Design Tool Research Articles

Effect of Recruitment Practices on Employees’ Performance in Public Universities in Nyanza Region, Kenya

Employee performance is integral to organizational success, yet public universities in Kenya have faced challenges in achieving satisfactory performance despite implementing human resource management (HRM) practices. This study aimed to investigate the effect of recruitment practices on employee performance in public universities in Nyanza region, Kenya. The target population comprised of 3,129 individuals, and the sample size of 355 teaching and non-teaching staff were determined using the Yamane formula, employing random sampling techniques for data collection. A structured questionnaire was utilized as the primary data collection tool in a quantitative research design. Cronbach's alpha was calculated for each scale in the questionnaire. Data analysis was conducted using both descriptive statistics and inferential statistics with the aid of SPSS version 23. To ensure reliability, the results were as follows: recruitment practices have a significant positive effect on employee performance ((β = 0.165, p<0.05). The study concluded that recruitment practices have a significant positive effect on employee performance. The study recommended that hiring decisions in universities should always be made on the basis of a person’s potential to do a job. The study recommended that hiring decisions in universities should be made on the basis of a person’s potential to do a job. The recruitment process should continue to be done in a transparent manner and the recruitment processes in the universities should keep on being improved to enhance employee satisfaction. The employee selection process should always be done in an ethical manner and in a manner that is fair.

Running Towards a Better Brand Attitude: How Gamification in Nike Run Club Can Help?

AbstractThe dynamics of the knowledge-based economy are intrinsically linked to the concept of gamification, which has been increasingly discussed in the context of companies’ marketing strategies. It is therefore necessary to understand how gamification can be strategically applied in different contexts to increase the performance and competitiveness of companies. This paper aimed to analyze how gamification impacts customers’ intention to participate in the gamification process and how this strategy influences customers’ attitudes towards the brand. Multiple linear regression analyses were conducted in a sample of 238 Portuguese consumers using the Nike Run Club application. The study revealed that gamification can be an effective tool to increase users’ interaction with brands. Perceived usefulness, perceived social influence, engagement intention and gamification performance were identified as the main predictors of gamification on brand attitude. Furthermore, social interaction is a key factor for the success of game systems, which should promote interaction between communities of players to share functionality and solve task problems. It was observed that attitude towards the brand is positively influenced by factors such as usefulness, perceived ease of use, social influence, intention to get involved, and gamification of performance, especially when these are mediated by the sensation of pleasure. This finding points to the importance of these elements in shaping consumers’ perceptions of brands. To maximize engagement with brands, gamification tools should allow sharing content and tasks, promoting discussions and broadening the connection between the gamers community. It is important to consider technological resources and innovation in the design of gamification tools, as well as to meet the different expectations of consumers, allowing different tasks and high connection between different information-sharing channels. This study contributes to the development of knowledge in gamification on brand attitude. Practical implications have been suggested to guide companies in implementing a successful gamified marketing strategy.

Modelling and Optimization of Banana/Plantain Fiber Extraction Systems through Dimensional Analysis

This study presents a comprehensive parametric modelling approach for a locally produced plantain and banana fiber extractor, utilizing the Buckingham Pi theorem to analyze the complex interactions among various operational parameters. Plantain and banana fibers are increasingly recognized for their diverse industrial applications, including textiles, paper, packaging, and food supplements. The mechanical extraction of these fibers is prevalent, necessitating a well-designed process that conserves the natural properties of the fibers while maximizing cost-effectiveness. This research aims to optimize the design and operational parameters of the extractor to enhance its extraction capacity and overall efficiency. Employing the Buckingham Pi theorem, the study constructs dimensionless Pi terms from key parameters impacting the extractor's performance. The analysis reveals a coefficient of correlation (R²) of 0.9923 for extraction efficiency and 0.9867 for extraction capacity, indicating a strong predictive capability of the developed model. These findings provide valuable insights into optimizing the performance of the plantain and banana fiber extractor, ultimately contributing to more efficient and sustainable fiber extraction processes. This model serves as a critical tool for designers and manufacturers aiming to improve the economic viability of fiber extraction systems.

Damage analysis and optimal design of micro-structure milling cutter based on peridynamics.

H13 die steel has the characteristics of high hardness, strong toughness, and good heat resistance, and is a typical difficult to process materials material. During the cutting process, it is prone to accelerate tool wear and cause thermal deformation. By reasonably designing micro-grooves, the comprehensive performance of the tool can be effectively improved. In this study, by optimizing the structural parameters of the micro-groove, the comprehensive performance of the tool is significantly improved, and the micro-groove optimization control mechanism is deeply analyzed. At the same time, the micro-damage problem is numerically analyzed by using the peridynamics numerical simulation and comparison experiment. Research results indicate that properly increasing the distance between the slot at the outer contour of the cutting tool and the cutting edge and projecting it in a flattened shape onto the surface of the tool, ensures a smooth transition between the groove top and bottom near the cutting edge can effectively enhance the comprehensive performance of the cutting tool. The tool's major cutting edge near-field and rake face is prone to micro-cracks resulting in crack diffusion. When the milling time is 3.5×10-6 s, the tool's major cutting edge combined displacement increases most rapidly, the major flank optimization effect is the most obvious, and the resultant displacement is reduced by about 37.06%. By optimizing the structural parameters of micro-grooves on the rake face, this study enhances the comprehensive performance of the tool and unveils the formation, distribution, and variation patterns of near-field cracks on the tool's cutting edge. The research results have certain valuable insights for the optimization design and manufacturing of high performance milling tools made from H13 die steel.

A Geometrical Speculation. The Twelfth Century Roof and some Peculiar Aspects of the Ground Plan of Værnes Church, Norway

The following is an exercise in what may seem an old-fashioned art, popular among architects in the nineteenth and early twentieth centuries, but later somewhat discredited – the search for geometrical patterns underlying medieval church design. However, the interest in mathematically based tools for design of historic buildings has in recent years been revived, proof of which is a steadily increasing flow of publications reporting scientifically rigorous studies. My contribution concerns the church at Værnes, near Trondhei, Norway, and the impressive open truss timber roof of the nave. Not being content with previous suggestions on how the roof design might have been determined, I compared it to similar structures in the region and found several cases of the same ratio of width to height. I also noted that this ratio corresponded almost exactly to a simple geometrical diagram, which further led me to make some assumptions on how Værnes church was originally planned.

Digital Prototyping and Regenerative Design Toward Carbon-Neutrality and a Climate Resilient Built Environment: A Multi-Scale Assessment of Environmental Multi-Risks

This study addresses the urgent need to move the construction sector toward carbon neutrality and climate resilience, by considering the increasingly intense impacts of climate change. The research aims to evaluate the application of advanced digital prototyping tools and regenerative design principles to identify environmental risks at different scales, with a particular focus on cultural and natural heritage. The hypothesis is that the integration of climate data and predictive models with regenerative design can overcome existing barriers to sustainable practices and significantly enhance the adaptive capacity of the built environment, particularly in safeguarding cultural and natural heritage against the multi-hazard impacts of climate change. To test this hypothesis, an experimental study is conducted using a combination of climate data, advanced modeling and regenerative design tools to assess and manage multi-hazard impacts on cultural and natural heritage. Two case studies were analyzed: Palizzi Marina, a coastal town vulnerable to sea level rise and flooding, and Palazzo Mesiani in Bova, a historic building exposed to increased solar radiation and temperatures. This type of analysis has enabled a comprehensive multi-scenario and multi-hazard assessment that offers a detailed overview of the risks to be considered in the design phase. In conclusion, the research underscores the importance of interdisciplinary approaches and emerging technologies in resilient design frameworks. By integrating climate data and predictive models with regenerative design methodologies, this study can significantly contribute to enhancing the adaptive capacity of the built environment. This approach aids in the transition of the construction sector toward sustainability and climate resilience, particularly in protecting cultural and natural heritage.

Latent Thermal Energy Storage for Cooling Demands in Battery Electric Vehicles: Development of a Dimensionless Model for the Identification of Effective Heat-Transferring Structures

Thermal energy storage (TES) systems open up alternative paths for air conditioning to increase the range of battery electric vehicles (BEVs) by reducing power consumption. The central prerequisites for this purpose are high storage densities: high-temperature TES systems are being focused on for heat demands, while effective solutions for cooling are missing. Due to their lower temperature potentials, concepts with high storage capacities and heat transports between the storage and cold transferring medium are needed. Latent TES systems based on water enable these capacities but require adequate internal structures for effective heat transfer. Due to the large number of geometric options, high simulation efforts must be conducted to identify favored structures, or the possible design space must be limited for investigations. For this purpose and for the first time, an alternative way is presented using newly developed dimensionless models in a top-down methodology for time-efficient design studies and evaluations. These models were successfully validated and used as a design tool to identify effective structures in latent TES systems for cooling demands in BEVs. A wide array of variation studies on tube, finned plate and novel Triply Periodic Minimal Surface (TPMS) structures were performed and uniformly evaluated with regard to storage densities, cooling efficiencies and geometry. The results show high storage densities for novel TPMS structures, including the enclosure of 100 Wh/kg or 102.2 kWh/m3 with average cooling capacities of 1 kW over 30 min, confirming the usability of latent TES systems in terms of compactness and efficiency for cooling demands in BEVs.

Type synthesis, analysis, and prototyping of 4R1H mechanisms

Abstract The article introduces a novel class of 4R1H mechanisms, where 4R indicates four revolute joints and 1H indicates one helical joint. The paper starts with the type synthesis of these mechanisms, which involves combining two kinematic chains with planar and cylindrical motion types into a single closed-loop kinematic chain. If we fix any link in such a chain, we get a workable mechanism. The synthesis procedure considers two options for the relative arrangement of these two kinematic chains. Adding an H joint to the kinematic chain allows us to design mechanisms whose output link performs spatial motion. Using the proposed synthesis procedure, we develop a family of 4R1H mechanisms. Next, we choose one mechanism as a representative example and consider its mobility, singularity, kinematic, and dynamic analysis. Using screw theory, we confirm the mechanism has one degree of freedom and determine its singular configurations. Kinematic analysis provides closed-form expressions to calculate displacements, velocities, and accelerations of all the mechanism links. Dynamic analysis uses these results to compute the motor torque required for one motion cycle. To verify the suggested analytical algorithms and obtained results, we use computer-aided design tools, which allow us to develop virtual and physical prototypes.

Integrated Dynamic Analysis of Thin-Walled Beams: Coupled Bidirectional Bending, Torsion, and Axial Vibrations Under Axial Loads

This paper proposes a beam model integrating the Timoshenko beam theory with Vlasov beam theory to capture the coupled behavior of bidirectional bending, torsion, and axial vibration in thin-walled beams subjected to axial loads. Our model incorporates the effects of shear deformation, rotational inertia, and axial loads, offering a comprehensive approach to complex dynamic behaviors. By utilizing Hamilton’s principle, we derived a complete set of coupled dynamic equations and boundary conditions. The highlight of this model is its capacity to accurately predict the dynamic response of thin-walled beams under multifaceted loading conditions, surpassing traditional models by integrating coupled axial vibrations. This research significantly advances the understanding of the dynamic behavior of thin-walled beams, providing a precise analytical tool for structural design and safety assessment. The robustness and accuracy of the proposed model were validated through extensive theoretical analysis and empirical validation, equipping engineers with critical insights to optimize the design of engineering structures subjected to complex dynamic loads.

Power-Assisted Scissors Reduce Adductor Pollicis Muscle Fatigue: A Comparative Study in Female College Students

Hand fatigue commonly occurs in repetitive tasks, such as cutting with scissors, leading to discomfort, reduced productivity, and musculoskeletal disorders. Recent advances in assistive technology have introduced power-assisted scissors to reduce the muscular load. Pinching and grasping mainly involve the adductor pollicis muscles of the hand. Measuring the electromyographic (EMG) activity of these muscles provides valuable insights into the muscular effort required for such tasks. Studies have indicated that power-assisted devices can effectively reduce muscle strain and fatigue. However, research on the effect of power-assisted scissors on adductor pollicis muscle activity is limited. This study examines the differences in adductor pollicis muscle activity using power-assisted scissors versus traditional scissors. The experiment consisted of 20 participants performing a scissor manipulation task with and without power assistance. Frequency analysis of the adductor pollicis muscle EMG data indicated that scissors with power assistance significantly reduced muscle fatigue (95% confidence interval, 10.705 [4.523–19.751], p < 0.01, η2 = 0.01). Understanding the efficacy of power-assisted scissors has significant implications for occupational health—particularly in professions that involve extensive manual cutting, such as tailoring and hairdressing. This study can contribute to the design of ergonomic tools that enhance comfort and reduce musculoskeletal disorder risks.

Guiding Competitive Binding Assays Using Protein-Protein Interaction Prediction: The HER2-Affitin Use Case.

Affitins are a class of small artificial proteins, designed as alternatives to antibodies for therapeutic, diagnostic, and biotechnological applications. Recent patents by Bracco Imaging S.p.A have demonstrated the potential of two engineered affitins for designing imaging probes to detect and monitor human epidermal growth-factor receptor 2 (HER2) levels in vivo. Targeting HER2 is critical, as its overexpression is linked to poor prognosis of several cancer diseases, making it a key marker for treatment strategies and diagnostic tools. Interestingly, these affitins do not compete with the commonly used monoclonal antibodies trastuzumab and pertuzumab for HER2 binding sites, allowing their concurrent use in vivo and making them suitable for imaging or diagnostic purposes. Since these two affitins compete for the same yet unidentified binding site on HER2, structural insights into these interactions are essential for facilitating the design and development of more effective diagnostic tools and treatments. In this study, we used protein-protein docking and molecular dynamics simulations to model the binding of these affitins to HER2. The stability of the predicted complexes was quantified by using the DockQ parameter, a widely used metric for evaluating protein-protein docking predictions. The docking poses were then compared with HER2 sites likely to interact with a protein partner, as predicted by the matrix of local coupling energies method. The combination of these two computational methods allowed for the identification of the most likely docking poses. Comparative analysis with HER2-protein complexes from the Protein Data Bank suggests that both affitins may bind HER2 at the same epitopes as an antibody fragment and an affibody. These findings indicate that targeted competitive binding assays could efficiently reduce the experimental efforts to map the HER2-affitin interactions. The computational approach proposed in this study not only provides insights into this specific case but also establishes a robust framework applicable for facilitating the structural modeling and interaction prediction of other affitin-protein systems.

Process Parameters and Tool Design in Friction Stir Extrusion: A Sustainable Recycling Technique

ABSTRACTFriction stir extrusion (FSE) is a versatile technique that plays a dual role in sustainable recycling and shaping of materials. This method involves a rotating mandrel and a fixed matrix within a mold, where compressed waste metal chips or primary bulk materials are introduced. The rotating mandrel exerts continuous axial pressure, generating frictional heat that softens and bonds the materials together. As the mandrel advances, the materials are reshaped and extruded through the cavity inside the mandrel or the space between the mandrel and the matrix, resulting in the desired product, such as wires or pipes. FSE finds applications in recycling machining wastes, improving powder metallurgy products, producing wire raw materials, creating structures with fine microstructures, and developing new alloys and composites. The resulting materials exhibit refined grains, leading to enhanced mechanical and metallurgical properties. This review article compiles experimental studies exploring the mechanical and microstructural characteristics of samples manufactured using FSE for recycling, reshaping, alloying, or bilayer production. Additionally, it discusses various tool, mold, and machine designs proposed by researchers. Beyond its unique properties, FSE is highlighted as an energy‐efficient, sustainable, and eco‐friendly process.

Life-cycle assessment tools for road design: analysing linearity assumptions

Road infrastructure significantly impacts how people move, live, and the emissions associated with travel behaviour. The design of roads is crucial in mitigating emissions. This paper reviews existing transport Life-Cycle Assessment tools that have been developed by various entities and can be used for roads. The review focuses on several aspects in terms of data sources used in the analysis, the methods of estimating carbon emissions, the underlying software that is used to make the estimates and any limitations of the tools. A critical issue identified in Life-Cycle Assessment analysis is the erroneous assumption that relationships within the assessed systems are linear. The current tools focusing on transport infrastructure assessment were developed based on the linear assumptions and limitations of the Life-Cycle Assessment analysis. A significant research gap identified is that existing Life-Cycle Assessment tools are not integrated with the design process. The analysis is an add-on process to design and the results of an assessment are not then used iteratively to enhance the design. A case study on aggregate road design found that road area significantly correlates with emissions, slope adjustments reduce emissions, and soil type impacts emissions, suggesting future research should explore nonlinear relationships for sustainable road design.

Temperature and pH Effects on High-Methane Biogas Production

Objective: Biomass is a renewable, widely available, and economically viable energy source for use in anaerobic digestion processes to produce biogas and methane (CH₄). To harness this potential, various technologies have been improved to better reuse organic waste, such as those from the agroindustry, to generate renewable energy and also to contribute to minimizing the environmental risks caused by the improper disposal of these materials. The objective of this study was to define the best operational conditions for the production of biogas and CH₄ from the anaerobic co-digestion of bovine manure, cassava wastewater, and coffee husk. Methods: All tests showed significant biogas production with at least 80% methane. The statistical tool of experimental design made it possible to identify an inversely proportional relationship between pH and temperature, within the conditions analyzed for these factors. Results: Thus, it was defined that the combination of an initial pH above 9.5 and a temperature below 35 °C is capable of resulting in a biogas volume > 600 cm³ and CH₄ > 500 cm³. For example, the best experimental performance was obtained with an initial pH of 10.0 and a temperature of 30 °C, which resulted in 798.72 cm³ of biogas and 638.98 cm³ of CH₄ accumulated after 15 days of hydraulic retention time. These best experimental conditions enabled 58.53% removal of chemical oxygen demand and a final pH close to neutrality (6.3). Conclusion: This represents good fermentation conditions for methanogenic bacteria and confirms the feasibility of using co-digestion of the three evaluated residues.

Effects of Out-of-Plane Deformation of the Base Plate on the Structural Behavior of an Exposed Column Base

This study explores the behavior of exposed column bases in concrete-filled steel tubular (CFST) and steel structures, with a focus on cases where base plates yield due to out-of-plane deformation. Understanding these mechanisms is crucial for improving the design and safety of these structures. Experimental tests and numerical analyses were conducted on four specimens to investigate their lateral load versus drift angle behavior. The tests demonstrated that base plates exhibited sufficient deformation capacities and enhanced hysteresis characteristics. Finite element method (FEM) analysis successfully traced the load–deformation relationships observed in the tests, providing detailed insights into stress distribution on the base plates. Based on these analyses, a simplified calculation method was proposed to evaluate the horizontal strength of exposed column bases. The proposed method showed excellent agreement with the test results, highlighting its potential as a practical tool for structural design.

The effects of stress on surgical performance: a systematic review.

Acute stress, the psychological response to short-term challenging stimuli, is frequently encountered in the high-pressure environment of the operating theatre. Surgeon stress is associated with deterioration in surgical performance, surgical team working and compromised patient safety. Given these concerns, the aim of this review was to understand the impact of acute stress on surgical performance in technical and non-technical domains as well as patient outcomes. A systematic review was conducted following PRISMA guidelines. Electronic databases were searched for studies examining acute stress in medical professionals during real or simulated surgical procedures that reported performance outcomes in technical and non-technical skills. Risk of bias assessment was conducted using appropriate tools for each study design. Out of 1445 identified studies, 19 met the inclusion criteria. In simulated environments, acute stress consistently led to impairment in both technical and non-technical skills during surgical procedures. Technical skill deterioration included higher procedural error rates, longer task completion times and diminished instrument handling. Non-technical skills, such as teamwork and communication, also were impaired under stress conditions. Real-world studies echoed these findings, demonstrating acute stress resulting in higher error rates and impaired non-technical skills. No studies identified surgeon stress as having a causal relationship with patient outcomes. Acute stress significantly impacts both technical and non-technical skills during surgical procedures, impairing performance in simulated and real-world surgical environments. Despite the growing understanding of the detrimental effects of stress, gaps remain in comprehensively assessing its impact on patient outcomes. Further research is warranted to develop reliable stress measurement methods applicable in surgical settings and explore effective stress management strategies.

Structure-optimized sgRNA selection with PlatinumCRISPr for efficient Cas9 generation of knockouts.

A single guide RNA (sgRNA) directs Cas9 nuclease for gene-specific scission of double-stranded DNA. High Cas9 activity is essential for efficient gene editing to generate gene deletions and gene replacements by homologous recombination. However, cleavage efficiency is below 50% for more than half of randomly selected sgRNA sequences in human cell culture screens or model organisms. We used in vitro assays to determine intrinsic molecular parameters for maximal sgRNA activity including correct folding of sgRNAs and Cas9 structural information. From the comparison of over 10 data sets, we find major constraints in sgRNA design originating from defective secondary structure of the sgRNA, sequence context of the seed region, GC context, and detrimental motifs, but we also find considerable variation among different prediction tools when applied to different data sets. To aid selection of efficient sgRNAs, we developed web-based PlatinumCRISPr, an sgRNA design tool to evaluate base-pairing and sequence composition parameters for optimal design of highly efficient sgRNAs for Cas9 genome editing. We applied this tool to select sgRNAs to efficiently generate gene deletions in Drosophila Ythdc1 and Ythdf, that bind to N 6 methylated adenosines (m6A) in mRNA. However, we discovered that generating small deletions with sgRNAs and Cas9 leads to ectopic reinsertion of the deleted DNA fragment elsewhere in the genome. These insertions can be removed by standard genetic recombination and chromosome exchange. These new insights into sgRNA design and the mechanisms of CRISPR-Cas9 genome editing advance the efficient use of this technique for safer applications in humans.

Type synthesis of a new class of 4-3T1R(y) parallel mechanisms for parallel machine tools design

Unlike previous design procedures for parallel machine tools (PMTs), this paper first analyzes the path and posture requirements of the tools in universal processing, then proposes and constructs a new class of PMs that can provide the required path and posture. This opens up new ideas for the design of PMTs. Based on the reciprocal screw theory, a type synthesis process of asymmetrical lower-mobility PMs was proposed. Through this process, a novel class of four-limbed parallel mechanisms (PMs) providing three translations and one rotation around a horizontal axis (y-axis), denoted as 4-3T1R(y) PMs, was successfully proposed and constructed. Such PMs can be applied to the design of PMTs, especially the design of micro-electrical discharge machining (micro-EDM) PMTs. The structural design of a new 2RRC-2CRU PM, which was a member of 4-3T1R(y) PMs, was performed, and its mobility was analyzed in detail to demonstrate the efficiency of the proposed type synthesis process. The inverse, forward, and velocity kinematics problems of the 2RRC-2CRU PM were solved for further applications.

Control Intracellular Protein Condensates with Light.

Protein phase transitions are gaining traction among biologists for their wide-ranging roles in biological regulation. However, achieving precise control over these phenomena in vivo remains a formidable task. Optogenetic techniques present us with a potential means to control protein phase behavior with spatiotemporal precision. This review delves into the design of optogenetic tools, particularly those aimed at manipulating protein phase transitions in complex biological systems. We begin by discussing the pivotal roles of subcellular phase transitions in physiological and pathological processes. Subsequently, we offer a thorough examination of the evolution of optogenetic tools and their applications in regulating these protein phase behaviors. Furthermore, we highlight the tailored design of optogenetic tools for controlling protein phase transitions and the construction of synthetic condensates using these innovative techniques. In the long run, the development of optogenetic tools not only holds the potential to elucidate the roles of protein phase transitions in various physiological processes but also to antagonize pathological ones to reinstate cellular homeostasis, thus bringing about novel therapeutic strategies. The integration of optogenetic techniques into the study of protein phase transitions represents a significant step forward in our understanding and manipulation of biology at the subcellular level.

Exploring the Modelling of Gold Anisotropic Nanoparticles’ Optical Properties as a Promising Tool for Detection Systems Design

Gold nanoparticles have been a central topic in the last few decades due to their excellent optical properties that can be exploited in many applications, including food analysis, materials science, and biomedicine. The basis of these unique optical properties is the phenomenon known as localized surface plasmon (LSP), which relays in the collective oscillation of the conduction band electrons in the nanoparticle when excited by electromagnetic radiation. The optical properties of the nanoparticles are critical for selecting the best nanomaterials for each application, a key factor for optimum performance, and can be tuned due to their dependence on the geometry and size of the nanoparticles, as well as the polarization of the light beam. Here, we conducted simulations to study the tunable optical properties and local electric field distribution of three types of gold nanoparticles, cubes (AuNC), boxes (AuNB), and triangular prisms (AuNT), which have relatively simple synthetic routes. Finally, we compared these results with experimental data and described possible synthetic routes to discuss the positive and negative aspects of using each type of nanoparticle for potential applications.