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Docking technology plays a crucial role in enabling long-duration operations of autonomous underwater vehicles (AUVs). Visual positioning solutions alone are susceptible to abnormal drift values due to the challenging underwater optical imaging environment. When an AUV approaches the docking station, the absolute positioning method fails if the AUV captures an insufficient number of tracers. This study aims to to provide a more stable absolute position visual positioning method for underwater terminal visual docking.

This paper presents a six-degree-of-freedom positioning method for AUV terminal visual docking, which uses lights and triangle codes. The authors use an extended Kalman filter to fuse the visual calculation results with inertial measurement unit data. Moreover, this paper proposes a triangle code recognition and positioning algorithm.

The authors conducted a simulation experiment to compare the underwater positioning performance of triangle codes, AprilTag and Aruco. The results demonstrate that the implemented triangular code reduces the running time by over 70% compared to the other two codes, and also exhibits a longer recognition distance in turbid environments. Subsequent experiments were carried out in Qingjiang Lake, Hubei Province, China, which further confirmed the effectiveness of the proposed positioning algorithm.

This fusion approach effectively mitigates abnormal drift errors stemming from visual positioning and cumulative errors resulting from inertial navigation. The authors also propose a triangle code recognition and positioning algorithm as a supplementary approach to overcome the limitations of tracer light positioning beacons.

The author proposed a friction plunge micro-welding (FPMW) method and applied it to column grid array packaging to realize the connection of copper columns without precision molds assisted positioning. The purpose of this paper is to study the flow behavior of the solder undergoing frictional thermo-mechanical action during the FPMW and to determine the source of the solders in the micro-zones with different microstructure characteristics near the solder/Cu column friction interface.

Three kinds of Sn58Bi/SAC305 and SAC305/Pb90Sn composite solder samples were designed to study the flow behavior of the solder during FPMW using Bi and Pb as tracer elements.

The results show that most of the solders in the position occupied by the copper column was softened and plasticized during the welding process and was extruded to side of the copper column, flowing axially, circumferentially and radially along a trajectory similar to a conical spiral line. Under the drive of the tangential friction force and the radial hold-tight force, the extruded out visco-plastic solders fully mixed with the visco-plastic solders on the sides of the copper column, and bonded with the solders that deformed plastically on the periphery, so that a stir zone and a dynamic recrystallization zone finally evolved. The outside plastically deformed solders evolved into a thermo-mechanical affected zone.

The flow behavior of the solder during the FPMW was determined, as well as the source of the solders in micro-zones with different microstructure characteristics.

The COVID-19 pandemic has affected around 216 countries and territories worldwide and more than 2000 cities in India, alone. The smart cities mission (SCM) in India started in 2015 and 100 smart cities were selected to be initiated with a total project cost of INR 2031.72 billion. Smart city strategies play an important role in implementing the measures adopted by the government such as the issuance of social distancing regulations and other COVID-19 mitigation strategies. However, there is no research reported on the role of smart cities strategies in managing the COVID-19 outbreak in developing countries.

This paper aims to address the research gap in smart cities, technology and healthcare management through a review of the literature and primary data collected using semi-structured interviews.

Each city is unique and has different challenges, the study revealed six key findings on how smart cities in India managed the COVID-19 outbreak. They used: Integrated Command and Control Centres, Artificial Intelligence and Innovative Application-based Solutions, Smart Waste Management Solutions, Smart Healthcare Management, Smart Data Management and Smart Surveillance.

This paper contributes to informing policymakers of key lessons learnt from the management of COVID-19 in developing countries like India from a smart cities’ perspective. This paper draws on the six Cs for the implications directed to leaders and decision-makers to rethink and act on COVID-19. The six Cs are: Crisis management leadership, Credible communication, Collaboration, Creative governance, Capturing knowledge and Capacity building.

Climate-induced damage is a pressing problem for the preservation of cultural properties. Their physical deterioration is often the cumulative effect of different environmental hazards of variable intensity. Among these, fluctuations of temperature and relative humidity may cause nonrecoverable physical changes in building envelopes and artifacts made of hygroscopic materials, such as wood. Microclimatic fluctuations may be caused by several factors, including the presence of many visitors within the historical building. Within this framework, the current work is focused on detecting events taking place in two Norwegian stave churches, by identifying the fluctuations in temperature and relative humidity caused by the presence of people attending the public events.

The identification of such fluctuations and, so, of the presence of people within the churches has been carried out through three different methods. The first is an unsupervised clustering algorithm here termed “density peak,” the second is a supervised deep learning model based on a standard convolutional neural network (CNN) and the third is a novel ad hoc engineering feature approach “unexpected mixing ratio (UMR) peak.”

While the first two methods may have some instabilities (in terms of precision, recall and normal mutual information [NMI]), the last one shows a promising performance in the detection of microclimatic fluctuations induced by the presence of visitors.

The novelty of this work stands in using both well-established and in-house ad hoc machine learning algorithms in the field of heritage science, proving that these smart approaches could be of extreme usefulness and could lead to quick data analyses, if used properly.

The advancement of a profession depends on factors such as firm education, training programmes and vibrant professional associations. The purpose of this study is to provide baseline information on archives and records management (ARM) professionals from Africa, including their views on education and training programmes. Related studies have been limited to investigating the experiences of graduates from a few institutions within a limited jurisdiction. Similar studies have not been conducted by African-based ARM associations.

This study’s survey approach was administered electronically. Two surveys explored themes through 10 research questions in three categories: background information; characteristics of the education; and types of courses and extent covered during the study.

The two surveys had 107 and 179 respondents, respectively, domiciled in 19 African countries. In both studies, about 75% of the respondents had an undergraduate- or master-level qualification. Between 69% and 87% of the respondents from the first and second surveys, respectively, had completed their educational programmes within their home countries. There was varied sentiment on the types of courses and level of coverage within their studies. Legal and technology aspects were less covered in the curriculum than core subjects.

To the best of the author’s knowledge, this study is the first with findings from ARM respondents across several African countries. It provides insight into the demographics and educational programmes. This study’s unique contribution provides baseline data for more detailed and nuanced studies that will explore data and investigate patterns within and among individual countries on the continent.

The purpose of this paper is to solve the problem that mobile robots are still based on reactive collision avoidance in unknown dynamic environments leading to a lack of interaction with obstacles and limiting the comprehensive performance of mobile robots. A dynamic window approach with multiple interaction strategies (DWA-MIS) is proposed to solve this problem.

The algorithm firstly classifies the moving obstacle movement intention, based on which a rule function is designed to incorporate positive incentives to motivate the robot to make correct avoidance actions. Then, the evaluation mechanism is improved by considering the time cost and future information of the environment to increase the motion states. Finally, the optimal objective function is designed based on genetic algorithm to adapt to different environments with time-varying multiparameter optimization.

Faced with obstacles in different states, the mobile robot can choose a suitable interaction strategy, which solves the limitations of the original DWA evaluation function and avoids the defects of reactive collision avoidance. Simulation results show that the algorithm can efficiently adapt to unknown dynamic environments, has less path length and iterations and has a high comprehensive performance.

A DWA-MIS is proposed, which increases the interaction capability between mobile robots and obstacles by improving the evaluation function mechanism and broadens the navigation strategy of DWA at a lower computational cost. After real machine verification, the algorithm has a high comprehensive performance based on real environment and provides a new idea for local path planning methods.

This study proposes and validates an integrated theoretical model involving the theory of planned behavior (TPB), health belief model (HBM), personal norms and information privacy to understand determinants of acceptance and resistance to the use of mobile contact tracing app (MCTA) in a pandemic situation.

This study draws on online surveys of 194 research respondents and uses partial least squares structural equation modeling (PL-SEM) to test the proposed theoretical model.

The study establishes that a positive attitude towards MCTA is the most important predictor of individuals' willingness to use MCTA and resistance to use MCTA. Furthermore, barriers to taking action positively influence resistance to the use of MCTA. Personal norms negatively influence resistance to the use of MCTA. Information privacy showed a negative and positive influence on willingness to use MCTA and use the resistance of MCTA, respectively, but neither was statistically significant. The authors found no significant influence of perceived vulnerability, severity, subjective norms and perceived behavioral control on either acceptance or use resistance of MCTA.

The study has been one of the first in the literature to propose an integrated theoretical model in the investigation of the determinants of acceptance and resistance to the use of MCTA in a single study, thereby increasing the scientific understanding of the factors that can facilitate or inhibit individuals from engaging in the use of a protection technology during a pandemic situation.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-10-2021-0533

This paper aims to help higher education institutions (HEIs) develop a better understanding of student support and services needs, thereby enabling them to allocate limited resources for initiatives that effectively improve student experience.

An assessment framework following the Kano analysis is developed to categorize student service features based on customer satisfaction and need fulfillment. The framework is used at a local university, using 23 service features listed as minimum requirements by the national regulatory body for education. Analysis of the satisfaction survey results and prioritization are based on quality indices derived from a factor of importance and the satisfaction gap. A survey was conducted for two academic years to generate a comparison of results.

Of the list mandated as minimum requirements for HEIs, the study revealed that no features were regarded as “must-be,” eight as performing, 14 as attractive and one as indifferent by the students. As these results were disaggregated per year level, the natural decay of delight as in the Kano theory was exhibited as there were less attractive features for students who have been in the university longest. After a full-year academic cycle, results compared to the baseline figures seemed to reveal of impact of the achievement of performance targets by the units rendering specific activities on client satisfaction.

Further rounds of the study are needed to build up more data sets on the relationship between objective performance and satisfaction level for performing features, mindful that this categorization is also bound to change along the way.

As HEIs in the Philippines journey towards the establishment of their own respective internal quality assurance systems, this study provides a practical approach for institutions to transform a mere list of student services for compliance into a strategic tool to enhance the student experience.

In the context of continuous quality improvement, the study presents how the qualitative Kano model, along with simple quantitative tools in the methodology, can be utilized not only in the planning stage of service design but also in closing the planning, doing, checking and acting (PDCA) cycle and opening the quality improvement spiral.

Purpose: This chapter investigates the current skill gap in small-scale industries, the need for skill development and digital training in micro, small, and medium enterprises (MSME), and reviews policies for skill development and solutions.

Need for the Study: While the legislature and organisations have initiated various considerations for the successful implementation of the Skill Development System in the country’s MSMEs, there are significant challenges that must be addressed quickly to fill the skill gap in workers in this digital era.

Research Methodology: Secondary data has been used for the chapter review. Analysis has been done based on review data from women handloom and handicraft workers in the micro or craft industry who received a Star rating from the National Skill Development Corporation (NSDC) partners in Lucknow. For data collection, a questionnaire based on random sampling was used. The data were analysed using a rudimentary weighted average and a percentage technique.

Findings: The studies provide answers to some fundamental problems: are small industry employees indeed mobilised to be skilled outside the official schooling system? Is the training delivery mechanism adequate to prepare pupils for employment? Would industries be willing to reduce minimum qualification criteria to foster skill development?

Practical Implication: Non-technical aptitudes digital and soft skills for workers in this sector should be emphasised in MSMEs, and significant reforms in MSME sectors and capacity-building education and training programmes should be implemented in the Indian industry to generate small and medium enterprises production and employment.

Aero-engine exhaust plume length can be more than the aircraft length, making it easier to detect and track by infrared seeker. Aim of this study is to analyze the effect of free stream Mach number (M_∞) on length of potential core of plume. Also, change in infrared (IR) signature of plume and aircraft surface with variation in elevation angle (θ) is examined.

Convergent divergent (CD) nozzle is located outside the rear fuselage of the aircraft. A two dimensional axisymmetric computational fluid dynamics (CFD) study was carried out to study effect of M_∞ on potential core. The CFD data with aircraft and plume was then used for IR signature analysis. The sensor position is changed with respect to aircraft from directly bottom towards frontal section of aircraft. The IR signature is studied in mid wave IR (MWIR) and long wave IR (LWIR) band.

The potential plume core length and width increases as M_∞ increases. At higher altitudes, the potential core length increases for a fixed M_∞. The plume emits radiation in the MWIR band, whereas the aerodynamically heated aircraft surface emits IR in the LWIR band. The IR signature in the MWIR band continuously decreases as the sensor position changes from directly bottom towards frontal. In the LWIR band the IR signature initially decreases as the sensor moves from the directly bottom to the frontal, as the sensor begins to see the wing leading edges and nose cone, the IR signature in the LWIR band slightly increases.

The novelty of this study comes from the data reported on the effect of free stream Mach number on the potential plume core and variation of the overall IR signature of aircraft with change in elevation angle from directly below towards frontal section of aircraft.