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An anisotropic modelling of hollow porous cylinders under harmonic axial loading is proposed to simulate the in vivo behavior of structural elements of cortical bone called osteons. The peripheral surface of the medium is supposed to be impermeable, except on possible existing cracks. Numerical tests are performed by analytical and finite element methods based on the Biot poroelastic theory. The influence of microcracks on the fluid flow is numerically investigated. The findings show that the existence of peripheral cracks directly modifies the stimulation of the mechano‐sensitive network of the bone. Thus, this study attempts to propose a likely mechanism by which bone can sense changes of the surrounding mechanical environment.

This paper examines correlations of the underlying structural shocks and the degree of synchronization in the impulse responses of output, inflation and trade to a one standard deviation shock to non-oil commodities price index and exchange rates within the West African Monetary Zone (WAMZ) countries from 1990q1 to 2020q1.

This paper uses the structural vector autoregressive model to isolate the underlying structural shocks and compares them with the West African Monetary Union (WAEMU) countries.

Findings from the study suggest that correlations of underlying structural shocks are more profound in the WAEMU than in the WAMZ. Impulse responses of output to price and exchange rate shocks are more symmetric in the WAEMU than in the WAMZ. However, impulse responses of inflation to price and exchange rate shocks are symmetric in the WAMZ than in the WAEMU and responses of trade in both sub-groups are not uniform.

The paper concludes that the WAMZ does not constitute an Optimum Currency Area concerning the correlations of the structural shocks and output. However, it has achieved convergence in inflation and there are adequate adjustment mechanisms to shocks in the WAMZ than in the WAEMU. Therefore, the WAMZ may not suffer from joining the monetary union. Thus, economic Community of West African States may take steps to roll out the monetary union.

The paper examines correlations of the underlying structural shocks, impulse responses of output and inflation to shocks to commodities price and exchange rates in the WAMZ and compares them with the WAEMU.

The primary objective of this chapter is to synthesize and organize prevailing theoretical perspectives on metacognition into a framework that can enhance understanding of metacognitive phenomena, with the aim of stimulating future research in the field of organizational behavior and human resources management (OBHRM). The author starts with a review of the history of metacognition research, distinguishing it from related theoretical constructs such as cognition, executive function, and self-regulation. Following this, the author outlines five constituent elements of metacognition – metacognitive knowledge, metacognitive experiences, metacognitive monitoring, a dynamic mental model, and metacognitive control – with discussions on their interrelationships and respective functions. Two approaches to metacognition, a process approach and an individual-difference approach, are then presented, summarizing key questions and findings from each. Finally, three broad directions for future research in OBHRM are proposed: examining metacognitive processes, considering mechanisms beyond learning to explain the effects of metacognition, and exploring both domain-specific and general metacognitive knowledge and skills. The implications of these research directions for personnel and human resources management practices are discussed.

Typical feature-matching algorithms use only unary constraints on appearances to build correspondences where little structure information is used. Ignoring structure information makes them sensitive to various environmental perturbations. The purpose of this paper is to propose a novel graph-based method that aims to improve matching accuracy by fully exploiting the structure information.

Instead of viewing a frame as a simple collection of keypoints, the proposed approach organizes a frame as a graph by treating each keypoint as a vertex, where structure information is integrated in edges between vertices. Subsequently, the matching process of finding keypoint correspondence is formulated in a graph matching manner.

The authors compare it with several state-of-the-art visual simultaneous localization and mapping algorithms on three datasets. Experimental results reveal that the ORB-G algorithm provides more accurate and robust trajectories in general.

Instead of viewing a frame as a simple collection of keypoints, the proposed approach organizes a frame as a graph by treating each keypoint as a vertex, where structure information is integrated in edges between vertices. Subsequently, the matching process of finding keypoint correspondence is formulated in a graph matching manner.

The purpose of this paper is to present a localisation system for an indoor rotary‐wing micro aerial vehicle (MAV) that uses three onboard LEDs and base station mounted active vision unit.

A pair of blade mounted cyan LEDs and a tail mounted red LED are used as on‐board landmarks. A base station tracks the landmarks and estimates the pose of the MAV in real time by analysing images taken using an active vision unit. In each image, the ellipse formed by the cyan LEDs is used for 5 degree of freedom (DoF) pose estimation with yaw estimation from the red LED providing the 6th DoF.

About 1‐3.5 per cent localisation error of the MAV at various ranges, rolls and angular speeds less than 45°/s relative to the base station at known location indicates that the MAV can be accurately localised at 9‐12 Hz in an indoor environment.

Line‐of‐sight between the base station and MAV is necessary while limited accuracy is evident in yaw estimation at long distances. Additional yaw sensors and dynamic zoom are among future work.

Provided an unmanned ground vehicle (UGV) as the base station equipped with its own localisation sensor, the developed system encourages the use of autonomous indoor rotary‐wing MAVs in various robotics applications, such as urban search and rescue.

The most significant contribution of this paper is the innovative LED configuration allowing full 6 DoF pose estimation using three LEDs, one camera and no fixed infrastructure. The active vision unit enables a wide range of observable flight as the ellipse generated by the cyan LEDs is recognisable from almost any direction.

This study aims to analyze and discuss the key design assumptions needed for design of car parks in steel, to highlight the impact that the increased fire loads introduced by modern cars and changes in the fire dynamics have on the design, such as fire spread leading to non-localized fires.

In particular, a reliable fire load density to be used for structural design of car park structures is assessed, based on investigations of the fire loads of modern cars. Based on knowledge of fire load and fire performance of cars, the consequences on the fire safety design of steel structures are presented.

Design recommendation about fire load density and fire protection of common steel profiles are given. Finally, the proposed design is compared with a design practice that has been applied in many instances for car parks constructed with unprotected steel, and recommendations for a reliable design process are provided.

Numerous car park buildings have recently been designed of steel structures without passive or active fire protection. The key assumptions that makes possible such design are local fire scenarios, outdated values of the car fire load and utilization of the ultimate steel strength. This paper identifies the shortcomings of such key assumptions, indicating the need for revisiting the methods and possibly even checking the analyses carried out for some already-built car parks.

The purpose of this study aims to simulate the long-period fiber grating sensor pulse peak position against the transmission range. The long-period fiber grating sensor pulse peak position against the transmission range is simulated clearly where the pulse peak value at zero position is 0.972655 with the ripple factor of unity. It is demonstrated that the long-period fiber grating sensor bandwidth can be estimated to be 50 µm. Wavelength shift of the long-period grating sensor (LPGS) is reported against grating wavelength, applied temperatures and applied micro strain.

This work has reported the numerical simulation of LPGS transmission spectrum behavior characteristics under the strain and temperature effects by using OptiGrating simulation software. The sensor fabrication material is silica-doped germanium. The transmittivity/reflectivity and input spectrum pulse intensity of long-period Bragg sensor variations are simulated against the grating wavelength variations. Input/output pulse intensity of LPGS variations is simulated against the timespan variations with the Gaussian input pulse from 100 to 500 km link length.

Temperature variation and strain variation of the LPGS are outlined against both applied temperatures and micro-strain variations at the central grating wavelength of 1,550 nm.

It is demonstrated that the long period fiber grating sensor bandwidth can be estimated to be 50 µm. Wavelength shift of the long period grating sensor is reported against both grating wavelength, applied temperatures and applied micro strain. Temperature variation and strain variation of the long period grating sensor are outlined against both applied temperatures and micro strain variations at the central grating wavelength of 1550 nm.

The time and effort involved in indexing documents can be reduced by requiring the indexer only to underline the words he regards as significant, instead of allocating class numbers or concepts. An experimental index to scientific reports made by word‐choosing in this way compares favourably with a concept‐based index. An index derived from words chosen by information scientists is better than those derived from words chosen by authors or keypunch operators. If abstracts are available of documents recorded as a result of a search, irrelevant material can quickly be sifted out by hand, with only a slight loss of relevant material. A KWIC‐type index recovers the most relevant documents almost as well as more elaborate indexes, and several independent simple indexes may give higher recall than a single more elaborate index.

The successful application of the group of unmanned aerial vehicles (UAVs) in the tasks of monitoring large areas is becoming a promising direction in modern robotics. This paper aims to study the tasks related to the control of the UAV group while performing a common mission.

This paper discusses the main tasks solved in the process of developing an autonomous UAV group. During the survey, five key tasks of group robotics were investigated, namely, UAV group control, path planning, reconfiguration, task assignment and conflict resolution. Effective methods for solving each problem are presented, and an analysis and comparison of these methods are carried out. Several specifics of various types of UAVs are also described.

The analysis of a number of modern and effective methods showed that decentralized methods have clear advantages over centralized ones, since decentralized methods effectively perform the assigned mission regardless of on the amount of resources used. As for the method of planning the group movement of UAVs, it is worth choosing methods that combine the algorithms of global and local planning. This combination eliminates the possibility of collisions not only with static and dynamic obstacles, but also with other agents of the group.

The results of scientific research progress in the tasks of UAV group control have been summed up.