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At present, the enzyme washing process is widely used in hemp garment in the industry. However, it has many disadvantages. First, it is inefficient and labor-intensive, which can only be produced in small quantities and will take much time for workers to check. Second, its cost is high. The strength loss of the garment is up to 20 percent, with a bad damage. Presently, the enzyme washing process of the gray fabric is not industrialized. The purpose of this paper is to obtain a stable and efficient process for the enzyme washing of the gray fabric.

The whiteness, weight loss rate, strength, dyeing property and fabric style of enzyme washed gray fabrics were studied.

The results showed that the enzyme treated fabric has soft handle, smooth surface, good elasticity and high levelness, as well as low strength reduction rate under the optimized condition of bath ratio of 1:12, cellulase dosage of 0.3 percent, pectinase dosage of 1 g/L, treatment temperature of 55°C, treatment time of 80 min and pH of 6.

First, the process is environment friendly, green and sustainable and, second, it will make the industrialization of the enzyme washing process of gray fabrics, with a high commercial value.

This study aims to build a global environmental quality protection convention to jointly address the problems of environmental pollution governance worldwide.

From the perspective of environmental pollution of the air, ocean, forest, water and solid waste, the authors summarize the main important measures and mechanisms of environmental pollution governance in various countries.

The results indicate that management research on biodiversity and natural resources must be strengthened, the relationship between economic development and environmental quality management needs to be balanced, the comparative study of domestic and international environmental governance theories and practices should be strengthened, empirical and applied research on environmental governance needs to be focused on, and complete system research on environmental governance and management should be explored. In the future, further strengthening environmental awareness, addressing environmental pollution and managing environmental quality are necessary.

The environment is the foundation of human survival and development. With the development of economy, contradictions between human and natural environment (e.g. air, ocean, forest and water) have become prominent. Environmental pollution governance cannot only help address existing environmental problems but also solve economic problems of various countries. The prerequisite for sustainable development is to lay a solid foundation for the coordinated development of economic growth and pollution management.

Laser melting deposition (LMD) is an advanced additive manufacturing (AM) technology without powder waste, and nickel-based alloys with different Nb contents were created one-time by adjusting the ratio of mixed powders via a dual-feed system. Here, the authors provide a systematic report on the effects of the Nb content on the microstructure, Laves phase segregation and mechanical properties of as-received LMD nickel-based alloys. The effects of the Nb content on the microstructure, precipitation evolution and mechanical properties of the subsequent heat-treated LMD samples are also discussed in this paper.

Thus, the present research aims to obtain a better understanding of the effect of Nb content on the microstructural and mechanical properties of the as-received LMD Inconel 718 alloys through high-throughput sample fabrication. The microstructures were characterized by scanning electron microscopy and energy-dispersive spectroscopy, electron back-scattered diffraction and transmission electron microscopy methods. The mechanical properties were obtained from compressive tests and nano-indentation tests. Electrochemical tests, including electrochemical impedance spectroscopy and potentiodynamic polarizations, were carried out to evaluate the durability of the Inconel 718 alloys. Results can provide a factual basis for future applications of the functionally graded by AM technology.

The grain size of the as-received LMD Inconel 718 alloys decreased with the Nb content. The Laves phase distribution at the macro level was relatively uniform and the Laves phase exhibited a 1.5-fold nano-hardness compared with the matrix. The strength improvement for the as-received LMD Inconel 718 alloys with Nb content was attributed to grain refinement and enhancement of the Laves phase in terms of both hardness and content. Meanwhile, the corrosion resistance increased with the increase of the Nb content, especially for the pitting potential, which was attributed to the optimization of carbide precipitates due to the strong affinity between niobium and carbon.

The results provide a factual basis for the Nb content effect in LMD nickel-based alloys, and this method can greatly promote the development of new materials. The authors believe that this study makes a significant contribution to the literature and is suitable for publication.

The purpose of this paper is to combine the uncertain methods of type-2 fuzzy sets and data envelopment analysis (DEA) evaluation model together. A new type-2 fuzzy DEA efficiency assessment method is established. Then the proposed procedure is applied to the poverty alleviation problem.

The research method is the DEA model, which is an effective method for efficiency assessment of social–economic systems. Considering the existence of the same efficiency values that cannot be ranked in the proposed DEA model, the balance index is introduced to solve the ranking problem of decision-making units effectively.

The results show that the proposed method can not only measure the efficiency of the existence of uncertain information but also deal with the ranking of multiple efficient decision-making units.

This paper selects type-2 fuzzy DEA model to express a lot of uncertain information in efficiency evaluation problems. We use the parameter decomposition method of type-2 fuzzy programming or the type-2 expectation values indirectly. The balance index is proposed to further distinguish the multiple effective decision-making units. Furthermore, this paper selects rural poverty alleviation in Hainan Province as a case study to verify the feasibility of the method. The relative efficiency values in different years are calculated and analyzed.

This paper aims to clarify the effects of metallic nanoparticles (NPs) additives and room temperature ionic liquids (ILs) on the tribological performance of electric contacts.

Tribological properties of copper (Cu) and silver (Ag) NPs as lubricant additives in different lubricants of ILs or polyalphaolefin (PAO) oils under applied electric currents were investigated. After tribological tests, morphologies of worn surfaces were observed; meanwhile, lubrication and anti-wear properties were analyzed.

The mixture solution of the IL and Cu NPs showed desirable lubrication and anti-wear properties due to the reduction of electrocorrosion and the enhancement of rolling effects of particles in the contact region. The anti-wear performance of Cu NPs is better than that of Ag NPs due to the difference in the particle size. The PAO oil with the Cu NPs additives showed poor lubrication properties due to the low solubility of the particles in the oil. When the direction of applied current was changed, the friction of the lubricant with better conductivity was more stable in the variation trend.

This paper begins with a study of tribological properties of Cu and Ag NPs as lubricant additives in different lubricants of IL or PAO oils under applied electric currents. The authors then propose several methods and possible solutions which could be implemented to improve the tribological performance of electric contacts.

This paper investigates the dynamic pricing strategy of a firm for the successive-generation products under the conditions of the limited trade-in duration and strategic customers. Further, it explores the effect of a limited trade-in duration on the choice of the myopic and strategic customers, besides the optimal dynamic pricing and trade-in strategy of the firm.

Based on the choice behavior of the myopic and strategic customers, the authors have developed a two-period game-theoretic analytical model to decide the optimal retail prices of the successive-generation products and the optimal trade-in rebate when the firm adopts a dynamic pricing strategy and then investigate three extensions of the basic model to discuss the change in the results owing to the relaxation of certain conditions.

The authors find from the results that, in terms of profit maximization, it is better to extend the limited trade-in duration, and hence, the firm should implement a dynamic pricing strategy. However, in the situation of using a static pricing strategy, the firm should extend the limited trade-in duration only if the incremental value of the new generation products is below a certain threshold. Moreover, the firm should use a dual rollover strategy instead of a single rollover one. If all customers in the market are myopic, then the firm should also extend the limited trade-in duration.

This study mainly discusses the impact of limited trade-in duration on the firm's dynamic pricing strategy when facing strategic customers, which provides several directions for future research. First, if the government offers subsidies to consumers, how will strategic consumers make purchase decisions? How would the enterprise make its pricing decision? Second, when asymmetric information exists between consumers and firms, how will it affect consumers' choice behavior and firms' pricing decisions? All these issues are worth exploring in the future.

These results offer certain managerial insights for the firm in the decision making on pricing within the trade-in program.

This is the first work to study the dynamic pricing strategy of the firm for the successive-generation products under the conditions of the limited trade-in duration and strategic customers. Further, this work discusses the changes in results owing to the relaxation of certain conditions.

The purpose of this paper is to upgrade the collaborative emergency ability of government in the tier of towns, realizing emergency resource share, emergency cost reduction and emergency efficiency improving. This paper mainly aims to solve the problem of forecasting the natural disaster happening year of every township collaborative region in Fangshan District.

First, classify the townships into five collaborative regions through grey clustering. Second, set up a grey disaster forecast model for the whole Fangshan District according the annals of disaster from 1985 to 2012, and forecast the disaster grade. Third, build a grey disaster forecast model for the collaborative regions after constructing the buffer operators of catastrophic sequence according the annals of disaster from 1949 to 2012.

The authors forecasted the happening year and flood grade of future disaster for the whole Fangshan District. The accurate degrees of both flood and drought year model are greater than 90 per cent. The accurate degree of insects calamity year is a little low, but the relative errors are all lower than 3 per cent in recent continuous three times, so in the whole, it can be used. For the collaborative regions, the authors forecasted the future disaster years of them. The accuracy rate of every model is greater than 90 per cent. The result shows that the forecast errors are acceptable.

In the models, for the purpose of good accuracy, the authors used different initial data. For example, in the forecast model for whole Fangshan District disaster year, the authors used the data from 1985 to 2012, while in the forecast model for the disaster grade of it, the authors used the data from 1949 to 2012. In the disaster year forecast model for collaborative region, the authors also used the data from 1949 to 2012. If the authors can find a model that has high accuracy rate by using all the date information, it will be better.

Township is the most basic level of government organization in China, researching on collaborative emergency in township will do help to take targeted precautions measures against calamity according to the characteristic there. At the same time realizing emergency cost reduction and emergency efficiency improving based on the advantages of emergency resource share, short rescue distance, little effects of communication destruction.

Because of the stochastic occurring of disasters, it is very important to forecast the happening time of disasters accurately. This paper forecasted the natural disaster happening time of Fangshan District through grey catastrophic model, aimed at giving decision support to related department and strengthen the disaster prevention power targetedly.

It is well known that the greater the system, the steadier it is, and the easier to forecast it. Fangshan District, Beijing, is a medium-sized and small system in regional research, while townships are small systems. It is rarely a big challenge for the authors to forecast the disaster years in Fangshan and its collaborative townships. In this paper, the authors used grey system model and Markov transfer matrix in forecasting the disaster years and the disaster grade of flood in Fangshan District. All of them are new trying to using grey system theory in disaster forecast for Fangshan District, Beijing.

As China's educational policy and reforms continue to evolve and adjust to shifting social, economic, and political conditions, this chapter provides a template for conceptually framing education research on and in China. To do so this chapter first identifies focus areas in comparative education research related to China, which reflect researcher perspective, perceived advantage, and demonstrated resistance to these educational policy reforms. The authors develop a conceptual framework for comparatively understanding education research on and in China, which focuses on the intersection of comparative education themes, institutional change agents or methods, and Chinese educational reform topics. This conceptual framework specifically accounts for overlap, complexity, and the evolving nature of educational policy reform in China. This chapter concludes by emphasizing the importance of comparative education researchers, national policymakers, and consumers of the research using new data and methods as they become available to continue to revise understandings of Chinese educational policy and reform.

Chentong Chen is an undergraduate at Nanjing Normal University studying law and English. She has research interests in education policy, education assessment and evaluation, and child development. She is currently working on two research projects: policy issues related to the college entrance exam in China, and theories and practice of preschool assessment in the U.S.