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The interaction between rock mass structural planes and dynamic stress levels is important to determine the stability of rock mass structures in underground geotechnical engineering. In this work, the authors aim to focus on the degradation effects of fracture geometric parameters and unloading stress paths on rock mechanical properties.

A three-dimensional Particle Flow Code (PFC3D) was used for a systematic numerical simulation of the strength failure and cracking behavior of granite specimens containing prefabricated cracks under conventional triaxial compression and triaxial unilateral unloading. The authors demonstrated the unique mechanical response of prefabricated fractured rock under two conditions. The crack initiation, propagation, and coalescence process of pre-fissured specimens were analyzed in detail.

The authors show that the prefabricated cracks and unilateral unloading conditions not only deteriorate the mechanical strength but also have significant differences in failure modes. The degrading effect of cracks on model strength increases linearly with the decrease of the dip angle. Under the condition of true triaxial unilateral unloading, the deterioration effect of peak strength of rock is very significant, and unloading plays a role in promoting the instability failure of rock after peak, making the rock earlier instability failure. Associating with the particle vector diagram and crack coalescence process, the authors find that model failure mode under unilateral loading conditions is obviously distinct from that in triaxial loading. The peak strain in the unloading direction increases sharply, resulting in a new shear slip.

This study is expected to improve the understanding of the strength failure and cracking behavior of fractured rock under unilateral unloading.

The purpose of this paper is to introduce a variable distance pneumatic gripper with embedded flexible sensors, which can effectively grasp fragile and flexible objects.

Based on the motion principle of the three-jaw chuck and the pneumatic “fast pneumatic network” (FPN), a variable distance pneumatic holder embedded with a flexible sensor is designed. A structural design plan and preparation process of a soft driver is proposed, using carbon nanotubes as filler in a polyurethane (PU) sponge. A flexible bending sensor based on carbon nanotube materials was produced. A static model of the soft driver cavity was established, and a bending simulation was performed. Based on the designed variable distance soft pneumatic gripper, a real-time monitoring and control system was developed. Combined with the developed pneumatic control system, gripping experiments on objects of different shapes and easily deformable and fragile objects were conducted.

In this paper, a variable-distance pneumatic gripper embedded with a flexible sensor was designed, and a control system for real-time monitoring and multi-terminal input was developed. Combined with the developed pneumatic control system, a measure was carried out to measure the relationship between the bending angle, output force and air pressure of the soft driver. Flexible bending sensor performance test. The gripper diameter and gripping weight were tested, and the maximum gripping diameter was determined to be 182 mm, the maximum gripping weight was approximately 900 g and the average measurement error of the bending sensor was 5.91%. Objects of different shapes and easily deformable and fragile objects were tested.

Based on the motion principle of the three-jaw chuck and the pneumatic FPN, a variable distance pneumatic gripper with embedded flexible sensors is proposed by using the method of layered and step-by-step preparation. The authors studied the gripper structure design, simulation analysis, prototype preparation, control system construction and experimental testing. The results show that the designed flexible pneumatic gripper with variable distance can grasp common objects.

Breast cancer is the most diagnosed type of cancer in the world, and mastectomies to remove tumors are still common. An external breast prosthesis (EBP) can be used to minimize the asymmetry, due to the ablation. Some governments do not cover costs of that assistive technology, and women end up using socks and fabric pockets filled with seeds, to simulate the volume lost in the surgery. This study aims to offer to those women a decent solution, ergonomic, but still affordable.

The authors interviewed 20 mastectomized Brazilian women, listened to their relate and 3D scanned them, to give rise to personalized external lightweight breast prostheses. The authors used free software for computer-aided design and computer-aided manufacturing, and low-cost 3D printers. From the strategy of bespoke products, this study generalized the method, to conceive mass customized prostheses, in a compromise solution that reduces personalization, conserving the best features of design.

This study achieved a method to manufacture ergonomic, bespoke external breast prostheses, using low-cost technology. Previous literature made them using expensive scanners, software and printers.

The authors validated this method during pandemic, which restricted the number of patients the authors could have access to. This impacted authors’ possibility to work on matching the color of the final product and real skin. The authors understood, though, that precision of color, in the final product, is challenging, because of the peculiar aspects of human skin.

Using the method the authors proposed, personalized external breast prostheses can be manufactured using low-cost resources, democratizing better quality of life for more breast cancer survivors.

This paper aims to examine how collaborative supplier development (SD) activities, supplier capabilities and buyer–supplier relationship interrelate in technology-based, luxury product business contexts characterized by small volumes, difficult targets and resource constraints relative to those targets.

Using inductive case research method, the authors investigate multiple embedded cases involving six dyadic buyer–supplier relationships of two luxury product manufacturers in the motorcycle and automotive industries. Each dyad represents an important sub-system for which the buying firm committed significant SD efforts to help the supplier successfully achieve difficult targets.

The analysis reveals how paradoxical tensions might emerge as the firms engage in successful SD activities, which could lead to decreasing relationship commitment ultimately resulting in the termination of the relationship. The authors utilize the “value co-creation and value capture” paradox framework to understand the SD and relationship dynamic and characterize it as developing-leveraging paradox to explain its dualities, i.e. commitment-based SD efforts (increasing value co-creation), and unilateral leveraging of the newly acquired capabilities (increasing value capture) by both the buyer and the supplier. Overemphasis on value capture by one of the exchange partners spurs a detrimental vicious cycle leading to the decline of the relationship.

The study explains the paradoxical dynamics that may emerge in SD activities of innovative, technologically complex, luxury product firms. The findings contribute to the SD literature by highlighting how learnings from SD activities could contribute to the dark sides of buyer–supplier relationship. The technologically complex, luxury product contextual characteristics of the study may limit the generalizability of the study findings.

The study provides novel insights into the emergence and management of paradoxes in buyer–supplier relationships, in terms of virtuous and vicious dynamics of developing-leveraging.

The objective of this chapter is to discuss how different techniques in Regional Science and Peace Science and the emerging techniques in Management Science can be used in analysing Disaster Management and Global pandemic with special reference to developing countries. It is necessary for me to first discuss the subjects of Disaster Management, Regional Science, Peace Science and Management Science. The objective of this chapter is to emphasise that the studies of Disaster Management should be more integrated with socioeconomic and geographical factors. The greatest disaster facing the world is the possibility of war, particularly nuclear war, and the preparation of the means of destruction through military spending.

The purpose of this paper is to demonstrate the impact of the welding sequence on the substrate plate distortion during the wire and arc additive manufacturing (WAAM) process. This paper also aims to show the capability of finite element simulations in the prediction of those thermally induced distortions.

An experiment was conducted in which solid aluminum blocks were manufactured using two different welding sequences. The distortion of the substrates was measured at predefined positions and converted into bending and torsion values. Subsequently, a weakly coupled thermo-mechanical finite element model was created using the Abaqus simulation software. The model was calibrated and validated with data gathered from the experiments.

The results of this paper showed that the welding sequence of a part significantly affects the formation of thermally induced distortions of the final part. The calibrated simulation model was able to capture the different distortion behavior attributed to the welding sequences.

Within this work, a simulation model was developed capable of predicting the distortion of WAAM parts in advance. The findings of this paper can be used to improve the design of WAAM welding sequences while avoiding high experimental efforts.

With the development of artificial intelligence, proximity sensors show their great potential in intelligent perception. This paper aims to propose a new planar capacitive sensor for the proximity sensing of a conductor.

Different from traditional structures, the proposed sensor is characterized by sawtooth-structured electrodes. A series of numerical simulations have been carried out to study the impact of different geometrical parameters such as the width of the main trunk, the width of the sawtooth and the number of sawtooths. In addition, the impact of the lateral offset of the approaching graphite block is investigated.

It is found that sensitivity is improved with the increase of the main trunk with, sawtooth width and sawtooth number while a larger lateral offset leads to a decrease in sensitivity. The performance of the proposed planar capacitive proximity sensor is also compared with two conventional planar capacitive sensors. The results show that the proposed planar capacitive sensor is obviously more sensitive than the two conventional planar capacitive sensors.

In this paper, a new planar capacitive sensor is proposed for the proximity sensing of a conductor. The results show that the capacitive sensor with the novel structure is obviously more sensitive than the traditional structures in the detection of the proximity conductor.

With the popularity of high-rise buildings, wall inspection and cleaning are becoming more difficult and associated with danger. The best solution is to replace manual work with wall-climbing robots. Therefore, this paper proposes a design method for a rolling-adsorption wall-climbing robot (RWCR) based on vacuum negative pressure adsorption of the crawler. It can improve the operation efficiency while solving the safety problems.

The pulleys and tracks are used to form a dynamic sealing chamber to improve the dynamic adsorption effect and motion flexibility of the RWCR. The mapping relationship between the critical minimum adsorption force required for RWCR downward slip, longitudinal tipping and lateral overturning conditions for tipping and the wall inclination angle is calculated using the ultimate force method. The pressure and gas flow rate distribution of the negative pressure chamber under different slit heights of the negative pressure mechanism is analysed by the fluid dynamics software to derive the minimum negative pressure value that the fan needs to provide.

Simulation and test results show that the load capacity of the RWCR can reach up to 6.2 kg on the smooth glass wall, and the maximum load in the case of lateral movement is 4.2 kg, which verifies the rationality and effectiveness of the design.

This paper presents a new design method of a RWCR for different rough wall surfaces and analyses the ultimate force state and hydrodynamic characteristics.

This paper aims to investigate the differential effects of vertical attributes and horizontal attributes on visit intention under proximal and distal sensory imagery in travel live streams.

This research used a multimethod approach with four studies. Three designed experiments were first employed to prove casual relations of the hypothesized relations. Then, a structural model provided a new sample of the framework.

The results suggest that visit intention is higher when vertical (vs horizontal) attributes are associated with proximal (vs distal) sensory imagery. Physical presence mediates the interaction effects between attribute type and sensory imagery on visit intention.

The finding offers suggestions for multilateral information providers' capability of real-time advertising, seller-focused technology development and proactive relationship management with potential consumers.

Previous study is less sufficient to describe consumers' traveling interactivities in live-streaming media, where streamers are capable of modifying attribute-based messages and sensory modalities. Rather than focusing on imagery as a comprehensive modality or visual-dominated imagery, this study examines the interaction effects between attribute type and sensory imagery on visit intention. Drawing on reason-based choice and distance-on-distance theories, the finding enriches the evaluation of the effectiveness of live-streaming marketing across varying sensory interactions.

When bending a large diameter thin-walled tube, the thickn ess of outer side wall will reduce greatly, which leads to a decrease of structural strength of the tube. To solve this problem, this paper investigated the deformation principles of an eccentric tube in the rotary draw bending process, trying to find a way to reduce the wall thickness difference between inner and outer diameters.

An finite element model is established for analyzing the deformation of an eccentric tube in rotary draw bending process. The wall thickness distribution of the formed pipe was analyzed along the axis and diameter, respectively.

It is found that there exists an optimal eccentricity between the inner and outer circle center of the tube cross-section. If the eccentricity of the tube is chosen properly, it is possible to get a bent tube with equal thickness of inner and outer side walls. In addition, it is also found the optimal eccentricity on the cross-section can be influenced by bending radius, wall thickness, diameter and bending angle. The optimal eccentricity increases greatly with the decreasing of bending radius, the increase of outer diameter and the increase of wall thickness. The influence of bending angle on the optimal eccentricity can be divided into two situations. When the bending angle is small, the optimal eccentricity increases with the increase of bending angle. When the bending angle exceeds a certain value, the pipe enters a stable forming state. The optimal eccentricity of the stable forming region does not change with the bending angle.

Such a research is beneficial for reducing the thickness difference between inner and outer side walls in the rotary draw bending process.