• Title/Summary/Keyword: detection technique

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Determination of Aflatoxin B1 in Rice, Barley, and Feed by Non-instrumental Immunochromatographic Strip-test and High Sensitive ELISA

  • Shim, Won-Bo;Kim, Jung-Sook;Kim, Ji-Young;Choi, Jin-Gil;Je, Jung-Hyun;Kuzmina, Nina Sergeevna;Eremin, Sergei Alexandrovich;Chung, Duck-Hwa
    • Food Science and Biotechnology
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    • v.17 no.3
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    • pp.623-630
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    • 2008
  • A non-instrumental immunochromatographic (ICG) strip-test and direct competitive enzyme-linked immunosorbent assay (DC-ELISA) for aflatoxin B1 (AFB1) determination were developed and optimized. The detection limits of ICG strip-test and DC-ELISA were 0.5 and 0.004 ng/mL, respectively, and these methods possessed a cross-reaction to aflatoxins. The results of spiked samples by both methods were coincided with the amount spiked AFB1 and the comparative analyses of 172 real samples by 2 immunoassays and high performance liquid chromatography (HPLC) showed a good agreement. Especially, the ICG strip-test is easier to perform and quicker, but less sensitivity than DC-ELISA. Both methods could analyze a high sample throughput with short time, but the sample throughput of ICG strip-test was better. Therefore, the ICG strip-test can be used as a simple, easy, non-instrumental, and fast screening technique for AFB1 determination.

DSP Embeded Hardware for Non-contact Bio-radar Heart and Respiration Rate Monitoring System (DSP를 이용한 비 접촉식 도플러 바이오 레이더 생체신호 모니터링 시스템 임베디드 하드웨어의 개발)

  • Kim, Jin-Seung;Jang, Byung-Jun;Kim, Ki-Doo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.4
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    • pp.97-104
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    • 2010
  • In this paper, we provide an embedded type non-contact bio-radar heart and respiration rate monitoring system. We implemented the rate finding algorithm into the embedded system. The high-speed and reliable real-time signal processor is then tested. To avoid null-point data loss problem, we applied quadrature demodulation. Among several other combining techniques, we suggest arctangent demodulation for quadrature channel combining and DSP is used for real-time signal processing. We also suggest DC-offset compensation technique to preserve the wanted DC components of the IQ signals for accurate demodulation while keeping the dynamic range of the ADC lower. Using Texas Instrument C6711 series DSP and external 12Bit ADC, we implemented proper elliptic digital filter and autocorrelation detection algorithm for robust commercial hand held device.

Effect of Do-In (Prunus persica L. BATSCH) Water Extract (PPE) on Concentration of Extracellular Acetylcholine in the Rat Hippocampus

  • Gong Dae-Jong;Kim Geun-Woo;Koo Byung-Soo
    • The Journal of Korean Medicine
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    • v.25 no.4
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    • pp.1-7
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    • 2004
  • Objective : This study was designed to examine the effects of orally administered Prunus persica water extract (PPE), which is used as herbal medicine, for treatment of Yu Xue (stasis of blood) and tacrine on the basal concentration of extracellular acetylcholine in the hippocampus of rats. Methods: To investigate the effects of PPE and tacrine on concentration of extracellular acetylcholine in the hippocampus of rats, the microdialysis technique, under the same experimental conditions, was used. And we used male Wistar rats which were 7 weeks of age and 210-290 g. PPE was extracted with boiling water, and the rats were anesthetized with pentobarbital Na. Their skulls were exposed and a hole was drilled for implantation of a microdialysis probe. In order to increase the recovery of acetylcholine, a probe with a long membrane was used. One day after surgery, the microdialysis probe was perfused with Ringer's solution at a flow rate of 1.5 l/min. The acetylcholine concentration in dialysis samples was measured by high-performance liquid chromatography (HPLC) with electrochemical detection. AChE activity was measured using the radiometric method, as described by Sherman. Results : The comparative effects of PPE and tacrine on hippocampal extracellular acetylcholine concentration was that these cholinesterase inhibitors produced dose-dependent increases in the extracellular acetylcholine concentration. And the effect of PPE and tacrine on rat brain AChE activity was that PPE produced maximal inhibition at 1 h after administration, when AChE activity was 44% of the intact level. AChE activity gradually recovered thereafter, and reached 78% of the intact level at 12 h after administration. Conclusion : In this study, PPE has a potent activity and a long-lasting effect on the central cholinergic system, in terms of the basal concentration of extracellular acetylcholine in the hippocampus and the AChE activity in the brain of rats. And oral administration of PPE increased dose-dependently the basal concentration of extracellular acetylcholine in the hippocampus of rats. PPE may be one of the more useful cholinesterase inhibitors for the treatment of Alzheimer's disease.

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Stock Market Forecasting : Comparison between Artificial Neural Networks and Arch Models

  • Merh, Nitin
    • Journal of Information Technology Applications and Management
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    • v.19 no.1
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    • pp.1-12
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    • 2012
  • Data mining is the process of searching and analyzing large quantities of data for finding out meaningful patterns and rules. Artificial Neural Network (ANN) is one of the tools of data mining which is becoming very popular in forecasting the future values. Some of the areas where it is used are banking, medicine, retailing and fraud detection. In finance, artificial neural network is used in various disciplines including stock market forecasting. In the stock market time series, due to high volatility, it is very important to choose a model which reads volatility and forecasts the future values considering volatility as one of the major attributes for forecasting. In this paper, an attempt is made to develop two models - one using feed forward back propagation Artificial Neural Network and the other using Autoregressive Conditional Heteroskedasticity (ARCH) technique for forecasting stock market returns. Various parameters which are considered for the design of optimal ANN model development are input and output data normalization, transfer function and neuron/s at input, hidden and output layers, number of hidden layers, values with respect to momentum, learning rate and error tolerance. Simulations have been done using prices of daily close of Sensex. Stock market returns are chosen as input data and output is the forecasted return. Simulations of the Model have been done using MATLAB$^{(R)}$ 6.1.0.450 and EViews 4.1. Convergence and performance of models have been evaluated on the basis of the simulation results. Performance evaluation is done on the basis of the errors calculated between the actual and predicted values.

Fabrication of Flexible Surface-enhanced Raman-Active Nanostructured Substrates Using Soft-Lithography

  • Park, Ji-Yun;Jang, Seok-Jin;Yeo, Jong-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.411-411
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    • 2012
  • Over the recent years, surface enhanced Raman spectroscopy (SERS) has dramatically grown as a label-free detecting technique with the high level of selectivity and sensitivity. Conventional SERS-active nanostructured layers have been deposited or patterned on rigid substrates such as silicon wafers and glass slides. Such devices fabricated on a flexible platform may offer additional functionalities and potential applications. For example, flexible SERS-active substrates can be integrated into microfluidic diagnostic devices with round-shaped micro-channel, which has large surface area compared to the area of flat SERS-active substrates so that we may anticipate high sensitivity in a conformable device form. We demonstrate fabrication of flexible SERS-active nanostructured substrates based on soft-lithography for simple, low-cost processing. The SERS-active nanostructured substrates are fabricated using conventional Si fabrication process and inkjet printing methods. A Si mold is patterned by photolithography with an average height of 700 nm and an average pitch of 200 nm. Polydimethylsiloxane (PDMS), a mixture of Sylgard 184 elastomer and curing agnet (wt/wt = 10:1), is poured onto the mold that is coated with trichlorosilane for separating the PDMS easily from the mold. Then, the nano-pattern is transferred to the thin PDMS substrates. The soft lithographic methods enable the SERS-active nanostructured substrates to be repeatedly replicated. Silver layer is physically deposited on the PDMS. Then, gold nanoparticle (AuNP) inks are applied on the nanostructured PDMS using inkjet printer (Dimatix DMP 2831) to deposit AuNPs on the substrates. The characteristics of SERS-active substrates are measured; topology is provided by atomic force microscope (AFM, Park Systems XE-100) and Raman spectra are collected by Raman spectroscopy (Horiba LabRAM ARAMIS Spectrometer). We anticipate that the results may open up various possibilities of applying flexible platform to highly sensitive Raman detection.

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Effect of Methodologies for Laser-Induced Plasma Creation on Hydrogen Sensing (레이저 유도 플라스마 생성 방법이 수소 검출에 미치는 영향)

  • Jang, Jung-Ik;Kim, Ki-Bum
    • Transactions of the KSME C: Technology and Education
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    • v.3 no.4
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    • pp.291-297
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    • 2015
  • As promising future energy source, hydrogen has been drawing much attention; however, it is easily leaked from the small gap in any storage container due to its find molecule size. In this study, Laser induced breakdown spectroscopy(LIBS) was used for hydrogen leak detection, and feasibility of the scheme was evaluated based on different way for plasma generation. Laser power of 295 mW was required for generating plasma on metal surface to measure hydrogen atomic emission while approximately 2.5 times higher laser power was needed for plasma formation directly in the hydrogen gas stream. It was shown that peak to base ratio increased linearly with increasing the concentration of hydrogen. It can be concluded that LIBS is a viable technique for hydrogen sensing when the concentration of hydrogen is less than 5%.

Signal Detection for 8 PSK and 16 QAM in EST-Based Modulation (EST기반 변조에서 8 PSK와 16 QAM 에 대한 신호 검출)

  • Kwon, Byung-Uk;Hwang, Tea-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11C
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    • pp.682-693
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    • 2011
  • Energy spreading transform (EST) based modulation is an effective technique to combat frequency-selective fading in broadband wireless communication. It performs close to the inter-symbol interference (ISI)-free matched filter bound (MFB) only at the complexity of a linear detector. Originally, EST-based modulation has been proposed for QPSK. However, to fully utilize the capacity of multipath fading channels, higher-order modulations are also necessary. In this paper, we review the EST based modulation that has originally been proposed for QPSK and discuss its extension to 8 PSK and 16 QAM. The performance of the extended system is verified through simulation in Proakis B and 8-tap fading channel. The EST based modulation for 8 PSK shows the performance which is very close to MFB and the EST based modulation for 16 QAM shows the performance gap between its receiver and MFB.

For the Acquisition of Customers' Emotional Elements in the Service Design by SOMC: Simultaneous Observation Method based on Cooperation

  • Seo, Mi-Young;Lee, Eun-Jong
    • Journal of the Ergonomics Society of Korea
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    • v.31 no.1
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    • pp.23-32
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    • 2012
  • Objective: This research proposes a methodology, which validates a grasp of the customers' emotions in the service design area. Background: As the era of service design has taken its approach, the need for a deliberate design that would reflect the customer's experience had emerged in the area of service. Therefore, a variety of methodologies has been adopted in the field of service design with the purpose of discovery of the customers' needs. Even though the importance of an emotion-sentient research of a service experience increases, its research progress remains to be inadequate in comparison to all the other areas. Method: Having had taken some resources from the emotional studies under other areas of expertise as a base, the concept of volatility of emotions has been introduced as the core element of this research, further followed by an elaboration of its special characteristics. The observation technique under Stakeholder's system: SOMC(Simultaneous Observation Method based on Cooperation) has been proposed in this study as it presents an effective way to grasp the concept of volatile emotions in contrast to the previously existent types of methodologies. Results: The SOMC rather supplements the existing research methods than substitutes the previous ones. In other words, although the existing research system allowed emotion detection, it was difficult to capture the change of momentary and fickle emotions. On the opposite, the SOMC provides a condition allowing a sufficient grasp of the customer's emotions and facilitates emotional capture. Conclusion: For that reason, it is hoped that this piece of research represents a valuable and effective approach in terms of grasping the true needs of the customers on the emotional level, which will in its turn contribute to the improvement of the service quality in the midst of a complicated service condition. Application: Moreover, the purpose of this research is that in its outcome it may serve as a sufficient contribution to the area of emotional studies within the field of service design.

Effect of Performance of Aerosol Charge Neutralizers on the Measurement of Highly Charged Particles Using a SMPS (에어로졸 중화기의 성능이 고하전 입자의 크기분포 측정에 미치는 영향)

  • Ji, Jun-Ho;Bae, Swi-Nam;Hwang, Jung-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.10
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    • pp.1498-1507
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    • 2003
  • A SMPS(scanning mobility particle sizer) system measures the number size distribution of particles using electrical mobility detection technique. An aerosol charge neutralizer, which is a component of the SMPS, is a bipolar charger using a radioactive source to apply an equilibrium charge distribution to aerosols of unknown charge distribution. However, the performance of aerosol charge neutralizers is not well known, especially for highly charged particles. In this study, the effect of the particle charging characteristics of two aerosol charge neutralizers on the measurement using a SMPS system was experimentally investigated for highly charged polydisperse particles. One has radioactive source of $^{85}$ Kr (beta source, 2 mCi) and the other has $^{210}$ Po (alpha source, 0.5 mCi). The air flow rate passing through each aerosol charge neutralizer was changed from 0.3 to 3.0 L/min. The results show that the non-equilibrium character in particle charge distribution appears as the air flow rate increases although the particle number concentration is relatively low in the range of 1.5∼2x10$^{6}$ particles/㎤. The low neutralizing efficiency of the $^{85}$ Kr aerosol charge neutralizer for highly charged particles can cause to bring an artifact in the measurement using a SMPS system. However, the performance of the $^{210}$ Po aerosol charge neutralizer is insensitive to the air flow rate.

Reproductive Biotechnologies for Improvement of Buffalo: The Current Status

  • Purohit, G.N.;Duggal, G.P.;Dadarwal, D.;Kumar, Dinesh;Yadav, R.C.;Vyas, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1071-1086
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    • 2003
  • Reproductive biotechnologies continue to be developed for genetic improvement of both river and swamp buffalo. Although artificial insemination using frozen semen emerged some decades back, there are still considerable limitations. The major problem appears to be the lack of efficient methods for estrus detection and timely insemination. Controlled breeding experiments in the buffalo had been limited and similar to those applied in cattle. Studies on multiple ovulation and embryo transfer are essentially a replica of those in cattle, however with inherent problems such as lower number of primordial follicles on the buffalo ovary, poor fertility and seasonality of reproduction, lower population of antral follicles at all stages of the estrous cycle, poor endocrine status and a high incidence of deep atresia in ovarian follicles, the response in terms of transferable embryo recovery has remained low with 0.51 to 3.0 per donor and pregnancy rates between 15 to 30%. In vitro production of buffalo embryos is a valid alternative to recovery of embryos by superovulation. This aspect received considerable attention during the past decade, however the proportion of embryos that develops to the blastocyst stage is still around 25-30% and hence the in vitro culture procedures need substantial improvement. Embryo cryopreservation procedures for direct transfer post thaw need to be developed for bubaline embryos. Nuclear transfer and embryo cloning is a technique that has received attention in various species during recent years and can be of immense value in buffaloes as they have a low rate of embryo recoveries by both in vitro and in vivo procedures. Gender pre-selection, genome analysis, gene mapping and gene transfer are a few of the techniques that have been studied to a limited extent during recent years and are likely to be included in future studies on buffaloes. Very recently, reproductive biotechnologies have been applied to feral buffaloes as well, but the results obtained so far are modest. When fully exploited they can play an important role in the preservation of endangered species.