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The purpose of this paper is to explore the factors that affect the compactness of the mud filter cake, so as to prepare diaphragm wall slurry with good uniformity, small filtration loss and excellent recycling performance.

In this paper, the thickness, filtration loss and slurry viscosity of the filter cake are used as the characterization methods. The effects of pore depth, slurry specific gravity, intercalated metal ions, bridging polymer and water-soluble polymer on the compactness of the filter cake were studied.

The experimental results showed that the slurry's own pressure (pore depth) and specific gravity have little influence on the compactness of the filter cake and K⁺ can be considered as an auxiliary filtration loss reduction factor. Both the sulfonate copolymer and the potassium polyacrylate particle can significantly reduce the filtration loss of the slurry, which can effectively improve the filter cake compactness. Moreover, the composite application of potassium polyacrylate particles in the sizes of 80–100 and 150–200 meshes can exhibit a better filter cake compaction effect.

It solves the problems of high pulping cost, serious pollution of the environment, poor quality of filter cake formation and large filtration loss during the construction of the diaphragm wall, which improved the construction quality of the diaphragm wall.

A novel ternary flocculant was prepared by a simple compounding method to achieve efficient and rapid mud-water separation. This paper aims to discuss the possible mud-water separation mechanism.

This experimental study aims to investigate the effects of different types of flocculants on the separation of waste mud water and the degradation of flocculants in the supernatant. The flocculating component, the ratio of the flocculating accelerator to the flocculant and the addition amount of the novel ternary flocculant were optimized.

The experimental results show that the composition of the new ternary flocculant is cationic polyacrylamide (CP-02), grafted starch (GS-501) and flocculation sedimentation accelerator, the best effect, the mass ratio is 1:0.5: 0.75. According to 0.25:1 (volume ratio), the new ternary flocculant is pre-configured into a solution with a concentration of 3 kg/m³ to achieve efficient and rapid mud-water separation.

The new ternary flocculant is used for the separation of mud and water in the underground continuous wall waste mud, improving the level of civilized construction.

Cracks in the roof parapet wall and damage to the waterproofing membrane are the common defects of roof construction that require frequent maintenance. This paper seeks to review the common defects of roof construction of medium‐rise buildings in sub‐tropical climates.

The research reported was carried out by the survey and analysis of 20 case study buildings. The modes of rooftop parapet wall dislocation are studied and the effects of thermal expansion and end conditions of the parapet wall on the damage to the waterproofing membrane are analysed.

Parapet wall dislocation failure is dependent on whether the ends are hinged or fixed. Failure usually leads to tearing of the waterproofing membrane.

Modification to the roof parapet wall design and to the selection of construction materials is suggested.

The modes of failure and proposed modification will be of interest to designers and those responsible for the maintenance of flat‐roofed buildings in sub‐tropical climates.

The purpose of this paper is to model a block-based inspection policy for a multi-component system with stochastic dependence. Some components may develop a hidden failure, an occurrence of which neither stops the system nor accelerates the other components’ deterioration. On the other hand, other components may experience three states: healthy, defective and revealed failures. Any revealed failure of each component not only stops the system but also generates a shock to all the other ones, which increases their occurrence rate of hidden, defect and revealed failures.

A block-based inspection policy is considered to take advantage of economic dependence as follows. In addition to the periodic inspections, the system is also inspected at revealed failures’ moments of each component to detect and fix both defects and hidden failures on all the other components. To calculate the expected total cost, the recursive equations for the required expected values is first mathematically derived. Then, due to computational complexity, an efficient Monte Carlo simulation algorithm is designed to calculate the expected values.

The proposed approach is illustrated through a numerical example, and the optimal periodic inspection interval over a finite time horizon is obtained via minimization of the expected total cost. Finally, the correctness of the results is validated by conducting sensitivity analysis.

Planning an appropriate inspection policy over a finite time horizon becomes more complicated when considering a multi-component system because different units may experience different failure modes with stochastic dependence.

The notion of sustainability broadly builds upon the development of the present without hampering the needs of the future generation. Accordingly, the contemporary development programmes, in general, emphasise on minimising the adverse bearings of climate change and arresting the irreversible ecological degradation following the implementation of the growth-oriented economic models. While such idea of sustainable development is expected to be applied across different sectors, the traditional urban development projects such as the Integrated Development of Small and Medium Towns (IDSMT) (1979), the Mega-City Scheme (1993), and the Jawaharlal Nehru National Urban Renewal Mission (JNNURM) (2005) focussed mainly on physical infrastructure with inadequate emphasis on the ecological aspects and sustainability. However, with the experiences of globalisation and the negative impact of changing climate, the recent urban development initiatives across the world have gone through considerable redesigning, and the idea of eco-city, compact city, sustainable city, etc., have taken the central place in the project proposals. In this connection, the Smart City Mission (SCM) (2015) of the Government of India has emerged as an important initiative to facilitate improvement in the standard of living along with economic growth through the development of urban infrastructure and integration with intelligent technologies. This chapter attempts to understand how the projects under the SCM have incorporated various ecological aspects to transform the cities into liveable and sustainable ones for the future generation. Using secondary data and carrying out a comparative analysis of selected smart city proposals, this chapter finds that there is still a lack of adequate emphasis on ecological sustainability in many smart city proposals. This chapter suggests revisiting the smart city proposals, and initiatives should be made towards the development of urban areas in a sustainable way.

The study aims to determine an efficiency of external magnetic field on the bacteria surrounded by thousands of magnetic magnetite nanoparticles. The interstitial nanoliquid in which an artificial bacteria swims in biological cell is utilized with variable thermal conductivity. Two dimensions unsteady motion of second grade fluid are considered. The stretching wall is taken as a curved surface pattern.

The mathematical results have been obtained by Chebyshev pseudospectral method.

The impact of the various governing parameters is described by numerical tables and diagrams. It is proven that the pure blood velocity curves are higher when compared with the magnetite/blood. It is demonstrated from clinical disease that dangerous tumors show diminished blood flow. This study concludes that the blood velocity profile increases by increasing the values of fluid parameters. This implies that the medication conveyance therapy lessens the tumor volume and helps in annihilating malignancy cells. The blood temperature distribution raises as the magnetite nanoparticles concentration increases. Consequently, the physical properties of the blood can be enhanced by immersing the magnetite nanoparticles. Further, the present outcomes cleared the thermal conductivity as, a variable function of the temperature, has an important role to enhance the heat transfer rate.

To the best of authors’ knowledge, this study is reported for the first time.

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

The system encountering dormant failure subject to sequential inspections is modeled and the emphasis is made on determining the availability and long-run average cost rate for the model. The derived results are then utilized to obtain the optimal inspection period minimizing the cost.

Explicitly, a system with a functional and a failed state is taken into account. Inspections are performed to reveal the dormant failures and are assumed to be carried out at time T, T + aT, T + aT+a² T, … where 0 < a = 1 in each cycle. Perfect repairs taking random times are performed if the system is found in a failed state during any inspection.

Some theorems on the point availability, limiting availability and long-run average cost rate are obtained in the study. An illustration is shown to explain the results obtained in the proposed work. The effect of inspection time on the availability and cost rate is also analyzed graphically.

The availability and cost rate for a system with dormant failure under a sequential inspection policy are figured out unlike previous research.