• Journal of the Institute of Electronics Engineers of Korea TE
• /
• v.37 no.1
• /
• pp.35-41
• /
• 2000

This paper considers the consturction of 24/25 I-NRZI (Interleaved - Non Return to Zero Inverse) modulator designs for DVCR (Digital Video Cassette Recorder), and size of validity bit in order to store the amplitude value of square-wave and the standard data ( sine and cosine coefficients) at ROM Table that to acceptable the spectrum standard. The validity bit size of the standard data and the amplitude value of square-wave that to store at ROM Table are affected the size of pilot signal on the output spectrum, and the hardware size of modulator. At the designable 24/25 I-NRZI modulator, we simulated using random pattern (F0,F1,F2) that to verification the output data of the spectrum. Moreover, the resultant of the spectrum analysis, at the optimizing value, is 0.065 on the amplitude value of square-wave, and 3bit on the size of bit in order to store the standared data at ROM Table. In order to verify the hardware of designable 24/25 I-NRZI modulator, we perform to modeling of C-language firstly, and coding to Verilog HDL (Cadence Verilog XL) and synthesized using Synopsys (Library "Samsung KG75") tool as a base of spectrum results. In a foundation of this result, we are considered the size of hardware. In this paper, a considerable 24/25 I-NRZI modulator designable less than 10,000 gates as that is improved consturction as regards the path method of pre-coder etc, and able to application digital camcorders as now practical use.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.26 no.11A
• /
• pp.1827-1840
• /
• 2001

In digital data transmission/storage systems, the compensation for channel distortion is conducted normally using a training sequence that is known a priori to both the sender and receiver. The use of the training sequences results in inefficient utilization of channel bandwidth. Sometimes, it is also impossible to send training sequences such as in the burst-mode communication. As such, a great deal of attention has been given to the approach requiring no training sequences, which has been called the blind equalization technique. On the other hand, to utilize the limited bandwidth effectively, the concept of partial response (PR) signaling has widely been adopted in both the high-speed transmission and high-density recording/playback systems such as digital microwave, digital subscriber loops, hard disk drives, digital VCRs and digital versatile recordable disks and so on. This paper is concerned with blind adaptive equalization of partial response channels whose transfer function zeros are located on the unit circle, thereby causing some problems in performance. Specifically we study how the problems of blind channel equalization associated with the PR channels can be improved. In doing so, we first discuss the existing methods and then propose new structures for blind PR channel equalization. Our structures have been extensively tested by computer simulation and found out to be encouraging in performance. The results seem very promising as well in terms of the implementation complexity compared to the previous approach reported in literature.

• The Journal of Korean Academy of Prosthodontics
• /
• v.31 no.3
• /
• pp.394-410
• /
• 1993

This study was accomplished for appreciation of the mandibular moments according to antero- posterior movement of pivot placed on the lower natural dentition. For this study, 20 subjects(male, $21\sim30$ yrs., average age 24) in the category of normal occlusion were selected, and the intraoral Vitallium clutches were cast and fabricated for each subjects. A 2-dimension PSD(Position Sensitive Detector, Hamamatsu Photonics Co., Japan) was attached to maxillary clutch in a mode of three dimensional control and LED (Light Emit Diode, Hamamatsu Photonics Co., Japan) was set up on mandibular clutch. Both clutches were set into oral cavity of each subjects and adjusted. Then the subjects were allowed to intercuspated with maximal bite force while the pivoting ball in the mid-line moving from anterior toward posterior position. The displacement scales were recorded by CCD camera(Sony, CCD-TR-705) and VCR, The conclusions were as follows : 1. When the subject was allowed to bite the metal pivoting ball in the midline of lower dentition with maximal bite force voluntarily while moving from lower central incisor to canine, 1st premolar, End premolar, 1st molar and 2nd molar. The lever actions on the pivot were revealed in all subjects. The equilibrium of moment were revealed on the pivots of 1st premolar(14 subjects), End premolar(4 subjects), and canine(2 subjects) areas. 2. The changes of loading on the TMJ according to antero-posterior positional changes of metal pivoting ball were able to recognize as follow. Compression on the TMJ was increased when the pivot moves anteriorly from the equilibrium point, and tension on the TMJ was increased when posteriorly. 3. 13 subjects were recognized their habitual chewing sides(Rights, Left8), and 7 subjects were not. During maximal biting, mandible was displaced toward their habitual chewing sides on the metal pivoting ball in the frontal plane. 4. In cephalometric analysis, the average genial angle of 20 subjects was $116.75^{\circ}$ and the average mandibular body length was 79.77mm. The equilibrium points of mandibular moment were positioned more posteriorly in the subjects having larger Genial angle than in the smaller(p<0.05). Relationships among the angle between FH plane and occlusal plane, the angle between occlusal plane and mandibular plane , and mandibular body length were not significant(p>0.05).

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.8A
• /
• pp.739-752
• /
• 2002

Recently, to utilize the limited bandwidth effectively, the concept of partial response (PR) signaling has widely been adopted in both the high-speed data transmission and high-density digital recording/playback systems such as digital microwave, digital subscriber loops, hard disk drives, digital VCR's and digital versatile recordable disks and so on. This paper is concerned with adaptive equalization of partial response channels particularly for the magnetic recording channels. Specifically we study how the PR channel equalizers work for different choices of desired or reference signals used for adjusting the equalizer weights. In doing so, we consider three different configurations that are actually implemented in the commercial products mentioned above. First of all, we show how to compute the theoretical values of the optimum Wiener solutions derived by minimizing the mean-squared error (MSE) at the equalizer output. Noting that this equalizer MSE measure cannot be used to fairly compare the three configurations, we propose to use the data MSE that is computer just before the final detector for the underlying PR system. We also express the data MSE in terms of the channel impulse response values, source data power and additive noise power, thereby making it possible to compare the performance of the configurations under study. The results of extensive computer simulation indicate that our theoretical derivation is correct with high precision. Comparing the three configurations, it also turns out that one of the three configurations needs to be further improved in performance although it has an apparent advantage over the others in terms of memory size when implemented using RAM's for the decision feedback part.

• Korean Journal of Food Science and Technology
• /
• v.32 no.2
• /
• pp.312-316
• /
• 2000

Crude xylooligosaccharides(XO) were separated with a cellulose membrane (10,000 molecular weight cut-off). Flux variation was measured at transmembrane pressures of 5, 10, 20 and 30 psi, while flow rates were maintained at 100, 200, 300 and 400 ml/min and temperatures at 10, 20, 23-25 and $30^{\circ}C$. Optimal conditions were found at the transmembrane pressure of 20 psi, the flow rate of 300 ml/min and the temperature of $23-25^{\circ}C$, where the flux was decreasing with time by 62% after 200 min. Total sugar, total solid and ash contents were rather independent of ultrafiltration but protein was removed up to 55% from crude XO. Especially, the use of ultrafiltration was very effective for decolorization (84%) of crude XO. These results suggest that ultrafiltration is a useful method for the primary purification of XO.

• Journal of Animal Science and Technology
• /
• v.45 no.6
• /
• pp.1089-1096
• /
• 2003

We investigated postpartum behaviors of sows and their litters. The aim of this study was to determine the behavioral recovery of sows and the behavioral development of their piglets postpartum. Five multiparous sows(Landrace${\times}$Yorkshire) and their litters were studied over a period of 5 days postpartum. The litter size varied from 8 to 13 with a mean of 11.2 piglets. The behaviors of sows and their piglets were recorded using five CCD cameras, a multiplexer and a time lapsed VCR. The videotapes were scanned every 2 min to obtain an instantaneous behavioral sample. In the behaviors of sows, ‘Lying ventrally’ increased from 1 h postpartum to 26 h postpartum, then decreased gradually, and stabilized after 80 h postpartum. ‘Lying laterally’ decreased from 1 h postpartum to 26 h postpartum and stabilized after 80 h postpartum. ‘Standing, drinking and feeding’ increased from 1 h postpartum to 23 h postpartum, then decreased gradually, and increased again from 60 h postpartum. ‘Sitting’ increased from 1 h postpartum to 46 h postpartum and then decreased. In the behaviors of piglets, ‘Lying’ increased rapidly from 1h postpartum to 45h postpartum, and then was maintained at an almost constant level. ‘Massaging and Suckling’ decreased rapidly from 1 h postpartum to 36 h postpartum, and then was maintained at an almost constant level. ‘Walking’ increased from 1 h postpartum to 21 h postpartum, then decreased gradually. These results suggest that the behavioral recovery of the sow is almost completed at 80h postpartum and that the behavioral development of the piglet is almost completed at 45h postpartum.

• Journal of Embryo Transfer
• /
• v.14 no.1
• /
• pp.17-22
• /
• 1999

To investigate the maturational and development competece of porcine oocytes of different diameter groups, oocytes were obtained by aspiration from slaughterdhouse ovaries. After washing three times in NCSU23 medium, each cumulus-oocyte complex was transferred into a $8{mu}ell$ drop of the maturation medium (one oocyte per drop) under paraffin oil. The diameter without zona pellucida of oocytes was measured with micor-calibrator (Mikrometer, E. Leitz) on a screen connected to a VCR on an inverted microscope $(200\times)$. After being measured, the oocytes were divided into 6 groups according to their diameter size : <105, 105 to < 110, 110 to < 115, 115 to < 120, 120 to < 125 and > $125{\mu}{\textrm}{m}$, and in vitro maturation (IVM), fertillzation (IVF) and production (IVP) of oocytes / embryo was performed. The rates of in vitro maturation on oocytes in the greater 105 ${\mu}{\textrm}{m}$ size groups(91.8~100%) were significantly (P<0.05) higher than in the < 105 ${\mu}{\textrm}{m}$ group(66.7%). The rates of sperm penetration were significantly (P<0.05) low in < $105{\mu}{\textrm}{m}$ group (50.0%) than others groups (81.6~85.5%). But the plyspermic fertilization rate was significantly (P<0.05) higher in < $110{\mu}{\textrm}{m}$ oocytes groups than in the $110\leq{\mu}{\textrm}{m}$ size groups. The rates of cleavage and development to blastocysts rose as oocytes diameter increased, however, while oocytes over $120{\mu}{\textrm}{m}$ in diameter failed to develop to blastocysts. There results suggest that porcine oocytes have acquired full meiotic competece at a diameter of $105{\mu}{\textrm}{m}$ but not yet attended full development competence to blastocyst and that oocytes have acquired full development competence at a diameter of $110{\mu}{\textrm}{m}$.

• Korea journal of population studies
• /
• v.31 no.3
• /
• pp.57-84
• /
• 2008

This study investigates the patterns of leisure in Korea and the effects of social class on the objective and subjective dimension of leisure activities and life satisfaction. A data set of 1376 Korean men and women over 18 years old is analyzed to yield five main results. First, Korean prefers domestic entertainment to outdoor activities as is exemplified by domestic audio-visual entertainment(TV/DVD/VCR) which ranks the highest in the favored leisure activity. Leisure activities are divided into four types; "activity-based", "relationship-based", "alcohol-based", "relaxation". Second, the function of leisure activity is to strengthen relationships. The main purpose of leisure activity is to relax and revitalize, while creating prospective social network ranks next to relax. But the effect of leisure time is often compromised by recurring thoughts related to work. Third, respondents with high educational and economic backgrounds are more likely to engage in "relationship-based," "activity-based", "alcohol-based" leisure type. However, such factors do not influence on "relaxation" type of leisure. While students and housewives rank highest in number of respondents, respondents with managerial/professional or white-collar/semi-professional occupations enjoy more diverse activities. Fourth, the effort to discern the significance of social class with respect to the leisure-activity-index revealed followings; the index scores elevate with higher education, younger age and higher income. Fifth, leisure-activity-index is the most important variable predicting leisure satisfaction. Leisure satisfaction is influenced by gender, age, income and occupation. The younger the age and higher the income, the higher it is the leisure satisfaction. Men are more satisfied with leisure activities than women. Students experience the highest satisfaction with leisure activities while service/sales workers, industrial/technical/blue-collar workers shows the least satisfaction. Also, the number of family members decreases significantly the leisure satisfaction. While "activity-based" leisure induces the highest satisfaction, "alcohol-based" leisure produces the least satisfaction. The frequency and diversity of leisure activities, and "activity-based" leisure incur the most positive effects on the life satisfaction.