Auswahl der wissenschaftlichen Literatur zum Thema „Create React App“

Cellulose cross linking is a very important textile process and has application in the crease resistant finished textile products. N-methylol cross linkers give fabrics desirable mechanical stability properties, but also reduces strength and release formaldehyde, a known human carcinogenic. Our work is based on reactions of particularly hospital green vat dyed cellulose with materials that creates an ionic character to the cellulose. These reactions produce ionic cellulose that can react with a poly ionic material of opposite charge to form cross links. The ionic content of the fabric and various features of the application procedure were varied to optimize the results.

Purpose The purpose of this paper is to compare the value creation of cross-border mergers and acquisitions (M&As) in mature and emerging markets. Design/methodology/approach The empirical study is based on a sample of 285 cross-border M&As announced between 2010 and 2012 and completed by companies of the French SBF 120 index in 54 countries. Findings The statistical analysis shows how financial markets react before and after the announcement of M&As. The obtained findings highlight significant differences: the reaction of financial markets before the announcement is moderately positive for M&As in mature economies, but negative for those in emerging economies; their reaction after the announcement is clearly positive for M&As in mature markets and moderately positive for those in emerging markets. Research limitations/implications Future studies on M&A value creation should differentiate mature and emerging economies and adopt a more in-depth classification of target countries. Practical implications This research emphasizes the necessity to consider country-specific factors for M&A value creation. Originality/value The empirical study is based on a sample of French acquirers, who account for 3 percent of the volume and value of M&As in the world and whose operations are rarely studied in the literature. The authors compare the reaction of financial markets before and after the announcement of M&As conducted in mature and emerging economies.

One of the most interesting problems in Cataclysmic Variables is the long time scale evolution. This problem appears in long time evolution, which is also very important in the search for the progenitor of SN Ia. The classical approach to overcome this problem in the simulation of novae evolution is to assume: (1) A constant in time, rate of mass transfer. (2) The mass transfer rate that does not vary throughout the life time of the nova, even when many eruptions are considered. Here we show that these assumptions are valid only for a single thermonuclear flash and such a calculation cannot be the basis for extrapolation of the behavior over many flashes. In particular, such calculation cannot be used to predict under what conditions an accreting WD may reach the Chandrasekhar mass and collapse. We report on a new code to attack this problem. The basic idea is to create two parallel processes, one calculating the mass losing star and the other the accreting white dwarf. The two processes communicate continuously with each other and follow the time depended mass loss.

Abstract Data Science looks at raw numbers and informational objects created by different disciplines. The Digital Society creates information and numbers from many scientific disciplines. The amassment of data though makes is hard to find structures and requires a skill full analysis of this massive raw material. The thoughts presented here on DS2 - Data Science & Digital Society analyze these challenges and offers ways to handle the questions arising in this evolving context. We propose three levels of analysis and lay out how one can react to the challenges that come about. Concrete examples concern Credit default swaps, Dynamic Topic modeling, Crypto currencies and above all the quantitative analysis of real data in a DS2 context.

In our approach we have combined knowledge of Old Masters (working in this field before the year 1905), New Masters (working in this field after the year 1905) and Dissidents under the guidance of Louis de Broglie and David Bohm. In our model the quantum particle is represented as the Huygens-de Broglie’s particle on the helical path (full wave) guided by the Newton-Bohm entangled helical evolute (Bohmian Pilot Wave). These individual Huygens - de Broglie particles in the Young - Feynman double - slit experiment react with Wilhelm Wien’s photons that are always present inside of the apparatus (Wien’s displacement law). Wilhelm Wien’s photons form collectively the Wien filter guiding the Huygens - de Broglie particles through the double - slit barrier towards a detector (BohEmian Pilot Wave). The interplay of those events creates the observed interference pattern. In the very well-known formula describing the intensity of double-slit diffraction patterns we have newly introduced the concept curvature κ of the Huygens - de Broglie particle and thus giving a physical interpretation for the Newton - Bohm guiding wave (the Bohmian Pilot Wave): for photons κ = π/λ, for electrons κ = 2π/λ. Moreover, we have introduced into that formula the expression λmax from the Wien’s displacement law to describe geometry of the double - slit barrier. We propose to modify the value λmax by the change of the system temperature. There is a second experimental possibility - we can insert into those slits filters to remove Wien’s photons while the Huygens - de Broglie particles continue towards a detector - we should observe the particle behavior. The similar situation might occur in the Mach - Zehnder interferometer. In this case the individual Huygens - de Broglie particle reacts in the first beam splitter with the Wien photon: the Huygens - de Broglie particle goes through one path while the Wien photon goes through the second path. In the second beam splitter they interact again and create the interference pattern on one detector. We can experimentally modify the resulting interference pattern in the Mach - Zehnder interferometer - by the temperature change of the system or by inserting filters to remove Wien’s photons from one or both paths. Can it be that Nature cleverly creates those interference patterns while the Bohmian pilot wave and the BohEmian pilot wave are hidden in plain sight? We want to pass this concept into the hands of Readers of this Journal better educated in the Mathematics and Physics.

Abstract The National Recreation and Park Association (NRPA) is one of four national organizations to receive funding from CDC to disseminate arthritis-appropriate evidence-based interventions (AAEBIs). NRPA has partnered with Fit & Strong!, a CDC-approved AAEBI and National Council on Aging falls prevention program, to disseminate through local park and recreation agencies across the country. To meet the needs of this dissemination effort, Fit & Strong! adapted its in-person instructor training into an online curriculum which became available March 2018. After initial pilot-testing, Fit & Strong! created a five-module training curriculum using Moodle teaching software. The training curriculum uses slides, graphics, videos, and interactive questions to assess mastery. After completing the training, fidelity checks are performed on all instructors by having them video record a class session and share it with the Fit & Strong! team for review. After evaluating the videos, the team meets with the instructors by phone to debrief and advise on any needed improvements. Through this partnership, Fit & Strong! trained an initial cohort of 39 instructors across 18 states within a month’s time. Training evaluation results have been positive. To date, over 900 participants have been reached. A second cohort of approximately 40 new instructors will be trained in Spring 2019. This presentation will review the processes of creating and executing the online training, potential cost and time-saving benefits to CBOs, instructor feedback, and the ease with which instructors can complete the training and offer the program anywhere across the country.

ABSTRACTAlthough many university educators and administrators seek to promote student research, opportunities to do so often are rare or costly. This case study of the undergraduate academic journalClocks&Cloudsprovides a clear model for reaping the rewards of this high-impact educational experience based on peer learning.The goal of this article is to institutionalize knowledge by reviewingClocks&Clouds, American University's undergraduate research journal in political science, international relations, and public policy. Input from three successive teams of student leaders, as well as interviews with administrators and faculty members at American University, suggests a method for creating a journal and "lessons learned" that can be applied at other institutions. The article builds on the research of Mariani et al. (2013), which considered various organizational strategies that political science departments use to structure undergraduate student publications. It highlights three facets of a model undergraduate journal in political science: organizational structures, peer-review process, and funding and resources. The purpose of this study was to encourage other undergraduate programs in political science to create student research publications and expand the reach of this high-impact educational practice.

Theory suggests that the vision-for-perception and vision-for-action processing streams operate under very different temporal constraints ( Glover, 2004 ; Goodale, Jackobson, & Keillor, 1994 ; Graham, Bradshaw, & Davis, 1998 ; Hu, Eagleson, & Goodale, 1999 ). With the present study, children and young adults were asked to estimate how far a cued target was from a response target in immediate and response-delay conditions. Based on maximum reach of each participant, target locations in peripersonal and extrapersonal space were created. ANOVA results for accuracy indicated differences between Age within Condition and Space. Overall, adults were more accurate than children. Analysis revealed that with delays of superior or equal to 2 s, performance affected all groups, but most notably the 5- and 7-year-olds. In summary, these findings suggest that young children have greater difficulty processing allocentric cues in the context of reach in delay paradigms.

Based on interviews with Swiss journalists who specialise in war and international reportage, this article investigates the extent to which social media impacts on reportage of war and conflict. The interviews examine journalists’ perceptions of the threats and opportunities posed by use of social media in reporting conflict, by investigating how journalists position themselves and their practices within this new media ecosystem. In particular, the interviews explore whether challenges to professional journalism encountered in previous studies of reportage of war and conflict are overcome by the use of social media. It explores if social media can mitigate the effects of military and government restriction of information, changing newsroom dynamics and issues of audience engagement in reportage of conflict. The findings highlight that in the context of war and conflict the dynamism creates opportunities for fast, news dissemination, pluralised voices in reportage and extended audience reach. However, reporters must also negotiate the complexities that fast, multi-medium and multi-sourced information create for reporting practices, especially in terms of verification of information and contextualisation. Thus this article argues that although social media adds dynamism to journalistic environments, this dynamism also brings new levels of complexity to journalistic practice that professional media workers must negotiate.

Information and communication technology (ICT) is evolving at an accelerating pace. Competition law and policy aim to secure an active competition process in the market in order to protect customers in their own countries, regardless of the nationality of the actors, including the ICT industry. As the platforms become more oligopolistic, the Japanese government has established a data portability that enables users to transfer from any specific platform, at any time, to open up an environment where new platform-type businesses are created one after another and where active competition is carried out. In this policy discussion, it is necessary to seek methods that include realistic international cooperation that is not subject to regulation or intervention-oriented measures. In addition, discussion based on economic empirical analysis is particularly needed. From the viewpoints of ensuring innovative research and development (R&D) concerning artificial intelligence (AI) and fair competition generally, the way of the Governance of AI Networking should be a nonregulatory and a nonbinding way, taking technical features and responsibility distribution among stakeholders (developers, providers, end users, and third parties) into account.

Webbapplikationer bygger på många olika webbramar och utvecklare har en mängd olika webbramverk att välja mellan när de utvecklar en webbapplikation. Två populära webbramverk som finns på marknaden är NextJS och Create React App (CRA). Varje ramverk har sina egna för- och nackdelar i olika perspektiv. Syftet med denna studie är att granska om det finns några skillnader i dessa två populära webbramverk ur ett kontinuerligt integrations och kontinuerligt leverans-perspektiv med ett fokus på att kolla närmare på skillnaderna inom utvecklingsprocessen vid utökningar av applikationer och den tid det tar att bygga och driftsätta applikationer i de olika ramverken. För att få kunskap om ämnet så har en teoretisk studie av webbaserade källor gjorts och en applikation har skapats i de båda ramarverken för att sedan utvidgas med ytterligare verktyg för att kunna utföra en jämförelse. Studien visar att ramverken resulterar i liknande byggoch driftsättningstider men skiljer sig dock åt gällande konfigurationer när applikationerna utökades och att NextJS gav en enklare åtkomst åt konfigurering.
Web applications are built on numerous of different web frameworks and developers have a plethora of different web frameworks to choose from when developing a web application. Two popular web frameworks on the market are NextJS and Create React App (CRA). Each framework has its own advantages and disadvantages in different perspectives. The objective of this study is to review if there are any differences in these two popular web frameworks in a continuous integration and continuous delivery perspective looking closer at the differences in the development process when extending applications and the time it takes to build and deploy applications in the different frameworks. To gain knowledge about the subject, a theoretical study on web based sources has been made and an application has been created in both framework to then be extended with further tools to be able to perform the comparison. The study shows that the frameworks results in similar build and deployment times but does however differ in the configurations when extending applications and that NextJS did provide a more straightforward configuration.

In this sixth volume, a committed set of authors explore the Psychology field, therefore contributing to reach the frontiers of knowledge. Success depends on the participation of those who wish to find creative solutions and believe in their potential to change the world, altogether, to increase public engagement and cooperation from communities. Part of our mission is to serve society with these initiatives and promote knowledge. Therefore, it is necessary the strengthening of research efforts in all fields and cooperation between the most assorted studies and backgrounds. In particular, this book explores five major areas (divided into five sections) within the broad context of Psychology: Social Psychology, Cognitive and Experimental Psychology, Clinical Psychology, Legal Psychology and Educational Psychology. Each section comprises chapters that have emerged from extended and peer reviewed selected papers originally published in the proceedings of the International Psychological Applications Conference and Trends (InPACT 2020) conference series (http://www.inpact-psychologyconference.org/). This conference occurs annually with successful outcomes. Original papers have been selected and its authors were invited to extend them significantly to once again undergo an evaluation process, afterwards the authors of the accepted chapters were requested to make corrections and improve the final submitted chapters. This process has resulted in the final publication of 33 high quality chapters.

Two librarians at a University in New Hampshire attempted to integrate gamification and mobile technologies into the exploration of, and orientation to, the library's services and resources. From augmented reality to virtual escape rooms and finally an in-house app created by undergraduate, campus-based, game design students, the library team learned much about the triumphs and challenges that come with attempting to utilize new technologies to reach users in the 21st century. This chapter is a narrative describing years of various attempts, innovation, and iteration, which have led to the library team being on the verge of introducing an app that could revolutionize campus discovery and engagement.

This chapter aims to present the process of selecting and analyzing a number of reviews using a software solution (an online application) created specifically for text analysis and extracting user sentiment. This software measures the level of user satisfaction, analyzing product reviews and taking into account the qualitative part of the content generated by users. Analyzing online customer reviews with the help of specialized software can help both companies and other users. The software can also help us reach a conclusion regarding the analysis of reviews and customer feedback on products or services. This study can also be useful for customers or buyers who want to know the opinion of others about a product, having the opportunity to differentiate between positive and negative reviews.

Technological progress and the evolution of the directives concerning the construction sector have led to a significant digitalization of information concerning buildings. One of the challenges that have arisen concerns the use of data in the phases of the life cycle following the construction. How can this information be exploited? Is it possible to use it directly in a facility management tool that is within the reach of expert users and not? The aim of this chapter is reporting the developed framework to support the management and maintenance operations in buildings, defined within the project AR4FM - Augmented Reality for Facility Management. In particular, AR4FM aims to create an innovative software ecosystem that uses the most modern technologies to support facility management (FM) operations through a set of bespoke applications. The first tool is the web-based ICT platform usable through web-browser, while the second tool refers to a mobile App, called AR4FM mobile app, which will enable visualization for both mobile and wearable devices, such as smart-glasses.

One of the driving factors in IT development is the availability of cheap and efficient network technologies. The Internet is no longer used only as a medium for personal communication. Organizations start utilizing this technology to link existing applications and to create new ones. While traditionally systems were designed to respond to interactive user requests, they are now more and more aiming at autonomous, distributed data processing. Systems are connected and instantly react to changes to improve their functionality and utility (cf. zero latency enterprises). Mobile systems and other volatile configurations demand reactions to continuous changes; finance applications must be notified of price fluctuations; supply chain management must observe stock level changes; and information retrieval applications must forward new content (Banavar, Chandra, Strom, & Sturman, 1999; Gray, 2004).

Firms and organizations are increasingly exploiting electronic channels to reach their customers and create new business opportunities. To this end, electronic shops have been developed, either offering products from a single firm or encompassing multiple individual electronic stores, comprising thus electronic shopping malls. Besides development activities, electronic shopping has attracted the attention of researchers, who have studied various perspectives, including user attitude, critical success factors, security, technical aspects, and so forth (e.g., Fang & Salvendy, 2003; Wang, Makaroff, & Edwards, 2003). Two main concerns for e-commerce are personalization and enhancement of user experience. Personalization addresses the ability to offer content tailored to the preferences of each user (Anupam, Hull, & Kumar, 2001) or user group (Wang et al., 2003). Preferences may be explicitly declared by the user, or derived by the system through inspecting user interaction; if the system dynamically reacts to changes of visitor behavior, it is termed as adaptive. Personalization allows customers to focus on the items they are interested in, and enables electronic shops to make targeted suggestions and send promotions to customers (Lekakos & Giaglis, 2005). Enhancement of user experience is another major issue in e-commerce, given that 2D images and texts on the screen are not sufficient to provide information on product aspects such as physical dimensions, textures, and manipulation feedback (Park & Woohun, 2004). Major e-commerce categories that could benefit from giving a more accurate and/or complete view of the products include real estate brokers who could present detailed models of properties, furniture stores that could allow their customers to view how certain pieces would fit in the target place (Hughes, Brusilovsky, & Lewis, 2002), and clothing shops that could provide a virtual fitting room with customizable avatars (Compucloz Corporation, 2003). Multimedia presentations can also be used as a means for “information acceleration” for promoting “really new” products (Urban et al., 1997). Enhancement of user experience may finally compensate for the loss of the pleasure associated with a visit to a shopping mall (Laskaridis, Vassilakis, Lepouras, & Rouvas, 2001). Nowadays, the technological potential of Internet systems provides adequate means for building online multimedia applications that can help e-commerce sites attract e-shoppers. Applications can be built to adapt to the user’s profile and provide the user with a suitable set of information in the most efficient way. Virtual reality (VR) technologies are also now mature enough to be used for the wide public, offering vivid and highly interactive environments, allowing users to view synthetic worlds within which they can visualize and manipulate artifacts. This article aims to specify a system that exploits capabilities offered by adaptation and VR technologies to offer e-shoppers personalized and enhanced experiences, while addressing challenges related to the cost, complexity, and effort of building and maintaining such a system.

Population growth, industrialisation, urbanisation, and climate change have created huge pressure on freshwater resources to fulfil the demand. Approx. 70-80% of the freshwater supply returns as wastewater, which is difficult to tackle and manage. We need to tackle the freshwater demand from different sectors like domestic, industrial, and agriculture. Most important is how to use the wastewater safely in agriculture. Therefore, it is an apt time to refocus on ways to recycle water especially in sectors like agriculture and for ecosystem services. The major concern in using wastewater in agriculture is its quality as the wastewater may carry pathogens, heavy metals, and many other pollutants, which might reach to human beings and animals via food chain. A solution to wastewater reuse is through bioremediation techniques. Bioremediation should be considered as a feasible and futuristic technology for safe use of wastewater in agriculture as it will reduce the burden on centralised water treatment system as well as it being economic and eco-friendly.

Conversation practice is essential for second-language acquisition and necessary for learners to reach an acceptable communicative level. In an ideal scenario, students should regularly hold conversations with native speakers of the target language, but this is often not possible. Although the teachers use the target language during the classes, they cannot offer a continuous conversation with each student, and they are usually not available wherever and whenever the student requires them to practice. This chapter presents the development and use of a mobile application to hold conversations in the Japanese language. The objective is to provide a software tool to improve the level of communicative competence (both inside and outside a classroom environment). So, the authors created and used a conversational agent (chatbot) using Dialogflow (a Google API), which is connected to the application's interface through the Internet using a client access token to give responses to user inputs in real time.

The rapid growth of Internet technologies induced a structural change in both social and economic spheres. Digital channels have become an integral part of daily life, and their influence on the transfer of information has become ubiquitous. An entirely new business dimension that may be referred to as the Net economy has emerged. Internet-based e-ventures that are operating at this electronic trade level are based on innovative and promising online business models (Kollmann, 2006). But also traditional enterprises that are operating at the physical trade level (real economy) increasingly utilize digital channels to improve their business processes and to reach new customer segments. With the Internet, the cooperation between enterprises reached a new level of quality. The wide, open, and cost-effective infrastructure allows a simple, fast exchange of data and thus a synchronization of business processes over large distances. Particularly for e-ventures introducing their new business ideas, online cooperation is a promising strategy as it enables the partners to create more attractive product offers and represents a basis for more efficiently and effectively communicating and distributing their product offers (Kollmann, 2004; Volkmann & Tokarski, 2006). Online cooperation, however, does not incorporate off-line channels such as print media, stores, or sales forces. For the combined management of online and offline channels, cooperation can be expected to hold an outstanding potential. Partnering with companies from the Net economy may help traditional enterprises to reach new market segments without extending themselves beyond their core competencies—and vice versa. In this context, cross-channel cooperation can be defined as the collaborative integration of online and offline business models aiming at attaining positive synergetic effects for the involved partners by a complement of competencies. (Kollmann & Häsel, 2006, p. 3) Cross-channel cooperation can be regarded a new management task that is worthwhile to be examined in more detail. Although researchers have broadly covered the area of online cooperation, a comprehensive study on cross-channel cooperation has not been undertaken up to now. Particularly the question arises, which cooperation forms represent feasible strategies for both e-ventures and traditional enterprises. Besides its contribution to literature, this article is intended to assist practitioners in evaluating the benefits of crosschannel cooperation for their own businesses.

Public relations is about the “ethical and strategic management of communication and relationships” (Johnston & Zawawi, 2004, p. 6) with individuals and groups (“publics”) important to an organization. At one time such publics could safely be thought of in relatively static terms such as geographic location. This is, of course, still possible—but such fixed categories are of diminishing importance when it comes to building relationships with modern publics and communicating organizational messages to them. Even the motor vehicles that facilitate physical movement are becoming “smarter” and converging with technologies such as mobile telephony, personal entertainment systems and handheld computing (Sherry & Urry, 2000, as cited in Sheller, 2002). This article aims to explore the idea that mobile technologies mean PR practitioners must rethink both the notion of publics and also how to relate to them. A “mobile PR” will undermine takenfor- granted views about the nature of media, messages, and the kinds of relationships public relations people can expect to create on behalf of their clients. Many practitioners are still getting to grips with the online public relations they have known—through activities such as arranging the building of corporate Web sites, monitoring online discussions relevant to client interests and both disseminating company information online and responding to inquiries about it. The idea of an even more flexible communications environment enabled by mobile technologies may seem very daunting. No-one has so far worked out how to “do” PR in this new communications climate— there are no prescriptions or generally accepted approaches. Yet if practitioners do not confront the dilemma of how to reach mobile audiences they risk becoming irrelevant to many clients who must communicate in the mobile space or face unacceptable decay in their business.

Systems engineering (SE) and SE management is the objective of all SE efforts, which defines the transformation of specific customer needs into a system product, service, or enterprise systems. Enterprise systems of systems engineering apply systems engineering fundamentals to the design of an enterprise. It is created by knowledge, principles, and processes tailored to the design of enterprise systems. Enterprise is a complex, socio-technical system that includes interdependent resources of people, information, and technology to reach a common goal. Enterprise systems is complex that a system configuration can be controlled among the different stakeholders. There are four different steps in enterprise systems process; it includes technology planning (TP), capabilities-based engineering analysis (CBEA), enterprise architecture, and enterprise analysis and assessment. This is the main reason that the enterprise work is developed and established at HAVELSAN Inc., Information and Security Technology Division. SE and technical processes for enterprise projects require establishing a systematic taxonomy and SE process customization. This chapter presents the work done on SE for enterprise projects at HAVELSAN. The chapter presents the results of the study of similarities and differences of the various applications of systems engineering of product systems oriented against enterprise systems.

Abstract Scope Controlled dissolution glasses form a permanent consolidating mineral matrix inside formations with either permeable or impermeable properties. The unique solution has a low injection viscosity and can be easily injected into a wide range of formations. The application method is simple and does not require multiple fluids or pre- and post-flushing. This paper focuses on the benefits of controlled dissolution glasses and potential applications in the oil and gas industry. Methods, Procedures, Process Controlled dissolution glasses have been researched extensively by Glass Technology Services (GTS) since 1999 for the biomedical industry, nuclear waste storage industry, and defense and aerospace industries. GTS together with operators have been performing research and development for the oil industry over the last 10 years. The research investigated different glass compositions to determine their injectability and change in formation properties post-treatment. Sandstone, chalk, and shale formations were used in the testing. Flow testing using a Hoek cell and a core flood apparatus was used to determine the post-treatment permeability. For post-treatment strength measurement, Brazilian tensile strength tests and modified cone penetration tests were used to determine tensile strength and shear strength respectively. The testing evaluated different mixing fluids, such as water and different brines, compatibility, corrosion testing, and concentrations. Results, Observations, Conclusions The testing identified different glass compositions and concentrations that are suitable for different applications and formations. Certain glass compositions increase tensile strength significantly while also maintaining the permeability in the formation. Other glass compositions have similar tensile strength increase, but result in an impermeable seal. The liquid glass solutions react with the formation to form a mineral precipitation inside the formation. The reaction with the formation occurs quickly at downhole conditions, within hours of placement. The glass can be mixed with water and variety of brines to form a stable solution across a range of densities. The testing and results to date have laid the foundation for use in a variety of consolidation and P&A applications in oil and gas wells. Testing is ongoing for a chalk and sandstone consolidation solution and for a sealing solution. Novel/Additive Information These novel glass solutions can solve many of the production and instability challenges that plague weak formations. The glasses can be injected into very low permeability formation to either seal or consolidate.

Abstract Because of the effects of gravity acting on the melt region created during the laser sintering process, additively manufactured surfaces that are pointed upward have been shown to exhibit roughness characteristics different from those seen on surfaces that point downward. For this investigation, the Roughness Internal Flow Tunnel (RIFT) and computational fluid dynamics models were used to investigate flow in channels with different roughness on opposing walls of the channel. Three rough surfaces were employed for the investigation. Two of the surfaces were created using scaled, structured-light scans of the upskin and downskin surfaces of an Inconel 718 component which was created at a 45° angle to the printing surface and documented by Snyder et al. [1]. A third rough surface was created for the RIFT investigation using a structured-light scan of a surface similar to the Inconel 718 downskin surface, but a different scaling was used to provide larger roughness elements in the RIFT. The resulting roughness dimensions (Rq/Dh) of the three surfaces used were 0.0064, 0.0156, and 0.0405. The friction coefficients were measured over the range of 10,000 < ReDh < 70,000 for each surface opposed by a smooth wall and opposed by each of the other rough walls. At multiple ReDh values, x-array hot film anemometry was used to characterize the velocity and turbulence profiles for each roughness combination. The friction factor variations for each rough wall opposed by a smooth wall approached complete turbulence. However, when rough surfaces were opposed, the surfaces did not reach complete turbulence over the Reynolds number range investigated. The results of inner variable analysis demonstrate that the roughness function (ΔU+) becomes independent of the roughness condition of the opposing wall providing evidence that Townsend’s Hypothesis holds for the relative roughness values expected for additively manufactured turbine-blade cooling passages.

Abstract A major Exploration and Production (E & P) company was posed with a challenge of sustained casing pressure in over 85% of the wells drilled in one of the fields in the Offshore Niger Delta. Sustained casing pressure occurs when the annular seal is damaged and a path is created for the formation pressure to reach the surface, and the pressure in the annulus rebuilds after being bled down. When cementing in such an environment, operators have the following objectives: Placing a cement sheath with increased capability to survive future downhole stress events.Achieving effective mud removal.Gaining the benefits of a react and respond sheath design.Providing a long productive life for the wellbore. To develop a cement system that would achieve and maintain isolation throughout the life of the well, an advanced cement technology was required. This advanced cement technology involved Finite Element Analysis (FEA) to model the effects of stresses from well operations on the cement sheath. This analysis takes into consideration well configuration, formation properties, casing properties, cement properties and operational loads and predicts the remaining capacities of the cement sheath. The remaining capacity is used to measure how much a cement sheath is stressed. After simulating the effect of downhole stresses on a cement sheath, a mechanically enhanced cement slurry was designed to meet the recommendations of the model and provide a cement sheath with improved remaining capacity. This paper presents the successful mechanically enhanced slurry design, job design, planning and execution on the production section of the well after a Finite Element Analysis was conducted. Post job conditions such as good cement bonds across cemented areas, well production without inter-zonal communication and no annular pressure build up in over 8 years have proven the success of the design and the procedure implemented in these challenging well bore environments. The success of this well has been applied to two additional wells.

Most commercially available lower-limb prostheses are designed for walking, not for standing. The Minneapolis VA Health Care System has developed a bimodal prosthetic ankle-foot system with distinct modes for walking and standing [1]. With this device, a prosthesis user can select standing or walking mode in order to maximize standing stability or walking functionality, depending on the activity and context. Additionally, the prosthesis was designed to allow for an “automatic mode” to switch between standing and walking modes based on readings from an onboard Inertial Measurement Unit (IMU) without requiring user interaction to manually switch modes. A smartphone app was also developed to facilitate changing between walking, standing and automatic modes. The prosthesis described in [1] was used in a pilot study with 18 Veterans with lower-limb amputations to test static, dynamic, and functional postural stability. As part of the study, 17 Veterans were asked for qualitative feedback on the bimodal ankle-foot system (Table 1). The majority of participants (82%) expressed an interest in having an automatic mode. The participants also indicated that the automatic mode would need to reach walking mode on their first step and to lock the ankle quickly once the standing position was achieved. When asked about how they wanted to control the modes of the prosthesis, 82% wanted to use a physical switch and only 12% wanted to use a smartphone app. The results indicated that the following major design changes would be needed: 1) A fast and accurate automatic mode 2) A physical switch for mode changes This paper describes the use of machine learning algorithms to create an improved automatic mode and the use of stakeholder feedback to design a physical switch for the bimodal ankle-foot system.

A new theoretical approach on the determination of the conditions for the initiation of the motion of the ballast stones due to the wind gust created under the high-speed trains has been recently developed (Sanz-Andres & Navarro-Medina, 2009). This determination is critical to predict the starting of ballast pick-up, because once the motion is initiated a saltation-like chain reaction could take place. Sometimes the flying stones reach an height which is larger than the lowest parts of the train, striking them (and the track surroundings) producing considerable damage that are to be avoided e.g. by limiting the maximum allowed operational train speed. The aim of this contribution is to present the experimental results that have been obtained to check the validity of the proposed model. The experimental facility is a wind tunnel, with a gust generator, with a maximum wind speed of some 20 m/s (65.6 ft/s) and 10 Hz gust frequency. The test section is 0.39 m × 0.54 m (15.4 in × 21.3 in), which is suitable to perform experiments with stone models. It is shown that in the range of parameters explored, the experimental results are in good agreement with the theoretical model predictions. In this contribution the theoretical model is summarized, the experimental facility is described, showing some of its typical performances, the experimental procedure is outlined, and the experimental results are compared with the theoretical predictions.

MAN Diesel & Turbo recently developed a completely new gas turbine family for the first time in its history. The first product line contains both two-shaft and single-shaft gas turbines in the 6 – 7 MW class. The two-shaft engine was thoroughly tested at MAN’s gas turbine test center, and the first engine has been delivered to a launch customer. For MAN, it constitutes a technology platform that will produce further developments and new models in the coming years. The two-shaft design makes the new gas turbine an ideal mechanical drive for both turbo compressors and pumps. This gas turbine operates to suit the optimum duty point of the driven machine; both in a wide speed and power range. The two stage power turbine design allows for a wide speed range of 45 to 105% while maintaining high efficiency. For power generation a single-shaft version has been created by adding one additional stage to the two stage high pressure turbine. The compressor pressure ratio is 15, which is high enough for achieving the highest potential efficiency for both generator and compressor drive applications. Low pollutant emission levels are achieved with MAN’s DLN combustion technology. The gas turbine exhaust temperature is sufficiently high to reach high heat recovery rates in combined heat and power cycles. Another important feature of the new gas turbine is its unrestricted suitability for taking load quickly and rapid load changes. Service costs have also been significantly improved upon. MAN opted for a sturdy and modular gas turbine construction, while not compromising on efficiency. The objective is to extend service life and shorten down time occurrences. The modular package assembly process helps to reduce routine maintenance and repair time, and ultimately package downtime.

Abstract The process of designing a 3D wellbore trajectory, in general, takes into consideration only the expected initial and final coordinates, some “drillable” curvatures that can be delivered by the current technologies, and any of the various 3D planning models, each with a particular number of defining parameters. Some of the questions usually disregarded are: which model to take to design the trajectory, which values to take for the defining parameters, what to measure in the process of design, and what should be optimized. The objective of this work is to provide a systematic approach to 3D trajectory design based on torque and drag performance. For this purpose, it is unquestionable that the torque and the drag caused by the trajectory curvature, which are, considering all other variables the same, determined by the trajectory model and its parameters, dominate the discussion. Other things like trajectory length, borehole diameter, tubular good geometry, although influential, are irrelevant in the decision process because if they affect one model, they affect all others. Therefore, the use of an efficient, accurate, and general T&D model is of fundamental importance, and then we are left with the duty of measuring the adequate cost (or loss, or objective) function and optimizing this function. In this endeavor, a fast and accurate 3D stiff analytical T&D solution that allows analyzing a large number and wide range of parameters is of fundamental importance. Armed with such tool, and with the guidelines resulting from this work, the well designer can quickly determine the best trajectory and parameters that optimize the borehole construction and yet reaching the fundamental purpose of the well to be designed. Instead of requiring an extensive experience and/or creative (non-replicating) capacity of the well designer, the process delivers a systematic approach to trajectory design, based on the relevant objective parameters (e. g., minimum T&D, minimum equipment wear, reduced casing, cementing, hole cleaning and pipe sticking difficulties, and so far). To reach this goal a reasonable, but not thorough, understanding of the causes and effects of torque and drag is necessary in order to effectively play with the trajectory parameters. The causes and consequences of wellbore tortuosity is particularly discussed. In the process, several types of trajectory common in the industry are used and compared. To effectively compare the various models, it is assumed that all trajectories (based on the same initial and final conditions) have the same length (measured depth). This is not a necessary condition because different trajectory construction may require different amount of curvature control, which affects its cost. The T&D model itself is not covered because it has been discussed in another publication; however, a brief discussion is presented in the Annex 2. Any appropriate model serves the purpose although the requirement of being fast, accurate, 3D, and using a stiff model is necessary. Flexibility and efficiency on how the data are entered and changed are also important to a successful, efficient analysis.

In 1986, the NRC issued the Information Notice (IN) 86-05 “Main Steam Safety Valve test failures and ring setting adjustments”. Shortly after this IN was issued, the Code was revised to require that a full flow test has to be performed on each CL.2 MSSV by the manufacturer to verify that the valve was adjusted so that it would reach full lift and thus full relieving capacity and would reclose at a pressure as specified in the valve Design Specification. In response to the concern discussed in the IN, the Westinghouse Owners Group (WOG) performed extensive full flow testing on PWR MSSVs and found that each valve required a unique setting of a combination of two rings in order to achieve full lift at accumulation of 3% and reclosing at a blowdown of 5%. The Bopp & Reuther MSSV type SiZ 2507 has a “fixed blowdown” i.e. without any adjusting rings to adjust the “blowdown” so that the blowdown is “fixed”. More than 1000 pieces of this type are successfully in nuclear power plants in operation. Many of them since about 25 years. Therefore it can be considered as a proven design. It is new that an optimization of this MSSV type SiZ 2507 fulfill the requirements of part NC-7512 of the ASME Section III although there are still no adjusting rings in the flow part. In 2000, for the Qinshan Candu unit 1&2 full flow tests were performed with 32 MSSV type SiZ 2507 size 8” × 12” at 51 bar saturated steam in only 6 days. In all tests the functional performance was very stable. It was demonstrated by recording the signals lift and system pressure that all valves had acceptable results to achieve full lift at accumulation of 3% and to reclose at blowdown of 5% . This is an advantage which gives a reduction in cost for flow tests and which gives more reliability after maintenance work during outage compared to the common MSSV design with an individual required setting of the combination of the two rings. The design of the type SiZ 2507 without any adjusting rings in the flow path is presented. The stable performance depends on the interaction of flow force and spring force. The optimization of the flow path to create a suitable flow-force-curve was managed by Computational Fluid Dynamics (CFD) and flow-force-characteristic-measurements at a model 1: 2.5 ! The method of the flow-force-characteristic-measurement permits systematic dimensioning of valve spring forces by means of measurement of the fluid mechanical forces occurring on the valve spindle during flow [1], [2]. A special procedure was established to verify a spring force versus lift curve with an accuracy of 1% for each production valve. This gives high reliability at required stable performance and this can not be influenced by wrong setting of any adjusting ring during maintenance work.

Production of oil and gas in the Brazilian pre-salt will face several technical challenges. One of them that is a major concern is the presence of CO2 in high concentrations. Indeed, since the local regulatory agency requires increasingly stricter recommendations, it seems unlikely the possibility of simply release CO2 in the atmosphere. Besides that, as it happens since the 1970’s in USA, enhanced oil recovery (EOR) using CO2 might be a great opportunity and has to be considered. If that is the case, as soon as CO2 is separated from the oil in the top side, it has to be pressurized and transported through pipelines into the reservoir. The material of choice for that pipeline would be API 5L X65 since it is widely used and most available. The working pressure can reach up to 500 bar or more and it is an important issue to consider the fact that a suddenly depressurization due to a crack in the pipeline or a failure in a fastener or flange can promote a local abrupt decrease in temperature down to −60°C or even lower. That concern in addition to the fact that cathodic protection has to be used in the pipeline for corrosion control has the potential to produce embrittlement due to a combination of low temperature and hydrogen charging and ultimately lead to a catastrophic failure. The use of nickel to improve steel toughness has been used extensively and some grades or classes of nickel containing steels have been created for special applications. The aim of this work is to evaluate whether a nickel containing steel would be a more suitable material to manufacture high pressure CO2 transporting pipelines, taking in account a possible leak and the corresponding effect of a local and abrupt drop in temperature on the fracture toughness of the material. The effect of hydrogen due to cathodic protection on fracture toughness is also evaluated. The results indicated that under the experimental conditions and materials examined here the 9%wt nickel steel is not sensitive to low temperature and hydrogen, practically maintaining its original fracture toughness.

Flying requires a high power density in the propulsion system. Currently only turbofan engines can provide the required power at a low system mass. To counter a potential negative impact of aircraft emissions on global climate, the agreement Flightpath 50, created by European research establishments and industries, has set the target to reduce overall CO2 emissions from the year 2000 to 2050 by 75 %. In contrast, the air traffic volume has been growing constantly since the 1980s and will be growing further. Hence the fuel burn of aero engines has to be reduced to reach the Flightpath 50 target. High-end component technology has nearly exhausted full potential in the improvement of conventional turbofan engines. Further significant progress can only be achieved by new engine concepts. The geared turbofan has proven the feasibility of this approach. The introduction of a gear allows the IPC and LPT to run at more suitable speeds with the consequence of a lower stage count compared to conventional turbofans. According to Pratt&Whitney this will reduce the fuel burn by ”15–16% versus today’s best engines” [1]. As a next step towards Flightpath 50 MTU Aero Engines AG envisioned the Intercooled Recuperative Aero Engine (IRA) for long-haul application. This concept increases the thermodynamic efficiency of the core engine by utilizing two heat exchangers: an intercooler reduces the work which is necessary for the compression. A recuperator transfers heat of the exhaust gas to the compressed gas entering the burner. In long-haul aircraft the increased engine mass due to the heat exchangers has a lower influence on the fuel burn. To broaden the research, this paper investigates the application of the IRA for regional jets. An extensive predesign parameter study was performed to find the optimal IRA configuration for regional jets. Not only has fuel consumption been taken into consideration, additionally the influence of the increased weight of the IRA has been included. In optimum, the fuel burn on a regional mission according to this study could be reduced in the order of 1–2%. However, the overall pressure ratio is much lower compared to modern turbofan engines, which leads to relatively low NOx emissions. It allows the introduction of Lean Premixed Prevaporized (LPP) burner technology, promising an additional significant reduction in NOx emissions compared to modern turbofan engines. Compared to a longhaul application the heat exchangers are not a scaled version but the result of a cycle optimization considering the available space. The paper also gives an outlook for an innovative three dimensional heat exchanger. The novel heat exchanger arrangement promises a better integration into the annulus at turbine exit and less aerodynamical pressure losses due to 3D-effects.

This report maps the African landscape of Open Science – with a focus on Open Data as a sub-set of Open Science. Data to inform the landscape study were collected through a variety of methods, including surveys, desk research, engagement with a community of practice, networking with stakeholders, participation in conferences, case study presentations, and workshops hosted. Although the majority of African countries (35 of 54) demonstrates commitment to science through its investment in research and development (R&D), academies of science, ministries of science and technology, policies, recognition of research, and participation in the Science Granting Councils Initiative (SGCI), the following countries demonstrate the highest commitment and political willingness to invest in science: Botswana, Ethiopia, Kenya, Senegal, South Africa, Tanzania, and Uganda. In addition to existing policies in Science, Technology and Innovation (STI), the following countries have made progress towards Open Data policies: Botswana, Kenya, Madagascar, Mauritius, South Africa and Uganda. Only two African countries (Kenya and South Africa) at this stage contribute 0.8% of its GDP (Gross Domestic Product) to R&D (Research and Development), which is the closest to the AU’s (African Union’s) suggested 1%. Countries such as Lesotho and Madagascar ranked as 0%, while the R&D expenditure for 24 African countries is unknown. In addition to this, science globally has become fully dependent on stable ICT (Information and Communication Technologies) infrastructure, which includes connectivity/bandwidth, high performance computing facilities and data services. This is especially applicable since countries globally are finding themselves in the midst of the 4th Industrial Revolution (4IR), which is not only “about” data, but which “is” data. According to an article1 by Alan Marcus (2015) (Senior Director, Head of Information Technology and Telecommunications Industries, World Economic Forum), “At its core, data represents a post-industrial opportunity. Its uses have unprecedented complexity, velocity and global reach. As digital communications become ubiquitous, data will rule in a world where nearly everyone and everything is connected in real time. That will require a highly reliable, secure and available infrastructure at its core, and innovation at the edge.” Every industry is affected as part of this revolution – also science. An important component of the digital transformation is “trust” – people must be able to trust that governments and all other industries (including the science sector), adequately handle and protect their data. This requires accountability on a global level, and digital industries must embrace the change and go for a higher standard of protection. “This will reassure consumers and citizens, benefitting the whole digital economy”, says Marcus. A stable and secure information and communication technologies (ICT) infrastructure – currently provided by the National Research and Education Networks (NRENs) – is key to advance collaboration in science. The AfricaConnect2 project (AfricaConnect (2012–2014) and AfricaConnect2 (2016–2018)) through establishing connectivity between National Research and Education Networks (NRENs), is planning to roll out AfricaConnect3 by the end of 2019. The concern however is that selected African governments (with the exception of a few countries such as South Africa, Mozambique, Ethiopia and others) have low awareness of the impact the Internet has today on all societal levels, how much ICT (and the 4th Industrial Revolution) have affected research, and the added value an NREN can bring to higher education and research in addressing the respective needs, which is far more complex than simply providing connectivity. Apart from more commitment and investment in R&D, African governments – to become and remain part of the 4th Industrial Revolution – have no option other than to acknowledge and commit to the role NRENs play in advancing science towards addressing the SDG (Sustainable Development Goals). For successful collaboration and direction, it is fundamental that policies within one country are aligned with one another. Alignment on continental level is crucial for the future Pan-African African Open Science Platform to be successful. Both the HIPSSA ((Harmonization of ICT Policies in Sub-Saharan Africa)3 project and WATRA (the West Africa Telecommunications Regulators Assembly)4, have made progress towards the regulation of the telecom sector, and in particular of bottlenecks which curb the development of competition among ISPs. A study under HIPSSA identified potential bottlenecks in access at an affordable price to the international capacity of submarine cables and suggested means and tools used by regulators to remedy them. Work on the recommended measures and making them operational continues in collaboration with WATRA. In addition to sufficient bandwidth and connectivity, high-performance computing facilities and services in support of data sharing are also required. The South African National Integrated Cyberinfrastructure System5 (NICIS) has made great progress in planning and setting up a cyberinfrastructure ecosystem in support of collaborative science and data sharing. The regional Southern African Development Community6 (SADC) Cyber-infrastructure Framework provides a valuable roadmap towards high-speed Internet, developing human capacity and skills in ICT technologies, high- performance computing and more. The following countries have been identified as having high-performance computing facilities, some as a result of the Square Kilometre Array7 (SKA) partnership: Botswana, Ghana, Kenya, Madagascar, Mozambique, Mauritius, Namibia, South Africa, Tunisia, and Zambia. More and more NRENs – especially the Level 6 NRENs 8 (Algeria, Egypt, Kenya, South Africa, and recently Zambia) – are exploring offering additional services; also in support of data sharing and transfer. The following NRENs already allow for running data-intensive applications and sharing of high-end computing assets, bio-modelling and computation on high-performance/ supercomputers: KENET (Kenya), TENET (South Africa), RENU (Uganda), ZAMREN (Zambia), EUN (Egypt) and ARN (Algeria). Fifteen higher education training institutions from eight African countries (Botswana, Benin, Kenya, Nigeria, Rwanda, South Africa, Sudan, and Tanzania) have been identified as offering formal courses on data science. In addition to formal degrees, a number of international short courses have been developed and free international online courses are also available as an option to build capacity and integrate as part of curricula. The small number of higher education or research intensive institutions offering data science is however insufficient, and there is a desperate need for more training in data science. The CODATA-RDA Schools of Research Data Science aim at addressing the continental need for foundational data skills across all disciplines, along with training conducted by The Carpentries 9 programme (specifically Data Carpentry 10 ). Thus far, CODATA-RDA schools in collaboration with AOSP, integrating content from Data Carpentry, were presented in Rwanda (in 2018), and during17-29 June 2019, in Ethiopia. Awareness regarding Open Science (including Open Data) is evident through the 12 Open Science-related Open Access/Open Data/Open Science declarations and agreements endorsed or signed by African governments; 200 Open Access journals from Africa registered on the Directory of Open Access Journals (DOAJ); 174 Open Access institutional research repositories registered on openDOAR (Directory of Open Access Repositories); 33 Open Access/Open Science policies registered on ROARMAP (Registry of Open Access Repository Mandates and Policies); 24 data repositories registered with the Registry of Data Repositories (re3data.org) (although the pilot project identified 66 research data repositories); and one data repository assigned the CoreTrustSeal. Although this is a start, far more needs to be done to align African data curation and research practices with global standards. Funding to conduct research remains a challenge. African researchers mostly fund their own research, and there are little incentives for them to make their research and accompanying data sets openly accessible. Funding and peer recognition, along with an enabling research environment conducive for research, are regarded as major incentives. The landscape report concludes with a number of concerns towards sharing research data openly, as well as challenges in terms of Open Data policy, ICT infrastructure supportive of data sharing, capacity building, lack of skills, and the need for incentives. Although great progress has been made in terms of Open Science and Open Data practices, more awareness needs to be created and further advocacy efforts are required for buy-in from African governments. A federated African Open Science Platform (AOSP) will not only encourage more collaboration among researchers in addressing the SDGs, but it will also benefit the many stakeholders identified as part of the pilot phase. The time is now, for governments in Africa, to acknowledge the important role of science in general, but specifically Open Science and Open Data, through developing and aligning the relevant policies, investing in an ICT infrastructure conducive for data sharing through committing funding to making NRENs financially sustainable, incentivising open research practices by scientists, and creating opportunities for more scientists and stakeholders across all disciplines to be trained in data management.