Search

A well known quotient of the real Stiefel manifold is the projective Stiefel manifold. We introduce a new family of quotients of the real Stiefel manifold by cyclic group of order 2 whose action is induced by simultaneous pairwise flipping of the coordinates. We obtain a description for their tangent bundles, compute their mod 2 cohomology and compute the Stiefel Whitney classes of these manifolds. We use these to provide applications to their stable span, parallelizability and equivariant maps, and some associated results in topological combinatorics. [ABSTRACT FROM AUTHOR]

In a comparative correlative construction, such as The less you read, the stupider you are, the two clauses must both be finite, like a root clause; but neither can stand alone, like a subordinate clause. The construction shares significant formal properties with one type of coordinate construction, such as You drink another can of beer and I'm leaving. The paper argues that a comparative correlative construction and such a coordinate construction have the same syntactic structure. In this structure, a functional element that is directly merged with a conjunct or a modifier occurs. Moreover, the construction-specific formatives, such as the clause-initial the or the Mandarin predicate-initial yue 'more', is analyzed as the result of the spanning of this functional element with another functional element in the clause. Furthermore, the pairing of the formatives in the construction comes from the Double Marking of this functional element. [ABSTRACT FROM AUTHOR]

Testosterone is one of the important hormones involved in various physiological activities including muscle growth, bone density, and libido. In this regard, delivery through niosomes may have potential advantages concerning its bioavailability and stability. Niosomes are vesicles based on non-ionic surfactants, an effective drug delivery system because of the encapsulation of different active pharmaceutical ingredients such as, hydrophilic, hydrophobics, and amphiphilic. In this work, differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, and high-resolution transmission electron microscopy (HRTEM) were employed for the characterization of interactions and testosterone encapsulation in the fabricated niosome formulations. The main purpose of the work is to explain the absence of testosterone peaks in DSC spectra after the formulation of niosomes. Niosomes were prepared by dissolving 1% testosterone powder and different amounts of span60 powder, tween60 semisolid, and cholesterol powder via a modified solvent evaporation method. Besides the various plausible explanations associated with the testosterone peak changes, the few most important ones are solid-state transitions, interaction of the components via hydrogen bonding and van der Waals forces, encapsulation of testosterone, and dilution effect. These solid-state transitions might be polymorphic or transformation to the amorphous state from crystalline, which was also substantiated by the HRTEM images showing the crystalline structure at the center surrounded by an amorphous area. The FTIR data confirmed the testosterone encapsulation within the niosomes based on a chemical structure and functional groups. This analysis highlights the potential of designing stable niosome formulations for testosterone using different ingredients, facilitating its application in nanotechnology using different analysis techniques. [ABSTRACT FROM AUTHOR]

Span-based joint extraction simultaneously conducts named entity recognition (NER) and relation extraction (RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network (STSN), a span-based joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention units. On the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1, creating new state-of-the-art results. [ABSTRACT FROM AUTHOR]

One of the promising and current trends in the design of wide span sprinkling machines is the principle of resource saving. Trends for improving the design and technological parameters of sprinkling equipment based on the principles of resource conservation are considered, and a concept for the development of sprinkling equipment based on operating conditions is formed. The research carried out made it possible to improve the truss structures of the KASKAD model range of sprinkling machines. The reduction in material consumption is based on optimizing the parameters of spans and truss structures, for which coefficients of metal consumption of the truss and the weight of angles were proposed. Improvement of the truss structure made it possible to increase the span length by 22.1–33.8% with a slight increase in mass by 5.8–15.1%. [ABSTRACT FROM AUTHOR]

Over the last decade, millions of 4G and 5G-enabled mobile devices have become part of the Internet. Almost, all the applications have been shifted to smartphones. A person connects his smartphone to several other devices or remote servers for exchanging sensitive data. In this sense, security threats in terms of authentication, data confidentiality, and data integrity are increasing day by day for mobile devices. The asymmetric key cryptosystem is considered more secure, but it is heavyweight for smart devices on the basis of computation and communication costs. The symmetric key cryptosystem is considered lightweight for smart devices in terms of computation and communication overheads, but it is vulnerable to several attacks such as MITM attacks. Several symmetric key security systems have been proposed for smart devices but adopt complex mathematical procedures. Therefore, existing symmetric key security systems increase the computation and communication overheads. In this paper, we propose a lightweight and authentic symmetric key cryptosystem for resource-constrained mobile client–server environments. Our proposed cryptosystem consists of a lightweight symmetric session key exchange algorithm, mutual authentication service, and data confidentiality service, respectively. Moreover, we prove the robustness of our proposed cryptosystem with the help of informal and formal security analysis through the AVISPA tool. In addition, performance evaluation and comparisons with existing security systems show that our proposed cryptosystem is efficient, lightweight, secure, and most suitable for mobile computing. [ABSTRACT FROM AUTHOR]

Deaf signers consistently show shorter memory spans than hearing nonsigners, but the scope and nature of this difference remain unclear. The present study tested whether Deaf signers are biased toward flexible use of visual aspects of linguistic items. Matched samples of adult Deaf signers (N = 33) and hearing nonsigners (N = 32) performed a letter-span task with visual serial presentation, to bias phonological processing, and a simultaneous presentation, to bias visuospatial processing. We also manipulated short-term memory by varying recall direction (forward, backward). Analyses revealed reduced spans for Deaf signers compared with hearing nonsigners, backward compared with forward recall, and sequential compared with simultaneous presentation. Item-level responses indicated that Deaf signers made more errors than hearing nonsigners across three error types. Deaf signers also showed reduced item position binding compared with hearing nonsigners, which indicates differences related to item order and sequencing in tasks with printed, linguistic stimuli. Deaf signers were the only group who demonstrated reduced omission errors when switching from sequential to simultaneous presentation, suggesting flexible processing mechanisms. No group differences were found for a secondary spatial span test, indicating the scope of group differences for ordered information was limited to verbal items. Overall, results are consistent with flexible use of different memory cues in Deaf signers. A core area for future research includes evaluating reduced activation of phonological representations of linguistic items in Deaf signers. These results amplify a novel M3 model approach for evaluating how errors contribute to short-term memory differences in Deaf signers. [ABSTRACT FROM AUTHOR]

This study employs the finite element-based CSiBridge v.20.0.0 software to examine the response of a single-cell prestressed box-girder bridge subjected to Indian loading conditions. The analyses is carried out on a simply supported bridge considering the specifications of Indian Road Congress (IRC) 6:2017, IRC 18:2000 and IRC 21:2000. An existing model of prestressed skewed bridge is validated with the published one. A convergence study is conducted for determining the model's mesh size. An extensive parametric study is carried out to gain a better understanding of the response of a skewed prestressed bridge. The parameters variables are: Skew angle (0°, 10°, 20°, 30°, 40°, 50°, and 60°); Span (35, 40, 45, 50, 55, and 60 m); and Span-depth ratio (10, 12, 14, 16 and 18). The results of this study are presented as ratios of Bending moment, Shear force, Torsional moment, and Vertical deflection. Finally, equations for estimation of these ratios for different span and span-depth ratio are also deduced from the statistical approach so that the results of skewed bridges may be evaluated directly. It is determined that the skewed bridge outperforms the straight bridge because of its higher span-depth ratio, which results in less bending moment development. Evidence suggests that the skewness may help to lessen the prestress load's dominance. The findings of this study may be helpful to engineers and designers in the analysis and design of prestresssed skewed box-girder bridges. [ABSTRACT FROM AUTHOR]

The integrated navigation system is the inertial navigation system (INS), corrected by global navigation satellite system (GNSS) data. The correction could be done algorithmically by utilizing nonlinear Kalman filtering (NKF). In practice, the NKF uses an INS error model as an a priori model that is not always adequate to handle the dynamics of the true and unknown INS error model. To eliminate such modeling errors, we propose a new INS/GPS correction approach with modified adaptive NKF. In the proposed NKF, instead of the a priori model, the model constructed during the pre-flight test for a particular INS is used. To realize this, the full algorithm includes an INS error model construction algorithm, a way of reduced measurement generation, and criteria for divergence detection. INS error model construction both during pre-flight test and during flight is done by the group method of data handling (GMDH). Flight experiments were performed for an empirical study of the INS error model and its effect on the total accuracy of computed navigational data. The navigational equipment was installed on the balloon—an airborne radio-transparent object. The results of the experiments validate the effectiveness and accuracy of the proposed INS/GPS correction approach. [ABSTRACT FROM AUTHOR]

Same/different concept learning has been demonstrated in previous research in rats using matching- and non-matching-to-sample procedures with olfactory stimuli. In Experiment 1, rats were trained on the non-matching-to-sample procedure with either three-dimensional (3D plastic objects; n = 3) or olfactory (household spices, n = 5) stimuli, then tested for transfer to novel stimuli of the same, and then the alternate, modality. While all three rats trained with olfactory stimuli showed generalized non-matching to novel odors, only one rat learned the 3D relation and showed generalized transfer to novel objects. Importantly, in this rat the 3D non-matching relation then immediately transferred to odors. In contrast, rats trained with scents did not show transfer to novel 3D stimuli until after training with one or two 3D stimulus sets. In Experiment 2, four rats were trained on an incrementing non-matching-to-sample task featuring 3D plastic objects as stimuli (3D Span Task). Responses to session-novel stimuli resulted in reinforcement. Only two rats learned the 3D Span Task; one rat performed with high accuracy even with up to 17 session-novel objects in a session. While these findings emphasize the exceptional olfactory discrimination of rats relative to that with 3D/tactile/visual cues, they also show that relational learning can be demonstrated in another modality in this species. Further, the present study provides some evidence of cross-modal transfer of relational responding in rats. [ABSTRACT FROM AUTHOR]

The purpose of the current investigation was to evaluate the effect of pinch span on the perception of pinch force in typical participants. The healthy participants (10 males and 10 females) conducted an ipsilateral force reproduction test with three distinct pinch spans (2, 4, and 6 cm) at three distinct forces of 10%, 30%, and 50% maximum voluntary isometric contraction. The findings revealed a significantly greater consistency (lower variable error (VE)) of 4 cm compared with 2 and 6 cm pinch spans. Our study also showed that the participants might use a larger force (more overestimated) output for larger pinch spans (4 and 6 cm) than small pinch spans (2 cm). These results may offer significant insights into the higher rates of musculoskeletal disorders among females, enabling researchers and clinicians to design novel interventions and tools to improve pinch force perception and reduce hand injury rates in males and females. [ABSTRACT FROM AUTHOR]

This paper investigated the bending performance of post-fire lightweight polyethylene metal sandwich panels with different aspect ratios and span conditions using actual fires and post-fire three-point bending tests. The damage patterns and buckling behavior of sandwich panels after an actual fire are discussed. The effects of lamination with dimensional ratios (vertically and horizontally laminated) and span (single and double-span) on parameters, such as fire spread behavior, buckling behavior, load–deflection, bending modulus degradation efficiency, and residual bending stiffness were investigated. The results showed that the double-span fixation mode formed a double-peaked flame, becoming more evident as the aspect ratio decreased. The double-span helped suppress the upward propagation of the flame and reduced the degradation of the bending modulus. The bending stiffness was 10–20% higher than that of the single-span sandwich panels. In addition, the maximum service limit deflection of post-fire sandwich panels with different spans was also derived based on the normal limit of use standard. [ABSTRACT FROM AUTHOR]

For a simple connected graph G = (V (G),E(G)) and a positive integer k, a radio k-labelling of G is a mapping f : V (G) → { 0 , 1 , 2 , ... } such that | f (u) − f (v) | ≥ k + 1 − d (u , v) for each pair of distinct vertices u and v of G, where d(u,v) is the distance between u and v in G. The radio k-chromatic number is the minimum span of a radio k-labeling of G. In this article, we study the radio k-labelling problem for complete m-ary trees Tm,h and determine the exact value of radio k-chromatic number for these trees when k ≥ 2h − 1. [ABSTRACT FROM AUTHOR]

We perform Monte Carlo simulations to study the effect of increasing the frequency of observations and data span on the Johansen (J Econ Dyn Control 12(2–3):231–254, 1988; Likelihood-based inference in cointegrated vector autoregressive models, Oxford University Press, Oxford, 1995) maximum likelihood cointegration testing approach, as well as on the bootstrap and wild bootstrap implementations of the method developed by Cavaliere et al. (Econometrica 80(4):1721–1740, 2012; Econ Rev 33(5–6):606– 650, 2014). Considering systems with three and four variables, we find that when both the data span and the frequency vary, the power of the tests depend more on the sample length. We illustrate our findings by investigating th existence of long-run equilibrium relationships among four indicators prices of coffee. [ABSTRACT FROM AUTHOR]

We derive some inequalities involving first four central moments of discrete and continuous distributions. Bounds for the eigenvalues and spread of a matrix are obtained when all its eigenvalues are real. Likewise, we discuss bounds for the roots and span of a polynomial equation. [ABSTRACT FROM AUTHOR]

Be X t a random walk. We study its span S, i.e. the size of the domain visited up to time t. We want to know the probability that S reaches 1 for the first time, as well as the density of the span given t. Analytical results are presented, and checked against numerical simulations. We then generalize this to include drift, and one or two reflecting boundaries. We also derive the joint probability of the maximum and minimum of a process. Our results are based on the diffusion propagator with reflecting or absorbing boundaries, for which a set of useful formulas is derived. [ABSTRACT FROM AUTHOR]

Larger data sets, with more countries and a longer span of time, exhibit systematically larger effects of European monetary union on trade. I establish this stylized fact with meta-analysis and confirm it by estimating a plain-vanilla gravity model. I then explain this finding by examining systematic biases in 'multilateral resistance to trade' manifest in time-varying country fixed effects; bias grows as the sample is truncated by dropping small poor countries. [ABSTRACT FROM AUTHOR]

Anterior fusion is the gold standard procedure for unstable traumatic spinal injuries because most injuries can be managed with this atraumatic approach, which also allows good correction of kyphosis. To prevent functional deficits and degeneration of the adjacent segments, the length of fusion should be as short as possible. In recent years, a trend towards anterior fusion with cages in combination with bone substitutes can be recognized. In contrast, fusion performed with a tricortical iliac bone graft is performed less frequently because relevant donor site morbidity has to be taken into account. Additional anterior plate fixation is mandatory in cases of anterior stabilization for traumatic instability of the cervical spine. Besides anterior fusion, restoration of the sagittal profile seems to be important for the outcome following traumatic cervical spine injuries. This is due to the fact that persisting cervical kyphosis has a negative impact on the long-term results after cervical spine stabilization. [ABSTRACT FROM AUTHOR]

Every planar open Riemann surface R carries the Schiffer span $$s(\zeta )$$ and the harmonic span $$h(\zeta )$$ with respect to a point $$\zeta \in R$$ which are closely related to the conformal mappings. They induce the metrics $$s(\zeta )|d\zeta |^2$$ and $$\frac{\partial ^2 h(\zeta )}{\partial \zeta \partial \overline{\zeta }}|d\zeta |^2$$ on R, respectively. We show that both metrics in fact coincide on R, have negative curvature everywhere and are complete. For a complex parameter t in a disk B, we study the variation of the metrics on R( t). We prove that if $$\pi : {\mathcal {R}} \rightarrow B$$ is a 2-dimensional Stein manifold with $$\pi ^{-1}(t)=R(t), t\in B$$ , then $$\log s(t,\zeta )$$ and $$\log \frac{\partial ^2 h(t,\zeta )}{\partial \zeta \partial \overline{\zeta }}$$ are plurisubharmonic in $${\mathcal {R}}$$ . [ABSTRACT FROM AUTHOR]

Self-* is widely considered as a foundation for autonomic computing. The notion of autonomic systems (ASs) and self-* serves as a basis on which to build our intuition about category of ASs in general. In this paper we will specify ASs and self-* and then move on to consider some universal constructions such as products, coproducts, finite limits and colimits of ASs. All of this material is taken as an investigation of our category, the category of ASs, which we call AS. [ABSTRACT FROM AUTHOR]

The safety of submarine pipelines is largely influenced by free spans and corrosions. Previous studies on free spans caused by seabed scours are mainly based on the stable environment, where the background seabed scour is in equilibrium and the soil is homogeneous. To study the effects of background erosion on the free span development of subsea pipelines, a submarine pipeline located at the abandoned Yellow River subaqueous delta lobe was investigated with an integrated surveying system which included a Multibeam bathymetric system, a dual-frequency side-scan sonar, a high resolution sub-bottom profiler, and a Magnetic Flux Leakage (MFL) sensor. We found that seabed homogeneity has a great influence on the free span development of the pipeline. More specifically, for homogeneous background scours, the morphology of scour hole below the pipeline is quite similar to that without the background scour, whereas for inhomogeneous background scour, the nature of spanning is mainly dependent on the evolution of seabed morphology near the pipeline. Magnetic Flux Leakage (MFL) detection results also reveal the possible connection between long free spans and accelerated corrosion of the pipeline. [ABSTRACT FROM AUTHOR]

We present an algorithm for estimating the self-intersection number of closed curves on surface. Our method relies upon the knot theory, the relation between the crossing number of link in the thickened surface and the span of link in the Kauffman bracket skein module. [ABSTRACT FROM AUTHOR]

The Digit span and Corsi span tasks are frequently used to assess verbal and visuo-spatial short-term memory. Forward versions of these tasks, in which sequences of items of increasing length have to be reproduced in the order they were presented, are believed to primarily evaluate the functioning of the working memory material-specific slave systems (i.e. the phonological loop and the visuo-spatial sketchpad for verbal and visuo-spatial data, respectively). The backward versions of both tasks, in which sequences of items have to be reproduced in the reverse order, are believed to primarily tax Central Executive resources. Here, we report normative data on the forward and backward versions of the Digit span and Corsi span tasks that was collected from 362 healthy Italians ranging in age from 20 to 90 years. The results show a decremental effect of age on performance in all tasks and an ameliorative effect of education in all tasks except the Corsi span backwards. We provide correction grids for age and literacy that derive from results of the regression analyses. [ABSTRACT FROM AUTHOR]

Verbal information is coded naturally as ordered representations in working memory (WM). However, this may not be true for spatial information. Accordingly, we used memory span tasks to test the hypothesis that serial order is more readily bound to verbal than to spatial representations. Removing serial-order requirements improved performance more for spatial locations than for digits. Furthermore, serial order was freely reproduced twice as frequently for digits as for locations. When participants reordered spatial sequences, they minimized the mean distance between items. Participants also failed to detect changes in serial order more frequently for spatial than for verbal sequences. These results provide converging evidence for a dissociation in the binding of serial order to spatial versus verbal representations. There may be separable domain-specific control processes responsible for this binding. Alternatively, there may be fundamental differences in how effectively temporal information can be bound to different types of stimulus features in WM. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the effects of formulation variables on development of carvedilol (CAR) proniosomal gel formulations as potential transdermal delivery systems. Different non-ionic surfactants; polyoxyethylene alkyl ethers, namely Brij 78, Brij 92, and Brij 72; and sorbitan fatty acid esters (Span 60) were evaluated for their applicability in preparation of CAR proniosomal gels. A 2 full factorial design was employed to evaluate individual and combined effects of formulation variables, namely cholesterol content, weight of proniosomes, and amount of CAR added on performance of proniosomes. Prepared proniosomes were evaluated regarding entrapment efficiency (EE%), vesicle size, and microscopic examination. Also, CAR release through cellulose membrane and permeation through hairless mice skin were investigated. Proniosomes prepared with Brij 72 and Span 60 showed better niosome forming ability and higher EE% than those prepared with Brij 78 and Brij 92. Higher EE% was obtained by increasing both weight of proniosomes and amount of CAR added, and decreasing cholesterol content. Release rate through cellulose membrane was inversely affected by weight of proniosomes. In Span 60 proniosomes, on increasing percent of cholesterol, a decrease in release rate was observed. While in Brij 72 proniosomes, an enhancement in release rate was observed on increasing amount of CAR added. Permeation experiments showed that skin permeation was mainly affected by weight of proniosomes and that Span 60 proniosomal gels showed higher permeation enhancing effect than Brij 72. Proniosomal gel could constitute a promising approach for transdermal delivery of CAR. [ABSTRACT FROM AUTHOR]

The availability of multicore processors across a wide range of computing platforms has created a strong demand for software frameworks that can harness these resources. This paper overviews the Cilk++ programming environment, which incorporates a compiler, a runtime system, and a race-detection tool. The Cilk++ runtime system guarantees to load-balance computations effectively. To cope with legacy codes containing global variables, Cilk++ provides a “hyperobject” library which allows races on nonlocal variables to be mitigated without lock contention or substantial code restructuring. [ABSTRACT FROM AUTHOR]

The DF1-1 submarine pipeline was investigated using a dual-frequency side-scan sonar and a swath sounder system. More than a hundred scour pits under the pipeline were found, most of which have caused the span of the pipeline to increase and threatened its safety. The maximum allowable free span length (MAFSL) of the pipeline was determined through the limitations regarding maximum allowable stress under static or quasi-static loads and the onset of Vortex Induced Vibrations (VIV) under different hydrodynamic actions. The results show that the MAFSL under static conditions is 56 m. However, the MAFSLs are 30 m and 20 m under ordinary weather conditions and hurricane-induced currents for the 100-year return period, respectively, to avoid VIV as calculated by using the highest safety class factor. It is suggested that spanning pipelines longer than 20 m should be supported. Additionally, eight successive spans which may also threaten the pipeline were proposed. The most hazardous scour pits are along the pipeline section from KP42 to KP51. [ABSTRACT FROM AUTHOR]

We prove new results about the vector field problem on the real flag manifolds O(n)/O(1)xO(1)xO(n-2). For some infinite families of these manifolds, we completely solve the vector field problem. [ABSTRACT FROM AUTHOR]

A Frequency Assignment Problem (FAP) is the problem that arises when frequencies have to be assigned to a given set of transmitters so that spectrum is used efficiently and the interference between the transmitters is minimal. In this paper we see the frequency assignment problem as a generalised graph colouring problem, where transmitters are presented by vertices and interaction between two transmitters by a weighted edge. We generalise some properties of Laplacian matrices that hold for simple graphs. We investigate the use of Laplacian eigenvalues and eigenvectors as tools in the analysis of properties of a FAP and its generalised chromatic number (the so-called span). [ABSTRACT FROM AUTHOR]

One of our two main results exhibits for a vector bundle over a compact Hausdorff space X an interplay between its span, its possible splittings, and the Lyusternik-Shnirel’man category of X. The other main result, also on vector bundles and the Lyusternik-Shnirel’man category, enables us to derive certain inequalities connecting the immersion codimension, the stable span, and the Lyusternik-Shnirel’man category of a smooth closed manifold which is not stably parallelizable. Our results are applicable in various situations of general interest. [ABSTRACT FROM AUTHOR]

The setup entry is driven at the starting line of a longwall panel and used to set up equipment, from which mining activities begin. The roof stability of setup entry roof with large span is a major concern in deep underground coal mines, especially when the surrounding strata are weak and fractured. Large-span setup entry roofs at depth induce a serious danger of roof fall and difficulty in the determination of the rational span. We determined a reasonable span for such a situation by studying the 1105 large mining-height coal face setup entry of Zhaogu No. 2 coal mine. A multi-layer coupling support method, led by long-extension bolt and medium length cable, was proposed. The setup entry was designed for four layers of coupling support. The setup entry’s reasonable span was determined and the reliability of the coupling support system was analyzed. These measurements allowed us to set up separate roof depth-displacement monitors and bolt (cable)-condition sensors in the mined area and enabled us to remove secondary instrumentation. The monitoring results show that unstable setup entry roof collapse occurs as roof-fractionated instantaneous fracture within 0 to 6-10 m. The size of the hanging roof varies between 11.7 and 13.6 m at the first fracture, and the hanging roof varies between 13.0 and 14.0 m at the time of the second fracture. For complete roof instability, the reasonable span should be ~ 12.4 m. The deformation of each horizon’s roof and the roof fall achieve effective control in the anchorage range before roof fracture, and the support effect of the core level is significant with a long-extension bolt (20-mm diameter × 5000 mm) and cable (21.6-mm diameter × 12,000 mm). The roof’s rupture depth did not develop further, which indicates that the multi-layer coupling support can adapt to control the large-span roof of setup entry at depth. [ABSTRACT FROM AUTHOR]

To solve the security problem of industrial Ethernet DNP3 protocol broadcast authentication, the attack vector and security requirements of trusted DNP3 protocol are analysed. First, the paper adopts a trusted platform into the control network and authenticates the identity and security status of the DNP3 client and server to prevent node sensitive information from being compromised. Second, a trusted DNP3-BAE broadcast authentication encryption protocol is proposed based on the hash chain method to solve the problem of missing message security authentication mechanism in broadcast mode, which only needs a key to complete the broadcast message authentication for multiple slaves. The new scheme can use the DNP3-SA encryption primitive, without a major upgrade to the existing platform. The protocol is verified by the SPAN tool; the results show that there is no intrusion path, which ensures the integrity, authenticity, freshness, and confidentiality of the communication nodes. At present, there is no public document to introduce a trusted platform into the DNP3 protocol to solve security problems. Performance analysis shows that our solution reduces the overhead of large-scale broadcast authentication at the expense of increased less processing and storage overhead. [ABSTRACT FROM AUTHOR]