Hasil untuk "Maps"

P. Sánchez, S. Ahamed, F. Carré et al.

A. Anderson, M. Bader, E. Bard et al.

Shengyuan Liang, Zhiqiang Jia, Rezia Emir et al.

Abstract Early breast cancer detection rates are low in Kashgar, Xinjiang, China, potentially due to poor spatial accessibility to diagnostic services. This study examined the association between travel burden from patient residences to hospitals and the stage of breast cancer at diagnosis in this population. We analyzed data from 981 female patients (aged > 20 years) diagnosed with breast cancer at the First People’s Hospital of Kashgar between 2019 and 2022. Driving distances were calculated using the Baidu Maps API. Multivariable multinomial and binary logistic regression models were used. 29.9% of the sample were diagnosed at an advanced stage of disease. Residing more than 20 km from secondary hospitals increased the relative risk of advanced-stage diagnosis by 1.61-fold (95% CI: 1.20–2.31, vs. early-stage) and the odds by 1.48 times (95% CI: 1.07–2.05, vs. non-advanced stage). Similarly, living more than 80 km from tertiary hospitals was associated with an elevated relative risk (RRR = 1.38; 95% CI: 1.08–1.75, vs. early-stage) and 1.40 times the odds (95% CI: 1.04–1.90, vs. non-advanced stage) of advanced-stage diagnosis. Longer travel distances to both secondary and tertiary hospitals are associated with increased risks of advanced-stage breast cancer at diagnosis in Kashgar. Enhancing spatial accessibility to diagnostic services is crucial for improving early detection and potentially downstaging breast cancer in this and similar remote regions.

Esteban Salizzi

The work introduces a collection of schemes and thematic maps that represent the transformation process driven through the advance of the modern agrarian frontier over the northern departments of the province of Córdoba (Río Seco, Sobremonte and Tulumba), Argentina, among the 1990s and 2015. The visual materials prepared, along with their respective comments, synthesize the diversity of factors and dynamics that converge in the territorial expansion of the agribusiness productive model in the region, seeking to offer a comprehensive view of the phenomenon. This is an initiative interested in the use of graphic tools to face the challenges established by the study of the advance of modern agrarian frontiers, as well as other fronts of capital expansion.

Satriagasa Muhammad Chrisna, Suryatmojo Hatma, Kusumandari Ambar et al.

Accurate land use information is vital for effective watershed monitoring and management. This study explores the use of ChatGPT-4o, a multimodal large language model (LLM), to interpret UAV-derived orthomosaics in the Tamansari Catchment, Central Java, Indonesia. High-resolution imagery from 2018 and 2025 was analyzed through natural language prompts to identify land use types and detect changes over time. Results revealed a significant shift toward intensive agriculture, with agroforestry decreasing from 32.3% to 4.8% and secondary forest cover halving from 19.4% to 9.7%. A hybrid validation strategy was applied, combining internal spatial consistency checks with external visual verification using Google Street View. While the method does not produce pixel-based classification maps, it enables descriptive interpretation without requiring advanced technical skills. The findings demonstrate that ChatGPT-4o can serve as a rapid, accessible, and cost-effective tool for participatory watershed monitoring, especially in data-scarce or low-resource environments. Further integration with ground-truth data is recommended to improve accuracy.

Anna Szychta

Dear Authors and Readers,The closing issue of “Zeszyty Teoretyczne Rachunkowości” (ZTR, “The Theoretical Journal of Accounting”) for 2025, vol. 49, number 4, once again provides an engaging and multidimensional review of contemporary research trends in accounting. This Special Issue, titled Contemporary challenges, conditions and directions of development of accounting, gathers 13 studies that explore the ongoing transformation of the accounting discipline driven by technological advancements, sustainability demands, and evolving expectations from professionals and educators. The featured articles reflect a diverse range of approaches, from theoretical modelling and comparative analysis to bibliometric synthesis and empirical evaluation, offering a comprehensive perspective on the accounting field as it advances into a new digital and regulatory era.At the intersection of behavioural finance and accounting communication, Adeel Ali Qureshi and Mateusz Lemańczyk present a comprehensive literature review in their paper Attention metrics and stock market reactions to accounting events: A literature review. By combining bibliometric analysis with the TCCM frame- work, they investigate how investor attention, measured by media coverage, online search activity, and textual complexity, influences market reactions to accounting disclosures. Their findings highlight the increasing significance of behavioural insights and data analytics in understanding how financial information is perceived, processed, and priced.The paper by Mateja Brozović, Sanja Sever Mališ, and Dominik Piršić, titled Financial accounting analysis of leverage and profitability: Evidence from Croatian SMEs, expands the discussion to corporate financial performance. Using key financial ratios from small and medium-sized enterprises in Croatia, the authors analyse the relationship between leverage and profitability, providing empirical evidence that enhances understanding of the financial resilience and risk structures of SMEs, a vital yet often overlooked segment of the European economy.Renáta Hornická and Renáta Pakšiová examine the development of non-financial disclosure in their paper Scope of sustainability reporting in the largest companies in Slovakia in 2017 and 2022. By analysing textual data from the annual and sustainability reports of major Slovak firms, they document a noticeable growth in the scope and depth of ESG reporting following the introduction of the Non-Financial Reporting Directive. Their findings offer timely insight into how regulatory pressure drives increased corporate accountability and the institutionalisation of sustainability reporting in Central and Eastern Europe.A broader institutional and regulatory perspective on sustainability assurance is examined by Tanja Laković, Daniel Zdolšek, and Milica Vukčević in their paper Development of the regulatory framework for sustainability assurance: A comparative analysis of the transition from NFRD to CSRD in Slovenia and Montenegro. This comparative study highlights the challenges and opportunities of implementing the new EU Corporate Sustainability Reporting Directive in Montenegro, a non-EU member state. It highlights differences in readiness and institutional adaptation between EU member and candidate countries.From a theoretical perspective, Serhii Lehenchuk and Viktoriia Makarovych offer an innovative conceptual discussion in Theoretical foundations of accounting for intellectual investment property: Towards standard setting. Their paper develops a framework for recognising and measuring intellectual investment property, bridging gaps between traditional accounting and emerging forms of intangible capital. By proposing theoretical principles for potential standardisation, the study adds a significant perspective to debates on accounting for knowledge-based assets in the digital economy.The linguistic and communicative aspects of accountability are examined in Raili Lilo, Elina Paemurru, and Ülle Pärl’s paper, Accountability through linguistic features: A holistic theoretical framework for sustainability reports. Through a meta- -analysis of previous empirical studies, the authors incorporate insights from legitimacy, stakeholder, signalling, and institutional theories to illustrate how language can both promote and conceal accountability in sustainability reporting. Their comprehensive framework offers a valuable basis for analysing how textual choices such as tone, clarity, and structure can influence stakeholders’ perceptions of corporate responsibility and transparency.The public sector perspective is presented by Diana Papradanova and Ventsislav Vechev in their paper An evaluation of the accounting model for reporting public sector entities’ revenues in Bulgaria in the context of the International Public Sector Accounting Standards. The authors carry out a detailed comparative analysis of Bulgarian regulations and IPSAS provisions, highlighting conceptual differences and gaps that impede transparency and comparability. Their findings offer practical recommendations for aligning public-sector accounting practices with international standards and fiscal accountability principles.The human factor and digital transformation in accounting are central themes in Katarzyna Prędkiewicz and Krzysztof Biegun’s article, Factors that influence accountants’ acceptance of Artificial Intelligence: An extended Technology Acceptance Model, which incorporates technology anxiety and experience. The authors empirically expand the Technology Acceptance Model by including variables related to technological anxiety and professional experience, offering fresh insights into how accountants view, accept, and adopt AI tools in their work. Their findings emphasise both the opportunities and psychological barriers in the move towards automation and intelligent systems in accounting practice.The contribution by Ana Rep Romić, Marzena Remlein, and Sanja Sever Mališ, titled Information technology in accounting education: A bibliometric-systematic literature review (2006–2025), focuses on the intersection of pedagogy and digitalisation. Drawing on a bibliometric and systematic literature review spanning two decades of research, the authors map global trends in the integration of IT into accounting education. Their study identifies emerging competencies, evolving educational technologies, and the changing role of educators in developing digitally literate accounting professionals capable of responding to sustainability and AI-driven challenges.Kristina Rudžionienė, Aušrinė Tamulevičiūtė, and Aurelija Kustienė’s study, The relationship between CSR and earnings management in Lithuanian listed companies, explores how sustainability efforts relate to financial behaviour in a small, transitional economy. Contrary to prior expectations, their results indicate a positive link between corporate social responsibility and both accrual- and real-activity earnings management. This surprising outcome suggests that, in some cases, CSR initiatives might be strategically used to hide opportunistic actions. The study offers new empirical insights into ethical authenticity and transparency in financial reporting across Central and Eastern Europe.The intersection of family business and accounting research is explored in Amin Soheili’s paper Family business and accounting research: A structured literature review. Through a systematic review of seventy peer-reviewed papers published between 2000 and 2024, the author maps the theoretical and methodological development of accounting research within family business contexts. Using a SWOT framework, the study highlights the underrepresentation of socioemotional and qualitative dimensions. The review advocates a broader investigation into private and emerging-market family firms, emphasising the need for interdisciplinary approaches that account for the behavioural and relational dynamics of family-owned enterprises.Gintarė Špogienė, Daiva Tamulevičienė, and Kristina Rudžionienė analyse five leading Lithuanian retail chains in their paper Integrating corporate social responsibility into internal decision-making in leading retail chains in Lithuania: A responsibility accounting perspectiveThey highlight a gap between publicly disclosed CSR and the information that genuinely influences managerial decisions. To reduce “informational noise” and enhance accountability, they suggest adapting responsibility accounting and reporting (RAR) to incorporate stakeholder-impact assessment and to categorise decisions as financial, philanthropic, or socially responsible, aligning internal controls with public CSR commitments and fostering more transparent, ethics-based governance.Finally, considering preparedness for the EU’s sustainability regime, Aleksandra Sulik-Górecka, Marzena Strojek-Filus, and Daniel Iskra, in their article Assessment of Polish companies’ preparedness for ESG reporting in the context of its determinants as evaluated by report preparers, explore Polish companies’ readiness through a nationwide survey and non-parametric inference. Most respondents rated themselves as only moderately prepared, with preparedness significantly linked to firm size (but not industry), about 70% viewing ESG reporting as complex, and they highlight a need for investment in personnel and reporting technologies. The study places these findings in the context of the roll-out of CSRD/ESRS and presents them as a baseline for more in-depth quality analysis.Taken together, the articles in this Special Issue reflect the complexity of modern accounting as a discipline that is simultaneously technological, behavioural, regulatory, and ethical. The contributions show how accounting continues to broaden beyond its traditional financial scope, including data analytics, artificial intelligence, linguistic transparency, and sustainability assurance. Each paper not only advances academic discussion but also provides valuable insights for practitioners, educators, and policymakers, enhancing the quality, relevance, and integrity of accounting information.The Editorial Team extends its gratitude to all authors and reviewers for their valuable contributions and diligent work in preparing this issue. We also thank our readers for their continued interest and engagement with the journal. We hope that the studies presented here will inspire further discussion, research, and innovation in the ever-evolving field of accounting.Marzena Remlein* Ana Rep Romić**The Editorial Team of ZTR is pleased to announce that in ZTR’s 49th year of publication, its four quarterly issues contained 39 articles: 25 in English and 14 in Polish. Their authors come from eleven countries (Bulgaria, Estonia, Croatia, Montenegro, Lithuania, Poland, the Czech Republic, Slovakia, Slovenia, Sweden, and Ukraine). We thank all the authors for their cooperation with the Editorial Team and the reviewers of their articles. The manuscripts submitted to ZTR were reviewed in 2025 by 73 reviewers, including 52 from Poland and 21 from abroad. The Editorial Team would like to thank all specialists who provided anonymous reviews and insightful feedback. The list of Polish and foreign reviewers is included in this issue of ZTR and on our journal’s website at https://ztr.skwp.pl/ cms/reviewers. We encourage authors and readers to visit ZTR’s website at https://ztr.skwp.pl/, which contains extensive information about ZTR, including its presence in databases (including Scopus, Web of Science, BazEkon, EBSCO Business Source Ulti-mate, Erich Plus, CEEOL, Cejsh, CROSSREF, DOAJ, and ICI Journals Master List), as well as an invitation to a thematic issue of ZTR in 2026 titled Accounting’s Expanded Horizon: Redefining Internal Practices for Organizational Flourishing (for more, see Call for papers published in ZTR, Vol. 49, No. 2 and at https://ztr.skwp.pl/cms/CMS:647). On behalf of the entire ZTR Editorial Team, I wish all authors, reviewers, members of the Editorial Board, and readers of ZTR a lot of health, happi-ness, and peace, as well as numerous professional successes in 2026. Yours sincerely,Anna Szychta

Dominik Kwietniak, Piotr Oprocha, Jakub Tomaszewski

For every $0<α\le\infty$ we construct a continuous pure mixing map (topologically mixing, but not exact) on the Gehman dendrite with topological entropy $α$. It has been previously shown by Špitalský that there are exact maps on the Gehman dendrite with arbitrarily low positive topological entropy. Together, these results show that the entropy of maps on the Gehman dendrite does not exhibit the paradoxical behaviour reported for graph maps, where the infimum of the topological entropy of exact maps is strictly smaller than the infimum of the entropy of pure mixing maps. The latter result, stated in terms of popular notions of chaos, says that for maps on graphs, lower entropy implies stronger Devaney chaos. The conclusion of this paper says that lower entropy does not force stronger chaos for maps of the Gehman dendrite.

Sergio García-Heredia, Ángela Fernández, Carlos M. Alaíz

One of the fundamental problems within the field of machine learning is dimensionality reduction. Dimensionality reduction methods make it possible to combat the so-called curse of dimensionality, visualize high-dimensional data and, in general, improve the efficiency of storing and processing large data sets. One of the best-known nonlinear dimensionality reduction methods is Diffusion Maps. However, despite their virtues, both Diffusion Maps and many other manifold learning methods based on the spectral decomposition of kernel matrices have drawbacks such as the inability to apply them to data outside the initial set, their computational complexity, and high memory costs for large data sets. In this work, we propose to alleviate these problems by resorting to deep learning. Specifically, a new formulation of Diffusion Maps embedding is offered as a solution to a certain unconstrained minimization problem and, based on it, a cost function to train a neural network which computes Diffusion Maps embedding -- both inside and outside the training sample -- without the need to perform any spectral decomposition. The capabilities of this approach are compared on different data sets, both real and synthetic, with those of Diffusion Maps and the Nystrom method.

Beat Nairz

We define analytic maps between super Riemann surfaces which extend the notion of branched covering maps to a supersymmetric setting. We show that these super covering maps appear naturally both in symmetric product orbifolds of superconformal field theories, as well as in the hybrid formalism for tensionless string theory on $\text{AdS}_3\times S^3\times\mathbb{T}^4$. In the former, they can be used to calculate correlators in a manifestly supersymmetric way, while in the latter they solve Ward identities of correlators with spacetime supersymmetry.

David Glickenstein, Lee Sidbury

Discrete conformal mappings based on circle packing, vertex scaling, and related structures has had significant activity since Thurston proposed circle packing as a way to approximate conformal maps in the 1980s. The first convergence result of Rodin-Sullivan (1987) proved that circle packing maps do indeed converge to conformal maps to the disk. Recent results have shown convergence of maps of other discrete conformal structures to conformal maps as well. We give a general theorem of convergence of discrete conformal mappings between surfaces that allows for a variety of discrete conformal structures and manifolds with or without boundary. The mappings are a composition of piecewise linear discrete conformal mappings and Riemannian barycentric coordinates, called barycentric discrete conformal maps. Estimates of the barycentric discrete conformal maps allow extraction of convergent subsequences and estimates for the pullback of the Riemannian metric, proving conformality. The theorem requires assumptions on fullness of simplices to prevent degenerate triangles and a local discrete conformal rigidity generalizing hexagonal rigidity of circle packings.

A. M. Gribkov, N. D. Chichirova, K. M. Mirsalikhov

In a number of cases, for example, when choosing the design of the exit part of a chimney, when taking into account the characteristics of the underlying surface and meteorological characteristics of the area, or as a means of verifying variant calculations in the ANSYS environment, a study of the trajectory of the smoke plume in natural conditions is required. One of the simplest, most convenient and cheapest ways to determine a trajectory is to photograph it and then decipher it. So, for example, a vertical chimney, if the direction of the camera is raised above the horizon, and the chimney is not located in the center of the photo, it looks inclined in the photo. This means that at the top of the image and at the bottom there are different horizontal linear scales of the image. The angle at which the camera was installed can also be calculated from the photograph. In addition, the same vertical height interval occupies a smaller length in the upper part of the pipe and a larger one in the lower part. This means that in the upper part of the image and in the lower part there are different vertical linear scales of the image. It is also necessary to take into account the fact that objects of the same size have different sizes in the picture. The further away an object is located, the less space it takes up in the photo. Thus, in order to calculate the trajectory of a smoke plume from a photograph, we need to know the orientation of the main optical axis during the photograph and the distance to the photograph plane, which we choose perpendicular to the main optical axis and passing through the object, from which we can determine the initial average linear scales, and the direction smoke plume spread.TARGET. Development of a new, simpler method for recalculating the trajectory of a smoke plume from a chimney using available Google maps to calculate the original scales in a photograph.METHODOLOGY Allows you to trace the entire sequence of actions from determining the coordinates of the shooting point to recalculating the coordinates of the selected points of the torch boundaries in the photograph relative to the emission source onto an orthogonal plane.RESULTS. A new method for calculating the trajectory of a smoke plume from a single photograph has been developed, the accuracy of which was tested using known sizes in the original objects, and which turned out to be higher than that previously used for these purposes.

Xi Chen, Hongming Wang, Xi Tan et al.

Abstract Pilots are considered the final line of defense for aviation safety. Before becoming a pilot, an ab initio pilot must undergo systematic flight training. This study included 25 male flying cadets. Kendall’s coefficient of concordance was used to measure the regional homogeneity of the time series of a given voxel with its 26 nearest neighboring voxels. This operation was performed for all voxels to generate a regional homogeneity map for each participant based on Kendall’s coefficient of concordance. A partial correlation analysis was performed to examine the relationship between regional homogeneity maps and flight training hours. We found that the anterior cingulate cortex in the ab initio group was significantly positively correlated with flight hours. These results suggest a potential relationship between flight training experience and the functional properties of the anterior cingulate cortex.

Krzysztof J. Ciosmak

Let $X$ be a subset of a Hilbert space. We prove that if $v\colon X\to \mathbb{R}^m$ is such that \begin{equation*} \Big\lVert v(x)-\sum_{i=1}^m t_iv(x_i)\Big\rVert\leq \Big\lVert x-\sum_{i=1}^m t_ix_i\Big\rVert \end{equation*} for all $x,x_1,\dotsc,x_m\in\mathbb{R}^m$ and all non-negative $t_1,\dotsc,t_m$ that add up to one, then for any $1$-Lipschitz $u\colon A\to\mathbb{R}^m$, with $A\subset X$, there exists a $1$-Lipschitz extension $\tilde{u}\colon X\to\mathbb{R}^m$ of $u$ such that the uniform distance on $X$ between $\tilde{u}$ and $v$ is the same as the uniform distance on $A$ between $u$ and $v$. Moreover, if either $m\in \{1,2,3\}$ or $X$ is convex, we prove the converse: we show that a map $v\colon X\to\mathbb{R}^m$ that allows for a $1$-Lipschitz, uniform distance preserving extension of any $1$-Lipschitz map on a subset of $X$ also satisfies the above set of inequalities. We also prove a similar continuity result concerning extensions of monotone maps. Our results hold true also for maps taking values in infinite-dimensional spaces.

Lina Yi, Guifeng Zhang, Bowen Zhang

A water quality parameter retrieval scheme based on the UAV push-broom hyperspectral images was designed and validated for assessing the ecological health of Zhang Wei Xin River in Dezhou distinct, China. First, a UAV carrying a push-broom hyperspectral imager that is lightweight and has a small size was used to acquire high spatial and hyperspectral resolution images. Then, the mosaicked reflectance data of the whole river were produced by a seamless image mosaicking method with high geometrical accuracy and spectral fidelity. Next, the in-field measurements of different parameters and the corresponding spectral reflectance from the mosaicked images at the sampling points were used to build the water quality parameter retrieval models for total phosphorus (TP), chlorophyll a (Chla), and total suspended solids (TSS). To validate the model, the retrieval results of the testing sampling points were compared with the measured parameters. The coefficients of determination R² of TP, Chla, and TSS were 0.886, 0.918, and 0.968, respectively. The retrieved TP, Chla, and TSS maps showed that the water pollution of Zhang Wei Xin River is serious, the total phosphorus exceeds the standard, and the water body is in a state of eutrophication. The UAV-based hyperspectral remote sensing technique provides a cost-effective method for inland water monitoring at a local scale with high accuracy.

Marina Filipović, Tihomir Frangen, Josip Terzić et al.

ABSTRACTOur study focuses on a sizeable transboundary karst catchment in Croatia and Bosnia and Herzegovina, extending over 2000 km2. A complex underground conduit system and extreme karst forms heterogeneity are the main characteristics of the area in question. Since determining the boundary of such a large and complex catchment is difficult, we used different kinds of data sets, of which the most relevant are the available geological data, hydrochemical data, hydrological data, and tracing tests data, to divide the regional catchment into six subcatchments. We also examined past archived reports and carried out new hydrological investigations of several major and minor springs. Our research results in a hydrogeological map that can be used as a base for establishing site-specific groundwater protection zones, for water balance calculations and the planning of new research in this area, especially the ones regulating combined cross-border efforts to prevent groundwater contamination and ensure sufficient drinking water.

William A. Catterall

ABSTRACTVoltage-gated sodium channels initiate action potentials in nerve and muscle, and voltage-gated calcium channels couple depolarization of the plasma membrane to intracellular events such as secretion, contraction, synaptic transmission, and gene expression. In this Review and Perspective article, I summarize early work that led to identification, purification, functional reconstitution, and determination of the amino acid sequence of the protein subunits of sodium and calcium channels and showed that their pore-forming subunits are closely related. Decades of study by antibody mapping, site-directed mutagenesis, and electrophysiological recording led to detailed two-dimensional structure-function maps of the amino acid residues involved in voltage-dependent activation and inactivation, ion permeation and selectivity, and pharmacological modulation. Most recently, high-resolution three-dimensional structure determination by X-ray crystallography and cryogenic electron microscopy has revealed the structural basis for sodium and calcium channel function and pharmacological modulation at the atomic level. These studies now define the chemical basis for electrical signaling and provide templates for future development of new therapeutic agents for a range of neurological and cardiovascular diseases.

M. Kakooei, Y. Baleghi

Shadow detection provides worthwhile information for remote sensing applications, e.g. building height estimation. Shadow areas are formed in the opposite side of the sunlight radiation to tall objects, and thus, solar illumination angle is required to find probable shadow areas. In recent years, Very High Resolution (VHR) imagery provides more detailed data from objects including shadow areas. In this regard, the motivation of this paper is to propose a reliable feature, Shadow Low Gradient Direction (SLGD), to automatically determine shadow and solar illumination direction in VHR data. The proposed feature is based on inherent spatial feature of fine-resolution shadow areas. Therefore, it can facilitate shadow-based operations, especially when the solar illumination information is not available in remote sensing metadata. Shadow intensity is supposed to be dependent on two factors, including the surface material and sunlight illumination, which is analyzed by directional gradient values in low gradient magnitude areas. This feature considers the sunlight illumination and ignores the material differences. The method is fully implemented on the Google Earth Engine cloud computing platform, and is evaluated on VHR data with 0.3m resolution. Finally, SLGD performance is evaluated in determining shadow direction and compared in refining shadow maps.

Sucharitha Shetty, B. Dinesh Rao, Srikanth Prabhu

The increasing demand for the simultaneous transaction and review of the data for either decision making or forecasting has created a need for faster and better Hybrid Transactional/Analytical Processing (HTAP). This paper emphasizes the speedup of Online Analytical Processing (OLAP) operations in an HTAP environment where analytical queries are mainly repetitive and contain non-indexed keys as their predicates. Zone maps and materialized views are popular approaches adopted by more extensive databases to address this issue. However, they are absent in in-memory databases because of space constraints. Instead, in-memory databases load the cache with result pages of frequently accessed queries. Increasing the number of such queries can fill the cache and raise the system&#x2019;s overhead. This paper presents Query&#x005F;Dictionary, a hybrid storage solution that leverages the full capabilities of SQLite by retaining less information of repetitive queries in the cache and efficiently accommodating the newly updated data by the end-user. The solution proposes storing page-level metadata query information for a larger result set and row-level information for a smaller result set. It demonstrates Query&#x005F;Dictionary capabilities on three types of representative queries: single table, binary join, and transactional queries on non-indexed attributes. In comparison with SQLite, the proposed method performs better.

Boris Eberhardt, Benedikt A. Poser, N. Jon Shah et al.

Spoke trajectory parallel transmit (pTX) excitation in ultra-high field MRI enables B1+ inhomogeneities arising from the shortened RF wavelength in biological tissue to be mitigated. To this end, current RF excitation pulse design algorithms either employ the acquisition of field maps with subsequent non-linear optimization or a universal approach applying robust pre-computed pulses. We suggest and evaluate an intermediate method that uses a subset of acquired field maps combined with generative machine learning models to reduce the pulse calibration time while offering more tailored excitation than robust pulses (RP).The possibility of employing image-to-image translation and semantic image synthesis machine learning models based on generative adversarial networks (GANs) to deduce the missing field maps is examined. Additionally, an RF pulse design that employs a predictive machine learning model to find solutions for the non-linear (two-spokes) pulse design problem is investigated.As a proof of concept, we present simulation results obtained with the suggested machine learning approaches that were trained on a limited data-set, acquired in vivo. The achieved excitation homogeneity based on a subset of half of the B1+ maps acquired in the calibration scans and half of the B1+ maps synthesized with GANs is comparable with state of the art pulse design methods when using the full set of calibration data while halving the total calibration time. By employing RP dictionaries or machine-learning RF pulse predictions, the total calibration time can be reduced significantly as these methods take only seconds or milliseconds per slice, respectively.

Francisco J Navarro-Meneses

The creation of value is a critical factor that determines the competitive capacity of firms and their ability to survive. Notwithstanding its importance, value creation usually becomes a fuzzy concept that is difficult to grasp, especially when increasingly complex elements of reality are incorporated into its analysis. Building on the narrative of the firm as a complex adaptive system, this article provides empirical evidence showing value creation as emergent behavior resulting from hyper-connected value repositories. Several implications for scholars and practitioners are discussed. For scholars, expert knowledge is provided from 28 airline industry executives around the world together with a method based on fuzzy cognitive maps that allows modeling and simulating value creation in airlines through 26 value repositories and 77 interdependencies. For practitioners, the article raises awareness of the need to incorporate a complexity mindset into value creation analysis and smooths the transition towards a value performance management tool.