• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.81-82
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• 2018

선박안전법에 따라 대다수의 관공선 주기관은 8년마다 정기 개방검사를 해야 한다. 주기관 특성상 개방검사는 많은 예산 소요 및 엔진 효율성의 저하가 우려되어 이를 해결하고자 관련법에 따라 8년간 개방검사 면제 사전 준비로 예산을 절감하고 기관의 성능을 최적화 시켰다.

• Journal of Korea Ship Safrty Technology Authority
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• v.14
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• pp.85-86
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• 2004

고속기관과 같은 특수구조의 기관에 대하여 제작기술과 내구성 등이 과거에 비해 향상된 점을 고려하고 잦은 개방검사에 따른 성능저하를 방지하기 위해 현행의 획일적으로 정해진 기관개방검사주기를 제조자의 개방권고 시간과 정비상태 및 선박의 특성에 따라 개방검사주기를 달리 적용함으로써 고속기관의 성능보호와 민원의 편의를 도모하며, 현행제도상의 일부 미비점을 개선, 보완하려는 것임.<중략>

• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.887-900
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• 2011

Teachers use explanations to communicate important scientific ideas to students. Consequently, all biology teachers should be evaluated to determine how effective they are at constructing and communicating biological explanations. Open response questions are required to detect pre-service biology teachers' abilities to communicate robust and accurate scientific explanations. Nevertheless, multiple-choice questions are typically preferred by educators because of the common drawbacks of using open-response instruments, such as scoring time, inter-rater scoring disagreements, and delayed feedback to test takers. This study aims to measure pre-service biology teachers' competence in building scientific explanations and to investigate how accurately multiple-choice questions predict the results of open-response questions. One hundred twenty four pre-service biology teachers participated in the study and were administered 20 multiple-choice items and three open-response items designed to measure the accuracy and quality of their explanations of evolutionary change. The results demonstrated that pre-service teachers displayed higher competence when tested with multiple choice items than when tested with open response items. Moreover, scores derived from multiple-choice items poorly predicted the scores derived from open-response items. Multiple-choice items were also found to be poor measures of the consistency, purity and abundance of conceptual elements in teachers' evolutionary explanations. Additionally, many teachers held mixed-models composed of both scientific and naive ideas, which were difficult to detect using multiple-choice formats. Overall, the study indicates that multiple-choice formats are poorly suited to measuring several aspects of biology teachers' knowledge of evolution, including their ability to generate scientific explanations. This study suggests that open-response items should be used in teacher education programs to assess pre-service teachers' explanatory competency prior to being permitted to teach science to children.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.433-438
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• 2011

Purpose: To investigate the proper distance from patient to target when measuring refractive error using open view target type auto-refractor(OVTAR), it was compared refractive errors between by OVTAR using N-vision-K5001 auto-refractor and internal fixation target type auto-refractor(IFTAR) using Canon auto-refractor. Methods: 21 subjects(42 eyes) aged 22.2(${\pm}$3.4) years old who had over 1.0 of corrected visual acuity and no ocular disease were participated for this study. Noncycloplegic measurements of refractive error were performed using a IFTAR(RK-F1, Canon, Japan) and an OVTAR(N-vision-K5001, Shin-nippon, Japan). The distances from subjects to targets in using the open the view target type auto-refractor were 1 m, 3 m, 4 m and 6 m. The refractive errors were compared between by IFTAR and by 1 m, 3 m, 4 m and 6 m target distances respectively using OVTAR. Results: At 1 m fixation distance the mean of refractive errors for total subjects was not significantly different between by OVTAR(-2.75${\pm}$1.84 D) and by IFTAR(-2.95${\pm}$2.04 D)(p=0.06). However at 3, 4 and 6 m fixation distance refractive errors by OVTAR were significantly lower myopic refractive errors than by IFTAR(p<0.05). Conclusions: The distance from subject to fixation target is needed over 3 m for the measurement of refractive error using OVTAR even not to 5~6 m distance.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.9
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• pp.26-34
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• 1998

This paper presents a characterization method for faults of circuit patterns on MCM(Multichip Module) or PCB(Printed Circuit Board) substrates with electron beams of a SEM(Scanning Electron Microscope) by inducing voltage contrast on the signal line. The experimentation employes dual potential electron beams for the fault characterization of circuit patterns with a commercial SEM without modifying its structure. The testing procedure utilizes only one electron gun for the generation of dual potential electron beams by two different accelerating voltages, one for charging electron beam which introduces the yield of secondary electron $\delta$ < 1 and the other for reading beam which introduces $\delta$ > 1. Reading beam can read open's/short's of a specific net among many test nets, simultaneously discharging during the reading process for the next step, by removing its voltage contrast. The experimental results of testing the copper signal lines on glass-epoxy substrates showed that the state of open's/short's had generated the brightness contrast due to the voltage contrast on the surface of copper conductor line, when the net had charged with charging electron beams of 7KV accelerating voltages and then read with scanning reading electron beams of 2KV accelerating voltages in 10 seconds. The experimental results with Au pads of a IC die and Au plated Cu pads of BGA substrates provided the simple test method of circuit lines with 7KV charging electron beam and 2KV reading beam. Thus the characterization method showed that we can test open and short circuits of the net nondestructively by using dual potential electron beams with one SEM gun.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.1
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• pp.55-62
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• 2006

Clinical evaluation of the Closed-view autorefractor and Open-view autorefractor was performed to examine validity and repeatability compared with subjective refraction. Measurements of refractive error were performed on 126 eyes of 65 subjects (aged $26{\pm}7.5$ years) subjectively noncycloplegic. Intersession repeatability of the Closed-view and Open-view were also assessed on all 65 subjects together with Intersession repeatability on 7 to 14 days intervals. Spherical powers and spherical equivalent values of subjective refraction and autorefractions by Closed-view and Open-view were analyzed by paired T-test. The mean spherical powers of subjective refraction, Closed-view and Open-view were determined to be $-2.125{\pm}2.155D$, $-2.146{\pm}1.907D$, $-2.117{\pm}2.121D$, respectively. The mean spherical equivalent values of subjective refraction, Closed-view and Open-view were determined to be $-2.362{\pm}2.204D$, $-2.391{\pm}1.967D$, $-2.366{\pm}2.162D$, respectively. The results showed that the refractive errors as measured by the Closed-view and Open-view were found to be similar to the subjective refraction in all components.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.3
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• pp.907-935
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• 2010

The purpose of this study was to investigate the effects of using open-ended problems in ability-level activities in mathematics instruction and to draw some informative conclusions in order to improve the practice of teaching and learning mathematics in the elementary school. To fulfill the purpose, the research questions were established as follows: 1. Is there any difference between the academic achievements of the experimental group(doing ability-level activities using open-ended problems) and the control group(doing general ability-level activities)? 2. Which sub-group(grouped by achievement score in pretest) get affected most by ability-level activities using open-ended problem in the experimental group? 3. What kinds of responses do students show in their ability-level activities using open-ended problems? By applying t-test and analysing the response, the conclusions were drawn as follows: First, using open-ended problems in ability-level activities has positive effects on the academic achievement of the experiment group. The mean of posttest scores of the experiment group was statistically meaningfully higher(p<.05). Second, using open-ended problems in ability-level activities affect most to the achievement of lower sub-group in the experiment group. The mean of posttest scores of lower sub-group in the experiment group was statistically meaningfully higher than that of control group(p<.05). Third, students showed various and creative response in their ability-level activities using open-ended problems.

• Communications of Mathematical Education
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• v.11
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• pp.259-277
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• 2001

본 연구는 개방형 문제를 활용한 평가가 수학적 창의력에 미치는 효과를 분석함으로써 수학적 창의력을 신장시킬 수 있는 평가 방법을 찾는데 그 목적이 있다. 이를 위해 대구광역시 소재의 C중학교 2학년 1개반과 S중학교 2학년 1개반을 임의로 선정하여 한 반은 개방형 문제를 활용한 평가 집단으로 하고 다른 한 반은 전통적 평가 집단으로 무선 할당하여 실험연구를 실시하였다. 실험처치는 두 집단에게 서로 다른 유형의 평가를 실시하는 것으로, 실험집단은 개방형 문제를 평가과제로 하여 실험집단 담임 교사가 평가를 실시하였으며, 비교집단은 객관식 및 주관식 단답형 문제를 평가과제로 하여 비교집단 담임교사가 전통적인 평가를 실시하였다. 본 연구에서 사용한 검사도구는 수학적 창의력 검사로 사전 사후검사 모두 같은 검사지를 사용하였다. 사후 수학적 창의력 검사의 평균의 차를 t-검정한 결과 유의도p=.025(p < .05)로 실험집단과 비교집단 사이에는 통계적으로 유의미한 차가 있는 것으로 나타났다. 수학적 창의력의 각 요소별로 차이가 있는지 알아보기 위해 사후 창의력 검사의 각 요소별로 평균의 차를 t-검정한 결과, 유창성과 융통성은 각각 유의도 p=.030, p=.040으로 p < .05 수준에서 통계적으로 유의미한 차이가 있었으며, 독창성은 유의도 p=.052로 p < .1 수준에서 통계적으로 유의미한 차이를 보였다. 연구결과 개방형 문제를 활용한 평가가 전통적 평가보다 수학적 창의력 향상에 더 효과적이며, 수학적 창의력의 세 가지 요소(유창성, 융통성, 독창성)의 향상에도 효과적인 것으로 나타났다. 결론적으로 개방형 문제를 활용한 평가가 수학적 창의력 신장에 효과적인 방법임을 시사한다.질공학적 특성의 위도별, 깊이별 변화는 탄산질 퇴적물과 규질 퇴적물의 분포, 수층의 생산성 및 수심변화에 따른 용해도와 퇴적을 차이 그리고 침식 및 재퇴적작용 등 퇴적 과정이 위도별로 달랐기 때문으로 판단된다.haetoceros resting spores/Chaetoceroe vegetative cells도 80 cm 보다 상층에서는 높게 나타나 규조온도지수 분포와도 일치하는 경향을 보인다. 이상의 규조군집 분석 결과에 의하면, 홀로세의 후빙기동안 본 연구 지역인 동해 북동부에는 대마 난류의 유입이후 현재와 유사한 환경이 우세하게 발달했으나, 난류종 P. doliolus의 변화는 동해내에서 대마난류의 세기가 반복되었음을 지시하고 있다./3 수준으로 높다. 결론적으로 풍부한 화학물질들을 함유한 제주해류는 남해 및 동해의 생지화학적 과정들에 있어 상당히 중요함을 시사한다.다. 수조 상층수 중 Cu, Cd, As 농도는 모든 FW, SW수조에서 시간이 지남에 따라 일관성 있게 감소하였고, 제거속도는 Cu가 다른 원소에 비해 빨랐다. 제거속도는 FW 3개 수조 중 FW5&6에서 세 원소 모두 가장 느렸고, SW 3개 수조 중에서는 SW1&2에서 가장 빨랐다. SW와 FW간 제거속도 차이는 세 원소 모두 명확치 않았다 Cr은 FW에서 전반적으로 감소하는 경향을 보였지만 SW에서는 실험 초기에 감소하다 24시간 이후에는 증가 후 일정한 양상을 보였다. Pb은 FW에서 전반적으로 감소했지만 SW에서는 초기에 급격히 증가 후 다시 급격히 감소하는 양상을 보였다 Pb 또한 Cu, Cd, As와 마찬가지로 SW1&2에서 제거속도가 가장 빠르게 나타났다. FW 상층수 중 Hg는 시간에 따라 급격히 감소했고,

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.359-362
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• 2015

A Korean water deer was rescued after being hit by a motor vehicle. Clinical and radiographic examination revealed a grade III open fracture of the right metacarpus with severe soft tissue injury. The water deer underwent closed reduction of the fracture, which was stabilized by the application of the Ilizarov method of 4-ring circular external skeletal fixation (CESF) as a minimally invasive technique. The water deer was successfully released into the wild. CESF was advantageous for the stabilization of open comminuted fracture and the management of a severely contaminated wound in a Korean water deer. CESF can be used successfully in wild deer with good tolerance and minimal complications.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.1
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• pp.63-69
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• 2006

Clinical evaluation by Astigmatic Components of autorefractors was performed to examine validity and accuracy compared with subjective refraction. The mean cylindrical powers of Astigmatic Components of Subjective Refraction, Closed-view and Open-view were found to be $-0.689{\pm}0.516D$, $-0.691{\pm}0.530D$, $-0.470{\pm}0.507D$, respectively. The Difference of cylindrical Components between Subjective Refraction and Closed, Open-view were found to be $0.002{\pm}0.191D$, $0.015{\pm}0.137D$, respectively. Approximately 85% of Closed-view and Open-view autorefractor measurements were within ${\pm}20^{\circ}$ range of the difference of cylindrical axis with subjective refraction. The mean $J_0$ Components of Astigmatic Components of subjective refraction, Closed-view and Open-view were found to be $-0.155{\pm}0.332D$, $-0.004{\pm}0.178D$, $-0.001{\pm}0.156D$, respectively. The mean $J_{45}$ Components of Astigmatic Components, Closed-view and Open-view were found to be $-0.023{\pm}0.227D$, $-0.026{\pm}0.172D$, $-0.014{\pm}0.182D$, respectively. Both of the Closed-view and Open-view refractor showed available accuracy in measuring astigmatic components.