• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.455-458
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• 2006

관성항법장치는 관성항법장치를 구성하는 관성센서인 가속도계 및 자이로의 오차요소에 의해 수평축 항법오차는 슐러주기를 가지고 서서히 증가하는 반면에 수직축 오차는 기하급수적으로 증가하는 특성을 가지고 있다. 그러므로 관성항법장치를 장시간 운용하는 경우에는 비관성 보조센서를 이용하여 관성항법장치의 수직축 항법오차에 대한 보정을 반드시 수행하여야 한다. 관성항법장치의 수직축 항법오차를 보정하기 위한 비관성 보조센서의 일종인 기압고도계는 계측된 대기압과 모델링 된 대기압을 비교하여 항체의 고도를 측정하는 방법을 이용하기 때문에 항체의 자세변화 등에 매우 민감하고 대기압 측정오차에 의해 매우 큰 진폭의 잡음 및 바이어스가 존재한다. 본 논문에서는 시뮬레이션 및 시험을 통하여 기압 고도계의 잡음 및 바이어스 오차 성분에 의한 baro-inertial 고도루프의 성능분석 결과를 제시하고 기압고도계 잡음에 둔감한 INS/기압고도계 칼만필터의 설계 결과를 제시한다.

• Journal of Elementary Mathematics Education in Korea
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• v.15 no.3
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• pp.509-531
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• 2011

This study is to determine if teaching of measuring the area of plane figures in elementary school is successful. While they teach to measure the area of figures in elementary school, students don't measure the segment of the figure directly until now. The figures are presented with auxiliary line and numerical information. When students measure the area of such figure, they do only substitute the number and calculate it. This study found that such teaching is not successful and propose the new teaching method of measuring the plane figures.

• The Mathematical Education
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• v.51 no.4
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• pp.471-484
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• 2012

It is not easy to find the auxiliary line to solve the problem in connection with the circle, where it is the problem finding the central angle or angle at the circumference in a circle. The purpose of the study is to give an aid for this difficulties. The angle at the circumference is closely related to the arc. And so we looked into the problem in connection with the angle at the circumference in point of view of the arc. We have got the following the results. It is not necessary to draw the auxiliary line when solving the problem in connection with the angle at the circumference in point of view of the arc. And we can find the reason to draw the specific auxiliary in point of view of the arc. We hope that the results of research are given aids to a lot of students.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.04a
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• pp.729-731
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• 2014

플래시 메모리에서 B-tree 데이터를 저장하고 관리[4, 5]할 때 빈번한 수정과 구조변동으로 인해 발생하는 블록에 대한 쓰기와 지우기 연산의 비용으로 인해 플래시 메모리의 사용 수명을 단축시키는 문제를 해결하기 위해 현재 많이 쓰이고 있는 로그 저장방식을 검토하고 이를 효율적으로 B-tree에 저장하고 관리하도록 동적 블록 그룹핑과 순환 순서 기반의 저장 알고리즘으로 제안 된 GRR (Ground Round Robin) 기법을 보조 로그 블록을 할당하여 머지횟수를 줄일 수 있는 알고리즘을 제안한다.

• Journal of Space Technology and Applications
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• v.3 no.1
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• pp.44-57
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• 2023

In order for a latecomer in deep-space exploration such as Korea to quickly keep pace with advanced deep-space exploration countries in the mutually-beneficial space exploration market, it is essential to derive a deep-space probe reference model that can reduce development period and cost. In this paper, concept and configuration for the deep-space probe reference model consisting of basic, lightweight, and expansion types are newly presented, which are based on commonly required designs for various deep-space probes. The proposed configuration adopts modular design so that the expandability and design/implementation efficiency are improved. In addition, the electrical system design pursuing lightweight and expandability is also described, which is applicable to the proposed three-types of deep-space probe reference model.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.8
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• pp.86-92
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• 2009

In order to minimize ac mutual coupling, the auxiliary electrode are located at a right angle in measuring ground impedance. In case that the measurement space is limited, the alternative method is employed. At that time, it is necessary to investigate the measurement errors due to ac mutual coupling and earth mutual resistance in measuring the ground impedances. 'This paper presents the measurement accuracy according to the location of the current and potential auxiliary electrodes in measuring ground impedance of vertically or horizontally buried ground electrode. The measurement errors due to ac mutual coupling were evaluated Consequently, the effect of ac mutual coupling on the measurement accuracy for horizontally buried ground electrode is greater than that for vertically buried ground electrode. Measurement errors due to ac mutual coupling is the largest when the current and potential auxiliary electrodes are located in parallel. The 61.8[%] rule is inappropriate in measuring ground measurement. Theoretically, in case that the angle between the current and potential auxiliary electrodes is 90$[^{\circ}]$, there is no ac mutual coupling. If it is not possible to route the current and potential auxiliary electrodes at a right angle with limitation of measurement space, the location of these electrodes with an obtuse angle is preferred to that with an acute angle in reducing the measurement errors due to ac mutual coupling.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.389-394
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• 2015

There is a progressive development in the medical imaging technology, especially of descriptive capability for anatomical structure of human body thanks to advancement of information technology and medical devices. But however maintenance of correct posture is essential for the medical imaging checkup on the shoulder joint requiring rotation of the upper limb due to the complexity of human body. In the cases of MRI examination, long duration and fixed posture are critical, as failure to comply with them leads to minimal possibility of reproducibility only with the efforts of the examiner and will of the patient. Thus, this study aimed to develop an auxiliary device that enables rotation of the upper limb as well as fixing it at quantitative angles for medical imaging examination capable of providing diagnostic values. An auxiliary device has been developed based on the results of precedent studies, by designing a 3D model with the CATIA software, an engineering application, and producing it with the 3D printer. The printer is Objet350 Connex from Stratasys, and acrylonitrile- butadiene-styrene(ABS) is used as the material of the device. Dimensions are $120{\times}150{\times}190mm$, with the inner diameter of the handle being 125.9 mm. The auxiliary device has 4 components including the body (outside), handle (inside), fixture terminal and the connection part. The body and handle have the gap of 2.1 mm for smooth rotation, while the 360 degree of scales have been etched on the handle so that the angle required for observation may be recorded per patient for traceability and dual examination.

• Journal of the Korean Society of Radiology
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• v.13 no.4
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• pp.605-611
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• 2019

The purpose of this study is to manufacture a multi-function device (MFD) which can be applied to various types of weight-bearing view of the lower leg, and to compare the results with the images from the existing weight-bearing platforms (WBPs), thereby suggesting a clinical utilization. The MFD was manufactured, by considering the minimum adjustable heights of the platform for weight-bearing foot/ankle, platform for hindfoot alignment view, and X-ray tube of the X-ray device. A foot/ankle phantom was used to take the images of weight-bearing lateral foot in MFD and WBPs to compare the resolutions of the X-ray images using a quick modulation transfer function (MTF) program. Between both the images taken from the MFD and WBPs, there was no statistically significant difference found in the mean cycles per pixel (C/P) and the lines per image height (LPH) of the 50%-Contrast Spatial Frequency (MTF50), and 10-90% of Maximum Energy Rise Distance (10-90%), where p>0.05. The MFD is suggested for its clinical trial as a useful positioning device that can secure the patient's safety and manifoldly perform various inspections. Also, the recommendation of the positioning device as a policy can activate dedicated manufacturers, while also improving the quality of medical services.

• Journal of Chest Surgery
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• v.34 no.2
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• pp.162-166
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• 2001

배경: 흉선암은 드문 질환으로 치료경과 및 예후가 침윤성 흉선종에 비해 나쁜 것으로 알려져 있으며 병기의 분류나 병기에 따른 치료방법이 아직 표준화 되어있지 않아 치료에 어려운 점이 있다. 이에 본교실에서 흉선암으로 진단되었던 환자들의 피료방법 및 성적을 분석하여 그 결과를 보고하고자 한다. 대상 및 방법: 계명대학교 동산의료원 흉부외과학교실에서는 1984년 8월에서 흉선암으로 진단되었던 8례의 환자를 대상으로 의무기록을 참고하여 병기에 따른 치방법료 및 예후 등을 후향적으로 분석하였다. 결과: 연령은 23세에서 67세까지로 평균 46세였으며 전흉부통증이 주증상이었다. 조직학적으로는 임파상피양암(lymphoepithelioma-like carcinoma)이 2례, 편평상피암(squamous cell carcinoma)이 2례, 기저세포암(basaloid carcinoma)이 1례, 혼합형(mixed type)이 3례 있었다. 임상적 병기분류는 Masoka의 분류법을 사용하였으며 제I기 2례, 제II기 4례, 제III기 1례, 제IVAr기가 1례 있었다. 4례의 환자에서는 종양의 완전적출이 가능했으며 3례에서는 고식적 수술을 시행하였다. 1례의 환자는 주위조직으로의 침윤과 심낭에 퍼져있어 조직생검만을 시행하였다. 전례에서 보조적 항암치료를 받았고 술후 병기가 제III기 이상이거나 종양의 절제가 불완전했던 5례의 환자에서는 보조적 방사선치료를 병행하였다. 이들 중 5례에서 술후 보조적 항암치료 및 방사선치료를 받고 현재까지 생존해있다. 평균추적기간은 55.3$\pm$64.6 개원이었고, 3례의 환자는 사망하였으며 4례의 환자는 종양의 재발증거 없이 생존해있다. 결론: 종양의 조기진단과 완전종양적출후 적극적인 보조적 항암치료 및 방사선치료가 흉선암을 치료하는데 도움이 될 것으로 사료된다.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.49-57
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• 2011

This study deals with the traffic accident of arterial link sections in the case of Cheongju. The purpose of the study is to develop the traffic accident model by the function of arterial links. In pursuing the above, this study gives particular attentions to developing the appropriate models using the accident data of main and minor arterial roads divided by 472 small link sections. The main results analyzed are as follows. First, as the t test on the accident characteristics of main and minor arterial roads shows that there are differences in the number of accident and EPDO(equivalent property damage only) between two roads, the development of models by function is analyzed to be appropriate. Second, it is analyzed that ZINB models are all statistically suitable to the number of accident and EPDO of main arterial roads. Third, the analysis shows that EPDOs of minor arterial roads fit to ZINB, and the number of the accident fit to ZIP model. Finally, the common variables of main arterial roads are evaluated to be the traffic volume and the number of inflection point, and those of minor be the average grade.