Search

Roadheader is an engineering robot widely used in underground engineering and mining industry. Interactive dynamics simulation of roadheader is a fundamental problem in unmanned excavation and virtual reality training. However, current research is only based on traditional animation techniques or commercial game engines. There are few studies that apply real-time physical simulation of computer graphics to the field of roadheader robot. This paper aims to present an interactive physically-based simulation system of roadheader robot. To this end, an improved multibody simulation method based on generalized coordinates is proposed. First, our simulation method describes robot dynamics based on generalized coordinates. Compared to state-of-the-art methods, our method is more stable and accurate. Numerical simulation results showed that our method has significantly less error than the game engine in the same number of iterations. Second, we adopt the symplectic Euler integrator instead of the conventional fourth-order Runge-Kutta (RK4) method for dynamics iteration. Compared with other integrators, our method is more stable in energy drift during long-term simulation. The test results showed that our system achieved real-time interaction performance of 60 frames per second (fps). Furthermore, we propose a model format for geometric and robotics modeling of roadheaders to implement the system. Our interactive simulation system of roadheader meets the requirements of interactivity, accuracy and stability.

Seismic signal denoising is the main task of seismic data processing. This study proposes a novel method for the denoising seismic record on the basis of a two-dimensional variational mode decomposition (2D-VMD) algorithm and permutation entropy (PE). 2D-VMD is a recently introduced adaptive signal decomposition method in which $K$ and $\alpha $ are important decomposing parameters to determine the number of modes, and have a predictable effect on the nature of detected modes. We present a novel method to address the problems of selecting appropriate $K$ and $\alpha $ values and apply these values to the proposed method. First, for a 2D seismic signal, the 2D-VMD method can decompose it into $K$ modes with specific direction and vibration characteristics. Next, the PE value of each mode is calculated. Random noise components are eliminated according to the PE value. Finally, the signal components are reconstructed to acquire the denoised seismic signal. Experimental and simulation results indicate that the proposed method has remarkable denoising effect on synthetic and real seismic signals. We hope that this new method can inspire and help evaluate new ideas in this field.

In the domain of geotechnical engineering analysis, fast Lagrangian analysis based on the finite difference method is the most commonly used numerical analysis method. It is a classical numerical algorithm applied to calculate the in situ stress. In this paper, we propose a deep learning (DL) architecture called the enhance-and-split feature capsule network embedded in fully convolutional neural networks (ES-Caps-FCN) to predict the in situ stress for a strain-softening model when using the finite difference method for the numerical computation. Experiments indicate that this novel approach is stable and convergent. Compared with some classical prediction methods including linear regression analysis and a deep neural network, the mean squared error of our proposed algorithm is as low as 0.059866%, which is lower than the 0.616676% of the deep neural network prediction algorithm and the 0.978495% of the conventional machine learning algorithm. Additionally, the calculation efficiency of fully trained deep learning models is superior to that of the conventional finite difference method. Therefore, DL is a feasible and promising fast and accurate surrogate for the finite difference method for solving the in situ stress.

In the process of 3D modeling of geological body with fault, it is the primary problem to calculate the intersecting line between fault plane and various geological models. To quickly locate geological models intersecting fault planes, this paper adopts the algorithm of intersection detection of hybrid bounding boxes. Firstly, the principal component analysis is used to generate the bounding box of the tightly bounding geological model. Then, based on the separation axis theorem, an improved algorithm is proposed to realize the intersection detection of hybrid bounding boxes, which effectively reduces the number of detection and improves the efficiency. Experimental results show that this algorithm can greatly shorten the time of intersection test, and improve the efficiency of intersection calculation. This paper provides an algorithm basis for quickly locating the geological model cut by fault plane.

Salvia miltiorrhiza-Dalbergia odorifera coupled-herbs (SMDOCH) has been used to treat coronary heart disease (CHD) for thousands of years, but its unclear bioactive components and mechanisms greatly limit its clinical application. In this study, for the first time, we used network pharmacology to elucidate the mechanisms of action of SMDOCH on CHD. We collected 270 SMDOCH-related targets from 74 bioactive components and 375 CHD-related targets, with 58 overlapping common targets. Next, we performed enrichment analysis for common-target network and protein-protein interaction (PPI) network. The results showed that SMDOCH affected CHD mainly through 10 significant signaling pathways in three biological processes: ‘vascular endothelial function regulation’, ‘inflammatory response’, and ‘lipid metabolism’. Six pathways belonged to the ‘vascular endothelial function regulation’ model, which primarily regulated hormone (renin, angiotensin, oestrogen) activity, and included three key upstream pathways that influence vascular endothelial function, namely KEGG:04933, KEGG:05418, and KEGG:04066. Three pathways, namely KEGG:04668, KEGG:04064, and KEGG:04620, belonged to the ‘inflammatory response’ model. One pathway (KEGG:04920) belonged to the ‘lipid metabolism’ model. To some extent, this study revealed the potential bioactive components and pharmacological mechanisms of SMDOCH on CHD, and provided a new direction for the development of new drugs for the treatment of CHD.

The scutellum, coleoptile, coleorhiza, and epiblast (if it exists) consist of a complex embryonic envelope to protect the plumule and radicle inside a grass embryo. Controversies have been provoked for centuries regarding homologies of the grass embryonic structures. Here we found that the rice LEAFY COTYLEDONE1 (LEC1) gene, OsNF-YB7, is vital for embryo development. A leaf-like structure (LL) was developed from the scutellum of osnf-yb7 to replace the embryonic envelope that formed in wild-type. Additionally, osnf-yb7 developed chloroembryos due to overactivated chlorophyll biosynthesis. Thus, OsNF-YB7 likely plays a dual role in chlorophyll biogenesis in rice embryos: (1) OsNF-YB7 directly represses genes, such as rice GOLDED-LIKE1 (OsGLK1), involving chlorophyll biosynthesis; (2) OsNF-YB7 binds to OsGLK1 to repress the downstream genes of OsGLK1. Parallel phenotypes shown in osnf-yb7 and lec1 suggest functional conservation of the LEC1-type genes in plants. Both lec1 cotyledons and osnf-yb7 LL displayed true leaf characteristics. Our morphological and transcriptional evidence implied that LL replaces the embryonic envelope in osnf-yb7, raising the hypothesis that the grass embryonic envelope is an analog of Arabidopsis cotyledon. This study demonstrates that OsNF-YB7 acts as a negative regulator in chlorophyll biogenesis and is important for embryonic envelope formation.

Dalbergia Odorifera (DO) has been widely used for the treatment of cardiovascular and cerebrovascular diseasesinclinical. However, the effective substances and possible mechanisms of DO are still unclear. In this study, network pharmacology and molecular docking were used toelucidate the effective substances and active mechanisms of DO in treating ischemic stroke (IS). 544 DO-related targets from 29 bioactive components and 344 IS-related targets were collected, among them, 71 overlapping common targets were got. Enrichment analysis showed that 12 components were the possible bioactive components in DO, which regulating 9 important signaling pathways in 3 biological processes including ‘oxidative stress’ (KEGG:04151, KEGG:04068, KEGG:04915), ‘inflammatory response’(KEGG:04668, KEGG:04064) and ‘vascular endothelial function regulation’(KEGG:04066, KEGG:04370). Among these, 5 bioactive components with degree≥20 among the 12 potential bioactive components were selected to be docked with the top5 core targets using AutodockVina software. According to the results of molecular docking, the binding sites of core target protein AKT1 and MOL002974, MOL002975, and MOL002914 were 9, 8, and 6, respectively, and they contained 2, 1, and 0 threonine residues, respectively. And some binding sites were consistent, which may be the reason for the similarities and differences between the docking results of the 3 core bioactive components. The results of in vitro experiments showed that OGD/R could inhibit cell survival and AKT phosphorylation which were reversed by the 3 core bioactive components. Among them, MOL002974 (butein) had a slightly better effect. Therefore, the protective effect of MOL002974 (butein) against cerebral ischemia was further evaluated in a rat model of middle cerebral artery occlusion (MCAO) by detecting neurological score, cerebral infarction volume and lactate dehydrogenase (LDH) level. The results indicated that MOL002974 (butein) could significantly improve the neurological score of rats, decrease cerebral infarction volume, and inhibit the level of LDH in the cerebral tissue and serum in a dose-dependent manner. In conclusion, network pharmacology and molecular docking predicate the possible effective substances and mechanisms of DO in treating IS. And the results are verified by the in vitro and in vivo experiments. This research reveals the possible effective substances from DO and its active mechanisms for treating IS and provides a new direction for the secondary development of DO for treating IS.

Background: Aidi injection (ADI)is a Chinese patent medicine with anti-cancer effect, which has been used to treat breast cancer (BC) in China for many years, but its potential pharmacological mechanism is still indeterminacy. In this resaearch, network pharmacology, a systematic and comprehensive approach, was used to reveal ADI's potential pharmacological mechanism in treating BC for the first time.Methods: Databases were used to collect targets related to the bioactive components of ADI and BC. the relevant networks were established by the string database, and were screened potential bioactive components and core targets. Eventually, core targets and pathway enrichment were analyzed by DAVID database.Results: As the results showed, we collected 99 bioactive ingredients,345 ADI-related targets after deduplication and 368 BC-related targets. Of these, 108 common targets were overlapped. We then performed an enrichment analysis on the common target network and the protein-protein interaction (PPI) network.Conclusion: The results showed that ADI may inhibit breast cancer through seven important signal pathways involved in the "regulation of vascular endothelial function", "inflammatory response" and "apoptosis” biological processes. Through further clustering and enrichment analysis of the PPI network of ADI’s bioactive component targets and BC-related targets, we found that cancer, ErbB, MAPK, TLR, chemokine, p53 and cell cycle signaling pathway, mainly contributed to the effects of ADI in treating BC. In conclusion, this study reveals the possible mechanism of ADI in treating BC, and provides a new direction for drug development for ADI in treating BC.

With the development of information technology, more and more people use multimedia conference system to communicate or work across regions. In this article, an ultra-reliable and low-latency solution based on Deep Learning and assisted by Cloud Computing for multimedia conference system, called UCCMCS, is designed and implemented. In UCCMCS, there are two-tiers in its data distribution structure which combines the advantages of cloud computing. And according to the requirements of ultra-reliability and low-latency, a bandwidth optimization model is proposed to improve the transmission efficiency of multimedia data so as to reduce the delay of the system. In order to improve the reliability of data distribution, the help of cloud computing node is used to carry out the retransmission of lost data. the experimental results show UCCMCS could improve the reliability and reduce the latency of the multimedia data distribution in multimedia conference system.

Boolean operations are an essential tool for creating complex entities in many fields. In order to implement complex entity modeling, we proposed a method based on robust Boolean operations that focused on the robustness of geometric calculations caused by computational errors and data error. This method used a uniform logical judgment to analyze the specific conditions of the intersection of vertices or edges in advance, and avoided the inconsistency between logical judgment results and geometric relations. We correspondingly obtained the positions of the two triangles, the validity of the intersection and the intersection edges from tetrahedral-volume calculations, the triangle-area calculations, and the topology information to mark the triangles instead of intersecting lines tracking and the judgment of the triangles inside the entities. Finally, the experimental results indicate that this method realized the three-dimensional modeling of any complex geological body.

With the development of information technology, more and more people use multimedia conference system to communicate or work across regions. In this article, an ultra-reliable and low-latency solution based on Deep Learning and assisted by Cloud Computing for multimedia conference system, called UCCMCS, is designed and implemented. In UCCMCS, there are two-tiers in its data distribution structure which combines the advantages of cloud computing. And according to the requirements of ultra-reliability and low-latency, a bandwidth optimization model is proposed to improve the transmission efficiency of multimedia data so as to reduce the delay of the system. In order to improve the reliability of data distribution, the help of cloud computing node is used to carry out the retransmission of lost data. the experimental results show UCCMCS could improve the reliability and reduce the latency of the multimedia data distribution in multimedia conference system.

With the continuous deepening of the reform of the cadre personnel system in our country and the increasing frequency of talent flow, the traditional cadre personnel file management model faces new challenges. This paper analyzes the importance and existing problems of the management of personnel files of cadres in colleges and universities with computer aided technology, and puts forward countermeasures for the management of cadres’ personnel files from aspects of hardware construction, staffing, sound system, standardized management, promotion of informatization, and improvement of utilization rate.

With the continuous deepening of the reform of the cadre personnel system in our country and the increasing frequency of talent flow, the traditional cadre personnel file management model faces new challenges. This paper analyzes the importance and problems of digital technology in the management of cadre and personnel files in colleges and universities, and puts forward countermeasures for the management of cadres’ personnel files from aspects of hardware construction, staffing, sound system, standardized management, promotion of informatization, and improvement of utilization rate.

Macrophages play important roles in the healing and remodeling of cardiac tissues after myocardial ischemia/reperfusion (MI/R) injury. Here we investigated the potential effects of salvianolic acid B (SalB), one of the abundant and bioactive compounds extracted from Chinese herb Salvia Miltiorrhiza (Danshen), on macrophage-mediated inflammation after MI/R and the underlying mechanisms. In primary cultured bone marrow-derived macrophages (BMDMs), SalB attenuated lipopolysaccharide (LPS)-induced M1 biomarkers (IL-6, iNOS, CCL2 and TNF-α) mRNA expression in a concentration-dependent manner. In contrast, M2 biomarkers (Arg1, Clec10a and Mrc) mRNA levels following interleukinin-4 (IL-4) stimulation were significantly upregulated by SalB. In addition, LPS stimulation potently induced transcriptional upregulation of RagD, an important activation factor of mammalian target of rapamycin complex 1 (mTORC1). Interestingly, SalB inhibited RagD upregulation and mTORC1 activation, decreased glycolysis, and reduced inflammatory cytokine production in LPS-stimulated macrophages, all of which were blunted in RagD knockdown macrophages. In mice subjected to MI/R, SalB treatment decreased cardiac M1-macrophages and increased M2-macrophages at 3 days post-MI/R, followed by decreased collagen deposition and ameliorated cardiac dysfunction at 7 days post-MI/R. Collectively, our data have shown that SalB decreases M1-polarized macrophages in MI/R hearts via inhibiting mTORC1-dependent glycolysis, which might contribute to alleviated inflammation and improved cardiac dysfunction afforded by SalB after MI/R.

Curved surface mesh generation is a key step for many areas. Here, a mesh generation algorithm for closed curved surface based on Delaunay refinement is proposed. We focus on improving the shape quality of the meshes generated and making them conform to 2-manifold. The Delaunay tetrahedralization of initial sample is generated first, the initial surface mesh which is a subset of the Delaunay tetrahedralization can be achieved. A triangle is refined by inserting a new point if it is large or of bad quality. For each sample, we also check the triangles that adjoin it whether from a topological disk. If not, the largest triangle will be refined. Finally, the surface mesh is updated after a new point is inserted into the sample. The definition of mesh size function for surface mesh generation is also put in this paper. Meshing experiments of some models demonstrate that the new algorithm is advantageous in generating high quality surface mesh, the count of mesh is suitable and can well approximate the curved surface. The presented method can be used for a wide range of problems including computer graphics, computer vision and finite element method.

Invasive plants may be attacked both above ground and below ground. Few studies have, however, investigated the simultaneous effects of above-ground and below-ground herbivory. In the present study, we report the effects of beetle herbivory and nematode infection on alligator weed, Alternanthera philoxeroides, an invasive plant in China. We found that the root-knot nematode Meloidogyne incognita widely occurred on the plant in south China. To examine its effect on the plant in conjunction with above-ground herbivory, we conducted a field common garden experiment with a local insect defoliator, Cassida piperata. We also included the native congener Alternanthera sessilis in our experiments for a comparison of the response of invasive and native species. We found no significant effects on plant biomass of the nematode infection in conjunction with the above-ground herbivory. Further chemical analysis, however, showed that the water-soluble carbohydrate content in roots of A. philoxeroides was significantly increased in plants attacked by both the nematode and the herbivore compared with the water-soluble carbohydrate content in plants attacked by only the nematode or herbivore alone. We found no such change in the native congener A. sessilis. Together these results may suggest that A. philoxeroides tolerates joint above-ground and below-ground damage by allocating more resources to below-ground material. © 2010 The Authors. Journal compilation

Mesh generation is a key step for many areas. Here, an adaptive mesh generation algorithm for piecewise linear domains based on constrained Delaunay is proposed. We focus on improving the quality of the meshes generated and make them conforming to an isotropic size function which is specified by the user. The preliminary mesh with boundaries conforming is generated first. We try to add points to split the mesh either bad shape or not conforming to the size function. The new point can be added to the domain only if it is not close to the existing point in the domain. Finally, local meshes are reconstructed to make all meshes comply with the constrained Delaunay. Experimental comparisons show that the new algorithm is advantageous in generating adaptive mesh. The presented method can be used in a wide range of areas such as computer vision, finite element method and many other areas.

Weinvestigatedthedeliveryofsmallclusterionsusingasourceofnegativeionsbycesiumsputtering(SNICS).ThenegativeclusterionsofB n ,C n ,Si n ,Co n ,Cu n ,Ge n ,Au n ,GeB n andSiB n havebeenextractedbySNICS.Adequatebeamcurrentofsomesmallclusterswasobtainedbychangingseveralparametersforclusterionyield.Afteracomprehensivestudyoftheoperationparameters,suchastargetmaterialselection,targetgeometry,sputteringvoltageandcurrent,thesmallclusterioncurrentcanbeincreasedbyseveralordersofmagnitude,withlittlechangeonthemonomerionyield. 2002ElsevierScienceB.V.Allrightsreserved. PACS:36.40.)c;36.40.)Wa;61.46.þWKeywords:Cluster;Clusterion;Cluster–solidinteraction 1.IntroductionIntheearlystageofacceleratorinventionanddevelopment,monomerionsthatweretheprimaryobjectiveforresearch,havebeenfoundaccompa-niedwith annoying molecular-small cluster ions.Forinstance,incapillaryarc-dischargeionsourceforH þ ,theformationofmolecularionsH 2 andH þ3 isveryprobableduetothehighrecombinationcoefficient. In such a capillary arc-discharge ionsource,themonomer-atomicionsisnotmorethan10–20%andthebeamiscomposedmainlyofH

Nuclear reaction, 11B(p,α)8Be, shows great potentials in boron characterization of materials due to its large cross-section at the broad resonance at 660 keV. Unfortunately, the existing cross-section data on this reaction show errors of up to 30% and inconsistency as high as 50%. All previously published cross-sections of this reaction were based on assumptions or on more or less arbitrary convention. We present an accurate measurement of the cross-sections of nuclear reaction 11B(p,α1)8Be* using self-supported 11B foil target, high resolution detection and careful analysis of the α-spectra. An accurate cross-section with α1 was obtained with careful spectrum stripping of α1 from the α12 continuum. Cross-section with α1+α12 under more definite and realistic convention is also given for practical applications. Cross-sections are given in graphical form for θlab=150°.

When high energy heavy ions bombard a single crystal, such as MeV Si implantation in Si, the surface region becomes vacancy-rich, while interstitials are mostly distributed near the range of the implants. We have demonstrated that vacancy retards while interstitial enhances boron thermal diffusion in silicon. In this paper we will show experimental results on the modification of boron diffusivity by point defect engineering, and its application in ultra-shallow junction (10 nm) formation. In this paper, we will also show cluster ion, such as GeB and SiB, implantation in silicon, and two-stage annealing in forming ultra shallow junction in Si. RBS, channeling, nuclear reaction, and secondary ion mass spectrometry are used for this studies.

Due to the spatial and temporal close proximity of cluster ion bombardment on Silicon, radiation damage of Si due to cluster ions cannot be extrapolated from that of atomic ions. In this paper we overview our recent observations of radiation damage in Si by clusters of C and Au aggregates of up to 10 atoms and 4 atoms respectively. Quantification of damage is made by RBS/channeling. We observed hyper linear radiation damage depending on cluster size. We developed a theoretical interpretation of this observation using a collision cascade overlapping model.

To solve the existing problems of the interactive modeling of buildings, a fast, automatic and detailed modeling algorithm is introduced. Through customizing property library, drawing a plane figure of the building and building components, and configuring properties for them, the algorithm could automatically complete the whole modeling process. The three-dimensional model can be automatically modified with the property information of GIS. The algorithm is widely applied into LionKingSoft digital city system and meets the requirements of rapid modeling of the large group of buildings. The experiment results indicate the algorithm is rapid, accurate and practical.

To draw a correct and rational project network diagram automatically is a basic problem that should be solved during the application of network program technology. In view of the problems existing in the project networkdiagram's algorithm for auto-drawing, this paper focused on analyzing a generating mechanism of crosswire in project network diagram and dummy activity in activity-on-arrow. Thus, a heuristic auto-layout algorithm was proposed, which made it possible to generate a one-time project network diagram with exact logical relation, few cross points and few dummy activities without multiple scans. The algorithm greatly has enhanced its efficiency and guaranteed the correctness and rationality of project network diagram.