• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.2
• /
• pp.547-566
• /
• 2014

This study investigates the decisive factors affecting the survival or collapse of cable networks in the Korean paid broadcasting market from 1993 to 2010. The effects of performance variables discussed in previous studies were verified through survival analyses. According to the results, the most influential factors in the survival of cable networks were horizontal integration (MPP), channel genre, the scheduling of HDTV content, and the proportion of access program scheduling. These findings imply that the differentiation strategy of content suppliers is the most decisive factor among all business performance-related factors. Specifically, the content supply power and strategy of the program provider (PP) have the greatest influence on cable network viability. The present study is meaningful as the first attempt to establish the performance of PPs in Korean pay broadcasting markets through the viewpoint of organizational mortality. Accordingly, the present study can supplement the results of cross-sectional studies conducted with smaller samples.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.9
• /
• pp.3823-3840
• /
• 2020

Recently, auto-encoder has emerged as the most popular method in convolutional neural network (CNN) based image compression and has achieved impressive performance. In the traditional auto-encoder based image compression model, the encoder simply sends the features of last layer to the decoder, which cannot allocate bits over different spatial regions in an efficient way. Besides, these methods do not fully exploit the contextual information under different receptive fields for better reconstruction performance. In this paper, to solve these issues, a novel auto-encoder model is designed for image compression, which can effectively transmit the hierarchical features of the encoder to the decoder. Specifically, we first propose an adaptive bit-allocation strategy, which can adaptively select an importance channel. Then, we conduct the multiply operation on the generated importance mask and the features of the last layer in our proposed encoder to achieve efficient bit allocation. Moreover, we present an additional novel perceptual loss function for more accurate image details. Extensive experiments demonstrated that the proposed model can achieve significant superiority compared with JPEG and JPEG2000 both in both subjective and objective quality. Besides, our model shows better performance than the state-of-the-art convolutional neural network (CNN)-based image compression methods in terms of PSNR.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.2
• /
• pp.514-537
• /
• 2020

Wireless sensor network (WSN) is a distributed network composed of many sensory nodes. It is precisely due to the clustering unevenness and cluster head election randomness that the energy consumption of WSN is excessive. Therefore, a many-objective optimization WSN energy balance model is proposed for the first time in the clustering stage of LEACH protocol. The four objective is considered that the cluster distance, the sink node distance, the overall energy consumption of the network and the network energy consumption balance to select the cluster head, which to better balance the energy consumption of the WSN network and extend the network lifetime. A many-objective optimization algorithm to optimize the model (LEACH-ABF) is designed, which combines adaptive balanced function strategy with penalty-based boundary selection intersection strategy to optimize the clustering method of LEACH. The experimental results show that LEACH-ABF can balance network energy consumption effectively and extend the network lifetime when compared with other algorithms.

• Proceedings of the Korea Contents Association Conference
• /
• 2006.11a
• /
• pp.100-105
• /
• 2006

We are faced with the age of limitless competition because knowledge and information are the most important to nation's competition and we should struggle to obtain them. Our county made some programmes such as next growth engine and 21c frontier R&D to prepare future. But, the responsible organizations which drive the programmes sponsored by government had a limitation in point of obtaining exact information quickly. So, in this report, we explain the strategy of getting the future leading technology based on internet.

• Journal of Internet Computing and Services
• /
• v.10 no.3
• /
• pp.61-69
• /
• 2009

Most existing clustering protocols have been aimed to provide balancing the residual energy of each node and maximizing life-time of wireless sensor networks. In this paper, we present the threshold based cluster head replacement strategy for clustering protocols in wireless sensor networks. This protocol minimizes the number of cluster head selection by preventing the cluster head replacement up to the threshold of residual energy. Reducing the amount of head selection and replacement cost, the life-time of the entire networks can be extended compared with the existing clustering protocols. Our simulation results show that our protocol outperformed than LEACH in terms of balancing energy consumption and network life-time.

• Journal of Internet Computing and Services
• /
• v.21 no.3
• /
• pp.61-70
• /
• 2020

The 4th Industrial Revolution is a revolutionary change through intelligence, big fusion and personalization, and the importance of sensor technology that is the basis of core technology is emerging. This study empirically analyzes the derivation of national strategy for R&D of sensor technology, and draws out the effect of technology internalization effort through strategic R&D activities on technical performance and further on national economy. The research and development results are calculated for each type of technology internalization, and the results of the research and development are verified to establish a structure that contributes to the national economic performance. As a national technology internalization strategy, considering its own R&D investment and joint research and development, we examine the impact of each factor on patents and GDP, focusing on causality and ripple effects. For causality analysis, Grandeur causality analysis shows that R&D investment and joint research and development in all countries have mutual causal relationship with GDP. The implications are as follows. First, it is necessary to establish the policy of national economic development through the internalization of technology and knowledge. Second, it is necessary to establish policies according to the type of knowledge internalization. Third, it will be necessary to create an ecosystem environment based on a virtuous relationship between knowledge internalization and national technology and economic development.

• Journal of Korea Multimedia Society
• /
• v.3 no.3
• /
• pp.320-332
• /
• 2000

Web consists of the grand virtual system which is made of all connected computers network. We can solve the huge problem which requires high quality in cost performance and powerful computing power to use a numerous idle state system on internet as process it parallel. However, we have to consider heterogeneous computing resources, accessibility, and reliability to carry out parallel system on global environment, not network but whole Internet. In this paper, We the WebImg system which has the power of web computing, and show the flexible task allocation strategy in heterogeneous hosts. Also, we evaluate its performance, moreover the proposed task allocation strategy supplies fault tolerance by controlling host situation at any time.

• Journal of Satellite, Information and Communications
• /
• v.12 no.4
• /
• pp.146-151
• /
• 2017

This paper proposes a transmission algorithm that optimizes transmission power and sub-channel allocation to maximize energy efficiency considering characteristics of the channel impedance of power lines in power line communication systems. Since the received power at the receiver is influenced by the characteristics of the power line channel, it is necessary to consider channel characteristics when developing a transmission strategy in a power line communication systems. In addition, the energy efficiency should be optimized while meeting the practical constraints, such as the maximum transmission power limit of the transmitter and minimum quality of service for each user. In the computer simulation, we confirm that the energy efficiency of the proposed algorithm is improved compared to baseline schemes.

• Journal of Fashion Business
• /
• v.21 no.1
• /
• pp.124-133
• /
• 2017

This study analyzed consumers' online fashion shopping site usage by site type and analyzed how product information search and product purchase differ. In addition, by comparing and analyzing preference and selection factors of PC and mobile shopping, we tried to provide basic data of effective mobile commerce operation strategy according to expansion of mobile market in fashion industry. We surveyed the use of 6 types of online sites (portal site, open market, general shopping mall, social commerce shopping mall, brand shopping mall and non-brand shopping mall) to understand the usage of mobile shopping site for consumers' fashion products. Consumer survey subjects were 373 college students in their early 20s who had the most mobile shopping experiences. The questionnaire consisted of online fashion site usage items, internet and mobile fashion shopping preference (6 items), internet and mobile shopping choice behavior (10 items), and purchase intention (3 items) .Data were analyzed using SPSS 14.0 program. The high preference of portal sites, open market, social commerce, and non-brand shopping malls in shopping online fashion products is a result of the perceptual changes of major distribution channels and the trends of consumers' value consumption tendency. Therefore, it is necessary for fashion companies to actively cope with fashion product distribution competition with huge shopping sites of current online market by well understanding consumers' preference trends and factors of online sites.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.4
• /
• pp.2020-2037
• /
• 2017

In order to improve the energy efficiency of n-Epidemic routing protocol in opportunistic networks, in which a stable end-to-end forwarding path usually does not exist, a novel adjustment strategy for parameter n is proposed using learning atuomata principle. First, nodes dynamically update the average energy level of current environment while moving around. Second, nodes with lower energy level relative to their neighbors take larger n avoiding energy consumption during message replications and vice versa. Third, nodes will only replicate messages to their neighbors when the number of neighbors reaches or exceeds the threshold n. Thus the number of message transmissions is reduced and energy is conserved accordingly. The simulation results show that, n-Epidemic routing protocol with the proposed adjustment method can efficiently reduce and balance energy consumption. Furthermore, the key metric of delivery ratio is improved compared with the original n-Epidemic routing protocol. Obviously the proposed scheme prolongs the network life time because of the equilibrium of energy consumption among nodes.