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This paper presents a novel unsupervised learning framework for estimating scene depth and camera pose from video sequences, fundamental to many high-level tasks such as 3D reconstruction, visual navigation, and augmented reality. Although existing unsupervised methods have achieved promising results, their performance suffers in challenging scenes such as those with dynamic objects and occluded regions. As a result, multiple mask technologies and geometric consistency constraints are adopted in this research to mitigate their negative impacts. Firstly, multiple mask technologies are used to identify numerous outliers in the scene, which are excluded from the loss computation. In addition, the identified outliers are employed as a supervised signal to train a mask estimation network. The estimated mask is then utilized to preprocess the input to the pose estimation network, mitigating the potential adverse effects of challenging scenes on pose estimation. Furthermore, we propose geometric consistency constraints to reduce the sensitivity of illumination changes, which act as additional supervised signals to train the network. Experimental results on the KITTI dataset demonstrate that our proposed strategies can effectively enhance the model’s performance, outperforming other unsupervised methods.

Background Acute respiratory distress syndrome (ARDS) is a serious life threatening clinical critical illness. ARDS-related pulmonary fibrosis is a common complication of ARDS. The occurrence of early pulmonary fibrosis indicates a higher incidence and mortality of multiple organ failure. LPS-induced ARDS-related pulmonary fibrosis model in mice was established in this study. And we have explored the anti-pulmonary fibrosis effects and molecular mechanisms of the Citrus Alkaline Extracts (CAE) in vivo and in vitro. Methods Pulmonary fibrosis mouse model and lung epithelial cell injury model were established in this study. H&E, Masson and Sirius Red staining were used to estimate lung tissue damage. Immunohistochemistry and western blotting were used to analyze proteins expression. Protein-protein interaction was observed by Co-Immunoprecipitation. Systemic impact of CAE on signaling pathway was examined by RNA-seq. Results Through H&E, Masson and Sirius Red staining, it was convincingly indicated that therapeutic administration of CAE alleviated lung injury and fibrosis, while pretreated administration of CAE showed weak improvement. In vitro experiments showed that CAE had dual regulation to E-cadherin and N-cadherin, the important indicators of epithelial-mesenchymal transition (EMT). And it was further demonstrated that CAE reversed TGF-β1-induced EMT mainly through Wnt/β-catenin, Stat3/6 and COX2/PGE2 signals. Through RNA-Seq, we discovered important mechanisms by which CAE exerts its therapeutic effect. And network pharmacology analysis demonstrated core potential targets of CAE in EMT. Conclusion Thus, this study provides new therapeutic effects of CAE in anti-fibrosis, and offers potential mechanisms for CAE in LPS-induced pulmonary fibrosis. Graphical Abstract

English learning in China belongs in what is called \foreign language\" learning which has so far been little studied in the field of second language acquisition research. This study investigated within a single theoretical framework the English language development of Chinese university students as revealed from their oral production and how some learner-internal and learner-external factors contributed to this development. The oral English development was investigated by examining how the subjects used the English they learnt in the classroom to express the discourse functions of \"foreground\" and \"background\" and the concept of \"past time\" in oral narrative. The learner-internal factors considered were: the subjects' attitudes both in relation to English learning and to the classroom learning environment their motivations for learning English and their learning strategies. The learner-external factors under investigation were: the subjects' classroom learning experiences and their out-of-class contact with English. Based on some representative theories of second language acquisition and relevant empirical studies a conceptual framework was first established which delineated the possible relationships between the chosen factors and their relevant concepts. Data for the study were collected in an 11-month period from 20 students majoring in English in Foreign Languages Department of Fujian Teachers University in China. The subjects were chosen by random sampling from 98 of the 109 students enrolled in 1989. The data comprised (i) three administrations of four types of questionnaires which provided information concerning the subjects' attitudes motivations learning strategies and out-of-class contacts with English; (ii) the subjects' performance of a metalinguistic judgment test; and (iii) orthographic transcriptions of the subjects' speech elicited at an interval of three to four weeks two narratives for each subject on each of the 14 occasions. Data analyses reveal the following main findings. First discourse functions had selective impact on the subjects' choice of linguistic features to express them on their expression of the notion \"past time\" and on their adoption of self-corrections and communication strategies. Second the subjects' oral English development can be described linguistically and non-linguistically. Linguistically the development was reflected in the subjects' growing ability to use more types of linguistic features. Non-linguistically the development manifested itself in (i) an ability to break chronological order of the events described in oral narratives (ii) a growing desire to be both conceptually and linguistically accurate in oral production as indicated by the use of irregular verbs in past tense after a growing number of auxiliaries and inflectional forms of the link verb \"to be\" and by the self-correction of more types of linguistic features and (iii) a growing ability to cope with communication problems. Third the subjects' intrinsic interests in English-speaking people and in learning English appeared to be channeled by the knowledge-oriented language instruction into the adoption of the type of learning strategies which enabled them to extend only the knowledge about the target language. The lack of oral practice both in and out of the classroom resulted in a great gap between a highly analytical knowledge about the target language and an under-developed procedural knowledge. The under-developed procedural knowledge prevented the subjects from engaging in fluent oral communication. The possible dissatisfaction with their own oral learning outcomes appeared to prevent the subjects from further participating in oral practice."

A novel design of composite drilling conductor (CDC) was carried out for improving the vertical and lateral bearing capacity. Bearing characteristics of CDC was investigated when subjected to lateral and longitudinal loads based on the ultimate subgrade reaction method and pile foundation bearing theory. Theoretical models for lateral displacement and vertical load were established. Finite element analysis (FEA) was conducted, and bearing capacity and influencing factors of the composite structure were studied. Through laboratory experiments, the interaction between the structure and the soil as well as the regularity of soil deformation and stress variation in the surrounding soil were studied during installation, vertical and lateral load application. The results showed that the vertical bearing capacity increased with increasing depth of the bucket foundation under the combined effect of the composite structure. Meanwhile, the depth of the embedded point of the composite conductor increased with an increased bending moment when subjected to a combined load with a constant vertical force. When the bending moment on the structure top was constant, the lateral displacement of the structure as well as the depth of the embedded point would increase with increasing vertical force. Furthermore, the bending moment change on the top of the CDC was more significant than the vertical force regarding the lateral displacement. It is also showed that the internal bucket foundation produced an "elastic plugging" effect when the CDC was subjected to vertical loading, while soil pressure transmission occurred from the upper soil to the underlying strata soil. When subjected to lateral loads, the earth pressure on the bucket sidewall was redistributed, and the bucket foundation produced a lateral supporting effect on CDC. The composite structure effectively reduced the conductor vertical and lateral displacement and improved the lateral and vertical bearing capacity. These results provide useful theoretical references for further development and optimization of the CDC structure.

Objective: As a pharmaceutical raw material, ferric chloride hexahydrate has been included in the British Pharmacopoeia, the European Pharmacopoeia (2008) and the United States Pharmacopoeia (2015), and there are detailed discussions on quality standards and testing methods. Ferric chloride hexahydrate has not been included in the Chinese Pharmacopoeia. This study is the part of research to establish a spectrophotometric method for the determination of ferrous iron in ferric chloride hexahydrate. In this study, the two methods were discussed in detail, and the spectrophotometric method for detecting the content of ferrous iron in ferric chloride hexahydrate was proposed. Methods: The detection method on ferrous iron in ferric chloride hexahydrate among European pharmacopoeia, United States pharmacopoeia and Chemical Reagent Ferric Chloride Hexahydrate (HG/T3474-2014) of China's Chemical Industry were compared. The last two methods were not easy to operation. On the basis of the European pharmacopoeia, a method was proposed that after Fe3+ were screened with H3PO4, Fe2+ was measured by spectrophotometry, and the method was verified by experiments. Results and Conclusion: The spectrophotometry method is easy to operate and has good reproducibility. The content of ferrous iron can be calculated semi-quantitatively by masking ferric iron with H3PO4 and spectrophotometric determination of ferrous ion content. Therefore, the method established in this study can more clearly detect whether the ferrous content in ferric chloride hexahydrate is up to standard.

The electric chassis vehicle as a swing-in and swing-out unit of a 10kV centrally installed switchgear vacuum circuit breaker plays a vital role. This article introduces an electric chassis vehicle for 10kV centrally installed switchgear. This electric chassis has all the interlocking functions of the traditional chassis vehicle, and adopts high-precision ball screw, modular integral reduction motor and gear transmission, and the clutch is at the front of the beam. The bottom of the chassis is equipped with guide bearings, which are used in conjunction with special guide plates. This electric mechanism has the characteristics of high precision, low noise, smooth operation, and operation of electric and manual without manual switching, which can be directly operated. This technology can reliably improve the comprehensive technologies such as the reliability and mechanical life of electric chassis vehicle, and improve the reliability of the existing switchgear sequence control operation technology, making it possible to apply one-key sequence control operation, reducing the amount of personnel on-site operation workload and improving operation and maintenance efficiency, and reduce personal safety risks.

The complete dye-sensitized solar cell (DSC) life cycle includes three stages: “mature” period, stability period and degradation period. However, during the DSC performance adjustment period, considering the influence of both sides of the dyed-TiO2/electrolyte interface on the electron recombination process is still blank. In this paper, the effects of the environment on both sides of the interface between TiO2 and electrolyte during the DSC performance adjustment on the electron recombination process are studied. The results show that the performance adjustment of DSC is greatly influenced by the chemical environment of electrolyte. The film microstructures have a certain influence on the electron recombination process during the performance adjustment. During the performance adjustment period of DSC, the adjustment of quasi-Fermi level is more complicated under the condition of weak light than under the condition of strong light. The results of this paper are significant for studying complex systems of DSC, understanding the device working mechanism and improving the cell efficiency.

Information diffusion in social networks facilitates rapid and large-scale propagation of content. However, spontaneous diffusion behavior could also lead to the cascading of sensitive information, which is neglected in prior arts. In this paper, we present the first look into adaptive diffusion of sensitive information, which we aim to prevent from widely spreading without incurring much information loss. We undertake the investigation in networks with partially known topology, meaning that some users' ability of forwarding information is unknown. Formulating the problem into a bandit model, we propose BLAG (Bandit on Large Action set Graph), which adaptively diffuses sensitive information towards users with weak forwarding ability that is learnt from tentative transmissions and corresponding feedbacks. BLAG enjoys a low complexity of O(n), and is provably more efficient in the sense of half regret bound compared with prior learning method. Experiments on synthetic and three real datasets further demonstrate the superiority of BLAG in terms of adaptive diffusion of sensitive information over several baselines, with at least 40 percent less information loss, at least 10 times of learning efficiency given limited learning rounds and significantly postponed cascading of sensitive information.

A sandblasting-electroplating method was used to prepare the microstructure with hydrophobic properties on the surface of carbon steel. Under the optimum process parameters, a hydrophobic surface with a contact angle of 149.3°±2.5° was obtained. The results showed that, the surface composite structure constructed with the sandblasting-electroplating bonding process has excellent hydrophobic properties.

Influence Maximization (IM) aims to maximize the number of people that become aware of a product by finding the `best' set of `seed' users to initiate the product advertisement. Unlike prior arts on static social networks containing fixed number of users, we undertake the first study of IM in more realistic evolving networks with temporally growing topology. The task of evolving IM ({\bfseries EIM}), however, is far more challenging over static cases in the sense that seed selection should consider its impact on future users and the probabilities that users influence one another also evolve over time. We address the challenges through $\mathbb{EIM}$, a newly proposed bandit-based framework that alternates between seed nodes selection and knowledge (i.e., nodes' growing speed and evolving influences) learning during network evolution. Remarkably, $\mathbb{EIM}$ involves three novel components to handle the uncertainties brought by evolution

To realize a broadened band gap as a potential application of vibration control in the electric vehicle powertrain system requires, a novel configuration of locally resonant (LR) beam with multi-oscillators attached is proposed, in which two types of oscillators are periodically and alternately attached at identical intervals. An analytical model is proposed based on transfer matrix method, which is validated by a finite element simulation. The band gaps in flexural vibration generated by this novel structure are investigated by the analytical model. The band gap coupling effect is observed and the influence of the intervals and oscillator parameters are discussed. The novel configuration effectively enlarges the range of band gaps in flexural vibrations.

Presented in this paper is a multi-scale analysis for environmental dispersion in a three-layer wetland for predicting the critical length of contaminant cloud that derives from instantaneous emission. The analysis of dependence of the dispersivity on characteristic parameters is determined. Longitudinal concentration distribution centered at the origin of a moving coordinate system is characterized to illustrate the effects of dimensionless parameters on the environmental dispersion. For the heavy metal Hg that is emitted as pollutant, an application is carried out to predict the critical length of the contaminant cloud beyond given environmental standard level, with comparisons of results between the cases of different apparent reaction rates. The work provides two valuable indicators, namely critical length and duration, for the wetlands restoration.

A low-cost, microfluidic fluorescence-activated cell sorting (μFACS) microchip integrated with two piezoelectric lead–zirconate–titanate actuators was demonstrated for automated, high-performance mammalian cell analysis and enrichment. In this PDMS–glass device, cells were hydrodynamically focused into a single file line in the lateral direction by two sheath flows, and then interrogated with a forward scattering and confocal fluorescent detection system. The selected cells were displaced transversely into a collection channel by two piezoelectric actuators that worked in a pull–push relay manner with a minimal switching time of ~0.8 ms. High detection throughput (~2500 cells/s), high sorting rate (~1250 cells/s), and high sorting efficiency (~98%) were successfully achieved on the μFACS system. Six cell mixture samples containing 22.87% of GFP-expressing HeLa cells were consecutively analyzed and sorted on the chip, revealing a stable sorting efficiency of 97.7 ± 0.93%. In addition, cell mixtures containing 37.65 and 3.36% GFP HeLa cells were effectively enriched up to 83.82 and 78.51%, respectively, on the microchip, and an enrichment factor of 105 for the low-purity (3.36%) sample was successfully obtained. This fully enclosed, disposable microfluidic chip provides an automated platform for low-cost fluorescence-based cell detection and enrichment, and is attractive to applications where cross-contamination between runs and aerosol hazard are the primary concerns.

Chlorophyll-a concentration of Huguangyan Maar Lake sediments were determined by diffuse reflectance spectroscopy.Through comparison with TOC,Sr intensity and magnetic susceptibility we concluded that chlorophyll-a can be taken as a reliable proxy of primary production,higher chlorophyll-a absorption reflects stronger monsoon intensity and higher precipitation,and vice versa.Holocene environment evolution at Zhanjiang area reconstructed by chlorophyll-a,TOC,Sr intensity and magnetic susceptibility of Huguangyan Maar Lake sediments demonstrated that the monsoon intensity in Zhanjiang area was strong in the early Holocene and declined dramatically since 6000 a BP.Holocene climate evolutional pattern at Zhanjiang area is similar with many other records from the monsoonal areas of the North hemisphere and summer isolation at 30°N,implying that solar isolation is the driving force of millennial-scale Holocene monsoon evolution at Zhanjiang area.However,monsoonal evolution lags behind solar isolation by about 2200 a.Monsoon strengthen demonstrated by chlorophyll-a declined significantly since 6000 a BP.Nonetheless,all the other records display gradual weakening process.Negative feedback of vegetation-atmosphere induced by solar isolation might have caused quick droughty trend,on the other hand,dilution effect led by increased sedimentary rate may amplify declining trend of chlorophyll-a around 6000 a BP.Sedimentary environment since 3600 a BP could be impacted by human activities.

En utilisant des etudiants en interpretation comme sujets, cet article traite d'une variable de la realisation des tâches: la planification. Il examine la question de la maniere dont les possibilites de planifier une tâche affectent les performances sur le plan de la precision grammaticale de l'interpretation orale dans la seconde langue. Les resultats revelent que: 1. la planification prealable aux tâches n'affecte pas de maniere significative l'utilisation des formes du temps passe dans leur ensemble; 2. la planification en ligne ne conduit pas necessairement a une amelioration de la production des formes du temps passe analogues a la langue cible. Dans le cas d'une planification en ligne, une observation interessante est le fait qu'un nombre considerablement plus grand de formes transitionnelles non analogues a la langue cible est produit, ce qui demontre la variabilite inherente de la grammaire de developpement de la seconde langue; 3. des manipulations externes telles que la planification ne semblent pas contribuer enormement a retrouver des formes grammaticales analogues a la langue cible. Cette etude remet en question l'impact de la planification en ligne, etant donne que des formes interlangagieres plus nombreuses, ainsi que des formes analogues a la langue cible, sont stockees simultanement dans le lexique mental des utilisateurs de la seconde langue. Cette etude ne cherche pas a formuler un jugement definitif a propos de la strategie la plus efficace pour eliminer un manque de precision, mais elle semble indiquer que l'idee repandue selon laquelle la planification (prealable aux tâches ou en ligne) ameliorerait la precision, doit etre consideree avec prudence, en particulier dans le cadre des etudes d'interpretation.

OBJECTIVE: To investigate the effect of monophosphoryl lipid A (MLA) on ischemia/reperfusion (I/R) injury in rabbit heart and its signal transduction pathway. METHODS: Eighteen rabbits were randomly assigned to three groups: (1) MLA-group: Six rabbits received injection of MLA (35mgr;g/kg, iv) 24 h prior to 45 min of ischemia followed by 60 min of reperfusion. (2) Control group: Six rabbits received an intravenous bolus injection of the same volume of vehicle. (3) SB group: Six rabbits intravenously received 2mgr;mol/l SB 203580 30-min prior to MLA administration. At the end of reperfusion, myocardial infarct size and serum nitrite/nitrate were detected. Myocardium p38 mitogen-activated protein kinase (p38 MAPK) was detected using a Western blotting method. RESULTS: MLA pretreatment caused a significant reduction of infarct size as percent of area at risk as compared to vehicle-pretreated controls (36+/-3 vs. 65+/-4%, P0.001). Total nitrite in serum increased in MLA pretreated animals (P0.05). The protective effects of MLA were completely abolished by selective p38 MAPK inhibitor SB 203580. Western blot analysis showed significant accumulations of p38 MAPK proteins in the myocardium of MLA pretreated animals. CONCLUSIONS: MLA can protect the heart by reducing myocardial infarct size in rabbits. This cardioprotective effect might be attributed to upregulation of nitric oxide (NO) through the activation of p38 MAPK.

Sports economics is a new discipline. It has developed in our country for only over a decade. The discussion about its basic concept has never been stopped. Its primary task is to get to understand the disciplinary attributes, characteristics and scope of this discipline. This paper tries to clarify its disciplinary attributes, highlights its disciplinary characteristics and defines its research scope, combined with the research results of relevant scholars and related disciplines.

Considering the influence of tire pressure on tire stiffness, a dynamic model of the polygonal wear of tire was established based on the lateral vibration of tire tread, and the dynamical behavior of system was analyzed through numerical simulation. The results show that: the polygonal wear is a typical nonlinear self-excitation vibration phenomenon which is proved to be a kind of stable periodic vibration caused by Hopf bifurcation of system; when tire pressure is inadequate or excessive may lead to polygonal wear of tire.

Using advanced simulation techniques in evaluating civil airplane’s airport compatibility can make the analysis procedure visualized and efficiently integrating human factors. This paper presents a virtual reality based paradigm for evaluating civil airplane’s airport compatibility. The research focuses on two points of civil airplane’s airport compatibility’s simulation: 1) Simulation and evaluation of ground handling process. 2) Simulation of human factors involved in ground handling. To achieve the objectives above, a prototype software system, called Airport Compatibility Rapid Analysis System (ACRAS), has been developed. Design and development aspects of ACRAS are discussed in this paper and a test case is presented to demonstrate the usability and effectiveness of the paradigm. IRCRAFT design is an information intensive engineering process which is full of evaluation and decisionmaking 1 . Conceptual design and preliminary design phases consume relatively less time and costs compared to the entire design process, but a lot of important decisions will be made during these two periods. It is estimated that as much as 80% of the life cycle costs of an aircraft is decided in the conceptual design and preliminary design phase 2 . A lot factors should be considered in early stage. For a civil airplane, airport compatibility is one of the most important design factors in design process which must be considered in early design stage. If an airplane has good airport compatibility, it means most airports can be compatible with the airplane smoothly without any special transformation. It can reduce the costs and improve the airplane’s economy. Otherwise, it means more costs, more risks and greater possibility of failure. In other words, the airport compatibility of an airplane has a direct impact on its market competitiveness. Civil airplane’s airport compatibility contains many aspects 3

With the increasing prevalence of virtualization and cloud technologies, virtual security appliances have emerged and become a new way for traditional security appliances to be rapidly distributed and deployed in IT infrastructure. However, virtual security appliances are challenged with achieving optimal performance, as the physical resource is shared by several virtual machines, and this issue is aggravated when virtualizing network intrusion detection systems (NIDS). In this paper, we proposed a novel approach named fuzzyVIDS, which enables dynamic resource provision for NIDS virtual appliance. In fuzzyVIDS, we use fuzzy model to characterize the complex relationship between performance and resource demands and we develop an online fuzzy controller to adaptively control the resource allocation for NIDS under varying network traffic. Our approach has been successfully implemented in the iVIC platform. Finally, we evaluate our approach by comprehensive experiments based on Xen hypervisor and Snort NIDS and the results show that the proposed fuzzy control system can precisely allocate resources for NIDS according to its resource demands, while still satisfying the performance requirements of NIDS.

This work explains the hopf bifurcation and stability of self-excited vibration with the variety of vehicle velocity. Polygonal wear of tire is one of the most pressing problems to be solved in the process of a vehicle's research and design. Based on the non-linear character of friction coefficient, which combines the concept of static and kinetic friction, a model of tread-pavement, taking time-delay into account, is built. The phenomenon of hard self-excited and hopf bifurcation is proved after simulating in matlab.

The intention behind this work is to develop a friction coefficient model understanding of self-excited vibrations. As a result of self-oscillation, Polygonal Wear often occurred on the tire of truck/bus and car which run on freeways or highways continuously. Based on the characters of Polygonal Wear, we showed a mass-on-moving-belt frictional vibration model, which reflected the phenomenon of lateral vibration caused by velocity and deflection angle. When Coulombpsilas friction law couldn't explain the energy transferring and converting between the frictional vibration system, we built a new friction coefficient model by comparing to other frictional vibration models, then we put the whole system into simulation within this model, that was proved out reasonably and showed the influence of model parameters concerned.