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As more traditional businesses, such as banking and finance, are transferred to online platforms or the cloud, the deepening of system interaction with users and the improvement of technology-based defence system make cyber attackers focus more on human beings, leading to serious financial consequences. This attack utilising social engineering often exploits human nature's weakness. Its complexity, language variability and inductivity are difficult to defend effectively. Therefore, this paper proposes a model for detecting social engineering attacks based on deep neural network by reviewing current methods for social engineering detection, in terms of phishing, deception and content-based detection, in addition to examining deep learning algorithms with excellent data performance. Through the processing and analysis of natural language in chat history, the attention-based Bi-LSTM is used to capture and mine the context semantics, and the ResNet is used to integrate user characteristics and content characteristics for classification and judgment. By describing the features of social engineering attacks and online conversations, the feasibility and effectiveness of the proposed model are demonstrated from the perspective of algorithm selection and applicability.

Abstract The effect of three-dimensional leakage on the extrapolated endpoint, Z 0 , is studied for non-multiplying, pulsed systems. The three-dimensional nature of the problem is treated accurately by modifying a method developed in an earlier publication on the diffusion length problem. Results are obtained using realistic scattering models for hydrogenous and polycrystalline moderators, and also in the 1-speed approximation, assuming isotropic scattering. The theory is compared with experimental values for particular systems. The variation of Z 0 with B 2 is demonstrated for cubical systems: Z 0 is found to decrease with increasing B 2 for hydrogenous and polycrystalline materials. This dependence is explained by considering the asymptotic spectra and the energy dependence of the neutron mean free path. Tables of Z 0 are included so that experimenters may deduce B 2 for non-cubic systems. The anisotropy of Z 0 is demonstrated by computing the value for each direction of a rectangular parallelepiped.

Abstract Pyrolysis tar and char yields were measured at atmospheric pressure between 400–800 °C in three reactors with significantly different design characteristics: a fluidized bed; a wire-mesh reactor; and a ‘hot-rod’ fixed bed reactor. Ranges of conditions under which results were generally in good agreement were identified using a common sample of Linby (low rank British bituminous) coal. Differences highlighted important non-ideal characteristics in the behaviour of all three systems. The causes of these non-idealities and their implications for the interpretation of pyrolysis data from the three types of reactors are discussed in detail.

Abstract In this study, a methodology is developed to assess the feasibility of a reverse osmosis (RO) desalination system powered by a stand-alone salinity driven pressure retarded osmosis (PRO) technology. First, the proposed hybrid RO–PRO system is analysed as a thermodynamic cycle and its feasibility is mathematically interpreted using a feasible condition (FC) number, several dimensionless operational variables and a number of constraints to represent the objective of zero brine discharge. Then, a study of the stand-alone feasibility of a hybrid seawater RO–PRO system is carried out. The results show that lower RO water recovery and higher dimensionless flow rate improve the stand-alone feasibility of the system. A subsystem, a look inside the PRO, is developed to study the applied pressure and the required membrane area to achieve the operations with optimum FC numbers. It is found that the optimum applied hydraulic pressure is inversely proportional to the dimensionless flow rate in the feasible range of stand-alone operations and more area of membrane is required by a larger FC number. Finally, a case study of a selected operation is presented based on its energy performance, and two influencing factors, the inefficiency of the components and the salinity concentration of the feed water.

This study aims to systematically evaluate the detrimental effects, namely concentration polarization (CP) and reverse solute permeation (RSP), and search for the optimum performance of a scale-up osmotic power assisted reverse osmosis (RO) desalination plant. The simulation clearly shows the performance reductions of the hybrid RO-PRO plant due to the CP and RSP effects. However, in both the co-current and counter-current PRO configurations, when the overall dimensionless flow rate decreases, these performance reductions become less significant. In addition, the counter-current PRO has high effectiveness because of the low theoretical net specific energy consumption (SEC) of RO-PRO. It is observed that more severe reduction due to the CP and RSP effects at high overall dimensionless flow rate shrinks the advantageous performance. Furthermore, PRO feed solutions with different concentrations are studied to evaluate the overall performance of the hybrid system. The results indicate that the advantageous performance can be achieved in a range of the concentration of the PRO feed. And with the increase on the PRO feed concentration, the osmotic energy generation reduces but the un-extracted energy due to the detrimental effects is also reduced.

Phenomena well known in chemical spectroscopy are used to explain muscular contraction; fundamental reasons for excluding alternative explanations are outlined.

As bioethanol from sugarcane and wheat falls out of favour due to concerns about food security, research is ongoing into genetically engineering model plants and microorganisms to find the optimum cell wall structure for the ultimate second generation bioethanol crop. Charis Cook and Alessandra Devoto highlight here the progress made to tailor the plant cell wall to improve the accessibility of cellulose by acting on the regulation, the structure or the relative composition of other cell wall components to ultimately improve saccharification efficiency. They also consider possible side effects of cell wall modification and focus on the latest advances made to improve the efficiency of digestion of lignocellulosic materials by cell wall degrading microorganisms.

Concentrations of corticosterone in brain areas of TO strain mice were measured by radioimmunoassay. The studies examined the effects of routine laboratory maneuvers, variation during the circadian peak, adrenalectomy, social defeat and acute injections of alcohol on these concentrations. Brief handling of mice increased corticosterone levels in plasma but not in striatum and reduced those in the hippocampus. Single injections of isotonic saline raised the plasma concentrations to a similar extent as the handling, but markedly elevated concentrations in the three brain regions. Five minutes exposure to a novel environment increased hippocampal and cerebral cortical corticosterone levels and striatal concentrations showed a larger rise. However, by 30 min in the novel environment, plasma concentrations rose further while those in striatum and cerebral cortex fell to control levels and hippocampal corticosterone remained elevated. Over the period of the circadian peak the hippocampal and striatal concentrations paralleled the plasma concentrations but cerebral cortical concentrations showed only small changes. Adrenalectomy reduced plasma corticosterone concentrations to below detectable levels after 48 h but corticosterone levels were only partially reduced in the hippocampus and striatum and remained unchanged in the cerebral cortex. Single or repeated social defeat increased both brain and plasma concentrations after 1 h. Acute injections of alcohol raised the regional brain levels in parallel with plasma concentrations. The results show that measurements of plasma concentrations do not necessarily reflect the levels in brain. The data also demonstrate that corticosterone levels can change differentially in specific brain regions. These results, and the residual hormone seen in the brain after adrenalectomy, are suggestive evidence for a local origin of central corticosterone.

Abstract A least squares principle is described which uses a penalty function treatment of boundary and interface conditions. Appropriate choices of the trial functions and vectors emplyoed in a dual representation of an approximate solution established complementary principles for the diffusion equation. A geometrical interpretation of the principles provides weighted residual methods for diffusion theory, thus establishing a unification of least squares, variational and weighted residual methods. The complementary principles are used with either a trial function for the flux or a trial vector for the current to establish for regular meshes a connection between finite element, finite difference and nodal methods, which can be exact if the mesh pitches are chosen appropriately. Whereas the coefficients in the usual nodal equations have to be determined iteratively, those derived via the complementary principles are given explicitly in terms of the data. For the further development of the connection between finite element, finite difference and nodal methods, some hybrid variational methods are described which employ both a trial function and a trial vector.