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The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar cracks and reduce the water absorption of mortar after healing.

Bacillus pseudofirmus spores were immobilized with EP particles as self-healing agents. The effects of adding self-healing agents on the compressive strength of mortar specimens were observed. The ability of mortar specimens to heal cracks was evaluated using crack microscopic observation and water absorption experiments. The filler at the cracks was microscopically analyzed by scanning electron microscope and X-ray diffraction experiments.

First, the internal curing effect of EP promotes the hydration of cement in mortar, which generates more amount and denser crystal structure of Ca(OH)2 at mortar cracks and improves the self-healing ability of mortar. Second, the self-healing ability of mortar improves with the increase of self-healing agent admixture. Adding a self-healing agent of high admixture makes the planar undulation of calcite crystal accumulation at mortar cracks more significant. Finally, the initial crack widths that can be completely healed by adding EP and self-healing agents to the mortar are 200 µm and 600 µm, respectively.

The innovation points of this study are as follows. (1) The mechanism of the internal curing effect of EP particles on the self-healing ability of mortar cracks was revealed by crack microscopic observation tests and microscopic experiments. (2) The effect of different self-healing agent amounts on the self-healing ability of mortar cracks has been studied. (3) The effects of EP particles and self-healing agents on healing different initial widths were elucidated by crack microscopic observation tests.

This study aims to investigate the microtopography transformation at a low-speed heavy-load interface with the lubrication of powder particles and its nonlinear friction effect on the sliding pair in contact.

Based on the universal mechanical tester (UMT) tribometer and VK shape-measuring laser microscope, comparative friction experiments were conducted with graphite powder lubrication. The friction coefficient with nonlinear fluctuations and the three-dimensional morphology of the boundary layer at the interface were observed and analyzed under different operating conditions. The effects on lubrication mechanisms and frictional nonlinearity at the sliding pair were focused on under different surface roughness and powder layer thickness conditions.

At a certain external load and sliding speed, the initial specimen surface with an appropriate initial roughness and powder thickness can store and bond the powder lubricant to form a boundary film readily. The relatively flat and firm boundary layer of powder at the microscopic interface can reduce the coefficient of friction and suppress its nonlinear fluctuation effectively. Therefore, proper surface roughness and powder layer thickness are beneficial to the graphite lubrication and stability maintenance of a friction pair.

This research is conducive to developing a deep understanding of the microtopography transformation with frictional nonlinearity at a low-speed heavy-load interface with graphite powder lubrication.

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.

The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.

The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.

This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.

The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.

The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.

Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.

Two effects simultaneously shape the future soybean meal (SBM) demand in China: the income effect on meat consumption and the transition effect due to commercial feed usage in animal production. The income effect has been studied intensively in previous research and results in rapidly growing animal product consumption. The commercial feed transition effect, however, is not well understood. The accurate forecast of SBM demand requires an integration of both effects. This study aims to contribute to the commodity forecast literature: by estimating the non-commercial to commercial feed effect and then comparing to the income effect.

This research addresses the gap in the literature by considering the diffusion path of commercial feeding technology when forecasting China's future SBM demand. The paper addresses the following five objectives to accomplish this goal. Objective 1: estimate income elasticity of demand for meat; Objective 2: estimate the current commercial feeding gap; Objective 3: analyze the reasons for low SBM feeding ratios; Objective 4: estimate future SBM feeding ratios; Objective 5: forecast future soybean demand in China.

China needs 33 years from 2009 to achieve the SBM feeding ratio of 98 percent. The difference in future derived demand for SBM mainly comes from the transition effect of animal production industry in China. The income effect only contributes on average 2.1 percent of the theoretical SBM consumption quantity over the next 20 years. The feeding technology diffusion effect, however, causes an additional 3.6 percent annual compound growth rate on the demand increase for SBM over the same time periods. The livestock industry's transition effect is roughly equivalent to 1.5 times the income effect.

Policy makers, industry managers, and analysts will now have not only a more accurate estimate of future SBM demand, but also a better understanding of the structural components of that estimation. In particular, the role of commercial feed adoption is explicitly estimated.

This research is the first to estimate the effect of the shift from non-commercial to commercial feeding systems on overall SBM demand. The results show that not accounting for the diffusion of new commercial feeding technology creates under the estimates of future SBM demand.

The changing environment and competitive market forces have brought many changes in the business sector that have put organisations under immense pressure. The use of psychometric assessments and behavioural profiling help organisations to determine individuals' abilities, aptitudes, personality traits, values and factors which intrinsically motivate them and assist in bringing the right people on board who fit well within the organisational culture and can contribute towards the performance goals. Although behavioural profiling and psychometric assessments are accepted worldwide, however, developing countries particularly the public sector still relies on conventional recruitment methods and the adaptation of contemporary behavioural profiling and psychometric assessments is a challenge. Therefore, this chapter evaluates how the adaptation of behavioural profiling and psychometric assessments in the civil service exams in developing countries can improve the selection process and ultimately can help to improve the quality of public services, capacity building and achieving sustainability goals.

Although an important facet of modernist architecture in which function plays a prominent role, building flexibility is not entirely a new concept. Its relevance transcends generations, allowing space and structure to evolve through time. This paper investigates the relationship among main building structures, infill elements, and space by studying examples in ancient Chinese architecture. It reveals the role of building owners, users, and craftsmen from a survey of historical documentation. In studying these examples, it is concluded that craftsmen in ancient China were involved not only during the construction phase but throughout the period of use as well. Thus, in select cases, the relationship between craftsmen and owners or users had been preserved for generations. Finally, this paper suggests potential strategies for the building industry and technology in the move towards sustainable development.

Pipeline robots are often used in pipeline non-destructive testing. Given the need for long-range in-pipe inspections, this study aims to develop a wireless in-pipe inspection robot for image acquisition.

In this paper, an in-pipe robot with a new mechanical system is proposed. This system combines a three-arm load-bearing structure with spring sleeves and a half-umbrella diametric change structure, which can ensure the stability of the camera when acquiring images while maintaining the robot’s flexibility. In addition, data were transmitted wirelessly via a system that uses a 433 MHz ultra-high frequency and wireless local-area network–based image transmission system. Software and practical tests were conducted to verify the robot’s design. A preliminary examination of the robot’s cruising range was also conducted.

The feasibility of the robot was demonstrated using CATIA V5 and MSC ADAMS software. The simulation results showed that the centre of mass of the robot remained in a stable position and that it could function in a simulated pipeline network. In the practical test, the prototype functioned stably, correctly executed remote instructions and transmitted in near real-time its location, battery voltage and the captured images. Additionally, the tests demonstrated that the robot could successfully pass through the bends in a 200-mm-wide pipe at any angle between 0° and 90°. In actual wireless network conditions, the electrical system functioned for 44.7 consecutive minutes.

A wheeled wireless robot adopts a new mechanical system. For inspections of plastic pipelines, the robot can adapt to pipes with diameters of 150–210 mm and has the potential for practical applications.

The service performance for colored asphalt pavement is inevitably affected by the addition of different colorants, especially the challenge of low temperature environment in cold regions. Therefore, the purpose of study is to explore the effects of different colorants on the service performance for colored asphalt pavement and to provide a foundation for improving the applicability of colored asphalt pavement in cold regions.

In the study, three kinds of colorants (iron oxide red, iron oxide yellow, iron oxide green) were used to compare the influence of different colorants amounts and different colorants kinds on the service performance for colored asphalt pavement in cold regions. According to the characteristics of low temperature in cold regions, the effects of different colorants on the low temperature performance for colored asphalt pavement were studied.

The study shows that different colorants have different effects on the service performance of colored asphalt pavement. The high temperature performance increases with the increase of the colorants amount, but the low temperature performance is opposite. Additionally, the yellow colored asphalt pavement has more advantages of low temperature adaptation than the red and green colored asphalt pavement.

The study results provide a certain theoretical foundation for the application of colored asphalt pavement in cold regions and have certain value and significance for the further development of colored asphalt pavement.

Most projects are facing delays, and accelerating the pace of project progress is a necessity. Project managers are responsible for completing the project on time with minimum cost and with maximum quality. This study provides a trade-off between time, cost, and quality objectives to optimize project scheduling.

The current paper presents a new resource-constrained multi-mode time–cost–quality trade-off project scheduling model with lags under finish-to-start relations. To be more realistic, crashing and overlapping techniques are utilized. To handle uncertainty, which is a source of project complexity, interval-valued fuzzy sets are adopted on several parameters. In addition, a new hybrid solution approach is developed to cope with interval-valued fuzzy mathematical model that is based on different alpha-levels and compensatory methods. To find the compatible solution among conflicting objectives, an arithmetical average method is provided as a compensatory approach.

The interval-valued fuzzy sets approach proposed in this paper is denoted to be scalable, efficient, generalizable and practical in project environments. The results demonstrated that the crashing and overlapping techniques improve time–cost–quality trade-off project scheduling model. Also, interval-valued fuzzy sets can properly manage expressions of the uncertainty of projects which are realistic and practical. The proposed mathematical model is validated by solving a medium-sized dataset an adopted case study. In addition, with a sensitivity analysis approach, the solutions are compared and the model performance is confirmed.

This paper introduces a new continuous-based, resource-constrained, and multi-mode model with crashing and overlapping techniques simultaneously. In addition, a new hybrid compensatory solution approach is extended based on different alpha-levels to handle interval-valued fuzzy multi-objective mathematical model of project scheduling with influential uncertain parameters.

The purpose of this paper is to investigate the implications of the China’s rising meat demand and industrialization of the livestock sector for the vegetable oil market.

An equilibrium displacement model is constructed to analyze the interactions between meat consumption and vegetable oil market through the development of livestock sector modernization. Parameters derived from the 2006 to 2009 data are first used to produce the counterfactual growth rate of the non-soybean vegetable oil to validate the model. Then the authors use the second set of parameters derived from the 2010 to 2013 data to forecast the changes in the vegetable oil market in China.

Soybean oil, as a co-product of soybean processing, tends to crowd out other vegetable oils. In particular, the authors find that the market for non-soybean vegetable oils may shrink as long as the rapid industrialization pace above 10 percent within China’s livestock sector continues. Although their production takes up only 8.5 percent of all agricultural lands in China, oil crops remain as important cash crops for farmers contributing over 10 percent to the overall farm income in some provinces. The authors’ analysis suggests that stakeholders in these regions should closely monitor the structural changes within the livestock sector and consider the information for crop selection.

The authors’ analysis contributes to the literature on China’s meat demand by highlighting its implications for other agricultural markets involved in the food system.