• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11a
• /
• pp.316.2-316
• /
• 2002

There are a lot of roots of errors in the motion of the optical pickup actuator being one of the most significant components in the CD-ROM drive. Most of the studies recently performed have a tendency to seek fur the causes from an actuator itself. We found the fact that the range of the natural frequencies of a feeding deck and an actuator is close each other through an experiment. This paper present the dynamic characteristics of an actuator affected by the motion of a feeding deck. (omitted)

• Asian-Australasian Journal of Animal Sciences
• /
• v.8 no.4
• /
• pp.365-368
• /
• 1995

Lactation curves of dairy cows were generated using three models, namely; incomplete gamma function (model 1), polynomial inverse function (model 2) and non-linear regression (model 3). Secondary milk yield data of 27 cows which had completed 6 lactations were used in this study. Milk yield records (once a week) throughout the lactation and from the first three months of lactation were fitted to the models. Estimation of total milk yield by model 3 using the data once a week throughout the lactation resulted in smaller % bias and standard error than those generated from model 1 and 2. But, model 2 was more accurate in predicting the 305-day milk yield equivalent closer to actual yields with smaller bias % and error using partial records up to 3 months. Also, model 2 was able to estimate the time to reach peak yield close to the actual data using partial records and model 2 could be used as a tool to advise farmers on appropriate feeding and management practices to be adopted.

• The Journal of the Acoustical Society of Korea
• /
• v.18 no.8
• /
• pp.68-74
• /
• 1999

To investigate the relationship between voice and the image created by the voice, a perception experiment was undertaken in which voices of 8 males and 8 females reading a fairy tale were recorded and presented to 100 subjects along with the speakers' pictures. Two kinds of pictures were taken: one, a whole-body picture, and the other, a face-only close-up picture. Subjects were asked to match each voice with its owner. The results showed that out of 8, more than 4 were matched correctly. And the correct rate was higher when the voices were matched against the whole-body pictures than against the face-only pictures. In addition, it was noted that far more people picked a single voice as the most 'favorite' one than they picked one picture as the most 'favorite' image.

• Proceedings of the KSR Conference
• /
• 2001.10a
• /
• pp.514-519
• /
• 2001

There are a close relationship between natural disasters and train safety. So it is very important to guaranty train safety using reasonable rail-transport operation control against disasters. Therefore, based on the past record of rainfall at failure, rail-transport operation control for railway embankment under rainfall was set up. After slope check list at home and abroad had been analyzed, new slope check list was suggested and site investigations were carried out using this check list. In order to evaluate the stability of railway slopes under rainfall, explanatory variables and subordinate variables were selected for multi-variate analysis and critical rainfall was defined by statistical process. Rail-transport operation control including regional and geological properties was suggested by analyzing the critical rainfall and rail-transport operation control in other country, and this will be a good tool to control train speed under rainfall and to secure train safety.

• International Journal of Railway
• /
• v.4 no.3
• /
• pp.74-79
• /
• 2011

Recent years have witnessed speed up of moving vehicles such as high-speed of trains. Increase in speed entails concomitant increase in turbulent air flow which contributes toward increased aerodynamic noise. The proposed method for aerodynamic noise reduction is based on a biomimetic design of owl feather. The five morphological parameters of the owl feather are extracted from close observation, and simulation cases are constructed by applying design of experiments methodology. Swirling strength for each case is obtained through steady-state CFD analysis, and key morphological parameters that affect the turbulence are identified. Large eddy simulations (LES) are then performed on selected cases to predict the air turbulence. Different cases show varying vortex distributions which are expected to lead to varying aerodynamic noise levels.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.33 no.3
• /
• pp.71-78
• /
• 2010

The end shape of tube for automobile power steering system has influence on the ability of performance. In this case study, we attempted to optimize the forming process of a small tube using Taguchi experimental design methodology. A preliminary experiment was conducted and four main control factors were selected. The experiment was set up as an $L_9(3^4)$ orthogonal array, and determined the optimal levels of the four factors through the analysis of the experimental results. As a result, the performance characteristic(close adhesion power) of the product was improved about 36%. In addition, the process capability index $C_{pk}$ is enhanced from 0.94 to 6.85.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.5 no.1
• /
• pp.13-20
• /
• 1999

Not only is it important that the physical properties of the paperboards be appropriate for the intended end use, but the proper arrangement of the component in the built-up board is essential for attaining the optimum moment of inertia and the maximum load-carrying ability in a box. It is known to be impossible to estimate the stress distribution and deflection pattern by experiments or theoretical analysis when the corrugated fiberboard get the bending force. This study was tried theoretical and finite element analysis to analyze structural strength characteristics of corrugated fiberboards. If the linerboard and corrugating medium of every corrugated fiberboards is made from the same material, the location of neutral axis comes close to inside liner in order of DMA, DM, DMB, SW and DW, and moment of inertia of area decreases in order of DMA, DMB, DW, DM and SW. With the finite element analysis, deflection of applied loads represented SW, DM, DMA, and TW in the order of their value.

• Journal of KSNVE
• /
• v.22 no.4
• /
• pp.28-32
• /
• 2012

Condition-based maintenance on wind turbines not only involves maintenance, but also encompasses servicing, inspection, measurement and evaluation of the condition of the unit. The current condition can be evaluated on the basis of machine-specific overall vibration values. Until now, overall vibration values had not been defined for wind turbines. In fact, ISO 10816-3 explicitly excludes wind power plants. The new VDI 3834 closes this gap shown in Sheet 1: Vibration values for wind turbines up to 3 MW. In addition to the new VDI 3834 is the ISO 10816-21 in preparation. The author of the article Dr. Edwin Becker is the nominated expert for Germany.

• Biomolecules & Therapeutics
• /
• v.2 no.1
• /
• pp.28-33
• /
• 1994

In order to obtain insight into the repair mechanism of DNA containing thymine photo-dimer, the conformation of the duplex d(GCGGTTGGCG).d(CGCCAACCGC) with a thymine dimer incorporated has been studied by proton NMR. NOE data show that, although the local environment around the thymine dimer is altered, the gross structural changes are relatively small. T$_4$endonuclease V exhibited a conformational change on complex formation with DNA. This conformational change occurred around histidine 16 which was close to tyrosine 129 located in the aromatic segment (WYKYY) near the C-terminus. It is likely that the interaction between T$_4$endonuclease V and DNA is strong since the complex was not dissociated up to 1.6 M NaCl.

• Journal of the Korean Society of Costume
• /
• v.62 no.8
• /
• pp.19-27
• /
• 2012

Shinyeojuryeom is a set of bamboo blinds[Juryeom] enclosing the Korean litter for transporting a mortuary tablet of royal family[Shinyeo] in Joseon dynasty. The blinds were made up of twigs laid horizontally which were joined together by vertical threading, then they were lined and backed with silk fabric. A number of historical documents such as Gukjosangryebopyeon(1758), JeongjoGukjangdogameuigwe(1800) and Gukjangdogam- myeongseseo(1905) provide information on material and structure of the litter and blinds. How- ever, detailed dimensions or specific ingredients of some of the materials were not clearly explained. In order to complement these missing or unclear parts, a close examination and scientific analysis of the litter's material was undertaken. The result newly identified materials of the gold tip tassels and pigments used on twigs as well as partly confirmed information on historical records. This new information will help further understanding and future production of a replica.