• International journal of advanced smart convergence
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• v.11 no.4
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• pp.240-246
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• 2022

In order to measure the respiratory rate, one of the major vital signs, many devices have been developed and related studies have been conducted. In particular, as the number of wearers of respirators increases in the COVID-19 pandemic situation, studies have been conducted to measure the respiratory rate of the wearer by attaching an electronic sensor to the respirator, but most of them are cases in which an air flow sensor or a microphone sensor is used. In this study, we design and develop a system that measures the respiratory rate of the wearer using an air pressure sensor in a respirator. Air pressure sensors are inexpensive and consume less power than the other sensors. In addition, since the amount of data required for calculation is small and the algorithm is simple, it is suitable for small-scale and low-power processing devices such as Arduino. We developed an algorithm to measure the respiratory rate of a respirator wearer by analysing air pressure change patterns. In addition, variables that can affect air pressure changes were selected, and experimental scenarios were designed according to the variables. According to the designed scenario, we collected air pressure data while the respirator wearer was breathing. The performance of the developed system was evaluated using the collected data.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.75-83
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• 2015

The applicability of oil palm biomass, EFB(Empty Fruit Bunch) as raw materials for environmental friendly packaging material, pulp mold, was evaluated in this study. The changes in the water absorption properties of pulp mold by the addition of EFB and the surface treatments with PVA and AKD were analyzed by measuring the changes in the water absorption rate and the water contact angle. The each pulp mold sample was prepared by using laboratory wet pulp molder. And the water absorption rate of each samples were evaluated by measuring times for the absorption of a 0.1 ml water drop on the pulp mold sample surface. The addition of EFB to the pulp mold made of OCC resulted in the decrease of water absorption rate and the increase in the water contact angle. The surface treatments with PVA and AKD on the OCC pulp mold showed the significant reduction in the water absorption rate. However, in case of ONP pulp mold, the addition of EFB and the surface treatments with PVA and AKD showed no big changes in water absorption times. Those might be come from the finer surface structure of ONP pulp mold which were made of more finer and flexible fibers and more hydrophilic fibers. The results of this study showed the functional properties such as water absorption rate, could be controlled by the application of EFB and the treatments with AKD or PVA, especially in case of the OCC pulp mold.

• Food Science of Animal Resources
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• v.40 no.2
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• pp.231-241
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• 2020

The current study investigated the effects of timing of NaCl (2%) and sodium tripolyphosphate (STPP, 0.5%) addition and cooking rates on color and pigment properties of ground chicken breasts. Four treatments were tested as follows: treatment 1, no NaCl and STPP added and stored for 7 d; treatment 2, NaCl+STPP added on 0 d and stored for 7 d; treatment 3, NaCl added on 0 d and STPP added on 7 d; and treatment 4, stored for 7 d and NaCl+STPP added. All samples were cooked at a fast (5.67℃/min) or slow cooking rate (2.16℃/min). Regardless of the timing of NaCl and STPP addition, reflectance ratios of nitrosyl hemochrome, cooking yield, pH values, oxidation-reduction potential, and percent myoglobin denaturation were similar (p>0.05) across treatments 2, 3, and 4. The highest CIE a^⁎ values were observed in treatment 4 (p<0.05), while treatment 2 was effective in reducing the redness in cooked chicken products. The fast cooking rate resulted in lower CIE a^⁎ values and higher CIE L^⁎ values and cooking yield in cooked chicken breasts compared to the slow cooking rate. Our results indicate that adding NaCl and STPP to meat, followed by storing and cooking at a fast rate, may result in inhibiting the pink color defect sporadically occurred in cooked ground chicken breasts.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.323-327
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• 1999

It was shown that brain-derived neurotrophic factors (BDNFs) secreted from human neuroblastoma cells can significantly improve the growth of the neurites of PC12 nerve cells. The addition of purified BDNFs elongated the neurites of PC 12 nerve cells two to three times more than the case where the addition was not made. The perfusion rate strongly affected the change of the size of human neuroblastoma cells because the cell size decreased as the perfusion rate increased. This could also influence the productivity of BDNF from the cells. It is also important to note that the BDNF production was decreased when the cell size was reduced. BDNF production rate also decreased at a fast perfusion rate in a smaller cell size. At the relatively fast perfusion rate of 18 ml/h, the ratio of apoptotic to necrotic cells dramatically decreased, which possibly caused the decrease of BDNF production. It has been proven that the secretion of BDNF from human neuroblastoma cells was a partially growth-related process by yielding 6.2$\times l0^{-8}/g$ of BDNF/cell/h of growth related parameter and $0.48{\times}l0^{-9}/g$ of BDNF/cell/h of nongrowth-related parameter in a growth kinetic model. In addition, it was also found that the perfusion rate played a very important role in controlling the cell death mechanism.

• The Research Journal of the Costume Culture
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• v.17 no.4
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• pp.535-547
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• 2009

This study presented a making method of jeans pattern with high fitness after deriving the appropriate shrinkage rate by material and washing process. For this purpose of this study, 6 jeans have been tested after washing finishing and we turned out appropriate shrinkage rate by evaluating the exterior of jeans and usage satisfaction. Then, a making method of jeans pattern was presented after applying the optimized shrinkage rate. According to the result of the exterior evaluation of test jeans, all 6 jeans were rated high with scores close to 3.5. Following the evaluation of satisfaction of usage by physical movement, the highest ranking was in the order of walking with normal steps, back bending $90^{\circ}$, chair sitting, climbing stairs, and squatting. The shrinkage rate by physical area showed the highest score in the order of pants length, waist circumference, thigh circumference, knee circumference, hem circumference, hips circumference. In addition, the shrinkage rate was higher in warp direction than weft direction after washing finishing. As for the result of addition and reduction of pattern measurements by parts of jeans, waist circumference was 2.6${\sim}$5.2cm, hips circumference was 1.3${\sim}$4.2cm, thigh circumference was 0.8${\sim}$3.1cm and knee circumference was 0.7${\sim}$2.5cm. Also, hem circumference was 0.5${\sim}$1.8cm and pants length was 4.0${\sim}$6.2cm. That is, this results showed a wide range of addition and reduction according to material and washing finishing.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.157-163
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• 2010

A new etchant formulation was developed in this study to increase the shadow mask production rate, utilizing the $Fe(ClO_4)_3$ as an additive in the aqueous $FeCl_3$ solution. The shadow mask etch rate increased substantially with the increase of $Fe(ClO_4)_3$ concentration in the etchant. The etch rate difference between Ni and Invar steel was also reduced with the addition of $Fe{(ClO_4)_3}$ for most of the operating conditions, which was caused by the enhanced etch rate of both Ni and Fe by the new etchant. The increase in etch rate with the addition of $Fe(ClO_4)_3$ to aqueous ferric chloride solution was attributed to the superior electron transfer capability of $ClO^{4-}$ ion to that of $Cl^-$ ion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.71-72
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• 2022

In this paper, the performance evaluation of the vibration damping ratio according to the polymer mixing ratio of the polymer modified mortar used as the floor finishing material of the apartment building structure was evaluated. To compare the vibration damping rate, ordinary potland cement (OPC) mortar and polymer modified mortar (PMM) were prepared. In addition, the mixed polymer was mixed with Styrene Butadiene Rubber (SBR) liquid polymer with a solid content of about 49%. Accordingly, the W/C of the test specimen was adjusted and compounded, and the experiment was conducted by mixing 5 types of the test specimen: OPC-60, PMM-5%, PMM-10%, PMM-15%, and PMM-20%. In addition, in order to adjust the W/C of the specimen, the fluidity of each specimen was set as 210 (±5) mm. The specimens measured density and flow in fresh mortar and after curing for 28 days, flexural strength, compressive strength and ultrasonic pulse were measured. The attenuation rate was shown. The experimental results showed that the density increased according to the mixing of the polymer, the flexural strength increased as the mixing rate of the polymer increased, and the compressive strength was decreased. In addition, it was shown that the vibration damping rate increases with the increase in the amount of polymer incorporated.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.755-759
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• 2013

The etch rate and etch profile of Si was investigated when Ar was added to an $SF_6$ plasma in the etch step of the Bosch process. A Si substrate was etched with the Bosch process using $SF_6$ and $SF_6$/Ar plasmas, respectively, in the etch step to analyze the effects of Ar addition on the etch characteristics of Si. When the Ar flow rate in the $SF_6$ plasma was increased, the etch rate of the Si substrate increased, had a maximum at 20% of the Ar flow rate, and then decreased. This was because the addition of Ar to the $SF_6$ plasma in the etch step of the Bosch process resulted in the bombardment of Ar ions on the Si substrate. This enhanced the chemical reactions (thus etch rates) between F radicals and Si as well as led to sputtering of Si particles. Consequently, the etch rate was higher more than 10% and the etch profile was more anisotropic when the Si substrate was etched with the Bosch process using a $SF_6$/Ar (20% of Ar flow rate) plasma during the etch step. This work revealed a feasibility to improve the etch rate and anisotropic etch profile of Si performed with the Bosch process.

• Korean Journal of Animal Reproduction
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• v.11 no.1
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• pp.73-84
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• 1987

This experiment was carried out to investigate the effects of hormone addition(FSH, HCG, estrogen and progesterone) and composition (BSA and FCS) of mKRB on the in vitro maturation and fertilizability of follicular oocytes of the Korean native cattle. The ovaries were removed at a slaughterhouse, returned to laboratory in a thermostat (30-35$^{\circ}C$) within 4 hr, and collected by aspirating normal follicles which had diameters of 1 to 6 mm. The oocytes with cumulus cells were cultured for 8, 16, 24 and 30 hr in a modified KRB solution containing BSA or FCS and hormones. The in vitro matured oocytes in mKRB containing FCS, FSH and steroids were transferred in the rabbit uterus for examination of their in vivo fertilizability with bovine sperm preincubated 4 to 6 hr in the rabbit uterus. 1. The mean number of oocytes collected per cattle was 6.5 from 1-3mm follicles, 1.3 from 4-6mm follicles, and total was 7.7. 2. The meiotic division at 16hr-cuture in the oocytes from 1-3mm follicles was slightly stimulated by the addition of FSH in mKRB + BSA solution compared with the control. At 30hr-culture, their maturation rates(%Met II) were also increased by FSH of 1 $\mu\textrm{g}$/ml(38.4%) and 5$\mu\textrm{g}$/ml(35.7%) as compared with the control (21.4%). The maturation rate at 30hr-culture in the oocytes from 4-6mm follicles was 53.8% and 57.1% by the FSH addition of 1$\mu\textrm{g}$/ml and 5$\mu\textrm{g}$/ml, respectively. These rates were similar with the control(57.1%), but higher than those of oocytes from 1-3mm follicles. 3. The meiotic division at 16hr-culture in the oocytes from 1-3mm follicles was stimulated by the HCG addition of 1IU/ml and 5IU/ml. However, the maturation rate at 30hr-culture was greatly decreased by the HCG addtion (26.6% and 13.3%) compared with the control(53.3%) and these rates (30.8%) in the oocytes from 4-6mm follicles were also lower than that fo the control(58.3%). 4. Low maturation rate (37.5%) of the oocytes cultured in mKRB containing BSA and 5IU/ml HCG was increased (55.0%) when 15% FCS with HCG was added to mKRB instead of BSA. 5. When 16hr-cultured oocytes in mKRB containing BSA and gonadotropins (5$\mu\textrm{g}$/ml FSH and 5IU/ml HCG) were transferred in the medium without gonadotropins and recultured for 16hr, the maturation rate of HCG-treated oocytes was greatly improved. 6. The maturation rates of oocytes were greatly affected by steroids. The combined addition of FCS+FSH+estrogen or +progesterone to mKRB increased the maturation rate compared with the combination of BSA+FSH or FCS+FSH in mKRB. 7. The fertilization rate, presence of pronuclei, was increased by the combination of FCS+FSH+p in mKRB as compared with that (5.6%) of BSA+FSH and the rates of FCS+FSH+steroids ranged from 12.5 to 17.6%.

• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1898-1903
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• 2007

We attempted to modulate the overall protein expression rate through the addition of a repressor against the araBAD promoter system of Escherichia coli, in which glucose was used as a repressor. Therefore, 0.5% L-arabinose was initially contained as an inducer in culture medium, and either 2% glucose or 2% glycerol was used as a carbon source, and it was found that the expression of recombinant interferon-${\alpha}$ could be observed at the beginning of the batch culture when glycerol was used as a carbon source. However, when glucose was used, the initiation of recombinant interferon-${\alpha}$ expression was delayed compared with that when glycerol was used. Furthermore, when the addition of 0.5% glucose was carried out once or twice after 0.5% L-arabinose induction during DO-stat fed-batch culture, the distributions of soluble and insoluble recombinant interferon-${\alpha}$ were modulated. When glucose was not added after the induction of L-arabinose, all of the expressed recombinant interferon-${\alpha}$ formed an inclusion body during the later half of culturing. However, when glucose was added after induction, the expressed recombinant interferon-${\alpha}$ did not all form an inclusion body, and about half of the total recombinant interferon-${\alpha}$ was expressed in a soluble form. It was deduced that the addition of glucose after the induction of L-arabinose might lower the cAMP level, and thus, CAP (catabolite activator protein) might not be activated. The transcription rate of recombinant interferon-${\alpha}$ in the araBAD promoter system might be delayed by the partial repression. This inhibition of the transcription rate probably resulted in more soluble interferon-${\alpha}$ expression caused by the reduction of the protein synthesis rate.