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1.

The scintillator detectors are recalibrated against the datasheet given by the manufacturer. Optimal and mutual dependent values of (a) high voltage at PMT (Photomultiplier Tube), (b) amplifier gain, (c) average time to count the radiation particles (set by operator), and (d) number of instances/sample number are estimated. Total 5: two versions of Central Limit Theorem (CLT), (3) industry preferred Pulse Width Saturation, (4) calibration based on MPPC coupled Gamma-ray detector, and (5) gross method are used. It is shown that the CLT method is the most optimal method to calibrate the detector and its respective electronics couple. An inverse modeling-based Computerized Tomography method is used for verification. It is shown that statistically averaging results are more accurate and precise data than mode and median if the data is not skewed and a random number of samples are used during the calibration process. It is also shown that the average time to count the radiation particle is the most important parameter affecting the optimal calibration setting for precision and accurate measurements of gamma radiation.

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Wang  Eric Ke  Wang  Fan  Kumari  Saru  Yeh  Jyh-Haw  Chen  Chien-Ming 《The Journal of supercomputing》2021,77(3):3024-3043
The Journal of Supercomputing - Accidents often occur in the earth—typhoons, floods, earthquakes, traffic accidents and so on. Whether these accidents can be timely and effectively responded...  相似文献   
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This study shows the effect of phosphotungstic acid (PWA) blended into a sulfonated poly(ether ether ketone) (SPEEK) and poly(ethylene glycol) (PEG) crosslinked membrane on the membrane's electrochemical and mechanical properties. The PWA weight percentage was varied from 0 to 50%. All of the membranes were equilibrated with water at room temperature (27 °C) and elevated temperature (60 °C), and their properties were investigated. A scanning electron microscope with energy dispersive X‐ray was used to ascertain the tungsten concentration remaining in the membrane after water treatment. A systematic decrease in tungsten concentration was seen with the increase in the initial PWA percentage. The membrane blended with 10% PWA showed the best properties, having the highest conductivity (0.11 S cm?1), mechanical strength, and chemical stability. Membranes with 10% PWA and without PWA were studied in a H2/O2 fuel cell. The membrane blended with 10% PWA gave 33% more power density than the membrane without PWA. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46667.  相似文献   
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The mobility and openness of wireless communication technologies make Mobile Healthcare Systems (mHealth) potentially exposed to a number of potential attacks, which significantly undermines their utility and impedes their widespread deployment. Attackers and criminals, even without knowing the context of the transmitted data, with simple eavesdropping on the wireless links, may benefit a lot from linking activities to the identities of patient’s sensors and medical staff members. These vulnerabilities apply to all tiers of the mHealth system. A new anonymous mutual authentication scheme for three-tier mobile healthcare systems with wearable sensors is proposed in this paper. Our scheme consists of three protocols: Protocol-1 allows the anonymous authentication nodes (mobile users and controller nodes) and the HSP medical server in the third tier, while Protocol-2 realizes the anonymous authentication between mobile users and controller nodes in the second tier, and Protocol-3 achieves the anonymous authentication between controller nodes and the wearable body sensors in the first tier. In the design of our protocols, the variation in the resource constraints of the different nodes in the mHealth system are taken into consideration so that our protocols make a better trade-off among security, efficiency and practicality. The security of our protocols are analyzed through rigorous formal proofs using BAN logic tool and informal discussions of security features, possible attacks and countermeasures. Besides, the efficiency of our protocols are concretely evaluated and compared with related schemes. The comparisons show that our scheme outperforms the previous schemes and provides more complete and integrated anonymous authentication services. Finally, the security of our protocols are evaluated by using the Automated Validation of Internet Security Protocols and Applications and the SPAN animator software. The simulation results show that our scheme is secure and satisfy all the specified privacy and authentication goals.  相似文献   
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Estimation of terrestrial water budget at global and regional scales are essential for efficient agricultural water management, flood predictions, and, hydrological modeling. In hydrological modeling, it is a challenging task to quantify the major hydrological components like runoff, evapotranspiration (ET), and total water storage (TWS) due to improper and limited availability of detailed meteorological datasets. Furthermore, there has been no consensus to answer a-decade-long critical question that a less data-intensive models can be an alternate to robust data-intensive models in data scarce conditions. This study aims at multi-model approach over the single models usage for representing the hydrological behaviour in the Kangsabati River Basin (KRB), India. It is done by applying the standard model selection criteria over various hydrological models. Two hydrological models are selected, a semi- distributed model, Variable Infiltration Capacity (VIC-3 L), and a conceptually lumped model, Identification of unit Hydrograph and Component flows from Rainfall, Evapotranspiration and Streamflow (IHACRES). Both models were calibrated against the observed daily discharge at the KRB outlet for the period of 2001–2006 and validated for 2008–2010. The results show that both VIC-3 L and IHACRES produce reasonable runoff estimates at daily and monthly time scale in the KRB. The ET estimates show that VIC-3 L and IHACRES captured the seasonal variations with the percent change of 0.4% and 6.6% respectively. As IHACRES is simpler, parsimonious, fewer parameters, and better performances, it can be useful for hydrological modeling in data-scarce regions.

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This article addresses a major hygienic issue in the dairy industry, namely biofilm removal. Response surface methodology was deployed to optimise Bacillus cereus biofilm removal conditions using serine protease. The currently practiced alkali cleaning‐in‐place (CIP) method was also optimised, and while the optimised protease CIP resulted in complete removal of biofilm cells, the reference CIP (with alkali) resulted in a reduction of 4.08 log biofilm cells/cm2 and the optimised alkali CIP resulted in a reduction of ~4.92 log biofilm cells/cm2. Furthermore, the amount of the biofilm matrix removed in the optimised protease CIP was significantly higher than that of alkali CIP. It was concluded that the optimised protease CIP has better applicability.  相似文献   
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Journal of Applied Electrochemistry - The present work is focused on the effects of graphene addition on the electrochemical performance of environmentally benign nanostructured...  相似文献   
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