• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2935-2940
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• 2023

A polystyrene phantom was developed following the guidance of the International Atomic Energy Association (IAEA) for gamma knife (GK) quality assurance. Its performance was assessed by measuring the absorbed dose rate to water and dose distributions. The phantom was made of polystyrene, which has an electron density (1.0156) similar to that of water. The phantom included one outer phantom and four inner phantoms. Two inner phantoms held PTW T31010 and Exradin A16 ion chambers. One inner phantom held a film in the XY plane of the Leksell coordinate system, and another inner phantom held a film in the YZ or ZX planes. The absorbed dose rate to water and beam profiles of the machine-specific reference (msr) field, namely, the 16 mm collimator field of a GK Perfexion^TM or Icon^TM, were measured at seven GK sites. The measured results were compared to those of an IAEA-recommended solid water (SW) phantom. The radius of the polystyrene phantom was determined to be 7.88 cm by converting the electron density of the plastic, considering a water depth of 8 g/cm². The absorbed dose rates to water measured in both phantoms differed from the treatment planning program by less than 1.1%. Before msr correction, the PTW T31010 dose rates (PTW Freiberg GmbH, New York, NY, USA) in the polystyrene phantom were 0.70 (0.29)% higher on average than those in the SW phantom. The Exradin A16 (Standard Imaging, Middleton, WI, USA) dose rates were 0.76 (0.32)% higher in the polystyrene phantom. After msr correction factors were applied, there were no statistically significant differences in the A16 dose rates measured in the two phantoms; however, the T31010 dose rates were 0.72 (0.29)% higher in the polystyrene phantom. When the full widths at half maximum and penumbras of the msr field were compared, no significant differences between the two phantoms were observed, except for the penumbra in the Y-axis. However, the difference in the penumbra was smaller than variations among different sites. A polystyrene phantom developed for gamma knife dosimetry showed dosimetric performance comparable to that of a commercial SW phantom. In addition to its cost effectiveness, the polystyrene phantom removes air space around the detector. Additional simulations of the msr correction factors of the polystyrene phantom should be performed.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.365-374
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• 2015

The regular quality assurance (RQA) of X-ray images is essential for maintaining a high accuracy of diagnosis. This study was to evaluate the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) of a computed radiography (CR) system for various periods of use from 2006 to 2015. We measured the pre-sampling MTF using the edge method and RQA 5 based on commission standard international electro-technical commission (IEC). The spatial frequencies corresponding to the 50% MTF for the CR systems in 2006, 2009, 2012 and 2015 were 1.54, 1.14, 1.12, and $1.38mm^{-1}$, respectively and the10% MTF for 2006, 2009, 2012, and 2015 were 2.68, 2.44, 2.44, and $2.46mm^{-1}$, respectively. In the NPS results, the CR systems showed the best noise distribution in 2006, and with the quality of distributions in the order of 2015, 2009, and 2012. At peak DQE and DQE at $1mm^{-1}$, the CR systems showed the best efficiency in 2006, and showed better efficiency in order of 2015, 2009, and 2012. Because the eraser lamp in the CR systems was replaced, the image quality in 2015 was superior to those in 2009 and 2012. This study can be incorporated into used in clinical QA requiring performance and evaluation of the performance of the CR systems.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.7
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• pp.927-932
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• 2018

The demand for beef as a protein source is increasing worldwide, although in most countries beef accounts for considerably less than half of total meat consumption. Beef also provides a highly desirable eating experience in developed countries and, increasingly, in developing countries. The sustainability of beef production has different meanings in the various geographical and socio-economic regions of the world. Natural resources including land mass and uses, rainfall and access to livestock feed, and the robustness of the economy are major determinants of the perception of beef sustainability. In this overview of the 2016 International Symposium on "Future Beef in Asia" and this subsequent Special Edition of the Asian-Australasian Journal of Animal Sciences on "Current Situation and Future Prospects for Global Beef Production", the contributions have been grouped into the following categories: Countries in Southeast Asia; Europe; and Countries producing highly marbled beef for export and/or domestic consumption. They also include reference to Special Topics including marbled beef production, and use of "omics" technologies to enhance beef quality assurance. Among these broad categories, notable differences exist across countries in the production and marketing of beef. These reflect differences in factors including natural resource availability and climate, population size, traditional culture and degree of economic development including industrial and technological developments. We trust that the International Symposium and this Special Edition on Current Situation and Future Prospects for Global Beef Production, the contents of which that are briefly summarized in this paper, will serve as a valuable resource for the livestock industries, researchers and students with an interest in enhancing the prospects for sustainable, efficient beef production that satisfies the growing size and complexity of consumer demands and markets for beef.

• Journal of Korean Academy of Nursing Administration
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• v.22 no.1
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• pp.46-56
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• 2016

Purpose: Purpose of this study was to identify major trends of action research from 2006 to 2013 and suggest directions for activating and advancing domestic action research in nursing. Methods: A review was made of 118 action research studies in hospital settings reported in international journals. Search from PubMed, Ovid, and CINHAL was done using analysis criteria developed by the researchers. General and methodological characteristics and focus on changing outcomes of action research were analyzed. Results: The major group of researchers belonged to colleges/universities (40.7%). Methods included use of qualitative methods (61.0%), research questions (24.6%), and use of theoretical models (35.6%). Prevalent data collection methods were interviews (20.2%), and 48.3% showed more than a 1-cycle process including spiral circulation structure. Focus of changing outcomes of the 56 papers including more than 1-cycle were practice (66.1%), environment (8.9%), client-nurse (7.1%). Conclusion: Trends in action research in nursing were identified providing necessary reasons to increase action research in nursing as follows: needs of various researchers including stakeholders as well as healthcare providers, various research designs including unconstrained reflection and writing, specific presentation of adapted theoretical models and action strategies, and quality assurance for validity and reliability of research processes and outcomes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3687-3696
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• 2016

Cancer registration, an important component of cancer surveillance, is essential to a unified, scientific and public health approach to cancer prevention and control. India has one of the highest cancer incidence and mortality rates in the world. A good surveillance system in the form of cancer registries is important for planning and evaluating cancer-control activities. Cancer registration in India was initiated in 1964 and expanded since 1982, through initiation of the National Cancer Registry Program (NCRP) by the Indian Council of Medical Research. NCRP currently has twenty-six population based registries and seven hospital based registries. Yet, Indian cancer registries, mostly in urban areas, cover less than 15% of the population. Other potential concerns about some Indian registries include accuracy and detail of information on cancer diagnosis, and timeliness in updating the registry databases. It is also important that necessary data collection related quality assurance measures be undertaken rigorously by the registries to ensure reliable and valid information availability. This paper reviews the current status of cancer registration in India and discusses some of the important pitfalls and issues related to cancer registration. Cancer registration in India should be complemented with a nationwide effort to foster systematic investigations of cancer patterns and trends by states, regions and sub populations and allow a continuous cycle of measurement, communication and action.

• KIISE Transactions on Computing Practices
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• v.21 no.2
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• pp.115-120
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• 2015

The Testing Frontier Capability Assessment Model (TCAM) is based on ISO/IEC 9126, TMMi and TPI. Since ISO/IEC 9126, TMMi and TPI were made over 10 years ago, TCAM faces the problem that it can not assess and analyze the capability of small businesses that employ new software development methods or processes, for example Agile, TDD(Test Driven Development), App software, and Web Software. In this paper, a method to improve the problem is proposed. The paper is composed of the following sections: 1) ISO/IEC 9126, ISO/IEC 25010 and ISO/IEC/IEEE 29119 part 2 review 2) TCAM review 3) software product quality perspective comparison, and analysis between ISO/IEC 9126, ISO/IEC 25010 and TCAM 4) comparison, and analysis between ISO/IEC/IEEE 29119 part2 and TCAM and 5) proposal for the improvement of TCAM.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.4
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• pp.314-322
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• 2008

Purpose: It is widely recognized that good quality control (QC) program is essential for adequate imaging diagnosis using gamma camera. The purpose of this study is to survey the current status of QC of gamma cameras in Republic of Korea for implementing appropriate nationwide quality control guidelines and programs. Methods: A collection of data is done for personnel, equipment and appropriateness of each nuclear medicine imaging laboratory's quality control practice. This survey is done by collection of formatted questionnaire by mails, emails or interviews. We also reviewed the current recommendations concerning quality assurance by international societies. Results: This survey revealed that practice of quality control is irregular and not satisfactory. The irregularity of the QC practice seems due partly to the lack of trained personnel, equipment, budget, time and hand-on guidelines. Conclusion: The implementation of QC program may cause additional burden to the hospitals, patients and nuclear medicine laboratories. However, the benefit of a good QC program is obvious that the hospitals can provide good quality nuclear medicine imaging studies to the patients. It is important to use least cumbersome QC protocol, to educate the nuclear medicine and hospital administrative personnel concerning QC, and to establish national QC guidelines to help each individual nuclear medicine laboratory.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.41-48
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• 2013

Waste Stone and Waste Stone Powder are recycling some cyclic aggregate only. And the greater part of Waste Stone and Waste Stone Powder are reclaining or neglecting. To solve this problem, the government is proceeding development of cementitious scagliola using waste stone and waste stone powder. However, quality standard for cementitious scagliola using waste stone and waste stone powder has not been established. So cementitious scagliola using waste stone and waste stone powder has problem of quality assurance. Therefore in this study, developed standard for Evaluating Performance of cementitious scagliola using waste stone and waste stone powder through survey of international standard.

• Journal of the Korean Society of Radiology
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• v.5 no.2
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• pp.67-72
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• 2011

Accuracy control of Linear accelerator installed in OBI is done daily and weekly and importance of accuracy multiplies exponentially at that moment. Purpose of this experiment is everyday and twice a week over a four month period (march~june) 2009 year to confirm maintenance of accuracy through Quality control of OBI. In short, measurement of exponentially multiplying accuracy of OBI and regular accuracy control was able to maintain accuracy from the center of treatment within 0.1 cm. Therefore, evaluation of exponentially multiplying accuracy using OBI accuracy control linear accelerator phantom on daily, weekly basis was confirmed.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.111-120
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• 2009

Recently, pay adjustment regulation (PAR) has been developed to induce better performing road pavements around the country. This regulation was successfully applied during rehabilitation of highway flexible pavements for the first time, and their results are the focus of this paper. For highway pavements, a lot has been defined by typical amount of works a day. This lot was further divided into several sublots depending on field conditions. According to AASHTO Quality Assurance Guide Specification, pay factors for each lot were statistically determined with field measurements of five performance indicators. And composite pay factors were calculated by accounting for the impact of individual performance indicators on a long-term performance of pavement. In 2008, the PAR was tested with asphalt overlays conducted at all six local headquarters of Korea Expressway Corporation. Also, concerns raised during implementation are discussed in this paper. Limited data used in this study showed that if all performance indicators fall within the construction limits with less variances final construction costs may increase by 50%, whereas 10% reduction in construction costs could be necessary if key performance indicators such as density do not meet the construction quality requirements.