Probability-based Approach Research Articles

Echocaridographic assessment of pulmonary hypertension: improving the probability

Abstract Introduction Pulmonary hypertension (PH) is a cardio-pulmonary disorder characterised by raised pulmonary artery pressure (mPAP >20mmHg) leading to right ventricular failure, and death if left untreated. Transthoracic echocardiography (TTE) assessment of PH uses a probability-based approach, combining peak tricuspid regurgitant velocity with other supporting signs. We evaluated the latest ESC TTE PH guidelines in a real-world UK dataset and identified markers that may improve the sensitivity of the existing algorithm. Method Retrospective analysis of 447 patients referred for initial PH assessment. This was a select population of patients who underwent both TTE and right heart catheter (RHC) (mean time to RHC = 40±30 days). In addition to current TTE PH probability markers we analysed right ventricular free wall strain (RVFWS). Measurements were made by a single operator using Tomtec Arena 2020. Crosstabulation, ROC curve analysis and T-tests were used to compare variables between PH and no PH. Results Mean sample age was 64±15 yrs (61% female). 6.9% (n=4) of the no PH group had pulmonary mid-systolic notching, which may be due to pseudo-notching attributable to incomplete Doppler envelope. Sensitivity and specificity of current ESC TTE probability guidelines were 83%, and 65% respectively (95% C.I.). However, within the low probability group (i.e. those felt to be less likely to have PH) 62% (n=63) had confirmed PH at RHC (mPAP = 28±9). The addition of RVFWS as an additional marker to the existing supporting signs of PH (Table 1) resulted in an improvement of the sensitivity of the algorithm to 92% with a mild reduction in specificity (63%). The number of false negatives were reduced by 51%. Of these, the majority were in the low TTE probability group (n = 32). Conclusions Using current PH TTE probability algorithms classifies a significant proportion of those with PH as having a low TTE PH probability. The addition of RVFWS improves the sensitivity of the existing algorithm to 92% and reduces false negatives by 51%.

Management of neonates at risk of early onset sepsis: a probability-based approach and recent literature appraisal : Update of the Swiss national guideline of the Swiss Society of Neonatology and the Pediatric Infectious Disease Group Switzerland.

This guideline, developed through a critical review of the literature, facilitates a probability-based approach to the management of neonates at risk of early onset sepsis. • Neonatal exposure to antibiotics is disproportionally high compared with the incidence of early onset sepsis with implications for future health and antimicrobial resistance. • A probability-based approach may facilitate a more balanced management of neonatal sepsis and antibioticstewardship.

CSQUiD: an index and non-probability framework for constrained skyline query processing over uncertain data

Uncertainty of data, the degree to which data are inaccurate, imprecise, untrusted, and undetermined, is inherent in many contemporary database applications, and numerous research endeavours have been devoted to efficiently answer skyline queries over uncertain data. The literature discussed two different methods that could be used to handle the data uncertainty in which objects having continuous range values. The first method employs a probability-based approach, while the second assumes that the uncertain values are represented by their median values. Nevertheless, neither of these methods seem to be suitable for the modern high-dimensional uncertain databases due to the following reasons. The first method requires an intensive probability calculations while the second is impractical. Therefore, this work introduces an index, non-probability framework named Constrained Skyline Query processing on Uncertain Data (CSQUiD) aiming at reducing the computational time in processing constrained skyline queries over uncertain high-dimensional data. Given a collection of objects with uncertain data, the CSQUiD framework constructs the minimum bounding rectangles (MBRs) by employing the X-tree indexing structure. Instead of scanning the whole collection of objects, only objects within the dominant MBRs are analyzed in determining the final skylines. In addition, CSQUiD makes use of the Fuzzification approach where the exact value of each continuous range value of those dominant MBRs’ objects is identified. The proposed CSQUiD framework is validated using real and synthetic data sets through extensive experimentations. Based on the performance analysis conducted, by varying the sizes of the constrained query, the CSQUiD framework outperformed the most recent methods (CIS algorithm and SkyQUD-T framework) with an average improvement of 44.07% and 57.15% with regards to the number of pairwise comparisons, while the average improvement of CPU processing time over CIS and SkyQUD-T stood at 27.17% and 18.62%, respectively.

Empowered chaotic local search-based differential evolution algorithm with entropy-based hybrid objective function for brain tumor segmentation

In neuro-oncology, the precise segmentation of brain tumors from Magnetic Resonance Images is crucial for diagnosis, treatment planning, and monitoring disease progression. Accurate segmentation helps determine the tumor’s size, location, and growth potential, which is essential for formulating effective treatment strategies. In response to this challenge, we developed a novel approach using Chaotic Local Search-Enhanced Differential Evolution (CJADE). CJADE, particularly its variant CJADE-M, which employs chaotic maps selected through a probability-based approach, has proven effective in optimizing brain tumor segmentation. Our study shows that CJADE-M outperforms traditional metaheuristic algorithms on various evaluation metrics. We further enhanced CJADE-M with an entropy-based hybrid objective function, which improved accuracy and reduced computational time in tumor segmentation compared to conventional methods like Minimum Cross-Entropy and Kapur. This makes our method suitable for real-time medical imaging analysis. Our findings indicate that CJADE-M, equipped with the hybrid objective function, achieves superior segmentation performance for both benign lobulated and malignant irregular tumors across metrics such as PSNR, FSIM, QILV, and HPSI. By providing a more accurate and efficient tool, our approach can significantly enhance the outcomes of brain tumor diagnosis and treatment, improving patient care in neuro-oncology.

Multiple cracking and strain-hardening criteria of Engineered Cementitious Composites (ECC) with river sand

The inclusion of river sand in ECC alters the crack initiation and propagation behavior. As a result, the multiple cracking and pseudo strain-hardening of the river sand ECC (RS-ECC) are different from that of the typical micro-silica sand ECC. This study investigates the strain-hardening criteria for the RS-ECC by considering the matrix as a three-phase material containing pre-existing flaws along the sand/matrix interface with a given size distribution. Micromechanics is used to impart the new mechanisms in the analytic model for the steady-state crack analysis and the formulation of the strain-hardening criteria of ECC incorporating river sand. A probability-based approach is adopted to assess the strain-hardening potential of RS-ECC and validated with experimental results. Results show that the proposed model can predict the tensile properties of RS-ECC, which can be used to guide ingredients selection and components tailoring of RS-ECC to achieve required tensile strain-hardening performance.

Assessment of Soil Liquefaction Potential Using Genetic Programming Using a Probability-Based Approach

Assessment of Soil Liquefaction Potential Using Genetic Programming Using a Probability-Based Approach

Introducing surface roughness in adhesion for stochastic and Rock'n’Roll models to describe particle resuspension in turbulent flows

Resuspension of colloidal particles plays an important role in various environmental and industrial implications and is particularly influenced by the interactions at the particle-surface interface. Here we explore the effect of surface roughness on resuspension of colloidal particles by incorporating a phenomenological adhesion model that includes surface roughness into a stochastic resuspension model, and into the kinetic, probability-based approach Rock'n'Roll model to provide a more realistic description. Within this framework, we investigate the influence of stochasticity on the resuspended fraction and explore its dependence on particle size and surface roughness. Our findings show that introducing roughness into a stochastic resuspension scheme results in an increase of the resuspended fraction by an order of magnitude. Additionally, our results underscore the contribution of stochasticity in the resuspension process, in which the noise term enables the inclusion of important but less frequent events that contribute to the resuspension probabilities. In all, the introduction of roughness into both approaches result with a significant improvement in the reconstruction of experimental data, where the stochastic description shows better agreement.

The potential of facial nevi in personal identification

Forensic anthropologists dealing with personal identification (PI) of human remains have recently stressed the need to explore the potential of “secondary identifiers” for identifying victims who died in particular events for whom images often represent the main antemortem data available. Being the face the part most exposed in images, characteristics as pigmented skin lesions (PSLs), can be crucial if combined with other input. Since no data is available on frequencies and distribution of facial PSLs in the general population, this study aims at systematically collecting such data to verify their potential in PI and to open a debate on the aid that “secondary identifiers”, regardless of their specific nature, can give to the identification of the deceased in specific forensic contexts. A retrospective analysis on three-dimensional facial models of 1039 Italian subjects (from 4 to 84 years old) was conducted to examine the incidence of PSLs discriminated according to size and position in well-defined facial areas. From the collected data we developed a probabilistic approach providing the likelihood ratio (LR) for two settings: (1) the relative frequencies of nevi in the various facial areas, providing the deriving compound probability of owning a certain facial PSLs pattern; and (2) codes describing the facial nevi pattern of each individual of our population, thus testing their uniqueness and so their potential in PI. The calculated LRs mostly proved high identifying strength, particularly when provided by the compound probability-based approach. Data on incidence and position of facial nevi, their generated codes, and the probabilistic approach here presented, all constitute a starting point for advancing secondary identifiers. Nonetheless, although this preliminary study proved facial PSLs as valuable and potentially useful for identification, their significance and validity should be interpreted with caution as we are still at the first theoretical step clearly based on ideal conditions, and thus further investigations are due on the limitations of their use in practical identifying settings. Therefore, being this systematic study only a preliminary one in its nature, it is recommended not to use this kind of approach until further studies will test its validity in several practical conditions.

Improvement in Monte Carlo localization using information theory and statistical approaches

Monte Carlo localization methods deploy a particle filter to resolve a hidden Markov process based on recursive Bayesian estimation, which approximates the internal states of a dynamic system given observation data. When the observed data are corrupted by outliers, the particle filter’s performance may deteriorate, preventing the algorithm from accurately computing dynamic system states such as a robot’s position, which in turn reduces the accuracy of the localization and navigation. In this paper, the notion of information entropy is used to identify outliers. Then, a probability-based approach is used to remove the discovered outliers. In addition, a new mutation process is added to the localization algorithm to exploit the posterior probability density function in order to actively detect the high-likelihood region. The goal of incorporating the mutation operator into this method is to solve the problem of algorithm impoverishment which is due to insufficient representation of the complete probability density function. Simulation experiments are used to confirm the effectiveness of the proposed techniques. They also are employed to predict the remaining viability of a lithium-ion battery. Furthermore, in an experimental study, the modified Monte Carlo localization algorithm was applied to a mobile robot to demonstrate the local planner’s improved accuracy. The test results indicate that developed techniques are capable of effectively capturing the dynamic behavior of a system and accurately tracking its characteristics.

Parameters and Operation Modes of the Cutting and Chopping Apparatus

ntroduction. To improve the efficiency of harvesting crops, it is necessary to improve the existing tools of mowers and headers of combine harvesters that will ensure their versatility and multifunctionality. The increased power availability per the industry in the current economic and political conditions can be achieved by applying the principles of resource conservation and using alternative designs of reaper and headers. The existing cutting units of these agricultural machines do not provide simultaneous cutting, harvesting and chopping of corn stalks, sunflower stalks, reed steams and branches for the purpose of futher incorporation into the soil or collection of plant mass to use in liverstock. Therefore, substantiating the design and technological scheme and determinating the parameters and modes for the universal cutting and chopping apparatus is relevant. Aim of the Article. The aim of the work is to increase the efficiency of cutting and chopping plants by substantiating the structural and functional scheme of the unit and the ration parameters and operating modes of the cutting unit. Materials and Methods. The physics of the kinematic mode indicator is substantiated in terms of the probability-based approach. The research was carried out in the laboratory of the Department of Operation and Technical Service and in the training park of Kuban State Agrarian University. Results. There is substantiated the structural and functional scheme of the chopper unit with a cutterbar of cutting and chopping type. The physics of the kinematic mode index characterizing the intensity of interaction of a certain number of knives with plants on the root and stems distributed over the area with different density, is substantiated for the accepted conditions of the unit operation, in terms of probabilistic approach to the interaction of knives with stems in the form of plants on the root. Discussion and Conclusion. The obtained data are necessary for designing universal machines of a new type, providing not only cutting, but also collecting of cut stems, chopping and possible collecting of the chopped crop or spreading chopped crop on the field. Depending on the rotational speed of the auger tool, an indicator of the kinematic mode, the power varies from 4.99 kW to 11.02 kW, productivity from 0.5 kg/s to 1.22 kg/s, and energy consumption from 11.02 to 4.99 kW-s/kg.

Evaluation of Inter-Laboratory Comparison Results: Representative Examples

The primary purpose of inter-laboratory comparisons is to verify the CMC claims of the participating laboratories. The most commonly used evaluation criterion, the normalized error │Eni│, has flaws, particularly if the comparison uncertainty ucomp,i is large relative to the reference standards being compared. According to the recommendations of CIPM Working Group for Fluid Flow, the uncertainty ucomp,i should be considered by including the uncertainty of the transfer standard and the repeatability of the calibrations. A review of previous comparison reports shows the importance of this task for many other measurands beside the field of fluid flow. In this paper, we propose the use of comparison uncertainty ucomp,i as a better tool for assessing the power of the comparison. We applied the comparison evaluation criteria to recent comparison results to illustrate their benefits over the │Eni│≤ 1 criterion. A probability-based approach evaluates the comparison results and we recommend its usage in future comparisons.

Structural integrity of reinforced concrete slabs of some selected existing buildings based on field assessment

Quality assurance and reinforcement detailing may affect the primary function of a reinforced concrete slab to transfer the load upon it by bending. This paper is focused on a probability-based approach to investigate the structural integrity of the reinforced concrete slabs of two selected buildings at a university campus. The in situ strength of all accessible floor slabs was measured using the Schmidt rebound hammer and Ultrasonic pulse velocity tester. The loadings on the slabs were analysed using Orion Software on the structural layouts of the two buildings. The integrity of the slabs, measured by their reliability indices, considering the yielding of the steel and deflection criteria, were estimated using the first-order reliability procedure. The computed indices were related to a target reliability index of 3.8 for the ultimate limit state and 1.5 for the serviceability limit state, chosen for a 50-years reference period of Class RC2 structural members according to BS EN 1990:2002+A1:2005. Generally, the safety indices decrease as the applied loads/moments increase for all the slabs in the two buildings. Although the estimated safety indices reveal that the slabs are over-designed, some of the slab panels in one of the buildings will fail the deflection criterion when loaded to about 80% of their ultimate capacity. Based on this assessment, a disparity in quality assurance between the two buildings has been established.

Discussion of “Probability vs. Nonprobability Sampling: From the Birth of Survey Sampling to the Present Day” by Graham Kalton

In this excellent overview of the history of probability and nonprobability sampling from the end of the nineteenth century to the present day, Professor Graham Kalton outlines the essence of past endeavors that helped to define philosophical approaches and stimulate the development of survey sampling methodologies. From the beginning, there was an understanding that a sample should, in some ways, resemble the population under study. In Kiær’s ideas of “representative sampling” and Neyman’s invention of probability-based approach, the prime concern of survey sampling has been to properly plan for representing characteristics of the finite population. Poststratification and other calibration methods were developed for the same important goal of better representation.

Global and local path planning for mass point robots in two-dimensional environments

Robot path planning is a popular research topic due to its wide application. There are various approaches to apply to path planning, such as artificial potentials-based approach, probability-based approach, retraction-based approach, and heuristic approach. In this paper, the heuristic approach is focused on due to its convenience. In heuristic approach, considering the application, the author chooses fuzzy logic and neural network to apply to path planning. By conducting experiments both on PowerBot and the simulation environment, the methods proposed in the article are feasible. The environment data is collected by the sensors. Next, the fuzzy controller or neural network will process the data, and generate an appropriate path to get to the target without hitting any obstacles or walls.

Probability-Based Approach for Inverse Stochastic Structural Problems

The topic of this paper is related to the inverse stochastic mechanic problems, in which it is necessary to estimate the unknown mechanical and geometrical random quantities of the structures once the external loads and displacement responses are probabilistically known. In particular, in this work, a probability-based approach for inverse stochastic problems, working directly in terms of probability density functions (PDFs), is presented. This approach has been possible thanks to the application of the probability transformation method (PTM), which has been recently introduced for the solution of many stochastic analysis problems.

Lightning Protection With a Differentiated Configuration of Arresters in a Distribution Network

When concerning the installation and operation costs, it is always desirable to protect an overhead distribution network with a limited quantity of surge arresters (SAs). This paper presents a novel procedure for designing differentiated protection against lightning, by identifying appropriate positions for those SAs on the overhead line. Rather than the traditional flashover rate of a whole line, indices in terms of flashover numbers at individual poles and associated with possible stroke locations are introduced in this paper. Based on these flashover indices, a differentiated configuration of SAs can be identified using a selection strategy. After several rounds of selection, a differentiated SA protection scheme can be obtained, given by a pre-set quantity of SAs. In this procedure, a simplified probability-based approach is proposed to determine the flashover indices. By comparing the traditional Monte Carlo method, this approach can achieve a 10-fold increase in computational efficiency with reasonable accuracy. Two different selection strategies are introduced in this paper. Compared with the selection strategy using the flashover indices at individual poles, the selection strategy based on a group of poles is recommended because it yields a configuration with better lightning performance with the same quantity of SAs. This design procedure is applied to practical distribution networks with a shield wire and nearby structures. The influence of grounding impedance, a shield wire, and nearby structures is addressed. Finally, a generalized step-by-step procedure is provided to assist in a differentiated SA protection design.

A Forecast Cycle–Based Evaluation for Tropical Cyclone Rapid Intensification Forecasts by the Operational HWRF Model

Abstract An evaluation framework for tropical cyclone rapid intensification (RI) forecasts is introduced and applied to evaluate the performance of RI forecasts by the operational Hurricane Weather Research and Forecasting (HWRF) Model. The framework is based on the performance of each 5-day forecast cycle, while the conventional RI evaluation is based on the statistics of successful or false RI forecasts at individual lead times. The framework can be used to compare RI forecasts of different cycles, which helps model developers and forecasters to characterize RI forecasts under different scenarios. It also can provide the evaluation of statistical performance in the context of 5-day forecast cycles. The RI forecast of each cycle is assessed using a modified probability-based approach that takes the absolute errors in intensity changes into account. The overall performance of RI forecasts during a given period is assessed based on the fractions of the individual forecast cycles during which RI events are successfully or falsely predicted. The framework is applied to evaluate the performance of RI forecasts by the HWRF Model for the whole life cycle of a single hurricane, as well as for each of the hurricane seasons from 2009 to 2021. The metric based on the probabilities of detection and false alarm rate of RI is compared with that based on the absolute errors in the intensity and intensity change during RI events. Significance Statement An evaluation framework for tropical cyclone rapid intensification (RI) forecasts is introduced, focusing on the performance of RI forecasts in each 5-day forecast cycle. The cycle-based approach can help to characterize RI forecasts under different conditions such as certain synoptic scenarios, initial conditions, or vortex structures. It also can be used to assess the overall performance of RI forecasts in terms of the percentages of individual forecast cycles that successfully or falsely predict RI events.

Predicted health and environmental hazards of liquid crystal materials via quantitative structure-property relationship modeling

Liquid crystal materials (LCMs) are considered as emerging contaminants with high persistent and bioaccumulative potentials, but their toxicological effects are not well understood. To address this issue, a list of 1431 LCMs commercially available in the market was established through literature reviews and surveys of LCM suppliers. Toxicological properties of 221 target LCMs were derived from the Classification and Labeling Inventory by the European Chemicals Agency. More than 80 % of target LCMs likely pose adverse effects on human health or aquatic ecosystems. Two quantitative structure-property relationship (QSPR) models developed from the toxicological properties of LCMs achieved approximately 90 % accuracy in external data sets. The probability-based approach was more efficient in defining the applicability domain for the QSPR models than a range- or distance-based approach. The highest accuracy was achieved for chemicals within the probability-based applicability domain. The QSPR models were applied to predict health and environmental hazards of 1210 LCMs that had not been notified to the Classification and Labeling Inventory, and 301 and 94 LCMs were recognized as posing potential hazards to human health and the environment, respectively. The present study highlights the potential detrimental effects of LCMs and offers a specific in silico technique for screening hazardous LCMs.

Mathematical modeling and reliability analysis for pellet manufacturing unit of a polymer section

The study has been performed to know the availability of operating equipment in the industrial unit with mathematical modeling. The pellet manufacturing unit is a repairable system that can work satisfactorily after getting proper maintenance of a polymer section at naphtha cracker unit. It consists of various subsystems, namely steamer agitator, dryer, rotary feeders, feeders and screw feeder machine. The number of failures of a subsystem and its repair rate with respect to time are assumed to be constant. In current paper, system behaviour was analysed for knowing the actual availability in the unit with available maintenance data. The maintenance department’s history sheets were used to compile the data for all five subsystems. The probability-based approach of Markov process used for developing partial differential equations which are further solved by putting the sum of all the events equal to one. The steady state availability with known parameters were calculated to know the system availability. A critical analysis of subsystems has been carried out to enhance the performance of above said unit. It was observed that feeder subsystem was affecting the system availability more as compare to other subsystems. If failure rate increases, system availability decreases up to 7.0% and repair rate increases, availability increases up to 9.4%. That’s why maintenance priority should be given to this subsystem. The calculated results are communicated to the relevant authorities so that the right maintenance choices can be carried out on time.

Surface texture characterisation with reduced boundary effect for diamond-turned micro-structured surfaces

Micro-structured surfaces, fabricated by ultra-precision diamond turning (UPDT) with nanometric surface texture, have been widely used due to their wide range of functionalities. Their functional performance is closely related to their surface texture. To characterise the surface texture of the micro-structured surfaces, boundary effect would happen in the boundary area when surface filtering and yield a crucial impact upon their characterisation. However, the boundary effect has received relatively little attention for the surface texture characterisation. Hence, this study focuses on discussing the boundary effect in characterising the surface texture of micro-structured surfaces. Firstly, discrete wavelet transform (DWT) is used to extract the surface texture from the primary surface. Secondly, a probability-based approach is applied to remove the points with large amplitude at the boundary area of the micro-structures in order to reduce the boundary effect. Finally, the UPDT experiment is conducted for the fabrication of micro-structured surfaces and their surface texture is evaluated by the height parameters Sa, Sq, Sz, Ssk, and Sku of ISO 25178-2. The results show that the boundary effect can be reduced efficiently by the probability-based approach during surface filtering. Moreover, Sz, Ssk, and Sku could be more sensitive to the boundary effect than Sa and Sq due to their different statistical characteristics. Significantly, the study provides an effective method to reduce boundary effect in characterising the surface texture of micro-structured surfaces.