• 천문학회보
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• 제42권1호
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• pp.28.1-28.1
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• 2017

To investigate AGN outflows as a tracer of AGN feedback on the host galaxies, we perform integral-field spectroscopy of 20 type 2 AGNs at z<0.1 using the Magellan/IMACS and the VLT/VIMOS. The observed objects are luminous AGNs with the [O III] luminosity >$10^{41.5}erg/s$, and exhibit strong outflow signatures in the [O III] kinematics. We obtain the maps of the narrow and broad components of [O III] and $H{\alpha}$ lines by decomposing the emission-line profile. The broad components in both [O III] and $H{\alpha}$ represent the non-gravitational kinematics, (i.e., gas outflows), while the narrow components represent the gravitational kinematics (i.e., rotational disks), especially in $H{\alpha}$. By using the spatially integrated spectra within the flux-weighted size of the narrow-line region, we estimate the outflow energetics. The ionized gas mass is $(1.0-38.5){\times}10^5M_{\odot}$, and the mean mass outflow rate is $4.6{\pm}4.3M_{\odot}/yr$, which is a factor of ~260 higher than the mean mass accretion rate $0.02{\pm}0.01M_{\odot}/yr$. The mean energy injection rate is $0.8{\pm}0.6%$ of the AGN bolometric luminosity Lbol, while the mean momentum flux is $(5.4{\pm}3.6){\times}L_{bol}/c$, except for two most kinematically energetic AGNs. The estimated energetics are consistent with the expectations for energy-conserving outflows from AGNs, yet we do not find any supporting evidence of instantaneous star-formation quenching due to the outflows.

• 천문학회지
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• 제50권6호
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• pp.157-165
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• 2017

$H_2O$ maser emission at 22 GHz in the circumstellar envelope is one of the good tracers of detailed physics and kinematics in the mass loss process of asymptotic giant branch stars. Long-term monitoring of an $H_2O$ maser spectrum with high time resolution enables us to clarify acceleration processes of the expanding shell in the stellar atmosphere. We monitored the $H_2O$ maser emission of the semi-regular variable R Crt with the Kagoshima 6-m telescope, and obtained a large data set of over 180 maser spectra over a period of 1.3 years with an observational span of a few days. Using an automatic peak detection method based on least-squares fitting, we exhaustively detected peaks as significant velocity components with the radial velocity on a $0.1kms^{-1}$ scale. This analysis result shows that the radial velocity of red-shifted and blue-shifted components exhibits a change between acceleration and deceleration on the time scale of a few hundred days. These velocity variations are likely to correlate with intensity variations, in particular during flaring state of $H_2O$ masers. It seems reasonable to consider that the velocity variation of the maser source is caused by shock propagation in the envelope due to stellar pulsation. However, it is difficult to explain the relationship between the velocity variation and the intensity variation only from shock propagation effects. We found that a time delay of the integrated maser intensity with respect to the optical light curve is about 150 days.

• 한국ITS학회 논문지
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• 제10권5호
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• pp.135-145
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• 2011

ITS 기반기술 분야인 통신기술이 DSRC, CDMA, 무선랜(Wireless LAN) 등으로 다양화됨에 따라 ITS 서비스의 종류 및 기능도 점차 확대될 것으로 예상되고 있다. 이에 다양한 ITS 서비스를 제공받기 위해 ITS 서비스 제공에 사용되고 있는 여러 통신기술이 하나의 통합단말기에서 운영될 수 있도록 지원할 수 있는 표준플랫폼에 대한 연구 및 개발이 진행되고 있고 최근 표준플랫폼 OBU(On Board Unit)이 최근 제작과 시현도 하였다. 하지만 개발된 표준플랫폼 OBU(On Board Unit)의 표준적합성에 대한 확인이 반드시 필요하며 이에 실제 ITS 시스템에서 효율적으로 동작되는 것을 보증하고 표준기술의 활용성을 높이기 위해서는 표준기술을 구현하여 충분한 기능 및 운영테스트를 거칠 필요가 있다. 이에 본 논문에서는 개발된 표준플랫폼 OBU(On Board Unit)의 표준적용을 위해 시험도로를 구성하고 테스트하였다.

• 대한전자공학회논문지TE
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• 제37권2호
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• pp.83-90
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• 2000

본 논문에서는 IMT2000 중계기용으로 1.88-1.98 ㎓ 대역 전력증폭기를 저 가격, 소형으로 개발하였다. 이 전력증폭기는 두 단으로 구성되어 있으며 초단은 P-HEMT (ATF-34143, 800 micron gate width, Agilent Technologies)를 사용하였으며, 종단은 GaAs FET(EFA240D-SOT89, 2400 micron gate width, Excelics Semiconductor)를 사용하였다. 개발된 전력 증폭기는 전체 주파수 대역인 1880-1980 ㎒에서 이득이 29.5㏈, 1㏈ gain compression point는 29.5dBm, 3rd order intercept point(OIP3)는 42dBm 그리고 입출력 return loss는 -10㏈/-l2㏈ 이다. 본 연구에서는 이 전력 증폭기를 설계하기 위하여 각 소자의 비선형 모델을 사용하여 전력증폭기의 여러 가지 비선형 특성을 설계할 수 있었으며, 이 전력 증폭기의 크기는 42(L) x 34(W) mm으로 소형화가 가능하였다.

• 대한전자공학회논문지SD
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• 제47권1호
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• pp.94-101
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• 2010

최근 여러 개의 프로세서 및 메모리를 한 개의 칩에 구현하여 다양한 알고리즘을 구현하는 Multi-Processor System-on-Chip (MPSoC) 설계가 가능해지면서, 프로세서 간 interconnection을 최적화 하는 문제가 중요해졌다. Application에 따라서 최적 interconnection이 다르기 때문에, 체계적으로 다양한 사양에 적합한 interconnection 구조를 설계하는 방법이 필요하다. 본 논문에서는 프로세서가 4~16개 정도인 MPSoC application에서는 버스 구조가 적절한 점에 주목하여, 간단한 arbitration이 특징인 Single Arbitration Multiple Bus Accesses (SAMBA) 형 버스 구조를 이용하여, 다양한 application에 대한 성능 제약 조건을 만족하는 저비용 버스 구조를 찾는 새로운 방법을 제안하였다. 다양한 Application을 실험에 이용하여, 제안한 방법으로 성능 제약 조건 내에서 저비용 버스 구조를 찾았다. 같은 성능으로 최적화 전의 구조에 비해서 버스 분할에 필요한 로직 사용이 경우에 따라 약 50% 이상 감소한다. 또한 다양한 성능 조건에 대한 저비용 버스 구조를 찾을 수 있었다.

• 한국간호교육학회지
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• 제3권
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• pp.46-58
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• 1997

This review article provides the trend of current nursing curriculum of todays in Korea and its perspectives. This article reviewed 5 aspects of the current nursing curriculum for the undergraduate program, those are the (1)educational philosophy and believes (2)the nursing concepts revealed in the current nursing curriculum (3)the educational goals and objectives (4)the framework of nursing curriculum (5)the syllabus and credit hours. The common nursing concepts in the current nursing curriculum are Nursing, Human being, Environment/society, Health, Nursing science. The examplary vertical concepts composing of the current nursing curriculum are nursing process, life styles and the horizontal concepts are client, health promotion /recovery /maintenance, leadership, and research. The common subjects composing of the nursing syllabus are the introductory subjects(nursing history, nursing professionalism, foundamental nursing), and the supportive subjects (communication, human relationship, human growth and development, health education, etc) and nursing research, the intrductory basic sciences (anatomy, physiology etc.), and the major nursing subjects (adult nursing, child nursing, maternity nursing, psychiatric nursng, community nursing, nursing administration.) In order to have more advanced nursing education, the suggestions were provided as follows : (1) It is necessary to have revision and evaluation of the process and the structure of the current nursing curriculum periodically. (2) The concept of health promotion for all human being should be integrated into the nursing curriculum. (3) The nursing education program should be unified into baccalauliate level to get one type of nurse-registration system. (4) The nursing courses will need to provide the necessary contemporary Informations to allow the nurses to fuction efficiently in this rapidly changing era. (5) The use of new technology in nursing education is necessary to expand nursing education more.

• Earthquakes and Structures
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• 제11권6호
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• pp.1001-1025
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• 2016

Building structures generally have inherent low damping capability and hence are vulnerable to seismic excitations. Control devices therefore play a useful role in providing safety to building structures subject to seismic events. In recent years semi-active dampers have gained considerable attention as structural control devices in the building construction industry. Magneto-rheological (MR) damper, a type of semi-active damper has proven to be effective in seismic mitigation of building structures. MR dampers contain a controllable MR fluid whose rheological properties vary rapidly with the applied magnetic field. Although some research has been carried out on the use of MR dampers in building structures, optimal design of MR damper and combined use of MR and passive dampers for real scale buildings has hardly been investigated. This paper investigates the use of MR dampers and incorporating MR-passive damper combinations in building structures in order to achieve acceptable levels of seismic performance. In order to do so, it first develops the MR damper model by integrating control algorithms commonly used in MR damper modelling. The developed MR damper is then integrated in to the seismically excited structure as a time domain function. Linear and nonlinear structure models are evaluated in real time scenarios. Analyses are conducted to investigate the influence of location and number of devices on the seismic performance of the building structure. The findings of this paper provide information towards the design and construction of earthquake safe buildings with optimally employed MR dampers and MR-passive damper combinations.

• Advances in Computational Design
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• 제5권2호
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• pp.127-146
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• 2020

Building Information Modeling (BIM) is increasingly used throughout the facility's life cycle for various applications, such as design, construction, facility management, and maintenance. For existing buildings, the geometry of as-built BIM is often constructed using dense, three dimensional (3D) point clouds data obtained with laser scanners. Traditionally, as-built BIM systems do not contain the material and textural information of the buildings' elements. This paper presents a semi-automatic method for generation of material and texture rich as-built BIM. The method captures and integrates material and textural information of building elements into as-built BIM using thermal infrared sensing (TIS). The proposed method uses TIS to capture thermal images of the interior walls of an existing building. These images are then processed to extract the interior walls using a segmentation algorithm. The digital numbers in the resulted images are then transformed into radiance values that represent the emitted thermal infrared radiation. Machine learning techniques are then applied to build a correlation between the radiance values and the material type in each image. The radiance values were used to extract textural information from the images. The extracted textural and material information are then robustly integrated into the as-built BIM providing the data needed for the assessment of building conditions in general including energy efficiency, among others.

• 대기
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• 제27권1호
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• pp.105-118
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• 2017

This study assesses the performance of the Weather Research and Forecasting (WRF) model in reproducing regional climate over CORDEX-East Asia Phase 2 domain with different cumulus parameterization schemes [Kain-Fritch (KF), Betts-Miller-Janjic (BM), and Grell-Devenyi-Ensemble (GD)]. The model is integrated for 27 months from January 1979 to March 1981 and the initial and boundary conditions are derived from European Centre for Medium-Range Weather Forecast Interim Reanalysis (ERA-Interim). The WRF model reasonably reproduces the temperature and precipitation characteristics over East Asia, but the regional scale responses are very sensitive to cumulus parameterization schemes. In terms of mean bias, WRF model with BM scheme shows the best performance in terms of summer/winter mean precipitation as well as summer mean temperature throughout the North East Asia. In contrast, the seasonal mean precipitation is generally overestimated (underestimated) by KF (GD) scheme. In addition, the seasonal variation of the temperature and precipitation is well simulated by WRF model, but with an overestimation in summer precipitation derived from KF experiment and with an underestimation in wet season precipitation from BM and GD schemes. Also, the frequency distribution of daily precipitation derived from KF and BM experiments (GD experiment) is well reproduced, except for the overestimation (underestimation) in the intensity range above (less) then $2.5mm\;d^{-1}$. In the case of the amount of daily precipitation, all experiments tend to underestimate (overestimate) the amount of daily precipitation in the low-intensity range < $4mm\;d^{-1}$ (high-intensity range > $12mm\;d^{-1}$). This type of error is largest in the KF experiment.

• Journal of Nutrition and Health
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• 제25권7호
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• pp.668-683
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• 1992

To evaluate the current practices of the tube feeding and the status of tube feeding patient 76 adult in-patients at 6 hospitals located in Seoul and Chung-buk province were examined through reviewing patient charts observing patients and interviewing patients nurses dietitians patients' family or care-givers. The results were as follows : 1) An average age of the patients was 54.5 years with 41% over 60 years old. Patients with decreased mental status dysphagia esophageal obstruction and respiratory problem were fed by tubes. 2) The range of duration of tube feeding is between 4 days and 6 years. Most patients were received formula through nasogastric tube(89.5%) while 7.9% of gastrostomy and 2.6% of jejunostomy. Administration method for formula were bolus feeding regardless of the route of formula delivery. 3) Mean total calories received for men were 1590 kcal and 1450 kcal for female. Mean volume per meal was 282m, l and mean frequency of feeding was 5.68 while mean feeding interval 3$\frac{1}{4}$ hours and mean rate of infusion 68.4ml/min. All patients received hospital-blenderi-zed formula as the major source of nutrition. Home-blenderized formula and commercial formula as a supplement were used 35%, 13.2% respectively. 4) Thirty-eight percent of patients was hypoalbuminemia and 61% was at the moderate level of deficiency in hemoglobin. 5) Complications associated with tube feeding were diarrhea (22.4%) constipation(21.1%) vomiting(11.8%) and so on. 6) Serum albumin levels of patients who have complications associated with tube feeding were significantly lower than those of patients without complications In planning a tube feeding regimen the type of a formula must be integrated with both a delivery system and a protocol for administering the tube feeding. the multidisciplinary effort required to deliver enteral therapy is essential to improve current practices used at hospitals.