• Journal of Sensor Science and Technology
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• v.20 no.1
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• pp.35-39
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• 2011

A disposable electrochemical immunosensor system has been developed for the detection of herbicide in aqueous samples. Disposable screen printed carbon electrodes(SPCE) were used as basic electrodes and an enzyme, horseradish peroxidase (HRP), and anti-herbicide antibodies was immobilised on to the working electrode of SPCE by using avidin-biotin coupling reactions. An herbicide-glucose oxidase conjugates have been used for the competitive immunoreaction with sample herbicides. The enzymatic reaction between the conjugated glucose oxidase and glucose added generates hydrogen peroxide, which was reduced by the peroxidase immobilised. The latter process caused an electrical current change, due to direct re-reduction of peroxidase by a direct electron transfer mechanism, which was measured to determine the herbicides in the sample. The optimal operational condition was found to be: $20\;{\mu}gl-1$ deglycosylated avidin loading to the working electrode and working potential +50 mV vs. Ag/AgCl. The total assay time was 15 min after sample addition. The detection limits for herbicides, atrazine and simazine, were found to be 3 ppb and 10 ppb, respectively.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1118-1123
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• 2009

Event-specific real-time polymerase chain reaction (PCR) detection method for genetically modified (GM) maize MIR604 was developed based on integration junction sequences between the host plant genome and the integrated transgene. In this study, 2 primer pairs and probes were designed for specific amplification of 100 and 111 bp DNA fragments from the zSSIIb gene (the maize endogenous reference gene) and MIR604. The quantitative method was validated using 3 certified reference materials (CRMs) with levels of 0.1, 1, and 10% MIR604. The method was also assayed with 14 different plants and other GM maize. No amplification signal was observed in real-time PCR assays with any of the species tested other than MIR604 maize. As a result, the bias from the true value and the relative deviation for MIR604 was within the range from 0 to 9%. Precision, expressed as relative standard deviation (RSD), varied from 2.7 to 10% for MIR604. Limits of detections (LODs) of qualitative and quantitative methods were all 0.1%. These results indicated that the event-specific quantitative PCR detection system for MIR604 is accurate and useful.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.7
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• pp.1-5
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• 2012

At the present time when the limits of the magnetic storage systems appear, the holographic data storage (HDS) devices with high data transfer rate and high recording density are emerging as attractive candidates for next-generation optical storage devices. In this paper, to effectively improve the detection performance that is degraded by the two-dimensional inter-symbol interference under the HDS channel environment and the pixel misalignment, an iterative two-dimensional equalization scheme is proposed based on the contraction mapping theorem. In order to evaluate the performance of the proposed scheme, for various holographic channel environments we measure the BER performance using computer simulation and compare the proposed one with the conventional threshold detection scheme, which verifies the superiority of the proposed scheme.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.69-74
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• 2009

Abandoned objects should be treated as possibly dangerous things for public areas until they turn out to be safe because explosive material or chemical substance is intentionally contained in them for public terrors. For large public areas such as airports or train stations, there are limits in man-power for security staffs to check all the monitors for covering the entire area under surveillance. This is the basic motivation of developing the automatic detection system for dangerous abandoned objects based on vision technology. In this research, well-known DBE is applied to stably extract background images and the HOG algorithm is adapted to discriminate between human and stuff for object classification. To show the effectiveness of the proposed system, experiments are carried out in detecting intrusion for a forbidden area and alarming for abandoned objects in a room under surveillance.

• Journal of the Korea Society of Computer and Information
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• v.4 no.3
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• pp.8-12
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• 1999

Edge detection is a key component for many modern computer vision applications. While it is certainly not the only way to identify an object, or track a feature, it can be one of the most convenient if it is done quickly and consistently. Many algorithms proposed is applied to gray level images. But. there are limits in method using only intensity information, so, many researchers has try to done research about using color information. In this paper, we propose the new edge detection method usign color information, implement the widely used algorithms and compared with them in performance. In result of experiment, we show that the proposed algorithm have better result in fine detail and shaded region of image.

• Korean Journal of Environmental Agriculture
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• v.23 no.4
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• pp.251-257
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• 2004

Analytical methods were developed to determine cyclosulfamuron residues in soil, water, rice grain and straw using high-performance liquid chromatography (HPLC) with ultraviolet absorption detection. In these methods, cyclosulfamuron was extracted with aqueous $Na_2HPO_4$/acetone and acetone/methanol mixture from soil and rice samples respectively. Liquid-liquid partition coupled with ion-associated technique, Florisil column chromatography, and solid-phase extraction (SPE) were used to separate cyclosulfamuron from interfering co-extractives prior to HPLC analysis. For water sample, the residue was enriched in $C_{18}$-SPE cartridge, cleaned up in situ, and directly subjected to HPLC. Reverse-phase HPLC under ion-suppression was successfully applied to determine cyclo-sulfamuron in sample extracts with the detection at its ${\lambda}_{max}$ (254 nm). Recoveries from fortified samples averaged $87.8{\pm}7.1%$ (n=12), $97.3{\pm}7.2%$ (n=12), $90.8{\pm}6.6%$ (n=6), and $78.5{\pm}6.7%$ (n=6) for soil, water, rice grain and straw, respectively. Detection limits of the methods were 0.004 mg/kg, 0.001 mg/L, 0.01 mg/kg and 0.02 mg/kg for soil, water, rice grain and straw samples, respectively.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.102-102
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• 2019

This study developed a HPLC analysis method for the determination of avicularin (AL) and quercitrin (QT) in Astilbe chinensis by HPLC. HPLC was performed on a Capcell Pak C18 MGII column ($4.6{\times}250mm$, $5{\mu}m$) with a gradient elution of 0.05% (v/v) trifluoroacetic acid (TFA) and acetonitrile at a flow rate of 1.0 mL/min at $30^{\circ}C$ and a UV detection wavelength of 254 nm. The analytical method was validated for its specificity, precision, accuracy, and linearity. The limits of detection and quantitation were AL 0.09 and 0.28 mg/mL, QT 0.03 and 0.09 mg/mL respectively. Calibration curves showed good linearity (AL r2 > 0.99990 and QT r2 > 0.99994), and the precision of analysis was satisfied (less than AL 0.59%, QT 0.63%). Recoveries of quantified compounds ranged from AL 100.57 to 102.08%, QT 99.94 to 100.64%. These results indicate that the developed HPLC method was applied successfully to the detection of AL and QT in A. chinensis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.3
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• pp.1119-1139
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• 2021

Among the scientific literature, it has not been possible to find a consensus on the definition of the limits or properties that allow differentiating or grouping the cyber-physical systems (CPS) and the Internet of Things (IoT). Despite this controversy the papers reviewed agree that both have become crucial elements not only for industry but also for society in general. The impact of a malware attack affecting one of these systems may suppose a risk for the industrial processes involved and perhaps also for society in general if the system affected is a critical infrastructure. This article reviews the state of the art of the application of machine learning in the automation of malware detection in cyberphysical systems, evaluating the most representative articles in this field and summarizing the results obtained, the most common malware attacks in this type of systems, the most promising algorithms for malware detection in cyberphysical systems and the future lines of research in this field with the greatest potential for the coming years.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.335-342
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• 2021

Vitamin B12 deficiency may lead to serious health issues in both infants and adults. A simple analytical method involving sample pretreatment with enzyme, followed by cyanide addition under acidic conditions; separation on an immunoaffinity column; and high-performance liquid chromatography (HPLC) was developed for the rapid detection and quantitation of vitamin B12 in powdered milk. Detection limit and powdered milk recovery were determined by quantitative analysis. The limits of detection and quantitation were 2.71 and 8.21 ㎍/L, respectively. Relative standard deviations of the intra-day and inter-day precisions varied in the ranges of 0.98%-5.31% and 2.16%-3.90%, respectively. Recovery of the analysis varied in the range of 83.41%-106.57%, suggesting that the values were acceptable. Additionally, vitamin B12 content and recovery in SRM 1849a were 54.10 ㎍/kg and 112.24%, respectively. Our results suggested that the analytical method, including the sample pretreatment step, was valid. This analytical method can be implemented in many laboratory-scale experiments that seek to save time and labor. Therefore, this study shows that immunoaffinity-HPLC/ultraviolet is an acceptable technique for constructing a reliable database on vitamin B12 in powdered milk containing starch as well as protein and/or fat in high amounts.

• International Journal of Oral Biology
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• v.46 no.4
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• pp.155-159
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• 2021

This study aimed to develop strain-specific polymerase chain reaction (PCR) primers to detect Fusobacterium hwasookii KCOM 1249^T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1256, F. hwasookii KCOM 1258, and F. hwasookii KCOM 1268 on the basis of nucleotide sequences of a gene specific to each strain. The unique genes for each F. hwasookii strain were determined on the basis of their genome sequences using Roary. The strain-specific PCR primers based on each strain-specific gene were designed using PrimerSelect. The specificity of each PCR primer was determined using the genomic DNA of the 5 F. hwasookii strains and 25 strains of oral bacterial species. The detection limit and sensitivity of each strain-specific PCR primer pair were determined using the genomic DNA of each target strain. The results showed that the strain-specific PCR primers correspond to F. hwasookii KCOM 1249^T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1258, F. hwasookii KCOM 1256/F. nucleatum subsp. polymorphum KCOM 1260, or F. hwasookii KCOM 1268/Fusobacterium sp. oral taxon 203 were developed. The detection limits of these strain-specific PCR primers ranged from 0.2 to 2 ng of genomic DNA for each target strain. The results suggest that these strain-specific PCR primers are valuable in quality control for detecting specific F. hwasookii strains.