Recent Development of Bioenergy and Biorefinery in China

Although energy was used throughout the history of human culture, the burst of energy production and consumption coincided with the beginnings of the Industrial Revolution. The transition from hand production methods to machines, the increasing exploration and use of fossil-derived fuels (coal, petroleum, natural gas, shale fuel) made it possible to production of energy in large quantities. The majority of global energy supply still relies on traditional fossil based energy, with abundant fossil feedstock, well-understood technologies, and significant advantages in economy and scale. However, the traditional energy industry is now being challenged by sustainability of feedstock supply and environmental pressures, especially for carbon emission issues. Reduce the use of fossil fuels and replace them by renewable energies has been widely accepted by scientists, businesses and governors. Up to date, alternative renewable energy can be industrially produced via an extensive range of processes and sources like solar, wind, hydro, nuclear and bioenergy. According to the data of World Bioenergy Association (www. worldbioenergy.org), bioenergy has now been the largest global renewable energy supply which only below the traditional fossil energy.China has abundant biomass resources to about 0.4 billion tons per year - if totally utilized the bioenergy can satisfy 10% of total energy consumption in China. However, the current utilization of bioenergy in China is of low efficiency: with immature technologies, in small production scales and hard to satisfy the market demands. For example, in global level, the final energy from biomass is bioheat, followed by transport fuels (mainly as corn/cellulose ethanol, biodiesel) and electricity. While in China, bioelectricity is the main form of bioenergy, large quantities of biomass are not efficiently utilized. Straw burning can be widely seen in agriculture area at harvesting season, which not only waste the valuable bioresources but also cause severe air pollution.Currently, national projects are prompted in research and pilot level to improve the quantity and quality of Chinese bioenergy framework. Integrated production process for both bioheat and electricity was developed in recent years which aimed to improve the conversion efficiency of bioenergy. Super biogas projects are prompted in many regions where has abundant biomass resources. Second generation bio-ethanol is in pilot scale production, which utilizes the non-food agriculture waste like the corncobs. Moreover, biorefinery and bioconversion of the biomass to value added products are in early stages of development. Exploration of advanced bio-fuels and value-added chemical building blocks using modern techniques are future trends in the business of bioenergy and biorefinery. A variety of bio-, chemo- processes may be integrated in convertion of the biomass to the complex products. For example, Sinopec, one of the Chinese leading chemical companies, has explored 1st generation of bio-jet fuel, which is made from waste cooking oil via a variety of chemical processing techniques. Similar projects are in fast developing by industries as well as the research institutes.It is hard to answer what is the future of bioenergy and biorefinery in China. As nobody in the last century can predict the scale and the diversity of the relative business of bioenergy in nowadays. But this industry will have a promising future: a seemingly infinite and renewable bio- resources in our lands, huge members of industries, governments and research institutes are eager to contribute their endeavors in this fast developing field, and more discoveries and modern techniques will be unfolded in the near future. We will walk a long way to fill in the gap between pioneering projects and conceptions and the practical scale-up application in this field.Citation: Xian, M. (2015). Recent Development of Bioenergy and Biorefinery in China. Trends in Renewable Energy, 1(3), 129-130. DOI: 10.17737/tre.2015.1.3.001

Constructions of bent functions from two known bent functions

A (1, -1)-matrix will be called a bent type matrix if each row and each column are bent sequences. A similar description can be found in Carlisle M. Adams and Stafford E. Tavares, Generating and counting binary sequences, IEEE Trans. Inform. Theory, vol. 36, no. 5, pp. 1170-1173, 1990 in which the authors use the properties of bent type matrices to construct a class of bent functions. In this paper we give a general method to construct bent type matrices and show that the bent sequence obtained from a bent type matrix is a generalized result of the Kronecker product of two known bent sequences. Also using two known bent sequences of length 22k-2 we can construct 2k-2 bent sequences of length 22k more than in the ordinary construction, which gives construct 10 bent sequences of length 22k from two known bent sequences of length length 22k-2

The kth-order nonhomomorphicity of S-boxes

Nonhomomorphicity is a new nonlinearity criterion of a mapping or S-box used in a private key encryption algorithm. An important advantage of nonhomomorphicity over other nonlinearity criteria is that the value of nonhomomorphicity is easy to estimate by the use of a fast statistical method. Due to the Law of Large Numbers, such a statistical method is highly reliable. Major contributions of this paper are (1) to explicitly express the nonhomomorphicity by other nonlinear characteristics, (2) to identify tight upper and lower bounds on nonhomomorphicity, and (3) to find the mean of nonhomomorphicity over all the S-boxes with the same size. It is hoped that these results on nonhomomorphicity facilitate the analysis and design of S-boxes

Nonlinearity and propagation characteristics of balanced boolean functions

Three of the most important criteria for cryptographically strong Boolean functions are the balancedness, the nonlinearity and the propagation criterion. The main contribution of this paper is to reveal a number of interesting properties of balancedness and nonlinearity, and to study systematic methods for constructing Boolean functions satisfying some or all of the three criteria. We show that concatenating, splitting, modifying and multiplying (in the sense of Kronecker) sequences can yield balanced Boolean functions with a very high nonlinearity. In particular, we show that balanced Boolean functions obtained by modifying and multiplying sequences achieve a nonlinearity higher than that attainable by any previously known construction method. We also present methods for constructing balanced Boolean functions that are highly nonlinear and satisfy the strict avalanche criterion (SAC). Furthermore we present methods for constructing highly nonlinear balanced Boolean functions satisfying the propagation criterion with respect to all but one or three vectors. A technique is developed to transform the vectors where the propagation criterion is not satisfied in such a way that the functions constructed satisfy the propagation criterion of high degree while preserving the balancedness and nonlinearity of the functions. The algebraic degrees of functions constructed are also discussed, together with examples illustrating the various constructions

A Bridge Between Two Worlds: a Cultural Interpretation of Dragonwings

Living in the dual worlds of his life as a Chinese American and in places such as Chinatown, Laurence Yep felt that he was culturally alienated and that he did not have a culture of his own. With the driving wish to find out about Chinese culture―his culture, he finished his best known novel Dragonwings after six years of research on Chinese culture. Based on the true story of Fung Joe Guey, a Chinese American who built and flew an airplane in the Oakland hills in 1909, Dragonwings tells the story of Moon Shadow, who comes to San Francisco to join his unknown father, Windrider, who cherishes the dream of flying. To pursue the dream, Moon Shadow and his father have to move out of Chinatown. After enduring a sea of misunderstanding, cruelty and poverty, Windrider finally realizes his flying dream with the support and aid of his beloved son and his fellowmen, as well as his American friends. Trying to show the process from misinterpretation and misunderstanding to mutual understanding and the possibilities of cultural exchange and cultural fusion between two different cultures, we will discuss how the Chinese culture is rediscovered by a Chinese American and how cultural misunderstanding leads to an unbalanced world and how tolerance and understanding restore the world into a harmonious one. This paper attempts to demonstrate, through the analysis of Dragonwings, the author’s exploration of Chinese culture, cultural exchange and human nature transcending cultural differences. Key words: Dragonwings, Laurence Yep, cultural exchange Abstrait: En vivant dans le monde dual de sa vie comme Américain chinois et aux endroits comme la Cité chinoise, Laurence Yep trouve qu’il était aliéné culturellement et qu’il n’avait pas de culture de sa ville. Avec l’espoir violent à découvrir la culture chinoise----sa culture, il a achevé son roman bien connu Dragon-ailes après une recherche de six années sur la culture chinoise. Basé sur l’histoire vraie de Fung Joe Guey , un Américain Chinois qui a fabriqué et manié un avion dans les Montagnes Oakland en 1909, Dragon-ailes raconte le conte de Ombre de lune, qui vient à San Francisco pour rejoindre son père inconnu , Windrider, qui a le rêve de voler .Poursuivant le rêve, Ombre Lunaire et son père sont obligés de bouger de la Cité chinoise. Après avoir enduré une mer d’incompréhension , de cruauté et de pauvreté, Windrider a finalement réalizé son rêve de voler avec l’aide de son fils et ses compagnons, ainsi que ses amis américains. Essayant de montrer le processus de malinterprétation et de incompréhension à compréhension mutuelle et les possibilités d’échange et de fusion culturels entre deux cultures différentes, nous discuterons comment la culture chinoise est redécouverte par un Américian chinois et comment l’incompréhension culturelle conduit à un monde inégal et comment la tolérance et la compréhension reconstruisent le monde à celui d’harmonique. Ce papier tente de démontrer , à travers l’analyse de Dragon-ailes , l’exploration de l’auteur de la culture chinoise , de l’échange culturel et des différences transcendantes naturelles de la nature humaine. Mots clefs: Dragon-ailes, Laurence Yep, échange culture

Biotechnological production of 1,2,4-butanetriol: An efficient process to synthesize energetic material precursor from renewable biomass

1,2,4-Butanetriol (BT) is a valuable chemical with extensive applications in many different fields. The traditional chemical routes to synthesize BT suffer from many drawbacks, e.g., harsh reaction conditions, multiple steps and poor selectivity, limiting its industrial production. In this study, an engineered Escherichia coli strain was constructed to produce BT from xylose, which is a major component of the lignocellulosic biomass. Through the coexpression of a xylose dehydrogenase (CCxylB) and a xylonolactonase (xylC) from Caulobacter crescentus, native E. coli xylonate dehydratase (yjhG), a 2-keto acid decarboxylase from Pseudomonas putida (mdlC) and native E. coli aldehyde reductase (adhP) in E. coli BL21 star(DE3), the recombinant strain could efficiently convert xylose to BT. Furthermore, the competitive pathway responsible for xylose metabolism in E. coli was blocked by disrupting two genes (xylA and EcxylB) encoding xylose isomerase and xyloluse kinase. Under fed-batch conditions, the engineered strain BL21ΔxylAB/pE-mdlCxylBC&pA-adhPyjhG produced up to 3.92 g/L of BT from 20 g/L of xylose, corresponding to a molar yield of 27.7%. These results suggest that the engineered E. coli has a promising prospect for the large-scale production of BT

A Low-cost, High-impact Node Injection Approach for Attacking Social Network Alignment

Social network alignment (SNA) holds significant importance for various downstream applications, prompting numerous professionals to develop and share SNA tools. Unfortunately, these tools can be exploited by malicious actors to integrate sensitive user information, posing cybersecurity risks. While many researchers have explored attacking SNA (ASNA) through a network modification attack way, practical feasibility remains a challenge. This paper introduces a novel approach, the node injection attack. To overcome the problem of modeling and solving within a limited time and balancing costs and benefits, we propose a low-cost, high-impact node injection attack via dynamic programming (DPNIA) framework. DPNIA models ASNA as a problem of maximizing the number of confirmed incorrect correspondent node pairs who have a greater similarity scores than the pairs between existing nodes, making ASNA solvable. Meanwhile, it employs a cross-network evaluation method to identify node vulnerability, facilitating a progressive attack from easy to difficult. Additionally, it utilizes an optimal injection strategy searching method, based on dynamic programming, to determine which links should be added between injected nodes and existing nodes, thereby achieving a high impact for attack effectiveness at a low cost. Experiments on four real-world datasets consistently demonstrate that DPNIA consistently and significantly outperforms various attack baselines

The Generalized XOR Lemma

Abstract The XOR Lemma states that a mapping is regular or balanced if and only if all the linear combinations of the component functions of the mapping are balanced Boolean functions. The main contribution of this paper is to extend the XOR Lemma to more general cases where a mapping may not be necessarily regular. The extended XOR Lemma has applications in the design of substitution boxes or S-boxes used in secret key ciphers. It also has applications in the design of stream ciphers as well as one-way hash functions. Of independent interest is a new concept introduced in this paper that relates the regularity of a mapping to subspaces

On Cheating Immune Secret Sharing

The paper addresses the cheating prevention in secret sharing. We consider secret sharing with binary shares. The secret also is binary. This model allows us to use results and constructions from the well developed theory of cryptographically strong boolean functions. In particular, we prove that for given secret sharing, the average cheating probability over all cheating vectors and all original vectors, i.e., 1/n 2^n ∑ _c=1...n ∑ _α ∈V n ρ _c,α , denoted by øverlineρ , satisfies øverlineρ ≥ \frac12 , and the equality holds if and only if ρ _c,α satisfies ρ _c,α = \frac12 for every cheating vector δ _c and every original vector α . In this case the secret sharing is said to be cheating immune. We further establish a relationship between cheating-immune secret sharing and cryptographic criteria of boolean functions.This enables us to construct cheating-immune secret sharing