• Journal of Korean Neurosurgical Society
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• v.56 no.5
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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.

• Journal of Internet Computing and Services
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• v.17 no.2
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• pp.39-47
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• 2016

In software R&D artifacts including documents and program code are produced. There are two kinds of software R&D artifacts: Research artifacts and development artifacts. Research artifacts include software R&D planning document, annual report, final report, research note and so on. Software development artifacts include software requirements, software design description, testing plan, test report, and program code. It is important to verify the documents and to test code to check the direction of the R&D. Moreover, we should check relationships as such completeness and consistency between research and development artifacts. The verification and testing help project manager and researchers understand what they do during software projects. Therefore, in this study, we present a process to verify documents and program in software R & D. In the process we check documents produced in software R&D and test program code. We describe the process by using Essence elements including alpha, activity, and competency. We present a case study to show the effectiveness of the process.

• Journal of Sensor Science and Technology
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• v.27 no.3
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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.

• Journal of Convergence for Information Technology
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• v.9 no.2
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• pp.23-33
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• 2019

Research and development(R&D) activities consist of analytical survey and state-of-the-art report writing for technical information. As R & D activities become more concrete, it often happens that they refer to related technical documents that were created in previous steps or created in previous similar projects. This paper proposes a research-task based reuse recommendation framework(RTRF), which is a reuse recommendation system that enables researchers to efficiently reuse the existing artifacts. In addition to the existing keyword-based retrieval and reuse, the proposed framework also provides reusable information that researchers may need by recommending reusable artifacts based on task similarity; other developers who have a similar task to the researcher's work can recommend reusable documents. A case study was performed to show the researchers' efficiency in the process of writing the technology trend report by reusing existing documents. When reuse is performed using RTRF, it can be seen that documents of different stages or other research fields are reused more frequently than when RTRF is not used. The RTRF may contribute to the efficient reuse of the desired artifacts among huge amount of R&D documents stored in the repository.

• 보존과학연구
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• s.14
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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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• 2004.08a
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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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• 2006.08a
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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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• 2008.10a
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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.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.3
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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.

• Proceedings of the KIEE Conference
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• 2003.11a
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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.