Fundamental Measure Research Articles

Impact of Building Orientation on Energy Performance of Residential Buildings in Various Cities Across Afghanistan

Building or solar orientation, a key architectural design parameter, significantly influences energy consumption in buildings. Optimizing building orientation to harness passive solar benefits is a fundamental and cost-effective measure in designing energy-efficient buildings. However, the optimal orientation varies based on geographical location, climatic conditions, and building type. Notably, Afghanistan’s building sector currently lacks tailored energy efficiency regulations. Therefore, this study investigates the impact of building orientation on the energy performance of residential buildings across nine cities in Afghanistan, each characterized by distinct climatic conditions and geographic locations, employing BEoptTM energy simulation software. The findings reveal diverse optimal orientations, dividing the country into three distinct climatic zones: subarctic (optimal orientation: south-southeast), continental (optimal orientation: south), and hot-arid (optimal orientation: north). The optimal orientations in these regions yield potential energy savings ranging from 25.6% to 48.9% compared to the least efficient orientations. These insights are critical for establishing location-specific building regulations in Afghanistan, promoting energy-efficient design, and addressing the country’s current trend of unsustainable development.

Flame kinetics at scramjet-engine-relevant conditions: Role of prompt dissociation of weakly-bound radicals

Combustion in high-speed ram-based propulsion engines occurs under distinct thermodynamic conditions of high reactant temperatures (greater than 1000 K) and relatively low pressures (<5 atm). There is a lack of fundamental flame measurements at such conditions that result in adiabatic flame temperatures (Tad) exceeding 2500 K. In this work, we have measured laminar flame speeds of oxygen-enriched CH4/oxidizer mixtures at sub-atmospheric conditions to probe kinetics at high Tad using the isobaric spherically expanding flame approach. Simulations with recent kinetic models revealed increasing differences between data and model predictions with increasing Tad, reaching up to 25 %. Kinetic analyses reveal that at the thermodynamic conditions in these O2-enriched flames, i.e., lower pressures and higher Tad, the effects of HCO prompt dissociation are accentuated. In addition to HCO, the prompt dissociations of CH2OH and C2H5 are also considered. The prompt dissociations of all three radicals were evaluated and their effects considered in flame speed simulations. Reaction path analysis for the present flames revealed that approximately half of the reaction flux for HCO formation undergoes prompt dissociation to H + CO. Furthermore, these analyses also revealed that the pathways and sensitive reactions are similar between oxygen-enriched fuel/oxidizer mixtures and preheated fuel/air mixtures, if both have similar Tad. Thus, flames of oxygen-enriched mixtures could be a surrogate to probe the flame chemistry of highly preheated mixtures at relatively low pressures that are often encountered in ram-based propulsion engine combustors.

Impact of mixing and configurational entropies on the entropy-driven potential of mean force

Using classical density functional theory (cDFT) with the fundamental measure functional (FMF) approximation, we examine how the entropic force and its integration, the potential of mean force (PMF), between two hard walls in a polydisperse hard-body solvent vary with monomer size polydispersity (whether the solvent consists of spherical monomers or chain molecules formed by freely linked monomers) or the number of monomers in the chain solvent. Molecular dynamics simulations validate the FMF's accuracy in predicting density distributions for five- and seven-component hard sphere fluids in slit geometries, though improvements are possible at high packing fractions. The PMF calculations reveal that increasing monomer size polydispersity or the number of monomers in a chain molecule reduce entropic attraction strength at contact and lower the main potential barrier height. This reduction is due to the system's limited capacity to further increase entropy when both mixing and conformational entropies are already high. For monomer or dimer solvent, the main potential barrier position shows either monotonic or non-monotonic dependence on monomer size polydispersity, depending on bulk packing fractions, while the PMF range shortens with increasing monomer size polydispersity or chain molecule monomer number. These findings could inform the design of tunable materials.

A Free-Standing Boron-Doped Diamond Grid Electrode for Fundamental Spectroelectrochemistry.

Spectroelectrochemistry (SEC) is a powerful technique that enables a variety of redox properties to be studied, including formal potential (Eo), thermodynamic values (ΔG, ΔH, ΔS), diffusion coefficient (D), electron transfer stoichiometry (n), and others. SEC requires an electrode which light can pass through while maintaining sufficient electrical conductivity. This has been traditionally composed of metal or metal oxide films atop transparent substrates like glass, quartz, or metallic mesh. Robust electrode materials like boron-doped diamond (BDD) could help expand the environments in which SEC can be performed, but most designs are limited to thin films (∼100-200 nm) on transparent substrates less resilient than free-standing BDD. This work presents a free-standing BDD grid electrode (G-BDD) for fundamental SEC measurements, using the well-characterized Fe(CN)63-/4- redox couple as proof-of-concept. With a combination of cyclic voltammetry (CV), thin-layer SEC, and chronoabsorptometry, several of the redox properties mentioned above were calculated and compared. For Eo', n, and D, similar results were obtained when comparing the CV [Eo' = +0.279 (±0.002) V vs Ag/AgCl; n = 0.97; D = 4.1 × 10-6 cm2·s-1] and SEC [Eo' = +0.278 (±0.001) V vs Ag/AgCl; n = 0.91; D = 5.2 × 10-6 cm2·s-1] techniques. Both values align with what has been previously reported. To calculate D from the SEC data, modification of the classical equation used in chronoabsorptometry was required to accommodate the G-BDD electrode geometry. Overall, this work expands on the applicability of SEC techniques and BDD as a versatile electrode material.

DOENÇA RENAL CRÔNICA CONCOMITANTE À ERLIQUIOSE: RELATO DE CASO

Kidney disease can range from acute kidney injury to chronic kidney disease, often caused by inflammation that impairs filtration. When kidney function is compromised, toxins accumulate, which can lead to kidney failure. In advanced cases, dialysis treatment becomes necessary. Other associated pathologies, such as ehrlichiosis, can make the condition irreversible. Ehrlichiosis triggers an inflammatory response affecting the kidneys, with the formation of immune complexes during infection. These complexes deposit in the renal capillaries, causing glomerulonephritis, an inflammation that impairs the function of the glomeruli, responsible for blood filtration. The purpose of this report is to present a case where kidney disease developed concomitantly with ehrlichiosis. In this case, an animal was referred to a veterinary hospital for dialysis treatment due to kidney disease. Laboratory tests were conducted, including a complete blood count, biochemical analysis, rapid ehrlichiosis test, and PCR, which confirmed the presence of active ehrlichiosis infection. Additionally, hemodialysis and dialysis sessions were performed, among other treatments. This case highlights the complexity and challenges of treating chronic kidney disease aggravated by ehrlichiosis, emphasizing the importance of advanced therapies and the need for ethical planning to balance available resources and the animal's quality of life. Raising awareness among pet owners about the risks, the importance of early diagnosis, correct treatment, and continuous monitoring are fundamental measures that can help in the early detection of kidney impairment and increase the chances of successful treatment.

A statistical mechanics investigation of unfolded protein response across organisms

Living systems rely on coordinated molecular interactions, especially those related to gene expression and protein activity. The Unfolded Protein Response is a crucial mechanism in eukaryotic cells, activated when unfolded proteins exceed a critical threshold. It maintains cell homeostasis by enhancing protein folding, initiating quality control, and activating degradation pathways when damage is irreversible. This response functions as a dynamic signaling network, with proteins as nodes and their interactions as edges. We analyze these protein-protein networks across different organisms to understand their intricate intra-cellular interactions and behaviors. In this work, analyzing twelve organisms, we assess how fundamental measures in network theory can individuate seed proteins and specific pathways across organisms. We employ network robustness to evaluate and compare the strength of the investigated protein-protein interaction networks, and the structural controllability of complex networks to find and compare the sets of driver nodes necessary to control the overall networks. We find that network measures are related to phylogenetics, and advanced network methods can identify main pathways of significance in the complete Unfolded Protein Response mechanism.

A BIOSSEGURANÇA NO ÂMBITO DA ODONTOLOGIA: REVISÃO DA LITERATURA

Kidney disease can range from acute kidney injury to chronic kidney disease, often caused by inflammation that impairs filtration. When kidney function is compromised, toxins accumulate, which can lead to kidney failure. In advanced cases, dialysis treatment becomes necessary. Other associated pathologies, such as ehrlichiosis, can make the condition irreversible. Ehrlichiosis triggers an inflammatory response affecting the kidneys, with the formation of immune complexes during infection. These complexes deposit in the renal capillaries, causing glomerulonephritis, an inflammation that impairs the function of the glomeruli, responsible for blood filtration. The purpose of this report is to present a case where kidney disease developed concomitantly with ehrlichiosis. In this case, an animal was referred to a veterinary hospital for dialysis treatment due to kidney disease. Laboratory tests were conducted, including a complete blood count, biochemical analysis, rapid ehrlichiosis test, and PCR, which confirmed the presence of active ehrlichiosis infection. Additionally, hemodialysis and dialysis sessions were performed, among other treatments. This case highlights the complexity and challenges of treating chronic kidney disease aggravated by ehrlichiosis, emphasizing the importance of advanced therapies and the need for ethical planning to balance available resources and the animal's quality of life. Raising awareness among pet owners about the risks, the importance of early diagnosis, correct treatment, and continuous monitoring are fundamental measures that can help in the early detection of kidney impairment and increase the chances of successful treatment.

OPTIMIZING AUTHENTICATION SECURITY IN INTELLIGENT SYSTEMS THROUGH VISUAL BIOMETRICS FOR ENHANCED EFFICIENCY

Context. The primary objective of this article is to explore aspects related to ensuring security and enhancing the efficiency of authentication processes in intelligent systems through the application of visual biometrics. The focus is on advancing and refining authentication systems by employing sophisticated biometric identification methods. Objective. A specialized intelligent system has been developed, utilizing a Siamese neural network to establish secure user authentication within the existing system. Beyond incorporating fundamental security measures such as hashing and secure storage of user credentials, the contemporary significance of implementing two-factor authentication is underscored. This approach significantly fortifies user data protection, thwarting most contemporary hacking methods and safeguarding against data breaches. The study acknowledges certain limitations in its approach, possibly affecting the generalizability of the findings. These limitations provide avenues for future research and exploration, contributing to the ongoing evolution of authentication methodologies in intelligent systems. Method. The two-factor authentication system integrates facial recognition technology, employing visual biometrics for heightened security compared to alternative two-factor authentication methods. Various implementations of the Siamese neural network, utilizing Contrastive loss function and Triplet loss function, were evaluated. Subsequently, a neural network employing the Triplet loss function was implemented and trained. Results. The article emphasizes the practical implications of the developed intelligent system, showcasing its effectiveness in minimizing the risk of unauthorized access to user accounts. The integration of contemporary authentication methodologies ensures a secure and robust user authentication process. Conclusions. The implementation of facial recognition technology in authentication processes has broader social implications. It contributes to a more secure digital environment by preventing unauthorized access, ultimately safeguarding user privacy and data. The study’s originality lies in its innovative approach to authentication, utilizing visual biometrics within a Siamese neural network framework. The developed intelligent system represents a valuable contribution to the field, offering an effective and contemporary solution to user authentication challenges.

A Theoretical Framework to Quantify Ecosystem Pressure-Volume Relationships.

'Water potential' is the biophysically relevant measure of water status in vegetation relating to stomatal, canopy and hydraulic conductance, as well as mortality thresholds; yet, this cannot be directly related to measured and modelled fluxes of water at plot- to landscape-scale without understanding its relationship with 'water content'. The capacity for detecting vegetation water content via microwave remote sensing further increases the need to understand the link between water content and ecosystem function. In this review, we explore how the fundamental measures of water status, water potential and water content are linked at ecosystem-scale drawing on the existing theory of pressure-volume (PV) relationships. We define and evaluate the concept and limitations of applying PV relationships to ecosystems where the quantity of water can vary on short timescales with respect to plant water status, and over longer timescales and over larger areas due to structural changes in vegetation. As a proof of concept, plot-scale aboveground vegetation PV curves were generated from equilibrium (e.g., predawn) water potentials and water content of the above ground biomass of nine plots, including tropical rainforest, savanna, temperate forest, and a long-term Amazonian rainforest drought experiment. Initial findings suggest that the stored water and ecosystem capacitance scale linearly with biomass across diverse systems, while the relative values of ecosystem hydraulic capacitance and physiologically accessible water storage do not vary systematically with biomass. The bottom-up scaling approach to ecosystem water relations identified the need to characterise the distribution of water potentials within a community and also revealed the relevance of community-level plant tissue fractions to ecosystem water relations. We believe that this theory will be instrumental in linking our detailed understanding of biophysical processes at tissue-scale to the scale at which land surface models operate and at which tower-based, airborne and satellite remote sensing can provide information.

Lattice Fundamental Measure Theory Beyond 0D Cavities: Dimers on Square Lattices

Using classical density functional theory, we study the behavior of dimers, i.e. hard rods of length L=2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L=2$$\\end{document}, on a two-dimensional cubic lattice. For deriving a free energy functional, we employ Levy’s prescription which is based on the minimization of a microscopic free energy with respect to the many-body probability under the constraint of a fixed density profile. Using that, we recover the "0D cavity" functional originally found by Lafuente and Cuesta and derive an extension by applying a more general "cluster density functional theory" method introduced by Lafuente and Cuesta as well. Moreover, we introduce a new free energy functional, which is based on approximated configurational probabilities. Both derived free energy functionals are exact on cavities that can hold at most two particles simultaneously. The first functional allows to improve the prediction of the free energy in bulk and both of them improve the prediction in highly confined systems, especially for high packing fractions, in comparison to the "0D cavity" functional.

Physical Patrol and Border Security Management at the Namanga One Stop Boarder Post, Kenya

Border administration encompasses all legal and administrative measures a sovereign state implements to secure, protect, and strengthen the sovereignty, security, safety, and integrity of its territory. Consequently, it is essential to any national migration strategy. The border administration policies emphasize the necessity for all participants in border management to be engaged to enhance the effectiveness of border operations. Security measures are normally enhanced along the border posts to improve on the national security of a given country by preventing entrance of terrorists, illegal goods and human trafficking. These security measures ensure safety at the border. The primary objective was to evaluate the effects of physical patrol on border security management at the Namanga one stop boarder post, Kenya. A descriptive survey research design was utilized. The population comprised of the employees at the Namanga OSBP, including police officers, customs officials, immigration officers, and National Intelligence Service employees, among others. The research used stratified random sampling. The data was collected via the use of questionnaires. Data analysis was done with the help of SPSS and then presented using tables, percentages, graphs and pie charts. This study found out that border security is complex and it requires various interventions, which entails a combination of technology and human security personnel for effective operations. In regard to objective one, the researcher finds that physical patrol emerges as a fundamental border security management measure, and is considered essential in enhancing security at the border point by minimizing insecurity incidents and eliminating potential of border security breaches. Based on the findings, this study concluded that various security measures, including physical patrols, integrated scanning, and electronic monitoring, are essential in the management of border security and in enhancing services. A major recommendation of the study is to promote greater multi-agency and multi-stakeholder collaboration as a means of detaining individuals attempting to enter a country illegally and effectively seizing any contraband goods. This necessitates more efficient border patrols and surveillance strategies.

Capturing autonomy, competence, and relatedness at work: further examining and validating an English language version of the work-related basic need satisfaction scale.

Self-Determination Theory (SDT) maintains that the satisfaction of the basic psychological needs for autonomy, competence, and relatedness is associated with optimal individual functioning, including in the workplace. A self-report instrument, the Work-related Basic Need Satisfaction scale (W-BNS), has previously been developed and validated in Dutch and Italian. We aimed to validate an English version of the W-BNS. We also evaluated a bifactor model to assess the extent to which the item responses could be explained by a single, underlying general latent trait. A Rasch calibration was also carried out to assess the extent to which the scores conformed to the assumptions of 'fundamental measurement' and could be converted to a common metric. We used data from 141 staff employed by a large UK-based mental health service provider. The postulated three-factor structure provided a good fit to the data. However, a bifactor model, introducing an underlying general factor, provided a superior fit. The items generally conformed to the Rasch measurement model. Evidence of convergent/divergent validity was observed via the correlations between the W-BNS scores and those for the Basic Psychological Needs Satisfaction and Frustration Scale (BPNFS). Regarding construct validity, both the separate needs and total W-BNS scores statistically significantly predicted an individual's reported intention to leave the current employer. Our findings foster research with the WBNS and have implications for how the W-BNS is optimally implemented in practice as a useful brief tool for assessing staff work-related need satisfaction.

Prediction OPEC oil price utilizing long short-term memory and multi-layer perceptron models

The present study undertakes a comprehensive assessment of two predictive models, namely Long Short-Term Memory (LSTM) and Multi-layer Perceptron (MLP), with a specific emphasis on their effectiveness in predicting oil prices, particularly those of the Petroleum Exporting Countries (OPEC). In this study, three fundamental statistical measures are utilized: The Symmetric Mean Absolute Percentage Error (SMAPE), the Mean Squared Error (MSE), and the Mean Absolute Percentage Error (MAPE). The results demonstrate that the LSTM model regularly surpasses the MLP model in the three benchmarks. In particular, the LSTM model demonstrates lower values for SMAPE, MSE, and MAPE, indicating higher prediction accuracy. The decreased error scores linked to the LSTM model highlight its improved capacity for precise oil price prediction in comparison to the MLP model. These results signify a notable progress in the use of machine learning techniques for predicting OPEC oil prices. Moreover, this study provides invaluable perspectives for OPEC management, policymakers, and organizations focused on oil price fluctuations, therefore contributing to the wider endeavour of enhancing the stability and economic sustainability of the oil pricing system in OPEC countries. The consequences of the study include the promotion of a pricing system that facilitates the achievement of economic and social development goals in these countries.

Construction and Optimization Strategies for Rural Residential Spatial Models Based on the Concept of Resource Metabolism: A Case Study of Rural Areas in the Shandong Plain

Rural communities can be conceptualized as spatial organisms interconnected by optimized resource utilization systems. Investigating the efficient utilization of rural resources and spatial construction methods grounded in resource metabolism is a pivotal step toward achieving the ecological transformation of rural spaces. This paper examined rural settlements in the Shandong Plain as a case study, exploring the relationships among three scales: village, neighborhoods, and courtyards. This analysis was based on elucidating the interaction mechanisms between “space and resource” and the integration of key resources and spatial elements. From the perspective of resource circulation and metabolism, this study aimed to elucidate the equilibrium of each resource element within three resource metabolism subsystems: the agricultural production system (core element), the ecological technology system (technological link), and the human life system (spatial carrier) in Shandong Plain’s villages, considering general climatic conditions. To achieve this, this research utilized the resource production volume, the utilization and transformation volume of resource metabolism technology facilities per unit area, and the average per capita resource consumption as fundamental measurement units. The concept of a rationing relationship is introduced to clarify resource allocation. Combining the aforementioned research on spatial resource metabolism in ecological villages in Shandong Province with the material flow analysis method, this study constructed a bottom–up spatial model of resource metabolism at three scales, courtyards, neighborhoods, and villages, under various resource metabolism scenarios. This study is anticipated to significantly contribute to the theoretical understanding of rural habitat environments, offering novel methods and perspectives for constructing ecological rural settlements.

Web-based vs. conventional: a comprehensive analysis of visual acuity assessment using the PocDoc tool in a tertiary eye care centre.

Visual acuity (VA) represents a fundamental measure of visual function. The significant prevalence of underdiagnosed ocular disorders underscores the importance of effective VA assessment. This study evaluates the efficacy of a web-based VA assessment tool ("PocDoc") versus conventional VA testing. Prospective observational study including 353 participants recruited from various eye clinics in a tertiary referral centre. Age, diagnosis, and VA related information (i.e. VA measurements from PocDoc and conventional VA test [Snellen chart], test type, etc) were collected. Spearman's rank correlation, Intraclass Correlation, and Bland-Altman plot compared outcomes of both tests. One-way ANOVA and paired-T test were used to compare means. Most patients were males (59.2%) with a mean age of 52.2 ± 20.6 years. PocDoc had moderate positive correlation to conventional testing (rho = 0.50, p < 0.001). PocDoc led to higher logMAR scores compared to conventional testing (mean logMAR 0.19 and 0.13 respectively, p < 0.01). Moreover, PocDoc demonstrated a sensitivity of 82.8% and specificity of 79% for detecting visual impairment. The discrepancy between PocDoc and conventional VA testing increased with higher logMAR values, indicating greater inconsistency between the tests for patients with poorer VA. Age, test type, and disease type contributed to this variability. The concordance between PocDoc and conventional testing for VA measurement across various ages and conditions makes it a suitable screening tool. Future technological inventions should consider age, test type, and disease type as critical factors related to the level of agreement and correlation between digital and conventional VA testing methods.

Purifying Selection Influences the Comparison of Heterozygosities between Populations.

Heterozygosity is a fundamental measure routinely used to compare between populations to infer the level of genetic variation and their relative effective population sizes. However, such comparison is highly influenced by the magnitude of selection pressure on the genomic regions used. Using over 2 million Single Nucleotide Variants (SNVs) from chimpanzee and mouse populations, this study shows that the heterozygosities estimated using neutrally evolving sites of large populations were two times higher than those of small populations. However, this difference was only ~1.6 times for the heterozygosities estimated using nonsynonymous sites. This suggests an excess in the nonsynonymous heterozygosities due to the segregation of deleterious variants in small populations. This excess in the nonsynonymous heterozygosities of the small populations was estimated to be 23-31%. Further analysis revealed that the magnitude of the excess is modulated by effective population size (Ne) and selection intensity (s). Using chimpanzee populations, this investigation found that the excess in nonsynonymous diversity in the small population was little (6%) when the difference between the Ne values of large and small populations was small (2.4 times). Conversely, this was high (23%) when the difference in Ne was large (5.9 times). Analysis using mouse populations showed that the excess in the nonsynonymous diversity of highly constrained genes of the small population was much higher (38%) than that observed for the genes under relaxed selective constraints (21%). Similar results were observed when the expression levels of genes were used as a proxy for selection intensity. These results emphasize the use of neutral regions, less constrained genes, or lowly expressed genes when comparing the heterozygosities between populations.

Density functional theory for responsive hard-sphere fluids

We investigate the equilibrium properties of responsive hard-sphere fluids, where the particle size is a coarse-grained property that fluctuates within an internal free-energy landscape, responding to changes in concentration or the application of external fields. For this purpose, we employ a generalised density functional theory for responsive colloids based on the fundamental measure theory for polydisperse hard-sphere mixtures. We find that increasing particle softness yields a substantial reduction in mean particle size, volume fraction and pressure. We also examine the density profiles and size segregation of responsive hard-sphere fluids subjected to three representative external potentials: a planar hard wall, gravitational and Archimedes buoyant fields. We observe that increasing stiffness or particle concentration enhances density oscillations, converging to the behaviour of a monodisperse fluid. In a gravitational field, size segregation occurs, with smaller particles accumulating at the bottom due to sedimentation. This effect is more pronounced when the Archimedes force is included, causing larger colloids to accumulate at the top, leading to density oscillations in this region that intensify with particle softness, an effect not observed in monodisperse systems. Finally, we demonstrate that responsiveness leads to distinct behaviour compared to conventional polydisperse non-responsive fluids, in which particle compression is not allowed.

The disruption index is biased by citation inflation

Abstract A recent analysis of scientific publication and patent citation networks by Park et al. (Nature, 2023) suggests that publications and patents are becoming less disruptive over time. Here we show that the reported decrease in disruptiveness is an artifact of systematic shifts in the structure of citation networks unrelated to innovation system capacity. Instead, the decline is attributable to ‘citation inflation’, an unavoidable characteristic of real citation networks that manifests as a systematic time-dependent bias and renders cross-temporal analysis challenging. One driver of citation inflation is the ever-increasing lengths of reference lists over time, which in turn increases the density of links in citation networks, and causes the disruption index to converge to 0. The impact of this systematic bias further stymies efforts to correlate disruption to other measures that are also time-dependent, such as team size and citation counts. In order to demonstrate this fundamental measurement problem, we present three complementary lines of critique (deductive, empirical and computational modeling), and also make available an ensemble of synthetic citation networks that can be used to test alternative citation-based indices for systematic bias. Peer Review https://www.webofscience.com/api/gateway/wos/peer-review/10.1162/qss_a_00333

Digitally accessible space: Discovery of the distinctive locational characteristics of restaurants with online reservation

The widespread adoption of ICT including mobile apps and their online services has significantly reshaped human activities in urban spaces. The complex interaction between ICT on urban space presents challenges in understanding their relationships. This study aims to discover the empirical evidence of the spatial variance of urban space linked to ICT. To pursue this objective, this study defines spaces that leverage ICT-based activities as Digitally Accessible Spaces (DAS), and choose restaurants that provide online reservation services through NAVER, which is the most dominant search engine in South Korea. Based on fundamental measurements in location theory, we stratified the entire area in Seoul into four groups in order of profitability. Using the location quotient (LQ), we quantified the locational characteristics of DAS compared to overall restaurants. Consequently, three measurements, which are density of marketplace, distance from public transit, and proper land use, indicate that the second-tier profitable areas commonly possess the largest portion of DAS. These characteristics provided empirical evidence supporting previous studies highlighting the liberation effect and altered travel behavior resulting from ICT-based activity through qualitative and theoretical approaches. We expect that this study can contribute to further research related to the interaction between digital space and physical space.

Data-Driven Modeling of DC–DC Power Converters

This article presents a data-driven methodology for modeling DC–DC power electronic converters. Using the proposed methodology, the dynamics of a converter can be captured, thereby eliminating the need for explicit theoretical modeling methods. This approach only requires the acquisition of fundamental measurements: currents through inductors and voltages across capacitors. The acquired data are used to construct a linear difference system, which is algebraically manipulated to form a state–space representation of the converter under analysis. Three DC–DC converter topologies were analyzed, and their resulting models were tested and compared with simulation data, yielding an average error deviation of approximately 2% for current signals and 4% for voltage signals, demonstrating precise tracking of the actual dynamics. The proposed data-driven methodology could simplify the implementation of adaptive control strategies in larger-scale solutions or in the interconnection of multiple converters.