• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.1
• /
• pp.71-76
• /
• 2014

In this paper, we proposed the 1-channel monopulse receiver which has the new configuration and described the operation procedures. Also, we compared and analyzed the proposal receiver and the general 3-channel monopulse receiver. As a result, it is apparent that the monopulse ratio of the proposal receiver is equal to that of the 3-channel monopulse receiver. The proposal receiver achieve the simple receiver configuration and the simple tracking procedures, as contrasted with the 3-channel monopulse receiver. Also, the proposal receiver has advantages in terms of size, weight, cost and power. Because the proposal monopulse receiver require 1-channel receiver and need not the signal processor in comparison with 3-channel monopulse receiver which require 3-channel receiver and need the signal processor.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.2
• /
• pp.628-646
• /
• 2016

This paper proposes a novel channel assignment scheme that is based on finite projective plane (FPP) theory. The proposed scheme involves using a Markov chain model to allocate N channels to N users through intermixed channel group arrangements, particularly when channel resources are idle because of inefficient use. The intermixed FPP-based channel group arrangements successfully related Markov chain modeling to punch through ratio formulations proposed in this study, ensuring fair resource use among users. The simulation results for the proposed FPP scheme clearly revealed that the defined throughput increased, particularly under light traffic load conditions. Nevertheless, if the proposed scheme is combined with successive interference cancellation techniques, considerably higher throughput is predicted, even under heavy traffic load conditions.

• The Korean Journal of Pain
• /
• v.24 no.3
• /
• pp.131-136
• /
• 2011

Background: Pregabalin is an anticonvulsant and analgesic agent that interacts selectively with the voltage-sensitive-$Ca^{2+}$-channel alpha-2-delta subunit. The aim of this study was to evaluate whether the analgesic action of intrathecal (IT) pregabalin is associated with KATP channels in the rat formalin test. Methods: IT PE-10 catheters were implanted in male Sprague-Dawley rats (250.300 g) under inhalation anesthesia using enflurane. Nociceptive behavior was defined as the number of hind paw flinches during 60 min after formalin injection. Ten min before formalin injection, IT drug treatments were divided into 3 groups: normal saline (NS) $20\;{\mu}l$ (CON group); pregabalin 0.3, 1, 3 and $10\;{\mu}g$ in NS $10\;{\mu}l$ (PGB group); glibenclamide $100\;{\mu}g$ in DMSO $5\;{\mu}l$ with pregabalin 0.3, 1, 3 and $10\;{\mu}g$ in NS $5\;{\mu}l$ (GBC group). All the drugs were flushed with NS $10\;{\mu}l$. Immunohistochemistry for the $K_{ATP}$ channel was done with a different set of rats divided into naive, NS and PGB groups. Results: IT pregabalin dose-dependently decreased the flinching number only in phase 2 of formalin test. The log dose response curve of the GBC group shifted to the right with respect to that of the PGB group. Immunohistochemistry for the $K_{ATP}$ channel expression on the spinal cord dorsal horn showed no difference among the groups 1 hr after the formalin test. Conclusions: The antinociceptive effect of pregabalin in the rat formalin test was associated with the activation of the $K_{ATP}$ channel. However, pregabalin did not induce $K_{ATP}$ channel expression in the spinal cord dorsal horn.

• Korean Journal of Acupuncture
• /
• v.28 no.4
• /
• pp.41-48
• /
• 2011

Objectives : This study aimed to explore the passive multi-channel time series analysis method by measuring bio-potentials of acupuncture point and the peripheral region Methods : Bio-potential was measured at ST36 and the peripherical region of ST36 of 5 healthy volunteers at three times. The diagram of the potential changes over time were smoothed by moving average method and similarities of ST36 and the other points were calculated. Results : In the normal weight group, bio-potential similarity tended to decrease in proportion to the distance from the acupuncture point. In the obesity group, bio-potential similarity appeared in a very wide area. Bio-potential similarity had positive correlation with BMI value. Conclusions : The passive multi-channel time series analysis method showed the possibility be appropriate for the electrical characteristics study of meridians.

• Journal of Communications and Networks
• /
• v.12 no.5
• /
• pp.411-432
• /
• 2010

We consider three different secure broadcasting scenarios: i) Broadcast channels with common and confidential messages (BCC), ii) multi-receiver wiretap channels with public and confidential messages, and iii) compound wiretap channels. The BCC is a broadcast channel with two users, where in addition to the common message sent to both users, a private message, which needs to be kept hidden as much as possible from the other user, is sent to each user. In this model, each user treats the other user as an eavesdropper. The multi-receiver wiretap channel is a broadcast channel with two legitimate users and an external eavesdropper, where the transmitter sends a pair of public and confidential messages to each legitimate user. Although there is no secrecy concern about the public messages, the confidential messages need to be kept perfectly secret from the eavesdropper. The compound wiretap channel is a compound broadcast channel with a group of legitimate users and a group of eavesdroppers. In this model, the transmitter sends a common confidential message to the legitimate users, and this confidential message needs to be kept perfectly secret from all eavesdroppers. In this paper, we provide a survey of the existing information-theoretic results for these three forms of secure broadcasting problems, with a closer look at the Gaussian multiple-input multiple-output (MIMO) channel models. We also present the existing results for the more general discrete memoryless channel models, as they are often the first step in obtaining the capacity results for the corresponding Gaussian MIMO channel models.

• Journal of Broadcast Engineering
• /
• v.8 no.2
• /
• pp.163-171
• /
• 2003

In this paper, we develop an approach toward Joint Source-Channel Coding for MPEG-4(Moving picture Experts Group) based video coding In fixed and mobile reception environment. We have considered channel environment of AWGN and mobile reception. The source coder used MPEG-4 video. the channel coder used RCPC(Rate Compatible Punctured Convolution) and the modulation method used QPSK(Quadrature Phase Shift Keying) modulation. This study determined optimum Trade-off point between source bit rate and channel coding rate In variable channel states. We compared Joint Source/channel Coding method and general constant bit rate transmission. In this results, Joint Source/channel Coding was appeared better performance than constant bit rate transmission.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.2
• /
• pp.583-599
• /
• 2015

We apply the Bayesian matching pursuit (BMP) algorithm to the estimation of time-frequency selective channels in orthogonal frequency division multiplexing (OFDM) systems. By exploiting prior statistics and sparse characteristics of propagation channels, the Bayesian method provides a more accurate and efficient detection of the channel status information (CSI) than do conventional sparse channel estimation methods that are based on compressive sensing (CS) technologies. Using a reasonable approximation of the system model and a skillfully designed pilot arrangement, the proposed estimation scheme is able to address the Doppler-induced inter-carrier interference (ICI) with a relatively low complexity. Moreover, to further reduce the computational cost of the channel estimation, we make some modifications to the BMP algorithm. The modified algorithm can make good use of the group-sparse structure of doubly selective channels and thus reconstruct the CSI more efficiently than does the original BMP algorithm, which treats the sparse signals in the conventional manner and ignores the specific structure of their sparsity patterns. Numerical results demonstrate that the proposed Bayesian estimation has a good performance over rapidly time-varying channels.

• Transactions of the Korean hydrogen and new energy society
• /
• v.30 no.5
• /
• pp.448-454
• /
• 2019

This paper presents a high-efficiency design technique for developing the serialized models of a single-channel pump based on the diameter, flow rate and head as the main performance parameters. The variation in pump performance by changing of the single-channel pump geometry was predicted based on computational fluid dynamics (CFD). Numerical analysis was conducted by solving three-dimensional steady Reynolds-averaged Navier-Stokes equations with the shear stress transport (SST) turbulence model. The tendencies of the hydraulic performance depending on the pump geometry scale were analyzed with the fixed rotational speed. These performances were expressed and evaluated as the functionalization for designing the serialized models of a single-channel pump in this work.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.12
• /
• pp.3-9
• /
• 2015

In this paper, we propose the operation procedures of the 1-channel monopulse receiver which achieves the new configuration. Also, we analyzed the monopulse ratio and the target angle accuracy of the fabricated receiver by using the monopulse signal generator developed for verifying the proposal equipment. As a result, it is apparent that the monopulse ratio of the proposal receiver is equal to that of the 3-channel monopulse receiver. Also, the fabricated receiver exhibits the target angle accuracy with fewer than 0.1 RMS. The proposal receiver achieves the simple receiver configuration and the simple tracking procedures, as contrasted with the 3-channel monopulse receiver. Also, the proposal receiver has advantages in terms of size, weight, cost and power. Because the proposal monopulse receiver requires 1-channel receiver and needs not the signal processor in comparison with 3-channel monopulse receiver which requires 3-channel receiver and need the signal processor.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.40 no.10
• /
• pp.51-58
• /
• 2003

In this paper, we propose a group scheduling scheme to efficiently utilize network resources for core nodes in optical burst switching networks. This scheme schedules multiple bursts utilizing an interval graph to obtain the maximum stable set using the information such as arrival times and burst lengths from the collected header packets. Simultaneous scheduling of multiple bursts in a scheduling window results in lower burst loss probability and increased channel utilization than those proposed previously using one-to-one mapping. Simulation results for both cases of variable and fixed burst sizes show that the group scheduling scheme is better than the immediate scheduling, so called Latest Available Unused Channel with Void Filling, scheme in both performance metrics above mentioned.