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Genotoxicity assay and potential byproduct identification during different UV-based water treatment processes
摘要： Formation of genotoxic byproducts during different ultraviolet (UV) -related water/wastewater treatment processes (including medium pressure (MP) UV oxidation, LP UV oxidation, chlorination, biological activated carbon (BAC) treatment, H2O2 oxidation, and two or more combined processes) was investigated by Ames fluctuation test using Salmonella strains TA98 and TA100 with and without rat liver enzyme extract S9. Byproducts responsible for genotoxicity were identified. The results showed that MP UV can induce mutagenicity and LP UV treatment does not induce mutagenicity. H2O2 oxidation could degrade part of genotoxic compounds. Compared with chlorination, BAC treatment is more effective in removing genotoxicity. Mutagenicity was found mostly in samples tested with TA100 instead of TA98, especially with TA100 without S9, indicating that guanosine and/or cytosine adducts contribute to mutation or toxicological effects in MP UV treated samples. Potential genotoxic byproducts were selected, most of which were nitrogenous organic compounds with more than 10 carbon atoms. Nitrosamines and histidine were excluded from potential genotoxic candidates. The results could contribute to evaluation of mutagenicity of various UV-based water treatment processes.
关键词： nitrogenous organic compounds,genotoxic by-products,Ames test,genotoxicity,medium pressure ultraviolet (MP UV) treatment
更新于2025-09-23 15:21:01
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Nuclear Power Plant Prestressed Concrete Containment Vessel Structure Monitoring during Integrated Leakage Rate Testing Using Fiber Bragg Grating Sensors
摘要： As the last barrier of nuclear reactor, prestressed concrete containment vessels (PCCVs) play an important role in nuclear power plants (NPPs). To test the mechanical property of PCCV during the integrated leakage rate testing (ILRT), a fiber Bragg grating (FBG) sensor was used to monitor concrete strain. In addition, a finite element method (FEM) model was built to simulate the progress of the ILRT. The results showed that the strain monitored by FBG had the same trend compared to the inner pressure variation. The calculation results showed a similar trend compared with the monitoring results and provided much information about the locations in which the strain sensors should be installed. Therefore, it is confirmed that FBG sensors and FEM simulation are very useful in PCCV structure monitoring.
关键词： structure health monitoring (SHM),finite element method (FEM),integrated leakage rate test (ILRT),fiber Bragg grating (FBG),prestressed concrete containment vessel (PCCV)
更新于2025-09-23 15:21:01
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A field study on the application of distributed temperature sensing technology in thermal response tests for borehole heat exchangers
摘要： Although the enhanced thermal response test (ETRT) method has been used to determine the distribution of ground temperatures and effective thermal conductivities, there are a number of obstacles which limit the wide application of this technology in the discipline of geoengineering. In this literature, four aspects of ETRT technology were investigated: (a) acquisition of ground temperature, (b) installation of the heat exchange tubes, (c) optimization of the monitoring positions, and (d) the difference in thermal conductivity obtained by the ETRT and numerical simulation. To investigate these issues, a field trial was carried out in Heze, Shandong Province, China, and the corresponding numerical models were built. The results demonstrate that: (i) the conventional methods that infer undisturbed ground temperature using water in tubes have large errors, whereas the distributed temperature sensing (DTS) technique enables the measurement of precise temperature profiles; (ii) the thermal conductivity measured using double U-tubes reflects the soil thermal property more accurately than that for a single U-tube; (iii) it is more reasonable to install optical fibers outside the U-tube sidewall than inside the observation tube; and (iv) it is essential to quantitatively consider various interface thermal impedance when estimating ground thermal conductivities using numerical simulation.
关键词： Fiber optic sensor,Distributed temperature sensing (DTS),Ground-coupled heat pump (GCHP),Thermal conductivity,Thermal response test (TRT)
更新于2025-09-23 15:21:01
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A novel computational supplement to an IR-thermography based non-destructive test of electrofusion polyethylene joints
摘要： Electrofusion Polyethylene (PE) joints are important elements of the gas distribution networks. Unfortunately they are prone to leakage if not tested thoroughly. Our team has recently proposed a novel noncontact and IR thermal non-destructive test for these PE joints. That is, to induce a controlled heat pulse within the joint via its internal wire, and compare its thermal response with other experimental reference cases. Two gaps exist in this method due to the lack of access to a mathematical model. Firstly the pulsing duration at different initial temperatures are only determined by trial and errors. Secondly, preparing experimental reference thermal images at different joint conditions is considerably costly. Therefore, here we rigorously simulate this pulsing process to tackle both abovementioned shortcomings. We experimentally validate our simulation and report the appropriate pulsing durations between 300 K and 320 K initial temperatures. Moreover, we successfully screen a contaminated joint nondestructively.
关键词： Non destructive testing,Dynamic heat transfer,Non-contact IR test,Electrofusion polyethylene joint,IR thermal imaging
更新于2025-09-23 15:21:01
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[IEEE 2019 IEEE 4th Optoelectronics Global Conference (OGC) - Shenzhen, China (2019.9.3-2019.9.6)] 2019 IEEE 4th Optoelectronics Global Conference (OGC) - A Low-Cost Portable Optical Fiber-Based Sensor for Water Turbidity Measurement
摘要： The availability of high-resolution along-track interferometric synthetic aperture radar (ATI-SAR) data with large coverage, such as TerraSAR-X (TSX) data, motivates spaceborne ground moving target detection as an attractive alternative to conventional traffic data acquisition. In this paper, a performance analysis of ground moving targets detection by means of ATI-SAR systems and using a statistical approach is carried out on both simulated and real data. A Gaussian clutter model and a deterministic target response have been assumed. The receiver operating characteristic for the likelihood ratio test (LRT), which can be assumed as a reference best performance case, has been expressed in closed form and has been related to the deflection values, which can be exploited for assessing the improvements in the detection probability with a constant false-alarm rate. For practical applications, the performance of a generalized LRT (GLRT) has been investigated. The analysis carried out on simulated data revealed that the detection results achieved using a GLRT based on a deterministic target model are comparable with those obtained using a GLRT based on a Gaussian target model and are not significantly worse than the theoretical performance of the LRT. Finally, ground moving target detection results on TSX real data are showed.
关键词： generalized likelihood ratio test (GLRT),likelihood ratio test (LRT),Along-track interferometry (ATI),synthetic aperture radar (SAR),detection,ground moving target
更新于2025-09-23 15:19:57
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[IEEE 2019 8th International Congress on Advanced Applied Informatics (IIAI-AAI) - Toyama, Japan (2019.7.7-2019.7.11)] 2019 8th International Congress on Advanced Applied Informatics (IIAI-AAI) - Hologram Calculation, Printing, and Reconstruction Based on Light-in-Flight Recording by Holography
摘要： A method for selecting a graphical model -vector-valued stationary Gaussian time series was recently proposed by Matsuda and uses the Kullback–Leibler divergence measure to define a test statistic. This statistic was used in a backward selection procedure, but the algorithm is prohibitively expensive for large . A high degree of sparsity is not assumed. We show that reformulation in terms of a multiple hypothesis test and simulations support the reduces computation time by the assertion that power levels are attained at least as good as those achieved by Matsuda’s much slower approach. Moreover, the new scheme is readily parallelizable for even greater speed gains.
关键词： multiple hypothesis test,Kullback–Leibler divergence,vector-valued time series,Undirected graph
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 26th International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) - Hangzhou, China (2019.7.2-2019.7.5)] 2019 IEEE 26th International Symposium on Physical and Failure Analysis of Integrated Circuits (IPFA) - Practical Dynamic Laser Stimulation Technique and Code Modification: A Soft Defect Localization Approach for Microcontroller Self-Test Failures
摘要： A practical alternative for soft defect localization (SDL) and fault isolation of dynamic failures is presented. The approach utilizes an existing optical beam induced resistance change (OBIRCH) hardware without a dynamic laser stimulation (DLS) add-on kit, coupled with an exhaustive electrical sample prep step which involves code modification. The technique was proven effective in localizing failures pertaining to resistive interconnects which are rather difficult to analyze using conventional static techniques.
关键词： Self-test code,Fault isolation,Soft-defect localization,Dynamic failures,Dynamic laser stimulation
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Influence of UV light on the increase of SiN <sub/>x</sub> conductivity toward elucidation of potential induced degradation mechanism
摘要： The main type of obstacles of practical applications of quantum key distribution (QKD) network are various attacks on detection. Measurement-device-independent QKD (MDIQKD) protocol is immune to all these attacks, and thus, a strong candidate for network security. Recently, several proof-of-principle demonstrations of MDIQKD have been performed. Although novel, those experiments are implemented in the laboratory with secure key rates less than 0.1 b/s. Besides, they need manual calibration frequently to maintain the system performance. These aspects render these demonstrations far from practicability. Thus, justification is extremely crucial for practical deployment into the field environment. Here, by developing an automatic feedback MDIQKD system operated at a high clock rate, we perform a field test via deployed fiber network of 30 km total length achieving a 16.9 b/s secure key rate. The result lays the foundation for a global quantum network, which can shield from all the detection-side attacks.
关键词： measurement-device-independent quantum key distribution,automatic feedback systems,Field test
更新于2025-09-23 15:19:57
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Influence of shadow on shunt-type potential-induced degradation for crystalline Si photovoltaic modules exposed outdoors
摘要： Potential-induced degradation (PID) was observed for crystalline Si photovoltaic (PV) modules set at a PID test system constructed outdoors. It was clearly shown that partial shadow and periodical water spray during daytime accelerate PID generation. PID easily occurred just underneath the shielding plate. It was also found that when a large part of one cell in the PV module was shadowed, PID is accelerated; however, when a small part of one cell in the PV module was shadowed or when the weak light is uniformly irradiated, less PID acceleration is observed. Simulation was also carried out for discussing the influence of light irradiation. These findings suggest that UV irradiation during the PID indoor test is essential for the exact estimation of the acceleration factor of the indoor PID test.
关键词： shadow,outdoor test,UV irradiation,potential-induced degradation,crystalline Si photovoltaic modules
更新于2025-09-23 15:19:57
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Laser micro drilling of 316L stainless steel orthopedic implant: A study
摘要： It has recently been shown that there is a requirement of inclined micro hole with smooth side walls (without cracks and burr), high aspect ratio, low taper, reduced heat affected zone (HAZ) and thin recast layer on orthopedic implant. So with the aim of improving hole quality characteristics and functionality of implant a multi-objective optimization of laser micro drilling with argon as an assist gas is addressed in this study. A hybrid statistical approach based on grey relational analysis (GRA) and coefficient of variation (COV) is proposed to analyse the experimental data. The key process variables responsible for quality improvement are identified. Four statistical tests are performed to compare the hybrid and GRA approach. Further, it was found that the proposed hybrid is more superior to GRA in terms of computational time and ease of computation. It is also observed that focal point position and diode current have striking effect of hole quality. An important implication of this paper is that thin recast layer, small HAZ width and spatter area were observed, when argon was used as an assist gas.
关键词： Assist gas,Laser micro-drilling,Grey relational analysis,Coefficient of variation,Orthopedic implant,Statistical test,Eccentric holes
更新于2025-09-23 15:19:57