• Journal of Space Technology and Applications
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• v.3 no.4
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• pp.333-341
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• 2023

This study aims to develop technology for testing and verifying the space radiation environment of miniature space components using the facilities of the domestic 100 MeV proton accelerator and the Space Component Test Facility at the Space Testing Center. As advancements in space development progress, high-performance satellites increasingly rely on densely integrated circuits, particularly in core components components like memory. The application of semiconductor components in essential devices such as solar panels, optical sensors, and opto-electronics is also on the rise. To apply these technologies in space, it is imperative to undergo space environment testing, with the most critical aspect being the evaluation and testing of space components in high-energy radiation environments. Therefore, the Space Testing Center at the Korea testing laboratory has developed a radiation testing device for memory components and conducted radiation impact assessment tests using it. The investigation was carried out using 100 MeV protons at a low flux level achievable at the Gyeongju Proton Accelerator. Through these tests, single event upsets observed in memory semiconductor components were confirmed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1441-1447
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• 2012

This study was conducted to examine the effects of gamma irradiation on the shelf-life and sensory scores of squid Sundae under accelerated storage conditions. Squid Sundae was stored at $37^{\circ}C$ for 35 days following gamma irradiation at doses of 0, 10, and 20 kGy. For total viable cell counts, control and gamma-irradiated (GI) (10 kGy) squid Sundae were already spoiled in 4 days, whereas GI (20 kGy) squid Sundae showed complete suppression of bacterial growth during storage. There were no significant changes in pH values compared to the control. The VBN and TBARS (thiobarbituric acid reactive substance) values of GI (20 kGy) squid Sundae were significantly lower than those of the control. In addition, the induction period of GI (20 kGy) squid Sundae as measured by a Rancimat showed a higher level compared to that of the control. In the sensory evaluation, there were no significant changes between the control and GI samples. These results suggest that a dose of 20 kGy is the optimum and effective dose for preservation of squid Sundae.

• Land and Housing Review
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• v.2 no.2
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• pp.111-123
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• 2011

A Ubiquitous-Ecological City (U-Eco City) is the new urban paradigm integrated with ubiquitous-city (U-City) connecting the high-tech IT technology to the urvan space with the concept of the sustainable eco-city. As a U-Eco City is attempted for the first time domestically and internationally, there is insufficient discussions for its develoment goal, planned design proposal, technology and service element and others. Even if there are plans to build up it, policy and technology, service structuring business and others, it is difficult to assess how it would bring the efficacy. Therefore, the purpose of this study is to present the indicators system to assess a U-Eco City. The results of this study revealed the following; First, the conceptual framework, which was established to achieve sustainable urban quality, can be suggested by establishing its notion of the U-Eco City. The concept of a U-Eco City as established in this study suggests that the economic development in growth-oriented level has to be conducted not only quality of urban environment but also in terms of sustainable to consider the complex impact of various development; Secondly, the developed assessment system has heightened the completeness as the evaluation index through the attitude survey. As a result of questionnaire survey with the subject of specialists and interested party of this study, the urban qualitative aspect is formulated for the stability as a relatively important aspect. For the urban continuity aspect, society, environment and economy have all similar importance, but the environment element was shown to be highest. And finally, subject area was selected on the basis of the evaluation system and the analysis was made on the basis of the implementation design plan of the area. As a result of the assessment, safety and economy have shown to be high. This is indirectly indicated for the priority in economic growth driven development plan unlike the importance of environmental continuity obtained through the attitude survey. When planning on urban development, there is a need for supplementing the environment part and it has to present the connection plan between the economic growth and environmental continuity.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.615-622
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• 2016

The 18~20G needle is used to computer tomography (CT) contrast examination. Therefore, a patient has to apply a self-administering hemostasis (conventional method: CM) and often experience bleeding in the course. Thus, we developed the new disposable transparent tourniquet (TT) for reducing. This study was to compare the usefulness between the proposed transparent tourniquet and the existing hemostatic methods. A Satisfaction survey was conducted by 50 patients and 25nurses. The survey contained the satisfaction of the convenience, safety, sanitation, and wearing sensation of transparent tourniquet. We employed face-to-face interview on 5 points likert scales. And Chi-square, paired T-test were used for the statistics verification. As for the patients, the satisfaction levels were measured for each category with the gender, age. Patients evaluation, overall satisfaction high average sore used TT and there were statistical significance by paired T-test(p<0.05). The following is the average satisfaction level for each category: $4.4{\pm}0.53$ in; $4.28{\pm}0.57$ in safety; $4.52{\pm}0.54$ in sanitation; $4.16{\pm}0.54$ in wearing sensation. So the overall satisfaction level is measured at $4.34{\pm}0.51$. As for the nurses, CT work experience and the current satisfaction with tourniquet were counted as variables. The satisfaction level for each category is: $3.8{\pm}0.7$ in; $3.6{\pm}0.68$ in safety; $3.4{\pm}0.5$ in sanitation; $3.9{\pm}0.49$ in hemostasis. The overall satisfaction level is $3.8{\pm}0.3$. Patients' satisfaction levels were very high with little difference among variables. Nurses' satisfaction levels were different with the TT depending on their work experience but their overall satisfaction was high. This TT will be a starting point to minimizing patient's inconvenience and more studies are necessary to enhance their satisfaction.

• Journal of Satellite, Information and Communications
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• v.12 no.3
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• pp.108-113
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• 2017

The OBCP called 'operator on board' is that of a procedure to be executed on-board, which can be easily be loaded, executed, and also replaced, without modifying the remainder of the FSW. The use of OBCP enhances the on-board autonomy capabilities and increases the robustness to ground stations outages. The OBCP engine which is the core module of OBCP component in the FSW interprets and executes of the procedures based on script language written using a high-level language, possibly compiled, and it is relying on a virtual machine of the OBCP engine. FSW team in KARI has studied OBCP since 2010 as FSW team's internal projects, and made some OBCP engines such as Java KVM, RTCS/C and KKOMA on ERC32 processor target only for study. Recently we have been studying ESA's OBCP standard and implementing Lua and MicroPython on LEON2-FT/AT697F processor target as the OBCP engine. This paper presents the design and implementation of Lua for the OBCP engine on AT697F processor with VxWorks RTOS, and describes the evaluation result and performance of the OBCP engine.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.47-52
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• 2011

Purpose: Facilities use own sever or mini PACS system for storage and analysis of the PET/CT data. Mini PACS can storage scan data as well as measuring SUV. Therefore, the study was performed to confirm whether or not measured SUV on mini PACS is measured equally on PET/CT workstation. Materials and Methods: In February 2011, 30 patients who were performed $^{18}F$-FDG wholebody PET/CT scan in Biograph 16, Biograph 40 and Discovery Ste 8 were enrolled. First, using each workstation, SUV in liver and aorta of mediastinum level was measured. Second, using mini PACS, SUV was measured by same method. Result: The correlation coefficient of SUV in liver between PET/CT scanner and min PACS in Biograph 16, Biograph 40, Discovery Ste 8 was 0.99, 0.98, 0.64 respectably, the correlation coefficient of SUV in aorta was 0.98, 0.98, 0.66, and these were showed positive correlation coefficient. Difference of SUV between Biograph workstation and mini PACS was not showed statistical significant difference at 5% level of significance. Difference of SUV between Discovery Ste 8 workstation and mini PACS was showed statistical significant difference at 5% level of significance. Conclusion: In case that patient was scanned by the other scanner, if the correction of SUV formula in mini PACS for each scanners is performed, mini PACS will be usefully used to provide consistently quantitative assessment.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.803-811
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• 2024

Nuclear accidents such as Fukushima Daiichi have highlighted the potential of passive safety systems to replace or complement active safety systems as part of the overall prevention and/or mitigation strategies. In addition, passive systems are key features of Small Modular Reactors (SMRs), for which they are becoming almost unavoidable and are part of the basic design of many reactors available in today's nuclear market. Nevertheless, their potential to significantly increase the safety of nuclear power plants still needs to be strengthened, in particular the ability of computer codes to determine their performance and reliability in industrial applications and support the safety demonstration. The PASTELS project (September 2020-February 2024), funded by the European Commission "Euratom H2020" programme, is devoted to the study of passive systems relying on natural circulation. The project focuses on two types, namely the SAfety COndenser (SACO) for the evacuation of the core residual power and the Containment Wall Condenser (CWC) for the reduction of heat and pressure in the containment vessel in case of accident. A specific design for each of these systems is being investigated in the project. Firstly, a straight vertical pool type of SACO has been implemented on the Framatome's PKL loop at Erlangen. It represents a tube bundle type heat exchanger that transfers heat from the secondary circuit to the water pool in which it is immersed by condensing the vapour generated in the steam generator. Secondly, the project relies on the CWC installed on the PASI test loop at LUT University in Finland. This facility reproduces the thermal-hydraulic behaviour of a Passive Containment Cooling System (PCCS) mainly composed of a CWC, a heat exchanger in the containment vessel connected to a water tank at atmospheric pressure outside the vessel which represents the ultimate heat sink. Several activities are carried out within the framework of the project. Different tests are conducted on these integral test facilities to produce new and relevant experimental data allowing to better characterize the physical behaviours and the performances of these systems for various thermo-hydraulic conditions. These test programmes are simulated by different codes acting at different scales, mainly system and CFD codes. New "system/CFD" coupling approaches are also considered to evaluate their potential to benefit both from the accuracy of CFD in regions where local 3D effects are dominant and system codes whose computational speed, robustness and general level of physical validation are particularly appreciated in industrial studies. In parallel, the project includes the study of single and two-phase natural circulation loops through a bibliographical study and the simulations of the PERSEO and HERO-2 experimental facilities. After a synthetic presentation of the project and its objectives, this article provides the reader with findings related to the physical analysis of the test results obtained on the PKL and PASI installations as well an overall evaluation of the capability of the different numerical tools to simulate passive systems.

• Journal of dental hygiene science
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• v.17 no.2
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• pp.123-133
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• 2017

The aim of this study was to analyze in depth the standardized Clinical dental hygiene curriculum of the Fones School in the United States. We investigated the clinical dental hygiene curriculum in 2015~2016 including title, credit, hours, contents, goals, competencies, and evaluation. We obtained the course syllabus and data related to each subject, for each grade, from the professors and students at the university. The goals and competencies, of the clinical dental hygiene program, which were based on the goals of the Fones School and the mission of the University of Bridgeport, were developed in accordance with the dental hygienist practice standards proposed by the American Dental Hygienists Association. The curriculum consisted of theory to teach proper dental hygiene care procedures and incorporated practical exercises that modeled an actual clinical setting. The students had to document the procedures performed for each client/patient and improve their clinical competency through discussion with the professors. Dental hygiene care should be provided for children, adolescents, adults, elderly, and patients, which includes patients with moderate or severe periodontal status. Students were evaluated by a paper test or case study presentation and their clinical evaluation was based on their clinical competency. In particular, professors evaluated students on a rotational basis, so they could evaluate the level of achievement of clinical competency of all students and find ways to improve any weaknesses. Therefore, the current study suggested that clinical dental hygiene program in Korea could be improved if based on the curriculum of Fones School in the United States.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.27-42
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• 2020

Startup accelerators have emerged as new investment entities that help early startups, which are not easy to survive continuously due to lack of funds, commercialization capabilities, and experiences. As their positive performance on early startups and the ecosystem has been proven, the number of early startups which want to receive their investment is also increasing. However, they are vaguely preparing to attract accelerators' investment because they do not have any information on what factors the accelerators consider important. In addition, researches on startup accelerators are also at an early level, so there are no remarkable prior studies on factors that decide on investment. Therefore, this study aims to help startups prepare for investment attraction by looking at what factors are important for accelerators to invest, and to provide meaningful implications to academia. In the preceding study, we derived five upper level categories, 26 lower level accelerators' investment determinants through the qualitative meta-synthesis method, secondary data analysis, observation on US accelerators and in-depth interviews. In this study, we want to derive important implications by deriving priorities of the accelerators' investment determinants. Therefore, we used AHP that are evaluated as the suitable methodology for deriving importance and priority. The analysis results show that accelerators value market-related factors most. This means that startups that are subject to investment by accelerators are early-stage startups, and many companies have not fully developed their products or services. Therefore, market-related factors that can be evaluated objectively seem to be more important than products (or services) that are still ambiguous. Next, it was found that the factors related to the internal workforce of startups are more important. Since accelerators want to develop their businesses together with start-ups and team members through mentoring, ease of collaboration with them is very important, which seems to be important. The overall priority analysis results of the 26 investment determinants show that 'customer needs' and 'founders and team members' understanding of customers and markets' (0.62) are important and high priority factors. The results also show that startup accelerators consider the customer-centered perspective very important. And among the factors related to startups, the most prominent factor was the founder's openness and execution ability. Therefore, it can be confirmed that accelerators consider the ease of collaboration with these startups very important.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.343-356
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• 2016

The Korea Radioactive Waste Agency (KORAD) has developed a dual-purpose metal cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. The metal cask was designed in compliance with international and domestic technology standards, and safety was the most important consideration in developing the design. It was designed to maintain its integrity for 50 years in terms of major safety factors. The metal cask ensures the minimization of waste generated by maintenance activities during the storage period as well as the safe management of the waste. An activation evaluation of the main body, which includes internal and external components of metal casks whose design lifetime has expired, provides quantitative data on their radioactive inventory. The radioactive inventory of the main body and the components of the metal cask were calculated by applying the MCNP5 ORIGEN-2 evaluation system and by considering each component's chemical composition, neutron flux distribution, and reaction rate, as well as the duration of neutron irradiation during the storage period. The evaluation results revealed that 10 years after the end of the cask's design life, $^{60}Co$ had greater radioactivity than other nuclides among the metal materials. In the case of the neutron shield, nuclides that emit high-energy gamma rays such as $^{28}Al$ and $^{24}Na$ had greater radioactivity immediately after the design lifetime. However, their radioactivity level became negligible after six months due to their short half-life. The surface exposure dose rates of the canister and the main body of the metal cask from which the spent nuclear fuel had been removed with expiration of the design lifetime were determined to be at very low levels, and the radiation exposure doses to which radiation workers were subjected during the decommissioning process appeared to be at insignificant levels. The evaluations of this study strongly suggest that the nuclide inventory of a spent nuclear fuel metal cask can be utilized as basic data when decommissioning of a metal cask is planned, for example, for the development of a decommissioning plan, the determination of a decommissioning method, the estimation of radiation exposure to workers engaged in decommissioning operations, the management/reuse of radioactive wastes, etc.