• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.31-34
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• 2012

In MANET, frequent movement of nodes causes the dynamic network topology changes. Therefore the routing protocol, which is very stable to effectively respond the changes of the network changes, is required. Moreover, the existing cluster-based routing protocol, that is the hybrid approach, has routing delay due to the re-electing of the cluster header. In addition, the routing table of CBRP has all only one hop distant neighbor nodes. PCBRP, proposed in this paper, ties two clusters in one pair of clusters to make longer radius. Then the pair of the cluster headers manages and operates corresponding member nodes. When they route nodes in the paired cluster internally, PCBRP reduces the delay by requesting a route. Therefore PCBRP shows improved total delay of the network and improved performance of packet transmitting rate.

• Korean Journal of Plant Taxonomy
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• 제46권4호
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• pp.378-391
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• 2016

Eighteen morphological characters from 40 populations and ten isozyme loci from 35 populations of Sedum latiovalifolium and related species were examined to investigate the degree of morphological and genetic variation. The high-frequency marker alleles $MDH-2^a$ and $PGI-1^a$ in S. aizoon, S. kamtschaticum, and S. zokuriense did not appear in the populations of S. latiovalifolium. In addition, the high-frequency allele ($MDH-2^c$) in S. latiovalifolium appeared at a very low frequency in other subg. aizoon species. Thus, the isozyme data did not support a hybrid origin of S. latiovalifolium from S. aizoon with S. kamtschaticum. The results of an unweighted pair-group method using the arithmetic average method and a principal components analysis using morphological data also did not support a hybrid origin of S. latiovalifolium. However, our data strongly suggest that some individuals from the populations found in the Gumdaebong area were most likely hybrids due to introgression between S. latiovalifolium and S. kamtschaticum or S. aizoon and S. kamtschaticum.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제21권9호
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• pp.1037-1044
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• 2010

In this paper, a new size-reduced, wideband ring-hybrid coupler is presented, and a design of a planar single-balanced doubler using the ring-hybrid is shown. This ring-hybrid coupler employs a pair of ultra-wideband transitions for phase inversion, which consists of in-phase and out of-phase transitions providing a good amplitude and phase balances for wide frequency ranges. The implemented ring-hybrid is 65 % smaller than conventional ring-hybrids, and provides 92.5 % and 81.3 % bandwidth at $\sum$ and $\Delta$ ports, respectively. Thanks to good amplitude and phase balances over wide bandwidth, the ring-hybrid can be applied to implement various balanced components. The implemented single-balanced doubler utilizing the ring-hybrid exhibits typical conversion loss of 10.5 dB for the output frequency range of 4~12 GHz with fundamental suppression level of 30 dB. The performance was also well-predicted with the nonlinear circuit simulation.

• Korean journal of applied entomology
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• 제28권4호
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• pp.229-236
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• 1989

A combined field release of indigenous larvivoroug fish (Aplocheilus latipes) and hybrid herbivore (Tilapia mossambicus miloticus) was conducted to determine the effectiveness of biological control, in particular, against malaria vector (anopheles sinensis), breeding in weedy habitat of rice fields at the University rice paddies at Suwon during the period of June through September in 1988. A combined fish introduction at the release rate of 2.0 fish per $M^{2}$ for Aplocheilus and 1-pair $10M^{2}$ water surface for Tilapia resuited in 70.8% Anopheles larval reducton in a week period, the rates of rontrol increased to 73. 5% and 80.2% in 4th and 5th week respectively after the fish introdurtion, maintaining mosquito suppression in range of 80~82% control after the 5th week against Anopheles and Culex spp. combined. In a single fish treatment with Aplocheilus at 2.0 $fish/M^{2}$ release rate, Anopheles larval reduction ranged on the average 51.4~56.5%in 4 wrek period which was later integratpd with B.t.i. (Rl53.78) treatment at 1.0 kg/ha dosage rate to suppress vector mosquito population down and the the results was compared with that of combined fish introdurtion.

• Journal of Institute of Control, Robotics and Systems
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• 제11권7호
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• pp.602-608
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• 2005

In the virtual environment, force feedback to the human operator makes virtual experiences more realistic. To ensure the safe operation and enhance the haptic feeling, stability should be guaranteed. Both motors and brakes are commonly used for haptic devices. Motors can generate a torque in any direction, but they can make the system active during operation, thus leading to instability. Brakes can generate a torque only against their rotation, but they dissipate energy during operation, which makes the system intrinsically stable. Consequently, motors and brakes are complementing each other. In this research, a two degree-of-freedom (DOF) haptic device equipped with motors and brakes has been developed to provide better haptic effects. Each DOF is actuated by a pair of motor and brake. Modeling of the environment and the control method are needed to utilize both actuators. Among various haptic effects, contact with the virtual wall, representation of friction and representation of plastic deformation have been investigated extensively in this paper. It is shown that the hybrid haptic device is more suited to some applications than the motor-based haptic device.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권9호
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• pp.2081-2100
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• 2013

In this paper, we propose a cooperative hybrid spectrum sharing protocol by jointly considering interweave (opportunistic) and underlay schemes. In the proposed protocol, secondary users can access the licensed spectrum along with the primary system. Our network scenario comprises a single primary transmitter-receiver (PTx-PRx) pair and a group of M secondary transmitter-receiver (STx-SRx) pairs within the transmission range of the primary system. Secondary transmitters are divided into two groups: active and inactive. A secondary transmitter that gets an opportunity to access the secondary spectrum is called "active". One of the idle or inactive secondary transmitters that achieves the primary request target rate $R_{PT}$ will be selected as a best decode-and-forward (DF) relay (Re) to forward the primary information when the data rate of the direct link between PTx and PRx falls below $R_{PT}$. We investigate the ergodic capacity and outage probability of the primary system with cooperative relaying and outage probability of the secondary system. Our theoretical and simulation results show that both the primary and secondary systems are able to achieve performance improvement in terms of outage probability. It is also shown that ergodic capacity and outage probability improve when the active secondary transmitter is located farther away from the PRx.

• Current Optics and Photonics
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• 제2권6호
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• pp.540-546
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• 2018

We propose an implementation scheme for an optical encryption system with hybrid-pattern random keys. In the encryption process, a pair of random phase keys composed of a white-noise phase key and a structured phase key are positioned in the input plane and Fourier-spectrum plane respectively. The output image is recoverable by digital reconstruction, using the conjugate of the encryption key in the Fourier-spectrum plane. We discuss the system encryption performance when different combinations of phase-key pairs are used. To measure the effectiveness of the proposed method, we calculate the statistical indicators between original and encrypted images. The results are compared to those generated from a classical double random phase encoding. Computer simulations are presented to show the validity of the method.

• The Journal of the Korea institute of electronic communication sciences
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• 제12권1호
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• pp.189-194
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• 2017

The reversibility of a quantum logic circuit can be realized when two reversible conditions of information reversible and energy reversible circuits are satisfied. In this paper, we have modeled the computation cycle required to recover the information reversibility from the multivalued quantum logic to the original state. For modeling, we used a function embedding method that uses a unitary switch as an arithmetic exponentiation switch. In the quantum logic circuit, if the adjoint gate pair is symmetric, the unitary switch function shows the balance function characteristic, and it takes 1 cycle operation to recover the original information reversibility. Conversely, if it is an asymmetric structure, it takes two cycle operations by the constant function. In this paper, we show that the problem of 2-cycle restoration according to the asymmetric structure when the hybrid MCT gate is realized with the ternary M-S gate can be solved by equivalent conversion of the asymmetric gate to the gate of the symmetric structure.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.470-473
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• 2004

This paper presents conducted emission noise measurement from electronic equipment in frequency range of 1 MHz up to 30 MHz by small loop antenna. Small loop antenna measurement method can measure common-mode (CM) and differential-mode (DM) component of the noise on a pair of power line at the same time. The CM and DM can be measured separately. The theory of this measurement method is introduced and analyzed. The measured results were compared with the conventional measurement by Line Impedance Stabilization Network (LISN) and result a good trend between those methods.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.101-105
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• 2004

A number of Chinese, Japanese and European silkworm strains with coarse size filament were used for breeding the coarse size variety. Through cross breeding combined with pedigree selection within thirteen generations, a pair of coarse size silkworm variety, named ${CU_1}{\times}{CU_2}$, was obtained after five years. Laboratory trials showed that the filament size of its 4F_1$ hybrid was over 4.3 D, and the other economic characters were also good.