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Abstract Background The incidence and mortality of pancreatic cancer (PC) has gradually increased. The aim of this study was to identify survival-related DNA methylation (DNAm)-driven genes and establish a nomogram to predict outcomes in patients with PC. Methods The gene expression, DNA methylation database, and PC clinical samples were downloaded from TCGA. DNAm-driven genes were identified by integrating analyses of gene expression and DNA methylation data. Survival-related DNAm-driven genes were screened via univariate, least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression analyses to develop a risk score model for prognosis. Based on analyses of clinical parameters and risk score, a nomogram was built and validated. The independent cohort from GEO database were used for external validation. Results A total of 16 differentially expressed methylation-driven genes were identified. Based on LASSO Cox regression and multivariate Cox regression analysis, six genes (FERMT1, LIPH, LAMA3, PPP1R14D, NQO1, VSIG2) were chosen to develop the risk score model. In the Kaplan–Meier analysis, age, T stage, N stage, AJCC stage, radiation therapy history, tumor size, surgery type performed, pathological type, chemotherapy history, and risk score were potential prognostic factors in PC (P < 0.1). In the multivariate analysis, stage, chemotherapy, and risk score were significantly correlated to overall survival (P < 0.05). The nomogram was constructed with the three variables (stage, chemotherapy, and risk score) for predicting the 1-year, 2-year, and 3-year survival rates of PC patients. Nomogram performance was assessed by receiver operating characteristic (ROC) curves and calibration curves. 1-year, 2-year and 3-year AUC of nomogram model was 0.899, 0.765 and 0.776, respectively. Conclusions In our study, we successfully identified the six DNAm-driven genes (FERMT1, LIPH, LAMA3, PPP1R14D, NQO1, VSIG2) with a relationship to the outcomes of PC patients. The nomogram including stage, chemotherapy, and risk score could be used to predict survival in PC patients.

Explosive welding is a useful method for joining similar or dissimilar metal alloys that are not easily joined by any other means of welding. Insertion of an interlayer between two-parent plates is beneficial to control the welding parameters and improve the welding quality. In order to investigate the importance of interlayer during the explosive welding process, this paper presents the numerical simulation of explosive welding of Ti6Al4V-SS304 in the presence of different interlayer materials, i.e. SS304, Ti6Al4V, CP-Ti, Cu, Al. To understand the whole welding process with efficient computational time, coupled smoothed particle hydrodynamics -Euler -Arbitrary Lagrangian-Eulerian formulation was opted. Results were analyzed on the basis of different material interlayers. Welding parameters, i.e. pressure, temperature, plastic strain and interface morphology revealed that interlayer improved the welding quality. Furthermore, as an interlayer, the materials with high strength showed high welding strength.

In order to investigate the mechanism of explosive welding and the influences of explosive welding parameters on the welding quality, this paper presents numerical simulation of the explosive welding of Al-Mg plates using Smoothed Particle Hydrodynamics method. The multi-physical phenomena of explosive welding, including acceleration of the flyer plate driven by explosive detonation, oblique collision of the flyer and base plates, jetting phenomenon and the formation of wavy interface can be reproduced in the simulation. The characteristics of explosive welding are analyzed based on the simulation results. The mechanism of wavy interface formation is mainly due to oscillation of the collision point on the bonding surfaces. In addition, the impact velocity and collision angle increase with the increase of the welding parameters, such as explosive thickness and standoff distance, resulting in enlargement of the interfacial waves.

Coupled ice sheet–ocean models are increasingly being developed and applied to important questions pertaining to processes at the Greenland and Antarctic Ice Sheet margins, which play a pivotal role in ice sheet stability and sea level rise projections. One of the challenges of such coupled modelling activities is the timescale discrepancy between ice and ocean dynamics. This discrepancy, combined with the high computational cost of ocean models due to their finer temporal resolution, limits the time frame that can be modelled. In this study, we introduce an “accelerated forcing” approach to address the timescale discrepancy and thus improve computational efficiency in a framework designed to couple evolving ice geometry to ice shelf cavity circulation. This approach is based on the assumption that the ocean adjusts faster to imposed changes than the ice sheet, so the ocean can be viewed as being in a quasi-steady state that varies slowly over timescales of ice geometry change. By assuming that the mean basal melt rate during one coupling interval can be reflected by a quasi-steady-state melt rate during a shortened coupling interval (equal to the regular coupling interval divided by a constant factor), we can reduce the ocean model simulation duration. We first demonstrate that the mean cavity residence time, derived from standalone ocean simulations, can guide the selection of suitable scenarios for this approach. We then evaluate the accelerated forcing approach by comparing basal melting response under the accelerated forcing with that under the regular forcing (without the accelerated forcing) based on idealized coupled ice sheet–ocean model experiments. Our results suggest that the accelerated approach can yield comparable melting responses to those under the regular forcing approach when the model is subjected to steady far-field ocean conditions or time-varying conditions with timescales much shorter than the cavity residence time. However, it may not be suitable when the timescale of the accelerated ocean conditions is not significantly different from the cavity residence time. We have also discussed the limitations of applying the accelerated forcing approach to real-world scenarios, as it may not be applicable in coupled modelling studies addressing climate variability on sub-decadal, decadal, and mixed timescales or in fully coupled climate models with interactive ice sheets. Nevertheless, when appropriately applied, the accelerated approach can be a useful tool in process-oriented coupled ice sheet–ocean modelling or for downscaling climate simulations with a coupled ice sheet–ocean model.

Background: The development of learning attitudes during middle school transition and adaptation is critical, as shown by Self-Determination Theory (SDT). However, the development of adolescents' learning attitudes throughout middle school and the impact of parenting styles on this development remains largely unexplored. Objective: This research aimed to examine the development of adolescents' learning attitudes in South Korean middle school students, and the role of parenting styles in shaping these attitudes, applying the Self-Determination Theory framework and using longitudinal data. Method: Data was sourced from the Korea Children and Youth Panel Survey 2018 (KCYPS 2018), involving a national sample of 2,590 7th grade students. A Latent Transition Analysis (LTA) was employed to determine developmental trajectories and assess the impact of parenting styles on latent profile memberships, taking into account other covariates. Results: The analysis revealed three latent learning attitude profiles: Helpless, General, and Engaged. It showed a general tendency for learning attitude profiles to regress towards the General profile over time, but also a likelihood of consolidation. Significantly, autonomy-supportive and coercive parenting styles had a substantial influence on profile membership probabilities, though their effects varied in nuances. Conclusions: The findings indicate that while the autonomy-supportive parenting style fosters General or Engaged profiles among middle school students, curbing coercive parenting styles is necessary for developing the Engaged profile. In light of the timing and learning attitude profile, personalized and specific interventions in family and educational contexts are recommended.

ABSTRACT Guillain‐Barré syndrome (GBS) is characterized classically by progressive and symmetrical motor weakness and areflexia. We describe a case of GBS with initially preserved reflexes and power, leading to delayed diagnosis, who latterly required urgent ventilator support and plasmapharesis to highlight the importance of considering atypical presentations of this common condition.

Background: Increasing evidence suggests an association between ele­vated serum aminotransferase levels and metabolic disorders (metabolic syndrome, hyperlipemia and diabetes mellitus). However, the significance of relatively low levels of aminotransferases in relation to metabolic disorders has not been fully investigated in the general population. We inves­tigated the association between serum amiontransferase levels and metabolic disorders using data from a survey in Jilin province, China.Methods: In 2007, a survey was conducted throughout Jilin, China, covering both urban and rural areas. A total of 3835 people, 18 to 79 years old including 1761 men and 2074 women, underwent real-time ultrasonography, blood tests including aspartate aminotransferase and alanine aminotransferase, and had interviews with a structured questionnaire.Results: Serum aminotransferase levels within the normal range were asso­ciated with metabolic syndrome independent of age, occupation, cultural and educational level, income, body mass index, waist circumference, smoking, and alcohol intake. Compared with the lowest level (50 IU/L were 1.92, 2.50, 2.97, and 3.52 in men, and 1.38 , 1.54, 3.06, and 2.62 in women, respectively. Near-normal serum aminotransferase levels asso­ciated with hyperlipemia, NAFLD, DM were also found in the study.Conclusions: Normal to near-normal serum aminotransferase levels are associated with metabolic disorders. Serum ALT levels of 21-25 IU/L for men, and 17-22 IU/L for women are suggested as cutoff levels that detect metabolic disorders affecting the liver.

Induced pluripotent stem cells (iPSCs) have the potential to revolutionise cell therapy; however, it remains unclear whether iPSCs can be generated from human osteoarthritic chondrocytes (OCs) and subsequently induced to differentiate into chondrocytes. In the present study, we investigated the differentiation potential of OCs into iPSCs using defined transcription factors and explored the possibility of using these OC-derived iPSCs for chondrogenesis. Our study demonstrates that iPSCs can be generated from OCs and that these iPSCs are indistinguishable from human embryonic stem cells (hESCs). To promote chondrogenic differentiation, we used lentivirus to transduce iPSCs seeded in alginate matrix with transforming growth factor-β1 (TGF-β1) and then in vitro co-cultured these iPSCs with chondrocytes. Gene expression analysis showed that this combinational strategy promotes the differentiation of the established iPSCs into chondrocytes in alginate matrix. Increased expression of cartilage-related genes, including collagen II, aggrecan, and cartilage oligomeric matrix protein (COMP), and decreased gene expression of the degenerative cartilage marker, vascular endothelial growth factor (VEGF), were observed. The histological results revealed a dense sulphated extracellular matrix in the co-culture of TGF-β1-transfected iPSCs with chondrocytes in alginate matrix. Additionally, in vivo chondroinductive activity was also evaluated. Histological examination revealed that more new cartilage was formed in the co-culture of TGF-β1-transfected iPSCs with chondrocytes in alginate matrix. Taken together, our data indicate that iPSCs can be generated from OCs by defined factors and the combinational strategy results in significantly improved chondrogenesis of OC-derived iPSCs. This work adds to our understanding of potential solutions to osteoarthritic cell replacement problem.

Background: Increasing evidence suggests an association between ele­vated serum aminotransferase levels and metabolic disorders (metabolic syndrome, hyperlipemia and diabetes mellitus). However, the significance of relatively low levels of aminotransferases in relation to metabolic disorders has not been fully investigated in the general population. We inves­tigated the association between serum amiontransferase levels and metabolic disorders using data from a survey in Jilin province, China. Methods: In 2007, a survey was conducted throughout Jilin, China, covering both urban and rural areas. A total of 3835 people, 18 to 79 years old including 1761 men and 2074 women, underwent real-time ultrasonography, blood tests including aspartate aminotransferase and alanine aminotransferase, and had interviews with a structured questionnaire. Results: Serum aminotransferase levels within the normal range were asso­ciated with metabolic syndrome independent of age, occupation, cultural and educational level, income, body mass index, waist circumference, smoking, and alcohol intake. Compared with the lowest level (50 IU/L were 1.92, 2.50, 2.97, and 3.52 in men, and 1.38 , 1.54, 3.06, and 2.62 in women, respectively. Near-normal serum aminotransferase levels asso­ciated with hyperlipemia, NAFLD, DM were also found in the study. Conclusions: Normal to near-normal serum aminotransferase levels are associated with metabolic disorders. Serum ALT levels of 21-25 IU/L for men, and 17-22 IU/L for women are suggested as cutoff levels that detect metabolic disorders affecting the liver.

Aiming at the application requirements of underwater cross-domain communication, based on the equivalent relationship between the rotating permanent magnet and the orthogonal time-varying current loop, this paper establishes an air-seawater-seabed three-layer medium model and analyzes the magnetic field distribution and propagation characteristics of the rotating permanent magnet-based mechanical antenna (RMBMA). Based on the electromagnetic field simulation software FEKO, the influence of vertical rotation and horizontal rotation of RMBMA on the radiation magnetic field is analyzed. The magnetic field distribution and magnetic field attenuation characteristics of RMBMA at different depths are obtained by simulation. The influence of RMBMA operating frequency and magnetic moment on the propagation characteristics is studied. The research shows that the horizontal rotation of the magnetic source is better than the vertical rotation in the long-distance underwater communication. When the magnetic source and the receiving point are close to the interface of the medium, the magnetic field strength and the propagation distance can be relatively increased. With appropriate frequency and magnetic moment, the magnetic field strength and communication distance can be further increased.

Through a detailed timing analysis of Fermi-LAT data, the rotational behavior of the γ -ray pulsar PSR J1522−5735 was tracked from 2008 August (MJD 54692) to 2024 January (MJD 60320). During this 15.4 yr period, two overrecovery glitches and four antiglitches were identified, marking a rare occurrence in rotation-powered pulsars (RPPs). The magnitudes of these (net) spin-down glitches were determined to be ∣Δ ν _g / ν ∣ ∼ 10 ^−8 , well above the estimated detectability limit. For the two overrecovery glitches, the respective recovery fractions Q are 2.1(7) and 1.4(2). Further analysis showed no substantial variations in either the flux or pulse profile shape in any of these events, suggesting that small (net) spin-down glitches, unlike large events observed in magnetars and magnetar-like RPPs, may occur without leaving an impact on the magnetosphere. Within the framework of the vortex creep and vortex bending models, antiglitches and overrecoveries indicate the recoupling of vortex lines that moved inward as a result of a crustquake; meanwhile, the apparent fluctuations in the spin-down rate after the glitches occur as a result of the coupling of the oscillations of bent vortex lines to the magnetosphere.

The increasing availability of high-quality remote sensing data and advanced technologies has spurred land cover mapping to characterize land change from local to global scales. However, most land change datasets either span multiple decades at a local scale or cover limited time over a larger geographic extent. Here, we present a new land cover and land surface change dataset created by the Land Change Monitoring, Assessment, and Projection (LCMAP) program over the conterminous United States (CONUS). The LCMAP land cover change dataset consists of annual land cover and land cover change products over the period 1985–2017 at a 30 m resolution using Landsat and other ancillary data via the Continuous Change Detection and Classification (CCDC) algorithm. In this paper, we describe our novel approach to implement the CCDC algorithm to produce the LCMAP product suite composed of five land cover products and five products related to land surface change. The LCMAP land cover products were validated using a collection of ∼25 000 reference samples collected independently across CONUS. The overall agreement for all years of the LCMAP primary land cover product reached 82.5 %. The LCMAP products are produced through the LCMAP Information Warehouse and Data Store (IW+DS) and shared Mesos cluster systems that can process, store, and deliver all datasets for public access. To our knowledge, this is the first set of published 30 m annual land change datasets that include land cover, land cover change, and spectral change spanning from the 1980s to the present for the United States. The LCMAP product suite provides useful information for land resource management and facilitates studies to improve the understanding of terrestrial ecosystems and the complex dynamics of the Earth system. The LCMAP system could be implemented to produce global land change products in the future. The LCMAP products introduced in this paper are freely available at https://doi.org/10.5066/P9W1TO6E (LCMAP, 2021).

Abstract By analyzing 4.48 × 108 ψ(3686) events collected with the BESIII detector, we observe the decays χ cJ → nK S 0 Λ ¯ $$ {nK}_S^0\overline{\Lambda} $$ + c.c. (J = 0, 1, 2) for the first time, via the radiative transition ψ(3686) → γχ cJ . The branching fractions are determined to be (6.65 ± 0.26stat ± 0.41syst) × 10 −4, (1.66 ± 0.12stat ± 0.12syst) × 10 −4, and (3.58 ± 0.16stat ± 0.23syst) × 10 −4 for J = 0, 1, and 2, respectively.

Abstract Using a total of 5.25 fb −1 of e + e − collision data with center-of-mass energies from 4.236 to 4.600 GeV, we report the first observation of the process e + e − → ηψ(2S) with a statistical significance of 4.9 standard deviations. The data sets were collected by the BESIII detector operating at the BEPCII storage ring. We measure the yield of events integrated over center-of-mass energies and also present the energy dependence of the measured cross section.

Abstract The compositional design of metallic glasses (MGs) is a long-standing issue in materials science and engineering. However, traditional experimental approaches based on empirical rules are time consuming with a low efficiency. In this work, we successfully developed a hybrid machine learning (ML) model to address this fundamental issue based on a database containing ~5000 different compositions of metallic glasses (either bulk or ribbon) reported since 1960s. Unlike the prior works relying on empirical parameters for featurization of data, we designed modeling guided data descriptors in line with the recent theoretical models on amorphization in chemically complex alloys for the development of the hybrid classification-regression ML algorithms. Our hybrid ML modeling was validated both numerically and experimentally. Most importantly, it enabled the discovery of MGs (either bulk or ribbon) through the ML-aided deep search of a multitude of quaternary to scenery alloy compositions. The computational framework herein established is expected to accelerate the design of MG compositions and expand their applications by probing the complex and multi-dimensional compositional space that has never been explored before.

Light absorption and radiative forcing of black carbon (BC) is influenced by both BC itself and its interactions with other aerosol chemical compositions. Although the changes in BC concentrations in response to emission reduction measures have been well documented, the influence of emission reductions on the light absorption properties of BC and its influence on BC-boundary-layer interactions has been less explored. In this study, we used the online coupled WRF-Chem model to examine how emission control measures during the Asia-Pacific Economic Cooperation (APEC) summit affect the mixing state and light absorption of BC, and the associated implications for BC-PBL interactions. We found that both the mass concentration of BC and the BC coating materials declined during the APEC week, which reduced the light absorption and light absorption enhancement (Eab) of BC. The reduced absorption aerosol optical depth (AAOD) during APEC was caused by both the decline in the mass concentration of BC itself (52.0 %), and the lensing effect of BC (48.0 %). The reduction in coating materials (39.4 %) contributed the most to the influence of the lensing effect, and the reduced light absorption capability (Eab) contributed 3.2 % to the total reduction in AAOD. Reduced light absorption of BC due to emission control during APEC enhanced planetary boundary layer height (PBLH) by 8.2 m. PM2.5 and O3 were found to have different responses to the changes in the light absorption of BC. Reduced light absorption of BC due to emission reductions decreased near-surface PM2.5 concentrations but near-surface O3 concentrations were enhanced in the North China Plain. These results suggest that current measures to control SO2, NOx, etc. would be effective in reducing the absorption enhancement of BC and in inhibiting the feedback of BC on the boundary layer. However, enhanced ground O3 might be a side effect of current emission control strategies. How to control emissions to offset this side effect of current emission control measures on O3 should be an area of further focus.

Abstract Using 10.1 × 109 J/ψ events produced by the Beijing Electron Positron Collider (BEPCII) at a center-of-mass energy s $$ \sqrt{s} $$ = 3.097 GeV and collected with the BESIII detector, we present a search for the rare semi-leptonic decay J/ψ → D − e + ν e + c.c. No excess of signal above background is observed, and an upper limit on the branching fraction ℬ(J/ψ → D − e + ν e + c. c.)

Abstract By using 6.32 fb −1 of data collected with the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, we perform an amplitude analysis of the decay D s + → K S 0 π + π 0 $$ {D}_s^{+}\to {K}_S^0{\pi}^{+}{\pi}^0 $$ and determine the relative fractions and phase differences of different intermediate processes, which include K S 0 ρ $$ {K}_S^0\rho $$ (770)+, K S 0 ρ $$ {K}_S^0\rho $$ (1450)+, K *(892)0 π +, K *(892)+ π 0, and K *(1410)0 π +. With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be ℬ D s + → K S 0 π + π 0 = 5.43 ± 0.30 stat ± 0.15 syst × 10 − 3 $$ \mathrm{\mathcal{B}}\left({D}_s^{+}\to {K}_S^0{\pi}^{+}\pi 0\right)=\left(5.43\pm {0.30}_{\mathrm{stat}}\pm {0.15}_{\mathrm{syst}}\right)\times {10}^{-3} $$ .

Dissimilar TC4 titanium alloy and 316L stainless steel were successfully joined utilizing thermoplastic bonding (TPB) with a Ti-based bulk metallic glass (BMG) as the filler. Good physical pre-bonding and metallurgical bonding were successively achieved through superplastic flowing in the superliquid region and solid-sate atomic diffusion and reaction. The experimental results indicated that the superplastic flow of BMG in the superliquid region greatly promoted void shrinkage in the interfaces. Hence, a compact contacting was obtained at temperature much lower than the melting point of the filler metal, which is beneficial to the atomic diffusion between the filler metal and base metals as temperature increased. After holding for some time below the melting point of the filler metal, three different reaction layers derived from the atomic diffusion and reaction between the base metal and filler metal were formed in the interfacial regions. A series of irregular bulky and small plate-shaped fine phases were formed and uniformly distributed in the interfacial regions and intermediate region. The shearing tests showed that a high strength of 225 MPa was obtained after diffusing at 695 °C for 60min. The fracture surface of the joint shifted from the 316L interface to then central crystallization layer as temperature increased.

The blade vortex evaluation in Francis Turbine under deep part load conditions generates severe pressure ‎fluctuations in the runner. The complex flow in a model turbine is numerically investigated based on a ‎modified Partially Averaged Navier-Stokes method. The main emphasis is focused on revealing the ‎correlation mechanism of blade vortex evolution and energy production. The results indicate that the ‎modified PANS method shows significant advantages in hydro turbine’s simulation than the traditional ‎RANS method. At deep part load conditions, the vorticity formed at the leading edge of the suction ‎surface and the trailing edge of the pressure surface in the blade channels. The stretching term provides ‎the most vorticity increments while the dilation term inhibiting part which only provides a decrement of ‎the vorticity evolution. Based on the entropy production theory, the total entropy production distribution ‎is consisting with the distribution of vorticity. At deep part load condition, direct dissipation and turbulent ‎dissipation provide the most entropy, while at part load condition the proportion of these two-part ‎decreased‎.

Abstract We report the first measurement of the absolute branching fraction of the inclusive decay $$\Lambda _c^+ \rightarrow K_S^0X$$ Λ c + → K S 0 X . The analysis is performed using an $$e^+e^-$$ e + e - collision data sample corresponding to an integrated luminosity of 567 $$\hbox {pb}^{-1}$$ pb - 1 taken at $$\sqrt{s}$$ s = 4.6 GeV with the BESIII detector. Using eleven Cabibbo-favored $${\bar{\Lambda }}_c^-$$ Λ ¯ c - decay modes and the double-tag technique, this absolute branching fraction is measured to be $${\mathcal {B}}(\Lambda _c^+ \rightarrow K_S^0X)=(9.9\pm 0.6\pm 0.4)\%$$ B ( Λ c + → K S 0 X ) = ( 9.9 ± 0.6 ± 0.4 ) % , where the first uncertainty is statistical and the second systematic. The relative deviation between the branching fractions for the inclusive decay and the observed exclusive decays is $$(18.7\pm 8.3)\%$$ ( 18.7 ± 8.3 ) % , which indicates that there may be some unobserved decay modes with a neutron or excited baryons in the final state.

OpenStreetMap (OSM) is a free map of the world which can be edited by global volunteers. Existing studies have showed that completeness of OSM road data in some developing countries (e.g. China) is much lower, resulting in concern in utilizing the data in various applications. But very few have focused on investigating what types of road are still poorly mapped. This study aims not only to investigate the completeness of OSM road datasets in China but also to investigate what types of road (called omission roads) have not been mapped, which is achieved by referring to both Street Map and Street View. Sixteen prefecture-level divisions in the urban areas of Hubei (China) were used as study areas. Results showed that: (1) the completeness for most prefecture-level divisions was at a low-to-medium level; most roads (in the Street Map), however, with traffic conditions had already been mapped well. (2) Most of the omission OSM roads were either private roads, or public roads not having yet been named and with only one single lane, indicating their minor importance in the urban road network. We argue that although the OSM road datasets in China are incomplete, they may still be used for several applications such as traffic flow analysis, road map representation, and backbone structure detection.

Using e+e− collision data at ten center-of-mass energies between 2.644 and 3.080 GeV collected with the BESIII detector at BEPCII and corresponding to an integrated luminosity of about 500 pb−1, we measure the cross sections and effective form factors for the process e+e−→Ξ0Ξ¯0 utilizing a single-tag method. A fit to the cross section of e+e−→Ξ0Ξ¯0 with a pQCD-driven power function is performed, from which no significant resonance or threshold enhancement is observed. In addition, the ratio of cross sections for the processes e+e−→Ξ−Ξ¯+ and Ξ0Ξ¯0 is calculated using recent BESIII measurement and is found to be compatible with expectation from isospin symmetry.

Using 5.9 pb−1 of e+e− annihilation data collected at center-of-mass energies from 3.640 to 3.701 GeV with the BESIII detector at the BEPCII Collider, we measure the observed cross sections of e+e−→KS0X (where X=anything). From a fit to these observed cross sections with the sum of continuum and ψ(3686) and J/ψ Breit-Wigner functions and considering initial state radiation and the BEPCII beam energy spread, we obtain for the first time the product of ψ(3686) leptonic width and inclusive decay branching fraction Γψ(3686)eeB(ψ(3686)→KS0X)=(373.8±6.7±20.0) eV, and assuming Γψ(3686)ee is (2.33±0.04) keV from PDG value, we measure B(ψ(3686)→KS0X)=(16.04±0.29±0.90)%, where the first uncertainty is statistical and the second is systematic.

Shadows are ubiquitous in high-resolution images, especially in urban regions where there are more serious shadow occlusions. In order to improve the detection effect of shadows, this paper analyzes the characteristics and properties of shadows in orthophotos, and proposes an orthophoto shadow detection method under artificial shadow. Firstly, the shadow modeling tool is used to calculate the shadow regions (i.e. artificial shadow) caused by the building obstructing the sun's rays. Secondly, the relaxation matching algorithm is extended by the position and the shape of the shadow polygon as characteristic constraints. The relaxation matching algorithm is extended by the position and shape as shadow polygon’s characteristic constraints. Thirdly, the feature constraint value is calculated which between the shadow polygons of the two images. The correlation coefficient is used to obtain the initial probability value of each shadow polygon in the orthophoto. Finally, the optimal solution is obtained by continuous correction and iteration of the initial probability value. The method performs an overall matching of the two images and obtains the position of the shadow regions of the buildings in the orthophoto image. Experiment shows that this method reduces the mismatch rate and improves the matching accuracy. This method can detect shadow regions of buildings in orthophoto quickly and efficiently.

Due to the semi-random characteristics of ground points collected by airborne LIDAR system, it is difficult to control the laser pin points to fall on the control points with known coordinates in actual measurement, so the accuracy can not be evaluated by directly comparing coordinate data. In this paper, based on the target plate designed by air-to-ground, the fuzzy c-means clustering analysis algorithm is proposed to extract the point cloud data on the target according to the different echo intensity data of laser on different ground objects. The center point coordinates of the target were fitted by the point cloud data on the target using the method of circumscribed circle of edge points, so as to realize the plane precision and elevation accuracy of airborne LIDAR system of evaluation. The results show that the model fitting method can quickly and effectively evaluate the accuracy of airborne LIDAR, and the method is simple and feasible.

As one of the most popular surveillance technologies in the 21st century, Lidar is applied in commercial, military and civilian applications. paper mainly introduces the development process of Chinese and American marine lidar detection technology, compares the hardware technical parameters of marine airborne laser lidar between China and the United States, and summarizes China's current airborne lidar detection technology and developed countries. Find the gap between developed countries. It introduces the most important application of this technology, and its contribution to the development of science and technology. Finally, summarize the various problems encountered in the development of the technology, analyse the reasons, and look forward to the future development trend.

Optical property parameters play an important role in ocean colour studies. As a key variable, the absorption coefficient is of great significance for calculating the content of each component in water and simulating the physical, chemical and biological properties of water. The inversion algorithms mainly include empirical model, semi-analytical model and neural network model. In this study, we focused on the QAA_V6, which is the newest version of Quasi-Analytical Algorithm (QAA). It is necessary to test the QAA_V6 model in different conditions. IOCCG data set is used to verify the accuracy of QAA_V6. Additionally, MODIS data of case 1 waters and case 2 waters were selected. After extraction and matching, the data was finally imported into QAA_V6 model to calculate the absorption coefficient with a R2 of 0.999 in both case 1 waters and case 2 waters, thus the QAA_V6 model showed a high accuracy and robust applicability in the inversion of inherent optical properties. Subsequently, it can be further verified for the waters in more complicated areas, providing a firm foundation for implementing QAA into the research of ocean colour remote sensing.

Although many efforts have been made on the extraction of houses from LiDAR (Light Detection and Ranging) and/or aerial imagery and/or their fusion, little investigation using co-registration between the orthoimage map and LiDAR on the basis of geodetic coordinates as element for house extraction. For this reason, this paper first overviews the advances of LiDAR and investigates the advantages and disadvantages of LiDAR system vs. traditional photogrammetry, and then indicates that LiDAR technology has not yet resolved all existing problems that traditional photogrammetry remained so far, such as texture information, LiDAR point cloud density. A comprehensive comparison in extraction of houses (feature information) from LiDAR data set and from aerial imagery are also presented. It has been widely accepted and admitted that full automation for extraction of houses (feature information in city area) from LiDAR point cloud has still been difficult. Therefore, this paper proposes a human-computer interaction operation for houses extraction through combination of LiDAR point cloud and the orthorectified high-resolution aerial imagery. The real data is utilized for validation of the proposed method.

In order to solve the problem that the source of LiDAR data error needs to be adjusted and the data volume is large, the adjustment speed between the voyages is slow and cannot be automatically adjusted. Based on the iterative nearest point (ICP) algorithm, this paper proposes an improved iterative closest point (ICP) algorithm based on GPU parallel octree. The algorithm quickly constructs the octree of LiDAR nautical belt data in the GPU, uses the octree to quickly find the overlapping area of the nautical band, and then uses the ICP algorithm in the overlapping area to solve the adjustment parameters R and T quickly. Then the entire flight belt is quickly adjusted. Experiments with example data show that this method can quickly and automatically adjustment a large number of LiDAR data, and the adjustment precision can meet the precision requirements of the production.

Although contemporary geospatial science has made great progress, spatial data fusion of vector and raster data is still a problem in the geoinformation science environment. In order to solve the problem, this paper proposes a method which merges vector and raster data. Firstly, the row and column numbers of the raster data, and the X, Y values of the vector data are represented by Morton code in the C++ environment, respectively. Secondly, we establish the the raster data table and the vector data table in the Oracle database to store the vector data and the raster data. Third, this paper uses the minimum selection bounding box method to extract the top data of the building model. Finally, we divide the vector and raster data into four steps to obtain the fusion data table, and we call the fusion data in the database for 3D visualization. This method compresses the size of data of the original data, and simultaneously divides the data into three levels, which not only solves the problem of data duplication storage and unorganized storage, but also can realize vector data storage and the raster data storage in the same database at the same time. Thus, the fusion original orthophoto data contains the gray values of building roofs and the elevation data, which can improve the availability of vector data and the raster data in the 3D Visualization application.

At present, the main LiDAR is single-point lidar. APD arrays and laser arrays are restricted to exit, so the number of area array LiDAR is scarce. Single-point lidar can't form a scanning pattern with only one laser point on the ground after launching laser, so it must have a set of scanning device for single-point lidar. The scanning device designed in this paper forms a circular scanning area on the ground by rotating the refraction prism, and at the same time forms a conical field of view. At present, marine LiDAR uses this kind of scanner more frequently. The advantages of this scanner are: simple mechanical structure and smooth operation. Overlapping elliptical scanning trajectories can be obtained during flight, which increases scanning density. Ultra-low dispersion glass is used as refractive prism in this paper. In a certain range of laser frequencies, the refractive prism has almost the same effect on laser refraction at different frequencies. The simulation results show that the scanner can be used as a common LiDAR scanner or a dual-frequency LiDAR scanner.

Karst rocky desertification (KRD) is used to characterize the processes that transform a karst area covered by vegetation and soil into a rocky landscape almost devoid of soil and vegetation. This situation seriously affects and threatens the living environment and standards of local people, which results in a series of social problems. In view of the importance and harmfulness of KRD, many scholars have studied the spatial and temporal evolution of KRD and its driving forces. In this paper, the Visual Interpretation Marks of Rocky Desertification in Southwest China in 1960s are constructed by using the DISP image of the United States, combined with DEM data and Hydrogeological data. The area of rocky desertification in Guangnan and Funing counties, where rocky desertification is more serious, is about 2457.729 km2. The area of rocky desertification can be used as the basic data for studying the historical changes in southwestern China by researchers.

The evaluation of the bathymetric capability of traditional airborne lidar system is mostly based on the formula of bathymetric capability by evaluating the diffuse attenuation coefficient (Kd). This method is derived form the assumption that the reflectance of sediment is fixed. In this study ,however,the reflectance of sediment is not fixed. Therefore, this study improves the ability of bathymetric formula, and proposes a particle scattering classification algorithm to obtain the transmissivity value. The algorithm filters the scattering modes of particles by scattering discrimination factor (q), and obtains the transmissivity values by using the scattering intensity formulas. Experiments show that, when the transmissivity is in the range of 0–1 and the average values of Kd(532 nm) are 0.1150 m−1, 0.0894 m−1 and 0.0903 m−1 in January, June and October respectively, accordingly, the bathymetric capabilities are 0–44 m, 0–61.5 m and 0–52.5 m, respectively. Compared with the original bathymetric method, these results show that the maximum bathymetric value has measured by the improved bathymetric capability formula and scattering classification algorithm has decreased under the influence of the change of sediment reflectance, and the result is more consistent with the actual situation and more accurate.

Due to the influence of the occlusion of objects or the complexity of the measured terrain in the scanning process of airborne lidar, the point cloud data inevitably appears holes after filtering and other processing. The incomplete data will inevitably have an impact on the quality of the reconstructed digital elevation model, so how to repair the incomplete point cloud data has become an urgent problem to be solved. To solve the problem of hole repair in point cloud data, a hole repair algorithm based on improved moving least square method is proposed in this paper by studying existing hole repair algorithms. Firstly, the algorithm extracts the boundary of the point cloud based on the triangular mesh model. Then we use k-nearest neighbor search to obtain the k-nearest neighbor points of the boundary point. Finally, according to the boundary point and its k-nearest neighbor point, the improved moving least squares method is used to fit the hole surface to realize the hole repair. Combined with C++ and MATLAB language, the feasibility of the algorithm is tested by specific application examples. The experimental results show that the algorithm can effectively repair the point cloud data holes, and the repairing precision is high. The filled hole area can be smoothly connected with the boundary.

Aiming at the problems of low accuracy and slow speed in the current remote sensing image classification algorithm,In order to improve remote sensing image classification, a quantum entanglement algorithm is proposed.The model transforms the classification process of remote sensing image into a random self-organization process of quantum particles in the state configuration space. The state configuration formed by entanglement of quantum particles evolves with time and finally converges to an average probability distribution.Taking Kunming city of Yunnan province as the research area, this paper compares the classification method in this paper with the traditional remote sensing classification method by using the 02C image data of yuanyuan1.Compared with other classification methods, the classification accuracy of this paper meets the requirements.

This paper mainly uses manual calibration technology to check the elements Yaw, Pitch and Roll (YPR) in the LiDAR DGPS/IMU system and obtained the error value. Combined with the error angle, the external azimuth angle elements Kappa, Omega and Phi required by photogrammetry are obtained. The paper points out that the placement angle error will have a serious impact on the LiDAR foot position. Therefore, this paper puts forward a method to check the placement angle of the steeple roof and flat straight highway, and gives the design scheme of the optimized route to reduce the number of flights. This paper focuses on the specific process of YPR calibration, and gives a mathematical calibration model based on the influence of attitude angles Yaw, Pitch and Roll on the LiDAR foot during the flight. The placement angle error is obtained after the calibration, and the error angle matrix is used to convert the elements YPR and OPK. After checking and error correction, the point cloud obtained from adjacent airlines have achieved better coincidence effect. The experimental results show that the theory and method of YPR element calibration are correct and feasible, which simplifies the conversion process of YPR and OPK. Compared with the traditional calibration method that requires control points, this method can greatly improve the efficiency and reliability of the inspection.

In the exploration of outer space and international space activities, civilian remote sensing satellites have made rapid development since the 1970s, and countries around the world have accelerated their civilian satellite development and its policy formulation as well. Regarding the regulations on the peaceful use of outer space and related space launches, the United Nations respectively formulated the "Five Treaties on Space" in the 1960s and 1970s to regulate the peaceful uses of outer space. However, in the development of civilian remote sensing satellites, orbital resources and application rules of remote sensing data, the implementation of "first-come, first-occupy" and "non-discriminatory access to remote sensing data" is mainly led by western developed countries, especially the space powers such as the United States and Russia. Based on the outer space policies and regulations, this article will make a comparative study of civilian remote sensing satellite development policies and related laws and regulations in major countries and regions in the world, so as to analyze the policies and legal principles of civilian remote sensing satellites, as well as its corresponding issues and problems.

There are many intertidal zones and island reefs in the coastal area, the traditional shipborne acoustic measurement method is extremely inefficient, so the coastal area three-dimensional integrated measurement has always been a difficult point in the field of remote sensing. Because the sea blue-green light window has good transparency and the laser point cloud data can quickly and accurately distinguish the characteristics of shallow sea water topography. At present, the most effective detection method for coastal areas in the world is the airborne dual-frequency laser radar detection technology, which has high measurement rate and wide coverage. The laser outputs both 1064nm and 532nm dual-wavelength laser, 1064nm laser forms sea surface echo, and 532nm laser penetrates sea water to form shallow sea and deep sea echo. However, during the propagation of seawater, the number of photon scattering increases with the increase of water depth, which will cause the attenuation of the echo signal. As a result, the detection of weak light in the large dynamic range is not high, which has been a difficult point for near-shore airborne sounding. To solve this problem, we designed a split-field, three-channel optical receiving system. The ZEMAX simulation results show that the dual-channel laser radar three-channel receiving optical system effectively reduces the optical crosstalk between the optical components and the channels, and achieves energy harvesting in different water depth channels. The structure dynamically compresses the photoelectric signal and improves the signal to noise ratio.

There are some problems in the visualization of 3D model of buildings at present, such as redundant texture data and large memory occupation of loading texture data, which pose challenges to the smooth loading of 3D building visualization. In this paper, we propose a method which using fractal quadtrees to simplify texture data and compress management. Firstly, this method uses the fractal self-similarity and the feature that the same texture has the same fractal dimension to screen all the textures, when the fractal dimension of multiple textures is within the threshold range. Radon transform will be performed on these textures to calculate their standard deviation and further simplify the texture. Secondly, we use fractal texture compression to create a multi-resolution texture data structure with quadtree structure, so that the building 3D model can achieve dynamic visualization of different scales. Finally, the parallel texture mapping of all faces of the 3D model of the building is implemented according to the texture calling rules. Experimental results demonstrate that the texture is managed by the method proposed in this paper, which shortens the loading time of texture and reduces the memory occupation by about 48.92%. Therefore, the method of texture simplification and compression proposed in this paper has a significant effect in the process of building 3D model visualization.

We have designed a method for testing the quality of multidecadal analyses of sea surface temperature (SST) in regional seas by using a set of high-quality local SST observations. In recognizing that local data may reflect local effects, we focus on the dominant empirical orthogonal functions (EOFs) of the local data and of the localized data of the gridded SST analyses. We examine the patterns, variability, and trends of the principal components. This method is applied to examine three different SST analyses, i.e., HadISST1, ERSST, and COBE SST. They have been assessed using a newly constructed high-quality dataset of SST at 26 coastal stations along the Chinese coast in 1960–2015, which underwent careful examination with respect to quality and a number of corrections for inhomogeneities. The three gridded analyses perform generally well from 1960 to 2015, in particular since 1980. However, for the pre-satellite period prior to the 1980s, the analyses differ among each other and show some inconsistencies with the local data, such as artificial break points, periods of bias, and differences in trends. We conclude that gridded SST analyses need improvement in the pre-satellite period (prior to the 1980s) by reexamining in detail archives of local quality-controlled SST data in many data-sparse regions of the world.

Phononic materials structured at the macro- or nano-scale are at the forefront of materials research for controlling transport of sound and heat, respectively. Besides the structure length scale, the exact geometry has been found to be of relevance as well. In this work, we provide an extensive finite element investigation of the effect of the shape of periodically dispersed inclusions in a 2D matrix on propagation and attenuation of an acoustic wave packet. We show that, by significantly complexifying the shape from circular to fractal-like (dendrite shape), phonon scattering at wavelengths comparable with the inner structure of the inclusion is enhanced, leading to a strong attenuation that can be fitted by a compressed exponential function, while in the circular case, the diffusive regime is observed.