• Journal of Satellite, Information and Communications
• /
• v.8 no.2
• /
• pp.62-67
• /
• 2013

Recently, users have been receiving LBS(Local Based Service) which provides various services. The LBS uses positioning information from satellites with using GPS(Global Positioning System). However, due to satellite signal's characteristics which are reflection and refraction in urban areas, users get unexpected positioning information error, expecially if there are so many tall buildings in a small area. To solve this problem, this paper offers a post-processing algorithm. It is consisted of users' direction vectors and positioning information. The positioning information with error is designed to be put on the direction vector. Through a car driving test in urban areas, we've got 11.1m(43%) improved result and demonstrated the superiority of its algorithm.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.14 no.2
• /
• pp.107-116
• /
• 2012

The experiment was performed to analyze the intersectional ventilation efficiency by intersection structure and Jet Fan in network-form road tunnel. For this, the size of real road tunnel was reduced by 1/45. To apply traffic inertia force when driving, blower fan was used to form an airflow in model tunnel and the intersectional efficiency was also investigated by measuring the speed at local point of the tunnel. To improve the reduction of ventilation caused by the structure character, Jet Fan was installed to optimize ventilation efficiency in tunnel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.120-123
• /
• 2009

The WiBro to start June 2006 is mobile internet service with 60km/h, 3Mbps. And current WiBro service is used in Seoul, the metropolitan area and the local major cities. This study suggests WiBro technology and analyzes wireless communication technology to vehicle-to-infrastructure communications for the unmanned vehicle control. We were driving vehicle with two laptop computer's WiBro unit for V2I communication environment. So each RAS(Radio Access Station) on center is tested coverage area, transmission rate, latency rate, lost rate and transmission rate to parking area environment.

• Journal of the Institute of Convergence Signal Processing
• /
• v.22 no.1
• /
• pp.38-44
• /
• 2021

Wi-Fi provides some low-power connection solutions that other Bluetooth cannot provide, and at the same time brings many benefits. First, there is a potentially higher data rate: it can reach 230mbps. Wi-Fi coverage is also wider than competitors, and its operating frequency is also 5GHz, which is much less congested than 2.4GHz. Finally, it also supports IP networks, which is important if you want to send data to the cloud without complexity. The 802.11ac standard of the previous generation still accounts for most shipments (80.9%) and revenue (76.2%). However, there is a limit to accepting IoT devices that will continue to increase significantly in the future. To solve this problem, the new Wi-Fi 6 standard is expected to be the solution (IEEE 802.11ax) which is quickly becoming the main driving force of the wireless local area network (WLAN) market. According to IDC market research analysts, in the first quarter of 2020, independent access points (APs) supported by Wi-Fi 6 accounted for 11.8% of shipments, but 21.8% of revenue. In this paper, we have compared and analyzed the IoT connectivity, QoS, and security requirements of devices using Wi-Fi 6 network.

• The Journal of Korea Robotics Society
• /
• v.16 no.2
• /
• pp.112-121
• /
• 2021

Unlike a typical small-sized robot navigating in a free space, an autonomous vehicle has to travel in a designated road which has lanes to follow and traffic rules to obey. High-Definition (HD) maps, which include road markings, traffic signs, and traffic lights with high location accuracy, can help an autonomous vehicle avoid the need to detect such challenging road surroundings. With space constraints and a pre-built HD map, a new type of path planning algorithm can be conceived as a substitute for conventional grid-based path planning algorithms, which require substantial planning time to cover large-scale free space. In this paper, we propose an obstacle-avoiding, cost-based planning algorithm in a continuous space that aims to pursue a globally-planned path with the help of HD map information. Experimentally, the proposed algorithm is shown to outperform other state-of-the-art path planning algorithms in terms of computation complexity in a typical urban road setting, thereby achieving real-time performance and safe avoidance of obstacles.

• Fourth Industrial Review
• /
• v.1 no.1
• /
• pp.31-40
• /
• 2021

Purpose - According to the importance of business simulation learning as a new type of business learning tool, this study reviews the dimensions of business education and a brief history of business education simulation. At the end Capsim strategic management simulation program is introduce with its feature. Research design, data, and methodology - This study has been analyzed in a way that reviews at previous literature on simulation learning and looks at examples and features of Capsim simulation, online business simulation tools which has been used in the global market. Result - Capsim simulations are designed to offer focused opportunities for deep practice. That's why they are often more effective than passive tools such as textbooks, videos, or lectures. By the way, 'deep practice' is very different from 'ordinary practice'. After commuters who drive to school or work can accumulate thousands of hours of driving, but that doesn't make them expert drivers. The key to deep practice is self-awareness. That is, paying attention to what you are doing well and not so well. This is so important to learn that scientists use a specific term for it: 'metacognition', or thinking about the way you think and learn. Conclusion - The use of business simulation learning, such as Capsim, which is a given case, can create similar local systems by potentially engaging a large number of users in the virtual market. It could also be used as an individual to complete business training for students and those who are active in the business field of business.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.159-160
• /
• 2021

We are facing major changes such as an aging population along with the 4th industrial revolution based on ICT technologies such as artificial intelligence, the Internet of Things, autonomous driving, and factory automation. For the local governments that are indexed in high population extinction risk, it is essential to consider market expansion and re-education policies suitable for regional characteristics in order to respond to changes such as advanced industrial automation and population aging. For the reemployment of the elderly, we will analyze previous public strategies for elderly-friendly jobs, expand investment in age-friendly industries. In this study, we suggest to improvement direction of the elderly labor market in Cheonan-Si.

• Asia-Pacific Journal of Business
• /
• v.14 no.3
• /
• pp.149-166
• /
• 2023

Purpose - This study aimed to examine the influence of various factors on customer satisfaction and the continuance usage intention, based on the purchasing type of smart speaker users. Design/methodology/approach - Data was gathered through surveys, collecting responses from 180 smart speaker users in Korea. Structural equation modeling was utilized to analyze the data. Findings - Both perceived usefulness and perceived security were observed to have a significant positive impact on customer satisfaction across all user groups. Moreover, perceived ease of use and perceived versatility showed a significant positive effect on the continuance usage intention. Notably, for those who acquired the smart speakers for free, perceived usefulness had a positive impact on the continuance usage intention. Conversely, for those who made a paid purchase, perceived versatility played a significant role in driving customer satisfaction. Research implications or Originality - This research offers insights into the Korean smart speaker market, a unique environment where local competitors thrive in the absence of giants like Amazon and Google. It provides a nuanced view of customer reactions to these innovative devices. The study further distinguishes between high-involvement (paid purchase users) and low-involvement (free acquisition users) consumers, offering a more detailed understanding of user perspectives based on their acquisition mode.

• Journal of Drive and Control
• /
• v.21 no.1
• /
• pp.46-52
• /
• 2024

The advancement of autonomous driving technology has heightened the importance of Autonomous Mobile Robotics (AMR) within smart factories. Notably, in tasks involving the transportation of heavy objects, the consideration of weight in route optimization and path planning has become crucial. There is ongoing research on local path planning, such as Dijkstra, A^*, and RRT^*, focusing on minimizing travel time and distance within smart factory warehouses. Additionally, there are ongoing simultaneous studies on route optimization, including TSP algorithms for various path explorations and on minimizing energy consumption in mobile robotics operations. However, previous studies have often overlooked the weight of the objects being transported, emphasizing only minimal travel time or distance. Therefore, this research proposes route planning that accounts for the maximum payload capacity of mobile robotics and offers load-optimized path planning for multi-destination transportation. Considering the load, a genetic algorithm with the objectives of minimizing both travel time and distance, as well as energy consumption is employed. This approach is expected to enhance the efficiency of mobility within smart factories.

• Journal of Advanced Navigation Technology
• /
• v.27 no.6
• /
• pp.861-864
• /
• 2023

Recently, V2X (vehicle-to-everyting) communication has established itself as an essential technology for cooperative autonomous driving. V2X communication currently includes DSRC (dedicated short range communication) communication technology, which is a WLAN (wireless local area network) based communication technology, and C-V2X (cellular-V2X) communication technology, which is a Cellular-based communication technology. Since these two communication methods are not compatible with each other, various studies and experiments are being conducted to select one of the two communication methods. In the case of C-V2X communication, there are LTE-V2X (long term evolutionV2X) communication technology, which is an initial version, and 5G-V2X communication technology, which is a next-generation version. 5G-V2X communication technology has been completed only until standardization, so LTE-V2X communication technology is mainly used. In this paper, we introduce trends related to various issues in V2X communication, including communication method decisions.