• Title/Summary/Keyword: multi-RAT

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Energy-Efficient Resource Allocation for Heterogeneous Cognitive Radio Network based on Two-Tier Crossover Genetic Algorithm

  • Jiao, Yan;Joe, Inwhee
    • Journal of Communications and Networks
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    • v.18 no.1
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    • pp.112-122
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    • 2016
  • Cognitive radio (CR) is considered an attractive technology to deal with the spectrum scarcity problem. Multi-radio access technology (multi-RAT) can improve network capacity because data are transmitted by multiple RANs (radio access networks) concurrently. Thus, multi-RAT embedded in a cognitive radio network (CRN) is a promising paradigm for developing spectrum efficiency and network capacity in future wireless networks. In this study, we consider a new CRN model in which the primary user networks consist of heterogeneous primary users (PUs). Specifically, we focus on the energy-efficient resource allocation (EERA) problem for CR users with a special location coverage overlapping region in which heterogeneous PUs operate simultaneously via multi-RAT. We propose a two-tier crossover genetic algorithm-based search scheme to obtain an optimal solution in terms of the power and bandwidth. In addition, we introduce a radio environment map to manage the resource allocation and network synchronization. The simulation results show the proposed algorithm is stable and has faster convergence. Our proposal can significantly increase the energy efficiency.

A Study of aticarcinogenic effects of dimethyl disulfide and diallyl disulfide in a rat multi-organ carcinogenesis model (다장기 발암모델을 이용한 dimethyl disulfide와 diallyl disulfide의 항발암효과)

  • Kang, Boo-Hyon;Son, Hwa-Young;Ha, Chang-Su;Rho, Jung-Koo
    • Korean Journal of Veterinary Pathology
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    • v.1 no.1
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    • pp.13-25
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    • 1997
  • The anticarcinogenic effects of dimethyl disulfide(DMDS, methyl disulfide)and diallyl disulfide(DADA, allyl disulfide) were studied in a 28 weeks rat multi-organ carcinogenesis model. neoplastic and preneoplastic lesions were observed in the liver kidney thyroid gland esophagus duodenum colon, rectum and adrenal gland. Tesults showed that neoplastic lesions in the kidney liver and thyroid gland were inhibited by DADS but those in the liver and colon were enhanced by DMDS when compared to positive control group. incidence of neoplastic lesions in the other organs were not changed by DMDS or DADS exposure. While GST-p positive foci in the liver were increased by DMDS, DADS had no effect. There was no significant histopathological lesion in DMDS or DADS treated group without pretreatment with carcinogens.

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A Study of Anticarcinogenic Effects of Allyl methyl Trisulfide and Methyl Propyl Disulfide on F344 Rats in a Rat Multi-organ Carcinogenesis Model (F344랫트를 이용한 다장기 발암모델에 나타난 Allyl Methyl Trisulfide와 Methyl Propyl Disulfide의 항발암효과)

  • Son, Hwa-Young;Kang, Boo-Hyon;Ha, Chang-Su;Roh, Jung-Koo
    • Korean Journal of Veterinary Pathology
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    • v.1 no.2
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    • pp.107-118
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    • 1997
  • The anticarcinogenic effects of allyl methyl trisulfide(AMT) and methyl propyl disulfide(MPD) were studied in a 28 weeks rat multi-organ carcinogenesis model. Tumor incidence rate was decreased by AMT or MPD treatment comparing with the positive control. AMT treatment significantly decreased the incidence of neoplastic and preneoplastic lesions in the kidney thyroid gland urinary bladder alimentary tract lung and Zymbal's gland. MPD also inhibited incidence of noplastic and preneoplastic lesions in the liver kidney urinary bladder alimentary tract lung and Zymbal's gland but increased that in the thyroid gland. GST-p positive foci in the liver were slightly decreased by AMT or MPD. There was no significant histopathological lesions in AMT or MPD treated group without pretreatment of carcinogens.

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Chemopreventive Effects of Ginseng on Rat Carcinogenesis

  • Wanibuchi Hideki;Ichihara Toshio;Morimura Keiichirou;Fukushima Shoji
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.277-287
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    • 2002
  • The chemopreventive effects of ginseng on rat carcinogenesis models were investigated, In the present study, the inhibitory effects of white and red ginseng on tumor development were examined using medium-term liver, initiation and medium-term multi-organ carcinogenicity bioassay systems. No modifying potential of the ginsengs was evident in terms of the numbers or areas of glutathione S-transferase placental form (GST -P)-positive foci, which is a marker of preneoplastic lesion in rat livers. However, white ginseng, but not red ginseng was found to decrease the incidences of adenocarcinoma of the small intestine and colon in the medium-term multi-organ carcinogenesis model. These results indicate that white ginseng may have inhibitory effects on progression stage of rat intestinal carcinogenesis, but the influence is not strong. Ginseng is unlikely to have promoting or inhibitory effects in other organs under the present type of experimental conditions. Possible application on ginseng for chemoprevention of colon cancer in humans, can be concluded given the lack of obvious adverse effects.

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Ultrastructural Change of the Bile Duct Fibroblast at Infected Rat with Clonorchis sinensis (간흡충에 감염된 실험쥐 담관 섬유모세포의 미세구조적 변화)

  • Kim, Soo-Jin;Min, Byoung-Hoon
    • Applied Microscopy
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    • v.34 no.2
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    • pp.121-130
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    • 2004
  • In this study, ultrastructural change of the bile duct fibroblast at infected rat with Clonorchis sinensis, and the distribution of lectin receptors and actin protein in cultured bile duct infected with Clonorchis sinensis. It explored using colloidal gold label complex with lectin WGA purified from wheat germ (Triticum vulgaris) and anti actin antibody purified actin (43 kDa) isolated from chicken back muscle. The lectin WGA with protein A gold complex labeled sections of the cultured fibroblast revealed gold particles specifically distributed on the multi vesicular form Golgi complex and cell surface of the fibroblast. The actin antibody with protein A gold complex labeled sections of the cultured fibroblast revealed gold particles specifically distributed on the cytoplasm of the fibroblast. Labeling of cultured fibroblast in rat bile duct infected with Clonorchis sinensis was then quantified and compared to that of cultured Fibroblast in Rat Bile duct. These results indicate that lectin WGA receptors are located in the multi vesicular form Golgi complex in the cytoplasm to the cytoplasmic process of the Rat bile duct fibroblast infected with Clonorchis sinensis. Therefore, the GlcNAc and NeuNac regions on the cell surface and cytoplasmic process appear to be functionally associated with cell-recognition and protection from other cell of the tissue, and linked with secretion and exocytosis of the fibroblst cytoplasm. GlcNAc and NeuNAc product in the multi vesicular form Golgi complex then it is transported to cell surface. Actin protein is many appears that infected fibroblast rather than normal fibroblast. The fibroblast of infected with Clonorchis sinensis are against of the physical and chemical stimulation. Then development of cytoplasmic process is relative some stimulation.

Enhancing Effects of Indole-3-carbinol on Hepatocarcinogenesis and Thyroid Tumorigenesis in a Rat Multi-Organ Carcinogenesis Model

  • Kim, Dae-Joong;Han, Beom-Seok;Ahn, Byeong-Woo;Kim, Chang-Ok;Choi, Kwang-Sik;Lee, Joon-Sup
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.339-339
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    • 1994
  • It has been reported that Indole-3-carbinol (I3C), a naturally occurring compound In cruclferous vegetables, exerts anticarcinogenic activity In several organs In rodents. The modifying effects of I3C were therefore assessed uging a rat multi-organ carcinogenesis model. A total of 100 male Sprague-Dawley rats were divided Into 3 groups. Animals of groups 1 and 2 were sequentially treated with diethylnitrosamine (DEN; 100 mg/kg b.w., i.p.), N-methylnitrosourea (NNU; 20 mg/kg b.w., 4 times for 2 weeks, i.p), and dihydroxy-di-N-propylnitrosauine (DHPN; 0.1% In d.w. for 2 weeks) for 4 weeks (DMD treatment). Animals of groups 1 and 3 were given the diet of 0.25% I3C for 20 weeks after DMD initiation and then were given basal diet for 28 weeks. All animals were sacrificed at week 24 and 52, respectively. I3C has been clearly demonstrated promoting effects on the development of glutathione S-transferase placental form (GST-P) positive hepatic foci at 24 weeks of the experiment. And I3C also exerted promoting potential In the hepatocellular adenoma (4/14; 29%) and the adenoma (7/14; 50%) of the thyroid gland at 52 weeks of the experiment. Therefore, I3C may promote hepatocarcinogenesis and thyroid tumorigenesis in the rat multi-organ carcinogenesis model.

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In Vivo Evaluation of Multi Lamellar Vesicle Liposome’s Percutaneous Absorption and Stability

  • Joung, Min-Seok;Park, Jong-Oan;Seo, Bong-Seok;Ryu, Chang-Duck
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.27 no.1
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    • pp.29-42
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    • 2001
  • We had prepared MLV liposome with Hibiscus Esculentus Ext.(HEE) which have fluorescent light in order to evaluate its percutaneous absorption about hairless rat skin. Then we investigated particle size of MLV using confocal laser scanning microscope(CLSM) and transmission electron microscope(TEM), respectively. Stability of MLV liposome and penetration of MLV liposome to hairless rat skin was measured by CLSM. As a result of experiments, MLV was globular shape and the rage of particle size was 0.3-0.5$\mu\textrm{m}$ mostly. Cream-type MLV had high stability comparatively. When we treated with MLV to rat skin, skin penetration was enhanced, especially, the optimum concentration of MLV on penetration to rat skin was 10%. Optimum penetration time was 6hr-12hr. And MLV-type HEE was more effective on percutaneous absorption than HEE-cream or liposome-type HEE.

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Modulation in Action Potentials of Rat Hippocampal Neurons Measured on Multi-Channel Electrodes During Ultrasound Stimulation (다채널 전극을 이용한 초음파 자극 시 쥐 해마 신경 세포의 활동 전위 검출)

  • Han, H.S.;Jeon, H.J.;Hwang, S.Y.;Lee, Y.N.;Byun, K.M.;Jun, S.B.;Kim, T.S.
    • Journal of Biomedical Engineering Research
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    • v.34 no.4
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    • pp.177-181
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    • 2013
  • It is known that ultrasound affects action potentials in neurons, but the underlying principles of ultrasonic neural stimulation are not clearly elucidated yet. In this study, we measured the action potentials of rat hippocampal neurons cultured on multi-electrode arrays during ultrasound stimulation. From most of electrodes, it was observed that the ultrasound stimulation increased the frequencies of action potentials (i.e., spikes) during ultrasound stimulation.

A Receiver-Aided Seamless And Smooth Inter-RAT Handover At Layer-2

  • Liu, Bin;Song, Rongfang;Hu, Haifeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.4015-4033
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    • 2015
  • The future mobile networks consist of hyper-dense heterogeneous and small cell networks of same or different radio access technologies (RAT). Integrating mobile networks of different RATs to provide seamless and smooth mobility service will be the target of future mobile converged network. Generally, handover from high-speed networks to low-speed networks faces many challenges from application perspective, such as abrupt bandwidth variation, packet loss, round trip time variation, connection disruption, and transmission blackout. Existing inter-RAT handover solutions cannot solve all the problems at the same time. Based on the high-layer convergence sublayer design, a new receiver-aided soft inter-RAT handover is proposed. This soft handover scheme takes advantage of multihoming ability of multi-mode mobile station (MS) to smooth handover procedure. In addition, handover procedure is seamless and applicable to frequent handover scenarios. The simulation results conducted in UMTS-WiMAX converged network scenario show that: in case of TCP traffics for handover from WiMAX to UMTS, not only handover latency and packet loss are eliminated completely, but also abrupt bandwidth/wireless RTT variation is smoothed. These delightful features make this soft handover scheme be a reasonable candidate of mobility management for future mobile converged networks.