• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.6
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• pp.660-669
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• 2010

In this paper, a multiple antenna system for next generation mobile applications is proposed. The proposed MIMO antenna consists of two parallel folded monopole antennas with the length of 100 mm and spacing of 6 mm and a decoupling network which locates at the top side of a mobile handset. In order to improve the isolation characteristic at the LTE band 13, a decoupling network was added between the two antenna elements placed close to each other. The decoupling network, consisting of two transmission lines, a shunt reactive component and common ground line, is simple and compact. To obtain the wide bandwidth characteristic, an wide folded patch structure generating the strong coupling between feeding and shorting lines through the slit is used at the bottom side of a mobile handset. Also, the performance of a multiple antenna system composed of three antenna elements is analyzed.

• Journal of Satellite, Information and Communications
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• v.8 no.1
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• pp.8-13
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• 2013

It is necessary to develop the next generation FTS which is suitable for our environment and effectively operates many launch vehicles. Standard tone, Secure tone, MHA, EFTS and DSSS are studied for the next generation FTS. FTS requires a high quality of performance and reliability because of their specific mission. And few FTSs are needed but the price is very expensive. Therefore we must investigate a part of the FTS whether the part can be reused for a part of the next FTS. In this paper, we use CCDF of the transmitted signal from FTS as the method to study a possibility of reusing HPA used in the present system. The simulation results show that PEP of Standard tone is 0.21dB and Secure tone and MHA has the same PEP. CPFSK's PEP is 1.81dB and PEP of DSSS using BPSK modulation is 2.6dB.

• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.205-210
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• 1999

Objectives: Major salivary gland tumor mainly develops in the parotid gland and pleomorphic adenoma is a large percentage. The aim of this study is to get clinicopathologic characteristics of overall major salivary gland tumors and suggestions regarding surgical management through collective review of 315 cases. Materials and Methods: This is a clinicopathologic review of 315 cases of major salivary gland tumor who were treated surgically at Department of Surgery, Head and Neck Clinic, Pusan Paik Hospital, Inje University during the period of 18 years from 1980 to 1997. Analysis was performed regarding the incidence, classification, surgery and its complications, and survival rate of salivary gland cancer. Results : 1) Parotid gland was the most prevalent site of salivary gland tumor(78%) and submandibular gland(21%) was next in order. Benign tumors were 257cases(81%) and malignant tumors were 58 cases(19%). 2) Male to female sex ratio was 1:1.2, the most prevalent age group was 3rd decade and the second group was 4th decade. 3) Histopathologically, the most common benign salivary gland tumor was pleomorphic adenoma. Warthin's tumor was next common. Among the malignant tumors, mucoepidermoid carcinoma was most common, and the next were adenoid cystic carcinoma and acinic cell carcinoma. 4) In pleomorphic adenoma, superficial parotidectomy was performed in 129 cases, and extracapsular tumorectomy was performed in 3 cases. In non-pleomorphic benign tumor, tumorectomy was performed in 21 cases. In 40 cases of deep lobe tumor, total parotidectomy was performed in only 2 cases and deep parotidectomy was performed in 38 cases. 5) Surgical complications were facial nerve injury 19 cases, Frey syndrome 13 cases, and salivary fistula 3 cases. 6) Overall 5-year survival rate of salivary gland cancer was 63%. Conclusion: Postoperative recurrence rate is low in benign tumor, but high in cancer of salivary gland tumor. Surgical procedure should not be aggressive in benign tumor, especially in parotid tumor, but should be aggressive in malignant salivary gland tumors.

• ETRI Journal
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• v.28 no.5
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• pp.561-573
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• 2006

In this paper, we present a practical implementation of the MPEG-21 multimedia framework for broadcasting and communication convergent services. MPEG-21 standard technology was exploited to build a convergent service framework. Using this framework, a service model and several scenarios have been successfully designed and implemented. In addition, interoperability, which is the main objective of a multimedia framework, especially in a convergent environment consisting of heterogeneous networks and various types of devices, has been addressed in detail. The experimental results show that the implemented test bed provides a next-generation multimedia service; that is, universal multimedia access (UMA), meeting the requirements of a broadcasting and communication convergent environment.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.652-658
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• 1999

To reveal the inhibitory mechanism of NO-dependent vasorelaxation by quinone derivatives (OQ1 and OQ21), we have compared the generation of free radicals by oxidative stress and the formation of cellular adducts by arylation. First, we measured oxygen consumption by quinone derivatives as a marker of oxidative stress in order to investigate whether these quinone compounds could generate reactive oxygen species. Both OQ1 and OQ21 generated free radicals and OQ21 was more potent. These results suggested that free radicals be involved in the inhibition of vasorelaxation by quinones. Next, we measured the binding capacity of quinone derivatives with intracellular GSH and protein thiols (-SH) in order to investigate whether these quinones have arylation capacity. Compared to positive control groups (menadione), both OQ1 and OQ21 depleted intracellular GSH and protein thiols very slightly. These compounds have low toxicities in mammalian tissues. From these results, we concluded that the inhibition of vasorelaxation by quinone derivatives (OQ1, OQ21) may be cuased by generation of free radicals.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.11
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• pp.2801-2809
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• 1996

Scheduling problems in real-time systems are known to be NP-hard. the heuristic approaches aregenerally aplied to solve a certain class of systems. One of such cases is to allocate periodic tasks to multiprocessors while the moethod assures the requirement of the deadine constraints of real-time systems. The study on the allocation of periodic taks includes RMNF, RMFF, FFDUF and Next-Fit-M algorithms, which make a set of task grups first and then allocate to processors. This papre proposes the various algorithms which are based on the Next-Fit-M. To analyze the four proposed methods, simulation was carried on, in which the sample tasks are randomly generated with the various time intervals. The proposed algorithms reduce the number of processors compared with the conventional methods.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.3
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• pp.21-28
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• 2004

In the near future we can expect a change in charging the Internet service. The flat charging maybe replaced with a usage-based charging. In line with this movement, we propose a method of charging the assured-quality Internet services for the next generation network by introducing a UBC (usage-based charging) scheme over the conventional flat charging platform. First, we investigate the attribute of elastic traffic generated by assured services in IP network. Next, we propose a new method to relate the bandwidth usage with the pricing for the elastic traffic, which is based partially on the usage rate of the network bandwidth. Next, we propose a charging function for elastic traffic, which is applicable to any type of assured Internet services. Finally, we discuss the implication of the work via simple numerical experiments.

• Journal of Conservation Science
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• v.37 no.4
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• pp.357-361
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• 2021

In order to determine the changes in microbial community due to termites, soil microorganisms surrounding the termites were investigated. First, bacterial communities from soil with termites collected at Seonamsa temple, Suncheon city, Korea were compared by next-generation sequencing (NGS, Illumina Miseq). The bacterial composition of soil from Daeungjeon without termites and the soil from Josadang, Palsangjeon, and Samjeon with termites were compared. Next, the bacterial composition of these soils was also compared with that of humus soil cultured with termites. A total high-quality sequences of 71,942 and 72,429 reads were identified in Seonamsa temple's soil and humus soil, respectively. The dominant phyla in the collected Seonamsa temple's soil were Proteobacteria (27%), Firmicutes (24%) and Actinobacteria (21%), whereas those in the humus soil were Bacteriodetes (56%) and Proteobacteria (37%). Using a two-dimensional plot to explain the principal coordinate analysis of operational taxonomic unit compositions of the soil samples, it was confirmed that the samples were divided into soil with and without termites, and it was especially confirmed that the Proteobacteria phylum was increased in humus soil with termites than in humus soil without termites.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.1-6
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• 2009

Microglial cells constitute the first line of defense against infection and injury in the brain. This study was conducted to evaluate the protective mechanisms of Agrimonia pilosa (AP) on LPS-induced activation of BV-2 microglial cells. The effects of AP on gene expression profiles in activated BV-2 microglial cells were evaluated using microarray analysis. BV-2 microglial cells were cultured in a 100 mm dish ($1{\times}10^7/mL$) for 24 hr and then pretreated with 1 g/mL AP or left untreated for 30 min. Next, 1 g/mL LPS was added to the samples and the cells were reincubated at $37^{\circ}C$ for 30 min, 3 hr and 6 hr. The gene expression profiles of the BV-2 microglial cells varied depending on the AP. The microarray analysis revealed that MAPK signaling pathway-related genes were down-regulated and IL10 gene was up-regulated in AP-treated BV-2 microglial cells. AP can affect the inflammatory response and MAPK pathway in BV-2 microglial cells.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1410-1416
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• 2015

Wolbachia is an obligate symbiotic bacteria that is ubiquitous in arthropods, with 25-70% of insect species estimated to be infected. Wolbachia species can interact with their insect hosts in a mutualistic or parasitic manner. Sequence types (ST) of Wolbachia are determined by multilocus sequence typing (MLST) of housekeeping genes. However, there are some limitations to MLST with respect to the generation of clone libraries and the Sanger sequencing method when a host is infected with multiple STs of Wolbachia. To assess the feasibility of massive parallel sequencing, also known as next-generation sequencing, we used pyrosequencing for sequence typing of Wolbachia in butterflies. We collected three species of butterflies (Eurema hecabe, Eurema laeta, and Tongeia fischeri) common to Korea and screened them for Wolbachia STs. We found that T. fischeri was infected with a single ST of Wolbachia, ST41. In contrast, E. hecabe and E. laeta were each infected with two STs of Wolbachia, ST41 and ST40. Our results clearly demonstrate that pyrosequencing-based MLST has a higher sensitivity than cloning and Sanger sequencing methods for the detection of minor alleles. Considering the high prevalence of infection with multiple Wolbachia STs, next-generation sequencing with improved analysis would assist with scaling up approaches to Wolbachia MLST.