• Journal of the Optical Society of Korea
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• v.18 no.2
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• pp.124-128
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• 2014

We derive joint probability density functions (JPDFs) for two adjacent data from direct-detection optical receivers in dense wavelength-division multiplexing systems. We show that the decision using two data per bit can increase the receiver sensitivity compared with the conventional decision. Our JPDFs can be used for software-defined optical receivers enhancing the receiver sensitivities for intensity-modulated channels.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.5
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• pp.428-438
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• 1987

This paper describesl the point-detector arrays system to processes the field of signal and noise of the turbulent atmosphere or variance and covariance circuit. By using the aboves, the maximum output of direct-detection shows a little differences between experimental datas. As a whole the experimental data datas are agreed with the joint Gaussian theoretical curves.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.373-376
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• 2016

The Mini Parasep SF fecal parasite concentrator (MPSFC) is a new modification of the closed concentration system, which can easily be adopted in any routine clinical pathology laboratory. Here we describe our experience with the system in diagnosing Opisthorchis viverrini. A total of 199 fecal samples was submitted for routine examination in the clinical pathology laboratory of Suranaree University of Technology hospital, Nakhon Ratchasima province, Thailand, during August to October 2015. Out of all samples examined, 10 (5.03%) were positive with intestinal parasites including O. viverrini (2.01%), followed by Strongyloided stercoralis (1.51%), Hookworm (0.5%), Taenia spp. (0.5%), and Entamoeba coli (0.5%). Regarding the distribution of intestinal parasites in relation to the methods used, and found that 4 samples (2.01%) were positive using the direct wet smear method while 10 (5.03%) were positive with the Mini Parasep SF method; the difference was statistically significant ($X^2$-test = 116.506, p-value =0.001). Mean time for processing using the Parasep system was 6.03 min/sample, the conventional direct wet smear method at 0.3 min/sample. Cost per test, conventional direct wet smear method costing less than the Parasep method at USD 0.74/sample versus USD 1.47/sample. This first report of O. viverrini detection using MPSFC indicates that Parasep concentration test is useful in the routine laboratory, increasing the yield of parasites as compared to direct microscopy, but with greater processing time and cost. Further comparisons between the Parasep concentration test and common methods for O. viverrini detection are required, particularly concerning use in epidemiological surveys.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.260-265
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• 2007

Testing a large number of samples from field monitoring and routine indexing is cumbersome and the available virus detection tools were labor intensive and expensive. To circumvent these problems we established tissue blot immunoassay (TBIA) method an alternative detection tool to detect Barley mild mosaic virus (BaMMV) and Barley yellow mosaic virus (BaYMV) infection in the field and greenhouse inoculated plants for monitoring and routine indexing applications, respectively. Initially, leaf and stem were tested to determine suitable plant tissue for direct blotting on nitrocellulose membrane. The dilutions of antibodies were optimized for more efficient and economical purposes. Results showed that stem tissue was more suitable for direct blotting for it had no background that interferes in the reaction. Therefore, this technique was referred as direct stem blot immunoassay or DSBIA, in this study. Re-used diluted (1:1000) antiserum and conjugate up to 3 times with the addition of half strength amount of concentrated antibodies was more effective in detecting the virus. The virus blotted on the nitrocellulose membrane from stem tissues kept at room temperature for 3 days were still detectable. The efficiency of DSBIA and RT-PCR in detecting BaMMV and BaYMV were relatively comparable. Results further proved that DSBIA is a rapid, reliable and economical detection method suitable for monitoring BaMMV and BaYMV infection in the field and practical method in indexing large scale of barley materials for virus resistance screening.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.4 s.334
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• pp.1-6
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• 2005

For the low power and low cost transceivers, direct sequence spread spec01m frequency-shift keying (DSSS-FSK) is proposed. A transmitter of the DSSS-FSK signal can be implemented by a simple direct modulation using the phase locked loop. Since the DSSS-FSK signal has negligible power around the carrier frequency, low cost direct conversion receiver can be used. Optimum coherent and semi-coherent correlation detection methods for the DSSS-FSK signal are proposed and analyzed. Segmented semi-coherent correlation detection method is proposed to improve the bit error rate performance in the large carrier frequency offset.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.505-509
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• 2005

For the purpose of developing a direct label-free electrochemical detection system, we have systematically investigated the electrochemical signatures of each step in the preparation procedure, from a bare gold electrode to the hybridization of label-free complementary DNA, for the streptavidin-modified electrode. For the purpose of this investigation, we obtained the following pertinent data; cyclic voltammogram measurements, electrochemical impedance spectra and square wave voltammogram measurements, in $Fe(CN)_6^{3-}/Fe(CN)_6^{4-}$ solution (which was utilized as the electron transfer redox mediator). The oligonucleotide molecules on the streptavidin-modified electrodes exhibited intrinsic redox activity in the ferrocyanide-mediated electrochemical measurements. Furthermore, the investigation of electrochemical electron transfer, according to the sequence of oligonucleotide molecules, was also undertaken. This work demonstrates that direct label-free oligonucleotide electrical recognition, based on biofunctional streptavidin-modified gold electrodes, could lead to the development of a new biosensor protocol for the expansion of rapid, cost-effective detection systems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.12
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• pp.3310-3329
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• 2023

This work designs an eighteen-channel bidirectional Intensity Modulation with Direct Detection (IM/DD) Wavelength Division Multiplexing-Passive Optical Network (WDM-PON) system. The proposed system meets the requirement of the ITU-T 5G fronthaul link suggested design in G-series Recommendations-Supplement 66. The newly designed system, with a 25Gb/s/λ data rate (450Gbps as a system capacity), has been tested and simulated using OptiSystem V.19 software. The system has been evaluated by the BER with respect to variable the optical span and CW laser power. Based on the ITU-T recommendations, the simulation results demonstrate that this system might be used as an F1 and as an Fx 5G fronthaul link for functional split choices starting from options 1 to 7a. These options are required under 25Gbps/λ for each upstream and downstream link direction. Furthermore, the proposed system utilized a bidirectional single-mode optical fiber within short optical spans of up to 10 km. The proposed system is characterized by a low-cost, simple, DSP-free and amplifier-free system with a reasonable system capacity.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.795-807
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• 2022

The development and commercialization of industrial genetically modified (GM) organisms is actively progressing worldwide, highlighting an increased need for improved safety management protocols. We sought to establish an environmental monitoring method, using real-time polymerase chain reaction (PCR) and propidium monoazide (PMA) treatment to develop a quantitative detection protocol for living GM microorganisms. We developed a duplex TaqMan quantitative PCR (qPCR) assay to simultaneously detect the selectable antibiotic gene, ampicillin (AmpR), and the single-copy Escherichia coli taxon-specific gene, D-1-deoxyxylulose 5-phosphate synthase (dxs), using a direct cell suspension culture. We identified viable engineered E. coli cells by performing qPCR on PMA-treated cells. The theoretical cell density (true copy numbers) calculated from mean quantification cycle (Cq) values of PMA-qPCR showed a bias of 7.71% from the colony-forming unit (CFU), which was within ±25% of the acceptance criteria of the European Network of GMO Laboratories (ENGL). PMA-qPCR to detect AmpR and dxs was highly sensitive and was able to detect target genes from a 10,000-fold (10^-4) diluted cell suspension, with a limit of detection at 95% confidence (LOD_95%) of 134 viable E. coli cells. Compared to DNA-based qPCR methods, the cell suspension direct PMA-qPCR analysis provides reliable results and is a quick and accurate method to monitor living GM E. coli cells that can potentially be released into the environment.

• Proceedings of the KIEE Conference
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• 2005.07d
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• pp.3019-3021
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• 2005

In this paper we suggest a novel temperature detection method utilized in direct over-temperature protection circuit modeling. The suggested model detects temperature variation using Rds(on) characteristics of MOSFET, while the conventional methods are using extra devices such as a temperature sensor or an over-temperature detection transistor. The temperature-dependant MOSFET model is implemented using Spice ABM(Spice Analog Behavior Model). The direct over-temperature protection circuit was designed including it. We verified effectiveness of the temperature dependant Rds(on) model characteristics and performance of the direct over-temperature protection circuit on PSpice simulation

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.67-75
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• 2023

Recently, many studies have been conducted on ways to utilize AI technology in NIDS (Network Intrusion Detection System). In particular, CNN-based NIDS generally shows excellent performance. CNN is basically a method of using correlation between pixels existing in an image. Therefore, the method of generating an image is very important in CNN. In this paper, the performance comparison of CNN-based NIDS according to the image generation method was performed. The image generation methods used in the experiment are a direct conversion method and a one-hot encoding based method. As a result of the experiment, the performance of NIDS was different depending on the image generation method. In particular, it was confirmed that the method combining the direct conversion method and the one-hot encoding based method proposed in this paper showed the best performance.