Vol. 3, No. 1, Jun. 2007
Kap-Dong Kim, Kwangil Lee, Jun-Hee Park, Sang-Ha Kim
Vol. 3, No. 1, pp. 1-7, Jun. 2007
Keywords: MANET Multicast Protocol, Overlay Multicast, Group Mobility
Show / Hide AbstractIn mobile ad hoc networks, an application scenario requires mostly collaborative mobility behavior. The key problem of those applications is scalability with regard to the number of multicast members as well as the number of the multicast group. To enhance scalability with group mobility, we have proposed a multicast protocol based on a new framework for hierarchical multicasting that is suitable for the group mobility model in MANET. The key design goal of this protocol is to solve the problem of reflecting the node¡¯s mobility in the overlay multicast tree, the efficient data delivery within the sub-group with group mobility support, and the scalability problem for the large multicast group size. The results obtained through simulations show that our approach supports scalability and efficient data transmission utilizing the characteristic of group mobility.
Tae-Wan Gu, Seong-Jun Hong, Saangyong Uhmn, Kwang-Mo Lee
Vol. 3, No. 1, pp. 8-15, Jun. 2007
Keywords: P2P, Membership Overlay, Membership Management, Hierarchical Ring
Show / Hide AbstractGrid environments provide the mechanism to share heterogeneous resources among nodes. Because of the similarity between grid environments and P2P networks, the structures of P2P networks can be adapted to enhance scalability and efficiency in deployment and to search for services. In this paper, we present a membership management based on a hierarchical ring which constructs P2P-like Grid environments. The proposed approach uses only a limited number of connections, reducing communication cost. Also, it only keeps local information for membership, which leads to a further reduction in management cost. This paper analyzes the performance of the approach by simulation and compares it with other approaches.
Hong Bum Son, Sung Gun Song, Jae Wook Jung, Chang Su Lee, Seong Mo Park
Vol. 3, No. 1, pp. 16-20, Jun. 2007
Keywords: Point-Of-Care, System-On-a-Programmable-Chip, Interface, Driver, Linux, ?C/OS-II
Show / Hide AbstractThis paper describes the development of the sensor interface and driver program for a point of care (POC) device. The proposed POC device comprises an ARM9 embedded processor and eightchannel sensor input to measure various bio-signals. It features a user-friendly interface using a fullcolor TFT-LCD and touch-screen, and a bluetooth wireless communication module. The proposed device is based on the system on a programmable chip (SOPC). We use Altera¡¯s Excalibur device, which has an ARM9 and FPGA area on a chip, as a test bed for the development of interface hardware and driver software.
A Practical Privacy-Preserving Cooperative Computation Protocol without Oblivious Transfer for Linear Systems of EquationsJu-Sung Kang, Dowon Hong
Vol. 3, No. 1, pp. 21-25, Jun. 2007
Keywords: SMC. Practical SMC, Privacy, Linear system of equations
Show / Hide AbstractWe propose several practical SMC protocols for privacy-preserving cooperative scientific computations. We consider two important scientific computations which involve linear equations: the linear systems of equations problem and the linear least-square problem. The protocols proposed in this paper achieve acceptable security in the sense of Du-Zhan¡¯s paradigm and t-wise collusionresistance, and their communication complexity is O(tm), where t is a security parameter and m is the total number of participants. The complexity of our protocol is significantly better than the previous result O(m©÷§¤¥ì) of , in which the oblivious transfer protocol is used as an important building block.
Ki-Tae Kim, Weon-Hee Yoo
Vol. 3, No. 1, pp. 26-32, Jun. 2007
Keywords: Bytecode, Control Flow Graph, Static Single Assignment, Static Type Assignment
Show / Hide AbstractAlthough the Java bytecode has numerous advantages, it also has certain shortcomings such as its slow execution speed and difficulty of analysis. In order to overcome such disadvantages, a bytecode analysis and optimization must be performed. The control flow of the bytecode should be analyzed; next, information is required regarding where the variables are defined and used to conduct a dataflow analysis and optimization. There may be cases where variables with an identical name contain different values at different locations during execution, according to the value assigned to a given variable in each location. Therefore, in order to statically determine the value and type, the variables must be separated according to allocation. In order to achieve this, variables can be expressed using a static single assignment form. After transformation into a static single assignment form, the type information of each node expressed by each variable and expression must be configured to perform a static analysis and optimization. Based on the basic type information, this paper proposes a method for finding the related equivalent nodes, setting nodes with strong connection components, and efficiently assigning each node type
Altangerel Chagnaa, Cheol-Young Ock, Chang-Beom Lee, Purev Jaimai
Vol. 3, No. 1, pp. 33-37, Jun. 2007
Keywords: Independent Component Analysis, Clustering, Latent Concepts.
Show / Hide AbstractSemantic clustering is important to various fields in the modern information society. In this work we applied the Independent Component Analysis method to the extraction of the features of latent concepts. We used verb and object noun information and formulated a concept as a linear combination of verbs. The proposed method is shown to be suitable for our framework and it performs better than a hierarchical clustering in latent semantic space for finding out invisible information from the data.
Dong-wan Hong, Jong-keun Lee, Sung-soo Park, Sang-kyoon Hong, Jee-hee Yoon
Vol. 3, No. 1, pp. 38-42, Jun. 2007
Keywords: Micro-array data, Functional analysis, Gene Ontology, Informative genes.
Show / Hide AbstractMicroarray data includes tens of thousands of gene expressions simultaneously, so it can be effectively used in identifying the phenotypes of diseases. However, the retrieval of functional information from a large corpus of gene expression data is still a time-consuming task. In this paper, we propose an efficient method for identifying functional categories of differentially expressed genes from a micro-array experiment by using Gene Ontology (GO). Our method is as follows: (1) The expression data set is first filtered to include only genes with mean expression values that differ by at least 3-fold between the two groups. (2) The genes are then ranked based on the t-statistics. The 100 most highly ranked genes are selected as informative genes. (3) The t-value of each informative gene is imposed as a score on the associated GO terms. High-scoring GO terms are then listed with their associated genes and represent the functional category information of the micro-array experiment. A system called HMDA (Hallym Micro-array Data analysis) is implemented on publicly available microarray data sets and validated. Our results were also compared with the original analysis.
Evens Jean, Yu Jiao, Ali R Hurson
Vol. 3, No. 1, pp. 43-53, Jun. 2007
Keywords: Disk Striping, Multimedia System, Bandwidth
Show / Hide AbstractThe use of agent paradigm in today¡¯s applications is hampered by the security concerns of agents and hosts alike. The agents require the presence of a secure and trusted execution environment; while hosts aim at preventing the execution of potentially malicious code. In general, hosts support the migration of agents through the provision of an agent server and managing the activities of arriving agents on the host. Numerous studies have been conducted to address the security concerns present in the mobile agent paradigm with a strong focus on the theoretical aspect of the problem. Various proposals in Intrusion Detection Systems aim at securing hosts in traditional client-server execution environments. The use of such proposals to address the security of agent hosts is not desirable since migrating agents typically execute on hosts as a separate thread of the agent server process. Agent servers are open to the execution of virtually any migrating agent; thus the intent or tasks of such agents cannot be known a priori. It is also conceivable that migrating agents may wish to hide their intentions from agent servers. In light of these observations, this work attempts to bridge the gap from theory to practice by analyzing the security mechanisms available in Aglet. We lay the foundation for implementation of application specific protocols dotted with access control, secured communication and ability to detect tampering of agent data. As agents exists in a distributed environment, our proposal also introduces a novel security framework to address the security concerns of hosts through collaboration and pattern matching even in the presence of differing views of the system. The introduced framework has been implemented on the Aglet platform and evaluated in terms of accuracy, false positive, and false negative rates along with its performance strain on the system.