• Wind and Structures
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• v.35 no.3
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• pp.213-227
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• 2022

The design of a building is a complex process that encompasses different fields: one of the most relevant is nowadays the energetic one, which has led to the introduction of new typologies of building envelopes. Among them, the Permeable Double Skin Façades (PDSF) are capable to reduce the solar impact and so to improve the energetic performances of the building. However, the aerodynamic characterization of a building with a PDSF is still little investigated in the current literature. The present paper proposes an experimental study to highlight the modifications induced by the outer porous façade in the aerodynamics of a building. A dedicated wind tunnel study is conducted on a rigid model of a prismatic high-rise building, where different façade configurations are tested. Specifically, the single-layer façade is compared to two PDSFs, the former realized with perforated metal and the latter with expanded metal. Outcomes of the tests allow estimating the cladding loads for all the configurations, quantifying the shielding effects ascribable to the porous layers that are translated in a significant reduction of the design pressure that could be up to 50%. Moreover, the impact of the PDSFs on the vortex shedding is investigated, suggesting the capability of the façade to suppress the generation of synchronised vortices and so mitigate the structural response of the building.

• Structural Engineering and Mechanics
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• v.82 no.3
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• pp.283-294
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• 2022

An inerter is a passive mechanical element whose inertance can be thousands of times its own physical mass. This paper discusses the application of an inerter-based passive control system, termed rotational inertial double-tuned mass damper (RIDTMD), to mitigate human-induced floor vibrations. First, the acceleration frequency response function of the floor with an RIDTMD is first derived. It is then employed to determine the optimal design parameters of the RIDTMD using the extended fixed-points technique. Based on a theoretical analysis, design-oriented empirical functions are proposed for the RIDTMD optimal parameters, whose performance for floor vibration control is evaluated by numerical examples, in which three typical human-induced load types are considered: walking, jumping, and bouncing. The results indicate that the applicability and effectiveness of the RIDTMD for human-induced floor vibration control are robust for various load types, load frequencies, and floor natural frequencies. For the same mass ratio, the RIDTMD is better than the TMD in reducing the floor vibration amplitude and improving the effective frequency suppression bandwidth, and for the same vibration suppression effect, the mass of the RIDTMD is much lighter than that of the TMD.

• Geomechanics and Engineering
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• v.30 no.5
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• pp.461-469
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• 2022

One of the most important factors that should be considered for using any ground improvement technique is the stability of stabilized soil and the durability of the provided solution for getting the required engineering properties. Generally, most of the earth structures that are constructed on clayey soils are exposing movements due to the long periods of drying or wetting cycles. Over time, environmental changes may result in swells or settlements for these structures. In order to mitigate this problem, this research has been performed on mixtures of high plasticity clay with traditional additives such as lime, cement and non-traditional additives such as polypropylene fiber. The purpose of the research is to assess the most appropriate ground improvement technique by using commercially available additives for resisting the developed desiccation cracks during the drying process and resisting the volume changes that may result during wet/dry cycles as an attempt to simulate the changes of environmental conditions. The results show that the fiber-reinforced samples have the lowest volumetric deformation in comparision with cement and lime stabilized samples, and the optimum fiber content is identified as 0.38%. In addition, the desiccation cracks were not visible on the samples' surface for both unreinforced and chemically stabilized samples. Regarding cracks resistance resulting from the desiccation process, it is observed, that the resistance is connected with the fiber content and increases with the increase of the fiber inclusion, and the optimum content is between 1% and 1.5%.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3695-3702
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• 2022

South Korea, a country that built a world-class nuclear power infrastructure, shifted to a nuclear phaseout during the previous government's reign. This shift was pursued as part of a larger task of electricity mix reform, and one of the integral motives for such reform is addressing greenhouse gas (GHG) and fine dust problems. Thus, verifying the relationships between the public's concerns about GHG/fine dust and their acceptance of nuclear power generation is essential for designing public communication strategies to revive nuclear power under the ongoing environmental regime. Our analysis using a nationwide survey sample of South Korea (N = 1009, through proportionated quota sampling method) showed that the more people are concerned about GHG and fine dust, the less they accept nuclear power. These relationships held even after controlling for the effect of a third variable-energy-related environmentalism. This finding means that despite past communication efforts positioning nuclear power as a generation source that can mitigate GHG/fine dust emissions and the widely accepted scientific evidence that supports such positioning, nuclear power in Korea is in jeopardy. Our finding provides implications for public communications and fundamental knowledge for research on the determinants of nuclear power acceptance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3680-3693
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• 2022

The handover procedure of IEEE 802.11 wireless local area networks (WLANs) introduces significant delay, which can degrade the quality of service (QoS) especially for delay-sensitive applications. Although studies have been conducted to support handover in SDN-based WLAN, there is no research to reduce the channel scanning procedure that takes up the most delay time in the handover process. The channel scanning procedure is essential to determine the appropriate access point (AP). To mitigate this problem, this paper proposes a SWITCH: SDN-WLAN integrated handover scheme for QoS-Guaranteed mobile service. In SWITCH, each AP periodically broadcasts beacon frames through different channels in a predetermined order that includes the operating channel information of the AP. This allows mobile stations (MSs) to receive the beacon frames of nearby APs, and therefore they can determine the appropriate APs for handover without the channel scanning procedure. By reporting the information of the newly moved AP to the SDN controller, a flow rule is installed in advance to provide fast handover, and packet loss is reduced by buffering data destined for MS. In addition, the proposed scheme can adaptively operate SWITCH to consider the user location and QoS requirement of flow to save radio resource overhead. Performance evaluation results demonstrate that SWITCH can reduce the handover delays, flow table utilization ratio and radio resource overhead while improving the network throughput.

• BMB Reports
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• v.55 no.6
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• pp.251-258
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• 2022

Innovative genome editing techniques developed in recent decades have revolutionized the biomedical research field. Liver is the most favored target organ for genome editing owing to its ability to regenerate. The regenerative capacity of the liver enables ex vivo gene editing in which the mutated gene in hepatocytes isolated from the animal model of genetic disease is repaired. The edited hepatocytes are injected back into the animal to mitigate the disease. Furthermore, the liver is considered as the easiest target organ for gene editing as it absorbs almost all foreign molecules. The mRNA vaccines, which have been developed to manage the COVID-19 pandemic, have provided a novel gene editing strategy using Cas mRNA. A single injection of gene editing components with Cas mRNA is reported to be efficient in the treatment of patients with genetic liver diseases. In this review, we first discuss previously reported gene editing tools and cases managed using them, as well as liver diseases caused by genetic mutations. Next, we summarize the recent successes of ex vivo and in vivo gene editing approaches in ameliorating liver diseases in animals and humans.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.3
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• pp.487-499
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• 2022

Machine learning such as deep learning have been widely used in recent years. Recently deep learning is performed in a trusted execution environment such as ARM TrustZone to improve security in edge devices and embedded devices with low computing resource. To mitigate this problem, we propose TPMP that efficiently uses the limited memory of TEE through DNN model partitioning. TPMP achieves high confidentiality of DNN by performing DNN models that could not be run with existing memory scheduling methods in TEE through optimized memory scheduling. TPMP required a similar amount of computational resources to previous methodologies.

• Journal of East Asia Management
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• v.3 no.2
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• pp.1-19
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• 2022

This study suggests an integrated theoretical framework for the relationship between political risk and multinational corporation (MNC) subsidiary's performance in the emerging market. The political risk would have a negative impact on MNC subsidiary's performance in the emerging countries that are developing in Asia, the Commonwealth of Independent States, Africa, and South America. The major reason is that political risks could generate a loss of benefit or a loss of control for MNC's subsidiary. In this study, I suggest that corporate social responsibility (CSR) strategy would be a solution to overcome various political risks. Specifically, the affiliated firms with diversified industries or greater financial resources could mitigate the negative impact of political risk than unaffiliated firms. Because they can use their tangible or nontangible asset such as information, technology, and construction in order to gain legitimacy and trust from local government, local community, and local firms in the emerging market. Finally, I claimed the costs of the affiliated firms would exceed the benefits at the initial stages, while the benefits of affiliated firms would exceed the costs over time when political risks become higher. The reason is that the trust gained from local stakeholders accumulates over time and the impact of CSR strategy would become an important solution to overcome the risks in and unstable context.

• Research in Community and Public Health Nursing
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• v.33 no.2
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• pp.228-236
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• 2022

Purpose: The purpose of this study is to demonstrate the mediating effect of happiness in the relationship between internet addiction, depression and suicidal ideation among adolescents from multicultural families. Methods: 1,065 adolescents from multicultural families who participated in the 16th (2020) Adolescent Health Behavior Survey were selected as the final subjects for the study, and were analyzed with descriptive statistics, independent t-test, ANOVA, Pearson's correlation coefficient, and stepwise multiple regression. Results: There was a fully mediating effect of happiness in the relationship between internet addiction and suicidal ideation of the adolescents from multicultural families (F=6.65, p<.001). There was a partial mediating effect of happiness in the relationship between depression and suicidal ideation of the adolescents from multicultural families (F=10.01, p<.001). Conclusion: To mitigate the suicidal ideation of adolescents from multicultural families, it is necessary to develop and apply a positive psychological treatment program that enhances happiness for adolescents from multicultural families who are experiencing internet addiction and depression.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.443-461
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• 2022

This study was conducted to assess the effects of the dietary supplementation of riboflavin (as a bile salt hydrolase [BSH] inhibitor) and Bacillus subtilis on growth performance and woody breast of male broilers challenged with Eimeria spp. Intestinal bacteria, including supplemented probiotics, can produce BSH enzymes that deconjugate conjugated bile salts and reduce fat digestion. A 3 × 2 × 2 (riboflavin × Bacillus subtilis × Eimeria spp. challenge) factorial arrangement of treatments in randomized complete block design was used. On d 14, birds were gavaged with 20× doses of commercial cocci vaccine (Coccivac^R -B52, Merck Animal Health, Omaha, NE). Dietary treatment of riboflavin and B. subtilis did not affect body weight (BW), body weight gain (BWG), and feed conversion (FCR) d 0 to 14 and overall d 0 to 41. Eimeria spp challenge reduced BWG, feed intake (FI), and increased FCR between d 14 to 28, but increased BWG and lowered FCR between d 28 to 35. There were no effects of the Eimeria spp. challenge on the overall d 0 to 41 FCR and FI, but BWG was reduced. Eimeria spp. challenge increased the abdominal fat pad weight and slight woody breast incidences on processed birds on d 42. Dietary inclusion of B. subtilis and riboflavin at tested levels did not help birds to mitigate the negative impact of Eimeria spp. challenge to enhance the growth performance.