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This paper aims to critically review the isolation and chemistry of plant pigments.

A literature survey from 1974 to 2022 was carried out and studied thoroughly. The authors reviewed literature in various areas such as isolation methods and catalytic properties of pigments.

With vast growing research in the field of catalytic activities of various pigments like chlorophyll, anthocyanin and flavonoids, there is still scope for further research for the pigments such as Lycopene, carotenoids and xanthophyll as there has not been any significant work in this area.

Plant pigments may be used as an ecofriendly catalyst for chemical reactions.

One can get the direction of pigment research.

Plant pigments are natural and ecofriendly catalyst which can reduce the pollution.

This is an original work. This paper precisely depicts the advantages as well as disadvantages of the isolation techniques of pigments. This study also presents the chemistry of plant pigments.

The purpose of this paper is to propose a novel strategy of optimal parameters configuration and placement for sensitive equipment.

In this study, clamped thin plate is considered as the foundation form, and a novel composite system is proposed based on the two-stage isolation system. By means of the theory of mechanical four-pole connection, the displacement amplitude transmissibility from the thin plate to precision equipment is derived. For the purpose of performing optimal design of the composite system, a novel multi-objective idea is presented. Multi-objective particle swarm optimization (MOPSO) algorithm is adopted as an optimization technique, which can achieve a global optimal solution (gbest), and selecting the desired solution from an equivalent Pareto set can be avoided. Maximum and variance of the four transmitted peak displacements are considered as the fitness functions simultaneously; the purpose is aimed at reducing the amplitude of the multi-peak isolation system, meanwhile pursuing a uniform vibration as far as possible. The optimization is mainly organized as a combination of parameter configuration and placement design, and the traversal search of discrete plate is performed in each iteration for the purpose of achieving the global optimum.

An important transmissibility based on the mechanical four-pole connection is derived, and a composite vibration isolation system is proposed, and a novel optimization problem is also defined here. This study reports a novel optimization strategy combined with artificial intelligence for parameters and placement design of precision equipment, which can promote the traditional view of two-stage vibration isolation.

Two-stage vibration isolation systems are widely applied to the vibration attenuation of precision equipment, but in these traditional designs, vibration participation of foundation is often ignored. In this paper, participation of foundation of equipment is considered, and a coherent new strategy for equipment isolation and foundation vibration is presented. This study shows a new vision of interdisciplinary including civil engineering, mechanical dynamics and computational science.

The fifth-generation technology 5G, the planned successor to 4G, is a new global standard for mobile networks that brings virtual to reality. 5G wireless technology enables the delivery of high speed, low latency, reliability, 100% coverage and availability to connect number of users as in massive IoT applications.

With expeditious development in wireless communication, the need for enhanced characteristic antenna design such as the size of the antenna, high data rate, demand in traffic, bandwidth, gain and efficiency increases. Various antenna designs are to be explored to meet the needs and achieve trade-offs between antenna size vs cost, high gain and efficiency vs less loss, high B.W and data rate with the selection of appropriate substrate materials and various gain & isolation enhancement techniques.

This paper thus gives scope for miniaturized MIMO antenna design for mobile applications at mm-wave frequency range.

This paper thus gives scope for miniaturized MIMO antenna design for mobile applications at mm-wave frequency range.

Introduces the special edition of EJM Vol. 14 No. 7, 1980, which is involved with use and potential use of multivariate techniques as an aid to marketing decision making. States that marketing practitioners seem less ready to join in the revolution and embrace the power of new techniques. Posits that management and researchers have a lack of communication problem which means a ‘switch‐off’ by management when information is presented in a form which is unfamiliar. Goes on to discuss marketing decision support systems and uses a figure for emphasis, using this as a critical appetiser for the techniques that follow. Closes by saying the techniques available form comprehensive sets of tools to aid the interpretation and presentation of that information.

This paper aims to present the design and implementation of a circularly polarized co-planar waveguide (CPW) fed wideband pie-shaped monopole antenna for multi-antenna techniques. Multi-antenna techniques are promising solutions for higher data rate and enhanced reliability of wireless applications. They find numerous applications in 4G/5G networks and in most wireless standards such as wireless local area networks (WLAN), wireless fidelity and worldwide interoperability for microwave access systems to enhance the channel capacity without additional spectrum by means of multi-path propagation techniques.

The antenna is designed to operate at three WLAN frequency bands of 4.8, 5.2 and 5.8 GHz. The measured 10 dB impedance bandwidth of the proposed antenna element is 1.2 GHz (24.23 per cent). The proposed CPW fed, pie-shaped monopole antenna has a gain of 5.4 dB and an efficiency of 72.8 per cent at 4.8 GHz.

To use the proposed antenna in a multi-antenna environment, the antennas have to be placed in a close proximity to each other. The close proximity introduces strong mutual coupling between the antennas, which in turn degrades the performance of multi-antenna systems. A multi-antenna system with two antenna elements has been constructed with an edge to edge spacing of 0.24 λ₀ (15 mm), and the mutual coupling level is −17 dB. To enhance the isolation between the antenna elements, a shorting pin-based interconnected semicircles enclosed decoupling structure is proposed, which improves the isolation by a factor of 12.67 dB at 4.8 GHz.

To validate the performance of the proposed multi-antenna in working environment, the performance metrics such as envelope correlation coefficient (ECC), diversity gain (DG) and total active reflection coefficient (TARC) are computed for the proposed multiple-input multiple-output (MIMO) antenna. The ECC value is 0.000366 at center frequency and below 0.09 for the entire operating bandwidth, which is well below the acceptable level of 0.5 as per 3GPP standard. The DG value lies above 9.5 dB for the entire operating bandwidths and it is well above the minimum value of 3 dB. The TARC values are calculated based on S parameters, and it proves that the proposed antenna a good candidate for the multi-antenna systems.

The purpose of this paper is to accomplish robust actuator fault isolation and identification for microsatellite attitude control systems (ACSs) subject to a series of space disturbance torques and gyro drifts.

For the satellite attitude dynamics with Lipschitz constraint, a multi-objective nonlinear unknown input observer (NUIO) is explored to accomplish robust actuator fault isolation based on a synthesis of H_inf techniques and regional pole assignment technique. Subsequently, a novel disturbance-decoupling learning observer (D²LO) is proposed to identify the isolated actuator fault accurately. Additionally, the design of the NUIO and the D²LO are reformulated into convex optimization problems involving linear matrix inequalities (LMIs), which can be readily solved using standard LMI tools.

The simulation studies on a microsatellite example are performed to prove the effectiveness and applicability of the proposed robust actuator fault isolation and identification methodologies.

This research includes implications for the enhancement of reliability and safety of on-orbit microsatellites.

This study proposes novel NUIO-based robust fault isolation and D²LO-based robust fault identification methodologies for spacecraft ACSs subject to a series of space disturbance torques and gyro drifts.

This paper aims to present an automated system that measures the volume of excavated soil in earthmoving operations. It focuses primarily on presenting the use of the radio frequency identification – real time location technology and image analysis techniques in isolation of stockpiles from their noisy backgrounds, extraction of their geometrical attributes and determination of their location.

An extensive literature review of image analysis techniques is performed to identify the ones most applicable in developing the proposed automated system. A set of techniques are selected and experimented to evaluate their effectiveness in the proposed application. A review of the state‐of‐the‐art distance measurement technologies is also conducted to identify the most suitable system to be used in the proposed system.

A set of image analysis techniques that positively contribute to the accuracy of the proposed system is identified. Geometrical attributes of stockpiles are automatically extracted for volume measurement purposes. The use of an affordable and reliable automated distance measurement tool is also suggested.

Although the proposed methodology is believed to be applicable to most configurations of stockpiles, it was tested on conical ones only.

The current practice of measuring the volume of excavated soil is time consuming and costly. Furthermore, it does not facilitate monitoring of excavation activities on close time intervals. The proposed system overcomes the problems associated with the current practice and provides an automated strategy that can be easily used by field personnel and/or home office management staff to closely monitor the progress of their earthmoving operations without physical human intervention.

Hazardous and radioactive wastes are routinely disposed of in shallow land disposal facilities at sites that have undergone environmental remediation. These residual contaminants, which remain on-site in these isolation facilities, continue to pose risks to humans and the environment and represent extremely long-term liabilities that require continuous management.

This paper draws upon the experiences generated from two federal programs established in response to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978 and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980. Operational issues arising at existing sites suggest that there is a need to better integrate the management functions at contaminant isolation facilities. To protect human health and safeguard the natural environment, more sustainable environmental protection systems are required for the long-term management of residual contaminants. A series of logic diagrams are introduced to improve the integration and management of remedial processes, engineered barriers and institutional controls. These institutional responsibilities need to be monitored and maintained by the appropriate site stewards to ensure continued system performance.

The purpose of this paper is to consider how ethics is currently taught to trainee auditors and to evaluate whether some ethical instruction techniques can be assessed as more effective than others.

Two separate cohorts of auditing students (262) provided responses to audit/accounting ethical scenarios. Each cohort was then subject to three separate ethics teaching techniques (either active or passive), from the two different teaching methodologies (active v. passive) over a semester. Their ethical attitudes to the scenarios were then re‐assessed and the teaching techniques evaluated.

Both methodologies were found to impact positively, as both cohorts selected more ethical responses to the scenarios post instruction. Some evidence of active techniques having more effect than passive techniques, on ethical decision making was revealed.

More research is needed into the impact of active and passive teaching methodologies on trainee auditors, in the ethics area.

Teaching ethics to the audit practitioners of tomorrow is critical. If the optimum mix of ethical teaching methodologies can be assessed, it will result in more effective ethical instruction. This study's results imply careful consideration must be taken in designing ethical training programs for trainee auditors.

Improvement in the ethical behaviour of auditors will provide more confidence for users of accounting information in the business environment.

This paper is original in that it evaluates the impact of a series of ethical instruction methods, as opposed to a single teaching method (the focus of many previous papers) on ethical training. The tentative finding of active methods proving more effective than passive methods is significant, and paves the way for future research.

This paper aims to present a triple-band monopole antenna design of 0.2-mm thickness with an overall dimension of 21 × 8 mm² for wireless local area network (WLAN)/worldwide interoperability for microwave access (WiMAX) multiple input and multiple output (MIMO) applications in the laptop computer.

It comprises three monopole radiating elements, namely, strip AD (inverted C), strip EG (inverted J) and strip FI (inverted U) along with two rectangular open-end tuning stubs, namely, “m” and “n” of size 1.5 × 0.9 mm² and 1.8 × 0.9 mm², respectively. The proposed structure is compact, cost-effective and easy to integrate inside the laptop computers.

This structure excites three WLAN (2.4/5.2/5.8 GHz) and three WiMAX (2.3/3.3/5.5 GHz) bands. The proposed antenna array elucidates that it has measured −10dB impedance bandwidth of 11.86 per cent (2.22-2.50) GHz in a lower band (f_l), 6.83 per cent (3.25-3.48) GHz in medium band (f_m) and 16.84 per cent (5.00-5.92) GHz in upper band (f_u). The measured gain and radiation efficiency are above 3.64dBi and 75 per cent, respectively, and isolation better than −20dB. The envelope correlation coefficient (ECC) is less than 0.004. The simulated and measured results are in good concurrence, which confirms the applicability of the proposed antenna array for MIMO applications in the laptop computer.

The proposed antenna is designed without using vias, reactive elements and matching circuits for excitation of WLAN/WiMAX bands in the laptop computers. The design also does not require any additional ground for mounting the antenna. Further, the antenna array, formed by using the same antenna design, does not need additional isolating elements and is designed in such a way that the system ground itself acts as an isolating element. The proposed antenna has a low profile and is ultra-thin, cost-effective and easy to manufacture and can be easily embedded inside the next-generation laptop computers.