• Korean Journal of Radiology
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• v.23 no.4
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• pp.402-412
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• 2022

Objective: To evaluate the image quality and lesion detectability of lower-dose CT (LDCT) of the abdomen and pelvis obtained using a deep learning image reconstruction (DLIR) algorithm compared with those of standard-dose CT (SDCT) images. Materials and Methods: This retrospective study included 123 patients (mean age ± standard deviation, 63 ± 11 years; male:female, 70:53) who underwent contrast-enhanced abdominopelvic LDCT between May and August 2020 and had prior SDCT obtained using the same CT scanner within a year. LDCT images were reconstructed with hybrid iterative reconstruction (h-IR) and DLIR at medium and high strengths (DLIR-M and DLIR-H), while SDCT images were reconstructed with h-IR. For quantitative image quality analysis, image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured in the liver, muscle, and aorta. Among the three different LDCT reconstruction algorithms, the one showing the smallest difference in quantitative parameters from those of SDCT images was selected for qualitative image quality analysis and lesion detectability evaluation. For qualitative analysis, overall image quality, image noise, image sharpness, image texture, and lesion conspicuity were graded using a 5-point scale by two radiologists. Observer performance in focal liver lesion detection was evaluated by comparing the jackknife free-response receiver operating characteristic figures-of-merit (FOM). Results: LDCT (35.1% dose reduction compared with SDCT) images obtained using DLIR-M showed similar quantitative measures to those of SDCT with h-IR images. All qualitative parameters of LDCT with DLIR-M images but image texture were similar to or significantly better than those of SDCT with h-IR images. The lesion detectability on LDCT with DLIR-M images was not significantly different from that of SDCT with h-IR images (reader-averaged FOM, 0.887 vs. 0.874, respectively; p = 0.581). Conclusion: Overall image quality and detectability of focal liver lesions is preserved in contrast-enhanced abdominopelvic LDCT obtained with DLIR-M relative to those in SDCT with h-IR.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.107-115
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• 2020

Purpose: This study aims to systematically review the dual-task evaluation applied to the screening of mild cognitive impairment. It also aims to present various evaluation items and results analysis methods for dual tasks applied to patients with mild cognitive impairment. Methods: We conducted a systematic search of published studies in PubMed databases and KISS from January 2000 to August 2020 using the main keywords such as "Dual task," "Mild Cognitive impairment," "Elderly," and "Screening." We selected a total of 10 studies for the analysis from 1314 searched articles. Results: We analyzed the qualitative level of 10 studies that were nonrandomized two-group studies with evidence level II (100.0%). These results suggest that the evidence level of the studies was high. We analyzed 10 studies and identified 12 motor tasks and 19 cognitive tasks. Walking was the most commonly used evaluation motor task and counting backward by ones and naming animals were the most commonly used evaluation cognitive tasks. Moreover, the velocity speed was the most used result analysis method. The results indicate that there were significant differences in dual-task performance between patients with normal and mild cognitive impairment. Conclusion: The results of this study can be used as a basis for the selection of dual-task evaluation items and methods of analyzing the results for screening mild cognitive impairment. Furthermore, they are expected to be used for research on the development of dual-task evaluation tools. It is necessary to compare and analyze the usage trends of dual-task evaluation by cultural differences in future studies.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.1
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• pp.119-133
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• 2024

As a result of significant investments by the government in promoting public technology commercialization and fostering a venture startup ecosystem, there have been quantitative achievements, such as the registration of over 1,600 Innopolis Start-ups since 2006, generating a total revenue of 1.1 trillion won as of 2021. However, these achievements have been overshadowed by critical qualitative challenges, including a continuous decline in average revenue per Innopolis Start-up. This led to a focus on whether managers' technological and market orientations affect business performance. This study aims to provide insights into improving the qualitative growth of Innopolis Start-ups by analyzing the effects of technological and market orientations on business performance, as well as the moderating effects of adjusting marketing and research and development (R&D) costs on this relationship. Through prior research and empirical analysis, this study derives three main findings. First, technological excellence and innovation significantly influence the business performance of Innopolis Start-ups, while technological intensity does not. Second, customer orientation and competitive orientation significantly impact business performance, whereas entry barriers as a single factor do not. Third, adjusting marketing and R&D costs, as controlled variables obtained through general situations, has no direct impact on other variables. However, it interacts with entry barriers, influencing financial business performance, with R&D costs exhibiting a negative buffering effect and marketing costs showing a positive enhancing effect. This study confirms that both technological and market orientations directly influence the business performance of Innopolis Start-ups, thus being crucial factors affecting their growth. Moreover, it establishes that investments in marketing and R&D play significant roles in alleviating initial entry barriers and enhancing financial performance. Consequently, it underscores the importance of reinforcing technological and market orientations tailored to the characteristics of Innopolis Start-ups. Additionally, it proposes five theoretical contributions: strengthening institutional support systems for technology commercialization and innovation, improving qualitative evaluation criteria during the selection process of Innopolis Start-ups, conducting comprehensive analyses of technological and market aspects during startup selection, enhancing support for marketing education and consulting for smooth market entry, and supporting expenditure strategies and milestone setting tailored to the industrial characteristics of individual Innopolis Start-ups.

• Management & Information Systems Review
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• v.38 no.1
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• pp.63-81
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• 2019

In order to overcome the disadvantages of banner ad, pop-up ad, interstitial ad, which are existing web advertisement forms, native ad is actively utilized. Native advertising is considered to be a useful advertising technique in that it can reduce users' rejection and attract attention. However, in recent years, there have been a lot of fake news and fake contents that have turned articles or video contents into advertisements. The purpose of this study is to understand how firms can coordinate and control native advertisements in a rational way. For this analysis, we conducted a survey of 308 social media users using quota sampling method. As a result of the verification, it was found that the more negative the perception of the evaluation of the advertisement, the less the level of persuasion about the advertisement and the negative impact on the website where the advertisement is exposed. In addition, this study examined the influence of the negative stimulus factors on the qualitative performance of the firm. As a result, it was found that source non-expert had the highest effect on skepticism on ad. Also, platform overflow has a direct effect on the evaluation of the website as well as the negative evaluation of the advertisement. Moreover, this study provides concrete implications for the subdivision market by verifying the differences between the paths according to the level of website involvement.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.4 s.247
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• pp.364-372
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• 2006

The objective of this study is to evaluate the efficiency and the prediction accuracy of developed large eddy simulation (LES) program for complex turbulent flows, such as recirculating and swirling flows. To save the computational cost, a Beowulf cluster system consisting 16 processors was constructed. The flows in backward-facing step and dump combustor were examined as representative recirculating and swirling flows. Firstly, a direct numerical simulation (DNS) for laminar backward-facing step flows was previously conducted to validate the overall performance of program. Then LES was carried out for turbulent backward-facing step flows. The results of laminar flow showed a qualitative and quantitative agreement between simulations and experiments. The simulations of the turbulent flow also showed reasonable results. Secondly, LES results for non-swirling and swirling flows in a dump combustor were compared with the results of Reynolds-averaged Navier-Stokes (RANS) using standard $k-{\varepsilon}$ model. The results show that LES has a better performance in predicting the mean axial and azimuthal velocities, comer recirculation zone (CRZ) and center toroidal recirculation zone (CTRZ) than those of RANS. Finally, it was examined the capability of LES for the description of unsteady phenomena.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.3
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• pp.134-146
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• 2011

This paper suggests the product supply process model based on the store and production capacity, assortment planning and quick response for fast fashion retailers with BPMN. In the fast fashion industry, the standardized business process model is required to respond quickly market trends and customer requirements based on the quantitative and qualitative criteria. Thus we define the product supply processes which incorporate forecasting and assortment plan, cost and profitability of the production, store capacity based on the visual merchandising, and production capacity of the fast fashion retailers. Also we design the key performance indicators to evaluate the effectiveness of these product supply processes. The product supply process model for the fast fashion has great significance in embracing the fast fashion product development process because it presents the holistic view of the product supply process of the fast fashion and provides a performance evaluation mechanism. A case study shows that adopting the processes, a Korean fast fashion company achieves improvement in various performance indicators.

• Journal of IKEEE
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• v.27 no.3
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• pp.296-302
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• 2023

As Multimedia industry has evolved, it has become possible to display resolutions in various formats. Therefore, the performance of a scaler algorithm that converts resolutions while maintaining high quality and its hardware implementation are important. Considering the hardware design of an image up/down scaler, this paper proposes a combinatorial scaler algorithm that uses modified bilinear interpolation in the vertical direction and bicubic interpolation in the horizontal direction to reduce the line memory burden. Through quantitative and qualitative evaluations, this paper compared the performance of the proposed algorithm with three other well-known algorithms, and also compared the hardware burden of its hardware implementation. This paper used a sinusoidal signal and eight typical images for performance evaluation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.742-756
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• 2008

Recently, it's increasing to use the applied technology related to the quantitative and qualitative growth of industry area. One of them is software to be used in industry area, and software is the most important part in using the industrial equipments. Therefore, the quality of software in the industrial devices determines the performance of the devices. At this time, it's inspired an evaluation and measurement of software quality to have within industrial equipment, and it's forming the research and development in domestic and foreign. In this paper, we constructed evaluation metrics based on ISO/IEC 12119, the International Standard for the general requirements of software and ISO/IEC 9126-2, the International Standard for the evaluation of software qualify characteristics and sub-characteritics, and for this accomplishment, It has been designed and developed industrial software international standard compatible approval system which approve a quality based on quality test result of industrial software using the ISO/IEC 14598-6 that international standard for organization of evaluation module.

• School Mathematics
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• v.13 no.1
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• pp.127-153
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• 2011

The purpose of this study was to investigate the effect of peer tutoring on mathematical inclination and mathematical communication ability of peer tutor. For the purpose of this study, research questions were established as follows: 1. How does peer tutoring affect to the mathematical inclination of peer tutors? 2. How does peer tutoring affect to the mathematical communication ability of peer tutors? To answer the research questions, four 5th grade peer tutors were selected for qualitative case study in an elementary school located in Goyang-si, Gyeonggi-do. Before and after 11 weeks of peer tutoring in their mathematics classes, mathematical inclination, mathematical communication ability of peer tutors were examined. For qualitative analysis, peer tutors were asked to complete worksheets, self-evaluation, journal for their peer tutoring in daily basis during the experiment. By comparing the scores in mathematical inclination test and mathematical communication test before and after the treatment and analyzing the data gathered for qualitative analysis, the conclusions were drawn as follows: First, Peer tutoring has positive effects on the mathematical inclination of peer tutors. Scores for mathematical inclination of peer tutors after the treatment increased and qualitative analysis showed positive change in their attitude toward mathematics. Second, Peer tutoring has positive effects on the mathematical communication ability of peer tutors. Scores in the performance assessment for mathematical communication ability of peer tutors after the treatment increased. Also qualitative analysis showed that peer tutors tried to develop various ways to solve a problem and explained them to their peer tutee sophisticatedly.

• Korean Journal of Construction Engineering and Management
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• v.7 no.4 s.32
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• pp.154-163
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• 2006

Recently, the demand for performance evaluation and management at the industrial or corporate level has been increasing. From this perspective, this study has developed indicators to measure and compare construction company performances and we have analyzed various characteristics of those indicators. Throughout our thorough qualitative and quantitative analysis we first identified a set of indicators for performance measurement. These indicators have been shown to meet the requirements of validity, measurability, and comparability. Second, we calculated the performance index of construction companies by applying weightings of the performance categories. Then we performed correlation and regression analyses using the calculated performance index and identified the basic cause-and-effect relationships, as well as the statistical characteristics of the performance index. Drawing on the results of the analytical processes identified in this work, we discuss future research to be conducted.