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• Selected structural materials including SS316L, SS304L, Al, Cu and W, the self- absorption factor and detection efficiency of gamma rays were calculated to optimize the sample size. • The samples were transported to the activation terminal for irradiation, and single shot activation experiment was repeated to calculate the specific activities under a wide range of neutron fluences. • Neutron spectrum and neutron transport coefficients at the activation terminal were calculated. Subsequently, activation prediction using FIAPACT-II and comparison with experimental results were discussed. The plasma operation in the Experimental Advanced Superconducting Tokamak (EAST) would generate 2.45 MeV neutrons and a small fraction of 14 MeV neutrons. Neutrons react with structural materials, leading to the production of radioactive isotopes. The identification of nuclides and the determination of radioactive activity are of great significance for radiation protection and fusion material applications. In this study, structural materials including stainless steel 316L(SS316L), stainless steel 304L(SS304L), aluminum(Al), tungsten(W) and copper(Cu) were transported to the activation terminal for fusion neutron irradiation. The gamma ray spectra were measured using high-purity germanium (HPGe) detector, and the main radioactive nuclides of SS316L and SS304L are 56Mn, while the main radioactive nuclide of Al is 28Al. For Cu and W, the main radionuclides resulting from neutron reactions are 66Cu and 187W, respectively. The uncertainty of the radioactivity is 2.27∼7.94 % for W, 1.95∼5.84 % for SS316L, 2.10∼6.07 % for SS304L, 0.68∼1.69 % for Al and 2.59∼6.75 % for Cu. The specific activity of radionuclides is proportional to neutron yield, so the material activation is the main source of radiation dose during irradiation with high-yield neutron. The neutron activation coefficients of SS316L, SS304L, Al, Cu and W are 2.74538 × 10−14, 3.6411 × 10−14, 2.50711 × 10−12, 1.76506 × 10−12 and 3.51725 × 10−14, respectively. The coefficient represents the radioactive activity generated by each fusion neutron. In addition, the predicted activity was calculated using FISPACT program and compared with experiments. [ABSTRACT FROM AUTHOR]

Several studies have indicated that long noncoding RNAs (lncRNAs)-HOX transcript antisense RNA (HOTAIR) is involved in some cardiovascular diseases by regulating gene expression as a competitive endogenous RNA (ceRNA). GJA1 encoding Cx43 is one potential target gene of microRNA-613 (miR-613). Meanwhile, there is a potential target regulatory relationship between HOTAIR and miR-613. The present study is aimed at investigating whether HOTAIR functions as a ceRNA to regulate the Cx43 expression in atrial fibrillation (AF) by sponging miR-613. The expressions of HOTAIR, miR-613, and Cx43 were detected in the right atrial appendages of 45 patients with heart valve disease, including 23 patients with chronic AF. The HOTAIR overexpressed and underexpressed HL-1 cell model were constructed to confirm the effect of HOTAIR on Cx43. Then, the Cx43 expression was detected to testify the interplay between HOTAIR and miR-613 after cotransfecting HOTAIR and miR-613. Furthermore, luciferase assays were performed to verify that HOTAIR could regulate Cx43 remolding as a ceRNA by sponging miR-613. The expression of HOTAIR and Cx43 was significantly downregulated in chronic AF group. HOTAIR regulated positively the Cx43 expression in HL-1 cells. The upregulated effect of HOTAIR on the Cx43 expression could be remarkably attenuated by miR-613. Moreover, the inhibitory effect of miR-613 on the Cx43 expression could be obviously mitigated by HOTAIR. At last, luciferase assays confirmed HOTAIR functioned as a ceRNA in the Cx43 expression by sponging miR-613. Our study suggests that HOTAIR, functioning as a ceRNA by sponging miR-613, is an important contributor to Cx43 remolding in AF. [ABSTRACT FROM AUTHOR]

• DD/DT neutron sources were employed in the calibration of the EAST neutron activation system. • The appropriate thickness of samples should not exceed 20 mm. • The efficiency was obtained within uncertainties of 3.5%. • The fission chamber corresponds well with the neutron yield evaluated by NAS in 2018. A neutron activation system based on pneumatic transfer system has been employed to measure the time-integrated neutron yield for the Experimental Advanced Superconducting Tokamak (EAST). Those DD neutrons were detected by indium with the reaction of I n 115 (n , n ') I n 115 m , the energy threshold of the reaction was 0.3 MeV which was capable of eliminating the interference of scatting neutrons. A small amount of DT neutron generated by the deuterium plasma was detected by silicon with the reaction of S i 28 n , p A l 28 , the energy threshold was 4 MeV so as to discriminate the DD neutron from DT neutron. The γ spectrum of activated samples was obtained with high purity germanium spectrometer. The efficiency for the measurement of fusion neutrons were calibrated by DD/DT neutron accelerator. The key coefficients using to calculate the neutron flux by characteristic γ peak counts have been obtained in this calibration. Furthermore, investigation of the thickness of samples in order to cover the wide range of neutron yields was performed. The neutron activation system was implemented to the measurement of fusion neutron yield in EAST from the experiment campaign of 2018, and obtained a linear with deviation less than ± 10% comparing with fission chamber. [ABSTRACT FROM AUTHOR]

Collapse risk analysis is of great significance for ensuring construction safety in foundation pits. This study proposes a comprehensive methodology for dynamic risk analysis of foundation pit collapse during construction based on a fuzzy Bayesian network (FBN) and a fuzzy analytical hierarchy process (FAHP). Firstly, the potential risk factors contributing to foundation pit collapse are identified based on the results of statistical analysis of foundation pit collapse cases, expert inquiry, and fault tree analysis. Then, a FAHP and improved expert elicitation considering a confidence index are adopted to elicit the probability parameters of the BN. On this basis, quantitative risk reasoning and sensitivity analysis of foundation pit collapse are achieved by means of fuzzy Bayesian inference. Finally, an actual deep foundation pit in a metro station was used to illustrate a specific application of this approach, and the results were in accordance with the field observations and numerical simulation results. The proposed approach can provide effective decision-making support for planners and engineers, which is vital to the prevention and control of the occurrence of the foundation pit collapse accidents. [ABSTRACT FROM AUTHOR]

As the emissions regulations have become more stringent, reducing NOX emissions is of great importance to the shipping industry. Due to the price and emissions advantages of natural gas, the diesel-natural gas engines have become an attractive solution for engine manufacturers. Firstly, in this paper, the NOX emissions prediction model of a large marine four-stroke dual-fuel engine is built by using AVL-BOOST. In addition, the model is further calibrated to calculate the performance and emissions of the engine. Then, the influences of boost pressure, compression ratio, and the timing of intake valve closing on engine performance and emissions are analyzed. Finally, the response surface methodology is used to optimize the emissions and performance to obtain the optimal setting parameters of the engine. The results indicate that the response surface method is a highly desirable optimization method, which can save a lot of repeated research. Compared with the results from manufactured data, the power is increased by 0.55% and the BSFC, the NOX emissions, and the peak combustion pressure are decreased by 0.60%, 13.21%, and 1.51%, respectively, at low load. [ABSTRACT FROM AUTHOR]

A single crystal diamond (SCD) detector and a polycrystalline diamond (PCD) detector have been designed and fabricated using electronic grade CVD diamond. The fabricated detectors were tested for their dark current and X-ray photocurrent. It was found that the SCD and PCD detectors have superb signal to noise ratios (SNR) under X-ray irradiation from an Ag target with 10kV and 40kV accelerating voltage, 2000 and 7000 respectively for the SCD detector and 550 and 2000 for the PCD detector. The performance of these detectors using an 241Am α source was tested under different bias voltages and the results were benchmarked against a commercial SCD detector. The typical rise time of an α event in both of the fabricated detectors are about 1.2ns. The fabricated SCD detector has a 3.7% net energy resolution while that of the commercial detector is about 3.9%. The pulse height spectra are integrated and fitted to obtain the charge collection efficiency. For the fabricated SCD detector, this value is above 97% at bias 200V or beyond, which is 1-2% higher than that of the commercial detector at the same voltage. Finally, the fabricated PCD detector can also detect the presence of α particle although it only has a continuous and decreasing energy spectrum under α radiation. These results fully reveal that the fabricated SCD detector has good performance as a multifunctional detector for both X-ray and α radiation, and show great potential as neutron spectrometer as well. [ABSTRACT FROM AUTHOR]

Neutral beam injection (NBI) system has been proved to affect sawtooth activities through both producing energetic particles and supplying torque applied to the plasma. The impact of NBI on sawtooth crashes has been studied in the EAST tokamak, which is equipped with co- and counter NBIs. Statistical analysis shows that both strong co- and counter-NBI yield stronger sawtooth activities than cases when heating power is weak. A minimum sawtooth period is observed at a counter-NBI power of 0.2 MW. This is linked to zero-plasma rotation and a non-rotating precursor mode of the sawtooth instability. This indicates that the sawtooth instability is stabilized by plasma rotation as previously suggested. The fast-ion content differs between co- and counter-NBI, so energetic particles might additionally contribute to the sawtooth activities. [ABSTRACT FROM AUTHOR]

Organic and Elemental Carbon (OEC) is widely applied in the atmospheric sciences for determining carbon content and distinguishing black carbon contents of aerosols, with an advantage that OEC-based approach can provide thermograms derived from carbonaceous material. It is potential to adopt the advantage to measure the content and composition of organic carbon (OC)% in marine sediments. Here, we utilized the OEC analyzer to measure the OC% in marine sediment based on the pyrolytic oxidation principle, and obtain the OC-derived carbon dioxide (CO 2) thermograms. We examined marine sediments and reference materials to understand the stability and reproducibility of OC% measurements using our approach. The findings indicate that the OC% results (ranging from 1.44 to 1.59%, ave. 1.55 ± 0.03%, n = 64) based on this approach are accurate. In addition, CO 2 concentration thermograms obtained by repeated measurements exhibit a strong reproducibility. Our approach can thus provide the concentrations of thermally-evolved CO 2 with increasing heating temperature to deeply understand the reactivities of OC and the compositions in sediments. We suggest that the OEC-based OC% measurement is credible when samples preparation is well-performed (e.g., suitable sample mass and uniformly distributed loading). To sum up, we provide a means to accurately determine the OC% in marine sediments in terms of the ramped-pyrolysis principle. • OEC analyzer can be used for determining OC% in marine sediments. • Our methodology for determining C% of carbonaceous material is reliable. • Our approach provides a means to decipher reactivity of OC in sediments. [ABSTRACT FROM AUTHOR]

6-Gingerol (6-G) is known to alleviate myocardial ischemia/reperfusion injury. However, the underlying molecular mechanisms of 6-G myocardial protection are not known. In this study, the protective effect of 6-G on ischemia/reperfusion (I/R) damage and whether such a mechanism was related to apoptosis inhibition and activation of phosphoinositide 3-kinases (PI3K)/serine/threonine kinase (Akt) signaling pathway were investigated. Rats were subjected to I/R in the presence or absence of 6-G and the changes of cardiac function, infarct size and histopathological changes, and the levels of cardiac troponin T, creatine kinase-MB, and myocardial apoptosis were examined. The expression of caspase-3, PI3K, p-Akt, and Akt was also determined. We found that 6-G (6 mg/kg) pretreatment significantly improved heart function and ameliorated infarct size and histopathological changes and cardiac troponin T and creatine kinase-MB levels induced by I/R. Moreover, pretreatment with 6-G significantly inhibited myocardial apoptosis and caspase-3 activation induced by I/R. 6-G also upregulated expression of PI3K, p-Akt, and Akt in myocardial tissues. Taken together, these findings suggest that 6-G inhibits apoptosis and activates PI3K/Akt signaling in response to myocardial I/R injury as a possible mechanism to attenuate I/R-induced injury in heart. These results might be important for developing novel strategies for preventing myocardial I/R injury. [ABSTRACT FROM AUTHOR]

The amplitude of internal waves is an important parameter for the remote-sensing detection. However, there is no analytic method developed for the amplitude inversion of internal waves based on optical remote-sensing images. In this article, the deep-learning model is introduced to inverse the amplitude of internal waves based on a large number of optical remote-sensing images. The peak-to-peak distance and 15 types of texture characteristic parameters of images are computed, and the relationship between the amplitude of internal waves and the characteristic parameters of remote-sensing images are also investigated. In addition, based on the correlation difference between these parameters and the amplitude, three types of deep-learning model are established by selecting different parameters as input variables. Results show that the inverted amplitude of internal waves from our models shows good agreement with the in-situ data of internal waves, and the average errors between them are about 6.7%, 4.9%, and 3.6%, respectively, which indicates that the deep-learning model is effective for amplitude inversion of internal waves based on optical remote-sensing images. [ABSTRACT FROM AUTHOR]

Lightweight Network Architecture is essential for autonomous and intelligent monitoring of Unmanned Aerial Vehicles (UAVs), such as in object detection, image segmentation, and crowd counting applications. The state-of-the-art lightweight network learning based on Neural Architecture Search (NAS) usually costs enormous computation resources. Alternatively, low-performance embedded platforms and high-resolution drone images pose a challenge for lightweight network learning. To alleviate this problem, this paper proposes a new lightweight object detection model, called GhostShuffleNet (GSNet), for UAV images, which is built based on Zero-Shot Neural Architecture Search. This paper also introduces the new components which compose GSNet, namely GhostShuffle units (loosely based on ShuffleNetV2) and the backbone GSmodel-L. Firstly, a lightweight search space is constructed with the GhostShuffle (GS) units to reduce the parameters and floating-point operations (FLOPs). Secondly, the parameters, FLOPs, layers, and memory access cost (MAC) as constraints add to search strategy on a Zero-Shot Neural structure search algorithm, which then searches for an optimal network GSmodel-L. Finally, the optimal GSmodel-L is used as the backbone network and a Ghost-PAN feature fusion module and detection heads are added to complete the design of the lightweight object detection network (GSNet). Extensive experiments are conducted on the VisDrone2019 (14.92%mAP) dataset and the our UAV-OUC-DET (8.38%mAP) dataset demonstrating the efficiency and effectiveness of GSNet. The completed code is available at: https://github.com/yfq-yy/GSNet. • Design a new lightweight search space, named GS unit. • Constraints are added on parameters, FLOPs, layers, and MAC to search lighter models. • Construct a new lightweight object detection network, named GSNet. [ABSTRACT FROM AUTHOR]

• An sample-fabricated multi-parameter sensor based on the polydimethylsiloxane semi-encapsulated in-line microfiber Mach–Zehnder interferometer (MMZI) for simultaneous measurement of temperature, salinity and pressure in seawater is proposed and realized with typical sensitivities of −2312 pm/℃, 631 pm/‰, and 3775 pm/MPa, respectively. • Based on the theoretical analysis, encapsulation dependent temperature sensitivity is revealed, which is much different with those traditional MMZIs. • In signal demodulation, both sensitivity matrix method and machine learning method are used and compared with results measured by commercial conductivity-temperature-depth (CTD) system. • Using the machine learning method, accuracy of multi-parameter demodulation is improved significantly than that of sensitivity matrix method in salinity and pressure measurement. • Non-linear dependence of sensor sensitivity on surroundings is revealed, by which differences between two demodulation methods (sensitivity matrix method and machine learning method) are analyzed. Semi-encapsulated microfiber Mach-Zehnder interferometer is designed and developed for temperature, salinity and pressure (TSP) sensing in seawater. Based on the theoretical analysis, sensing experiment is performed with typical sensitivities of −2312 pm/℃, 631 pm/‰, and 3775 pm/MPa, respectively. To demodulate the signal with cross-sensitivity, sensitivity matrix method (SMM) and machine learning method (MLM) are used, respectively. By 25 tests under arbitrary TSP, relatively low errors of about 19.14 %, 4.01 % and 15.75 % are obtained based on the support vector regression (SVR) model. In addition, non-linear dependence of sensitivity on surrounding, SMM accuracy on sensing dips, stability of prediction and influence of the dataset used in training are also investigated. Finally, combination of SMM and MLM is realized, which shows relatively good performance for TSP measurement with errors of 10.67 %, 5.25 % and 16.76 %, respectively. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is one of the most common forms of cardiac arrhythmia. Novel evidence has indicated that a competing endogenous RNA (ceRNA) mechanism may occur in AF. The present study aimed to identify differentially expressed microRNAs (miRNAs/miRs) in AF and predict their targeting long non-coding RNAs (lncRNAs) to identify a potential ceRNA network involved in AF using bioinformatics analysis. The GSE68475 microarray dataset was downloaded from the Gene Expression Omnibus database and differentially expressed miRNAs in AF were obtained. In addition, right atrial appendage (RAA) tissues from patients with AF were collected to determine the expression levels of the miRNAs identified following bioinformatics analysis using reverse transcription-quantitative PCR (n=8 per group). Subsequently, Gene Ontology (GO) functional term and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analyses of the target genes of differentially expressed miRNAs of interest were performed. The potential upstream lncRNAs targeting the identified miRNAs were predicted using bioinformatics analysis. A dual luciferase reporter assay was used to verify the existence of a targeted relationship between the differentially expressed miRNA and lncRNA of interest. The results identified 43 differentially expressed miRNAs, including 23 upregulated miRNAs. The trends in the expression levels of miR-223-3p were inconsistent between the microarray data and those recorded in the RAA tissues from patients with persistent AF. Therefore, miR-223-3p was selected as the miRNA of interest for further investigations. The target gene of miR-233-3p was found to be enriched in 57 GO terms and 21 KEGG signaling pathways. According to the bioinformatics prediction, 69 lncRNAs targeting miR-223-3p were identified, including the lncRNA growth arrest-specific transcript 5, lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) and lncRNA MYC-induced long non-coding RNA. The results from dual luciferase assay confirmed that miR-223-3p was a direct target of KCNQ1OT1. A ceRNA regulatory relationship may exist between KCNQ1OT1 and miR-223-3p in AF, providing therefore a novel potential research target for further studies. [ABSTRACT FROM AUTHOR]

• After the beamlines upgrade, the plasma temperature, especially the ions temperature is substantially improved and reaches 3.2keV in the simulations which is much higher than the experimental temperature in the past. • After upgrading, the neutral beam is injected in the same direction instead of the balanced-injection. The orbit loss drops sharply by 83% and the external charge exchange loss drops by 50% after the beamline upgrade. The maximum loss share is only the shine-through loss. • After the neutral beam is upgraded, the counter-IP beam is rarely seen in the later experiments (only when the plasma is changed to clockwise). The two beamlines in the same injection direction with the plasma current leads to a significant increase of the neutron rate. The neutron rate can be as high as 4.542x1014/s in the prediction. • Due to the absence of current cancellation during balanced-injection, NBCD is greatly improved after upgrade, and the NBCD can reach 100kA which greatly reduces the Ohmic current and provides an important condition for long pulse steady-state operation. The neutral beams(NB) on EAST are being upgraded according to the scheme that the beamline located on Port F will be moved to Port D and adjusted clockwise injection to counterclockwise injection(top view), while the beamline on Port A is unchanged with counterclockwise injection. The two beamlines are modified to counterclockwise injection consistent with the direction of plasma current (co-IP) instead of the primarily balanced-injection (co-IP and counter-IP). The two coming co-IP beamlines are expected to play important roles in plasma heating, neutron emission and current drive in EAST operating scenarios. The injection performances after the beam upgrade are predicted by the simulation codes ONETWO/NUBEAM and TRANSP/NUBEAM to model the discharges on EAST. After the beamlines are upgraded, the bulk ions are heated to a high temperature above 3.2 keV, which is much higher than that in the previous experiments. The orbit loss drops sharply by 83 % and the external charge exchange loss drops by 50 % after the beamline upgrade. The neutron rate induced by the upgraded beamline is greatly enhanced to the order of 1014/s with co-IP injection as opposed to the balanced-injection, and it is also heightened with the increases of plasma density and beam power. The simulation results show that it leads to a significant improvement of the beam-driven current and provides a practical condition for EAST to carry out long pulse and steady-state experiments. The assessment on the injection capabilities of the upgraded neutral beams is an important guiding reference to the subsequent EAST experiments. [ABSTRACT FROM AUTHOR]

• The HPGe spectrometer system was placed inside the vacuum vessel to measure the characteristic γ-rays emission from radionuclides after EAST shutdown. • The identification and pathway analysis of radionuclides were discussed based on structural materials and radiation sources of EAST. • Activity of radionuclides and time evolution of dose rate, preliminary activation results, were discussed. Experimental Advanced Superconducting Tokamak (EAST) is capable of operating with long-pulse deuterium plasma, which will generate a lot of radiation such as fusion neutrons, gamma rays and hard X-rays. Since the structure material of the device was activated, work around and inside the tokamak would be limited from a radiation protection point of view after shutdown. Identification of radionuclides and evaluation of dose rate inside the vacuum vessel are needed to develop a guiding principle for radiation protection during maintenance. In this paper, a gamma ray spectrometer based on high purity germanium (HPGe) detector and digitizer was placed inside the vacuum vessel to measure the characteristic gamma ray emission from radionuclides. 7Be, 46Sc, 51Cr, 54Mn, 58Co, 60Co, 59Fe, 88Y, 91Y, 91mNb, 99Mo, 124Sb and 110mAg produced by photonuclear reactions and neutron-induced reactions were identified. The activities of radionuclides was calculated respectively with the uncertainty not exceed 6.05 %. The dose rate for 10 days after shutdown was mainly contributed by 60Co, 58Co, 54Mn, 110mAg, 59Fe, 51Cr, 88Y, 99Mo, 7Be and 124Sb, total dose rate were 3.62 × 10−9 Sv/h(Port E) and 3.40 × 10−9 Sv/h(Port I). [ABSTRACT FROM AUTHOR]

• TLDs are used for dose monitoring of tokamak device during deuterium plasma discharge. • The spatial distribution of the relative intensity of radiation dose in the EAST hall is obtained. • The variation trend of radiation dose with radial distance is obtained. • There is a certain correlation between the gamma-ray dose and neutron dose. • The monitoring results provide good data support for the establishment of the database of nuclear fusion radiation dose. The spatial distribution of relative intensity of neutron dose and gamma-ray dose in the Experimental Advanced Superconducting Tokamak (EAST) machine hall were measured by multiple thermoluminescence dosimeters (TLDs) during second experimental campaign of 2019. This activity has been performed twice, the first measurement lasted 5 days and adopted 64 pieces of dosimeters, the second time lasted 10 days and employed 100 pieces of dosimeters. These dosimeters were arranged on the ground plane outside the tokamak device with different positions to obtain the radiation dose distribution of the deuterium plasma and activated radionuclide. Generally speaking, the radiation dose decreased with the increase of radial distance. However, the measurement results of TLDs showed that the variation trends of normalized neutron dose and normalized gamma-ray dose with the increase of radial distance were unsymmetrical and not always under the attenuation law in the radial distribution of EAST ports. Some large scale of equipment and the thick concrete shielding wall had significant effect on the dose distribution. Both radiation intensity of neutron and gamma-ray raised slightly near the equipment and shielding wall in generally. Furthermore, statistics of measurements from multiple dosimeters showed that there was a certain correlation between the normalized gamma-ray dose and normalized neutron dose. [ABSTRACT FROM AUTHOR]

In recent years, deep learning models have achieved remarkable successes in various applications, such as pattern recognition, computer vision, and signal processing. However, high-performance deep architectures are often accompanied by a large storage space and long computational time, which make it difficult to fully exploit many deep neural networks (DNNs), especially in scenarios in which computing resources are limited. In this paper, to tackle this problem, we introduce a method for compressing the structure and parameters of DNNs based on neuron agglomerative clustering (NAC). Specifically, we utilize the agglomerative clustering algorithm to find similar neurons, while these similar neurons and the connections linked to them are then agglomerated together. Using NAC, the number of parameters and the storage space of DNNs are greatly reduced, without the support of an extra library or hardware. Extensive experiments demonstrate that NAC is very effective for the neuron agglomeration of both the fully connected and convolutional layers, which are common building blocks of DNNs, delivering similar or even higher network accuracy. Specifically, on the benchmark CIFAR-10 and CIFAR-100 datasets, using NAC to compress the parameters of the original VGGNet by 92.96% and 81.10%, respectively, the compact network obtained still outperforms the original networks. [ABSTRACT FROM AUTHOR]

• A plasma neutron source model based on EAST discharge shape is established. • The magnetic flux distribution describes the neutron emissivity profile. • The NSG is used for neutron emissivity and neutron energy spectrum calculations. • The calculated neutron rate agrees well with the neutron diagnostic data. Plasma neutron source is an important input for neutronics analysis of tokamak devices, and also a bridge connecting plasma physics and fusion engineering design. In order to describe the spatial distribution of plasma neutron source more accurately in tokamak device, a plasma neutron source model based on EAST plasma shape (NSM-PS) is established. The model will help to improve the reliability of neutron transport. A neutron source generator (NSG) is developed to solve the polar distribution of the neutron emissivity based on NSM-PS, and a source card file is generated which can be used directly by Monte Carlo program. The difference between the neutron source model described by the magnetic surface approximation equation and NSM-PS are analyzed in terms of neutron emissivity, neutron spectrum and neutron wall loading. Finally, the full integration of the neutron emissivity calculated by NSG in the polar direction is compared with the neutron rate measured by the neutron flux monitor, which indirectly verifies the reliability of NSM-PS. [ABSTRACT FROM AUTHOR]

A new compact stilbene crystal neutron spectrometer has been investigated and applied in the neutron emission spectroscopy on the EAST tokamak. A new components analysis method is presented to study the anisotropic light output in the stilbene crystal detector. A Geant4 code was developed to simulate the neutron responses in the spectrometer. Based on both the optimal light output function and the fitted pulse height resolution function, a reliable neutron response matrix was obtained by Geant4 simulations and validated by 2.5 MeV and 14 MeV neutron measurements at a 4.5 MV Van de Graaff accelerator. The spectrometer was used to diagnose the ion temperature in plasma discharges with lower hybrid wave injection and ion cyclotron resonance heating on the EAST tokamak. [ABSTRACT FROM AUTHOR]