Numerical Search Research Articles

Numerical search for the effective thermal conductivity of cracked media

Spacecraft parts accumulate damage during operation and defects that are invariably present even in new designs may grow. This leads to changes in the behavior of individual parts of the space vehicle and, consequently, to the risk of fracture. A more accurate assessment of spacecraft safety requires internal defects to be included in the material models under consideration. One of the main hazardous effects on space objects is multiple temperature heating and cooling due to periodic action of solar rays. This paper presents a study of thermal conduction of media containing cracks. It is carried out with the help of a technique developed by the authors to determine the effective thermal conductivity of materials and based on approximate numerical solution of the steady-state thermal conduction problem for a three-dimensional medium with cracks by the boundary element method. This technique allows to obtain the distribution of the temperature field and heat flux density at any point of the body under consideration, as well as to calculate the effective parameters of materials with high accuracy at relatively low calculation time using ordinary personal computers of average power. The basis of the numerical method presented in this paper is the decomposition of the desired solution into a series of some pre-calculated analytical solutions of the heat conduction equations. The dependence of the effective thermal conductivity on the density of thermally insulated cracks was considered. The formula of this dependence is proposed. Verification of the proposed methodology was carried out by comparing the numerical results of a number of problems with the results of other authors.

Mathematical Information Retrieval: A Review

Mathematical formulas are commonly used to demonstrate theories and basic fundamentals in the Science, Technology, Engineering, and Mathematics (STEM) domain. The burgeoning research in the STEM domain results in the mass production of scientific documents that contain both textual and mathematical terms. In scientific information, the definition of mathematical formulas is expressed through context and symbolic structure that adheres to strong domain-specific notions. Whereas the retrieval of textual information is well-researched, and numerous text-based search engines are present. However, textual information retrieval systems are inadequate for searching scientific information containing mathematical formulas, including simple symbols to complicated mathematical structures. The retrieval of mathematical information is infancy, and it requires the inclusion of new technologies and tools to promote the retrieval of scientific information and the management of digital libraries. This paper provides a comprehensive study of mathematical information retrieval, highlights their challenges and future opportunities.

An efficient approach for searching three-body periodic orbits passing through Eulerian configuration

A new efficient approach for searching three-body periodic equal-mass collisionless orbits passing through Eulerian configuration is presented. The approach is based on a symmetry property of the solutions at the half period. Depending on two previously established symmetry types on the shape sphere, each solution is presented by one or two distinct initial conditions (one or two points in the search domain). A numerical search based on Newton’s method on a relatively coarse search grid for solutions with relatively small scale-invariant periods T∗<70 is conducted. The linear systems at each Newton’s iteration are computed by high order high precision Taylor series method. The search produced 12,431 initial conditions (i.c.s) corresponding to 6333 distinct solutions. In addition to passing through the Eulerian configuration, 35 of the solutions are also free-fall ones. Although most of the found solutions are new, all linearly stable solutions among them (only 7) are old ones. Particular attention is paid to the details of the high precision computations and the analysis of accuracy. All i.c.s are given with 100 correct digits.

Safeguarding Oscillators and Qudits with Distributed Two-Mode Squeezing

Recent advancements in multi-mode Gottesman-Kitaev-Preskill (GKP) codes have shown great promise in enhancing the protection of both discrete and analog quantum information. This broadened range of protection brings opportunities beyond quantum computing to benefit quantum sensing by safeguarding squeezing — the essential resource in many quantum metrology protocols. However, the potential for quantum sensing to benefit quantum error correction has been less explored. In this work, we provide a unique example where techniques from quantum sensing can be applied to improve multi-mode GKP codes. Inspired by distributed quantum sensing, we propose the distributed two-mode squeezing (dtms) GKP codes that offer benefits in error correction with minimal active encoding operations. Indeed, the proposed codes rely on a single (active) two-mode squeezing element and an array of beamsplitters that effectively distributes continuous-variable correlations to many GKP ancillae, similar to continuous-variable distributed quantum sensing. Despite this simple construction, the code distance achievable with dtms-GKP qubit codes is comparable to previous results obtained through brute-force numerical search \cite{lin2023closest}. Moreover, these codes enable analog noise suppression beyond that of the best-known two-mode codes \cite{noh2020o2o} without requiring an additional squeezer. We also provide a simple two-stage decoder for the proposed codes, which appears near-optimal for the case of two modes and permits analytical evaluation.

Novel ASEP-inspired solutions of the Yang-Baxter equation

Abstract We explore the algebraic structure of a particular ansatz of the Yang-Baxter equation (YBE), which is inspired by the Bethe Ansatz treatment of the asymmetric simple exclusion process spin-model. Various classes of Hamiltonian density arriving from the two types of R-matrices are found, which also appear as solutions of the constant YBE. We identify the idempotent and nilpotent categories of such constant R-matrices and perform a rank-1 numerical search for the lowest dimension. A summary of the final results reveals general non-Hermitian spin-1/2 chain models.

Measuring Heuristic Accuracy on the Performance of Search Algorithms in Solving 8-Puzzle Problems

The goal of this paper is to examine the effect of heuristic accuracy on the performance of search algorithms in solving 8-puzzle problems. The 8-puzzle is a popular benchmark search problem in Artificial Intelligence, and numerous search strategies have been developed to solve it. This research evaluates the performance of search algorithms using different heuristics to determine the optimal level of heuristic accuracy for solving 8-puzzle problems. Several search algorithms, including uniform cost search and A* search, were implemented and tested using different heuristics. Manhattan and Euclidean distances were chosen as heuristics for A* algorithm. Heuristics play a crucial role in guiding these algorithms towards the solution, and their accuracy can greatly impact the performance of the search. Results revealed that reduction attained in both time and space complexity by A* search with Manhattan heuristic is over 99.1% for the average case, while the reduction in the effective branching factor is over 21.1%. These results from the experiments provide insights into the trade-off between heuristic accuracy and search efficiency, and contribute to a better understanding of the behavior of search algorithms in complex problems

Application of an offline grey box method for predicting the manoeuvring performance

The prediction of manoeuvring performance for safe navigation and effective design of ships increasingly depends on artificial intelligence (AI), mainly digital twin technology. This technology requires a digital model of the physical ship. The hydrodynamic coefficients and parameters of these models are commonly obtained through two experimental methods: the planar motion mechanism (PMM) and the circular motion test (CMT). These methods are time-consuming and expensive, which may not be feasible during the early stages of the design process. This study investigates a cost-effective alternative approach to these methods by implementing a grey box method on ships. For the first of these implementations, a full-scale tanker ship was applied with artificial training data of zigzag manoeuvres. A validation study was carried out by comparing the simulation and free-running model test results of the tanker. For the second of these implementations, a scale model of a car carrier was selected, and several numerical search methods were combined to obtain a more accurate digital model. The 3-degree-of-freedom (DOF) Manoeuvring Modelling Group (MMG) models identified through this combination were validated with simulations and compared with the free-running model test results for various manoeuvres. The contribution of this study lies in the accurate capture of the manoeuvring characteristics of the physical model, which is achieved through the use of the adjustment interval and the combination of various numerical search method of the grey box method. Consequently, the developed model can be used in future studies as a faster decision-making tool for determining the straight-line stability or instability of a ship in the ship design and in predicting the manoeuvring performance of the ship.

EXPERIENCE IN THE ORGANISATION OF DESIGN AND CONSTRUCTION WORK IN THE RELIGIOUS ARCHITECTURE OF SLOBOZHANSHCHYNA

In developing the sacred component of modern cities of Ukraine, new problems arise that go beyond the traditional understanding of church architecture as purely parochial and create numerous searches for solutions. Foremost, it concerns the functional expansion and activation of the role of church architecture in modern large-scale urban planning conditions. In the city, where predominantly chaotic interpretation of the urbanised space has returned, there are no other means of overcoming the crisis of new uniformity than turning to the complex development of similar-scale sacred structures. Such an understanding of urban problems requires the development of a new typology of sacred complexes and centres for their solution. No centralised construction organisation existed in Slobidska Ukraina in the 17th or 18th centuries. Professional architectural education in Slobozhanshchyna appeared in 1768 with the creation of additional classes at the Kharkiv Collegium, which produced architects P. A. Yaroslavskyi, S. P. Chernyshov, and others. With the introduction of the Kharkiv Provincial Government on December 12, 1796, Yaroslavskyi became the first Kharkiv provincial architect. He designed and supervised the construction of dozens of churches in the province. Gradually, the provincial authorities took over architectural and construction control and design. The Construction Department that emerged in the province in 1865 became the central institution that monitored the construction and acceptance of projects of places of worship for which the provincial engineer was in charge. The creation of controlling and regulatory institutions and the increased professionalism of architects made it possible to establish the organisation of design and construction work. In 1863, the position of diocesan architect emerged. The first to hold this position was the architect Kraievskyi, followed by F. I. Danylov (1865–1885). Each author had a concept of creativity and a thorough knowledge of architectural typology and theory. High professionalism stemmed from an excellent architectural education and knowledge of the basics of architectural craftsmanship, including expertise in architectural structures and forms drawn from regional Ukrainian traditions. The architect exercised constant control over all churches under construction, which allowed churches to be built precisely according to the project and meet the specified deadlines. The study found that architects had to follow the established rules, or their projects would not receive consideration. The Construction Department of the Kharkiv Provincial Government, responsible for overseeing the construction of churches, headed by the provincial engineer, strictly monitored the documentation of the building. The study reveals aspects of design and construction in the religious architecture of Slobozhanshchyna and presents the methods of design and construction work. The article discusses several architects engaged in design and construction work in Slobozhanshchyna and the functions of architectural and construction control and design. It provides examples of explanatory notes to the projects of religious buildings. The considered aspects of design and construction make it possible to assert that all these design and construction work methods aimed at creating highly sophisticated religious buildings. Keywords: design and construction work, religious buildings, architectural and construction control, explanatory note.

A NOVEL APPROACH TO SECURE WEB SEARCH: PROXY-QUERY BASED QUERY OBFUSCATION

Web search engines are used by people to access content on the internet. To improve the quality of the information received for individualized web searches, search engines keep query logs. User information, both sensitive and non-sensitive, is included in the query log. The query log can expose a great deal of personal information about a person and raise privacy issues if used against them. To achieve privacy-preserving online search, numerous private web search (PWS) systems have been proposed in recent years. While every PWS system claims to have special features that enable web search privacy (WSP), no study clarifies which properties related to private web searches should be taken into account when developing and implementing a PWS scheme. This article aims to accomplish two things. We introduce a new PWS strategy that employs a proxy-query-based query obfuscation method in the first section of the paper. In PWS research, proxy-query-based query obfuscation is a novel research area. Through proxy queries, it offers an IR tool for information retrieval from web search engines. The suggested system has the obvious benefit of preventing users from actually asking search engines questions in order to retrieve information. The second goal of the article is to identify PWS features and examine contemporary PWS systems in light of these attributes. We examined contemporary and suggested PWS systems based on PWS attributes. The investigation showed that only the suggested PWS design satisfies every requirement. Since existing PWS systems do not meet all PWS requirements, it has been found that they are susceptible to WSP attacks. Key Words: Private web search, Web search privacy, Proxy-query, Query Obfuscation, Information Retrieval, Cryptographic Authentication

Parameter Optimization of Josephson Parametric Amplifiers Using a Heuristic Search Algorithm for Axion Haloscope Search

The cavity haloscope is among the most widely adopted experimental platforms designed to detect dark matter axions with its principle relying on the conversion of axions into microwave photons in the presence of a strong magnetic field. The Josephson parametric amplifier (JPA), known for its quantum-limited noise characteristics, has been incorporated into the detection system to capture the weakly interacting axion signals. However, the performance of the JPA can be influenced by its environment, leading to the potential unreliability of a predefined parameter set obtained in a specific laboratory setting. Furthermore, conducting a broadband search requires the consecutive characterization of the amplifier across different tuning frequencies. To ensure more reliable measurements, we utilize the Nelder–Mead technique as a numerical search method to dynamically determine the optimal operating conditions. This heuristic search algorithm explores the multidimensional parameter space of the JPA, optimizing critical characteristics such as gain and noise temperature to maximize signal-to-noise ratios for a given experimental setup. Our study presents a comprehensive analysis of the properties of a flux-driven JPA to demonstrate the effectiveness of the algorithm. This approach contributes to ongoing efforts in axion dark matter research by offering an efficient method to enhance axion detection sensitivity through the optimized utilization of JPAs.

Extension of the Constantinou and Gani group contribution method with the Tochigi method through an automatic conversion procedure

Group contribution methods (GCMs) are widely employed across various disciplines to estimate compound properties when experimental data is lacking in the literature. While several methods exist, none are comprehensive, as they exhibit gaps either in functional groups or the predicted properties or simply do not offer the required accuracy. As a result, different methods may be necessary to evaluate distinct properties of the same compound. Typically, switching between these models is performed manually due to variations in the sets of functional groups employed. However, with the advancements in computational power and numerical optimum search, there is a growing need to automate the conversion between different group contribution methods. This study presents a procedure to extend the property estimation of the Constantinou and Gani method with vapor pressure by supplementing it with the Tochigi method using an automated group conversion algorithm. The difficulties of automatic conversion procedures, resulting from the differences in the group sets and the shortcomings of the GCMs, are also highlighted. It is also demonstrated that the accuracy of the acentric factor estimation can only be refined to a limited extent by incorporating the Tochigi method, which is, however, indispensable for the several groups where the Constantinou and Gani group contribution values are missing.

Climate Change and Socio-Economic Impacts: Determinants of Vulnerability for Developing Countries

Climate change is the connected system of solar cycle that creates fluctuations weather arrays across tropics to polls. Anticipated climate changes for the 21st century have been encountered complex challenges for humanity that significantly influence over diverse components such as environmental, ecological, socio-political and socio-economic systems among others. This study incorporates a desk literature review and at the first step researchers shortlisted the keywords regarding climate change, socioeconomic impacts and determinants of vulnerability. Mixed method approach applied for this desk review. Numerous online search engines such as Google, Google Scholar, Scopus, Web of Science and Springer were selected to review the published research studies. The collected data comprises on various forms such as book chapters, books, research articles, reports, working papers, organizational evaluation studies and conferences papers. After strict inclusion and exclusion criteria researchers gathered to 89 studies from 31 publications outlets, which were interrelated to different search engine and covering climate change impacts on developing countries. The findings endorsed the climate change socio-economic impacts are more sever particularly in developing countries of south Asia like Pakistan. The astonishing and spatial heterogeneities are the clear indications for comprehensive integrated interventions, policies and procedure to eliminate or reduce socio-economic climate change impacts of developing countries. Keywords: Climate change, Socio-economic impacts, Determinants of vulnerability, Environmental degradation, climate change and developing countries

TinyNS: Platform-Aware Neurosymbolic Auto Tiny Machine Learning.

Machine learning at the extreme edge has enabled a plethora of intelligent, time-critical, and remote applications. However, deploying interpretable artificial intelligence systems that can perform high-level symbolic reasoning and satisfy the underlying system rules and physics within the tight platform resource constraints is challenging. In this paper, we introduce TinyNS, the first platform-aware neurosymbolic architecture search framework for joint optimization of symbolic and neural operators. TinyNS provides recipes and parsers to automatically write microcontroller code for five types of neurosymbolic models, combining the context awareness and integrity of symbolic techniques with the robustness and performance of machine learning models. TinyNS uses a fast, gradient-free, black-box Bayesian optimizer over discontinuous, conditional, numeric, and categorical search spaces to find the best synergy of symbolic code and neural networks within the hardware resource budget. To guarantee deployability, TinyNS talks to the target hardware during the optimization process. We showcase the utility of TinyNS by deploying microcontroller-class neurosymbolic models through several case studies. In all use cases, TinyNS outperforms purely neural or purely symbolic approaches while guaranteeing execution on real hardware.

Towards efficient control synthesis for nonlinear wave energy conversion systems: impedance-matching meets the spectral-domain

Existing studies within the literature that focus on designing parametric energy-maximizing controllers for Wave Energy Converter (WEC) systems predominantly rely on the impedance-matching (IM) principle, originally developed for linear time-invariant systems. Alternatively, iterative optimization routines are commonly employed for nonlinear WECs. However, these approaches often face a trade-off between effectiveness in maximizing energy extraction and computational efficiency. To address this limitation, this study proposes a computationally efficient controller tuning method for analogous synthesis in the case of nonlinear WECs. The proposed approach combines a statistical linearization technique known as spectral-domain modeling with the IM principle, to synthesize a Proportional–Integrative (PI) controller for a nonlinear WEC. Furthermore, a comparison is performed with two other synthesis methods: one based on a standard (i.e. linear) frequency-domain representation of the WEC that incorporates the IM principle, and the other employing a gradient-free optimization routine applied to the nonlinear time-domain model of the WEC for PI parameter tuning through exhaustive numerical search. A discussion on the effectiveness of each tuning method in maximizing energy absorption is provided, including an appraisal of their associated computational time requirements. Numerical analyses demonstrate that the proposed method, which integrates spectral-domain modeling and IM, can achieve (almost) optimal PI controller design for a nonlinear WEC. Furthermore, this study addresses the inaccuracies inherent in the frequency-domain approach and significantly reduces the computational time compared to the exhaustive search procedure. The findings of this research represent a significant advancement towards the development of simple, effective, and efficient IM-based techniques for synthesis of controllers in nonlinear WEC systems

Systematic search for islets of stability in the standard map for large parameter values

In the seminal paper, Chirikov (Phys Rep 52:263–379, 1979) showed that the standard map does not exhibit a boundary to chaos, but rather that there are small islands (“islets”) of stability for arbitrarily large values of the nonlinear perturbation. In this context, he established that the area of the islets in the phase space and the range of parameter values where they exist should decay following power laws with exponents -2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-2$$\\end{document} and -1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-1$$\\end{document}, respectively. In this paper, we carry out a systematic numerical search for islets of stability and we show that the power laws predicted by Chirikov hold. Furthermore, we use high-resolution 3D islets to reveal that the islets’ volume decays following a similar power law with exponent -3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-3$$\\end{document}.

There are Salem Numbers with Trace –3 and Every Degree At Least 34

We prove that there exist Salem numbers with trace –3 and every even degree ≥ 34 . Our proof combines a theoretical approach, which allows us to treat all sufficiently large degrees, with a numerical search for small degrees. Since it is known that there are no Salem numbers of trace –3 and degree ≤ 30 , our result is optimal up to possibly the single value 32, for which it is expected there are no such numbers.

The Feel of Speech: Multisystem and Polymodal Somatosensation in Speech Production.

The oral structures such as the tongue and lips have remarkable somatosensory capacities, but understanding the roles of somatosensation in speech production requires a more comprehensive knowledge of somatosensation in the speech production system in its entirety, including the respiratory, laryngeal, and supralaryngeal subsystems. This review was conducted to summarize the system-wide somatosensory information available for speech production. The search was conducted with PubMed/Medline and Google Scholar for articles published until November 2023. Numerous search terms were used in conducting the review, which covered the topics of psychophysics, basic and clinical behavioral research, neuroanatomy, and neuroscience. The current understanding of speech somatosensation rests primarily on the two pillars of psychophysics and neuroscience. The confluence of polymodal afferent streams supports the development, maintenance, and refinement of speech production. Receptors are both canonical and noncanonical, with the latter occurring especially in the muscles innervated by the facial nerve. Somatosensory representation in the cortex is disproportionately large and provides for sensory interactions. Speech somatosensory function is robust over the lifespan, with possible declines in advanced aging. The understanding of somatosensation in speech disorders is largely disconnected from research and theory on speech production. A speech somatoscape is proposed as the generalized, system-wide sensation of speech production, with implications for speech development, speech motor control, and speech disorders.

Rediscovering the unusual, solitary bryozoan Monobryozoon ambulans Remane, 1936: first molecular and new morphological data clarify its phylogenetic position

BackgroundOne of the most peculiar groups of the mostly colonial phylum Bryozoa is the taxon Monobryozoon, whose name already implies non-colonial members of the phylum. Its peculiarity and highly unusual lifestyle as a meiobenthic clade living on sand grains has fascinated many biologists. In particular its systematic relationship to other bryozoans remains a mystery. Despite numerous searches for M. ambulans in its type locality Helgoland, a locality with a long-lasting marine station and tradition of numerous courses and workshops, it has never been reencountered until today. Here we report the first observations of this almost mythical species, Monobryozoon ambulans.ResultsFor the first time since 1938, we present new modern, morphological analyses of this species as well as the first ever molecular data. Our detailed morphological analysis confirms most previous descriptions, but also ascertains the presence of special ambulatory polymorphic zooids. We consider these as bud anlagen that ultimately consecutively separate from the animal rendering it pseudo-colonial. The remaining morphological data show strong ties to alcyonidioidean ctenostome bryozoans. Our morphological data is in accordance with the phylogenomic analysis, which clusters it with species of Alcyonidium as a sister group to multiporate ctenostomes. Divergence time estimation and ancestral state reconstruction recover the solitary state of M. ambulans as a derived character that probably evolved in the Late Cretaceous. In this study, we also provide the entire mitogenome of M. ambulans, which—despite the momentary lack of comparable data—provides important data of a unique and rare species for comparative aspects in the future.ConclusionsWe were able to provide first sequence data and modern morphological data for the unique bryozoan, M. ambulans, which are both supporting an alcyonidioidean relationship within ctenostome bryozoans.

An explicit 16-stage Runge–Kutta method of order 10 discovered by numerical search

An explicit 16-stage Runge–Kutta method of order 10 discovered by numerical search

Research integrity and academic medicine: the pressure to publish and research misconduct.

This narrative review article explores research integrity and the implications of scholarly work in medical education. The paper describes how the current landscape of medical education emphasizes research and scholarly activity for medical students, resident physicians, and faculty physician educators. There is a gap in the existing literature that fully explores research integrity, the challenges surrounding the significant pressure to perform scholarly activity, and the potential for ethical lapses by those involved in medical education. The objectives of this review article are to provide a background on authorship and publication safeguards, outline common types of research misconduct, describe the implications of publication in medical education, discuss the consequences of ethical breaches, and outline possible solutions to promote research integrity in academic medicine. To complete this narrative review, the authors explored the current literature utilizing multiple databases beginning in June of 2021, and they completed the literature review in January of 2023. To capture the wide scope of the review, numerous searches were performed. A number of Medical Subject Headings (MeSH) terms were utilized to identify relevant articles. The MeSH terms included "scientific misconduct," "research misconduct," "authorship," "plagiarism," "biomedical research/ethics," "faculty, medical," "fellowships and scholarships," and "internship and residency." Additional references were accessed to include medical school and residency accreditation standards, residency match statistics, regulatory guidelines, and standard definitions. Within the realm of academic medicine, research misconduct and misrepresentation continue to occur without clear solutions. There is a wide range of severity in breaches of research integrity, ranging from minor infractions to fraud. Throughout the medical education system in the United States, there is pressure to publish research and scholarly work. Higher rates of publications are associated with a successful residency match for students and academic promotion for faculty physicians. For those who participate in research misconduct, there is a multitude of potential adverse consequences. Potential solutions to ensure research integrity exist but are not without barriers to implementation. Pressure in the world of academic medicine to publish contributes to the potential for research misconduct and authorship misrepresentation. Lapses in research integrity can result in a wide range of potentially adverse consequences for the offender, their institution, the scientific community, and the public. If adopted, universal research integrity policies and procedures could make major strides in eliminating research misconduct in the realm of academic medicine.