'Word-of-Mouse' in China: In-Depth Interviews

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Insider Threat Risk Prediction based on Bayesian Network

Insider threat protection has received increasing attention in the last ten years due to the serious con-sequences of malicious insider threats. Moreover, data leaks and the sale of mass data have become much simpler to achieve, e.g., the dark web can allow malicious insiders to divulge confidential data whilst hiding their identities. In this paper, we propose a novel approach to predict the risk of malicious insider threats prior to a breach taking place. Firstly, we propose a new framework for insider threat risk prediction, drawing on technical, organisational and human factor perspectives. Secondly, we employ a Bayesian network to model and implement the proposed framework. Furthermore, this Bayesian network-based prediction model is evaluated in a range of challenging environments. The risk level predictions for each authorised users within the organisation are examined so that any in-sider threat risk can be identified. The proposed insider threat prediction model achieved better results when compared to the empirical judgements of security experts.</p

Study on curving performance of heavy haul train under braking condition

In order to study train curving performances, 1D and 3D train dynamics models were built by numerical method. The 1D model was composed of 210 simple wagons allowed of only longitudinal motions, while the 3D train model included three complicated wagons of which longitudinal, lateral and vertical DOF could be considered. Combined with calculated results under braking condition from 1D model, behaviours of draft gear and brake shoe could be added into 3D model. The assessment of train curving performance is more focused on making a comparison between idling and braking conditions. Some results indicate as follows: When train braking is operated on a curved track, wheel-rail lateral force and derailment factor are larger than those under idling condition. Because yawing movement of wheelset is limited by brake shoe, the zone of wheel contact along wheel tread is wider than that under idling condition. Besides, as curvature gets tighter, traction ratio shows a nonlinear increasing trend, whether under idling or braking condition.With brake shoe pressure increasing, train steering gets more difficult

Exposure to greenness, air pollution and respiratory health among pre-school children in northern China

Background Evidence from developed countries on the association between greenspace and childhood respiratory health has been inconsistent whilst such evidence is largely lacking in the developing world where rapid urbanization is occurring. This study aimed to investigate the associations between surrounding greenness, air pollution and respiratory health among pre-school children in a rapidly developing city in China. Methods We recruited 2920 pre-school children in Taiyuan city. Greenness exposure was represented by the Normalized Difference Vegetation Index (NDVI) which combined estimations based on a weighted mean that children spend time both in kindergarten and home (75% home, 25% kindergarten). Air pollution exposures were estimated from a land-use-regression model which was also calculated based on a weighted mean as with greenness. Logistic regression was performed to assess the relationships between greenness, air pollution and respiratory symptoms. Results Greenness had negatively impacted respiratory health among pre-school children in Taiyuan city, particularly for current dry cough at night. A 0.1-unit increment for NDVI300m was associated with an Odds Ratio (OR) of 2.45 (95%CI: 1.33–4.53) for dry cough at night. The associations were robust after adjusting for air pollution and road condition. No statistically significant associations were found between air pollution and any symptoms. The mediating effect of air pollution on dry cough at night with greenness was not observed. Conclusion Our study found that within different buffers, a higher level of greenness was consistently associated with a higher risk of dry cough at night among pre-school children. This finding has indicated that environmental policies on urban greening should be scientifically justified to protect respiratory health among young children.</p

Co-Design Secure Control Based on Image Attack Detection and Data Compensation for Networked Visual Control Systems

The incomplete and untrue data caused by cyberattacks (e.g., image information leakage and tampering) willaffect control performance and even lead to system instability.To address this problem, a novel co-design secure control methodbased on image attack detection and data compensation fornetworked visual control systems (NVCSs) is proposed. Firstly,the existing problems of NVCSs under image attacks are an-alyzed, and a co-design secure control method including imageencryption, watermarking-based attack detection and online datacompensation is presented. Then, a detector based on double-layer detection mechanism of timeout and digital watermarkingis designed for real-time, integrity and authenticity discriminationof the image. Furthermore, according to the detection results, anonline compensation scheme based on cubic spline interpolationand post-prediction update is proposed to reduce the effect ofcumulative errors and improve control performance. Finally,the online compensation scheme is optimized by consideringthe characters of networked inverted pendulum visual controlsystems, and experimental results demonstrate the feasibility andeffectiveness of the proposed detection and control method.</p

Co-Design Secure Control Based on Image Attack Detection and Data Compensation for Networked Visual Control Systems

The incomplete and untrue data caused by cyberattacks (e.g., image information leakage and tampering) willaffect control performance and even lead to system instability.To address this problem, a novel co-design secure control methodbased on image attack detection and data compensation fornetworked visual control systems (NVCSs) is proposed. Firstly,the existing problems of NVCSs under image attacks are an-alyzed, and a co-design secure control method including imageencryption, watermarking-based attack detection and online datacompensation is presented. Then, a detector based on double-layer detection mechanism of timeout and digital watermarkingis designed for real-time, integrity and authenticity discriminationof the image. Furthermore, according to the detection results, anonline compensation scheme based on cubic spline interpolationand post-prediction update is proposed to reduce the effect ofcumulative errors and improve control performance. Finally,the online compensation scheme is optimized by consideringthe characters of networked inverted pendulum visual controlsystems, and experimental results demonstrate the feasibility andeffectiveness of the proposed detection and control method.</p

Melt Flow-Induced Mechanical Deformation and Fracture Behaviour of Dendrites in Alloy Solidification

Cellular automaton-finite volume approach and finite element method are combined to study flow-induced dendritic deformation in alloy solidification. Simulation results reveal that dendrites can undergo mechanical fracture in Al–Cu alloy solidification. The root of primary dendrite is not the location of maximum stress due to secondary dendritic bridging and uneven radius of the primary dendritic trunk. Corresponding dendrite deformation and fracture mechanisms are suggested in the paper

Explainable Multimodal Deep Dictionary Learning to Capture Developmental Differences from Three fMRI Paradigms

Objective : Multimodal-based methods show great potential for neuroscience studies by integrating complementary information. There has been less multimodal work focussed on brain developmental changes. Methods : We propose an explainable multimodal deep dictionary learning method to uncover both the commonality and specificity of different modalities, which learns the shared dictionary and the modality-specific sparse representations based on the multimodal data and their encodings of a sparse deep autoencoder. Results : By regarding three fMRI paradigms collected during two tasks and resting state as modalities, we apply the proposed method on multimodal data to identify the brain developmental differences. The results show that the proposed model can not only achieve better performance in reconstruction, but also yield age-related differences in reoccurring patterns. Specifically, both children and young adults prefer to switch among states during two tasks while staying within a particular state during rest, but the difference is that children possess more diffuse functional connectivity patterns while young adults have more focused functional connectivity patterns. Conclusion and Significance : To uncover the commonality and specificity of three fMRI paradigms to developmental differences, multimodal data and their encodings are used to train the shared dictionary and the modality-specific sparse representations. Identifying brain network differences helps to understand how the neural circuits and brain networks form and develop with age. </p

Melt flow-induced mechanical deformation of dendrites in alloy solidification: A coupled thermal fluid - solid mechanics approach

Melt flow during alloy solidification promotes more dendrite fragments or equiaxed grains due to dendrite fragmentation, while the complex interactions between melt flow and dendritic growth causing flow-induced dendrite deformation and dendrite fragmentations remain obscure. In this work, cellular automaton-finite volume approach and the displacement-based finite element method have been combined to simulate dendrite growth, fluid flow and flow-induced mechanical deformation in Al-4.5 wt%Cu alloy, and to reveal the stress evolution during dendritic growth under melt convection. It is found that dendrites can undergo visible mechanical bending under fluid flow. The stress increases with the enhancement of fluid flow. The primary dendritic trunk is the location of the dominant deformation under a parallel fluid flow. Though the secondary dendrite does not suffer the large stress, it significantly affects the stress concentration of the primary dendritic trunk. As flow velocity increases, the secondary dendrite arm spacing gradually decreases and bridging occurs due to the contact of tertiary dendrites. The bridging of secondary dendrites impedes the development of stress concentrations. Especially, as inflow velocity exceeds 0.05 m/s, the stress does not get larger than that under the velocity of 0.01 m/s under the complication interactions between the dendritic growth and flow patterns. Unlike previous understanding, the maximum stresses induced by melt flow are mainly located at the position where primary dendritic trunk intersects with unconnected secondary dendrites or the thin dendrite trunk.</p

Higher education in the Asia-Pacific: strategic responses to globalization

This survey provides unprecedented scope and detail of analysis on higher education in the Asia-Pacific region. In this era of global integration, convergence and comparison, the balance of power in worldwide higher education is shifting. In less than two decades the Asia-Pacific region has come to possess the largest and fastest growing higher education sector on Earth. The countries of East and Southeast Asia and the Western Pacific together enrol 50 million tertiary students, compared to 14 million in 1991, and will soon conduct a third of all research and development. In China, Hong Kong, Taiwan, Korea and Singapore, ‘world-class’ universities are emerging at breakneck pace, fostered by modernizing governments that see knowledge and skills as key to a future shaped equally by East and West, and supported by families deeply committed to education. But not all Asia-Pacific countries are on this path, not all reforms are effective, and there are marked differences between nations in levels of resources, educational participation, research, state controls and academic freedom. Higher Education in the Asia-Pacific: Strategic responses to globalization provides an authoritative survey of tertiary education in this diverse and dynamic region. Its 23 chapters, written by authors from a dozen different countries, focus successively on the Asia-Pacific as a whole, the strategies of individual universities, and national policies and strategies in response to the global challenge