Small Standard Deviation Research Articles

Investigation of propeller configuration effects on the flight stability of unmanned aerial vehicles

This study investigates the flight stability of unmanned aerial vehicles (UAVs) by comparing two-, three-, and six-blade propellers. The experiment uses a self-made drone with a 3D-printed polylactic acid (PLA) frame and an Arduino-based flight control system to create an efficient UAV prototype. The flight tests are conducted in a controlled environment, eliminating flight confounders such as wind and temperature, and the three types of propellers are of similar size. Stability was assessed by measuring deviations in the drone’s X and Y axes while hovering within ±30 degrees, and standard deviation (SD) was calculated to quantify variability. The tests revealed that propeller count significantly impacts stability and overall performance. The three-blade propeller provided the best stability, with the smallest SD in the X-axis at 10.85 and Y-axis at 11.85, and showed the least deviation over ±30 degrees during take-off and flight. While the 2-blade propeller has the least stability in flight, with a value of 15.08 in the X-axis and 16.3 in the Y-axis, showing a deviation exceeding ±30 degrees several times throughout the test, the 6-blade propeller demonstrates intermediate performance, with a value of 12.71 in the X-axis and 15.57 in the Y-axis, which is more stable than the 2-blade propeller but still less stable than the 3-blade propeller. The results of this study provide UAV design data by studying the factors in selecting propellers with different numbers of blades for drones, presenting information on the importance of propeller selection for drone flight performance and stability. The results of this study can be applied to various drone applications, such as aerial photography, agriculture, or industry. Finally, in the future, other factors are expected to affect the differences in the number of blades regarding energy efficiency and flight duration.

A Novel Approach to Microwave Heating Control System: Crow Search Algorithm-Based PID Controllers

Microwave heating technology has been implemented in various fields of life due to its superior advantages over conventional heaters. These advantages have sparked significant interest among researchers to further develop this technology, particularly from control system point of view. One crucial aspect of control system microwave heating development is finding an optimal controller tuning method to control the temperature properly. However, the research on control system tuning for this topic is still in its early stages. The main aim of this article is to utilize a novel approach with the potential to effectively enhance the performance of microwave heating control systems, namely Crow Search Algorithm (CSA). Autoregressive with Exogenous Variables (ARX) is used to simulate the proposed controller and assess its performance. The proposed controller is evaluated through simulations using MATLAB. Based on the fitness value tests, the optimized CSA solution tracks heating patterns well and predominantly produces a relatively small standard deviation of fitness values in the testing of the microwave heating control system. Overall, CSA effectively optimized controller parameters and achieved efficient control for the microwave heating system.

Self-perceived importance and confidence of adolescents transitioning to adult care

PurposeMotivational interviewing (MI) techniques are used by health care teams to engage adolescents and young adults (AYAs) in health care self-management and pediatric to adult health care transition (HCT) planning efforts. The aim of this study was to assess the initial level of motivation of AYAs prior to receipt of HCT anticipatory guidance and to determine associations with demographic and health coverage factors. MethodsThis retrospective study included 5112 AYAs, aged 12–26 years, from four health systems. All AYAs completed the Got Transition readiness assessment that includes MI questions on importance and confidence related to the move to an adult provider.Independent variables included demographic and health coverage factors: age, sex, race, ethnicity, language, and insurance type. The statistical approach included summary statistics, chi-square tests of independence and log-likelihood ratio tests, and generalized linear models and contrasts. ResultsThe study results demonstrate initial trends in importance and confidence scores for AYAs before they became part of a HCT planning process. Importance scores increased from 12-14 through 18–20 years of age, then decreased in the 21–26-year group. Confidence scores increased from the 12–14 through the 21–26-year group.Confidence scores were generally higher than importance scores and were accompanied by smaller standard deviations. Ethnicity and insurance type also demonstrated an association with MI scoring. DiscussionThis study provides baseline scores on two key MI importance and confidence questions that can facilitate clinician understanding of AYA engagement in discussing the changes needed to move to adult care and guides the clinician to start earlier than just before transfer that often occurs around age 21.

Orientation-Selective Memory Switching in Quasi-1D NbSe3 Neuromorphic Device for Omnibearing Motion Detection.

Intelligent neuromorphic hardware holds considerable promise in addressing the growing demand for massive real-time data processing in edge computing. Resistive switching materials with intrinsic anisotropy and a compact design of non-volatile memory devices with the capability of handling spatiotemporally reconstructed data is crucial to perform sophisticated tasks in complex application scenarios. In this study, an anisotropic resistive switching cell with a planar configuration based on lithiated NbSe3 nanosheets is demonstrated. Benefitting from the highly aligned diffusive channel associated with a quasi-1D van der Waals structure, the memristor patterned along NbSe3 atomic chains presents robust memory switching behavior with superior stability, particularly the low set/reset voltages (0.4V/-0.36V) and extremely small standard deviation (0.041V/0.051V), among the best compared to state-of-the-art devices. More importantly, unlike traditional resistive switching materials, anisotropic ion migration in NbSe3 crystals leads to a high orientation selectivity in the conductance update. Custom-designed neuromorphic hardware contributes to the implementation of omnibearing motion recognition for automatic pilot applications, yielding a high accuracy of 95.9% considering variations. This article presents a new strategy based on NbSe3 crystals to develop a neuromorphic computing system with intelligent application scenarios.

Variability and uncertainty of variance components in fixed-effects and mixed-effects ground-motion models

It has become common in the development of ground-motion models (GMMs), especially using mixed-effects regression with crossed random effects, to calculate standard deviations, referred to as variance components, from sample statistics of the residuals (i.e. random effects and within-group errors) rather than using the variance components reported by a mixed-effects regression program, calculated using the same algorithms used in the mixed-effects regression, or estimated using Bayesian inference. This practice leads to underestimating the standard deviations because it does not account for the uncertainty (i.e. standard errors) associated with fitting the random effects and within-group errors during the regression analysis. In this study, we used a series of ground-motion models for Fourier amplitude spectra developed using mixed-effects regression of an Next Generation Attenuation (NGA)-West2 database to show that residual-based standard deviations can be significantly smaller than regression-based standard deviations. These differences are exacerbated for those variance components with the fewest number of observations or when the residuals are partitioned (e.g. by earthquake magnitude). Using residual-based variance components not only results in smaller standard deviations but can lead to biased inferences when attempting to compare the efficacy of a model based solely on a comparison of the values of the variance components or their related mean square errors. It can also lead to biased fixed-effects coefficients if the variance components are derived from the residuals of a mixed-effects regression rather than estimated during a regression. We show that variance components can be decomposed into various random-effect grouping factors and partitioned into subsets of predictor variables, such as magnitude, from the total residuals of a non-Bayesian mixed-effects regression program using Bayesian inference. This process does not require the development of an entire GMM using Bayesian mixed-effects regression.

A novel back analysis framework for the probabilistic risk assessment of subaerial landslide-induced tsunami hazard

Numerical simulation is important for the risk assessment of subaerial landslide-induced tsunami (SLIT) hazards; however, their predictive performances are thus far limited as these works fail to consider the involved uncertainties. We propose a novel probabilistic risk assessment framework for quantifying several uncertainties, such as the model parameters and bias. We successfully couple the numerical simulation and Bayesian-based back analysis method. The wave height and run-up are captured by a three-dimensional granular-flow landslide and renormalization group turbulence model in FLOW3D; furthermore, the relevant parameter information is calibrated using a Markov chain Monte Carlo algorithm with the differential evolution adaptive metropolis. In this framework, which incorporates the prior information of model parameters, and field observations, as well as numerical model bias, calibrated parameters exhibit a probability distribution with a small standard deviation, facilitating improved risk prediction capabilities; In addition, the optimized adaptive Kriging-based surrogate model with multiple outputs is established to reduce the computation cost of the framework with acceptable accuracy. The framework's outputs, including a spatial probability that tsunamis inundate elements at risk, and a hazard zonation map, contribute to the evaluation of SLIT hazards and prioritize mitigation measures. Our work introduces a paradigm for the application of the framework, demonstrated through studies of two landslides in Wu Gorge. Without loss of generality, the framework offers a novel perspective for the quantitative assessment of SLIT hazards.

Eco-friendly synthesis and surface modification of ZnO nanoparticles using Pueraria montana root extract: enhanced photocatalytic performance with trisodium pyrophosphate

ABSTRACT The synthesis of zinc oxide (ZnO) nanoparticles using Pueraria montana (kudzu) plant extracts highlights advancements in green nanotechnology. This study explores the use of Pueraria montana roots, rich in phytochemicals such as phenols, terpenoids and flavonoids, which serve as natural reducing and stabilizing agents for nanoparticle synthesis. The eco-friendly production and surface modification of ZnO nanoparticles were achieved using these plant extracts, enhancing their photocatalytic performance with trisodium pyrophosphate (TSPP).Characterization techniques, including XRD, TEM, and FE-SEM, confirmed the nanoparticles’ crystalline structure, with a BET surface area of 14.01 m²/g and a type II adsorption isotherm. The synthesized nanoparticles exhibited exceptional dye degradation capabilities, achieving 99.9% removal of malachite green (MG) and 97.78% for aniline blue (AB). Kinetic analysis revealed a steady-state rate constant (k) of 2 × 10⁻⁴ min⁻¹ for MG where as the response rate constant(k) for the photocatalytic degradation of AB using modified ZnO nanostructures was 3.0 × 10−3 min−1 allowing near-total dye removal within 600 minutes for MG and 350 min for AB . Adsorption studies were well described by Langmuir and Freundlich isotherms, indicating maximum adsorption capacities of 59.7 mg/g for MG and 61.2 mg/g for AB. Surface modification with TSPP improved charge carrier separation and enhanced the generation of reactive oxygen species under UV exposure, further increasing dye degradation efficiency.Statistical analysis indicated high reproducibility, with close mean adsorption values of 99.125 for MG and 97.3125 for AB, supported by small standard deviations. The findings affirm the potential of using Pueraria montana in synthesizing efficient photocatalysts, providing a sustainable and cost-effective approach for water treatment applications. Overall, this research underscores the effectiveness of plant-based materials in advancing eco-friendly nanotechnology solutions.

Comparative Study of Seismic Hazard Analysis Using Classical PSHA and PSHA Method in Java Island, Indonesia

In general, seismic hazard analysis is conducted using a probabilistic approach (PSHA), whilst seismic risk analysis is computed using a stochastic approach. To figur out more differences between the two methods, a comparative study of those two approaches needs to be conducted. The study was conducted in Java Island which is the most populated island in Indonesia, and prone to earthquakes, particularly in the southern part due to the subduction of the Australian Plate and many active shallow faults along the island. To find out whether the hazards occurred in the risk analysis were closer to the results of Classical PSHA, it is necessary to examine the comparison of the two methods. The difference between the Event-Based and Classical methods is the use of a synthetic catalog that depends on the input value of SES (Stochastic Event Set). The research began with hazard computation with both methods, where the Event-Based PSHA method was given varying SES values. Determining the SES value in the Event-Based method is an important stage to conduct as a significant input parameter in a risk analysis, particularly the loss analysis. The comparison results conclude that the Event-Based PSHA with SES= 200,000 produced a wellconfirmed hazard map compared to the Classical PSHA result with the smallest standard deviation and variation, i.e. 0.0172 and 0.0003 respectively.

Evaluation of GOCE/GRACE and combined global geopotential models using GNSS/levelling data over Nigeria

AbstractGlobal Geopotential Models (GGMs) provide valuable information about Earth’s gravity field functionals, such as geoid heights and gravity anomalies. However, ground-based datasets are required to validate these GGMs at the regional and local scales. In this study, we validated the accuracy of GGMs by comparing them with ground-based Global Navigation Satellite System (GNSS)/levelling data for the first time in Nigeria. We employed two validation scenarios: with and without considering spectral consistency using the spectral enhancement method (SEM) to incorporate high and very high frequencies of the gravity field spectrum from the combined global gravity field model (XGM2019e_2159) and the residual terrain model (RTM) derived from the Shuttle Radar Topography Mission (SRTM) data, respectively. The results of this evaluation confirmed that the application of SEM improved the assessment of the GGM solutions in an unbiased manner. Integrating XGM2019e_2159 and SRTM data to constrain the high-frequency component of geoid heights in Gravity Field and Steady-State Ocean Circulation Explorer (GOCE)-based GGMs led to an improvement of approximately 10% in reducing the standard deviation (STD) relative to when SEM was not applied. GO_CONS_GCF_2_TIM_R6 at spherical harmonics (SH) of up to degree and order 260 demonstrated the lowest STD when compared to GO_CONS_GCF_2_DIR_R6 and GO_CONS_GCF_2_SPW_R5, with a reduction from 0.380 m without SEM application to 0.342 m with SEM implementation. In addition, four transformation models, namely, linear, four-parameter, five-parameter, and seven-parameter models, were evaluated. The objective is to mitigate the reference system offsets between the GNSS/levelling data and the GGMs and to identify the particular parametric model with the smallest STD across all GGMs. This effort reduced the GGMs misfits to GNSS/levelling to 0.30 m, representing a 15.3% decrease in STD. Notably, the XGM2019e_2159 model provides this improvement.

The impact of spinal versus general anesthesia on the variability of surgical times: a systematic review and meta-analysis.

With spinal anesthesia, when cases are taking longer than usual, there may be behavioural tendencies for surgical teams to work more quickly. We conducted a systematic review with meta-analysis to examine standard deviations of surgical times for single-dose spinal anesthetics versus general anesthesia. We compared ratios of mean surgical times as a secondary endpoint. We included randomized trials of humans where general or spinal anesthesia was used for one category of surgical procedure (e.g., hip arthroplasty) and the article reported the means and standard deviations of operative durations. We used statistical methods suitable for surgical times following log-normal distributions. We used generalized confidence intervals to calculate point estimates of ratios and standard errors for each study, followed by pooling among studies using DerSimonian and Laird random-effects meta-analysis with Knapp-Hartung adjustment. Among the 77 included studies, 96% were of high quality for our endpoint (i.e., had a low risk of bias), as no (0%) study focused on comparing variability of surgical times and none had surgical time as the primary endpoint. Spinal anesthesia was associated with 6.6% smaller standard deviations than general anesthesia (95% confidence interval, 15.8% smaller to 1.9% larger, P = 0.13). By meta-regression, there was no significant association of the ratios of standard deviations with study quality (P = 0.39), year of publication (P = 0.76), or categories of procedures (all five P ≥ 0.28). Spinal anesthesia was associated with 1.1% smaller means than general anesthesia (95% confidence interval, 3.7% smaller to 1.5% larger, P = 0.42). There were no significant associations between the ratios of means and study quality (P = 0.47), year of publication (P = 0.95), or categories of procedures (all five, P ≥ 0.63). The results of this systematic review and meta-analysis show with high confidence that the effect of choosing spinal anesthesia on variability in surgical time, if present, is sufficiently small to have no substantive direct economic effect. The same conclusion applies to mean surgical time. Therefore, although anesthetic choice has a clinical (biological) impact and affects anesthesia times, the direct effects on surgical times and workflow are minimal at most. Anesthetic choice does not influence operating theatre productivity via changes to surgical times. The impact of spinal anesthetic effects is limited to nonoperative times (e.g., reducing anesthesia-controlled times by using a block room before the patient enters the operating room). PROSPERO ( CRD42023461952 ); first submitted 8 September 2023.

Node Reporting and Data System Combined With Computed Tomography Radiomics Can Improve the Prediction of Nonenlarged Lymph Node Metastasis in Gastric Cancer.

To investigate the diagnostic performance of Node Reporting and Data System (Node-RADS) combined with computed tomography (CT) radiomics for assessing nonenlargement regional lymph nodes in gastric cancer (GC). Preoperative CT images were retrospectively collected from 376 pathologically confirmed of gastric adenocarcinoma from January 2019 to December 2023, with 605 lymph nodes included for analysis. They were divided into training (n = 362) and validation (n = 243) sets. Radiomics features were extracted from venous-phase, and the radiomics score was obtained. Clinical information, CT parameters, and Node-RADS classification were collected. A combined model was built using machine-learning approach and tested in validation set using receiver operating characteristic curve analysis. Further validation was conducted in different subgroups of lymph node short-axis diameter (SD) range. Node-RADS score, SD, maximum diameter of thickness of tumor, and radiomics were identified as the most predictive factors. The results demonstrated that the integrated model combining SD, maximum diameter of thickness of tumor, Node-RADS, and radiomics outperformed the model excluding radiomics, yielding an area under the receiver operating characteristic curve of 0.82 compared with 0.79, with a statistically significant difference (P < 0.001). Subgroup analysis based on different SDs of lymph nodes also revealed enhanced diagnostic accuracy when incorporating the radiomics score for the 4- to 7.9-mm subgroups, all P < 0.05. However, for the 8- to 9.9-mm subgroup, the combination of the radiomics did not significantly improve the prediction, with an area under the receiver operating characteristic curve of 0.85 versus 0.85, P = 0.877. The integration of radiomics scores with Node-RADS assessments significantly enhances the accuracy of lymph node metastasis evaluation for GC. This combined model is particularly effective for lymph nodes with smaller standard deviations, yielding a marked improvement in diagnostic precision. The findings of this study indicate that a composite model, which incorporates Node-RADS, radiomics features, and conventional parameters, may serve as an effective method for the assessment of nonenlarged lymph nodes in GC.

Measurement uncertainty of ISO CD 23351-2 - Preliminary results

The purpose of our study was to determine the measurement uncertainty of ISO CD 23351-2 draft standard. Two sub-studies were conducted. In study 1, an accuracy experiment was conducted where 7 participants tested in the same room (in situ) two different products (full enclosure and partial enclosure). In study 2, an experiment was conducted where a single participant tested two different products in several rooms varying in room volume and reverberation time. Study 1 yielded an in-situ reproducibility standard deviation of 0.80.9 dB. Study 2 yielded a between-site standard deviation of 0.7 dB. The small standard deviations suggest that the technical content should not be essentially changed in the next versions of the standard. The results could be considered in next version of the standard ISO DIS 23351-2.

Thermomagnetic recording of highly Bi-substituted iron garnet film using scanning laser for spatial light modulation

Spatial light modulations (SLM) utilizing the magneto-optical (MO) effect of magnetic materials are expected to offer fast switching and small pixel sizes as small as the wavelength of the light. However, the small MO effect is a major issue. In this paper, we report a thermomagnetic recording of highly bismuth-substituted garnet film, known for large Faraday effects. Y0.5Bi2.5Fe4GaO12 (Bi,Ga:YIG) film with a Faraday rotation of −4.66 degrees was used as an MO medium. A laser scanning thermomagnetic recording system using a Galvanometer mirror was developed and the size and quality of recorded magnetic domains were investigated. The smallest recorded magnetic domain diameter was 0.62 μm with a small standard deviation of 0.09 μm. Line patterns with a width of 1 μm can be recorded in this film. We found that Bi,Ga:YIG films have potential as a material for SLMs with fast switching, submicron pixel size, and large MO effect.

Synthesis of the modified SBA-15 mesoporous silica with TAN ligand to preconcentrate and determine trace amounts of Ni (II) ions in water and wastewater samples.

The synthesis of modified mesoporous silica (SBA-15), a powerful and highly effective adsorbent, was provided for the preconcentration, extraction, separation, and determination of trace amounts of Ni (II) ions. In this method, SBA-15 modified with 1-(2-thiazolylazo)-2-naphthol (TAN) was used as a suitable absorbent. The absorption of Ni (II) ions was studied using the FAAS technique. Transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), energy-dispersive spectroscopy (EDS), Fourier-transform infrared (FT-IR) spectroscopy, and CHNS elemental analysis techniques were used to assess the characteristics of SBA-15 and TAN/SBA-15. Effective parameters (pH, amount of nanocomposite, extraction time, and type of recovery solvent) for extracting Ni (II) ions via TAN/SBA-15 were investigated. The merit figures of the method were obtained with appropriate results, such as detection limit, accuracy, enrichment factor, and preconcentration factor. The calibration curve was linear within the range of 5.0-50ngmL-1 with a detection limit of 1.8ngmL-1. High preconcentration, small relative standard deviations, and enrichment factors (approximately 100) were represented by the statistical analysis. The proposed method for measuring Ni (II) ions was used at trace levels in real samples, such as seawater, river water, well water, and wastewater from a textile factory, an electrical power station, an MDF factory, and a food industrial company, with satisfactory results.

Role of gaze behaviors, body movements, and bicycle movements during cycling on a straight and narrow path

Cycling requires the integration of gaze behaviors, body movements, and bicycle movements. However, whether these movements contribute to skilled cycling performance, such as cycling on straight and narrow paths are uncertain. The present study aimed to differentiate optokinetic nystagmus (OKN) from vestibulo-ocular reflex (VOR) that characterize the relationship between eye and head movements during cycling on straight and narrow path, and to identify gaze behaviors, body movements, and bicycle movements that contribute to cycling performance. Nineteen participants with no prior competitive experience cycled three times on a 12-cm wide path. The participants were asked to avoid deviating from the path as much as possible. The measured variables were gaze behavior in a sagittal plane, body movement, and bicycle movement. As a result, OKN was observed among 16 of the 19 participants. The cross-correlation between the eye and head did not show negative value, indicating the absence of VOR. These results suggest that the participants moved their eyes while keeping their heads stable during cycling on a straight and narrow path. In the results of the multiple regression analysis, the variables with small standard deviations (SD) of the steering angle and upward eye position were related to a lower deviation from the path. These results suggest that a small SD of the steering angle and directed gaze in the forward direction may contribute to skilled cycling.

Do the different expressions of an artist offer the same financial performance over time? The case of Fernando Botero

PropósitoLos índices de rentabilidad del arte generalmente se estiman basándose únicamente en unos pocos medios de expresión artística (principalmente pinturas y dibujos). Otras formas de expresión artística (por ejemplo, esculturas e instalaciones) generalmente se ignoran, en parte porque son tridimensionales y, por tanto, más difíciles de medir. Analizamos los determinantes del precio, así como el retorno y el riesgo de tres expresiones artísticas (pinturas, dibujos y esculturas) ejecutadas por Fernando Botero, el artista latinoamericano vivo más caro, para analizar en qué medida sus atributos de riesgo y retorno difieren a lo largo del tiempo, en un período de 20 años.Diseño/metodología/enfoqueAnalizamos todas las pinturas, dibujos y esculturas ejecutadas por Botero y vendidas en Sotheby’s y Christie’s entre 2000 y 2020 (un total de 707 obras de arte). Los datos y las imágenes de cada obra se obtuvieron de las páginas web de estas dos casas de subastas. Se realizó una regresión hedonante para explicar el precio de cada obra de arte y se utilizaron variables explicativas estándar en la literatura. Los índices de precios de arte para pinturas, dibujos y esculturas se construyeron utilizando variables ficticias anuales estimadas en las regresiones. Realizamos un análisis similar para otro artista, Carlos Cruz-Diez, como análisis de robustez de nuestros resultados.HallazgosEl desempeño de las esculturas de Botero a través del tiempo difiere marcadamente del de sus pinturas y dibujos. Nuestros resultados sugieren que es posible que los retornos estimados en la literatura sufran un sesgo, ya que generalmente han ignorado el desempeño de esculturas y otras expresiones artísticas. Las pinturas de Botero proporcionaron un retorno comparable al de sus esculturas (3.36% y 3.20%, respectivamente), pero fueron dos veces superiores a los de sus dibujos (1.68%). Por otro lado, mientras que las pinturas y los dibujos tuvieron desviaciones estándar anuales similares (26% y 25.22%, respectivamente), las esculturas tuvieron una desviación estándar mucho menor (16.96%).Limitaciones/implicacionesUna limitación del método de regresión hedónica radica en la necesidad de contar con una muestra significativa y diversa para identificar el verdadero efecto de cada variable sobre el precio de un bien. Otra limitación consiste en que solo pudimos utilizar precios de arte de subastas, ya que esta es la única fuente completa de datos sobre precios de arte que está disponible públicamente. Estas dos limitaciones son compartidas por todos los estudios que utilizan el modelo de precios hedónico.Implicaciones prácticasNuestros resultados tienen aplicaciones prácticas para coleccionistas e inversores de arte, así como también para artistas, galerías y, en general, para todo el ecosistema del mercado del arte. Los atributos de riesgo y retorno de las diversas expresiones de un artista pueden ser diferentes, por lo que tiene sentido analizar cada una de ellas individualmente, así como sus correlaciones con las otras expresiones artísticas y con las inversiones tradicionales y otras alternativas.Implicaciones socialesEl mercado del arte forma parte de lo que se conoce como “economía naranja” (también conocida como Economía Creativa). Según el Banco Mundial, el valor económico del sector creativo no es bien conocido ni apreciado, a pesar de que las actividades culturales, creativas y artísticas son vitales para nuestra sensación de bienestar.Originalidad/valorHasta donde hemos podido comprobar, este es el primer artículo que compara el desempeño financiero de pinturas, dibujos y esculturas para el caso de un artista específico. Elegimos a Botero por tres razones. En primer lugar, es el artista vivo latinoamericano que ha alcanzado los mayores niveles de ventas internacionales. En segundo lugar, Botero ha trabajado extensamente en diversas expresiones artísticas (óleos, dibujos sobre distintos materiales y esculturas) a lo largo de su vida, característica que resulta fundamental para poder realizar nuestro estudio. En tercer lugar, existe un largo historial de ventas en subasta de cada una de las expresiones artísticas de Botero.

Long-term stability of squeezed light in a fiber-based system using automated alignment.

Providing a cloud service for optical quantum computing requires stabilizing the optical system for extended periods. It is advantageous to construct a fiber-based system, which does not require spatial alignment. However, fiber-based systems are instead subject to fiber-specific instabilities. For instance, there are phase drifts due to ambient temperature changes and external disturbances and polarization fluctuations due to the finite polarization extinction ratio of fiber components. Here, we report the success of measuring squeezed light with a fiber system for 24h. To do this, we introduce stabilization mechanics to suppress fluctuations in the fiber system and an integrated controller to automatically align the entire system. The squeezed light at a wavelength of 1545.3nm is measured every 2min, where automated alignments are inserted every 30min. The squeezing levels with an average of -4.42 dB are recorded with an extremely small standard deviation of 0.08 dB over 24h. With the technologies developed here, we can build complicated optical setups with the fiber-based system and operate them automatically for extended periods, which is promising for cloud service of quantum computation.

Quantitative Approach to Quality Review of Prenatal Ultrasound Examinations: Fetal Biometry.

Background/Objectives: To evaluate the quality of an ultrasound practice, both large-scale and focused audits are recommended by professional organizations, but such audits can be time-consuming, inefficient, and expensive. Our objective was to develop a time-efficient, quantitative, objective, large-scale method to evaluate fetal biometry measurements for an entire practice, combined with a process for focused image review for personnel whose measurements are outliers. Methods: Ultrasound exam data for a full year are exported from commercial ultrasound reporting software to a statistical package. Fetal biometry measurements are converted to z-scores to standardize across gestational ages. For a large-scale audit, sonographer mean z-scores are compared using analysis of variance (ANOVA) with Scheffe multiple comparisons test. A focused image review is performed on a random sample of exams for sonographers whose mean z-scores differ significantly from the practice mean. A similar large-scale audit is performed, comparing physician mean z-scores. Results: Using fetal abdominal circumference measurements as an example, significant differences between sonographer mean z-scores are readily identified by the ANOVA and Scheffe test. A method is described for the blinded image audit of sonographers with outlier mean z-scores. Examples are also given for the identification and interpretation of several types of systematic errors that are unlikely to be detectable by image review, including z-scores with large or small standard deviations and physicians with outlier mean z-scores. Conclusions: The large-scale quantitative analysis provides an overview of the biometry measurements of all the sonographers and physicians in a practice, so that image audits can be focused on those whose measurements are outliers. The analysis takes little time to perform after initial development and avoids the time, complexity, and expense of auditing providers whose measurements fall within the expected range. We encourage commercial software developers to include tools in their ultrasound reporting software to facilitate such quantitative reviews.

PENGENDALI PINTAR DALAM PENGONTROLAN LAMPU DAN KIPAS MENGGUNAKAN BLUETOOTH

The evolution of mobile technology has revolutionized it from a mere communication tool to a versatile platform capable of handling images, videos, documents, and controlling other devices such as TVs. The Android OS gives developers the flexibility to create applications that meet the diverse needs of users. This shift has made smartphones indispensable, supporting tasks from browsing to entertainment and productivity. The popularity of Android ensures seamless integration with existing hardware for efficient application performance. This research aims to design a smart home device control system, focusing on lights and fans via Android on an Arduino Nano microcontroller. Android's affordability and development through third-party applications make it ideal for smart home systems. Integrating the Arduino Nano and the EMS Blue Shield Bluetooth module improves convenience and energy efficiency. Its limitations include control of basic functions (lights, fan speed) and Android smartphones with Bluetooth. This study aims to design a practical control system and understand the device operation and Android communication. The test results of data transmission response time (latency) show that the average response time of the system for five days is 122.3 ms, with small variations and standard deviations between 2.81 ms and 3.92 ms. The range of response time ranged from 118 ms to 130 ms.

A Gate-Level Power Estimation Approach with a Comprehensive Definition of Thresholds for Classification and Filtering of Inertial Glitch Pulses

Estimation of power consumption in digital circuits is performed at gate-level simulation. Its accuracy depends on the models of gate delays that capture the effects of spurious signal transitions, called “glitches”. Electronic Design Automation (EDA) software considers inertial gate delays and represses a glitch in the cell’s output if its width is below a threshold. Selecting threshold values for the inertial glitch classification and filtering is crucial for precise power estimations. In this direction, we explore the effectiveness of automatically adjusting such thresholds on a cell-specific basis according to the local cell’s information. We used a commercial industry-standard gate-level power estimation tool and a 32 nm CMOS standard cell library. Via power measurements in circuit simulations, we created customized lookup tables for each library cell employed in the benchmark circuits. We compared the proposed approach’s performance with other methods for glitch threshold definition. Our method demonstrated good power estimation accuracy while presenting the lowest mean absolute error among all the cells of the circuits under test and the smallest standard deviation. The latter suggests that the proposed method achieves better cell-specific accuracy, which is expected to allow for more precise circuit-level power estimations in complex circuits with a large number of combinational cells.