Open Web Research Articles

The magnitude of stress concentration of I-beam with web opening because of lateral-torsional buckling effects

PurposeIt is generally known that the perforated section such as the castellated section is good to sustain distributed loads but inadequate to sustain highly concentrated loads. Therefore, it is possible to design the opening in a different arrangement of web opening to achieve section efficiency, thus improving the strength and torsional behaviour of the section with web opening. This study aims to focus on the finite element analysis of I-beam with and without openings in steel section dominated to lateral-torsional buckling behaviour.Design/methodology/approachIn this work, the analysis of different sizes, shapes and arrangements of web opening is performed by using LUSAS application to conduct numerical analysis on lateral-torsional buckling behaviour. This involves three diameter sizes of web opening, five types of opening shapes and two criteria of the model.FindingsThe section with c-hexagon web opening was placed about 200-mm centre to centre and 100-mm edge distance, contribute to 7.26% increase of buckling capacity. For the section with 150-mm centre to centre and 50-mm edge distance, the occurrence of local buckling contributes to decrease of lateral buckling section capacity to 19.943 kNm, where pure lateral-torsional buckling mostly occurred because of prevented section. Besides that, the web opening diameter was also analysed. The web crippling was observed because of the increase of opening diameter from 0.67 to 0.80 D.Originality/valueThis contributes to a decrease in buckling capacity as figured in the contour of the deformed shape. For Model 1, an increase of buckling capacity (31.46%) is observed when the opening diameter are changed from 0.67 to 0.80 D.

The analysis of web opening configuration on cold-formed steel hat purlin under torsion behaviour

PurposeCold-formed steel has been used extensively as secondary elements such as purlins and girts in building frames. Purlin is critical to the structure of the roof because it supports the weight of the roof deck and aids to make the entire roof structure more rigid. Furthermore, cold-formed steel purlin is a replacement for wood purlin because steel purlins are light weight and more economical. Hence, the purpose of this study to investigate the effect of opening due to torsion behaviour.Design/methodology/approachThis analysis used cold-formed steel hat purlin with and without openings (WOs) under different opening shape, location and spacing by using finite element LUSAS software.FindingsThe finite element results showed that purlin with openings had higher angle of rotation than section WO, with a percentage difference of not more than 6%. When the opening was located at mid-span, the angle of rotation reduced. Angle of rotation increased when the opening spacing increased. Number of openings also affected the torsional behaviour of the purlin. Five opening shapes, which were circle, diamond, C-hexagon, square and elongated circle, were studied. Among all the shapes, purlin with diamond opening was more resistance to torsion.Originality/valueThe use of cold-formed steel section with web openings (rectangular or circular) is a practical solution when it is required to pass service ducts through the structural member. However, the presence of opening gives minor effect on the structural behaviour of cold-formed steel hat purlin.

Overcoming The Taxonomic Impediment: An Action Plan For India

Insect taxonomy in India has been on a terminal decline and the unknown and undocumented insects of India face the threat of extinction before they are formally described due to climate change, habitat destruction and other anthropogenic factors. Ways to overcome the so called ‘Taxonomic impediment’, loosely defined as the lack of experts and funds and other resources for taxonomic research, are briefly discussed in the Indian context. A combination of concise morphological descriptions, high resolution digital imaging and open access web publishing with at least minimum molecular characterization (COI sequences) appears to be an ideal way to promote fast track documentation of Indian insects. Needless to add, increased funding and opportunities for insect taxonomy is the foremost requirement to further the cause of insect taxonomy in India. For this, insect taxonomic services should be recognized as a major input in agricultural pest management technology by ICAR and state agricultural universities.

Mechanism of shear strengthening for RC beam by drilling web openings based on experiment and 3D RBSM analysis

In practice, web openings are usually drilled in reinforced concrete (RC) beams to accommodate pipes and cable installations. But introducing web openings always causes shear degradation of RC beams. This study aims to establish a rational position design of multiple small web openings, which can improve the shear behavior of RC beams, by controlling the path of critical diagonal crack. Three-point bending tests on four RC beams without and with web openings (shear span depth ratio: 2.59 and 3.56) were firstly carried out to evaluate the strengthening effect attributed to the proposed placement of web openings. Besides, the Three Dimensional Rigid-Body-Spring Method (3D RBSM), a discrete numerical methodology, was applied to simulate the test process, and the strengthening effect due to the placement of web openings was parametrically investigated. Finally, the decoupling of shear components (beam and arch actions) was conducted to comprehensively understand the shear strengthening mechanism due to drilling web openings, by using RBSM-based methodology. The test and numerical results confirmed that the proposed position design of web openings could evidently improve the shear strength and deformation ability of RC beams, because the multiple web openings could increase the angle of critical diagonal crack, by predetermining it propagation path. Moreover, it was clarified that the strengthening mechanism of shear behavior owing to web opening setting was dependent on the more dramatic development of arch action with the increasing angle of critical diagonal crack. The present paper provided a rational design to solve the problem of shear degradation caused by small web openings in the field of concrete member design, and proved a possibility to strengthen the shear behavior of existing concrete beams by drilling web openings.

Experimental and analytical investigation on effect of openings in behavior of reinforced concrete deep beam and enhanced by CFRP laminates

This work studies the potential of producing web openings within the shear span for the reinforced concrete (RC) deep beams. Carbon fiber reinforced polymer (CFRP) laminates are used to improve the shear strength. 13 specimens with dimensions of 120, 750, and 1800 mm are prepared for the tests. Shapes of the web openings are square and circular with diameter of 230, 300, and 370 mm. Their locations are in the center, upper and lower of the shear span. Three angles for wrapping 0°, 45°, and 90° are used to strengthen the beams with circular openings. The shear strength of RC deep beams decreased in the range of 22–74 % depending on the diameter, location, and shape of the openings. While CFRP improved the shear strength, stiffness and toughness in about 17–48 %, 0.7–17 % and 4–20 % respectively. The previous percentages depended on size of openings and the orientation of CFRP laminates in RC deep beams with circular openings. The laminates of CFRP are able to repair and restore the bearing capacity of beams by approximately 100 % of the same beams before they failed. On the other hand, Strut and Tie method established to estimate the maximum strength of the RC deep beams and it results that the theoretical method succeeded in guessing the practical results.

Bending performance of dapped-end beams having web opening: Experimental and numerical investigation

Reinforced concrete dapped-end (purlin) beams are frequently used in prefabricated industrial structures. The main task of these beams is to safely carry the loads on the roof. Considering the number of these purlin beams in industrial buildings, it is extremely important for manufacturers to product these beams with less concrete without reducing the load carrying capacity. Since these purlin beams are under the effect of bending and shear forces, controlled creating openings in beam span can have significant economic benefits for the manufacturer. Therefore especially economic design perspective, it is so crucial to determine the amount of openings that will not cause a significant change in the bending behavior. In this study, the behavior of dapped-end purlins with openings was experimentally and numerically investigated. In the experimental step, seven purlin beams having different opening configurations were tested under four-point loading to investigate the openings effects on beam structural behavior. In this step opening length to total length varying between 0.075 and 0.325 was selected as a main parameter. After test, the numerical models were created and verified using experimental findings. After this step, in the parametric study part of the paper, the effects of shear span, depth of the opening and length of opening and different opening configurations (such as segmentation) which were not tested in experiments, were examined. The experimental outcomes revealed that increases in the opening did not provide a significant effect on the load capacity. This can be explained by the fact that the openings are in the bending region. The numerical findings showed that increasing shear span to depth ratio (av/d) ratio did not change rigidity but decreased the load capacity. However, no effect was observed on the opening height provided that it is at least as far away from the upper and lower longitudinal reinforcements bars as the concrete-cover margin. On the other hand, increasing opening/purlin length (especially higher than 0.375) reduces the capacity. However, segmented openings (multiple openings instead of single whole openings) did not reduce capacity even if total opening/purlin length was 0.525.

Moment gradient factor for steel I-beams with sinusoidal web openings

The moment gradient factor is an important parameter to be considered in the design of beams subjected to failure by Lateral-torsional Buckling. The analytical formulation to obtain the critical moment for the LTB is based on the assumption of applying a constant bending moment along the free span of the structural element. This loading situation is not usual in engineering projects, so it is necessary to correct the value of the critical moment according to the different loading situations that can be found in practical cases. Thus, many design codes worldwide assign values to perform this correction. The moment gradient factor, Cb, is determined by comparing the elastic critical moment of a beam subject to varying moment condition with that subject to a constant moment condition. When considering beams with web openings, there are currently no recommendations or proposals for calculating the moment gradient factor, considering loads applied outside the shear center. There are also no explicit recommendations in standards regarding the design of this type of structure. Recent research deals with the influence of cellular beam parameters on the moment gradient factor; however, they do not present explicit proposals for its calculation in structures of this nature. The research scenario in the literature becomes even more scarce when considering beams with sinusoidal web openings. Thus, the paper investigates this for a wide range of I-beams with openings, with the goal of analyzing the influence of the openings on the Cb, as well as proposing formulae for usual design situations. The proposals were obtained through prediction models derived from an extensive parametric study using the ABAQUS finite element software, in which 34,020 models were developed.

Flexural behavior of steel–concrete ultra-shallow floor beams (USFBs) with precast hollow-core slabs

This paper aims to predict the flexural behavior of steel–concrete composite ultra-shallow floor beams (USFBs) with precast hollow-core slab (PCHCS). A finite element model based on tests is developed. A parametric study is conducted, and the influence of the geometric parameters is discussed. The finite element results were compared with stress block analysis. It was concluded that the modeling with two symmetry planes offered better computational cost, and the flexural behavior of steel concrete USFBs was sensitive to dilation angles. From the parametric study, the models without steel tie bar through the web openings showed lower bending capacity. The variation of the reinforcement ratio of the concrete topping contributed to the cracking control. The plastic neutral axis position was measured, considering the mid-span vertical displacement at 10 mm, 50 mm and 100 mm. From the stress distribution it was observed that to define the resisting moment, the P.N.A. closest to the top tee can be considered. The theoretical model underestimated the resistance of USFBs with PCHCS.

Profiling the vendors of COVID‐19 related product on the Darknet: An observational study

BackgroundIn a time of unprecedented global change, the COVID-19 pandemic has led to a surge in demand of COVID-19 vaccines and related certifications. Mainly due to supply shortages, counterfeit vaccines, fake documentation, and alleged cures to illegal portfolios, have been offered on darkweb marketplaces (DWMs) with important public health consequences. We aimed to profile key DWMs and vendors by presenting some in-depth case studies. MethodsA non-systematic search for COVID-19 products was performed across 118 DWMs. Levels of activity, credibility, content, COVID-19 product listings, privacy protocols were among the features retrieved. Open web fora and other open web sources were also considered for further analysis of both functional and non functional DWMs. Collected data refers to the period between January 2020 and October 2021. ResultsA total of 42 relevant listings sold by 24 vendors across eight DWMs were identified. Four of these markets were active and well-established at the time of the study with good levels of credibility. COVID-19 products were listed alongside other marketplace content. Vendors had a trusted profile, communicated in English language and accepted payments in cryptocurrencies (Monero or Bitcoin). Their geographical location included the USA, Asia and Europe. While COVID-19 related goods were mostly available for regional supply, other listings were also shipped worldwide. InterpretationFindings emerging from this study rise important questions about the health safety of certain DWMs activities and encourage the development of targeted interventions to overcome such new and rapidly expanding public health threats. FundingCovSaf, National Research centre on Privacy, Harm Reduction and Adversarial Influence Online (REPHRAIN), Commonwealth Fund.

Hacia la madurez de los portales de datos públicos abiertos en el sector público. Un análisis comparado del nivel local de gobierno en España

Open public data portals have become one of the main technologies of public administrations for the exercise of transparency, accountability, citizen participation and co-production of public services. Few empirical studies have analyzed on a large scale the use of these platforms considering their multidimensional nature. This research offers an empirical analysis of how these technological artifacts are being used at the Spanish local level. An observation of 66 open public data web portals enabled by Spanish municipalities with more than 50,000 inhabitants has been carried out through a framework of indicators and dimensions based on previous literature. The results, derived from a descriptive statistical analysis of the state of evolution of the portals observed, show a certain preference for a technical development linked to transparency, as opposed to a social and reuse dimension. The implications of this study highlight an incipient transformation of local public administration, whereas the paradigm of smart public management -more participative and collaborative- has not yet fully accomplished. Also, this study provides a basis for the development of future research that requires further study of the dimensions of citizen participation and co-production by the advent of open public data.

Prediction of Continuous Rainfall-Runoff Scenarios for Snow-Fed Watershed of Himachal Pradesh, India using Geographical Information System GIS based on Hydrological Modelling

Rainfall runoff modeling is one of the most complex hydrological modeling due to the involvement of different watershed physical parameters. It is essential for the analysis of watershed hydrological response towards the received precipitation under the influence of watershed variables. As it is a replica of watershed hydrological response, Rainfall-Runoff modeling is essential to evaluate the general characteristics of total surface runoff at catchment’s outlet. The main objective of this study was prediction of rainfall runoff using Hydrologic Engineering Center-Hydrologic Modeling System [HEC-HMS] model for Rampur watershed which was covered in Kullu and Shimla districts situated at Upper Sutlej sub-basin of Himachal Pradesh, India. Geo-spatial data of Digital Elevation Model,LandUse-LandCover (LU-LC) map, Soil map and Hydro-meteorological data of rainfall were collected from different open source web portals to utilise as input parameters for modeling. Soil Conservation Service-Curve Number (SCS-CN) for precipitation loss modeling, Soil Conservation Service–Dimensionless Unit Hydrograph [SCS-UH] for transform modeling, Muskingum method for Runoff routing were used as input parameters of respective components of HEC-HMS model. This article proposes a methodology for generating hourly rainfall data from daily rainfall data using Intensity-Duration-Frequencycurves in Meteorological model of HMS. The simulation results of runoff with 5 different return period scenarios are follows the return period frequency tendency, such as 1000 year return period runoff peak delivers 4729.5 m3/s, 500 year return period delivers a peak runoff of 4263.9 m3/s, 100 year return period gives a peak runoff of 3196.5 m3/s, 50 year return period runoff deliver 2745.3 m3/s and 10 year return period deliver 953.7 m3/s runoff at the outlet of Rampur watershed.

Sanare: Pluggable Intrusion Recovery for Web Applications

Web applications are exposed to many threats and, despite the best defensive efforts, are often successfully attacked. Reverting the effects of an attack on the state of such an application requires a profound knowledge about the application, to understand what data did the attack corrupt. Furthermore, it requires knowing what steps are needed to revert the effects without modifying legitimate data created by legitimate users. Existing intrusion recovery systems are capable of reverting the effects of the attack but they require modifications to the source code of the application, which may be unpractical. We present <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Sanare</i> , a pluggable intrusion recovery system designed for web applications that use different data storage systems to keep their state. Sanare does not require any modification to the source code of the application or the web server. Instead, it uses a new deep learning scheme that we also introduce in the article, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Matchare</i> , that learns the matches between the HTTP requests and the database statements, file system operations, and web service requests that the HTTP requests caused. We evaluated Sanare with three open source web applications: WordPress, GitLab and ownCloud. In our experiments, Matchare achieved precision and recall higher than 97.5% with a performance overhead of less than 18% to the application.

Numerical Analysis of Castellated Beams with Various Web Openings for Marine Structures

Numerical Analysis of Castellated Beams with Various Web Openings for Marine Structures

Composite Beams with Web Openings Employing Alternative Layout of Shear Connectors

It is generally accepted that bearing systems consisting of composite elements, combining steel and concrete, are highly efficient. Nevertheless, the current economic situation generates continuous demand for more effective solutions. Hence, by the finite element model, this paper investigates an impact of alternative layout of shear connectors adopting a combination of continuous and discontinuous distribution. On the basis of numerical investigation, the study seeks an optimal layout of shear studs for simply supported composite beams under uniform static loading utilizing the same number of connectors for each span. The paper is divided into three parts. At first, investigated specimens are designed against European Standards and limitations according to the literature. This is followed by a parametric study using finite element models examining shear flow magnitudes at the steel-concrete interface and plastic strain evolution at the level of the bottom flange. Afterwards, the study reveals relations regarding the modified parameters and overall structural performance of composite girders. Despite that, the paper is unable to encompass the entire matter of issue but serves as a preliminary attempt to define a novel structural connection arrangement presenting more unit utilization of composite beams' resistance.

Consequences of Dissolution of Google’s Digital Advertising Business: The Remedy Requested in the Google Open Web Display Advertising Case

Consequences of Dissolution of Google’s Digital Advertising Business: The Remedy Requested in the Google Open Web Display Advertising Case

Rail Structure Interaction Analysis for Providing CWR on Un-Ballasted Multi-Span Open Web Steel Girder Bridge

Rail structure interaction (RSI) requires thorough study to understand the force transfer mechanism between the track and bridge components due to train vertical live loads, braking/traction loads and thermal loads accordingly. RSI analysis gives us an outline of the axial stress in rail, support reactions transferred to the bridge components and the relative displacement caused between the track and bridge. This paper investigates rail structure interaction analysis of unballasted multi-span steel through girder railway bridge carrying dedicated freight corridor (DFC) of 32.5t axle load. For this purpose, RSI analysis is performed as per the guidelines given in UIC774-3R [7] Code of Practice (International Union of Railways) for two different multi-span bridge with a span configuration of 7x63m and 6x48m respectively and the axial stress in rail, relative displacement between rail and bridge and support reactions transferred to the bridge components are calculated based on the span and stiffnesses of the bridges. From the analysis results, it shall be concluded whether to explore the possibility of providing a provision of continuous welded rail (CWR) on the bridge or to adopt switch expansion joints (SEJ) or other expansion devices accordingly.

Сравнение производительности алгоритмов классификации в рамках сетевой инфраструктуры

User authentication is now a standard procedure for access to corporate or public network infrastructure. The advantage of biometric authentication is the unique and unambiguous identification of an individual in the system. Supervised machine learning techniques were used to monitor user behavior to identify legitimate users. After testing all users using the classifiers, the verification rate was achieved at 98%. The results can be used in corporate projects and organizing contests. The work is conducted within the RemoteTopology platform. On the open web page, the user opens several RDP protocol sessions. VNC, Telnet, SSH. Session data is collected by the browser extension and transmitted to the database. In the second stage, an experiment was conducted to train and test each user using the classifiers defined above. If the characteristics that the user exhibits at the current time match those identified by the model training, the user continues to work, otherwise the system locks the user and requires re-authentication. The model must provide constant detection of user characteristics based on mouse dynamics. Characteristics are collected and packaged on the client side in a browser extension, then transmitted to the server and stored in a database. Each reliable action is then assigned a value, and a single block of work is not a single user. A single block is not an illegal or illegal user to block work. It can also be noted that for scenarios 1, 2 and 3 using the FAR, FRR, EER and ROC curve: scenario 1 had the lowest EER values: RF EER: 0.010%.

Burnout among European IBD specialists: a survey supported by ECCO

Background: Burnout remains a significant health concern within the healthcare sector. Numerous studies have explored burnout among gastroenterologists. However, as far as we are aware, there is currently no documented research specifically focused on burnout for specialists in the field of inflammatory bowel disease (IBD). Objective: The aim of our study was to assess the extent of burnout, its determinants, and to analyze potential risk factors among European healthcare professionals who provide care to patients with IBD. Methods: We carried out a cross-sectional pilot study involving healthcare professionals responsible for the treatment of patients with IBD. A total of 102 participants (56.9% male, average age 48 ± 10.6) completed the anonymous multiple question open web survey. The survey consisted of four distinct psychological constructs (burnout, depression, somatization, and well-being), along with inquiries associated with sociodemographic, health-related, and work-related factors. Results: In our study, we observed that 47.1% of professionals specializing in IBD experienced burnout. When considering all three factors of burnout simultaneously, 5.9% of participants fell within the moderate range. Among these, depersonalization (DP) was the most prevalent factor, with 48% at a medium level and 47.1% at a high level. Depression, somatization, and well-being correlated with emotional exhaustion (EE) and DP, while only depression correlated with personal accomplishment (PA). Furthermore, age, physical activity, total time spent in healthcare, and time spent as an IBD specialist were correlated with EE. Multiple linear regression analysis revealed that depression was the most dominant predictor of both PA and DP. In terms of work-related factors, we observed that having endoscopic access had a detrimental impact on burnout, while the presence of a dedicated IBD outpatient unit and opportunities to participate in multidisciplinary meetings had a positive effect on mitigating burnout. Conclusions: Our pilot study underscores the importance of burnout among IBD professionals in Europe, with a specific emphasis on DP. Subsequent studies may help to uncover the way underlying factors contribute to burnout, potentially laying the foundation for international support and prevention initiative programs.

A Survey on SQL Injection Attacks Types &amp; their Prevention Techniques

In the world of connectedness even more than ever before we are using digital technologies in daily life from bank transactions to social networking. While all of this data is residing in databases and with increasing usage, the importance of confidentiality and integrity of the data seems to be a challenging and most pressing issue of today’s world. SQL injection are commonly used attacks to gain access to unauthorized data and one such example out of many where an attacker breach the corporate system and stole 130 million credit card details and even after two decades, SQL injection is still one of top ten security threats by open web application security project (OWASP) moving forward with more digitalization in the future it will always be a serious concern since it impacts the core principle of information security such as confidentiality, integrity and availability. In this research project I will be discussing the types of SQL injection mainly in-band, inferential and out of band attacks and keeping scope over in-band SQL injection to further discuss prevention techniques using traditional methods and lastly discussing some of the prevention techniques using advanced algorithms of machine learning and deep learning in the literature.

A comparative study of web application security scanners for vulnerability detection

A Web Vulnerability Scanner (WVS) is a software tool that assesses the security of web applications by conducting automated penetration tests. It speeds up the process, reduces costs, and eliminates the need for specialized testing engineers. This study evaluates the vulnerability detection capabilities of six WVSs, three commercial scanners, and three open-source scanners. The goal is to identify and mitigate potential security risks before they are exploited by malicious users. The study employed two well-known vulnerable web applications and four relevant metrics, such as detection rate of accuracy, recall, precision, and the ability to detect different vulnerabilities using the Open Web Application Security Project (OWASP) as a reference.