• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.8
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• pp.3889-3903
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• 2017

Fast and accurate localization of randomly deployed nodes is required by many applications in wireless sensor networks (WSNs). However, mobile nodes localization in WSNs is more difficult than static nodes localization since the nodes mobility brings more data. In this paper, we propose a Range-based Monte Carlo Box (RMCB) algorithm, which builds upon the Monte Carlo Localization Boxed (MCB) algorithm to improve the localization accuracy. This algorithm utilizes Received Signal Strength Indication (RSSI) ranging technique to build a sample box and adds a preset error coefficient in sampling and filtering phase to increase the success rate of sampling and accuracy of valid samples. Moreover, simplified Particle Swarm Optimization (sPSO) algorithm is introduced to generate new samples and avoid constantly repeated sampling and filtering process. Simulation results denote that our proposed RMCB algorithm can reduce the location error by 24%, 14% and 14% on average compared to MCB, Range-based Monte Carlo Localization (RMCL) and RSSI Motion Prediction MCB (RMMCB) algorithm respectively and are suitable for high precision required positioning scenes.

• ETRI Journal
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• v.45 no.5
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• pp.836-846
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• 2023

Mobile robots are used in modern life; however, object recognition is still insufficient to realize robot navigation in crowded environments. Mobile robots must rapidly and accurately recognize the movements and shapes of pedestrians to navigate safely in pedestrian-rich spaces. This study proposes real-time, accurate, three-dimensional (3D) multi-pedestrian detection and tracking using a 3D light detection and ranging (LiDAR) point cloud in crowded environments. The pedestrian detection quickly segments a sparse 3D point cloud into individual pedestrians using a lightweight convolutional autoencoder and connected-component algorithm. The multi-pedestrian tracking identifies the same pedestrians considering motion and appearance cues in continuing frames. In addition, it estimates pedestrians' dynamic movements with various patterns by adaptively mixing heterogeneous motion models. We evaluate the computational speed and accuracy of each module using the KITTI dataset. We demonstrate that our integrated system, which rapidly and accurately recognizes pedestrian movement and appearance using a sparse 3D LiDAR, is applicable for robot navigation in crowded spaces.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.32 no.2
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• pp.49-67
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• 2021

The school library provides a mobile web service that allows access to the library catalog system, and provides services that reflect the needs of search and consider the characteristics of mobile devices. Therefore, this study conducted a literature review, an analysis of the current status of school library mobile web services, and a survey of the mobile service user experience of students and teachers to find the contents and service plans for school library mobile app services that meet the school library mobile needs. Based on the survey, the contents and design plan of the school library DLS mobile service was prepared. First, the steps were reduced from step 4 to step 3. In the first step, solution of screen clipping errors in registering as a member and various login platforms for accessibility are needed. In the second step, integrated search and detailed search, provision of materials for use and reading education, post-booking activities, guides and announcements on the use of the affiliated school library, inter-loan, and e-books are provided as main menu. In the third step, it was proposed to provide related functions such as reservations as well as the display of the detailed screen of the search results of the collection. This study can be used not only to develop dedicated mobile app services, but also to change current web-based mobile services.

• The Journal of Korean Association of Computer Education
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• v.15 no.5
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• pp.55-62
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• 2012

With the development of mobile communications and Internet technology, there is a strong need to provide seamless and fast connectivity for roaming devices. Generally, the mobile host (MH) may have several available networks when entering a new wireless area. However, the standard of decision for user's internet connection is provided only the subsystem identification (SSID) and signal strength of access point (AP). These two standards could not enough to decide optimal AP to the MH. Therefore, to decide the optimal AP, more information is needed. In this paper, we present additional information such as status of MH, capacity, current load, and depth of network hierarchy, by router advertisement message at layer 3. Also, we proposed decision engine (DE) on the MH that analyzes APs and decides the optimal AP automatically by AP's status information. For the MH, wireless connection period is increased, the power consumption is decreased, and the signaling overhead is reduced. For AP and router, the load balancing is provided and the network topology can also be more efficient.

• The Journal of Korean Association of Computer Education
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• v.12 no.5
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• pp.35-47
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• 2009

Just as noted in some studies related to U-learning based on the ubiquitous technology, it is required to reflect both factors of the environments and contexts of learners on the teaching and learning strategy. For this, the current paper suggests an inquiry learning method and a mobile learning support device for the inquiry learning. Since the inquiry learning is operating on the basis of the contents that learners themselves experience in the fields, it naturally leads them to position in the learning environments and contexts. In this study some curricula are adopted and transformed for the inquiry learning, and the developed mobile device for the learning has a guide function, so that learners might follow the inquiry learning process. In addition, it is possible to reuse the acquired learning data by storing them on a remote learning sever, which may support the inquiry learning of students. These system and device are applied in the teaching sites of schools and, consequently, it is found that in regard with the learning interest and academic performance of students there is an advanced result, being statistically significant.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.301-306
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• 2021

In the field of year-based interpretation of important data, memory laws can be used as a way to enhance educational effectiveness. Studies related to how to remember numbers are conducted in the form of increasing memory rates by presenting information in the form of conventional simple images. We attempt to supplement the method proposed in the paper of numerical algorithm for modifying errors based on mnemonic system in mobile environments. We want to complement the error correction numerical algorithm proposed in previous work. The study was a way to compensate the errors that occur when users enter numerical information in the apps they use. In this work, we want to increase the memory rate based on two-dimensional information by imposing the concept of angles, rather than simply showing data to help recall memories from mistakes. To this end, we propose a problem-solving process using developed app, and implement and evaluate the short distance valid algorithms.

• Educational Technology International
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• v.24 no.2
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• pp.115-141
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• 2023

The aim of this research is to understand the perceptions of primary and secondary teachers regarding educational resource sharing systems(ERS) by using a qualitative approach. This study conducted Focus Group Interview(FGI) with 20 primary and secondary school teachers. Interview data were analyzed through inductive content analysis method. The results are as follows. First, teachers placed significant emphasis on high-quality, convenient functions, and reward system for sharing resources. Specifically, teachers identified the necessity for a diverse array of materials, systematic categorization of these resources, and the provision of monetary compensation as essential components. Second, the study participants advocated strategies for revitalizing ERS including enhancing accessibility, constructing user-friendly features, increasing awareness, and establishing a reward system to incentivize the resource sharing. In particular, teachers proposed strategies such as developing mobile-based services and AIdriven data recommendation system. These results provide actionable insights for stakeholders engaged in the design, implementation, and evaluation of resource sharing platforms.

• Nutrition Research and Practice
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• v.18 no.2
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• pp.294-307
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• 2024

BACKGROUND/OBJECTIVES: Dietitians frequently use nutrition education tools to facilitate dietary counselling sessions. Nevertheless, these tools may require adaptation to keep pace with technological advancements. This study had a 2-fold purpose: first, to identify the types of nutrition education tools currently in use, identify their limitations, and explore dietitians' perspectives on the importance of these tools; second, to investigate the features that dietitians prefer in digital nutrition education tools. SUBJECTS/METHODS: A semi-structured face-to-face interview was conducted among 15 dietitians from selected public hospitals, primary care clinics, and teaching hospitals in Malaysia. Inductive thematic analysis of the responses was conducted using NVivo version 12 software. RESULTS: Most dietitians used physical education tools including the healthy plate model, pamphlets, food models, and flip charts. These tools were perceived as important as they facilitate the nutrition assessment process, deliver nutrition intervention, and are time efficient. However, dietitians described the current educational tools as impersonal, outdated, limited in availability due to financial constraints, unhandy, and difficult to visualise. Alternatively, they strongly favoured digital education tools that provided instant feedback, utilised an automated system, included a local food database, were user-friendly, developed by experts in the field, and seamlessly integrated into the healthcare system. CONCLUSION: Presently, although dietitians have a preference for digital educational tools, they heavily rely on physical nutrition education tools due to their availability despite the perception that these tools are outdated, impersonal, and inconvenient. Transitioning to digital dietary education tools could potentially address these issues.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.12
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• pp.2765-2772
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• 2015

In Korea MVNO was introduced in 2011 when twenty seven years had passed since Korea Mobile Telecom(now SK Telecom) started mobile phone service. MVNO can make competition more effective to lower communication costs through the alternatives. In the early 2000s, the need for the introduction of the MVNO has been raised already by scholars in Korea. But it wasn't until the late 2000s when rate cuts appeared to be a major policy issue, and Korean government introduced MVNO. In April 2015, MVNO's market share reached 8.8%, but Korea does not have a firm system yet. This rapid growth of MVNO market in Korea was made possible by consumers' demand for cheaper services and late introduction of MVNO. And telecom companies(MNO) abuse their supreme power against small and medium firm MVNOs and reserved market share using their subsidiary companies. Thus proper regulation is necessary. However, the government authorities should have recognized global MVNO flow quickly and have to make a sufficient effort to establish proper competition condition of the mobile telecom market.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.12A
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• pp.1181-1187
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• 2010

This paper proposes a mobile AI (Artificial Intelligence) conducting decision-making in the game through education for intelligent character on the basis of Neural Network. Neural Network is learned through the input/output value of the algorithm which defines the game rule and the problem solving method. The learned character is able to perceive the circumstances and make proper action. In this paper, the mobile AI using Neural Network has been step-by-step designed, and a simple game has been materialized for its functional experiment. In this game, the goal, the character, and obstacles exist on regular 2D space, and the character, evading obstacles, has to move where the goal is. The mobile AI can achieve its goals in changing environment by learning the solution to several problems through the algorithm defined in each experiment. The defined algorithm and Neural Network are designed to make the input/output system the same. As the experimental results, the suggested mobile AI showed that it could perceive the circumstances to conduct action and to complete its mission. If mobile AI learns the defined algorithm even in the game of complex structure, its Neural Network will be able to show proper results even in the changing environment.