• Journal of IKEEE
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• v.27 no.4
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• pp.425-429
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• 2023

In this paper, the scheme to activate the active elements of reconfigurable intelligent surface(RIS) is proposed. Recently, RIS has been studied as a technology that improves communication coverage and spectral efficiency in wireless communication system. RIS can adjust the phase and amplitude of the received signal, and can ensure better communication performance in areas with many obstacles, such as urban areas. However, due to RIS, the signal undergoes fading twice and performance decrease in communication. Recently, RIS using active reflection elements has been studied to solve these problems. However, if the entire RIS is used as an active reflection element, energy consumption increases. Accordingly, in this paper, we propose a system that utilizes some of the RIS reflective elements as active reflective elements and a scheme for selecting active reflective elements to be activated.

• STI Policy Review
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• v.5 no.1
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• pp.112-130
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• 2014

Many actors are involved in the development of regional innovation systems (RIS) such as universities, private firms, research institutions, governments, and public agencies. In a country like Korea, where the central government takes more than 95% of the total government R&D budget, the role of regional authorities in science, technology, and innovation are fairly limited, although in recent years some regional governments have tried to promote innovation activity in their localities. This paper looks into the Gyeonggi Institute of Science and Technology Promotion (GSTEP) in Gyeonggi Province and examines its emerging role and achievements in innovation policymaking. It was found out that GSTEP engages in knowledge brokering with the purpose of helping firms participate in regional technological innovation processes. The knowledge brokering roles of this regional authority are described along with their implications for regional innovation policy. This study aims for a deeper understanding of the nature of the regional authority's role in a RIS through the case study of regional actors transitioning from being subordinators to becoming active participants with greater participation on policymaking and implementation.

• Journal of Life Science
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• v.22 no.6
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• pp.852-856
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• 2012

Dichloromethane, ethanol, and boiling water extracts of the green seaweed Codium fragile, used as an herbal medicine and known as an invasive species over the world, were examined for anti-inflammatory, antipyretic, and analgesic activities in mice. The dichloromethane and ethanol extracts inhibited inflammatory symptoms of mouse ear edema and erythema by 74% or higher. The extracts also demonstrated inhibition of pyrexia, similar to that of acetyl salicylic acid. Eicosapentaenoic acid was isolated from the seaweed as the main active anti-inflammatory compound. These findings are consistent with various claims that the seaweed can be used as remedies for inflammation-related symptoms.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.3
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• pp.490-508
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• 2013

One of the most important scalability issues facing the current Internet is the rapidly increasing rate of BGP updates (BGP churn), to which route flap and path exploration are the two major contributors. Current countermeasures would either cause severe reachability loss or delay BGP convergence, and are becoming less attractive for the rising concern about routing convergence as the prevalence of Internet-based real time applications. Based on the observation that highly active prefixes usually repeatedly explore very few as-paths during path exploration, we propose a router-level mechanism, Path Exploration Aggregation (PEA), to scale BGP without either causing prefix unreachable or slowing routing convergence. PEA performs aggregation on the transient paths explored by a highly active prefix, and propagates the aggregated path instead to reduce the updates caused by as-path changes. Moreover, in order to avoid the use of unstable routes, PEA purposely prolongs the aggregated path via as-path prepending to make it less preferred in the perspective of downstream routers. With the BGP traces obtained from RouteViews and RIPE-RIS projects, PEA can reduce BGP updates by up to 63.1%, shorten path exploration duration by up to 53.3%, and accelerate the convergence 7.39 seconds on average per routing event.

• Preventive Nutrition and Food Science
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• v.20 no.2
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• pp.119-125
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• 2015

The biologically active compounds raphasatin and sulforaphene are formed during the hydrolysis of radishes by an endogenous myrosinase. Raphasatin is very unstable, and it is generated and simultaneously degraded to less active compounds during hydrolysis in aqueous media. This study determined the hydrolysis conditions to maximize the formation of raphasatin and sulforaphene by an endogenous myrosinase and minimize their degradation during the hydrolysis of radish roots. The reaction parameters, such as the reaction medium, reaction time, type of mixing, and reaction temperature were optimized. A stability test for raphasatin and sulforaphene was also performed during storage of the hydrolyzed products at $25^{\circ}C$ for 10 days. The formation and breakdown of raphasatin and sulforaphene in radish roots by endogenous enzymolysis was strongly influenced by the reaction medium, reaction time, and type of mixing. The production and stabilization of raphasatin in radishes was efficient in water and dichloromethane with shaking for 15 min at $25^{\circ}C$. For sulforaphene, the favorable condition was water as the reaction medium without shaking for 10 min at $25^{\circ}C$. The maximum yields of raphasatin and sulforaphene were achieved in a concurrent hydrolysis reaction without shaking in water for 10 min and then with shaking in dichloromethane for 15 min at $25^{\circ}C$. Under these conditions, the yields of raphasatin and sulforaphene were maximized at 12.89 and $1.93{\mu}mol/g$ of dry radish, respectively. The stabilities of raphasatin and sulforaphene in the hydrolyzed products were 56.4% and 86.5% after 10 days of storage in water and dichloromethane at $25^{\circ}C$.