Basis Of Tests Research Articles

Osteoarticular TB specimen yield rates. Large joint analysis at a single centre.

Tuberculosis (TB) remains endemic in South Africa. The spine, hip, and knee joints are common extra-pulmonary TB sites. Sound history taking, clinical examination, and basic laboratory and pathological tests remain key important steps in osteoarticular TB diagnosis. In our resources-stricken context cost is everything, if we can make a diagnosis cheaply that would go a long way. The diagnostic yield of standard laboratory tests compared to a real-time polymerase chain reaction (PCR) for osteoarticular TB diagnosis in a single orthopaedic unit has not been analysed. We conducted a retrospective record review of extra-spinal osteoarticular TB infection at our hospital from 01 June 2016 to 31 December 2021. Patient demographics, clinical history, and laboratory test results were analysed. A total of 34 cases were identified, with 32 of the cases being articular and two osseous involvement. The knee was the most common joint affected followed hip joint. Acid Fast Bacilli were detected in 32% of cases with microscopy, while TB culture was positive in 29% of samples. Histopathological examination and real-time PCR diagnosed TB in 66% and 63% of the cases, respectively. Our findings suggest that in the right context of a suggestive history and examination, histological analysis is as good as PCR for diagnosing osteoarticular TB.

Fine quantitative characterization of high-H2S gas reservoirs under the influence of liquid sulfur deposition and adsorption

In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs, three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-pressure core displacement experiments. Fine quantitative characterization of the cores in three steady states (original, after sulfur injection, and after gas flooding) was carried out using the nuclear magnetic resonance (NMR) transverse relaxation time spectrum and imaging, X-ray computer tomography (CT) of full-diameter cores, basic physical property testing, and field emission scanning electron microscopy imaging. The loss of pore volume caused by sulfur deposition and adsorption mainly comes from the medium and large pores with sizes bigger than 1 000 μm. Liquid sulfur has a stronger adsorption and deposition ability in smaller pore spaces, and causes greater damage to reservoirs with poor original pore structures. The pore structure of the three types of carbonate reservoirs shows multiple fractal characteristics. The worse the pore structure, the greater the change of internal pore distribution caused by liquid sulfur deposition and adsorption, and the stronger the heterogeneity. Liquid sulfur deposition and adsorption change the pore size distribution, pore connectivity, and heterogeneity of the rock, which further changes the physical properties of the reservoir. After sulfur injection and gas flooding, the permeability of Type I reservoirs with good physical properties decreased by 16%, and that of Types II and III reservoirs with poor physical properties decreased by 90% or more, suggesting an extremely high damage. This indicates that the worse the initial physical properties, the greater the damage of liquid sulfur deposition and adsorption. Liquid sulfur is adsorbed and deposited in different types of pore space in the forms of flocculence, cobweb, or retinitis, causing different changes in the pore structure and physical property of the reservoir.

VALIDITY AND RELIABILITY OF BASIC MANIPULATIVE MOVEMENT SKILLS TESTS FOR EARLY CHILDREN 6-8 YEARS

Basic motor skills assessment tests are widely used, including tests of manipulative basic movement skills. The basic manipulative movement skill test is used to measure the basic manipulative movement skills of early childhood. The purpose of this study was to find out whether it is suitable and effective for measuring basic manipulative movement skills in early childhood 6-8 years. The sample population used in this study were 30 different early childhood children aged 6-8 years in Pecallan Village, Natar District, South Lampung. Construct validity and reliability were calculated using Pearson's correlation with the results obtained that the study included 4 indicators, namely throwing, catching, hitting, and kicking, the results obtained were r count > r table (28; 5%) = 0.361. So it can be stated that all the indicator items used are valid. And based on the reliability test with Cronbach alpha, a value of 0.806 > 0.7 is obtained, so that it represents that these items are reliable for measuring the sample. In conclusion, thus that the manipulative basic movement skills test can be used to measure basic movement skills in early childhood 6-8 years.

Impact of Bilingualism on Speech Sound Disorder/ Articulatory and Phonological Disorders

Impact of Bilingualism on Speech Sound Disorder/ Articulatory and Phonological Disorders

Thermal Oxidative Aging Effect on Chemo-Rheological and Morphological Evolution of Crumb Rubber Modified Asphalt Binders with Wax-Based Warm Mix Additives

Wax-based warm mix additives can decrease the viscosity and improve the workability of crumb rubber (CR)-modified asphalt, but the mechanism of influence on the aging performance of CR-modified asphalt is not clear. To investigate the thermal aging behavior and mechanism of wax-based warm mix CR-modified asphalt, polyethylene wax (PEW) and polyamide wax (PAW) were mixed to prepare warm mix CR-modified asphalt. The effect of thermal aging on the rheological and mechanical properties was characterized by a basic property test, frequency sweep test, and multiple stress creep recovery test. The chemical composition changes during aging were then analyzed by Fourier transform infrared spectroscopy and gel permeation chromatography. Finally, the phase morphology during thermal aging was observed by fluorescence microscopy. The results showed that compared with the degradation of CR, the oxidative aging of the asphalt binder played a dominant role in the process. Not only did PEW and PAW attach to the asphalt surface in the form of crystallization to prevent its reaction with oxygen but they also promoted the dissolution of CR, and released polymerization chains, thereby enhancing the antiaging properties of CR-modified asphalt. Furthermore, the antiaging of PAW/CR-modified asphalt was better than that of PEW/CR-modified asphalt, because the amide group of PAW reacted with CR-modified asphalt to form a polymer structure.

The effect of Polyethylene Terephthalate (PET) plastic addition to AC-WC in a wet mixture on increase of asphalt stability

PET (Polyethylene Terephthalate) plastic is one of the most common types of plastic used in Indonesia. Its existence has contributed significantly to various sectors, including the food and beverage, cosmetic, pharmaceutical, and other consumer product packaging industries. However, the use of PET plastic also creates a number of impacts that need to be considered. PET (Polyethylene Terephthalate) plastic has become an attractive alternative in the construction industry in Indonesia, particularly in its use as an asphalt mixture in road construction. This study aimed to determine the effect of the addition of PET waste to the asphalt on the value of Marshall characteristics as well as the optimum asphalt content and plastic content in the AC - WC mixture. Basic testing of 4 %, 5 %, and 6 % (by weight of asphalt) PET plastic mixture with wet mixing method where PET plastic is put into hot asphalt and stirred until homogeneous. Marshall test data will go through Formality Test, Homogeneity Test, Two-Way ANOVA, Duncan Test, and Correlation Regression Analysis to get the 3D graph equation. The result is that PET plastic affects the asphalt mixture by increasing the stability value and MQ value, for flow, VFB, and VMA values have decreased. VIM value increased at 4 % level and decreased at 6 % level. From the ribbon graph, the optimum asphalt content for each percentage of PET content is obtained, namely 4 % PET KAO value of 6.2 %, 5 % PET KAO 6.25 %, and 6 % KAO 6.28 %. It can be concluded that the mixing of PET with asphalt in AC-WC mixtures can be maximum if the right percentage combination of asphalt and PET content. From the 3D Graphic Method, it results that the maximum use of plastic PET is at a content of 5.40 %, and an asphalt content of 6.35 %, will produce an asphalt stability of 1714.232 kN

Bird strike tests, analyses, and design optimisation of a tilt-rotor aircraft composite inlet

Collisions of aircraft with foreign objects are very common phenomena, so they must be anticipated, and their consequences must be individually checked. Since these incidents can result in severe engine damage and the engine is the aircraft's only thrust-providing system, the effect of bird strikes on engine air intakes and similar systems must be investigated and mitigated with special attention. Principally for tilt-rotor convertible aircraft, this effect is crucial in terms of operational safety, flight mechanics and overall aircraft control. The objective of this work is to demonstrate the durability of the composite air intake for a new tilt-rotor aircraft, which is experimentally verified on components of basic geometric shapes such as plate and cylindrical section. Based on computer-supported simulations, which are correlated with the basic tests, the consequences of the impact on the real air-duct were analysed and potentially dangerous regions were found. Sizing and optimisation was carried out and a design improvement proposal was developed.

Faktor-Faktor yang Mempengaruhi Pendapatan Pengrajin Anyaman Lontar di Desa Aeramo Kecamatan Aesesa Kabupaten Nagekeo

This study aims to determine the effect of capital, labor, work experience and education on the income of palm woven craftsmen in Aeramo Village, Aesesa District, Nagekeo Regency through data sourced from palm woven craftsmen with calculations using the SPSS Program. The analysis technique used is multiple linear regression. To calculate the multiple linear regression equation, the data must meet the basic assumption test, namely through hypothesis testing. The coefficient value of the capital variable is 0.521 with tcount table (4.866 > 2.048), the coefficient value of the labor variable is 0.404 with tcount > table (4.061 > 2.048), the coefficient value of the work experience variable is 0.224 with tcount > ttable (2.891 > 2.048) and education variable coefficient value is 0.362 with tcount > ttable (2.715 > 2.048). Then for the F test, the value of Fcount Ftable (11.348 2.99).

‘’Wait and See’’ as a Treatment Option for a Rathke’s Cleft Cyst Apoplexy in Pediatric Population: A Case Report

Introduction: Rathke cleft cyst apoplexy is exceedingly rare, particularly in infants. The most prevalent clinical manifestations include headaches, visual field defects, and endocrine dysfunction. Treatment options range from surgery to conservative methods, taking into consideration the balance of benefits and risks, especially during critical life stages such as childhood. Case Presentation: We present the case of a 12-year-old boy admitted due to the recent onset of headaches and diabetes insipidus. Magnetic resonance imaging revealed Rathke cleft cyst apoplexy. Given the absence of compressive symptoms in a child at the early stages of puberty and without abnormalities in basic endocrine tests, a conservative strategy was employed, involving regular clinical, biological, and radiological follow-ups. The child experienced normal puberty without any endocrine deficiencies except for a partial growth hormone deficiency. Conclusions: For clinically asymptomatic children diagnosed with Rathke's cleft cyst apoplexy, adopting a conservative management approach is recommended, provided there is thorough clinical, biological, and radiological surveillance.

Educational Data Mining: Multiple Choice Question Classification in Vocational School

Data mining on student learning outcomes in the education sector can overcome this problem. This research aimed to provide a solution for selecting quality multiple choice questions (MCQ) using the results of students’ mid-semester exams in vocational high schools using a Data Mining approach. The research method used was the Cross-Industry Standard Process for Machine Learning (CRISP-ML) model. Steps to assess the accuracy of analyzing the difficulty level of questions based on student profile data and midterm test results. The data used in this research were the findings of basic computer tests on mid-term exams in mathematics disciplines at vocational high schools. This research used several classification algorithms, including SVM, Naive Bayes, Random Forest, Decision Three, Linear Regression, and KNN. The results of evaluating the classification

Beyond a spec: assessing heterogeneity in the unregulated opioid supply

BackgroundDrug checking services aim to provide compositional information for the illicit drug supply and are being employed in public health responses to extreme rates of overdose associated with fentanyl within street opioids. The technologies used within these services range from basic qualitative tests, such as immunoassay test strips, to comprehensive quantitative analyses, such as mass spectrometry. In general, there is concern that heterogeneity of a drug mixture adds significant uncertainty when using drug checking results based on a small subsamples. The presence of hot spots of active drug components in this context is often termed the ‘chocolate chip cookie effect’. Establishing the limitations of the service are essential for interpretation of the results.MethodsThis study assesses the consequence of drug heterogeneity and sampling of consumer level opioid purchased in Victoria, British Columbia (n=21\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$n=21$$\\end{document}, 50–100 mg each) on quantitative fentanyl results determined from testing with paper spray mass spectrometry.Results:Using descriptive statistics, such as relative standard deviation and interquartile range, the results demonstrate varied distributions of fentanyl concentrations within a single drug batch. However, the presence of hot spots, defined as outliers, were relatively rare.ConclusionsThis study found that the variability in fentanyl concentration from drug heterogeneity and sampling is greater than that attributed to the analytical technique. On a practical level, this provides data to help guide communication of limitations of drug checking services, supporting the aim of trust and transparency between services and people who use drugs. However, if drug checking services continue to be restricted from fully engaging with the reality of manufacturing, buying, selling, mixing and dosing practices, the accuracy, usefulness, and impact will always be limited.

Cost-effectiveness of screening for chronic kidney disease using a cumulative eGFR-based statistic.

Routine screening for chronic kidney disease (CKD) could enable timely interventions to slow down disease progression, but currently there are no clinical guidelines for screening. We aim to evaluate the cost-effectiveness of screening for CKD using a novel analytical tool based on a cumulative sum statistic of estimated glomerular filtration rate (CUSUMGFR). We developed a microsimulation model that captured CKD disease progression, major complications, patients' awareness, and treatment adherence for a nationally representative synthetic cohort of age ≥ 30 years in the United States. In addition to the status quo with no screening, we considered four CUSUMGFR-based universal screening policies by frequency (annual or biennial) and starting age (30 or 60 years), and two targeted annual screening policies for patients with hypertension and diabetes, respectively. For each policy, we evaluated the total discounted disability-adjusted life years (DALYs) and direct health costs over a lifetime horizon and estimated the incremental cost-effectiveness ratio (ICER). We further performed one-way and probabilistic sensitivity analyses to assess the impact of parameter uncertainty. Compared with the status quo, all the CUSUMGFR-based screening policies were cost-effective under the willingness-to-pay (WTP) range of $50,000 -$100,000, with the estimated incremental cost-effectiveness ratios (ICERs) ranging from $15,614/DALYs averted to $54,373/DALYs averted. Universal annual screening with starting age of 30 was the non-dominated policy on the cost-effectiveness frontier under the WTP of approximately $25,000. Adding more recent treatment option of sodium-glucose cotransporter-2 (SGLT2) inhibitors to the treatment regimen was found to be cost-saving. Among the most influential model parameters, variation in the CKD progression rate, adherence, and testing cost resulted in the highest variability in model outcomes. CUSUMGFR-based screening policies for CKD are highly cost-effective in identifying patients at risk of end stage kidney disease in early stages of CKD. Given its simple requirement of a basic blood test, the CUSUMGFR-based screening can be easily incorporated into clinical workflow for disease monitoring and prevention.

Analisis Pengaruh Sektor Pariwisata Dalam Pembangunan di Kabupaten Nagekeo

This study aims to determine the influence of the tourism sector on development in Nagekeo Regency through data sourced from the Nagekeo Regency Tourism Office with calculations using the SPSS 23 Program. The analysis technique used is multiple linear regression. To calculate the multiple linear regression equation, the data must meet the basic assumption test, namely through the classical assumption test and hypothesis testing. The results of this study indicate that: the first variable of the hotel and restaurant tourism sector tax has a positive effect on the development variable. This is evidenced by the results of the individual parametric significance test (t test). The value of tcount ttable (5.636 2.015). The two variables of employment have a positive effect on the development variable with a value of tcount ttable (3.215 2.015). Then for the F test, the value of Fcount Ftable (9.529 5.79). This means that the tourism sector tax and employment together have a significant effect on development. The development of the tourism sector is directed at the development of the hotel or lodging and restaurant sectors around community-based tourist destinations.

Diagnosis and Treatment of Chronic Urticaria: The Importance of Autoimmune Aspects and Comorbidity

The study aimed to conduct a comprehensive systematic review of the literature on the autoimmune mechanisms associated with chronic spontaneous urticaria (CSU) in adults, explore the association between chronic urticaria (CU) and autoimmune disorders, analyze two case reports, and develop a diagnostic algorithm considering the autoimmune pathogenesis.
 Materials and Methods. The literature review was conducted to study the mechanisms underlying autoimmune CU. Two case reports were analyzed and a diagnostic algorithm for patients suspected of autoimmune urticaria was formulated.
 Results. CU significantly impairs patients’ quality of life, posing problems in daily activities and is often associated with concomitant autoimmune diseases. Though the pathogenesis of CSU remains incompletely understood, in recent years, there has been significant progress in understanding the pathophysiology of this condition, prompting researchers to explore new agents, especially biological ones, in cases with severe refractory urticaria. We have developed a diagnostic algorithm aimed at improving the management tactics for CSU and autoimmune pathology, that involves a thorough collection of complaints, medical history, performing a series of basic laboratory tests for specific markers of autoimmune disorders, and expanding their spectrum with detailed differential diagnostics.
 Conclusions. CU is an important medical and social issue that requires an interdisciplinary personalized approach to patients. The diagnosis of the condition involves a comprehensive approach, considering potential concomitant autoimmune disorders and detailed laboratory investigations, especially in cases refractory to standard second-generation antihistamine therapy. The treatment of CU, specifically the stepwise therapy protocol based on symptom severity and response to treatment and aimed at reducing symptoms, improving patients’ quality of life, and achieving CU remission, is outlined in various national and international guidelines, and is carried out gradually, involving three lines of therapy.

Estimation of cognitive impairment in chronic pain patients and characteristics of estimated mild cognitive impairment.

Patients with chronic pain suffer from psychological effects such as anxiety due to the pain itself. Pain can not only impair activities of daily living (ADL) and quality of life (QOL), but also impair cognitive function. Therefore, in this study, we aimed to estimate the cognitive function of chronic pain patients using a deep neural network (DNN) model that has already been implemented in society. We investigated the characteristics of patients presumed to have mild cognitive impairment (MCI) and, at the same time, verified the relationship with the questionnaire commonly used in chronic pain research, which is administered by 43 university affiliated hospitals and medical institutions participating in the chronic pain research group of the Ministry of Health, Labor and Welfare in Japan (assessment batteries). The study included 114 outpatients from a multidisciplinary pain clinic, and we estimated their Mini-Mental State Examination (MMSE) scores based on age and basic blood test data (23 items). Furthermore, we classified the estimated MMSE scores of chronic pain patients into two groups based on a cutoff score of 27, which indicates MCI, and compared the blood data and assessment batteries. Additionally, we used a control group of 252 healthy adults aged 45 years or older who visited a dementia prevention outpatient clinic for comparison with the MMSE scores of chronic pain patients. The MMSE scores in chronic pain patients were below the cutoff for MCI. When classified into two groups based on the estimated MMSE score of 27 points, WBC, RBC, Hb, Hct, PLT, UA, BUN, creatinine, Triglyceride, and γ-GT were significantly higher in the blood data. In the MCI group, PDAS values were significantly lower. Furthermore, only in the non-MCI group, a significant correlation was found between the estimated MMSE value and BPI, PDAS, and Locomo. The estimated MMSE scores were significantly lower in chronic pain patients than in healthy adults (p = 0.04). Patients with chronic pain may exhibit cognitive impairment due to systemic metabolic disturbances. This suggests that chronic pain affects activities of daily living, resulting in systemic metabolic disorders.

Clinical characteristics and prognosis of 8 cases of severe infant botulism

Objective: To summarize the clinical characteristics and prognosis of severe infant botulism and evaluate the therapeutic effect of botulinum antitoxin in the pediatric intensive care unit (PICU). Methods: The clinical data of 8 cases diagnosed with infantile botulism were retrospectively analyzed in the PICU of Beijing Children's Hospital from October 2019 to August 2023. Data of basic demographic information, clinical manifestations, laboratory tests, treatment and prognosis of each child were collected and analyzed using descriptive statistical methods. Results: Eight laboratory-confirmed cases of infant botulism were included in this study, all of which were male infants with an age of 6.0 (3.3,6.8) months. Three of the children were from Inner Mongolia Autonomous Region, 2 of them were from Hebei, and the other 3 were from Beijing, Shandong and Xinjiang Uyghur Autonomous Region, respectively. All the patients were previously healthy. In 4 of these cases, the possible cause was the ingestion of either honey and its products or sealed pickled food by the mother or child before the onset of the disease. The first symptom was poor milk intake (4 cases), followed by shallow shortness of breath (7 cases), limb weakness (7 cases) and so on. The typical signs were bilateral dilated pupils (8 cases) and decreased limb muscle strength (8 cases). The main subtype was type B (7 cases), and only 1 case was classified as type A. Six of the children were treated with antitoxin therapy for a duration of 24 (19, 49) d. Seven of them had invasive mechanical ventilation. All the patients survived upon discharge with a follow-up period of 29 d to 3 years and 8 months. Six patients had fully recovered, and 2 recently discharged patients were gradually recovering. Conclusions: For infants with suspected contact or ingestion of botulinum and presented with bilateral pupillary paralysis, muscle weakness and clear consciousness, the stool should be collected for diagnostic testing using a mouse bioassay as soon as possible. Type B was the most common type. The antitoxin treatment was effectiveness and the prognosis was well.

Unlocking the Potential of Tropical Fruit Waste to Develop a Biobased Material: An Environment-Friendly Approach

For the sustainable fashion manifesto, biobased material is a novel creation that is made from leftovers and growing biological cells. As the need to develop sustainable biomaterials is on the rise many researchers have focused their studies on microbes and other biological organisms such as plants to offer cleaner, greener processes and entirely new products. The majority of leather items are produced from the skins of cows and calves, that are killed for their flesh. Bio-based materials with Tropical fruit waste were developed using Bacterial Cellulose (Gluconacetobacter) and leftover peels and rinds of mango, papaya and jackfruit. For the production of Bacterial Cellulose (BC), the use of agricultural leftovers can be a cheap and sustainable method. The basic physical tests show that matrices with BC have higher physical and abrasion resistance compared to the other samples. The research indicates that the presence of BC in the matrix increases the biobased material's strength and elongation twofold. The manufacturing processes are using up the natural resource and cause negative environmental effects, this can be reduced by using waste as raw materials. This study has opened new ways of creating biomaterials without using up resources and meeting consumers' sustainability concerns.

Association of epicardial fat volume with subclinical myocardial damage in patients with type 2 diabetes mellitus.

In type 2 diabetes mellitus (T2DM) patients, left ventricular systolic dyssynchrony (LVSD) with normal left ventricular ejection fraction (LVEF) and normal myocardial perfusion could referred to as subclinical myocardial damage, which is difficult to diagnose at an early stage. Epicardial adipose tissue, a distinctive heart-specific visceral fat, is closely related to various cardiovascular diseases. The objective of this study was to investigate the correlation between epicardial fat volume (EFV) and subclinical myocardial damage in T2DM patients. This retrospective cross-sectional study included 117 T2DM patients with normal myocardial perfusion by single photon emission computed tomography-computed tomography (SPECT-CT) and normal LVEF by echocardiography. The study was conducted from January 2018 to December 2022. Patient data were collected through electronic medical records including basic patient information, medical history, laboratory tests, and medication data. The EFV was quantified through a non-contrast CT scan. Quantitative indicators of LVSD including phase standard deviation (PSD) and phase histogram bandwidth (PBW) were obtained through phase analysis of the gated rest myocardial perfusion imaging (MPI). Additionally, 83 healthy individuals at the same time were selected to gain the reference threshold of LVSD indicators (13.1° for PSD and 37.6° for PBW). Univariate and multivariable logistic regression models were performed to analyze factors influencing LVSD. A generalized additive model (GAM) was applied to explore the relationship between EFV and LVSD. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of EFV for LVSD. Among all patients, 32 (27.4%) patients had LVSD. Compared with the non-LVSD group, the body mass index (BMI) and EFV were higher in the LVSD group (25.83±2.66 vs. 23.94±3.13 kg/m2; 142.41±44.17 vs. 108.01±38.24 cm3, respectively, both P<0.05). Multivariate regression analysis revealed that EFV was independently associated with LVSD [odds ratio (OR) =1.19; 95% confidence interval (CI): 1.06-1.34; P=0.003]. Age, BMI, incidence of hypertension, and LVSD were increased with tertiles of EFV (all P<0.05). The GAM indicated a linear association between EFV and LVSD. The ROC curve analysis concluded that the area under the curve (AUC) of EFV for predicting subclinical myocardial damage in T2DM patients was 0.732 (95% CI: 0.633-0.831, P<0.001), with the optimal threshold of 122.26 cm3, sensitivity of 71.9%, and specificity of 69.4%. EFV is an independent risk factor for LVSD in T2DM patients with normal LVEF and normal MPI, which could potentially serve as a novel imaging marker and a potential therapeutic target for subclinical myocardial damage.

Influence of different test methods on the accuracy of high current busbar insulation resistance

Compared with the traditional cable, the high current busbar fully embodies its superiority in the process of current transmission, and thus its insulation performance test is of great significance to the safe operation of the line. In this paper, the insulation resistance of the high current busbar is measured by the basic test principle and the voltage injection test method respectively, and then the accuracy and precision of the two test methods are compared. The test results show that the relative error of insulation resistance of positive and negative busbar fluctuates in the range of 0.35%-4.20% and 0.10%-3.33%, respectively, while that of voltage injection test fluctuates in the range of 0.60%-2.80% and 1.10%-1.80%, respectively. Regardless of the basic test principle or voltage injection test, the relative error of insulation resistance in the high current busbar is less than 5%, and the voltage injection test method is more accurate. Compared with the basic test principle, the maximum relative error of Rn and Rp is reduced by 0.87% and 1.00% respectively.

Application of computer vision technology in surface damage detection and analysis of shedthin tiles in China: a case study of the classical gardens of Suzhou

In computer artificial intelligence, there is great potential in research on the protection of Suzhou's traditional gardens, a world cultural heritage site. As a special material in Suzhou's traditional garden architecture, shedthin tile is widely used in roof base laying and is one of the important materials for building roofs. However, professionals need to reach the roof and spend much time and effort assessing the damage before repairing it. Therefore, the main goals of this study are to investigate a machine learning-based method for finding targets and determining the type of surface damage on a shedthin tile using the YOLOv4 model trained in this study. Using 500 shedthin tile on-site photos as training samples, the model was trained for 750 epochs. The main results of this study are as follows: (1) An object detection method based on machine learning can efficiently and accurately identify damage content, overcoming the manpower and time–cost limitations of traditional assessment methods. (2) The detection model in this study has an accuracy of 85.89% for water stain recognition of shedthin tiles, 93.29% for surface scaling, 87.37% for color aberration, and 96.15% for too wide a gap. The comprehensive accuracy is 90.20%, which meets the basic testing requirements. (3) The model demonstrated its robustness and reliability in complex environments in application tests in actual scenarios, providing a methodological reference for computer vision and target detection technology in cultural heritage protection.