• Title/Summary/Keyword: Common channel

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Mechanism of $Ca^{2+}$ -activated $Cl^-$ Channel Activation by Ginsenosides in Xenopus Oocytes

  • Park, Seok;Jung, Se-Yeon;Park, Seong-Hwan;Ko, Sung-Ryong;Hyewon Rhim;Park, Chul-Seung;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.24 no.4
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    • pp.168-175
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    • 2000
  • Relatively little is known about the signaling mechanism of ginseng saponins (ginsenosides), active ingredients of ginseng, in non-neuronal cells. Here, we describe that ginsenosides utilize a common pathway of receptor-mediated signaling pathway in Xenopus oocytes: increase in intracellular $Ca^{2+}$ concentration via phospholipase C (PLC) and $Ca^{2+}$ mobilization. Ginsenosides induced a marked and robust artivation of $Ca^{2+}$-activated Cl- channels in Xenopus oocytes. The effect of ginsenosides was completely reversible, in a dose-dependent manner with EC$_{50}$ of 4.4 $\mu\textrm{g}$/mi, and specifically blocked by niflumic acid, an inhibitor of $Ca^{2+}$-activated Cl- channel. Intracellular injection of BAPIA abolished the effect of ginsenosides. Intracellular injection of GTP${\gamma}$S also abolished the effect of ginsenosides. The effect of gin senosides on $Ca^{2+}$-activated Cl- currents was greatly reduced by the intracellular injection of heparin, an IP$_3$ receptorantagonist or the pretreatment of PLC inhibitor. These results indicate that ginsenosides activate endogenous $Ca^{2+}$-activated Cl- channels via the activation of PLC and the release of $Ca^{2+}$ from the IP$_3$-sensitive intracellular store following the initial interaction with membrane component(s) from extracellular side. This signaling pathway of ginsenosides may be one of the action mechanisms for the pharmacological effects of ginseng.ts of ginseng.

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A Research on Performance Improvement of Wireless LAN System (무선 LAN 시스템 성능개선에 관한 연구)

  • Cho, Juphil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.5
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    • pp.1028-1033
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    • 2014
  • We investigate the OFDM-based wireless LAN systems operating in the 60 GHz frequency band as part of the fourth-generation (4G) systems. The 60 GHz band is of much interest since this is the band in which a massive amount of spectral space has been allocated worldwide for dense wireless local communications. This paper gives an overview of 60 GHz band channel characteristics and an effect on phase noise. The performance of OFDM system is severely degraded by the local oscillator phase noise, which causes both common phase error and inter-carrier interference. In this paper, we apply phase noise suppression (PNS) algorithm that is easy for implementation to OFDM based 60 GHz wireless LAN system and analyze the SER performance. In case of using the PNS algorithm, SER performance is improved about 6 dB, 7.5 dB, respectively in 16, 64-QAM.

Priority Collision Resolution Algorithm on HFC Networks (우선 순위를 고려한 HFC 망의 충돌 해소 알고리즘)

  • 김변곤;박준성;정경택;전병실
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.7B
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    • pp.1252-1260
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    • 1999
  • The HFC network has a architecture of a star topology in fiber optic trunks, and tree and branch topology is used in the part of coaxial cable. It is well known that the HFC upstream channel is noisy. Ingress, common mode distortion and impulse noise exist in the upstream channel. In order to provide Quality of Service(QoS) to users with real-time data such as voice, video and interactive services, the evolving IEEE 802.14 standard for HFC networks must include an effective priority scheme. The scheme separates and resolves collisions between stations in a priority order. It is important to simulate protocols under a practical environment. The proposed algorithm in this paper is simulated with the assumption that the collision detector made certain mistake due to noises. Simulation results show that the proposed algorithm is more efficient than existing tree-based algorithm under practical environment.

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A Study on Nucleus Extraction of Uterine Cervical Pap-Smears (자궁 경부진 핵 추출에 관한 연구)

  • Kim, Kwang-Baek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.8
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    • pp.1699-1704
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    • 2009
  • If detected early enough, cervical cantor may have a good survival rate due to its preneoplastic state. However, the process is so time consuming that a medical expert can handle only a small amount of such examinations. In this paper, we propose a new nucleus extraction algorithm for uterine cervical pap smears in order to mitigate such burdens of medical experts. In the preneoplastic state cytodiagnosis images, it is important to differentiate three main areas - background, cytoplasm and nucleus. Thus, we apply lighting compensation and $3{\times}3$ mask of B channel in order to restore damaged image and remove noises respectively. The cell object is obtained from those clean binarized images with Grossfire algorithm. When there are clusters of cells, the target nucleus can be obtained with repetitive binarization of R channel brightness. In our experiment of using uterine cervical pap smears of 400 magnifications that is common in the diagnostic cytology, our method is able to extract 40 nucleus out of 45 population successfully.

A Joint Power Allocation and Scheduling Algorithm for CDMA-based High-rate Packet Data Systems (CDMA기반 고속 패킷 데이터 전송 시스템을 위한 전력제어가 결합된 스케쥴링 알고리즘)

  • Koo In-Soo;Kim Ki-Seon
    • Journal of Internet Computing and Services
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    • v.7 no.3
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    • pp.41-51
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    • 2006
  • In the case of CDMA-based packet data systems such as 1xEV-DO which are designed to support high rate services, BSs transmit data packets with a maximum power based on time multiplexing mode such that only one user can be serviced at a time. In this paper, we propose a joint power allocation and scheduling algorithm for 1xEV-DO-like systems in which we adopt a code division multiplexing (CDM) transmission method in the downlink common channel in order to utilize channel orthogonality such that we can serve more than one user at a time slot especially when there exist remaining resources after serving the firstly selected user by the scheduler. Simulation results demonstrate that the proposed scheme can improve the performances of conventional schemes such as the maximum rate and the proportional fair algorithms.

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A new precast wall connection subjected to monotonic loading

  • Vaghei, Ramin;Hejazi, Farzad;Taheri, Hafez;Jaafar, Mohd Saleh;Ali, Abang Abdullah Abang
    • Computers and Concrete
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    • v.17 no.1
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    • pp.1-27
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    • 2016
  • Final construction project cost is significantly determined by construction rate. The Industrialized Building System (IBS) was promoted to enhance the importance of prefabrication technology rather than conventional methods in construction. Ensuring the stability of a building constructed by using IBS is a challenging issue. Accordingly, the connections in a prefabricated building have a basic, natural, and essential role in providing the best continuity among the members of the building. Deficiencies of conventional precast connections were observed when precast buildings experience a large induced load, such as earthquakes and other disasters. Thus, researchers aim to determine the behavior of precast concrete structure with a specific type of connection. To clarify this problem, this study investigates the capacity behavior of precast concrete panel connections for industrial buildings with a new type of precast wall-to-wall connection (i.e., U-shaped steel channel connection). This capacity behavior is compared with the capacity behavior of precast concrete panel connections for industrial buildings that used a common approach (i.e., loop connection), which is subjected to monotonic loading as in-plane and out-of-plane loading by developing a finite element model. The principal stress distribution, deformation of concrete panels and welded wire mesh (BRC) reinforcements, plastic strain trend in the concrete panels and connections, and crack propagations are investigated for the aforementioned connection. Pushover analysis revealed that loop connections have significant defects in terms of strength for in-plane and out-of-plane loads at three translational degrees of freedom compared with the U-shaped steel channel connection.

The Algorithm on Channel Converting and Monitoring of the Remote Controlled Transceiver (원격제어 송수신기의 채널변환 및 모니터링에 대한 알고리즘)

  • 조학현;최조천;김기문
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.05a
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    • pp.266-271
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    • 1999
  • The purpose in this study has to development the system on increasing operation of old-typed transceiver for solve the question that limited allocation frequencies and continuesly icreasment of traffic. Therefore, we are desigened the remote control system that has the function for variable channels, PTT and monitoring of transmission power and frequencies. Exchange of control data is to hold in common the twist two-wire or telephone line for the voice transmission. The H/W is consist of FSK and MCS-51 processor which are up-down control of channel, n control and monitoring display by serial data transmission. According to the simplex traffic operation is designed the algorithm of serial data transmission by sequential transmission sequence and protocol. The S/W of sequential transmission sequence is designed to usefully the intergrated communications system which is able to connection between the multi-transceiver and multi-terminal by master processor.

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The Design of CMOS-based High Speed-Low Power BiCMOS LVDS Transmitter (CMOS공정 기반의 고속-저 전압 BiCMOS LVDS 구동기 설계)

  • Koo, Yong-Seo;Lee, Jae-Hyun
    • Journal of IKEEE
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    • v.11 no.1 s.20
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    • pp.69-76
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    • 2007
  • This paper presents the design of LVDS (Low-Voltage-Differential-Signaling) transmitter for Gb/s-per-pin operation. The proposed LVDS transmitter is designed using BiCMOS technology, which can be compatible with CMOS technology. To reduce chip area and enhance the robustness of LVDS transmitter, the MOS switches of transmitter are replaced with lateral bipolar transistor. The common emitter current gain($\beta$) of designed bipolar transistor is 20 and the cell size of LVDS transmitter is $0.01mm^2$. Also the proposed LVDS driver is operated at 1.8V and the maximum data rate is 2.8Gb/s approximately In addition, a novel ESD protection circuit is designed to protect the ESD phenomenon. This structure has low latch-up phenomenon by using turn on/off character of P-channel MOSFET and low triggering voltage by N-channel MOSFET in the SCR structure. The triggering voltage and holding voltage are simulated to 2.2V, 1.1V respectively.

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Internet Broadcasting As a Place for Conspiracy Theory or Discussion: Focus on BJ Hammer Wife of Afreeca TV (음모론 혹은 토론의 장으로써의 인터넷 방송: Afreeca TV의 망치부인을 중심으로)

  • Han, Sukhee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.4
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    • pp.61-70
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    • 2017
  • This study analyzes various aspects of the Internet broadcasting that has rapidly increased in South Korea recently. Due to the development of technology, the Internet Broadcasting industry that ordinary viewers do the broadcasting themselves has appeared. Today, the most popular platform of the Internet broadcasting in South Korea is "Afreeca TV", which allows BJs do broadcasting in their channel with own contents. Related to current chaotic Korean society, Current Affairs/Politics becomes one of the new popular genres. Specifically, this study focuses on BJ Hammer Wife as a case study, who is famous in the Current Affairs/Politics industry. Then it examines what characteristics of her channel, her opinions, and the method of communication with common viewers implicate messages regarding the freedom of speech in South Korea. Throughout this, it explores that the Internet Broadcasting functions as a place for conspiracy or discussion, and discusses the blueprint of the Internet broadcasting.

A Study on Appropriate S-box of DES in Radio Channel (무선채널에 적합한 DES의 S박스에 관한 연구)

  • Park, Mi-Og;Choi, Yeon-Hee;Jun, Moon-Seog
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1C
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    • pp.18-24
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    • 2004
  • Nowadays, the development of wireless communications provides a convenience for many people. On the other hand, the openness of wireless communications poses serious security threats and the security of wireless communications is necessary to support the secure communication channel. The common security method on wireless is the stream cipher that generates the pseudorandom number. In this paper, we propose the usage of the nonlinear function S-box and the mechanism according to it in stream cipher as the study to securely protect data transferred on wireless communications. Besides, it goes abreast a study on S-box with the best random characteristic among the used S-boxes on wireless communications. By means of test, we investigate the most appropriate S-box of DES on wireless communications environment and prove the efficiency of the proposed model by comparing and analysis of the randomness of the based stream cipher and the proposed model.