Vertex centrality of complex networks based on joint nonnegative matrix factorization and graph embedding

Finding crucial vertices is a key problem for improving the reliability and ensuring the effective operation of networks,solved by approaches based on multiple attribute decision that suffer from ignoring the correlation among each attribute or the heterogeneity between attribute and structure. To overcome these problems, a novel vertex centrality approach, called VCJG, is proposed based on joint nonnegative matrix factorization and graph embedding. The potential attributes with linearly independent and the structure information are captured automatically in light of nonnegative matrix factorization for factorizing the weighted adjacent matrix and the structure matrix, which is generated by graph embedding. And the smoothness strategy is applied to eliminate the heterogeneity between attributes and structure by joint nonnegative matrix factorization. Then VCJG integrates the above steps to formulate an overall objective function, and obtain the ultimately potential attributes fused the structure information of network through optimizing the objective function. Finally, the attributes are combined with neighborhood rules to evaluate vertex's importance. Through comparative analyses with experiments on nine real-world networks, we demonstrate that the proposed approach outperforms nine state-of-the-art algorithms for identification of vital vertices with respect to correlation, monotonicity and accuracy of top-10 vertices ranking.

Image Fusion Based on Complex Contourlet Transform and Nonnegative Matrix Factorization

An image fusion method combining complex contourlet transform(CCT) with nonnegative matrix factorization(NMF) is proposed in this paper.After two images are decomposed by CCT,NMF is applied to their highand low-frequency components,respectively,and finally an image is synthesized.Subjective-visual-quality of the image fusion result is compared with those of the image fusion methods based on NMF and the combination of wavelet /contourlet /nonsubsampled contourlet with NMF.The experimental results are evaluated quantitatively,and the running time is also contrasted.It is shown that the proposed image fusion method can gain larger information entropy,standard deviation and mean gradient,which means that it can better integrate featured information from all source images,avoid background noise and promote space clearness in the fusion image effectively.

State Estimation Method for GNSS/INS/Visual Multi-sensor Fusion Based on Factor Graph Optimization for Unmanned System

With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss.

Application of fluid modulus inversion to complex lithology reservoirs in deep-water areas

It has been a challenge to distinguish between seismic anomalies caused by complex lithology and hydrocarbon reservoirs using conventional fluid identification techniques,leading to difficulties in accurately predicting hydrocarbon-bearing properties and determining oil-water contacts in reservoirs.In this study,we built a petrophysical model tailored to the deep-water area of the Baiyun Sag in the eastern South China Sea based on seismic data and explored the feasibility of the tri-parameter direct inversion method in the fluid identification of complex lithology reservoirs,offering a more precise alternative to conventional techniques.Our research found that the fluid modulus can successfully eliminate seismic amplitude anomalies caused by lithological variations.Furthermore,the seismic databased direct inversion for fluid modulus can remove the cumulative errors caused by indirect inversion and the influence of porosity.We discovered that traditional methods using seismic amplitude anomalies were ineffective in detecting fluids,determining gas-water contacts,or delineating high-quality reservoirs.However,the fluid factor Kf,derived from solid-liquid decoupling,proved to be sensitive to the identification of hydrocarbon-bearing properties,distinguishing between high-quality and poor-quality gas zones.Our findings confirm the value of the fluid modulus in fluid identification and demonstrate that the tri-parameter direct inversion method can significantly enhance hydrocarbon exploration in deep-water areas,reducing associated risks.

Equivalent circuit with complex physical constants and equivalent-parameters-expressed dissipation factors of piezoelectric materials

The equivalent circuit with complex physical constants for a piezoelectric ceramic in thickness mode is established. In the equivalent circuit, electric components （equivalent circuit parameters） are connected to real and imaginary parts of complex physical coefficients of piezoelectric materials. Based on definitions of dissipation factors, three of them （dielectric, elastic and piezoelectric dissipation factors） are represented by equivalent circuit parameters. Since the equivalent circuit parameters are detectable, the dissipation factors can be easily obtained. In the experiments, the temperature and the stress responses of the three dissipation factors are measured.

Compact implicit integration factor methods for some complex-valued nonlinear equations

The compact implicit integration factor （cIIF） method is an efficient time discretization scheme for stiff nonlinear diffusion equations in two and three spatial dimensions. In the current work, we apply the cIIF method to some complex-valued nonlinear evolutionary equations such as the nonlinear SchrSdinger （NLS） equation and the complex Ginzburg-Landau （GL） equation. Detailed algorithm formulation and practical implementation of cIIF method are performed. The numerical results indicate that this method is very accurate and efficient.

Mammalian target of rapamycin complex 1 as an inducer of neurotrophic factors in dopaminergic neurons

The defining neuropathological feature of Parkinson＇s disease （PD） is the loss of nigrostriatal dopaminergic （DA） projections. This results in striatal dopamine levels and a biochemical reduction of movement disorders, such as a tremor at rest, rigidity of the limbs, bradykinesia, and postural instability （Kim et al., 2011; Kim et al., 2012; Burke and O＇Malley, 2013; Leem et al., 2014; Namet al., 2014）.

Analysis of the stress intensity factor of welded joints under prior corrosion and complex stress fields

Taking cruciform welded joints under different corrosion degrees, together with 45° inclined angle and full penetration load-carrying fillet, as the research object, the stress intensity factor of a quarter-circular comer crack of welded joints is calculated based on FRANC3D with ABAQUS. Effects of different corrosion pit sizes, crack aspect ratios, and crack depths on stress intensity factor are analyzed. The results show that pit depth plays a major role in stress intensity factor, while the effect of pit radius is relatively small. The cracking modes of the surface and the deepest point are mode I, and mixed modes I and II, respectively. Effects of pit depths, crack aspect ratios, and crack depths on the stress intensity factor at the surface point are greater than at the deepest point.

Frequency and Risk Factors of Complex Regional Pain Syndrome in Cotonou (Benin)

Aim: To determine the frequency and the risk factors of Complex Regional Pain syndrome (CRPS) in Cotonou (Benin). Patients and Méthod: This has been a transversal study carried out over 22 years on files of CRPS infected patients and submitted to rheumatologic consultation in the National Hospital University of Cotonou. Results: 73 out of 17,342 patients examined (0.42%) were suffering from CRPS. Those 73 patients (40 women, 54.8% and 33 men, 45.2%) were in average 54.66 years old and enjoyed an average duration of evolution of 5.79 months. The trauma (41 cases, 56.1%), the stroke (19 cases, 25%), the diabetes (8 cases, 11.3), were the main risk factors that were observed. CRPS was preferably located at the shoulder-hand (34.2%), shoulder (28.8%), wrist-hand (16.4%) and knee (11%). Inflammatory pain was observed in 55 cases. The treatment was dominated by griseofulvina (41 cases, 56.1%), antiinflammatory drugs (38 cases, 52%), analgesic (20 cases, 27, 3%), joint injection by betamethasone (17 cases, 27%). Conclusion: CRPS is not rare in our country. The first risk factor remains the trauma in rheumatologic consultation in Cotonou.

Modified projective synchronization with complex scaling factors of uncertain real chaos and complex chaos

To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors （CMPS） of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes.

Predictive Meteorological Factors for Elevated PM2.5 Levels at an Air Monitoring Station Near a Petrochemical Complex in Yunlin County, Taiwan

Since 1991, air pollution has gained special attention in Taiwan after a petrochemical complex was constructed in Mailiao Township, Yunlin County. We explored the association between the magnitude of PM2.5 and meteorological factors during 2012-2016. Our findings revealed that 1) mean PM2.5 levels gradually decreased from 30.70 μg/m3 in 2013 to 25.36 μg/m3 in 2016;2) wind speed is the main determinant of air quality—air quality significantly improved when it was faster than 4 m/sec;and 3) wind direction is another determinant of air quality—when the wind direction was southerly, air quality improved. Elevated PM2.5 levels were defined as those hourly levels higher than the third quartile (36 μg/m3). The significantly negative predictive factors for elevated PM2.5 levels were the summer or autumn seasons, rainfall, increased wind speed, and wind direction from 150&#176 to 230&#176 from the north. The significantly positive predictive factors for elevated PM2.5 levels were working hours from 6 a.m. to 2 p.m., a temperature between 11&#176C and 25&#176C, relative humidity between 40% and 68%, and wind direction (e.g., northerly wind, northeasterly wind, and easterly wind). The predictive formula is attached in the Appendix. Therefore, people should protect themselves on these high-risk days.

SPECTRAL VARIATION AND CHARACTERISTICS OF LOW VALENCY RARE EARTH IONS IN COMPLEX OXIDESⅢ.EFFECT OF THE CRYSTAL ENVIRONMENT AND CHEMICAL FACTORS ON LUMINESCENCE PROPERTIES OF EUROPIUM (Ⅱ) ION

In this paper,the influence of crystal-field on the Luminescence properties of Eu^(2+) in complex oxides are studied theoretically by using purely electrostatic model,the dependence of the 4f^65d levels on Eu-O bond distance is given.Quantum chemistry calculation shows that the splitting extent of 4f^65d energy band in cubic or in octahedral fields will be inversely proportional to R^5,where R is the distance of Eu^(2+) to oxygen ligand.The value of R affects slightly the location of the centre of 4f^65d energy band.According to the exper- imental spectrum data,we have discussed the influence of the host chemical composition,the replaced sites of Eu^(2+) and degree of covalency of Eu-O bond on luminescence properties of Eu^(2+).Some regularity of fluorescence spectrum was observed. In alkali-alkaline earth-phosphates,the splitting extent of 4f^65d band (△E) becomes smaller as the Eu-O bond distance (R) increases.In Na_(3-x)(PO_4)_(1-x)(SO_4)_x and Na_(2-x)CaSi_(1-x)P_xO_4 hosts,d-d emission peak of Eu^(2+) will shift to shorter wavelength with the increase of x's value. The crystal structure data show that Eu^(2+) in K_2Mg_2(SO_4)_3 is affected more strongly by crystal-field and covalancy than in KMgF_3,so K_2Mg_2(SO_4)_3:Eu^(2+) emits blue light (E_(em)~m=400nm) and KMgF_3:Eu^(2+) produces ultraviolet fluorescence.

Human Factors While Using Head-Up-Display in Low Visibility Flying Conditions

Flying an aircraft in low visibility is still a challenging task for the pilot.It requires precise and accurate situational awareness(SA)in real-time.A Head-up Display(HUD)is used to project collimated internal and externalflight information on a transparent screen in the pilot’s forwardfield of view,which eliminates the change of eye position between Head-Down-Display(HDD)instru-ments and outer view through the windshield.Implementation of HUD increases the SA and reduces the workload for the pilot.But to provide a betterflying capability for the pilot,projecting extensive information on HUD causes human factor issues that reduce pilot performance and lead to accidents in low visibility conditions.The literature shows that human error is the leading cause of more than 70%of aviation accidents.In this study,the ability of the pilot able to read background and symbology information of HUD at a different level of back-ground seen complexity,such as symbology brightness,transition time,amount of Symbology,size etc.,in low visibility conditions is discussed.The result shows that increased complexity on the HUD causes more detection errors.

Fasting produces antidepressant-like effects via activating mammalian target of rapamycin complex 1 signaling pathway in ovariectomized mice

Recent studies have shown that a 9-hour fast in mice reduces the amount of time spent immobile in the forced swimming test.Howeve r,whether 9-hour fasting has therapeutic effects in female mice with depressive symptoms has not been established.Therefore,in this study,we simulated perimenopausal depression via an ovariectomy in mice,and subjected them to a single 9-hour fasting 7 days later.We found that the ovariectomy increased the time spent immobile in the forced swimming test,inhibited expression of the mammalian target of rapamycin complex 1 signaling pathway in the hippocampus and prefro ntal cortex,and decreased the density of dendritic spines in the hippocampus.The 9-hour acute fasting alleviated the above-mentioned phenomena.Furthermore,all of the antidepressant-like effects of 9-hour fasting were reve rsed by an inhibitor of the mammalian to rget of rapamycin complex 1.Electrophysiology data showed a remarkable increase in long-term potentiation in the hippocampal CA1 of the ovariectomized mice subjected to fasting compared with the findings in the ovariectomized mice not subjected to fasting.These findings show that the antidepressant-like effects of 9-hour fasting may be related to the activation of the mammalian target of the rapamycin complex 1 signaling pathway and synaptic plasticity in the mammalian hippocampus.Thus,fasting may be a potential treatment for depression.

Role of brahma-related gene 1/brahma-associated factor subunits in neural stem/progenitor cells and related neural developmental disorders

Different fates of neural stem/progenitor cells(NSPCs)and their progeny are determined by the gene regulatory network,where a chromatin-remodeling complex affects synergy with other regulators.Here,we review recent research progress indicating that the BRG1/BRM-associated factor(BAF)complex plays an important role in NSPCs during neural development and neural developmental disorders.Several studies based on animal models have shown that mutations in the BAF complex may cause abnormal neural differentiation,which can also lead to various diseases in humans.We discussed BAF complex subunits and their main characteristics in NSPCs.With advances in studies of human pluripotent stem cells and the feasibility of driving their differentiation into NSPCs,we can now investigate the role of the BAF complex in regulating the balance between self-renewal and differentiation of NSPCs.Considering recent progress in these research areas,we suggest that three approaches should be used in investigations in the near future.Sequencing of whole human exome and genome-wide association studies suggest that mutations in the subunits of the BAF complex are related to neurodevelopmental disorders.More insight into the mechanism of BAF complex regulation in NSPCs during neural cell fate decisions and neurodevelopment may help in exploiting new methods for clinical applications.

复杂载荷、极端环境下焊接结构疲劳寿命预测研究综述

焊接接头易出现缺陷和应力集中,在疲劳载荷作用下将成为疲劳裂纹萌生和扩展的薄弱区域。与均质材料相比,接头各区域微观组织及应力局部化使得焊接结构疲劳问题进一步复杂化。区别于理想实验条件,实际焊接结构服役环境复杂,疲劳寿命预测须考虑环境因素与焊接结构耦合特性。为此,对影响焊接结构的内在因素进行总结分析,从复杂载荷和极端服役环境两方面对现有焊接结构寿命预测模型进行综述,结合最新研究进展对改进焊接结构疲劳寿命评估方法提出建议。

旅游交通综合体影响因素及动力机制研究

旅游交通综合体属于交通运输与旅游业融合发展进程中的新生事物。为有效推进旅游交通综合体健康、可持续发展,针对目前其概念内涵不清晰、影响因素不明确、发展路径不明朗、建设发展偏盲目等问题,基于节点布局规律,借助交通运输学、旅游学、经济学、系统学等相关理论,提出旅游交通综合体的定义、内涵、主要组成要素及构成原理。借鉴旅游目的地生命周期理论,提出了旅游交通综合体“孕育阶段—快速成长阶段—逐步成熟阶段—稳定阶段—衰退(或重生)阶段”的演进发展过程。遵循“研究基础—理论体系—影响因素—阶段分析—动力机制”的总体思路,从文献分析、实证探索、自身功能特征分析3方面入手,通过专家问卷调查确定旅游交通综合体的2个1级影响因素、12个2级影响因素和37个3级影响因素。依据主成分分析法,遴选确定7个核心影响因素。利用动力机制中“内生动力、外生动力”等相关概念和作用原理,对旅游交通综合体的影响机理和动力机制进行分析。在此基础上,深入剖析5个发展阶段的核心影响因素和辅助影响因素,进而得出旅游交通综合体不同阶段发展演进的影响机理及推动其发展演进的核心动力因素。

浓缩生长因子在复杂牙拔除后牙槽窝处理中的应用

目的观察浓缩生长因子(CGF)在复杂牙拔除后牙槽窝处理中的应用效果。方法90例接受复杂牙拔除的患者随机分为两组,观察组采用CGF处理牙槽窝,对照组采用牙槽窝常规处理,比较两组的牙槽嵴宽度和高度、牙槽嵴骨量。结果术后30 d、90 d,观察组的牙槽嵴宽度、高度均高于同期对照组(P<0.05)。术后90 d,两组的REC均升高,且观察组的REC高于对照组(P<0.05)。结论CGF用于复杂牙拔除后牙槽窝的处理可有效维持牙槽嵴的高度及宽度,防止拔牙后牙槽骨吸收。

速调管放大器输入腔的匹配理论和模拟研究

基于输入微波与腔体耦合的等效电路模型,对于任意的腔体和电子束参数,建立了任意的输入微波与腔体耦合的速调管放大器输入腔的两种匹配状态的理论。建立了带有互感和电子束等效电阻和电容等参数的输入腔等效电路模型,推导了入射功率与反射功率的表达式,以及输入微波与带有电子束的输入腔耦合的完全匹配状态和任意的耦合这两种情形时输入功率和间隙电压关系的公式。推导了完全匹配状态时输入微波工作频率与输入腔有载品质因数的表达式。推导了复耦合系数等于1时输入腔外观品质因数与热腔品质因数的表达式,得出了当工作频率等于输入腔谐振频率,输入腔外观品质因数与热腔品质因数相等,且满足电子束等效电容远小于1时接近达到匹配状态,与传统理论基本一致。通过对比两种状态时的入射功率,得出了匹配状态时的入射功率小于复耦合系数等于1时入射功率的结论。通过对比复耦合系数等于1时新理论和传统理论的入射功率,得出不考虑电子束等效电容情况下两者相等的结论。采用二维粒子模拟的模型与匹配理论进行了对比,粒子模拟与理论基本一致。根据匹配理论找到了接近匹配状态的工作频率与有载品质因数以及较小的输入功率。