Seongsoo Cho

An Energy-Efficient Cluster-Based Routing in Wireless Sensor Networks

In Wireless Sensor Networks (WSNs), sensor nodes depend on batteries for energy source. The ability to use limited energy efficiently is the key to determining the lifetime of networks and the amount of information transmitted. Low Energy Adaptive Clustering Hierarchy (LEACH) is a representative cluster-based routing protocol designed to ensure energy use efficiency. In this paper, a protocol scheme was proposed wherein member nodes (lower-level nodes) are designed to compare the currently sensed data with the previously sensed one and to switch to sleep mode when a match is achieved. The design is to help improve the transmission energy efficiency. The proposed scheme was tested via simulations and was compared with two existing cluster-based algorithms, i.e., LEACH and Threshold Sensitive Energy Efficient Sensor Network Protocol (TEEN). Performance evaluation was conducted based on the number of surviving nodes in each of the three networks (i.e., LEACH, TEEN, and proposed scheme) over time. The results indicated that the scheme contributed to greater energy efficiency by helping to increase the lifetime of the LEACH network by a maximum of 27%.

Energy Efficient Routing in Wireless Sensor Networks

Sensor nodes depend on batteries for energy source in Wireless Sensor Networks (WSNs). Low Energy Adaptive Clustering Hierarchy (LEACH) is a representative cluster-based routing protocol designed to ensure energy use efficiency whereas the virtual cluster exchange routing (VCR) information only with its closest node to build a network. In this paper, a protocol scheme was proposed wherein member nodes are designed to compare the currently sensed data with the previously sensed one and to switch to sleep mode when a match is achieved. The design is to help improve the transmission energy efficiency too.

English course E-learning system based on relative item difficulty using web component composition

Many researches about e-learning system have been applied item difficulty to increase learning effectiveness. And development environment was changed the internet based learning media contents into the more various technology such as component, web 2.0, service oriented development and so on. Especially, service-oriented development is one of new trend in web based system and has become mainstream in software development. In the development, web components aims at providing support to service-oriented technique by enabling automatic discovery, composition, invocation and interoperation of the services. In this paper, we aimed the implementation of English e-learning system including the item guessing parameter and considering the relative correction of item difficulty. In the system, a learner was given to choose the learning step by the relative difficulty. In order to process and combine, all the learning contents are based on Sharable Content Object Reference Model (SCORM) with Learning Management System (LMS). Also, each learning contents are belong to Sharable Content Objects (SCOs).

Development of Mobile Games for Rehabilitation Training for the Hearing Impaired

This research is to suggest a mobile game program for rehabilitation of the hearing impaired. The suggested program is based on the characteristics of hearing-impaired children and the classification of hearing loss. The voice recognition technology is the most intimate way of delivery of information. The suggested program does not require any additional learning or training course, but enables the hearing impaired to do vocal exercises through games and helps them to enjoy rehabilitation training.

Study of Generating Animated Character Using the Face Pattern Recognition

The similar character of input video image can be generated by combining each components points after extracting the position of each component points using the ratio of face. By selecting the face area, in case of the upper half image, the neck and stained hair become change and accuracy of recognition of selected area becomes low, so in order to compensate the area of inaccuracy, we can find the shape of face, eyes and mouth applying the golden ratio and the character is reflected in the results. Using color informations of the image of the face, the TSL color can be analysed and shown the face recognition ratio of 1.7%. The components in each five input images (left and right eyes, eyebrows and mouth) by selecting the test results showed the performance of 88.3%. By analyzing the characteristics of the elements found in those features automatically generate the appropriate characters, and the rabbit character can be automatically generated from the animation story of ‘Rabbit and Tortoise’ made by flash tool. Using the TSL color model, the face shape and the eyes, eyebrow, nose, mouth, and ears are visualised in a 2D. In the digital cultural content, the character is automatically generated by video input image and oneself can be staged as a hero in the animation which is the development of a new digital cultural contents.

Improvement of Retinex Algorithm for Backlight Image Efficiency

An image in a dynamic range widened by limitations in an image sensor, which has limited size of dynamic range, causes mobile phones and digital cameras to produce brightly saturated image or dark image with less exposure unlike observed with human eyes. This study, which explores solutions to improve contrast imbalance triggering higher global contrast but lower local contrast in images acquired in an environment with wide dynamic range, uses exposure information and edge information for weighted value mapping. The map is applied to image composition process to compare high-brightness proposed in the algorithm to improve contrast imbalance. The comparison indicates greater contrast improvement in the test image than in the original algorithm. Specifically, average growth rate in the original algorithm declined by roughly 27% generating a very large contrast loss while it declined by just 9% in the proposed algorithm resulting in hardly any loss. This comparison and numerical analysis point to the original contrast improvement performance to be a better choice as proven by the proposed algorithm, which does not incur contrast loss in the HD side and thus, produce a more balanced contrast improvement performance.

A Design and Implementation of Mobile Puzzle Game

This study has actualized Beadz Puzzle, a beads puzzle game, on the mobile where everyone can enjoy regardless of the location and time. Beadz Puzzle, increases the children’s ability in spatial perception, patience, and concentration and allows them to develop cognitive ability in different situations and enhance their intellectual capacity. Moreover, adolescents and adults can develop their ability to process things quickly; the aged can maintain quick thinking and prevent Alzheimer disease. Each question has different ways to solve so that various solutions can be examined. This study suggests a Beadz Puzzle that has been modified and supplemented from the original beads puzzle game by adding layers of levels, a time limit and life system. That is, this game is constructed as interactive games using Beads Puzzle, therefore, it also can induce more participation and interest of elderly persons by using various configurations of games.

Multipath routing technique for responding to sniffing attacks in wireless multimedia sensor network environment

As the image sensor modules such as complementary metal oxide semiconductor (CMOS) camera sensors and digital microphones are developed, security is required such as data storage and transmission in wireless multimedia sensor network technology and application. Data transmitting through existing sensor network routing path has the problem of high vulnerability to information leakage by sniffing attacks. Therefore, the study proposes one of the protection technique from a sniffing attack, which protects from attacking. The proposed technique is based on the movement of risk factors that sets priority of the geographically proximal sensor nodes according to defense readiness condition (DEFCON) and data importance. According to the simulation results, it achieved approximately 5.8% transmission delay time compared with existing sensor network path but the security was confirmed as eavesdropping rate where risk factors can attack and eavesdrop decreased by approximately 18.5%.

FOLI Technique Algorithm for Real-Time Efficient Image Processing

We proposed an image enhancement algorithm with less computational complexity than the existing one. In the proposed blocks for algorithm, the decimation filter provides the reduction of computational complexity using spatial reduction methods. The contrast enhancement block employs a probability density value (PDV) in order to control the excessive change of brightness. Cumulative distribution function (CDF) is estimated by using first order linear interpolation (FOLI) for real time processing. The colour enhancement block carries out saturation enhancement using saturation extension by maximum saturation enhancement (MSE) methods. It has been implemented in FPGA (field programmable gate array), and we have made an evaluation board for experiment. As compared to the conventional algoriths, the proposed algorithm provides better performance and lower computational complexity.

Moisture Sensor Design Using Spurline RF Resonator

This paper presents a miniaturized spurline microstrip RF resonator to moisture loaded organic material, soybean seeds using overlay technique. The permittivity has calculated from the frequency response of the moisturized seeds. The RF microstrip spuriine resonator with high Q is so sensitivity to the organic material that helps to sense the moisture content seeds and it is simulated and observed the frequency response at 10 GHz with insertion loss of 40 dB. The designed RF resonator has high quality factory (Q) which is good for using it as a sensor. The resonator can also be characterized using vector network analyzer before and after loading the soybean on the sensitive area of the resonator and we can have frequency difference due to difference in dielectric constant. Random orientations can be done while characterizing the spurline resonator.