• Journal of Power Electronics
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• v.3 no.3
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• pp.145-150
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• 2003

Reliability, availability, and cost have been the major concerns for photovoltaic hybrid systems since their beginning as primary sources for much critical applications like communication units and repeaters. This paper descnbes the performance of two hybrid systems, photovoltaic-battery, wind-turbine coupled with the public-grid (PVBWG) hybrid system and photovoltaic-battery, wind-turbine coupled With the diesel generator (PVBWD) hybrid system The systems are sized to power a typical 300W/48V de telecommunication load continuously throughout the year Such hybrid systems consist of subsystems, which in turn consist of components Failure of anyone of these components may cause failure of the entire system. The reliability and availability basics, and estimation procedure for the two proposals are introduced also in this paper. The PVBWG and PVBWD system configurations are shown with the relevant mean-time-between-faIlure (MTBF) and failure rate (${\lambda}$) of each component. The characteristics equations of the two systems are deduced as a function of operating hours and the percentage of sun and wind availabilities per day. The system probability failure as well as the reliability is estimated based on the fault tree analysis technique. The results show that, by using standard or normal components MTBF, the PVBWG is more reliable and the time of periodic maintenance period is more than one year especially in the rich sites of both sun and wind, but PVBWD competes else Also, in the first five years from the system installation, the system is quit reliable and may not require any maintenance. The results show also, as the sun and wind are available, as the system reliable and available.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.2
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• pp.105-111
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• 1984

Recently, Hybrid Navigation Systems combining Omega, NNSS, Loran C and Dead reckoning etc. served to give us highly accurate ship's position, and a number of ships are equipped with these navigation systems. In order to evaluate for the accuracy of this navigation system observations of Loran C, 5970 and 9970 chains and Radar at the same time were made on board m.s Jeonbuk 401 and 403 training ships of Gunsan Fisheries Collage at nine stations in the yellow sea from July, 1982 to June, 1983, and then were done by the Hybrid Navigation System combining Dead reckoning and Loran C at the same areas. The authors investigated the accuracy of the Hybrid Navigation System based on measurements of the relative positional error which is defined as the difference between the position fixed by this system or the Loran C system, and the one by the Radar. The obtained results are as follows; 1. The mean standard deviation of the time difference of Loran C were about 0.21$\mu$s in 9970 chain and about 0.06$\mu$s in 5970 chain, and the fluctuation of the time difference of Loran C in 5970 chain was smaller than that in 9970 chain. 2. The positional error between two positions by Radar and the Hybrid Navigation System in 9970 chain was about 0.4 miles, and between two positions by Radar and Loran C was about 0.51 miles. The Hybrid Navigation System was therefore more accurate than Loran C System. 3. The positional error between two positions by Radar and Hybrid Navigation System in 5970 chain was about 0.4 miles, and between two positions by Radar and computer simulation of Loran C was about 0.98 miles. Consequently, Hybrid Navigation System was more accurate than computer simulation of Loran C system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.5
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• pp.448-456
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• 2007

Performance of PEM fuel cell systems and hybrid systems combining a PEMFC with a gas turbine have been evaluated. Two different reforming methods(steam reforming and autothermal reforming) were considered. Performances of fuel cell systems with two reforming methods were compared and effects of various design parameters on the system performance were investigated. Configurations of PEM fuel cell systems with two reforming methods have been revised to accommodate a gas turbine, resulting in PEMFC/GT hybrid systems. Performance of the hybrid systems were analyzed and compared with those of PEM systems. Influences of major design parameters on the hybrid system performance were also investigated.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2003.11a
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• pp.707-720
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• 2003

Product factory is a real-time financial product design system for the Internet customers. The hybrid product is a product taking combined characteristics of two different products. Hybrid product factory is a product factory that designs hybrid products from two different products based on both business rules and customer requirements. Though the importance of product factory is emphasized in the industry, there has not been much research peformed regarding product factory. In this research, we developed a product factory system that designs hybrid products. To design a hybrid product, it is necessary to have a method to combine attributes and values of two different products, and a method to control the combining operations to properly reflect business requirements. In this research, we developed four different combining operators and business rule representations. In addition, to prove the effectiveness of this methods, we implemented a prototypical system and demonstrated on cases regarding financial loan products.

• Journal of Computational Design and Engineering
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• v.2 no.3
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• pp.137-147
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• 2015

In this study, a new methodology in predicting a system output has been investigated by applying a data mining technique and a hybrid type II fuzzy system in CNC turning operations. The purpose was to generate a supplemental control function under the dynamic machining environment, where unforeseeable changes may occur frequently. Two different types of membership functions were developed for the fuzzy logic systems and also by combining the two types, a hybrid system was generated. Genetic algorithm was used for fuzzy adaptation in the control system. Fuzzy rules are automatically modified in the process of genetic algorithm training. The computational results showed that the hybrid system with a genetic adaptation generated a far better accuracy. The hybrid fuzzy system with genetic algorithm training demonstrated more effective prediction capability and a strong potential for the implementation into existing control functions.

• Journal of the Korean Society of Safety
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• v.32 no.6
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• pp.81-88
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• 2017

This study deals with the optimal design of a hybrid control system composed of a combination of active control system and passive control system for effective seismic performance improvement of two adjacent structures. The proposed hybrid control system adopts a configuration of installing an active control device in one building and connecting two adjacent structures with a passive control device so that the one-side active control force can be bi-directionally applied to both buildings through the passive connecting devices. In order to derive the optimal performance of the proposed system, the design parameters of the passive and active control systems were searched using the genetic algorithm. Numerical simulations of 10-story and 8-story buildings have been performed to verify the effectiveness of the proposed technique. For the purpose of comparison, the conventional independent control system with two identical active control systems being installed separately for each structure was also optimally designed and its seismic response has been evaluated as well. From the comparative results of the two control systems, it is demonstrated that the proposed hybrid control system requires larger control force for its one-side active control device than the conventional independent control system does for each of both-side active devices, but quite less than the total control force required for both-side devices of the independent control system, while maintaining similar seismic performance. Therefore, the proposed system is more economical and reliable than the conventional independent control system with two identical active devices.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.1
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• pp.25-37
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• 2019

Power-line communication (PLC) has influenced smart grid development. In addition, PLC has also been instrumental in current research on internet-of-things (IoT). Due to the implementation of PLC in smart grid and IoT environments, strides have been made in PLC and its combination with the wireless system to form a hybrid communication system. Also, PLC has evolved from a single-input-single-output (SISO) configuration to multiple-input-multiple-output (MIMO) configuration system, and from a point-to-point communication system to cooperative communication systems. In this work, we extend a MIMO wireless two-way amplify-and-forward (AF) cooperative communication system to a hybrid PLC and wireless (PLC/W) system configuration. We then maximize the weighted sum-rate for the hybrid PLC/W by optimizing the precoders at each node within the hybrid PLC/W system. The sum-rate problem was found to be non-convex, therefore, an iterative algorithm is used to find the optimal precoders that locally maximize the system sum-rate. For our simulation results, we compare our proposed hybrid PLC/W configuration to a PLC only and wireless only configuration at each node. Due to an improvement in system diversity, the hybrid PLC/W configuration outperformed the PLC only and wireless only system configurations in all simulation results presented in this paper.

• Journal of Microbiology
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• v.38 no.2
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• pp.113-116
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• 2000

Escherichia coli F plasmid partition apparatus is composed of two trans-acting proteins (SopA and SopB) and one cis-acting DNA sequence (sopC). The SopB-sopC complex has been suggested to serve a centromere-like function through its interaction with chromosomally encoded proteins which remain to be identified. In this paper, we are introducing a new yeast 1.5-hybrid system which assembles the two-hybrid and one-hybrid system as a mean to find and additional component of the F plasmid partition system, interacting with DNA (sopC)-bound SopB protein. The results indicates that this system is a promising one, capable of selecting an interacting component.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1795-1799
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• 2008

The heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a component of hnRNP complexes. This protein binds strongly to cytidine-rich RNA/DNA sequences. It is a nucleocytoplasmic shuttling protein. To investigate the functions of hnRNP K, I searched for hnRNP K-interacting proteins in HeLa cDNA library using a yeast two-hybrid screening system. One of the cDNA clones is identical to human hnRNP E1 (poly(rC) binding protein 1) cDNA (GenBank accession number XM_031585). In this study, hnRNP K is shown to specifically interact with hnRNP E1 in yeast two-hybrid system and in vitro biochemical assay.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.16-23
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• 2003

In this paper, we propose a new optical hybrid switching system that takes advantage of both Optical Burst Switching (OBS) and Optical Circuit Switching (OCS) technologies. This system classifies incoming IP traffic flows into short-lived and long-lived flows for hybrid switching. For performance analysis, we model the system as a single server queue in a Markovian environment. The burst generation process is assumed to follow a two-state Markov Modulated Poisson Process (MMPP), and the service rate fluctuates based on the number of concurrent OCS sessions. Results of the mean delay and queue size for OBS bursts are derived.