• Journal of Institute of Control, Robotics and Systems
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• v.12 no.12
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• pp.1197-1201
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• 2006

In order to improve the operability in a fully thermally coupled distillation column the main column is separated into an upper and a lower column, and its design method is explained. With a distillation experiment using a two-inch column the operability of the proposed column is examined. Readily available methanol, ethanol and propanol are used as the feed, and the experimental result is compared with that of the HYSYS simulation. It is found from the experiment that the recovery ranges between 58.8% and 68% and the distillation efficiency is lower than that of the simulation. consumes less energy than an original column, it is not widely implemented in practice due to its operational difficulty. However, it is proved that the proposed distillation column can be operated without compressors and it can be practically utilized.

• Journal of Korean Society of Steel Construction
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• v.10 no.2 s.35
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• pp.161-175
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• 1998

The objective of this study is to investigate the structural behavior of Concrete-Filled Steel Tubular Column-H Beam connections with plate stiffeners. The first, we made experiment on the Column to H-beam flange connections stiffened with simple tensile loading. The paramaters of tensile experiment are the area of each plates. The simple tensile experiment is conducted to 5 kinds of specimens. Eestimating the load, displacement, and strain from each kind, we compared them with results of second experiment. The second, we made experiment on the Column to H-beam connections stiffened with the sames under monotonic and cyclic load. we made specimens of 5 for the second experiment. In analysis, comparing each strengthes and stiffnesses we estimated deformation capacity. Comparing and estimating each yielding strength ratios and maxium-strength ratios on the basis of Yield line theory, we suggested new Strength Formula of Beam-to-Column Connections.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.52-59
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• 2008

Adsorption is a major process causing the accumulation of arsenic onto soil. Therefore, further understanding of the adsorption/desorption characteristics of arsenic species on soil is essential for predicting their fate and preparing appropriate remediation strategy to remove arsenic from soil. In this study, the column adsorption/desorption experiment has been performed with As(III) and As(V) on soil. Experiment with As(III) was conducted under reducing condition, whereas that with As(V) was under oxidizing condition. Most of As(III) was remained on the oxidation state during the experiment. The results showed that the adsorption/desorption rate of As(III) was higher than that of As(V). Adsorption and desorption of arsenic species were not completely reversible in the column experiment. It was also found that As(V) in the column experiment was adsorbed more rapidly on soil than in the batch experiment.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1101-1106
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• 2000

When top down method is used, it could be a construction method trouble in column joint, between the former concrete and the latter. It could bring a void and weak concrete in column. The purpose of this study is to find a solution of removing void and air, way to exhaust air in top down column. through specimen concrete placing experiment.

• Journal of the Korean Society of Physical Medicine
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• v.1 no.1
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• pp.23-36
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• 2006

Purpose : The purpose of this study was to evaluate the effects of back muscle stretching on the flexibility of spinal column. Methods : The subjects were consisted of healthy adults (18 of females, 22 males ; mean aged 21.83) from 18 to 29. All subjects randomly assigned to the control group, back muscle stretching group. back muscle stretching group received back muscles stretching for 20 minutes per day and 3 times a week during 3 week period. Spine motion analyzer (Spinal Mouse) was used to measure the flexibility of spinal column. All measurement of each subjects were measured at pre-experiment, after 10 days, and after 21 days. Results : The results of this study were summarized below 1. The sacral tilt angle of the hip joint of control group, back muscle stretching group was no significantly differences at pre-experiment and after 10 days(p>0.5), but differency of each group occurred at after 21 days(p<0.5). the sacral tilt angle significantly increased at the back muscle stretching group rather than the control group. 2. The thoracic vertebral tilt angle of the control group, back muscle stretching group was no significantly differences at pre-experiment, after 10 days, after 21 days(p>0.5). 3. The lumbar vertebral tilt angle of the control group, back muscle stretching group was no significantly differences at pre-experiment, after 10 days, after 21 days(p>0.5). 4. The spinal tilt angle of control group, back muscle stretching group was no significantly differences at pre-experiment and after 10 days(p>0.5), but differency of each group occurred at after 21 days(p<0.5). the spinal tilt angle significantly increased at the back muscle stretching group rather than the control group(p>0.5). 5. The length of the spinal column of control group, back muscle stretching group was no significantly differences at pre-experiment and after 10 days (p>0.5), but differency of each group occurred at after 21 days(p<0.5). the length of the spinal column significantly increased at the back muscle stretching group rather than the control group(p<0.5). Conclusion : These data suggests that 3-week back muscle stretching improved the flexibility of sacrum, spinal column, and also improved spinal column lengthening. Additional randomized controlled trials to more fully investigate treatment effects and factors that may mediate these effects are needed.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.12 no.1
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• pp.1-15
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• 2006

Purpose: The purpose of this study was to evaluate the effects of abdominal muscle strengthening exercises and back muscle stretching on the flexibility of spinal column. Methods: The subjects were consisted of healthy adults ( 28 of females, 32 males; mean aged 21.6) from 18 to 29. All subjects randomly assigned to the control group, back muscle stretching group, abdominal muscle strengthening exercises group. back muscle stretching group received back muscles stretching for 20 minutes, abdominal muscle strengthening exercises group received abdominal muscle strengthening exercises for 30 minutes per day and 3 times a week during 3 week period. Spine motion analyzer (Spinal Mouse) was used to measure the flexibility of spinal column. All measurement of each subjects were measured at pre-experiment, after 10 days, and after 21 days. Results: The results of this study were summarized below 1. The sacral tilt angle of the hip joint of control group, back muscle stretching group, abdominal strengthening exercises group was no significantly differences at pre-experiment and after 10 days(p>0.5), but differency of each group occurred at after 21 days(p<0.5). the sacral tilt angle significantly increased at the back muscle stretching group, abdominal muscle strengthening exercises group, rather than the control group. 2. The thoracic vertebral tilt angle of the control group, back muscle stretching group, abdominal muscle strengthening exercises group was no significantly differences at pre-experiment, after 10 days, after 21 days(p>0.5). 3. The lumbar vertebral tilt angle of the control group, back muscle stretching group, abdominal muscle strengthening exercises group was no significantly differences at pre-experiment, after 10 days, after 21 days(p>0.5). 4. The spinal tilt angle of control group, back muscle stretching group, abdominal muscle strengthening exercises group was no significantly differences at pre-experiment and after 10 days(p>0.5), but differency of each group occurred at after 21 days(p<0.5). the spinal tilt angle significantly increased at the back muscle stretching group, abdominal muscle strengthening exercises group, rather than the control group(p<0.5). 5. The length of the spinal column of control group, back muscle stretching group, abdominal muscle strengthening exercises group was no significantly differences at pre-experiment and after 10 days (p>0.5), but differency of each group occurred at after 21 days(p<0.5). the length of the spinal column significantly increased at the back muscle stretching group, abdominal muscle strengthening exercises group, rather than the control group(p<0.5). Conclusion: these data suggests that 3-week abdominal muscle strengthening exercises and back muscle stretching improved the flexibility of sacrum, spinal column, and also improved spinal column lengthening. Additional randomized controlled trials to more fully investigate treatment effects and factors that may mediate these effects are needed.

• Journal of environmental and Sanitary engineering
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• v.17 no.2
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• pp.79-84
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• 2002

This study investigated possibility of the nitrification and denitrification in one counter-current column with the growth of biofilm attached to its media. This experiment was performed through use of the lab scale reactor composed of the column and settler. The column used was packed with the small size of plastic rings called PALL($1.5{\times}1.5{\;}cm$) with a cylindrical shape. Synthetic wastewater was used in the experiment. The loading rates of carbon (C) and total nitrogen (TN) furnished to the reactor were 0.23 to 1.0 kg COD/m3.d and 0.023 to 1.0 kg N/m3.d, respectively. Major factors controlling the removal efficiencies of COD and TN were the different air flux and volumetric loading rates of COD and TN. The experimental results obtained from this study demonstrated that the removal efficiencies of COD ranged from 90 to 95% and those of TN were from 80 to 83% under the N loading rate of 0.035 and $0.058{\;}kg{\;}N/m^3{\cdot}d$, respectively. The patterns of TN removed were distinctively different on the limit of 50cm of column in depth. This indicated that the nitrification and denitrification occurred near the surface zone of and inside the biofilm respectively, upto the 50cm of the column in depth.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.263-270
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• 2016

Recent Engineered nanoparticles were increasingly exposed to environmental system with the wide application and production of nanomaterials, concerns are increasing about their environmental risk to soil and groundwater system. In order to assess the transport behavior of silver nanoparticles (AgNPs), a saturated packed column experiments were examined. Inductively coupled plasma-mass spectrometry and a DLS detector was used for concentration and size measurement of AgNPs. The column experiment results showed that solution chemistry had a considerable temporal deposition of AgNPs on the porous media of solid glass beads. In column experiment, comparable mobility improvement of AgNPs were observed by changing solution chemistry conditions from salts (in both NaCl and $CaCl_2$ solutions) to DI conditions, but in much lower ionic strength (IS) with $CaCl_2$. Additionally, the fitted parameters with two-site kinetic attachment model form the experimental breakthrough curves (BTCs) were associated that the retention rates of the AgNPs aggregates were enhanced with increasing IS under both NaCl and $CaCl_2$ solutions.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.220-223
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• 2002

This study investigated a lab-scale inducing method for efficient astaxanthin accumulation. As a model system. Haematococcus pluvialis was cultivated in 2 liter bubble-column photobioreactors. The astaxanthin - inducing results using high light irradiation were compared with that of the control experiment under standard irradiation (40 ${\mu}E/m^2/s$). After the late linear growth phase (> 20 days). high light energy (230 ${\mu}E/m^2/s$) was supplied to the culture broth for astaxanthin induction. As a result. the dr γ cell weight and the astaxanthin productivity were increased up to 68% and 215%, respectively. higher than those of the control experiment. This result indicates that bubble-column type photobioreactor is a good candidate for mass cultivation of H. pluvialis and high light irradiation is an efficient induction method for astaxanthin accumulation in lab-scale bubble-column photobioreactors.

• Nuclear Engineering and Technology
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• v.34 no.1
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• pp.1-8
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• 2002

After kaolin clay was artificially contaminated with Co$^{2+}$ ion, the remediation characteristics were analyzed by the electrokinetic method. Ethanoic buffer was injected in the soil column and $CH_3$COOH was continuously inputted to the cathode reservoir to restrain the pH increase. Since the pH of the cathode side of the soil column was 4.0 initially and increased to only 6.5 after remediation for 43.6 hours, precipitate, Co(OH)$_2$, was not formed in the column. The effluent rate increased with the passage of time and Co$^{2+}$ removal in the column at the initial time were mainly controlled by ion migration. 13.1% of the total amount of Co$^{2+}$ in the soil column was removed in 10 hours, 46.8% of the total Co$^{2+}$ in 20.8 hours, 71.7% of the total Co$^{2+}$ in 30.1 hours, and 94.6% of the total Co$^{2+}$ in 43.6 hours. Meanwhile, residual concentrations in the column calculated by the developed model were similar to those by experiment. experiment.