• The Journal of Society for e-Business Studies
• /
• v.18 no.3
• /
• pp.107-123
• /
• 2013

In a wireless sensor network environment, it is required to ensure anonymity by keeping sensor nodes' identifiers not being revealed and to support real-time authentication, lightweight authentication and synchronization. In particular, there exist possibilities of location information leakage by others, privacy interference and security vulnerability when it comes to wireless telecommunications. Anonymity has been an importance issue in wired and wireless network environment, so that it has been studied in wide range. The sensor nodes are interconnected among them based on wireless network. In terms of the sensor node, the researchers have been emphasizing on its calculating performance limit, storage device limit, and smaller power source. To improve of biometric-based D. He scheme, this study proposes a real-time authentication protocol using Unique Random Sequence Code(URSC) and variable identifier for enhancing network performance and retaining anonymity provision.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.11
• /
• pp.5897-5901
• /
• 2012

The aim of the study was to clarify the role of gastrokine 1 in the process of formation and development of gastric cancer. The expression of gastrokine 1 in gastric cancer and corresponding non-cancerous gastric tissues of 52 gastric cancer patients was assessed with the real-time fluorescence quantitative polymerase chain reaction (RT-PCR) and immunohistochemistry. We also analyzed the relationship between the expression level and clinicopathological characteristics. Gastrokine 1 gene and protein expression in gastric cancer tissues was in both cases significantly lower than in corresponding non-cancerous gastric tissues (both P<0.01), but no significant relationship was found with clinicopathological parameters including tumor location, depth of invasion, differentiation, lymph node metastasis, stage, gender, age and carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9) level in peripheral blood preoperation of patients (P>0.05, respectively). Furthermore, gastrokine 1 gene expression was markedly lower in gastric cancer tissues of Helicobacter pylori (HP)-positive patients than negative ones (P<0.05). The result of the study showed that gastrokine 1 might play a significant role in the process of formation and development of gastric cancer as an anti-oncogene. Its effect might be weakened by HP infection.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.2
• /
• pp.715-718
• /
• 2012

The current research concerns the clinicopathological significance of MHC class I chain-related protein A (MICA) expression in oral squamous cell carcinomas (OSCCs). The expression and location of MICA protein in 14 normal oral mucous and 45 cancerous and para-cancerous tissues were assessed by immunohistochemistry and levels of MICA mRNA expression in 29 cancerous and para-cancerous tissues were determined by the real-time polymerase chain reaction. Data were analyzed with the SPSS16.0 software package. MICA was found to be located in the cytoplasm and plasma membrane. Expression was higher in para-cancerous than in cancerous tissues (P < 0.05). However, no statistical difference was found between the following: 1) para-cancerous tissue with normal mucosa; 2) normal mucosa with cancerous tissue;and 3) among different clinicopathological parameters in OSCC (P > 0.05). The level of MICA mRNA was higher in OSCCs than in para-cancerous tissues, and was correlated with the regional lymph node status and disease stage (P < 0.05). The levels of MICA protein and mRNA expression differ among normal oral mucosa, para-cancerous tissue, and cancerous tissue. MICA may contribute to the tumorigenesis and progression of OSCC.

• Journal of Intelligence and Information Systems
• /
• v.23 no.2
• /
• pp.89-105
• /
• 2017

As the advances of technology in mobile networking and the popularity of online social networks (OSNs), the mobile social networks (MSNs) provide opportunities for marketing strategy. Therefore, understanding the information diffusion in the emerging MSNs is a critical issue. The information diffusion address a problem of how to find the proper initial nodes who can effectively propagate as widely as possible in the minimum amount of time. We propose a new diffusion scheme, called Hotspot DBC, which is to find k influential nodes considering each node's mobility behavior in the hotspot zones. Our experiments were conducted in the Opportunistic Network Environment (ONE) using real GPS trace, to show that the proposed scheme results. In addition, we demonstrate that our proposed scheme outperforms other existing algorithms.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.12
• /
• pp.2401-2409
• /
• 2015

This paper proposes the improved handoff mechanism for IEEE 802.11 wireless LANs. When a wireless mobile node moves out of the coverage of its currently associated AP(Access Point) and needs to be re-associated with a new AP, a handoff procedure is initiated. Channel scanning process during a handoff procedure occupies over 90% of total handoff latency. Long latency leads to many packet losses and service discontinuity, which degrades wireless network performance. This paper describes about the new mechanism to improve handoff performance by skipping channel scanning during a handoff procedure. In oerder for that, acquires neighboring AP information such as its address, location, channel number in use, the number of associated nodes before handoff, and delivers the information to its associated mobile nodes. The mobile nodes can reduce handoff latency and perform more exact handoff using the delivered AP information. We have conducted simulations to analyze our proposal's performance and confirmed that handoff latency and the number of handoff occurrences are decreased.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.6
• /
• pp.447-451
• /
• 2003

When sowing green peas in the autumn, proper seedling stands and growth quantity should be secured before winter begins. Also, for proper acclimatization, injuries caused by low temperatures, frost or high temperatures in the P.E. film during mulching, should be avoided during the regeneration period; that being early spring. The days required for growth in each stage in Yeosu are shorter than those in Naju because Yeosu has high temperatures during the growth period. Furthermore, in Yoesu, it was observed that there were more effective branches as well as effective and attached node positions on the branches. The first pods on the main stems and effective branches were observed to be higher than those in Naju. The number of pods per plant and the number of seeds per pod in Yoesu was greater than for those in Naju and the pod length was longer as well. Considering the missing plant rate, growth, and green pod yield, the optimum sowing date for the green pea was mid-November in both location. The stable acclimatizing date for the green pea was early March when the highest yield can be acquired due to a lot of effective branches and pods per plant and with the lowest missing plant rate and rate of injury in acclimatization.

• Journal of Korea Spatial Information System Society
• /
• v.6 no.1 s.11
• /
• pp.3-17
• /
• 2004

With the rapid growth of the Internet geographic information services through the WWW such as a location-based service and so on. Web GISs (Geographic Information Systems) have also come to be a cluster-based architecture like most other information systems. That is, in order to guarntee high quality of geographic information service without regard to the rapid growth of the number of users, web GISs need cluster-based architecture that will be cost-effective and have high availability and scalability. This paper proposes the design of the cluster-based web GIS with high availability and scalability. For this, each node within a cluster-based web GIS consists of main memory spatial databases which accomplish role of caching by using data declustering and the locality of spatial query. Not only simple region queries but also the proposed system processed spatial join queries effectively. Compare to the existing method. Parallel R-tree spatial join for a shared-Nothing architecture, the result of simulation experiments represents that the proposed spatial join method achieves improvement of performance respectively 23% and 30% as data quantity and nodes of cluster become large.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.2 no.1
• /
• pp.19-24
• /
• 2007

Abstract. In the ubiquitous environment of the next generation, RFID is predicted to occupy an important technical location and also expected to apply to various fields. However, the properties of tags in itself which is the core of RFID have a dysfunction like an invasion of privacy for user. An existing cryptanalytic protection scheme of the information leakage have a difficult problem to apply to RFID tags for privacy protection. We applied Ohkubo et al.'s scheme to the protection of the tag's information efficiently in the RFID system environment using low-cost tags. But, this method has all informations of tagsto identify tag's ID and then performs the process of identification in sequence in the Back-end server. These processes have lots of computations so that it have problems about a scalability. In this paper, we are based on Ohkubo et al.'s scheme to solve problems, and then analyze the parallelism with the Hellman's tradeoff method, divide it into nodesin parallel. In this paper, we are based on Okubo et al.'s scheme to solve problems, and then analyze the parallelism with Hellman's tradeoff method, divide it into the ${\omega}$ node in parallel. as a result, we can reduce the computing complexity of key search to $O(\frac{m^{2/3}n^{2/3}}{\omega})$ seconds from O(mm) seconds. finally we show the results to be enhanced the scalability.

• Journal of Korea Multimedia Society
• /
• v.12 no.9
• /
• pp.1191-1200
• /
• 2009

The replicas in the Grid database is utilized for a lot of application services. And for deferent services or for deferent information depends on location, the access frequency of each replica is dissimilar. When one replica is stored in many nodes, each replicas applies the week-consistency in the grid computing environment. Especially, when a node work load or operation capacity is varied from others, the replica management would cost expansive. Therefore, this paper proposed the Update Method based on Dynamic Access-Frequency Tree. The dynamic access-frequency tree is pre-constructed by grouping nodes based on each nodes access frequency to manage the replica efficiently and avoid unbalance replica tree. The performance evaluation shows the proposed methods support more quick update than current methods.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.12
• /
• pp.2221-2229
• /
• 2006

Optimal path search algorithm which is a killer application of mobile device to utilize location information should consider traffic flows of the roads as well as the distance between a departure and destination. The existing path search algorithms, however, are net able to cope efficiently with the change of the traffic flows. In this paper, we propose a new optimal path search algorithm. The algorithm takes the current flows into consideration in order to reduce the cost to get destination. It decomposes the road network into Fixed Grid to get variable heuristics. We also carry out the experiments with Dijkstra and Ar algorithm in terms of the execution time, the number of node accesses and the accuracy of path. The results obtained from the experimental tests show the proposed algorithm outperforms the others. The algorithm is highly expected to be useful in a advanced telematics systems.