• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.190-196
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• 2009

In this paper, performance of a turbo-coded OFDM system is analyzed and simulated in a power line communication channel. Since the power line communication system typically operates in a hostile environment, turbo code has been employed to enhance reliability of transmitted data. The performance is evaluated in terms of bit error probability. As turbo decoding algorithms, MAP (maximum a posteriori), Max-Log-MAP, and SOVA (soft decision Viterbi output) algorithms are chosen and their performances are compared. From simulation results, it is demonstrated that Max-Log-MAP algorithm is promising in terms of performance and complexity. It is shown that performance is substantially improved by increasing the number of iterations and interleaver length of a turbo encoder. The results in this paper can be applied to OFDM-based high-speed power line communication systems.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.300-304
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• 2007

Wireless sensor networks represent a new and exciting communication paradigm which could have multiple applications in future wireless communication. Therefore, performance analysis of such a wireless sensor network paradigm is needed in complex wireless channel. Wireless networks could be an important means of providing ubiquitous communication in the future. In this paper, the BER performance of uniform distributed wireless sensor networks is evaluated in non-Gaussian noise channel. Using an analytical approach, the impact of Av. BER performance relating the coherent BPSK system at the end of a multi-hop route versus the spatial density of sensor nodes and impulsive noise parameters A and $\Gamma$ is evaluated.

• Asia pacific journal of information systems
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• v.13 no.1
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• pp.197-211
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• 2003

Intensified competition, splintered mass market, shortened product life cycles, and advanced technology and automation let companies to crease the IT investment to meet the changes, Although IT investment increased, IS didn't show the visible outcome. One of the major interest of IS managers is how to demonstrate the business value of the firm's investment in information technology. This paper proposes the revised model of Nelson & Cooprider(1990) regarding shared knowledge between IS and line groups. Knowledge can be shared through mutual trust, mutual influence and communication between these two groups. The revised model including communication is tested empirically using LISREL. The results show that shared knowledge mediated the relationship between IS performance and mutual trust, mutual influence and communication. And shared knowledge between IS and line groups increase IS performance. IS managers should develop mutual trust, mutual influence and communication between these groups to achieve more shared knowledge and higher IS performance.

• Proceedings of the IEEK Conference
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• summer
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• pp.269-273
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• 2004

This paper presents a comparative performance analysis of a network accelerator model based on M/M/l queuing system. It assumes the Poisson distribution as its input traffic load. The decoding delay is employed as a performance analysis measure. Simulation results based on the proposed model show only $15\%$ differences with respect to actual measurements on field traffic for BCM5820 accelerator device. The performance analysis model provides with reasonable hardware structure of network servers, and can be used to span design spaces statistically.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1451-1454
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• 2002

In recent years, there are growing concerns about land mobile satellite (LMS) communication systems and mobile stratospheric communication systems (SCS) for the purpose of service upgrade of personal and mobile communications in near future. It is important to possess accurate channel model for prediction of the above system performance. Thus, in this paper, we evaluate the bit error rates of a coded BPSK system based on realistic channel model which can be applied to stratospheric communication systems. The channel data was made by fitting the parameters of probability distribution model to measured data. This approach was proposed by Corraza〔1〕and modified by You〔2〕. And also the effects of channel codings on the system performance are analyzed. As results, we can get the performance curve characteristics on realistic Rician log-normal fading channels with various communication environments.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.3
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• pp.121-129
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• 2010

In this paper, we analyze effects of positions of relays on the performance of cooperative communication networks. From this, the best relays are chosen to assist transmitting the signal to the destination or to replace the source to retransmit the signal to the destination whenever the destination incorrectly receives the signal from the source. As the results, we show the significant improvement on performance of schemes choosing best relays, which is compared to the performance of other cooperative schemes. Moreover, the simulation results that match exactly with the theoretical results prove the correctness of the analysis.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.202-204
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• 2005

This paper is proposed genetic algorithm tuning(GAT) controller for high performance of induction motor drive. We employed GA to the classical PI controller. The approach having ability for global optimization and with good robustness, is expected to overcome some weakness of conventional approaches and to be more acceptable for industrial practices. The control performance of the GAT PI controller is evaluated by analysis for various operating conditions. The results of experiment prove that the proposed control system has strong high performance and robustness to parameter variation, and steady-state accuracy and transient response.

• International journal of advanced smart convergence
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• v.12 no.1
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• pp.9-17
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• 2023

Recently, IoT technology has been widely used in many industries. Also research on integrating IoT technology with IoT sensors is actively underway. One of the important challenges in IoT is to support low-latency communication. With the development of communication networks and protocols, a variety of protocols are being used, and their performance is improving. In this paper, we compare the performance and analyze the characteristics of some of the major communication protocols in IoT application, namely MQTT, HTTP, and HTTPS. IoT sensors acquired data by connecting an Arduino equipped with ESP8266 and a temperature and humidity sensor (DHT11). The server measured the performance by building servers for each protocol using AWS EC2. We analyzed the packets transmitted between the Arduino and the server during the data transmission. We measured the amount of data and transfer time. The measurement results showed that MQTT had the lowest data transmission time and data amount among the three protocols.

• Journal of Distribution Research
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• v.8 no.2
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• pp.67-84
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• 2003

This study suggests new perspective of interorganizational communication. The importance of communication quality is increasing because it affects performance of marketing channels. In perspective of information exchange, communication quality consists of accuracy, availability, timing, and credibility. In research model, the antecedents of communication quality adopt willingness of information sharing and capability of efficient communication. To examine effects of communication quality on channel performance, research model includes relation of communication quality and conflicts. For empirical test, relation of PC makers and their dealers is decided as a focal dyad. Findings indicate that overall hypotheses are supported except the relation of willingness of information sharing and communication quality.

• Journal of Korean Critical Care Nursing
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• v.15 no.1
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• pp.58-68
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• 2022

Purpose : This study aimed to provide basic data for developing strategies to improve the nursing performance of nurses working in the intensive care unit by identifying the degree of their communication ability, job satisfaction, organization commitment, and nursing performance, and the relation between each of these variables in the intensive care unit by examining the factors affecting nursing performance. Methods : The participants comprised of 150 nurses working in the intensive care unit in two advanced general hospitals. Data were collected using structured questionnaires and analyzed using a t-test, ANOVA, the Scheffé test, Pearson's correlation coefficients, and multiple regression analysis using the SPSS/WIN 25.0 program. Results : Nursing performance of the participants was positively correlated with communication ability (r=.64, p<.001), job satisfaction (r=.26, p<.001), and organization commitment (r=.29, p<.001). Factors significantly influencing the participants' nursing performance included academic background (𝛽=.16, p=.032) and communication ability (𝛽=.50, p<.001). The explanatory power of these variables for nursing performance was recorded at 49.9% (F=19.04, p<.001). Conclusion : The use of various programs in the hospital and the development of effective communication ability with medical staff and other departments among nurses will help improve nursing performance, cooperation with other departments, and patient care.