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In this experimental investigation, the behavior of strengthened/repaired heat-damaged one-way self-compacted concrete (SCC) slabs with opening utilizing near-surface-mounted-carbon fiber reinforced polymers (NSM-CFRP) strips was explored.

CFRP strip configurations, number of strips and inclination were all investigated in this study. For three hours, slabs were exposed to temperatures of 23°C and 500°C. Four-point load was applied to control slabs, enhanced slabs and repaired slabs.

The results indicate that exposing the slabs to high temperatures reduces their load capability. The number of strips and angle of inclination around the slab opening have a considerable impact on the performance of the strengthened and/or repaired slabs, according to the experimental results. The load capacity, toughness and ductility index of a strengthened and/or repaired slab with opening increase as the number of CFRP strips increases by 143.8–150.5%, 137.3–149.9% and 122.3–124.5%, respectively. The use of NSM strips around the opening with zero inclination showed higher load compared to the NSM strips around the opening with other angles.

It is frequently important to construct openings in the slabs for ventilation, electrical supply, and other purposes. Making openings in slabs might affect the structure’s performance since the concrete and reinforcing would be cut off. SCC is a new type of concrete mixture that can fill in all the voids in the formwork with its own weight without the help of external vibration.  As a result, it is necessary to reinforce the slab under flexure and increase the flexural strength of the SCC slab. Therefore, this work investigates the effect of using NSM-CFRP strip  on the behavior of one way SCC slabs that have been heat-damaged.

The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.

The purpose of this study is to investigate the effects of high-temperature oxidation tests and gas thermal shock tests on IC10 simulated components with thermal barrier coatings under different temperatures and oxidation times.

In the high-temperature oxidation test, specimens were oxidized at three different temperatures of 850, 980, and 1,100 °C for durations of 10, 20, 50, 100, 200, and 300 h, respectively. In the gas thermal shock test, specimens were pre-oxidized for 10, 20, 50, and 100 h, followed by a high-temperature gas thermal shock test at 1,100 °C.

In the high-temperature oxidation tests, with increasing oxidation time, the oxidation layer thickened, and the air-film holes diameter decreased. The microstructure of the bond coat transitioned from strip-like to block-like, and internal cracks transformed from numerous and short to larger and deeper. Below the bond coat, a noticeable disappearance layer of strengthening phase appeared, with increasing thickness. The strengthening phase in the substrate transitioned from regular square shapes to circles as temperature increased. In gas thermal shock tests at 1,100 °C, the oxidation weight gain ratio increased with longer pre-oxidation times, whereas the erosion weight loss ratio gradually decreased.

The originality and significance of this study lie in its departure from the typical subjects of high-temperature oxidation and thermal shock tests. Unlike common research targets, this study focuses on IC10 simulative specimens with thermal barrier coatings and air-film holes. Furthermore, it investigates the effects of varying temperatures and oxidation durations.

Authorities have set up numerous security checkpoints during times of armed conflict to control the flow of commercial and humanitarian trucks into and out of areas of conflict. These security checkpoints have become highly utilized because of the complex security procedures and increased truck traffic, which significantly slow the delivery of relief aid. This paper aims to improve the process at security checkpoints by redesigning the current process to reduce processing time and relieve congestion at checkpoint entrance gates.

A decision-support tool (clearing function distribution model [CFDM]) is used to minimize the effects of security checkpoint congestion on the entire humanitarian supply network using a hybrid simulation-optimization approach. By using a business process simulation, the current and reengineered processes are both simulated, and the simulation output was used to estimate the clearing function (capacity as a function of the workload). For both the AS-IS and TO-BE models, key performance indicators such as distribution costs, backordering and process cycle time were used to compare the results of the CFDM tool. For this, the Kerem Abu Salem security checkpoint south of Gaza was used as a case study.

The comparison results demonstrate that the CFDM tool performs better when the output of the TO-BE clearing function is used.

The efforts will contribute to improving the planning of any humanitarian network experiencing congestion at security checkpoints by minimizing the impact of congestion on the delivery lead time of relief aid to the final destination.

The paper aims to elaborate on the potential for regeneration of Bagamoyo (Tanzania) through adaptive reuse of its heritage sites. The town was the most important harbour for ivory and slaves of the East-African mainland during the 19th and early 20th century and the colonial capital of German East-Africa between 1885 and 1890. Today, it has 85,000 inhabitants who mainly live in informal settlements while stone town closer to the coast is largely abandoned with its historical buildings in a poor state of conservation.

The first part of the paper describes the history and heritage of the old stone town Bagamoyo, and how it impacts its identity. Additionally, it summarises the critical reception of the town's role in the application to UNESCO World Heritage for “The Central Slave and Ivory Trade Route”. This, in order to consider the reuse of its heritage sites more as part of a layered regeneration process than of a singular narrative for preservation. The second part presents research-by-design proposals investigating the economic, social and cultural potentialities of three spatial layers: the main street, the coastal strip and the shoreline.

The identity and therefore also urban regeneration of post-colonial towns such as Bagamoyo is the result of a complex combination of different narratives rather than of a singular one.

Bagamoyo's heritage has been studied as a driver for international tourism linked to slavery but without successful implementation. This study proposes an alternative perspective by investigating its potential for urban regeneration in line with local needs. Developed in the context of a master studio of architectural design, it presents an innovative didactic approach. Moreover, the methodology of research-by-design can be inspirational for other historical towns.

This study aims to explain the market-oriented transformation dilemma of Chinese urban investment and development companies (UIDCs; also known as local government investment and financing companies) and objectively evaluate their transformation efficiency from both static and dynamic perspectives. The results of the research provide methodological bases for improving the transformation efficiency of UIDCs, thus pointing out the direction for the rational planning of their transformation path.

This study takes Chinese UIDCs in market transformation during 2015–2019 as the research object and uses principal component analysis to screen the index system for measuring the efficiency of market transformation. It then uses a three-stage data envelopment analysis model and the Malmquist productivity index to evaluate the market transformation efficiency of these companies during 2015–2019 and comprehensively analyzes the influence of external environmental factors on the market transformation of Chinese UIDCs.

Research results show that the transformation efficiency of Chinese UIDCs is low and slow overall and that large spatial and temporal differences exist. The transformation efficiency of UIDCs located in eastern China is higher than that of UIDCs in central and western China. The higher the external environmental factors of regional GDP, local debt service pressure and credit rating, the more likely they are to cause input redundancy in the transformation process of Chinese UIDCs, which is not conducive to their market-oriented transformation. In addition, the higher the urbanization rate, the more effective it is to improve the efficiency of market-oriented transformation of UIDCs. If the influence of environmental factors is stripped away, both the overall efficiency value and pure technical efficiency value of market-oriented transformation of Chinese UIDCs will increase while the scale efficiency value becomes smaller.

This research measures the transformation efficiency of Chinese UIDCs and comprehensively analyzes the influence of external environmental factors on their market-oriented transformation. The goal is to enrich the study of the market-oriented transformation efficiency evaluation index system of Chinese UIDCs at the theoretical level and provide important reference values for improving the efficiency of market-oriented transformation of Chinese UIDCs at the practical level.

This paper aims to explore factors impacting citizen intention toward artificial intelligence (AI) adoption, considering government regulation as a moderating variable. It focuses on the Palestinian Cellular Communications Sector in Gaza Strip, providing insights into the citizen-AI relationship dynamics. The research contributes to enhancing comprehension of AI technology from clients’ perspective.

To test the hypotheses, a questionnaire was used in an empirical study to collect primary data. In total, 347 Palestinian citizens responded to the survey.

The findings of this paper reveal that perceived usefulness, perceived ease of use, perceived risks, social influence, user experience and privacy and security concerns significantly influence citizen intention toward AI adoption. Furthermore, government regulations as a moderating variable strengthen the impact of perceived usefulness, perceived ease of use, perceived risks, social influence, user experience and privacy and security concerns on citizen intention toward AI acceptance and adoption. Thus, further research should explore specific domains and cultural contexts to gain a more comprehensive understanding of the factors shaping acceptance and adoption.

The findings of the study should be understood in the context of their limitations. First, the study ignored cultural or domain-specific subtleties in favor of generic characteristics, which calls for more research in these particular circumstances. Second, relying on self-reported data might result in biases and limitations due to subjectivity in reporting, indicating the necessity for alternate data gathering methods and approaches in future research.

Policymakers, developers and organizations working to promote the acceptability and implementation of AI applications should consider the practical implications of this study’s results. To secure the long-term use of AI technologies in a responsible and user-centric way, policymakers should give priority to public education and awareness, user-centered design and ethical AI development techniques. They should also stimulate partnerships and create monitoring systems.

This paper investigates the originality of factors that influence citizen intention toward AI acceptance and adoption. It uniquely examines the moderating role of government regulations in shaping this intention. By addressing this novel aspect, the paper contributes to advancing our understanding of the complex dynamics surrounding citizen intentions toward AI applications.

The paper aims to fabricate shape memory composites using polylactic acid (PLA) matrix and graphite. Shape memory polymers are a promising family of materials for biomedical applications because of their favourable mechanical properties, fast reactions and good biocompatibility. For most SMPs, however, achieving controllable sequential shape change is challenging.

In the present work, 4D printing technology is used to fabricate shape memory composites using polylactic acid (PLA) matrix and graphite. A comparative study of pure PLA and graphite’s different weight % composition has been done.

By carefully managing the deformation state, PLA with graphite shape memory composites produced controllable sequential deformation with an amazing shape memory effect. Surface morphology, thermal properties, melt flow index and shape recovery tests have all been carried out to assess the qualities of manufactured samples.

This is a one-of-a-kind to fabricate shape memory composites using graphite and a PLA matrix. Thus, this research attempts to deliver the possible use of PLA/graphite composites fabricated using 4D printing in robotics and biomedical devices.

The purpose of the study is to investigate female prisoners’ perspectives on why they gain weight while in prison.

A qualitative design was used with semi-structured interviews with six females currently residing in a prison in the south of England.

Analysis of the data generated three themes relating to the reasons why women gain weight in prison. These were labelled as “The only thing you haven’t got to ask permission for is your food, it’s just handed to you”, “If you’ve been stripped of the things that make you happy, or that you are addicted to, eating can soothe you” and “prison can make you take better care of your health”.

The results identify perceived reasons why women gain weight in prison uniquely from the female prisoner perspective. The implications of the research identify the need for systemic change throughout different prison departments to enable women to maintain a healthy weight during their custodial sentence.

The purpose of the study is to design the compensation network of a dynamic wireless power transfer system, considering the movement of the receiving coil along an electrified track with a large number of inductors buried on the road.

A finite element model has been developed to calculate the self-inductances of transmitting and receiving coils as well as the mutual inductances between the receiving coil and the transmitting ones in the nearby and for various relative positions. The calculated lumped parameters, self-inductances and mutual inductances depending on the relative positions between the coils, have been considered to design the compensation network of the active coils, which is composed of three capacitive or inductive reactances connected in the T form. The optimal values of the six reactances, three for the transmitting coils and three for the receiving one, have been calculated by resorting to the Genetic Algorithm NSGA-II.

In this paper, the results obtained by means of the optimizations have broadly discussed. The optimal values of the reactances of the compensation networks show a clear trend in the receiving part of the circuit. On the other hand, the problem seems very sensitive to the values of the reactances in the transmitting circuit.

Dynamic wireless power transfer system is one of the newest ways of recharging electric vehicles. Hence, the design of compensation networks for this kind of systems is a new topic, and there is the need to investigate possible solutions to obtain a good performance of the recharging system.