• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1921-1926
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• 2003

We build a local minimum free motion planning for mobile robots considering dynamic environments by simple sensor fusion assuming that there are unknown obstacles which can be detected only partially at a time by proximity sensors and can be cleaned up or moved slowly (dynamic environments). Potential field is used as a basic platform for the motion planning. To clear local minimum problem, the partial information on the obstacles should be memorized and integrated effectively. Sets of linked line segments (SLLS) are proposed as the integration method. Then robot's target point is replaced by virtual target considering the integrated sensing information. As for the main proximity sensors, we use laser slit emission and simple web camera since the system gives more continuous data information. Also, we use ultrasonic sensors as the auxiliary sensors for simple sensor fusion considering the advantages in that they give exact information about the presence of any obstacle within certain range. By using this sensor fusion, the dynamic environments can be dealt easily. The performance of our algorithm is validated via simulations and experiments.

• Journal of Korea Multimedia Society
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• v.9 no.12
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• pp.1709-1718
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• 2006

Users are able to use the information and service more free than previous wire network due to development of wireless network and device. For this reason, various studies on ubiquitous networks have been conducted. Various contexts brought in this ubiquitous environment, have recognized user's action through sensors. This results in the provision of better services. Because services exist in various places in ubiquitous networks, the application has the time of services searching. In addition, user's context is very dynamic, so a method needs to be found to recommend services to user by context. Therefore, techniques for reducing the time of service and increasing accuracy of recommendation are being studied. But it is difficult to quickly and appropriately provide large numbers of services, because only basic context information is stored. For this reason, we suggest DUPS(Dimension User Profile System), which stores location, time, and frequency information of often used services. Because previous technique used to simple information for recommending service without predicting services which is going to use on future, we can provide better service, and improve accuracy over previous techniques.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1098-1102
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• 2014

Localization of aerial vehicles and map building of flight environments are key technologies for the autonomous flight of small UAVs. In outdoor environments, an unmanned aircraft can easily use a GPS (Global Positioning System) for its localization with acceptable accuracy. However, as the GPS is not available for use in indoor environments, the development of a SLAM (Simultaneous Localization and Mapping) system that is suitable for small UAVs is therefore needed. In this paper, we suggest a vision-based SLAM system that uses vision sensors and an AHRS (Attitude Heading Reference System) sensor. Feature points in images captured from the vision sensor are obtained by using GPU (Graphics Process Unit) based SIFT (Scale-invariant Feature Transform) algorithm. Those feature points are then combined with attitude information obtained from the AHRS to estimate the position of the small UAV. Based on the location information and color distribution, a Gaussian process model is generated, which could be a map. The experimental results show that the position of a small unmanned aircraft is estimated properly and the map of the environment is constructed by using the proposed method. Finally, the reliability of the proposed method is verified by comparing the difference between the estimated values and the actual values.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4588-4603
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• 2014

In this paper, we present a high-quality image authentication scheme based on absolute moment block truncation coding. In the proposed scheme, we use the parity of the bitmap (BM) to generate the authentication code for each compressed image block. Data hiding is used to authenticate whether the content has been altered or not. For image authentication, we embed the authentication code to quantization levels of each image block compressed by absolute moment block truncation coding (AMBTC) which will be altered when the host image is manipulated. The embedding position is generated by a pseudo-random number generator for security concerned. Besides, to improve the detection ability we use a hierarchical structure to ensure the accuracy of tamper localization. A watermarked image can be precisely inspected whether it has been tampered intentionally or incautiously by checking the extracted watermark. Experimental results demonstrated that the proposed scheme achieved high-quality embedded images and good detection accuracy, with stable performance and high expansibility. Performance comparisons with other block-based data hiding schemes are provided to demonstrate the superiority of the proposed scheme.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.9
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• pp.4412-4428
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• 2018

The purpose of this work is to solve the problem of representing an entire video using Convolutional Neural Network (CNN) features for human action recognition. Recently, due to insufficient GPU memory, it has been difficult to take the whole video as the input of the CNN for end-to-end learning. A typical method is to use sampled video frames as inputs and corresponding labels as supervision. One major issue of this popular approach is that the local samples may not contain the information indicated by the global labels and sufficient motion information. To address this issue, we propose a binary hashing method to enhance the local feature extractors. First, we extract the local features and aggregate them into global features using maximum/minimum pooling. Second, we use the binary hashing method to capture the motion features. Finally, we concatenate the hashing features with global features using different normalization methods to train the classifier. Experimental results on the JHMDB and MPII-Cooking datasets show that, for these new local features, binary hashing mapping on the sparsely sampled features led to significant performance improvements.

• Industrial Engineering and Management Systems
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• v.11 no.4
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• pp.353-370
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• 2012

Korea has shown a tremendous leap in economic development in a short span of time, and the world is watching Korea's economy with keen interest. Development of industries that are implementing information systems (IS) has played a role in leading economic growth in Korea. Because of the success of Korean firms, the creation of case studies for implementing IS in Korean firms was attempted. Despite the many case studies, analysis of the motivations and results, for implementing IS as a firm's strategic purpose, was rarely conducted. Therefore, this paper investigates some Korean firms' cases studies in order to show the best practice example of implementing and adopting IS strategically. Nine cases of Korean firms' strategic use of IS were analyzed in various industry fields. Each case consists of the following four categories: company overview, background implementing IS, adoption of IS for strategic purpose, and the results of implementing IS. In order to help various companies to take an action with their IS implementation and its strategic use, implications from the cases are summarized to show how Korean firms strategically introduced IS for solving particular problems that they had faced.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.116-132
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• 2022

Automated medical claims processing and billing is a popular application domain of information technology. Managing medical related data is a tedious job for healthcare professionals, which distracts them from their main job of healthcare. The technology used in data management has a sound impact on the quality of healthcare data. Most of Information Technology (IT) organizations use conventional software development technology for the implementation of healthcare systems. The objective of this experimental study is to devise a mechanism for use of rule-based expert systems in medical related edits and compare it with the conventional software development technology. A sample of 100 medical edits is selected as a dataset to be tested for implementation using both technologies. Besides empirical analysis, paired t-test is also used to validate the statistical significance of the difference between the two techniques. The conventional software development technology took 254.5 working hours, while rule-based technology took 81 hours to process these edits. Rule-based technology outperformed the conventional systems by increasing the confidence value to 95% and reliability measure to 0.462 (which is < 0.5) which is three times more efficient than conventional software development technology.

• Journal of Preventive Medicine and Public Health
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• v.41 no.4
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• pp.241-248
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• 2008

Objectives: The purpose of the study was to identify a gap between consumer characteristics and utilization of health information on the Internet. Methods: A telephone survey of nationally representative samples was conducted using structured questionnaires, and 1,000 of the 1,189 responses obtained were included in our analysis. The following variables were included in the analysis as potential predictors of health information use on the Internet: predisposing factors such as gender, age, and education status; enabling factors such as region and monthly household income; consumer need for health information; and attitude to health. Multiple logistic regression analysis was used to evaluate the association between utilization rate and the potential predictors. Results: Thirty-nine percent of consumers had obtained health information on the Internet over a one-year period. The utilization rates were higher for consumers who were young, educated, worked in the office setting, had higher incomes, wanted health information, and were able to use the Internet. The utilization rate was 5.35 times higher in the younger group (20-30 years) than in the elderly group (95% CI=2.21-12.97); 2.21 times higher for office workers than for manual workers (95% CI=1.16-4.20); 3.61 times higher for college graduates than for middle school graduates and below (95% CI=1.07-11.59); 1.99 times higher for people with monthly household incomes over 3,000,000 won than for those with monthly household incomes below 1,500,000 won (95% CI=1.01-3.92). Conclusions: There needs to be a paradigm shift, with consideration of not only Internet accessibility in the digital age, but also consumer ability and attitudes toward utilization of health information.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.4
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• pp.21-29
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• 2007

The National Geographic Information Clearinghouse (NGIC) in Korea has been established to share dispersed geographic information in many government organizations. The NGIC has become a main hub for sharing and exchanging geographic information in Korea. However, due to rapid technological advancement, citizens not only require more information but also demand more functions for NGIC. In this regards, this research tries to find the way of developing NGIC from a means of 'information sharing' to an arena of 'information use'. To do so, it suggests new technical frameworks and functionalities for NGIC. Then it recommend policy measures to improve current NGIC.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.5
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• pp.45-54
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• 2011

Currently various applications related to bus route are used on smart devices to obtain bus arrival times, and route information. However, applications are unable to provide various ways for users to provide their destination. This study has designed an algorithm based on user's six patterns. An Android application and a server that communicate with each other have been based on the algorithm. The applications and the server use the Google Maps service and location-based information to provide users with possible routes from the starting place to the destination. They also provide user's with users' current position and any transfer information. They provide practical and efficient information, and are easy to use.