Structural Requirements Research Articles

BIM-based Rebar Modeling for Variable Section L-shaped Columns

Building Information Modeling (BIM), as a kind of digital means applied in the process of building design, construction and management, has been widely used in all aspects of construction engineering. However, the application of BIM in the field of steel reinforcement engineering, due to the wide variety of rebar and complex shapes in the plan construction drawings, the rebar modeling is inefficient and prone to errors, and the traditional plug-in for standard column models is usually difficult to cope with the demand for modeling rebar of complex components such as variable cross-section shaped columns. Therefore, with the help of the program and algorithms to create a BIM model of rebar can reduce the occurrence of the above problems. This paper mainly uses Revit secondary development technology, with the help of C# programming language to develop a program for automatic generation of reinforcing steel BIM model for variable section L-shaped columns. The program combines the structural requirements of reinforcement in the building code and standard drawings, identifies the key nodes of the shaped column model, calculates the coordinate points of the reinforcement, and carries out targeted algorithmic processing for the arrangement of reinforcement in the complex variable cross-section area of the upper and lower columns to complete the creation of the BIM model of reinforcement in the shaped column. The development of this program provides a variety of efficient ideas for the creation of complex structural reinforcement for other shaped columns, which helps to save the time of designers to create BIM models, ensures the geometric accuracy of the reinforcement model, and helps to promote the informatization and intelligentization of the construction of reinforced concrete structures.

ROMANIA'S JOB MARKET: TRENDS IN JOB OPPORTUNITIES, EDUCATIONAL REQUIREMENTS AND INDUSTRY NEEDS

The supply of labor is the primary asset of the economy and the ability to adjust to the challenges of advancing technologies. This study looked into 9,768 job postings for 29,000 open positions in 3,451 companies. The results reveal that the sectoral distribution of job opportunities is headed by Retail & Commerce, with 27.13% of all open positions, underpinning the consumer-driven economy of Romania. The analysis reveals a relatively low level of part-time and project-based open positions and internships, which are even less so, signifying a low requirement for alternative employment structures. More interestingly, educational requirements represent a wide spectrum of opportunities for candidates with varied qualifications. Graduates represent 45.48% of open positions, underlining the demand for higher education in technical and professional areas. However, students have a fair share of accessible opportunities, at 27.85%, and 54.89% for candidates with no qualifications, reflecting the reality that many industries will value experience and on-site learning more than formal qualification.

Lonidamine, a Novel Modulator for the BvgAS System of Bordetella Species.

The Gram-negative bacteria Bordetella pertussis, B. parapertussis, and B. bronchiseptica cause respiratory diseases in various mammals. They share the BvgAS two-component system, which regulates the phenotypic conversion between the virulent Bvg+ and avirulent Bvg- phases. In the BvgAS system, the sensor kinase BvgS senses environmental cues and transduces a phosphorelay signal to the response regulator BvgA, which leads to the expression of Bvg+ phase-specific genes, including virulence factor genes. Bacteria grown at 37°C exhibit the Bvg+ phenotype. In contrast, at lower than 26°C or in the presence of modulators, such as MgSO4 and nicotinic acid, the BvgAS system is inactivated, leading bacteria to the avirulent Bvg- phase. Therefore, effective modulators are expected to provide a therapeutic measure for Bordetella infection; however, no such modulators are currently available, and the mechanism by which modulators inactivate the BvgAS system is poorly understood. In the present study, we identified lonidamine as a novel modulator after screening an FDA-approved drug library using bacterial reporter systems with the Bvg+-specific and Bvg--specific promoters. Lonidamine directly bound to the VFT2 domain of BvgS and inactivated the BvgAS system at concentrations as low as 50 nM, which was at least 2000- to 20,000-fold lower than the effective concentrations of known modulators. Lonidamine significantly reduced the adherence of B. pertussis to cultured cells but unexpectedly exacerbated bacterial colonization of the mouse nasal septum. These results provide insights into the structural requirements for BvgAS modulators and the role of Bvg phenotypes in the establishment of infection.

Sustainability of California's Whole Person Care pilots integrating medical and social services for Medicaid enrollees via newly developed Medicaid benefits.

To assess multi-level factors influencing the sustainability of 26 social care pilots integrating medical and social services for Medicaid enrollees across California in newly developed Medicaid benefits. This qualitative study assessed the sustainability of Whole Person Care (WPC) pilots implemented between 2016 and 2021. Pilots (n = 26) represented a majority of counties in California. Primary qualitative data were collected between June and August 2021 and included 58 hour-long, semi-structured individual and group interviews with administrators, middle managers, and frontline case management staff representing all WPC pilots. We used hybrid inductive-deductive thematic analysis to identify and analyze patterns, and outliers, in factors influencing sustainment. Deductive codes included established implementation science factors influencing the sustainability of new programs (e.g., innovation characteristics, capacity, processes and interactions, and context). Of 26 WPC pilots, 22 pilots sustained WPC by contracting with Medicaid managed care plans to provide services as part of newly developed Medicaid benefits. Three pilots chose not to sustain before the pilot period ended and one pilot decided not to sustain following completion of the full pilot. Factors influencing sustainability included: (1) program adaptability and flexibility; (2) funding structure and reimbursement requirements; (3) shared leadership with managed care plans; and (4) whether pilots chose to build out program infrastructure internally or contracted out core components to partner organizations. Many pilots, particularly those in rural areas, indicated that system and policy changes introduced as part of transitioning pilot services into Medicaid benefits reduced the sustainability of WPC for participating providers. Multi-level factors including program adaptability, funding, leadership, and capacity to build out infrastructure influenced the sustainability of WPC pilots. These findings have significant implications for health equity as equitable distribution of services, resources, and benefits from these programs can be supported through sustained implementation over time.

Modal analysis and optimization design of modular steel structures used in construction

In order to improve the stability and reliability of modular steel structures and reduce design redundancy, a multi-objective optimization study was conducted based on modal analysis. The finite element method was used to obtain the natural frequencies and modes under actual constraint conditions through ANSYS. The first-order natural frequency was used as a constraint condition to rationally configure the dimensions of the modular steel structure, and lightweight design was carried out based on the response surface method. In order to meet the overall structural stiffness requirements, the weight of the structure was minimized as much as possible. The finite element analysis and modal verification of the optimized model were carried out to verify the optimization results that meet the design requirements. The results show that the weight of the model was reduced by 5.36 %, and the increase in the first-order natural frequency was 20.14 %. After analyzing and verifying the modal vibration mode structure, it was found that the optimized modal vibration mode structure could still meet the mechanical performance requirements, providing an important reference for research in the field of building engineering.

Modal analysis and lightweight design of key components of the anchor windlass

To improve the rationality of the mechanical design of traditional ship anchor windlass, based on modal analysis, lightweight research was conducted on key components. Taking the first-order natural frequency as the constraint condition, topological optimization design was carried out for the base, and size optimization design based on the response surface algorithm was carried out for the anchor chain wheel. On the premise of meeting the overall structural strength and stiffness requirements of the anchor windlass, its weight was reduced as much as possible. Through the finite element analysis and strength check of the optimized model, it was verified that the optimization results met the design requirements. The research shows that the weight reduction rate of the base reached 13.34 %, and the weight reduction rate of the anchor sprocket reached 10.5 %. After analysis and verification, the optimized structure can still meet the overall mechanical performance of the anchor windlass and achieve the expected design goal, which also provides an important reference for the structural optimization and lightweight research of other ship equipment.

Modified Delphi Study to Establish Consensus About Child Neurology Residency Education: Next-Gen Training.

Rapid advances in diagnostics and treatments are shifting child neurology practice, but child neurology training requirements have been much slower to change. Previous literature confirms strong support for modernization, but no formal consensus exists regarding maintaining or changing training. We aimed to develop a holistic consensus regarding the optimal training pathway and requirements using a modified Delphi process. The authors invited 48 child neurologists as panelists, intentionally selecting to represent the diverse geography, practice type, subspecialties, and other demographics of child neurologists practicing in the United States. Panelists participated in an anonymized modified Delphi study with 4 rounds evaluating statements regarding current training requirements, core rotation durations, and mandatory subspecialty rotations with the option to agree or disagree. Statements were derived from current Accreditation Council of Graduate Medical Education, American Board of Psychiatry and Neurology, and American Board of Pediatrics requirements for child neurology training and recent literature. Statements that did not reach a predefined level of consensus (≥75% agreement or disagreement on a 7-point Likert scale) were re-queried or modified for subsequent rounds. Panelists had access to all previous anonymized results and comments. The final modifications were presented in round 4 as a comprehensive training proposal. Twenty-seven panelists agreed to participate, with most completing all 4 rounds. In round 1, consensus was reached on 45 of 118 (38%) items; round 2, 28 of 87 (32%); round 3, 16 of 25 (64%); and round 4, 1 of 1 (100%). There was consensus regarding the age scope of practice and certain subspecialties that should be required, but no initial consensus regarding time-based requirements. By round 4, consensus emerged for the following rotations-months: neonatal and pediatric intensive care-4, adolescent medicine-0.5, emergency medicine-1.5, inpatient pediatrics-3, outpatient pediatrics-3.5, inpatient child neurology-9.5, outpatient child neurology-6, inpatient adult neurology-3, outpatient adult neurology-2, genetics-2, EEG/neurophysiology-2, neuroimaging-1, child psychiatry-1, and electives-7.5. The consensus schedule consists of 46.5 total months of requirements. This study suggests that, despite diverging views prevalent among child neurologists, a diverse panel can, through a multiround Delphi process, arrive at consensus regarding many core features of the child neurology training structure and certification requirements.

Insights through molecular modeling into the structural requirement of Phenyl(6-phenylpyrazin-2-yl)methanone derivatives as aldose reductase inhibitors

Aldose reductase, play an important role in the pathogenesis of diabetic complications such as neuropathy, nephropathy and retinopathy. Therefore design of aldose reductase inhibitors has received considerable attention. In the present study molecular insights were explored through docking and QSAR. The quantification of the structural features of Phenyl(6-phenylpyrazin-2-yl)methanone analogs inferred that atomic Senderson electronegativity, van der Waals volume and charge distribution on the molecule are decisive for the aldose reductase inhibitory activity. Moreover, docking study depicted that benzonoid system of scaffold is crucial for - interaction with the side chain of key aromatic amino acids i.e. TRP111 and TRP20. These structural insights might provide significant roadmap for continuing search of potential ARIs prior to synthesis.

Development and experimental study of a replaceable double stage coupling beam damper

A double stage coupling beam damper (DSCBD) was proposed and tested in this paper. The DSCBD comprises a viscoelastic damper and a metallic damper connected in series. Deformation of the DSCBD in the first stage was concentrated on the viscoelastic damper, which provided initial stiffness and energy dissipation capacity. With the increase in displacement and the initiation of the second stage, the deformation of the viscoelastic damper was constrained by the limiting mechanism and triggered the deformation concentrating in the metallic damper. These further increased the stiffness and energy dissipation capacity and the DSCBD exhibits the double stage behavior. The DSCBD proposed in this paper can simultaneously satisfy the seismic requirements of the main structure under different levels of seismic excitation, without installing different types of traditional dampers to achieve the same effect. A performance-based design method was proposed. Two full-scale DSCBD specimens were subjected to quasi-static multi-stage cyclic loading tests to investigate the effects of different aspect ratios. The test results showed that DSCBD with an aspect ratio of 3.2 exhibited ideal shear failure mode, and the minimum equivalent viscoelastic damping ratio in the second stage was 22.58 %, while the DSCBD with an aspect ratio of 4.4 exhibited unexpected bending failure mode, and the maximum equivalent viscoelastic damping ratio in the second stage was 19.42 %. In addition, the DSCBD with an aspect ratio of 3.2 showed better low-cycle fatigue capacity, whose degradation of bearing and energy dissipation capacities can be controlled within 5 % after 30 additional loading cycles. The accuracy and the correction scheme of the design method were verified by the test results.

Formulating standard requirements for search web-based interfaces of e-catalogs

Within the framework of R&D project “Information support of research by scientists and specialists on the basis of RNPLST Open Archive as the system of scientific knowledge aggregation”, the RNPLS&T carries on the analysis of general characteristics and features of and defining standard requirements for the LIS search interfaces. The author attempts to develop the array of the requirements for modern web-based interfaces of e-catalogs, to classify and formulate them more specifically, and to substantiate these requirements. She proposes the following classification of the requirements: general requirements, requirements for search functionality structure, requirement for content enrichment, requirement for the system of search user support, requirements for applying recommendation system and existence of auxiliary user support. The author also suggests the ways to improve search interfaces of e-catalogs, in particular, to unify and differentiate search instruments, to obtain additional search options, to implement different types of user support more intensively, and to create effective multifunctional recommender systems. The proposed recommendations may be used for search interfaces of library information systems.

Metamodel-based Hybrid Parametric Optimization with Static Prototype Validation for a Six-Axle Wheel Load Cell Design

The accurate measurement of forces and torques acting on a vehicle’s chassis, originating from wheel-pavement interactions, is essential for optimizing suspension systems, axles, and other structural components. A critical challenge in optimizing wheel load cell (WLC) design is to enhance sensitivity without compromising mechanical robustness. To address this question, this study developed a six-axis load cell designed to decouple force and torque measurements, achieving high sensitivity and reliability. The objective was to design an optimized WLC for multi-axis force measurement by maximizing sensitivity through a metamodel-based hybrid optimization framework. The methodology began with a fractional factorial Design of Experiments (DOE) to identify key parameters affecting load cell sensitivity and to define the optimization search space. This was followed by a dual-step parametric optimization process, utilizing the finite element method (FEM) to evaluate load cell performance and an inner-point optimization algorithm for convergence. After completing the DOE and FEM stages, the load cell was physically constructed and calibrated using a universal testing machine MTS 810, where experimental data closely matched simulation results, validating the design’s effectiveness. The main findings indicate that the optimized load cell can reliably measure six components, with a sensitivity increase of 14% compared to conventional designs. Numerical results from FEM analyses showed stress levels at 215 MPa, displacements around 0.16 mm, and a first-mode vibration frequency of 1351 Hz, meeting all structural integrity and performance requirements. Calibration confirmed minimal cross-talk effects, supporting the robustness of the final design. The developed load cell met optimal design criteria, showing substantial improvements in sensitivity and accuracy over existing designs, with potential applications in automotive, aerospace, and engineering testing.

Optimization schemes on manifolds for structured matrices with fixed eigenvalues

AbstractSeveral manifold optimization schemes are presented and analyzed for solving a specialized inverse structured symmetric matrix problem with prescribed spectrum. Some entries in the desired matrix are assigned in advance and cannot be altered. The rest of the entries are free, some of them preferably away from zero. The reconstructed matrix must satisfy these requirements and its eigenvalues must be the given ones. This inverse eigenvalue problem is related to the problem of determining the graph, with weights on the undirected edges, of the matrix associated with its sparse pattern. Our optimization schemes are based on considering the eigenvector matrix as the only unknown and iteratively moving on the manifold of orthogonal matrices, forcing the additional structural requirements through a change of variables and a convenient differentiable objective function in the space of square matrices. We propose Riemannian gradient-type methods combined with two different well-known retractions, and with two well-known constrained optimization strategies: penalization and augmented Lagrangian. We also present a block alternating technique that takes advantage of a proper separation of variables. Convergence properties of the penalty alternating approach are established. Finally, we present initial numerical results to demonstrate the effectiveness of our proposals.

Research on the Influence of Ceramic Diameter on Anti-penetration Performance under Constrained Conditions

Abstract Three dimensional constraints can improve the anti-penetration performance of ceramics. According to the actual usage requirements of armor structures, a three-dimensional constrained ceramic composite structure was designed. The influence of ceramic diameter on the penetration resistance of composite structures under three-dimensional constraint conditions was studied by combining experimental and numerical simulation methods. The research results indicate that during the penetration process of long rod projectiles, circumferential constraints can effectively suppress the circumferential fracture of ceramics, while frontal constraints can suppress the fracture of ceramics along the direction of projectile incidence. Three dimensional constraints can improve the penetration resistance of ceramics. For long rod projectiles, the confinement performance of the circumferential structure on ceramics can be fully utilized when the ceramic diameter is three times the diameter of the projectile. Circumferential constraints not only suppress ceramic fragmentation, but also enhance the interaction force between ceramics and projectiles.

Full-scale test analysis of impact resistance of prestressed reinforced concrete containment

Abstract The failure mechanism of prestressed reinforced concrete structures under high-speed impact loads has always been a frontier research hotspot. In this experiment, the relationship between the impact force and time of the prestressed reinforced concrete structure under high-speed impact load was studied by rocket skid test using the real “Turbojet-6” engine, which provided data support for the subsequent analysis of the nonlinear dynamic response of the structure. The test results show that prestressing can enhance the local penetration resistance of concrete containment to a certain extent. Under the impact of the “Turbojet-6” engine, the prestressed reinforced concrete containment can keep the concrete structure intact, the steel lining unyielding, and the steel bar unbroken, which meets the structural integrity requirements.

DESIGN AND STATIC ANALYSIS OF PRISMATIC PRESSURE VESSELS ACCORDING TO TS 13445-3 STANDARD

The focus of the presented work is on the design and analysis of prismatic pressure vessels. Engineering calculations, design parameters and performance criteria of pressure vessels are available in the literature in detail, but there are deficiencies in the evaluation of the manufacturing processes of prismatic pressure vessels and the mathematical formulae required by these processes in the light of standards. In this context, it was investigated how a special prismatic pressure vessel, a square profile hyperbaric oxygen chamber, could be optimised in terms of structural strength, stress distribution and safety requirements. The material selection and design of such a chamber has been evaluated using DBA and DBF methods. The performance of the prismatic hyperbaric oxygen chamber in current applications is explained, supported by various engineering analyses and simulations. It was observed that the cabin designed in accordance with TS 13445-3 standards is 2 times safe under operating conditions and the amount of displacement is commercially acceptable. It is shown with SolidWorks analysis.

Design and simulation analysis of a two-dimensional extended array structure

Abstract A compact and two-dimensional expandable extended array structure was designed to meet the electrical and structural compatibility requirements of a certain type of equipment. The transition from the distance between the RF component side RF channels A × B (mm) to the distance between the antenna array units a × b (mm) was achieved. The structural mechanical performance simulation was conducted. It was found that the deformation in the connector insertion direction was significant, which affected the reliability of the RF connection. Based on the simulation results, the original structural scheme was optimized and further improved to enhance the assembly, maintenance, and interchangeability of the extended array. The maximum structural deformation in the insertion direction of the RF connector was 0.19mm, which was reduced by 0.2mm compared to the previous optimized scheme with a structural deformation of 0.39mm. The large deformation area was significantly reduced. The stiffness of the structure was significantly improved, meeting the reliability requirements of multi-channel module RF blind insertion.

Comparative study of earthquake – resistant building design according to SNI 03-1726-2019 in Jakarta and Aceh regions

Abstract Indonesia’s unique geological setting necessitates region-specific approaches to earthquake-resistant building design. This study investigates the comparative structural behavior and design requirements of buildings in Jakarta and Aceh, two regions with contrasting seismic hazards, adhering to the Indonesian seismic code SNI 03-1726-2019. Utilizing ETABS software and the response spectrum method, the research reveals that structures in Aceh, due to the heightened seismic risk, demand larger dimensions (up to 40% increase in column size) compared to those in Jakarta. The analysis also uncovers similar patterns of horizontal and vertical irregularity in both regions. The base shear, a crucial indicator of seismic demand, is notably higher in Aceh (742,781.6 kN) than in Jakarta (588,980.6 kN). Additionally, roof displacement values exhibit variations between the two regions, with Jakarta recording 31.895 mm and 61.518 mm, and Aceh showing 30.542 mm and 56.936 mm. This study shows that regions with higher seismic acceleration necessitate greater building capacity to withstand the increased seismic forces. The research concludes that effective earthquake-resistant design must be tailored to the specific seismic context of each region, ensuring the safety and resilience of buildings across Indonesia.

Vascular rehabilitation for patients with peripheral arterial occlusive disease

Compared to patients with coronary heart disease, patients with PAD have a poorer attitude towards general practitioners with regard to the frequency of prescribing rehabilitative measures and controlling risk factors. The patients themselves do not perceive the increased cardiovascular risk and thus the need for lifestyle changes and compliance to the same extent as patients with coronary heart disease.The "Rehabilitation clinic with vascular expertise" certificate defines the criteria for fulfilling the specific structural and process requirements for vascular medicine.Due to the paradigm shift and the increasing importance of conservative therapy for patients with intermittent claudication, vascular rehabilitation can be the start of or support for the implementation of conservative therapy and thus ensure long-term patient compliance with regard to the implementation of drug therapy, lifestyle changes and the sustainability of gait training. For hospitalized patients, vascular rehabilitation closes the gap to more sustainable aftercare.Increasing demand will promote the development of vascular medical rehabilitation and increase awareness on the part of payers. This process is being scientifically monitored.The goal should be a care structure for patients with PAD that is regulated on an outpatient basis as part of a separate or adapted DMP program, that includes the quality standards of the "Interdisciplinary Vascular Centers" on an inpatient basis and that includes vascular medical rehabilitation with subordinate vascular sports groups.From the point of view of rehabilitation, the aim is for vascular rehabilitation to be recognized as an independent specialist area by the payers.

Optimizing engineering potential in sustainable structural concrete brick utilizing pond ash and unwashed recycled glass sand integration

The Australian construction sector faces a dual challenge of high demand for concrete bricks and the need for sustainable materials. This research investigates eco-friendly structural concrete brick formulations, incorporating pond ash and unwashed recycled glass sand. It aims to provide scientific evidence on their engineering performance as per AS/NZS 4455.1:2008 standard, thermal insulation, and fire resistance properties. Additionally, microstructural, chemical, and pore-structure analyses are carried out to gain insights into the reaction mechanisms and the evolution of their properties. Findings indicate that bricks with 15% pond ash and 20% unwashed glass sand meet structural requirements with compression strength of 29.63MPa at 28 days. Enhanced thermal insulation is observed due to the lower densities of pond ash and glass sand. After a 2-hour exposure to elevated temperatures, the unexposed surface of these bricks remains below 180°C, satisfying fire resistance criteria for wall elements. However, microstructure and chemistry analyses suggest lower compression and tensile strength comparable conventional bricks because of low reactivity of the pond ash and the smooth surface of the glass sand.

3D and 2D-QSAR Studies on Natural Flavonoids for Nitric Oxide Production Inhibitory Activity

Background: Nitric oxide (NO), an important second messenger molecule, regulates numerous physiological responses, while excessive NO generates negative effects on the circulatory, nervous and immune systems. Recently, some natural flavonoids were reported to possess the capability of inhibiting LPS-induced NO production. To fully understand the nature of their own NO inhibitory activity, it is necessary to address the structural requirements of flavonoids as NO inhibitors. Objective: The objective of this work was to develop efficient QSAR models for predicting the NOinhibitory activity of new flavonoids and improving insights into the critical properties of the chemical structures that were required for the ideal NO production inhibitory activities. Methods: To provide insights into the structural basis of flavonoids as NO inhibitors, 3D quantitative structure-activity relationship (3D-QSAR) and 2D-QSAR models were developed on a dataset of 55 flavonoids using comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA) and hologram quantitative structure-activity relationship (HQSAR) approaches. Results: The statistically significant models for CoMFA, CoMSIA and HQSAR resulted in crossvalidated coefficient (q2) values of 0.523, 0.572 and 0.639, non-cross-validated coefficient (r2) values of 0.793, 0.828 and 0.852, respectively. The robustness of these models was further affirmed using a test set of 18 compounds, which resulted in predictive correlation coefficients (r2 pred) of 0.968, 0.954 and 0.906. Furthermore, the models-derived contour maps were appraised for activity trends for the molecules analyzed. Conclusion: The 3D and 2D-QSAR models constructed in this paper were efficient in estimating the NO inhibitory activities of flavonoids and facilitating the design of flavonoid-derived NO production inhibitors.