• Journal of the Institute of Convergence Signal Processing
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• v.9 no.2
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• pp.154-158
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• 2008

Autonomous business card exchange system using ZigBee with low power and short range was configured In the autonomous business card exchange system characterized as full mesh network in which every node exchanges each information one by one, it is necessary to reduce the time taken for information to be exchanged. In this paper, the novel method where the node ID is exchanged based on CSMA/CA and then the information of each node is broadcast to other nodes according to the ID list based on FIFO. The time required for exchanging information using the proposed method was analyzed and compared with the direct exchange method based on CSMA/CA. The results show that it takes less time in the proposed method than the direct exchange time.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.3
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• pp.1-9
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• 2016

The study examined the effects of shift pattern and expertise on perceived workload and performance for aviation security screeners. 18 security screeners participated in this study, in which data were analyzed by dividing them into two groups (experts vs. less-experts). We measured their perceived workloads and performances (i.e., reading time through X-ray) as a function of shift pattern and time condition. As a result, highly experienced screeners (experts) showed high workload during the morning shift, while lowly experienced screeners (less-experts) reported high workload during the full-day and the afternoon shifts. In addition, less-experts took a longer time to inspect the baggage when they worked for the full-day and the afternoon shifts. Particularly, in the last time slot of the full-dat shift, expert screeners had a high workload, while both groups showed a high-level of workload at around 17:30 in the afternoon shift.

• Journal of Communications and Networks
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• v.17 no.3
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• pp.286-295
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• 2015

Avionic databuses fulfill a critical function in the connection and communication of aircraft components and functions such as flight-control, navigation, and monitoring. Ethernet-based avionic databuses have become the mainstream for large aircraft owning to their advantages of full-duplex communication with high bandwidth, low latency, low packet-loss, and low cost. As a new generation aviation network communication standard, avionics full-duplex switched ethernet (AFDX) adopted concepts from the telecom standard, asynchronous transfer mode (ATM). In this technology, the switches are the key devices influencing the overall performance. This paper reviews the avionic databus with emphasis on the switch architecture classifications. Based on a comparison, analysis, and discussion of the different switch architectures, we propose a new avionic switch design based on a time-division switch fabric for high flexibility and scalability. This also merges the design concept of space-partition switch fabric to achieve reliability and predictability. The new switch architecture, called space partitioned shared memory switch (SPSMS), isolates the memory space for each output port. This can reduce the competition for resources and avoid conflicts, decrease the packet forwarding latency through the switch, and reduce the packet loss rate. A simulation of the architecture with optimized network engineering tools (OPNET) confirms the efficiency and significant performance improvement over a classic shared memory switch, in terms of overall packet latency, queuing delay, and queue size.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.3887-3907
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• 2015

This paper introduces a full duplex single secondary user multiple-input multiple-output (FD-SSU-MIMO) cognitive radio network, where secondary user (SU) opportunistically accesses the authorized spectrum unoccupied by primary user (PU) and transmits data based on FD-MIMO mode. Then we study the network achievable average sum-rate maximization problem under sum transmit power budget constraint at SU communication nodes. In order to solve the trade-off problem between SU's sensing time and data transmission time based on opportunistic spectrum access (OSA) and the power allocation problem based on FD-MIMO transmit mode, we propose a simple trisection algorithm to obtain the optimal sensing time and apply an alternating optimization (AO) algorithm to tackle the FD-MIMO based network achievable sum-rate maximization problem. Simulation results show that our proposed sensing time optimization and AO-based optimal power allocation strategies obtain a higher achievable average sum-rate than sequential convex approximations for matrix-variable programming (SCAMP)-based power allocation for the FD transmission mode, as well as equal power allocation for the half duplex (HD) transmission mode.

• Journal of Korea Multimedia Society
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• v.7 no.11
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• pp.1556-1563
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• 2004

In this paper, we propose an efficient full mesh topology aggregation method in PNNI networks. The proposed scheme can search multi-links efficiently using the depth priority method based on hop count instead of searching the all links. To do this, we propose a modified line segment algorithm using two line segment method that represents two points which consist of delay-bandwidth pair to reduce topology information and provide a flexibility to the multiple-links aggregation. And we apply it to current full mesh topology aggregation. To evaluate performance of the proposed scheme, we compare/analyze the current method with the proposed scheme with respect to call success rate, access time and crank back rate. The result is that the proposed scheme is better than the current scheme in performance.

• Journal of Yeungnam Medical Science
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• v.35 no.2
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• pp.187-191
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• 2018

Background: Respiratory distress syndrome (RDS) is a one of the most common cause of respiratory morbidity and mortality in neonates. This study was conducted to investigate the risk factors for RDS in full-term neonates. Methods: We conducted this retrospective study using medical records. The study group included 80 full-term neonates diagnosed with RDS and hospitalized in the neonatal intensive care unit between January 2012 and December 2016, at Yeungnam University Hospital. We analyzed sex, gestational age, birth weight, delivery method, maternal age, number of pregnancy, history of abortion, and complication of pregnancy. The control group included 116 full-time neonates who were hospitalized with jaundice during the same period. Results: The incidence of full-term RDS was more common in males (odds ratio [OR], 3.288; 95% confidence interval [CI], 1.446-7.479), cesarean section (OR, 15.03; 95% CI, 6.381-35.423), multiparity (OR, 4.216; 95% CI, 1.568-11.335). The other factors rendered no significant results. Conclusion: The risk factors for RDS in full-tern neonates were identified as male sex, cesarean section, and multiparity. Further studies involving more institutions are needed to clarify the risk factors for RDS in full-term infants.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.6 s.312
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• pp.60-70
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• 2006

Currently, Scalable Video Coding (SVC) is being standardized. By using scalability of SVC, QoS managed video streaming service is enabled in heterogeneous networks even with only one original bitstream. But current SVC is insufficient to dynamic video conversion for the scalability, thereby the adaptation of bitrate to meet a fluctuating network condition is limited. In this paper, we propose dynamic full-scalability conversion method for QoS adaptive video streaming in H.264/AVC SVC. To accomplish full scalability dynamic conversion, we propose corresponding bitstream extraction, encoding and decoding schemes. On the encoder, we newly insert the IDR NAL to solve the problems of spatial scalability conversion. On the extractor, we analyze the SVC bitstream to get the information which enable dynamic extraction. By using this information, real time extraction is achieved. Finally, we develop the decoder so that it can manage changing bitrate to support real time full-scalability. The experimental results showed that dynamic full-scalability conversion was verified and it was necessary for time varying network condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8C
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• pp.762-768
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• 2005

This paper proposes new space-time block codes achieving full rate and full diversity for QAM and quasi-static Rayleigh fading channels when using any number of transmit antennas larger than 3 transmit antennas. These codes are constructed by serially concatenating the constellation rotating $precoders^{[4,5]}$ with the Alamouti scheme$3^{[3]}$ Bike the conventional A-ST-CR code$^{[6,7]}$. Computer simulations show that the proposed codes achieve approximately 1.3dB, 1.4dB and 1.5dB larger coding gains than the ST-CR $codes^{[4,5]}$ for QPSK with 3, 4 and 5 transmit antennas, respectively, and about 3dB for 16QAM with 3 transmit antennas.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1075-1080
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• 2003

Design and fabrication process of a full inorganic electroluminescent microdislay based on aluminum / nanostructured porous silicon reverse biased light emitting Schottky diodes are discussing. Being of a solid state construction. this micro-display is cost-effective, thin and light in weight due to very simple device architecture. Its benefits include also super high resolution, wide viewing angles, fast response time and wide operating temperature range. The advantages of full integration of a LED-array and driving circuitry onto a Si-chip will be also discussed.

• Journal of Embryo Transfer
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• v.2 no.1
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• pp.22-26
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• 1987

When the dairy cattle are genetically improved by embryo transfer, generation intervals can be reduced since sires are selected by their full-sister's records rather than by their daughter's records and selection intensity increases because only donor cows and sires for them are selected. In addition by embryo transfer many number of full-sisters and full-sisters are produced at the same time, resulting in the increase in the accuracy of selection.