• Steel and Composite Structures
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• v.32 no.6
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• pp.807-819
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• 2019

In recent earthquakes, the failure of ceiling systems has been one of the most widely reported damage and the major cause of functionality interruption in some buildings. In an effort to mitigate this damage, some scholars have studied a series of ceiling systems including plaster ceilings and mineral wool ceilings. But few studies have involved the backdrop metal ceiling used in some important constructions with higher rigidity and frequency such as the main control area of nuclear power plants. Therefore, in order to evaluate its seismic performance, a full-scale backdrop metal ceiling system, including steel runners and metal panels, was designed, fabricated and installed in a steel frame in this study. And the backdrop metal ceiling system with two perimeter attachments variants was tested: (i) the ends of the runners were connected with the angle steel to form an effective lateral constraint around the backdrop metal ceiling, (ii) the perimeter attachments of the main runner were retained, but the perimeter attachments of the cross runner were removed. In the experiments, different damage of the backdrop metal ceiling system was observed in detail under various earthquakes. Results showed that the backdrop metal ceiling had good integrity and excellent seismic performance. And the perimeter attachments of the cross runner had an adverse effect on the seismic performance of the backdrop metal ceiling under earthquakes. Meanwhile, a series of seismic construction measures and several suggestions that need to be paid attention were proposed in the text so that the backdrop metal ceiling can be better applied in the main control area of nuclear power plants and other important engineering projects.

• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.410-418
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• 2019

To investigate a novel ${\beta}$-glucosidase from Bifidobacterium breve ATCC 15700 (BbBgl) to produce compound K (CK) via ginsenoside $F_2$ by highly selective and efficient hydrolysis of the C-3 glycoside from ginsenoside Rd, the BbBgl gene was cloned and expressed in E. coli BL21. The recombinant BbBgl was purified by Ni-NTA magnetic beads to obtain an enzyme with specific activity of 37 U/mg protein using pNP-Glc as substrate. The enzyme activity was optimized at pH 5.0, $35^{\circ}C$, 2 or 6 U/ml, and its activity was enhanced by $Mn^{2+}$ significantly. Under the optimal conditions, the half-life of the BbBgl is 180 h, much longer than the characterized ${\beta}$-glycosidases, and the $K_m$ and $V_{max}$ values are 2.7 mM and $39.8{\mu}mol/mg/min$ for ginsenoside Rd. Moreover, the enzyme exhibits strong tolerance against high substrate concentration (up to 40 g/l ginsenoside Rd) with a molar biotransformation rate of 96% within 12 h. The good enzymatic properties and gram-scale conversion capacity of BbBgl provide an attractive method for large-scale production of rare ginsenoside CK using a single enzyme or a combination of enzymes.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.751-760
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• 2018

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.7
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• pp.2496-2512
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• 2021

The requirements for powerful computing capability, high capacity, low latency and low energy consumption of emerging services, pose severe challenges to the fifth-generation (5G) network. As a promising paradigm, mobile edge networks can provide services in proximity to users by deploying computing components and cache at the edge, which can effectively decrease service delay. However, the coexistence of heterogeneous services and the sharing of limited resources lead to the competition between various services for multiple resources. This paper considers two typical heterogeneous services: computing services and content delivery services, in order to properly configure resources, it is crucial to develop an effective offloading and caching strategies. Considering the high energy consumption of 5G base stations, this paper considers the hybrid energy supply model of traditional power grid and green energy. Therefore, it is necessary to design a reasonable association mechanism which can allocate more service load to base stations rich in green energy to improve the utilization of green energy. This paper formed the joint optimization problem of computing offloading, caching and resource allocation for heterogeneous services with the objective of minimizing the on-grid power consumption under the constraints of limited resources and QoS guarantee. Since the joint optimization problem is a mixed integer nonlinear programming problem that is impossible to solve, this paper uses deep reinforcement learning method to learn the optimal strategy through a lot of training. Extensive simulation experiments show that compared with other schemes, the proposed scheme can allocate resources to heterogeneous service according to the green energy distribution which can effectively reduce the traditional energy consumption.

• Advances in concrete construction
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• v.11 no.5
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• pp.375-386
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• 2021

In this paper, a study of stability and health of a newly-built railway tunnel is presented. The field test was implemented to monitor the secondary lining due to the significant cracking behaviors influenced the stability and health of the tunnel structure. Surface strain gauges were installed for monitoring the status of crack openings, and the monitoring outputs demonstrated that the cracks were still in the developing stage. Additionally, adjacent tunnel and poor condition of surrounding rock were identified as the causes of the lining cracking by systematically characterizing the crack spatial distribution, tunnel site and surrounding rock conditions. Reconstruction of partial lining and reconstruction of the whole secondary lining were designed as the maintenance projects for different cracking regions based on the construction feasibility. For assessing the health conditions of the reinforced lining, embedded strain gauges were set up to continuously measure the strain and the internal force of the reconstructed structures. For the partially reconstructed lining, the outputs show the maximum tensile elongation is 0.018 mm during 227 days, which means the structure has no obvious deformation after maintenance. The one-year monitoring of full-section was implemented in the other two completely reconstructed cross-sections by embedded strain gauge. The outputs show the reconstructed secondary lining has undertaken the pressure of surrounding rock with the time passing. According to the calculated compressive and tensile safety factors, the completely reconstructed lining has been in reliable and safe condition during the past year after reinforcement. It can conclude that the aforementioned maintenance projects can effectively ensure the stability and health of this tunnel.

• Journal of the Korea Convergence Society
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• v.12 no.3
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• pp.125-132
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• 2021

This study deals with the influencing factors on flow and addiction perceived by users of Tiktok service, an SFV service platform that is expanding the market in the middle area between social media and OTT. As the number of Tiktok users increases, researchers thought that research on the cause of addiction would be necessary. Since media users lack media consumption time, they produce and share SFVs rather than long videos, and are affected by exogenous variables. In addition, attachment is divided into interpersonal relationships and attachment to services, and the path of attachment was confirmed to be connected to flow and addiction. Through this study, the researchers considered that there were theoretical and practical contributions in that the path leading to addiction of video media services was set and verified as self-exposure and attachment, flow and addiction. These research results can be applied to more diversified video-centered media services, and can be expected to be used for new media emerging in the future.

• Journal of Korea Multimedia Society
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• v.25 no.2
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• pp.374-381
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• 2022

This study analyzes the visual perceptual difference of observers in the artworks created by human artists and artificial intelligence(AI) through eye-tracking. More specifically, the study analyzes the degree of visual attention through a fixation experiment on non-linguistic sources such as the formation and expression of artworks. As a result of this study, the subjects had guessed that one out of four artworks were created by AI (in actuality, 61.1% of the artworks were created by The Next Rembrandt). This demonstrates that most of the subjects hardly recognized the difference between the artwork of human artists and AI. From the comparative analysis of visual perceptual differences found through eye-tracking, more visual attention was found to be demanded for catching details of more stimulating visuals compared to less stimulating visuals. In the gender difference analysis, both of the female and male subjects were likely to stare more intently at the flowers of still-life paintings (Deep Dream & Vincent Van Gogh) while the eyes of a portrait painting (Rembrandt & The Next Rembrandt); this demonstrates no significant differences in gender. Various opinions on AI and art creation from different perspectives arose, therefore, this research is meaningful in a way that it suggests an objective examination through experiments with an artistic perspective.

• Korean Journal of Radiology
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• v.23 no.4
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• pp.479-487
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• 2022

Objective: To prospectively evaluate the efficacy of lauromacrogol injection for ablation (LIA) of benign predominantly cystic thyroid nodules and its related factors. Materials and Methods: A total of 142 benign predominantly cystic thyroid nodules (median volume, 12.5 mL; range, 0.4-156 mL) in 137 patients (male:female sex ratio, 36:101; mean age ± standard deviation [SD], 49 ± 13 years) were treated with LIA after being confirmed as benign via cytology. The volume reduction rate (VRR) of the nodules and cosmetic score were evaluated during follow-up at 1, 3, and 6 months after treatment and every 6 months thereafter. A VRR of ≥ 50% at the 12-month follow-up was considered to indicate effective treatment. The associations between the clinical factors and nodular ultrasound features, including the initial nodule volume, proportion of solid components, vascularity grade and ineffective treatment (VRR of < 50% at the 12-month follow-up), and regrowth were analyzed. Results: All patients completed follow-up for at least 12 months. The average ± SD follow-up period was 32 ± 11 months (range, 12-54 months). The effective treatment rate was 73.2% (104/142), while the regrowth rate was 12.0% (17/142) at the last follow-up. Grade 2-3 intranodular vascularity in the solid components of the nodules was the only independent factor associated with ineffective treatment, with an odds ratio (reference category, grade 0-1) of 3.054 (95% confidence interval, 1.148-8.127) (p = 0.025). Conclusion: LIA is an effective treatment for predominantly cystic thyroid nodules. Grade 2-3 intranodular vascularity in the solid components of nodules is the only independent risk factor for ineffective LIA.

• The Research Journal of the Costume Culture
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• v.32 no.2
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• pp.287-298
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• 2024

Clothing is intimately intertwined with daily lives as every individual relies on it. The pervasive issue of plagiarism in the fashion industry has led to an increased demand to protect intellectual property rights. Currently, studies on the protection of fashion design intellectual property rights in China remain in the exploratory stage and warrant further investigation. This paper addresses the issue in two parts. The first part contains an analysis of the theoretical foundation for the protection of fashion design copyrights. It is further divided into three subsections. The first subsection primarily examines the concept of copyrights and laws. The second subsection focuses on the concept of fashion design copyrights and laws. The third subsection analyzes copyright laws concerning fashion designs in China. The second section offers an analysis of infringement cases involving fashion designs published during the Baiyi Cup Intellectual Property Case Summary Writing Competition held in China in 2023. It outlines the shortcomings of the current Chinese copyright laws regarding the protection of fashion designs, and proposes measures for improvement. This study argues that the institutional framework for intellectual property rights in the Chinese fashion industry should align with practical considerations and explores suitable legal regulations and how they relate to specific circumstances in China. Besides refining the legal framework, fashion designers and enterprises must take measures to entablish the intellectual property rights of their clothing brands.

• Journal of the Korean Society of Physical Medicine
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• v.19 no.2
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• pp.1-16
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• 2024

PURPOSE: This study examined the effects of four weeks of gaze stabilization exercises and balance training on the static and dynamic balance functions. METHODS: The study was an assessor-blinded randomized controlled trial conducted at Daegu University in South Korea. Thirty subjects who fulfilled the inclusion criteria were selected and divided randomly into three groups containing ten each. The first group received balance exercises with gaze stabilizing exercises (BGG). The second group received a balance exercise (BEG), and the third group received gaze-stabilizing exercise (GEG). Each group exercised for 40 minutes, three times a week for four weeks. The subjects were asked to complete the following static balance test: 1) one-leg standing test, 2) sharpened Romberg test, dynamic balance test, 3) Y-balance test, and 4) single-leg stand-squat-stand test. The static and dynamic balance were measured before and after four weeks to determine the effect of exercise on balance. RESULTS: The static (OLS and SRT) and dynamic (YBT and SST) balance tests showed significant differences in the surface and length of the three groups (p < .05), and the y-balance score effect size, 11.477 (p < .05), was improved significantly. On the other hand, the change in BGG value was larger than those of BEG and GEG, and the improvements in balance control were the most significant. CONCLUSION: After four weeks of exercise, BGG showed the best improvement in static and dynamic balance, suggesting that this specific type of gaze stabilization exercise with balance exercise may benefit healthy young adults.