• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4188-4206
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• 2016

Power control is widely used to reduce co-channel interference in wireless networks and guarantee the signal-to-interference plus noise ratio (SINR) of ongoing connections. This technique is also effective for wireless body area networks (WBANs). Although achieving satisfactory SINR is important for WBAN users, they may not be willing to achieve it at arbitrarily high power levels since power is a scarce resource in WBANs. Besides, for WBANs with different purposes, the QoS requirements and concern about the power consumption may be different. This motivates us to formulate the power control problem using the concepts from microeconomics and game theory. In this paper, the QoS objective is viewed as a utility function, which represents the degree of user satisfaction, while the power consumption is viewed as a cost function. The power control problem consequently becomes a non-cooperative multiplayer game, in which each player tries to maximize its net utility, i.e., the utility minus the cost. Within this framework, we investigate the Nash equilibrium existence and uniqueness in the game and derive the best response solution to reach the Nash equilibrium. To obtain the optimal transmission power in a distributed way, we further propose a utility-based and QoS-aware power control algorithm (UQoS-PCA). Tunable cost coefficient in UQoS-PCA enables this scheme to be flexible to satisfy diverse service requirements. Simulation results show the convergence and effectiveness of the proposed scheme as well as improvements over existing algorithm.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.7
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• pp.2631-2649
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• 2021

Device-to-Device (D2D) communication is one of the enabling technologies for 5G networks that support proximity-based service (ProSe) for wireless network communications. This paper proposes a power control algorithm based on the Nash equilibrium and game theory to eliminate the interference between the cellular user device and D2D links. This leadsto reliable connectivity with minimal power consumption in wireless communication. The power control in D2D is modeled as a non-cooperative game. Each device is allowed to independently select and transmit its power to maximize (or minimize) user utility. The aim is to guide user devices to converge with the Nash equilibrium by establishing connectivity with network resources. The proposed algorithm with pricing factors is used for power consumption and reduces overall interference of D2Ds communication. The proposed algorithm is evaluated in terms of the energy efficiency of the average power consumption, the number of D2D communication, and the number of iterations. Besides, the algorithm has a relatively fast convergence with the Nash Equilibrium rate. It guarantees that the user devices can achieve their required Quality of Service (QoS) by adjusting the residual cost coefficient and residual energy factor. Simulation results show that the power control shows a significant reduction in power consumption that has been achieved by approximately 20% compared with algorithms in [11].

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.11
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• pp.5234-5251
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• 2018

It is well-known that virtualization technology can bring many benefits not only to users but also to service providers. From the view of system security and resource utility, higher resource sharing degree and higher system reliability can be obtained by the introduction of virtualization technology in distributed cloud. The small size time-sharing multiplexing technology which is based on virtual machine in distributed cloud platform can enhance the resource utilization effectively by server consolidation. In this paper, the concept of memory block and user satisfaction is redefined combined with user requirements. According to the unbalanced memory resource states and user preference requirements in multi-virtual machine environments, a model of proper memory resource allocation is proposed combined with memory block and user satisfaction, and at the same time a memory optimization allocation algorithm is proposed which is based on virtual memory block, makespan and user satisfaction under the premise of an orderly physical nodes states also. In the algorithm, a memory optimal problem can be transformed into a resource workload balance problem. All the virtual machine tasks are simulated in Cloudsim platform. And the experimental results show that the problem of virtual machine memory resource allocation can be solved flexibly and efficiently.

• International Journal of Contents
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• v.5 no.3
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• pp.14-18
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• 2009

Traditional methods and materials used for Korean buildings need to be well organized and managed so that they can be utilized in modernization of old buildings. Supporting web-based management of information of Korean traditional building materials helps spread the related knowledge. This paper identifies the characteristics of traditional building materials data, and develops an information structure to represent the related information effectively. It also describes design decisions on web-based user interfaces to support flexible browsing and retrieval of the managed data. As the traditional building data are described by old domain-specific technical terms, utility of the developed service might be limited to those who are familiar with the terms. As an approach to tackle this problem, the proposed system supports user tagging by allowing users to classify the stored information using their own terms, and also to retrieve data using the user-supplied tags.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.6
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• pp.287-298
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• 2000

The UCA is a standard-based approach to utility communications which provides for wide scale integration of functional areas including customer interface, distribution, transmission, power plant, control center, and corporate information systems. Field devices in the power facilities require real-time communications, and they must be interconnected into fieldbus. This study introduces a method of implementing gateway that interfaces UCA and fieldbus. In this study, PROFIBUS and FOUNDATION Fieldbus are selected as candidate fieldbus protocols. Protocol interface in the gateway can be accomplished by mapping objects and services of UCA and fieldbus. MOst of the UCAs CASM objects and services are directly mapped into those of the application and user layers of fieldbus. However, some CASM services are not supported in the application and user layers of fieldbus. This study presents the method of implementing those services. In order to show that the implementation of interface is possible, this study presents pseudo-codes of interface program that maps the objects and services of UCA and fieldbus.

• ETRI Journal
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• v.34 no.3
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• pp.341-351
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• 2012

We deal with a resource allocation problem for multimedia service discrimination in wireless networks. We assume that a service provider allocates network resources to users who can choose and access one of the discriminated services. To express the rational service selection of users, the utility function of users is devised to reflect both service quality and cost. Regarding the utility function of a service provider, total profit and efficiency of resource usage have been considered. The proposed service discrimination framework is composed of two game models. An outer model is a repeated Stackelberg game between a service provider and a user group, while an inner model is a service selection game among users, which is solved by adopting the Kalai-Smorodinsky bargaining solution. Through simulation experiments, we compare the proposed framework with existing resource allocation methods according to user cost sensitivity. The proposed framework performed better than existing frameworks in terms of total profit and fairness.

• Journal of Families and Better Life
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• v.17 no.2
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• pp.1-18
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• 1999

The purpose of this study was to evaluate the utility of the community welfare center. for the purpose this study consisted of three main subjects(1) A analysis about the programs of the community welfare center (2) A analysis about the experience of the user and non-user on the community welfare center (3) A analysis about the demand for family welfare service program For the data set 398 married women living in Jeonju were chosen. The data were analyzed with the spss pc+ program. The major findings were as follows : (1) The program of community welfare center consisted of child adolescent elder family a disabled person community welfare program Among contents of this program family welfare program is limited to level of individual needs (2) The wives experienced of community welfare center did not satisfied about equipment location program of community welfare program The 44.0 portion of wives not experience of community wlfare center have no plan using of community welfare center (3) The wives hoped to establish diversed subjects such as parents-child communication conjugal communication sexuality education for child child care techniques health and nutrition of family member time managememt and lesuire and consumer's rights and damage relief.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.855-861
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• 2005

Every public agency governing infrastructure has to plan effectively for rehabilitation of existing facilities within the constraints of the capital program. Numerous technical, social, political, financial, and management constraints govern the decision to rehabilitate a facility. However, without a systematic procedure for selecting facilities for rehabilitation, within the prevailing constraints, it is possible that the funds available for rehabilitation might be suboptimized. Therefore, a decision support system that assists the user in selecting facilities for rehabilitation while considering the technical, social, financial, and political and management constraints will be useful in the decision-making process. This paper compares the Analytical Hierarchy Process (AHP) with the Swing Weight method used to prioritize functional criteria for suburban station rehabilitation. This paper also contains a brief discussion about the relevance of the Multi Attribute utility theory in developing a decision model for the problem at hand. The results of this paper provides the user with a decision support system that would prioritize the stations in order of their weights obtained by a systematic evaluation of various criteria and sub-criteria involved in the decision making process

• The Journal of Information Systems
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• v.13 no.1
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• pp.97-119
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• 2004

Recently, many e-business companies started to charge fees to the use of information contents service. However, little is known about how users evaluate and determine to purchase information services. Past technology adoption research has focused primarily on the positive utility gains side, focusing on usefulness and ease of use. Purchase of e-service, however, involves not only the position utilities but also negative utilities. This research uses the service value model(SVM) and explains user's intention of purchasing a new information service. Based on the Perceived Value Framework, this research investigates the impacts of the service quality and the fee charge on the user's perceived service value and further on user's intention of adopting the e-service. One of the most important postulations of this research is that both service quality and the fee charge influence user's intention through affecting the user's perceived service value. This research presences a conceptual model of users' e-service evaluation process. The conceptual framework provides a basis for understanding how perceptions of quality and sacrifice influence value perceptions and purchase intentions. The results of an empirical research suggest that the both service quality and fee charge have influences on the perceived service value. However, they do not directly affect user's intention to purchase the e-service. They affect user's intention to purchase through affecting the perceived service value. In conclusion, this research provides a base to build on for other research studying use intention model of new e-service.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.2
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• pp.61-68
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• 2010

As a result of the growth of mobile devices such as PDA and cellular phone, a user can utilize various digital contents everywhere and anytime. However, mobile devices have the limited resources and interaction mechanisms. This paper introduces the schema for a user activity estimation and its application in order to overcome the poor user interface and limited resource problems. We are able to supplement lacking the user interface of mobile devices by using the user activity estimation proposed in this paper, and its application is a intelligent control interface for the display power on or off which can effectively utility the battery of the mobile device.