• Journal of The Korean Association of Information Education
• /
• v.15 no.4
• /
• pp.561-569
• /
• 2011

In order to solve the problems of the information society and the reverse function of chatting, there is a growing need of seeking out approachable educational methods. Therefore, we need to offer that addresses these issues ethical education from elementary school years where the creation of sound personality and its course may be hurt unless otherwise. Yet, there is no detailed curriculum for chatting education which is one of the detailed education areas. Also, how to offer and utilize the chatting education has never been mentioned. Moreover, only reverse function of information-driven changes have been emphasized whereas their desirable functions and information ethical principles have been simply neglected. The paper presents the effectiveness for improvement the school chatting education.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2000.05a
• /
• pp.386-391
• /
• 2000

Due to its characteristics of acoustic wave energy absorption, punched structures are generally applied on the wall of anechoic room. When the acoustic wave propagates through the punched plates, its energy dissipates into thermal energy by flow separation induced from the viscosity of acoustic media. The acoustic pressure difference between the for-side and the aft-side of punched plate ran be represented by the sum of drag term proportional to square of velocity and inertia term proportional to acceleration. The way to get the coefficients of the terms by an experiment or relatively simple calculation is introduced.

• ETRI Journal
• /
• v.31 no.4
• /
• pp.365-375
• /
• 2009

In this paper, a terrestrial digital multimedia broadcasting (T-DMB) multichannel audio broadcasting system based on spatial audio coding is presented. The proposed system provides realistic multichannel audio service via T-DMB with a small increase of data rate as well as backward compatibility with the conventional stereo-based T-DMB player. To reduce the data rate for additional multichannel audio signals, we compress the multichannel audio signals using the sound source location cue coding algorithm, which is an efficient parametric multichannel audio compression technique. For compatibility, we use the dependent property of an elementary stream descriptor, and this property should be ignored in a conventional T-DMB player. To verify the feasibility of the proposed system, we implement the T-DMB multichannel audio encoder and a prototype player. We perform a compatibility test using the T-DMB multichannel audio encoder and conventional T-DMB players. The test demonstrates that the proposed system is compatible with a conventional T-DMB player and that it can provide a promisingly rich audio service.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.7 no.1
• /
• pp.231-246
• /
• 1994

A major problem for information retrieval research in the past three decades has been methodology, even though some progress has been made in obtaining useful results from methodologically sound experiments. Within a methodology, potential problems include artificial data generated by the researcher, small sample size interpretation of findings. Critics have pointed out that some room exists for improving methodology of information retrieval research; using existing data, having big enough sample size, including large numbers of search queries, introducing more control in relation to variables, utilizing more appropriate performance measures, conducting rests carefully and evaluating findings properly. Relevance judgments depend entirely on the perception of the user and on the situation of the moment. In an experiment, the best judge of relevance is a user with a well defined information need. Normally more than two categories for relevance judgments are desirable becase there are degrees of relevance. In experimental design, careful control of variables is meeded for internal validity. When no single database exists for comparison, existing operational databases should be used cautiously, Careful control for the variations of search queries, inter-searcher sonsistency, intra-searcher consistency and search strategies is necessary. Parametric statistics requiring rigid assumptions are not appropriate in information retrieval research and non-parametric statistics requiring few assumptions are necessary. Particularly, the sign test and the Wilcoxon test are good alternatives.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2008.02a
• /
• pp.173-178
• /
• 2008

본 연구에서는 영상음향의 사운드디자인 구조의 차이가 수용자에게 어떠한 감응도 변화가 있는가를 알아 보았다. 실험은 60초의 TV광고음향을 음악으로만 디자인한 음향트랙과(A), 음향효과와 음악으로 디자인한 음향트랙(B)을 청취하게 하여, 어떠한 사운드 구조가 감응도(주의력, 활성도, 감성도)에 더 유의한 영향을 미치는가를 알아 보았다. 실험은5명씩의 남.여 대학생을 대상으로 이루어 졌고 안정상태와 Fp1, Fp2를 중심으로 한 전두엽측정방식으로 한 뉴로피드백(Neuro feedback)뇌파측정방법으로 측정하였다. 그 결과, 음악으로만 디자인한 A음향트랙에서의 감응도는 주의((ATQ)와 활성도(ACQ), 감성도(EQ)모두가 증가했으나 B트랙보다는 낮았다. 음악+효과음으로 디자인한 B트랙에서는 주의력(ATQ), 활성도(ACQ),는 A트랙보다 증가하였으나 EQ(감성도)는 반대로 A트랙보다 낮았다. 결과적으로 영상에서 음향은 주의력과 활성도 에는 기본적으로 뇌의 변화에 작용하나 정서적인 면은 역시 음악이 유효한 것으로 나타났다. 그러나 강한 효과음들은 음악보다 주의력과 집중도를 높이기는 하나 스트레스적(SQ)지수는 오히려 높은 것으로 나타났다. 본 연구를 통하여 방송과 영화 등의 사운드구조는 영상과의 호흡을 기본으로 하지만 실제로 시각정보와 청각정보가 동시에 합쳐져서, 심리적으로 어떠한 영향을 미치는가를 뇌신경측정으로 고찰한 것에 의의가 있다.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.25 no.11
• /
• pp.739-746
• /
• 2015

Several damage counting methods can be applied for the fatigue issues of a ground vehicle system using strain data and acceleration data is partially used for a high cyclic loading case. For a vibration test, acceleration data is, however, more useful than strain one owing to the good nature of signal-to-random ratio at acceleration response. The test severity can be judged by the fatigue damage and the pseudo-damage from the acceleration response stated in ISO-16750-3 is one of sound solutions for the vibration test. The comparison of fatigue damages, derived from both acceleration and strain, are analyzed in this study to determine the best choice of fatigue damage over multi-spectral input pattern. Uniaxial excitation test was conducted for a notched simple specimen and response data, both acceleration and strain, are used for the comparison of fatigue damages.

• Computers and Concrete
• /
• v.25 no.3
• /
• pp.245-253
• /
• 2020

Vibrational analysis in microtubules is examined based on the nonlocal theory of elasticity. The complete analytical formulas for wave velocity are obtained and the results reveal that the small scale effects can reduce the frequency, especially for large longitudinal wave-vector and large circumferential wave number. It is seen that the small scale effects are more significant for smaller wave length. The methods and results may also support the design and application of nano devices such as micro sound generator etc. The effects of small scale parameters can increase vibrational frequencies of the protein microtubules and cannot be overlooked in the analysis of vibrating phenomena. The results for different modes with nonlocal effect are checked.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 2005.03a
• /
• pp.68-73
• /
• 2005

In succession of the previous works, seismo-acoustic analysis was conducted to collect ground truth events and to discriminate surface explosions from natural earthquakes in the Korean Peninsula for 2004. In this period, total 510 seismo-acoustic events corresponding to 10.8 percent of total seismic events occurred in and near the Korean Peninsula were analyzed and discriminated as artificial surface explosions. Events distribution of the seismo-acoustic events in 2004 is similar to the previous results of 1999-2003. And newly determined seismo-acoustic events were added to the surface explosions database. To extend infrasound detection capability, Korea Institute of Geoscience and Mineral Resources (KIGAM) and Southern Methodist University (SMU) installed new seismo-acoustic array (BRDAR) in Baekryoung Island last November, 2004. The array configuration and design is nearly same to previous seismo-acoustic arrays CHNAR, KSGAR, a triangular 1 km aperture. BRDAR consists of 5 short period vertical seismometers (GS-13) in seismic vaults and 13 microbarometers (Chaparral Model 2). Preliminary analysis using data collected from BRDAR shows an extension of infrasound detection capability to western part of the Korean Peninsula. Also, multiple observations of infrasound at BRDAR and other arrays gave an opportunity to localize sound source regions.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1042-1049
• /
• 2007

Recently, a theoretically-sound design approach, using an elastic multilayer model, is attempted in trackbed designs for the construction of high speed railways and new lines of conventional railways. In the elastic multilayer model, the stress-dependent resilient modulus($E_R$) is an important input parameter, that is, reflects substructure performance under repeated traffic loading. However, the evaluation method for resilient modulus using repeated loading triaxial test is not fully developed for practical purpose, because of costly equipment and the significantly fluctuated values depending on the testing equipment and laboratory personnel. In this study, the paper will present an indirect method to estimate the resilient modulus using dynamic properties. The resilient modulus of crushed stone, which is the typical material of sub-ballast, was calculated with the measured dynamic properties and the range of stress level of the sub-ballast, and approximated with the power model combined with bulk and deviatoric stresses. The resilient modulus of coarse grained material decreases with increasing deviatoric stress at a confining pressure, and increases with increasing bulk stress. Sandy soil(SM classified from Unified Soil Classification System) of subgrade was also evaluated and best fitted with the power model of deviatoric stress only.

• Journal of the Korean Geophysical Society
• /
• v.5 no.3
• /
• pp.219-231
• /
• 2002

Single beam echo sounding was used to delineate bathymetry sea bottom in the area of hydrography and marine navigation. This research was aimed at measuring the thickness of floating silty clay sediment with dual frequencies echo sounding system. There occur discrepancies in penetrating depth through sea beds between high frequency(200 KHz) and low(33 KHz) frequency. RI density logging was employed to characterize the floating silty clay sediment of Guangyang bay, which was chosen to investigate the proposed site for reclamation field. The volume of floating silty clay sediment was used to design by estimating size of reclamation site. The estimation strategies developed in this study will be readily applicable to measure the Pattern of sedimentation via regular hydrographic survey in the future.