bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Advances in Wide Bandgap Perovskite Solar Cells: Focus on Lead‐Free Materials for Tandem Structures
Authors: Jang Won Jin , Jang Ho Won , Kim Soo Young 
Published: May 2023

AbstractA tandem solar cell, which is composed of a wide bandgap (WBG) top sub‐cell and a narrow bandgap (NBG) bottom subcell, harnesses maximum photons in the wide spectral range, resulting in higher efficiency than single‐junction solar cells. WBG (>1.6 eV) perovskites are currently being studied a lot based on lead mixed‐halide perovskites, and the power conversion efficiency of lead mixed‐halide WBG perovskite solar cells (PSCs) reaches 21.1%. Despite the excellent device performance of lead WBG PSCs, their commercialization is hampered by their Pb toxicity and low stability. Hence, lead‐free, less toxic WBG perovskite absorbers are needed for constructing lead‐free perovskite tandem solar cells. In this review, various strategies for achieving high‐efficiency WBG lead‐free PSCs are discussed, drawing inspiration from prior research on WBG lead‐based PSCs. The existing issues of WBG perovskites such as VOC loss are discussed, and toxicity issues associated with lead‐based perovskites are also addressed. Subsequently, the natures of lead‐free WBG perovskites are reviewed, and recently emerged strategies to enhance device performance are proposed. Finally, their applications in lead‐free all perovskite tandem solar cells are introduced. This review presents helpful guidelines for eco‐friendly and high‐efficiency lead‐free all perovskite tandem solar cells.
Bio‐Inspired Subnanofluidics: Advanced Fabrication and Functionalization
Authors: Hou Jue , Zhao Chen , Zhang Huacheng 
Published: May 2023

AbstractBiological ion channels can realize high‐speed and high‐selective ion transport through the protein filter with the sub‐1‐nanometer channel. Inspired by biological ion channels, various kinds of artificial subnanopores, subnanochannels, and subnanoslits with improved ion selectivity and permeability are recently developed for efficient separation, energy conversion, and biosensing. This review article discusses the advanced fabrication and functionalization methods for constructing subnanofluidic pores, channels, tubes, and slits, which have shown great potential for various applications. Novel fabrication methods for producing subnanofluidics, including top‐down techniques such as electron beam etching, ion irradiation, and electrochemical etching, as well as bottom‐up approaches starting from advanced microporous frameworks, microporous polymers, lipid bilayer embedded subnanochannels, and stacked 2D materials are well summarized. Meanwhile, the functionalization methods of subnanochannels are discussed based on the introduction of functional groups, which are classified into direct synthesis, covalent bond modifications, and functional molecule fillings. These methods have enabled the construction of subnanochannels with precise control of structure, size, and functionality. The current progress, challenges, and future directions in the field of subnanofluidic are also discussed.
HF‐Free Microwave‐Assisted Synthesis of Nano‐Micro‐Sized K2SiF6:Mn4+ for MicroLED Color Conversion
Authors: Tian Houdao , Seto Takatoshi , Wang Yuhua 
Published: May 2023

AbstractMicro‐light‐emitting diodes (MicroLED) are considered to be the next generation of ideal display devices, with chip size requirements of less than 50 µm. To meet its micron‐scale pixel size, submicron luminescent materials are needed. Mn4+ doped fluoride phosphor, K2SiF6:Mn4+(KSFM) as a red luminescent material with excellent narrow‐band emission sensitivity to human eyes, has great potential as a color conversion material for full‐color MicroLED. However, it is difficult to obtain small‐size KSFM efficiently by conventional synthesis methods. Here, a simple HF‐free strategy for the rapid batch synthesis of nano‐micro‐sized KSFM based on a microwave‐assisted method is reported. The synthesized KSFM shows uniform morphology, average particle size is less than 0.2 µm, and has 89.3% internal quantum efficiency under 455 nm excitation. It exhibits excellent thermal stability (97.4%@423 K of the integrated emission intensity at 298 K) and prominent moisture resistance (81.9% of its initial relative emission intensity after immersing in water for 30 min). By employing it as a red emitter, the authors fabricate high‐performance white LEDs with high luminous efficacy of 116.1 lm W−1 and wide color gamut of 130.4% NTSC. In addition, self‐luminous red‐emitting arrays with a pixel size of 20 × 40 µm are constructed by nanoimprinting as‐synthesized KSFM.
Mean stress effect in high‐frequency mechanical impact (HFMI)‐treated welded steel railway bridges
Authors: Al‐Karawi Hassan , Shams‐Hakimi Poja , Pétursson Hans , Al‐Emrani Mohammad 
Published: May 2023

AbstractThe need for new railway bridges is driven by the growing volume of transportation demands for both passenger and freight traffic on railway networks. In the design of these bridges, the fatigue limit state is a criterion that usually limits the allowable applied load level and thus also the utilization of the high strength of the steel material. Therefore, improving the fatigue performance of welded details by high‐frequency mechanical impact (HFMI) treatment leads to a more efficient design. However, the fatigue performance of HFMI‐treated welds is known to be affected by the mean stress and this needs to be considered in the design of treated welded details in steel bridges. This is rather straightforward if the bridge is subjected to cycles from one type of train but becomes cumbersome when several different sets of trains (e. g. axle loads, axle distances) cross the bridge. In this article, a factor to take the mean stress effect (including self‐weight and traffic load variations) into account is derived from traffic data measured in Sweden. Moreover, the mean stress effect is also predicted using the different fatigue load models in the Eurocode. These models either consist of one‐load patterns such as LM71, SW/0, and SW/2 or are composed of different trains with different combinations. It was found that the mean stress effect is underestimated by the first group of models. On the other hand, the mean stress predicted by the light traffic mix is found to be close to that calculated using real traffic data, while other mixes (standard and heavy) underestimate the mean stress effect. Therefore, a correction factor to account for the mean stress effects in real traffic is derived (called here λHFMI). This factor can be used to correct the design stress range for fatigue verification of HFMI‐treated welded details in railway bridges.
Forecasting the impact of meteorological parameters on air pollutants in Andhra Pradesh using machine learning techniques
Authors: Teja Kambhampati , Mozumder Ruhul Amin , Laskar Nirban 
Published: May 2023

AbstractIn the 21st century, air pollution has emerged as a significant problem all over the globe due to a variety of activities carried out by humans, such as the acceleration of industrialization and urbanization. SO2, NO2, and NH3 are the key components contributing to air pollution. Moreover, these air pollutants have a significant connection to several climatic characteristics, such as the speed of the wind, the relative humidity, the temperature, the amount of precipitation, and the surface pressure. As a result, machine learning (ML) is regarded as a more effective strategy for predicting air quality than more conventional approaches such as probability and statistics, among others. In the research, Decision Tree (DT), Support Vector Regression (SVR), Random Forest (RF), and Multi‐Linear Regression (MLR) algorithms are used to make predictions about air quality, and MSE (Mean Squared Error), RMSE (Root Mean Square Error), MAE (Mean Squared error), and R2 are used to determine how accurate the predictions are.
Toward a green economy: The nexus between economic and environmental factors in MENA countries, ARDL bounds approach
Authors: Idris Fawzia Mohammed , Seraj Mehdi , Ozdeser Huseyin 
Published: May 2023

AbstractWith the transition of the global economy toward a green economy, it is important to analyze the elements that can either support or impede this transformation. Therefore, in this study, we aimed to evaluate the potential of the green economy in the Middle East and North Africa (MENA) countries by analyzing the correlation between economic and environmental factors. The objective of this study is to explore the potential of the green economy in MENA countries by analyzing key factors such as access to clean fuel, GDP, and CO2 emissions. The study aims to distinguish between long‐ and short‐term effects, assess the presence of a long‐run relationship or co‐integration between the parameter estimates, and evaluate the progress of MENA countries toward a green economy based on the impact of economic, and environmental factors. Using quarterly and seasonally adjusted data from 2000 to 2018, the auto‐regressive distributed lag (ARDL) technique was employed to examine the co‐integration of the factors in the long and short terms. Multiple cointegration techniques were also used to determine the feasibility of a green economy by analyzing the relationship between access to clean fuel for technology and cooking, GDP, and CO2 emissions. The study's findings indicate a clear long‐ and short‐term relationship between the analyzed factors, as confirmed by the error correction model (ECM) which suggests that the variables are cointegrated and potentially relevant. Additionally, the result of the autoregressive distributed lag bound test shows that the green economy variables, GDP, CO2 emissions, and access to clean fuel, are cointegrated in the long‐term.
Debridement and primary closure of a mesenteric duodenal perforation in a dog
Authors: Edwards Laura , Belda Beatriz , Risselada Marije 
Published: May 2023

AbstractA 7‐year‐old male mixed intact breed dog was presented with a 6‐day history of lethargy and anorexia. A linear foreign body was diagnosed and an exploratory laparotomy performed. The foreign body was pushed orad and removed via gastrotomy. Two mesenteric duodenal perforations were found: one at the level of the common bile duct and a second at the duodenal flexure. Both lesions were debrided and primarily closed in a simple interrupted appositional pattern. A gastrostomy tube and closed suction drain were placed routinely. The dog recovered without complications and ate voluntarily the first day postoperatively. The drain and gastrostomy tube were removed without incident at 4 and 15 days, respectively. Five months postoperatively the dog was reported to be clinically normal. Debridement and primary closure may represent an alternative to more extensive surgery with rerouting for duodenal perforations in select cases.
Data-Driven Development in Public Sector: How Agile Product Teams Maneuver Data Privacy Regulations
Authors: Barbala Astri , Sporsem Tor , Stray Viktoria 
Published: May 2023

AbstractDatafication processes, the ongoing strive for making organizations data-driven, have in recent years entailed data-focused software projects and more interdisciplinary teamwork. Simultaneously as agile product teams have been directed towards increased use of data for software development, stronger data protection regulations such as GDPR have further complexified the software developer role, whose responsibilities and expectations now expand far beyond mere coding. Seeking to develop an understanding of how data-intensive product teams in the public sector maneuver the legal hurdles emerging in the wake of data governance, this paper builds on 19 interviews with members of two agile product teams in the Norwegian organizations NAV and Entur. Our findings indicate that including a legal expert in the team can boost confidence in data handling practices and avoid delays in deliveries, but it requires effort to synchronize and overcome interdisciplinary barriers.
Real-Life Water-Scrum-Fall: Insights from Large Companies in Czech Republic
Authors: Křivánková Michaela , Remta Daniel 
Published: May 2023

AbstractBackground. A combination of traditional and agile methodologies into so-called “hybrid approaches” are today’s reality. The intention is to attempt maximization of benefits from both approaches. Water-Scrum-Fall is a methodology for hybrid approaches. However, there are no specific guidelines described for Water-Scrum-Fall. Aim. Explore and describe the reality of Water-Scrum-Fall in selected large companies in the Czech market. Method. Exploratory multiple-case study – four companies, eight participants. Semi-structured interviews and thematic analysis. Results. Insights into real-life Water-Scrum-Fall including involved roles, associated events, and typically created artifacts. Conclusion. In examined companies, modified agile methodologies are used as part of Water-Scrum-Fall, while their benefits are not fully unlocked due to poor implementations. However, project success rate is high. Hybrid approaches still require rigorous analysis before the development is started, which strongly limits the agility in the following development phase. Customer involvement or feedback loop is omitted in the development process. We accompany poor implementations with the unpreparedness of companies to fully adopt Agile, and missing senior roles, like scrum masters, to educate teams and organizations in proper agile practices.
A Novel Technique to Assess Agile Systems for Stability
Authors: Healy Robert , Dey Tapajit , Conboy Kieran , Fitzgerald Brian 
Published: May 2023

AbstractAgile systems, like the Kanban and Scrum frameworks, are built on assumptions of sustainability and stability, however, there is little empirical evidence on whether such systems are stable in practice or not. Therefore, in this study we aim to inspect the stability of Agile systems by leveraging the concept of stability described in Queueing Theory. We define a novel metric, the Stability Metric, as a way of assessing queueing systems, especially Agile systems. We inspect 926 Jira projects in 14 organizations with over 1.6 million product backlog items using this metric. The analysis showed that 72.89% of these Jira projects were not stable and stable systems, on average, had product backlog sizes 10 times shorter than unstable ones. These results suggest that while the goal of Agile is to create a sustainable, stable way of working, this is not guaranteed, and a better understanding of systems and queues may be required to help design, create, coach, and maintain optimal Agile systems.
A Lean Approach of Managing Technical Debt in Agile Software Projects – A Proposal and Empirical Evaluation
Authors: Aldaeej Abdullah , Nguyen-Duc Anh , Gupta Varun 
Published: May 2023

AbstractTechnical Debt Management (TDM) includes activities such as identifying, measuring, and prioritizing technical debt. It is mainly performed to proactively mitigate the risk of losing the maintainability and evolvability of the software product which results in reducing the team velocity. Despite the importance of TDM, its adoption in software companies remain limited. Software companies are witnessing high market demand and competition that make delivering customer value outweighs the effort invested in TDM activities. Since the impacts of technical debt are uncertain and evident only in the long run, it is more difficult for companies with very limited resources to proactively spend their resources on TDM. In this paper, we propose a lean approach to facilitate the adoption of TDM in software companies with very limited resources. Based on this approach, TDM is driven by project management metrics, such as team or sprint velocity, and velocity variance. We conducted an initial evaluation of the concept of this approach through a short survey of 43 software project/product managers. Most of the survey respondents have a positive impression about our approach, which will encourage us to proceed further using more robust empirical evaluation.
An Empirical Study About the Instability and Uncertainty of Non-functional Requirements
Authors: Viviani Luiz , Guerra Eduardo , Melegati Jorge , Wang Xiaofeng 
Published: May 2023

AbstractManaging non-functional requirements (NFRs) has been a challenge in software development for many years. These requirements are typically used to make important architectural decisions early in the project, which can be problematic if they are uncertain or unstable. When this uncertainty is not considered when designing the software architecture, changes are often costly and sometimes even unfeasible. Some empirical studies on the subject have already been carried out, but few have focused on the perspective of professionals with extensive experience on the changes and uncertainties of NFRs. This work aims to expand the understanding about the management, clarity and validation of NFRs to fill this gap in the literature. To achieve this goal, a survey was carried out with professionals to find out how NFRs were managed and validated. For the research design, instead of generic questions, the questionnaire focused on some specific types of NFRs to induce participants to recall and report concrete situations. As a result, 40 valid responses were obtained, most from professionals with more than 10 years of experience. The results reveal that a significant number of NFRs were defined after the delivery of software increments (more than 30%) and that revision and change occurred in about a third of the NFRs. Hence, this study presents evidence that NFRs, as the functional ones, can also be uncertain and change frequently, requiring agile approaches and techniques to evolve the software architecture to consider this uncertainty.
Striving for Freedom in a Large-Scale Agile Environment with an Entrepreneurial Mindset of a Product Owner
Authors: Niva Piret , Paasivaara Maria , Hyrynsalmi Sami 
Published: May 2023

AbstractIn a large-scale agile environment, a Product Owner receives requests from many different directions. Freedom to influence the direction of the product and push ideas forward sometimes requires saying “no”. This is a case study that has been made by interviewing several Product Owners or people working in a Product Owner type of role. The case company, which is a large financial organization, encourages Product Owners to take responsibility by valuing an entrepreneurial mindset. This research examines whether it is possible to exercise entrepreneurial freedom in the Product Owner’s work, and how much freedom the Product Owner has in the direction of the product, i.e. whether they have the freedom to say “no”. A total of 18 Product Owners, and those in similar roles, as well as managers from the case company, were interviewed. The findings show that the role of the Product Owner needs to be clarified in order to have more freedom to act. Prioritizing is difficult and saying “no” is more difficult than desired. Product Owners find the urge for an entrepreneurial attitude understandable, however, it does not seem to fit perfectly into the everyday work life of a Product Owner in a large-scale set-up. When the understanding of the role deepens, Product Owners could have greater freedom to make their products successful.
Sustaining Agility: Organizational Change, Factors and Theoretical Lenses
Authors: Barroca Leonor , Sharp Helen , Deshpande Advait , Gregory Peggy , Papadeas Stavros 
Published: May 2023

AbstractAgile organizations have to deal regularly with change and at the same time adapt to sustain agility. In this paper, we present an initial study to identify factors considered when changes need to be made to sustain agility. We used a novel data collection approach, critical decision method (CDM), and investigated three theoretical lenses, paradox theory, situation awareness and shared mental models, to explore the kind of practical consequences they help to uncover. This paper presents the findings of this initial study together with reflections on the data collection method and the three theoretical lenses. Three key dimensions relevant to sustaining agility emerge from the use of these theoretical lenses: teams vs organization; understanding the environment vs the impact of change internally; and understanding “now” vs looking into the future.
The Role of Responsiveness to Change in Large Onboarding Campaigns
Authors: Smite Darja , Moe Nils Brede 
Published: May 2023

AbstractOnboarding is a process of organizational socialization of the new hires, that includes recruitment, orientation, training, coaching and support. While onboarding individuals into an organization is a rather straightforward task, little is known about 1) onboarding hundreds of developers and 2) doing it on a distance in outsourcing situations. Furthermore, the subject of sustainable growth with respect to organizational capabilities and culture is often overlooked. This paper reports findings from an exploratory multi-case study of two large onboarding campaigns. We collected empirical data from interviews, retrospectives, onboarding documentation and onsite visits. Based on the empirical study, onboarding hundreds of software engineers in a complex agile product development environment which lacks documentation and puts high demands on engineers’ knowledge and skills is a challenging and costly endeavor. To save the costs and for practical reasons, large-scale onboarding is organized in batches with the first batch trained onsite, and the later batches trained internally. We report challenges faced in the two cases and discuss possible solutions. One core finding is that a good plan combined with the organizational agility, i.e., the responsiveness to change, together with organizational maturity determined the success of organizational scaling. The presented cases contribute to the scarce research on knowledge transfer and onboarding in a large-scale agile context.
Management von Komplexität am Beispiel von Covid-19
Authors: Lechleuthner Alexander 
Published: May 2023

ZusammenfassungDie Bekämpfung der Corona-Pandemie ist nicht nur kompliziert (das heißt in Teilen nur von Experten und Expertinnen verstehbar), sondern auch komplex (das heißt selbst von Experten und Expertinnen nur schwer prognostizierbar). In 2021 blieb die Corona-Pandemie mit den bis dahin bekannten Varianten in Deutschland unter anderem durch kontaktreduzierende Maßnahmen, die zusätzlich zu Basismaßnahmen (wie Masken oder AHA-L-Regeln) eingesetzt wurden, beherrschbar − auch bei einem steilen Anstieg der Krankenhausbelegung, die die intensivmedizinische Versorgung gefährdete.Dieses Kapitel kann natürlich im Kontext des sehr dynamischen Pandemiegeschehens (mit immer neuen Virusmutationen wie etwa der Omikron-Variante) nur eine Momentaufnahme darstellen.
Personalrisikomanagement und der Beitrag des ivwKöln
Authors: Arnold Rolf 
Published: May 2023

ZusammenfassungIn der wissenschaftlichen Auseinandersetzung mit dem Risikomanagement der Unternehmen stehen insbesondere finanzielle und technische Risiken im Vordergrund. Personal als eine wesentliche Ressource für den unternehmerischen Erfolg und die mit Personal verbundenen Risiken sind dagegen weniger Gegenstand des wissenschaftlichen Diskurses. Im Talentmanagementansatz lassen sich wesentliche Ansätze eines Risikomanagementansatzes aufzeigen. Für das Talentmanagement eines Unternehmens sind dabei auch externe Kooperationspartner relevant. Das Institut für Versicherungswesen (ivwKöln) fördert seit 50 Jahren als Kooperationspartner der Versicherungsbranche das Talentmanagement der Unternehmen in der Versicherungsbranche. Dadurch werden Beiträge zum Management der Personalrisiken, insbesondere in Verbindung mit der Akquisition, der Bindung und der Motivation von Personal geleistet.