Site Investigation Research Articles

Analysis of UAV Flight Patterns for Road Accident Site Investigation

Unmanned Aerial Vehicles (UAVs) offer a promising solution for road accident scene documentation. This study seeks to investigate the occurrence of systematic deformations, such as bowling and doming, in the 3D point cloud and orthomosaic generated from images captured by UAVs along an horizontal road segment, while exploring how adjustments in flight patterns can rectify these errors. Four consumer-grade UAVs were deployed, all flying at an altitude of 10 m while acquiring images along two different routes. Processing solely nadir images resulted in significant deformations in the outputs. However, when additional images from a circular flight around a designated Point of Interest (POI), captured with an oblique camera axis, were incorporated into the dataset, these errors were notably reduced. The resulting measurement errors remained within the 0–5 cm range, well below the customary error margins in accident reconstruction. Remarkably, the entire procedure was completed within 15 min, which is half the estimated minimum duration for scene investigation. This approach demonstrates the potential for UAVs to efficiently record road accident sites for official documentation, obviating the need for pre-established Ground Control Points (GCP) or the adoption of Real-Time Kinematic (RTK) drones or Post Processed Kinematic (PPK) technology.

257. Shared antibody sequences reveal novel public clonotypes of antibodies within and between HIV infected and healthy individuals

Abstract Background Public clonotypes, antibodies against specific antigens in unrelated individuals that have genetic similarities, have been shown in a variety of infections, including SARS-CoV-2 and HIV. These can be exploited as potential diagnostics and to identify past infections that may be related to post-infectious disorders, such as Kawasaki disease, Multiple Sclerosis or Alzheimer's disease. Methods Heavy chain variable sequences were retrieved from public biorepositories (Bioprojects PRJNA486667, PRJNA638224,PRJNA527941) from 270 subjects. These were derived from labeled cohorts: Healthy (116), HIV broadly neutralizing (46), HIV non-broadly-neutralizing (50), HIV-negative (43), and COVID-19 (15). We utilized the Immcantation package of software run on our SUNY Buffalo computational cluster. After PRESTo annotation, duplicate sequences were collapsed and sequences of only single counts were removed. Clonal groups were determined using SCOPer requiring IGHV, IGHJ, and CDR3 amino acid sequence to be perfectly matched. Figures and statistics were generated with immcantation, excel, pandas, and graphpad prism 8. Results There were 5.5 million unique heavy chain sequences from 32 million sequences. Defining public clonotypes as completely sharing CDR3 amino acid sequence and having predicted same germline variable, D, and J chains, 6861 (0.12%) shared clones were found. The distributions of CDR3 lengths showed skewing to shorter CDR3s (mean length of 10.5). There were no stringently defined clones noted in all members. Within HIV infected persons the two most shared clones both used VH1-18, JH4, had CDRaa 8, and were immature IGM/D. Three clones were used in near 10% of cases across both non-HIV and HIV datasets with prominent usage of VH 4 family members and were less mutated and IGM/D. There were eight clones solely shared > 10% within non-HIV/non-Covid infected individuals, with the top shared clones all consistent with matured IGG responses with prominent predicted use of VH3-7 and a number of novel CDR3s noted. Predicted CDR3 length using incantation was compared for cohort of clones that shared predicted V, D, J usage and the exact CDR3 amino acids between individuals. This distribution failed normality testing. Conclusion Identification of public clonotypes will show stochastic bias toward shorter CDR3 regions. There were differences between HIV and non-HIV cohorts and a number of novel public clonotypes were found. Disclosures Mark D. Hicar, MD/PhD, Pfizer: site investigator for 2 trial

Stochastic numerical analyses to investigate the effects of the spatial nonuniformity of offshore ground on the serviceability of monopile foundations

ABSTRACT The evidence of soil nonuniformity has been reported in several site investigation reports and is well-confirmed for any soil in general. However, studies related to the spatial soil variability of offshore ground are somewhat limited, and current design practices for monopile foundations also overlook the uncertainty of the offshore ground. This paper presents the probabilistic evaluation of the serviceability limit state of monopile foundations considering the spatial variability of offshore ground. The nonuniformity of the ground is modeled utilizing the site-specific undrained shear strength (su) as a stochastic variable, using a spatially correlated Gaussian random field. A hardening soil constitutive model is utilized in 3D finite element analysis of offshore ground, with a focus on parameter calibration. The reliability of the serviceability limit state is assessed based on the allowable load on the pile head. The stochastic behavior of the maximum bending moment and maximum shear force along the depth of the monopile is also investigated. Besides, the paper also highlights the importance of incorporating ground nonuniformity during the design process of a monopile foundation.

From power to architecture: an analysis on the identity transformation of Tagaytay people’s park in the sky through edifice complex and democratization theory

The study of architecture in relation to the principles of political power places a different perspective in understanding how the built environs with heritage value were shaped in time and are being constantly shaped at the present. Its relevance cannot be understated, as in spite of its actuality, it is a side of the field that may still be considered sensitive to some. Architecture is never neutral. It corresponds to the patron’s ideals, intentions, and ideological orientation, communicated by the designer through his technical knowledge in artistic articulation of forms. In a larger scale, architectural identity can therefore be affected by those possessing power and can serve as tactile channel in redirecting society. This study presents the case of People’s Park in the Sky in the Philippines, a colossal brutalist mansion, originally named Palace in the Sky, situated at Mt. Sungay peak in Tagaytay City. Commissioned in 1981 by Imelda Marcos, the wife of authoritarian head Ferdinand Marcos, the palace was not completed and eventually transformed into a public urban park. Supported by the concept of Edifice Complex and Democratization theory, methodical assessment of the political links of the said architecture was executed in two parts: examination of historical accounts and first-hand site investigations. The findings of the analysis revealed that there is a present architectural crisis in the park, emerging from its long-time neglect since the 1986 transition years, and if not taken proper institutional action, its genuine identity and legacy could be forgotten and eventually lost in the near future.

Variations in strength and stiffness of cement-stabilized reclaimed asphalt pavement and marginal lateritic soil blends in tropical climate

This article investigated the effects of temperature on the variations in strength and stiffness of cement-stabilized reclaimed asphalt pavement (RAP) and marginal lateritic soil (MLS) as a sustainable bound base course of flexible pavement. A site investigation to assess the temperature profile of highway pavement in the northeast of Thailand was conducted to find the temperature variation of pavement structure in tropical country. Laboratory tests including unconfined compressive strength (UCS), modulus of elasticity (E50), and indirect tensile strength (ITS) tests were conducted on cement-stabilized RAP and MLS blends at varying mix proportions and temperatures. It is evident that the temperature significantly affects the strength and stiffness of specimens containing RAP due to the presence of bitumen covering the RAP aggregate. The additional MLS and cement can reduce the viscoelasticity of RAP aggregate. The strength reduction due to the temperature is characteristic of the RAP mixtures with MLS and cement. The normalized relationships of UCS and temperature and the empirical correlations between E50 and ITS versus UCS were presented. This set of relationships is a valuable tool for the mix design of cement-stabilized RAP and MLS blends as a bound base course in tropical countries.

Quantifying CPT cone factors in clays derived from weathered mudstone

The empirical interpretation of cone penetration test (CPT) cone factors ( N k ) can be subject to considerable variability for clays derived from weathered mudstones, leading to significant deviations in the estimation of undrained shear strength ( S u ). This paper presents a comparison of triaxial and CPT data from a site investigation in clays derived from weathered mudstones in central England. Corrected cone factors ( N kt,UU ) were derived from a one-to-one comparison of 94 pairs of unconsolidated, undrained triaxial and CPT data from equivalent depths. The performance of the cone factors was evaluated using a training set (75 pairs) and a test set (19 pairs). A parametric study was used to explore the variability of N kt,UU , quantified using the coefficient of variation (COV Nkt,UU ), for varied separation distance thresholds ( D s ) between individual triaxial and CPT data. The absolute deviation between the laboratory shear strength ( S u(Lab) ) and that predicted from CPT profiles (S u(CPT) ) was not sensitive to N kt,UU values in the range 25 < N kt,UU < 31. The parametric study showed that D s could be increased from 50 to 250 m, to include more data pairs for estimates of N kt,UU , without substantially increasing COV Nkt,UU .

Landslide susceptibility assessment in multiple urban slope settings with a landslide inventory augmented by InSAR techniques

Landslide susceptibility assessment (LSA) evaluates the likelihood of landslide occurrences and can help mitigate and prevent landslide risks. Recently, there have been vast applications of data-driven LSA methods owing to the increased availability of high-quality satellite data and landslide inventories. However, two issues remain to be addressed, as follows: (a) Items in a landslide inventory are mainly historical landslides from the interpretation of optical images and site investigation, resulting in predictive models trained with these items being insensitive to undetectable slope movements, such as slow-moving landslides that have not yet occurred; (b) Most study areas contain a variety of landslide-prone geographical settings that a single model can not accommodate well. Considering the complex landslide causes in Hong Kong with a land area of approximately 1108 km2, we proposed the utilization of multi-temporal InSAR techniques to generate weak landslide samples from slopes with ground surface movements for landslide inventory augmentation; and meta-learn intermediate representations for the fast adaptation of LSA models corresponding to different landslide-prone geographical settings. Besides, we performed feature permutation to identify dominant landslide-predisposing factors. The LSA results in Hong Kong revealed that slope deformation in several mountainous areas is closely associated with the occurrence of recorded landslides. By augmenting the landslide inventory using InSAR techniques, the proposed method enhanced the LSA models' capacity to identify slow-moving landslides and achieved better statistical performance. The discussion highlights that slope and stream power index (SPI) are the key landslide-predisposing factors in Hong Kong, but the dominant landslide-predisposing factors will vary under different geographical conditions. By comparison with the methods that treat LSA as a binary classification problem, such as support vector machine, multilayer perceptron, deep belief network, and random forest based LSA methods, the proposed method entails a fast-learning strategy and outperforms these methods in data-driven model evaluation indicators, e.g., by 3–6% in accuracy, 2–6% in precision, 1–2% in recall, 3–5% in F1-score, and approximately 10% in Cohen Kappa. The information about the relative importance of landslide predisposing factors, derived through feature permutation, can foster guidance for targeted landslide prevention schemes, such as constructing and maintaining slope consolidation facilities in areas where slope is the dominant landslide-predisposing factor.

Enhancing open clinical trials through blinded evaluations: an exploration with diabetic foot infections

BackgroundBlinding drugs through simulation techniques is an important means to control the subjective bias of investigators and subjects. However, clinical trials face significant challenges in the placebo production of drugs, and many trials cannot be double-blinded.ObjectiveThis study was conducted to ascertain the consistency between non-blind and blind evaluation results in clinical trials and to pioneer strategies to control information bias, particularly in trials where double-blinding is not feasible.MethodsIn this investigation, a randomized controlled trial (RCT) studying diabetic foot infections (DFIs) was utilized as a representative case. In this trial, the grading of DFIs, as per guidelines by the Infectious Disease Society of America (IDSA) and International Working Group on Diabetic Foot (IWGDF), was used as the primary efficacy indicator. A sample of sixteen patients was randomly chosen from the RCT, and DFI grading was assessed jointly by both non-blinded investigators and blinded center-reading investigators. A consistency test was then deployed to compare the evaluation results, forming the basis for our proposed strategies for effective blinded evaluation. In addition, other perspectives were collected at the end of this study, including with those involved in designing and conducting the recent blinded evaluation trial.ResultsFive subjects were excluded due to the quality of photos or the lack of post-treatment visits. The post-treatment IDSA/IWGDF grading results were compared in 11 subjects (experimental group=6, control group=5), and the consistency test showed inconsistent results between the non-blinded and center reading blinded evaluations (Kappa=0.248, p=0.384). In the experimental group, three cases were judged as grade 1 in the non-blinded evaluation and grade 2 in the central reading blinded evaluation; in the control group, three cases were judged as grade 2 in the non-blinded evaluation and grade 1 in the central reading blinded evaluation. The sum of these two cases in 22 post-treatment determinations was 27% (6/22). Furthermore, researchers propose several strategies for implementing blinded evaluations in clinical trials after this trial, which encompass aspects such as staff allocation, training, participant management, trial drug administration, efficacy indicator collection, and safety event management.ConclusionsThe study highlighted that evaluations from non-blinded site investigators may potentially exaggerate the efficacy of the experimental group and that deep wounds can present challenges for observation via center-reading photos. These findings underline the vital necessity for objective assessment in open clinical trials, especially those where wound observation serves as the primary efficacy indicator. The study suggests the adoption of independent blinded investigators at each site, complemented by a comprehensive set of standard operating procedures for blinding evaluation. These measures could serve as an effective counterbalance to subjective bias, thereby augmenting the credibility and consistency of results in open clinical trials. The implications of these findings and recommendations could be of great significance for the design and execution of future open clinical trials, potentially bolstering the quality of clinical research in this area.Trial registrationChiCTR2000041443. Registered on December 2020

A geological and geotechnical information system (GEO-GIS) for urban planning and its application to the Acıpayam Basin (Denizli, Turkey) with some observations from a M w 5.5 earthquake on 20 March 2019

There are many site investigation projects used for the urban planning of a city. They are archived in hard copy or scanned in image files stored on computers. In this study, geological, geotechnical and geophysical data obtained from different site investigation projects in the Acıpayam district were evaluated in the same coordinate system using a geological and geotechnical information system (GEO-GIS) computer program. The Acıpayam GEO-GIS database includes field tests in 82 boreholes, 85 observation pits, laboratory test results of soil samples, 99 seismic refraction measurements and 70 microtremor measurements. Required information from the database can be displayed at its spatial coordinates on a base map and new maps can also be drawn using the GEO-GIS database system. Resultant maps drawn using the Acıpayam GEO-GIS database show that in the northern and eastern parts of the Acıpayam district, where the Oğuz, Kırca, Yassıhöyük, Apa, Ovayurt, Karahüyük, Ucarı and Gedikli villages are located, weak soil layers exist. This means that some damage may be caused to adobe and masonry buildings in the villages during shaking associated with strong earthquakes, as observed after the 5.5 (M w ) earthquake that occurred on 20 March 2019. The Acıpayam GEO-GIS database system is a useful tool for engineers and planners that can assist in drawing GIS-produced maps for geotechnical evaluations of the basin. These maps can be used in decision-making projects for urban planning. Thematic collection: This article is part of the Leading to Innovative Engineering Geology Practices collection available at: https://www.lyellcollection.org/topic/collections/leading-to-innovative-engineering-geology-practices

Abstract 12495: Modes of In-Hospital Death in Patients With Cardiogenic Shock (CS): An Analysis From the Critical Care Cardiology Trials Network (CCCTN)

Introduction: Mortality from cardiogenic shock (CS), a syndrome of multi-organ system dysfunction, remains high. However, data regarding how patients with CS expire are limited and may have implications for designing clinical trials, identifying therapeutic strategies, and improving outcomes. Aim: We sought to describe primary modes of in-hospital death among patients admitted with CS to cardiac intensive care units (CICUs). Methods: CCCTN is a multi-national research network of advanced CICUs coordinated by the TIMI Study Group (Boston, MA). Using standardized definitions, site investigators classified the direct mode of in-hospital death for patients with CS. Categories included 8 possible modes of cardiovascular (CV) and non-CV death ( Fig ). Subgroups defined by cardiac arrest prior to CICU admission and use of mechanical circulatory support (MCS) were explored. Results: Among 1098 CS cases captured from 10/2021-09/2022, 358 (32.6%) died during the index hospitalization with a median time to death of 4.3 (Q1-Q3, 1.1-10.9) days from CICU admission. Among the deaths, 50%, 41%, and 9% occurred in the context of HF-CS, AMI-CS, and secondary CS, respectively. Overall, mode of death was CV in 82% of cases ( Fig A ). Refractory CS was the dominant mode of death (66%), followed by arrhythmia (13%), anoxic brain injury (6%), and respiratory failure (5%; Fig A ). Compared to patients without preceding cardiac arrest, those with cardiac arrest prior to CICU admission were more likely to die from anoxic brain injury (10% vs. 1%; p<0.01; Fig B ). Compared to patients managed without MCS, those with MCS were more likely to die from refractory shock (p<0.01), either cardiogenic (74% vs. 61%) or non-cardiogenic (6% vs. 3%; Fig C ). Conclusions: Most in-hospital deaths in patients with CS are related to direct CV causes, particularly refractory CS. However, there is potentially important heterogeneity in mode of death across subgroups defined by preceding cardiac arrest and use of MCS.

Characterization of Site Amplification by a Parametric Study

ABSTRACT The reliability of V s30 and the performance of alternative time averaged shear wave velocities (V sz ) and shear wave travel times (T tz ) at various depths, z, were investigated for the estimation of site amplification and fundamental frequency (f 0) characterization by considering the linear and nonlinear soil behavior. The study revealed that alternative parameters performed better than V s30 and the best performing z parameters changed by switching from convex to concave theoretical profiles and by increasing ground motions. For a practical usage in site investigations, guidelines to estimate nonlinear soil amplification factor and fundamental frequency from the linear ones were presented.

An Engineering Geological Appraisal of the Leakage Problem in Dora-1 Earthen Dam, Tigray: Implications for its Stability

Leakage is one of the major problems facing the functionality and sustainability of dams. It occurs through the embankment body, reservoir, foundation, and abutments. This study was conducted to identify the main causes of the leakage problem at the Dora-1 dam, located in the northern part of Ethiopia. It is an earthfill dam with a height of 43.5 m, crest length of 454 m, and reservoir capacity of 4.67 million cubic meters. Part of the embankment body was wet and swampy up to 20 m high from the ground due to leaking water. Geological investigation, laboratory test of the construction materials (including grain size analysis, specific gravity and water absorption, Atterberg limit, free swell, dispersion, permeability, and shear strength), and electrical resistivity investigation were used to identify and pinpoint the possible causes of the leakage problem. Results of the study show that the favorable geological features responsible for the occurrence of leakage include: (a) geological contact between sandstone and moderately to highly weathered basalt unit at the left abutment, (b) the gravelly sand deposit at the central foundation and (c) dyke outcrop at the river course within the reservoir running in the upstream-downstream direction. Results of laboratory tests for clay core show medium to high compressibility, good to poor workability, and semi-pervious to impervious permeability when compacted. The water absorption and the percentage finer of the filter material don’t satisfy the filter criteria and the shell material was found to be semi-previous. The anomalous in the resistivity survey result confirms the situation. Slope stability analysis of the embankment showed instability conditions at full reservoir level. Close follow-up and a downstream stabilization structure, including rock and gravel support, were recommended.
 Construction material; Embankment dam; Site investigations; Ethiopia.

Status of the Site Investigation and Site Selection Process for a Deep Geological Repository in Switzerland

Nagra, the National Cooperative for the Disposal of Radioactive Waste, in Switzerland, is realizing a project of the century: the planning, construction, operation, and closure of a deep geological repository (DGR) for the nation’s radioactive waste. The site selection process for a DGR is regulated by a three-stage process described in the Sectoral Plan, which the Federal Government approved in 2008. An overconsolidated shale, the Opalinus Clay, was selected as the most suitable rock formation as a result of Stage 2 of the Sectoral Plan. The three remaining siting regions were investigated in detail during Stage 3, including more than 12.5 km of exploratory boreholes drilled since 2018 and high-resolution, three-dimensional seismic surveys covering an area of approximately 250 km2. In September of 2022, Nagra proposed Nördlich Lägern as the preferred siting region for a combined repository in Northern Switzerland. Nagra plans to submit the corresponding general license application to the authorities by the end of 2024.

Endpoint adjudication in cardiovascular clinical trials.

Endpoint adjudication (EA) is a common feature of contemporary randomized controlled trials (RCTs) in cardiovascular medicine. Endpoint adjudication refers to a process wherein a group of expert reviewers, known as the clinical endpoint committee (CEC), verify potential endpoints identified by site investigators. Events that are determined by the CEC to meet pre-specified trial definitions are then utilized for analysis. The rationale behind the use of EA is that it may lessen the potential misclassification of clinical events, thereby reducing statistical noise and bias. However, it has been questioned whether this is universally true, especially given that EA significantly increases the time, effort, and resources required to conduct a trial. Herein, we compare the summary estimates obtained using adjudicated vs. non-adjudicated site designated endpoints in major cardiovascular RCTs in which both were reported. Based on these data, we lay out a framework to determine which trials may warrant EA and where it may be redundant. The value of EA is likely greater when cardiovascular trials have nuanced primary endpoints, endpoint definitions that align poorly with practice, sub-optimal data completeness, greater operator variability, and lack of blinding. EA may not be needed if the primary endpoint is all-cause death or all-cause hospitalization. In contrast, EA is likely merited for more nuanced endpoints such as myocardial infarction, bleeding, worsening heart failure as an outpatient, unstable angina, or transient ischaemic attack. A risk-based approach to adjudication can potentially allow compromise between costs and accuracy. This would involve adjudication of a small proportion of events, with further adjudication done if inconsistencies are detected.

Intelligent nuclear decommissioning solution: Code for site characterization and management of overall surveys

The site characterization should be conducted during the entire decommissioning period to verify the compliance with regulatory guidance and to demonstrate the safety for site release. A technical manual called Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) has been widely used as a reference for the site characterization. Historically, it has required enormous resources because of extensive data handling. And there is a possibility of a human error because of the expert’s judgement reliance. In this study, software called COde for Site characterization and Management of Overall Surveys (COSMOS) has been developed with Artificial Intelligence (AI) models. One of the AI model is possible to revolutionary reduce time for finding keyword related contamination, and the other manages database by digitalizing drawings. Also, other survey modules are possible to conduct related all of statistical tests. In the end, COSMOS would be utilized as a total management solution for site characterization.

Challenges and Lessons Learnt Learned from Industry-Driven Multi-Centre Global Clinical Trials in IgA Nephropathy (IgAN): Site Investigators' Perspective

Challenges and Lessons Learnt Learned from Industry-Driven Multi-Centre Global Clinical Trials in IgA Nephropathy (IgAN): Site Investigators' Perspective

Exploring the role of decentralized clinical trials in oncology: Insights from cancer centers.

105 Background: Decentralized clinical trials (DCT) involve conducting some or all trial-related activities at a location separate from the investigator's site. DCT can help reduce the burden on patients, sites, and sponsors while improving patient accrual and retention rates and increasing the diversity of trial participants. While DCT methods provide patient-centric trial flexibilities, they can impact trial operations. This survey aimed to gain insights into the perspectives and experiences of cancer centers regarding DCT in the field of oncology. Methods: A 13-question survey that addressed prior experience, perceived benefits, and challenges in implementing DCT was developed by members of the Association of American Cancer Institutes (AACI) Clinical Research Innovation (CRI) Steering Committee. The survey was sent via email to the AACI CRI listserv, which consists of members of 90 cancer research centers in North America. Respondents were asked to consider their activity related to treatment and non-treatment interventional trials. Results: There were 75 total responses from members affiliated with 55 individual cancer centers. Of these centers, 73% were NCI-designated cancer centers. Of the individual respondents, 57% were clinical trial office administrators. The issues of highest concern by respondents were 1) meeting study timelines, 2) patient recruitment and 3) cost (83%, 65%, 44% respectively). All respondents had prior experience with DCT tools with the most common components being the use of local facilities for labs/imaging, telemedicine and e-consent (89%, 69%, 68% respectively). The areas of most perceived benefit from DCT include reduced participant burden, increased diversity and participant retention (81%, 80%, 68% respectively) while areas of perceived challenges include quality control, regulatory compliance and cost (61%, 59%, 49% respectively). While 92% respondents agreed/strongly agreed that DCT can improve clinical trial access, 92% agreed/strongly agreed that additional site staff training is required for successful DCT implementation. Conclusions: DCT tools have been widely implemented in oncology trials with all surveyed sites reporting prior experience. This survey emphasizes the perceived benefits of DCT in oncology, while underscoring the importance of addressing challenges and meeting the specific requirements of cancer centers. Future work should identify specific areas that require additional staff training to enable DCT readiness.

Metal-organic framework-derived cation regulation of metal sulfides for enhanced oxygen evolution activity

Heteroatom doping serves as an important strategy to improve the oxygen evolution reaction (OER) activity of transition-metal compounds, while the investigation of intrinsic active sites and mechanisms remains insufficient. In this work, a facile cation regulation strategy is reported to boost the OER activity of metal sulfides via pyrolysis of the Ni-Co bimetallic metal-organic framework. The obtained Ni-substituted CoS nanoparticles on nitrogen-doped mesoporous carbon (Ni-CoS/NC) catalyst achieves a current density of 10 mA cm−2 at a small overpotential of 270 mV with a Tafel slope of 37 mV dec−1 in 1.0 mol L−1 KOH. Through a combination of spectroscopy study and theoretical computations, the activity origin is revealed at the atomic level. The CoxNi1–xOOH serves as the real active site for the OER generated by the Ni-CoS/NC reconstruction under oxidation potential during OER. The Ni substitution results in a strong electronic interaction between the two metals, thus generating more negatively charged Co atoms and more positively charged Ni atoms in the electrocatalyst. The metal sites with regulated electronic structure exhibit enhanced surface adsorption of OOH* and reduce the OER overpotential. Meanwhile, the conductive porous carbon scaffold facilitates electron transfer, mass diffusion, and the accessibility of active sites. This work not only provides a feasible cation regulation strategy for the design of high-performance electrocatalysts for low-cost energy storage and conversion systems, but also yields fresh insight into the activity enhancement mechanisms and intrinsic active sites.

Improved resistance prediction and reliability for bridge pile foundation in shales through optimal site investigation plans

Improved resistance prediction and reliability for bridge pile foundation in shales through optimal site investigation plans

A CPT-Based Design Framework for Uplifted Open-Ended Piles Installed in Spatially Variable Sandy Soils. II: Implications to Site Investigation and Pile Design for Offshore Wind Farms

A CPT-Based Design Framework for Uplifted Open-Ended Piles Installed in Spatially Variable Sandy Soils. II: Implications to Site Investigation and Pile Design for Offshore Wind Farms