• Journal of Institute of Control, Robotics and Systems
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• v.10 no.11
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• pp.1052-1057
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• 2004

Bluetooth technology is essentially a method for wireless connectivity of a diverse set of devices ranging from PDAs, mobile phone, notebook computers, to another equipments, The bluetooth system both point-to point connection and point-to multipoint connection. In point-to multipoint connection, the channel is shared among several bluetooth devices. Two or more devices sharing the same channel form a piconet. There one master device and up to seven active slave devices in a piconet. The radio operates in the unlicensed 2.45GHz ISM band. This allows users who travel world-wide to use bluetooth equipments anywhere. Since the link is based on frequency-hop spread spectrum, multiple channels can exist at the same time. The bluetooth standard ha s been suggested that bluetooth equipments can be used in the short-range, maximum 100 meters. It has been defined that the time takes to setup and establish a bluetooth connection among devices is 10 seconds. It is a long time and may be a cause to lose a chance of finding other non-fixed devices. We propose a routing protocols for scatternets which can be used to control a mobile units(MUs) in this network. The proposed routing protocol is composed of two kinds of bluetooth information, access point(AP) and MU.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1826-1829
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• 2005

Recent advancement in wireless communications and electronics has enabled the development of low power sensor network. Wireless sensor network are often used in remote monitoring control applications, health care, security and environmental monitoring. Wireless sensor networks are an emerging technology consisting of small, low-power, and low-cost devices that integrate limited computation, sensing, and radio communication capabilities. Sensor network platform for health care has been designed, fabricated and tested. This system consists of an embedded micro-controller, Radio Frequency (RF) transceiver, power management, I/O expansion, and serial communication (RS-232). The hardware platform uses Atmel ATmega128L 8-bit ultra low power RISC processor with 128KB flash memory as the program memory and 4KB SRAM as the data memory. The radio transceiver (Chipcon CC1000) operates in the ISM band at 433MHz or 916MHz with a maximum data rate of 76.8kbps. Also, the indoor radio range is approximately 20-30m. When many sensors have to communicate with the controller, standard communication interfaces such as Serial Peripheral Interface (SPI) or Integrated Circuit ($I^{2}C$) allow sharing a single communication bus. With its low power, the smallest and low cost design, the wireless sensor network system and wireless sensing electronics to collect health-related information of human vitality and main physiological parameters (ECG, Temperature, Perspiration, Blood Pressure and some more vitality parameters, etc.)

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.280-283
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• 2000

Users of computer interfaced with the LAN use the same printer with time sharing. Alternatively, Hey use the multi-user printer interface to print in the office which can't have LAN system due to the great expenses. Otherwise they have to connect directly moving the printer to computer. In this papaer, we present a new printer interface equipment which can interface a printer and multi computers through wireless using the radio frequency of about 430MHz. The tranceivers of the equipment consist of two part: one part is installed in parallel port of computer and other part is installed in Centronix port of printer. Their maximum data rate is 9600bps and the communication area is about 50 meters in best case.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1040-1043
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• 2000

The genomic mapping of Red Jungle Fowl (Gallus gallus), local Village Chicken, and broiler was carried out by random amplified polymorphism DNA (RAPD) technique. Two different sets of arbitrary primers were used (Operon OPA01-20 and Genemed GM01-50). All the genomes of the three species of chickens were amplified with OPA01-20 primers. The genomes of the Red Jungle Fowl and local Village Chicken were further amplified with GM01-50 primers. Analysis of the results based on band sharing (BS) and the molecular size of individually amplified DNA fragments showed that Red Jungle Fowl and local Village Chicken shared the species similarity of 66% with Operon primers 01-20, 64% between local Village Chicken and broiler, and 63% when DNA bands between Red Jungle Fowl and broiler were compared. With GM01-50, the BS between Red Jungle Fowl and local village chicken increased to 72%. The results showed that the local village chicken is more closely related to Red Jungle Fowl than to broiler in the genetic distance. On the other hand, broiler is 1% closer in genetic distance to local village chicken than to Red Jungle Fowl. The results also indicated that primers like OPA-7, 8 and 9 can be used as species specific DNA markers for these three species of chickens.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.5
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• pp.1012-1018
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• 2005

According as computer industry develops and the Internet is spread information interchange between remote users video conference system that can exchange multimedia data such as voice as well as simplicity text data or burn by real-time appeared and is used in various field. However, most systems developed present have controversial points of that need expensive multi-point connection equipment or network resource of High band width. Hereupon, in this paper, designed and embody video conference system that can be stable and supplies multimedia information and screen public ownership environment of high-quality as software using minimum network resource without using expensive connection equipment.

• Journal of information and communication convergence engineering
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• v.18 no.1
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• pp.1-7
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• 2020

This paper proposes a fast-processing and low-cost hardware multiple input multiple output (MIMO) channel emulator. The channel emulator is an important component of hardware-based simulation systems. The novelty of this work is the use of sharing and pipelining functions to reduce hardware resource utilization while maintaining a high sample rate. In our proposed emulator, the samples are created sequentially and interpolated to ensure the sample rate is equal to the base band rate. The proposed 4 × 4 MIMO requires low-cost hardware resource so that it can be implemented on a single field-programmable gate array (FPGA) chip. An implementation on Xilinx Virtex-7 VX980T was found to occupy 10.47% of the available configurable slice registers and 12.58% of the FPGA's slice lookup tables. The maximum frequency of the proposed emulator is 758.064 MHz, so up to 560 different paths can be processed simultaneously to generate 560 × 758 million × 2 × 32 bit complex-valued fading samples per second.

• Development and Reproduction
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• v.23 no.4
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• pp.377-384
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• 2019

Genomic DNA extracted from representatives of two populations, Gunsan and Chinese, of Urechis spp. was amplified using PCR with several primers. The band-sharing (BS) value between individuals no. 05 from the Gunsan population and no. 22 from the Chinese population was 0.206, which was the lowest recognized value. Oligonucleotides primer OPC-04 revealed 44 unique loci, which distinguished the Chinese population. Primer OPB-17 allowed the discovery of 22 loci shared by the two populations, which were present in all samples. Based on the average BS results, individuals from the Gunsan population demonstrated lower BS values (0.661±0.012) than did those from the Chinese population (0.788±0.014; p<0.05). The shortest genetic distance (GD) displaying a noteworthy molecular difference was between individuals CHINESE no. 12 and no. 13 (GD=0.027). Individual no. 06 from the Gunsan population was most distantly related to CHINESE no. 22 (GD=0.703). A group tree of the two populations was constructed by UPGMA Euclidean GD analysis based on a total of 543 fragments generated using six primers. The explicit markers recognized in this study will be used for genetic analysis, as well as to evaluate the species security and proliferation of echiuran individuals in intertidal regions of the Korean Peninsula.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.879-884
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• 2012

In this paper, we analyze the sharing parameters in order to co-use of different communication systems in adjacent channels. We analyze the performance result according to various density of interfering transmitter and transmitter output in hetero systems. In order to get the relationship with between density of interfering transmitter and transmitter output, we consider the case that WiBro is an interfering transmitter an WLAN is a victim receiver. When the interferer density is 50/$km^2$ and the center frequency of WLAN and WiBro are 185 and 201MHz respectively, required guard band is 4MHz. Analyzed coexistence results may be widely applied into the technique developed to get the coexisting condition for wireless devices using many communication protocols in same frequency.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.1
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• pp.179-185
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• 2017

Communication technologies hold a significant place in the swarm flight of drones for surveillance, inspection of disasters and calamities, entertainment performances, and drone collaborations. A GCS(ground control station) for the control of drone swarms needs its devoted communication method to control a large number of drones at the same time. General drone controllers control drones by connecting transmitters and drones in 1:1. When such an old communication method is employed to control many drones simultaneously, problems can emerge with the control of many transmitter modules connected to a GCS and frequency interference among them. This study implemented a transmitter controller to control many drones simultaneously with a communication chip of 2.4GHz ISM band and a Cortex M4-based board. It also designed a GCS to control many transmitter controllers via a network. The hierarchical method made it possible to control many more drones. In addition, the problem with frequency interference was resolved by implementing a time- and frequency-sharing method, controlling many drones simultaneously, and adding the frequency hopping feature. If PPM and S.BUS protocol features are added to it, it will be compatible with more diverse transmitters and drones.

• ETRI Journal
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• v.43 no.3
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• pp.389-399
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• 2021

In this paper, we propose one-bit feedback-based distributed beamforming (DBF) techniques for simultaneous wireless information and power transfer in interference channels where the information transfer and power transfer networks coexist in the same frequency spectrum band. In a power transfer network, multiple distributed energy transmission nodes transmit their energy signals to a single energy receiving node capable of harvesting wireless radio frequency energy. Here, by considering the Internet-of-Things sensor network, the energy harvesting/information decoding receivers (ERx/IRx) can report their status (which may include the received signal strength, interference, and channel state information) through one-bit feedback channels. To maximize the amount of energy transferred to the ERx and simultaneously minimize the interference to the IRx, we developed a DBF technique based on one-bit feedback from the ERx/IRx without sharing the information among distributed transmit nodes. Finally, the proposed DBF algorithm in the interference channel is verified through the simulations and also implemented in real time by using GNU radio and universal software radio peripheral.