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Cure Rate Analysis Of National Health Insurance Scheme Claims Payment Survival Times In Ghana: The Case Of Pru District, Ahmed Tamimu, Suleman Nasiru, Dioggban Jakperik Nov 2024

Cure Rate Analysis Of National Health Insurance Scheme Claims Payment Survival Times In Ghana: The Case Of Pru District, Ahmed Tamimu, Suleman Nasiru, Dioggban Jakperik

Al-Bahir

In this study, cure models have been applied to model National Health Insurance Scheme (NHIS) claims payment data with cured proportion using Pru District in the Bono East Region of Ghana as a case study. The covariates effects were also modelled to investigate the effects of the covariates on the cured proportion. The estimates of the parameters of the models were obtained by directly maximizing the observed likelihood functions. Most estimates of the parameters of the cure models are significant at 5% significance level. The study revealed that the cured claims payments rate increases over time with an estimated cured …


The Wallet And The Gut: Forecasting The 2024 Presidential Election With A State-By-State Adaptation Of The Time-For-Change Model, Simeon A. Betapudi, Hadassah Betapudi Nov 2024

The Wallet And The Gut: Forecasting The 2024 Presidential Election With A State-By-State Adaptation Of The Time-For-Change Model, Simeon A. Betapudi, Hadassah Betapudi

Science University Research Symposium (SURS)

This study adapts Abramowitz's Time-for-Change model to a state-level framework to forecast the 2024 U.S. presidential election. The Time-for-Change model’s focus on the popular vote has become less relevant in recent years, given the growing divergence between popular vote outcomes and electoral college results. Our model addresses these issues by adapting the original Time-for-Change predictors (presidential approval rating, GDP, and time in office) to the state level. Using data from five election cycles (2004–2020), we employ an Ordinary Least Squares (OLS) regression to predict incumbent two-party vote share. Unlike the original model, state-level GDP and incumbency duration were found to …


Peptide Receptor Radionuclide Therapy And Clinical Associations With Renal And Hematological Toxicities And Survival In Patients With Neuroendocrine Tumors: An Analysis From Two U.S. Medical Centers, Tao Xu, Joseph S. Dillon, Mary A. Maluccio, Dawn E. Quelle, Sarah H. Nash, Hyunkeun Cho, Kristen E. Limbach, Nicholas J. Skill, Yvette Bren-Mattison, Michael A. O’Rorke Nov 2024

Peptide Receptor Radionuclide Therapy And Clinical Associations With Renal And Hematological Toxicities And Survival In Patients With Neuroendocrine Tumors: An Analysis From Two U.S. Medical Centers, Tao Xu, Joseph S. Dillon, Mary A. Maluccio, Dawn E. Quelle, Sarah H. Nash, Hyunkeun Cho, Kristen E. Limbach, Nicholas J. Skill, Yvette Bren-Mattison, Michael A. O’Rorke

School of Medicine Faculty Publications

Purpose: Renal and hematological toxicity are side effects and dose-limiting factors of Peptide Receptor Radionuclide Therapy (PRRT). We aimed to assess the changes in renal and hematological function and associations with survival in neuroendocrine tumor (NET) patients treated with PRRT. Methods: A retrospective cohort of 448 NET patients treated with either 177Lu-DOTATATE or 90Y-DOTATOC were followed for changes of renal and hematological function. Renal function was assessed by monitoring changes in serum creatinine, blood urea nitrogen and estimated glomerular filtration rate. Hematological function was determined by examining changes in white blood cell counts (WBC), platelet counts, and hemoglobin levels over …


Using Causal Diagrams Within The Grading Of Recommendations, Assessment, Development And Evaluation Framework To Evaluate Confounding Adjustment In Observational Studies, Kevin Mcintyre, Karina N Tassiopoulos, Curtis Jeffrey, Saverio Stranges, Janet Martin Nov 2024

Using Causal Diagrams Within The Grading Of Recommendations, Assessment, Development And Evaluation Framework To Evaluate Confounding Adjustment In Observational Studies, Kevin Mcintyre, Karina N Tassiopoulos, Curtis Jeffrey, Saverio Stranges, Janet Martin

Epidemiology and Biostatistics Publications

BACKGROUND AND OBJECTIVES: The current Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system instructs appraisers to evaluate whether individual observational studies have sufficiently adjusted for confounding. However, it does not provide an explicit, transparent, or reproducible method for doing so. This article explores how implementing causal graphs into the GRADE framework can help appraisers and end-users of GRADE products to evaluate the adequacy of confounding control from observational studies.

METHODS: Using modern epidemiological theory, we propose a system for incorporating causal diagrams into the GRADE process to assess confounding control.

RESULTS: Integrating causal graphs into the GRADE framework enables …


Cane Toad, Department Of Primary Industries And Regional Development, Western Australia Nov 2024

Cane Toad, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

This factsheet provides information about the identification, biology, impact, and management of the cane toad.

The cane toad (Rhinella marina), or giant toad, is native to central and South America. It has been introduced to many countries, including northern and eastern Australia. The cane toad is a declared pest under the Biosecurity and Agriculture Management Act 2007 (BAM Act) in Western Australia (WA). The Western Australian Organism List (WAOL), available on the website at dpird.wa.gov.au) contains information on the area(s) in which this pest is declared, and the control and keeping categories to which it has been assigned in WA.


A Complete Invariant For Shift Equivalence For Boolean Matrices And Finite Relations, Ethan Akin, Marian Mrozek, Mateusz Przybylski, Jim Wiseman Nov 2024

A Complete Invariant For Shift Equivalence For Boolean Matrices And Finite Relations, Ethan Akin, Marian Mrozek, Mateusz Przybylski, Jim Wiseman

Mathematics and Statistics Faculty Research & Creative Works

We give a complete invariant for shift equivalence for Boolean matrices (equivalently finite relations), in terms of the period, the induced partial order on recurrent components, and the cohomology class of the relation on those components.


Adverse Childhood Experiences And Hiv-Related Stigma: A Quantitative Survey Of Tanzanian Men, June 2019, Amandeep Kaur, Monique J. Brown Ph.D., Mph, Geoffrey K. Kangogo, Xiaoming Li Ph.D., Ivan E. Teri, Gaspar Mbita, Aima A. Ahonkhai, Donaldson F. Conserve Nov 2024

Adverse Childhood Experiences And Hiv-Related Stigma: A Quantitative Survey Of Tanzanian Men, June 2019, Amandeep Kaur, Monique J. Brown Ph.D., Mph, Geoffrey K. Kangogo, Xiaoming Li Ph.D., Ivan E. Teri, Gaspar Mbita, Aima A. Ahonkhai, Donaldson F. Conserve

Faculty Publications

Experiencing adverse childhood experiences (ACEs) may impact personal opinions, attitudes, and judgments, which can further result in HIV-related stigma. HIV-related stigma consequentially may impact HIV preventive measures such as HIV testing, pre-exposure prophylaxis uptake, and condom use. The extent to which ACEs influence HIV-related stigma perception has not been well studied. Therefore, the study aimed to examine the association between ACEs and perceived and interpersonal HIV-related stigma among Tanzanian HIV-negative men. Quantitative survey data were obtained from the Tanzania STEP (Self-Testing Education and Promotion) project established in four wards: Mabibo, Manzese, Tandale, and Mwanyanamala. A total of 507 men responded …


Optimal Har Inference, Liyu Dou Nov 2024

Optimal Har Inference, Liyu Dou

Research Collection School Of Economics

This paper addresses the problem of deriving heteroskedasticity and autocorrelation robust (HAR) inference for a scalar parameter of interest, under the assumption of a known upper bound on data persistence. Finite-sample optimal tests are derived within the Gaussian location model, revealing that robustness-efficiency tradeoffs are primarily determined by the maximal persistence. With a suitable adjustment to the critical value, the equal-weighted cosine (EWC) test emerges as nearly optimal, wherein the long-run variance is estimated through projections onto q type II cosines. This approach establishes a direct link between the choice of q and persistence assumptions, accompanied by adjustments to the …


Learning Problems Related To Stochastic Differential Equations, Jinpu Zhou Nov 2024

Learning Problems Related To Stochastic Differential Equations, Jinpu Zhou

LSU Doctoral Dissertations

Stochastic differential equations (SDEs) are essential for modeling systems influenced by both deterministic dynamics and random fluctuations, with applications in a wide variety of disciplines. This thesis develops a Bayesian framework for nonparametric learning in SDEs, addressing key challenges in inference, particularly when dealing with complex systems and incomplete data. The thesis begins by establishing a theoretical foundation in optimization over Hilbert spaces, including a generalized representer theorem to address infinite-dimensional optimization problems encountered in nonparametric inference. Building on this, we introduce a Bayesian framework with shrinkage priors to learn drift functions from high-frequency data. Bayesian approach incorporates low-cost sparse …


Evaluation And Lessons Learned From The Dissemination And Implementation Science Scholars Program In The National Cancer Prevention And Control Research Network, Daniela B. Friedman, Cam Escoffery, Elaine H. Morrato, Cynthia A. Thomson, Courtney N. Petagna, Freda Allyson Hucek, Mary Wangen, Aubrey Villalobos, James R. Hébert Scd, Samuel Noblet, Mayank Sakhuja, David O. Garcia, Jennifer L. Cruz, Stephanie B. Wheeler Oct 2024

Evaluation And Lessons Learned From The Dissemination And Implementation Science Scholars Program In The National Cancer Prevention And Control Research Network, Daniela B. Friedman, Cam Escoffery, Elaine H. Morrato, Cynthia A. Thomson, Courtney N. Petagna, Freda Allyson Hucek, Mary Wangen, Aubrey Villalobos, James R. Hébert Scd, Samuel Noblet, Mayank Sakhuja, David O. Garcia, Jennifer L. Cruz, Stephanie B. Wheeler

Faculty Publications

Background:

The Centers for Disease Control and Prevention (CDC)-funded Cancer Prevention and Control Research Network (CPCRN) has been a leader in cancer-related dissemination & implementation (D&I) science. Given increased demand for D&I research, the CPCRN Scholars Program launched in 2021 to expand the number of practitioners, researchers, and trainees proficient in cancer D&I science methods. Methods:

The evaluation was informed by a logic model and data collected through electronic surveys. Through an application process (baseline survey), we assessed scholars’ competencies in D&I science domains/subdomains, collected demographic data, and asked scholars to share proposed project ideas. We distributed an exit survey …


Treatment Methods Of Unstable Expansive Soil Slope Excavation In Overlying Rock Layer In Alpine Region, Shi Xiaobo, Cui Guangyan, Mou Chao, Wen Ye, Xie Feng, Fu Xiaoyang Oct 2024

Treatment Methods Of Unstable Expansive Soil Slope Excavation In Overlying Rock Layer In Alpine Region, Shi Xiaobo, Cui Guangyan, Mou Chao, Wen Ye, Xie Feng, Fu Xiaoyang

Journal of China & Foreign Highway

To deeply study the treatment method for instability of highway cutting slope under the condition of expansive soil overlying rock layer in an alpine region,the comprehensive treatment method of unstable slope under this bad geology was put forward based on the unstable slope project of Zhangbei‒Shangyi Expressway.The governance protection structure consisted of a rigid protection system,drainage system,thermal insulation system,flexible protection system,and waterproof system.The rigid protection system was an anti-slide pile setting at the height of 1/3 of the first grade slope,of which parameters were calculated by cutting the slope of the rock layer in the unstable area to reduce the …


Treatment And Measurement Of Water Inrush During Highway Tunnel Construction, Wang C Haojie, Feng Zhihua, Fan Haobo Oct 2024

Treatment And Measurement Of Water Inrush During Highway Tunnel Construction, Wang C Haojie, Feng Zhihua, Fan Haobo

Journal of China & Foreign Highway

As a special geological condition of highway tunnels,water inrush will cause difficulties in engineering construction technology and management.Unnecessary disputes and management difficulties will emerge when different construction units hold different views about the treatment measures of water inrush,which leads to distributed provisions in the specification and a long treatment period.In view of key problems about the water inrush during highway tunnel construction,including water inrush treatment concept,investigation and estimation,measurement and pricing,and on-site confirmation,this paper systematically sorted out the current regulations and other guiding documents and investigated the treatment methods of tunnel water inrush and reverse slope pumping in China ’s highway …


Review Of Evaluation Methods For Mixing Workability Of Asphalt Mixture, Dong Fuqiang, Zu Yuanzhe, Yu Xin, Chen Bei, Liu Lin Oct 2024

Review Of Evaluation Methods For Mixing Workability Of Asphalt Mixture, Dong Fuqiang, Zu Yuanzhe, Yu Xin, Chen Bei, Liu Lin

Journal of China & Foreign Highway

To clarify the evaluation methods an d research status of mixing workability of asphalt mixture, by consulting relevant research literature in China and abroad and analyzing different evaluation methods,indexes,and research findings of the workability of asphalt mixture,the applicability and evaluation effects of different workability evaluation methods were systematically summarized,and the comparative analysis and comprehensive review were made on the main influencing factors of the mixing workability.The results show that in most evaluation methods for the mixing workability of asphalt mixture,corresponding indexes are constructed to quantitatively evaluate the workability by quantifying the resistance or energy consumption in the mixing process.Besides,in some …


Research Review Of Biomass Ash As Concrete Admixture, Ma Bicong, Liang Jian, Weng Yiling Oct 2024

Research Review Of Biomass Ash As Concrete Admixture, Ma Bicong, Liang Jian, Weng Yiling

Journal of China & Foreign Highway

In order to provide a comprehensive overview of research progress in the use of biomass ash as concrete admixture,the physical and chemical properties,mechanism of action,factors affecting the production process of biomass ash,and the effects of biomass ash incorporation on the working properties,mechanical properties,and durability of concrete were studied.The results show that biomass ash has a smaller density and a larger specific surface area than traditional mineral admixture,and the total amount of active components,namely SiO2 + Al2O3 + Fe2O3 (SAF) in most biomass ashes exceeds the requirements of class F volcanic ash (≥70%).Incorporating biomass ash can effectively improve the mechanical properties …


Compaction Characteristics Of Granular Material And Its Structural Mechanical Behavior Considering Orthotropy, Huang You, Zhang Yunbao, Liu Zhaohui, Pan Yu, Liu Zebin, Fang Ronghai Oct 2024

Compaction Characteristics Of Granular Material And Its Structural Mechanical Behavior Considering Orthotropy, Huang You, Zhang Yunbao, Liu Zhaohui, Pan Yu, Liu Zebin, Fang Ronghai

Journal of China & Foreign Highway

The orthotropy of granular materials is closely related to the compaction process and has a significant impact on the mechanical behavior of pavement structures.In this study,in order to study the effect of the compaction process on the orthotropy of granular materials,different compaction methods and compaction energies were employed to compact granular materials for pavement into specimens,and improved dynamic resilient mechanical tests were conducted.Orthotropic coefficients (α2) of typical granular materials were obtained,and the finite element method was used to conduct mechanical analysis of asphalt pavement structures considering the orthotropy of granular materials.The results show that the dry density of specimens by …


Effect Of Basalt Fiber On Strength Of Cement‑Stabilized Macadam Base, Shu Hongbo, Tang Zhengguang, Zhang Yanhong, Bu Xilian, Liang Dong Oct 2024

Effect Of Basalt Fiber On Strength Of Cement‑Stabilized Macadam Base, Shu Hongbo, Tang Zhengguang, Zhang Yanhong, Bu Xilian, Liang Dong

Journal of China & Foreign Highway

To study the performance of basalt fiber in improving the poor angularity of the crushed cobble base,based on the orthogonal test,this paper determined that the optimal dosage of basalt fiber in the cement-stabilized crushed cobble was 1 kg/m3 (15 mm) + 2 kg/m3 (25 mm).Besides,unconfined compressive strength and splitting strength tests were carried out on mixtures under three working conditions including the cement-stabilized crushed cobble,cement-stabilized crushed cobble with the optimal dosage of basalt fiber,and cement-stabilized macadam (limestone machine-crushed stone ).The results show that influenced by the aggregate angularity,the strength of the cement-stabilized macadam (limestone machine-crushed stone ) mixture is better …


Design And Simulation Of Anti‑Collision System On Independent Pile With External Composite, Liao Yuanyuan, Liu Yu, Zhu Lu, Fang Hai, Zhang Jinrui, Han Juan Oct 2024

Design And Simulation Of Anti‑Collision System On Independent Pile With External Composite, Liao Yuanyuan, Liu Yu, Zhu Lu, Fang Hai, Zhang Jinrui, Han Juan

Journal of China & Foreign Highway

The precise calculation of the ship-bridge collision force is necessary for the assessment of the structural safety of the bridge and the design of an effective anti-collision system.Taking the ship-bridge issue in Furong Bridge in Xiangtan City,this paper compared the collision forces from different angles and in different locations calculated through the finite element software Ansys/LS-DYNA with the results calculated through the empirical formula,thereby determining the fortification collision forces of the bridge piers.Based on the weak anti-collision ability of the bridge double-limb thin-walled pier,the paper designed and implemented a new anti-collision system combined with composite and concrete-filled steel independent piles.The …


Intelligent Recognition Technology Of Highway Cracks Based On Semantic Segmentation, Gao Liang, Rao Faqiang, Yang Zhongmin, Dai Zongsheng, Sun Hao Oct 2024

Intelligent Recognition Technology Of Highway Cracks Based On Semantic Segmentation, Gao Liang, Rao Faqiang, Yang Zhongmin, Dai Zongsheng, Sun Hao

Journal of China & Foreign Highway

Real-time detection and timely treatment of highway cracks are crucially fundamental for vehicle safety.Rapid identification and comparison of cracks is a new method for monitoring the development and changes of geological disasters especially when they induce cracks.Therefore,this study proposed an intelligent recognition method of highway cracks based on semantic segmentation,establishing a model with dataset,neural network,calculation parameters,and evaluation indicators to rapidly identify the cracks.The results show that,firstly,when the neural network Attention U-net built in this study semantically segments highway cracks,the binary cross loss function value and accuracy rate reach 0.008 7 and 0.998 4,respectively.Secondly,compared with traditional algorithms,the semantic segmentation method shows …


Lessons Learned From 60 Years Of Pavement Trials In Continental Climate Regions Of Canada And Future Perspective, Wang Di, Li Jingxiao, Ren Xueyuan, Zhang Fan, Yuan Dongdong Oct 2024

Lessons Learned From 60 Years Of Pavement Trials In Continental Climate Regions Of Canada And Future Perspective, Wang Di, Li Jingxiao, Ren Xueyuan, Zhang Fan, Yuan Dongdong

Journal of China & Foreign Highway

During the early 1960 s,Canadian road authorities began using stiffer asphalt to address the issue of early rutting in the wheel track zone of asphalt pavements,which was caused by the growing traffic volumes.Pavements constructed with stiffer asphalt commonly exhibit evenly spaced transverse cracks due to the significant internal stresses caused by low temperatures and the inadequate resistance of the asphalt to cracking under such conditions.Research conducted on asphalt pavements with cracks caused by low temperatures has verified the significant impact of asphalt ’s consistency,temperature sensitivity,phase uniformity,and durability.In order to tackle the difficulties presented by the utilization of modified asphalt in …


Method Of Solving Initial Construction Cable Force Of Completed Cable‑Stayed Bridge, Xu Yufeng, Chen Si, Xie Yunfei, Zhu Mengyang Oct 2024

Method Of Solving Initial Construction Cable Force Of Completed Cable‑Stayed Bridge, Xu Yufeng, Chen Si, Xie Yunfei, Zhu Mengyang

Journal of China & Foreign Highway

To solve the initial construction cable forces of a completed cable-stayed bridge,a method that combines unstressed cable length and forward-iteration is proposed.Firstly,the unstressed length of each cable is calculated according to the completed bridge state.Then,the initial cable forces are obtained by using the unstressed cable length for the forward analysis.The initial construction cable forces are adjusted by difference iteration.Finally,the initial construction cable forces are fine-tuned according to the deformation of the pylon deformation to obtain the bridge completion state that satisfies the deviation requirements.The proposed method is employed in a cable-stayed bridge with a known completion state to calculate the …


Experimental Study On Influence Of Stress Ratio On Fatigue Life Of High Strength Steel Wire, Zeng Yi, Yan Donghuang, Xu Hongsheng, Yang Ying Oct 2024

Experimental Study On Influence Of Stress Ratio On Fatigue Life Of High Strength Steel Wire, Zeng Yi, Yan Donghuang, Xu Hongsheng, Yang Ying

Journal of China & Foreign Highway

To clarify the influence of stress ratio on the fatigue life of high strength steel wire and verify the applicability of the fracture mechanics model to evaluate the fatigue life of steel wire,based on the assumption of equating wire corrosion pits to notches,fatigue tests were carried out on steel wire samples with different prefabricated notch depths at different stress ratios,and a fatigue life empirical equation considering the stress ratio effect was established.The results show that the fatigue life of the steel wire samples is significantly influenced by the stress ratio,which decreases with the increase in the stress ratio.The increase in …


Influence Of High Temperature On Large Cantilever Construction Control Of Wide Extradosed Cable‑Stayed Bridge, Zhu Haojie, Zhang Xiedong, Li Yong, Lin Yuan, Wu Di Oct 2024

Influence Of High Temperature On Large Cantilever Construction Control Of Wide Extradosed Cable‑Stayed Bridge, Zhu Haojie, Zhang Xiedong, Li Yong, Lin Yuan, Wu Di

Journal of China & Foreign Highway

In order to investigate the influence of temperature gradient on the construction of wide extradosed cable-stayed bridges in the large cantilever construction stage at high temperatures,the solar radiation and thermal boundary conditions of wide equal-height box girder were theoretically calculated,and the thermal analysis finite element model of the wide equal-height box girder was established by Abaqus.The cross-section temperature of the box girder was measured by intelligent string sensors and an infrared thermometer.The temperature gradient and its distribution of wide equal-height box girder from sunrise to sunset on a certain day in summer were calculated.The finite element model of the construction …


Back‑Calculation Of Subgrade Modulus Based On Genetic Algorithm And Viscoelasticity Theory, Dai Fugui, Wang Xihui, Wu Yaguang, Li Hai Oct 2024

Back‑Calculation Of Subgrade Modulus Based On Genetic Algorithm And Viscoelasticity Theory, Dai Fugui, Wang Xihui, Wu Yaguang, Li Hai

Journal of China & Foreign Highway

To improve the applicability of the PFWD detection method for the back-calculation of subgrade modulus,taking the subgrade splicing project of the west loop line in Nairobi as an example,this paper adopted 3D Kelvin viscoelasticity model and quasi-static response analysis to deduce the displacement function of viscoelastic subgrade under long-term fixed loads,and combined the principle of liner superposition of viscoelasticity with genetic algorithm to propose a new method based on multi-population genetic algorithm for the modulus back-calculation of viscoelastic subgrade.Among them,the corresponding program for back-calculation was written by Matlab.The comparison between theoretical derivation and field tests shows that the peak value …


Overall Design Concept Of Municipal Reconstruction Of Cross‑City Expressway, Fu Yuankun, Zhang Yu Oct 2024

Overall Design Concept Of Municipal Reconstruction Of Cross‑City Expressway, Fu Yuankun, Zhang Yu

Journal of China & Foreign Highway

The municipal reconstruction of the cross-city expressway is of great significance in enlarging the urban framework,refining the spatial pattern,and promoting the integrated development of clusters.However,China’s expressways seldom undergo municipal reconstruction,with less synergy formed with cities.Therefore,taking one case described above in Hebei Province as an example,this article proposed the overall design concept of integrating with the city from urban space,road networks,municipal facilities,urban ecology,cultural landscape,and other perspectives after analyzing problems in urban space,traffic,industry,landscape and urban quality in existing cross-city expressways. In addition,this paper studied and optimized the municipal reconstruction plan.Holding a theme of “municipalization ”,the plan eliminated the fragmentation of urban space …


Progress And Prospects Of Road Engineering Disease Treatment Technology In Permafrost Regions, Gao Feng, Zeng Xianzhang, Zhong Wenhua, Huang Shengyong, Zhang Junhui Oct 2024

Progress And Prospects Of Road Engineering Disease Treatment Technology In Permafrost Regions, Gao Feng, Zeng Xianzhang, Zhong Wenhua, Huang Shengyong, Zhang Junhui

Journal of China & Foreign Highway

Freeze-thaw disasters are key issues affecting the service performance and operational safety of road projects in permafrost regions.Under the combined influence of warming and humidification of the permafrost environment and engineering thermal effects,the degradation of permafrost is accelerating,exacerbating the risk of road freeze-thaw diseases.Roads in these regions are more frequently maintained and repaired to ensure service performance,with a service life lower than designed.Therefore,deepening the understanding of the disaster mechanism of road geotechnical structures and strengthening the study on engineering disease treatment technology are of great significance in promoting the construction and maintenance of high-quality and high-grade highways in frozen regions.This …


Model Test On Soil Deformation Mechanism And Damage Mode Caused By Mud Leakage From Drilled Piles In Karst Area, Jiang Mingying, Chen E ’Mei, Liu Yongcheng, Zhu Yadong, Jiang Wenkui, Xie Ruiting Oct 2024

Model Test On Soil Deformation Mechanism And Damage Mode Caused By Mud Leakage From Drilled Piles In Karst Area, Jiang Mingying, Chen E ’Mei, Liu Yongcheng, Zhu Yadong, Jiang Wenkui, Xie Ruiting

Journal of China & Foreign Highway

Pile holes are often drilled through cavities in karst areas,which induces mud leakage and causes hole wall instability,ground collapse,or equipment trapping and hinders smooth construction.It is important to know the collapse mechanism of boreholes due to mud leakage,so as to optimize and determine the construction process of pile holes.In this paper,indoor model tests were used to study the deformation mechanism and damage mode of soil caused by drilling through cavities and mud leakage in pile holes under the conditions of upper clay and lower sandy soil in the karst area,so as to provide an experimental basis for the decision of …


Deformation Measurement And Safety Warning Of Highway Bridges Based On Machine Vision, Su Ziyue, Du Wenkang, Lei Dong Oct 2024

Deformation Measurement And Safety Warning Of Highway Bridges Based On Machine Vision, Su Ziyue, Du Wenkang, Lei Dong

Journal of China & Foreign Highway

The structural safety of highway bridges plays a crucial role in traffic safety operations and regional economic development.Due to the rapid increase and complex changes in traffic loads,the demand for real-time monitoring of bridge ’s structural deformation and safety conditions has been increasingly prominent.However,the structural health monitoring system,dominated by contact sensors,has limitations such as difficult installation and construction,complicated maintenance and replacement,and the need to interrupt traffic.To this end,a non-contact deformation measurement system based on machine vision was proposed.Template matching and feature point recognition methods were utilized to achieve recognition of structural surface markings and displacement extraction of key positions.The accuracy …


Properties And Application Of Cement Improved Loess Under Low Temperature Environment In Cold Region, Li Xiangyang Oct 2024

Properties And Application Of Cement Improved Loess Under Low Temperature Environment In Cold Region, Li Xiangyang

Journal of China & Foreign Highway

According to the cold climate and low annual average temperature in cold regions of China,the field curing conditions of cement improvement of collapsibility loess under low temperature,room temperature,and medium temperature were simulated at 5 ℃,10 ℃,20 ℃,and 30 ℃,respectively.Based on laboratory experiments,this study analyzed the effects of curing temperature,cement content,and curing age on RCBR,unconfined compressive strength,and dynamic resilience modulus of cement improved loess.The effects of cement content and curing temperature on freeze-thaw durability and erosion resistance of cement improved loess were studied by the freeze-thaw cycle test and dynamic water erosion test.Combined with the laboratory results,the 4% and 5% cement …


Effect Of Chloride Ions On Salt Expansion Of Salinized Subgrade Fill Soil In Cold Regions, Hu Wenzhu, Wang Zhaowei, Cao Yong, Zhang Jing, Bai Ruiqiang Oct 2024

Effect Of Chloride Ions On Salt Expansion Of Salinized Subgrade Fill Soil In Cold Regions, Hu Wenzhu, Wang Zhaowei, Cao Yong, Zhang Jing, Bai Ruiqiang

Journal of China & Foreign Highway

Salinized subgrade fill soil in cold regions typically comprises composite saline soil rich in sodium chloride and sodium sulfate.This study aimed to explore the mechanism of the effect of chloride ion content on salt expansion of the salinized subgrade in cold regions.Based on the calculation theory of the sodium chloride-sodium sulfate-water ternary system solution in the Pitzer ion model and combined with the FREZCHEM model,the study quantitatively analyzed the intrinsic connection between water activity,freezing factor,and supersaturation ratio with temperature and concentration ratio (η=mCl-/mSO2-4).It investigated the variation patterns of the freezing temperature and crystallization supersaturation ratio of composite saline soil with …


Correlation Between Pavement Distress And Structural Hidden Distress, Liu Xianming, Xia Han, Hu Dongping, Yan Chen, Yang Rui, Zhong Xinran Oct 2024

Correlation Between Pavement Distress And Structural Hidden Distress, Liu Xianming, Xia Han, Hu Dongping, Yan Chen, Yang Rui, Zhong Xinran

Journal of China & Foreign Highway

The hidden distress in the pavement structure does great harm to the performance and service life of the road.In this work,based on the statistical idea of pavement distress rate in the Highway Performance Assessment Standards (JTG 5210—2018),an index of characterizing hidden distress in the pavement structure,namely pavement structure distress rate,was proposed.Based on the actual highway inspection project,the pavement distress and the hidden distress in the depth of 1 m below the pavement of a two-way four-lane highway with a length of 38 km were studied.The overall situation of pavement distress and hidden distress and their spatial distribution were analyzed statistically …