scholarly journals Applicability of the Goda–Takahashi Wave Load Formula for Vertical Slender Hydraulic Structures

2020 ◽  
Vol 8 (11) ◽  
pp. 868
Author(s):  
Nadieh Elisabeth Meinen ◽  
Raphaël Daniël Johannes Maria Steenbergen ◽  
Bas Hofland ◽  
Sebastiaan Nicolaas Jonkman

Vertical slender hydraulic structures such as sluices, navigation locks, or storm-surge barriers are often dynamically loaded by waves. For a safe and economic design, an accurate description of the wave loads is needed. A widely used formula for this purpose is the Goda–Takahashi wave load formula (GT). It was derived for the assessment of gravity-based caisson breakwaters. Due to its many advantages, the formula is also often employed for the assessment of vertical slender hydraulic structures, although its applicability to those type of structures was never fully demonstrated. This study provides insights in the applicability of GT for vertical slender hydraulic structures. This is done based on a literature review on the historical backgrounds of GT, and an investigation of several case-studies. In the case-studies, the equivalent-static wave loads for caisson breakwaters in scope of GT are compared with those for vertical slender hydraulic structures. The results show that GT can safely be applied for vertical slender hydraulic structures loaded by pulsating wave loads, but that systematic over- or under-estimations are expected for breaking or impact wave loads. For individual cases, differences up to 200% were obtained. These large over- or under-estimations underline the need for an improvement of the current design tools for vertical slender hydraulic structures loaded by breaking or impact wave loads.

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4109
Author(s):  
Bożena Gajdzik ◽  
Radosław Wolniak

The publication presents a picture of modern steelworks that is evolving from steelworks 3.0 to steelworks 4.0. The paper was created on the basis of secondary sources of information (desk research). The entire publication concerns the emerging opportunities for the development of the steel producers to Industry 4.0 and the changes already implemented in the steel plants. The collected information shows the support environment for changes in the steel sector (EU programs), the levels of evolution of steel mills, along with the areas of change in the steel industry and implemented investment projects. The work consists of a theoretical part based on a literature review and a practical part based on case studies. The work ends with a discussion in which the staged and segmented nature of the changes introduced in the analyzed sector is emphasized. Based on the three case studies described in the paper, a comparative analysis was conducted between them. When we tried to compare methods used in the three analyzed steel producers (capital groups): ArcelorMittal, Thyssenkrupp, and Tata Steel Group, it can be seen that in all organizations, the main problem connected with steelworks 4.0 transition is the digitalization of all processes within an organization and in the entire supply chain. This is realized using various tools and methods but they are concentrated on using technologies and methods such as artificial intelligence, drones, virtual reality, full automatization, and industrial robots. The effects are connected to better relations with customers, which leads to an increase in customer satisfaction and the organizations’ profit. The steel industry will undergo further strong changes, bringing it closer to Industry 4.0 because it occupies an important place in the economies of many countries due to the strong dependence of steel producers on the markets of the recipients (steel consumers). Steel is the basic material needed to make many products, and its properties have been valued for centuries. In addition, steel mills with positive economic, social, and environmental aspects are part of the concept of sustainability for industries and economies.


2021 ◽  
Vol 65 (4) ◽  
pp. 643-651
Author(s):  
Th. Nitschke-Pagel ◽  
J. Hensel

AbstractThe consideration of residual stresses in fatigue-loaded welds is currently done only qualitatively without reliable knowledge about their real distribution, amount and prefix. Therefore, the tools which enable a more or less unsafe consideration in design concepts are mainly based on unsafe experiences and doubtful assumptions. Since the use of explicitly determined residual stresses outside the welding community is state of the art, the target of the presented paper is to show a practicable way for an enhanced consideration of residual stresses in the current design tools. This is not only limited on residual stresses induced by welding, but also on post-weld treatment processes like HFMI or shot peening. Results of extended experiments with longitudinal fillet welds and butt welds of low and high strength steels evidently show that an improved use of residual stresses in fatigue strength approximation enables a better evaluation of peening processes as well as of material adjusted welding procedures or post-weld stress relief treatments. The concept shows that it is generally possible to overcome the existing extremely conservative but although unsafe rules and regulations and may also enable the improved use of high strength steels.


2019 ◽  
Vol 868 ◽  
pp. 244-285 ◽  
Author(s):  
Xiaohui Zeng ◽  
Fajun Yu ◽  
Min Shi ◽  
Qi Wang

For wave loads on cylinders constituting a long but finite array in the presence of incident waves, variations in the magnitude of the load with the non-dimensional wavenumber exhibit interesting features. Towering spikes and nearby secondary peaks (troughs) associated with trapped modes have been studied extensively. Larger non-trapped regions other than these two are termed Region III in this study. Studies of Region III are rare. We find that fluctuations in Region III are regular; the horizontal distance between two adjacent local maximum/minimum points, termed fluctuation spacing, is constant and does not change with non-dimensional wavenumbers. Fluctuation spacing is related only to the total number of cylinders in the array, identification serial number of the cylinder concerned and wave incidence angle. Based on the interaction theory and constructive/destructive interference, we demonstrate that the fluctuation characteristics can be predicted using simple analytical formulae. The formulae for predicting fluctuation spacing and the abscissae of every peak and trough in Region III are proposed. We reveal the intrinsic mechanism of the fluctuation phenomenon. When the diffraction waves emitted from the cylinders at the ends of the array and the cylinder concerned interfere constructively/destructively, peaks/troughs are formed. The fluctuation phenomenon in Region III is related to solutions of inhomogeneous equations. By contrast, spikes and secondary peaks are associated with solutions of the eigenvalue problem. This study of Region III complements existing understanding of the characteristics of the magnitude of wave load. The engineering significances of the results are discussed as well.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ayman Ahmed Ezzat Othman ◽  
Fatma Othman Alamoudy

Purpose This paper aims to develop a framework for optimising building performance through the integration between risk management (RM) and building information modelling (BIM) during the design process. Design/methodology/approach To achieve this aim, a research strategy consisting of literature review, case studies and survey questionnaire is designed to accomplish four objectives. First, to examine the concepts of design process, building performance, RM and BIM; second, to present three case studies to explain the role of using RM and BIM capabilities towards optimising building performance; third, to investigate the perception and application of architectural design firms in Egypt towards the role of RM and BIM for enhancing building performance during the design process; and finally, to develop a framework integrating RM and BIM during the design process as an approach for optimising building performance. Findings Through literature review, the research identified 18 risks that hamper optimising building performance during the design process. In addition, 11 building performance values and 20 BIM technologies were defined. Results of data analysis showed that “Design budget overrun”, “Lack of considering life cycle cost” and “Inefficient use of the design time” were ranked the highest risks that affect the optimisation of building performance. Respondents ranked “Risk avoid” or “Risk transfer” as the most risk responses adopted in the Egyptian context. In addition, “BIM As Built” was ranked the highest BIM technology used for overcoming risks during the design process. These findings necessitated taking action towards developing a framework to optimising building performance. Originality/value The research identified the risks that affect optimising building performance during the design process. It focuses on improving the design process through using the capabilities of BIM technologies towards overcoming these risks during the design process. The proposed framework which integrates RM and BIM represents a synthesis that is novel and creative in thought and adds value to the knowledge in a manner that has not previously occurred.


Author(s):  
David Kristiansen ◽  
Odd M. Faltinsen

This paper addresses wave loads on horizontal cylinders in the free surface zone by means of model tests and numerical simulations. This has relevance for the design of floating fish farms at exposed locations. Two model geometries were tested, where two-dimensional flow conditions were sought. The cylinders were fixed and exposed to regular wave trains. Wave overtopping the models were observed. A two-dimensional Numerical Wave Tank (NWT) for wave load computations is described. The NWT is based on the finite difference method and solves the incompressible Navier-Stokes equations on a non-uniform Cartesian staggered grid. The advection term is treated separately by the CIP (Constrained Interpolation Profile) method. A fractional and validation of the NWT is emphasized. Numerical results from simulations with the same physical parameters as in the model tests are performed for comparison. Deviations are discussed.


2020 ◽  
Author(s):  
Shuchih Ernest Chang ◽  
YiChian Chen

BACKGROUND Blockchain technology is leveraging its innovative potential in various sectors and its transformation of business-related processes has drawn much attention. Topics of research interest have focused on medical and health care applications, while research implications have generally concluded in system design, literature reviews, and case studies. However, a general overview and knowledge about the impact on the health care ecosystem is limited. OBJECTIVE This paper explores a potential paradigm shift and ecosystem evolution in health care utilizing blockchain technology. METHODS A literature review with a case study on a pioneering initiative was conducted. With a systematic life cycle analysis, this study sheds light on the evolutionary development of blockchain in health care scenarios and its interactive relationship among stakeholders. RESULTS Four stages—birth, expansion, leadership, and self-renewal or death—in the life cycle of the business ecosystem were explored to elucidate the evolving trajectories of blockchain-based health care implementation. Focused impacts on the traditional health care industry are highlighted within each stage to further support the potential health care paradigm shift in the future. CONCLUSIONS This paper enriches the existing body of literature in this field by illustrating the potential of blockchain in fulfilling stakeholders’ needs and elucidating the phenomenon of coevolution within the health care ecosystem. Blockchain not only catalyzes the interactions among players but also facilitates the formation of the ecosystem life cycle. The collaborative network linked by blockchain may play a critical role on value creation, transfer, and sharing among the health care community. Future efforts may focus on empirical or case studies to validate the proposed evolution of the health care ecosystem.


Author(s):  
Katleen Vos

In the last decades, worldwide wine tourism has been steadily progressing and has grown substantially as a research object. Several academic papers treat strategies for development and management of wine tourism. This paper aims to describe recent trends in wine tourism, and more specifi­cally, the development of wine tourism in atypical wine regions. Therefore, it synthesises the key findings from the second UNWTO wine tourism conference. Furthermore, it argues that the successful development of wine tourism is not an exact science. Emerging wine destinations often have many dif­ficulties to overcome. Using literature review and case studies, it explores the possibilities to create successful destinations and highlights the impor­tance of co-operation, co-creation within networks and creativity to create value for wine tourism destinations.


2021 ◽  
Author(s):  
Ashley Regimbal-Kung

This paper explored strategies of digital self-promotion for authors online through the investigation of emerging, independent self-published writers. This research provides best practices through those strategies to assist self-published writers in furthering their public profile in digital marketing. The literature review provides context in the online self-publishing environment, connecting with the audience; encouraging collaboration (produsage); adapting to the shifting publishing marketplace through self-presentation strategies (branding), and; bolstering two-way communication (market sensing). It also provides the basis for coding self-presentation themes in self-presentation. This research suggests that best practices can optimize the time that writers spend on marketing, not only to attract initial attention from publishers but at any stage in their career. This research gathers data and develops case studies of four self-published authors that use Wattpad, a social media platform for writers. It analyzes these authors’ strategies for self-promotion and measures their effectiveness through the level of engagement elicited from their fans. It develops best practices from these strategies. This research finds that digital self-promotional activities are successful if they are creative, unique and develop a community of fan followers. It is especially effective when authors reflect the interests of their target audience. It was also found these strategies helped develop the author’s branding for long-term effectiveness


2017 ◽  
Vol 20 (4) ◽  
pp. 209-228 ◽  
Author(s):  
LARISSA MARCHIORI PACHECO ◽  
MARINA KOLLAND DANTAS ◽  
CLÁUDIA SOUZA PASSADOR ◽  
LARA BARTOCCI LIBONI-AMUI

Abstract Several studies analysed the environmental public expenditures, its allocation and role as an instrument for public action. However, there is still a gap in the literature, since there are no works that integrate and systematize the existing knowledge. Therefore, we conducted an integrative literature review, and selected thirty articles for synthesis, classification and coding based on a system proposed by the authors. We identified that researches on this field are still recent and publications are concentrated in Europe and Latin America. Regarding the research methods, the qualitative approach based on case studies was used to develop the majority of the studies. Also, the studies in general combined different spheres of analysis, discussing topics on performance and description of expenses. The results showed that there is a need for studies that promote themes such as transparency, accounting organization and the creation of indicators, enabling deeper analysis. An agenda with eight research suggestions was proposed based on observed theoretical limitations.


2021 ◽  
Vol 16 (1) ◽  
pp. 78-90
Author(s):  
Felicity Tayler ◽  
Maziar Jafary

Objective – In consideration of emerging national Research Data Management (RDM) policy and infrastructure, this literature review seeks answers to the following questions: 1) What is the most effective way for a Canadian research university to build capacity among library and campus-wide research support staff, with a view towards providing coordinated RDM support services for our researcher community?2) What international training models and course offerings are available and appropriate for a local context?3) What national guidelines and best practices for pedagogical design and delivery can be adapted for a local context? Methods – This literature review synthesizes a total of 13 sources: 9 articles, 2 book chapters, and 2 whitepapers. The whitepapers were selected for a narrative literature review because of their focus on case studies detailing train-the-trainer models. Within the 13 sources we found 14 key case studies. This review serves as a supplement to the 2017 CARL Portage Training Expert Group white paper, “Research Data Management Training Landscape in Canada,” the focus of which was to identify RDM training gaps in order to recommend a coordinated approach to RDM training in a national environment. Results – The narrative review of case studies revealed three thematic areas. Firstly, pedagogical challenges were identified, including the need to target training to RDM support staff such as librarians and researchers, as they comprise distinct groups of trainees with divergent disciplinary vocabularies and incentives for training. Secondly, the case studies cover a broad range of pedagogical models including single or multiple sessions, self-directed or instructor-led, in-person or online instruction, and a hybrid of the two. Finally, RDM training also emerged as a key factor in community building within library staff units, among service units on campus, and with campus research communities. Conclusion – RDM training programs at local institutions should be guided by a set of principles aligned with the training methods, modes of assessment, and infrastructure development timeline outlined in a national training strategy. When adapting principles and training strategies to a local context, the following trends in the literature should be considered: librarians and researchers must have meaningful incentives to undertake training in RDM or to join a community of practice; disciplinary-specific instruction is preferable to general instruction; a librarian’s own training opportunities will influence their ability to provide discipline-specific RDM instruction to researchers; in-person training opportunities improve learning retention and produce beneficial secondary effects, whereas online instruction is most effective when paired with an in-person component; generalized third-party RDM training should be adapted to local context to be meaningful. Future directions for RDM training will integrate into open access and digital scholarship training, and into cross-disciplinary, open science communities of practice.


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