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The paper aims to design a process to mechanize traditional chasing and repoussé which is the art of creating an artistic pattern on a sheet metal by making high and low points through utilization of hammer and chisel. In scientific literature, it is a kind of incremental sheet metal forming.

In the designed process, a magnetic actuator is used as a hammer which converts electric energy into kinetic reciprocal impact energy, and hammering sequence is completely controlled via the designed software. The sheet is bound not to move easily. Then, a hammering mechanism is connected to the numerical control machine. As the magnetic hammer is moved gradually along the defined path, the sheet is chased gradually by controlling the consecutive impacts. Different methods of test sheet entanglement are also discussed to reduce noise and undesired deformations of sheet, and indents are also clarified.

The designed mechanism enables the user to form desired art patterns faster with more precision via the automated process. The hammering sequence is controlled via computer successfully. The designed magnetic actuator could be commercialized easily. Experiments show that the pitch under sheet is the best. Typical art patterns are chased successfully.

In incremental sheet metal punching, there was no control on hammering sequence before. In this process, the designed magnetic hammer is quite controllable. Also, it is easily attached to the computerized numerical control (CNC) and is suitable for commercial use. Furthermore, the stuff under sheet was not taken into consideration before.

The objective of this work is to introduce a new method to carry out design optimization of a mechanical system for vibration and shock isolation, in particular, the viscous spring isolator mounting system for a forging hammer.

The system dynamics model for an isolated foundation and solution technique for obtaining system response under impact loads is introduced. A design optimization problem is formulated to minimize the maximum impact force transmissibility under design constraints, using stiffness and damping coefficients of the isolator, mass of the foundation block and support area of soil as design variables. A dedicated simulated annealing (SA) algorithm is applied to solve the optimization problem.

Viscous spring isolator mounting system, if properly designed, can considerably reduce shock and vibration transmission and the size of the foundation. The optimization leads to a mounting system with superior impact and vibration isolation capability over conventional designs. Sensitivity study and design optimization on a typical 3‐ton forging hammer has demonstrated the advantages of the new design method.

To further improve the accuracy of the design optimization, a more detailed system dynamics model might be introduced.

The work leads to a better design method for viscous spring isolator foundation systems.

This study forms the foundation for further research on design optimization of viscous spring isolator foundation systems, and contributes to the application of SA optimization technique to engineering design.

This paper reviews the most common building defects and techniques for their diagnosis. Problem areas are listed by their location within a structure and the information is presented in tabular form for easy reference. The first paper in this series — ‘Effective diagnosis of material problems and defects in building and construction’ — was published in Structural Survey Volume 4 Number 1. Part 3 will be an appraisal of better known in situ testing and NDT techniques featuring specific items of equipment.

The purpose of this study is to get benefits from manufacturing harmful wastes is by using them as a reinforcement with epoxy matrix composite materials to improve the damping characteristics in applications such as machine bases, rockets, satellites, missiles, navigation equipment and aircraft as large structures, and electronics as such small structures. Vibration causes damaging strains in these components.

By adding machining chips with weight percentages of 5, 10, 15 and 20 Wt.%, with three different chip lengths added for each percentage (0.6, 0.8 and 1.18 mm), the three-point bending and damping characteristics tests are utilized to examine how manufacturing waste impacts the mechanical properties. Following that, the optimal lengths and the chip-to-epoxy ratio are determined. The chip dispersion and homogeneity are assessed using a field emission scanning electron microscope.

Waste copper alloys can be used to enhance the vibration-dampening properties of epoxy resin. The interface and bonding between the resin and the chip are crucial for enhancing the damping capabilities of epoxy. Controlling the flexural modulus by altering the chip size and quantity can change the damping characteristics because the two variables are inversely related. The critical chip size is 0.8 mm, below which smaller chips cannot evenly transfer, and disperse the vibration force to the epoxy matrix and larger chips may shatter and fracture.

The main source of problems in machine tools, aircraft and vehicle manufacturing is vibrations generated in the structures. These components suffer harmful strains due to vibration. Damping can be added to these structures to get over these problems. The distribution of energy stored as a result of oscillatory mobility is known as damping. To optimize the serving lifetime of a dynamic suit, this is one of the most important design elements. The use of composites in construction is a modern method of improving a structure's damping capacity. Additionally, it has been demonstrated that composites offer better stiffness, strength, fatigue resistance and corrosion resistance. This research aims to reduce the vibration effect by using copper alloy wastes as dampers.

In developing countries such as India, it is common practice to use low‐quality building materials, the strength of such materials reduce with time, which affects the lifespan of buildings. The wind, rain, seepage, and surface runoff are other key factors responsible for building damage and exterior degradation. The increasing industrial growth in and around urban areas is responsible for increasing industrial and anthropogenic emissions that are found to accelerate degradation of the buildings that affects their physical appearance. In an area prone to natural hazards such as earthquakes, volcanoes, subsidence, floods, lightning, tornados, and cyclone/hurricanes, huge amounts of damage throughout the globe has been experienced. For the purpose of assuring safety due to natural hazards, it is necessary to monitor the damage for its existence, its location and extent. Undetected damage may potentially lead to risk of vulnerability caused by natural hazards and eventually to catastrophic failure. Hence, rapid structural damage detection is essential and important to save human life due to failure of structures or buildings. Most of the time, human loss occurs due to damage to the buildings. This paper aims to address these issues.

In the present study, numerous experiments have been carried out on two reinforced concrete building test specimens and on seven existing reinforced cement concrete structures.

The results presented here in this study show that the vibration measurements can be used to monitor the health of framed reinforced cement concrete buildings.

The present study is part of doctoral thesis of Varinder S. Kanwar, an original research work.

The purpose of this paper is to determine the level of compliance with National Collegiate Athletic Association (NCAA) and International Association of Athletics Federations (IAAF) Track and Field Hammer Facility Recommendations at Division I universities in the USA, and to determine factors related to perceptions of facility safety.

A 35‐item survey instrument was distributed to 279 applicable schools with a 28 percent response rate. Multiple regression analysis was utilized to determine factors significantly related to overall perception of safety.

A total of 78.1 percent participants in the study report compliance with the NCAA minimum recommendations and 38 percent also meet the IAAF standards. Analysis of the perceived safety reported by coaches reveal a significant prediction equation. Further analyses reveal significant risk involving some current facilities guidelines.

The NCAA may need to examine their present hammer facility guidelines and consider alignment with the new standards of the IAAF.

The paper creates a new application of statistical analyses for risk perception in a specific sport setting.

The present study assesses the impact resistance of the shear thickening fluids-filled (STFs-filled) foam through drop-hammer impact tests.

The maximum residual impact load and specific impact energy absorption rate of STF-filled foam are studied with varying thickness (4–14 mm), densities (0.35–0.6 g/cm3) and hardness (40–50 Rockwell Hardness C Scale (HRC)) under different ambient temperatures (−20−20 °C) and impact energies (25–75 J).

The following conclusions are obtained from this study: (1) the higher the impact energy, the greater the maximum residual impact force and energy absorption efficiency of the material; (2) the impact resistance of STF-filled foam can be improved with the decrease of ambient temperature, achieving the highest energy absorption rate at −10?. (3) STF-filled foam substrate has the highest impact resistance, the lowest maximum residual impact force and the highest energy absorption coefficient when the density is 0.35  g/cm3, the hardness is 45HC and the thickness is 10 mm.

This is the first paper to analyze the impact of both environmental factors and material properties on the impact resistance of STF-filled foam. The results show that the decrease in temperature and the increase in hardness can enhance the impact resistance of STF-filled foam.

The purpose of this paper is to articulate an ontological anarchist approach for an engaged post-human politics and present insurrection training as a pragmatic tool for researchers to directly transform the world.

The paper analyses how post-humanism has been criticised for dissolving political agency. It shows that this is due to the way post-humanism has been framed as sensitising and including non-humans into liberal politics. Instead, the paper examines anarchist-influenced post-humanism and combines this with the notion of multiple ontologies and ontological interventions. The paper presents the notion of insurrection training as offering the possibility for researchers to become emotionally sensitised to ontological difference. A case study of the “Seeds of Hope East Timor Ploughshares action” (1996) is used to illustrate what insurrection training and ontological interventions look like in practice. Finally, the paper makes suggestions as to how post-human researchers can apply this approach in their everyday lives.

The paper suggests that beyond a liberal framing of post-humanism as inclusion, there is also an ontological anarchist post-humanism that can support transformative impacts in the world. This form of post-humanism offers specificity of intervention and reflexive training practices. Insurrection training can offer new possibilities for post-humanist researchers: experience ontological difference, de-trivialise the everyday, connect to social movements, make post-human politics “doable” and offer “direct” change.

The paper addresses discussions that claim post-humanism is disabling political change. Its contribution is to map an anarchist post-humanism and extend this with concepts of multiple ontologies. It proposes the notion of insurrection training which places attention on the role of the researcher as an active agent that needs to be sensitised to ontological difference to carry out interventions. A case study of direct action illustrates what ontological intervention and insurrection training look like in practice. The case study suggests that insurrection training is an everyday performative practice that integrates and negotiates the personal, material and political. Finally, the paper suggests how researchers can adopt such an approach in their everyday lives.

Wind power is the one of best natural resources to meet the demands of electricity in India. In this regard, one of engineering college in Visakhapatnam has procured wind turbine generators of 200 kWp and got these installed on the rooftop of the college buildings for research and power generation. After starting the mills, huge vibrations were experienced by the staff and students in the laboratories and classrooms. So, the purpose of this paper is to carry out vibration and noise studies on wind turbine generator to identify the problem for high vibrations and suggest a novel method for vibration reduction.

Experimental vibration and natural frequency investigations are carried when wind velocity around 6.0 m/s using frequency analyzer, impact hammer, condenser microphone and accelerometer. An attempt is made to reduce the vibration and noise level of wind turbine generator by inserting a steel coil spring of 300 mm length having 20 turns in series with turnbuckle D shackle assembly, which is used to connect the wind turbine generator to the hook mounted on slab.

A high vibration velocity of 9.9 mm/s was observed on at base frame of wind turbine generator. The natural frequencies of hook and slab are observed in between 15 to 20 Hz from the natural frequency test. A high noise of 94.67 dBA is observed at a distance of 1 m from the base of wind turbine generator along the rotational axis of rotor. After modification to the baseline, WTG the vibration and noise levels are reduced to 4.8 mm/sec and 77.76 dBA, respectively.

This is the first time to study the huge vibrations generated in wind turbine generators installed on the rooftop of the college. Developed a novel methodology to reduce the vibrations by inserting a steel coil springs in turnbuckle D shackle assembly of wind turbine generators. After modification, wind turbine generator are running successfully without any high vibrations.

The purpose of this paper is to present a dual-robot pneumatic riveting system for fuselage panel assembly, including the system design, dynamic analysis and sensitivity analysis. The dual-robot pneumatic riveting system is designed to improve riveting efficiency and quality, thus finally replace the traditional two-man riveting mode where possible.

The dual-robot pneumatic riveting system has been designed by considering vibration reduction for the tools and isolation for robots. Nonlinear multi-body dynamic model including clearance and collision is established for investigating the dynamic performance and analyzing the systemic sensitivities with respect to the key variations. Semi-implicit Runge–Kuta algorithm is used for solving the dynamic equations and shop experiments are implemented to verify the effectiveness of the numerical simulations.

The simulation results show the tools can be held stably enough for riveting operation and the system sensitivity with respect to robot gesture can achieve the expected level. The experiment validates the proposed system with a good performance, and the riveting quality could adequately meet the requirements. The system is capable of installing an aluminum alloy countersunk 5 mm diameter rivet in 5 s.

The dual robot pneumatic riveting system is successfully developed and test. It has been applied in a project of fuselage panel assembly in the aircraft manufacturing industry in China.

To replace the traditional manual rivet installation, this paper presents a dual robot pneumatic riveting system and includes both the system design and dynamic analysis.