• Title/Summary/Keyword: signaling state

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Separated Control Signaling Protocol for WDM Optical Networks (파장 분할 다중화 방식을 사용하는 광 전송망을 위한 분리 제어 신호 방식)

  • 소원호;김영천
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.6
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    • pp.361-361
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    • 2000
  • In this paper, we propose a novel control signaling protocol that efficiently controls connection setup and increases the utilization of network resources. The proposed protocol, Separated Control Signaling Protocol(SCSP), separates bearer control from call control lot WDM optical networks. The main function of call control is to check the availability of network resources such as wavelengths and receivers at destination node. Bearer control is to reserve and assign wavelengths. The signaling architecture of this protocol consists of call controller and hearer controller The call controller handles call setup and release, activates the beater controller, and manages the status of call and bearer. The bearer controller reserves wavelengths, sets up bearer, tears down bearer. and notifies the status of beater to call controller. The state transition diagrams of each controller are designed. Using control messages and related primitives, the information flows for call setup and bearer setup, hearer teardown and call release, and reaction for setup failures are described to evaluate the performance. The simulation results show that the separated control signaling protocol is superior to conventional one in terms of call blocking probability and resource utilization.

Dimethyl Cardamonin Exhibits Anti-inflammatory Effects via Interfering with the PI3K-PDK1-PKCα Signaling Pathway

  • Yu, Wan-Guo;He, Hao;Yao, Jing-Yun;Zhu, Yi-Xiang;Lu, Yan-Hua
    • Biomolecules & Therapeutics
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    • v.23 no.6
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    • pp.549-556
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    • 2015
  • Consumption of herbal tea [flower buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry (Myrtaceae)] is associated with health beneficial effects against multiple diseases including diabetes, asthma, and inflammatory bowel disease. Emerging evidences have reported that High mobility group box 1 (HMGB1) is considered as a key "late" proinflammatory factor by its unique secretion pattern in aforementioned diseases. Dimethyl cardamonin (2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone, DMC) is a major ingredient of C. operculatus flower buds. In this study, the anti-inflammatory effects of DMC and its underlying molecular mechanisms were investigated on lipopolysaccharide (LPS)-induced macrophages. DMC notably suppressed the mRNA expressions of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, and HMGB1, and also markedly decreased their productions in a time- and dose-dependent manner. Intriguingly, DMC could notably reduce LPS-stimulated HMGB1 secretion and its nucleo-cytoplasmic translocation. Furthermore, DMC dose-dependently inhibited the activation of phosphatidylinositol 3-kinase (PI3K), phosphoinositide-dependent kinase 1 (PDK1), and protein kinase C alpha (PKC${\alpha}$). All these data demonstrated that DMC had anti-inflammatory effects through reducing both early (TNF-${\alpha}$, IL-$1{\beta}$, and IL-6) and late (HMGB1) cytokines expressions via interfering with the PI3K-PDK1-PKC${\alpha}$ signaling pathway.

Expression Characteristics of Proteins of the Insulin-like Growth Factor Axis in Non-small Cell Lung Cancer Patients with Preexisting Type 2 Diabetes Mellitus

  • Ding, Jing;Tang, Jie;Chen, Xin;Men, Hai-Tao;Luo, Wu-Xia;Du, Yang;Ge, Jun;Li, Cong;Chen, Ye;Cheng, Ke;Qiu, Meng;Liu, Ji-Yan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5675-5680
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    • 2013
  • Background: Preexisting type 2 diabetes mellitus (T2DM) affects the prognosis and mortality of patients with some cancers. Insulin like growth factor (IGF) and insulin receptor (IR) signaling axes play important roles in both cancer and diabetes development. We aimed to explore the expression characteristics of proteins in IGF/IR axis in non-small cell lung cancer (NSCLC) cases with preexisting T2DM. Methods: Fifty-five NSCLC patients with preexisting T2DM were retrospectively included and matched by 55 NSCLC without diabetes at a 1:1 ratio. The expression of proteins in IGF/IR axis was detected by immunohistochemical staining. Clinicopathological data were collected to analyze their relationship with the protein expression. Results: Both IGF 1 receptor (IGF-1R) and insulin receptor substrate 2 (IRS-2) showed higher expression in the NSCLC with T2DM group, compared with those without T2DM. The high expression of IGF-1R and IRS-2 were found to be negatively associated with lymph node metastases and T staging in the T2DM group, respectively, and IRS-2 expression was also found more in the subgroup whose T2DM duration was more than 4 years. No difference was detected in the expression of IRS-1, IGF-1, IGF-2, IGFBP3, IR and mTOR between groups with or without T2DM. Conclusion: Our study found higher expression of IGF-1R and IRS-2 proteins in NSCLC patients with preexisting T2DM, and that there was an association with early stage NSCLC, which suggested that IGF signaling may play an important early event in development of NSCLC associated with diabetes.

Barbigerone Inhibits Tumor Angiogenesis, Growth and Metastasis in Melanoma

  • Yang, Jian-Hong;Hu, Jia;Wan, Li;Chen, Li-Juan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.167-174
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    • 2014
  • Tumor angiogenesis, growth and metastasis are three closely related processes. We therefore investigated the effects of barbigerone on all three in the B16F10 tumor model established in both zebrafish and mouse models, and explored underlying molecular mechanisms. In vitro, barbigerone inhibited B16F10 cell proliferation, survival, migration and invasion and suppressed human umbilical vascular endothelial cell migration, invasion and tube formation in concentration-dependent manners. In the transgenic zebrafish model, treatment with $10{\mu}M$ barbigerone remarkably inhibited angiogenesis and tumor-associated angiogenesis by reducing blood vessel development more than 90%. In vivo, barbigerone significantly suppressed angiogenesis as measured by H and E staining of matrigel plugs and CD31 staining of B16F10 melanoma tumors in C57BL/6 mice. Furthermore, it exhibited highly potent activity at inhibiting tumor growth and metastasis to the lung of B16F10 melanoma cells injected into C57BL/6 mice. Western blotting revealed that barbigerone inhibited phosphorylation of AKT, FAK and MAPK family members, including ERK, JNK, and p38 MAPKs, in B16F10 cells mainly through the MEK3/6/p38 MAPK signaling pathway. These findings suggested for the first time that barbigerone could inhibit tumor-angiogenesis, tumor growth and lung metastasis via downregulation of the MEK3/6/p38 MAPK signaling pathway. The findings support further investigation of barbigerone as a potential anti-cancer drug.

Torque Ripple Reduction of Interior Permanent-Magnet Synchronous Motors Driven by Torque Predictive Control (토크예측제어를 이용한 매입형 영구자석 동기전동기의 토크리플저감기법)

  • Kim, Hyunseob;Han, Jungho;Song, Joong-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.2
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    • pp.102-109
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    • 2013
  • In this paper, a new torque predictive control method of interior permanent magnet synchronous motor is developed based on an extended rotor flux. Also, a duty ratio prediction method is proposed and allows the duty ratio of the active stator voltage vector to be continuously calculated. The proposed method makes it possible to relatively reduce the torque ripple under the steady state as well as to remain the good dynamic response in the transient state. With the duty ratio prediction method, the magnitude and time interval of the active stator voltage vector applied can be continuously controlled against the varying operation conditions. This paper shows a comparative study among the switching table direct torque control(DTC), the SVM-DTC, conventional torque predictive control, and the proposed torque predictive control. Simulation results show validity and effectiveness of this work.

ML Symbol Detection for MIMO Systems in the Presence of Channel Estimation Errors

  • Yoo, Namsik;Back, Jong-Hyen;Choi, Hyeon-Yeong;Lee, Kyungchun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.11
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    • pp.5305-5321
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    • 2016
  • In wireless communication, the multiple-input multiple-output (MIMO) system is a well-known approach to improve the reliability as well as the data rate. In MIMO systems, channel state information (CSI) is typically required at the receiver to detect transmitted signals; however, in practical systems, the CSI is imperfect and contains errors, which affect the overall system performance. In this paper, we propose a novel maximum likelihood (ML) scheme for MIMO systems that is robust to the CSI errors. We apply an optimization method to estimate an instantaneous covariance matrix of the CSI errors in order to improve the detection performance. Furthermore, we propose the employment of the list sphere decoding (LSD) scheme to reduce the computational complexity, which is capable of efficiently finding a reduced set of the candidate symbol vectors for the computation of the covariance matrix of the CSI errors. An iterative detection scheme is also proposed to further improve the detection performance.

Enhancement of Return Routability Mechanism for Optimized-NEMO Using Correspondent Firewall

  • Hasan, Samer Sami;Hassan, Rosilah
    • ETRI Journal
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    • v.35 no.1
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    • pp.41-50
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    • 2013
  • Network Mobility (NEMO) handles mobility of multiple nodes in an aggregate manner as a mobile network. The standard NEMO suffers from a number of limitations, such as inefficient routing and increased handoff latency. Most previous studies attempting to solve such problems have imposed an extra signaling load and/or modified the functionalities of the main entities. In this paper, we propose a more secure and lightweight route optimization (RO) mechanism based on exploiting the firewall in performing the RO services on behalf of the correspondent nodes (CNs). The proposed mechanism provides secure communications by making an authorized decision about the mobile router (MR) home of address, MR care of address, and the complete mobile network prefixes underneath the MR. In addition, it reduces the total signaling required for NEMO handoffs, especially when the number of mobile network nodes and/or CNs is increased. Moreover, our proposed mechanism can be easily deployed without modifying the mobility protocol stack of CNs. A thorough analytical model and network simulator (Ns-2) are used for evaluating the performance of the proposed mechanism compared with NEMO basic support protocol and state-of-the-art RO schemes. Numerical and simulation results demonstrate that our proposed mechanism outperforms other RO schemes in terms of handoff latency and total signaling load on wired and wireless links.

A Study on the Influence of Mutual Inductance between Wayside Transmitter and On-board Receiver upon Frequency Response in ATS Device (ATS 장치에서 지상자와 차상자 사이의 상호인덕턴스가 주파수 응답에 미치는 영향)

  • Kim, Min-Seok;Kim, Min-Kyu;Lee, Jong-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.3
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    • pp.384-393
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    • 2012
  • Railroad signaling systems perform controlling the distance and routes between trains. Signaling methods on the wayside are to control passively the train speed by using signal flags which are installed on the wayside. ATS(Automatic Train Stop) device is used as the signaling method on the wayside in Korea. The ATS device is assistance equipment of engineers. Signal information is transmitted by combining mutual inductance between the wayside transmitter and on-board receiver. The wayside transmitter performs changing oscillation frequency according to the signal information. The on-board receiver performs controlling the train by receiving the frequency. Currently, the oscillation frequency on the on-board receiver is 78[kHz] in case of normal state. When the on-board receiver is over the wayside transmitter, the oscillation frequency is changed by capacitors of the wayside transmitter according to signal flags. In case of changing the oscillation frequency, the waveform is modified in the wayside transmitter and on-board receiver. This phenomenon is that other signals or communication frequency are included. In this paper, electric model between the wayside transmitter and on-board receiver is suggested and frequency response in the wayside transmitter and on-board receiver including other signals is estimated by the coupling coefficient. Also, the value of coupling coefficient is proposed to exclude other signals and demonstrated by using Matlab and PSpice program.

Wireless Host Agent (WHA)-based IP Multicast Group Management Scheme (무선 호스트 에이전트 기반 IP 멀티캐스트 그룹 관리 기법)

  • Lee, Ji-Hoon;Suh, Jun-Ho;Kwon, Ted Tae-Kyoung;Choi, Yang-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.10B
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    • pp.1004-1012
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    • 2009
  • Although it is raising expectation of multimedia multicast services in various wireless networks, it requires an efficient IP multicast group membership management in wireless environment. However, the existing IGMPv3/MLDv2 protocols are too heavy; they are not suitable for wireless environment. Moreover they suffer from a number of problems, such as unreliable signaling, slow state transition, low spectral efficiency, bulk report, and interrupting dormant receivers. In this paper, we propose a wireless host agent (WHA)-based IP multicast group management scheme that requires a reduced number of signaling, which also solves such problems effectively. We develop an analytic model to quantify costs of bandwidth usage and signaling overhead, and perform comparison and analysis of the proposed scheme.

An Evaluation of Listening Studies concerning Discourse Signaling Cues: Focus on Research Designs

  • Jung, Euen-Hyuk
    • English Language & Literature Teaching
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    • v.15 no.4
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    • pp.55-74
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    • 2009
  • Although a considerable amount of research on discourse signaling cues has been conducted in reading, little attention has been paid to such cues in the area of listening. Moreover, despite the solid evidence showing that cues have beneficial effects for reading comprehension, L2 listening research has produced mixed findings about the role of cues. Such discrepancies among these findings might be due in part to inadequate research methodologies as well as the idiosyncratic features of their experimental designs. However, no study, to date, has thoroughly examined the research designs of listening comprehension studies on cues. Consequently, this study critically evaluates the present state of research designs and reporting practices of studies investigating the role of cues in listening comprehension. The present study aims to provide insights into areas that require empirical attention and systematic investigation. It also seeks to encourage improved and refined research practices for future studies. This paper is organized as follows: It will first critically review the empirical findings regarding cues in the area of L1 listening comprehension. Second, it will present a critical evaluation of L2 listening studies on cues. Finally, it will address the major research design issues of currently available listening studies and provide suggestions for improvement in future research.

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