• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.3771-3788
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• 2015

This paper studies the distributed energy efficient resource management in the Internet of Things (IoT). Wireless communication networks support the IoT without limitation of distance and location, which significantly impels its development. We study the communication channel and energy management in the wireless communication network supported IoT to improve the ability of connection, communication, share and collaboration, by using the game theory and distributed learning algorithm. First, we formulate an energy efficient neighbor collaborative game model and prove that the proposed game is an exact potential game. Second, we design a distributed energy efficient channel selection learning algorithm to obtain the global optimum in a distributed manner. We prove that the proposed algorithm will asymptotically converge to the global optimum with geometric speed. Finally, we make the simulations to verify the theoretic analysis and the performance of proposed algorithm.

• Informatization Policy
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• v.17 no.1
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• pp.3-22
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• 2010

This study reviewed and ascertained policy researches relating to the Internet in the field of communication. With using a meta-analysis, this study attempts to classify 44 academic papers from 2000 to 2009 by research theme, methodology, theoretic rationale, related sub-theme, and targeted service and area. It is found that the themes of preceding researches examined herein were limited to the 4th domain in Developmental Model of Media Research. Such researches mainly relied on exploratory studies and only a few of them addressed theoretic rationales. Also, most of Internet regulation discussions focused on content regulation and general internet service. Lastly, researchers discussed laws having bearing on the Internet and social-cultural issues of the Internet.

• Journal of electromagnetic engineering and science
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• v.6 no.1
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• pp.10-17
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• 2006

For the sake of the potential ability of overcoming interference in TD-SCDMA(time division-synchronous code division multiple access) systems, pilot signal is adopted, but the presented TD-SCDMA protocol has not considered the Rake technique for their mobile terminals. This paper developed a RAKE receiver algorithm and an implementation circuit, which make use of the pilot signal in the burst structure of the TD-SCDMA base station to estimate main channel parameter(channel delays) in the downlink of TD-SCDMA wireless network. The algorithm can reduce multipath interference for the mobile units in multiusers' case. Theoretic performance analysis presented in the paper and computer simulations show that there is a range of BER for Rake receiver and confirm that the proposed RAKE receiver algorithm achieved a better performance under multipath fading propagation and multiusers conditions.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.862-864
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• 2003

Thresholding is a popular image segmentation method that converts a gray-level image into a binary image. The selection of optimum threshold has remained a challenge over decades. Many image segmentation techniques are developed using information about image in other space rather than the image space itself. Most of the technique based on histogram analysis information-theoretic approaches. In this paper, the criterion function for finding optimal threshold is developed using an intensity-based classuncertainty (a histogram-based property of an image) and region-homogeneity (an image morphology-based property). The theory of the optimum thresholding method is based on postulates that objects manifest themselves with fuzzy boundaries in any digital image acquired by an imaging device. The performance of the proposed method is illustrated on experimental data obtained by W-band millimeter-wave radiometer image under different noise level.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.185-195
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• 2012

The purpose of this paper is to analyze how strategically the bilaterally monopolistic firms, only-one-seller and only-one-buyer, behave in a situation in which each firm has uncertain information on its opponent firm's cost. Even though the two firms know that seeking integrated profit leads to the optimized profit for both firms, each firm has an incentive to opportunistically behave to increase its share of the integrated profit. These opportunistic behaviors of the firms are analyzed through a game theoretic approach especially finding Nash equilibrium mixed strategies for the strategic profiles such as true-report or not and monitoring or not. The comparative statics to the Nash equilibrium mixed strategies shows that as the profit share increases the probability of monitoring an opponent firm is decreased while the probability increases as the size of the overstated production cost increases. This study also shows that high penalty and low monitoring cost lead to high probability to tell the truth of the production cost.

• Journal of the Korea Society of Computer and Information
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• v.23 no.1
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• pp.131-137
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• 2018

This study conducted empirical analysis on the influence of perception of organization politics of social welfare facility employee to job attitude, and based on the analysis result, it aims to suggest theoretic and political implications. For this, the study conducted survey targeting social workers working at social welfare facilities in Gwangju. 350 copies of survey were distributed,. 197 copies were retrieved and 176 copies were used in analysis after excluding 21 copies with insincere reponses. The collected data was processed through SPSS 20.0 for reliability analysis, frequency analysis, T-test, and hierarchical regression analysis. The study results are as below. This study analyzed the job exhaustion, turn over intention and causal relationship as the result variables and perception of organization politics of social workers, and analyzed the leader trust as mediating effect among the previous researches related to perception of organization politics. As for the analysis result, the perception of organization politics of social workers improve job exhaustion and turn over intention, and leader trust was confirmed to have mediating effect on relationship among the variables.

• Journal of IKEEE
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• v.2 no.1 s.2
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• pp.24-33
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• 1998

Independent Component analysis (ICA) is a new statistical method for extracting statistically independent components from their linear instantaneous mixtures which are generated by an unknown linear generative model. The recognition model is learned in unsupervised manner so that the recovered signals by the recognition model become the possibly scaled estimates of original source signals. This paper addresses the neural learning approach to ICA. As recognition models a linear feedforward network and a linear feedback network are considered. Associated learning algorithms for both networks are derived from maximum likelihood and information-theoretic approaches, using natural Riemannian gradient [1]. Theoretical results are confirmed by extensive computer simulations.

• Journal of the military operations research society of Korea
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• v.24 no.1
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• pp.68-87
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• 1998

Techniques from decision analysis and expert system have both been extensively used in the development of computerized decision aids, although each discipline uses different approaches in knowledge (information or input) acquisition, representation, and problem solving methodology. From the perspective of many types of practical decision aiding applications, both normative decision aids and expert system technology have significant limitations. Many research efforts have been exerted toward complementing the one's deficiency with the other's possible techniques or vice versa. In this paper, among many possible complementary techniques for better decision aiding between decision analysis and expert system, we focus on the using prescriptive methodology of decision analysis which incorporates user's preference knowledge for conflict resolution in rule based expert system.

• Korean Journal of Remote Sensing
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• v.9 no.2
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• pp.21-34
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• 1993

Digitalized topographic information is necessary for many areas such as landscape analysis, civil engineering planning and design, and geographic information systems. It can also be used in flight simulator and automatic navigation of unmanned plane if it is stored in computer in relevant format. Topographic information is coded with various symbols including contour lines, and is analyzed by trained personnels. The information should be stored in computer for automatic analysis, but it requires a lot of time and manpower to enter the contours using manual input devices such as digitizing tablet. This paper deals with automatic extraction and reconstruction of 3D topographic information from 2D terrain map. Several algorithms were developed in this work including contour segment finding algorithm and contour segment linking algorithm. The algorithm were tested using real 2D terrain map.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.7
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• pp.575-597
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• 1991

As an elegant solution of the key management scheme for a conventional cryptosystem. Diffie and Hellman introduced a public key distrbution system, whose security depends on the intractabliity of discrete loganthm problem over a finite field, and since then a lot of vartants of DH KDSS have been proposed. In this paper, we present the systematic approach to analyzing the security of a generalized DH KDS and designing an efficient and secure scheme. We classify vanous attacking methods and point out a possible way to avoid these attacks through the examples of successful attacking methods and point out a possible way to avoid these attacks through the examples of successful attack against those systems proposed so far or designed for this purpose. As security analysis tools, we present the redueiblity test, the information theoretic approach, and the protocol analysis technique, which we apply to variations of DH scheme to examine their security under all possble attacks.