• 한국환경과학회지
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• 제21권6호
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• pp.739-747
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• 2012

Due to the difficulties for measuring flood discharge in the dangerous field conditions, conventional instruments with relatively low accuracy such as float still have been widely utilized for the field survey. It is also limited to use simple stage-discharge relationship for assessment of the flood discharge, since the stage-discharge relationship during the flood becomes complicated loop shape. In recent years, various non-intrusive velocity measurement techniques such as electromagnetic wave or surface images have been developed, which is quite adequate for the flood discharge measurements. However, these new non-intrusive techniques have little tested in the flood condition, though they promised efficiency and accuracy. Throughout the field observations, we evaluated the validity of these techniques by comparing discharge and velocity measurements acquired concurrently during the flood in a mountain stream. As a result, the flood discharge measurements between electromagnetic wave and surface image processing techniques showed high positive relationship, but velocities did not matched very well particularly for the high current speed more 3 m/s. Therefore, it should be noted here that special cares are required when the velocity measurements by those two different techniques are used, for instance, for the validation of the numerical models. In addition, authors assured that, for the more accurate flood discharge measurements, velocity observation as well as stage height is strongly necessary owing that the unsteady flow occurs during the flood.

• 천문학회보
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• 제41권2호
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• pp.66.3-67
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• 2016

The Giant Magellan Telescope (GMT) will feature two interchangeable Gregorian secondary mirrors, an adaptive secondary mirror (ASM) and a fast-steering secondary mirror (FSM). The FSM has an effective diameter of 3.2 m and built as seven 1.1 m diameter circular segments, which are conjugated 1:1 to the seven 8.4m segments of the primary. Each FSM segment contains a tip-tilt capability for fine co-alignment of the telescope subapertures and fast guiding to attenuate telescope wind shake and mount control jitter. This tip-tilt capability thus enhances performance of the telescope in the seeing limited observation mode. As the first stage of the FSM development, KASI conducted a Phase 0 study to develop a program plan detailing the design and manufacturing process for the seven FSM segments. The GMTO-KASI team matured this plan via an internal review in May 2016 and the revised plan was further assessed by an external review in June 2016. In this poster, we present the technical aspects of the FSM development plan.

• 한국정보통신학회논문지
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• 제17권11호
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• pp.2745-2752
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• 2013

강우량을 측정하는데 있어서 전도형 및 중량형 강수량계가 전 세계적으로 오랫동안 사용되어 지고 있다. 그러나 종래의 강수량계는 관측오차와 자체 분해능의 한계로 인해 측정범위가 제한되는 문제가 있다. 본 논문에서 제안된 강수량계는 유량측정을 통해 강수량을 환산하는 원리를 최초로 적용하였으며, 개발된 모델을 국가공인교정기관(KOLAS)에서 표준교정시스템을 이용하여 실내실험을 실시하였다. 그 결과, 본 연구에서 개발된 강수량계는 실험조건에서 설정한 20~420 mm/H의 강우강도 구간에 걸쳐 ${\pm}2%$의 오차율을 나타냈고, 종래 대비 보다 정확하고 신뢰성 있는 측정이 가능함을 보였다.

• Journal of Communications and Networks
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• 제14권4호
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• pp.352-363
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• 2012

In this paper, we study the role of cooperative relays to provide and improve secure communication rates through decodeand-forward (DF) strategies in a full-duplex multiple relay network with an eavesdropper. We consider the DF scheme as a basis for cooperation and propose several strategies that implement different versions of this scheme suited for cooperation with multiple relays. Our goal is to give an efficient cooperation paradigm based on the DF scheme to provide and improve secrecy in a multiple relay network. We first study the DF strategy for secrecy in a single relay network. We propose a suboptimal DF with zero forcing (DF/ZF) strategy for which we obtain the optimal power control policy. Next, we consider the multiple relay problem. We propose three different strategies based on DF/ZF and obtain their achievable secrecy rates. The first strategy is a single hop strategy whereas the other two strategies are multiple hop strategies. In the first strategy, we show that it is possible to eliminate all the relays' signals from the eavesdropper's observation (full ZF), however, the achievable secrecy rate is limited by the worst source-relay channel. Our second strategy overcomes the drawback of the first strategy, however, with the disadvantage of enabling partial ZF only. Our third strategy provides a reasonable compromise between the first two strategies. That is, in this strategy, full ZF is possible and the rate achieved does not suffer from the drawback of the first strategy. We conclude our study by a set of numerical results to illustrate the performance of each of the proposed strategies in terms of the achievable rates in different practical scenarios.

• 대한소아치과학회지
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• 제33권4호
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• pp.704-709
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• 2006

이소맹출은 발육과정 중 그 발생지에서의 정상적 맹출 경로에서 벗어난 치아의 맹출을 의미한다. 이소맹출의 극단적인 형태로 전위가 있는데 이것은 두 치아의 위치가 서로 바뀐 것이다. 이러한 이소맹출 및 전위된 치아의 치료는 치아가 맹출되는 방향, 치근단의 완성정도, 맹출공간의 존재여부 등에 따라 단순한 관찰에서 외과적 노출 후 교정적 견인까지 매우 다양하며, 위치 이상이 심한 경우에는 외과적 자가이식이나 발치를 고려할 수 있다. 이중 자가치아이식은 치아를 구강내의 한 위치에서 다른 발치와나 외과적으로 형성된 치조와로 이동시키는 술식으로, 치아가 교정력을 가할 수 없는 위치에 존재하거나 치아 이동에 제한이 있어 통상적인 치료가 불가능할 경우 발거에 앞서 고려할 수 있는 술식이다. 본 증례들은 교정적 견인 및 배열이 어렵다고 판단되는 이소맹출하는 상악 측절치와 상악 견치를 자가이식함으로써 심미적, 기능적으로 양호한 결과를 얻을 수 있었다.

• 중환자간호학회지
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• 제13권1호
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• pp.44-62
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• 2020

Purpose : The purpose of this study was to systematically review the measurement tools that are used to assess the pain of intensive care unit (ICU) patients. Method : In this systematic review, the studies published between 2009 and 2018 were selected based on the PRISMA flow chart. Data sources included MEDLINE, EMBASE, CINAHL, and Cochran. We assessed the quality of pain assessment tools reported in individual studies using Terwee et al.'s the Quality Criteria for Measurement Properties. Results : We reviewed 67 studies and 12 pain assessment tools that included two self-reported, seven observational, and three multifaced tools with observations and physiological indicators. The most frequently used tool was the Critical Care Pain Observation Tool. The Multidimensional Observational Pain Assessment Tool was rated the highest quality. Nine of the ten tools that included observations reported content validity, four reported construct validity and nine reported correlation coefficient. Conclusion : It was found that observational tools are appropriate for assessing pain in ICU patients with limited communication skills. To increase the validity and reliability of pain assessment in ICU patients, further research on the physiological indicators of pain is needed.

• 대한한의학방제학회지
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• 제21권1호
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• pp.186-199
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• 2013

Objectives : The objectives of this study was to obtain acute information (single oral dose toxicity) of Red-Koji (Monascus purpureus 12002) Fermented Scutellariae Radix Aqueous Extracts (fSR), has been traditionally used in Korean medicine for treating various diseases including inflammatory diseases. Methods : In order to observe the 50% lethal dose (LD50), approximate lethal dosage (ALD) and target organs, fSR powders were once orally administered to female and male ICR mice at dose levels of 2,000, 1,000, 500 and 0 (control) mg/kg (body weight.). The mortality and changes on body weight, clinical signs and gross observation were monitored during 14days after single oral treatment of fSR with organ weights and histopathological observations of 12 types of principle organs. Results : After single oral treatment of fSR, we could not find any mortality and toxicological evidences up to 2,000 mg/kg treated group, the limited dosages in rodents, on the body and organ weights, clinical signs, gross and histopathological observations, except for some accidental findings. Conclusions : The results obtained in this study suggest that the LD50 and ALD of fSR in both female and male mice after single oral treatment were considered as over 2,000 mg/kg because no mortalities were detected up to 2,000 mg/kg and can be safety used in clinics.

• 대기
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• 제22권2호
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• pp.233-243
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• 2012

The Barnes scheme is used in Digital Forecast System (DFS) of the Korea Meteorological Administration (KMA) for real-time analysis. This scheme is an objective analysis scheme with a distance-dependent weighted average. It has been widely used for mesoscale analyses in limited geographic areas. The isotropic Gaussian weight function with a constant effective radius might not be suitable for certain conditions. In particular, the analysis error can be increased for stations located near mountains. The terrain of South Korea is covered with mountains and wide plains that are between successive mountain ranges. Thus, it is needed to consider the terrain effect with the information of elevations for each station. In order to improve the accuracy of the temperature objective analysis, we modified the weight function which is dependent on a distance and elevation in the Barnes scheme. We compared the results from the Barnes scheme used in the DFS (referred to CTL) with the new scheme (referred to EXP) during a year of 2009 in this study. The analysis error of the temperature field was verified by the root-mean-square-error (RMSE), mean error (ME), and Priestley skill score (PSS) at the DFS observation stations which is not used in objective analysis. The verification result shows that the RMSE and ME values are 1.68 and -0.41 in CTL and 1.42 and -0.16 in EXP, respectively. In aspect of spatial verification, we found that the RSME and ME values of EXP decreased in the vicinity of Jirisan (Mt. Jiri) and Taebaek Mountains. This indicates that the new scheme performed better in temperature verification during the year 2009 than the previous scheme.

• 대기
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• 제26권3호
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• pp.401-412
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• 2016

A 3D sonic anemometer has been installed at Yongpyong alpine slope since Oct. 23th 2014 to observe the slope winds and to analyze turbulent characteristics with the change in surface cover (grass and snow) and the synoptic wind strength. Eddy covariance method has been applied to calculate the turbulent quantity after coordinate transformation of a planar-fit rotation. We have carefully selected 3 good episodes in the winter season (23 October 2014 to 28 February 2015) for each category (9 days in total), such as grass and snow covers in case of weak synoptic wind condition, and grass cover of strong synoptic wind. The diurnal variations of the slope winds were well developed like the upslope wind in the daytime and downslope wind in the nighttime for both surface covers (grass and snow) in the weak synoptic forcing, when accordingly both heat and momentum fluxes significantly increased in the daytime and decreased in the nighttime. Meanwhile, diurnal variation of heat flux was not present on the snow cover probably in associated with significant fraction of sunlight reflection due to high albedo especially during the daytime in comparison to those on the grass cover. In the strong synoptic regime, the most dominant feature at Yongpyong, only the southeasterly downslope winds were steadily generated irrespective of day and night with significant increases in momentum flux and turbulent kinetic energy as well, which could suggest that local circulations are suppressed by the synoptic scale forcing. In spite of only one season analysis applied to the limited domain, this kind of an observation-based study will provide the basis for understanding of the local wind circulation in the complex mountain domain such as Gangwon in Korea.

• 동의생리병리학회지
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• 제23권5호
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• pp.1145-1153
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• 2009

The object of this study was to obtain acute information single oral dose toxicity of Mahwangbujaseshin-tang extracts, with mouse bone marrow cell micronucleus test for detecting possible genotoxicity. In order to observe the 50% lethal dose, approximate lethal dosage, maximum tolerance dosage and target organs, test articles were once orally administered to ICR mice at dose levels of 2000, 1000, 50 mg/kg according to the recommendation of KFDA Guidelines. The mortality and changes on body weight, clinical signs and gross observation were monitored during 14 days after dosing according to KFDA Guidelines with organ weights of 12 types of principle organs. In addition, after twice oral treatment of Mahwangbujaseshin-tang extracts 2000, 1000 and 500 mg/kg, we checked the changes on the number of MNPCE. We could not find any mortality, clinical signs, changes in the body weight and gross findings upto 2000 mg/kg treated group. The limited dosages in rodents except for increases of lymphoid organ weights and hypertrophy encounted as results from pharmacological effects of Mahwangbujaseshin-tang extracts, immune modulator effects with some sporadic accidental findings not toxicological signs. No evidence of increases of MNPCE numbers were also detected in all three different dosages of Mahwangbujaseshin-tang extracts treated mice. The results obtained in this study suggest that the LD50 and ALD of Mahwangbujaseshin-tang extracts in mice were considered as over 2000 mg/kg because no mortalities were detected upto 2000 mg/kg that was the highest dose recommended by KFDA and OECD. And the results of mouse bone marrow micronucleus test of Mahwangbujaseshin-tang extracts is negative results.