• Journal of the Korean Society of Radiology
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• v.8 no.2
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• pp.65-74
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• 2014

This study extracts characteristics of signal by wavelet transform to prove that the Compton scattering, occurred by changed the energy, influenced a picture. We also analyzed the extracted data and evaluated how much the picture of scatter-rays was affected by a change of tube voltage. For this study, we wrote a program with MatLap which is engineering tool and evaluated with the program on variation of scattered-rays due to increased tube voltage. The evaluation result shows both CR and DR have frequency changes of high frequency area by tube voltage variations and it proved that Compton scattering influences the picture. In conclusion, according to this study indicates that DR is more sensitive to radiation with high energy than CR. Therefore, the research on DR detector needs to be advanced as actual condition of clinical setting is being changed to DR circumstance gradually. From the result of this study, we expect that assessment method of the image quality using MatLab Tool becomes the official assessment method and very useful method.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.4
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• pp.335-342
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• 2012

3D point cloud is widely used in Architecture, Civil Engineering, Medical, Computer Graphics, and many other fields. Due to the improvement of 3D laser scanner, a massive 3D point cloud whose gigantic file size is bigger than computer's memory requires efficient preprocessing and visualization. We suggest a data structure to solve the problem; a 3D point cloud is gradually subdivided by arbitrary-sized cube grids structure and corresponding point cloud subsets generated by the center of each grid cell are achieved while preprocessing. A massive 3D point cloud file is tested through two algorithms: QSplat and ours. Our algorithm, grid-based, showed slower speed in preprocessing but performed faster rendering speed comparing to QSplat. Also our algorithm is further designed to editing or segmentation using the original coordinates of 3D point cloud.

• The Journal of the Korea Contents Association
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• v.20 no.10
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• pp.401-410
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• 2020

This study is to conduct a 12-month f/u survey on changes of metabolic syndrome (MetS) components according to the resting heart rate (RHR) in patients with essential hypertension (HTN) without cardiovascular disease (CVD) complication. We used the KorHR (Korean Hypertension Registry) data and a total of 951 subjects were analyzed using the R statistical program. As a result of this study, it was found that the risk and changes of MetS components differs according to the RHR group with first and revisit hypertensive patients. Therefore, guidelines for customized RHR control for first and revisit hypertensive patients should be prepared. Also, it is necessary to prepare various interventions to control the RHR. Through this, it is intended to prevent the occurrence of CVD caused by HTN, which is a representative chronic disease, to improve the quality of life of patients and their families as well as to contribute to increasing the efficiency in the health care.

• Journal of Biomedical Engineering Research
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• v.38 no.3
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• pp.129-136
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• 2017

The exoskeleton robot is a technology developed to be used in various fields such as military, industry and medical treatment. The exoskeleton robot works by sensing the movement of the wearer. By recognizing the wearer's daily activities, the exoskeleton robot can assist the wearer quickly and efficiently utilize the system. In this study, LDA, QDA, and kNN are used to classify gait types through kinetic data obtained from subjects. Walking was selected from general walking and stair walking which are mainly performed in daily life. Seven IMUs sensors were attached to the subject at the predetermined positions to measure kinematic factors. As a result, LDA was classified as 78.42%, QDA as 86.16%, and kNN as 87.10% ~ 94.49% according to the value of k.

• Journal of the Korean Society for information Management
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• v.23 no.3 s.61
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• pp.5-21
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• 2006

In recent years, theories of image and sound analysis have been proposed to work with text retrieval systems and have progressed quickly with the rapid progress in data processing speeds. This study proposes a common representation format for multimedia documents (CRFMD) composed of both images and text to form a single data structure. It also shows that image classification of a given test set is dramatically improved when text features are encoded together with image features. CRFMD might be applicable to other areas of multimedia document retrieval and processing, such as medical image retrieval, World Wide Web searching, and museum collection retrieval.

• Journal of Korea Multimedia Society
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• v.16 no.12
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• pp.1454-1464
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• 2013

In this paper, we propose a rapid rigid registration method for the fusion visualization of intra-operative 2D XA and pre-operative 3D CTA images. In this paper, we propose a global movement estimation based on a trilateration for the fast and robust initial registration. In addition, the principal axis of each image is generated and aligned, and the bounding box of the vascular shape is compared for more accurate initial registration. For the fine registration, two images are registered where the distance between two vascular structures is minimized by selective distance measure. In the experiment, we evaluate a speed, accuracy and robustness using five patients' data by comparing the previous registration method. Our proposed method shows that two volumes can be registered at optimal location rapidly, and robustly comparing with the previous method.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.05a
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• pp.175-192
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• 2017

4차 산업혁명의 도래와 더불어 ICT 기계, ICT 금융, ICT 의료, ICT 나노 등과 같이 기술분야별 영역의 장벽이 허물어지고, 학제간 연구(Interdisplinary Research)가 일상화됨에 따라 무형자산의 가치평가시에도 융합기술의 가치평가 모형에 대한 니즈가 증대되고 있다. 특히, 기술의 매매, 현물출자, 기술금융(투자유치, 담보 보증), 인수 합병, 청산 소송 등 다양한 용도로 사용되고 있는 기술가치평가 모형은 융합기술의 입력변수 결정에 대한 체계적인 로직을 제공하지 못하고 있는 실정이다. 일반적으로 실제 거래사례가 존재할 경우, 국제가치평가기준(IVS)에 의하면 시장접근법이 우선적으로 적용될 수 있다고 권고된다. 그러나 융합기술의 이전거래를 비롯한 평가 활용사례를 수집하기도 어렵고 그렇다할 평가모델이 존재하지 않는 것이 사실이다. 융합기술에 대한 기술 및 시장의 사업화 환경을 고려하는 경우 소득접근법 기반의 평가기법이 유용하게 활용될 수 있는데, 기술수명, 매출액추정, 할인율, 산업기술요소 등의 핵심변수 결정에 관한 정형화된 로직이 존재하지 않으므로 본 고에서 융합기술 사례에 대해 실용적으로 활용가능한 변수추정 로직을 제시하고자 한다. 기술수명의 경우, 복수 개의 국제특허분류(IPC)별 피인용특허수에 따라 가중 적용하여 수명 추정을 위한 기준값을 정하며, 사업화소요기간 및 비용의 경우 평가대상 융합기술이 속하는 업종별 메타데이터값을 가중평균하여 현금흐름 추정기간을 최종 도출할 수 있다. 소득접근법에서의 매출추정, 할인율, 산업기술요소 변수 추정 이외에도 로열티공제법 적용을 위한 로열티율 결정에 있어서, 융합기술이 응용가능한 산업(업종)별 매출액 기반으로 가중 적용하여 각 변수값을 산출할 수 있다. 본 연구에서 개발된 융합기술 가치평가 모형은 향후 기술의 융복합화 특성을 반영하여 적정 가치를 산출하는 평가 가이드라인을 제공할 수 있을 것으로 기대된다.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.17-24
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• 2009

Noise evaluation for an image has been performed by root mean square (RMS) granularity, autocorrelation function (ACF), and Wiener spectrum. RMS granularity stands for standard deviation of photon data and ACF is acquired by integration of 1 D function of distance variation. Fourier transform of ACF results in noise power spectrum which is called Wiener spectrum in image quality evaluation. Wiener spectrum represents noise itself. In addition, along with MTF, it is an important factor to produce detective quantum efficiency (DQE). The proposed evaluation method using Wiener spectrum is expected to contribute to educate the concept of Wiener spectrum in educational organizations, choose the appropriate imaging detectors for clinical applications, and maintain image quality in digital imaging systems.

• The Journal of Society for e-Business Studies
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• v.22 no.1
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• pp.37-49
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• 2017

In order to maximize the efficiency and the quality of care in a hospital, hospitals in general operate by appointments. Patient no-shows or missed appointments waste the time of staffs who prepare for appointments, deprive patients of needed care, and increase burden on clinic capacity. The purpose of this study is to examine the importance and significance of factors that affect patient no-shows. The actual data of 50,000 outpatient appointments is compiled and analyzed from a VAMC in the United States with aims to identify the factors that contribute to outpatient no-shows and to draw meaningful implications. Random forest along with logistic regression analysis identify the factors affecting no-shows; appointment leadtime, show-up rate, travel distance, no-show rate in previous period, patient age, severity, complexity of disease, chronic pain, depression, drug dependence. The appointment leadtime, show-up rate, travel distance and previous no-show rate can be improved by enhancing SMS pre-notification and by improving afterwards telephone counseling. For other factors, it needs to study on the service differentiation with the characteristics of each patient group.

• Journal of Digital Convergence
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• v.12 no.6
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• pp.655-667
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• 2014

This paper has identified five major categories of the T2D patients' concerns based on an online forum where the patients voluntarily verbalized their naturally occurring emotional reactions and concerns related to T2D. We have emphasized the fact that the lexical and phrasal analysis brought to the forefront the prevailing negative reactions and desires for clear information, professional advice, and emotional support. This study used lexical and phrasal analysis based on text-mining tools to estimate the potential of using a large sample of patient conversation of a specific disease posted on the internet for clinical features and patients' emotions. As a result, the study showed that quantitative analysis based on text-mining is a viable method of generalizing the psychological concerns and features of T2D patients.