• Title/Summary/Keyword: Critical period

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STELLAR MAGNETIC ACTIVITY AND LONG TERM LUMINOSITY VARIATIONS OF LATE TYPE STARS.: II. STELLAR ACTIVITY PERIODS BASED ON PARKER'S DYNAMO THEORY

  • Park, Chang-Bum;Yun, Hong-Sik
    • Journal of The Korean Astronomical Society
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    • v.19 no.2
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    • pp.91-107
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    • 1986
  • Making use of our extended version of $\ddot{O}pik's$ convection theory, we have calculated magnetic cycle periods of the sun and late type stars by using Parker's dynamo theory, where we have included the non-linear effect. We presented a relationship between the computed cycle period and spectral type to analyze observed magnetic activities of the late type stars and long-term luminosity variations. It is found that (1) the stellar magentic-cycle period increases towards the later spectral type, (2) the rapid rotation facilitates the activity-related luminosity variation of stars later than about K5, (3) differential rotation plays a critical role in determining the magnetic activity-cycle period, and (4) the non-local effect should be taken into account in order to understand the observed long-term luminosity variations.

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Impact of uncertain natural vibration period on quantile of seismic demand

  • Hong, H.P.;Wang, S.S.;Kwan, A.K.H.
    • Structural Engineering and Mechanics
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    • v.28 no.4
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    • pp.357-372
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    • 2008
  • This study investigates effect of uncertainty in natural vibration period on the seismic demand. It is shown that since this uncertainty affects the acceleration and displacement responses differently, two ratios, one relating peak acceleration responses and the other relating the peak displacement responses, are not equal and both must be employed in evaluating and defining the critical seismic demand. The evaluation of the ratios is carried out using more than 200 strong ground motion records. The results suggest that the uncertainty in the natural vibration period impacts significantly the statistics of the ratios relating the peak responses. By using the statistics of the ratios, a procedure and sets of empirical equations are developed for estimating the probability consistent seismic demand for both linear and nonlinear systems.

The Effects of Simulation Training for New Graduate Critical Care Nurses on Knowledge, Self-efficacy, and Performance Ability of Emergency Situations at Intensive Care Unit (시뮬레이션 교육이 중환자실 신규간호사의 응급상황 관련 지식과 자기효능감 및 수행능력에 미치는 효과)

  • Chang, Sun-Ju;Kwon, Eun-Ok;Kwon, Young-Ok;Kwon, Hee-Kyoung
    • Korean Journal of Adult Nursing
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    • v.22 no.4
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    • pp.375-383
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    • 2010
  • Purpose: The purpose of this study was to examine if simulation training affects new graduate critical care nurses' knowledge, self-efficacy, and performance ability in emergency situations. Methods: Forty new graduate critical care nurses were randomly assigned to either an experimental or a control group. The experimental group had didactic with simulation. The control group received only didactic without simulation about emergency situations. The data were collected before and after the training interventions. An independent t-test used for difference among variables. Results: There were no significant demographic differences between the two groups or any differences on data collected knowledge, self-efficacy and performance ability. Following the training, there were significant performance ability scores (p<.001) among the nurses receiving didactic with simulation. There were no significant difference between the two groups relative to knowledge scores (p=.117), or the self-efficacy scores (p=.100). Conclusion: This study showed that simulation training for new graduate critical care nurses is useful to improve performance ability on emergency situations. Hence, providing simulation training to critical care nurses during an orientation period would improve quality of critical care nursing and help the new graduates nurse's adaptation.

A Case of Diffuse Alveolar Hemorrhage with Glomerulonephritis after Propylthiouracil Treatment (Propylthiouracil 복용 후 발생한 사구체신염이 동반된 미만성 폐출혈 1예)

  • Lee, Ji-Hyun;Kim, Min-Su;Lee, Jae-Gon;Kim, Dae-Sik;Yang, Hae-Jin;Kang, Kyung-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.72 no.1
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    • pp.93-97
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    • 2012
  • Propylthiouracil (PTU) is one of the most common drugs used in the treatment of Graves' disease. There are a number of side effects found with PTU use including fever, rash, arthralgia, and flu-like symptoms. Recently antineutrophil cytoplasmic antibodies (ANCA) positive vasculitis after PTU treatment was reported as a rare side effect, which can cause diffuse alveolar hemorrhage and glomerulonephritis. A 45-year-old woman with Graves' disease had been treated with PTU for five months, complained of hemoptysis due to pulmonary alveolar hemorrhage causing anemia, and also had hematuria. Simple chest X-ray and HRCT showed bilateral consolidation and bronchoalveolar lavage fluid revealed alveolar hemorrhage. A serologic test was positive for ANCA against myeloperoxidase and proteinase-3. Such findings suggested that the presence of PTU induced ANCA positive vasculitis. Cessation of PTU and the administration of high dose steroids improved the clinical manifestation, radiologic and serologic findings. We observed ANCA titer serially for 6 years. During the follow up period, ANCA titer decreased slowly and stayed within the acceptable upper normal limit.

The Effect of Simulation Integrated with Problem Based Learning(S-PBL) on Self-leadership, Critical Thinking Disposition, Goal Commitment (PBL기반 시뮬레이션 융합교육이 간호대학생의 셀프리더십, 비판적 사고성향, 목표몰입에 미치는 효과)

  • Kwon, Soon-Jo
    • Journal of the Korea Convergence Society
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    • v.11 no.12
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    • pp.373-381
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    • 2020
  • The purpose of this study was performed to examine the effects of simulation integrated with problem based learning(S-PBL) on self-leadership, critical thinking disposition, goal commitment for nursing students. The design was a one group pre-post test. The subjects consisted of one group of 90 fourth year nursing students of K Colleage. The period for this study was from March to June in 2019. The collected data were analyzed by Paired t-test, Pearson correlation coefficient. This study showed significantly higher self-leadership(t=-16.22, p<.001), critical thinking disposition(t=-11.36, p<.001), goal commitment(t=-7.06, p<.001). There was a significant positive correlation between self-leadership and critical thinking disposition(r=.438, p<.001), self-leadership and goal commitment(r=.285, p<.001). In conclusion, this study show that integrated with problem based learning(S-PBL) can be used for improvement the self-leadership, critical thinking disposition, goal commitment. It is suggested to check the effect of simulation integrated with problem based learning applying various nursing situations in the future.

Effects of heat treatment temperature on the formation of MgB2 bulk superconductors prepared using MgB4 and Mg powder

  • Kim, S.H.;Kang, W.N.;Lee, Y.J.;Jun, B.H.;Kim, C.J.
    • Progress in Superconductivity and Cryogenics
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    • v.19 no.1
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    • pp.42-46
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    • 2017
  • The effects of the heat treatment temperature ($600^{\circ}C-1050^{\circ}C$) on the formation of $MgB_2$ and the superconducting properties have been examined. The self-synthesized $MgB_4$ and commercial Mg powders were used as raw materials for the formation of $MgB_2$. The superconducting critical temperatures ($T_cs$) of $MgB_2$ bulk superconductors prepared at $600^{\circ}C-850^{\circ}C$ were as high as 37-38 K regardless of the heat treatment temperature. However, because $MgB_4$ is more stable than $MgB_2$ at above $850^{\circ}C$, no superconducting signals were detected in the susceptibility-temperature curves of the samples prepared above $850^{\circ}C$. As for the critical current density ($J_c$), the sample heat-treated at a low temperature ($600^{\circ}C$) for a prolonged period (40 h) showed a Jc higher than those prepared at $650^{\circ}C-850^{\circ}C$ for a short period (1 h). The FWHM (full width at half maximum) result showed that the grain size of $MgB_2$ of the $600^{\circ}C$ sample was smaller than that of the other samples. The high $J_c$ of the $600^{\circ}C$sample is attributed to the presence of large numbers of grain boundaries, which can act as flux pinning centers of $MgB_2$.

Stress Spectrum Algorithm Development for Fatigue Crack Growth Analysis and Experiment for Aircraft Wing Structure (항공기 주익구조물의 피로균열 진전 해석 및 실험을 위한 응력 스펙트럼 알고리즘 개발)

  • Chun, Young Chal;Jang, Yun Jung;Chung, Tae Jin;Kang, Ki Weon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.12
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    • pp.1281-1286
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    • 2015
  • Fatigue cracks can be generated in aircraft as a result of the cumulative time spent during flight operations, which can extend for long periods of time and cover a variety of missions. If a crack occurs in an aircraft's main spar, it can generate many problems, including a lift time reduction. To solve this problem, it was necessary to perform an analysis of fatigue crack growth in the fatigue critical locations. Much time and expense is involved in generating the stress needed for a crack propagation analysis over a long period of time to obtain the amount of data required for an actual aircraft. In this paper, an algorithm is developed that can calculate the spectrum of stress over a long period of time for a mission by the Southwest Research Institute, which is based on the short-time load factor data produced using the peak-valley cycle counting method.

The Change of Characteristics in Clinical Decision Making in Novice Critical Care Nurses (중환자실 신규간호사의 임상의사결정 특성의 변화)

  • Kim, Dong-Oak;Kim, Mae-Ja
    • Journal of Korean Academy of Nursing Administration
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    • v.7 no.2
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    • pp.301-314
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    • 2001
  • The main purpose of this research is to describe comprehensively the processes of clinical decision making in novice critical care nurses through clinical experience. This research was an exploratory, longitudinal study using a fieldwork approach incorporating "think-aloud" method and in-depth interviews with the study participants. The study participants consisted of 5 novice nurses assigned to critical care units at a tertiary medical center located in Seoul, among a group of 27 novice nurses who started at the same period at this hospital. The data were collected from March 1999 to April 2000. The major findings of the study is that the novice nurses followed the analytic linear model of clinical decision making in the beginning, but were changed increasingly to follow the comprehensive, integrated model of clinical decision making. Through repeated experience that resulted in increasing repertoire of clinical schema and familiarity of task environments of clinical practice the novice nurses expanded their ability to arrive at comprehensive integration of information and to arrive at accurate and time-efficient decisions. Both the analytic, linear model mostly used at the beginning period and the comprehensive, integrated model that seems to be the mode significantly dependent upon experience seem to have strengths and weaknesses as decision making processes in clinical situations. Hence, it is imperative to develop an effective orientation and training program for novice nurses through the use of clinical preceptors. In addition, students should be exposed to the process of clinical decision making early in their nursing education through an appropriate clinical experiences and clinical assignments.

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The Correlation between the Moving Average of Precipitation and Groundwater Level in Southern Regions of Korea (한국 남부지방의 강수량 이동평균과 지하수위의 상관관계)

  • Yang, Jeong-Seok;Ahn, Tae-Yeon
    • The Journal of Engineering Geology
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    • v.18 no.4
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    • pp.393-403
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    • 2008
  • The relationship between precipitation and groundwater level and the correlation between the moving average of precipitation and goundwater level were analyzed for the southern area of Korean peninsular. There were somewhat different patterns of seasonal fluctuation of groundwater level data. The groundwater level data tends to decrease in dry spell and increase in wet spell however the range between maximum and minimum values is quite different for each gauging point. The maximum correlation coefficient for each gauging station is obtained in a range of 20- to 130-day moving average period of precipitation. The critical infiltration, which is the maximum daily infiltration averaged throughout watershed, value is turned out to have the range of 10 to 90 mm and the moving average period is 10 to 150 days. We could have stronger correlation when we consider critical infiltration and modify the original precipitation data than we use original precipitation data.

A Pilot Study on Effects of Critical Pathway Application for Hwa-Byung (화병 표준진료지침 적용효과에 대한 Pilot 분석)

  • Eom, Yoon-Ji;Kwon, Do-Hyung;Kim, Yun-Na;Lee, Hyun-Woo;Chung, Sun-Yong;Cho, Seung-Hun
    • Journal of Oriental Neuropsychiatry
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    • v.32 no.4
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    • pp.337-343
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    • 2021
  • Objectives: To investigate effectiveness and satisfaction of applying critical pathway (CP) to Hwa-byung outpatients. Methods: Subjects were 32 outpatients who were diagnosed with Hwa-byung between January 1 and 2021 to October 31, 2021. Among these patients, 18 patients were applied with CP and 14 patients received treatment without applying CP. Their medical records and administration records were retrospectively analyzed. Data were analyzed by mean, standard deviation, and t-test using SPSS 26.0 program. Results: Mean total treatment period significantly decreased in the CP group compared with the non-CP group. Medical expenses were classified by treatment period, per visit, and patient charges per type of visit. When analyzed specifically by detailed items, there was a decreasing tendency in total medical expenses, uncovered medical expenses, and patient charges but an increasing tendency in covered medical expenses, although some of these changes were not statistically significant. Satisfaction score increased in the CP group compared with the non-CP group in general, although not all increases were statistically significant. Conclusions: Applying CP may contribute to the reduction of medical expenses and improvement of medical service quality. Further research on the development of CP for various diseases and the application of CP under various circumstances is needed.