Search Procedure Research Articles

Particle swarm optimization with local search for height-map surface reconstruction from point clouds in reverse engineering

AbstractSurface reconstruction is a classical process in industrial engineering and manufacturing, particularly in reverse engineering, where the goal is to obtain a digital model from a physical object. For that purpose, the real object is typically scanned or digitized and the resulting point cloud is then fitted to mathematical surfaces through numerical optimization. The choice of the approximating functions is crucial for the accuracy of the process. Real-world objects such as manufactured workpieces often require complex nonlinear approximating functions, which are not well suited for standard numerical methods. In a previous paper presented at the ISMSI 2023 conference, we addressed this issue by using manually selected approximation functions via optimization through the cuckoo search algorithm with Lévy flights. Building upon that work, this paper presents an enhanced and extended method for surface reconstruction by using height-map surfaces obtained through a combination of exponential, polynomial and logarithmic functions. A feasible approach for this goal is to consider continuous bivariate distribution functions, which ensures consistent models along with good mathematical properties for the output shapes, such as smoothness and integrability. However, this approach leads to a difficult multivariate, constrained, multimodal continuous nonlinear optimization problem. To tackle this issue, we apply particle swarm optimization, a popular swarm intelligence technique for continuous optimization. The method is hybridized with a local search procedure for further improvement of the solutions and applied to a benchmark of 15 illustrative examples of point clouds fitted to different surface models. The performance of the method is analyzed through several computational experiments. The numerical and graphical results show that the method is able to recover the shape of the point clouds accurately and automatically. Furthermore, our approach outperforms other alternative methods significantly in terms of the numerical errors. We conclude that our method can be successfully applied to the reconstruction of manufactured workpieces in real industrial settings.

Polysaccharide-Based Drug Carriers—A Patent Analysis

Polysaccharide-based carriers as biomaterials for drug delivery have been inspiring scientists for years due to their exceptional characteristics, such as nontoxicity, biocompatibility, and degradability, as they are able to protect pharmaceutically active molecules and provide their controlled/modified release. This review focuses on selected drug delivery systems based on natural polymers, namely fucoidan, pullulan, dextran, and pectin, with the aim of highlighting published patent documents. The information contained in patents is very important because it is usually not published in any other document and is much less discussed as the state of the art in the scientific literature. The Espacenet—European Patent Office database and the International Patent Classification were used for the research to highlight the specific search procedure. The presented analysis of the innovative state of the art includes an overview from the first patent applications to the latest granted patents in this field.

A systematic review of multi-level intervention to enhance the quality of life patient with human immunodeficiency virus

Human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) are still challenges worldwide. Improvement in quality of life (QoL) is crucial for HIV-infected people. The QoL of HIV-infected patients has been improved by the use of multilevel interventions in various circumstances. This study evaluates the evidence for interventions that target the quality of life of persons with HIV. A systematic review was performed according to the PRISMA guidelines. Science Direct, the Cochrane Library database, and Pubmed were also searched. Three independent reviewers extracted the data. Searches were conducted for articles published from 2013 to 2023. Searching procedures and data abstraction techniques were standardized. The 27 research examined the effects of interventions on HIVinfected people's quality of life. China is the most frequently mentioned country in the 27 studies, appearing as the setting in 8 (29.6%). Following South Africa (14.8%), New York (11.11%) and Kenya (7.4%) were the next most often mentioned countries. For analysis purposes, the interventions used in the 27 reviewed studies were classified into three main categories: individual intervention, family-community intervention, and health service intervention. Significant intervention innovations in quality-of-life research combining several interventions, including individual, family, community, and health system intervention, show the most promising results

Identification of fractional-order transfer functions and nonzero initial conditions using exponentially modulated signals

Abstract A new methodology that uses exponentially modulated signals with arbitrary excitation waveforms for the identification of fractional order transfer functions is proposed. In contrast to previous approaches where initial conditions were not considered and the system was required to be at rest for the identification procedure, the current contribution extends the formulation to the case where the system has non-zero initial conditions, dispensing with the need to place it at a resting state. This generalization is important in feedback instrumentation and metrology applications where the measurement or control process may not be disrupted to perform identification. Moreover, the procedure has a broader scope of applications because it structurally contemplates the case when the model presents derivatives in the input. Full identification of the system parameters as well as the fractional exponents associated with the model dynamics are achieved through a grid search procedure with resolution adjustable by the user. Two simulation examples are presented to illustrate the effectiveness of the proposed approach. The first example is concerned with the effect of measurement noise at the observed system output, whereas the second involves the identification of the impedance of a three-dimensional RC network model. These types of RC networks
have dynamics capturing complex phenomena with emergent responses and are ideal for emulating the complex dynamics encountered across physical sciences and in particular interdisciplinary subject areas such as biomedical engineering.

An Improved Hybrid Genetic-Hierarchical Algorithm for the Quadratic Assignment Problem

In this paper, an improved hybrid genetic-hierarchical algorithm for the solution of the quadratic assignment problem (QAP) is presented. The algorithm is based on the genetic search combined with the hierarchical (hierarchicity-based multi-level) iterated tabu search procedure. The following are two main scientific contributions of the paper: (i) the enhanced two-level hybrid primary (master)-secondary (slave) genetic algorithm is proposed; (ii) the augmented universalized multi-strategy perturbation (mutation process)—which is integrated within a multi-level hierarchical iterated tabu search algorithm—is implemented. The proposed scheme enables efficient balance between intensification and diversification in the search process. The computational experiments have been conducted using QAP instances of sizes up to 729. The results from the experiments with the improved algorithm demonstrate the outstanding performance of the new proposed approach. This is especially obvious for the small- and medium-sized instances. Nearly 90% of the runs resulted in (pseudo-)optimal solutions. Three new best-known solutions have been achieved for very hard, challenging QAP instances.

THE (IN)VIABILITY OF SUBSTANTIAL COMPLIANCE AS A MEANS OF DEFENSE IN THE EXTRAJUDICIAL SEARCH AND SEIZURE OF A VEHICLE IN THE RTD

This article examines whether the claim of substantial performance is a possible means of defense in the extrajudicial search and seizure procedure for vehicle fiduciary sale at the Registry of Deeds and Documents (RTD), included in Decree-Law 911/2023, by the New Guarantee Law. To this end, it analyzes aspects of the constitutionality of the new procedure in light of the judgments of the Supreme Federal Court regarding the extrajudicial execution of mortgages (RE 627,106) and the fiduciary sale of real estate (RE 860,631). It then establishes that objective good faith is the meta-legal premise of substantial performance, studying its (in)compatibility with the claim of substantial performance in the enforcement procedure at the RTD. It presents doctrinal views on the theory of substantial performance, with evidence of its acceptance in the Brazilian legal system. Next, it summarizes the extrajudicial search and seizure procedure, according to the new legislation, drawing a parallel with the already consolidated jurisprudence, regarding similar procedures. It moves on to the analysis of the results, whose comparison points to the inadmissibility of the claim of substantial fulfillment, both in judicial proceedings and even more so in extrajudicial proceedings, given the summary cognition of the registrar, in the search and seizure procedure of the fiduciary alienation in vehicles.

Processing cataphoric they amidst pronominal innovation

When they encounter a cataphoric pronoun during real-time sentence processing, the comprehender begins searching actively for a feature-matched noun that can supply its reference. The present study investigates individual variation in this active search procedure, leveraging an ongoing change in the pronoun system of North American English. The types of referents compatible with the they-series of pronouns is expanding, with an increasing number of speakers allowing definite singular referents: especially but not exclusively when referring to someone with a nonbinary gender identity. Sociolinguistic work shows that the speakers who most accept innovative usages of singular they tend to be younger, or to be non-cisgender (e.g. transgender, nonbinary). Recruiting participants representing diverse ages and gender identities, the present experiment tracked reading times of sentences involving cataphora. Results shows that cataphoric they is processed differently than cataphoric s/he, across the board. There is a significant processing cost to reading a plural noun that follows cataphoric s/he, indicating that singular cataphors evoke strong number expectations. However, the cost of reading a singular noun after they is smaller and emerges later; they seems to evoke weak number expectations. Individual differences show that those expectations are especially weak for younger participants, perhaps reflecting a higher baseline familiarity with singular they. On the other hand, course-grained gender identity (cis vs. non-cis) does not seem to be a reliable predictor of how cataphoric they is processed. Integrating insights from sociolinguistics and psycholinguistics, this study offers a novel view into ongoing language change and its manifestation in real-time processing measures.

Two RMIL-type schemes with compressed sensing applications

It has been proven that the conjugate gradient (CG) method by Rivaie, Mustafa, Ismail and Leong (RMIL) (Appl. Math. Comput. 218 (2012) 11323–11332), does not satisfy the sufficient descent condition, and its global convergence is attained only by employing the exact line search (ELS) procedure. In this study, two RMIL-type algorithms are proposed for system of monotone nonlinear equations, where both properties hold regardless of the line search strategy used. Two approximations of the nonnegative parameter that is embedded in search directions of the algorithms are determined by analysing eigenvalues and singular values of their iteration matrices. The new solvers are also ideal for nonsmooth problems. Four recent solvers are employed to show effectiveness of the new methods. Furthermore, the schemes are used to solve some signal and image recovery problems.

Dynamic Buffer Management in Massively Parallel Systems: The Power of Randomness

Massively parallel systems, such as Graphics Processing Units (GPUs), play an increasingly crucial role in today’s data-intensive computing. The unique challenges associated with developing system software for massively parallel hardware to support numerous parallel threads efficiently are of paramount importance. One such challenge is the design of a dynamic memory allocator to allocate memory at runtime. Traditionally, memory allocators have relied on maintaining a global data structure, such as a queue of free pages. However, in the context of massively parallel systems, accessing such global data structures can quickly become a bottleneck even with multiple queues in place. This paper presents a novel approach to dynamic memory allocation that eliminates the need for a centralized data structure. Our proposed approach revolves around letting threads employ random search procedures to locate free pages. Through mathematical proofs and extensive experiments, we demonstrate that the basic random search design achieves lower latency than the best-known existing solution, Ouroboros, in most situations. Furthermore, we develop more advanced techniques and algorithms to tackle the challenge of warp divergence and further enhance performance when free memory is limited. Building upon these advancements, our mathematical proofs and experimental results affirm that these advanced designs can yield an order of magnitude improvement over the basic design and consistently outperform the state-of-the-art by up to two orders of magnitude. To illustrate the practical implications of our work, we integrate our memory management techniques into two GPU algorithms: a hash join and a group-by. Both case studies provide compelling evidence of our approach’s pronounced performance gains.

Followership is not following: reframing followership in western higher education

ABSTRACT This article examined the meanings of followership in Western higher education as reported in the literature. To retrieve sources, an electronic search was implemented. The search procedure included the terms ‘followership’ and ‘education’ on six databases and other sources. Examination of relevant works found that, in Western higher education, ‘followership’ takes a different meaning than what is currently reported in the literature. Views of self-control and agency and strong notions of autonomy and independence surfaced, aligning with academic ideas of critical and independent thinking, and academic freedom. Indeed, many academics did not align with the idea of being a follower as well as the perspective of followership as the deference to another individual. It was revealed that what academics do in Western higher education cannot be described by the term ‘followership’. In this context, ‘followership’ is more accurately described as an endeavor related to contribution and making a difference; thus, a case for an afresh term was made. It was argued that a new term should acknowledge academics’ autonomy and independence, and that academics ‘volunteer’ but do not ‘subordinate’. Resultantly, the term ‘endeavorship’ was offered.

A GRASP-based multi-objective approach for the tuna purse seine fishing fleet routing problem

Nowadays, the world’s fishing fleet uses 20% more fuel to catch the same amount of fish compared to 30 years ago. Addressing this negative environmental and economic performance is crucial due to stricter emission regulations, rising fuel costs, and predicted declines in fish biomass and body sizes due to climate change. Investment in more efficient engines, larger ships and better fuel has been the main response, but this is only feasible in the long term at high infrastructure cost. An alternative is to optimize operations such as the routing of a fleet, which is an extremely complex problem due to its dynamic (time-dependent) moving target characteristics. To date, no other scientific work has approached this problem in its full complexity, i.e., as a dynamic vehicle routing problem with multiple time windows and moving targets. In this paper, two bi-objective mixed linear integer programming (MIP) models are presented, one for the static variant and another for the time-dependent variant. The bi-objective approaches allow to trade off the economic (e.g., probability of high catches) and environmental (e.g., fuel consumption) objectives. To overcome the limitations of exact solutions of the MIP models, a greedy randomized adaptive search procedure for the multi-objective problem (MO-GRASP) is proposed. The computational experiments demonstrate the good performance of the MO-GRASP algorithm with clearly different results when the importance of each objective is varied. In addition, computational experiments conducted on historical data prove the feasibility of applying the MO-GRASP algorithm in a real context and explore the benefits of joint planning (collaborative approach) compared to a non-collaborative strategy. Collaborative approaches enable the definition of better routes that may select slightly worse fishing and planting areas (2.9%), but in exchange for a significant reduction in fuel consumption (17.3%) and time at sea (10.1%) compared to non-collaborative strategies. The final experiment examines the importance of the collaborative approach when the number of available drifting fishing aggregation devices (dFADs) per vessel is reduced.

SEMANTICS AND MEANING OF TERMS WITH THE COMPONENT ’RED’

The article provides an analysis of the results of a study on the semantics and meanings of terms with the component red in modern Bulgarian. The language material on which basis the study was carried out is an electronic corpus of Bulgarian language texts compiled from publicly available internet sources. Statistical approaches to search for concordances and collocations available through the Sketch Engine lexicographic software were used to discover the terms in the corpus, and the order in the search procedures (algorithm) was previously tested in other cited studies. The theoretical approach of the study involves tracing the semantics and meanings of terms for the color red and terms with the component red using both traditional approaches such as the theory of nomination (by detection of the main semantic component), and modern theories, such as the theory of prototypes (by evaluation of color’s prototypes) in the analysis of the semantics of these terms. Results and examples of high-frequency contextual corpus usages of red are provided to analyze the terms’ semantics and meanings both as a color term and terms with other (non-color) meanings (prototypes and terms of the basic features of the prototypes), and related conclusions on semantics and meanings of these terms are provided. The color component of the terms at issue is interpreted in the context of a broader understanding of color (such as macro-color), in its transition to other colors, and it is also noted that those terms relate to similar terms with a color component, for example white, establishing a semantic relation through the macro-color component.

Perceived Control as a Potential Protective Factor for Suicidal Thoughts and Behaviors in Cancer Patients and Survivors: A Systematic Review With Meta-Analysis.

Individuals affected by cancer have an elevated risk of experiencing suicidal crises. Aligning established suicide theories with social-cognitive theories, perceived control and related constructs emerge as potential protective factors for suicidal thoughts and behaviors in cancer patients. As perceived control is potentially modifiable, it holds great potential for prevention and intervention efforts. We aimed to comprehensively synthesize the evidence on perceived control and its link with suicidal thoughts and behaviors in cancer patients. The search term and procedures were registered in PROSPERO (CRD42023391048). We systematically searched the databases PubMed/MEDLINE, CINAHL, PsycInfo, Web-of-Science Core Collection, Cochrane Library, adding a grey literature search. In addition to the narrative review, pooled effect sizes, moderation and subgroup analysis were calculated. The systematic search yielded 1986 original reports of which 36 were included in the systematic review and 25 in the meta-analysis. Demoralization, help-/hopelessness, and self-efficacy were the most commonly studied facets of control, showing a relatively large, pooled correlation with suicidal ideation overall (r=0.45, [95% CI=0.38-0.52], Q=346.15, p<0.01, I2=91.2%) and across operationalisations (demoralisation: r=52; hopelessness: r=45; self-efficacy: r=0.40). Moderation analyses revealed no effect of cancer stages; but more directly cancer-associated variables (demoralisation, hopelessness) were more closely related to suicidal ideation (QM=5.40, p=0.02) than general self-efficacy. The findings underscore the pivotal role of perceived control in shaping severe distress in cancer patients. More studies are needed examining perceived control in a narrower sense.

Hierarchical meta-porous materials as sound absorbers

The absorption of sound has great significance in many scientific and engineering applications, from room acoustics to noise mitigation. In this context, porous materials have emerged as a viable solution towards high absorption performance and lightweight designs. However, their performance is somewhat limited in the low-frequency regime. Inspired by the concept of recursive patterns over multiple length scales, typical of many natural materials, here, we propose a hierarchical organization of multilayered porous media and investigate their performance in terms of sound absorption. Two types of designs are considered: a hierarchical periodic (HP) and a hierarchical gradient (HG). In both cases, it is found that in some frequency ranges the introduction of multiple levels of hierarchy simultaneously allows for: (i) an increase in the level of absorption compared with the corresponding bulk block of porous material (or to the previous hierarchical levels (HLs)), and (ii) a reduction in the quantity of porous material required. Another advantage of using this approach is on the fabrication, since only one porous material is required. The performances are examined for both normal and oblique incidences, as well as for different values of the static air-flow resistivity. The methodological approach is based on the transfer-matrix method, optimization algorithms such as the metaheuristic greedy randomized adaptive search procedure (GRASP), finite-element calculations and measurements performed in an impedance tube.

Efficacy of different warming methods for perioperative hypothermia prevention on body temperature and shivering among transurethral resection patients: A systematic review and meta-analysis study

PurposeThe present study attempts to assess the impacts of distinct warming strategies employed to avert perioperative hypothermia on core body temperature and shivering among transurethral resection patients. MethodsWe performed a comprehensive search of Turkish and English keywords across a range of databases, including PUBMED, Web of Science, Cochrane Library, SCOPUS, Ovid, EBSCOhost, Yöktez, DergiPark, and TR Index, to identify studies on the subject published between January 1, 2001–2024. The search procedure yielded 11 studies to be recruited for meta-analysis. We analyzed the data using the trial version of Comprehensive Meta-Analysis Software (CMA). The degree of heterogeneity was quantified using Higgins I2 tests, while we assessed publication bias through Kendall's Tau and Egger's regression analyses. ResultsThis meta-analysis focuses exclusively on the effects of forced air warming and irrigation fluid warming, as only these methods provided sufficient data to calculate effect size. Our findings demonstrated that while forced air warming significantly affected preoperative (g = 0.279), intraoperative (15th minute, T4) (g = 0.845), postoperative (g = 0.647) body temperature and postoperative shivering (g = −2.279), irrigation fluid warming had a significant impact on postoperative body temperature (g = 1.007) and intraoperative shivering (g = 0.188). ConclusionOverall, our results indicated that forced air warming and irrigation fluid warming can serve as a preventive measure against hypothermia and shivering among transurethral resection patients. Given that other forms of warming could not be included in this research, further studies are recommended to explore scholarly evidence on the efficacy of these methods.

BWBEV: A Bitwise Query Processing Algorithm for Approximate Prefix Search

We tackle the challenge of conducting an approximate prefix search within datasets of strings. We explore using a bit-parallelism technique to compute the edit distance between distinct strings and illustrate its adaptation for an approximate prefix search procedure referred to as BWBEV. This technique employs a unary representation of edit vectors alongside bitwise operations to efficiently update these vectors during the edit distance computation. We also show how to apply our new bit-parallelism technique strategy to online edit distance computation between strings without index structure. Our experiments with BWBEV applied to approximate prefix search for a query autocompletion task revealed a substantial acceleration of over 36% when contrasted against state-of-the-art methods.

Model for Predicting Maize Crop Yield on Small Farms Using Clusterwise Linear Regression and GRASP

Planting a crop involves several key steps: resource assessment, crop selection, crop rotation, planting schedules, soil preparation, planting, care, and harvesting of crops. In this context, estimating the productivity of a crop based on available information, such as expected climatic conditions and agricultural practices, helps farmers reduce the uncertainty of their investment. In Colombia, maize is the fourth most important crop in the country. Significant efforts are required to improve productivity in traditional and technified production systems. In this sense, this research proposes and evaluates an approach called Clusterwise Linear Regression (CLR) to predict the crop maize yield in small farms, considering data on climate, soil, fertilization, and management practices, among others. To develop the CLR model, we conducted the following steps: data collection and preparation, clustering using k-means, cluster optimization with Greedy Random Adaptive Search Procedure (GRASP), and performance evaluation. The cluster optimization process allows the identification of clusters with similar characteristics and generates multiple linear regression models with mixed variables that explain the yield of the farms on each cluster. The Simulated Multiple Start Annealing (MSSA) metaheuristics were also evaluated, but the results of GRASP were the best. The results indicate that the proposed CLR approach is more effective than the linear and nonlinear algorithms mentioned in the literature, such as multiple lasso linear regression, random forests, XGBoost, and support vector machines. These algorithms achieved an accuracy of 70%. However, with the new CLR model, a significantly improved accuracy of 87% was achieved with test data. The clusters’ studies revealed key factors affecting crop yield, such as fertilization, drainage, and soil type. This transparency is a benefit over black-box models, which can be harder to interpret. This advancement can allow farmers to make better decisions about the management of their crops.

Memoization in Model Checking for Safety Properties with Multi-Swarm Particle Swarm Optimization

In software engineering, errors or faults in software systems often lead to critical social problems. One effective methodology to tackle this problem is model checking, which is an automated formal verification technique. In traditional model checking, the task of finding specification errors is reduced to deterministic search techniques such as Depth-First Search. Recent research has shown that swarm intelligence offers a powerful search capability compared to traditional techniques. In particular, multi-swarm Particle Swarm Optimization is known to be efficient and can mitigate the state-space explosion problem, i.e., the exponential increase in the search space with a linear increase in the problem size. However, the state-space explosion problem is still significant when verifying very large systems. Further performance improvement is needed. To achieve this, we propose a novel memoization or cache mechanism for storing tentative solutions for reuse in the later stages of the search procedure. For each stage, a candidate solution computed by a swarm is summarized efficiently and heuristically to consolidate similar solutions into a single representative solution. We store the summary and its associated solutions in key-value maps. Instead of computing known solutions repeatedly, we retrieve the solution if the stored key matches the summary. We incorporated the proposed mechanism into a model-checking technique with multi-swarm Particle Swarm Optimization and evaluated the search performance. We show in this paper that the proposed mechanism improved time and space consumption while maintaining solution quality.

Prediction of crystal structures and superconductivity of actinium borides at high pressures

Abstract To investigate potential compounds that may emerge in actinium borides at high-pressure conditions. In this work, we carried out systematic crystal structure search procedure on the Ac-B compounds from 0 to 300 GPa conditions based on evolutionary algorithms and density functional theory (DFT). We discovered a stable phase AcB6 at 0 GPa with common structure of hexaboride and three phases AcB, AcB8 and Ac2B11 at higher pressures in the Ac-B system. Our results show that Ac2B11 exhibits a Vickers hardness of approximately 31 GPa and a superconducting transition temperature Tc of 14.4 K at 0 GPa. The structure of Ac2B11 resembles a middle phase evolving from the hexaboride AcB6 towards a class of pentaboride structures, characterized by the formation of a B22 cage structure resulting from further boron enrichment based on the B20 cage, or derived from the partial dimerization of the B24 cage found in hexaborides. We believe that this configuration may hold significant potential as a parent matrix for the design of interesting ultra-hard materials with relatively high superconducting transition temperatures.&amp;#xD;

Software architecture-based self-adaptation in robotics

Context:Robotics software architecture-based self-adaptive systems (RSASSs) are robotics systems made robust to runtime uncertainty by adapting their software architectures. The research landscape of RSASS approaches is multidisciplinary and fragmented, with many aspects still unexplored or ineffectively shared among communities involved. Objective:We aim at identifying, classifying, and analyzing the state of the art of existing approaches for RSASSs from the following perspectives: (i) the key characteristics of approaches and (ii) the evaluation strategies applied by researchers. Method:We apply the systematic mapping research method. We selected 37 primary studies via automatic, manual, and snowballing-based search and selection procedures. We rigorously defined and applied a classification framework composed of 32 parameters and synthesize the obtained data to produce a comprehensive overview of the state of the art. Results:This work contributes (i) a rigorously defined classification framework for studies on RSASSs, (ii) a systematic map of the research efforts on RSASSs, (iii) a discussion of emerging findings and implications for future research, and (iv) a publicly available replication package. Conclusion:This study provides a solid evidence-based overview of the state of the art in RSASS approaches. Its results can benefit RSASS researchers at different levels of seniority and involvement in RSASS research.Editor’s note: Open Science material was validated by the Journal of Systems and Software Open Science Board.