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Comprehensive Review of Control Techniques for Various Mechanisms of Parallel Robots
Get PDFThis study provides a literature review of control schemes associated with parallel robots. Various types of parallel robots have been discussed, including the Delta Robot, 2 DOF Parallel Robot, 3 DOF Parallel Robot, 4 DOF Parallel Robot, the R4 Redundantly Parallel Robot, the 5R Parallel Robot, 6 DOF Parallel Robot (Hexa Robot), Cable-Driven Parallel Robot, and Parallel Quadruped Robot. Additionally, an overview of the control structuring within these systems has been provided. This study covers the developments occurring between 2008 and 2024. These controllers are PI Control, PID Control, Genetic Algorithm Optimized PID Control, Extended PD Control, Augmented Nonlinear PD Control, Model-Based PD Control, Synchronous PD Control Based on a Time-Delay Estimator, Identification-Based Control, Image-Based Control, Lagrangian Formulation-Based Control, Observers-Based Control, Optimal PID Control, Anti-Windup Based PID Control, Model-Based Control, PLC-Based Control Architecture, Feedback PID Control, and Computed Torque Control, Hedge Algebras Control, B-Spline Neural Network Control, Fuzzy Logic Control, Model-Based control, Cooperative Control, Brain Emotional Learning-Based Intelligent Control, Nonlinear Model Predictive Control, Fuzzy Logic-Based Sliding Surface Control, Fuzzy PID Control, Fuzzy- Based PID Control, Interval Type-2 Fuzzy Logic Control Fuzzy Logic based Neural Network Control, Nonlinear Model Predictive Control, Synchronous Sliding Mode Control, Observer-Based Sliding Mode Control, Sliding Mode-Based on Backstepping Control, LQ Optimal Control, Adaptive Fuzzy Control, Rise Feedback Control, Dual-Space Feedforward Control, Dual-Space Feedforward Control in the Cartesian Space, Dual-Space Feedforward Control, Dual Mode Adaptive Control, Nonlinear Dual Mode Adaptive Control, Optimized Fuzzy Adaptive PID Control, Adaptive Position-Force Control, Adaptive Admittance Control, and Robust Nonlinear Adaptive Control, Adaptive Robust Control, Adaptive Control, and Adaptive Terminal Sliding Mode Control, Robust control, fault tolerant controllers, and passivity control. The primary contribution is a literature review of control-based strategies for parallel robots, designed to inform those interested in control-oriented parallel robot research
Valorising excavated low-grade waste clay in limestone calcined clay cement system for 3D printing applications
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Data will be made available on request.Limestone calcined clay cement (LC3) presents a suitable low-carbon cementitious material for large-scale 3D printing due to its long open time. This study investigates the impact of substituting up to 100 % natural aggregate with recycled brick aggregates (BA) on the engineering properties, durability and printing properties of LC3. BA's rough surface and irregular shape reduced the workability of the LC3 mixtures even though the water absorption of BA was compensated for by adding extra water. The mechanical strength increased significantly in the presence of BA of around 36 %–62 %. Moreover, incorporating BA was found to boost the hydration and allowed it continue due to the presence of additional water in its microstructure. The water absorptions of LC3 prepared with up to 70 % replacement level of aggregates with BA were comparable to the reference mix, while a 100 % replacement level increased the water absorption by around 9 %. In contrast, incorporating BA improved the freeze-thaw resistivity by up to 25 %. Moreover, it was found that incorporating BA improved the layer quality of 3D-printed filaments. The results of this study present a breakthrough in the recycling of brick aggregates in LC3 systems for both cast and 3D printing applications, which will help develop a more environmentally friendly mixture with high engineering performance
The political economy of group domination and pre-electoral violence
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Not applicableJEL Classification: D72, D74, F50.Supplementary Information is available online at: https://link.springer.com/article/10.1007/s00148-025-01125-z#Sec15 .We construct a theoretical model to study the effects of pre-electoral violence in a political economy set-up. In an environment pervaded by ethnic cleavages, we model violence in terms of a group destroying the rival group’s production potential, which impairs that group’s productivity not only in material terms but also by breaking the targeted group’s cohesion and morale through fear and intimidation. We show that the destruction perpetrated by either group is increasing in their rival’s productivity, and is decreasing in the potential uncertainty surrounding the political process, in their own group’s share of the population, and in the degree of authoritarianism of the studied society. Our case studies on Zimbabwe, Kenya, and Nigeria provide support to our theory
Environmental and economic sustainability assessment of food waste management options in a tortilla industry (a case study)
Get PDFThe aim of this study is to analyse the waste generated in tortilla production process in a tortilla industry located in London and consider a number of potential solutions. This study evaluated the environmental and economic impacts related to anaerobic digestion, using the food waste as animal feed, and reworking the food waste. The impacts of each waste management options were compared to determine the most sustainable option. The Life Cycle Assessment (LCA) and Life Cycle Costs (LCC) methods have been applied using SimaPro 9.3.0.3. The functional unit of the study was set to 1 kg of tortilla. The system boundary included the tortilla production processes (mixing, forming, baking, cooling and packaging) and food waste management scenarios. The LCA results showed that reworking the waste will substantially reduce environmental impacts across all assessed categories. The LCC results show that reworking the food waste within the tortilla production process is the best option with the lowest net costs of GBP4.96/kg. This is followed by AD with a net cost of GBP 5.08/kg and lastly by animal feed with a net cost of GBP 6.45/kg.This project was funded by the BBSRC-CDT (Project ref number: BB/V011391/1) and ESPRC through the Park Royal Net Zero Food Systems
Early Childhood Exposure to Endocrine Disrupting and Neurotoxic Chemicals: Associations with Internalizing and Externalizing Difficulties from Childhood to Adolescence in the Rhea Cohort, Crete, Greece
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Data supporting these findings are available upon request from the corresponding author K.K.Many common chemicals are known or suspected to harm brain development, and children are particularly vulnerable, yet research on their long-term effects on mental health is limited. This study investigated the associations of early childhood exposure to endocrine disrupting and neurotoxic chemicals with the development of internalizing, externalizing, and attention-deficit/hyperactivity disorder (ADHD) symptoms from early childhood through adolescence in 387 children from the Rhea cohort in Crete, Greece. At age 4, serum concentrations of 3 organochlorine pesticides and 14 polychlorinated biphenyls, and urinary concentrations of 7 phthalate metabolites and 6 dialkyl phosphate metabolites were measured. Children’s symptoms were assessed via maternal reports at ages 4, 6, 11 and 15 years. Using generalized estimating equation models, the study found that early exposure to hexachlorobenzene (HCB) and dichlorodiphenyldichloroethylene (DDE) was associated with increased externalizing symptoms across ages in girls [beta (95% CI): 0.20 (0.04, 0.37) and 0.11 (0.01, 0.21), respectively]. Among girls, low molecular weight (LMW) phthalates were also linked to elevated internalizing and externalizing symptoms, as well as ADHD-related difficulties [beta (95% CI): 0.15 (0.04, 0.26), 0.13 (0.01, 0.25), and 0.13 (0.02, 0.24), respectively]. Additionally, exposure to organophosphate pesticides was associated with increased externalizing and ADHD symptoms [beta (95% CI): 0.13 (0.04, 0.22) and 0.12 (0.04, 0.20), respectively]. The findings suggest that early childhood exposure to environmental chemicals may have long-term effects on emotional and behavioral development, with pronounced effects observed only in girls.The Rhea project was financially supported by European projects (EU FP6-2003-Food-3-NewGeneris, EU FP6. STREP Hiwate, EU FP7 ENV.2007.1.2.2.2. Project No 211250 Escape, EU FP7-2008-ENV-1.2.1.4 Envirogenomarkers, EU FP7-HEALTH-2009-single stage CHICOS, EU FP7 ENV.2008.1.2.1.6. Proposal No 226285 ENRIECO, EUFP7-HEALTH-2012 Proposal No 308333 HELIX, FP7 European Union project, No. 264357 MeDALL), the Greek Ministry of Health (Program of Prevention of obesity and neurodevelopmental disorders in preschool children, in Heraklion district, Crete, Greece: 2011–2014; Rhea Plus: Primary Prevention Program of Environmental Risk Factors for Reproductive Health, and Child Health: 2012-15), the Hellenic Ministry of Health and the General Secretariat for Research and Innovation. The research project entitled “Developmental Trajectories of Internalizing and Externalizing Symptoms from Early Childhood to Adolescence: The Role of Psychosocial and Environmental Factors—IntExt Trajectories” was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “2nd Call for H.F.R.I. Research Projects to support Faculty Members & Researchers” (Project Number: 4397)
The KGB's Perception of DIA at the End of the Cold War
No full textThe KGB trained its officers to view the US Defense Intelligence Agency as a formidable enemy. This article explores an article published in the KGB's internal journal, Сборник КГБ (KGB Digest) in 1989. It describes the KGB's perceptions of DIA and recommends efforts that the KGB should take against it.https://www.afio.com/available-excerpts-from-the-intelligencer.htm
Lean manufacturing principles as a driver for digital transformation: Adoption insights and performance outcomes in Turkish SMEs
Get PDFThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonManufacturing companies have started to embrace Digital Transformation (DT) technologies to stay competitive and enhance their operational performance. However, the real industry implementation of DT technologies has proven challenging, particularly for small and medium-sized enterprises (SMEs) that face unique obstacles, especially within developing countries like Turkey. To improve the success rate, recent studies have been investigating the role of Lean Manufacturing (LM) principles to aid the adoption of DT technologies. Despite this interest, research on how LM principles can support DT adoption remains limited, particularly for SMEs. While larger corporations with greater resources are more frequently studied, SMEs often fall behind in DT adoption. Addressing this gap, this study examines how LM principles can aid Turkish manufacturing SMEs in adopting DT technologies, with the goal of improving their operational performance.
The theoretical lens of this research is institutional theory supported with contingency theory, to provide a more comprehensive understanding of DT technology adoption within SMEs in a developing country. While institutional theory offers valuable insights as one of the primary theoretical lenses of DT, existing research indicates that it often overlooks the specific challenges SMEs encounter in dynamic and diverse environments like manufacturing. To address this limitation, contingency theory is incorporated into the framework. As a result, the theoretical model is based on institutional theory, reinforced by contingency theory, to examine the impact of LM principles on the adoption of DT technologies in Turkish SMEs, with the goal of enhancing operational performance. Developing and validating this theoretical framework not only deepens the understanding of DT adoption in SMEs but also expands the institutional theory by establishing a robust model tailored to a more complex environment with specific needs and challenges of SMEs in developing countries.
To accomplish the research objectives, this study adopted a quantitative research approach. A questionnaire survey was administered, with responses collected from 208 participants representing Turkish SMEs. Following data collection, quantitative analysis was conducted using Structural Equation Modelling (SEM) with IBM SPSS and AMOS software. The SEM analysis results indicate that LM principles positively influence the adoption of DT technologies within Turkish SMEs, providing insights into the specific LM principles that drive this impact. Additionally, the analysis revealed that institutional pressures, specifically mimetic, coercive, and normative pressures arising from competitors, government regulations, and industry further supported DT adoption in Turkey. The findings also provide evidence that DT technologies contribute to improved operational performance within Turkish SMEs.
This research offers empirical evidence that LM principles support DT technology adoption in Turkish SMEs, providing valuable insights into how LM principles can contribute to DT adoption processes. From a theoretical perspective, the study extends the institutional theory framework by adapting it to more complex environments through the integration of contingency theory. Additionally, the findings provide practical guidance for managers on aligning their strategies to facilitate DT adoption and inform policymakers on the effects of creating supportive policies that enhance DT adoption among SMEs
Sustainability Reporting and External Assurance: Evidence From UK Listed Firms
Get PDFThis paper develops and tests a model explaining why some companies obtain external assurance for their sustainability reports while others do not. Our model integrates rational choice and stakeholder theories, providing novel insights into the sustainability assurance literature. Data were collected via an online questionnaire from 105 UK listed companies, and partial least squares structural equation modelling (PLS‐SEM) was employed to test the proposed model. We found that decision makers' perceived benefits of external assurance exert a direct positive effect, while perceived costs have a direct negative effect. Indirectly, external assurer independence and market competition positively influence the decision through perceived benefits, whereas adherence to sustainability reporting guidelines has an indirect negative effect. Additionally, institutional investors exert a direct positive impact on the decision to obtain assurance. Interestingly, when institutional investors demand external assurance, the influence of decision makers' perceptions of benefits and costs appears to diminish. These findings advance understanding of the interplay between rational choice and stakeholder theories in shaping decisions to obtain sustainability assurance. The study also carries practical implications for academics, business decision makers, external sustainability assurance providers and policymakers involved in the governance and oversight of sustainability reporting.The authors received no specific funding for this work
Recovered cellulosic fibres as a novel carrier for self-healing cementitious materials
No full textThis thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonCementitious materials are the most widely used construction material due to their ability to be used in a wide range of applications. However, cementitious materials place environmental stresses by OPC alone, accounting for 7% of global man-made CO2 emissions. Concrete is susceptible to microcracking, which puts a significant financial burden on the industry to repair. The use of self-healing technology has been an effective method in managing microcracking autonomously. This thesis aims to develop a sustainable selfhealing technology utilising recovered cellulose waste material from wastewater treatment as a novel carrier material for the application of self-healing cementitious materials. The approach used in this thesis involves a comprehensive experimental regime in which L. Pakistanensis was selected from a number of soil isolated microorganisms to be the most suitable for self-healing cementitious applications. The media was optimised for this particular bacterium to improve ureolytic activity to maximise CaCO3 production. The bacterial spores were then immobilised and coated to compare leakage, protective capabilities, and survival after immobilisation. Finally, the immobilised recovered cellulosic fibres were then used as additives in mortar to promote self-healing, in which the mechanical properties were measured, along with self-healing capabilities, monitoring the crack width and regained strength of the self-healing material. Finally, the healed products were then characterised using SEM, EDS, FTIR, and XRD to identify the material being produced. This study demonstrates the healing capabilities of a novel wild strain of bacterium, in which the optimised nutrients were able to show CaCO3 production of 0.43 g/100 mL after 72 hours. It was also able to demonstrate that upon investigating the microstructure of the immobilised bacteria and nutrients using oven drying, CaCO3 was produced, which was absent in the freeze-dried specimens. Furthermore, by utilising RCF as a carrier, it was able to heal a crack width of 0.60 mm within 28 days. Additionally, exposure to various healing conditions presented novel brown coloured healing products when exposed to 5% CO2. This study also uncovered the challenges associated with the requirement of liquid water for healing to occur, in which healing was observed with the use of RCF. Signs of healing were observed within 28 days in relative humidity conditions (60% and 95%). Finally, coating immobilised RCF with sodium silicate (30%) was able to demonstrate a regained strength of 47.26% within 28 days. This study shows the valorisation of a waste material which provides excellent self-healing capabilities due to its unique internal structure system, moisture absorption capabilities, and crack width controlling ability. It can therefore be selected as a suitable additive to cementitious material to promote effective healing. Although current challenges limit specific applications of self-healing technology. However, this novel carrier provides an alternative sustainable carrier option, which improves the application options of self-healing technology. There are limited studies in the literature using L. Pakistanensis and RCF for selfhealing applications, along with showing the ability of this novel self-healing agent to work without the presence of liquid water. These findings in this thesis contribute to a circular economy approach in the use of recovered material at the end of their service life and widen the application for self-healing, not limited to the presence of liquid water
Acceptability and feasibility of a sensor-instrumented ‘SmartSocks’ wearable prototype to detect agitation in people with dementia
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Code used in the data preparation and analysis is available at https://github.com/creesebyron/SmartSocks. Consent was not obtained for open posting of data. Data are embargoed on Brunel University of London’s research data repository, Figshare (10.17633/rd.brunel.30127036) and accessible via request. Access will be granted once users have consented to the data sharing agreement.Letter to Editor.The project is funded by Innovate UK (Biomedical Catalyst 2022 Round 2: Industry-led R&D), project number 10055596. This study was supported by the National Institute for Health and Care Research (NIHR) Exeter Biomedical Research Centre
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