• 대한수학교육학회지:수학교육학연구
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• 제20권2호
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• pp.185-202
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• 2010

본 연구는 중등수학교육에서 도구화된 CAS에 기반한 최적화 문제해결 활동을 통해 CAS가 교육과정 내용제시 순서에 영향을 줄 수 있는지를 분석하기 위해 설계되었다. 이를 위하여 본 연구자는 CAS를 활용한 최적화 문제해결 활동을 구안하였으며 3개월간의 CAS 활용 수업 경험이 있으나 아직 미적분학을 접해 본 적이 없는 고등학교 2학년 7명을 선정하여 총 9차시의 수업을 실시하고, 수업녹화자료와 면담을 통해 학생들의 활동을 분석하였다. 분석 결과, 학생들은 CAS를 이용하여 미 학습된 교육내용인 미분과 삼차방정식, 무리방정식의 해구하기와 그래프 분석이 포함된 최적화 문제해결활동을 수준 높게 다룰 수 있는 것으로 나타나 CAS가 교육과정 내용제시 순서에 영향을 줄 수 있음을 확인할 수 있었다.

• 성인간호학회지
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• 제27권4호
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• pp.472-479
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• 2015

Few instruments are available to measure nurses' perceptions of cultural competence in South Korea. Furthermore, the equivalence of factors between original and translated instruments has not been evaluated. The specific aims of this study were to identify the validity and reliability of a Korean version of the Cultural Awareness Scale (K-CAS) and to evaluate the equivalence of factors between the original CAS and the K-CAS. A total of 515 nursing students completed the 26-item K-CAS, 28-item Caffrey Cultural Competence in Healthcare Scale (CCCHS), and eight-item Openness to Diversity and Challenge Scale (ODCS). The K-CAS exhibited good reliability (${\alpha}=.83$) and construct validity by correlating with the CCCHS (r=.344, p<.001) and ODCS (r=.394, p<.001). Confirmatory factor analysis results of the K-CAS confirmed the same factor structure as the original CAS. The K-CAS could be a useful tool to assess the concept of cultural competence among nursing students and nurses.

• 천문학회지
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• 제48권4호
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• pp.207-212
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• 2015

We introduce the Lee Sang Gak Telescope (LSGT), a remotely operated, robotic 0.43-meter telescope. The telescope was installed at the Siding Spring Observatory, Australia, in 2014 October, to secure regular and exclusive access to the dark sky and excellent atmospheric conditions in the southern hemisphere from the Seoul National University (SNU) campus. Here, we describe the LSGT system and its performance, present example images from early observations, and discuss a future plan to upgrade the system. The use of the telescope includes (i) long-term monitoring observations of nearby galaxies, active galactic nuclei, and supernovae; (ii) rapid follow-up observations of transients such as gamma-ray bursts and gravitational wave sources; and (iii) observations for educational activities at SNU. Based on observations performed so far, we find that the telescope is capable of providing images to a depth of R = 21:5 mag (point source detection) at 5-σ with 15 min total integration time under good observing conditions.

• 대한간호학회지
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• 제51권3호
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• pp.305-319
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• 2021

Purpose: The purpose of this study was to develop a measurement tool for a positive nursing organizational culture and to verify its reliability and validity. Methods: A conceptual framework and construct factors were extracted through an extensive literature review and in-depth interviews with nurses. The final version of the preliminary tool for the main survey was confirmed by experts through a content validity test and a preliminary survey of 40 nurses. Subsequently, the final tool was developed using a validity and reliability test containing 43 preliminary items. The final version of the tool was used with 327 hospital nurses in the testing phase for the main survey to assess validity and reliability. Results: From the factor analysis, 4 factors and 26 items were selected. The factors were positive leadership of the nursing unit manager, pursuit of common values, formation of organizational relationships based on trust, and a fair management system. The entire determination coefficient was 67.7%. These factors were verified through convergent, discriminant, and concurrent validity testing. The internal consistency reliability was acceptable (Cronbach's α = .95). Conclusion: Both the validity and reliability of the scale were confirmed demonstrating its utility for measuring positive nursing organizational culture. It is expected to be used for education, research, and practical performance policies regarding the nursing organizational culture.

• 한국기계가공학회지
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• 제21권3호
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• pp.49-55
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• 2022

The design of a battery package and a BMS module for applications using seawater rechargeable batteries, which are known as next-generation energy storage devices, is proposed herein. Seawater rechargeable batteries, which are currently in the initial stage of research, comprise primarily components such as anode and cathode materials. Their application is challenging owing to their low charge capacity and limited charge/discharge voltage and current. Therefore, we design a method for packaging multiple cells and a BMS module for the safe charging and discharging of seawater rechargeable batteries. In addition, a prototype seawater rechargeable battery package and BMS module are manufactured, and their performances are verified by evaluating the prevention of overcharge, overdischarge, overcurrent, and short circuit during charging and discharging.

• 천문학회지
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• 제54권3호
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• pp.89-102
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• 2021

Even in an era where 8-meter class telescopes are common, small telescopes are considered very valuable research facilities since they are available for rapid follow-up or long term monitoring observations. To maximize the usefulness of small telescopes in Korea, we established the SomangNet, a network of 0.4-1.0 m class optical telescopes operated by Korean institutions, in 2020. Here, we give an overview of the project, describing the current participating telescopes, its scientific scope and operation mode, and the prospects for future activities. SomangNet currently includes 10 telescopes that are located in Australia, USA, and Chile as well as in Korea. The operation of many of these telescopes currently relies on operators, and we plan to upgrade them for remote or robotic operation. The latest SomangNet science projects include monitoring and follow-up observational studies of galaxies, supernovae, active galactic nuclei, symbiotic stars, solar system objects, neutrino/gravitational-wave sources, and exoplanets.

• Journal of Korean Neurosurgical Society
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• 제61권5호
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• pp.568-573
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• 2018

Objective : Thoracic pedicles have special and specific properties. In particular, upper thoracic pedicles are positioned in craniocaudal plane. Therefore, manipulation of thoracic pedicle screws on the left side is difficult for right-handed surgeons. We recommend a new position to insert thoracic pedicle screw that will be much comfortable for spine surgeons. Methods : We retrospectively reviewed 33 patients who underwent upper thoracic pedicle screw instrumentation. In 15 patients, a total of 110 thoracic pedicle screws were inserted to the upper thoracic spine (T1-6) with classical position (anesthesiologist and monitor were placed near to patient's head. Surgeons were standing classically near to patient's body while patients were lying in prone position). In 18 patients, a total of 88 thoracic pedicle screws were inserted to the upper thoracic spine with the new standing position-surgeons stand by the head of the patient and the anesthesia monitor laterally and under patient's belt level. All the operations performed by the same senior spine surgeons with the help of C-arm. Postoperative computed tomography scans were obtained to assess the screw placement. The screw malposition and pedicle wall violations were divided and evaluated separately. Cortical penetration were measured and graded at either : 1-2 mm penetration, 2-4 mm penetration and >4 mm penetration. Results : Total 198 screws were inserted with two different standing positions. Of 198 screws 110 were in the classical positioning group and 88 were in the new positioning group. Incorrect screw placement was found in 33 screws (16.6%). The difference between total screw malposition by both standing positions were found to be statistically significant (p=0.011). The difference between total pedicle wall violations by both standing positions were found to be statistically significant (p=0.003). Conclusion : Right-handedness is a problem during the upper thoracic pedicle screw placement on the left side. Changing the surgeon's position standing near to patient's head could provide a much comfortable position to orient the craniocaudal plane of the thoracic pedicles.

• 천문학회지
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• 제51권6호
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• pp.207-214
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• 2018

A coelostat is often used for solar observations, because it corrects the image rotation automatically by guiding sunlight into a fixed telescope with two plane mirrors. For the purposes of education and spectroscopic observation, the solar group at Seoul National University (SNU) plans to develop the SNU coelostat (SNUC) and install it in the SNU Astronomical Observatory (SAO). Requirements of the SNUC are < 1" positioning accuracy with 30 cm beam size on the entrance pupil in the compact dome. To allow for installation in the small dome, we design a compact slope type coelostat with a 45 cm primary plane mirror and a 39 cm secondary plane mirror. The motion of the SNUC is minimized by fixing the position of the slope frame. Numerical simulations of the available observational time of the designed coelostat shows that the sun can be observed ay all times from June to early August and at least three hours in other months. Since the high accuracy driving motors installed in the SNUC can be affected by external environment factors such as humidity and temperature variations, we design a prototype to test the significance of these effects. The prototype consists of a 20 cm primary plane mirror, a 1 m slope rail, a direct drive motor, a ballscrew, a linear motion guide, an AC servo motor, a reduction gear and a linear encoder. We plan to control and test the accuracy of the prototype with varying atmospheric conditions in early 2019. After testing the prototype, the SNUC will be manufactured and installed in SAO by 2020.

• The Plant Pathology Journal
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• 제16권3호
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• pp.130-136
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• 2000

Differences in physiological and biochemical responses between sensitive and tolerant rice cultivars to ozone were investigated to develop reliable indications of early ozone damage. Three Korean local rice cultivars -sen-sitive cultivar Dongjin (DJ), moderately tolerant cultivar Hwayeong (HY) and tolerant cultivar Ilmee (IM) were exposed to ozone at the concentrations of 100 nl $\textrm{l}^{-1}$ or 200 nl $\textrm{l}^{-1}$ , 8 h per day for 10 days in a controlled-environment fumigation chamber. The rice cultivars seemed to be endurable to ozone stress at the concentration of 100 nl $\textrm{l}^{-1}$ which is frequently monitored during the growing season in summer. However, severe damage was induced and differential sensitivity was clearly noted among the rice cultivars at the higher ozone concentration. Activation of the glutathion (GR) -ascorbate peroxidase (APX) cycle was likely to be responsible for protection of rice plants against ozone exposure, relating difference in sensitivity of rice cultivars to ozone. Photosynthetic activity appeared to be one of sensitive responses, for which chlorophyll fluorescence and leaf greenness can together provide a very reliable index, a degree of photosynthetic damages by ozone. Formation of malondialdehyde (MDA) was also considered as an indication that can differentiate cultivars sensitivity to ozone. However, the changes in polyamines and total phenolics were not consistent with exposed ozone concentrations and/or ozone sensitivity of the cultivars. The behavior of polyamines and phenolics in the damaged plants at high ozone levels could be interpreted as an indication of ozone injury rather than activation of additional protection mechanisms scavenging active oxygen species formed by ozone. Several responses triggered by ozone could explain the differential sensitivity of the rice cultivars and be used as reliable indications of relative ozone damage to rice plant.

• 한국항행학회논문지
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• 제17권4호
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• pp.442-448
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• 2013

제어계측 시스템과 정보시스템은 서로 차이가 있으며 두 시스템의 보안설계가 다르다. 이러한 문제점을 해결하기 위해 제어계측 시스템의 보안통제를 설계하기 위해서는 보안통제가이드를 기본으로 한 정책 설정 및 모델링 작업의 필요성이 대두되고 있다. 본 논문에서는 제어계측시스템 환경에서 사이버 보안 통제를 지원하기 위하여 보안규제 가이드를 기반으로 역할, 보안 통제 별 및 문서간의 관계스키마를 설계하였고, 설계된 스키마는 보안규제가이드를 준수하기 위한 사이버 보안 통제 구축 지원 시스템의 계획, 설계, 구현을 지원 하는 데이터베이스와 내용으로 활용이 가능하다. 이후 제안된 스키마를 활용하여 시스템 프로세스를 설계하고 제어계측 시스템에 최적화된 보안통제지원 시스템을 개발한다.