Network Structure-Aware Ant-Based Routing in Large-Scale Wireless Sensor Networks

Kim, Kyungdoh,Ha, Chunghun,Ok, Changsoo Taylor & Francis 2015 INTERNATIONAL JOURNAL OF DISTRIBUTED SENSOR NETWOR Vol.2015 No.-

<P>Routing algorithms for large-scale sensor networks should be capable of finding energy efficient paths to prolong the lifetime of the networks in a decentralized manner. With this respect, Ant System has several proper characteristics for routing algorithm in large-scale wireless sensor networks. First, its distributed mechanism enables routing algorithm to find a solution with only local information and be robust for uncertainties in wireless sensor networks. Second, the framework of the Ant System is proper to solve dynamic problems such as routing problem. Transition probability in Ant System can be used to estimate how good a given routing path is. Capturing these features, this work proposes two Ant Systems based routing algorithms, which are AS-RWSNs (Ant System for Routing in Wireless Sensor Networks) and SAAS-RWSN (Structure-Aware AS-RWSN). The AS-RWSN applies the original Ant System to routing algorithm for wireless sensor network and SAAS-RSN upgrades AS-RWSN with considering properties of network structure such as degree of node. In SAAS-RSN, sensors with high node degree have high data traffic since they have more routing paths. Consequently, SAAS-RSN achieves an energy balance over sensor network through this routing scheme. We demonstrate the effectiveness of the proposed algorithms by comparing three existing routing algorithms.</P>

Comparison between Overview Menu and Text Menu in Smartphone

Kyungdoh Kim 대한인간공학회 2013 大韓人間工學會誌 Vol.32 No.6

Objective: This study determines which of two types of 2D menu is better on iPhone. Background: Menu systems have been important components in modern graphical user interfaces. Review of menu design studies for human-computer interaction suggests that menu design guidelines for smartphones need to be reappraised. Method: A nested factorial design was used. Twenty-four participants were divided into two groups. The subjects were nested within the menu type. Two types of menus are an overview menu and a text menu. Two different breadth levels are 16 and 64. The participants performed five tasks in each breadth level. A task is defined as locating a product or product class on the deepest level of the hierarchy. An Apple iPhone 2G was used. Results: The results for ANOVA indicated a lack of a significant difference for time to respond between the two types of 2D menus. The overview menu showed the better satisfaction score between the two menu types. Conclusion: Even though the differences were not significant, an overview menu tended to show better performance and preference scores than a text menu that required scrolling. Application: This study can provide menu design guidelines when 2D menus are considered for small displays in a high breadth level.

Fairness-based Bidding Model for Renewable Portfolio Standard Policy in South Korea Standard Policy in South Korea

Kim Youngdong,Kim Kyungdoh,Seok Hyesung 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

The share of renewable energy has already exceeded that of nuclear power in the United Kindom, Germany (by 30%), and Japan (10%), whereas the supply of alternative energy in South Korea is significantly less than that of advanced countries. In 2011, South Korea ended the feed-in-tariff operation and implemented renewable portfolio standards (RPSs), which require producers or sellers of electricity to supply a specified percentage of electricity generated or sold from renewable energy sources. Each operator receives renewable energy certificates corresponding to the amount of electricity supplied from renewable energy sources, allowing them to sell excess electricity or buy electricity to manage a deficit. Although the RPS ensures fairness by specifying separate quantities that can be sold based on each operator’s capacity, it focuses more on effectiveness. In this study, RPSs are investigated from the perspectives of effectiveness and fairness, and a new bidding model that further considers fairness is developed.

Investigation of physical and emotional attributes influencing user satisfaction of pens

Jinho Ahn,Kyungdoh Kim 대한인간공학회 2016 대한인간공학회 학술대회논문집 Vol.2016 No.06

Investigating Smart TV Gesture Interaction Based on Gesture Types and Styles

Junyoung Ahn,Kyungdoh Kim 대한인간공학회 2017 大韓人間工學會誌 Vol.36 No.2

Objective: This study aims to find suitable types and styles for gesture interaction as remote control on smart TVs. Background: Smart TV is being developed rapidly in the world, and gesture interaction has a wide range of research areas, especially based on vision techniques. However, most studies are focused on the gesture recognition technology. Also, not many previous studies of gestures types and styles on smart TVs were carried out. Therefore, it is necessary to check what users prefer in terms of gesture types and styles for each operation command. Method: We conducted an experiment to extract the target user manipulation commands required for smart TVs and select the corresponding gestures. To do this, we looked at gesture styles people use for every operation command, and checked whether there are any gesture styles they prefer over others. Through these results, this study was carried out with a process selecting smart TV operation commands and gestures. Results: Eighteen TV commands have been used in this study. With agreement level as a basis, we compared the six types of gestures and five styles of gestures for each command. As for gesture type, participants generally preferred a gesture of Path-Moving type. In the case of Pan and Scroll commands, the highest agreement level(1.00) of 18 commands was shown. As for gesture styles, the participants preferred a manipulative style in 11 commands (Next, Previous, Volume up, Volume down, Play, Stop, Zoom in, Zoom out, Pan, Rotate, Scroll). Conclusion: By conducting an analysis on user-preferred gestures, nine gesture commands are proposed for gesture control on smart TVs. Most participants preferred Path-Moving type and Manipulative style gestures based on the actual operations. Application: The results can be applied to a more advanced form of the gestures in the 3D environment, such as a study on VR. The method used in this study will be utilized in various domains.

Foreword: Special Issue Title: International Symposiums on Ergonomics and Human Factors Held by Ergonomics Society of Korea (ESK) in 2021 and 2022

Inseok Lee,Taezoon Park,Kyungdoh Kim 대한산업공학회 2024 Industrial Engineeering & Management Systems Vol.23 No.1

Progress Spinner의 진행 패턴 차이가 사용자의 인지 진행 속도 및 만족도에 미치는 영향 연구

박경진(Kyeongjin Park),김경도(Kyungdoh Kim) 대한산업공학회 2017 대한산업공학회지 Vol.43 No.3

Progress indicators provide information about downloading progress and the remaining time. Two common forms of indicator are bar and spinner. However, most studies have focused on the form of bar. Therefore, we are going to investigate which patterns of progress spinner show better perceived speed and satisfaction. Also the effects of provision of time information were studied. This study provided the progress spinner with different patterns with 4 seconds and 12 seconds download latencies. The participants evaluated overall satisfaction and perceived downloading speed. As a result, ‘Speed Up’ patterns showed the higher perceived downloading speed and satisfaction than ‘Speed Down’ patterns. In 4s situation, it was better with time information was absent. In 12s situation, it was higher in terms of the perceived downloading speed when time information was provided.

스마트폰에서의 텍스트 입력을 위한 커서 조작 방식 연구

안준영(Junyoung Ahn),김경도(Kyungdoh Kim) 대한산업공학회 2016 대한산업공학회지 Vol.42 No.5

The soft keyboard with touch interaction is universally available on mobile phone, a variety of previous studies with respect to the soft keyboard on smart devices had been conducted. However, previous studies of cursor control for text entry on smart devices such as smartphone did not performed. In this study, we compared three types of cursor controls (Default, 3D touch, Slide) in smartphone using Fitts’ law and C-D ratio. Then we performed a laboratory experiment with three cursor control types and evaluated using cursor movement time as a quantitative evaluation and 8 subjective metrics for usability as a qualitative evaluation. Then, we discussed what types of cursor control showed better performance and subjective satisfaction through their results. From these results, this study recommended the design guidelines for cursor control on smartphones and developed its study methods as our contributions.

Application of Color Information to Facilitate Finding Books in the Library

Kyeongjin Park,Hyeon Chul Kim,Eun Hye Lee,Kyungdoh Kim 대한인간공학회 2017 大韓人間工學會誌 Vol.36 No.3

Objective: We propose to apply color information to facilitate finding books in the library. Background: Currently, books are classified in the basis of a decimal classification system and a call number in the library. Users find a book using the call number. However, this classification system causes various difficulties. Method: In a process analysis and survey study, we identify what the real problem is and where the problem is occurred. To solve the real problems, we derived a new search method using color information. We conducted a comparative experiment with 48 participants to see whether the new method can show higher performance. Results: The new method using color information showed faster time and higher subjective rating scores than current call number method. Also, the new method showed faster time regardless of the skill level while the call number method showed time differences in terms of the skill level. Conclusion: The effectiveness of the proposed method was verified by experiments. Users will be able to find the desired book without difficulty. This method can improve the quality of service and satisfaction of library use. Application: Our book search method can be applied as a book search tool in a real public library. We hope that the method can provide higher satisfaction to users.

드론 촬영 제어 인터페이스 연구

박경진(Kyeongjin Park),김경도(Kyungdoh Kim) 대한인간공학회 2018 대한인간공학회 학술대회논문집 Vol.2018 No.11