It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and er...It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and erythropoietic protoporphyria(EPP),which has not been previously documented.CASE SUMMARY We present a rare case of coexisting GS and EPP in a 23-year-old Chinese male with a long history of jaundice and recently found splenomegaly.Serial nonspecific hemolysis screening tests yielded inconsistent results,and investigations for common hemolytic etiologies were negative.However,Levitt’s carbon monoxide breath test,which measures erythrocyte lifespan(the gold-standard marker of hemolysis),demonstrated significant hemolysis,revealing a markedly shortened erythrocyte lifespan of 11 days(normal average 120 days).Genetic testing subsequently confirmed EPP with a homozygous ferrochelatase gene mutation and GS with a heterozygous uridine diphosphate glucuronosyl trans-ferase 1A1 gene mutation.CONCLUSION The rapid,non-invasive Levitt’s carbon monoxide breath test resolved the diagnostic challenge posed by a rare and complex cause of hyperbilirubinemia.展开更多
BACKGROUND Small intestinal bacterial overgrowth(SIBO)is suspected and excluded frequently in functional gastrointestinal(GI)disorders.Children presenting with various esophago-gastro-duodenal(upper GI)symptoms are ra...BACKGROUND Small intestinal bacterial overgrowth(SIBO)is suspected and excluded frequently in functional gastrointestinal(GI)disorders.Children presenting with various esophago-gastro-duodenal(upper GI)symptoms are rarely subjected to investig-ations for SIBO.AIM To estimate the frequency of SIBO in children having functional upper GI sym-ptoms(as cases)and to compare the result of the SIBO status to that of the con-trols.METHODS Children aged 6 to 18 who presented with upper GI symptoms were selected for the study.All children were subjected to upper GI endoscopy before being advised of any proton pump inhibitors(PPIs).Children with normal endoscopy were assigned as cases,and children having any endoscopic lesion were design-ated as controls.Both groups were subjected to a glucose-hydrogen breath test by Bedfont Gastrolyser.RESULTS A total of 129 consecutive children who were naive to PPIs and had normal ba-seline investigations were included in the study.Among them,67 patients had endoscopic lesions and served as the control group,with six cases being excluded due to the presence of Helicobacter pylori in gastric biopsies.Sixty-two children with normal endoscopy results formed the case group.In the case group,35 children(59%)tested positive for hydrogen breath tests,compared to 13 children(21%)in the control group.The calculated odds ratio was 5.38(95%confidence interval:2.41-12.0),which was statistically significant.Further analysis of symptoms revealed that nausea,halitosis,foul-smelling eructation,and epigastric fullness were positive predictors of SIBO.CONCLUSION It is worthwhile to investigate and treat SIBO in all children presenting with upper GI symptoms that are not explained by endoscopy findings.展开更多
Geomechanical properties of rocks vary across different measurement scales,primarily due to heterogeneity.Micro-scale geomechanical tests,including micro-scale“scratch tests”and nano-scale nanoindentation tests,are ...Geomechanical properties of rocks vary across different measurement scales,primarily due to heterogeneity.Micro-scale geomechanical tests,including micro-scale“scratch tests”and nano-scale nanoindentation tests,are attractive at different scales.Each method requires minimal sample volume,is low cost,and includes a relatively rapid measurement turnaround time.However,recent micro-scale test results–including scratch test results and nanoindentation results–exhibit tangible variance and uncertainty,suggesting a need to correlate mineral composition mapping to elastic modulus mapping to isolate the relative impact of specific minerals.Different research labs often utilize different interpretation methods,and it is clear that future micro-mechanical tests may benefit from standardized testing and interpretation procedures.The objectives of this study are to seek options for standardized testing and interpretation procedures,through two specific objectives:(1)Quantify chemical and physical controls on micro-mechanical properties and(2)Quantify the source of uncertainties associated with nanoindentation measurements.To reach these goals,we conducted mechanical tests on three different scales:triaxial compression tests,scratch tests,and nanoindentation tests.We found that mineral phase weight percentage is highly correlated with nanoindentation elastic modulus distribution.Finally,we conclude that nanoindentation testing is a mineralogy and microstructure-based method and generally yields significant uncertainty and overestimation.The uncertainty of the testing method is largely associated with not mapping pore space a priori.Lastly,the uncertainty can be reduced by combining phase mapping and modulus mapping with substantial and random data sampling.展开更多
This study presents the results of a Monte Carlo simulation to compare the statistical power of Siegel-Tukey and Savage tests.The main purpose of the study is to evaluate the statistical power of both tests in scenari...This study presents the results of a Monte Carlo simulation to compare the statistical power of Siegel-Tukey and Savage tests.The main purpose of the study is to evaluate the statistical power of both tests in scenarios involving Normal,Platykurtic and Skewed distributions over different sample sizes and standard deviation values.In the study,standard deviation ratios were set as 2,3,4,1/2,1/3 and 1/4 and power comparisons were made between small and large sample sizes.For equal sample sizes,small sample sizes of 5,8,10,12,16 and 20 and large sample sizes of 25,50,75 and 100 were used.For different sample sizes,the combinations of(4,16),(8,16),(10,20),(16,4),(16,8)and(20,10)small sample sizes and(10,30),(30,10),(50,75),(50,100),(75,50),(75,100),(100,50)and(100,75)large sample sizes were examined in detail.According to the findings,the power analysis under variance heterogeneity conditions shows that the Siegel-Tukey test has a higher statistical power than the other nonparametric Savage test at small and large sample sizes.In particular,the Siegel-Tukey test was reported to offer higher precision and power under variance heterogeneity,regardless of having equal or different sample sizes.展开更多
In recent years,the application scenarios of electrical and electronic products have become increasingly diverse worldwide.The impact of climatic environmental tests on the performance of related products has attracte...In recent years,the application scenarios of electrical and electronic products have become increasingly diverse worldwide.The impact of climatic environmental tests on the performance of related products has attracted much attention,and formulating scientific and reasonable environmental test plans has become an important step to ensure product quality and reliability.展开更多
BACKGROUND Human immunodeficiency virus(HIV)recency testing provides data that can be used to monitor the trend of new HIV infections.The effectiveness of using people identified with recent infection to identify part...BACKGROUND Human immunodeficiency virus(HIV)recency testing provides data that can be used to monitor the trend of new HIV infections.The effectiveness of using people identified with recent infection to identify partners with new HIV infection through partner notification services(PNS)is not well documented.AIM To determine the pooled prevalence of recency testing coverage,recent infection,reclassification(recent to longterm infection)and PNS cascade among newly diagnosed people living with HIV.METHODS PubMed,Cochrane Library and Embase were searched for articles published between January 2018 and November 2024.Studies were included if they reported recency coverage and/or PNS among people newly diagnosed with HIV and used recent infection testing algorithm(RITA).Recency coverage was defined as proportion of people tested using rapid testing for recent infection(RTRI)among those newly diagnosed with HIV.RITA further classifies RTRI results using viral load results(≥1000 copies/mL vs<1000 copies/mL)to confirm recency status.For studies with PNS,we evaluated the cascade:Number of partners elicited,successfully contacted,eligible for HIV testing,tested and HIV diagnosis.PNS effectiveness was measured by proportion of new HIV diagnoses from tested partners.Using random effects models,we computed the pooled estimate of recency outcomes and 95%confidence intervals(CIs).RESULTS Twenty-five studies from 17-low-and middle-income countries were included.Of 276315 newly diagnosed people living with HIV,79864 underwent RTRI with an overall pooled recency coverage of 87%(95%CI:67-96).The pooled prevalence of RTRI and RITA recency were 12%(95%CI:9-16)and 7%(95%CI:4-10),respectively.Pooled prevalence of RTRI reclassification was 34%(95%CI:22-49).Of the recent cases who agreed to PNS,253 partners were elicited with an estimated elicitation ratio of 1:1.6.Among partners elicited,99%were successfully contacted,75%were eligible for testing,68%tested for HIV,and 15%were diagnosed with HIV.CONCLUSION High recency testing coverage among newly diagnosed individuals demonstrates the feasibility of monitoring new HIV infections in LMIC.While PNS yielded moderate HIV diagnoses,its targeted approach remains a critical strategy for identifying undiagnosed cases.展开更多
BACKGROUND Functional abdominal pain disorders(FAPDs)are common gut–brain interaction disorders with unclear pathophysiology.While impaired gastrointestinal motility is thought to play a key role,small intestinal dys...BACKGROUND Functional abdominal pain disorders(FAPDs)are common gut–brain interaction disorders with unclear pathophysiology.While impaired gastrointestinal motility is thought to play a key role,small intestinal dysmotility remains largely unexplored.Orocecal transit time(OCTT),an indirect indicator of small intestinal transit,offers an insight into its potential contribution to FAPD's pathophysiology.AIM To assess OCTT in children with FAPDs compared with healthy children using the lactulose breath hydrogen test.METHODS Thirty-four children(44.1%males,age 5–12 years,mean 7.2±2.4 years)with FAPDs attending North Colombo Teaching Hospital,Ragama,Sri Lanka,were included in the analysis.FAPDs were diagnosed using the Rome IV criteria.None had clinical or laboratory evidence of organic diseases.They were compared with 19 healthy controls(47.1%males,age 5-12 years,mean 7.8±2.7 years)from the same geographical area.OCTT was calculated after an 8-hour fast using a previously validated technique.Breath hydrogen levels were measured at baseline and 15-minute intervals for 180 minutes post-lactulose ingestion(10 g in 10%solution).At each time point,3 breath samples were collected and analyzed.OCTT was quantified as the time taken to achieve a sustained breath hydrogen increase>10 parts per million above baseline.Symptoms were recorded using the Rome IV questionnaire,and symptom severity was graded on a 0-4 Likert scale.RESULTS Patients with FAPDs had increased OCTT(median,90 minutes;interquartile range,75-120 minutes)compared to controls(median,75 minutes;interquartile range,60-75 minutes)(P=0.0045,Mann-Whitney U-test).Children with functional dyspepsia had the longest mean OCTT(110.8±26.7 minutes).There was no significant correlation between abdominal pain severity and OCTT(r=0.18,P=0.35,Spearman correlation coefficient).OCTT did not differ between those exposed to stressful events and those not exposed to such events(P>0.05).CONCLUSION Children with FAPDs have longer OCTT than healthy controls.However,the lack of a significant correlation between OCTT and symptom severity suggests that delayed small intestinal transit alone is not a substantial contributor to FAPD pathophysiology.展开更多
Testing is a standard method for verification of software performance. Producing efficient and appropriate test case is an important aspect in testing. Specification based testing presents a method to derive test dat...Testing is a standard method for verification of software performance. Producing efficient and appropriate test case is an important aspect in testing. Specification based testing presents a method to derive test data from software specification. Because of the precision and concision of specification, the test data derived from specification can test the software efficiently and entirely. This paper demonstrates a test class framework(TCF) on a file reading case study, specified using Z notation. This test class framework defines test case sets, providing structure to the testing process. Flexibility is preserved so that many testing strategies can be used.展开更多
This paper presents modified version of a realistic test tool suitable to Design For Testability （DFT） and Built-ln Self Test （BIST） environments. A comprehensive tool is developed in the form of a test simulator....This paper presents modified version of a realistic test tool suitable to Design For Testability （DFT） and Built-ln Self Test （BIST） environments. A comprehensive tool is developed in the form of a test simulator. The simulator is capable of providing a required goal of test for the Circuit Under Test （CUT）. The simulator uses the approach of fault diagnostics with fault grading procedures to provide the optimum tests. The current version of the simulator embeds features of exhaustive and pseudo-random test generation schemes along with the search solutions of cost effective test goals. The simulator provides facilities of realizing all possible pseudo-random sequence generators with all possible combinations of seeds. The tool is developed on a common Personal Computer （PC） platform and hence no special software is required. Thereby, it is a low cost tool hence economical. The tool is very much suitable for determining realistic test sequences for a targeted goal of testing for any CUT. The developed tool incorporates flexible Graphical User Interface （GUI） procedures and can be operated without any special programming skill. The tool is debugged and tested with the results of many bench mark circuits. Further, this developed tool can be utilized for educational purposes for many courses such as fault-tolerant computing, fault diagnosis, digital electronics, and safe-reliable-testable digital logic designs.展开更多
The China Spallation Neutron Source(CSNS)is the fourth pulsed accelerator-driven neutron source in the world,and it achieved its design target of 100 kW in 2020.The planned China Spallation Neutron Source Phase II(CSN...The China Spallation Neutron Source(CSNS)is the fourth pulsed accelerator-driven neutron source in the world,and it achieved its design target of 100 kW in 2020.The planned China Spallation Neutron Source Phase II(CSNS-II)commenced in 2024.The CSNS-II linac design primarily involves the addition of a radio-frequency ion source and a section of a superconducting linear accelerator composed of two types of superconducting cavities,namely double-spoke and six-cell elliptical cavities,after the drift tube linac(DTL).The development of the double-spoke superconducting cavity began in early 2021,and by January 2023,the welding,post-processing,and vertical tests of two 324 MHz double-spoke cavity prototypes were completed,with vertical test gradients of 11.6 and 15 MV/m,and Q_(0)≥3×10^(10)@E_(acc)≤10 MV/m.The R&D of the cryomodule began in January 2022.In October 2023,the clean assembly of the double-spoke cavity string and cold mass installation of the cryomodule commenced,with the installation of the cryomodule and valve box completing in two months.In January 2024,a horizontal test of the cryomodule was completed,making it the first double-spoke cavity cryomodule in China.The test results showed that the maximum gradients of the two superconducting cavities at a pulse width of 4 ms and repetition frequency of 25 Hz were 12.8 and 15.2 MV/m,respectively.This article provides a detailed introduction to the double-spoke superconducting cavity,tuner,coupler,and cryomodule,elaborates on the clean assembly of the cavity string and cold mass installation of the cryomodule,and provides a detailed analysis of the horizontal test results.展开更多
With the rapid development and commercialization of wireless communications,the execution of OTA testing requires a tremendous amount of test time.Therefore,test time reduction is of great significance.The objective o...With the rapid development and commercialization of wireless communications,the execution of OTA testing requires a tremendous amount of test time.Therefore,test time reduction is of great significance.The objective of this article is to determine optimal measurement grids for SISO OTA testing of 5G Sub-6 GHz user equipments(UEs)in anechoic chamber with satisfactory accuracy and efficiency.The effect of different grid configurations on OTA performance is analyzed quantitatively using reference radiation patterns at different bands.These patterns are utilized to mimic the worst-case radiation patterns of 5G Sub-6 GHz UEs.Subsequently,the associated measurement uncertainty(MU)terms are quantitatively analyzed and determined based on statistical analysis.According to the comparison of calculated MUs,reduction of grid points from currentlyrequired 62(30/30,Δθ/Δϕ)to 26(45/45)could achieve roughly 60%test time reduction for Sub-6 GHz,while still maintaining an uncertainty level of≤0.25 dB.These values can be further reduced to 14(60/60)with 80%reduction for Sub-3 GHz.More importantly,the recommended grid configurations in this research are applicable to both TIS and TRP testing.展开更多
Fault container and shaking table tests are crucial for studying co-seismic dislocation in cross-fault tunnels,with the design and functionality of the container significantly affecting the accuracy of dynamic respons...Fault container and shaking table tests are crucial for studying co-seismic dislocation in cross-fault tunnels,with the design and functionality of the container significantly affecting the accuracy of dynamic response analyses of tunnel linings.This research introduces a fault container developed as part of a significant active fault-crossing tunnel project in the high-intensity seismic zone of western China.The container is designed to simulate both strike-slip and dip-slip fault characteristics with adjustable fault angles.Extensive testing,including shaking table tests under strong seismic conditions,three-dimensional(3D)finite element numerical simulations,and hammer tests,were conducted to evaluate the modal characteristics of the container under various conditions.The study highlights the resonance characteristics of the soil-container system,the signal consistency across different dislocations,and the dynamic response patterns both with and without pulse-like seismic motions and varying intensities.The results indicate that the natural frequencies of the container and the model soil,determined through white noise scanning,are 23.74 Hz and 6.355 Hz,respectively,suggesting no resonance in the model soil-container structure.The dynamic response characteristics of the empty container show good integrity and versatility under various seismic excitations.The consistency of the free-field time history curve confirms that the newly developed fault container effectively simulates the continuity and boundary conditions of the free-field.Time domain analysis conducted before and after fault dislocation demonstrates the capability of the container to accurately replicate the coupling effects of fault and seismic motions.展开更多
The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for ...The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.展开更多
Knowledge of the dynamic modulus of bituminous mixtures is practical and theoretically meaningful in pavement design,construction,and monitoring.The tests in the laboratory for the determination of asphalt concrete(AC...Knowledge of the dynamic modulus of bituminous mixtures is practical and theoretically meaningful in pavement design,construction,and monitoring.The tests in the laboratory for the determination of asphalt concrete(AC)moduli include the resilient modulus through the indirect tensile test(EN 12697-26),the complex modulus through the four point bending beam(EN 12697-26),the asphalt mixture performance tester(AMPT)and the simple performance tester(SPT)(AASHTO T342).Unfortunately,the tests above are time-consuming and quite expensive.On the other hand,the standard ASTM E1876 for resonant tests applies only to very thin(stocky)cylindrical samples(with a thickness-to-radius ratio,t/r,lower than 0.5)while the typical AC samples produced in the laboratory do not satisfy the ASTM E1876 requirements.Consequently,the main objective of this study is to set up and implement a tentative method to extend the range of applicability of the standard ASTM E1876 to common AC samples.The methodology was to carry out resonant tests on slender samples and to cut each of them into stocky samples(these latter complying with ASTM E1876 requirements in terms of t/r),deriving the master curve per material.These master curves allowed for deriving the value of the dynamic modulus for the given selected sample under its particular test conditions during the resonant test(i.e.,temperature and frequency).Consequently,simplified formulae were provided for AC samples.Results were compared to Witczak's estimates.These formulae provide an approximate tool to carry out low-cost and high-speed inferences at the laboratory stage on common AC samples,whatever their thickness is.Additional studies are needed to investigate the reliability of the method further and reduce uncertainties.展开更多
The lack of systematic and scientific top-level arrangement in the field of civil aircraft flight test leads to the problems of long duration and high cost.Based on the flight test activity,mathematical models of flig...The lack of systematic and scientific top-level arrangement in the field of civil aircraft flight test leads to the problems of long duration and high cost.Based on the flight test activity,mathematical models of flight test duration and cost are established to set up the framework of flight test process.The top-level arrangement for flight test is optimized by multi-objective algorithm to reduce the duration and cost of flight test.In order to verify the necessity and validity of the mathematical models and the optimization algorithm of top-level arrangement,real flight test data is used to make an example calculation.Results show that the multi-objective optimization results of the top-level flight arrangement are better than the initial arrangement data,which can shorten the duration,reduce the cost,and improve the efficiency of flight test.展开更多
Considering the challenges posed by external disturbances on carrier-based aircraft land-ing control,higher demands are required for the precision and convergence of the carrier landingcontrol system.First,this paper ...Considering the challenges posed by external disturbances on carrier-based aircraft land-ing control,higher demands are required for the precision and convergence of the carrier landingcontrol system.First,this paper proposes an Adaptive Terminal Sliding Combined Super TwistingControl(ATS-STC)method to address the issues of low precision,slow convergence,and poor dis-turbance rejection capability resulting from external disturbances,such as carrier air-wake and deckmotion.By introducing a nonlinear term into the sliding surface and employing an integralapproach,the proposed ATS-STC method can ensure finite-time convergence and mitigate the chat-tering problem.An adaptive law is also utilized to estimate the external disturbances,therebyenhancing the anti-disturbance performance.Then,the stability and convergence time analysis ofthe designed controller are conducted.Based on the proposed method,an Automatic Carrier Land-ing System(ACLS)is developed to perform the carrier landing control task.Furthermore,a multi-dimensional validation is carried out.For the numerical simulation test,the Terminal Sliding ModeControl(TSMC)method and Proportion Integration Differentiation(PID)method are introducedas comparison,the quantitative assessment results show that the tracking error of TSMC and PIDcan reach 1.5 times and 2 times that of the proposed method.Finally,the Hardware-in-the-Loop(HIL)test and real flight test are conducted.All the experimental results demonstrate that the pro-posed control method is more effective and precise.展开更多
In high-risk industrial environments like nuclear power plants,precise defect identification and localization are essential for maintaining production stability and safety.However,the complexity of such a harsh enviro...In high-risk industrial environments like nuclear power plants,precise defect identification and localization are essential for maintaining production stability and safety.However,the complexity of such a harsh environment leads to significant variations in the shape and size of the defects.To address this challenge,we propose the multivariate time series segmentation network(MSSN),which adopts a multiscale convolutional network with multi-stage and depth-separable convolutions for efficient feature extraction through variable-length templates.To tackle the classification difficulty caused by structural signal variance,MSSN employs logarithmic normalization to adjust instance distributions.Furthermore,it integrates classification with smoothing loss functions to accurately identify defect segments amid similar structural and defect signal subsequences.Our algorithm evaluated on both the Mackey-Glass dataset and industrial dataset achieves over 95%localization and demonstrates the capture capability on the synthetic dataset.In a nuclear plant's heat transfer tube dataset,it captures 90%of defect instances with75%middle localization F1 score.展开更多
The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo ext...The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo extensive in-house tests and prolonged field tests for certification and approval before operational deployment,leading to high costs,delays,and operational disruptions.This paper introduces a GNSS-based train control localization framework which eliminates the need for on-site testing by leveraging train movement dynamics and 3D environment modeling to create a zero on-site testing platform.The proposed framework simulates train movement and the surrounding 3D environment using collected railway line location data and environmental attributes to generate realistic multipath signals and obscuration effects.This approach enables comprehensive laboratory-based case studies for train localization,reducing the huge amount test of needed for physical field trials.The framework is established in house,using the data collected at the Test Base of China Academy of Railway Sciences(Circular Railway).Results from the open area and cutting environment tests demonstrate high localization accuracy repeatability within the simulated environment,validating the feasibility and effectiveness of zero on-site testing for GNSS-based train control systems.This research highlights the potential of GNSS simulation platforms in enhancing cost efficiency,operational safety,and accuracy for future digital railways.展开更多
In the current social environment,the importance of energy conservation and emission reduction is increasing day by day for both the country and its people.Electronic and electrical products,as important items for peo...In the current social environment,the importance of energy conservation and emission reduction is increasing day by day for both the country and its people.Electronic and electrical products,as important items for people’s production and life,require high attention from industry insiders in terms of their energy efficiency testing.Relying on energy efficiency testing can achieve the goal of energy conservation and emission reduction,and related quality control technologies will also inject new momentum into the green development of the industry.This article will discuss the practical strategies of quality control technology for energy efficiency testing of electronic and electrical products based on the significance of such testing,hoping to provide some help.展开更多
文摘It is challenging to diagnose isolated hyperbilirubinemia with rare and complex etiologies under the constraints of traditional testing conditions.Herein,we present a rare case of coexisting Gilbert syndrome(GS)and erythropoietic protoporphyria(EPP),which has not been previously documented.CASE SUMMARY We present a rare case of coexisting GS and EPP in a 23-year-old Chinese male with a long history of jaundice and recently found splenomegaly.Serial nonspecific hemolysis screening tests yielded inconsistent results,and investigations for common hemolytic etiologies were negative.However,Levitt’s carbon monoxide breath test,which measures erythrocyte lifespan(the gold-standard marker of hemolysis),demonstrated significant hemolysis,revealing a markedly shortened erythrocyte lifespan of 11 days(normal average 120 days).Genetic testing subsequently confirmed EPP with a homozygous ferrochelatase gene mutation and GS with a heterozygous uridine diphosphate glucuronosyl trans-ferase 1A1 gene mutation.CONCLUSION The rapid,non-invasive Levitt’s carbon monoxide breath test resolved the diagnostic challenge posed by a rare and complex cause of hyperbilirubinemia.
文摘BACKGROUND Small intestinal bacterial overgrowth(SIBO)is suspected and excluded frequently in functional gastrointestinal(GI)disorders.Children presenting with various esophago-gastro-duodenal(upper GI)symptoms are rarely subjected to investig-ations for SIBO.AIM To estimate the frequency of SIBO in children having functional upper GI sym-ptoms(as cases)and to compare the result of the SIBO status to that of the con-trols.METHODS Children aged 6 to 18 who presented with upper GI symptoms were selected for the study.All children were subjected to upper GI endoscopy before being advised of any proton pump inhibitors(PPIs).Children with normal endoscopy were assigned as cases,and children having any endoscopic lesion were design-ated as controls.Both groups were subjected to a glucose-hydrogen breath test by Bedfont Gastrolyser.RESULTS A total of 129 consecutive children who were naive to PPIs and had normal ba-seline investigations were included in the study.Among them,67 patients had endoscopic lesions and served as the control group,with six cases being excluded due to the presence of Helicobacter pylori in gastric biopsies.Sixty-two children with normal endoscopy results formed the case group.In the case group,35 children(59%)tested positive for hydrogen breath tests,compared to 13 children(21%)in the control group.The calculated odds ratio was 5.38(95%confidence interval:2.41-12.0),which was statistically significant.Further analysis of symptoms revealed that nausea,halitosis,foul-smelling eructation,and epigastric fullness were positive predictors of SIBO.CONCLUSION It is worthwhile to investigate and treat SIBO in all children presenting with upper GI symptoms that are not explained by endoscopy findings.
基金support of this project through the Southwest Regional Partnership on Carbon Sequestration(Grant No.DE-FC26-05NT42591)Improving Production in the Emerging Paradox Oil Play(Grant No.DE-FE0031775).
文摘Geomechanical properties of rocks vary across different measurement scales,primarily due to heterogeneity.Micro-scale geomechanical tests,including micro-scale“scratch tests”and nano-scale nanoindentation tests,are attractive at different scales.Each method requires minimal sample volume,is low cost,and includes a relatively rapid measurement turnaround time.However,recent micro-scale test results–including scratch test results and nanoindentation results–exhibit tangible variance and uncertainty,suggesting a need to correlate mineral composition mapping to elastic modulus mapping to isolate the relative impact of specific minerals.Different research labs often utilize different interpretation methods,and it is clear that future micro-mechanical tests may benefit from standardized testing and interpretation procedures.The objectives of this study are to seek options for standardized testing and interpretation procedures,through two specific objectives:(1)Quantify chemical and physical controls on micro-mechanical properties and(2)Quantify the source of uncertainties associated with nanoindentation measurements.To reach these goals,we conducted mechanical tests on three different scales:triaxial compression tests,scratch tests,and nanoindentation tests.We found that mineral phase weight percentage is highly correlated with nanoindentation elastic modulus distribution.Finally,we conclude that nanoindentation testing is a mineralogy and microstructure-based method and generally yields significant uncertainty and overestimation.The uncertainty of the testing method is largely associated with not mapping pore space a priori.Lastly,the uncertainty can be reduced by combining phase mapping and modulus mapping with substantial and random data sampling.
文摘This study presents the results of a Monte Carlo simulation to compare the statistical power of Siegel-Tukey and Savage tests.The main purpose of the study is to evaluate the statistical power of both tests in scenarios involving Normal,Platykurtic and Skewed distributions over different sample sizes and standard deviation values.In the study,standard deviation ratios were set as 2,3,4,1/2,1/3 and 1/4 and power comparisons were made between small and large sample sizes.For equal sample sizes,small sample sizes of 5,8,10,12,16 and 20 and large sample sizes of 25,50,75 and 100 were used.For different sample sizes,the combinations of(4,16),(8,16),(10,20),(16,4),(16,8)and(20,10)small sample sizes and(10,30),(30,10),(50,75),(50,100),(75,50),(75,100),(100,50)and(100,75)large sample sizes were examined in detail.According to the findings,the power analysis under variance heterogeneity conditions shows that the Siegel-Tukey test has a higher statistical power than the other nonparametric Savage test at small and large sample sizes.In particular,the Siegel-Tukey test was reported to offer higher precision and power under variance heterogeneity,regardless of having equal or different sample sizes.
文摘In recent years,the application scenarios of electrical and electronic products have become increasingly diverse worldwide.The impact of climatic environmental tests on the performance of related products has attracted much attention,and formulating scientific and reasonable environmental test plans has become an important step to ensure product quality and reliability.
文摘BACKGROUND Human immunodeficiency virus(HIV)recency testing provides data that can be used to monitor the trend of new HIV infections.The effectiveness of using people identified with recent infection to identify partners with new HIV infection through partner notification services(PNS)is not well documented.AIM To determine the pooled prevalence of recency testing coverage,recent infection,reclassification(recent to longterm infection)and PNS cascade among newly diagnosed people living with HIV.METHODS PubMed,Cochrane Library and Embase were searched for articles published between January 2018 and November 2024.Studies were included if they reported recency coverage and/or PNS among people newly diagnosed with HIV and used recent infection testing algorithm(RITA).Recency coverage was defined as proportion of people tested using rapid testing for recent infection(RTRI)among those newly diagnosed with HIV.RITA further classifies RTRI results using viral load results(≥1000 copies/mL vs<1000 copies/mL)to confirm recency status.For studies with PNS,we evaluated the cascade:Number of partners elicited,successfully contacted,eligible for HIV testing,tested and HIV diagnosis.PNS effectiveness was measured by proportion of new HIV diagnoses from tested partners.Using random effects models,we computed the pooled estimate of recency outcomes and 95%confidence intervals(CIs).RESULTS Twenty-five studies from 17-low-and middle-income countries were included.Of 276315 newly diagnosed people living with HIV,79864 underwent RTRI with an overall pooled recency coverage of 87%(95%CI:67-96).The pooled prevalence of RTRI and RITA recency were 12%(95%CI:9-16)and 7%(95%CI:4-10),respectively.Pooled prevalence of RTRI reclassification was 34%(95%CI:22-49).Of the recent cases who agreed to PNS,253 partners were elicited with an estimated elicitation ratio of 1:1.6.Among partners elicited,99%were successfully contacted,75%were eligible for testing,68%tested for HIV,and 15%were diagnosed with HIV.CONCLUSION High recency testing coverage among newly diagnosed individuals demonstrates the feasibility of monitoring new HIV infections in LMIC.While PNS yielded moderate HIV diagnoses,its targeted approach remains a critical strategy for identifying undiagnosed cases.
基金Supported by The University of Kelaniya,No.RP/03/04/13/01/01.
文摘BACKGROUND Functional abdominal pain disorders(FAPDs)are common gut–brain interaction disorders with unclear pathophysiology.While impaired gastrointestinal motility is thought to play a key role,small intestinal dysmotility remains largely unexplored.Orocecal transit time(OCTT),an indirect indicator of small intestinal transit,offers an insight into its potential contribution to FAPD's pathophysiology.AIM To assess OCTT in children with FAPDs compared with healthy children using the lactulose breath hydrogen test.METHODS Thirty-four children(44.1%males,age 5–12 years,mean 7.2±2.4 years)with FAPDs attending North Colombo Teaching Hospital,Ragama,Sri Lanka,were included in the analysis.FAPDs were diagnosed using the Rome IV criteria.None had clinical or laboratory evidence of organic diseases.They were compared with 19 healthy controls(47.1%males,age 5-12 years,mean 7.8±2.7 years)from the same geographical area.OCTT was calculated after an 8-hour fast using a previously validated technique.Breath hydrogen levels were measured at baseline and 15-minute intervals for 180 minutes post-lactulose ingestion(10 g in 10%solution).At each time point,3 breath samples were collected and analyzed.OCTT was quantified as the time taken to achieve a sustained breath hydrogen increase>10 parts per million above baseline.Symptoms were recorded using the Rome IV questionnaire,and symptom severity was graded on a 0-4 Likert scale.RESULTS Patients with FAPDs had increased OCTT(median,90 minutes;interquartile range,75-120 minutes)compared to controls(median,75 minutes;interquartile range,60-75 minutes)(P=0.0045,Mann-Whitney U-test).Children with functional dyspepsia had the longest mean OCTT(110.8±26.7 minutes).There was no significant correlation between abdominal pain severity and OCTT(r=0.18,P=0.35,Spearman correlation coefficient).OCTT did not differ between those exposed to stressful events and those not exposed to such events(P>0.05).CONCLUSION Children with FAPDs have longer OCTT than healthy controls.However,the lack of a significant correlation between OCTT and symptom severity suggests that delayed small intestinal transit alone is not a substantial contributor to FAPD pathophysiology.
文摘Testing is a standard method for verification of software performance. Producing efficient and appropriate test case is an important aspect in testing. Specification based testing presents a method to derive test data from software specification. Because of the precision and concision of specification, the test data derived from specification can test the software efficiently and entirely. This paper demonstrates a test class framework(TCF) on a file reading case study, specified using Z notation. This test class framework defines test case sets, providing structure to the testing process. Flexibility is preserved so that many testing strategies can be used.
文摘This paper presents modified version of a realistic test tool suitable to Design For Testability （DFT） and Built-ln Self Test （BIST） environments. A comprehensive tool is developed in the form of a test simulator. The simulator is capable of providing a required goal of test for the Circuit Under Test （CUT）. The simulator uses the approach of fault diagnostics with fault grading procedures to provide the optimum tests. The current version of the simulator embeds features of exhaustive and pseudo-random test generation schemes along with the search solutions of cost effective test goals. The simulator provides facilities of realizing all possible pseudo-random sequence generators with all possible combinations of seeds. The tool is developed on a common Personal Computer （PC） platform and hence no special software is required. Thereby, it is a low cost tool hence economical. The tool is very much suitable for determining realistic test sequences for a targeted goal of testing for any CUT. The developed tool incorporates flexible Graphical User Interface （GUI） procedures and can be operated without any special programming skill. The tool is debugged and tested with the results of many bench mark circuits. Further, this developed tool can be utilized for educational purposes for many courses such as fault-tolerant computing, fault diagnosis, digital electronics, and safe-reliable-testable digital logic designs.
文摘The China Spallation Neutron Source(CSNS)is the fourth pulsed accelerator-driven neutron source in the world,and it achieved its design target of 100 kW in 2020.The planned China Spallation Neutron Source Phase II(CSNS-II)commenced in 2024.The CSNS-II linac design primarily involves the addition of a radio-frequency ion source and a section of a superconducting linear accelerator composed of two types of superconducting cavities,namely double-spoke and six-cell elliptical cavities,after the drift tube linac(DTL).The development of the double-spoke superconducting cavity began in early 2021,and by January 2023,the welding,post-processing,and vertical tests of two 324 MHz double-spoke cavity prototypes were completed,with vertical test gradients of 11.6 and 15 MV/m,and Q_(0)≥3×10^(10)@E_(acc)≤10 MV/m.The R&D of the cryomodule began in January 2022.In October 2023,the clean assembly of the double-spoke cavity string and cold mass installation of the cryomodule commenced,with the installation of the cryomodule and valve box completing in two months.In January 2024,a horizontal test of the cryomodule was completed,making it the first double-spoke cavity cryomodule in China.The test results showed that the maximum gradients of the two superconducting cavities at a pulse width of 4 ms and repetition frequency of 25 Hz were 12.8 and 15.2 MV/m,respectively.This article provides a detailed introduction to the double-spoke superconducting cavity,tuner,coupler,and cryomodule,elaborates on the clean assembly of the cavity string and cold mass installation of the cryomodule,and provides a detailed analysis of the horizontal test results.
基金supported by the Beijing Natural Science Foundation under Grant L253002.
文摘With the rapid development and commercialization of wireless communications,the execution of OTA testing requires a tremendous amount of test time.Therefore,test time reduction is of great significance.The objective of this article is to determine optimal measurement grids for SISO OTA testing of 5G Sub-6 GHz user equipments(UEs)in anechoic chamber with satisfactory accuracy and efficiency.The effect of different grid configurations on OTA performance is analyzed quantitatively using reference radiation patterns at different bands.These patterns are utilized to mimic the worst-case radiation patterns of 5G Sub-6 GHz UEs.Subsequently,the associated measurement uncertainty(MU)terms are quantitatively analyzed and determined based on statistical analysis.According to the comparison of calculated MUs,reduction of grid points from currentlyrequired 62(30/30,Δθ/Δϕ)to 26(45/45)could achieve roughly 60%test time reduction for Sub-6 GHz,while still maintaining an uncertainty level of≤0.25 dB.These values can be further reduced to 14(60/60)with 80%reduction for Sub-3 GHz.More importantly,the recommended grid configurations in this research are applicable to both TIS and TRP testing.
基金supported by the National Natural Science Foundation of China(Grant Nos.52108361 and 41977252)the Sichuan Science and Technology Program of China(Grant Nos.2024ZYD0154 and 2024NSFSC0159)the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project(Grant Nos.SKLGP2022Z015 and SKLGP2020Z001).
文摘Fault container and shaking table tests are crucial for studying co-seismic dislocation in cross-fault tunnels,with the design and functionality of the container significantly affecting the accuracy of dynamic response analyses of tunnel linings.This research introduces a fault container developed as part of a significant active fault-crossing tunnel project in the high-intensity seismic zone of western China.The container is designed to simulate both strike-slip and dip-slip fault characteristics with adjustable fault angles.Extensive testing,including shaking table tests under strong seismic conditions,three-dimensional(3D)finite element numerical simulations,and hammer tests,were conducted to evaluate the modal characteristics of the container under various conditions.The study highlights the resonance characteristics of the soil-container system,the signal consistency across different dislocations,and the dynamic response patterns both with and without pulse-like seismic motions and varying intensities.The results indicate that the natural frequencies of the container and the model soil,determined through white noise scanning,are 23.74 Hz and 6.355 Hz,respectively,suggesting no resonance in the model soil-container structure.The dynamic response characteristics of the empty container show good integrity and versatility under various seismic excitations.The consistency of the free-field time history curve confirms that the newly developed fault container effectively simulates the continuity and boundary conditions of the free-field.Time domain analysis conducted before and after fault dislocation demonstrates the capability of the container to accurately replicate the coupling effects of fault and seismic motions.
基金support of Natural Science Foundation of China(Grant No.52108324,No.52008207,and No.52108298)for conducting this study.
文摘The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.
文摘Knowledge of the dynamic modulus of bituminous mixtures is practical and theoretically meaningful in pavement design,construction,and monitoring.The tests in the laboratory for the determination of asphalt concrete(AC)moduli include the resilient modulus through the indirect tensile test(EN 12697-26),the complex modulus through the four point bending beam(EN 12697-26),the asphalt mixture performance tester(AMPT)and the simple performance tester(SPT)(AASHTO T342).Unfortunately,the tests above are time-consuming and quite expensive.On the other hand,the standard ASTM E1876 for resonant tests applies only to very thin(stocky)cylindrical samples(with a thickness-to-radius ratio,t/r,lower than 0.5)while the typical AC samples produced in the laboratory do not satisfy the ASTM E1876 requirements.Consequently,the main objective of this study is to set up and implement a tentative method to extend the range of applicability of the standard ASTM E1876 to common AC samples.The methodology was to carry out resonant tests on slender samples and to cut each of them into stocky samples(these latter complying with ASTM E1876 requirements in terms of t/r),deriving the master curve per material.These master curves allowed for deriving the value of the dynamic modulus for the given selected sample under its particular test conditions during the resonant test(i.e.,temperature and frequency).Consequently,simplified formulae were provided for AC samples.Results were compared to Witczak's estimates.These formulae provide an approximate tool to carry out low-cost and high-speed inferences at the laboratory stage on common AC samples,whatever their thickness is.Additional studies are needed to investigate the reliability of the method further and reduce uncertainties.
基金supported by the National Natural Science Foundation of China(62073267,61903305)the Fundamental Research Funds for the Central Universities(HXGJXM202214).
文摘The lack of systematic and scientific top-level arrangement in the field of civil aircraft flight test leads to the problems of long duration and high cost.Based on the flight test activity,mathematical models of flight test duration and cost are established to set up the framework of flight test process.The top-level arrangement for flight test is optimized by multi-objective algorithm to reduce the duration and cost of flight test.In order to verify the necessity and validity of the mathematical models and the optimization algorithm of top-level arrangement,real flight test data is used to make an example calculation.Results show that the multi-objective optimization results of the top-level flight arrangement are better than the initial arrangement data,which can shorten the duration,reduce the cost,and improve the efficiency of flight test.
基金supported by the National Natural Science Foundation of China(No.T2288101)the National Key Research and Development Project,China(No.2020YFC1512500)the Academic Excellence Foundation of Beijing University of Aeronautics and Astronautics(BUAA)。
文摘Considering the challenges posed by external disturbances on carrier-based aircraft land-ing control,higher demands are required for the precision and convergence of the carrier landingcontrol system.First,this paper proposes an Adaptive Terminal Sliding Combined Super TwistingControl(ATS-STC)method to address the issues of low precision,slow convergence,and poor dis-turbance rejection capability resulting from external disturbances,such as carrier air-wake and deckmotion.By introducing a nonlinear term into the sliding surface and employing an integralapproach,the proposed ATS-STC method can ensure finite-time convergence and mitigate the chat-tering problem.An adaptive law is also utilized to estimate the external disturbances,therebyenhancing the anti-disturbance performance.Then,the stability and convergence time analysis ofthe designed controller are conducted.Based on the proposed method,an Automatic Carrier Land-ing System(ACLS)is developed to perform the carrier landing control task.Furthermore,a multi-dimensional validation is carried out.For the numerical simulation test,the Terminal Sliding ModeControl(TSMC)method and Proportion Integration Differentiation(PID)method are introducedas comparison,the quantitative assessment results show that the tracking error of TSMC and PIDcan reach 1.5 times and 2 times that of the proposed method.Finally,the Hardware-in-the-Loop(HIL)test and real flight test are conducted.All the experimental results demonstrate that the pro-posed control method is more effective and precise.
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(2024ZD0608100)the National Natural Science Foundation of China(62332017,U22A2022)
文摘In high-risk industrial environments like nuclear power plants,precise defect identification and localization are essential for maintaining production stability and safety.However,the complexity of such a harsh environment leads to significant variations in the shape and size of the defects.To address this challenge,we propose the multivariate time series segmentation network(MSSN),which adopts a multiscale convolutional network with multi-stage and depth-separable convolutions for efficient feature extraction through variable-length templates.To tackle the classification difficulty caused by structural signal variance,MSSN employs logarithmic normalization to adjust instance distributions.Furthermore,it integrates classification with smoothing loss functions to accurately identify defect segments amid similar structural and defect signal subsequences.Our algorithm evaluated on both the Mackey-Glass dataset and industrial dataset achieves over 95%localization and demonstrates the capture capability on the synthetic dataset.In a nuclear plant's heat transfer tube dataset,it captures 90%of defect instances with75%middle localization F1 score.
基金supported by the National Natural Science Foundation of China(62027809,U2268206,T2222015,U2468202).
文摘The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo extensive in-house tests and prolonged field tests for certification and approval before operational deployment,leading to high costs,delays,and operational disruptions.This paper introduces a GNSS-based train control localization framework which eliminates the need for on-site testing by leveraging train movement dynamics and 3D environment modeling to create a zero on-site testing platform.The proposed framework simulates train movement and the surrounding 3D environment using collected railway line location data and environmental attributes to generate realistic multipath signals and obscuration effects.This approach enables comprehensive laboratory-based case studies for train localization,reducing the huge amount test of needed for physical field trials.The framework is established in house,using the data collected at the Test Base of China Academy of Railway Sciences(Circular Railway).Results from the open area and cutting environment tests demonstrate high localization accuracy repeatability within the simulated environment,validating the feasibility and effectiveness of zero on-site testing for GNSS-based train control systems.This research highlights the potential of GNSS simulation platforms in enhancing cost efficiency,operational safety,and accuracy for future digital railways.
文摘In the current social environment,the importance of energy conservation and emission reduction is increasing day by day for both the country and its people.Electronic and electrical products,as important items for people’s production and life,require high attention from industry insiders in terms of their energy efficiency testing.Relying on energy efficiency testing can achieve the goal of energy conservation and emission reduction,and related quality control technologies will also inject new momentum into the green development of the industry.This article will discuss the practical strategies of quality control technology for energy efficiency testing of electronic and electrical products based on the significance of such testing,hoping to provide some help.
