• 임상간호연구
• /
• 제17권3호
• /
• pp.443-454
• /
• 2011

Purpose: The purpose of this study was to investigate the predictors of delirium in patients after orthopedic surgery. Methods: Participants were 121 orthopedic surgery patients from one university affiliated hospital located in Seoul. The instrument of Delirium Observation Screening Scale (DOS) developed by Schuurmans et al. (2003) was utilized. Data were collected from September 1st, 2010 to March 31st, 2011 and analyzed using SPSS 12.0 with descriptive statistics, t-test, chi-square test and logistic regression. Results: The delirium in patients after orthopedic surgery was occurred in 9 (7.4%) out of 121 patients. Several factors were associated with the delirium occurrence age, admission route, preadmission Activity of Daily Living (ADL), preadmission hearing aid use, preadmission walking degree, diagnosis, type of surgery, Intensive Care Unit (ICU) stay after surgery, restraint, drainage tube, time of admission to surgery, preoperative albumin and preoperative sodium. Preadmission ADL, preoperative sodium and time of admission to surgery were the significant predictors of the delirium occurrence. Conclusion: Study results may help nurses predicting and detecting delirium early and providing preventive measures to the patients with high risk of delirium after orthopedic surgery.

• 한국측량학회지
• /
• 제39권5호
• /
• pp.329-341
• /
• 2021

This study derives the risk-Influence factors for subway structures, the basis for the transition from the current subway disaster recovery-oriented maintenance system to a preemptive disaster management system, to reduce risk factors for existing subway structures. To apply reasonable risk assessment techniques, risk influence factors for subway underground structures using statistical information(spatial information) and risk influence factors according to frequency of accidents were selected to derive the risk factors. The significant risk factors were verified through ground subsidence (SI: Subsidence Impact)-based correlation analysis. This process confirmed that the subsidence of the ground was a risk influence factor for the subway structure. The main result of this study is that derive the risk factors to improve the risk factors of subway structures due to the rapid increase in disaster risk factors. The derived risk factors that were expected to affect the depression around subway stations and track structures did not show a noticeable correlation, but the cause of this may be that there is no physical connection between them, but on the other hand, the accumulated data may not accurately record the surrounding depression. Accordingly, in order to evaluate the risk of depression around the station and track, more intensive observation and data accumulation around the structure are required.

• 아태비즈니스연구
• /
• 제11권4호
• /
• pp.21-36
• /
• 2020

Purpose - This study analyzes the effect of sellers' dishonesty on various market outcomes such as seller profit, buyer profit, and market welfare, through precisely measuring the level of sellers' information disclosure and its economic impacts. As an explicit observation of sellers' dishonesty is not easy in most other settings, this study is expected to suggest unique and meaningful implications on the effect of sellers' incomplete information disclosure to researchers, managers, and policy makers. Design/methodology/approach - In order to precisely measure the level of sellers' dishonesty under information asymmetry, this study analyzes the data from an incentive-based economic experiment using z-Tree software. This experimental method enables us to focus on the strategic interactions among participants, observe the integrity of seller's information disclosure, and reproduce real market situations. Findings - The analysis of sellers' dishonesty has provided the following important and counterintuitive findings about the reality of buyer-seller interactions under information asymmetry. First, sellers' lies do not affect seller profit even when they are very intensive. Second, sellers' dishonesty negatively affects buyer profit and the entire market welfare. Third, a seller's quality claim has a positive effect on the seller profit only when a seller is being honest. Research implications or Originality - This study analyzes sellers' dishonesty using incentive-based economic experiment using z-Tree software which provides a straightforward examination on dishonest behavior of sellers, that is not readily available with other types of observational or experimental data.

• 교육시설 논문지
• /
• 제26권3호
• /
• pp.33-41
• /
• 2019

As the information age matures, the learning style of youth is changing rapidly. Students study at a variety of places such as cafe or lobbies utilizing various digital learning devices. Along with the place changes, learning methods are also changing. Student-centered learning methods such as smart learning, collaborative learning, and activity-based learning are increasingly being utilized instead of the traditional instructor-centered learning in which knowledge is unilaterally delivered. Accordingly, many universities are remodeling central libraries, and they are also transforming lobby spaces of the college buildings into simple but useful learning spaces. In this study, we analyze the characteristics of learning spaces in universities from the standpoint of the students. According to the analysis, overall satisfaction is high in terms of comfortable physical learning environments such as Wi-Fi, furniture, lighting, etc. But the spaces are still optimized for individual and intensive learning. There seems to be a lack of effort to support collaborative learning or activity-based learning. This observation is confirmed by the characteristics of the central library, and it is considered that the reason why the college buildings are preferred by students is that college buildings are more suitable for collaborative or activity-based learning than libraries.

• 한국물환경학회지
• /
• 제35권2호
• /
• pp.131-144
• /
• 2019

Climate Change affects the hydrological cycle in agricultural watersheds through rising air temperature and changing rainfall patterns. Agricultural watersheds in Korea are characterized by extensive paddy fields and intensive water use, a resource that is under stress from the changing climate. This study analyzed the effects of climate change on river flows for Geum Cheon and Eun-San Choen watershed using STREAM, a semi-distributed watershed model. In order to evaluate the performance and improve the reliability of the model, calibration and validation of the model was done for one flow observation point and three reservoir water storage ratio points. Climate change scenarios were based on RCP data provided by the Korea Meteorological Administration (KMA) and bias corrections were done using the Quantile Mapping method to minimize the uncertainties in the results produced by the climate model to the local scale. Because of water mass-balance, evapotranspiration tended to increase steadily with an increase in air temperature, while the increase in RCP 8.5 scenario resulted in higher RCP 4.5 scenario. The increase in evapotranspiration led to a decrease in the river flow, particularly the decrease in the surface runoff. In the paddy agricultural watershed, irrigation water demand is expected to increase despite an increase in rainfall owing to the high evapotranspiration rates occasioned by climate change.

• 한국안전학회지
• /
• 제38권3호
• /
• pp.85-92
• /
• 2023

A safety helmet is considered the last gear to protect workers from harmful and dangerous events occurring on industrial sites. Recently, interest in the importance of personal protective equipment design reflecting individual characteristics has been emphasized to improve usability and convenience. However, it has been found that if it is inconvenient to wear or has poor work efficiency, it will not be used well or will be used incorrectly. In this study, an investigation was performed with 35 questions, direct observation, and intensive interviews of construction workers to determine the inconvenience and problems of wearing safety helmets. Moreover, managers of 9 construction sites in 6 cities were asked about the performance and design of safety helmets. As a positive answer, it was found that the brim (awning) of the safety helmet was shortened to give the safety glasses a light-shielding function. In addition, an upward adjustment all-in-one type safety helmet was requested. On the other hand, it was revealed that negative answers felt uncomfortable due to the brim (awning) on the front of the helmet. Based on the survey results, a new helmet model suitable for construction site activities was presented, and wearability improvement determinants were discovered through performance and design improvement.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
• /
• pp.376-379
• /
• 2006

A numerous oil slicks of natural origin were revealed in the southwest (SW) part of Caspian Sea by the synthetic aperture radar (SAR) images acquired by Envisat satellite in 2003-2004. On the basis of computer processing, visual analysis of SAR images and comparisons with bathymetry, geophysical and seismic data in geographic information system (GIS), a link between these slicks and unloading of liquid hydrocarbons in the SW Caspian is established. Oil slicks are basically concentrated above domes of local geological formations of the sedimentary cover. In total more than 90 seeps and mud volcanoes having a repeating regime and representing an active type were identified; they are distributed across the SW Azerbaijan and West Iranian sectors. Periodical occurrence of slicks can reflect alternation of mud volcanism pulses forced by intensive seismicity with the quiet periods. Seepage rate of oil in the SW part of the Caspian Sea according to SAR images is estimated to be up to 16,000 metric tons per year. The importance of unloading of oils on hydrochemistry and ecological conditions of the Caspian Sea is demonstrated. Conclusion is done that the Envisat SAR to be an excellent tool for studying oil seeps through observation oil slicks floating on the sea surface.

• 천문학회보
• /
• 제44권2호
• /
• pp.63.3-63.3
• /
• 2019

Nearby young moving groups (NYMGs hereafter) are gravitationally unbound loose young stellar associations located within 100 pc of the Sun. Since NYMGs are crucial laboratories for studying low-mass stars and planets, intensive searches for NYMG members have been performed. For identification of NYMG members, various strategies and methods have been applied. As a result, the reliability of the members in terms of membership is not uniform, which means that a careful membership re-assessment is required. In this study, I developed a NYMG membership probability calculation tool based on Bayesian inference (Bayesian Assessment of Moving Groups: BAMG). For the development of the BAMG tool, I constructed ellipsoidal models for nine NYMGs via iterative and self-consistent processes. Using BAMG, memberships of claimed members in the literature (N~2000) were evaluated, and 35 per cent of members were confirmed as bona fide members of NYMGs. Based on the deficiency of low-mass members appeared in mass function using these bona fide members, low mass members from Gaia DR2 are identified. About 2000 new M dwarf and brown dwarf candidate members were identified. Memberships of ~70 members with RV from Gaia were confirmed, and the additional ~20 members were confirmed via spectroscopic observation. Not relying on previous knowledge about the existence of nine NYMGs, unsupervised machine learning analyses were applied to NYMG members. K-means and Agglomerative Clustering algorithms result in similar trends of grouping. As a result, six previously known groups (TWA, beta-Pic, Carina, Argus, AB Doradus, and Volans-Carina) were rediscovered. Three the other known groups are recognized as well; however, they are combined into two new separate groups (ThOr+Columba and TucHor+Columba).

• 천문학회보
• /
• 제45권1호
• /
• pp.35.3-36
• /
• 2020

The Time Domain Field is one of the future GTO program fields of JWST(JWST/GTO TDS), surveying about 14' diameter field at the North Eliptical Pole(NEP) with NIRCam/NIRISS. As a part of the multi-wavelength study of the field, we have obtained SCUBA-2 850㎛ mapping which reaches a depth of σrms = 0.9mJy/beam and detect 93 sources at S/N > 3.5 ― which are expected to be highly star-forming (SFR>400M◉/yr) galaxies at z ≳ 1.5-4 and pinpoint the location at <0. " 1 accuracy of 68 sub-mm sources by identifying VLA 3GHz radio counterparts. In this talk, we will introduce the SCUBA-2 JWST/GTO TDS project and the newly discovered sub-mm sources in this field.

• 한국지구과학회지
• /
• 제33권2호
• /
• pp.148-161
• /
• 2012

2010년 8월 13일부터 9월 3일까지 수도권지역에서 집중관측(Predictability and Observation Experiment of Korea-2010, ProbeX-2010)이 수행되었으며, 그 일환으로 동두천, 인천공항, 양평에서 6시간 간격으로 라디오존데 관측이 실행되었다. 관측기간 동안 우리나라의 전형적인 호우 패턴인 스콜선형, 정체전선형, 태풍 전면 수렴형, 열대저압부형, 태풍 직접형 호우가 연속적으로 발생하였다. 8월 15일 03 KST 경에는 스콜선형 구름대가 수도권 지역에서 발달하였다. 따뜻하고 습한 하층 공기 위로 건조한 중층 공기가 유입되어 강한 대류 불안정이 형성되었으며 이로 인해 호우가 발생하였다. 8월 23일부터 26일, 8월 27일부터 29일은 각각 정체전선과 태풍 전면 수렴대의 영향을 받아 강우가 발생하였다. 정체전선형 강우 초기에는 열적 불안정이 우세하게 나타났으나 강우 후기에는 역학적 불안정이 강화되었다. 이 기간 중 특히 강한 강수는 서해상에서 남풍류 하층 제트가 발달한 8월 25일에 발생하였다. 태풍 전면 수렴형 강우기간에는 열적 불안정과 역학적 불안정이 모두 유지되는 특징을 보였다. 이 기간 중 특히 강한 강수는 높은 상당온위(>345 K)를 가진 열대 공기가 대기 중하층에 거쳐 유입되었을 때 발생하였다. 8월 27일과 9월 2일에는 각각 열대저압부와 태풍 곤파스의 영향에 의해 강우가 발생하였다. 이 사례들 동안에는 역학적 불안정이 매우 강하게 발달하였다.