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Phetchabun, Thailand

Boonchui S.,Kasetsart University | Boonchui S.,Chulalongkorn University | Hutem A.,Phetchabun Rajabhat University
Journal of Physics A: Mathematical and Theoretical | Year: 2013

We present a calculation of the arrival-time probability distribution based on the extended probability, as proposed by Hartle (2008 Phys. Rev.A 78 012108). We show that two cases of the arrival-time probability distribution can be used. First, we use the path decomposition expansion to discuss a fine-grained history, for which a particle has a first crossing x = 0 at time τ. The arrival-time probability, related to the probability current, is obtained. Second, we consider that the arrival-time distribution is modeled by the first photon emitted from a two-level atom (the basic atom-laser model). The partition dynamic of this system is discussed. Each history is in the form of a coarse-grained history. We confirm that the arrival-time probability distribution computed by this method agrees with that computed via the probability of no-photon detection. Crucially, the resulting arrival-time distributions can be obtained without the restriction of the consistency condition. © 2013 IOP Publishing Ltd.

Rewrujirek J.,Kasetsart University | Hutem A.,Phetchabun Rajabhat University | Boonchui S.,Kasetsart University | Boonchui S.,Chulalongkorn University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2014

The dwell time of quantum tunneling has been derived by Steinberg (1995) [7] as a function of the relation between transmission and reflection times τt and τr, weighted by the transmissivity and the reflectivity. In this paper, we reexamine the dwell time using the extended probability approach. The dwell time is calculated as the weighted average of three mutually exclusive events. We consider also the scattering process due to a resonance potential in the long-time limit. The results show that the dwell time can be expressed as the weighted sum of transmission, reflection and internal probabilities. © 2014 Elsevier B.V.

Hutem A.,Phetchabun Rajabhat University | Boonchui S.,Kasetsart University | Boonchui S.,Chulalongkorn University
Journal of Mathematical Chemistry | Year: 2014

In this paper, we apply a simple numerical method for evaluating a correlation function of atomic density fluctuation under Gaussian random potentials. Instead of using the 6-points kernel, averaged over disorders, we use the numerical shooting method for solving the Schrödinger equation of this quantum system and directly calculate the correlation function from these solutions. Since our approach does not use complicated formulas, it requires much less computational effort when compared to Green function techniques. Finally, we show results of calculations for setting each of parameters of Gaussian random potentials. © 2014 Springer International Publishing Switzerland.

Watwiengkam N.,Khon Kaen University | Sithithaworn J.,Khon Kaen University | Duenngai K.,Phetchabun Rajabhat University | Sripa B.,Khon Kaen University | And 3 more authors.
Acta Tropica | Year: 2013

Copro-antigen detection has been advocated as a promising method for diagnosis of opisthorchiasis, particularly in people that harbored light infection or have had recent drug treatment. This study aimed to improve performance of a monoclonal antibody-based enzyme-linked immunosorbent assay (Mab-ELISA) for detection of Opisthorchis viverrini copro-antigen and assess the correlation between copro-antigen and intensity of infection. Four different treatment methods of 71 samples from the Lawa endemic area, Khon Kaen province were assessed for copro-antigen detection, namely (1) phosphate buffer saline (PBS), (2) heating (70. °C 30. min), (3) alkaline (pH 9.6 in carbonate buffer), and (4) trichloroacetic acid (TCA) treatment. Comparison of these protocols showed that the TCA method gave the best performance in discriminating O. viverrini positive and negative samples with high sensitivity (97.9%) and moderate specificity (54.2%) compared with other methods. Application of TCA-based Mab-ELISA method for antigen detection in fecal samples obtained from an endemic area of opisthorchiasis revealed that 86 of 141 samples (61.0%) were positive compared with 68 (48.2%) by PBS-based protocol, while the formalin ethyl-acetate concentration technique (FECT) yielded a positive proportion of 71.6%. Among 40 egg-negative samples confirmed by a gold standard parasitological method (FECT) from the same endemic area, 19 (47.5%) were positive by the TCA-based while only 6 (15%) were positive by PBS-based Mab-ELISA protocol. In addition, levels of antigen detection significantly correlated with intensity of infection (egg per gram feces). The results show that the improved Mab-ELISA method has high sensitivity and also quantifiable diagnosis of opisthorchiasis. © 2013 Elsevier B.V.

In this project, we purpose to evaluate a ground-state of time-independent correlation function of a particle under the harmonics oscillator Gaussian-Cosine rational symmetric double-well potential. We use the numerical shooting method, the idea of program bases on it, to solve this problem. Finally, results and calculations of the atomic density fluctuation are showed. © 2014 Artit Hutem and Piyarut Moonsri.

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