• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.29-33
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• 2004

This study was carried out to find out safety disposal methods of waste CCA treated wood. The heavy metals of remnant were analyzed after combustion of CCA treated wood at different temperatures. Arsenic volatilized temperature was detected. The removal rate of heavy metals by acid in the ash were examined. Through this study, we could conclude that in order to protect volatilize arsenic, combustion of CCA treated wood should be do under the $300^{\circ}C$. But when CCA treated wood combustion under $300^{\circ}C$, it's weight-loss rate was $55\%$, so land reclamation dependence will be increased. When CCA treated wood combustion at high temperature, the land reclamation dependence could be reduced, but the arsenic that volatilize into the atmosphere should be captured. When it bums with high temperature, the ash contains lots of copper and chromium, so removal of heavy metals should be conducted.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.73-80
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• 2007

This study was carried out to separate the heavy toxic metals in eco-building materials by low-temperature pyrolysis, especially arsenic (As) compounds in CCA wood preservative as a solid in char. The pyrolysis was carried out to heat the CCA-treated Hemlock at $280^{\circ}C$, $300^{\circ}C$, $320^{\circ}C$, and $340^{\circ}C$ for 60 mins. Laboratory scale pyrolyzer composed of [preheater$\rightarrow$pyrolyzer$\rightarrow$1st water scrubber$\rightarrow$2nd bubbling flask with 1% $HNO_3$ solution$\rightarrow$vent], and was operated to absorb the volatile metal compound particulates at the primary water scrubber and the secondary nitric acid bubbling flask with cooling condenser of $4^{\circ}C$ under nitrogen stream of 20 mL/min flow rate. And the contents of copper, chromium and arsenic compounds in its pyrolysis such as carbonized CCA treated wood, 1st washing and 2nd washing liquors as well as its raw materials, were determined using ICP-AES. The results are as follows : 1. The yield of char in low-temperature pyrolysis reached about 50 percentage similar to the result of common pyrolytic process. 2. The higher the pyrolytic temperature was, the more the volatiles of CCA, and in particular, the arsenic compounds were to be further more volatile above $320^{\circ}C$, even though the more repetitive and sequential monitorings were necessary. 3. More than 85 percentage of CCA in CCA-treated wood was left in char in such low-temperature pyrolytic condition at $300^{\circ}C$. 4. Washing system for absorption of volatile CCA in this experiment required much more contacting time between volatile gases and water to prevent the loss of CCA compounds, especially the loss of arsenic compound. 5. Therefore, more complete recovery of CCA components in CCA-treated wood required the lower temperature than $320^{\circ}C$, and the longer contacting time of volatile gases and water needed the special washing and recovery system to separate the toxic and volatile arsenic compounds in vent gases.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.4
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• pp.105-110
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• 2012

The CCA (canonical correlation analysis) is a well known analysis tool that measures the linear relationship between two variable sets and it can be used for blind source separation (BSS). In previous works, a blind source separation scheme based on the CCA and auto regression was proposed. Unfortunately, the proposed scheme requires high signal-to-noise ratio for successful source separation. In this paper, we propose an improved BSS scheme based on the CCA and auto regression by eliminating the main diagonal elements of auto covariance matrix. Compared to the previously proposed BSS scheme, the proposed BSS scheme not only offers better source separation performance but also requires low computational complexity.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.27-34
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• 2013

This paper deals with the performance anlysis of CCA adaptive equalization algorithm, that is used for reduction of intersymbol interference at the receiving side which occurs in the time dispersive communication channel. Basically, this algorithm is borned for the solving phase unrecovery problem in the CMA equalizer, and the comines the concept of DDA (Decision Directed Algorithm) and RCA (Reduce Constellation Algorithm). The DDA has a stable convergence characteristics in unilevel signal, but not in the number of levels in multilevel signal such as QAM, so it has unstable problem. The RCA does not provide reliable initial convergence. And even after convergence, the equalization noise due to the steady state misadjustment exhibited by it is very high as compared to DDA. For the solving the abovemensioned point, the CCA adaptive eualization alogorithm has borned. In order to performance analysis of CCA algorithm, the recovered signal constellation that is the output of the equalizer, the convergence characteristic by the residual isi and MD (maximum distortion), the SER characteristic are used by computer simulation and it was compared with the DDA, RCA respectively. As a result of simulation, the DDA has superior performance than other algoithm, but it has a convergence unguarantee and unstability in the multilevel signal. In order to solving this problem, the CCA has more good performance than RCA in every performance index.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.134-146
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• 1993

A survey of the Chundong valley forest in Mt. Sobaek was conducted using 20 sample plots of 500$m^2$ size. The classification by TWINSPAN and DCA, CCA ordination techniques were applied to the study area in order to classify them into several groups based on woody plants and environmental variables. By TWINSPAN techniques, the plant community were divided into four groups. The dividing groups are Pinus densiflora community, Qurcus variabilis -Q. mongolica -P. densiflora community, Fraxinus rhynchophylla community. The successional trends of tree species by DCA ordination techniques and DBH class distribution analysis seems to be from P. densiflora through Q. mongolica. Q. variabilis to F rhynchophylla. The correlation between the score of first two axes and soil pH, soil humus, soil calcium concentration, soil magnesium concentration was significantly positive in CCA ordination. The positive correlation between the score of first two axes of F. rhynchophylla community and soil humus, soil magnesium concentration and between ones of P. densiflora community and soil pH were calculated. But there is no correlation between species and environmental variables.

• Journal of Environmental Science International
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• v.11 no.10
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• pp.1031-1037
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• 2002

CCA (Canonical Correspondence Analysis) was used so as to analyze the relation between vegetation and soil environment of Mankyeong river located in Jeollabuk-do. Vegetation survey consulted 1:5,000 topographical map, set up 30 plot and analyzed from June, 2001, to september, 2001. Plant communities of Mankyeong river was investigated by phytosocialogical method. The species composition of plant communities showed high correlation to soil pH, soil organic matter, $P_2$$O_5$, total nitrogen, EC, when they were analyed by CCA. According to the results of CCA hydrophyte communities were distributed in the region that high pH. But the vegetation of disturbed site and wetland plants were distributed in a good nutrients.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.44-49
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• 2003

This study was carried out to evaluate the weathering durability of waterborne preservative (AAC, ACQ, CCA, CuAz) treated Japanese red pine (Pinus densiflora S. et Z.) sapwood samples by accelerated weathering, and to find out the factor of stability. When considered the color changes, weight losses, surface degradation, and microstructure changes due to weathering, ACQ-, CCA-, and CuAz-treated samples were durable against weathering; the weathering durability of AAC-treated samples was poor and similar to untreated controls. The lignin content in aqueous extracts collected from ACQ-, CCA-, and CuAz-treated samples during weathering was lower than that from untreated and AAC-treated ones. From these findings, we might concluded that weathering durability of ACQ-, CCA-, and CuAz-treated samples was enhanced by the fixation of preservative component(s) onto the lignin structure, which is very susceptible to weathering.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.151-157
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• 2002

The removing copper from CCA, CCFZ treated wood were tested with Tyromyces palustris. The shacking culture, solid culture, and stationary culture methods were tested to removal of copper in CCA, CCFZ treated wood. The steam pressure method and oxalic acid method were tested as pretreatment. To investigate of copper removal mechanism, the oxalic acid that produced by T. palustris and combination with copper was examined on stationary culture that contained CCA and CCFZ treated wood chips. Oxalic acid increased copper removing rate of T. palustris as pretreatment. Stationary culture had most removal effectiveness among the culturing methods. The removal rate of copper on bioreactor was 61% on 7 days. Copper-oxalate was detected on liquid culture, which show the oxalate from liquid of culture combined with copper from treated wood. It would be related to the removal of copper from treated wood by T. palustris.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.833-844
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• 2018

Dual energy X-ray absorptiometry is mainly used as an X-ray test method. For equipment manufactured GE and Hologic, cross-calibration analyses (CCA) of machines from the same manufacturer and between units from different manufacturers have been conducted, but the CCA of equipment manufactured in Korea are inadequate. Through CCA, we present a formula of the intersections between the Korean medical equipment company (KEC) with GE and Hologic manufactured DXA, and among the KEC DXA. The CCA was conducted for the European Spine Phantom on DXA from four KEC and three global medical equipment company (GEC) manufacturers. We compared bone mineral density (BMD) values and calculated the CCA equation by linear regression analysis. The standard-deviations (SD) of the BMD values were highest for the Dexxum T for the low, medium, and high spine, which were 0.030, 0.029, and 0.037, respectively. The smallest SD in the low and medium vertebrae were 0.005 and 0.004 for the Horizon Ci, respectively, and 0.005 for the Osteo Pro Max in the high vertebrae. Based on the intersection equations of the KEC DXA established in this study, CCA of various KEC DXA should be established for more accurate follow-up of BMD tests in clinical environments.

• Korean Journal of Environment and Ecology
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• v.6 no.2
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• pp.113-126
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• 1993

To investigate the structure of the forest community of Huibang valley in Sobaeksan National Park, twenty five plots were set up and surveyed. According to the analysis of classification by DCA community divided 4 groups. The divided groups are Pinus densiflora community, Q. mongolica -P. densiflora community. Q. mongolica-Stewartia koreana-Carpinus laxiflora community, and Q. mongolica- Acer pseudosieboldianum community. In the analysis by ordination, CCA which points out the relationship among the environmental variables, species and plots indicated primary step of secondary succession. The successional trends of both techniques. seem to be from P. densiflora through Q. mongolica, Q. serrate to C. laxiflora(or S. koreana) in canopy layer below an altitude of 800 meters, and from Rhododendron mucronulaltum. Rh. schlippenbachli. Rhus trichocarpa through Styrax obassia. Lindera obtusiloba to Magnolia sieboldii, Corylus sieboldiana in subtree and shrub layer. The positive correlation between the stand ordination scores .and soil moisture and soil humus were calculated.