• Nuclear Engineering and Technology
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• v.47 no.5
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• pp.588-595
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• 2015

This study presents an effective method for additional recovery of residual actinides in liquid electrodes after the electrowinning process of pyroprocessing. The major distinctive feature of this method is a reactor with multiple reaction cells separated by partition walls in order to improve the recovery yield, thereby using the interelement difference in diffusion coefficients within the liquid electrode and controlling the selectivity and purity of element recovery. Through an example of numerical simulation of the diffusion scenarios of individual elements, we verified that the proposed method could effectively separate the actinides (U and Pu) and rare-earth elements contained in liquid cadmium. We performed a five-step consecutive recovery process using a simplified conceptual reaction cell and recovered 58% of the initial amount of actinides (U + Pu) in high purity (${\geq}99%$).

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.82-90
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• 1997

This study was conducted to establish an ideal condition for obtaining maximum extraction efficiencies using an array of soil types and under a wide variety of conditions. Nine characteristic compounds were studied: benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, n-propylbenzene, 1,2,4-trimethylbenzene, and n-butylbenzene which were found in gasoline. Increasing the moisture content resulted in decreased recovery, and recovery of hydrocarbons from wet soils was significantly lower than from dry soils. For the batch extraction process, 4 hours of extraction time was sufficient to give optimum recovery of the contaminants. With methanol as an extraction solvent, maximum recovery time appeared to be reached quicker for BTEX components than with 2-propanol. The 2 to 1 ratio of solvent/soil was chosen as a compromise to provide for the indicated minimum solvent use and high extraction efficiency. The 0.4 mg/g soil contamination was adequate to show quantitative recovery. The percent recovery of BTEX was concentration dependent more than the semivolatile compounds. Methanol and 2-propanol consistently gave higher efficiency than water. Methanol was superior to 2-propanol in removing contaminants from silty clay loam soil. Using the most efficient extraction procedure, the average recovery of the light hydrocarbons from the three soils was 66 percent. Recoveries were also dependent on soil type, solvent type, extraction time, solvent amount, contaminant concentration, and compounds volatility. This study provided a useful screening technique for procedures that can be used to remediate soils contaminated with light hydrocarbons.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.263-271
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• 2005

To compare the sedative effects using intermittent intravenous bolus injection with tiletamine-zolazepam (n = 5, TZ group), xylazine-ketamine (n = 5, XK group) and propofol (n = 5, PI group), we investigated the changes of hemodynamic (heart rate, arterial pressure), $SpO_2$, rectal temperature, respiratory rate and pain score during 60 minute sedation and 40 minute recovery period in beagle dogs. The value of rectal temperature was significantly higher in PI groups (p<0.05) during recovery period. The value of heart rate was significantly lower in XK group (p<0.05) during sedation. The changes of respiratory rate were similar tendency in all groups. The change of $SpO_2$ was stable during sedation and value was significantly higher in PI group (p<0.05) during recovery period. The value of systolic arterial pressure (SAP) was significantly lower in XK group (p<0.05) than PI group during sedation and recovery period. Low analgesic effect occurred in PI group. We concluded that intravenous anesthesia by intermittent bolus injection with propofol is useful in stabilizing rectal temperature, $SpO_2$ and hemodynamic during sedation and provide fast recovery, but have low analgesic effect.

• Journal of Chest Surgery
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• v.22 no.5
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• pp.713-723
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• 1989

In order to assess the correlation of the myocardial damage and the duration of cardiopulmonary bypass, measurement of creatine kinase [CK], lactate dehydrogenase [LDH], asparatate aminotransferase [AST], and MB band of CK [CK-MB] were carried out on the first, third, fifth, seventh, and ninth day in 44 patients following open heart surgery [POD 1,3,5,7,9]. And the patients were divided into three groups according to the duration of aortic cross clamp time [ACT]: Group I [ACT< 60 minutes. n=19], Group II [60 minutes < ACT< 90 minutes, n=7] and Group III[90 minutes > ACT, n=18]. 1. The leakage of CK in total patients increased to the highest level at POD 1, with rapid decrease and recovery at POD 7. The leakage of CK in Group III were greater than in Group I from POD 1 to POD 3 [P < 0.01]. The recovery time of CK level was shorter in Group I [POD 3] than in Group II and III [POD 7]. 2. The serum levels of LDH in total patients increased to the highest level at POD 1, with slow recovery until POD 9. The levels of LDH in Group III were higher than in Group I until POD 9 [P < 0.005]. The levels of LDH in Group I and II recovered but not in Group III. 3. The serum levels of AST in total patients increased to the highest level at POD 1, with rapid decrease and recovery at POD 7. The levels of AST in Group III were greater than in Group I from POD 1 to POD 5 [P < 0.05]. The recovery time of AST level was shorter in Group I and II [POD 5] than in Group III [POD 7]. 4. The positive cases for CK-MB in 36 patients were 22 [61.1 %] as a whole, 5[41.6%] in Group I, 4[57.1 %] in Group II, 13[76.4 %] in Group III at POD 1, and a case in each group at POD 3, and only a case in Group Ill at POD 5. It is concluded that the myocardial injury was closely related with the duration of cardiopulmonary bypass in open heart surgery.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.4
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• pp.495-502
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• 2014

Fast recovery diodes (FRDs) were developed using the $p^{{+}{+}}/n^-/n^{{+}{+}}$ epitaxial layers grown by low temperature epitaxy technology. We investigated the effect of electrostatic discharge (ESD) stresses on their electrical and switching properties using current-voltage (I-V) and reverse recovery time analyses. The FRDs presented a high breakdown voltage, >450 V, and a low reverse leakage current, < $10^{-9}$ A. From the temperature dependence of thermal activation energy, the reverse leakage current was dominated by thermal generation-recombination and diffusion, respectively, at low and high temperature regions. By virtue of the abrupt junction and the Pt drive-in for the controlling of carrier lifetime, the soft reverse recovery behavior could be obtained along with a well-controlled reverse recovery time of 21.12 ns. The FRDs exhibited excellent ESD robustness with negligible degradations in the I-V and the reverse recovery characteristics up to ${\pm}5.5$ kV of HBM and ${\pm}3.5$ kV of IEC61000-4-2 shocks. Likewise, transmission line pulse (TLP) analysis reveals that the FRDs can handle the maximum peak pulse current, $I_{pp,max}$, up to 30 A in the forward mode and down to - 24 A in the reverse mode. The robust ESD property can improve the long term reliability of various power applications such as automobile and switching mode power supply.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.1
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• pp.127-135
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• 2013

PURPOSE: This study examined the effects of exercise of diverse intensities on the recovery of articular cartilage in osteoarthritic rats. METHODS: Over a period of four weeks, the authors applied treadmill exercise programs of diverse intensities to Sprague-Dawley rats, to which intra-articular injection of monosodium iodoacetate(MIA, 3mg/$50{\mu}l$, diluted in saline) was applied to the right knee joint to induce osteoarthritis. The four-week exercise program was not carried out with the control group(CG, n=10). Exercise programs of applicable intensities were applied to the low-intensity exercise group(LEG, n=10), moderate-intensity exercise group(MEG, n=10), and high-intensity exercise group(HEG, n=10) over the four weeks. Observations were made of morphological changes in the rats' articular cartilage, using hematoxylin and eosin stains. RESULTS: there were significant differences(p<.05) in the comparison of articular damage scores between the four groups involved. Articular cartilage damage scores were found to be significantly lower in the LEG, MEG, and HEG than in the CG, indicating that exercise helped with the recovery of cartilage. Of these latter three groups, the MEG showed the highest level of recovery, while the HEG showed the lowest. CONCLUSION: These study results suggest that exercise is effective in treating OA. They also indicate that in prescribing exercise to treat osteoarthritic patients, exercise of moderate intensity is most suitable to patients' physical conditions, rather than low or high intensity, maximizes, and so should be used to maximize the effects of therapy.

• Resources Recycling
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• v.3 no.1
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• pp.17-24
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• 1994

Recovery of precious metal values from petrochemical spent catalyst is important from the viewpoint of environmental protection and resource recycling. Two types of spent catalysts were used in this study. One used in the manufacture of ethylene contains 0.3% Pd in the alumina substrate. The other used in oil refining contains 0.3% Pt and 0.3% Re. Both spent catalysts are roasted to remove volatile matters as carbon and sulfur. Then, metallic Pd powder from Pd spent catalyst is obtained in the course of grinding, hydrochloric acid or aqua regia leaching and cementation with iron. For the recovery of Pt and Re from Pt-Re spent catalyst, Pt and Re are leached with either HCI or aqua regia, first. Metallic Pt powder is recovered from the leach solution by cementation with Fe powder. Re in sulfide form is precipitated by the addition of sodium sulfide to the solution obtained after Pt recovery. It is found that 6N HCI can be successfully used as leaching agent for both types of spent catalyst. 6N HCI is considered to be better than aqua regia in consideration of reagent and equipment cost.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1043-1048
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• 2011

In this paper, a newsynchronization technique applied to burst-mode communication is proposed. A synchronization technique is to estimate carrier frequency and phase offsets in a noisy channel environment. A fundamental problem for estimating the parameters(carrier phase and frequency offsets) in burst-mode transmission is that the ways of pursuing estimation accuracy and transmission efficiency are always trade-off. To solve this problem, a new carrier recovery technique is proposed to improve the transmission efficiency with reliable performance especially at low S/N. In the proposed technique, the synchronization parameters are first estimated based on a data-aided feed-forward estimation scheme. Then, a phase tracker using decision-directed DPLL estimates the phase offset for the data portion of the burst data. From simulation results, it shows fast synchronization with shorter preamble maintaining reasonable BER performance at low S/N.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.365-370
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• 2004

In this paper, complexity secure communication was presented. The complexity circuit is used to State-Controlled Cellular Neural Network(SC-CNN). We make a complexity circuit using SC-CNN with the N-double scroll. A complexity circuit is created by applying identical n-double scrolls with coupled method, to each cell. complexity synchronization was achieved using drive response synchronization between the transmitter and receiver about each state in the SC-CNN. From the result of the recovery signal through the demodulation method in the receiver. We shown that recovery quality in the receiver is the similar to other secure communication methods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.50-57
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• 2008

Winter season cultivation of rye as green manure for soybean have been a favorite with farmer because it could remove a risk of injury by continuous cropping and increase N uptake and yield of soybean. Effects of rye green manure on soybean N uptake, $N_2$ fixation and yield were investigated with $^{15}N$ as pot experiment in greenhouse in 2004 and field in 2005, respectively. The N derived from N fertilizer ($^{15}N$) in rye green manure increased with increasing of N fertilizer rate compared to N derived from soil. N uptake and DM yield of soybean at the pot with paddy soil was higher than those at the pot with upland soil mainly due to the increase of N uptake from paddy soil. Total $^{15}N$ recovery in soil was higher at rye green manure than no green manure because $^{15}N$ applied to rye plant was remained highly as soil organic N compared to chemical N fertilizer. $^{15}N$ recovery in soybean plant increased in proportion to amounts of N fertilizer applied to rye. The N fractions from $N_2$ fixation of soybean plant at the pot experiment in 2004 ranged from 92% to 95%, on the other hand those in field experiment in 2005 ranged from 82% to 84%. Estimation of amount of $N_2$ fixation was not different between Difference method and $^{15}N$ method in 2004 and 2005.