Design Methodology Research Articles

An efficient floating point adder for low-power devices

With an increasing demand for power hungry data intensive computing, design methodologies with low power consumption are increasingly gaining prominence in the industry. Most of the systems operate on critical and noncritical data both. An attempt to generate a precision result results in excessive power consumption and results in a slower system. An attempt to generate a precision result results in excessive power consumption and results in a slower system. For non-critical data, approximate computing circuits significantly reduce the circuit complexity and hence power consumption. For non-critical data, approximate computing circuits significantly reduce the circuit complexity and hence power consumption. In this paper, a novel approximate single precision floating point adder is proposed with an approximate mantissa adder. The mantissa adder is designed with three 8-bit full adder blocks.

Communicating educational innovation projects in Latin America mediated by the scaling of complex thinking: Contribution of the UNESCO-ICDE Chair in Mexico

The United Nations Educational, Scientific and Cultural Organization (UNESCO) Chair in the open educational movement for Latin America aims to promote scientific, technological, entrepreneurial, and innovative development. In Mexico, face-to-face bootcamps occur every two years, where prototypes of high-value solutions for education are developed using design and active learning methodologies, with the aim of scaling complex thinking and sustainable development. In the 2023 edition, 94 academicians from 12 countries participated (Argentina, Bolivia, Chile, Colombia, Ecuador, Germany, Guatemala, Mexico, Peru, Spain, the Dominican Republic, and the United Kingdom). Experts from Tecnológico de Monterrey, the Open University, the University of Leeds, and Siemens Stiftung supervised the process. This article presents the prototyped proposals and the results of applying the Play2Train4C methodology, enabling participants to develop educational innovation projects under the paradigm of complex thinking. The results indicate that (1) the participants managed to prototype ten proposals validated by experts and (2) their perceptions of their systemic, critical, scientific, and innovative thinking (sub-competencies of complex thinking) improved by the end of the bootcamp. The conclusion was that the UNESCO Chair boosted solution-building skills for the complex problems arising in Latin America and enabled key agents in education to improve their complex thinking skills for quality education, as promulgated by sustainable development goal 4.

The temporal dynamics of daily stress, affect, and several affect regulation processes, in patients with chronic mood and anxiety disorders before and after a mindful yoga intervention

Background and ObjectivesPatients with chronic mood and anxiety disorders experience many life stressors and are more reactive to these stressors. Although mindful yoga might reduce stress reactivity, little is known about the affect regulation mechanisms involved, such as repetitive negative thinking, fear of emotion, acting with awareness and body awareness. Design and MethodsUsing experience sampling methodology, 12 patients with chronic mood and anxiety disorders completed five daily assessments for 15 days before and after a 9-week mindful yoga intervention. Interrupted time-series analyses were used to assess mean-level change from pre-to-post intervention and vector autoregressive models to assess change in the temporal associations. ResultsMost individuals experienced positive changes in affect and the proposed affect regulation processes. Fear of emotion showed changes from pre-to-post intervention for most individuals (67%), followed by acting with awareness (58%), body awareness (58%) and repetitive negative thinking (50%). In the dynamic relationships between stressors, the four affect regulation processes and affect, there were individual differences in which pathways changed and how they changed. ConclusionsAfter a mindful yoga intervention, affect and several affect regulation processes improve in most individuals. Achieving this in the context of daily life stress, seems to be more complicated. Trial registrationISRCTN register (study ID ISRCTN13612864).

Antimicrobial Effect of Response Surface Optimized Pyocyanin Produced by Pseudomonas aeruginosa

Pseudomonas aeruginosa is notable for its natural bluish-green pigment production, known as pyocyanin. Researchers have credited pyocyanin as an antimicrobial agent, in addition to its other biomedical applications. This study focused on isolating Pseudomonas aeruginosa from the local environment with the ability to synthesize pyocyanin and optimize its cultural conditions for improved yield. A total of thirty-one experimental combinations of process variables using the Central Composite Design (CCD) of Response Surface Methodology (RSM) was ran to find the best conditions for the organism to make pigments. Of the fermentation media evaluated, nutrient broth supplemented with maltose was the best fermentation medium for the organism’s pyocyanin production. A regression model described the interaction between the test variables and the pyocyanin yield with an R2 value of 87.52%, indicating that the model had a satisfactory fitness level. The determined optimal conditions include a maltose concentration of 18 g/L, a pH of 6.8, an inoculum size of 2.3 mL, and an agitation speed of 120 rpm. The optimized condition resulted in a 4.12-fold increase in pyocyanin yield compared to an unoptimized condition. Pyocyanin exhibits high antimicrobial activity compared to the conventional antibiotics assessed against E. coli and Candida albicans. Our study’s findings suggest that statistical models can improve pyocyanin synthesis by Pseudomonas aeruginosa. Furthermore, this pigment has the potential to replace conventional antibiotics in the treatment of microbial infections

Application of Scheffe's Simplex Lattice Model in concrete mixture design and performance enhancement

This comprehensive literature review delves into the application of Scheffe's Simplex Lattice Model for optimizing cement concrete mixtures, with a particular emphasis on its impact on material properties and sustainability. The review meticulously outlines the principles, historical context, and advantages of Scheffe's model, providing a nuanced understanding of its significance. Comparative analyses with traditional and alternative optimization techniques in concrete mix design illuminate the distinct advantages of statistical methods, especially Scheffe's model. The review critically examines the challenges and limitations associated with applying Scheffe's model, addressing issues related to the complexity of concrete mixtures and computational demands. Potential avenues for improvement are explored, suggesting refinements to handle non-linearity, incorporate advanced optimization algorithms, and streamline computational requirements. Additionally, the review highlights emerging trends in statistical modeling for concrete mixture optimization, such as the integration of machine learning and data-driven approaches, signaling the evolving landscape of concrete technology. In conclusion, the literature underscores Scheffe's Simplex Lattice Model as a valuable and versatile tool with far-reaching implications for the advancement of concrete mixture design methodologies. The call to action encourages ongoing research and development to refine the model, explore emerging trends, and address practical challenges, positioning Scheffe's model as a cornerstone in the pursuit of sustainable, resilient, and high-performance concrete materials. The study highlights Scheffe's Simplex Lattice Model as a robust statistical tool for optimizing cement concrete mixtures, demonstrating its efficacy in improving performance indicators like compressive strength and durability. This systematic approach offers a paradigm shift from empirical methods, fostering a nuanced understanding of concrete components' relationships and paving the way for tailored material properties and enhanced sustainability in construction. The call to action urges further research to refine the model, address challenges, and explore hybrid approaches, ultimately advancing concrete mixture design methodologies towards greater efficiency and precision.

ENHANCING 21ST CENTURY SKILLS THROUGH INTEGRATED STEM EDUCATION USING PROJECT-ORIENTED PROBLEM-BASED LEARNING

In the pursuit of comprehensive education, the symbiotic relationship between 21st-century skills and STEM is crucial. These two domains work hand in hand to equip students with the knowledge and abilities required to thrive as productive and technically literate citizens in the future. This study assessed the impact of an integrated STEM education program on students' 21st-century skills using Project-Oriented Problem-Based Learning (PoPBL) as the core pedagogical approach. A onegroup quasi-experimental design and survey methodology were employed to evaluate students' skills before and after participating in the program. The findings showed a significant increase in students' overall 21st-century skills, with high productivity skills notably improving from moderate to high proficiency. These results provide compelling evidence that PoPBL in STEM education effectively enhances students' skills by immersing them in authentic, real-life problem-solving experiences through project work. The study emphasizes the value of integrating PoPBL into STEM education to enhance critical skills such as problemsolving, creative thinking, collaboration, and effective communication. By engaging in practical, project-based activities, students not only apply their knowledge but also develop competencies to address complex challenges in their future endeavors.

Contributions of the Ondas Program of Colombia in the training of researchers

Article resulting from research on the contribution of the Ondas Program in the training of children, young people, graduates and research teachers of official educational institutions in the urban area of the municipality of Palmira (2014-2018); with mixed methodology, non-experimental descriptive, transversal and retrospective design, in a sample of students, teachers and graduates of I.E. urban public utilities in Palmira linked to the Ondas program between 2014-2018; updated information with evidence from recent years. A matrix of indicators and a semi-structured online form questionnaire are used as instruments. In findings, the Ondas program has positive results in the training of children, young people, graduates and research teachers, the longer the time of participation in the program, the greater the effect over time, improving academic level and preference for careers related to S&T. Concluding that the promotion of scientific vocations through the Ondas program demonstrates the achievement of its objectives.

The Playful Karoo: Translating a South African Story into the Metaverse

ABSTRACT This research paper explores different game design methodologies that can be used to translate the South African novel Souvenir by Jane Rosenthal, set in the semi-desert region known as the Karoo into a Virtual Reality experience, which can live on the Metaverse. The paper suggests that the translated Virtual Reality experience can be used as a tool for climate change action and awareness, as well as a way to preserve South African stories on the Metaverse. The paper focuses on various narrative design methodologies for storytelling in game design, suggesting which would work best for the translation of a novel into a Virtual Reality experience. Additionally, it explores practical methodologies for the production of 3D game objects and assets required to recreate the Karoo landscape as described in the novel. This encompasses an exploratory excursion conducted within the Karoo region itself, wherein the collection of primary data is executed for the creation of game assets. Additionally, this involves a comprehensive examination of Henry Jenkins’ methodologies in game design, particularly focusing on narrative elements within gaming. A meaningful impact on the Metaverse is pursued through the translation of this Karoo-based South African novel, into Virtual Reality.

Geotextile filters: from idealization to real behaviour (Giroud Lecture 2023)

Geotextiles have been used as filters in geotechnical and geoenvironmental works for decades. Despite their broad utilization, these filters still find obstacles to the expansion of their application in larger projects and under complex soil and flow conditions. However, environmental issues are increasingly pressing for a greater use of geotextile filters in substitution to natural granular materials. Even though many important studies in the literature have improved the understanding of soil-fluid-geotextile filter interaction, some issues still require thorough investigation aiming at a better understanding of the behaviour of geotextile filters and the development of better design methodologies. This paper discusses how geotextiles filters are expected to behave in the field and some contradictions between idealized and real behaviour. Concerns regarding the use of geotextile filters under severe and critical conditions and how filter malfunction can be avoided or minimised are also addressed as well as approaches available to predict filter behaviour. A broad investigation on geotextile filter behaviour under severe and critical conditions was carried out and shows that these filters have been very successful, particularly bearing in mind the small number of failures in comparison with the huge number of applications of geotextile filters.

Design of advanced dielectric RF windows for dual-band Gyro-TWT

In this paper, the design of different dielectric advanced ceramic materials of RF windows for dual-band K-band and Q-band Gyro-TWT has been described. The design methodology of quartz, magnesium aluminate (MgAl2O4) and sapphire dielectric windows of operating TE01 mode for K-band and Q-band Gyro-TWT has been discussed. The simulation result predicts that these windows can handle 100 kW output power and return loss −58.5 dB and insertion loss −0.02 dB. This paper presents the electrical design and thermal analysis of K-band and Q-band dual-band Gyro-TWT amplifier. In the thermal analysis, the maximum temperature has been obtained at the centre of the dielectric disc. The electro-mechanical analysis has also been carried out on the different dielectric windows to achieve stress and displacement. A new type and unique advance transparent dielectric material magnesium aluminate (MgAl2O4) disc window has been used to improve the bandwidth performance of Gyro-TWT.

Optimization and Modeling of a Dual-Chamber Microbial Fuel Cell (DCMFC) for Industrial Wastewater Treatment: A Box–Behnken Design Approach

Microbial fuel cells (MFCs) have garnered significant attention due to their capacity to generate electricity using renewable and carbon-neutral energy sources such as wastewater. Extensive experimental work and modeling techniques have been employed to dissect these processes and understand their respective impacts on electricity generation. The driving force is to enhance MFC performance for practical applications commercially. Among the various statistical modeling approaches, one particularly robust tool is the Design of Experiments (DoE). It serves to establish the relationships between different variables that influence MFC performance and allows for the optimization of the MFC configuration and operation for scaled-up performances in terms of bioelectricity generation. This study focused on optimizing microbial fuel cells (MFCs) for bioelectricity production using industrial wastewater treatment, employing the Box–Behnken design (BBD) methodology. Through an analysis of response surface models and ANOVA tests, it was found that a combined approach of reduced quadratic, reduced two-factor interaction, and linear models yielded sound results, particularly in voltage yield, COD removal, and current density. Second-order regression models predicted optimal conditions for various parameters, with surface area, temperature, and catholyte dosage identified as critical input variables for optimization. Under these conditions, conducted by the four-factor and three-level Box–Behnken design methodology in a double-chamber MFC unit considering eight output variables—CCV yield, % COD removal, current density, power density, % TSS removal, % CE, and % PO43−—the optimum values were 700 mV, 54.4%, 54.4 mA/m2, 73.7 mW/m2, 99%, 21.2%, and 100%, respectively. At optimum operating conditions, the results revealed a desirability of 76.6% out of a total of 92 iterations. The paper highlights the effectiveness of statistical ANOVA fit-statistics modeling and optimization in enhancing DCMFC performance, recommending its use as a sustainable bioenergy source. Furthermore, validation results supported the above optimization output response findings and confirmed the viability of biorefinery wastewater as an anolyte for scaling up DCMFC bioelectricity generation.

Exploring Perspectives: The Role of Educational Technologies in Improving the Teachers’ Pedagogical Aspect

The aim of this research is to examine the role of using new educational technologies in improving teachers’ pedagogical aspect. Even though various studies have been conducted on the role of technology in teaching, the pedagogical aspect and its im-provement through the use of educational technologies was not explored to date. Therefore, the lack of research on these variables was a motivation to conduct such a study. Through literature review, the advantages and disadvantages of using educational technologies in the pedagogical aspect during the teaching process are described. This research included 83 lower secondary school teachers from the municipality of Prishtina. The research used mixed methodology, including both qualitative and quan-titative designs. The research questions are: P1: What role does the use of new educational technologies play in improving the pedagogical aspect for teachers? Which was answered through inferential analysis. This shows that the use of new educational technologies plays a positive role in the pedagogical aspect for teachers. P2: What new educational technologies are used by teachers during the teaching process? This question was answered through descriptive analysis. These responses highlighted a positive role of integrating new educational technologies in improving the pedagogical aspect for teachers, making teaching more attractive and enabling greater clarification of new information for students during the lesson.

AN IN-DEPTH EXPLORATION OF BHIL ART-INSPIRED DESIGN IN CONTEMPORARY TEXTILE PRODUCTS

Known for the intricate motifs, vibrant colors, and deep cultural symbolism, Bhil art is the cultural heritage of the Bhil tribe in India. This paper presents an in-depth study of Bhil art- inspired designs in contemporary textile products. The study also explores the adaptation of traditional artistic elements into modern textile design, exploring the synergy between heritage and innovation. Emphasizing a qualitative approach, the research delves into the cultural nuances embedded in Bhil artistry and examines how these elements are translated into textile products through innovative design methodologies. The focus of the paper is to contribute to the discourse on the preservation of cultural heritage in the context of evolving design practices. This study not only sheds light on the artistic evolution but also addresses the ethical considerations and challenges in preserving the authenticity of Bhil culture amidst modern design processes. The primary findings contribute to a full consideration of the active chemistry between cultural heritage and the ever-evolving area of textile product design.

A Comprehensive Approach for Designing Low Carbon Wood Bio-Concretes.

This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed by using the traditional design rules used for conventional mortar or concrete. Then, the method used in the current paper is an adaptation of a previous one that has been developed in a recent paper where bio-concretes were produced with a cement matrix, three types of bio-aggregates, and a proposal of a design abacus. However, when that abacus is used for designing WBC with low cement content in the matrix, the target compressive strength is not reached. In the present paper, the method is extended to low cement content matrix (up to 70% of cement substitution) and also considering the greenhouse gas (GHG) emission of the WBC. To obtain data for proposing a new design abacus, an experimental program was carried out by producing nine workable WBCs, varying wood volumetric fractions (40-45-50%), and water-to-binder ratios. The bio-concretes produced presented adequate consistency, lightness (density between 715 and 1207 kg/m3), and compressive strength ranging from 0.64 to 12.27 MPa. In addition, the GHG emissions of the WBC were analysed through the Life Cycle Assessment methodology. From the relationships obtained between density, compressive strength, water-to-binder ratio, cement consumption, and GHG emissions of the WBC, calibration constants were proposed for developing the updated and more complete abacus regarding an integrated mix design methodology.

The relationships of inflammatory blood markers with maternal periodontal and dental states and their effects on preterm membrane rupture development

BackgroundThe influence of maternal oral and dental health on the occurrence of Preterm Premature Rupture of Membranes (P-PROM) and its underlying mechanisms remain uncertain. This research seeks to investigate the impact of maternal oral and dental health on the incidence of P-PROM and its association with inflammatory markers in the blood.MethodsThis study adopts a prospective case-control design methodology. The study involved 70 women diagnosed with P-PROM and delivered by an obstetrician and 79 women who had healthy deliveries with no prenatal complications. The values for DMFT (Number of decayed, missing and filled teeth) index, Gingival Index (GI), Plaque index (PI), Pocket depth (PD), Clinical attachment loss (CAL) and medical history were recorded. Mann-Whitney U test and hierarchical binomial logistic regression analysis were applied. It was considered statistically significant at p < 0.05.ResultsThe case group’s DMFT, PI, GI, PD values were statistically significantly higher than the control group (p < 0.001). There was no relationship between DMFT, GI, PD, CAL and inflammatory blood markers (p > 0.05). In the regression analysis for possible risk factors that may be effective in P-PROM, oral and dental health parameters were the most effective.ConclusionsOral and dental health of women with P-PROM was found to be worse than that of the control group. Oral and dental health may be a potential risk factor that may contribute to adverse pregnancy outcomes associated with P-PROM.

A 3-D-printed wideband beamforming antenna with isoflux characteristics for Earth observation

This paper introduces a compact dielectrically loaded antenna with an isoflux beam. Fabricated from a lattice of alternating dielectric and air layers, this antenna is excited via a waveguide feed. By varying the thickness ratio of the dielectric layer to the overall unit cell, the effective permittivity of the antenna can be dynamically adjusted. Experimental results reveal that the antenna achieves an isoflux beam pattern in the E plane while projecting a pencil beam in the H plane. The maximum gain, about 12.2 dBi, manifests at a 30-degree offset from the boresight within the 22 GHz to 35 GHz frequency range. The height of the dielectric component measures roughly twice the wavelength at the central operational frequency. Design methodology has been validated through both fabrication and measurement, confirming performance of this proposed antenna, which boasts a simple structure and cost-effective production.

A design methodology for highly reliable operation for 2T0C dynamic random access memory application based on IGZO channel-all-around ferroelectric field-effect transistors

In this paper, the memory characteristics of In-Ga-Zn-O (IGZO)-channel ferroelectric FETs (FeFETs) with stackable vertical channel-all-around structure are investigated by technology computer-aided design (TCAD) simulation. The simulated drain current–gate voltage (I DS–V GS) curves of the IGZO FeFET show an on–off ratio of up to 107 and a memory window of 1.76 V, proving that ferroelectric hafnium oxide (FE-HfO2) is suitable for a 2T0C transistor. To solve the potential current-sharing problem of the 2T0C dynamic random access memory (DRAM) array, an advanced operation design methodology is proposed, which utilizes the bipolar polarization characteristics of FE-HfO2. This solution shows a remarkable current ratio between data “1” and data “0”, not only demonstrating the feasibility of the IGZO-based FeFET on 2T0C DRAM memory cells, but also providing an array design guideline for highly reliable 2T0C memory applications.

Using response surface methodology to optimize foam drying conditions related to drying rate and B-carotene concentration of orange-fleshed sweet potato powder

Response surface methodology and Box-Behnken design (3 factors and 3 levels) were performed to optimize the effects of different egg albumin contents (5-15%), xanthan gum (0.1-0.5%) and drying temperature (50-70oC). Drying rate and β-carotene content are indicators observed through 18 experimental runs and 6 repetitions at the center point. Finally, the physical properties such as color, water solubility index, water absorption index and rehydration ratio together with moisture content, water activity and microstructural of OFSP powder were analysed. The total polyphenol content (TPC), DPPH scavenging activity and β -carotene were analysed. Research results revealed that the optimal egg albumin concentration, xanthan gum concentration and drying temperature of 10.73%, 0.33% and 65.48oC, respectively as foam-mat drying parameters were recorded. From those optimal parameters, the optimal values of drying rate and β-carotene were determined to be 2.34 g water/g dry matter/min (maximize) and 51.82 µg/g (maximize), respectively. Foam-mat dried powder contained low moisture content and water activity, 4.15% and 0.343, respectively, along with water solubility index, water absorption index and rehydration ratio were respectively determined to be 45.87%, 2.36% and 3.97. The color of foam-mat dried OFSP powder was evaluated. According to the findings, the content of β-carotene (48.61±0.5 μg/g) and TPC (2.24±0.04 mgGAE/g) along with antioxidant activity (57.43±1.2%) of OFSP powder products were also determined. SEM analysis of OFSP powder particles at different magnifications showed that they have irregular surface morphology and flake-like structures, different from the structure of powder particles dried by convection drying method, the surface is quite smooth and the structure is intact.

Molecular ferroelectric with low-magnetic-field magnetoelectricity at room temperature

Magnetoelectric materials, which encompass coupled magnetic and electric polarizabilities within a single phase, hold great promises for magnetic controlled electronic components or electric-field controlled spintronics. However, the realization of ideal magnetoelectric materials remains tough due to the inborn competion between ferroelectricity and magnetism in both levels of symmetry and electronic structure. Herein, we introduce a methodology for constructing single phase paramagnetic ferroelectric molecule [TMCM][FeCl4], which shows low-magnetic-field magnetoelectricity at room temperature. By applying a low magnetic field (≤1 kOe), the halogen Cl‧‧‧Cl distance and the volume of [FeCl4]− anions could be manipulated. This structural change causes a characteristic magnetostriction hysteresis, resulting in a substantial deformation of ~10−4 along the a-axis under an in-plane magnetic field of 2 kOe. The magnetostrictive effect is further qualitatively simulated by density functional theory calculations. Furthermore, this mechanical deformation significantly dampens the ferroelectric polarization by directly influencing the overall dipole configuration. As a result, it induces a remarkable α31 component (~89 mV Oe−1 cm−1) of the magnetoelectric tensor. And the magnetoelectric coupling, characterized by the change of polarization, reaches ~12% under 40 kOe magnetic field. Our results exemplify a design methodology that enables the creation of room-temperature magnetoelectrics by leveraging the potent effects of magnetostriction.

Low-loss vanadium dioxide-enabled mmWave tunable reflective electromagnetic surface with complementary unit cells for wave manipulation

This study presents a novel implementation of vanadium dioxide (VO2) phase change material in an electromagnetic (EM) surface with beam steering capabilities. For the first time, we present the design, fabrication, and measurement of a globally actuated, VO2-based beamforming reflective EM surface. We propose a design featuring complementary unit cells that enable beam steering with a single excitation, marking a pioneering use of low-loss VO2 in creating a complementary EM surface for the mmWave band. The unit cells incorporating VO2 exhibit low-loss characteristics, with −0.92 and −1.9 dB in the hot state and −0.49 and −0.25 dB in the cold state, respectively. We incorporate both positive and negative phase variants alongside two temperature-independent phase unit cells. The complementary design enables us to utilize two beam operating states, effectively exploiting the otherwise unused cold state. We experimentally demonstrated beamforming at ±5° and ±10° from the broadside. In the case of ±10°, the measured gains at 35 GHz in the cold and hot states were 19.4 and 20.3 dB, respectively, which aligned well with the simulated gains of 20.9 and 21.5 dB. Manipulation of the electromagnetic wave direction with a single excitation has the potential for imaging, sensing, and communication applications. The complementary unit cell design methodology can be further adapted for mmWave beamforming, absorbing, and cloaking reconfigurable EM surfaces. Furthermore, the use of VO2 can be extended up to sub-THz frequencies due to the wideband, low-loss characteristics compared with conventional reconfigurable devices, such as PIN diodes or MEMS switches.