• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.202-208
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• 2001

Aluminum dross should be recycled in consideration of characteristics of the dross and its reutilization after processing. In this study, aluminum dross generated in the domestic secondary aluminum industry was processed to use it as raw material for producing aluminum hydroxide. Sample dross was classified according to its size. The dross smaller than 1mm was leached with sodium hydroxide solution to extract the remaining aluminum from the dross into the solution, and then aluminum hydroxide precipitate was recovered from the leach liquor. Purity of the obtained aluminum hydroxide was above 98 percent, and particle size of the sample was in range of 3-39${\mu}{\textrm}{m}$. From the result, it was suggested that this process could be applicable to recycling of aluminum dross.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.202-206
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• 2009

In many countries including China and U.S., researchers are developing methods to use sweetpotato as raw material for biofuel. We consider the sweetpotato is not only a source of green fuel, it eventually will provide various material including paper, adhesives, biodegradable plastics, and secondary metabolites. Sweetpotato is one of the high efficiency crop because it yields more calories per unit area than either maize or potato, and it requires the shortest growing cycle of the root crops grown in the tropics. Sweetpotato is the most useful crop for the coming starchbased industry era. Sweetpotato genetic resources are collected, characterized, evaluated, and maintained by U.S., China, Japan, and the International Potato Center. New varieties of sweetpotato using the proper genetic resources and molecular breeding will be developed to cope with the global food and energy in 21st century.

• Journal of Species Research
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• v.3 no.1
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• pp.39-52
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• 2014

The Apiaceae genus Daucus consists of approximately 25 species (including carrots) which are characterized by the presence of bracts in pedunculate umbels, dorsally compressed mericarps, hairs on primary ridges, and uniseriately arranged spines on the secondary ridges of the fruit. Taxonomically, Daucus has been considered to be one of the most problematic genera in the Apiaceae due to the highly variable fruit morphology. Despite taxonomic controversy and economic importance of the genus, no rigorously constructed estimate of phylogenetic relationships exists. To examine generic limit and relationships among species of Daucus and its putatively related taxa, phylogenetic analyses of characters derived from nuclear ribosomal DNA ITS sequences were conducted. Two major clades emerged within Daucus, but neither of them have been previously recognized using morphological characters. The phylogeny also provides taxonomic status of recently reported new species of Daucus, D. arcanus and D. conchitae.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.316-325
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• 2018

Aluminum based metal-organic framework using a di-carboxylate linker succinic acid (Al-SA MOF), are synthesized in water with minimal generation of secondary pollutants. The physicochemical properties of Al-SA MOF were examined, followed by its utility for the adsorption of Acid Black 1 (AB1) in aqueous media. Influences of key parameters such as pH, contact time, initial AB1 concentration,temperature, and selectivity on the adsorption process were assessed. A series of adsorption mechanisms are proposed, which involve electrostatic, hydrogen bonding, and hydrophobic interactions. These findings suggest that Al-SA MOF is a potent candidate in removing complex azo dyes molecules from aqueous media.

• Journal of Species Research
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• v.12 no.1
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• pp.38-47
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• 2023

Seven new species of genus Dysidea (Demospongiae: Dictyoceratida: Dysideidae) are described from Jejudo Island and Geomundo Island, Korea. These new species are compared with other reported species in fibre structure and arrangement, and cored detritus. Dysidea reticulum n. sp. is similar to D. glavea in skeletal structure but differ in sponge shape. Dysidea simplex n. sp. is close to D. glavea with loosely arranged skeletal structure but fibres in this new species are not cored with large sands. Dysidea pyeongdaensis n. sp. is characterized by tube-like surface oscules open toward the sandy bottom. Dysidea capillus n. sp. is similar to D. dokdoensis in skeletal structure, but differs in long surface conules. Dysidea mukriensis n. sp. is close to D. corallina in distinct dense surface conules, but differs in sponge shape and skeletal structure. Dysidea membrana n. sp. is similar to D. sabulum in primary fibres cored with numerous large sands, but differs in sponge surface conules and secondary fibres. Dysidea chujaensis n. sp. is unique in the sponge shape and skeletal structure.

• Plant Biotechnology Reports
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• v.4 no.4
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• pp.253-260
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• 2010

Plant secondary metabolites have always been a focus of study due to their important roles in human medicine and nutrition. We transferred the isoflavone synthase (IFS) gene into soybean [Glycine max (L.) Merr.] using the Agrobacterium-mediated transformation method in an attempt to produce transformed soybean plants which produced increased levels of the secondary metabolite, isoflavone. Although the trial to produce transgenic plant failed due to unestablished hygromycin selection, transformed callus cell lines were obtained. The induction rate and degree of callus were similar among the three cultivars tested, but light illumination positively influenced the frequency of callus formation, resulting in a callus induction rate of 74% for Kwangan, 67% for Sojin, and 73% for Duyou. Following seven to eight subcultures on selection media, the isoflavone content of the transformed callus lines were analyzed by high-performance liquid chromatography. The total amount of isoflavone in the transformed callus cell lines was three- to sixfold higher than that in control callus or seeds. Given the many positive effects of isoflavone on human health, it may be possible to adapt our transformed callus lines for industrialization through an alternative cell culture system to produce high concentrations of isoflavones.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.98-105
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• 1998

We measured seedling growth, foliar nutrient and extract concentrations of 3-year-old Ginkgo biloba seedlings growing in a nursery following a single fertilization with nitrogen (N), phosphorus (P) and nitrogen plus phosphorus (N+P) fertilizers. Fertilization did not change foliage, stem and root biomass of the seedlings except for the high N+P treatment, Foliar N and P concentrations following fertilization varied according to the amount of fertilizers. In general, foliar N and P concentrations increased with fertilization, but fertilization with 400kg N/ha and 100kg P/ha decreased foliar N and P concentrations, respectively. Seedling growth and foliar nutrient concentrations showed that N and P were the growth-limiting nutrients in our study site. It was found that fertilization reduced the concentrations of secondary metabolites (Ginkgo flavon glycosides and terpene lactones) in foliages. It seemed there was a relationship between foliage biomass production and secondary chemicals in G. biloba seedlings.

• KIISE Transactions on Computing Practices
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• v.20 no.12
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• pp.688-693
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• 2014

With the advent of ubiquitous environments, the smart phone has come into wide use and the demand for various content increases. Thus, in order to efficiently utilize limited resources cognitive radio technology is regarded as a possible solution. Besides spectrum sensing or access schemes, the provision of VoIP traffic service for secondary users with limited spectrum resources is a very important issue. In this paper, a resource allocation and control system for VoIP QoS provision in cognitive radio networks is proposed. Firstly, as the system model, the time structure of the network is addressed and, according to the structure, a bandwidth broker is proposed. In addition, based on available bandwidth estimated by the bandwidth broker, a connection admission control for secondary users is developed. It is demonstrated that the provision of VoIP QoS is greatly affected by channel utilization, the number of channels, and the length of timeslot.

• Journal of Advanced Navigation Technology
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• v.20 no.5
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• pp.440-445
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• 2016

There is a scheme where secondary users (SU) use predicted spectrum holes for primary users (PU) not to utilize for efficient utilization of the limited spectrum resources in cognitive radio networks. In this paper, we propose an adaptive call admission control framework that minimizes spectrum hopping call dropped probability (SHDP) for satisfying SU quality of service (QoS). The scheme is based on a call admission control (CAC), bandwidth prediction and adaptive bandwidth assignment. The prediction model predicts not only the number of spectrum holes, but requested bandwidth of SU spectrum hopping call, and then the CAC minimizes SHDP via an adaptive bandwidth assignment in resources not being enough for reservation. We bring Wiener prediction model to predict the resources. Simulations are conducted to compare the performance of proposed scheme with an existing, and show its ability of minimizing the SHDP.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.2
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• pp.85-102
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• 2021

Phytosociological characteristics on Quercus acutissima forests distribution in Daechong-dam basin survey has been carried out using Z.-M. School's methodology and numerical-classification analyses. A total of 43 phytosociological relevés were sampled. Syntaxa were described as Oplismenus undulatifolius-Quercus acutissima community(typicum subcommunity, Phryma leptostachya var. asiatica subcommunity, Ulmus davidiana var. japonica subcommunity), Quercus acutissima community and Quercus variabilis-Quercus acutissima community (typicum subcommunity, Castanea crenata subcommunity). The above three plant communities were classified with species composition reflecting local environmental characteristics of mountain topographies, inclination degrees, and rock exposure rates. Conclusively, those communities were recognized as secondary vegetation affected by high intensity and frequency of human impacts as they inhabited in southward hill lands and low lying grounds in mountains adjacent to human settlements and arable lands. Quercus acutissima community was classified as rural type syntax based on their inlandward distribution and species composition differences from urban forests. Afforest process and natural succession were discussed in relation with habitat environmental elements of Quercus acutissima forest in the survey area.