Information Theory Research Articles

Radiation Detectors and Sensors in Medical Imaging.

Medical imaging instrumentation design and construction is based on radiation sources and radiation detectors/sensors. This review focuses on the detectors and sensors of medical imaging systems. These systems are subdivided into various categories depending on their structure, the type of radiation they capture, how the radiation is measured, how the images are formed, and the medical goals they serve. Related to medical goals, detectors fall into two major areas: (i) anatomical imaging, which mainly concerns the techniques of diagnostic radiology, and (ii) functional-molecular imaging, which mainly concerns nuclear medicine. An important parameter in the evaluation of the detectors is the combination of the quality of the diagnostic result they offer and the burden of the patient with radiation dose. The latter has to be minimized; thus, the input signal (radiation photon flux) must be kept at low levels. For this reason, the detective quantum efficiency (DQE), expressing signal-to-noise ratio transfer through an imaging system, is of primary importance. In diagnostic radiology, image quality is better than in nuclear medicine; however, in most cases, the dose is higher. On the other hand, nuclear medicine focuses on the detection of functional findings and not on the accurate spatial determination of anatomical data. Detectors are integrated into projection or tomographic imaging systems and are based on the use of scintillators with optical sensors, photoconductors, or semiconductors. Analysis and modeling of such systems can be performed employing theoretical models developed in the framework of cascaded linear systems analysis (LCSA), as well as within the signal detection theory (SDT) and information theory.

Morphogenesis analysis of icosahedral and prismatic tensegrity modules

Morphogenesis is a critical aspect of tensegrity system design. This paper explores icosahedral and prismatic tensegrity modules' pattern formation and foundational theories. First, a material consumption functional and self-strain energy functional are introduced from an engineering perspective, along with a variational principle involving independent dual-variable in the morphogenesis process of tensegrity structures. Next, a Symbol Parsing Method is proposed and successfully applied to the optimal morphology analysis of the icosahedral tensegrity module. Due to memory limitations in personal computers, the Singular Value Decomposition of the symbolic equilibrium matrix for the prismatic tensegrity module is constrained. As an alternative, a discrete numerical solution, the semi-symbolic parsing method, is obtained by directly utilizing a numerical equilibrium matrix. This method was recently employed to analyze and optimize a practical tensegrity footbridge designed by the authors. Lastly, the paper delves into the stability of self-equilibrium states in icosahedral and classical prismatic tensegrity modules by employing a second-order variational analysis of the self-strain energy functional. The findings presented are expected to contribute to future research on the morphogenesis of tensegrity structures.

A Novel Hypersonic Target Trajectory Estimation Method Based on Long Short-Term Memory and a Multi-Head Attention Mechanism.

To address the complex maneuvering characteristics of hypersonic targets in adjacent space, this paper proposes an LSTM trajectory estimation method combined with the attention mechanism and optimizes the model from the information-theoretic perspective. The method captures the target dynamics by using the temporal processing capability of LSTM, and at the same time improves the efficiency of information utilization through the attention mechanism to achieve accurate prediction. First, a target dynamics model is constructed to clarify the motion behavior parameters. Subsequently, an LSTM model incorporating the attention mechanism is designed, which enables the model to automatically focus on key information fragments in the historical trajectory. In model training, information redundancy is reduced, and information validity is improved through feature selection and data preprocessing. Eventually, the model achieves accurate prediction of hypersonic target trajectories with limited computational resources. The experimental results show that the method performs well in complex dynamic environments with improved prediction accuracy and robustness, reflecting the potential of information theory principles in optimizing the trajectory prediction model.

Generalized Quantum Measurement in Spin-Correlated Hyperon-Antihyperon Decays

Abstract The rapid developments of quantum information science (QIS) have opened up new avenues for exploring fundamental physics. Quantum nonlocality, a key aspect for distinguishing quantum information from classical one, has undergone extensive examinations in particles’ decays through the violation of Bell-type inequalities. Despite these advancements, a comprehensive framework based on quantum information theory for particle interaction is still lacking. Trying to close this gap, we introduce a generalized quantum measurement description for decay processes of spin-1/2 hyperons. We validate this approach by aligning it with established theoretical calculations and apply it to the joint decay of Λ Λ ¯ pairs. We employ quantum simulation to observe the violation of Clauser–Horne–Shimony–Holt inequalities in η c / χ c 0 → Λ Λ ¯ processes. Our generalized measurement description is adaptable and can be extended to a variety of high energy processes, including decays of vector mesons, J / ψ , ψ ( 2 S ) → Λ Λ ¯ , in the Beijing Spectrometer III (BESIII) experiment at the Beijing Electron Positron Collider (BEPC). The methodology developed in this study can be applied to quantum correlation and information processing in fundamental interactions.

The Evanescence of Ritual and Its Consequences: Reflections on the Phenomenology of Human Communication in the Rise of Cybernetic Culture

This paper addresses semiotic elements of ritual in human encounter. The notion of an essential ritual presence in the existential/communicative connection of persons has been established in the work of Langer, Gadamer, and Jakobson. Yet, as Richard Lanigan maintains, vital aspects of Jakobson’s model of communication are typically missed in the application of his work, a consequence of which is that social science no longer differentiates between “communication” and “information”. As such, everything perceived as meaningful is reducible to “message”, and thus, effective communication means merely “finding the right message”. The regression to our current cybernetic world, along with the intellectual paradigms enabling it, was never a foregone conclusion, but the entrenchment of social science in information theory makes it clear that an epistemological commitment to a semiotic phenomenology of communicative existence—and the visibility of ritual life—may well be our only way out.

Putting Appadurai's “Capacity to Aspire” and Sen's Capability Approach into Dialogue

ABSTRACT In his seminal paper, Appadurai (2004) introduced the concept of “capacity to aspire” as a cultural capacity that may open routes out of poverty for the poor. He envisions entering a robust dialogue between his conception and the capability approach. The notion of aspirations is attractive for capability scholars since it seems to answer some shortcomings of the capability approach, namely the lack of any theory of preference or value formation, the missing dynamics, the question of countering adaptive preferences and eliciting information on people’s values. I analyse capability literature on aspirations and argue that although they relate to these shortcomings, they fail to eliminate them and to enter the dialogue Appadurai invited. For doing this, the collective nature of the capacity to aspire has to be recognised. I suggest that the capacity to aspire rather than remedying one of the above-mentioned shortcomings is best understood as an example of Sen’s concept of agency and how poor people can build up, exercise and sustain agency.

A robust decision-making approach for designing coastal groundwater quality monitoring networks.

This paper presents a new approach to the spatiotemporal design of groundwater quality monitoring networks for coastal aquifers. A fusion model combines the outputs of several developed simulation models to make estimates more accurate. A modified GALDIT method is used to incorporate the aquifer vulnerability to saltwater intrusion. The value of information (VOI) theory is applied to determine sufficient monitoring wells. The groundwater quality monitoring network is designed by employing a robust decision-making (RDM) approach under different management strategies and economic considerations. This approach incorporates the deep uncertainties of some critical variables, including water level and total dissolved solids (TDS) concentration at the coastline and pumping flow rates of agricultural wells. The new methodology is implemented in the coastal Qom-Kahak aquifer, Iran. The results illustrate that the combination model has significantly improved evaluation criteria compared to individual prediction models. The fusion model results indicate that thirty monitoring wells would be ideal. The RDM-based analyses in the Qom-Kahak aquifer showed that an optimal network with 30 monitoring wells outperforms the current network regarding various criteria, such as VOI and variance of estimation error. The new well configuration also demonstrates a suitable spatial distribution. Given that the current sampling frequencies are unsuitable for areas with varying vulnerabilities, we recommend sampling every 3months in areas with moderate vulnerabilities and once every three seasons in areas with low vulnerabilities, based on the information transfer index. Finally, a management strategy in which the pumping rate should be less than 60% of the current rate is suggested to prevent saltwater intrusion into the aquifer.

Assembly Theory is an approximation to algorithmic complexity based on LZ compression that does not explain selection or evolution

We formally prove the equivalence between Assembly Theory (AT) and Shannon Entropy via a method based upon the principles of statistical compression that belongs to the LZ family of popular compression algorithms. Such popular lossless compression algorithms behind file formats such as ZIP and PNG have been shown to empirically reproduce the results that AT considers its cornerstone. The same results have also been reported before AT in successful application of other complexity measures in the areas covered by AT such as separating organic from non-organic molecules and in the context of the study of selection and evolution. We demonstrate that the assembly index is equivalent to the size of a minimal context-free grammar. The statistical compressibility of such a method is bounded by Shannon Entropy and other equivalent traditional LZ compression schemes, such as LZ77 and LZW. We also demonstrate that AT, and the algorithms supporting its pathway complexity, assembly index, and assembly number, define compression schemes and methods that are subsumed into algorithmic information theory. We conclude that the assembly index and the assembly number do not lead to an explanation or quantification of biases in generative (physical or biological) processes, including those brought about by (abiotic or biotic) selection and evolution, that could not have been arrived at using Shannon Entropy, or that have not been already reported before using classical information theory or algorithmic complexity.

A brief tutorial on information theory

At the 2023 Les Houches Summer School on Theoretical Biological Physics, several students asked for some background on information theory, and so we added a tutorial to the scheduled lectures. This is largely a transcript of that tutorial, lightly edited. It covers basic definitions and context rather than detailed calculations. We hope to have maintained the informality of the presentation, including exchanges with the students, while still being useful.

Novel single-phase Li2SiO3 microwave dielectric ceramic with low permittivity

Novel low-permittivity lithium metasilicate (Li2SiO3) ceramics were synthesized to explore the relationships between crystal structure parameters and dielectric properties. X-ray diffraction and Rietveld refinement indicated that the Li2SiO3 ceramics formed a single orthorhombic structure with a Cmc21 space group. Optimal microwave dielectric properties of εr = 6.20 ± 0.02, Q×f = 30,550 ± 250 GHz (f0 = 15.5 GHz), and τf = −40.95 ± 0.56 ppm/℃ were achieved through sintering at 1025 ℃. Raman spectroscopy analysis showed that the values of εr and Q×f were negatively correlated with the Raman shift and full width at half maximum of the strongest peak at 982 cm−1, respectively. Meanwhile, the Phillips–Vechten–Levine theory revealed that the εr values and the Q×f values were closely related to the average bond ionicity and the lattice energy of the Si-O bonds, respectively. Moreover, the increase in τf values depended on the increase in oxygen bond valence and the distortion of the [LiO4] tetrahedron. These results on the Li2SiO3 ceramics could provide some theoretical information for developing high-performance microwave dielectric ceramics.

Environmental habitus of chefs and food waste management in hospitality operations

Although many chefs have developed the habit to practice food waste management in the kitchen, so-called environmental habitus, little is known about how this habitual practice has formed and how/if it has evolved with time. This study combines practice theory and theory of habit formation to explore the (f)actors that have influenced the formation and evolvement of environmental habitus among chefs. Interpretive phenomenological analysis is used to examine the lived experiences of 18 senior chefs in Indonesia who have habitually engaged in food waste management. The study establishes the critical role of mothers in shaping personal outlook of chefs on the importance of food waste reduction. Senior chefs are key for reinforcing this outlook, but also for providing necessary competencies and tools for resourceful cooking. The study highlights family upbringing and on-the-job training as the critical (f)actors in the formation and evolvement of the habitual practice of food waste management among future chefs.

Recognizing Statistical Problems in Reports of Clinical Trials: A Readers' Aid. Part 33 of a Series on Evaluation of Scientific Publications.

Readers of clinical trial reports should be able to critically evaluate the design, results, and conclusions of the trial. There are internationally accepted guidelines that define methodological standards for trial planning, statistical methods, and the display and interpretation of the results. Publications may nonetheless contain erroneous findings and interpretations. Statistical errors can arise in the planning of the trial, the analysis and display of the results, as well as in the interpretation of p-values and treatment effects in experimental and observational clinical trials. A useful aid for readers of medical publications should include a description of the potential statistical problems without complex theoretical background information. With this aim, we discuss certain major types of statistical error that the reader should be familiar with in order to be able to interpret the conclusions of these publications more easily. Statistical errors can already arise at an early stage through the choice of the wrong question to be addressed or the wrong population to be analyzed; such errors will inevitably have consequences. Before the start of any clinical trial, a primary endpoint must be defined, the sample size must be calculated, and the trial must be appropriately registered (among other requirements). With regard to the analysis, readers should for example take into account whether a statistical analysis plan with an intention-to-treat analysis existed for the study in question. They must be able to recognize erroneous methods of displaying and comparing data, confounding, as well as incorrect interpretations of p-values, and should take these problems into account when interpreting the findings. The problem of invalid causal inferences is not restricted to observational studies. Statistical errors do, indeed, arise. They should be detected as early as possible in various test instances. Nonetheless, readers should be able to judge independently whether the published clinical trial reflects meticulous and correct trial planning, appropriate display of the trial's results, and a proper, reasoned interpretation of the findings. The published checklists are a good aid for this purpose.

An Asteroid Impact Event Forming the Intercontinental Geomorphology from East Asia to North Africa, and More

From the perspective of the thin shell droplet dynamics and based on the geographical and morphological data of the vast area from east to west Asia, this study suggests a tangential impact event of a quartzite asteroid with 430km diameter which may explain the formation of all basins, plateaus, mountains, Gobi and deserts northeast from the Outer Mongolia East Gobi Province and southwest to the Sahara Desert and connect the series of the huge geomorphic formation event with a homologous and sequential formation process. On this basis, a "continent formation theory" is proposed that continent and mountain are formed from the cooling of lava surge flow, and the new continental movement and structure was thus explained as well.

Proposition of Optimization of the Meetinthemiddle Protocol for Quantum Repeaters

Quantum computing relies on concepts derived from classical information theory and quantum physics. In order for quantum communications to be a reality, it is essential to have the most advanced infrastructures in place. In this paper, we explore the significance of quantum communication and the utilization of quantum repeaters, which rely on the phenomenon of quantum entanglement. We present the MeetInTheMiddle protocol for quantum repeaters and its total transmission probability, and then propose an improvement of this protocol based on the comparison of the total transmission probability.

Metrics and geodesics on fuzzy spaces

Abstract We study the fuzzy spaces (as special examples of noncommutative manifolds) with their quasicoherent states in order to find their pertinent metrics. We show that they are naturally endowed with two natural “quantum metrics” which are associated with quantum fluctuations of “paths”. The first one provides the length the mean path whereas the second one provides the average length of the fluctuated paths. Onto the classical manifold associated with the quasicoherent state (manifold of the mean values of the coordinate observables in the state minimising their quantum uncertainties) these two metrics provides two minimising geodesic equations. Moreover, fuzzy spaces being not torsion free, we have also two different autoparallel geodesic equations associated with two different adiabatic regimes in the move of a probe onto the fuzzy space. We apply these mathematical results to quantum gravity in BFSS matrix models, and to the quantum information theory of a controlled qubit submitted to noises of a large quantum environment.

Developing and evaluating a risk-informed decision support system for earthquake early warning at a railway bridge

Earthquake early warning (EEW) systems provide timely information on the arrival of strong seismic waves at a site. Such information can help mitigate the consequences of earthquakes on the operation of infrastructure assets. EEW-informed mitigation actions should stem from risk-based decision-making protocols, and EEW benefits should be evaluated for the range of possible rupture scenarios that affect an asset of interest. This paper addresses these challenges specifically for railway bridges by: (1) developing a risk-informed EEW decision support system (DSS) for these assets; and (2) quantifying the effectiveness of the proposed EEW-DSS in mitigating seismic risks for railway bridges across relevant rupture scenarios. The proposed EEW-DSS combines information on site-specific seismic hazard, time-dependent EEW algorithm outputs, probabilistic seismic demand modeling, damage/derailment fragilities, and seismic loss models. These modeling components compose a multi-criteria decision-making framework. Value of information theory is then proposed to estimate the loss-mitigation benefits of the EEW-DSS, accounting for varied stakeholder risk priorities as well as dynamic lead-time/accuracy tradeoffs related to EEW performance. A railway bridge with multiple piers is adopted for the case study, which demonstrates the importance of risk-based, uncertainty-informed decision-making to the overall effectiveness of EEW in potentially reducing seismic losses.

Extracting Tuscan phonetic correspondences from dialect pronunciations automatically

Abstract We present a novel approach to identifying individual pairs of phonetic correspondences in a dataset of dialect pronunciations. This continues work identifying shibboleths (i.e., characteristic features of a given dialect), a category that has interested dialectology and that dialectometrical research has examined mostly in the form of categorical data or entire phonetic transcriptions. This article reaches into segmental sequences (phonetic transcriptions) to identify individual phonetic correspondences. We follow earlier work in examining how distinctive and how representative a given phonetic correspondence is for a selected group of varieties. We proceed from string alignments, and innovate in characterizing the important notions via information theory. Despite minor problems, the method improves on the generality of competing approaches and can be shown to be useful in detecting characteristic phonetic correspondences in Tuscan varieties. We argue that this facilitates deeper investigation into the relation between aggregating approaches to dialectology and approaches proceeding from features.

Low surface brightness dwarf galaxies and their globular cluster populations around the low-density environment of our closest S0 NGC 3115

Abstract Understanding faint dwarf galaxies is fundamental to the development of a robust theory of galaxy formation on small scales. Since the discovery of a population of ultra diffuse galaxies (UDGs) rich in globular clusters (GCs) in Coma, an increasing number of studies on low surface brightness dwarf galaxies (LSBds) have been published in recent years. The most massive LSBds have been observed predominantly in groups and clusters, with properties displaying dependence on the environment. In this work, we use deep DECam imaging to systematically identify LSBds and their GC populations around the low-density environment of NGC 3115. We carefully analyse the structure and morphology of 24 candidates, 18 of which are reported for the first time. Most candidates exhibit red colours suggesting a connection between their colour and distance to NGC 3115. We followed up with Gemini GMOS imaging 9 LSBds to properly identify their GC populations. We derive lower limits for the number of GCs associated with each galaxy. Our analysis reveals that they occur around of the same loci of Fornax LSB dwarf GC systems. The relationship between the number of GCs and total mass provides a tool in which, by counting the GCs in these galaxies, we estimate an upper limit for the total mass of these LSB dwarfs, obtaining the mean value of ∼3.3 × 1010 M⊙. Our results align with expectations for dwarf-sized galaxies, particularly regarding the distribution and specific frequency of their GC systems.

Design and Technological Aspects of Integrating Multi-Blade Machining and Surface Hardening on a Single Machine Base

Modern mechanical engineering faces high competition in global markets, which requires manufacturers of process equipment to significantly reduce production costs while ensuring high product quality and maximum productivity. Metalworking occupies a significant part of industrial production and consumes a significant share of the world’s energy and natural resources. Improving the technology of manufacturing parts with an emphasis on more efficient use of metalworking machines is necessary to maintain the competitiveness of the domestic machine tool industry. Hybrid metalworking systems based on the principles of multi-purpose integration eliminate the disadvantages of monotechnologies and increase efficiency by reducing time losses and intermediate operations. The purpose of this work is to develop and implement a hybrid machine tool system and an appropriate combined technology for manufacturing machine parts. Theory and methods. Studies of the possible structural composition and layout of hybrid equipment at integration of mechanical and surface-thermal processes were carried out, taking into account the basic provisions of structural synthesis and componentization of metalworking systems. Theoretical studies were carried out using the basic provisions of system analysis, geometric theory of surface formation, design of metalworking machines, methods of finite elements, and mathematical and computer modeling. The mathematical modeling of thermal fields and structural-phase transformations during HEH HFC was carried out in ANSYS (version 19.1) and SYSWELD (version 2010) software packages using numerical methods of solving differential equations of unsteady heat conduction (Fourier equation), carbon diffusion (2nd Fick’s law) and elastic–plastic behavior of the material. The verification of the modeling results was carried out using in situ experiments employing the following: optical and scanning microscopy; and mechanical and X-ray methods of residual stress determination. Formtracer SV-C4500 profilograph profilometer was used in the study for simultaneous measurement of shape deviations and surface roughness. Surface topography was assessed using a Walter UHL VMM 150 V instrumental microscope. The microhardness of the hardened surface layer of the parts was evaluated on a Wolpert Group 402MVD. Results and discussion. The original methodology of structural and kinematic analysis for pre-design studies of hybrid metalworking equipment is presented. Methodological recommendations for the modernization of multi-purpose metal-cutting machine tool are developed, the implementation of which will make it possible to implement high-energy heating with high-frequency currents (HEH HFC) on a standard machine tool system and provide the formation of knowledge-intensive technological equipment with extended functionality. The innovative moment of this work is the development of hybrid metalworking equipment with numerical control and writing a unique postprocessor to it, which allows to realize all functional possibilities of this machine system and the technology of combined processing as a whole. Special tooling and tools providing all the necessary requirements for the process of surface hardening of HEH HFC were designed and manufactured. The conducted complex of works and approbation of the technology of integrated processing in real conditions in comparison with traditional methods of construction of technological process of parts manufacturing allowed to obtain the following results: increase in the productivity of processing by 1.9 times; exclusion of possibility of scrap occurrence at finishing grinding; reduction in auxiliary and preparatory-tasking time; and reduction in inter-operational parts backlogs.

Increase of Complexity from Classical Greek to Latin Poetry

In this paper a method is developed to analyze the increase of complexity from classical Greek poetry to classical Latin poetry by mapping large samples of poems onto a symbolic time series. This mapping setup intends to characterize the regular succession of rhythms, that is, the patterns of stressed and unstressed syllables in a verse. Using techniques from information theory; more precisely, the mutual information function, it is shown how the rhythmical patterns in Greek poetry evolve to more complex behavior in Latin poetry. Some interesting results are reported.