• IEMEK Journal of Embedded Systems and Applications
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• v.3 no.2
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• pp.109-118
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• 2008

We present a robust localization algorithm using particle filter for mobile robots in a dynamic environment. It is difficult to describe moving obstacles like people or other robots on the map and the environment is changed after mapping. A mobile robot cannot estimate its pose robustly with this incomplete map because sensor observations are corrupted by un-modeled obstacles. The proposed algorithms provide robustness in such a dynamic environment by suppressing the effect of corrupted sensor observations with a selective update or a sampling from non-corrupted window. A selective update method makes some particles keep track of the robot, not affected by the corrupted observation. In a sampling from non-corrupted window method, particles are always sampled from several particle sets which use only non-corrupted observation. The robustness of proposed algorithm is validated with experiments and simulations.

• Journal of The Korean Digital Architecture Interior Association
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• v.8 no.1
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• pp.57-64
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• 2008

There are many problems in present truss-deck slab system for example welding defect, segregation, water leakage, rust and tarnish etc. These problems may be caused by spot welding thin galvanized steel plate and lattice bar. The TOX Joining Systems is to join metal sheets of different material and thickness with and without coating or painting without adding heat or a joining part. Newly developed TOX-deck slab system using non-welding joint is free from above mentioned problems. The objects of this study are suggestion of design strength of TOX joint by experimental and statistical analyses and development of window based program to design the TOX-deck slab system.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.4
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• pp.251-257
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• 2015

In ultrasonic nonlinear parameter measurement using the fast Fourier transform(FFT) of tone-burst signals, the side lobe and leakage on spectrum because of finite time and non-periodicity of signals makes it difficult to measure the harmonic magnitudes accurately. The window function made it possible to resolve this problem. In this study, the effect of the Hanning and Turkey window functions on the experimental measurement of nonlinear parameters was analyzed. In addition, the effect of changes in tone burst signal number with changes in the window function on the experimental measurement was analyzed. The result for both window functions were similar and showed that they enabled reliable nonlinear parameter measurement. However, in order to restore original signal amplitude, the amplitude compensation coefficient should be considered for each window function. On a separate note, the larger number of tone bursts was advantageous for stable nonlinear parameter measurement, but this effect was more advantageous in the case of the Hanning window than the Tukey window.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.23-29
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• 2008

It is necessary to develope the active safety system in terms of driver's safety and convenience. In this paper, we were developed the non-contact type of safety window system operated by the initial value of feedback control such as the output signal of photo sensor. It was designed based on the control algorithm with an improved load sensitivity. Therefore, compared with the existing system, it is possible to prevent the occurrence of a mull-function. Also, it has a convenient functions of the window such as an auto up/down and closing, and has a response times better. It can be installed the various types of common vehicles that have the different movement distance and speed of window. In conclusion, the developed system may be adapted the vehicle commercially.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.729-740
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• 2020

The study examines the efficiency of private sector banks in India with the help of Window DEA (Data Envelopment Analysis) for a period from 2005 to 2017. With a window of three years, the period was divided into 11 windows. The study outcomes show that 59.9% of all private sector banks in India operate at more than 0.9 level of efficiency, and there are only three occasions when banks were operating at the efficiency value between 0.6 to 0.7. Further, the consistency in the efficiency scores of the banks has also been analyzed using an efficiency mapping matrix, and the mean efficiency score of the bank in each window is studied. The score of standard deviation was interpreted accordingly for these banks. Banks that are showing the highest efficiency scores also have a higher variance of efficiency scores. There was no bank identified in the matrix that promises high-efficiency ratings with low variability. The study concludes that the analysis of the efficiency mapping matrix indicates that, as a DMU escalates in the efficiency scores, the standard deviation reflecting the risk in overall efficiency scores also tends to rise. The findings complement the concept of higher risk to higher return or greater efficiency.

• Korean Institute of Interior Design Journal
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• v.26 no.6
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• pp.33-41
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• 2017

Hanok in Bukchon was originally planned for residential buildings, but recently, there have been needs and wants to renovate and modernize the houses into some other purposes. Many researches exist with regard to hanok in Bukchon; yet, most previous studies focus on the spatial changes caused by the renovation of hanok. Only few studies have dealt with some component issues such as window. Nevertheless, window of hanok is an important aesthetic and functional element that determines unique characteristics of hanok. In the process of recent modernization and functional changes of hanok, its traditional design is also changing. In fact, Bukchon has been rapidly evolving for tourist attractions so that banok has been renovated in various commercial as well as cultural purposes. Many of residential hanok have been converted into other purposes such as cultural, commercial or non-residential facilities so that the role of windows should be changed accordingly. Analyzing windows of the renovated hanok in Bukchon, this study identifies changes in its types in accordance with the repurposing. It deals with windows of the non-residential hanok only. A total of 456 Bukchon hanok are included in the Bukchon Historical and Cultural Center in the Hanok Register of the Hanok Registration System, which was enforced in 2001. Although 381 out of 456 hanok have been repaired since 2001, only 68 non-resident Bukchon hanok of the repaired ones are selected and surveyed in this study.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.9
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• pp.1650-1657
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• 2007

In this paper, we propose an Overlapped Block and an Hanning Window to prevent a Block Discontinuity when we use an algorithm to eliminate ringing artifact which is based on a block structure. The algorithm to eliminate ringing artifact operates with a block structure and 24-RGB data and is based on a modified K-means algorithm. The proposed overlapped block method is piled up one on another per an half of the size of unit-block when an input image is split into several unit-blocks. Therefore, we define a data unit as the unit-block of the block size, $16{\times}16$ pixels. We reconstruct the processed data units into the original form of input image by using an isotropic form of Hanning Window. Finally, in order to evaluate the performance of the abovementioned algorithms, we compare three image, an input image with ringing artifact, an image result obtained by conventional method (non-overlapped), and an image result obtained the proposed method.

• Journal of radiological science and technology
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• v.45 no.2
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• pp.135-143
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• 2022

In SPECT image, scatter count is the cause of quantitative count error and image quality degradation. This study is to evaluate the accuracy of CT based SC(CTSC) and energy window based SC(EWSC) as the comparison with existing Non SC. SPECT/CT images were obtained after filling air in order to acquire a reference image without the influence of scatter count inside the Triple line insert phantom setting hot rod(^99mTc 74.0 MBq) in the middle and each SPECT/CT image was obtained each separately after filling water instead of air in order to derive the influence of scatter count under the same conditions. For EWSC, 9 sub-energy windows were set additionally in addition to main energy window(140 keV, 20%) and then, images were acquired at the same time and five types of EWSC including DPW(dual photo-peak window)10%, DEW(dual energy window)20%, TEW(triple energy window)10%, TEW5.0%, TEW2.5% were used. Under the condition without fluctuations in primary count, total count was measured by drawing volume of interest (VOI) in the images of the two conditions and then, the ratio of scatter count of total counts was calculated as percent scatter fraction(%SF) and the count error with image filled with water was evaluated with percent normalized mean-square error(%NMSE) based on the image filled with air. Based on the image filled with air, %SF of images filled with water to which each SC method was applied is non scatter correction(NSC) 37.44, DPW 27.41, DEW 21.84, TEW10% 19.60, TEW5% 17.02, TEW2.5% 14.68, CTSC 5.57 and the scatter counts were removed the most in CTSC and %NMSE is NSC 35.80, DPW 14.28, DEW 7.81, TEW10% 5.94, TEW5% 4.21, TEW2.5% 2.96, CTSC 0.35 and the error in CTSC was found to be the lowest. In SPECT/CT images, the application of each scatter correction method used in the experiment could improve the quantitative count error caused by the influence of scatter count. In particular, CTSC showed the lowest %NMSE(=0.35) compared to existing EWSC methods, enabling relatively accurate scatter correction.

• Management Science and Financial Engineering
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• v.4 no.2
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• pp.43-58
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• 1998

Packet switch is a key component in high speed digital networks. This paper investigates congestion phenomena in the packet switching with input buffers. For large value of switch size N, mathematical models have been developed to analyze asymptotic maximum switch throughput under nonuniform traffic. Simulation study has also been done for small values of finite N. The rapid convergence of the switch performance with finite switch size to asymptotic solutions implies that asymptotic analytical solutions approximate very closely to maximum throughputs for reasonably large but finite N. Numerical examples show that non-uniformity in traffic pattern could result in serious degradation in packet switch performance, while the maximum switch throughput is 0.586 when the traffic load is uniform over the output trunks. Window scheduling policy seems to work only when the traffic is relatively uniformly distributed. As traffic non-uniformity increases, the effect of window size on throughput is getting mediocre.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.2
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• pp.162-167
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• 2012

This paper describes the design of a high-performance unified SVM classifier circuit. The proposed circuit supports both linear and non-linear SVM classifications. In order to ensure efficient classification, a 48x96 or 64x64 sliding window with 20 window strides is used. We reduced the circuit size by sharing most of the resources required for both types of classification. We described the proposed unified SVM classifier circuit using the Verilog HDL and synthesized the gate-level circuit using 65nm standard cell library. The synthesized circuit consists of 661,261 gates, operates at the maximum operating frequency of 152 MHz and processes up to 33.8 640x480 image frames per second.