• KIEAE Journal
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• v.13 no.2
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• pp.3-12
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• 2013

Recently, New Han-ok is in prevail because it has many good qualities as a dwelling. But the New Han-ok dwellers' needs and satisfaction ratio on their houses are not investigated yet. So, surveys on satisfaction ratio for New Han-ok were carried out to know New Han-ok's existing conditions and inhabitant's responses on New Han-ok dwellings. Followings are results. 1) Dwellers response that it is cool in summer and it is cold in winter. So, design and construction method against cold is needed for New Han-ok. 2) Window is the most picking element of New Han-ok for house improvement. 3) Window opening is main control method for cooling in summer. Warming sources in winter are various such as electricity, gas, oil, wood, etc. 4) PVC window structure and glasses were used for New Han-ok's window system as well as wooden window structure and Han-gi. 5) Interviewees are generally satisfied with New Han-ok's exterior view and inner spaces. Almost no humidifier is used. These results could be used for improvement of Han-ok and basic material for New Han-ok design.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.481-488
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• 2018

This study suggest the improvement of the CFRP adhesive mixing ratio about acoustic window to enhance SONAR performance. The CFRP of submarine is produced by allocation an acoustic window zone by the beam width of SONAR sensors. During the sea trial, SONAR system's bearing and range accuracy data is not in tolerance due to debonding phenomenon on CFRP. The inappropriate mixing ratio of adhesives caused that peeling phenomenon occurred in the acoustic window part, which is the reason for the deterioration of SONAR sensors performance. The report includes explanation of test procedure of SONAR, root cause analysis, CFRP manufacturing procedure, laboratory tests results, and proof of the performance at the sea trial.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.685-688
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• 2009

On account of Indoor Air Quality(IAQ) deterioration by reason of high insulation and air tightness for energy saving, absence of energy efficiency ventilation system development that can be domestic existing window system, the cost increase and the energy addition loss by mechanical ventilation for IAQ improvement, the ventilation obligation making design standard was prepared by a social and technical background and the necessity. In this study, an optimized design and simulation Analysis of natural ventilation window system classified by Apartment type was evaluated by CFD Computational analysis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.244-245
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• 2019

Recently, a variety of window cleaning devices have been developed. There are, however, few cases of anticipated problems and countermeasures that may arise after these devices are installed. Therefore, in this study, the emergency condition was derived and the emergency scenario was derived for the rail-mounted cleaning device. Emergency scenarios and countermeasures derived from this study will be used for continuous improvement and supplementation of cleaning devices through prototyping and testing.

• KIEAE Journal
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• v.13 no.1
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• pp.75-81
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• 2013

The balcony of our apartment building consists of unique construction similar to double skin. It is announced broadly that double skin is very effective system in improvement of natural ventilation and indoor thermal environment, and outdoor sound protection. So, for the improvement of indoor climate and energy saving, many peoples studied about environmental performance of our balcony construction. This study focus on shaft box facade, special form of box window construction. It consists of a system of box window with continuous vertical shafts that extend over a number of stories to create a stack effect. Proto-type was decided by analyzing various types of exiting apartments. Shaft box type balcony was created by setting up shaft space at a part of balcony. Air flow and contribution of air temperature were simulated, performance of shaft box type balcony was compared with existing balcony. Finally, we confirmed that shaft box type balcony has many possibility for improvement of indoor environment.

• Design & Manufacturing
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• v.12 no.1
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• pp.26-30
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• 2018

The aluminum chassis drive gear manufacturing process improvement has been very effective in both technical and economic aspects. Technology for Shear mold design technology, mold material selection and processing technology, and press molding technology has improved greatly overall. In the meantime, it is necessary to clarify the causes of defects that occur frequently due to lack of technology, Based on this, it is meaningful that it has secured the ability to respond to new product development and molding in the future. By applying these technologies, we plan to expand not only the drive gear chassis, but also various types of press forming such as frame, handle, various fastening parts of system window. In addition, the ability to develop precision products in the future is expected to become a driving force in further enhancing the competitiveness of companies.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.265-268
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• 2010

There have been proposed two types of low bit rate vocoder upto now : One is MBE type using the spectrum modeling and another is CELP type using the hybrid coding method. CELP type vocoder has mainly studied between them. Specially, much of intensity is concentrated in CELP vocoder due to the emergence of Internet Phone and PCS in a domestic. In order to improve the speech quality in CELP vocoder, in this paper, we proposed a new spectrum analysis algorithm with variable window. In CELP vocoder, the spectrum of the synthesised speech signal is distorted because the fixed size windows is used for spectrum analysis. So we have measured the spectral leakage and in order to minimize the spectral leakage have adjusted the window size. Applying this method G.723.1 ACELP, we can get SD(Spectral Distortion) reduction 0.084(dB), residual energy reduction 6.3% and MOS(Mean Opinion Score) improvement 0.1.

• Journal of Information Processing Systems
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• v.2 no.1
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• pp.34-38
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• 2006

In the wireless network, TCP performs poorly because it was originally designed for wired networks and does not take into consideration wireless characteristics such as mobility, high-loss probability, and hidden-terminal problems. In particular, in the wireless multi-hop networks, a large congestion window increases the probability of contention and packet losses, and TCP performance is degraded severely as a result. So, it is necessary to limit the TCP congestion window size in order keep the probability of contention loss in the system to a minimum. In this paper, we propose a new scheme for determining the maximum congestion window size based on the measured bandwidth and Round-Trip-Time (RTT). Using ns-2 simulation, we show that the proposed scheme reduces the probability of packet contention and improves TCP performance.

• KIEAE Journal
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• v.13 no.4
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• pp.27-32
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• 2013

This study focus on shaft box facade, special form of box window construction. It consists of a system of box window with continuous vertical shafts that extend over a number of stories to create a stack effect. The subject building was decided by analyzing various types of exiting apartments. Shaft box type balcony was devised by setting up shaft space at a part of balcony. Air flow and indoor air temperature were simulated, performance of shaft box type balcony was compared with existing types using VE computer simulation program. Research consequence can be summarized as follow: 1) In the case of existing types, the change of window opening rate has only a little effect on the improvement of indoor temperature. But, air flow rate increased two times in the case that changed opening rate 20% to 40% 2) In the case of existing types, the growth of air flow rate has little effect on the improvement of indoor temperature. But, shaft box type represented the remarkable effect on the improvement of indoor temperature as well as the growth of air flow rate.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.525-530
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• 2013

With the increasing the importance of emotional quality of vehicle, the sound quality of systems with electric motor components has become increasingly important. Electric motors are used for windows, seats, sun roof, mirrors, steering columns, windshield wiper, climate control blowers, etc. In this paper, a study was conducted to identify sound quality factors that contribute to customer's satisfaction and preference of the window lift system. Jury test for subjective evaluation was carried out and sound quality index was developed. Averaged sound pressure level and sharpness were significant factors when glass moves down. Also, maximum loudness at stop section and averaged loudness were significant factor when glass moves up. Noise source identification was carried out for the reduced the loudness and sharpness during glass transferred section and impulsive noise at stop section, Using the source identification result, several improvement points were applied. And finally, the degree of sound quality improvement was judged using sound quality index.