan-extending effect and underlying mechanism of methanolic extract of Moringa olelifa leaves (MML) using Caenorhabditis elegans (C. elegans) model system. To define the longevity properties of MML we conducted lifespan assay and MML showed significant increase in lifespan under normal culture condition. In addition, MML elevated stress tolerance of C. elegans to endure against thermal, oxidative and osmotic stress conditions. Our data also revealed that increased activities of antioxidant enzymes and expressions of stress resistance proteins were attributed to MML-mediated enhanced stress resistance. We further investigated the involvement of MML on the aging-related factors such as growth, food intake, fertility, and motility. Interestingly, MML significantly reduced growth and egg-laying, suggesting these factors were closely linked with MML-mediated longevity. We also observed the movement of aged worms to estimate the effects of MML on the health span. Herein, MML efficiently elevated motility of aged worms, indicating MML may affect health span as well as lifespan. Our genetic analysis using knockout mutants showed that lifespan-extension activity of MML was interconnected with several genes such as skn-1, sir-2.1, daf-2, age-1 and daf-16. Based on these results, we could conclude that MML prolongs the lifespan of worms via activation of SKN-1 and SIR-2.1 and inhibition of insulin/IGF pathway, followed by DAF-16 activation.