• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.101-107
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• 2005

One way of using wood safely and soundly for a long time is use of preservative-treated wood. Although, preservative-treated wood present to us durability and safety during using periods, it is also important to safe disposal after its service periods because of toxic components. Biological methods could be applicable to its disposal methods and better safe than chemical methods in the aspect of environmental problems. This study applied biological methods to remove the heavy metals from end-used CCA treated wood. The Aspergillus niger was used for this study which make black stain on the wood surface by it's spore. This study investigated the growing of A. niger on the CCA treated wood chips and the removal efficiency of heavy metals from CCA treated wood chips using immobilizing A. niger. A. niger could growing on the CCA treated wood chips and A. niger remove the effective elements of CCA treated wood effectively.

• Journal of IKEEE
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• v.20 no.3
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• pp.322-325
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• 2016

This paper proposed Enhanced Segmentized Clear Channel Assesment(ESCCA) for the IEEE 802.15.4 networks. This method divides original CCA into two groups to check precise channel status and perform additional CCA to increase throughput performance. Through the proposed method, the device can access the channel more often, so the transmission efficiency of the IEEE 802.15.4 network improves. To confirm the feasibility and usability of the proposed method, computer simulation has been performed. In the simulation, a star topology with one coordinator and a lot of devices is considered and the traffic flows are all one way, with the communication directed to the coordinator. Simulation results_ show the proposed method is improving maximum 10 kbps of throughput and decreasing maximum 15 of the average number of total CCA than IEEE 802.15.4 CCA method.

• The KIPS Transactions:PartC
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• v.16C no.3
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• pp.393-406
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• 2009

This paper introduces two functions added to the current version of ns-2 simulator for better accuracy of IEEE 802.15.4 network simulations. The first one is to automatically place hidden nodes over the ring topology in which the coordinator is centered, when the number of hidden nodes and total number of nodes is given. Collisions of signals can be distinguished into the trace file according to the ways of participation of hidden nodes. The second one is the CCA deferment algorithm described in IEEE 802.15.4-2006 standard which is not implemented in the current version of ns-2. Owing to these additional functions, we can carry out the precise analysis of the performance effects of hidden nodes and CCA deferment algorithm on 802.15.4 networks. Simulation results present at least 66% of performance degradation in throughput and drastic increase of collision probability up to 90% from 65% by just a single hidden node. Besides, 2006 standard for CCA deferment algorithm gives 19% lower collision probability and 38% higher performance.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.10
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• pp.139-147
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• 2015

Steady state visual evoked potential (SSVEP) has been actively studied because of its short training time, relatively higher signal-to-noise ratio, and higher information transfer rate. There are two popular analysis methods for SSVEP signals: power spectral density analysis (PSDA) and canonical correlation analysis (CCA). However, the PSDA is known to be vulnerable to noise due to the use of a single channel. Although conventional CCA is more accurate than PSDA, it may not be appropriate for the real-time SSVEP-based BCI system when it has short time window length because it uses sinusoidal signals as references. Therefore, the two methods are not efficient for the real-time BCI system that requires a short TW and a high recognition accuracy. To overcome this limitation of the conventional methods, this paper proposes a frequency recognition method with a combination of CCA and PSDA using the difference between powers of canonical variables obtained from the results of CCA. Experimental results show that the performance of the combination of CCA and PSDA is better than that of CCA for the case of a short TW.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1307-1313
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• 2015

Colangiocarcinoma (CCA) is a progressively fatal disease which generally occurs due to malignant transformation of hepatic biliary cholangiocytes. The incidence of CCA has been increasing worldwide and there is an urgent requirement for effective diagnosis and treatment strategies against this devastating disease. Different factors including liver-fluke infestation, viral hepatitis, exogenous nitrosamine-mediated DNA damage, and chronic inflammation have been linked to CCA genesis. However, the risk factors and underlying complex mechanisms leading to development of CCA are not sufficiently understood to devise an effective targeted treatment therapy. In this review, we summarize currently known epidemiological and pathological aspects of the disease and briefly describe various potential biomarkers and experimental anticancer phytochemicals related to CCA research. In addition, we also sum up recent findings that link chronic inflammation of hepatic biliary cholangiocytes with CCA. The collective information concisely presented in this article would provide useful insights into the current understanding of this cancer.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.5
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• pp.269-277
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• 2000

We propose two new types multi-stage blind clustering equalizers for QAM demoulation, which are called a complex classification algorithm(CCA) and a radial basis function algorithm(RBFA). The CCA uses a clustering technique based on the joint gaussian probability function and computes separately the real part and imaginary part for simple implementation as well as less computation. In order to improve the performance of CCA, the Dual-Mode CCA(DMCCA) incorporates the CCA tap-updating mode with the decision-directed(DD) mode. The RBFA reduces the number of cluster centers through three steps using the classification technique of RBF and then updates the equalizer taps for QAM demodulation. Test results on 16-QAM confirm that the proposed algorithms perform better the conventional multi-state equalizers in the senses of SER and MSE under multi-path fading channel.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.87-90
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• 2012

Cholangiocarcinoma (CCA) is the most common cancer in northeastern Thailand. At present, effective diagnosis of CCA either in humans or animals is not available. Monitoring the development and progression of CCA in animal models is essential for research and development of new promising chemotherapeutics. Ultrasonography has been widely used for screening of bile duct obstruction in CCA patients. In this study, we preliminarily investigated the applicability of ultrasonography to monitor the development and progression of CCA in Syrian golden hamsters (n=8) induced by Opisthorchis viverrini (OV)/dimethylnitrosamine (DMN) administration. Ultrasonography and histopathological examination of hamsters was performed at week 0, 20, 24 and 28 of OV infection or at the start of water/Tween-80 administration to controls. The ultrasonographic images of liver parenchyma and gallbladders of OV/DMN-induced CCA hamsters showed sediments in gallbladder, thickening of gallbladder wall, and hypoechogenicity of liver parenchyma cells. The ultrasonographic images of liver tissues were found to correlate well with histopathological examination. Although ultrasonography does not directly detect the occurrence of CCA, it reflects the thickening of bile ducts and abnormality of liver tissues. It may be applied as a reliable tool for monitoring the development and progression of CCA in animal models in research and development of new promising chemotherapeutics for CCA.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.53-63
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• 2005

This study attempted to obtain the basic data of utilizable possibility of preservative treated wood as a material used in a marine ranch. To evaluate the leaching stability of CCA-, CCFZ-, and ACQ-treated woods in seawater, the specimens treated with 2% and 3% (w/v) of CCA, CCFZ, and ACQ were exposed to deionized water, synthetic seawater and natural seawater for 41 days and then each component released was periodically determined. There was little amount of copper and chromium released from CCA-treated wood exposed in both deionized and seawater. Although relatively large amount of arsenic was released from CCA-treated wood, the release rate in seawater was lower than that in deionized water. The release rate of chromium and zinc from CCFZ-treated wood were somewhat greater in deionized water, but lower in seawater than in deionized water. Retention level and salinity of synthetic seawater had little effect on the release rate of components. The ACQ-treated wood had greater copper release than CCA- and CCFZ-treated wood, and the amount of copper released did not affected by leaching media used.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7473-7478
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• 2014

Cholangiocarcinoma (CCA) is a fatal cancer with poor prognosis and less than 10% of CCA patients can be offered surgical cure. Conventional chemotherapy results in unfavorable outcomes. At present, plant-derived compounds are gaining interest as potential cancer therapeutics, particularly for treatment-refractory cancers. In this study, antitumor activity of tiliacorinine, the major alkaloid isolated from a tropical plant, on CCA was first demonstrated. Antiproliferative effects of tiliacorinine on human CCA cell lines were investigated using SRB assays. Acridine orange/ethidium bromide staining, flow cytometric analysis and DNA laddering assays were used for apoptotic determination. Apoptosis-related proteins were verified by Western blotting and antitumor activity of tiliacorinine in vivo was demonstrated in CCA xenografted mice. Tiliacorinine significantly inhibited proliferation of human CCA cell lines with $IC_{50}$ $4.5-7{\mu}M$ by inducing apoptosis through caspase activation, upregulation of BAX, and downregulation of $Bcl_{xL}$ and XIAP. Tiliacorinine considerably reduced tumor growth in CCA xenografted mice. These results demonstrated antitumor effects of tiliacorinine on human CCA in vitro and in vivo. Tiliacorinine may be an effective agent for CCA treatment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4441-4446
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• 2013

Cholangiocarcinoma (CCA) is a tumor of biliary ducts, which has a high mortality rate and dismal prognosis. Constitutively activation of the transcription factor nuclear factor kappa-B (NF-${\kappa}B$) has been previously demonstrated in CCA. It is therefore a potential target for CCA treatment. Effects of diethyldithiocarbamate (DDTC) on NF-${\kappa}B$-dependent apoptosis induction in cancer have been reported; however, anti-metastasis has never been addressed. Therefore, here the focus was on DDTC effects on CCA migration and adhesiond. Anti-proliferation, anti-migration and anti-adhesion activities were determined in CCA cell lines, along with p65 protein levels and function. NF-${\kappa}B$ target gene expression was determined by quantitative RT-PCR. DDTC inhibited CCA cell proliferation. Suppression of migration and adhesion were observed prior to anti-CCA proliferation. These effects were related to decreased p65, reduction in NF-${\kappa}B$ DNA binding, and impaired activity. Moreover, suppression of ICAM-1 expression supported NF-${\kappa}B$-dependent anti-metastatic effects of DDTC. Taken together, DDTC suppression of CCA migration and adhesion through inhibition of NF-${\kappa}B$ signaling pathway is suggested from the current study. This might be a promising treatment choice against CCA metastasis.