• Journal of Institute of Control, Robotics and Systems
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• v.22 no.3
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• pp.210-216
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• 2016

This paper presents a novel collision avoidance technique for mobile robots based on omni-directional vision simultaneous localization and mapping (SLAM). This method estimates the avoidance path and speed of a robot from the location of an obstacle, which can be detected using the Lucas-Kanade Optical Flow in images obtained through fish-eye cameras mounted on the robots. The conventional methods suggest avoidance paths by constructing an arbitrary force field around the obstacle found in the complete map obtained through the SLAM. Robots can also avoid obstacles by using the speed command based on the robot modeling and curved movement path of the robot. The recent research has been improved by optimizing the algorithm for the actual robot. However, research related to a robot using omni-directional vision SLAM to acquire around information at once has been comparatively less studied. The robot with the proposed algorithm avoids obstacles according to the estimated avoidance path based on the map obtained through an omni-directional vision SLAM using a fisheye image, and returns to the original path. In particular, it avoids the obstacles with various speed and direction using acceleration components based on motion information obtained by analyzing around the obstacles. The experimental results confirm the reliability of an avoidance algorithm through comparison between position obtained by the proposed algorithm and the real position collected while avoiding the obstacles.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.7
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• pp.700-710
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• 2009

A computer vision technique of estimating the location of an unmanned ground vehicle is proposed. Identifying the location of the unmaned vehicle is very important task for automatic navigation of the vehicle. Conventional positioning sensors may fail to work properly in some real situations due to internal and external interferences. Given a DSM(Digital Surface Map), location of the vehicle can be estimated by the registration of the DSM and multiview range images obtained at the vehicle. Registration of the DSM and range images yields the 3D transformation from the coordinates of the range sensor to the reference coordinates of the DSM. To estimate the vehicle position, we first register a range image to the DSM coarsely and then refine the result. For coarse registration, we employ a fast random sample matching method. After the initial position is estimated and refined, all subsequent range images are registered by applying a pair-wise registration technique between range images. To reduce the accumulation error of pair-wise registration, we periodically refine the registration between range images and the DSM. Virtual environment is established to perform several experiments using a virtual vehicle. Range images are created based on the DSM by modeling a real 3D sensor. The vehicle moves along three different path while acquiring range images. Experimental results show that registration error is about under 1.3m in average.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.27-32
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• 2005

DEM is needed for urban modeling, forecasting of floods and the analysis of slope and aspect. It has been generated using digital maps, aerial photos or satellite imageries. Recently, however, many studies on DEM generation from LiDAR data has been conducted because of its efficiency and accuracy. Filtering is said to be the process of making DEM by eliminating non-ground points from LiDAR data. In most researches, some input parameters such as the size of filter are required. The purpose of this investigation is to automatically obtain DEM by eliminating objects of various sizes without the knowledge of the objects' sizes. The experimental results show that most of objects on steep terrain are eliminated by the proposed method.

• Fashion & Textile Research Journal
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• v.18 no.4
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• pp.457-467
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• 2016

This study aimed to develop functional underwear for elderly women in their sixties in terms of good fit, wear comfort and body temperature regulation. To satisfy elderly women's physical and metabolical needs, an automatic temperature control system via PCM treatment was applied. Underwear pattern was produced by producing body surface replica, which was derived from 3D body parametric model. Differential ratios of outline length and area between 3D surface and 2D plane were 1.4% and 0.5%, respectively. The reduction rate was determined as 10% through the expert's evaluation. PCM treated fabric showed higher Q-max, meaning that it can facilitate the thermal transition in hot situation. Moreover, it also showed higher insulation to preserve heat and keep warm microclimate in a cold weather. Heat distribution measurements on various body parts revealed that the temperature after PCM treatment was significantly higher. The clothing pressure after 10% pattern reduction showed higher before reduction, at the same time, even lower than the comfort clothing pressure range of $5{\sim}10gf/cm^2$, implying that experimental garment of this research is acceptable in terms of clothing pressure. Evaluation results on the comfort to move in various motions proved that adequate clothing pressure improved the wear comfort in various motions.

• Fashion & Textile Research Journal
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• v.9 no.4
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• pp.418-424
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• 2007

The purpose of this study is to propose a standard of converting 3D shape of men in twenties to 2D patterns. This can be a basis for scientific and automatic pattern making for high quality custom clothes. Firstly, representative 3D body shape of men was modeled. Then the 3D model was divided into 3 shells, front, side and back. Among them, the front shell was divided into 4 blocks by bust line and princess line. Secondly, curves are generated on each block according to matrix combination by grid method. Then triangles were developed into 2D pieces by reflecting the 3D curve length. The grid was arranged to maintain outer curve length. Next, the area of developed pieces and block were calculated and difference ratio between the block area and the developed pieces' area is calculated. Also, area difference ratio by the number of triangles is calculated. The difference ratio was represented as graphs and optimal section is selected by the shape of graphs. The optimal matrix was set considering connection with other blocks. Curves of torso upper front shell were regenerated by the optimal matrix and developed into pieces. We validated it's suitability by comparing difference ratio between the block area and the developed pieces' area of optimal section. The results showed that there was no significant difference between block area and the pieces' area developed by optimal matrix. The optimal matrix for 2D developing could be characterized as two types according to block's shape characteristics, one is affected by triangle number, the other is affected by number of raws more than columns. Through this study, both the 2D pattern developing from 3D body shape and 3D modeling from 2D pattern is possible, so it's standardization also possible.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.8
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• pp.3567-3582
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• 2020

Human activities are often affected by weather conditions. Automatic weather recognition is meaningful to traffic alerting, driving assistance, and intelligent traffic. With the boost of deep learning and AI, deep convolutional neural networks (CNN) are utilized to identify weather situations. In this paper, a three-channel convolutional neural network (3C-CNN) model is proposed on the basis of ResNet50.The model extracts global weather features from the whole image through the ResNet50 branch, and extracts the sky and ground features from the top and bottom regions by two CNN5 branches. Then the global features and the local features are merged by the Concat function. Finally, the weather image is classified by Softmax classifier and the identification result is output. In addition, a medium-scale dataset containing 6,185 outdoor weather images named WeatherDataset-6 is established. 3C-CNN is used to train and test both on the Two-class Weather Images and WeatherDataset-6. The experimental results show that 3C-CNN achieves best on both datasets, with the average recognition accuracy up to 94.35% and 95.81% respectively, which is superior to other classic convolutional neural networks such as AlexNet, VGG16, and ResNet50. It is prospected that our method can also work well for images taken at night with further improvement.

• International Journal of CAD/CAM
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• v.6 no.1
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• pp.41-48
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• 2006

Nowadays major shipbuilding companies are trying to expand their business not only to shipbuilding but to offshore projects as well. DSME is one of them. DSME is trying to set up a flexible design and construction environment for shipbuilding and offshore construction in a single shipyard. The shipbuilding and offshore projects, however, have their unique technology but they need to be designed and constructed in one site. To support this new requirement, DSME has developed an integrated CAD system for ship and offshore projects. In this integrated design environment, the designers can design commercial ships and offshore projects in a flexible manner. Concurrent design is very important for ship and offshore design. As compared to the complexity of the product, the design period is quite short. In effect, the design system for the ship and offshore project has to support concurrent design. One essential point of concurrent design environment is a product model based design system. DSME has developed and implemented the 3D product model concurrent design environment based on Tribon M3. Tribon is a widely used CAD system in shipbuilding area that is developed by Tribon Solutions. DSME has both customized the Tribon system and developed in-house application systems to support its own design and production procedures. All the design objects are modeled in one common database to support concurrent design and accurate production. The major in-house development focused on the modeling automation and automatic drawing generation. During the drawing generation process many of the additional production information are also extracted from the 3D product model. In addition, several applications and functionalities have been developed to apply the shipbuilding based Tribon M3 system to offshore projects. The development of shape nesting, tubular connection, isometric drawing, grating nesting systems are the typical.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.187-196
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• 2014

In this paper, Minimize driving energy for operation within a defined distance yeokgan fixed time-resolved and determine the nature of the train is traveling, and to model mathematically. Urban rail car cruise in general by the PID controller is used instead of automatically tracking a target value while traveling in energy consumption to be minimized by using optimal control model railroad charyangreul was designed under real operating conditions the same. The actual track conditions apply to the minimum value or a separate listing of cars around the track facility without a driving energy of the automatic operation and to reduce the driving energy. Therefore, actual route chosen straight line 8 / gradient segment / curve for the measured data analysis, such as sections within the city-minute drive each section and presented how the trains to save energy, depending on the pattern of the train station in the region.

• Advances in Computational Design
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• v.5 no.2
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• pp.127-146
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• 2020

Building Information Modeling (BIM) is increasingly used throughout the facility's life cycle for various applications, such as design, construction, facility management, and maintenance. For existing buildings, the geometry of as-built BIM is often constructed using dense, three dimensional (3D) point clouds data obtained with laser scanners. Traditionally, as-built BIM systems do not contain the material and textural information of the buildings' elements. This paper presents a semi-automatic method for generation of material and texture rich as-built BIM. The method captures and integrates material and textural information of building elements into as-built BIM using thermal infrared sensing (TIS). The proposed method uses TIS to capture thermal images of the interior walls of an existing building. These images are then processed to extract the interior walls using a segmentation algorithm. The digital numbers in the resulted images are then transformed into radiance values that represent the emitted thermal infrared radiation. Machine learning techniques are then applied to build a correlation between the radiance values and the material type in each image. The radiance values were used to extract textural information from the images. The extracted textural and material information are then robustly integrated into the as-built BIM providing the data needed for the assessment of building conditions in general including energy efficiency, among others.

• Journal of Korea Multimedia Society
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• v.6 no.6
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• pp.1088-1099
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• 2003

The syntax-directed translation using semantic actions is frequently used in construction of compiler for text programming languages. it is very useful for the language designers to develop compiler back-end using a syntax structure of a source programming language. Due to the lack of the integrated representation method for a parse tree node and modeling method of syntax structures, it is very hard to construct compiler using syntax-directed translation in visual languages. In this Paper, we propose a visual language compiler generation method for constructing a visual languages compiler automatically, using syntax-directed translation. Our method uses the Picture Layout Grammar as a underlying grammar formalism. This grammar allows our approach to generate parser efficiently u sing And-Or-Waiting Graph and encapsulating syntax definition as one unit. Unlike other systems, we suggest separating the specification and the generation of semantic actions. Because of this, it provides a very efficient method for modification.