• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.8
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• pp.1765-1772
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• 2015

In the underwater acoustic communication channels, multipath reflection become the cause of obstacle. Generally, equalizer has been applied to overcome these problems. In this paper, the method was proposed to optimize tap-length of decision feedback equalizer using genetic algorithm. After inputting feed-forward filter length and feed-back filter length as genetic information of the genetic algorithm, it optimize tap-length using BER(bit error rate) calculation in accordance with object function. The object function consist of decision feedback equalizer and BER calculation. For the purpose of BER calculation in the object function, the method was proposed to optimize the tap-length of decision feedback equalizer with genetic algorithm using preamble signals. As a result of experiments, the optimized BER is 0.0355 for signals which were received through a 25m receiver and which were applied to calculate BER merely using preamble signals in object function. When all data were used to calculate BER in object function, the optimized BER is 0.0215.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.2 no.1
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• pp.14-19
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• 1977

Our social needs many kinds of different circulation method, so the function of communication has been changed the whole situation through the process of many transitions. The form of our civilization is changing into the social which is full of information owing to the development of mass communication. The value of using the information is murk heightening by it's own high dependence. The using of information is being rapidly enlarged, at the same time the development of technique on the information management is caused by the development of communication technique. Thus geometrical operation of both of the above has changed the function of communication. Maybe we will have to present all the primary factors on the communication transition from the social side in order to develop communication method.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.634-640
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• 2015

This paper deals with the design of a microstrip line feed toppled T shaped microstrip patch antenna that gives dualband characteristics at 4 GHz and 6.73 GHz respectively. The simulation of proposed antenna geometry has been performed using method of moment based IE3D simulation software. A radial basis function neural network (RBFNN) is used for the estimation of bandwidth for dualband at 4 GHz and 6.73 GHz respectively. In RBFNN model, antenna parameters such as dielectric constant, height of substrate, and width are used as input and bandwidth of first and second band is considered as output of the network. To validate the RBFNN output, an antenna has been physically fabricated on glass epoxy substrate. The fabricated antenna can be utilized in S and C bands applications. RBFNN results are found in close agreement with simulated and experimental results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.13 no.5
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• pp.379-389
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• 1988

In this paper, an algorithm for obtaining 2-state switching failure function and a terminal pair reliability evaluation method in a communication network are proposed. The communication network is modeled by a graph. By using the sequence of matrix transformations for the graph, minimal cut-set matrix representing all minimal cut-sets which completely interrupt the communication path is determined and 2-state switching failure function is then obtained from the minimal cut-set matrix. The terminal pari reliability of the communication network is evaluated by corresponding the random variables to 2-state switching failure function. Illustrative examples are provided to demonstrate the algorithm. A computer program evaluating the terminal pair reliability in a complex and large network has also been developed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.7
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• pp.559-565
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• 2014

In this paper, we propose an unambiguous correlation function for time-multiplexed binary offset carrier (TMBOC) signal tracking. Specifically, considering that the TMBOC modulation transmits two kinds of sine-phased BOC signals in time domain alternatively, we generate sub-correlation functions for each of the BOC signals by using split sine-phased BOC signals, and then, obtain a correlation function with no side-peak by recombining the sub-correlation functions. From numerical results, we confirm that the proposed correlation function offers an improved tracking error standard deviation performance than the TMBOC autocorrelation function.

• Journal of Electrical Engineering and information Science
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• v.1 no.1
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• pp.164-172
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• 1996

The partitioning of related objects should be performed before clustering for an efficient access in object-oriented databases. In this paper, a horizontal partition of related objects in object-oriented databases is presented. All subclass nodes in a class inheritance hierarchy of a schema graph are shrunk to a class node in the graph that is called condensed schema graph because the aggregation hierarchy has more influence on the partition than the class inheritance hierarchy. A set function and an accessibility function are defined to find a maximal subset of related objects among the set of objects in a class. A set function maps a subset of the domain class objects to a subset of the range class objects. An accessibility function maps a subset of the objects of a class into a subset of the objects of the same class through a composition of set functions. The algorithm derived in this paper is to find the related objects of a condensed schema graph using accessibility functions and set functions. The existence of a maximal subset of the related objects in a class is proved to show the validity of the partition algorithm using the accessibility function.

• Journal of the Korea Society of Computer and Information
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• v.10 no.6 s.38
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• pp.309-320
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• 2005

The harm caused by the opposite function of information and communication has also done increasing with making use of internet more spread. Especially the information and communication are even used as new criminal methods in the society. The objective of this study is to find the orientation on the ethics education of information and communication through the opinion of the undergraduate students who lead the culture of internet for suggestion of the target to raise the upright and sound members of society as well as to solve the above such problems and to establish the desirable model of the ethics. From the questionnaire result by the undergraduate students of S University, students in the field of Humanities and Social Science need the education against the opposite function of information and communication and also the education of netiquette of conscience and moral. In case of opinions in the field of Science and Engineering, the result shows that the students have the opinion on the necessity of the professional education to deal with the opposite function to information and communication as well as the education for upgrade of ability to make use of expert knowledge of information and communication toward the positive side. Finally, the students in the field of Medicine show that they have also the opinion to deal with the opposite function of information and communication. In addition, such result shows that they have the opinion of necessity to the special education against various addicted symptom related to the computer.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.05a
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• pp.95-96
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• 2007

Language is the method for communication. Semantician, G. Leech categorized the function of language as informational, expressive, directive, aesthetic and phatic one. Therefore, language can be defined as the social symbol system and the media for communication. Space, also, performs the role of symbol, information and communication. Space can be the media for the communication and the design can be logical construction process by it's arbitrary interpretation. The researcher considered the common points between verbal language and visual language as the tools for the mutual communication, tried to transit them into the 'space' as object language after analyzing 'image of poetry' as meta language, so that the old perspective of space design as function can be renewed as information system of the significant meaning delivery in the context of language's multiplicity, expandibility and changeability.

• The Transactions of the Korea Information Processing Society
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• v.7 no.5
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• pp.1553-1558
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• 2000

The development of recent computer and communication technology has changed Automation System using communication network, and the new USB substituted with Serial Communication is already developed and now popular. In this paper, High speed data transfer system design using USB interface and communication application simulated for the situation is introduced. Base on USB, we can use additive function efficiently coped with former field device. The 'Winsock Connection USB Ternimal,' designed for hardware simulation, control the field device connected by USB, and provide the way for remote control of field device by Telnet connection through TCP/IP. That theorem can guarantee controlling direct input dta of user, and acuate function of field device using USB Packet Transmission. As a result of amy research, this communication application system identified good operation of field device with those of former field device. Another result of the experiment of hardware operation, we obtained accomplishment that the sufficient bandwidth guarantee of USB has high speed and high performance, and reduce the occupancy of system.

• Journal of Applied Reliability
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• v.8 no.4
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• pp.181-192
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• 2008

In this paper, we proposed effective algorithm that do Availability of communication network account using total probability formula. Use path tracing method about PSTN linked with MSC in WCDMA considering occasion that do not consider mobility of terminal and Availability did account. First, express minimum path series gathering by structure function after network that do modeling by stochastic graph for communication network saves all minimal path sets between particular two abutments and we gain Availability value in angular variable after express structure function by Boolean operation form and Availability between two abutments did account.