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This study investigates the impact of boreal spring tropical South Atlantic surface sea temperature anomalies (TSA-SSTA)on the anticyclone over the western North Pacific (WNPAC) and the Meiyu onset date (MOD) based on reanalysis dataand numerical experiments. The results indicate an intimate linkage between the MOD and TSA-SSTA, in which warmerspring TSA-SSTA are associated with an earlier MOD and vice versa, and the underlying mechanism is identified. WarmTSA-SSTA can trigger a Gill-type response and anomalous equatorial Walker circulation, which leads to anomalousupward motion and latent heating over the Maritime Continent. This anomalous condition over the Maritime Continentstrengthens local Hadley circulation accordingly accompanied by anomalous descending motion over the western North Pacific. This descending motion reduces the local rainfall and enhances the equatorward northerly wind at a low level. Further analysis reveals that local Sverdrup positive feedback between the anomalous diabatic cooling owing to reduced rainfall and the lower-level equatorward northerly wind are critical for sustaining the well-developed anomalous WNPAC. The abundant water vapor transport embedded in the northwestern flank of the anomalous WNPAC eventually favors an earlier MOD. Atmospheric conditions corresponding to cold TSA-SSTA produce the opposite effect. The spring TSA-SSTA can therefore prominently communicate with the subsequent East Asian MOD via the aforementioned mechanism, and the spring TSA-SSTA can be interpreted as a precursor signal of the East Asian MOD., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Seamless Prediction of weather and climate is a crucial way to promote services and is characterized by multi-time scale forecasting, usually from sub-seasonal to decadal prediction (S2D), which is considered to fill the gaps between weather and climate, near-term and long-term climate prediction. Improving prediction skills for extreme weather and climate disasters will undoubtedly contribute to disaster risk reduction and the sustainable development of the monsoon regions. The latest FGOALS-f2 ensemble prediction system is a seamless prediction established in 2019—four fully coupled components of FGOALS-f2, including atmospheric, oceanic, land, and sea ice modules. The dynamic core of the atmospheric component is FV3, and the critical process of the physical processes in the atmospheric part of FGOALS-f2 is a resolved convection precipitation scheme. FGOALS-f2 prediction system achieved not only 30-year forecasts but also began operational prediction in 2020. Recently, the FGOALS-f2 outputs of the sub-seasonal to seasonal (S2S) prediction have been submitted to WWRP/WCRP S2S Phase 2 Project. The prediction products cover global and regional areas, such as ENSO, MJO, TC, Arctic Sea Ice, Tibet Plateau, and surrounding Asian monsoon regions. Some typical applications of the seamless system in the monsoon region will be introduced., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The compressed sensing (CS) model can represent the signal recovery process of a large number of radar systems. The detection problem of such radar systems has been studied in many pieces of literature through the technology of debiased least absolute shrinkage and selection operator (LASSO). While naive LASSO treats all the entries equally, there are many applications in which prior information varies depending on each entry. Weighted LASSO, in which the weights of the regularization terms are tuned depending on the entry-dependent prior, is proven to be more effective with the prior information by many researchers. In the present paper, existing results obtained by methods of statistical mechanics are utilized to derive the debiased weighted LASSO estimator for randomly constructed row-orthogonal measurement matrices. Based on this estimator, we construct a detector, termed the debiased weighted LASSO detector (DWLD), for CS radar systems and prove its advantages. The threshold of this detector can be calculated by false alarm rate, which yields better detection performance than the naive weighted LASSO detector (NWLD) under the Neyman-Pearson principle. The improvement of the detection performance brought by tuning weights is demonstrated by numerical experiments. With the same false alarm rate, the detection probability of DWLD is obviously higher than those of NWLD and the debiased (non-weighted) LASSO detector (DLD).

The mechanisms involved in the onset of the Bay of Bengal summer monsoon (BOBSM) were studied using reanalysis data and numerical model experiments. Results revealed that the weak meridional land–sea thermal contrast (LSTC) over the northern BOB in early spring enhances the lower-tropospheric easterly belt along 10°–15°N, which is unfavorable for the BOBSM onset. The BOBSM onset is driven by the cumulative impact of this LSTC along with the LSTC in the meridional direction across the equator and in the zonal direction across the tropics, together with air–sea interactions. While the LSTC intensifies over the northern BOB, a near-surface northward cross-equatorial flow develops south of India, inducing springtime zonal flow and surface sensible heating over the southern BOB and a pair of cyclones straddling the equator over the central Indian Ocean at 700 hPa. The zonal LSTC in the tropics generates near-surface cyclones over land and anticyclones over the sea. This induces a zonal SST warm pool around 10°N, which produces vertical westerly wind shear to the north and weakens the wintertime easterly aloft and the anticyclone to its north. As the cyclone over southern India develops eastward, the cyclone below 700 hPa develops northward over the eastern BOB in response to the enhancing tropical westerly and surface sensible heating. The wintertime anticyclonic belt and easterly belt split, and the southerly carries water vapor northward over the eastern BOB, heralding the onset of the BOBSM and presenting a delayed response to the springtime LSTC changes.

Near field computational imaging has been recognized as a promising technique for non-destructive and highly accurate detection of the target. Meanwhile, reconfigurable intelligent surface (RIS) can flexibly control the scattered electromagnetic (EM) fields for sensing the target and can thus help computational imaging in the near field. In this paper, we propose a near-field imaging scheme based on holograghic aperture RIS. Specifically, we first establish an end-to-end EM propagation model from the perspective of Maxwell equations. To mitigate the inherent ill conditioning of the inverse problem in the imaging system, we design the EM field patterns as masks that help translate the inverse problem into a forward problem. Next, we utilize RIS to generate different virtual EM masks on the target surface and calculate the cross-correlation between the mask patterns and the electric field strength at the receiver. We then provide a RIS design scheme for virtual EM masks by employing a regularization technique. The cross-range resolution of the proposed method is analyzed based on the spatial spectrum of the generated masks. Simulation results demonstrate that the proposed method can achieve high-quality imaging. Moreover, the imaging quality can be improved by generating more virtual EM masks, by increasing the signal-to-noise ratio (SNR) at the receiver, or by placing the target closer to the RIS.

ObjectivesIn malignant tumors, elevated infiltration of intratumoral CD8+ cytotoxic T cells predicts a beneficial prognosis, whereas high levels of CD15+ neutrophils in peritumor tissues indicate poor prognosis. It is unclear how SMAD4, which promotes favorable clinical outcomes and antitumor immunoregulation, along with CD8+ cytotoxic T cells and CD15+ neutrophils exert an influence on hypopharyngeal carcinoma (HPC).Materials and methodsSpecimens were collected from 97 patients with HPC. Immunohistological analyses of SMAD4, CD8+ cytotoxic T cell and CD15+ neutrophil expression were performed. SMAD4 nuclear intensity was measured, meanwhile, CD8+ cytotoxic T cells and CD15+ neutrophils were counted under a microscope. The prognostic role of SMAD4 was determined using the log-rank test and univariate and multivariate analyses. The relationship among SMAD4, CD8+ cytotoxic T cells, and CD15+ neutrophils was estimated by Mann–Whitney U test.ResultsHigh levels of SMAD4 were associated with favorable overall survival (OS) and disease-free survival (DFS) in HPC. Multivariate analysis suggested that SMAD4 is an independent predictor of OS and DFS. A high density of intratumoral CD8+ cytotoxic T cells and low accumulation of CD15+ neutrophils in the peritumor area were associated with longer OS and DFS. Furthermore, SMAD4 was linked to the levels of intratumoral CD8+ cytotoxic T cells and peritumoral CD15+ neutrophils. Patients with high SMAD4/high intratumoral CD8+ cytotoxic T cells or high SMAD4/low peritumoral CD15+ neutrophils showed the best prognosis.ConclusionSMAD4, CD8+ cytotoxic T cell level, and CD15+ neutrophil level have prognostic value in HPC. SMAD4 is a promising prognostic marker reflecting immune response in HPC.

Excessive precipitation was observed throughout the Yangtze River Valley during the 2020 Meiyu season. However, the mechanism of extreme precipitation over the upper reaches of the Yangtze River remains unclear. Our results show that the activities of high potential vorticity (PV) systems are responsible for the above-normal rainfall over both western and eastern China. The activity of high-PV systems is characterized by a prominent diurnal cycle, and their formation is closely related to the thermal contrast between the near-surface and lower atmosphere. In the morning, surface sensible heating increases sharply after sunrise, leading to a decrease in diabatic heating with height and weakened PV in the lower atmosphere. An increase in turbulence increases near-surface evaporation and reduces surface diabatic heating. At the same time, cloud formation increases diabatic heating at approximately 400 hPa. Consequently, the thermal contrast below 400 hPa leads to an increase in diabatic heating with height, favoring the generation of high-PV systems. Compared with the climatology, an excessive water vapor supply from the anomalous anticyclone forced by the Indian Ocean warming in 2020, contributes to a stronger thermal contrast and enhanced activity of high-PV systems over the TP. The arrival timing of high-PV systems at the eastern flank of the TP plays an important role in the subsequent development of these systems. Early arrival in the afternoon or evening is generally accompanied by air convergence and sufficient water vapor supply downstream of the TP, which favors the systems moving off the TP and influencing precipitation downstream., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Using optical microscopy and multiparticle tracking techniques, we investigate the correlated diffusion of colloidal particles over a rugged surface. Our findings demonstrate that the correlated diffusion caused by the hydrodynamic interactions of particles confined to energy landscapes displays a distinctive power-law behavior. The local energy landscape on the rugged surface reduces the long-range hydrodynamic interactions between colloidal particles. The energy landscape influences the strength of hydrodynamic interactions, but not their power-law form. The responding factor of the colloidal particles over the energy landscape to hydrodynamics decays exponentially with the potential energy minimum. We propose a scaling method, with which the correlated diffusion of colloidal particles over various energy landscapes can be scaled onto a master curve. The master curve characterizes the response of the particles over the energy landscape to the hydrodynamics. The scale factors used for the master curve allow for the calculation of the energy landscape. The findings provide physical insights into the confinement hydrodynamics and would be helpful for designing material surfaces and controlling the motion of particles on rough surfaces. Published version This work was partially supported by the Key Academic Discipline Project of China University of Mining and Technology (Grant No. 2022WLXK10), the China Scholarship Council (Grant No. 202006425022), the Basic Research Program Project of Xuzhou (Grant No. KC21020), the National Natural Science Foundation of China (Grant No. 11774417) and the Natural Science Foundation of Jiangsu Province (Grant No. BK20160238).

Flexible DC and AC transmission lines can be arranged across vertically or sharing transmission corridor. Under this condition, the possibility of intersystem fault increases significantly, which endangers the safety of both DC and AC systems. Here, the intersystem fault between bipolar half‐bridge MMC‐HVDC system and AC system is analysed. The reliability of DC wavefront protection after intersystem fault is analysed based on initial traveling wave, while the reliability of DC intersystem fault protection and AC protection is analysed based on 50 Hz component characteristics. Since wavefront protection cannot be guaranteed to operate reliably, intersystem fault protection based on 50 Hz components is applied to DC system to reliably detect intersystem faults and isolate the fault by commanding DC circuit breaker to trip. Although current differential relaying and zero‐sequence overcurrent relaying in AC system can reliably detect intersystem faults, a large DC offset prevents effective fault isolation of AC circuit breaker. This highlights the necessity of MMC‐HVDC system to reliably isolate intersystem faults.

Faced with complex engineering geological problems, the application of comprehensive geophysical prospecting technologies allows for various technical achievements to complement each other, verify each other, reduce the ambiguity in geophysical prospecting results, and improve the accuracy of geophysical prospecting interpretations. At present, comprehensive geophysical prospecting is predominantly a simple synthesis of quantification, lacks effective intelligent decision-making methods, and cannot maintain pace with the development direction of future intelligent geophysical prospecting technologies. Therefore, this study proposes a geophysical prospecting selection evaluation method based on comprehensive weights to realize the transformation from empirical to scientific decision-making. In the proposed method, four criteria—specifically, detection accuracy, technical reliability, economic rationality, and data richness level—are first selected to establish an evaluation index system. Then, analytical hierarchy process and entropy weight method are used to combine subjective experience with objective data to form a comprehensive weight for the evaluation of geophysical prospecting selection through the fuzzy evaluation method. The efficacy of the proposed method was evaluated through application to karst exploration in the limestone mining area of the Hepu in Guangxi, for which an optimal geophysical prospecting scheme, composed of electrical resistivity tomography, microtremor survey method, and cross-hole resistivity computed tomography, was obtained. The scheme realizes the asymptotic detection of karst development from coarse to fine and improves the timeliness and economics of disaster management. These results verify the effectiveness and scientific soundness of the proposed method.

Landslides are common occurrences along Chinese rail routes. Accordingly, the accurate determination of sliding-surface locations and the underlying causes become critical from the landslide-disaster-management and loss-mitigation viewpoints. In this study, the landslide in the K66 section of the Jiheng Railway (installed in Jinggangshan City, Jiangxi, China) was investigated. The causative factors and characteristics of the landslide were analyzed using geophysical methods as well as drilling and monitoring techniques. The results reveal that a combination of the transient electromagnetic method and electrical resistivity tomography can be used to identify the location of water-rich landslide-prone regions. When combined with the drilling information, these results reveal the tendency of landslide occurrence in regions comprising strongly weathered carbonaceous shale. Moreover, an uneven slope deformation is observed along the railway line. The seepage of surface water into the slope is revealed as the primary cause of landslides. This is because the reduced strength of the strongly weathered carbonaceous shale facilitates the formation of sliding surfaces. This paper presents a comprehensive survey plan for landslides occurring along railway routes. Furthermore, an assessment of the risk of future landslide occurrences in the investigation area is presented, thereby providing an appropriate reference for landslide prevention and loss mitigation.

During long-distance excavation, a tunnel boring machine (TBM) encounters boulders that affect the safety and progress of construction. To ensure the smooth progress of tunnel construction, it is necessary to delineate their locations and ranges before construction. The large resistivity difference between boulders and the surrounding medium makes the electrical resistivity tomography method capable of boulder detection. This study established different spatial boulder distribution models and analyzed the advantages and disadvantages of cross-hole resistivity tomography and surface resistivity data for boulder detection. After that, we evaluated imaging features of resistivity data fusion of these two methods based on principal component analysis. The results indicated that (1) the cross-hole resistivity tomography imaging ability near the borehole can be improved. With the addition of valid data, the surface resistivity data improved the capacity to determine peripheral geological anomalies, especially at the interfaces. (2) The resolution of the surface resistivity data in the vertical direction and the cross-hole resistivity tomography in the lateral direction has also been improved, and the ability to identify single anomalies has been enhanced. As two-dimensional (2D) profiles may not accurately locate the boulders, we proposed a three-dimensional (3D) coordinate conversion method that unifies different data to the same coordinate system. We adopted interpolation to conduct 3D imaging, thus improving the intuitiveness of the detected results. The successful application of boulder detection in the shield section of the Dalian subway proved the rationality of the method. It provided corresponding guidance and guarantees for safety construction with the TBM.

It is a fundamental problem to analyse the performance bound of multiple-input multiple-output (MIMO) dual-functional radar-communication (DFRC) systems. To this end, we derive a performance bound on the communication function under a constraint on radar performance. To facilitate the analysis, we consider a toy example, in which there is only one down-link user with a single receive antenna and one radar target. In such a simplified case, we obtain an analytical expression for the performance bound and the corresponding waveform design strategy to achieve the bound. The results reveal a tradeoff between communication and radar performance, and a condition when the transmitted energy can be shared between these two functions.

Large volumes of water originating from limestone pit rock walls can cause construction hazards. To ensure safe construction and avoid inaccurate grouting, localized detection work is necessary. Borehole-to-surface electrical resistivity tomography (ERT) has high resolution, is sensitive to low resistivity anomalies such as water, can obtain deeper geoelectric information than surface ERT, and is effective in high resolution detection of water-inrush channels. In this study, a total of eight geoelectric models were established for numerical simulation analysis, using single anomaly imaging with pole-pole, pole-dipole, dipole–dipole, and mixed arrays. Complex geological anomalies were imaged under a mixed array. At the Guangxi Pingnan limestone mine water project, this method successfully located and produced images of the water channel behind the water-inrush point of the pit wall. This effectively guided the grouting and blockage of the water channel.

Additional file 1: Table S1. List of antibodies used in this work. Table S2. List of primers used for qRT-PCR analysis. Table S3. Assessment of pain in rabbit model. Fig. S1. Diameter distribution of CB and CB/Lid-n (n = 0, 5, 10). Fig. S2. (a) The thickness of derma and (b) collagen density in plantar inflammation model. Values are expressed as the mean ± SD (n = 3). Compared to control group, *P < 0.05, **P < 0.01, ***P < 0.001. Fig. S3. Results of toluidine blue staining assay, Scale bar: 200 µm. Fig. S4. (a) Dynamic changes of the edema ratio; (d) Dynamic changes of thermal withdrawal latency. Values are expressed as the mean ± SD (n = 3). *P< 0.05, **P< 0.01, ***P< 0.001. Fig. S5. (a) The construction process of VX2-tumor bearing model; (b) VX2-tumor tissues were successfully transplanted into the liver of rabbits. Fig. S6. (a) Optical images of liver tissues immediately after TAE treatment; (b) Quantitative results of Ki67 immunofluorescence staining assay, and the percentage of area positive for fluorescence was manually counted; (c) Quantitative results of TUNEL assay; (d) HE staining images of lung tissue with metastatic tumor lesions. Scale bar: 500 µm. Values are expressed as the mean ± SD (n = 3). **P< 0.01, ***P< 0.001. Fig. S7. (a) Schematic illustration of TAE trestment; (b) Plasma concentration of Lid. Fig. S8. Immunohistochemical images of Nav 1.7 at different magnification. Scale bar: 300 or 60 µm. Fig. S9. Immunohistochemical images of TNF-α at different magnification. Scale bar: 300 or 60 µm. Fig. S10. Immunohistochemical images of IL-6 at different magnification. Scale bar: 300 or 60 µm. Fig. S11. Immunohistochemical images of IL-10 at different magnification. Scale bar: 300 or 60 µm.

Compressed sensing (CS) model of complex-valued data can represent the signal recovery process of a large amount types of radar systems, especially when the measurement matrix is row-orthogonal. Based on debiased least absolute shrinkage and selection operator (LASSO), detection problem under Gaussian random design model, i.e. the elements of measurement matrix are drawn from Gaussian distribution, is studied by literature. However, we find that these approaches are not suitable for row-orthogonal measurement matrices, which are of more practical relevance. In view of statistical mechanics approaches, we provide derivations of more accurate test statistics and thresholds (or p-values) under the row-orthogonal design model, and theoretically analyze the detection performance of the present detector. Such detector can analytically provide the threshold according to given false alarm rate, which is not possible with the conventional CS detector, and the detection performance is proved to be better than that of the traditional LASSO detector. Comparing with other debiased LASSO based detectors, simulation results indicate that the proposed approach can achieve more accurate probability of false alarm when the measurement matrix is row-orthogonal, leading to better detection performance under Neyman-Pearson principle., Comment: 43 pages, 7 figures

Additional file 1: Figure S1. Synthesis of DSPE-PEG2000-CFH. Figure S2. FT-IR spectrums of (A) FT-IR, (B) DSPE-PEG2000-MAL, and (C) DSPE-PEG2000-CFH. Figure S3. 1 H-NMR spectrums of DSPE-PEG2000-MAL and DSPE-PEG2000-CFH. Figure S4. MALID-TOF MS spectrums of DSPE-PEG2000-MAL and DSPE-PEG2000-CFH. Figure S5. Changes in particle size and zeta potential of CFH/OM-L after incubation with (A) mice plasma for 24 h and (B) PBS under the environment of pH 7.4 for 40 days. (C) Release profile of OM, OM-L and CFH/OM-L in PBS of pH 7.4 for 24 h. Data are represented as mean �� SD, n = 3, ***P

Modern radars often adopt multi-carrier waveform which has been widely discussed in the literature. However, with the development of civil communication, more and more spectrum resource has been occupied by communication networks. Thus, avoiding the interference from communication users is an important and challenging task for the application of multi-carrier radar. In this paper, a novel frequency allocation strategy based on the historical experiences is proposed, which is formulated as a Markov decision process (MDP). In a decision step, the multi-carrier radar needs to choose more than one frequencies, leading to a combinatorial action space. To address this challenge, we use a novel iteratively selecting technique which breaks a difficult decision task into several easy tasks. Moreover, an efficient deep reinforcement learning algorithm is adopted to handle the complicated spectrum dynamics. Numerical results show that our proposed method outperforms the existing ones.

This paper studies the problem surrounding distributed passive arrays (sensors) locating multiple emitters while performing self-calibration to correct possible errors in the assumed array directions. In our setting, only the angle-of-arrival (AoA) information is available for localization. However, such information may contain bias due to array directional errors. Hence, localization requires self-calibration. To achieve both, the key element behind our approach is that the received signals from the same emitter should be geometrically consistent if sensor arrays are successfully calibrated. This leads to our signal model, which is built on a mapping directly from emitter locations and array directional errors to received signals. Then we formulate an atomic norm minimization and use group sparsity to promote geometric consistency and align ‘ghost’ emitter locations from calibration errors. Simulations verify the effectiveness of the proposed scheme. We derive the Cramér Rao lower bound and numerically compare it to the simulations. Furthermore, we derive a necessary condition as a rule of thumb to decide the feasibility of joint localization and calibration.

Zhangbei four terminal flexible power grid project has greatly improved the new energy consumption capacity of the region, but the characteristics of electronic power supply on both sides of the new energy transmission line also bring the problem of insufficient sensitivity to the traditional AC protection. In this paper, it is proposed that the sensitivity of new energy transmission line can be improved theoretically by configuring double-K value differential protection for new energy transmission line. Based on the PSCAD software platform, the full electromagnetic transient simulation model of Zhangbei four terminal flexible power grid with large-scale new energy access is built. The sensitivity of differential protection for all new energy transmission lines is checked. According to the simulation results, the setting value of double-K value differential protection is determined. The double-K value differential protection principle proposed in this paper can take into account the new energy transmission line The sensitivity and reliability of the outgoing line are analysed.

The protection device test of flexible DC transmission system is one of the difficult problems in the current protection device test. The field detection conditions of RTDS and other large-scale equipment are limited, and the traditional relay protection tester can not output high-frequency signal, so it is not suitable for the field detection of ultra-high-speed protection of flexible DC transmission line. There is no effective test method for the protection device test of flexible HVDC transmission system. Based on IEC60870-5-1 protocol of interface between test device and Xuji control and protection device, this paper develops a traveling wave ranging and traveling wave protection test device for flexible DC lines, including data preprocessing module and data format transformation module.

As a typical signal processing problem, multidimensional harmonic retrieval (MHR) has been adapted to a wide range of applications in signal processing. Block-sparse signals, whose nonzero entries appearing in clusters, have received much attention recently. An unfolded network, named Ada-BlockLISTA, was proposed to recover a block-sparse signal at a small computational cost, which learns an individual weight matrix for each block. However, as the number of network parameters is increasingly associated with the number of blocks, the demand for parameter reduction becomes very significant, especially for large-scale MHR. Based on the dictionary characteristics in two-dimensional (2D) harmonic retrieve problems, we introduce a weight coupling structure to shrink Ada-BlockLISTA, which significantly reduces the number of weights without performance degradation. In simulations, our proposed block-sparse reconstruction network, named AdaBLISTA-CP, shows excellent recovery performance and convergence speed in 2D harmonic retrieval problems., Comment: 2 pages, 2 figures, 13 conferences

In this paper, we consider the recovery of the high-dimensional block-sparse signal from a compressed set of measurements, where the non-zero coefficients of the recovered signal occur in a small number of blocks. Adopting the idea of deep unfolding, we explore the block-sparse structure and put forward a block-sparse reconstruction network named Ada-BlockLISTA, which performs gradient descent on every single block followed by a block-wise shrinkage. Furthermore, we prove the linear convergence rate of our proposed network, which also theoretically guarantees exact recovery for a potentially higher sparsity level based on underlyingblock structure. Numerical results indicate that Ada-BlockLISTA yields better signal recovery performance compared with existing algorithms, which ignore the additional block structure in the signal model., Comment: 12 pages, 7 figures, 35 conferences

When urban subway lines pass under buildings, it is often necessary to carry out corresponding pile foundation detection work to ensure construction safety. However, detecting the distribut...

Background Sun’s procedure is currently recognized as the standard procedure for acute type A aortic dissection (AAAD). But the operation istoo difficult for beginners. We hope to reduce the difficulty and complications of this operation. Methods The aortic arch was immediately cross-clamped after the stented graft was inserted into the distal aorta. Thereafter, the lower-body perfusion was restored. Then, anastomosis was performed between the proximal stent graft and the distal 4-branched Dacron graft. The other arteries were anastomosed to the arched branch of the 4-branched graft. Results The cardiopulmonary bypass (CPB) time was (207 ± 52) min, and the aortic cross-clamp time was (114 ± 39) min. The circulatory arrest time was (38 ± 16) sec. One patient (4%) died. The incidence of complications was stroke (4%), renal dysfunction requiring dialysis (4%), prolonged intubation(12%). Conclusions The time of circulatory arrest in this operation is less than 1 min, which can avoid the complications caused by DHCA and decrease risk of bleeding and complexity by shifting anastomosis more proximally. The effect of our operation is similar to and even better than that of Sun’s procedure. It does not even require relatively advanced skill, much experience and excellent psychological quality, especially suitable for beginners.

With the development of flexible DC transmission and the shortage of transmission corridors, flexible DC transmission lines may be erected on the same tower or span vertically with traditional AC lines, greatly increasing the possibility of cross-line fault between flexible DC lines and AC lines. This paper focuses on this issue. Based on the equivalent circuit, the short-circuit current at the initial stage of this cross-line fault is analyzed first. Then, based typical ±500kV flexible DC system and Extremely High Voltage (EHV) AC system in China, the simulation model is established in Power Systems Computer Aided Design (PSCAD). The fault transient characteristics of cross-line fault is analyzed, and the significant interaction effect of AC and DC systems is verified. On this basis, the response of DC traveling wave protection to this cross-line fault is tested. Simulation results show that the values and gradients of fault traveling wave decrease under cross-line fault, and the reliability of traveling wave protection decreases.

In order to realize shadow automatic generation in 2D animation production, an automatic shadow generation algorithm based on gray histogram feature segmentation and edge contour feature extraction is proposed, and the image processing model of 2D animation is constructed. The edge contour feature of 2D animation image is extracted, and the gray pixel value fusion and difference feature extraction are carried out in the process of shadow automatic generation by using depth learning algorithm. The shaded area of 2D animation image is calibrated by the regional grid segmentation, and the multi-scale Retinex color feature component of 2D animation image is extracted by using Radon scale transform, and the gray histogram of shadow region of 2D animation image is constructed. The simulation results show that the shadow can be generated automatically by using the algorithm, the shadow expression ability of the image and the quality of the output image are better. The normalized correlation coefficient of shadow region is high, which shows that shadow generation is effective.

The fault analysis of AC outlets in VSC HVDC power grid is the basis of AC protection configuration. This paper analyzes the influence of negative sequence suppression strategy on negative sequence current and positive and negative sequence voltage of converter station, studies the influence of outer loop limiting controller on short-circuit current, analyzes the mechanism of low-voltage limiting strategy on positive sequence current, and obtained the impedance angle of AC outlets fault in VSC HVDC power grid, The simulation results show that the control strategy has an effect on the amplitude and phase angle of the short-circuit current. This study provides a basis for the analysis of the influence of the VSC HVDC power grid on the AC protection.

Objective: Aortic arch replacement in acute type A aortic dissection patients remains a most challenging cardiovascular operation. This article aims to show our Modified Y-Graft Technique using the Femoral Artery Bypass (FAB) and the One Minute Systemic Circulatory Arrest (OSCA) Technique and assess the short-term outcomes of the patients. Methods: Between February 2015 and November 2017, 51 patients with acute type A aortic dissection underwent aortic arch replacement. Among them, 23 patients' procedure used FAB and 28 patients utilized both FAB and OSCA. The intraoperative data and postoperative follow-up data were recorded. The follow-up data of patients with traditional Y-graft technique were collected from previous reported studies. Results: In FAB group, two patients died for pulmonary infection (30-day survival rate 91.3%), and two patients paralyzed from the waist down. The hemodialysis was performed for five patients (21.7%) before hospital discharge. Fifteen patients (65.2%) received more than 2-day's respiratory support and 8 patients (34.8%) received more than 5-day's respiratory support. These follow-up data are basically flat or precede to the patients with traditional Y-graft technique. Furthermore, compared to the FAB Group, the morbidity of the neurologic dysfunction and the acute renal failure was significantly reduced in FAB+OSCA Group. Besides, the respiratory support, the length of the postoperative stay and the ICU stay were shortened. Conclusions: This study clarified the feasibility of FAB and OSCA technique in modifying Y-graft technique. The acute type A aortic dissection patients tend to have less surgical complications and favorable short-term outcomes by this surgery. Funding Statement: The study has no funding. Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: All procedures performed in studies involving human participants were approved by the Ethics Committee of Qilu Hospital of Shandong University.

For measuring internal stresses in rock and soil masses, specifically on unstable slopes, the fiber Bragg grating (FBG) and optical time-domain reflectometer (OTDR) methods based on fiber sensing technology have disadvantages such as low spatial resolution, low measurement accuracy, and non-distributed measurements. This paper presents a quasi-distributed thrust measurement system based on an optical frequency domain reflectometer (OFDR). First, the optical fiber stress sensing head was designed based on the micro-bending effect of the optical fiber, the cubic spline interpolation method was then used to compensate for the nonlinear effects of the OFDR stress sensing system, the compensation effects of different software methods were compared and analyzed simultaneously, which significantly improved the resolution and spatial-positioning capabilities of the OFDR sensing system, and error calibration was then performed through laboratory experiments of lateral stress. The test results showed that the OFDR sensing system achieved a spatial resolution of 20 cm using a 500 m test fiber (the resolution of an OTDR sensing system is generally approximately 1 m), the maximum measurement pressure can reach 1.059 MPa and the maximum relative error is 8.9 %. Finally, the field engineering application was carried out in the Chenjiagou landslide in Fengjie County, Chongqing City, Three Gorges Dam, China. The application results showed that the system can accurately locate six fiber optic micro-bending stress sensors installed within the landslide body over a range of 0 ~ 420 m and can obtain the pressure values of their lateral thrusts. This system is a quasi-distributed stress monitoring instrument that provides long measurement distances, high spatial resolutions, high sensitivities, and fast responses that can be used for unstable slopes, slope engineering, water conservation and hydropower dams, and tunnel chambers, and thus, has good engineering application prospects in the safety monitoring field.

Automotive radar is a key component in an ADAS. The increasing number of radars implemented in vehicles makes interference between them a noteworthy issue. One method of interference mitigation is to limit the TBP of radar waveforms. However, the problems of how much TBP is necessary and how to optimally utilize the limited TBP have not been addressed. We take CWS as an example and propose a method of designing the radar waveform parameters oriented by the performance of CWS We propose a metric to quantify the CWS performance and study how the radar waveform parameters (bandwidth and duration) influence this metric. Then, the waveform parameters are designed with a limit on the TBP to optimize the system performance. Numerical results show that the proposed design outperforms the state-of-the-art parameter settings in terms of system performance and resource or energy efficiency., Comment: 13 pages, 6 figures. Submitted to IEEE Transactions on Signal Processing

During tunnel construction, large groundwater influx poses serious safety hazards. To ensure construction safety, effective measures such as early warning, grouting, and framework support are needed to counteract potential water hazards. It is also critical to clarify the spatial location and size of the water-bearing geological structures before construction to avoid catastrophe. Electrical resistivity tomography (ERT) operates at a high resolution and is sensitive to low-resistivity targets such as water. Thus, it has strong application potential for the detection of karst geomorphology around tunnel construction. However, the use of a single-ERT method may not be sufficient to accurately locate the spatial distribution of karst features. Therefore, it is necessary to carry out multiple-ERT data fusion to generate a comprehensive interpretation of karst geohazards. According to the spatial distribution of different karst caves, we established four geoelectric models for numerical simulation based on the method of principal component analysis. Studies have shown that data fusion is superior to conventional comparative analysis of geophysical data results and creates a more accurate comprehensive description of the same target. For example, inversion data fusion improves poor imaging of the cross-hole ERT near the borehole and reduces the distribution of pseudo-anomalies near the electrode. In this study, the vertical resolution of the surface ERT, and the horizontal resolution of the cross-hole ERT were both improved, while the imaging ability of the borehole-surface ERT in the peripheral low-sensitivity area was enhanced. Moreover, a three-dimensional (3D) conversion method of two-dimensional (2D) detection data in the tunnel environment was employed. An interpolation 3D-imaging of the 2D detection data was carried out, rendering the interpretation of the results more intuitive and comprehensive. Finally, we applied this method in the Daba Tunnel Water Governance Project in Hunan Province, China, and demonstrated that it could overcome the limitations of the single-ERT survey. We were able to accurately delineate the distribution range of the main water-rich bodies around the tunnel. Our findings provide key guidance for the successful implementation of tunnel water-inrush treatment.

A translational landslide comprising nearly horizontal sand and mud interbed was widely developed in the Ba river basin of the Qinba–Longnan mountain area. Scholars have conducted theoretical research on this rainfall-induced landslide; however, owing to the lack of landslide monitoring engineering and data, demonstrating and validating the theoretical research wasdifficult. This study considered a translational landslide with an unusual morphology: the Wobaoshi landslide, which is located in Bazhong city, China. First, the formation conditions of this landslide were ascertained through field exploration, and the deformation and failure characteristics of the plate-shaped sliding body were analyzed. Then, long-period monitoring engineering was conducted to obtain multi-parameter monitoring data, such as crack width, rainfall intensity, and pore-water pressure. Finally, through the mechanical model analysis of the multi-stage sliding bodies, the calculating formula of the maximum height of the multi-stage plate girders, hcr, was derived，and the long-period monitoring data were used to verify its accuracy. Combined with numerical simulation and calculations, the deformation and failure modes of the plate-shaped sliding bodies were analyzed and explored. In this paper, the multi-parameter monitoring data proved that the stability of the sliding body is affected greatly by the rainfall intensity and pore-water pressure and the pore-water pressure in the crack is positive for the beginning of the plate-shaped sliding bodies, and an optimization monitoring method for this type of landslide was proposed. Therefore, this paper has theoretical and practical significance for the intensive study of translational landslides in this area.

The concept of cognitive radar (CR) enables radar systems to achieve intelligent adaption to a changeable environment with feedback facility from receiver to transmitter. However, the implementation of CR in a fast-changing environment usually requires a well-known environmental model. In our work, we stress the learning ability of CR in an unknown environment using a combination of CR and reinforcement learning (RL), called RL-CR. Less or no model of the environment is required. We also apply the general RL-CR to a specific problem of automotive radar spectrum allocation to mitigate mutual interference. Using RL-CR, each vehicle can autonomously choose a frequency subband according to its own observation of the environment. Since radar's single observation is quite limited compared to the overall information of the environment, a long short-term memory (LSTM) network is utilized so that radar can decide the next transmitted subband by aggregating its observations over time. Compared with centralized spectrum allocation approaches, our approach has the advantage of reducing communication between vehicles and the control center. It also outperforms some other distributive frequency subband selecting policies in reducing interference under certain circumstances., This article is an old version of the newly submitted article with identifier 2001.02629

The Third Pole (TP) is experiencing rapid warming and is currently in its warmest period in the past 2,000 years. This paper reviews the latest development in multidisciplinary TP research associated with this warming. The rapid warming facilitates intense and broad glacier melt over most of the TP, although some glaciers in the northwest are advancing. By heating the atmosphere and reducing snow/ice albedo, aerosols also contribute to the glaciers melting. Glacier melt is accompanied by lake expansion and intensification of the water cycle over the TP. Precipitation has increased over the eastern and northwestern TP. Meanwhile, the TP is greening and most regions are experiencing advancing phenological trends, although over the southwest there is a spring phenological delay mainly in response to the recent decline in spring precipitation. Atmospheric and terrestrial thermal and dynamical processes over the TP affect the Asian monsoon at different scales. Recent evidence indicates substantial roles that mesoscale convective systems play in the TP’s precipitation as well as an association between soil moisture anomalies in the TP and the Indian monsoon. Moreover, an increase in geohazard events has been associated with recent environmental changes, some of which have had catastrophic consequences caused by glacial lake outbursts and landslides. Active debris flows are growing in both frequency of occurrences and spatial scale. Meanwhile, new types of disasters, such as the twin ice avalanches in Ali in 2016, are now appearing in the region. Adaptation and mitigation measures should be taken to help societies’ preparation for future environmental challenges. Some key issues for future TP studies are also discussed.

A new deep-learning-based reduced-order modeling (ROM) framework is proposed for application in subsurface flow simulation. The reduced-order model is based on an existing embed-to-control (E2C) framework and includes an auto-encoder, which projects the system to a low-dimensional subspace, and a linear transition model, which approximates the evolution of the system states in low dimension. In addition to the loss function for data mismatch considered in the original E2C framework, we introduce a physics-based loss function that penalizes predictions that are inconsistent with the governing flow equations. The loss function is also modified to emphasize accuracy in key well quantities of interest (e.g., fluid production rates). The E2C ROM is shown to be very analogous to an existing ROM, POD-TPWL, which has been extensively developed for subsurface flow simulation. The new ROM is applied to oil-water flow in a heterogeneous reservoir, with flow driven by nine wells operating under time-varying control specifications. A total of 300 high-fidelity training simulations are performed in the offline stage, and the network training requires 10-12~minutes on a Tesla V100 GPU node. Online (runtime) computations achieve speedups of $\mathcal{O}$(1000) relative to full-order simulations. Extensive test case results, with well controls varied over large ranges, are presented. Accurate ROM predictions are achieved for global saturation and pressure fields at particular times, and for injection and production well responses as a function of time. Error is shown to increase when 100 or 200 (rather than 300) training runs are used to construct the E2C ROM., Comment: Submitted for review in Journal of Computational Physics

Randomized Stepped Frequency Radar (RSFR) is very attractive for tasks under complex electromagnetic environment. Due to the synthetic high range resolution in RSRFs, a target usually occupies a series of range cells and is called an extended target. To reconstruct the range-Doppler information in a RSFR, previous studies based on sparse recovery mainly exploit the sparsity of the target scene but do not adequately address the extended-target characteristics, which exist in many practical applications. Block sparsity, which combines the sparsity and the target extension, better characterizes a priori knowledge of the target scene in a wideband RSFR. This paper studies the RSFR range-Doppler reconstruction problem using block sparse recovery. Particularly, we theoretically analyze the block coherence and spectral norm of the observation matrix in RSFR and build a bound on the parameters of the radar, under which the exact recovery of the range-Doppler information is guaranteed. Both simulation and field experiment results demonstrate the superiority of the block sparse recovery over conventional sparse recovery in RSFRs., Comment: 12 pages, 8 figures

Self-driving cars constantly asses their environment in order to choose routes, comply with traffic regulations, and avoid hazards. To that aim, such vehicles are equipped with wireless communications transceivers as well as multiple sensors, including automotive radars. The fact that autonomous vehicles implement both radar and communications motivates designing these functionalities in a joint manner. Such dual function radar-communications (DFRC) designs are the focus of a large body of recent works. These approaches can lead to substantial gains in size, cost, power consumption, robustness, and performance, especially when both radar and communications operate in the same range, which is the case in vehicular applications. This article surveys the broad range of DFRC strategies and their relevance to autonomous vehicles. We identify the unique characteristics of automotive radar technologies and their combination with wireless communications requirements of self-driving cars. Then, we map the existing DFRC methods along with their pros and cons in the context of autonomous vehicles, and discuss the main challenges and possible research directions for realizing their full potential., Comment: 21 pages

This paper aims at revealing the hydraulic fracturing effect of hydrodynamic influencing factors of fracturing fluid by laboratory experiments. The experimental design for huge number of hydrodynamic influencing factors with many levels, is oftentimes incorporated with the conventional methods, i.e. Based on the PKN model, injection rate, viscosity, and density (of the fracturing fluid) and their parameter values (levels) were considered for the construction of an optimal mixed-level design table U* 12(43×6), which constructed the optimization scheme. The experiments results were subjected to multiple regression analysis to establish optimal fitting formulas for the relationship of single factor or multi-factor with rock fracturing value. Compared with other experimental designs, experimental number of U* 12(43×6) yielded only half the number of experiments in the orthogonal design L24(43×6) and presented better distribution uniformity of experimental points than Ui2(43×6). This paper provides a fast and effective experimental scheme for the effect analysis, as well as a substantially accurate method for in-situ stress measurement.

A modified sol–gel (MSG) method was developed to synthesize perovskite La1−x Sr x MnO3 (x = 0.2, 0.4, 0.6, 0.8) with large specific surface area that allows for control of their particle size from the micrometer level to the nanometer level with novel nanoporous structure. The MSG method utilized carbon black (Vulcan XC-72R) as a pore-forming material during the preparation process. Two important process parameters, the calcination temperature and the pore former material addition, were investigated to control the size of the La1−x Sr x MnO3 particles. The phase evolution of La1−x Sr x MnO3 powders was investigated by thermogravimetric analysis (TG/DSC) and X-ray diffraction pattern. The results showed that the pure La0.6Sr0.4MnO3 phase has been obtained at about 550 °C in air, which is lowered around 150 °C comparing to conventional sol–gel method. In scanning electron microscope studied, it presented novel homogeneous nanoporous morphology with the average particle size from 30 to 100 nm. Based on the Brunauer–Emmett–Teller method analysis, the specific surface area of La1−x Sr x MnO3 was significantly influenced by the calcination temperature, the pore former material addition and the strontium content. The largest specific surface area of La0.2Sr0.8MnO3 reached 114.3 m2/g.

This article provides a comprehensive review of the global monsoon that encompasses findings from studies of both modern monsoons and paleomonsoons. We introduce a definition for the global monsoon that incorporates its three-dimensional distribution and ultimate causes, emphasizing the direct drive of seasonal pressure system changes on monsoon circulation and depicting the intensity in terms of both circulation and precipitation. We explore the global monsoon climate changes across a wide range of timescales from tectonic to intraseasonal. Common features of the global monsoon are global homogeneity, regional diversity, seasonality, quasi-periodicity, irregularity, instability, and asynchroneity. We emphasize the importance of solar insolation, Earth orbital parameters, underlying surface properties, and land-air-sea interactions for global monsoon dynamics. We discuss the primary driving force of monsoon variability on each timescale and the relationships among dynamics on multiple timescales. Natural processes and anthropogenic impacts are of great significance to the understanding of future global monsoon behavior.

In this paper, fiber grating technology is used for accurately measure stresses, temperature and displacement. The paper introduces the basic principles of FBG technology and the wavelength demodulation method of FBG sensors, and put fiber grating technology into practical engineering projects. The paper design a optical fiber grating real-time automation monitoring system to distributed measure stress, temperature and displacement in geological disaster body, to provide effective technical supports for geological disaster prevention and mitigation.

This paper describes the model speed and model In/Out (I/O) efficiency of the high-resolution atmospheric general circulation model FAMIL (Finite-volume Atmospheric Model of IAP/LASG) at the National Supercomputer Center in Tianjin, China, on its Tianhe-1A supercomputer platform. A series of three-model-day simulations were carried out with standard Aqua Planet Experiment (APE) designed within FAMIL to obtain the time stamp for the calculation of model speed, simulation cost, and model I/O efficiency. The results of the simulation demonstrate that FAMIL has remarkable scalability below 3456 and 6144 cores, and the lowest simulation costs are 1536 and 3456 cores for 12.5 km and 6.25 km resolutions, respectively. Furthermore, FAMIL has excellent I/O scalability and an efficiency of more than 80% on 6 I/Os and more than 99% on 1536 I/Os.

The organization of rainy day traffic flow will appear a certain confusion especially in moderate rain or more rainfall, causing a large number of bus passengers gathered at bus stops. By means of the data acquisition and analysis of the site passenger cell phone signal, we can match the sites where having more passengers with bus lines. The bus dispatching department can conduct temporary scheduling to reduce crowding bus stops. This article firstly introduces the main characteristic of mobile technology and mobile phone signal data, and puts forward the phone signaling data of the passengers on bus stations in rainy day, providing the reference suggestion for the bus temporary scheduling. Finally, we analyze the feasibility of bus dispatching using mobile phone signaling data on rainy days.

Combining testing data, analyses some main problems existed in the application of ground-source heat pump (GSHP) technique through testing and assessing on thermal performance of typical GSHP system in winter conditions. Presents some corresponding measures, provides basic conditions for the future promotion of GSHP technology.