bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of wake characteristics behind an oscillating NACA 0012 airfoil in deep dynamic stall regime
Authors: D. Surekha Rathi Samundi , R. Rajasekar 
Published: January 2022

Purpose
This study aims to investigate the wake behind an oscillating airfoil at a various angle of incidence and Reynolds number in a deep dynamic stall condition.

Design/methodology/approach
NACA 0012 airfoil is allowed to undergo harmonic pitching motion about the quarter chord axis at Reynolds numbers of 0.5 * 105, 1.17 * 105, 1.7 * 105 and 2.12 * 105, and the reduced frequency of 0.1. The experiments are conducted at a set of mean and amplitude angle of attack that covered the angle of incidence from −5° to 25°. The wake rake is placed at a distance of one chord from the trailing edge of the airfoil.

Findings
The hysteresis of the flow during the upstroke and the downstroke motion are captured. The huge growth in the velocity defect and the wake thickness beyond the angle of attack of 15° explicate the appearance of the strong unsteady effects on the wake. The results also show that at the reduced frequency of 0.1, the wake structure is of drag producing type due to the momentum deficit.

Originality/value
Streamwise velocity profile and the turbulent intensity profiles are presented to show the effects of Reynolds number and angle of incidence on the wake behind the oscillating airfoil at the reduced frequency of 0.1, and in the intermediate range of Reynolds number is the novelty of the study.
Steady state solution of NFC model with nonlinear load using PEEC
Authors: Kvasnicka Samuel , Bauernfeind Thomas , Baumgartner Paul , Torchio Riccardo 
Published: January 2022

Purpose
The purpose of this paper is to show that the computation of time-periodic signals for coupled antenna-circuit problems can be substantially accelerated by means of the single shooting method. This allows an efficient analysis of nonlinearly loaded coupled loop antennas for near field communication (NFC) applications.

Design/methodology/approach
For the modelling of electrically small coupled field-circuit problems, the partial element equivalent circuit (PEEC) method shows to be very efficient. For analysing the circuit-like description of the coupled problem, this paper developed a generalised modified nodal analysis (MNA) and applied it to specific NFC problems.

Findings
It is shown that the periodic steady state (PSS) solution of the resulting differential-algebraic system can be computed very time efficiently by the single shooting method. A speedup of roughly 114 to conventional transient approaches can be achieved.

Practical implications
The proposed approach appears to be an efficient alternative for the computation of time PSS solutions for nonlinear circuit problems coupled with discretised conductive structures, where the homogeneous solution is not of interest.

Originality/value
The present paper explores the implementation and application of the shooting method for nonlinearly loaded coupled antenna-circuit problems based on the PEEC method and shows the efficiency of this approach.
Electrical power components decomposition of periodic polyharmonic current
Authors: Bialobrzheskyi Oleksii V. , RodKin Dmytro , Gladyr Andrii 
Published: January 2022

Purpose
At the current stage of electrical technology development, it is relevant to take into account the quality of electrical energy. It can be implemented if an assessed energy quality indicator is available. The amount of electrical energy is determined by active power, which is transmitted over a certain time period. In some cases, reactive power is included in the metering system. The distortion power is justifiably criticized and is not taken into account. The purpose of this paper consists in the substantiation of the indicator of the distortion of the periodic polyharmonic current electrical energy power, by separating from the instantaneous power such harmonics, which formed by same frequencies current and voltage harmonics.

Design/methodology/approach
Using the method of calculating linear polyharmonic current circuits, the following quantities are identified in instantaneous power: active, reactive and apparent powers of each harmonic. These components are known from references as canonical.

Findings
By the method of instantaneous power harmonic analysis, the components formed by current and voltage harmonics of the same frequency and different frequencies are distinguished.

Research limitations/implications
The RMS value of the instantaneous power due to current and voltage harmonics of different frequencies is justified in the work. This quantity allows you to distinguish the instantaneous power distortion level in comparison with the existing quantity.

Practical implications
The results can be used to assess the level of instantaneous power distortion level in commercial and technical metering systems.

Originality/value
The definition of instantaneous power distortion by extracting the canonical components from it and determining the root mean square value of the remainder is proposed.
Library anxiety among undergraduates in Nigeria
Authors: Adeeko Christy Olabisi , Adetimirin Airen 
Published: January 2022

Purpose
Library anxiety is a phenomenon that is different from other academic anxiety, which has implication on physical use of libraries. This study aims to investigate the phenomenon of library anxiety among undergraduates in federal universities in North-central, Nigeria.

Design/methodology/approach
Descriptive survey of the correlational type was adopted for the study. Purposive sampling technique was used in selecting five conventional federal universities, three homogenous faculties and six departments through multistage sampling technique. Five percent of the undergraduates (797) were selected from a total sample of 15,933. The instrument used was measuring scale on library anxiety (MSLA) developed by Bostick (1992). Descriptive statistics such as percentage mean and standard deviation were used to analyse the research questions.

Findings
The findings revealed that majority of the undergraduates (85.0%) experienced moderate level of library anxiety across the universities at varying degree. The most prevalent aspect of the library anxiety experienced by the undergraduates was inadequate knowledge of the library (x. = 2.14).

Research limitations/implications
The study selected five conventional universities out of the seven federal universities in North-central, Nigeria.

Originality/value
Based on the findings, the study recommends library orientation programme for the undergraduates to increase their knowledge of the library. Likewise, the library staff should be more approachable and friendly so as to alleviate the library anxiety experienced by the undergraduates.
Inbound tourism demand elasticities of MENA countries: the role of internal and external conflicts
Authors: Usman Ojonugwa , Alola Andrew Adewale , Ike George 
Published: February 2022

PurposeIn this paper, the authors investigate the inbound tourism demand elasticities of the Middle East and North African (MENA) countries. The authors emphasize the role of external and internal conflicts, world gross domestic product and relative prices over the period 1995–2017.Design/methodology/approachThis study applies the heterogeneous panel data estimators based on the fully modified-OLS (FM-OLS), dynamic-OLS (DOLS) and the recently developed method of moments quantile regression (MMQR).FindingsThe empirical results indicate that the effect of external and internal conflicts on inbound tourism demand is negative and inelastic with external conflict having a stronger effect. The effect of both classifications of conflicts diminishes as the market share of the tourist destination increases. In addition, the role of the world GDP on tourism demand is positive and elastic, suggesting that tourism is a luxury good while an increase in relative prices diminishes inbound tourism demand.Originality/valueThe paper, therefore, concludes that if policy measures are not put in place to curtail incidences of conflicts, economic growth in these countries may suffer setbacks. This by implications could affect the attainment of the sustainable development goals (SDGs) targets.
Firm absorptive capacity: multidimensionality, drivers and contextual conditions
Authors: Hussain Nazim , Bhatti Waheed Akbar , Khan Sana Akbar , Arslan Ahmad , Tarba Shlomo Yedidia 
Published: January 2022

Purpose
This paper aims to enrich absorptive capacity literature by specifically highlighting and adding environmental conditions and internationalisation process to the original conceptualisation.

Design/methodology/approach
The authors undertake a conceptual analysis and present an enhanced framework of absorptive capacity by integrating multiple literature streams. The authors have analysed the most relevant literature to provide underlying justifications for the proposed conceptual model.

Findings
Absorptive capacity ensures the long-term survival and success of a business. To develop absorptive capacity successfully, firms should focus on its various dimensions and existing intangible assets and external environment. The multidimensionality and richness of absorptive capacity is an under-explored area in the existing literature. The authors revisit the conceptualisation of absorptive capacity and add environmental conditions and the internationalisation process to the original conceptualisation. Absorptive capacity does not lead to a competitive advantage independent of its environment. To successfully develop it, firms have to adopt a holistic approach by considering the multi-dimensions, drivers and contextual conditions of absorptive capacity.

Originality/value
This study contributes by conceptualising absorptive capacity as a dynamic capability. It is one of the first studies to specifically propose a framework that combines antecedents (prior knowledge, combinative capabilities and IT capabilities), moderators (environmental conditions, namely, market and technological turbulence, competitiveness and the internationalisation process) and consequences (competitive advantage). The study offers a unique conceptualisation with implications for researchers and managers. As a result, managers will have a well-defined blueprint to create value by using firm capabilities.
Pursuing ways to improve the Brazilian procurement system: a comparison between the framework agreements in the United Kingdom and the Brazilian price registration system
Authors: Sorte Junior Waldemiro Francisco 
Published: January 2022

Purpose
The purpose of this paper is to conduct a literature review on framework agreements, an instrument for demand aggregation adopted in the UK, to recommend improvements to the price registration system (SRP), a mechanism often used with reverse online auctions in Brazil envisaged to promote more flexibility in centralized tenders, allowing public bodies to establish contracts when the need arises, based on registered prices.

Design/methodology/approach
A literature review was undertaken to analyze the UK framework agreement approach and the Brazilian SRP. In addition, in-depth interviews with civil servants from the Brazilian Ministry of Economy were conducted to examine the SRP.

Findings
The experience with framework agreements in the UK reveals at least four ways to improve the Brazilian SRP: i) extending the legal maximum duration of a price registration minute (ARP) ; ii) allowing the registration of additional suppliers in the ARP, instead of only the first lowest bidder; iii) conducting mini-competitions when a contracting authority decides to use the ARP to enter into a contract; and iv) including additional criteria for awarding suppliers, in line with the most economically advantageous tender (MEAT) approach.

Social implications
The flow of government financial resources into procurement accounted for approximately 16.5% of gross domestic product in Brazil and for an average of 12% in OECD countries in 2017 (OECD, 2019: 135). Public procurement is a strategic function for enabling an efficient public services delivery and infrastructure deployment. It is, therefore, relevant to examine instruments of demand aggregation to improve the outcomes of public procurement.

Originality/value
Framework agreements are currently not used in Brazil. This paper examines the UK experience with framework agreements to propose potential improvements to the Brazilian SRP, a procurement instrument vastly used in the country.
Accommodating guests during pandemic times: a case-study of the Airbnb Host Community in Aarhus, Denmark
Authors: Fischer Simon Lind , Roelofsen Maartje 
Published: February 2022

PurposeThis paper explores how Airbnb hosts' experiences with and responses to the coronavirus disease 2019 (COVID-19) health crisis may differ according to their motivations to host and to the type and spatial layout of their Airbnb accommodation. Based on these insights, the paper reflects on the lessons that are learned for the future of short-term rentals.Design/methodology/approachThis is a qualitative multi-method small-scale case study, which relies on in-depth interviews and a focus group discussion carried out with a group of hosts affiliated to the Airbnb Host Community in Aarhus, Denmark. Informed by an interpretivist approach, the study aims to make sense of people's subjective experiences with hosting on the Airbnb platform, and how they have continued and adapted their hospitality practices during the pandemic.FindingsParticipants' adaptive practices vary according to their motivations to host and the type of accommodation that they rent out. Although all hosts in this study now implement more intensive cleaning practices, hosts who stay with their guests onsite tend to take stricter preventative measures to avoid contamination and transmission of the virus in their social interactions with guests. On the contrary, hosts who rent out their entire properties and have minimal contact with their guests found themselves less affected by the pandemic's impacts and have had a continued demand for their properties.Social implicationsThe COVID-19 pandemic has unevenly affected Airbnb hosts. Hosts who share their homes with guests require different adaptations to their daily behaviour and cleaning practices at home than hosts who do not stay with their guests and rent out entire properties. However, unlike professional hosts who largely or solely rely on Airbnb for their income, occasional home-sharing hosts tend to be more flexible in coping with cancelled or fewer bookings.Originality/valueThis study provides novel insights into the uneven impact of the COVID-19 pandemic on participants in the platform economies of tourism. It contributes to existing literature on the impacts of the pandemic on Airbnb's operations by showing how hosts' adaptive practices are informed by their subjective living conditions and the type of accommodation they can offer their guests.
What might happen to the global stock market after Brexit?
Authors: Ren Zhiyuan 
Published: February 2022

Purpose
The stock market is vulnerable to various exogenous factors, and its fluctuations can reflect the effects of political, economic and market factors. The purpose of this paper is therefore to choose the stock market as a representative to analyze the potential impact of the Brexit event on global financial markets and how to prevent the spread of risks across global financial markets.

Design/methodology/approach
This study chooses the auto-regressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model to fit the financial series and uses it as the marginal distribution model to establish the vine copula model. The maximum spanning tree algorithm is used to select the optimal rattan structure model and pair-copula function. According to the final ARMA-GARCH-R-vine copula model, the tail correlation coefficients of the UK, France, Germany, USA and China stock markets are calculated and used to analyze their dependence structure.

Findings
The negative impact of the Brexit event on the British stock market is greater and is more likely to be transmitted to France and Germany. China and the USA are less likely to be impacted by the Brexit incident. The US financial market is more closely linked to France, and it may benefit from the Brexit incident due to the impact of the exchange rate. Although the Chinese stock market is directly connected to the British stock market, due to the existence of national macro-controls and other factors, it will be less affected by the Brexit incident. The main impact comes from the dual devaluation pressure on the RMB.

Originality/value
This paper selects the optimal combination model based on actual data, and the results obtained can accurately reflect the interdependence between relevant stock markets and can guide risk aversion in the financial investment field.
Discrimination of electrical tapes using ATR‐FTIR spectroscopy and chemometrics
Authors: Nimi Chongtham , Chophi Rito , Singh Rajinder 
Published: February 2022

AbstractElectrical tapes are recovered during criminal investigations as physical evidence in cases of rape, kidnapping, and explosion incidents. The analysis of such evidence can provide an evidentiary link between the suspect, the victim, object, or the crime scene. In the present study, 25 brands of electrical tapes have been analyzed using ATR‐FTIR (attenuated total reflectance Fourier transform infrared) spectroscopy. Samples (1 cm2) were analyzed in the mid IR (Infrared) region from 4000–600 cm−1, and the functional groups of various components have been profiled. Chemometric methods‐PCA (principal component analysis) and PCA‐LDA (linear discriminant analysis) have been employed to interpret the data and classify the samples into its respective classes. Preliminary assessment of sample clustering due to similar chemical composition was visualized using PCA. PCA‐LDA applied for classification purpose yielded classification accuracy (calibration) of 92.98% for the adhesive side and 88% for the backing side. The validation results showed classification accuracy of 89.47% for the adhesive side and 84% for the backing side. Blind validation study was carried out using 5 samples, and classification accuracy of 100% and 80% was obtained for the adhesive and the backing side, respectively. In the current study, a preliminary substrate study was carried out, and the results showed that the backing samples could be more accurately matched to their correct source of origin than the adhesive side.
The impact of cost stickiness on financial reporting: evidence from income smoothing
Authors: Hartlieb Sven , Loy Thomas R. 
Published: January 2022

AbstractThis study investigates the impact of cost stickiness on income smoothing. Prior literature at the intersection between management and financial accounting has understood changes in cost behaviour as mere consequences of short‐term earnings management incentives. By considering income smoothing as the more complex earnings management strategy, we argue that resource adjustment strategies underlying cost behaviour might also have an impact on long‐term financial reporting choices. Specifically, asymmetric reactions of costs to sales changes should increase earnings volatility and thus restrict managers’ capabilities to report smooth income streams, which is supported by our empirical results. Additional tests reveal that cost stickiness primarily restricts opportunistic income smoothing and that the relationship depends on other factors such as the level of adjustment costs.
Comparative analysis between extra‐short implants (≤6 mm) and 6 mm‐longer implants: a meta‐analysis of randomized controlled trial
Authors: Fernandes GVO , Costa BMGN , Trindade HF , Castilho RM , Fernandes JCH 
Published: January 2022

ABSTRACTThe goal of this systematic study was to compare the survival rate (SR), marginal bone loss (MBL) and clinical complications between extra‐short implants (≤6 mm) and 6‐mm‐longer implants in randomized clinical trials. A systematic electronic and manual search was performed using the PubMed, Web of Science, Scopus and DOAJ databases. A meta‐analysis was conducted to compare the SR and MBL between both groups. We have selected 17 studies out of 1016 articles for qualitative and quantitative analysis. The data from 956 patients and 1779 implants were used with an overall mean clinical follow‐up of 3.88 years ranging from 1 to 8 years. Overall, the SR of extra‐short implants (93.12%) was lower than the observed in 6‐mm‐longer implants (95.98%); however, there was no statistical significance on these findings (P > 0.10). MBL analysis showed that extra‐short implants and the 6‐mm‐longer group presented an average of −0.71 and −0.92 mm after 1‐year respectively. Three years follow‐up showed MBL of −0.42 mm (≤6 mm) and −0.43 mm (>6 mm); 5 years follow‐up showed an MBL of −0.69 mm (≤6 mm) and −0.46 mm (>6 mm); and after 8 years of follow‐up, it was found an MBL of −1.58 mm (≤6 mm) and −2.46 mm (>6 mm). Within the limitation of this study, the results indicated that SR of extra‐short implants was similar to 6‐mm‐longer implants. In contrast, MBL and the presence of clinical complications were observed at a lessened rate on extra‐short implants.
Characterization of eosinophilic esophagitis variants by clinical, histological, and molecular analyses: A cross‐sectional multi‐center study
Authors: Greuter Thomas , Straumann Alex , Fernandez‐Marrero Yuniel , Germic Nina , Hosseini Aref , Yousefi Shida , Simon Dagmar , Collins Margaret H. , Bussmann Christian , Chehade Mirna , Dellon Evan S. , Furuta Glenn T. , Gonsalves Nirmala , Hirano Ikuo , Moawad Fouad J. , Biedermann Luc , Safroneeva Ekaterina , Schoepfer Alain M. , Simon Hans‐Uwe 
Published: January 2022

AbstractObjectivePhysicians are increasingly confronted with patients presenting with symptoms of esophageal dysfunction resembling eosinophilic esophagitis (EoE), but absence of significant esophageal eosinophilia. The purpose of this study was to characterize and classify this group of EoE variants.DesignPatients from six EoE‐centers with symptoms of esophageal dysfunction, but peak eosinophil counts of <60/mm2 (<15/hpf) in esophageal biopsies and absence of gastro‐esophageal reflux disease (GERD) were included. Clinical, endoscopic, (immuno)‐histological, and molecular features were determined and compared with EoE, GERD, and healthy controls.ResultsWe included 69 patients with EoE variants. Endoscopic abnormalities were found in 53.6%. We identified three histological subtypes: EoE‐like esophagitis (36/69, 52.2%), lymphocytic esophagitis (14/69, 20.3%), and non‐specific esophagitis (19/69, 27.5%). Immunohistochemistry revealed—in contrast to EoE—no significant increase in inflammatory cell infiltrates compared with GERD and healthy controls, except for lymphocytes in lymphocytic esophagitis. EoE‐typical Th2‐response was absent in all EoE variants. However, considerable structural changes were detected based on histology and protein expression. Using next generation mRNA sequencing, we found the three EoE variants to have distinct molecular fingerprints partially sharing pronounced traits of EoE. Hierarchical sample clustering of RNA sequencing data confirmed the presence of an EoE‐like (characterized by eotaxin‐3 expression), non‐specific, and lymphocytic variant cluster (characterized by CD3 cells and TSLP expression).ConclusionAll EoE variants are clinically and histologically active conditions despite the absence of esophageal eosinophilia. EoE variants appear to be part of a disease spectrum, where classical EoE represents the most common and apparent phenotype.