• KIEAE Journal
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• v.12 no.6
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• pp.123-128
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• 2012

A window increases the lighting quality of a space by allowing daylight into the space, and maintains visual contact with the outside. Moreover, the window with a preferred view provides many benefits such as psychological satisfaction, occupants' health and improved environmental quality. This study aimed to investigate how view elements and window luminance influence occupants' seating preference in a living room. The experiment was carried out in a mock-up model with thirty-two subjects (17 men and 15 women). The nine seating positions in a living room have different view such as natural view (trees or sky) and man-made view (paving and roof top). Subjects were asked to select a position in the room where they felt most visual comfort. Simultaneously Photolux 2.1 software was used to analyze the window luminance. The experiment results indicated that subjects prefer to be seated near a window and feel comfort in a seating overlooking the trees and sky. This would indicate that the natural elements of the view and a distance to the window affect seating preference to the occupants.

• The KIPS Transactions:PartC
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• v.12C no.4 s.100
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• pp.571-580
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• 2005

In fast long-distance networks, TCP's congestion control algorithm has the problem of utilizing bandwidth effectively. Several window-based congestion control protocols for high-speed and large delay networks have been proposed to solve this problem. These protocols deliberate mainly three properties : scalability, TCP-friendliness, and RTT-fairness. These protocols, however, cannot satisfy above three properties at the same time because of the trade-off among them This paper presents a new window-based congestion control algorithm, called EM (Exponential Increase/ Multiplicative Decrease), that simultaneously supports all four properties including fast convergence, which is another important constraint for fast long-distance networks; it can support scalability by increasing congestion window exponentially proportional to the time elapsed since a packet loss; it can support RTT-fairness and TCP-friendliness by considering RTT in its response function; it can support last fair-share convergence by increasing congestion window inversely proportional to the congestion window just before packet loss. We evaluate the performance of EIMD and other algorithms by extensive computer simulations.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.164-164
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• 2000

This paper proposes a moving window technique that extracts lanes and vehicles using the images captured by a CCD camera equipped inside an automobile in real time. For the purpose, first of all the optimal size of moving window is determined based upon speed of the vehicle, road curvature, and camera parameters. Within the moving windows that are dynamically changing, lanes and vehicles are extracted, and the vehicles within the driving lanes are classified as obstacles. Assuming highway driving, there are two sorts of image-objects within the driving lanes: one is ground mark to show the limit speed or some information for driving, and the other is the vehicle as an obstacle. Using characteristics of three-dimension objects, a neural network can be trained to distinguish the vehicle from ground mark. When it is recognized as an obstacle, the distance from the camera to the front vehicle can be calculated with the aids of database that keeps the models of automobiles on the highway. The correctness of this measurement is verified through the experiments comparing with the radar and laser sensor data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.568-574
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• 2012

Turbulent boundary layer noise is already a significant contributor to sonar self noise. For developing acoustic window of sonar system to reduce self noise, a parametric study of design factors of acoustic window is presented. Distance of sensor array from acoustic window, material and damping layer are studied as design factors to influence in the characteristics of the transfer function of self noise. As the result these design factors make change the characteristics of transfer function slightly. Among design factors the location of sensor array is most important parameter in the self noise reduction.

• Journal of IKEEE
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• v.23 no.2
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• pp.395-402
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• 2019

In this paper, we implemented an Ultra-Wideband radar system using Stripmap Synthetic Apertrure Radar algorithm to recognize objects inside a box. Different window functions such as Hanning, Hamming, Kaiser, and Taylor functions to improve image recognition performance are applied and implemented to radar system. The Ultra-Wideband radar system with 3.1~4.8 GHz broadband and UWB antenna were implemented to recognize the conductor plate located inside 1m3 box. To obtain the image, we use the propagation data in the time domain according to the 1m movement distance and use the Range Doppler algorithm. The effect of different window functions to improve the recognition performance of the image are analyzed. From the compared results, we confirmed that the Kaiser window function can obtain a relatively good image.

• Journal of Environmental Health Sciences
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• v.44 no.4
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• pp.360-369
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• 2018

Objectives: Outdoor tobacco smoke can penetrate into the indoor environment through cracks in the building envelope. This study aimed to characterize the particle size distribution of infiltrated secondhand smoke (SHS) through the gap in a single glazed and a secondary glazed window according to pressure differences in a chamber. Methods: Two polyvinyl chloride sliding windows were evaluated for infiltration, one with a glazed window and the other with a secondary glazed window. Each window was mounted and sealed in a polycarbonate chamber. The air in the chamber was discharged to the outside to establish pressure differences in the chamber (${\Delta}P$). Outdoor smoking sources were simulated at a one-meter distance from the window side of the chamber. The particle size distribution of the infiltrated SHS was measured in the chamber using a portable aerosol spectrometer. The particle size distribution of SHS inside the chamber was normalized by the outdoor peak for fine particles. Results: The particle size distribution of SHS inside the chamber was similar regardless of window type and ${\Delta}P$. It peaked at $0.2-0.3{\mu}m$. Increases in particulate matter (PM) concentrations from SHS infiltration were higher with the glazed window than with the secondary glazed window. PM concentrations of less than $1{\mu}m$ increased as ${\Delta}P$ was increased inside the chamber. Conclusions: The majority of infiltrated SHS particles through window gap was $0.2-0.3{\mu}m$ in size. Outdoor SHS particles infiltrated more with a glazed window than with a secondary glazed window. Particle sizes of less than $1{\mu}m$ were associated with ${\Delta}P$. These findings can be a reference for further research on the measurement of infiltrated SHS in buildings.

• KIEAE Journal
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• v.10 no.2
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• pp.25-30
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• 2010

The daylited space can improve visual comfort and occupant's well-being. However discomfort glare from the daylight is a common problem in indoor environments and in general, the window is the main glare sources. Some formulas have been proposed for predicting glare from the daylight, however, they do not consider the effect on glare of the view through a window and some studies proved that they are inadequate in real daylight situation. This research aims to identify the relationship between view and discomfort glare considering the subjective impressions. As a preliminary experiment, this paper sets up the experimental protocol to reveal relationships between views from a window and visual perception in a controlled laboratory experiment. $1.2m{\times}1.2m$ artificial window was developed and $0.9m{\times}0.9m$ view image was placed on the window. Discomfort glare and impression evaluation was carried out under four different views and one blank view as a reference condition. The results showed that the subjects evaluated discomfort glare differently with the views even under the same luminance conditions and tended to feel less glare with distance views compared to near views.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.8B
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• pp.473-481
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• 2007

We are interested in the PON which is easy to install and inexpensive to maintain, as it is a solution of the FTTH that is a core technology of the BcN access network. When a new ONU is connected, TDMA PON has a procedure called ranging that OLT measures the distance and allocates the equalized delay to it in order to provide the same logical distance to all ONUs. For the procedure, the OLT has to open a time window several times and already activated ONUs cannot transmit a data to the upstream during the periods. Accordingly, it is important to reduce the window size for saving the bandwidth and providing a user the service smoothly. In this paper, we investigate the ONU activation method of G-PON based on ITU-T G984.3 and suggest an advanced method(algorithm I) that minimizes the window size without information of ONU distance. The size can be reduced by calculating the pre-assigned delay obtained during Serial number state. Also, we compare it with another(algorithm II) with information of distance. As a result, the window size reduces to $50{\sim}90%$ for the algorithm I and 99% for algorithm II during the ONU activation process.

• Korean Journal of Cognitive Science
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• v.20 no.4
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• pp.573-601
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• 2009

The present study investigated the perceptual span during reading Korean, using the moving-window display change technique introduced by McConkie and Rayner(1975). Eight different window sizes were used in Experiment 1. They were 3, 5, 7, 9, 11, 13, 15 characters in size and the full line. Reading rate, number of fixation, saccadic distance, fixation duration were compared between each window-size condition and the full line condition. The reading rate was no higher in the full line condition than in the 15 character condition but was higher than in the other conditions. The number of fixations was no larger in the full line condition than in the 15 character condition, had a tendency to be larger than in the 13 characters condition, and was more than in the other conditions. The result pattern of the saccadic distance based on character was the same as that of the reading rate, and the saccadic distance based on the pixel was the same as that of the number of fixation. Similarly, for fixation duration, there was no differences between whole line condition and 15, 13, and 11 characters condition. The fixation duration had a tendency to be shorter in the 9 characters, and was shorter in the 7, 5, and 3 characters conditions than whole line condition. In Experiment 2, based on asymmetry of perceptual span, the 6 different window sizes(0, 1, 2, 3, 4 characters in size and the full line) were used. There was a difference only between the 0 condition and the other conditions in the reading rate, number of fixations, fixation duration. Considering the pattern of eye-movement measures above, the perceptual span of Korean readers extends about 6-7 characters to the right of fixation and 1 character to the left of fixation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.1
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• pp.56-64
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• 2013

Turbulent boundary layer noise is already a significant contributor to sonar self noise. For developing acoustic window of sonar system to reduce self noise, a parametric study of design factors of acoustic window is presented. Distance of sensor array from acoustic window, materials of acoustic window and characteristics of damping layer are studied as design factors to influence in the characteristics of the transfer function of self noise. As the result, these design factors make change the characteristics of transfer function slightly. Among design factors the location of sensor array is most important parameter in the self noise reduction