• Journal of Korean Neurosurgical Society
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• 제56권5호
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• pp.400-404
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• 2014

Objective : Clip artifacts limit the visualization of intracranial structures in CT scans from patients after aneurysmal clipping with cobalt alloy clips. This study is to analyze the parameters influencing the degree of clip artifacts. Methods : Postoperative CT scans of 60 patients with straight cobalt alloy-clipped aneurysms were analyzed for the maximal diameter of white artifacts and the angle and number of streak artifacts in axial images, and the maximal diameter of artifacts in three-dimensional (3-D) volume-rendered images. The correlation coefficient (CC) was determined between each clip artifact type and the clip blade length and clip orientation to the CT scan (angle a, lateral clip inclination in axial images; angle b, clip gradient to scan plane in lateral scout images). Results : Angle b correlated negatively with white artifacts (r=-0.589, p<0.001) and positively with the angle (r=0.636, p<0.001) and number (r=0.505, p<0.001) of streak artifacts. Artifacts in 3-D images correlated with clip blade length (r=0.454, p=0.004). Multiple linear regression analysis revealed that angle b was the major parameter influencing white artifacts and the angle and number of streak artifacts in axial images (p<0.001), whereas clip blade length was a major factor in 3-D images (p=0.034). Conclusion : Use of a clip orientation perpendicular to the scan gantry angle decreased the amount of white artifacts and allowed better visualization of the clip site.

• 인터넷정보학회논문지
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• 제17권2호
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• pp.39-47
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• 2016

일반적으로 소프트웨어 R&D 프로젝트에서는 프로그램 코드와 문서 산출물이 생성된다. 이러한 소프트웨어 R&D 산출물들은 두가지로 분류할 수 있다. 첫 번째 분류는 연차 실적 계획서, 연구개발과제계획서, 연구성과보고서, 연구 노트와 같은 소프트웨어 연구 산출물들이 포함된다. 그리고 다른 분류는 소프트웨어 요구사항 명세서, 소프트웨어 설계 명세서, 소프트웨어 테스트 계획서, 프로그램 코드와 같은 소프트웨어 개발 산출물들이다. 프로젝트의 진행 방향을 확인할 때 프로그램 코드를 테스트하고 문서 산출물을 검증하는 것이 중요하다. 또한 연구 문서와 개발 산출물 사이에 완전성, 일관성 등의 관계를 확인해야 한다. 그러한 검증과 테스트는 프로젝트 관리자와 연구자들이 프로젝트를 진행하는 동안 올바르게 진행하고 있다는 확신을 준다. 그러므로 본 연구에서는 소프트웨어 R&D에서 생성되는 문서와 프로그램을 검증하는 프로세스를 제안한다. 본 프로세스는 문서 산출물을 검토하고 프로그램 코드를 테스트하는 활동으로 구성되어 있으며, Essence를 사용하여 정의된다. 그리고 본 연구에서 제안하는 프로세스의 효율성을 사례 연구를 통해 보인다.

• 센서학회지
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• 제27권3호
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• pp.192-198
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• 2018

Pulse oximetry is a non-invasive method for monitoring how much oxygenated hemoglobin is present in the blood. The principle of pulse oximetry is based on the red infrared light adsorption characteristics of oxygenated and deoxygenated hemoglobin. Even through the convenience of a pulse oximeter, its weak signal-to-noise ratio against motion artifacts and low perfusion makes it difficult to be accepted by execs devices. Several researchers have suggested the use of an adaptive noise cancellation (ANC) algorithm. They have demonstrated that ANC is feasible for reducing the effects of motion artifacts. Masimo Corporation developed a discrete saturation transformation (DST) algorithm that uses a reference signal and ANC. In commercial devices, it is very hard to escape it because Masimo's patents are very powerful and a better method is yet to be developed. This study proposes a new method that can measure noise saturation as well as accurate oxygen saturation from signals with high motion artifacts without using ANC and DST. The proposed algorithm can extract a normal signal without noise from a signal with motion artifacts. The reference signal from a pulse oximeter simulator was used for the evaluation of our proposed algorithm and achieved good results.

• 융합정보논문지
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• 제9권2호
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• pp.23-33
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• 2019

연구 개발 활동은 다양한 기술 정보의 조사 분석 및 기술 보고서 작성 활동들로 구성된다. 연구 개발 활동이 구체화되면서 이전 단계에 작성된, 또는 이전의 유사 프로젝트에서 작성된 관련 기술 문서를 참조하는 일이 많이 발생한다. 본 논문에서는 연구자가 원하는 이전 산출물의 효율적인 재사용을 가능하게 하는 재사용 추천 프레임워크인 RTRF(research task based reuse recommendation framework)를 제안한다. 제안하는 프레임워크는 기존의 유사어 기반 검색 및 재사용에 추가하여 태스크 유사도를 기반으로, 개발자의 연구와 비슷한 흐름을 가지고 있는 다른 개발자가 재사용한 문서를 추천해주어 개발자에게 필요할 수 있는 정보를 제공한다. 사례연구는 연구자들이 기존 문서를 재사용하여 기술동향보고서를 작성하는 과정에서의 효율성을 보이기 위해 수행하였다. RTRF를 이용하여 재사용을 수행하는 경우, RTRF를 이용하지 않는 경우와 비교했을 때 다른 단계의 문서 및 다른 연구분야의 문서를 더 빈번하게 재사용하는 것을 알 수 있었다. 본 논문에서 제안하는 RTRF는 개발자가 저장소에 저장되어 있는 방대한 양의 R&D 문서들 중에서 원하는 문서를 효율적으로 재사용하는 것에 큰 기여를 한다.

• 보존과학연구
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• 통권14호
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• pp.1-34
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• 1993

1. Metallurgical Properties of Iron artifacts excavated from Yangju-Mountain fortress were studied for the scientific conservation and metallurgical history of ancient Iron artifacts.2. Iron artifacts form Yangju-Mountain fortress were found to be the products of having well-established Carburizing and remelting technique in that period.3. These artifacts seem to be manufactured from very pure ores, because very pure ferrite structure and low impurity.4. Especially evidence of very suitable carburizing technic well-established and usealloying method of Fe-C system on purpose were found.5. Cast iron artifacts were found to be eutectic composition (4.31%) having lowestmelting point in Fe-C system.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1049-1052
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• 2004

In general, contrary to the CRTs with impulsive emission, liquid crystal displays have motion artifacts such as blurring. ghost image, decrease of dynamic CR(contrast ratio), and stroboscopic motion due to hold type driving method. In this paper, to improve motion picture quality of LCDs. impulsive driving method of black data insertion was applied to the OCB mode which is well known for its fast LC response time and wide viewing angle properties. Subject evaluation was carried out with CRT, TN, SIPS(Super IPS). and impulsive driving OCB. Moving picture image quality near CRT was obtained in impulsive OCB driving mode

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.92-97
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• 2006

Motion artifact of Display devices has a huge interest from industries and users recently. Among those artifacts, color break up (CBU) is one of the key degrading characteristic in field sequential type displays. Unfortunately, there are no objective measurement methods for CBU. Here we introduce two different kinds of CBU and its measurement methods. The CBU characteristic of LCD, DLP, and PDP was measured and compared.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1573-1576
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• 2008

A simulation system is developed to calculate the apparent motion-induced image from a sequence of temporal luminance transitions, while using the properties of the human visual system. Based on the simulation method, both edge (moving block) and detail degradation (line spreading, grating, sinusoidal pattern), and also color aberration are discussed.

• 한국군사과학기술학회지
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• 제12권3호
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• pp.290-298
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• 2009

This paper proposes a novel process which can develop the system requirements in defense R&D programs. As the weapon systems become more complicated, the success and effectiveness of R&D outcome heavily depend on the application and tailoring of systems engineering process and methods. And, the accuracy and quality of system requirements are essential prerequisite to leverage the systems engineering process. To produce the artifacts of systems engineering such as OCD, ORD, and the systems requirements, the system user can write out requirement document using the proposed implementation process and templates without expending heavy work loads.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.131-133
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• 2003

In this papers, it will be introduced that power quality analysis software design including investigation of mutual relation between power quality data and mechanism for getting data from power quality database according as based on object-oriented methodology. The UML which is only a language and so is just part of a software development, may be used to visualize, specify, construct, and document the artifacts of software-intensive system.