• Journal of Communications and Networks
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• v.13 no.1
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• pp.70-76
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• 2011

This paper presents the unified user equipment (UE) baseband modulation and demodulation (modem) hardware platform architecture to support multiple radio access technologies. In particular, this platform selectively supports two systems; one is HEDGE system, which is the combination of third generation partnership project (3GPP) Release 7 high speed packet access evolution (HSPA+) and global system for mobile communication (GSM)/general packet radio service (GPRS)/enhanced data rates for GSM evolution (EDGE), while the other is LEDGE system, which is the combination of 3GPP Release 8 long term evolution (LTE) and GSM/GPRS/EDGE. This is done by applying the flexible pin multiplexing scheme to a hardwired pin mapping process. On the other hand, to provide stable connection, high portability, and high debugging ability, the stacking structure is employed. Here, a layered board architecture grouped by functional classifications is applied instead of the conventional one flatten board. Based on this proposed configuration, we provide a framework for the verification step in wireless cellular communications. Also, modem function/scenario test and inter-operability test with various base station equipments are verified by system requirements and scenarios.

• Aerospace Engineering and Technology
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• v.10 no.2
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• pp.1-10
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• 2011

This is a comparative study of three inertia navigation units and focuses on the verification of reliability about GPS/INS for the SmartUAV(DGNS). Those GPS/INS have been tested using a manned aircraft and an automobile. The comparative aspect of units include details about the GPS positions and the inertia sensor performance. With the flight scenario, the DGNS guarantees the reliability of the navigation operation and performs the flight test for the development of the SmartUAV.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.754-756
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• 2005

RFID(Radio Frequency Identification) is used to describe a system that transmits the identity of an object or person wirelessly using radio waves. RFID is recognized as a key technology of USN(Ubiquitous Sensor Network). ISO/IEC JTC1 and EPCglobal are developing RFID related standards for global supply chain management. RFID is an important solution not only for the supply chain management, but also for USN and future services. Recently, mobile RFID which provide various services using RFID reader in mobile phone, is being standardized in Korea. In this paper, we analyze trends of RFID standardization activities in ISO/IEC JTC1 and EPCglobal and mobile RFID, and propose an convergence scenario of IPv6 and RFID.

• Structural Engineering and Mechanics
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• v.50 no.5
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• pp.617-633
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• 2014

Because the elevated temperature degrades the mechanical properties of materials used in containments, the global behavior of containments subjected to the internal pressure under high temperature is remarkably different from that subjected to the internal pressure only. This paper concentrates on the nonlinear finite element analyses of the nuclear power plant containment structures, and the importance for the consideration of the elevated temperature effect has been emphasized because severe accident usually accompanies internal high pressure together with a high temperature increase. In addition to the consideration of nonlinear effects in the containment structure such as the tension stiffening and bond-slip effects, the change in material properties under elevated temperature is also taken into account. This paper, accordingly, focuses on the three-dimensional nonlinear analyses with thermal effects. Upon the comparison of experiment data with numerical results for the SNL 1/4 PCCV tested by internal pressure only, three-dimensional analyses for the same structure have been performed by considering internal pressure and temperature loadings designed for two kinds of severe accidents of Saturated Station Condition (SSC) and Station Black-out Scenario (SBO). Through the difference in the structural behavior of containment structures according to the addition of temperature loading, the importance of elevated temperature effect on the ultimate resisting capacity of PCCV has been emphasized.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.968-978
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• 2017

Three small-break loss-of-coolant accident (SBLOCA) tests with safety injection pumps were carried out using the integral-effect test loop for SMART (System-integrated Modular Advanced ReacTor), i.e., the SMART-ITL facility. The types of break are a safety injection system line break, shutdown cooling system line break, and pressurizer safety valve line break. The thermal-hydraulic phenomena show a traditional behavior to decrease the temperature and pressure whereas the local phenomena are slightly different during the early stage of the transient after a break simulation. A safety injection using a high-pressure pump effectively cools down and recovers the inventory of a reactor coolant system. The global trends show reproducible results for an SBLOCA scenario with three different break locations. It was confirmed that the safety injection system is robustly safe enough to protect from a core uncovery.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.951-959
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• 2021

The study investigated the effect of food safety knowledge, food safety trust and the factors influencing organic food purchase intention in the 'new normal' of the COVID-19 pandemic. The study employed non-contrived and cross-sectional methods. The data was collected in Malaysia using convenience sampling. A total of 330 valid questionnaires were analyzed using Structural Equation Modelling (SEM) and PROCESS for hypothesis testing. The study revealed a significant relationship involving food safety knowledge on personal attitude, perceived social pressure, and perceived autonomy. Moreover, organic food purchase intention was found to be influenced by personal attitude, perceived social pressure, and perceived autonomy. Interestingly, trust in organic food safety moderated the relationship between perceived autonomy and organic food purchase intention. The study proved valuable for stakeholders and organic food producers to understand the 'new normal' COVID-19 market scenario for a sound understanding of the market and the sustainability of the organic food industry. A new research framework is proposed and validated, related to individual purchase decision in global health issues which is limited in current literature. Hence, the study contributed to a better comprehension of green consumerism mainly in the Asian market.

• Safety and Health at Work
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• v.12 no.4
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• pp.452-461
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• 2021

Background: The prevailing global work scenario and deteriorating health facilities in economies indulge the risk perspective in the labor market model. This is the reason that the risk factor is cautiously attributed to wages and labor market efficiencies specifically in developing and emerging economies. In this respect, Occupational Injuries of Workers (OIW) is considered essential to demonstrate the risk and Occupational Health and Safety (OHS) setups given the constraints of the labor. Intuitively, the prime objective of this study is to make an assessment of the labor market considering the OIW through the indicators of industry division, employment status, occupational distribution, adopted treatment, gender and regionality. Methods: The assessment strategy of the study has been categorized into trend analysis and Index Value Calculation (IVC) segments employing the data from 2001 to 2018. Results: The pattern of the selected indicators of the OIW has been observed in the available data while the IVC estimations are considered through time and reference categories. The findings of both exercises revealed absolute and relative heterogeneities at both industry and occupational levels. Conclusion: The consistency for gender and regional distribution of both assessments points out the need for effective policy initiatives. The study suggests separate analyses of industry and occupations for a better understanding of the OHS setups and up-gradation in Pakistan.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.3
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• pp.93-102
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• 2021

The dynamic characterization of a three-story auxiliary building in a nuclear power plant (NPP) constructed with a monolithic reinforced concrete shear wall is investigated in this study. The shear wall is subjected to a joint-research, round-robin analysis organized by the Korea Atomic Energy Research Institute, South Korea, to predict seismic responses of that auxiliary building in NPP through a shake table test. Five different intensity measures of the base excitation are applied to the shaking table test to get the acceleration responses from the different building locations for one horizontal direction (front-back). Simultaneously to understand the global damage scenario of the structure, a frequency search test is conducted after each excitation. The primary motivation of this study is to develop a nonlinear numerical model considering the multi-layered shell element and compare it with the test result to validate through the modal parameter identification and floor responses. In addition, the acceleration amplification factor is evaluated to judge the dynamic behavior of the shear wall with the existing standard, thus providing theoretical support for engineering practice.

• Clinical and Experimental Pediatrics
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• v.63 no.12
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• pp.477-482
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• 2020

The childhood obesity pandemic has emerged as an important public health problem in many countries. Obese children are likely to become obese adults, and adult obesity is associated with an increased risk of morbidity. Therefore, controlling the childhood obesity epidemic has become a top public health priority worldwide. The current coronavirus disease 2019 (COVID-19) pandemic may significantly impede this important mission and constitute an unprecedented tragedy in the global battle against childhood obesity. This manuscript presents evidence that the COVID-19 pandemic will aggravate the childhood obesity epidemic and lead to significant weight gain in school children by creating an unprecedented obesogenic environment. Within the last few months, many countries took uncompromising measures in response to the COVID-19 pandemic, including school closures and quarantine. While these steps are often necessary to ensure infection control, they may have a significant negative effect on children's mental and physical health. Physical, nutritional, and psychosocial factors that promote obesity in children during this special situation complementarily contribute to an unprecedented obesogenic environment. Large-scale quarantine and home confinement will impose new and unfamiliar stressors on children, thereby worsening the childhood obesity epidemic. Most importantly, adverse childhood events resulting from a predicted increase in domestic violence within the next few months will significantly contribute to this concern. The scenario presented in this review is of paramount public health importance and must be considered during future pandemic planning. Involved stakeholders, including governments, schools, and families, must make all possible efforts to minimize the impact of the COVID-19 epidemic on childhood obesity.

• Progress in Superconductivity and Cryogenics
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• v.24 no.2
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• pp.27-38
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• 2022

Urban air mobility (UAM) has recently attracted lots of attention as a solution to urban centralization and global warming. Electric vertical take-off and landing (eVTOL) is a concept that emerges as one of the promising and clean technologies for UAM. There are two difficult challenges for eVTOL aircraft to solve. One is how to improve the weight efficiency of aircraft, and the other is how to complete long-range missions for UAM's flight scenarios. To approach these challenges, we propose a consolidated concept design of battery-fuel cell hybrid tiltrotor aircraft with a liquid hydrogen (LH₂) fuel tank. The efficiency of a battery-fuel cell hybrid powertrain system on the designed eVTOL aircraft is compared to that of a battery-only powertrain system. This paper shows how much payload can increase and the flight scenario can be improved by hybridizing the battery and fuel cell and presenting a detailed concept of a cryogenic storage tank for LH₂.