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In recent decades, the field of robotic mapping has witnessed widespread research and development in light detection and ranging (LiDAR)-based simultaneous localization and mapping (SLAM) techniques. This paper aims to provide a significant reference for researchers and engineers in robotic mapping.

This paper focused on the research state of LiDAR-based SLAM for robotic mapping as well as a literature survey from the perspective of various LiDAR types and configurations.

This paper conducted a comprehensive literature review of the LiDAR-based SLAM system based on three distinct LiDAR forms and configurations. The authors concluded that multi-robot collaborative mapping and multi-source fusion SLAM systems based on 3D LiDAR with deep learning will be new trends in the future.

To the best of the authors’ knowledge, this is the first thorough survey of robotic mapping from the perspective of various LiDAR types and configurations. It can serve as a theoretical and practical guide for the advancement of academic and industrial robot mapping.

Over the decades, simultaneous localization and mapping (SLAM) techniques have been extensively researched and applied in robotic mapping. In complex environments, SLAM systems using a single sensor, such as a camera or light detection and ranging (LiDAR), often cannot meet the accuracy and map consistency requirements. This study aims to propose a tightly-coupled LiDAR-inertial SLAM system, which aims to achieve higher accuracy and map consistency for robotic mapping in complex environments.

This paper presents TC-Mapper, a tightly coupled LiDAR-inertial SLAM system based on LIO-SAM. The authors introduce the normal distribution-based loop closure detection method to the original one (i.e. the radius search-based method), which can enhance the accuracy and map consistency for robotic mapping. To further suppress map drift in complex environments, this paper incorporates a gravity factor into the original factor graph. In addition, TC-Mapper introduces incremental voxels (iVox) as the point cloud spatial data structure.

Extensive experiments in public and self-collected data sets demonstrate that TC-Mapper has high accuracy and map consistency.

TC-Mapper has two types of loop closure detections: the normal distribution-based method for correcting large drifts and the radius search-based method for fine-stitching, which can achieve higher accuracy and map consistency. The authors introduce iVox as the point cloud spatial data structure, which strives to attain a balance between precision and efficiency to the greatest extent feasible.

Current practices for inspecting highway construction predominantly rely on manual processes, which result in subjective assessments, errors and time inefficiencies. The purpose of this study is to address the inefficiencies and potential inaccuracies inherent in manual highway construction inspections. By leveraging computer vision and ontology reasoning, the study seeks an automated and efficient approach to generate structured construction inspection knowledge in the format of checklists for construction activities on highway construction job sites.

This study proposes a four-module framework based on computer vision and ontology reasoning to enable the automatic generation of checklists for quality inspection. The framework includes: (1) the interpretation of construction scenes based on computer vision, (2) the representation of inspection knowledge into structured checklists through specification processing, (3) the connection of construction scenes and inspection knowledge via ontology reasoning and (4) the development of a prototype for the automatic generation of checklists for highway construction.

The proposed framework is implemented across four distinct highway construction scenarios. The case demonstrations show that the framework can interpret construction scenes and link them with relevant inspection knowledge automatically, resulting in the efficient generation of structured checklists. Therefore, the proposed framework indicates considerable potential for application in the automatic generation of inspection knowledge for the quality inspection of highway construction.

The scientific and practical values of this study are: (1) the establishment of a new method that promotes the automated generation of structured inspection knowledge for highway construction by integrating computer vision and ontology reasoning and (2) the development of a novel framework that provides efficient and immediate access to inspection knowledge related to what needs to be inspected at highway construction job sites.

The importance of the agri-food supply chain in both food production and distribution has made the issue of its development a critical concern. Based on configuration theory and congruence theory, this research investigates the complex impact of supply chain concentration on financial growth in agri-food supply chains.

The cluster analysis and response surface methodology are employed to analyse the data collected from 207 Chinese agri-food companies from 2010 to 2022.

The results indicate that different combination patterns of supply chain concentration can lead to different levels of financial growth. We discover that congruent supplier and customer concentration is beneficial for companies’ financial growth. This impact is more pronounced when the company is in the agricultural production stage of agri-food supply chains. Post-hoc analysis indicates that there exists an inverted U-shaped relationship between the overall levels of supply chain concentration and financial growth.

Our research uncovers the complex interplay between supply chain base and financial outcomes, thereby revealing significant ramifications for agri-food supply chain managers to optimise their strategies for exceptional financial growth.

This study proposes a combined approach of cluster analysis and response surface analysis for analysing configuration issues in supply chain management.

This paper aims to report the influence of hexamethylenetetramine (HMTA) on phosphate coatings formed on AZ31 magnesium alloys.

These phosphate coatings were obtained by immersing magnesium alloys in phosphate baths with HMTA. The morphology and composition of the phosphate coatings were investigated via scanning electron microscopy, energy dispersive spectrometry and X-ray diffraction.

The phosphate coatings were mainly composed of CaHPO₄·2H₂O. The HMTA concentration in the phosphate bath influenced the crystallization and corrosion resistance of the phosphate coating.

The polarization curve shows that the anti-corrosion qualities of the phosphate coating were optimal when the HMTA concentration was 1.0 g/L in the phosphate bath. Electrochemical impedance spectroscopy (EIS) shows that the electrochemical impedances increased gradually when the HMTA concentration varied from 1.0 to 3.0 g/L.

This article estimates the loan spread equation taking into account the endogenous matching between banks and firms in the loan market. To overcome the endogeneity problem, I supplement the loan spread equation with a two-sided matching model and estimate them jointly. Bayesian inference is feasible using a Gibbs sampling algorithm that performs Markov chain Monte Carlo (MCMC) simulations. I find that medium-sized banks and firms tend to be the most attractive partners, and that liquidity is also a consideration in choosing partners. Furthermore, banks with higher monitoring ability charge higher spreads, and firms that are more leveraged or less liquid are charged higher spreads.

Keberkesanan penyampaian sesuatu maklumat memerlukan individu, alat mahupun saluran yang unggul dan bersesuaian. Usaha ini haruslah dirancang dan dipertimbangkan dengan teliti oleh pihak tertentu agar setiap apa yang ingin disampaikan dan dilaksanakan itu dapat diberigakan dengan mudah dan berkesan. Dari itu, penggunaan bahasa retorik dilihat sebagai batu loncatan yang memberikan keyakinan dan tahap keberkesanan yang tinggi bagi sesebuah wacana yang disampaikan tersebut. Kewibawaan retorik sebagai seni yang mempengaruhi bukan sahaja berperanan untuk memperkukuhkan kekuasaan mahupun mempengaruhi fikiran dan emosi orang lain namun sebaliknya mampu menstimulasikan keseimbangan hubungan sosial yang terbentuk melalui sistem pemerintahan sesebuah negara. Melalui penyelidikan ini, setiap ciri khas retorik dapat diketengahkan dengan menghuraikan peranan dan fungsi-fungsi yang dimainkan oleh jenis-jenis retorik dalam penulisan sesebuah wacana. Hal ini khusus bagi mengilustrasikan idea, gagasan mahupun suatu fakta terhadap sesuatu pendekatan dengan cara yang kreatif dan terbaik. Di samping itu, keutamaan bagi penerapan bahasa retorik dalam perutusan kerajaan seharusnya dapat diperkasakan sewajarnya dengan menjadikannya sebagai anjakan paradigma ke arah perpaduan dan nilai kesaksamaan dalam masyarakat. Justeru, kajian ini memanfaatkan Teori Retorik Moden oleh Enos dan Brown (1993) sebagai landasan utama dalam menganalisis sejumlah 20 perutusan rasmi berkaitan jangkitan covid-19 di Negara Brunei Darussalam. Berdasarkan pemerhatian dan penganalisisan yang dijalankan, hanya empat jenis retorik yang diaplikasikan dalam wacana tersebut. Kesimpulan statistik merangkumi 34% teknik pendedahan, 30% teknik penerangan, 33% teknik pemujukan dan hanya 3% bagi teknik penghujahan. Dapatan penyelidikan ini membuktikan bahawa penggunaan bahasa retorik dalam perutusan rasmi kerajaan adalah amat penting dalam memperkukuhkan sistem pemerintahan negara serta mampu melestarikan cara hidup yang relevan dan berkualiti.

The effectiveness of delivering information requiresindividuals, tools or channels that are superior and appropriate. This effort must be planned and considered carefully so that everything that is to be conveyed and implemented can be conveyed easily and effectively. Therefore, the use of rhetorical language is regarded as a stepping stone that provides confidence and a higher level of effectiveness. `Rhetoric as an influential art not only plays a role in strengthening power or influencing the thoughts and emotions of others but also stimulate sthe balance of social relations. Through this research, each rhetorical feature is highlighted to discuss its role and functions in the discourse. Using Enos and Brown’s Modern Rhetorical Theory (1993), a total of 20 official conferences on the latest developments of the spread of covid-19 infection were discussed. Findings have shown that there were four main types of rhetoric, i.e. Statistical conclusions which include 34% of expository techniques, 30% of descriptive, 33% of persuasion and only 3% for argumentation techniques. This also implies that rhetoric language is very important in ensuring the dissemination of knowledge among the institution and people is effective and and transparent.

This paper aims to present a novel hybrid time integration approach for efficient numerical simulations of multiscale problems involving interactions of electromagnetic fields with fine structures.

The entire computational domain is discretized with a coarse grid and a locally refined subgrid containing the tiny objects. On the coarse grid, the time integration of Maxwell’s equations is realized by the conventional finite-difference technique, while on the subgrid, the unconditionally stable Krylov-subspace-exponential method is adopted to breakthrough the Courant–Friedrichs–Lewy stability condition.

It is shown that in contrast with the conventional finite-difference time-domain method, the proposed approach significantly reduces the memory costs and computation time while providing comparative results.

An efficient hybrid time integration approach for numerical simulations of multiscale electromagnetic problems is presented.