• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.305-308
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• 2002

More complex radiotherapy techniques using multi leaf collimation(MLC) such as intensity-modulated radiation therapy(IMRT) has been increasing the significance of verification of leaf position and motion. Due to the reliability and robustness, quality assurance(QA) of MLC is usually performed with portal films. However, the advantage of ease of use and capability of providing digital data of electronic portal imaging devices(EPIDs) have attracted many attentions as alternatives of films for routine quality assurance in spite of the concerns about their clinical feasibility, efficacy, and the cost to benefit ratio. In our work, the method of routine QA of MLC using electronic portal imaging(EPI) was developed. The verification of availability of EPI images for routine QA was performed by comparison with those of the portal films which were simultaneously obtained when radiation was delivered and known prescription input to MLC controller. Specially designed test patterns of dynamic MLC were applied to image acquisition. Quantitative off-line analysis using edge detection algorithm enhanced the verification procedure in addition to on-line qualitative visual assessment. In conclusion, the EPI is available enough for routine QA with the accuracy of portal films.

• Korean Journal of Optics and Photonics
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• v.4 no.1
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• pp.90-100
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• 1993

A computer routine for personal computer(PC/AT class) is developed to analysize the mode characteristics of silica based optical waveguides whose cross sections are of semi circular and other typical shapes. The basic algorithm used in the routine is to convert the wave equation into a matrix equation by expanding the wave function in terms of simple harmonic functions. The matrix elements are a set of overlap integrals of sinusoidal funtions with appropriate weight given by the distribution of refractive index over the waveguide cross section. The eigenvectors and eigenvalues of the matrix is then computed via diagonalization. We explain some practical problems that arises when implementing the algorithm into the routine. By using this routine we analyze the mode characteristics of silica based optical waveguides of semi circular and some other typical cross sections.

• The Journal of Information Systems
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• v.30 no.1
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• pp.105-121
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• 2021

Purpose Today, through digital services, many people enjoy a conveient and comfortable life. Nevertheless, it is easy to find people in our daily lives who are buried in work without any payment that we did not do before digital services. Such un-payed works under digital environment are called digital shadow works. The purpose of this study is to classification and dynamics of digital shadow works and to suggest research direction. Design/methodology/approach Based on two dimension, voluntary participation ('should' type and 'want' type) and work orientation (management-operation), digital shadow works were classified into four categories - chore, makeup, routine, and quest. Findings In digital shadow work there are four types of dynamics - routine and quest, makeup and chore, makeup and quest, and quest and actions in offline. According to the classification and analysis of dynamics, three research directions in digital shadow work are suggested and discussed- digital shadow works operation mechanism considering dynamics, expansion of existing user theories based on survey method by digital shadow works and social influences by digital shadow works.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.425-434
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• 2008

Dopamine transporter imaging is useful in the diagnosis of Parkinson's disease and the most successful technique in the clinical use of neuroreceptor imaging. Recently, several radiopharmaceuticals including I-123 FP-CIT, Tc-99m TRODAT, and F-18 FP-CIT for dopamine transporter imaging have been approved for the routine clinical use in several European countries, Taiwan and Korea, respectively. This review summarized the practical issue for the routine clinical examination of dopamine transporter imaging.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.1050-1055
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• 2001

A software for prediction of apartment noise level ihas been improved. The program is based on the ray tracing technique which has been widely used in the environmental noise analysis and prediction. Especially for prediction of environmental noise in apartment complex, this program is advanced in the graphics routine by bilinear interpolation. In this paper, we analyze the railway noise distribution in apartment environment and develop a 3D graphics routine for illustrating the noise level.

• The Journal of Information Systems
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• v.29 no.2
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• pp.221-242
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• 2020

Purpose This study collects data of the recently activated online black market and analyzes it to present a specific method for preparing for a hacking attack. This study aims to make safe from the cyber attacks, including hacking, from the perspective of individuals and businesses by closely analyzing hacking methods and tools in a situation where they are easily shared. Design/methodology/approach To prepare for the hacking attack through the online black market, this study uses the routine activity theory to identify the opportunity factors of the hacking attack. Based on this, text mining and social network techniques are applied to reveal the most dangerous areas of security. It finds out suitable targets in routine activity theory through text mining techniques and motivated offenders through social network analysis. Lastly, the absence of guardians and the parts required by guardians are extracted using both analysis techniques simultaneously. Findings As a result of text mining, there was a large supply of hacking gift cards, and the demand to attack sites such as Amazon and Netflix was very high. In addition, interest in accounts and combos was in high demand and supply. As a result of social network analysis, users who actively share hacking information and tools can be identified. When these two analyzes were synthesized, it was found that specialized managers are required in the areas of proxy, maker and many managers are required for the buyer network, and skilled managers are required for the seller network.

• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.313-318
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• 2023

Purpose: Globally, 25 million children were either unvaccinated or under-vaccinated in year 2021. Among them, India had the highest number of children unvaccinated. Studies have shown impact of coronavirus disease 2019 (COVID-19) pandemic on routine health-care services. Present study aimed to estimate the impact of COVID-19 on utilization of routine immunization services during years 2020 and 2021 in tertiary-care facility. Materials and Methods: Record based descriptive analytic study was conducted at pediatric tertiary-care hospital, Jaipur. Data of children vaccinated as per the National Immunization Schedule for the period January 2019 to December 2021 were retrieved from the immunization records. Doses administered were assessed as a proxy measure of vaccine coverage. The vaccination trends of 2020 and 2021 were compared assuming base year 2019. Unpaired t-test of significance and Pearson correlation was used for correlation analysis. Results: There was significant drop in the vaccine counts after emergence of COVID-19 pandemic. In year 2020 and 2021, mean monthly vaccine count was 2,190±715.1 and 2,305±393.2, respectively, in which maximum drop was in April 2020 (-79.12%) and May 2021 (-57.16%) when it was compared with matched month of base year. There was negative correlation between percent change in vaccine count and COVID-19 cases in 2020 (r=-0.057, p=0.861) and 2021 (r=-0.827, p=0.001) as compared to year 2019. Conclusion: Study concludes that there was a significant gap in utilization of routine immunization services during the COVID-19 pandemic. This necessitates planning and management of routine immunization services in-case of future pandemics to avoid resurgence of vaccine-preventable diseases in the Rajasthan.

• International Journal of Aeronautical and Space Sciences
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• v.10 no.2
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• pp.23-33
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• 2009

The inherent aeromechanical complexity of a rotor system necessitated the comprehensive analysis code for helicopter rotor system. In the present study, an aerodynamic analysis module has been developed as a part of rotorcraft comprehensive program. Aerodynamic analysis module is largely classified into airload calculation routine and inflow analysis routine. For airload calculation, quasi-steady analysis model is employed based on the blade element method with the correction of unsteady aerodynamic effects. In order to take unsteady effects - body motion effects and dynamic stall - into account, aerodynamic coefficients are corrected by considering Leishman-Beddoes's unsteady model. Various inflow models and vortex wake models are implemented in the aerodynamic module to consider wake induced inflow. Specifically, linear inflow, dynamic inflow, prescribed wake and free wake model are integrated into the present module. The aerodynamic characteristics of each method are compared and validated against available experimental data such as Elliot's induced inflow distribution and sectional normal force coefficients of AH-1G. In order to validate unsteady aerodynamic model, 2-D unsteady model for NACA0012 airfoil is validated against aerodynamic coefficients of McAlister's experimental data.

• International Commerce and Information Review
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• v.9 no.4
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• pp.395-413
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• 2007

The main purpose of this study is to analyze the relationships between the R&D characteristics and R&D performance for Korean enterprises. We divided R&D performance into technological and business launching performance and analyzed four R&D characteristics' effect on the performance. The empirical analysis results can be summarized as follows: First, R&D characteristics of enterprises show a strong relationship with R&D performance in the case of R&D process control. Second, firm capability and information routine positively affect to technological performance at 0.1 significant level but not showing significance in the case of business launching performance. Third, managerial support negatively affects to technological performance but dose not show statistical significance. Its effect on business launching performance, however, shows positive and significant effect. This result is expected to be highly suggestive for establishing the effective R&D strategies of enterprises and also the relevant overseas marketing plan to support R&D planning.

• Research in Mathematical Education
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• v.15 no.2
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• pp.127-140
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• 2011

"Statistical literacy" is important to be an effective citizen ([Gal, I. (2005). Towards "probability literacy" for all citizens: Building blocks and instructional dilemmas. In: G. A. Jones (Ed.), Exploring probability in school: Challenges for teaching and learning (pp. 39-63). New York: Springer]). Probability and statistics has been connected with real context and can be used to stimulate students' creative abilities. This study aims at identifying the extent that textbooks in three countries include experimental probability concepts and non-routine, open-ended, application and contextual problems. How well textbooks reflect real application situations is important in the sense that students can employ probability concepts when solving real world problems. Results showed that three textbook series did not mention experimental probability. Furthermore, all of text-books had more routine, close-ended, knowing, and non-contextual problems.