• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.111-124
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• 2011

The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight by opening/closing of a blind. In previous researches on blind controls, major problem is that the time interval and amount of blind movement do not meet the control objective at the inflected zone of solar profile curve. To overcome these limitations revealed in theprevious researches, following tasks were performed in this study. i)To establish the control objective to accomplish the goal of this study. ii)To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various solar profile angle curves. This study proposed the control strategy and method that define the base control section implying the inflection point within the control objective zone and subsequently, divide the control sections for the residual time zones. The proposed strategy and method are found to increase the incoming daylight and solar irradiation by 0 to 15 %.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.12 s.105
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• pp.1378-1388
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• 2005

Spatial control of sound is essential to deliver better sound to the listener's position in space. As it can be experienced in many listening environments. the quality of sound can not be manifested over every Position in a hall. This motivates us to control sound in a region we select. The primary focus of the developed method has to do with the brightness and contrast of acoustic image in space. In particular, the acoustic brightness control seeks a way to increase loudness of sound over a chosen area, and the contrast control aims to enhance loudness difference between two neighboring regions. This enables us to make two different kinds of zone - the zone of quiet and the zone of loud sound - at the same time. The other perspective of this study is on the direction of sound. It is shown that we can control the direction of perceived sound source by focusing acoustic energy in wavenumber domain. To begin with, the proposed approaches are formulated for pure-tone case. Then the control methods are extended to a more general case, where the excitation signal has broadband spectrum. In order to control the broadband signal in time domain, an inverse filter design problem is defined and solved in frequency domain. Numerical and experimental results obtained in various conditions certainly validate that the acoustic brightness, acoustic contrast, direction of wave front can be manipulated for some finite region in space and time.

• The korean journal of orthodontics
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• v.22 no.2 s.37
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• pp.309-325
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• 1992

The purpose of this study was to evaluate the effect of intrinsic factor and extrinsic factor for growth of the mandibular condylar cartilage of 4 day-old rats in a serum-free medium for 1, 4, 7, 14 days. They were compared with normal growth in vivo and with growth of spheno-occipital synchondrosis in serum-free medium. The cellular kinetics of cartilages were evaluated by auto-radiography of tritiated thymidine. 1. Condylar cartilage was enlarged with rounded head on day 14 of experiment while in vivo the rounded-headed shape changed into functionally flattened appearance. 2. On day 14 of experiment, a severe reduction of the proliferative zone and a considerable increase of the hypertrophic zone were observed while in normal control group endochondrol bone formation and bone marrow were observed. 3. The proliferative activity in the proliferative zone of condylar cartilage detected by $^3H-thymidine$ incorporation was lower than that of normal control group and decreased more than that of spheno-occipital synchondrosis, but it continued during the 14 days of culture. 4. The continued maintenance of condylar cartilage and morphologic change were disturbed in this culture system, but cell division within the proliferative zone was continued and probably linked to intrinsic factor.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.8
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• pp.743-748
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• 2007

Recently, various types of camera mouse are developed using the image processing. The camera mouse showed limited performance compared to the traditional optical mouse in terms of the response time and the usability. These problems are caused by the mismatch between the size of the monitor and that of the active pixel area of the CMOS Image Sensor. To overcome these limitations, we designed a new input device that uses the face recognition as well as the speech recognition simultaneously. In the proposed system, the area of the monitor is partitioned into 'n' zones. The face recognition is performed using the web-camera, so that the mouse pointer follows the movement of the face of the user in a particular zone. The user can switch the zone by speaking the name of the zone. The multimodal mouse is analyzed using the Keystroke Level Model and the initial experiments was performed to evaluate the feasibility and the performance of the proposed system.

• Journal of the Korean Solar Energy Society
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• v.31 no.4
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• pp.1-8
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• 2011

In this paper, inverse building modeling was applied to building perimeter zones which have different window orientation. Two test zones of east-facing and west-facing zones in ERS(Energy Resource Station) building, which is representative of small commercial building, was used to test performance of cooling load calculation and peak cooling load reduction. The dynamic thermal load model for the east and west zone was validated using measured data for the zones and then it was used to investigate the effect of peak cooling load reduction by adjustment of indoor cooling temperature set points during on-peak time period. For the east zone, the peak load can be reduced to about 60% of the peak load for conventional control even without any precooling. For the west zone, PLR is nearly independent of the start of the on-peak period until a start time of 1pm. Furthermore, PLR has a small dependence on the precooling duration. Without any precooling, the peak cooling load can be reduced to about 35% of the peak load associated with conventional control.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.2
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• pp.106-114
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• 2024

In the 21st century, the rapid development of automation and artificial intelligence technologies is driving innovative changes in various industrial sectors. In the transportation industry, this is evident with the commercialization of autonomous vehicles. Moreover research into autonomous navigation technologies is actively underway in the aviation and maritime sectors. Consequently, for the practical implementation of autonomous ships, an effective collision avoidance algorithm has become a crucial element. Therefore, this study proposes a collision avoidance algorithm based on the Obstacle Zone by Target(OZT), which visually represents areas with a high likelihood of collisions with other ships or obstacles. The A-star algorithm was utilized to represent obstacles on a grid and assess collision risks. Subsequently, a collision avoidance algorithm was developed that performs fuzzy control based on calculated waypoints, allowing the vessel to return to its original course after avoiding the collision. Finally, the validity of the proposed algorithm was verified through collision avoidance simulations in various encounter scenarios.

• The Journal of the Acoustical Society of Korea
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• v.35 no.3
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• pp.216-222
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• 2016

Generation of a quiet zone in noisy environment is undoubtedly of considerable realistic significance. This paper describes development and implementation of a multichannel real-time active noise control (ANC) system for 3 dimensional noisy environment to enhance the quiet zone performance in terms of size and noise cancellation gain. The proposed ANC system employes a multichannel delay-compensated filtered-X least mean square (FXLMS) algorithm; its real-time implementation is designed in TMS320C6713 digital signal processor (DSP) board. The system is evaluated for cancelling various tonal frequency noises in the range from 100 to 500 Hz, and the performance is then illustrated by measuring the quiet zone in terms of sound pressure level (SPL) attenuation. Experiment results show that a quiet zone of quiet with satisfactory size and maximum 24 dB noise attenuation is successfully generated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.189-194
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• 2007

Recently, as consumer's claim fur car safety is increased, quality inspection method fur welding zone is strengthened. Therefore, from the methods that depend on welding zone bead shape size of seat frame in macrography or passive examination, the quality control by whole recording inspection is required. In this study, the system that is measuring automatically if worker checks welding bead fur quality inspection of seat frame is developed using LabVIEW. If the quality standard for the bead width and length of welding zone is inputted, the system measures automatically whether welding zone is bead length or bead width. Measured data is preserved by points and quality recording of welding zone is stored. The car seat きme welding zone is applied and experimented. The results gave good influence o9 the quality control of work efficiency.

• Journal of the Korean Institute of Educational Facilities
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• v.22 no.2
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• pp.3-13
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• 2015

The policy of the Ministry of education through the social awareness and issues are being changed. Accordingly, in response to the school building which also has to be changed. This study is Low-floor(1~2 floor) for high accessibility, important management and a lot of locomotion. This study is analysis by floor of newly established schools in Chungbuk. Facility and space on the possible low-floor situated are classified administrative zone, health zone, student support + local exchange zone, STEAM(creativity, personality) supporting zone. The administrative area includes administration office, principal's office and board rooms. The administrative zone is located against schoolyard. Because it is possible visual control of schoolyard. also it controls visitor access so it is placed near main entrance. Health zone is located near a special class, counseling center and wee class for emergency situation. and is located near schoolyard for visual control. Student support + local exchange area includes library and computer lab, audio-visual room, auditorium or gymnasium. It put more emphasis resident welfare, culture and education. So it opens for local residents. It is located center of few stories or near entrance. STEAM(creativity, personality) supports science lab, art room, family room. It is possible such a theory class, experience class and indoor and outdoor class. It is located few floors. This study is used as a reference for school building projects planing.

• Journal of the Korean Solar Energy Society
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• v.32 no.5
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• pp.31-40
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• 2012

This paper introduces a methodology for NREL 5MW wind turbine, which is the variable speed and variable pitch(VSVP) control system. This control strategy maximizes the power extraction capability from the wind in the low wind speed region and regulates the wind turbine power as the rated one for the high wind speed region. Also, pitch control efficiency is raised by using pitch scheduling.Torque schedule is made of torque table depending on the rotor speed. Torque control is used for vertical region in a torque-rotor speed chart. In addition to these, mechanical loads reduction using a drive train damper and exclusion zone on a torque schedule is tried. The NREL 5MW wind turbine control strategy is comprised by the generator torque and blade pitch control. Finally, proposed control system is verified through GH Bladed simulation.