Due to its significant applications in many relevant fields, light detection in the solar‐blind deep‐ultraviolet (DUV) wavelength region is a subject of great interest for both scientific and ...industrial communities. The rapid advances in preparing high‐quality ultrawide‐bandgap (UWBG) semiconductors have enabled the realization of various high‐performance DUV photodetectors (DUVPDs) with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional DUV detectors. This article presents a comprehensive review of the applications of inorganic UWBG semiconductors for solar‐blind DUV light detection in the past several decades. Different kinds of DUVPDs, which are based on varied UWBG semiconductors including Ga2O3, MgxZn1−xO, III‐nitride compounds (AlxGa1−xN/AlN and BN), diamond, etc., and operate on different working principles, are introduced and discussed systematically. Some emerging techniques to optimize device performance are addressed as well. Finally, the existing techniques are summarized and future challenges are proposed in order to shed light on development in this critical research field.
Recent advances in developing solar‐blind deep ultraviolet light (DUV) photodetectors based on various inorganic ultrawide‐bandgap semiconductors are reviewed, such as Ga2O3, MgxZn1−xO, III‐nitride compounds (AlxGa1−xN/AlN and BN), and diamonds.
Previous research on the 'dark side' of high-performance work systems (HPWS) has generally recognized HPWS as a job demand and suggested that it induces a series of health problems to employees. ...However, so far, less attention has been paid to the remedies that alleviate this negative effect. In this study, we investigate whether and how employees' personal and job resources help them refrain from health impairment due to service-oriented HPWS (SHPWS) in the healthcare service setting. Specifically, drawing on the job demands-resources model, we propose that core self-evaluations (CSE) and servant leadership (SL), representing personal and job resources, respectively, could buffer the health-impairment process of SHPWS due to strain. The results of a two-wave study of 223 healthcare employees in China generally support our hypotheses. For employees with a lower CSE or with leaders who demonstrate less SL, SHPWS increases their strain, which ultimately leads to mental and physical health problems. In contrast, for employees with a higher CSE or with leaders who demonstrate higher SL, the impact of SHPWS on strain and health is nonsignificant. We find no three-way interaction of SHPWS, CSE and SL on employees' strain or health.
Individualism and stock price crash risk An, Zhe; Chen, Zhian; Li, Donghui ...
Journal of international business studies,
12/2018, Letnik:
49, Številka:
9
Journal Article
Recenzirano
Employing a sample of 26,473 firms across 42 countries from 1990 to 2013, we find that firms located in countries with higher individualism have higher stock price crash risk. Furthermore, ...individualism can be transmitted by foreign investors from overseas markets to influence local firms’ crash risk, and can exacerbate the impact of firm risk taking and earnings management on crash risk. Moreover, the positive relation between individualism and crash risk is amplified during the global financial crisis and attenuated by enhanced country-level financial information transparency and the adoption of International Financial Reporting Standards.
Substrate‐supported metal–organic frameworks (MOFs) films are desired to realize their potential in practical applications. Herein, a novel substrate‐seeding secondary‐growth strategy is developed to ...prepare composites of uniform MOFs films on aerogel walls. Briefly, the organic ligand is “pre‐seeded” onto the aerogel walls, and then a small amount of metal‐ion solution is sprayed onto the prepared aerogel. The sprayed solution diffuses along the aerogel walls to form a continuous thin layer, which confines the nucleation reaction, promoting the formation of uniform MOFs films on the aerogel walls. The whole process is simple in operation, highly efficient, and eco‐friendly. The resulting hierarchical MOFs/aerogel composites have abundant accessible active sites and enable excellent mass transfer, which endows the composite with outstanding catalytic activity and stability in both liquid‐phase CO2 cycloaddition and electrochemical oxygen evolution reaction (OER) process.
Metal–organic framework (MOF) thin films are coated onto the walls of aerogel giving MOFs/aerogel composites. These have abundant accessible active sites and excellent mass transfer ability, and thus a relatively high catalytic activity and stability in the CO2 cycloaddition and oxygen evolution reaction (OER).
AbstractEmerging trends of resilient and reliable water infrastructure advocate for the development of efficient state estimation (SE) techniques in water distribution systems (WDSs). SE refers to ...estimating the flows and heads in the WDS at unmonitored locations based on measurements collected from limited monitoring locations. Current physics-based SE methods typically require more exhaustive than readily available information about the WDS and are computationally demanding to attain real-time SE fully. Using neural networks for SE is a promising avenue because neural networks are more adaptable to the availability of sensory data and can shift most of the computation efforts to the offline training phase. Once trained, the inference is more computationally efficient compared to the physics-based SE methods. This work proposes a graph neural network (GNN) model for SE in WDSs. Unlike traditional neural networks, GNNs are more suitable for the SE problem for two main reasons: (1) given a limited number of monitoring locations, the SE problem inherently requires a semisupervised learning method, and (2) GNNs enable learning from the graph structure of a WDS, thus providing a mechanism to incorporate the functional relationships between the monitored and unmonitored locations and incorporate the physical laws during the training process. To evaluate the performance of GNNs for SE, we tested supervised and semisupervised approaches, investigated the impact of GNN architecture choices on its performance, and examined model performance under different levels of noise in the training data. The results demonstrate that GNNs are promising for SE for their ability to learn from graph structure with a limited amount of information while exhibiting robustness to noise. This study contributes toward advancing real-time GNN-based SE in WDSs. Future research is needed to incorporate various hydraulic devices and investigate the scalability of GNNs to large-scale WDSs.
This paper addresses the impact of the structure of the viral propagation network on the viral prevalence. For that purpose, a new epidemic model of computer virus, known as the node-based SLBS ...model, is proposed. Our analysis shows that the maximum eigenvalue of the underlying network is a key factor determining the viral prevalence. Specifically, the value range of the maximum eigenvalue is partitioned into three subintervals: viruses tend to extinction very quickly or approach extinction or persist depending on into which subinterval the maximum eigenvalue of the propagation network falls. Consequently, computer virus can be contained by adjusting the propagation network so that its maximum eigenvalue falls into the desired subinterval.
False data injection attacks (FDIAs) on sensor networks involve injecting deceptive or malicious data into the sensor readings that cause decision-makers to make incorrect decisions, leading to ...serious consequences. With the ever-increasing volume of data in large-scale sensor networks, detecting FDIAs in large-scale sensor networks becomes more challenging. In this paper, we propose a framework for the distributed detection of FDIAs in large-scale sensor networks. By extracting the spatiotemporal correlation information from sensor data, the large-scale sensors are categorized into multiple correlation groups. Within each correlation group, an autoregressive integrated moving average (ARIMA) is built to learn the temporal correlation of cross-correlation, and a consistency criterion is established to identify abnormal sensor nodes. The effectiveness of the proposed detection framework is validated based on a real dataset from the U.S. smart grid and simulated under both the simple FDIA and the stealthy FDIA strategies.
This article describes an inexpensive partitioned coupling strategy for computational fluid–structure interaction (FSI) admitting negative‐Jacobian elements. The emphasis is very much on a reduced ...smoothed integration (RSI) scheme of the cell‐based smoothed finite element method (CSFEM) using four‐node quadrilateral (Q4) elements for a cost‐effective solution to the Navier–Stokes (NS) equations. In the discrete fluid field, each Q4 element is considered as one single smoothing cell so as to diminish the smoothed integration loops substantially. However, the RSI scheme does not respect the stability condition of smoothed Galerkin weak‐form integral in the CSFEM. To tackle this issue, a simple hourglass control is introduced to the under‐integrated formulation of the NS solver. Importantly, the stabilized RSI scheme has an inbuilt advantage of its enormous tolerance towards negative‐Jacobian elements. The developed technique is easy‐to‐implement and has been tested in various FSI examples adopting both fine and distorted meshes.
This article develops a reduced smoothed integration (RSI) scheme of the cell‐based finite element method for fluid‐structure interaction. After introducing an hourglass control to the under‐integrated formulation, the RSI scheme has an inbuilt advantage of its enormous tolerance towards negative‐Jacobian elements. The proposed technique is tested, with good accuracy and higher efficiency, through various examples adopting fine and damaged meshes.
Advanced persistent threat (APT) is a new kind of cyberattack that poses a serious threat to modern society. When an APT campaign on an organization has been identified, the available repair ...resources must be reasonably allocated to the potentially insecure hosts to mitigate the potential loss of the organization. We refer to the feasible repair resource allocation strategies as repair strategies. This paper focuses on the APT repair problem, i.e., the problem of developing effective repair strategies for organizations. First, for an organization with time-varying communication relationship, we establish an evolution model of the organization's expected state, in which the impact of lateral movement of APT is accommodated. On this basis, we model the APT repair problem as a differential Nash game problem (the APT repair game) in which the attacker attempts to maximize his potential benefit, and the organization manages to minimize its potential loss. Second, we derive a system (the potential system) for calculating a potential Nash equilibrium of an APT repair game, and we examine the structure of the potential attack and repair strategies in a potential Nash equilibrium. Next, we solve some potential systems to get the corresponding potential Nash equilibria. Finally, by comparison with a large number of randomly generated attack and repair strategies, we conclude that the potential Nash equilibrium of each APT repair game is a Nash equilibrium of the game. Therefore, we recommend to organizations their respective potential repair strategies. Our findings help to better understand and effectively defend against APT.
A new high step-up interleaved converter is proposed in this paper. This new high step-up converter utilizes the interleaved boost converter to be in series connection with the voltage-double module. ...The secondary sides of the coupled inductors are in interleaved series connection and shared by two voltage-double modules to accomplish the interleaved energy storage. Then, the input voltage, coupled-inductors, and multiplier capacitors are in series connection with the output to achieve the purpose of high voltage gain. The proposed circuit can be operated at a lower duty cycle to achieve high voltage gain by adjusting the turn ratio of the coupled inductors. The proposed circuit has less elements and the voltage stress of the switches and diodes can be decreased to reduce the cost. The conduction loss can be reduced and the efficiency can be increased when the switch with lower conduction resistance is applied. Finally, a prototype circuit of a 400 W high step-up converter with input voltage of 24 V and output voltage of 400 V is realized. Through simulation and experiments, the validity and property of the proposed converter can be verified.
PDF
