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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.

EC-135P2+ helicopters operated by Polish Medical Air Rescue are highly exposed to environmental particles entering engines when performing helicopter emergency medical services. This paper aims to assess the effectiveness of inlet barrier filters installed to protect the engines, including their impact on maintenance.

The organisation adopted a comprehensive set of measures to predict and limit the impact of dust ingestion including visual inspections, health management and engine trend monitoring based on ground power checks’ (GPC) results. Three alternative particle separation solutions were considered. Finally, helicopter inlets were modified to allow the selected filter system to be installed, which reduced the number of particles ingested by the engine and prevented from premature overhauls.

The analyses carried out enabled not only the selection of the optimal filtration solution and its seamless implementation into the fleet but also confirmed its efficiency. After installing the filters, engines’ lifetime is extended from 500 to 4,500 flight hours while operating costs and the number of maintenance tasks was reduced significantly.

Lessons learned from operational experience show that a well-matched particle separation system can mitigate accelerated engine deterioration even if the platform is continuously exposed to environmental particles. The remaining useful life of engines can be predicted using performance models and data from GPC.

This study aims to investigate how mature born global firms create value for customers to achieve continued international growth.

The study employs a case study approach to investigate the under-researched area of how mature born globals create value for customers and, by doing so, contribute to their continued international growth. This in-depth examination of how three born globals developed over time uses interviews, observation and secondary data.

The findings indicate that the entrepreneurs of born global firms, that continued to grow, created a culture in the early stages that supported value creation for foreign customers. These firms have built a competitive position by developing international niche products. They have also implemented a combination of proactive and reactive market orientation to facilitate the creation and delivery of value to customers. To maintain growth, they further invest the revenues earned on additional international marketing activities and continuously enhance their focal products.

The study relies on three cases. We therefore recommend that future studies extend the scope of the research to several companies in various industries and countries, in which the theoretical arguments can be applied. In addition, further studies that test the propositions developed in this study, in different contexts, are highly recommended.

To gain international growth, managers should create an organizational culture that facilitates satisfying international customer needs. Firms should continuously invest in sales and market development (e.g. social media marketing, personal selling) and undertake technology development of niche rather than new products. To achieve international growth, managers need to standardize part of the offer to achieve economies of scale and adapt the other part to international customers' needs.

Research on born globals has focused on the early stages of their internationalization processes, while largely neglecting the later stages (mature born globals) or the factors that lead to continued international growth. To address this gap, this study explores what happens when born globals ‘grow up’. This study contributes to the literature by capturing the factors and processes underlying how mature born globals create value for customers, for international growth. In particular, the study shows that the culture and strategies developed in the born globals' early stages also lead to international growth in later stages. The mature born globals have also invested in niche products, brand building, and effective market channels and adopted a combination of proactive and reactive market orientations.

The percentage of dairy cows managed in grazing systems in Northwest Europe is on the decline, even though pasturing is perceived favourably as enhancing the health and welfare of dairy cows. With consumers turning away from intensively produced food, developing the pasture-raised milk market could encourage farmers to continue keeping their cows on pastures. To provide insights for expanding this specialty milk market, the purpose of this paper is to, therefore, investigate the roles of personal, product-related, economic and social factors in purchasing pasture-raised milk.

Drivers of pasture-raised milk purchases are identified and the conceptual model is tested using structural equation modelling with data from a cross-sectional study among 917 German milk consumers.

Perceived price and availability barriers are the main consumption obstacles for pasture-raised milk. Besides increasing availability and reducing price premiums, processors should cater health and dietary conscious consumers by providing pasture-raised milk with unique and favourable product qualities, i.e. focussing on freshness, a rich taste or naturalness. Raising awareness for extensive husbandry systems may enhance pasture-raised milk purchases, while introducing a unified pasturing claim could help consumers to distinguish pasture-raised milk from conventional barn milk.

This study provides dairies and marketers with valuable insight about the factors driving pasture-raised milk purchases. This information is derived from a large sample with extensive regional coverage and will thus be useful in expanding this specialty milk market and in maintaining extensive dairy production.

Zinc‐wire Pistol. A new version of the Mark 30 heavy‐duty motorised pistol is being manufactured. Illustrated on this page is a unit in operation spraying 5‐mm.‐diam. zinc wire at the rate of 132 lb./hr. The two spraying heads are fitted with double air caps to ensure a superfine coating even at a high rate of spraying. The heads can be angled to provide adjustment of the focal point.

During drilling in coal mines, sticking of drill rod (referred to as SDR in this work) is a potential threat to underground safety. However, no practical measures to deter SDR have been developed yet. The purpose of this study is to develop an anti-SDR strategy using proportional-integral-derivative (PID) and compliance control (PIDC). The proposed strategy is compatible with the drilling process currently used in underground coal mines using drill rigs. Therefore, this study aims to contribute to the PIDC strategy for solving SDR.

A hydraulic circuit to reduce SDR was built based on a load-independent flow distribution system, a PID controller was designed to control the inlet hydraulic pressure of the rotation motor and a typical compliance control approach was adopted to control the feed force and displacement. Moreover, the weight and optimal combination of the alternative admittance control parameters for the feed cylinder were obtained by adopting the orthogonal experiment approach. Furthermore, a fuzzy admittance control approach was proposed to control the feed displacement. Experiments were conducted to test the effectiveness of the proposed method.

The experimental results indicated that the PIDC strategy was appropriate and effective for controlling the rotation motor and feed cylinder; thus, the proposed method significantly reduces the SDR during drilling operations in underground coal mines.

As the PIDC strategy solves the SDR problem in underground coal mines, it greatly improves the safety of coal mine operation and decreases the power cost. Consequently, it brings the considerable benefits of coal mine production and vast application prospects in other corresponding fields. Actual drilling conditions are difficult to accurately simulate in a laboratory; thus, for future work, drilling experiments can be conducted in actual underground coal mines.

The PIDC-based anti-SDR strategy proposed in this study satisfactorily controls the rotation motor and feed cylinder and facilitates the feed and rotation movements. Furthermore, the tangible novelty of this study results is that it improves the frequency response of the entire drilling system. The drilling process with PIDC decreased the occurrence of SDR by 50%; therefore, the anti-SDR strategy can significantly improve the safety and efficiency of underground coal mining.

This paper aims to discuss the development of a software tool UniverFilter™ which is capable of geometrical modelling of 3D woven fabrics, interfacing with computational fluid dynamics tools to numerically determine the fluid (and more specifically liquid) flow path and simulating the filtration process by introducing particles of various shapes and sizes.

The method employed in creating the software tool is based on geometrical modelling of the single‐layer woven fabric with monofilament yarns, numerical analysis of the fluid‐flow problem, and mathematical modelling of the forces exerted on particles to accurately predict the settlement of such particles on the fabric. In the case of particle motion, a Lagrangian approach is used.

Creation of a software tool capable of simulation and modelling the filtration process through woven fabrics is the primary achievement. The effect of geometrical parameters of the woven fabric on fluid flow utilizing the results from fluid pressure and fluid velocity on the fabric show that the fluid flow is significantly influenced in the interstices and chamber downstream by the fabric. Fluid‐flow resistance and pressure loss are obtained from the results of fluid velocity and pressure. The results from the fluid pressure on the fabric could also be employed to more accurately predict how pore shapes and sizes are transformed.

Creation of a modelling tool for filtration through woven fabric media. This software is the foundation of establishing a standalone tool with the capability to design, test and improve fabric filter design for more efficient filtration properties.

The utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current research aims to design and develop a novel co-generation system to address the electricity and potable water needs of rural areas.

The cogeneration system mainly consists of a solar parabolic dish concentrator (SPDC) system with a concentrated photo-voltaic module at the receiver for electricity generation. It is further integrated with a low-temperature thermal desalination (LTTD) system for generating potable water. Also, a novel corn cob filtration system is introduced for the pre-treatment to reduce the salt content in seawater before circulating it into the receiver of the SPDC system. The designed novel co-generation system has been numerically and experimentally tested to analyse the performance at Karaikal, U.T. of Puducherry, India.

Because of the pre-treatment with a corn cob, the scale formation in the pipes of the SPDC system is significantly reduced, which enhances the efficiency of the system. It is observed that the conductivity, pH and TDS of seawater are reduced significantly after the pre-treatment by the corncob filtration system. Also, the integrated system is capable of generating 6–8 litres of potable water per day.

The integration of the corncob filtration system reduced the scaling formation compared to the general circulation of water in the hoses. Also, the integrated SPDC and LTTD systems are comparatively economical to generate higher yields of clean water than solar stills.

Filter media used for full‐flow filtration are made of paper, woven wire cloth and monofilament fabrics. The main characteristic of paper is a high retention rate of small particles. An absolute filter fineness is difficult to guarantee. Woven filter cloth can today be produced within a mesh tolerance less than 5 per cent. This makes it possible to remove excessively large particle sizes in the oil. It is possible to range lubricating oil systems into classes depending on the increasing amounts of solid matter. For each stage of contamination exists an optimal filter and filter arrangement.