Test Method Research Articles

Multiple hypothesis testing in cognitive IoT sensor network

Recent Internet of Things (IoT) research aims to develop generic objects to learn, reason, and perceive their environment. Therefore, a new area has emerged known as cognitive IoT (CIoT). The cognitive Internet of Things integrates IoT with intelligence and behaves as well as humans through intelligent functionality. Several inferential tasks in CIoT require multiple hypothesis testing. The situation becomes cumbersome when the data is massive and heterogeneous. Thus, this research suggests a novel technique for multiple-hypothesis testing that uses a copula function to deal effectively with massive heterogeneous data. In addition, these data may contain missing or corrupted entries. Hence, it introduced probabilistic clustering, which reduces model inefficiency and takes control over the false discovery rate (FDR). Most of the variance from each cluster was extracted using kernel principal component analysis (KPCA) to reduce the processing burden at the fusion centre. Subsequently, it computes the p-value of each cluster's first principal component data and employs the Bonferroni method for multiple hypothesis testing. Finally, this research study evaluates the performance of the proposed algorithm on six-month environmental data, revealing that the proposed technique is efficient in terms of accuracy and computation time compared to other methods in the presence of massive heterogeneous data.

Application of Linear Regression in GDP Forecasting

Gross Domestic Product (GDP) is the core indicator of national economic accounts, which reflects the economic capacity of a region. It is necessary to have an accurate forecast of GDP. GDP prediction plays an important role in formulating economic policies. By predicting the growth trend of GDP, the government can make correct adjustments and regulate economic activities. This paper takes Guangdong Province and Shandong Province as examples, aiming to establish their GDP models respectively, and obtains their important economic factors on the basis of the models. Firstly, the correlation test and stepwise regression method were used to screen out the variables with significant impact on GDP, and then ridge regression was used to solve the multicollinearity to make the model more accurate. Finally, the similarities and differences of important economic factors in the two provinces were compared. The important economic factors of these two provinces can reflect the characteristics of the economic development of China's north and south, which is conducive to promoting the coordinated development of regional economy and win-win cooperation.

Sliding motility of Bacillus cereus mediates vancomycin pseudo-resistance during antimicrobial susceptibility testing.

The glycopeptide vancomycin is the antimicrobial agent-of-choice for the treatment of severe non-gastrointestinal infections with members of Bacillus cereus sensu lato (s.l.). Recently, sporadic detection of vancomycin-resistant phenotypes emerged, mostly for agar diffusion testing such as the disc diffusion method or gradient test (e.g. Etest®) method. In this work, we were able to disprove a preliminarily assumed high resistance to vancomycin in an isolate of B. cereus s.l. using broth microdilution and agar dilution. Microscopic imaging during vancomycin susceptibility testing showed spreading towards the inhibition zone, which strongly suggested sliding motility. Furthermore, transcriptomic analysis using RNA-Seq on the nanopore platform revealed several key genes of biofilm formation (e.g. calY, tasA, krsEABC) to be up-regulated in pseudo-resistant cells, substantiating that bacterial sliding is responsible for the observed mobility. Down-regulation of virulence (e.g. hblABCD, nheABC, plcR) and flagellar genes compared with swarming cells also confirmed the non-swarming phenotype of the pseudo-resistant isolate. The results highlight an insufficiency of agar diffusion testing for vancomycin susceptibility in the B. cereus group, and reference methods like broth microdilution are strongly recommended. As currently no guideline mentions interfering phenotypes in antimicrobial susceptibility testing of B. cereus s.l., this knowledge is essential to obtain reliable results on vancomycin susceptibility. In addition, this is the first report of sliding motility undermining accurate antimicrobial susceptibility testing in B. cereus s.l. and may serve as a basis for future studies on bacterial motility in susceptibility testing and its potential impact on treatment efficacy.

P.153 Utility of neurophysiology in the diagnosis of tethered cord syndrome (TCS)

Background: Tethered cord syndrome, a condition in which the spinal cord stretches as a child grows, can cause various clinical symptoms. Occult TCS (OTCS) is a condition where a child displays some or many clinical symptoms of TCS, but no radiographic abnormality confirms the presence of a tethered cord (1-4). Diagnosis of OTCS in children is invasive and multi-factorial. The current diagnostic approach involves three main factors- clinical signs and symptoms, radiographic evidence, and motor evoked potentials (MEPs) tested under general anesthesia. Transcranial magnetic stimulation (TMS) is a non-invasive testing method for OTCS. It can replace MEPs, which are conducted under general anesthesia. Methods: We will conduct a case-control series of children at our center who have undergone TMS. We will characterize the children who have TCS and suspected OTCS and detail the children’s current diagnosis methods and outcomes in a technical note. We will then compare their pre-operative and post-operative data. Results: So far, we have conducted TMS on 10 children to help diagnose occult TCS. Conclusions: This approach is a novel and effective way to improve the accuracy of diagnosis in children, potentially preventing unnecessary surgery, or detecting patients who would otherwise suffer from the condition.

Enhancing the continuing willingness of Chinese college students to engage in volunteer services for older adults

BackgroundThe ageing population presents a substantial challenge to conventional care services for older adults in China. College students' voluntary service constitutes an integral component of youth volunteerism, and investigating their continuing willingness to engage in volunteer services to benefit older adults holds immense importance for fostering a stable and enduring framework for China's older adults' care team. MethodDrawing on the extended theory of reasoned action, this study establishes an analytical framework to examine the willingness of Chinese college students to engage in volunteer services for older adults. Using micro-survey data, we employ structural equation modelling and the bootstrap mediation effect test method to empirically investigate the influencing mechanism behind this willingness. Results(1) Attitude has the strongest influence on the continuing willingness of Chinese college students to engage in volunteer services for older adults, and plays a mediating role between subjective norms and continuing willingness to engage in volunteer services, which reveals the special role of attitude in the continuing engagement of Chinese college students in volunteer services for older adults. (2) Personality trait has a substantial positive impact on Chinese college students’ willingness to engage continuously in volunteer service for older adults, and subjective norms and attitudes have a chain mediating effect in this influence relationship. (3) The theoretical model constructed in this study is reasonable, reliable and robust. ConclusionThis study elucidates the potential relationship between attitude, subjective norms, personality traits and the willingness to engage in volunteer services, offering a novel perspective for understanding the continuing willingness of Chinese college students to engage in volunteer services for older adults. Furthermore, it highlights the value of incorporating the extended theory of reasoned action into the policy design of college students’ engagement in such services.

Answers to Your Resistivity Questions and Helpful Findings to Develop a Robust Resistivity Specification

Many states are currently in the process of evaluating the use of surface resistivity (SR) or bulk resistivity (BR) tests to assess permeability of concrete in lieu of the standard test method for electrical indication of concrete’s ability to resist chloride ion penetration (AASHTO T 277 and ASTM C1202) which is commonly referred to as the rapid chloride permeability test (RCPT). A few states, such as Louisiana and Maine, implemented resistivity testing in their specifications many years ago. As with any test method implementation, it is important to learn from data generated and experience gained to further refine the specifications in respect of both testing protocols and the specification limits. In this paper, the Federal Highway Administration’s Mobile Concrete Technology Center SR and BR data from 30 field projects in 25 states is analyzed to provide information that could be helpful to agencies as they specify or improve their specifications with respect to resistivity testing. This paper attempts to answer questions related to 1) change in resistivity testing results with age, 2) range and variability of resistivity data from mainline paving mixtures, 3) comparison of test results between SR and BR data, 4) comparison of resistivity data gathered with equipment from various vendors, and 5) use of 28 versus 56 day data.

Pozzolanic Reactivity of High-Alkali Supplementary Cementitious Materials and Its Impact on Mitigation of Alkali-Silica Reaction

The growing scarcity of conventional supplementary cementitious materials (SCMs) such as Class F, Class C fly ashes, and slag has necessitated exploring alternative SCMs previously considered suboptimal. In particular, high-alkali SCMs are often avoided because of the potential concern that their alkali content could release into the concrete pore solution, thus exacerbating the potential for alkali-silica reaction (ASR). However, preliminary research indicates that not all high-alkali SCMs are deleterious, and some can effectively suppress the ASR expansive reaction when used in sufficient dosage levels. This study evaluates the feasibility of using high-alkali SCMs, such as high-alkali natural pozzolans and reclaimed fly ashes, focusing on their pozzolanic reactivity and the correlation between the reactivity and their ASR mitigation performance. The pozzolanic reactivity of the SCMs was evaluated by the R3 test per ASTM C1897 and strength activity index test per ASTM C311. Thermogravimetric analysis was used to determine the calcium hydroxide consumption by the SCMs. ASR mitigation performance of SCMs was evaluated in accordance with American Association of State Highway and Transportation Officials (AASHTO) T380 miniature concrete prism test. Additionally, pore solution expression and analysis of paste specimens were conducted to determine the correlation between the total alkali and the released alkali levels into the pore solution. Based on the results of this study, all SCMs indicated high pozzolanic reactivity; however, individual performance varied by test method. Ultimately, the high-alkali SCMs, particularly natural pozzolans, did not appear to release any significant levels of alkalis into the pore solution readily and, therefore, show potential for ASR mitigation when used in sufficient dosage levels.

Modern trends in the application of thermoelectric method in non-destructive testing (review)

The article provides an overview of the main directions of using the thermoelectric testing method in various spheres of the national economy. The thermoelectric method is most widely used in industry. There are publications on the application of the thermoelectric method for quality monitoring of turning and friction stir welding. It is shown that the thermoelectric method makes it possible to increase the reliability of testing and, based on testing data, ensure optimal modes of the technological process of metalworking and welding. A number of articles are devoted to the application of the thermoelectric method to plastic deformation testing, the dependence of thermal EMF on the degree of plastic deformation is revealed. Recently, publications have appeared on the application of the thermoelectric method to testing the thermal resistance of the design “housing of a power semiconductor device-thermal interface-cooling radiator”. This design is very widespread in electronic equipment. In addition, there are articles on the use of the thermoelectric method to testing the transient resistance of contacts in the power supply network. It is shown that with an increase in contact resistance, the value of thermal EMF increases proportionally, which can be used to prevent emergencies in the power supply network. The thermoelectric method has also been successfully applied to diagnose the degree of titanium flooding. The dependence of the thermal EMF value on the degree of hydrogenation has been revealed. The use of the thermoelectric method is not limited to the field of industrial production. The thermoelectric method is successfully used in medicine for the undetectable detection of nucleic acid sequences, for the temperature diagnosis of human teeth, as well as for the diagnosis of inflammatory processes in the human body.

Experimental Study on Interface Thermal Resistance of Heat Dissipation Channel in Low-Temperature Detector

Abstract To achieve a good heat dissipation effect in the heat dissipation channel of the low-temperature detector, it is necessary to study the thermal conductivity performance of GD414C and indium foil between detector and thermal conductive aluminum block. Based on the experimental principle and referring to the ASTM D-5470 testing method, a set of interface thermal resistance experimental testing equipment is designed. The experiment comparatively studies the relationship between the temperature difference between detector and thermal conductive aluminum block (TCAB) under different power and thermal conductive fillers. The experimental results show that when GD414C is filled between detector and thermal conductive aluminum block, the total thermal resistance is 0.728 ℃/W. When 0.1-mm-thick indium foil is filled, the total thermal resistance is 0.235 ℃/W. When 0.2-mm-thick indium foil is filled, the total thermal resistance is 0.123 ℃/W. Therefore, 0.2-mm-thick indium foil should be selected as the thermal conductive filler.

Determination of complex Poisson’s ratio of asphalt binders using torsion-tension tests in a dynamic shear rheometer

A novel test method for measuring the Poisson’s ratio of asphalt binders using a Dynamic Shear Rheometer (DSR) equipped with a linear drive is presented. The paper describes the preparation of homogeneous and isotropic cylindrical binder specimens, their loading into the DSR, and the subsequent measurement of the absolute complex shear modulus |G*|, and the complex elastic modulus |E*|. Both moduli are obtained from the same specimen so the complex Poisson’s ratio, |υ*|, can be measured indirectly as a function of temperature and frequency. This is illustrated for three different samples of plain asphalt binders: hard 30/45 binder, standard 50/70 binder, and soft 70/100 binder.

Comprehensive analysis of thalassemia alleles (CATSA) based on third-generation sequencing is a comprehensive and accurate approach for neonatal thalassemia screening

Thalassemia is one of the most common and damaging monogenic diseases in the world. It is caused by pathogenic variants of α- and/or β-globin genes, which disrupt the balance of these two protein chains and leads to α-thalassemia or β-thalassemia, respectively. Patients with α-thalassemia or β-thalassemia could exhibit a severe phenotype, with no simple and effective treatment. A three-tiered strategy of carrier screening, prenatal diagnosis and newborn screening has been established in China for the prevention and control of thalassemia, of which the first two parts have been studied thoroughly. The implementation of neonatal thalassemia screening is lagging, and the effectiveness of various screening programs has not yet been demonstrated. In this study, hemoglobin capillary electrophoresis (CE), hotspot testing method, and third-generation sequencing (TGS) were used in the variant detection of 2000 newborn samples, to assess the efficacy of these methods in neonatal thalassemia screening. Compared with CE (249, 12.45 %) and hotspot analysis (424, 21.2 %), CATSA detected the largest number of thalassemia variants (535, 26.75 %), which included 24 hotspot variants, increased copy number of α-globin gene, rare pathogenic variants, and three unreported potentially disease-causing variants. More importantly, CATSA directly determined the cis–trans relationship of variants in three newborns, which greatly shortens the clinical diagnosis time of thalassemia. CATSA showed a great advantage over other genetic tests and could become the most powerful technical support for the three-tiered prevention and control strategy of thalassemia.

Analisis Reaksi Pasar Terhadap Keterlambatan Penyampaian Laporan Keuangan Interim

The late submission of interim financial reports causes companies listed on the Indonesia Stock Exchange (IDX) to pay a fairly large amount of fines. The Financial Services Authority (OJK) issued regulations for companies going public to report and publish audited annual financial reports, so that each company must submit accordingly and on time. Therefore, this research aims to determine the comparison of abnormal returns and stock trading volume before and when there is a delay in submitting financial reports. The data used in this research are the financial reports of companies registered on the IDX that are late in submitting financial reports. The results of this research show significant differences in abnormal returns and stock trading volume before and after the delay in submitting interim financial reports. The study uses the average difference test method, with the object of the financial statements of 35 listed companies that have not submitted financial reports for the period 2021 to 2022. After descriptive statistical analysis, there are company values that are recorded as poor in submitting their interim financial reporting. The results showed that there was a significant difference between the performance before and after the company's financial reporting on abnormal returns and stock trading volume on the submission of financial reports.

An improved hidden Markov model with magnetic Barkhausen noise and optimized Gaussian mixture feature for fatigue prediction

Evaluating fatigue states of metallic materials is essential for predicting their failures and ensuring structural safety. Magnetic Barkhausen noise (MBN) analysis, a non-destructive testing method, provides efficient and reliable methods for identifying and categorising material parameters such as hardness and residual stresses. To establish a quantitative relationship between MBN signals and fatigue states, an improved hidden Markov model (HMM) is proposed based on optimised Gaussian mixture features (GMFs) and the Kullback–Leibler (KL) divergence measure for fatigue prediction. The MBN-GMFs replicate the probability characteristics of MBN signals and track the fatigue degradation trend throughout the fatigue life; thus, they are superior to some widely used statistical features. A Gaussian component optimisation algorithm is proposed to automatically adjust the appropriate number of components in the Gaussian mixture model and enhance the representation of MBN-GMFs. Then, the KL divergence is introduced to quantify the similarity and accurately classify the degree of MBN-GMF migration. The HMM is constructed to obtain the probability transfer relationship between the observations and states and obtain accurate fatigue predictions. Experiments on two 20R metallic materials at three excitation frequencies are conducted to collect the MBN signals. The experimental results and comparisons indicate that the proposed HMM can accurately predict fatigue states and provide a practical and robust analysis tool for MBN-based fatigue predictions.

Liver function and portal-systemic shunting quantified by the oral cholate challenge test and risk for large oesophageal varices.

The quantitative HepQuant SHUNT test of liver function and physiology generates a disease severity index (DSI) that correlates with risk for clinical complications, such as large oesophageal varices (LEVs). A derivative test, HepQuant DuO, generates an equivalent DSI and simplifies testing by requiring only oral administration of the test solution and two blood samples at 20 and 60 min. Since the DSIs measured from DuO and SHUNT are equivalent, we compared the diagnostic performance for large oesophageal varices (LEVs) between the DSIs measured from DuO and SHUNT tests. This study combined the data from two prospectively conducted US studies: HALT-C and SHUNT-V. A total of 455 subjects underwent both the SHUNT test and esophagogastroduodenoscopy (EGD). DSI scores correlated with the probability of LEVs (p < 0.001) and demonstrated a stepwise increase from healthy lean controls without liver disease to subjects with chronic liver disease and no, small or large varices. Furthermore, a cutoff of DSI ≤ 18.3 from DuO had a sensitivity of 0.98 (missing only one case) and, if applied to the endoscopy (EGD) decision, would have prevented 188 EGDs (41.3%). The AUROC for DSI from DuO did not differ from that of the reference SHUNT test method (0.82 versus 0.81, p = 0.3500). DSI from HepQuant DuO links liver function and physiology to the risk of LEVs across a wide spectrum of patient characteristics, disease aetiologies and liver disease severity. DuO is minimally invasive, easy to administer, quantitative and may aid the decision to avoid or perform EGD for LEVs.

Corporate Social Responsibility of Coal Comodity Industry in Indonesia

The concept of Corporate Social Responsibility (CSR) continues to develop following the rapid development of business models and awareness of various groups regarding CSR issues. The implementation of CSR has been carried out by companies at various levels, from multinational, national to local companies, especially in Indonesia. This research aims to analyze the CSR performance of coal companies in Indonesia by measuring leverage, profitability and company size. The data collection method uses content analysis techniques in annual reports of coal companies listed on the IDX. The testing method uses panel data regression. Hypothesis test results show that company size and probability influence corporate social responsibility (CSR). Meanwhile, leverage shows a positive and significant influence on corporate social responsibility (CSR).

Virtual parameter calibration of pod pepper seeds based on discrete element simulation

In order to achieve numerical optimization of the pod pepper seed sowing device, the contact parameters of pod pepper seeds were calibrated, with the angle of repose used as the response value. A set of discrete element method (DEM) models of pod pepper seeds was developed to simulate the formation of seed repose angles using reverse engineering reconstruction techniques. An eight-factor, three-level response surface experiment based on the Box-Behnken central combination test method was performed to study the effects of various factors on the angle of repose of seeds. The angle of repose obtained from physical experiments with a value of 27.56° was taken as the target value. The optimal combination of parameters is obtained as follows: seed Poisson's ratio of 0.22, seed shear modulus of 15.47 MPa, seed-to-seed static friction coefficient of 0.25, seed-to-seed rolling friction coefficient of 0.67, seed-to-seed collision recovery coefficient of 0.64, seed-to-steel-plate static friction coefficient of 0.55, seed-to-steel-plate rolling friction coefficient of 0.45, and seed-to-steel plate collision recovery coefficient of 0.34. A two-sample t-test of the angle of repose obtained by the cylinder lifting method and the pumping plate method against the target value yielded P > 0.05, indicating the reliability of the simulation experiments.

Hydro-assisted incremental forming (HAIF): A formability-enhanced incremental forming process; presenting an experimental method for determination of forming limits with generalized non-planar stress state

Hydro-assisted incremental forming (HAIF) as a hybrid process of incremental forming and hydromechanical deep drawing with enhanced formability resulted of simultaneous exertion of normal and through thickness stresses is introduced in this paper. Based on this process, a test method is invented for experimental and finite element assessment of forming limits under generalized non-planar stress state. Previous analytical forming limit curves predicted by the present authors are evaluated using experimental tests and finite element simulations and good compatibility is observed. It is again confirmed that application of normal and through thickness stresses enhance formability in all strain paths specially in plane strain mode.

Integration of Design Sprint Method into Mobile Development Application Life Cycle to Create MobilePQI Application Prototype

This study aims to create a mobile-based learning application that can be used to support blended learning. Blended Learning is carried out synchronously, either online using Zoom or Google Meet, or offline in the classroom. asynchronous learning is implemented using MobilePQI Apps. MobilePQI Apps was developed using the Kotlin programming tool and MADLC methodology (Mobile Application Development Life Cycle). MADLC consists of seven stages: Identification; Design; Development; Prototyping; Testing; Deployment; and Maintenance. We use design sprint method and figma to create design prototype, and Kotlin development kit. The testing method used heuristics evaluation which tests 10 usability principles. The number of questions asked was 115, with 5 respondents consisting of 3 students and 3 lecturers. The results of the heuristics evaluation score were 89% of respondents answered YES. That it can be concluded that the 10 usability principles of the prototype was acceptable. The SUS results show a score of 74, which means the application's user interface is in the Good and acceptable category.

Characterisation of a novel AmpC beta-lactamase, DHA-33, resistant to inhibition by cloxacillin

Plasmid-encoded DHA-type AmpCs have been extensively reported in Enterobacterales. The expression of the genes encoding these plasmid-mediated enzymes are inducible and these enzymes are capable of conferring resistance to a wide spectrum of beta-lactams including penicillins and broad-spectrum cephalosporins. The identification of infections caused by AmpC-producing bacteria is a necessity, both for infection control/epidemiology purposes and to inform treatment choices. A common testing method for AmpC production in the clinical laboratory setting is to supplement Mueller-Hinton agar plates used for antibiotic disk diffusion with cloxacillin, a potent inhibitor of AmpC enzymes. Here we describe a novel DHA variant, produced by a clinical Escherichia coli isolate, which is resistant to cloxacillin inhibition.

Experimental Study on Shear Lag Effect of Long-Span Wide Prestressed Concrete Cable-Stayed Bridge Box Girder under Eccentric Load

Based on the engineering background of the wide-width single cable-stayed bridge, the shear lag effects of the cross-section of these bridge box girders under the action of the eccentric load were experimentally studied. The behavior of shear lag effects in the horizontal and longitudinal bridge directions under eccentric load in the operational stage of a single cable-stayed bridge was analyzed by a model testing method and a finite element (FE) analytical method. The results showed that the plane stress calculation under unidirectional live load was similar to the results from spatial FE analysis and structural calculations performed according to the effective flange width described in the design specification. At the position of the main beam near the cable force point of action, the positive stress at its upper wing edge was greatest. At a distance from the cable tension point, the maximum positive stress position trend showed that from the center of the top flange to the junction of the top flange and the middle web to the junction of the top flange and the middle web and the side web. Under eccentric load, the positive and negative shear lag effects on the end fulcrum existed at the same time, and the shear lag coefficient on the web plate was larger than the shear lag coefficient on the unforced side. Due to the influence of constraint at the middle fulcrum near the middle pivot point, positive and negative shear lag effects were significant, and the coefficient variation range was large, resulting in large tensile stress on the roof plate in this area. According to FE analytical results, stress and shear forces of a single box three-chamber box girder under eccentric load were theoretically analyzed, the bending load decomposed into the accumulation of bending moment and axial force, using the bar simulation method, and the overall shear lag effect coefficient λ was obtained and verified.