• 한국기계기술학회지
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• 제20권6호
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• pp.912-916
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• 2018

Crawling robots are advantageous in overcoming obstacles. These robots have characteristics such as light weight and outstanding mobility. In case of large robots, they have difficulties passing narrow gaps or entering the cave. In this paper, we propose a milli-scale hexapedal robot using 4-bar linkages. Two conditions are necessary to enable efficient walking. In short, the trajectory of the foot must be elliptical, and the lowest point of the foot should be the same. These conditions are satisfied with a novel leg design. The robot has a pair of three legs and the legs are coupled to operate simultaneously. Each set of the legs are installed to robot's both sides and the legs satisfy the equal lowest foot point and elliptical trajectory. As a result, this hexapedal robot can crawl with 0.56m/s speed.

• 전기학회논문지
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• 제58권3호
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• pp.632-638
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• 2009

Probabilistic Latent Semantic Analysis has many applications in information retrieval and filtering, natural language processing, machine learning from text, and in related areas. In this paper, we propose an algorithm using weighted Probabilistic Latent Semantic Analysis Model to find the contextual phrases and opinions from documents. The traditional keyword search is unable to find the semantic relations of phrases, Overcoming these obstacles requires the development of techniques for automatically classifying semantic relations of phrases. Through experiments, we show that the proposed algorithm works well to discover semantic relations of phrases and presents the semantic relations of phrases to the vector-space model. The proposed algorithm is able to perform a variety of analyses, including such as document classification, online reputation, and collaborative recommendation.

• 로봇학회논문지
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• 제5권2호
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• pp.135-142
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• 2010

Security robot has gradually developed and deployed in order to protect civilian's lives as well as fortune and subjugate the shortcomings of CCTV which lacks of mobility. We have developed a security robot for outdoor environment and the main purpose of the driving mechanism is to overcome the bumps or projections with high speed. The robot platform consists of 4 omnidirectional wheel-based driving mechanisms and suspension for each driving mechanism. In this paper, principal suspension parameters of outdoor security robot for overcoming obstacles with stability are studied and approximately optimized using Response Surface Methodology (RSM) since it is difficult to find the exact relationship between suspension parameters and the shock, which is significantly associated with stability of the robot, at the robot platform. Simulation using ADAMS is conducted for assessing the feasibility of optimized design parameters.

• International Journal of Advanced Culture Technology
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• 제11권1호
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• pp.395-402
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• 2023

The implementation of a hybrid network utilizing Power Line Communication (PLC) and Wi-Fi technologies has been demonstrated to improve signal strength and coverage in areas with poor connectivity due to internet shadow areas. In this study we strategically positioned Wi-Fi relays and utilized the capabilities of PLC technology to significantly improve signal strength and coverage in areas with poor connectivity. We also analyzed the effects of metallic obstacles on Wi-Fi signal propagation and proposed a solution to strengthen the signal enough to pass through them. Our experiment demonstrated the feasibility and potential of using this hybrid network in industrial scenarios for real-time data transmission. Overall, the results suggest that the use of PLC and Wi-Fi hybrid networks can be a cost-effective and efficient solution for overcoming internet connectivity challenges and has the potential to provide high-speed internet access to areas with unreliable signals.

• 로봇학회논문지
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• 제5권1호
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• pp.14-22
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• 2010

Recently researches on the window cleaning robot are being conducted actively. Moving mechanismsof these window cleaning robots are divided into two categories, which are towed type and walking type. Towed type is focused on fast cleaning on the flat surface of building and walking type has priority on cleaning task on relatively complex surface with overcoming obstacles. Currently commercialized towed type window cleaning robot has weakness that it is hard to adhere closely with the wall and easy to be affected by wind. In case of walking type it has the problem that the position errors are continuously accumulated during motion. In this paper, we propose new towed and walking type mechanism which can compensate previous weaknesses. After that we estimate the performance of each proposed mechanism by simulation.

• 반도체디스플레이기술학회지
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• 제23권1호
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• pp.79-83
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• 2024

Digital Twin technology is rapidly transforming various industries by providing comprehensive virtual models that replicate physical objects or processes. In the context of agriculture, digital twin can be a game-changer. This technology can help in creating precise simulations of farming scenarios, thereby enabling farmers to make data-driven decisions and optimize farm operations. The potential benefits include improved crop yields, resource efficiency, and environmental sustainability. However, the implementation of digital twin technology in agriculture poses challenges, such as data management issues and the need for robust IoT infrastructure. Despite these hurdles, the future of digital twin in agriculture looks promising, with ongoing research and developments aimed at overcoming these obstacles.

• 한국보육지원학회지
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• 제13권6호
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• pp.43-67
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• 2017

Objective: The purpose of this study was to explore the feasibility to utilize image data recorded and accumulated from CCTV at child care centers. Methods: Literature reviews, consultations and workshops with scholars studying child development, legal professionals, and engineers, focus group interviews with professionals working with young children, and surveys targeting parents, directors and teachers were implemented. Results: It was found the big data from CCTV at child care centers can be used to make policies and implement research as a secondary data set after anonymization. Extracting implicit and useful data from images stored on CCTV is technically feasible. Also, it can be legally guaranteed to analyze the data under the condition of acquiring informed consents. Conclusion/Implications: It was likely to utilize image data from CCTV at child care centers as a secondary data set in order for policy development and scholarly purposes, after overcoming obstacles of the budget for additional infrastructures and consents of information holders.

• 아동학회지
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• 제28권6호
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• pp.53-72
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• 2007

The purpose of this study was to understand the meaning and nature of long term boarding care of children provided by grandparents in surrogate foster homes. Data were collected from 10 children 15 to 18 years of age by in depth interviews and observation from May 2007 to July 2007. Analysis of data was by the phenomenological analytic method of Giorgi(1970). Seven essential themes were extracted: (1) ambivalence about being labeled "family headed by a child," (2) recognition of the burden to grandparents with appreciation for their care, (3) resentment and yearning for parents, (4) economic hardship, (5) discord with grandparents, (6) maladjustment to school life, and (7) overcoming such obstacles as poor economic conditions and loneliness.

• 제어로봇시스템학회논문지
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• 제14권5호
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• pp.489-495
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• 2008

This paper offers a practical control scheme for driving mode transformation of a rescue robot already developed. The rescue robot, VSTR(Variable Single-Tracked Robot), has two driving modes, so can traverse untidy terrain and overcome obstacles such as stairs easily by use of timely driving mode transformation. Classical PI control scheme was used firstly for driving mode transformation, but stationary phenomenon, which might have a bad effect on the performance in real situation, came into existence. Therefore, we suggest a new controller, PI-based feedforward controller, which should be a good alternative for the problem, and compare it with other nonlinear control scheme.

• 한국어학
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• 제62권
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• pp.223-261
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• 2014

From the perspective of cross-cultural communication, it can be easily assumed that non-natives may have great difficulty understanding names of Korean dishes with covert information considering that even understanding those with overt information is a demanding task for them. Complex issues raised by cultural and linguistic differences hinder non-natives from having a clear understanding on names of Korean dishes. In order to resolve this problem, this paper focuses on providing clues to overcoming obstacles of cross-cultural communication in understanding names of Korean dishes by presenting issues including following cases:1. Analysis on types of Korean dish names with covert information in comparison to dish names with overt information. 2. Names of dishes made with a single contain covert information regarding a specific cooking and processing method. 3. A particular aspect regarding Korean food culture is that morphemes with a meaning of meat or flesh('gogi', 'sal', 'yook') contained in dish names indicate covert information that the dish is made of 'beef'.