• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.4
• /
• pp.1820-1840
• /
• 2017

Aiming at the phenomenon of false information issued by service providers in cloud computing environment, a method for service evaluation based on fuzzy theory is put forward in this paper. According to the quality of services provided by cloud service providers and their behavior during interactions, a trust relationship between cloud service providers and cloud service consumers is established, which can be quantified by using fuzzy theory. The quality of services is evaluated by drawing on the trust relationship. In our method, the recommendation credibility of a cloud service consumer is determined through behavior similarity with evaluators and a praise factor. The introduction of the praise factor better suits the phenomenon of a high-quality service getting more repeat customers. The negative impact of dishonest customers is reduced, and the accuracy of trust and cloud service quality evaluation is improved by introducing a confidence factor that can be dynamically adjusted. The experimental results show that our method can effectively and accurately evaluate the trust value and service quality of providers, while weakening the influence of dishonest consumers, and quickly detect dishonest service providers. This is beneficial for consumers trying to find high quality service providers for similar services.

• Journal of Information Technology Applications and Management
• /
• v.17 no.3
• /
• pp.83-97
• /
• 2010

The purpose of this study is to examine the impacts of media symbol variety on group performance in virtual teams. Symbol variety is defined as the number of ways in which information can be communicated and includes Daft and Lengel [1986]'s multiplicity of cues and language variety. According to media richness theory and media synchronicity theory, the use of media with high symbol variety is assumed to facilitate and promote communications among virtual team members. Therefore, it is expected that the media symbol variety is positively associated with group performance in virtual teams. Furthermore, online relationship building is expected to mediate the impacts of symbol variety on the performance. To confirm the suppositions, a controlled lab experiment was conducted with 60 undergraduate students as subjects. In the experimental virtual teams, subjects were allowed to communicate with other members using text-based messenger with emoticons. Subjects in the control virtual teams were allowed to communicate using only text-based messenger. The direct impact of symbol variety on group performance in virtual teams was found insignificant. However, the online relationship was found to completely mediate the positive impact of symbol variety on group performance. The implications and limitations of this study are also discussed for future research.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.12 no.1
• /
• pp.107-117
• /
• 2016

This study investigates design strategies for improving the educational quality of multimedia contents for early childhood education. It emphasizes both traditional education theory and developmental aspects in its exploration of interactive and educational qualitative multimedia contents for early children. Accordingly, for an effective early childhood education, it is necessary to experience of the playful learning for the conception of ideas and the understanding of the social life. Because this study 1) possibility of multimedia contents for early childhood education, 2) computer application method for early childhood education, 3) examines used in the designing of multimedia contents for early childhood education according to traditional education theory. Multimedia early childhood education system is possible to organize information such as test, image, sound and video based on hyperlink system. I use Microsoft's Ms-office and Asymetrix's ToolBook software that are useful for hyperlink and parameter. Multimedia contents and other pages are used by Dynamic Data Exchange(DDE). Therefore multimedia contents for early childhood education is a useful tool for students of early childhood education department, parents, and children.

• Journal of the Korean Society for Library and Information Science
• /
• v.21
• /
• pp.249-290
• /
• 1991

Theoretical developments in the information retrieval have offered a number of alternatives to traditional Boolean retrieval. Probability theory and fuzzy set theory have played prominent roles here. Fuzzy set theory is an attempt to generalize traditional set theory by permitting partial membership in a set and this means recognizing different degrees to which a document can match a request. In this study, an experimentation of a document retrieval system using the fuzzy relation matrix of the keywords is described and the results are offered. The queries composed of keywords and Boolean operaters AND, OR, NOT were processed in the retrieval method, and the method was implemented on the PC of 32bit level (30 MHz) in an experimental system. The measurement of the recall ratio and precision ratio verified the effectiveness of the proposed fuzzy relation matrix of keywords and retrieval method. Compared to traditional crisp method in the same document database, the recall ratio increased $10\%$ high although the precision ratio decreased slightly. The problems, in this experiment, to be resolved are first, the design of the automatic data input and fuzzy indexing modules, through which the system . can have the ability of competition and usefulness. Second, devising a systematic procedure for assigning fuzzy weights to keywords in documents and in queries.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.5
• /
• pp.2732-2753
• /
• 2019

With the application of wireless sensor networks in the fields of ecological observation, defense military, architecture and urban management etc., the security problem is becoming more and more serious. Characteristics and constraint conditions of wireless sensor networks such as computing power, storage space and battery have brought huge challenges to protection research. Inspired by the danger theory in biological immune system, this paper proposes an intrusion detection model for wireless sensor networks. The model abstracts expressions of antigens and antibodies in wireless sensor networks, defines meanings and functions of danger signals and danger areas, and expounds the process of intrusion detection based on the danger theory. The model realizes the distributed deployment, and there is no need to arrange an instance at each sensor node. In addition, sensor nodes trigger danger signals according to their own environmental information, and do not need to communicate with other nodes, which saves resources. When danger is perceived, the model acquires the global knowledge through node cooperation, and can perform more accurate real-time intrusion detection. In this paper, the performance of the model is analyzed including complexity and efficiency, and experimental results show that the model has good detection performance and reduces energy consumption.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.18 no.8
• /
• pp.2119-2136
• /
• 2024

The rapid progress of social media allows more people to express their feelings and opinions online. Many data on social media contains people's emotional information, which can be used for people's psychological analysis and emotional calculation. This research is based on the simplified psychological scale algorithm of multi-theory integration. It aims to accurately analyze people's psychological emotion. According to the comparative analysis of algorithm performance, the results show that the highest recall rate of the algorithm in this study is 95%, while the highest recall rate of the item response theory algorithm and the social network analysis algorithm is 68% and 87%. The acceleration ratio and data volume of the research algorithm are analyzed. The results show that when 400,000 data are calculated in the Hadoop cluster and there are 8 nodes, the maximum acceleration ratio is 40%. When the data volume is 8GB, the maximum scale ratio of 8 nodes is 43%. Finally, we carried out an empirical analysis on the model that compute the population's psychological and emotional conditions. During the analysis, the psychological simplification scale algorithm was adopted and multiple theories were taken into account. Then, we collected negative comments and expressions about Japan's discharge of radioactive water in microblog and compared them with the trend derived by the model. The results were consistent. Therefore, this research model has achieved good results in the emotion classification of microblog comments.

• Journal of the Korean housing association
• /
• v.22 no.3
• /
• pp.73-82
• /
• 2011

The purpose of this study was to develop the curriculum of spatial convergence studies for the major field of housing and interior design. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities which were 20 colleges the major field of housing and interior design and 160 colleges of architectural design, and public institutions the MLTM and the KRIHS. The major results of this study were as follows. 1) Government has been supported the specialized graduate school of spatial information and the university which they have spatial information curriculum during 5 years. 2) The department of spatial information has been educated the theory and practice about spatial issues in order to train the spatial specialist helpful to the new growing industry. 3) There were little changed curriculum which has related to the department of housing and interior design. The half of their curriculum were housing project and interior design. The spatial convergence studies educational program should be grow up step by step. The first is basic level to learn the basic theory of spatial studies for example the spatial introduction or the housing and the second is low level to learn the depth theory of spatial studies for example the design I or the housing development. The third is middle level to apply the depth theory of spatial studies for examples the design II, III or housing policy and institutions. And the last is high level to practice the depth theory of spatial studies for example housing construction or internship.

• ETRI Journal
• /
• v.37 no.3
• /
• pp.450-459
• /
• 2015

Small cell networks, as an important evolution path for next-generation cellular networks, have drawn much attention. Different from the traditional base stations (BSs) always-on model, we proposed a BSs on-off model, where a new, simple expression for the probabilities of active BSs in a heterogeneous network is derived. This model is more suitable for application in practical networks. Based on this, we develop an analytical framework for the performance evaluation of small cell networks, adopting stochastic geometry theory. We derive the system coverage probability; average energy efficiency (AEE) and average uplink power consumption (AUPC) for different association strategies; maximum biased received power (MaBRP); and minimum association distance (MiAD). It is analytically shown that MaBRP is beneficial for coverage but will have some loss in energy saving. On the contrary, MiAD is not advocated from the point of coverage but is more energy efficient. The simulation results show that the use of range expansion in MaBRP helps to save energy but that this is not so in MiAD. Furthermore, we can achieve an optimal AEE by establishing an appropriate density of small cells.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.9
• /
• pp.3827-3833
• /
• 2011

This paper performed empirical tests of the validity of the pecking order theory which explains financing behavior of firms under information asymmetry. The results of regression analyses using the data of listed manufacturing companies in the Korean Stock Market from 1981 to 2010 have shown strong evidences supporting the pecking order theory. Especially regression coefficients of change of debt on funds deficit and control variables were found to be almost (+1) with statistically significance, which is interpreted as being consistent with the pecking order theory. Same results were found when I performed regression analyses by dividing the sample period into pre-currency crisis period, currency crisis period and post-currency crisis period and using 2 regression models. Change of tangible asset were found to function as collateral rather than reducing information asymmetry and as the firm size decreased, use of debt increased and as profitability increased use of debt decreased, which are consistent with the pecking order theory.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.26 no.4
• /
• pp.179-200
• /
• 2015

The purpose of this study is to examine research trends on theory use in Korean LIS, and ultimately to identify its academic growth and change. This study conducted content analysis, with a sample of 344 articles in Journal of the Korean Society for Library and Information Science during the past five years from 2010 to 2014. Then longitudinal analysis was additionally carried out by comparing with a data set from 1984 to 2003. Findings are as follows. 13.7% of research articles used theories on average 2.02 times. The most theories were deployed at the level of Spot Citing and the next most theories were at the level of Theory Application. Research on the subject of education and information use/seeking used theories most frequently. Theories from LIS were 31.9% and those from social science were 58.3% of all. Also, longitudinal analysis results support the conclusion that there was no quantitative increase but was clear qualitative growth in theoretical research of LIS. And the current theoretical framework of LIS research has closer relationships with pedagogy and psychology among social science disciplines than in the past.