• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.9
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• pp.1102-1107
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• 1988

We describe a volume holographic associative memory using photorefractive material and conventional planar mirror. Multiple hologram is generated with two angular multiplexed writing beams and Fourier transformed object beam in Ba Ti O3 crystal at 0.6328 um. Complete image can be recalled successfully by partial input of the original stored image without any additional thresholding and optical feedback process. It is proved that our system is useful for optical implementation of real-time associative memory and location addressable memory.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.1-10
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• 2012

In this paper, we propose a new class of color histogram model suitable for object tracking. In addition to the pixel count, each bin of the proposed model also contains the spatial mean and the average value of the pixels located at a certain distance from the mean location of the bin. Using the proposed color histogram model, we derive a mean shift procedure using the modified Bhattacharyya distance. Unlike most mean shift based methods, our algorithm performs well even when the object being tracked shares similar colors with the background. Experimental results demonstrate improved tracking performance over existing methods.

• The KIPS Transactions:PartD
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• v.10D no.7
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• pp.1077-1088
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• 2003

To increase the retrieval performance in spatial database systems, it is required to develop spatial indexing methods considered the spatial locality. The spatial locality is related to the location property of objects. The previous spatial indexing methods are not considered the circular location property that objects will be taken. In this paper, we propose a dynamic spatial index structure called $Cr^*$-tree, and evaluate the performance of the proposed index structure. This is a new spatial index structure considered the circular location property of objects in which a search space is constructed with the circular and linear domains. By the simulation results, the $Cr^*$-tree shows that the number of disk across is low and the bucket utilization is high regardless of object distribution and bucket capacity.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.7
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• pp.1314-1320
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• 2008

Recently, LBS(Location Based Service) which provides useful service based on the location of objects or human has drawn the attention of the research community. To provide LBS, many researchers have proposed many localization systems such as Cricket or Ubisense, however, these systems have the limit that it is very hard to perform the complicated computation on these systems because these systems consist of sensor nodes which have very limited computing power. In the paper, we propose a new localization system with the gateway node which has very high computing power and resource which is suitable for the complicated computation needed for localization.

• Journal of the Korea Society of Computer and Information
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• v.15 no.1
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• pp.83-90
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• 2010

The number of searched nodes and the computation time in an index should be minimized for optimizing the processing cost of the nearest neighbor query. The Measurement of search distance considered a circular location property of objects is required to accurately select the nodes which will be searched in the nearest neighbor query. In this paper, we propose the processing method of the nearest neighbor query be considered a circular location property of object where the search space consists of a circular domain and show its performance by experiments. The proposed method uses the circular minimum distance and the circular optimal distance which are the search measurements for optimizing the processing cost of the nearest neighbor query.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1555-1565
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• 2010

This paper presents a new method for indentifying the location of impact source in a buried duct. In a gas pipeline, the problem of leakage occurs due to the mechanical load exerted by construction equipment. Such leakage can cause catastrophic disasters in gas supply industries. Generally, the cross-correlation method has been used for indentifying the location of impact source in a pipeline. Since this method involves the use of the dispersive acoustic wave, it derives an amount of error in process of estimating the time delay between acoustic sensors. The object of this paper is to estimate the time delay in the arrival of the direct wave by using the wavelet transform instead of the dispersive wave. The wavelet transform based method gives more accurate estimates of the impact location than the cross-correlation method does. This method is successfully used to identify the location of impact force in an actual buried gas duct.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.1832-1843
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• 1995

Tool interference is one of the most critical problems in sculptured surface machining. When machining cavities and concaves, the tool frequently overcuts the portions of the surface, which cause inaccuracy in machining. So tool interference-free paths must be generated for rough cutting more efficiently. In this paper a software using SSI(Surface/Surface intersection) algorithm is developed for eliminating tool interference which occurs in an offset surface in 3-dimensional free form surface modeling. this work consists of two stages : using the offset data, the intersection curves are rapidly checked by this algorithm at the first stage. CL(cutter location) data are obtained by deleting the loop section of intersected offset patches at the second stage. This algorithm can reduce the amount of memory required to store machining data and also easily check region which have the possibility of intersection. Also, This software is verified to be useful in machining a curved object on a DNC milling machine.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2480-2484
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• 2005

Electrical resistance tomograpy (ERT) maps resistivity values of the soil subsurface and characterizes buried objects. The characterization includes location, size, and resistivity of buried objects. In this paper, truncated least squares (TLS) is presented for the solution of the ERT image reconstruction. Results of numerical experiments in ERT solved by the TLS approach is presented and compared to that obtained by the Gauss-Newton method.

• Proceedings of the KSR Conference
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• 1999.05a
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• pp.33-40
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• 1999

Park and Ride(P＆R) system has not implemented it's intended object in Seoul metropolitan area, still less it didn't impact on diminishing the ridership of urban railway. This paper is focused on analysis of Park and Rail ride user survey of travel behavior and trip chain. We propose the ideal location of P＆R in Seoul and stratagies to increase the utilization of P＆R.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.7
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• pp.1726-1748
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• 2024

Trajectory planning is vital for autonomous systems like robotics and UAVs, as it determines optimal, safe paths considering physical limitations, environmental factors, and agent interactions. Recent advancements in trajectory planning and future location prediction stem from rapid progress in machine learning and optimization algorithms. In this paper, we proposed a novel framework for Spatial-temporal transformer-based feed-forward neural networks (STTFFNs). From the traffic flow local area point of view, skip-gram model is trained on trajectory data to generate embeddings that capture the high-level features of different trajectories. These embeddings can then be used as input to a transformer-based trajectory planning model, which can generate trajectories for new objects based on the embeddings of similar trajectories in the training data. In the next step, distant regions, we embedded feedforward network is responsible for generating the distant trajectories by taking as input a set of features that represent the object's current state and historical data. One advantage of using feedforward networks for distant trajectory planning is their ability to capture long-term dependencies in the data. In the final step of forecasting for future locations, the encoder and decoder are crucial parts of the proposed technique. Spatial destinations are encoded utilizing location-based social networks(LBSN) based on visiting semantic locations. The model has been specially trained to forecast future locations using precise longitude and latitude values. Following rigorous testing on two real-world datasets, Porto and Manhattan, it was discovered that the model outperformed a prediction accuracy of 8.7% previous state-of-the-art methods.