• Current Optics and Photonics
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• v.7 no.2
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• pp.176-182
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• 2023

Optical coherence tomography (OCT) is being developed to guide various ophthalmic surgical procedures. However, the high cost of the intraoperative OCT system limits its availability mostly to the largest hospitals and healthcare systems. In this paper, we present a design and evaluation of a low-cost intraoperative common-path free-hand scanning OCT system. The lensed fiber imaging probe is designed and fabricated for intraocular use and the free-hand scanning algorithm that could operate at a low scanning speed was developed. Since the system operates at low frequencies, the cost of the overall system is significantly lower than other commercial intraoperative OCT systems. The assembled system is characterized and shows that it meets the design specifications. The handheld OCT imaging probe is tested on multilayer tape phantom and ex-vivo porcine eyes. The results show that the system could be used as an intraoperative intraocular OCT imaging device.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.109-115
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• 2001

The compliance approach to the problem of load sharing between a cracked plate and multiple plate used to bridge the crack. The theory is validated by using calculated stress intensity factors for the multiple load path plate to reduce experimentally observed growth rate to a common base. Calculations are them made on the effect of multiple load path plate width on fatigue crack retardation in order to demonstrate the predictive capability of the technique.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.577-579
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• 2004

Because the Resource reservation Protocol (RSVP) was originally designed fur stationary networks, it is insufficient to accommodate Mobile Nodes (MNs) which frequently change their points of attachment.7his paper deals with how to integrate the RSVP and Hierarchical MHv6 (HMIPv6), in order to quickly establish the QoS guaranteed path and minimize the service disruption when the MN moves around. That can be achieved with the utilization of the common path between the new and old path. Therefore a new method is proposed in detail to find out an anchor node and re-establish a new reservation path.

• Journal of the Society of Disaster Information
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• v.5 no.1
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• pp.30-44
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• 2009

Asphalt concrete pavements are often destroyed within the intended design life due to the increasement in traffic volume. The most common types of asphalt concrete pavement damages are permanent deformation and fatigue cracking, and so on. In this research, characteristics of traffic loadings and lateral wheel path distributions are analyzed using the field survey on traffic flow. The obtained traffic characteristics can be used to the decision making for the maintenance policy of roads. According to the traffic lane analysis for the 2nd and 3rd lanes, inner lane vehicles tended to pass to the right side to avoid the opposite side vehicles. In addition, the outside lane vehicles were deviated to the left side to avoid passengers. It is also noted that the lateral wheel path distributions was close to the normal distribution.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.36.4-36
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• 2001

A robust and reliable path recognition system is one necessary component for the autonomous navigation of a mobile robot to help determining its current position in its navigation map. This paper describes a computer visual path-recognition system using on-board video camera as vision-based driving assistance for an autonomous navigation mobile robot. The common problem for a visual system is that its reliability was often influenced by different lighting conditions. Here, two different image processing methods for the path detection were developed to reduce the effect of the luminance: one is based on the RGB color model and features of the path, another is based on the HSV color model in the absence of luminance.

• The Korean Journal of Community Living Science
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• v.25 no.1
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• pp.51-64
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• 2014

With a shift in the rural development process toward a bottom-up approach, the need to enhance the endogenous capacity of communities has become the core of rural development. In this regard, scholars have paid close attention to social capital to identify ways to facilitate endogenous rural development but focused mainly on relationships between social capital and local environment. That is, few studies have investigated the relationships between social capital and its various dimensions in the context of rural development initiatives. This study examines the effects of social capital on the problem-solving ability of community residents'rural development initiatives and assesses the types of social capital associated with such initiatives to propose optimal path for improving this ability. To distinguish between major dimensions of social capital, a questionnaire was developed by considering various stages of the rural development process. The survey considered a sample of 59 employees from public rural development institutions. According to the results, four paths were significant at the 5% level. Among these four paths, three set common goals. The effective channel was the path [common goals${\Rightarrow}$network${\Rightarrow}$cooperation${\Rightarrow}$problem-solving ability]. The key factor in improving problem-solving skills, the endogenous ability of community residents to facilitate rural development initiatives. The results suggest that governments should strengthen education and training programs to help residents set their common goals.

• Journal of Korea Multimedia Society
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• v.7 no.7
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• pp.859-876
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• 2004

This paper presents optimal configurations of multidimensional path indexes (MPIs) for the efficient execution of object-oriented queries in object databases. MPI uses a multidimensional index structure for efficiently supporting nested predicates that involve both nested attribute and class hierarchies, which are not supported by the nested attribute index using one-dimensional index structure such as $B^+$-tree. In this paper, we have analyzed the MPIs in the framework of complex queries, containing conjunctions of nested predicates, each one involving a path expression having target classes and domain classes substitution. First of all, we have considered MPI operations caused by updating of object databases, and the use of the MPI in the case of a query containing a single nested predicate. And then, we have considered the use of the MPIs in the framework of more general queries containing nested predicates over both overlapping and non-overlapping paths. The former are paths having common subpaths, while the latter have no common subpaths.

• Journal of Forest and Environmental Science
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• v.37 no.3
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• pp.260-268
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• 2021

This study was conducted to grasp users' preferences and behavior of forest paths and to provide basic data for forest path construction in the future. Among forest path users, males and females over 20 years old were surveyed on forest path preferences, motives for visiting, using time and distance, companions, and sources for obtaining information on forest paths. A total of 587 people participated in the questionnaire, and cross-analysis was conducted simultaneously using the SPSS statistical program. In analyzing the preference of forest paths, it was found that male and the general public preferred trekking path for activities while female and foresters preferred forest path for relaxation and healing (p<0.05). As for the motives for visiting forest paths, the response that they visited for a walk/rest was the highest in gender, occupation, and age group. As for the number of annual visits, less than 5 was the highest in overall, and foresters tended to visit forest path more often than the general public, and the number of visits to the forest paths increased with age (p<0.01). The most common route to acquire information about forest paths is the Internet, while the Internet use is relatively low in those over 60s (p<0.05). The response ratio of accompanying their family in visiting forest paths were the highest, while the response in their 20s and 60s was the most in accompanying their friends (p<0.05).

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1004-1008
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• 1990

This research focuses on developing a new and computationally efficient algorithm for free space structuring and planning collision free paths for an autonomous mobile robot working in an environment populated with polygonal obstacles. The algorithm constructs the available free space between obstacles in terms of free convex area. A collision free path can be efficiently generated based on a graph constructed using the midpoints of common free links between free convex area as passing points. These points correspond to nodes in a graph and the connection between them within each convex area as arcs in this graph. The complexity of the search for collision free path is greatly reduced by minimizing the size of the graph to be searched concerning the number of nodes and the number of arcs connecting them. The analysis of the proposed algorithm shows its efficiency in terms of computation ability, safety and optimality.

• Journal of KSNVE
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• v.8 no.3
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• pp.485-493
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• 1998

Many of the adaptive noise control systems utilize a form of the least mean square (LMS) algorithms. In the active control of noise, it is common practice to locate an error microphone far from the control source to avoid the near-field effects by evanescent waves. Such a distance between the control source and the error microphone makes a certain level of time-delay inevitable and, hence, may yield undesirable effects on the convergence properties of control algorithms such as filtered-x LMS. This paper discusses the dependence of the convergence rate on the acoustic error path in these popularalgorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. Performances of the new LMS algorithms are presented in comparison with those by the conventional algorithms based on computer simulations and experiments.