• ETRI Journal
• /
• v.30 no.2
• /
• pp.261-267
• /
• 2008

In this paper, we propose and demonstrate a cost-effective technique to upgrade the capacity of dense wavelength division multiplexing (DWDM) networks to a 40 Gb/s line rate using the existing 10 Gb/s-based infrastructure. To accommodate 40 Gb/s over the link optimized for 10 Gb/s, we propose applying a combination of super-FEC, carrier-suppressed return-to-zero, and pre-emphasis to the 40 Gb/s transponder. The transmission of 40 Gb/s DWDM channels over existing 10 Gb/s line-rate long-haul DWDM links, including $40{\times}40$ Gb/s transmission over KT's standard single-mode fiber optimized for 10 Gb/s achieves successful results. The proposed upgrading technique allows the Q-value margin for a 40 Gb/s line rate to be compatible with that of 10 Gb/s.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.15 no.2
• /
• pp.134-139
• /
• 2004

A clock recovery circuit for a 40 Gb/s optical receiver has been designed and implemented. The clock recovery circuit consists of pre-amplifiers, a nonlinear circuit with diodes, a bandpass filter and a clock amplifier. Before implementing the 40 Gb/s clock recovery circuit, a 10 Gb/s clock recovery circuit has been successfully implemented and tested. With the 40 Gb/s clock recovery circuit, when a 40 Gb/s signal of -10 dBm was applied to the input of the circuit, the 40 GHz clock was recovered with the -20 dBm output power after passing through the nonlinear circuit. The output signal from the nonlinear circuit passes through a narrow-band filter, and then amplified. The implemented clock recovery circuit is planned to be used for the input of a phase locked loop to further stabilize the recovered clock signal and to reduce the clock jitter.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.20 no.3
• /
• pp.240-244
• /
• 2007

We investigated the diffraction grating efficiency by the Diode Pumped Solid State(DPSS 532 nm) laser beam wavelength to improve the diffraction efficiency on $As_{40}Ge_{10}Se_{15}S_{35},\;Ag/As_{40}Ge_{10}Se_{15}S_{35}$ and $As_{40}Ge_{10}Se_{15}S_{35}/Ag/As_{40}Ge_{10}Se_{15}S_{35}$ thin film. Diffraction efficiency was obtained from DPSS laser, used (P:P)polarized laser beam on each thin films. As a result, for the laser beam intensity in $0.24mW/cm^2$, single $As_{40}Ge_{10}Se_{15}S_{35}$ thin film shows the highest value of 0.161% diffraction efficiency at 300 s and for laser beam intensity in $2.4mW/cm^2$, it was recorded with the fastest speed of 50 s(0.013%), which the diffraction grating forming speed is faster than that of $0.24mW/cm^2$ beam. $Ag/As_{40}Ge_{10}Se_{15}S_{35}$ double layer and $As_{40}Ge_{10}Se_{15}S_{35}/Ag/As_{40}Ge_{10}Se_{15}S_{35}$ multi-layered thin film also show the faster grating forming speed at $2.4mW/cm^2$ and higher value of diffraction efficiency at $0.24mW/cm^2$.

• Fashion & Textile Research Journal
• /
• v.20 no.6
• /
• pp.733-743
• /
• 2018

This study aimed to investigate whether women's wear brands' sizing systems for pants item are reflecting body size and shape of their target age customers. This study classified 17 women's wear brands into three target age groups (20-30s, 30-40s, and 40-50s) and surveyed their body sizing systems of pants item. Distribution of waist circumference and hip circumference of brands' sizing systems were compared with size distribution of women in the 7th Size Korea data. The sizing systems of brands targeting 20-30s covered 28.3% and those of brands targeting 40-50s covered 27.3%, while those of brands targeting 30-40s covers 46.6%. Regarding the body types, 80% of 20-30s target brands reflected normal type which is the average body type. However, all 40-50s target brands reflected normal type while 57.8% of women aged 40-50s had large waist shape. The 30-40s target brands reflected body types the best among target age groups since the body shape distribution of the brands was similar to that of 30-40 year old woman in Size Korea. For each age group, 6 sizes with 25.2~27.8% coverage rates were proposed. The 70-91, 73-91, 73-94 sizes were overlapped between the 20-30s and the 30-40s groups. The 76-91, 76-94, 79-94 sizes were overlapped between the 30-40s and 40-50s groups. Pants size has been found to increase in waist circumference compared to hip circumference as age increased.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.4B
• /
• pp.637-646
• /
• 2010

For 40 Gb/s data transmission through electrical backplane trace up to 40 inch length on four layer fire-resistant (FR-4), we have designed the 40 Gb/s backplane channel model consisting of four channel 10 Gb/s. Simulation results show an enhancement of backplane channel characteristics excellent more than requirements specified in IEEE P802.3ba at 10 Gb/s. This paper provides a review of the structures and algorithms used in receive and adaptive equalization for 40 Gb/s backplane Ethernet. The use of this backplane channel model could achieves better receive equalizer at great data rate than 10 Gb/s.

• Journal of the Korean Home Economics Association
• /
• v.34 no.2
• /
• pp.85-97
• /
• 1996

The purpose of this study was to analyze the differences of breast shapes by age, to classify breast types, and to investigate the characteristics of breast shapes by type and the distributions of types by age group, using comparative analysis for women in 20's and 40's. The subjects of anthropometry were 323 women in 20's and 40's. The anthropometric measurements were analyzed by mean, standard deviation, frequency, T-test, F-test, Duncan test, factor and cluster analysis. The results are as follws : 1) According to the increase of age, the items of height were decreased and the items of width, depth, circumference and length were increased, being obeser and breast points were dropped. So the volume and bottom area of 40's women's breast were larger than 20's women's and the breast point to breast point width of 40's women was being wider by the increase of the intereior of breast. 2) 6 factor were extracted from factor analysis by age group. There was no significant difference in consist of factor between age group. There was no significant difference in consist of facotr between age group, but were differences in the connection of factor extracted items and factor loading. Through factor analysis of all age froup, 5 factors were extracted as important factor of breast shapes (obesity of breast and location of breast point ; breast height and volume ; upper dimensions of breast/lower dimensions of breast ; interior dimensions of breast/exterior dimensions of breast ; volume of the lower part and drop of breast). 3) The breast shapes were classified into 4 types by cluster analysis. The frequency of 20's women's breast types appeared in order of type1(53.0%), type3(32.0%), type2(11.0%), type4(4.0%), but that of breast types of 40's women appeared in order of type2(37.9%), type3(31.1%), type4(26.5%), type1(4.5%). Namely, there was few type4 in 20's women and few type1 in 40's women. 20's women's breast types were characterized as type1·3 and type2·3·4 in 40's women. So 40's women had more various breast types than 20's women's.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.24 no.4
• /
• pp.41-56
• /
• 2022

This study aims to investigate the actual condition of wearing leggings and the preferred design of down-aging women in their 30s and 40s who have young sensibility, but are starting to enter a middle-aged body type. By analyzing the problems experienced when wearing leggings in this age group, this study intends to provide basic data for the development of a middle-aged female leggings pattern with an improved fit. Therefore, a survey was conducted on 214 women in their 30s and 40s. The results of the survey are as follows. Among down-aging women who want to look younger, leggings are becoming an essential item, but most leggings brands are producing leggings with patterns suitable for women in their 20s. The results of this study also showed that down-aging women in their 30s and 40s mainly purchase and prefer body-fitting leggings. However, they are experiencing discomfort due to 'Y-zone accentuate', 'undergarment accentuate', 'cloth stucking', and 'waist band curling and tightening'. The results indicate that women in their 30s and 40s, who are starting to change to a middle-aged body type, have fit problems. Women in their 20s generally prefer functions that improve the body line, while those in their 30s and 40s prefer functions that improve movement and cover problems caused by the abdomen and the Y-zone area. Therefore, when designing leggings for down-aging women in their 30s and 40s, based on body-fitting leggings, a material with excellent elasticity must be selected. Also develop patterns that solves 'Y-zone accentuate', 'undergarment accentuate', 'cloth stucking', and 'waist band curling and tightening' problems.

• Journal of the Korean Society of Costume
• /
• v.55 no.4 s.94
• /
• pp.16-28
• /
• 2005

The purposes of this study were to understand the buying patterns of adult women according to impulse shopping, benefits sought, and selecting information sources. This subjects of this study were 509 adult women from the age 20's to the age of 40's. This data were analyzed by using factor analysis multi regression analysis, analysis of variance, Scheffe' test. The results of this study were outlined as follow: 1. Differences among ages (the 20's, the 30's, and the 40's) in impulse shopping were as follow: The 30's bought more cosmetics to change their mood compared to the 20's or the 40's, and the 20's and the 30's bought more cosmetics matching to their images compared to the 40's. 2. From the aspects of benefits sought, the 20's and the 30's were more seriously consider the fame of brands compared to the 40's, showing they were different from the 40's. 3. From the aspects of selecting information sources about cosmetics, the 20's were more actively utilizing both human information sources and non-human information sources compared to the 30's and the 40's.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.16 no.3
• /
• pp.201-217
• /
• 2014

There is likely to be a fit problem when women aged in their 30s-40s purchase down-age clothing from brands that target women in their 20s. To identify the part of the lower body that causes the fit problem, the sizes and types of lower body of women in their 30s-40s were compared with those of women in their 20s. The data for this study was from the 2010 Size Korea survey of body measurements of 1675 female adults in their 20s-40s. To examine differences in the average sizes of the lower body between women in their 20s and 30s-40s, descriptive statistics and t-tests were conducted. Factor and cluster analysis were used to classify body types by age groups. On the whole, compared to women in their 30s-40s, women in their 20s were found to be higher for all height items and smaller for size, thickness and width items. The result of the Glycemic index analysis showed that the body type of women in their 20s was generally larger than that of women in their 30s-40s. In addition, women in their 20s had a large drop value compared to those in their 30s-40s, whereas flatness of body cross section was bigger in the group of women in their 30s-40s. Four factors related to the lower body type of female adults in their 20s-40s were identified in the factor analysis, and three categories of body type were identified by cluster analysis. A Type 1 individual had abdominal obesity and chubby lower limbs, Type 2 had short legs and slightly chubby lower limbs, and Type 3 had long legs and a skinny lower body. A significant number of women in their 30s-40s were included in the Type 1 group, which was the least common category for women in their 20s.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.2B
• /
• pp.197-209
• /
• 2010

In this paper, We have designed and analyzed a characteristics of backplane channel having 40 inch strip line length of four lanes and Flame Retardant four (PR-4) material, and have designed 40 Gb/s Receive and adaptive equalizer and its high-speed equalization algorithm using the backplane channel characteristics. For 40 Gb/s high-speed data communications pass through the backplane, a 10Gb/s 4 channel receive & equalizer with DFE except for FFE was proposed. This receive and equalizer meets the requirements of the IEEE Std P802.3ba standard-based receive equalizer to implement equalizers on the receive end of a 46 inch length's backplane channel.