Logical Test Research Articles

Improving the Security of United States Elections with Robust Optimization

The preservation of democracy hinges on the reality and perception that votes in elections are counted properly. In the paper “Improving the Security of United States Elections with Robust Optimization,” Crimmins, Halderman, and Sturt provide a low-cost approach to reducing the security risks of voting machines that are used to scan ballots and count votes. Their approach consists of applying robust optimization to a century-old testing procedure called logic and accuracy testing (LAT), which is performed by election officials on each voting machine before each election. The authors show that their robust optimization approach is guaranteed to detect any misconfiguration of voting machines that would cause votes to be swapped across candidates. Applying their approach to Michigan’s November 2022 election, the authors show that their approach to LAT would have only required a 1.2% increase in cost to election officials compared with current practice. Their approach, which is forthcoming in the Societal Impact section, has been successfully piloted in real-world elections by the Michigan Bureau of Elections since Summer 2023 as a cost-efficient way to enhance election security and public trust in election outcomes.

Impact of Neuropsychological Assessment on Subjective Memory Complaints in Patients With Mild Cognitive Impairment.

Patients with Alzheimer's disease (AD), namely at an initial stage like amnestic cognitive impairment (aMCI), typically present with memory complaints. They also have difficulties regarding self-knowledge about their cognitive deficits. In clinical practice, a formal neuropsychological assessment is often done. The present study aimed to understand whether patients with aMCI retain the ability to monitor the success or failure in their performance during the neuropsychological assessment and adjust the report of memory complaints accordingly, as compared to healthy controls. Participants were patients with aMCI and healthy controls who were questioned about their own memory abilities using the Subjective Memory Complaints (SMC) scale, applied before and after the neuropsychological assessment protocol. A repeated measures General Linear Model was performed to analyze changes in SMC (within-subjects effects) after the neuropsychological assessment, in patients with aMCI and healthy controls (between-subjects effects). Eighty volunteers, 40 patients with aMCI and 40 healthy controls, participated in the study. Patients with aMCI showed lower MMSE scores, more depressive symptoms, and deficits in memory and learning, language and executive domains. Patients with aMCI had higher SMC scores [9.4(3.6)] than healthy controls [4.4(2.3)] before the neuropsychological assessment. A statistically significant interaction was found between the SMC and the diagnostic group, meaning that healthy controls decreased SMC [3.4(1.9)] after the neuropsychological assessment, whereas patients with aMCI kept high levels of SMC [9.6(3.9)]. In patients with aMCI, an inverse correlation between logical memory and the change in SMC was found, so that patients with lower scores in the logical memory test tended to increase their memory complaints after the assessment. Both patients with aMCI and healthy controls can monitor and update the impression about their memory abilities following a formal neuropsychological assessment. Patients with aMCI maintain a high SMC level, which is inversely associated with their memory performance. In practical terms, SMC should be measured consistently at a particular moment in time, preferably preceding the objective neuropsychological assessment.

Post-stroke fatigue severity is associated with executive dysfunction in chronic stroke

ABSTRACT Following stroke, fatigue is highly prevalent and managing fatigue is consistently rated a key unmet need by stroke survivors and professionals. Domain-specific cognitive impairments have been associated with greater fatigue severity in earlier stages of stroke recovery, but it is unclear whether these associations hold in chronic (>2 years) stroke. The present cross-sectional observational study evaluates the relationship between domain-specific cognitive functioning and the severity of self-reported fatigue among chronic stroke survivors. Participants (N = 105; mean age = 72.92, 41.90% female; mean years post-stroke = 4.57) were assessed in domains of attention (Hearts Cancellation test), language (Boston Naming Test), episodic memory (Logical Memory Test), working memory (Digit Span Backwards task), and executive functioning (set-shifting: Trail Making Test, Part B), as part of the OX-CHRONIC study, a longitudinal stroke cohort. Fatigue was assessed using the Fatigue Severity Scale. In a multiple linear regression analysis inclusive of above cognitive domains, only poorer executive functioning was associated with increased fatigue severity. This provides insight into the cognitive impairment profile of post-stroke fatigue long-term after stroke, with executive functioning deficits as the key hallmark.

Voice biomarkers in middle and later adulthood as predictors of cognitive changes.

Prosody voice measures, especially jitter and shimmer, have been associated with cognitive impairment and hold potential as early indicators of risk for cognitive decline. Prior research suggests that voice measures assessed concurrently with longitudinal cognitive outcomes are associated with 10-year cognitive declines in middle-age and older adults from Midlife in the U.S. (MIDUS) study. Using a subsample from the same study, we expanded previous research to examine voice measures that were (1) collected 8 years before cognitive outcomes, (2) derived from narrative speech in logical memory tests instead of word list recall tests, and (3) independent of the cognitive outcomes. Multilevel analyses controlled for covariates of age, sex, education, neurological conditions, depressive symptoms, and chronic conditions. The results indicated that higher jitter and lower shimmer predicted greater 10-year declines in episodic memory and working memory. These findings extend previous research by highlighting prosody voice measures assessed 8 years earlier as predictors of subsequent cognitive declines over a decade.

Effect of tDCS combined with virtual reality for post-stroke cognitive impairment: a randomized controlled trial study protocol

BackgroundPost-stroke cognitive impairment (PSCI) not only increases patient mortality and disability, but also adversely affects motor function and the ability to perform routine daily activities. Current therapeutic approaches for, PSCI lack specificity, primarily relying on and medication and traditional cognitive therapy supplemented by a limited array of tools. Both transcranial direct current stimulation (tDCS) and virtual reality (VR) training have demonstrated efficacy in improving cognitive performance among PSCI patients. Previous findings across various conditions suggest that implementing a therapeutic protocol combining tDCS and VR (tDCS - VR) may yield superior in isolation. Despite this, to our knowledge, no clinical investigation combining tDCS and VR for PSCI rehabilitation has been conducted. Thus, the purpose of this study is to explore the effects of tDCS - VR on PSCI rehabilitation.MethodsThis 4-week, single-center randomized clinical trial protocol will recruit 200 patients who were randomly assigned to one of four groups: Group A (tDCS + VR), Group B (tDCS + sham VR), Group C (sham tDCS + VR), Group D (sham tDCS + sham VR). All four groups will receive conventional cognitive rehabilitation training. The primary outcome measurement utilizes the Mini-Mental State Examination (MMSE). Secondary outcome measures include the Montreal Cognitive Assessment, Frontal Assessment Battery, Clock Drawing Test, Digital Span Test, Logic Memory Test, and Modified Barthel Index. Additionally, S-YYZ-01 apparatus for diagnosis and treating language disorders assesses subjects’ speech function. Pre- and post-four-week intervention assessments are conducted for all outcome measures. Functional near-infrared spectroscopy (fNIRS) is employed to observe changes in oxygenated hemoglobin (HbO), deoxy-hemoglobin (HbR), and total hemoglobin (HbT) in the cerebral cortex.DiscussionOur hypothesis posits that the tDCS - VR therapy, in opposed to individual tDCS or VR interventions, could enhance cognitive function, speech ability and daily living skills in PSCI patients while concurrently augmenting frontal cortical activity. This randomized study aims to provide a robust theoretical foundation supported by scientific evidence for the practical implementation of the tDCS - VR combination as a secure and efficient PSCI rehabilitation approach.Trial registrationChictr.org.cn Identifier: ChiCTR2300070580. Registered on 17th April 2023.

Maternal factors associated with stunting among children under two years in South Nias, Indonesia: a cross-sectional study

The Indonesian Nutritional Status Survey 2022 reported that the prevalence of stunted children in South Nias, a district in North Sumatera, was 27.2%, higher than the regional and national prevalence of stunting. Stunting can be caused by many factors including maternal nutritional status, exclusive breastfeeding, and inadequate food intake. This research aims is to analyze the relationship between maternal factors and cases of stunting in children under two years at Somambawa Community Health Center, South Nias Regency. It was a quantitative study with a cross sectional design. Using a total sampling technique, 72 mothers with children under two years were included in the study. Exact fisher statistical and logical regression tests were carried out in bivariate and multivariate analyses. This study found that there was a significant relationship between antenatal care visits (p-value=0.000) and exclusive breastfeeding (p-value=0.000) with stunting in children under two years old. Exclusive breastfeeding was the most dominant predictor of stunting in the study, namely 84 times (p-value=0.000; OR 84.00). Meanwhile, complementary feeding and knowledge did not show a significant relationship with stunting. Therefore, health education to provide information and knowledge about stunting, especially about exclusive breastfeeding and complementary food for babies is suggested.

Chanting and Enchantment: A Philosophical Communicology of Idolic Submission and Emotional Intoxication Part I: Foundation

In this first of two articles on chanting and enchantment we introduce the problem of mass synchronisation via collective communicative action that works to eliminate or lessen independent and critical assessment. Chanting forges a singular ‘collective’ identity with little to no structure that would allow for logical tests such as falsifiability. We argue that this problem can be a fundamental threat to democratic polity, and we offer the Neo-Kantian theory of dimensional accrual and dissociation as an explanation. In Part 2, we will continue with examples and a discussion of the confluence of philosophical examination and social scientific explanations.

Story recall performance and AT classification via positron emission tomography: A comparison of logical memory and Craft Story 21

BackgroundEarly detection of Alzheimer's disease (AD) is one of the critical components of the global response to the growing dementia crisis. Analysis of serial position performance in story recall tests has yielded sensitive metrics for the prediction of AD at low cost. In this study, we examined whether serial position markers in two story recall tests (the logical memory test, LMT, and the Craft Story 21 test, CST) were sensitive to cross-sectional biomarker-based assessment of in vivo neuropathology. MethodsParticipants were selected from the Wisconsin Registry of Alzheimer's Prevention (n = 288; WRAP) and the Alzheimer's Disease Research Center (n = 156; ADRC), both from the University of Wisconsin–Madison. Average age at PET was 68.9 (6.7) and 67.0 (8.0), respectively. Data included tau and PiB PET, and LMT for WRAP participants and CST for ADRC participants. Two sets of Bayesian analyses (logistic regressions and ANCOVAs) were conducted within each cohort, separately. ResultsResults indicated that the A+T+ classification was best predicted, cross-sectionally, by the recency ratio (Rr), indexing how much of the end of the story was forgotten between initial learning and delayed assessment. Rr outperformed traditional scores and discriminated between A+T+ and A+T−/A-T-, in both cohorts. ConclusionsOverall, this study confirms that serial position analysis of LMT and CST data, and particularly Rr as an index of recency loss, is a valuable tool for the identification of in vivo tau pathology in individuals free of dementia. Diagnostic considerations are discussed.

Pengaruh Durasi Penggunaan Gadget dan Durasi Belajar Mahasiswa Informatika terhadap Kemampuan Logika dan Hasil Belajar Matematika

This research aims to investigate the effect of the duration of gadget use and the duration of study on logical abilities and its impact on the mathematics learning outcomes of students in the Informatics Engineering Study Program, STMIK Palangkaraya. The sample was taken using a purposive sampling technique, namely, 65 active students who had taken the Calculus 1 course. The data used were gadget usage duration data, study duration data, logical ability test results, and learning outcomes for the Calculus 1 course. Data was collected using observation techniques, questionnaires, tests, and documentation, and then path analysis was carried out to determine the direct and indirect influence of exogenous variables on endogenous variables with the help of Python. The results of the study indicate that logical ability has a positive but relatively weak influence on mathematics learning outcomes (path coefficient value: 0.1525), while the length of learning directly has a positive and fairly strong influence (1.1160). Learning results in mathematics and reasoning skills are not impacted by the amount of time spent using a device. The duration of gadget use has no effect on logical abilities or mathematical learning outcomes.

Validity and Reliability of Questionnaire for Assessing Pharmaceutical Services at MMC Hospital

Pharmaceutical service implementation by pharmacists at community health centers is governed by Minister of Health Regulation No. 74 of 2016. This regulation necessitates the evaluation of pharmaceutical services to ensure service quality provided by pharmacists. This study aims to develop a questionnaire for assessing the quality of pharmaceutical services at MMC Hospital (Metropolitan Medical Centre). Conducted in two phases—questionnaire design and validation—this quantitative research formulated 23 statements across 5 service dimensions based on Minister of Health Regulation No. 74 of 2016. Logical validity testing identified 22 statements as valid per expert assessment. Content validity was assessed using Content Validity Ratio (CVR) and Content Validity Index (CVI), resulting in the elimination of statements with CVR < 0.99 and CVI < 70%. Construct validity and reliability were evaluated with 100 eligible respondents, confirming 22 statements with valid construct validity (r > 0.148). Reliability testing yielded Cronbach's Alpha values exceeding 0.6, indicating reliability of all valid statements. Consequently, 22 questionnaire statements were validated for assessing pharmaceutical service quality at MMC Hospital.

Computing grounded theory: a quantitative method to develop theories

The inductive logic of grounded theory and the principle of avoiding theoretical preconceptions are significantly different from the deductive logic and hypothesis testing of traditional quantitative research. Based on the limitations of theory production in quantitative research, this paper proposes a Computing Grounded Theory (CGT) approach that directly quantitatively assists theories. With the help of machine learning and attribution algorithms, CGT identifies variables that have not been the focus of previous studies based on the predictive power of the independent variables to propose new theoretical hypotheses, following the principle that causality is a sufficient and unnecessary condition for predictability. This paper systematically discusses CGT’s basic idea, logical premise, and methodological foundation while providing an empirical example. This method bridges the gap in the theoretical production of quantitative research and is of great value in theory, discipline, knowledge systems and social governance.

Public hospital reform, family health consumption and health inequality: evidence from China Family Panel Studies.

In 2017, China launched a comprehensive reform of public hospitals and eliminated drug markups, aiming to solve the problem of expensive medical treatment and allow poor and low-income people to enjoy basic health opportunities. This study attempts to evaluate the policy impact of public hospital reform on the health inequality of Chinese residents and analyze its micro-level mechanism from the perspective of household consumption structure. Studying the inherent causal connection between public hospital reform and health inequality is of paramount significance for strengthening China's healthcare policies, system design, raising the average health level of Chinese residents, and achieving the goal of ensuring a healthy life for individuals of all age groups. Based on the five waves of data from the China Family Panel Studies (CFPS) conducted in 2012-2020, We incorporates macro-level statistical indicators such as the time of public hospital reforms, health insurance surplus, and aging, generating 121,447 unbalanced panel data covering 27 provinces in China for five periods. This data was used to explore the impact of public hospital reform on health inequality. Logical and empirical tests were conducted to determine whether the reform, by altering family medical care and healthy leisure consumption expenditures, affects the micro-pathways of health inequality improvement. We constructed a two-way fixed model based on the re-centralized influence function (RIF_CI_OLS) and a chained mediation effects model to verify the hypotheses mentioned above. Public hospital reform can effectively improve the health inequality situation among Chinese residents. The reform significantly reduces household medical expenses, increases healthy leisure consumption, promotes the upgrading of family health consumption structure, and lowers the health inequality index. In terms of indirect effects, the contribution of the increase in healthy leisure consumption is relatively greater. Public hospital reform significantly alleviates health inequality in China, with household health consumption serving as an effective intermediary pathway in the aforementioned impact. In the dual context of global digitization and exacerbated population aging, enhancing higher education levels and vigorously developing the health industry may be two key factors contributing to this effect.

Association between oral health and cognitive impairment in older adults: Insights from a Six-year prospective cohort study

ObjectiveThis study aims to investigate the relationships between four baseline oral conditions (periodontal status, dental caries, tooth wear, and dentition) and repeated global cognition or domain-specific cognition (memory, executive function, attention, and verbal fluency) in non-demented older adults over time. MethodsThis prospective cohort study (2011–2019) enrolled 516 non-demented community-dwelling older adults (age ≥ 65) to explore the association between oral health and cognitive function. Global and domain-specific cognition were assessed biennially (four repeats) using a battery of neuropsychological tests. The baseline oral health conditions were examined, including periodontal status, dental caries, tooth wear, and dentition. The association of these oral conditions with cognition was evaluated by generalized linear mixed models. Stratified analyses were performed by important covariates. ResultsOver time, dental caries was associated with poor memory in two different logical memory tests (β^= -0.06 and β^= -0.04). Incomplete dentition with less than 28 teeth was associated with poor performance in attention (β^= -0.05) and verbal fluency (β^= -0.03). These associations became more evident in those with an elevated inflammatory marker (IL-6, β^= -0.11 to -0.08). In contrast, tooth wear was associated with better memory in two different logical memory tests (β^= 0.33 and β^= 0.36) and better executive function (β^= 0.06) over time, and this association became more evident in those with the lowest inflammatory marker (IL-6, β^= 0.10). ConclusionsDental caries and incomplete dentition were associated with poor memory, attention, and verbal fluency performance. Conversely, tooth wear was associated with better memory performance and executive function. Clinical SignificanceFor early prevention of dementia, an evaluation of multiple dental and periodontal status in older adults helps predict the risk of dementia in the preclinical phase. Maintaining intact tooth structure without caries progression and eventually tooth loss may help prevent the worsening of memory, attention, and verbal fluency over time.

Development and status quo of digestive endoscopy in China: An analysis based on the national census in 2013 and 2020.

Technique and practice of digestive endoscopy are undergoing speedy development all over the world. This study aimed to evaluate its status quo and development in China. All hospitals performing digestive endoscopy in mainland China participated in the national census in 2013 and 2020. Retrospective data of hospitals, endoscopists, volumes, and qualities were collected via an online structured questionnaire, and its accuracy and rationality were verified by logical tests and manual reviews. Data from other countries were used to compare with that of China. From 2012 to 2019, the number of hospitals performing digestive endoscopy increased from 6,128 to 7,470 (1.22-fold), in which primary healthcare played a minor role. The median hospitals per 100,000 inhabitants per provincial region increased from 0.49 (IQR, 0.39-0.57) to 0.55 (IQR, 0.49-0.63). The endoscopists increased from 26,203 to 39,638 (1.51-fold), but their average workload even expanded. Overall volume increased from 28.8 million to 44.5 million (1.55-fold), and most types of endoscopic procedures recorded a high growth rate. Contrastingly, the specific utilization rates were low and paled in comparison with some developed countries. Nationwide, regional utilization rates showed a significant correlation with GDP per capita (P <0.001). Overall qualities of digestive endoscopy were excellent, but certain results of quality indicators posed a huge challenge, such as the detection rates of adenoma and early cancers. Impressive progress has been made in digestive endoscopy with rapidly expanding economy in China. However, primary healthcare, utilization rates, and income-related inequality of regional services were needed to be improved to promote public health better.

Transcranial direct current stimulation-efficacy in mild cognitive impairment: A meta-analysis.

Mild cognitive impairment (MCI) is a transition state in which individuals have cognitive abilities that are in between those of normal aging and dementia. Although not everyone with MCI develops dementia, the risk of progression to dementia is higher in people with MCI. Interventions at this stage can prevent or delay the onset of dementia. In recent years, studies on non-invasive brain stimulation techniques, namely transcranial direct current stimulation (tDCS), have gained momentum for cognitive enhancement in MCI. Since there are very few studies that also report varied results, it becomes important to analyze the effect of tDCS in MCI. The aim of this study was to systematically review the available evidence about using tDCS for MCI and to assess its efficacy using meta-analysis. Eight single- or double-blinded randomized controlled trials were included in the study. Montreal cognitive assessment (MoCA) and mini-mental state examination (MMSE) for global cognition; and digit span test forward and backward, trail-making test (TMT) A and B; and logical memory test (LMT) assessing specific cognitive domains were considered. A random-effects model was used wherein the standardized mean difference (SMD) and its 95% confidence intervals were reported. The effect of the active tDCS (MoCA [SMD 0.37, 95% CI -0.22-0.95], MMSE [SMD 0.26, 95% CI 0.25-0.77], TMT-A [SMD -0.01, 95% CI -0.42-0.40], and LMT [SMD 0.80, 95% CI -0.24-1.83]) when compared with the sham tDCS was statistically insignificant. The current meta-analysis identified insignificant improvement in cognitive performance with active tDCS treatment as compared to sham tDCS among people with MCI.

The Positive Association between Melatonin-Containing Food Consumption and Older Adult Life Satisfaction, Psychoemotional State, and Cognitive Function.

The purpose of this study was to test the hypothesis that melatonin-containing food (FMT) consumption is associated with a better sleep schedule and cognitive and psychoemotional state in older adults. A cross-sectional study of 557 (79% females) older adults living in the community with a mean age of 68.9 ± 7.7, ranging from 50 to 90 years, was conducted. The study, conducted in May and September 2023 using a face-to-face interview, collected personal data and assessed FMT intake during the day (FMTday) and for dinner (FMTdinner), life satisfaction, positive and negative affect, depression severity, cognitive functions, and sleep characteristics. Multiple regression and logistic regression analysis, adjusted for co-factors, were used to assess the association between the studied indicators. Multiple regression analysis showed that older adults with higher FMT consumption are more satisfied with life (FMTdinner: β = 0.107; ∆R2 = 0.011; p = 0.020), have a lower level of depression (FMTday: β = -0.124; ∆R2 = 0.015; p = 0.003), and higher scores in positive affect (FMTday: β = 0.169; ∆R2 = 0.016; p = 0.007; FMTdinner: β = 0.136; ∆R2 = 0.019; p = 0.003). Logistic regression analysis showed that older adults with higher FMT consumption are less likely to have depression (FMTday: OR, 0.614; 95% CI, 0.436-0.864; p = 0.005; FMTdinner: OR, 0.671; 95% CI, 0.476-0.945; p = 0.023), and they perform better on logical thinking tests (FMTday: OR, 2.066; 95% CI, 1.131-2.204; p = 0.013; FMTdinner: OR, 1.887; 95% CI, 1.183-2.138; p = 0.033). A greater life satisfaction as well as a decrease in the cognitive impairment and psychoemotional state of older adults is associated with a higher consumption of melatonin-containing foods.

A branch, bound and remember algorithm for maximizing the production rate in the simple assembly line balancing problem

The simple assembly line balancing problem is a classical optimization problem. It aims at efficiently assigning elementary operations to the workstations of a paced assembly line to optimize some efficiency measure. In this paper, we deal with the type-2 version of the problem in which the efficiency measure is the maximization of throughput with a given number of workstations. This problem has been scarcely studied compared to its type-1 counterpart, in which the throughput is fixed and the objective is to minimize the number of workstations. This has led to the development of indirect methods using type-1 exact solution methods to tackle the type-2 case.In this paper, we provide lower bounds, logical tests, and dominance rules for the type-2 problem and adapt the state-of-the-art method for the type-1 problem to develop a direct approach for solving the type-2 problem with a direct approach. Computational results show the effectiveness of the direct method, which can outperform recent type-1-based indirect approaches. The proposed method is able to close all instances from the classical instance set and solves to optimality over 90% of the large (100 tasks) and 76.5% of the very large (1000 tasks) instances derived from the current reference set for its type-1 counterpart. The average gaps between the upper and lower bounds on the optimal cycle time are also tight and are less than 0.13% (0.4%) for large (very large) instances. Finally, our results show that direct and indirect methods are comparable in terms of solution quality, but the direct method outperforms its indirect counterpart in terms of running time and optimality gaps. Moreover, we identify that instances averaging two to three tasks per workstation and featuring large variability between task times pose significant challenges to solve to optimality.

Game-based Assessment: The Development of Logical Reasoning Test

This study aims to test the validity of a game-based logical reasoning test tool called the Library Game. This tool consists of eight stimuli, each representing interrelated scenarios that follow a specific pattern to address problems. Data analysis results show that the eight stimuli in the Library Game are unidimensionally valid in measuring logical reasoning constructs (n=284, chi-square=30.742, df=21, p-value=0.078, RMSEA=0.040, CFI=0.996, TLI=0.995). Furthermore, the researchers calibrated the items using Item Response Theory (IRT) 1 PL (parameter logistic). The results show that all items fit the established model. The level of item difficulty ranges from easy to moderate (-0.962 to 0.122). Therefore, this test can provide optimal information when administered to a population with an average level of logical reasoning. In conclusion, instead of conventional methods (question-answer format), valid assessment tools can be developed through innovative games.

Inter-compartment concentration monitoring of key species in a vanadium redox flow cell operating with and without polarization: Experiments and construction of a predictive model

The usually encountered phenomenon of vanadium crossover in Vanadium Redox Flow Batteries (VRFB), leading to energy capacity losses, is specifically studied without (diffusion measurements) and with the application of an electric current (battery operating conditions). The experimental set-up is an electrochemical filter-press reactor integrating a NafionTM 424 membrane and two storage tanks. The electrolytes composition on both sides was determined using potentiometric titration (VO2+ and H+) and UV–Vis analysis (V2+, V3+ and VO2+). First, experiment is conducted without polarization and a model based on mass balance equation incorporating diffusion flux and electrolyte volumes change is derived to predict electrolytes composition on both sides. The effective diffusion coefficient of VO2+ in the membrane is obtained by fitting the model with experimental data. The experiment is then carried out under galvanostatic polarization (10 mA/cm2) and a model embedding, simultaneously, electrolyte volumes variation, diffusion and migration across the membrane and the electrochemical and self-discharge reactions, is proposed to predict electrolytes composition. The partitioning of the applied current between all possible electrochemical reactions is addressed using a specific algorithm based on logical tests on limiting currents. The resulting system of coupled ordinary differential equations is solved numerically using standard python functions. The results indicate a satisfactory agreement between predicted and experimental data and highlight the requirement of considering all phenomena for an accurate prediction of electrolytes composition in VRFB. The interest of applying the developed model to simulate and predict composition evolution in VRFB (State of Charge (SoC) and acidity) is discussed.

Application of the Fuzzy Mamdani Method for Predicting Rainfall in the City of Yogyakarta

Weather and climate play an important role in everyday life, influencing various aspects of society and the environment. The city of Yogyakarta as a cultural center cannot be separated from the impacts of climate change, including rainfall patterns which can have significant effectiveness on daily activities, agriculture and infrastructure. This research uses a fuzzy logic methodology approach with the Mamdani method to predict rainfall. Fuzzy logic has proven to be effective in cold situations and is able to overcome the challenges of missing or incomplete data. The data used in this research was obtained from Bappeda DIY. The implementation for predicting rainfall levels uses Matlab by utilizing the provided Fuzzy Logic Matlab Toolbox. Based on research conducted using a fuzzy logic test to calculate all research accuracy data, an average error value in RMSE was obtained of 39.88%. These results indicate that there is significant error in these predictions, indicating that the fuzzy logic control model is not completely accurate. Therefore, it is necessary to review the data used in this prediction to ensure its accuracy.