重新找回人工智能的可解释性

针对深度神经网络AI研究的可解释性瓶颈，指出刚性逻辑（数理形式逻辑）和二值神经元等价，二值神经网络可转换成逻辑表达式，有强可解释性。深度神经网络一味增加中间层数来拟合大数据，没有适时通过抽象把最小粒度的数据（原子）变成粒度较大的知识（分子），再把较小粒度的知识变成较大粒度的知识，把原有的强可解释性淹没在中间层次的汪洋大海中。要支持多粒度的知识处理，需把刚性逻辑扩张为柔性命题逻辑（命题级数理辩证逻辑），把二值神经元扩张为柔性神经元，才能保持强可解释性。本文详细介绍了从刚性逻辑到柔性逻辑的扩张过程和成果，最后介绍了它们在AI研究中的应用，这是重新找回AI研究强可解释性的最佳途径。     

Neutron Diffraction and Neutron Radiography Investigation into Powder Sintering of Ti/Al and TiH2/Al Compacts

Metallurgical and Materials Transactions B - Sintering behaviors of two types of powder compact, i.e., Ti/Al and TiH2/Al, under vacuum were studied using in situ neutron diffraction, in situ...     

不同热解工艺下半焦的微观结构特点及其对燃烧性能的影响

摘要：对比研究了3种直立内热炉半焦(熄焦方式分别为水泡熄焦、喷水熄焦及烟气干熄焦)及一种流化床热解半焦的微观结构及燃烧性能。通过对半焦组成、孔隙结构、有机官能团、碳化学结构及半焦微晶结构分析，获得了不同低温热解工艺半焦的组成及微观结构特点，明确了组成及微观结构与燃烧性能之间的关系。结果表明，不同热解工艺半焦的组成和微观结构差异明显，其对半焦的燃烧性能影响显著。干熄焦碳化学结构缺陷比例大，快速热解半焦孔隙结构发0达、挥发分高，与水喷焦相比水泡焦石墨化程度低；水喷焦燃烧性能优于水泡焦，干法所得半焦的燃烧性优于湿法；半焦的挥发分含量决定其燃点，在快升温速率条件下孔隙结构对半焦的燃烧性能影响较大，而慢升温速率条件下有序化度对半焦的燃烧性能影响较大。     

Multi-user image encryption algorithm based on synchronized random bits generator in semiconductor lasers network

A chaos-based public channel image encryption algorithm among three users is proposed, where the random bits (RBs) generated in a star-type chaotic laser network can be well synchronized and are used as the keys. The proposed algorithm is simple and efficient. Firstly, random bits with verified randomness are generated from the synchronized chaotic semiconductor lasers in a star-type network at a rate of 10Gb/s. Next, lower-triangular error-bits detection is employed to delete the different bits among all the parties over the public channel. Based on the synchronized RBs, the XOR operation is used to diffuse the plain image. Then the hash algorithm is used to get the control parameters matrix from the plain image, and 3D cat map is used to confuse the pixel position through the parameters matrix. Finally, the encrypted image is transmitted in the public channel. The performance tests results, such as key sensitivity, histogram, correlation, differential attack, robustness and entropy analysis, show that the suggested algorithm prevents a powerful computational eavesdropper. Besides, the running speed of this algorithm is linear with the size of plain image. These results open possibilities for multi-user secure communication application.

     

Double polarization hysteresis and dramatic influence of small compositional variations on the electrical properties in Bi4Ti3O12 ceramics

This work reports the existence of double polarization hysteresis (P–E) loop in Aurivillius-phase ferroelectric Bi₄Ti₃O₁₂ (BiT) and reveals dramatic influence of small compositional variations on the electrical properties of it. The double polarization hysteresis is a characteristic of the interaction of defects with domain walls. This characteristic becomes more pronounced in Bi-deficient and Mg-doped BiT due to an increase in oxygen vacancy concentration at the lattices. Normal and saturated P–E loop is recalled by Nb donor doping, and associated composition Bi₄Ti_2.97Nb_0.03O_12.015 (BiT-0.03Nb) shows high remnant polarization (P_r = 12.5 μC/cm²) and large field-induced strain (S₃₃ = 5.6 × 10^?4). In addition, this doping results in bulk conductivity (σ_b) of BiT decreasing dramatically and associated activity energy (E_a) increasing significantly. In contrast, high oxide ion conductivity is induced with Mg²⁺ acceptor doping, and at 600 °C the optimum composition has ionic conductivity of ?0.65 × 10^?2 S cm^?1 in the bulk.     

A Channel Borrowing Approach for Cluster-based Hierarchical Wireless Sensor Networks

Mobile Networks and Applications - In Wireless Sensor Networks (WSNs), energy-efficient routing is required to conserve the scarce resources of these networks. Various energy-efficient routing...     

Excellent Energy Storage and Charge-discharge Performances in PbHfO3 Antiferroelectric Ceramics

Single phase PbHfO₃ antiferroelectric ceramics were prepared via rolling process. It is revealed that the rolling process can reduce the grain size and increase the bulk density, which lead to the enhanced breakdown strength up to 268 kV/cm versus 219 kV/cm of samples using the conventional solid-state method. As a result, high recoverable energy density of 7.6 J/cm³ with an efficiency of 80.8 % was achieved. Meanwhile, a large current density of 1381 A/cm² and an ultrahigh peak power density up to 170 MW/cm³ were observed under 250 kV/cm. In addition, unique electrical polarization response characteristics at different electric fields and temperature-induced structural phase transitions were also investigated. The energy storage performance and charge-discharge properties of PbHfO₃ were first studied in this communication and all the results indicate that PbHfO₃ ceramic is a promising candidate for pulse power applications.     

Evolution of linear edge dislocation in atmospheric turbulence and free space

In accordance with the extended Huygens–Fresnel principle, the evolution of linear edge dislocation propagating through atmospheric turbulence is studied, and the effects of waist width and the slope of linear edge dislocation are investigated. It is shown that when linear edge dislocation beams propagate through atmospheric turbulence, if the waist width is not equal and the slope is not zero, then the linear edge dislocation vanishes and transforms into an optical vortex with a topological charge of ?1 or +1. The optical vortex and an optical vortex that is created annihilate when the transmission distance is far enough. The linear edge dislocation vanishes when the slope is zero. If the waist width is equal, then the linear edge dislocation will vanish regardless of the slope value. For linear edge dislocation beams in free space, when selecting specific parameters, linear edge dislocation always exists.     

Co-coating effect of GdPO4 and carbon on LiFePO4 cathode surface for lithium ion batteries

The electronic conductivity enhanced has been extensively studied and reported in lithium iron phosph-ate (LiFePO₄). However, only few existing literatures are available for researchers to enhance simultaneously the ion and electronic conductivity of LiFePO₄. Herein, we disclose that the LiFePO₄ is co-coated with novel GdPO₄ and Carbon via a hydrothermal-assisted solid-phase method, contributing to particle size and dispersibility. What surprising is that the ionic and electronic conductivity of the material is significantly enhanced, and the interfacial side reaction is effectively inhibited between the materials and the electrolytes. The diverse proportions of the mixed coating (LiFePO₄/C&xGdPO₄ (x = 0, 1 wt%, 2 wt%, 3 wt%, 4 wt%)) are synthesized compared with bare LiFePO₄. The experimental results suggest that LiFePO₄/C&0.03GdPO₄ exhibits the most excellent electrochemical performance. There is discharge capacity of 158, 148.8, 141.6, 134.9, 121.8, 104.9, and 86.7mAh/g at 0.1, 0.2, 0.5, 1, 2, 5, and 10 C rates, respectively.     

Ab initio calculations of the NO2 fission for CL-20 conformers

NO₂ fission is regarded to be the most important initial decomposition process of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20). In this study, four CL-20 conformers based on the ε-CL-20 were obtained after the optimization at m062x/cc-pvtz level, and the bond length, bond order and bond dissociation energy of the N-N bonds were examined to investigate the stability of these bonds. In addition, the rate constants and activation energy of the NO₂ fission were evaluated using the microcanonical variational transition state theory (μVT). The calculation results have shown that N-N bonds in the case of pseudo-equatorial and axial of nitro groups are the most stable and the least stable, respectively, by evaluating the bond length, bond order and minimum energy path (MEP). The NO₂ fission rate constants are affected by not only the stability of N-N bonds but also the repulsion forces from the other nitro groups, and the fission process for pseudo-equatorial positioning of nitro groups is easier to be accelerated due to the increase of the repulsion forces. The decomposition of CL-20 conformer may mainly originate from the fission of the pseudo-equatorial positioning of nitro groups, especially for CL-20 III conformer because of the significant low activation energy.