Multi-channel analyzer based on a novel pulse fi tting analysis method

Qingshan Wang,Xiongjie Zhang,Xiangting Meng,Bao Wang,Dongyang Wang,Pengfei Zhou,Renbo Wang,Bin Tang 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.6

A novel pulse fitting analysis (PFA) method is presented for the acquisition of nuclear spectra. Thecharging process of the feedback capacitor in the resistive feedback charge-sensitive preamplifier isequivalent to the impulsive pulse, and its impulse response function (IRF) can be obtained by non-linearfitting of the falling edge of the nuclear pulse. The integral of the IRF excluding the baseline representsthe energy deposition of the particles in the detector. In addition, since the non-linear fitting process inPFA method is difficult to achieve in the conventional architecture of spectroscopy system, a new multichannel analyzer (MCA) based on Zynq SoC is proposed, which transmits all the data of nuclear pulsesfrom the programmable logic (PL) to the processing system (PS) by high-speed AXI-Stream in order toimplement PFA method with precision. The linearity of new MCA has been tested. The spectrum of 137Cswas obtained using LaBr3(Ce) scintillator detector, and was compared with commercial MCA by ORTEC. The results of tests indicate that the MCA based on PFA method has the same performance as thecommercial MCA based on pulse height analysis (PHA) method and excellent linearity for g-rays withdifferent energies, which infers that PFA method is an effective and promising method for the acquisitionof spectra. Furthermore, it provides a new solution for nuclear pulse processing algorithms involvingregression and iterative processes

Parametric Study of Rectangular Coil for Eddy Current Testing of Lamination

Pengfei Wang,Zhiwei Zeng 한국비파괴검사학회 2016 한국비파괴검사학회지 Vol.36 No.2

Eddy current testing (ECT) is an important nondestructive testing technology for the inspection of flaws in conductive materials. However, this widely used technology is not suitable for inspecting lamination when a conventional pancake coil is used because the eddy current (EC) generated by the pancake coil is parallel to the lamination and will not be perturbed. A new method using a rectangular coil placed vertical to the work piece is proposed for lamination detection. The vertical sections of the rectangular coil induce ECs that are vertical to the lamination and can be perturbed by the lamination. A parametric study of a rectangular coil by finite element analysis was performed in order to examine the capability of generating vertical EC.

The Complete Oxidation of Ethanol at Low Temperature over a Novel Pd-Ce/γ-Al₂O₃-TiO₂ Catalyst

Wang, Yanping,Zhao, Jinshuang,Wang, Xiaoli,Li, Zhe,Liu, Pengfei Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.8

Pd-$Ce/{\gamma}-Al_2O_3-TiO_2$ catalysts were prepared by combined sol-gel and impregnation methods. Transmission electron microscopy, X-ray diffraction, $H_2$-temperature-programmed reduction, $O_2$-temperature-programmed desorption, and ethanol oxidation experiments were conducted to determine the properties of the catalysts. Addition of an optimal amount of Ce improved the performance of the $Pd/{\gamma}-Al_2O_3-TiO_2$ catalyst in promoting the complete oxidation of ethanol. The catalyst with 1% Ce exhibited the highest activity, and catalyzed complete oxidation of ethanol at $175^{\circ}C$; its selectivity to $CO_2$ reached 87%. Characterization results show that addition of appropriate amount of Ce could enrich the PdO species, and weaken the Pd-O bonds, thus enhancing oxidation ability of the catalyst. Meanwhile, the introduction of $CeO_2$ could make PdO better dispersed on ${\gamma}-Al_2O_3-TiO_2$, which is beneficial for the improvement of the catalytic oxidation activity.

A GPU-based Parallel Ant Colony Algorithm for Scientific Workflow Scheduling

Pengfei Wang,Huifang Li,Baihai Zhang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.4

Scientific workflow scheduling problem is a combinatorial optimization problem. In the real application, the scientific workflow generally has thousands of task nodes. Scheduling large-scale workflow has huge computational overhead. In this paper, a parallel algorithm for scientific workflow scheduling is proposed so that the computing speed can be improved greatly. Our method used ant colony optimization approaches on the GPU. Thousands of GPU threads can parallel construct solutions. The parallel ant colony algorithm for workflow scheduling was implemented with CUDA C language. Scheduling problem instances with different scales were tested both in our parallel algorithm and CPU sequential algorithm. The experimental results on NVIDIA Tesla M2070 GPU show that our implementation for 1000 task nodes runs in 5 seconds, while a conventional sequential algorithm implementation runs in 104 seconds on Intel Xeon X5650 CPU. Thus, our GPU-based parallel algorithm implementation attains a speed-up factor of 20.7.

Design and motion analysis of load-carrying and transmit robot (LCT-Robot) for small openings

Pengfei Wang,Qixin Cao 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.5

This paper proposes a Load-carrying and transmit robot (LCT-Robot), which is based on a novel modular joint, for the purpose of telemaintenance of the Tokamak First wall (FW). The LCT-Robot, which is installed on a Multipurpose transport cask (MTC) and plays the role of transmitting and load-carrying, has the adaptability to several of maintenance tasks by carrying different types of micro-robots. The transmission mechanism of LCT-Robot modular joint and structural "lightweight" design is comprehensively considered through establishing the geometric parameter constraint equations related to Tokamak FW. It can steadily provide the ability of long-distance transmitting and performs maintenance tasks when the weight of the micro-robot is changed. Without any gravity compensation, the LCT-Robot equipped with ordinary drive motor can bear a wide range of load. It not only satisfies the higher load, but also enhances the efficiency of the drive motor. For avoiding frequent acceleration and deceleration of the LCT-Robot, the entire process through small openings from the placement state (0-state) to the flattened state (3-state) is analyzed and the effective translational distance of MTC is confirmed. As a result, experiment verifies the effectiveness of the LCT-Robot, which has a length of 2.95 meters and can smoothly pass through small openings (Width: 200 mm, Height: 250 mm).

Heterogeneous Honeycomb-like NoC Topology and Routing based on Communication Division

Pengfei Yang,Quan Wang 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.1

Though the mostly used topologies in network-on-chip (NoC) based systems, mesh and torus can lead to a waste of resource and bandwidth when the processing elements(PEs) demand less communication, and fail to meet the requirements of PEs demanding mass communication since they connect all the PEs by the paths of the same type. In this paper, a configurable network and an efficient routing algorithm is designed so that the topology is regular and easy to expend while the adjustable density of transmission roads could satisfy the varied requirements of different PEs. Experimental results have shown that our design is more desirable in terms of network delay, power consumption and area cost among other important performance parameters of a network.

Parametric Study of Rectangular Coil for Eddy Current Testing of Lamination

Wang, Pengfei,Zeng, Zhiwei The Korean Society for Nondestructive Testing 2016 한국비파괴검사학회지 Vol.36 No.2

Eddy current testing (ECT) is an important nondestructive testing technology for the inspection of flaws in conductive materials. However, this widely used technology is not suitable for inspecting lamination when a conventional pancake coil is used because the eddy current (EC) generated by the pancake coil is parallel to the lamination and will not be perturbed. A new method using a rectangular coil placed vertical to the work piece is proposed for lamination detection. The vertical sections of the rectangular coil induce ECs that are vertical to the lamination and can be perturbed by the lamination. A parametric study of a rectangular coil by finite element analysis was performed in order to examine the capability of generating vertical EC.

The detection efficiency study of NaI(Tl) scintillation detector with the different numbers of SiPMs

Wang Bao,Zhang Xiongjie,Wang Qingshan,Wang Dongyang,Li Dong,Xiahou Mingdong,Zhou Pengfei,Ye Hao,Hu Bin,Zhang Lijiao 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.7

SiPMs are generally coupled into whole columns in gamma energy spectrum measurement, but the relationship between the distribution of whole SiPM columns and the energy resolution of the measured energy spectra is rarely reported. In this work, ∅ 3 3 inch NaI scintillator is placed on an 8 8 SiPM array, and the energy resolution of the 137Cs peak at 662 keV corresponding to the g-ray is selected as a reference. Each SiPM is switched to explore the influence of the number of SiPM arrays, distribution position, and reflective layer on the energy resolution of SiPMs. Results show that without coupling, the energy resolution is greatly improved when the number of SiPMs ranges from 4 to 32. However, after 32 slices (the area covered by SiPMs relative to the scintillator reaches 25.9%), the improvement in energy resolution and total pulse count is not obvious. In addition, the position of SiPMs relative to the scintillator does not exert much impact on the energy resolution. Results also indicate that by adding a reflective film (ESR), the energy resolution of the tested group increases by 10.38% on average. This work can provide a reference for the design and application of miniaturized SiPM gamma spectrometers

Experimental study on heat transfer characteristics of supercritical carbon dioxide natural circulation

Pengfei Wang,Peng Ding,Wenhuai Li,Rongshun Xie,Chengjie Duan,Gang Hong,Yaoli Zhang 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.3

An experimental study has been conducted to investigate the heat transfer characteristics of supercriticalcarbon dioxide (sCO2) uniformly heated in the horizontal circular smooth tube. The results illustratedthat there was a significant difference in heat transfer between the top wall and bottom wall due to thebuoyancy. Bulk flow acceleration cannot be negligible in the high heat flux region, which leads to heattransfer deterioration. A new heat transfer correlation is proposed, in which the buoyancy parameter andbulk flow acceleration have been taken into account. The new correlation and six classic correlations forsCO2 are examined in horizontal tubes. The comparison indicates that the new correlation has a betterperformance for sCO2 flowing through a horizontal heating tube under natural circulation conditions. Forexample, 94.9% of the calculated results using the new heat transfer correlation were within ±30% of theexperimental results while only 87.9% of that using the Jackson correlation (the best of the six) werewithin the same error bands.

ssc-miR-185 targets cell division cycle 42 and promotes the proliferation of intestinal porcine epithelial cell

Wang, Wei,Wang, Pengfei,Xie, Kaihui,Luo, Ruirui,Gao, Xiaoli,Yan, Zunqiang,Huang, Xiaoyu,Yang, Qiaoli,Gun, Shuangbao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: microRNAs (miRNAs) can play a role in a variety of physiological and pathological processes, and their role is achieved by regulating the expression of target genes. Our previous high-throughput sequencing found that ssc-miR-185 plays an important regulatory role in piglet diarrhea, but its specific target genes and functions in intestinal porcine epithelial cell (IPEC-J2) are still unclear. We intended to verify the target relationship between porcine miR-185 and cell division cycle 42 (CDC42) gene in IPEC-J2 and to explore the effect of miR-185 on the proliferation of IPEC-J2 cells. Methods: The TargetScan, miRDB, and miRanda software were used to predict the target genes of porcine miR-185, and CDC42 was selected as a candidate target gene. The CDC42-3' UTR-wild type (WT) and CDC42-3'UTR-mutant type (MUT) segments were successfully cloned into pmirGLO luciferase vector, and the luciferase activity was detected after co-transfection with miR-185 mimics and pmirGLO-CDC42-3'UTR. The expression level of CDC42 was analyzed using quantitative polymerase chain reaction and Western blot. The proliferation of IPEC-J2 was detected using cell counting kit-8 (CCK-8), methylthiazolyldiphenyl-tetrazolium bromide (MTT), and 5-ethynyl-2'-deoxyuridine (EdU) assays. Results: Double enzyme digestion and sequencing confirmed that CDC42-3'UTR-WT and CDC42-3'UTR-MUT were successfully cloned into pmirGLO luciferase reporter vector, and the luciferase activity was significantly reduced after co-transfection with miR-185 mimics and CDC42-3'UTR-WT. Further we found that the mRNA and protein expression level of CDC42 were down-regulated after transfection with miR-185 mimics, while the opposite trend was observed after transfection with miR-185 inhibitor (p<0.01). In addition, the CCK-8, MTT, and EdU results demonstrated that miR-185 promotes IPEC-J2 cells proliferation by targeting CDC42. Conclusion: These findings indicate that porcine miR-185 can directly target CDC42 and promote the proliferation of IPEC-J2 cells. However, the detailed regulatory mechanism of miR-185/CDC42 axis in piglets' resistance to diarrhea is yet to be elucidated in further investigation.