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The purpose of this study is to provide the full-state mathematical model and devise a nonlinear controller for a balloon-supported unmanned aerial vehicle (BUAV).

Newtonian mechanics is used to establish the nonlinear mathematical model of the proposed vehicle assembly which incorporates the dynamics of both balloon and quadrotor UAV. A controllable form of the nine degrees of freedom model is derived. Backstepping control is designed for the proposed model and simulations are performed to assess the tracking performance of the proposed control.

The results show that the proposed methodology works well for smooth trajectories in presence of wind gusts. Moreover, the final mathematical model is affine and various nonlinear control techniques can be used in the future for improved system performance.

Multi-rotor unmanned aerial vehicles (MUAVs) are equipped with controllers but are constrained by smaller flight endurance and payload carrying capability. On the contrary, lighter than air (LTA) aerial vehicles have longer flight times but have poor control performance for outdoor operations. One of the solutions to achieve better flight endurance and payload carrying capability is to augment the LTA balloon to MUAV. The novelty of this research lies in full-order mathematical modeling along with transformation to controllable form for the BUAV assembly.

The aim of this paper is to design a nonlinear disturbance observer-based control (DOBC) method obtained by patching a control method developed using a robust adaptive technique and a DO.

For designing a DOBC, initially a class of nonlinear system is considered with an external disturbance. First, a DO is designed to estimate the external disturbances. This estimate is combined with the controller to reject the disturbances and obtain the desired control objective. For designing a controller, the robust sliding mode control theory is used. Furthermore, instead of using a constant switching gain, an adaptive gain tuning criterion is designed using Lyapunov candidate function. To investigate the stability and effectiveness of the developed DOBC, stability analysis and simulation study are presented.

The major findings of this paper include the criteria of designing the robust adaptive control parameters and investigating the disturbance rejection when robust adaptive control based DOBC is developed.

In practice, the flight of quadrotor is affected by different kind of external disturbances, thus leading to the change in dynamics. Hence, it is necessary to design DOBCs based on robust adaptive controllers such that the quadrotor model adapts to the change in dynamics, as well as nullify the effect of disturbances.

Designing DOBCs based on robust control method is a common practice; however, the robust adaptive control method is rarely developed. This paper contributes in the domain of DOBC based on robust adaptive control methods such that the behavior of controller varies with the change in dynamics occurring due to external disturbances.

This paper aims to devise a robust controller for the non-linear aircraft model using output feedback control topology in the presence of uncertain aerodynamic parameters.

Feedback linearization-based state feedback (SFB) controller is considered along with a robust outer loop control which is designed using Lyapunov’s second method. A high-gain observer (HGO) in accordance with the separation principle is used to implement the output feedback (OFB) control scheme. The robustness of the controller and observer is assessed by introducing uncertain aerodynamics coefficients in the dynamic model. The proposed scheme is validated using MATLAB/SIMULINK.

The efficacy of the proposed scheme is authenticated with the simulation results which show that HGO-based OFB control achieves the SFB control performance for a small value of the high-gain parameter in the presence of uncertain aerodynamic parameters.

A HGO for the non-linear model of aircraft with uncertain parameters is a novel contribution which could be further used for the unmanned aerial vehicles autopilot, flight trajectory tracking and path following.

The purpose of this paper is to provide a comprehensive and unified presentation of recent developments in skid-steer wheeled mobile robots (SSWMR) with regard to its control, guidance and navigation for the researchers who wish to study in this field.

Most of the contemporary unmanned ground robot’s locomotion is based upon the wheels. For wheeled mobile robots (WMRs), one of the prominent and widely used driving schemes is skid steering. Because of mechanical simplicity and high maneuverability particularly in outdoor applications, SSWMR has an advantage over its counterparts. Different prospects of SSWMR have been discussed including its design, application, locomotion, control, navigation and guidance. The challenges pertaining to SSWMR have been pointed out in detail, which will seek the attention of the readers, who are interested to explore this area.

Relying on the recent literature on SSWMR, research gaps are identified that should be analyzed for the development of autonomous skid-steer wheeled robots.

An attempt to present a comprehensive review of recent advancements in the field of WMRs and providing references to the most intriguing studies.

This study aims to investigate the influence of personality characteristics (risk-aversion and self-consciousness) on skepticism toward online services information (STOSI), consumer stress and health.

A between-subjects experiment (n = 228) was designed to compare effects based on third-party organization endorsement (TPO endorsed vs nonendorsed).

Results revealed that personality characteristics positively influenced STOSI, which in turn escalated consumer stress. Furthermore, consumer stress predicted detrimental effects on consumer health (increased blood pressure and heartbeat). Regarding TPO endorsements, both the risk-aversive and self-conscious consumers showed lesser STOSI when exposed to TPO-endorsed ads compared with nonendorsed ads.

This study is one of the first to examine the effects of consumer personality on consumer health through STOSI and consumer stress. In addition, the remedial roles of TPO in coping with STOSI and consumer stress also accumulate to the novelty of this study.

Extending the elaboration likelihood model (ELM), this study investigates the impact of social media influencers (SMI) on consumer well-being (CW) as well as the influence of CW on purchase intention.

A between-subjects experiment (macro- vs mega-influencer) was conducted to assess the proposed hypotheses. A total of 190 consumers participated in the experiment, and SmartPLS 3.3 was used for multigroup analyses.

Overall, argument quality (AQ), source's credibility (SC) and influencer's kindness positively predict CW, and CW predicts purchase intention. It was also found that SC is more important when information comes from a mega-influencer, whilst kindness is essential for a macro-influencer.

The results of this study imply that CW should be an essential component of influencer marketing strategy. Marketing managers should hire credible and kind influencers who can produce quality arguments. Additionally, the selection of SMI (macro- vs mega-influencer) should be aligned with the marketing objective and type of persuasion required.

This is one of the early attempts to extend ELM by introducing influencer kindness as a peripheral cue. Moreover, the study offers novelty by examining the effects of influencer characteristics (AQ, SC and kindness) on CW and comparing these effects across macro- and mega-influencers.

藉著擴展詳儘可能性模型, 本研究擬探討網絡紅人對消費者福祉的影響, 以及消費者福祉對購買意圖的影響。

研究人員進行被試間實驗 (中網紅對大型網紅) , 以對提出的假設進行評價。190名消費者參與實驗, 研究人員使用SmartPLS 3.3 進行多群組分析。

總的來說, 論點品質、來源可信度和網紅的仁慈體貼, 均能積極預測消費者福祉, 而消費者福祉亦可預測購買意圖。研究人員亦發現, 若資訊是來自大型網紅的話, 來源可信度則更形重要, 而對中網紅來說, 仁慈體貼則是不可或缺的。

研究結果暗示, 消費者福祉應是網紅市場營銷戰略的基本要素。市場經理應僱用可靠、仁慈體貼、並能提出優質論點的網紅。而且, 網絡紅人 (中網紅對大型網紅) 的挑選, 必須與營銷目標和說服的種類互相協調。

本研究為早期的嘗試, 利用引進網絡紅人的仁慈體貼作為周邊線索, 來擴展詳儘可能性模型。另外, 本研究探討網絡紅人的特徵 (論點品質、來源可信度和仁慈體貼) 會如何影響消費者福祉; 研究人員亦跨中網紅和大型網紅, 對這些影響進行比較, 就此而言, 本研究提供了創新的研究意念。

This study aims to empirically develop a reliable and valid instrument measuring the online service quality in the context of the banking sector in India.

The methodological framework of this research comprises developing an instrument that is based on previous literature, qualitative and quantitative procedure. The study used the survey method and collected data via a well-structured questionnaire from a sample of active Internet banking users. The proposed instrument is identified by the data-reduction technique that is exploratory factor analysis (EFA), and validated through the confirmatory factor analysis (CFA).

The results confirmed that the digital banking service quality scale (DBSQual) contains 24 items in seven dimensions: (1) web architecture, (2) user friendliness, (3) efficiency of website, (4) reliability, (5) responsiveness, (6) security and (7) personalization. The relationship between digital banking service quality and e-customer satisfaction has also been found to be significant in this study.

The results of this study do not find general application for different banks operating in the same sector in India. More testing of DBSQual is required across various different contexts for validity augmentation. In addition, findings would be more reliable if the non-Indian context could be taken into consideration. Thus, such limitations open a window for future research.

This study is quite fruitful for the banking organizations in measuring their online services, and enables them to implement their marketing and operational strategies more effectively and efficiently.

The contribution of this study is the development and validation of a new instrument that is DBSQual that contains seven determinants of customers' e-service quality perception, emphasis on measuring online service quality in the Indian banking sector. These determinants will offer banks a promising starting idea for establishing an effective quality management for their online businesses. They will be able to increase the opportunities by tapping themselves at a competitive edge.

The purpose of this paper is to empirically investigate the impact of board financial expertise on the shareholding of foreign institutional investors in an emerging equity market of China and to explore whether ownership concentration moderates the relationship between board financial expertise and foreign institutional investment.

To test the hypothesized relationships, this study uses panel data regression models, i.e. static (fixed effect and random effect) and dynamic (two-step generalized methods of moments) models. Further, to control the possible endogeniety issue, this study uses two instrumental variables, namely, board size and industry average financial expertise of board to proxy board financial expertise. This study covers a period from 2006 to 2015 for 169 listed Chinese firms.

The results revealed that foreign institutional investors positively perceived board financial expertise and holds more shareholdings with the increasing level of financial experts at boards of directors. Moreover, ownership concentration positively moderated this relationship. It means that in highly concentrated firms, the board financial expertise conveys a stronger signal to foreign institutional investors that firms can manage financial resources rationally by controlling negative effects of ownership concentration. Further, the robustness model also confirmed the relationship between board financial expertise and foreign institutional shareholdings.

To the best of authors’ knowledge, this is the first study to investigate board-level financial expertise as a determinant of foreign institutional ownership. Further, no previous study has used ownership concentration as a contextual variable on the relationship between board financial expertise and foreign institutional investment.

The aim of this research is to measure the impact of eWOM (electronic word of mouth) and brand celebrity use on the purchasing behavior of sports consumers.

To test the model hypotheses, sports consumers who use social media and have purchased at least one online sports product were selected as the research group. Online survey method was used, and 836 participants were reached. The model was tested with structural equation modeling (SEM) through smart PLS software.

As a result, the quality, credibility and usefulness of the information consumers encounter on online platforms cause them to adopt information about products or services, and then exhibit online purchase behavior. While the attractiveness and trustworthiness of celebrities are seen as important factors affecting consumers' online purchase of sports products, the effect of celebrity expertise was found to be ineffective in this study.

Marketers can develop more effective eWOM strategies by considering consumers' expectations. Businesses that want to implement an effective marketing strategy may prefer celebrities in product promotions or advertisements of their brands.

This research revealed the effect of eWOM and celebrity endorsement on the online purchase behavior of sports consumers in terms of the sports industry. Unlike previous studies, this study examined these variables together on sports consumers and contributed to the development of models.

Irrigation System Management (ISM) poses many issues in terms of social and technical aspects. These can be further elaborated as the issues toward the efficiency of infrastructure, equity of water sharing, environmental integrity and economic acceptability. Water losses and the structural changes of the system caused many issues putting the irrigation system into distress. Hence, this urges the need for sustainable ISM to improve social and technical attributes in ISM. This paper aims to apply the Socio-Technical Systems (STSs) theory for sustainable ISM.

The qualitative expert opinion survey method was selected as the research strategy to approach the research aim. Sixteen industry professionals in the ISM sector were selected through the purposive sampling method to conduct semi-structured interviews to collect data in the Sri Lankan context. Code-based content analysis through a directed approach was used to analyse the data.

Four main categories of strategies were emerged from the research findings as “engineering strategies”, “operational strategies”, “management strategies” and “regulatory strategies” through STS approach for sustainable ISM. The STS framework was developed by combining engineering and operational strategies into the technical subsystem and the management and regulatory strategies into the social subsystem to approach the aim of achieving contemporary system management in irrigation in a sustainable manner.

The research revealed the links between the strategies emerged from various disciplines to minimise the issues in ISM from the perspectives of technical and social subsystems. The study contributes to knowledge by providing a framework for sustainable ISM by applying the socio-technical systems theory by integrating the concepts of sustainability.