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Since the summer of 2017, bacterial fruit black rot disease was observed on prickly ash (Zanthoxylum armatum DC., Yongqing No. 1) in three counties (Yongshan, Qiaojia and Ludian) of Zhaotong City, Yunnan Province, that kills the fruit, results in significant yield reduction, severely affects quality of fruit and even worst has no harvest. A combination of cultural, biochemical and physiological characterizations, Biolog analyses, MALDI-TOF MS analyses, multi-locus phylogenetic analyses and pathogenicity assays revealed that Pseudomonas oryzihabitans was the pathogen associated with the fruit black rot. The pathogenicity was verified with Koch’s postulates. To our knowledge, this study provides the first report of fruit black rot caused by P. oryzihabitans on prickly ash.

In Harbin, Heilongjiang, China, a shoot blight of Caragana arborescens exhibiting light brown-to-brown sunken lesions with immersed fruiting bodies was observed during May through October of 2017. A survey was conducted to determine the extent and severity of the disease. In May 2017, a total of 12 diseased C. arborescens trees were found among 80 samples, with a field infection rate of 15%. Twelve random branches showing symptoms were collected and examined for symptoms and signs. Phylogenetic analysis, morphology, and isolate pathogenicity towards C. arborescens after inoculation of 20 healthy branches with spore suspensions revealed a new pathogenic species causing the shoot disease, which is described here as Phaeobotryon caraganae. P. caraganae is a new species and causes C. arborescens shoot disease. Future research on Phaeobotryon is important to improve our understanding of shoot diseases.

In May 2018, a bacterial tumor disease was observed on Populus koreana in Shuangyang county, Changchun city, Jilin Province. Based on physiological characteristics, Biolog and genetic sequences analysis, the bacterium was identified as Pseudomonas aeruginosa. The pathogenicity was verified with Koch’s postulates. To our knowledge, this is the first report of tumor disease caused by P. aeruginosa on P. koreana.

Mulberry has tremendous economic importance and cultivated widely across China. In June 2018, branch blight disease was found on mulberry (Morus alba) in Harbin City, Heilongjiang Province. Based on morphological characteristics and genetic sequences analysis, the pathogenic fungus was identified as Aplosporella javeedii. The pathogenicity was verified with Koch’s postulates. To our knowledge, this study provides the first report of A. javeedii causing mulberry branch blight in the word.

In August 2018, Asian mistletoe (Viscum coloratum) branch and leaf spots were found in Loufan, Shanxi Province, China. Morphological and molecular identifications confirmed the isolation of Seimatosporium falcatum. The pathogenicity was verified with Koch’s postulates. To our knowledge, this is the first report of S. falcatum as a pathogen of V. coloratum in China.

The increasing share of renewables in energy systems requires energy storage technologies to handle intermittent energy sources and varying energy sinks. Liquid air energy storage (LAES) is a promising technology since it has a high energy density and is not geographically constrained. A relatively high round-trip efficiency (RTE) is obtained by using hot and cold energy recovery cycles in the LAES. In this work, seven cases related to different cold energy recovery cycles are optimized and compared for a standalone LAES system. Multi-component fluid cycles (MCFCs) and Organic Rankine Cycles (ORCs) are considered for the first time to be used as cold recovery cycles in the LAES. The optimal results show that the LAES system with dual MCFC has the best performance with an RTE of 62.4%. This RTE can be further increased to 64.7% by reducing the minimum temperature difference of high-temperature heat exchangers from 10 °C to 5 °C. Optimization results also indicate that ORCs used in the cold energy recovery system are not producing any work, and only phase change of the working fluid takes place, thus they should not be used. Finally, the exergy transfer effectiveness is applied to measure thermodynamic performance of the charging and discharging processes.

Renewable energy sources have a growing share in the energy market due to the threat from climate change, which is caused by emissions from fossil fuels. A future energy scenario that is likely to be realized is distributed energy systems (DES), where renewable energy sources play an increasing role. Energy storage technologies must be adopted to achieve these two expectations. Liquid Air Energy Storage (LAES), is a cryogenic technology that is discussed in this paper. Two cases are considered in this work to represent different operating modes for the LAES process: with and without an extra amount of hot oil in the discharging process. The performance of the LAES system will be analyzed with different number of compression stages and expansion stages in each mode. A Genetic Algorithm (GA) is used to optimize the LAES process. The round-trip efficiency is 63.1 % after flowsheet improvement and optimization.

Energy supply is an essential factor for a country’s development and economic growth. Currently, our energy system is dominated by fossil fuels that produce greenhouse gases. Thus, it is necessary to switch to renewable energy forms and increase efforts in waste-to-energy systems. However, once renewable energy sources are introduced in the industrial system, the most important considerations are stability and sustainability of the energy supply because of the intermittency of renewable energy. Based on the previous considerations, storage technologies for electrical energy are discussed to compensate for this problem. A few mature technologies are introduced, such as pumped hydroelectric energy storage (PHES), compressed air energy storage (CAES), H2 energy storage and batteries. However, they have not been widely applied due to some limitations such as geographical constraints, high capital costs and low system efficiencies. Liquid air energy storage (LAES) has the potential to overcome the drawbacks of the previous technologies and can integrate well with existing equipment and power systems. In this chapter, the principle of LAES is analysed, and four LAES technologies with different liquefaction processes are compared. Four evaluation parameters are used: round-trip efficiency, specific energy consumption, liquid yield and exergy efficiency. Capacity and response time are also essential properties. The results indicate that LAES with hot and cold energy storage has considerable advantages over the other processes. Finally, the prospects of a hybrid system with higher system efficiency and performance, where LAES is integrated with renewable energy, waste heat and batteries are discussed.

The focusing nonlinear Schrodinger equation (NLSE) is a universal model for studying solitary waves propagation in nonlinear media. The NLSE is especially important in understanding how solitons on a condensate background (SCB) appear from a small perturbation through modulation instability. We study theoretically the one- and two-soliton solutions of the NLSE in presence of a condensate by using the dressing method. It is found that a class of bipolar elliptically polarized solitons with the choice of specific parameters in the one- and two-soliton solutions. Collisions among these solitons are studied by qualitative analysis and graphical illustration. We also generalize the concept of the quasi-Akhmediev breather to the bipolar solitons and show how it can be used for wave profile compression down to the extremely short duration. Our results extend previous studies in this area of the SCB and play an important role in the theory of freak wave.

In this paper, some means are proposed to improve the performances of the set-top box (STB) based media distribution schemes for IPTV. Firstly, the lightweight packet encryption is used to replace traditional complete encryption in order to reduce the time cost. Secondly, a method is introduced to form a unique customer code and generates a unique media copy for each customer in order to trace illegal redistributors. Thirdly, the desynchronization operations are introduced to make different copies in order to resist collusion attacks. Analyses and experiments show that the proposed packet encryption saves much time cost compared with traditional encryption and the saved time cost is enough for the added new operations. Additionally, the produced media copy is different from each other, and their collusion will generate a copy with much degradation, which can resist the content leakage from the gap between STB and TV set.

A scheme is proposed to implement commutative video encryption and watermarking during advanced video coding process. In H.264/AVC compression, the intra-prediction mode, motion vector difference and discrete cosine transform (DCT) coefficients' signs are encrypted, while DCT coefficients' amplitudes are watermarked adaptively. To avoid that the watermarking operation affects the decryption operation, a traditional watermarking algorithm is modified. The encryption and watermarking operations are commutative. Thus, the watermark can be extracted from the encrypted videos, and the encrypted videos can be re-watermarked. This scheme embeds the watermark without exposing video content's confidentiality, and provides a solution for signal processing in encrypted domain. Additionally, it increases the operation efficiency, since the encrypted video can be watermarked without decryption. These properties make the scheme a good choice for secure media transmission or distribution

Kilowatt Ytterbium-doped fiber laser is found widespread application in medical technology, industry and military areas. At present, most of the multi-kilowatt single-mode fiber lasers are achieved by tandem-pumped master oscillator power-amplifier (MOPA) system. When the laser output power reaches kilowatt, the output will be strongly affected by nonlinear effects in the amplifier. The Stimulated Raman Scattering effects is known as the major restrictions to the increase of output signal power. Up to now, Raman effects in conventional diode-pumped amplifier have been well studied while the Raman effects in tandem-pumped has not yet been thoroughly analyzed. In this paper, a theoretical analysis of Raman effects using numerical solution of steady-state rate equations in kilowatts tandem-pumped ytterbium-doped fiber amplifiers is presented. The numerical simulation describing output power characteristics and laser distribution along the fiber is carried under the co-directional end-pumping. Furthermore, an optimization of Raman effects is discussed, which provides a solid foundation for achieving a higher fiber laser output.

Advanced video coding is recently announced and widely used, although the according protection means have not been developed thoroughly. In this paper, a secure AVC coding scheme is presented based on some partial encryption algorithms. During AVC encoding, such sensitive data as intra-prediction mode, residue data and motion vector are encrypted partially. Among them, the infra-prediction mode is encrypted based on exp-Golomb entropy coding, the intra-macroblocks' DCs are encrypted based on context-based adaptive variable length coding (CAVLC), and infra-macroblocks' ACs and the inter-macroblocks' MVDs are sign-encrypted with a stream cipher followed with variable-length coding. This encryption scheme is secure in perception, keeps format compliance, and obtains high time efficiency though reducing the encrypted data volumes. These properties make it practical to incorporate encryption/decryption process into compression/decompression process, and thus suitable for secure video transmission or sharing.

The formation of extreme localization structures in nonlinear dispersive media (water or optical fibres) can be explained and described by the focusing nonlinear Schrodinger equation (NLSE). The NLSE is especially important in understanding how solitons on a condensate background (SCB) appear from a small perturbation through modulation instability. We have studied theoretically SCB solutions solved with the dressing method. A class of bipolar-rogue-wave structures that are constructed by collisions between elementary SCB or bipolar solitonic solutions was found. Besides, we have also found a new class of regular bright solitonic rogue waves that are originated from the collision between two bipolar-rogue-wave structures. The bipolar-rogue-wave structures can be considered to provide a new prototype for rogue-waves dynamics modeling. Our results extend previous studies in the area of rogue waves and may be important in the study of oceanography and optics.

The aerobic biodegradation of lignin was studied by running an activated sludge reactor in laboratory. The results show that the pH of the effluent changes little between 7.2 and 7.6, and the aerobic biodegradation ratio of lignin is more than 40%. The sludge characters are improved apparently as the reactor runs with time. In conclusion, the aerobic microbe groups which can decompose lignin have been cultivated in the reactor. Besides, cometabolic substrate has great influence on the aerobic biodegradation of lignin. When the mass proportion of glucose occupies 5% in the influent, lignin decomposition efficiency reaches the highest value of 49%. However, lignin can't be completely biodegraded by these aerobic microbe groups because the chemical groups which have a strong absorbance at ultraviolet 276nm can't be damaged easily by these microorganisms.