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This paper aims to propose output feedback-based control algorithms for the flight control system of a scaled, un-crewed helicopter in its hover flight mode.

The proposed control schemes are based on H_∞ control and composite nonlinear control. The gains of the output feedback controllers are obtained as the solution of a set of linear matrix inequalities (LMIs).

In the proposed schemes, the finite-time convergence of system states to trim condition is achieved with minimum deviation from the steady-state. As the proposed composite nonlinear output feedback design improves the transient response, it is well suited for a scaled helicopter flight. The use of measured output vector instead of the state vector or its estimate for feedback provides a simple control structure and eliminates the need for an observer in real-time application. The proposed control strategies are relevant to situations in which a simple controller is essential due to economic factors, reliability and hardware implementation constraints.

The proposed control strategies are relevant to situations in which a simple controller is essential due to economic factors, reliability and hardware implementation constraints. They also have significance in applications where the number of measurement quantities needs to be minimized such as in a fully functional rotor-craft unmanned aerial vehicle.

The developed output feedback control algorithms can be used in small-scale helicopters for numerous civilian and military applications.

This work addresses the LMI-based formulation and solution of an output feedback controller for a hovering un-crewed helicopter. The stability and robustness of the closed-loop system are proved mathematically and the performance of the proposed schemes is compared with an existing strategy via simulation studies.

Hate speech is an expression of intense hatred. Twitter has become a popular analytical tool for the prediction and monitoring of abusive behaviors. Hate speech detection with social media data has witnessed special research attention in recent studies, hence, the need to design a generic metadata architecture and efficient feature extraction technique to enhance hate speech detection.

This study proposes a hybrid embeddings enhanced with a topic inference method and an improved cuckoo search neural network for hate speech detection in Twitter data. The proposed method uses a hybrid embeddings technique that includes Term Frequency-Inverse Document Frequency (TF-IDF) for word-level feature extraction and Long Short Term Memory (LSTM) which is a variant of recurrent neural networks architecture for sentence-level feature extraction. The extracted features from the hybrid embeddings then serve as input into the improved cuckoo search neural network for the prediction of a tweet as hate speech, offensive language or neither.

The proposed method showed better results when tested on the collected Twitter datasets compared to other related methods. In order to validate the performances of the proposed method, t-test and post hoc multiple comparisons were used to compare the significance and means of the proposed method with other related methods for hate speech detection. Furthermore, Paired Sample t-Test was also conducted to validate the performances of the proposed method with other related methods.

Finally, the evaluation results showed that the proposed method outperforms other related methods with mean F1-score of 91.3.

The main novelty of this study is the use of an automatic topic spotting measure based on naïve Bayes model to improve features representation.

Given food industry manufacturers and retailers' growing economic interest in sub-Saharan Africa (SSA), this research aims to contribute to the understanding of consumer food decisions in this specific geographical area. Thus, the intention is to analyze whether there are significant differences in the appreciation of food values according to certain key demographics of consumers (related to the individual and the context) in one of the largest SSA economies: Nigeria.

The review of the relevant literature enabled us to propose a series of hypotheses regarding potential significant differences in the appreciation of a series of food values (in particular, price, safety, environmental impact, nutrition and weight and measures) according to variables related to the individual and the economic and social context. In order to test the hypotheses, a structured questionnaire was personally administered to 500 Lagos residents between June and July 2020. The questionnaire contained, as well as diverse questions related to the appreciation of food values selected for this study, a group of questions about the consumers' sociodemographic characteristics – at both the individual and context level. The database was analyzed using descriptive statistics and Kruskal–Wallis tests.

The results show that nutrition and weight and measurement values are the most and least appreciated food values, respectively. However, these values differ across segments determined by the chosen sociodemographic variables.

The results of this study are preliminary and not a complete representation of the Lagos State population, and, consequently, of the Nigerian population. Additional studies in the same and other countries in SSA are needed to confirm the authors’ findings. The results, however, provide an insight into what the most likely outcomes are. A field survey was used as respondents tend not to answer online surveys spontaneously.

Food manufacturers and retailers should encourage consumer-operator feedback mechanisms to improve product characteristics and development. The variations found across each segment can be capitalized upon for advertising and branding food products.

Having selected a country in SSA for the study is an important contribution, given that few studies have focused on this geographical area.

The possible effect of conflicts as the consequence of differences between personal and organizational values (OV) on organizational commitment (OC) of internal construction stakeholders was an unclear issue in the areas of organizational behaviour in the construction industry, especially in Malaysia. Therefore, the purpose of this paper is to focus on this issue in the Malaysian construction industry.

This paper targeted professional project consultants, who are identified as architects, engineers, and quantity surveyors, as the internal construction stakeholders. The personal-OV and the level of OC of the stakeholders were evaluated through a questionnaire survey. To achieve the research objective, comparative and hierarchical regression analyses were performed.

The results generated by the analyses indicated a high level of value conflicts in the construction organizations which significantly and negatively affected commitment of the internal stakeholders.

Value conflicts in construction organizations are the agenda of this paper while not many empirical studies have been conducted on this issue in Malaysia. This paper through investigating the potential effect of value conflicts on the stakeholders’ commitment reveals the importance of interaction between personal and OV in construction organizations which contributes to the extant literature of organizational behaviour as to the construction literature.

This semi‐annotated bibliography (with a focus on feminist activist work) is a project I continually revise. Therefore, please view it as incomplete. If you have any additions, please write to me at: General College, 280 Appleby Hall, University of Minnesota, Minneapolis, MN 55455. I've put an asterisk next to materials I've found most useful and have separated the bibliography into two sections: regular or irregular periodicals that focus on the Israeli/Palestinian conflict and books that address the conflict.

Guided by feminist perspectives, we critique existing approaches to the study of womenʼs entrepreneurship on epistemological grounds and suggest that the entrepreneurship field needs to recognize gendered assumptions in theorizing. Deploying a feminist framework, we suggest that understanding the “gender gap” in entrepreneurship requires focus on institutional and structural barriers women entrepreneurs face. Existing studies of women entrepreneurs often compare women with men without considering how gender and gender relations impact the very concepts and ideas of entrepreneurship. We propose, therefore, a conceptualization of entrepreneurship that illuminates gender bias and calls attention to the interrelated individual, institutional, and structural barriers in the entrepreneurial process that arrive out of societal and cultural gender norms. Through praxis or engaged practice, we redirect scholarship in the entrepreneurship field, while proposing ways that can promote gender equality in entrepreneurial activities. In all, our gender integrative conceptualization of entrepreneurship contributes to the entrepreneurship field by recognizing and addressing a more expansive realm of influential factors within the entrepreneurial ecosystem that have previously been researched separately.

Addresses three separate initiatives: South Yorkshire Further Education Consortium (SYFEC); e‐skills4industry – a partnership between Lewisham College and Deloitte; and Cascade and information and communication technology (ICT) training for schools. The initiatives, however, share two important characteristics. First, they are all initiatives which have been recognised within the National Training Awards (NTA) programme organised by UK Skills and supported by the UK Government's Department for Education and Skills (DfES). Second, each of the initiatives, albeit in different ways, looks at the utilisation of information and communication technology (ICT) in different aspects of education and training. The three winning accounts featured here offer useful insight into how the further and higher education sectors, in partnership with industry, are responding to some of the challenges and opportunities that have arisen as the use of information technology (IT) becomes common place in people's working (and learning) lives.

Inequality of opportunity is revealed by measures of a gender gap in education whereby women's participation is less than men's, is of shorter duration and is concentrated on lower levels of the educational pyramid. The gap is more pronounced and demonstrable in lower income regions or developing countries but, to the extent that there are discrepancies in men's and women's educational experiences in more developed countries also, the same principles apply.

The largest share of a building maintenance budget goes towards preventing or repairing building defects. Also, building defects shorten a building’s lifetime, impact the user’s safety and health, prevent the buildings from performing their functions well and repairing building defects generates waste. Therefore, this study aims to specify the factors that affecting the number of building defects and how to reduce their negative impacts.

A case study was used as a research strategy and convergent parallel mixed methods were used as research design. Quantitative and qualitative data were collected concurrently, followed by independent analyses of the quantitative and qualitative data, and then merged the two sets of results according to the procedure of using the convergent parallel design. Descriptive statistics analysed quantitative data, whilst qualitative data was analysed by the content analysis technique.

The findings of this study explored the factors that affect the number of defects in buildings, the significant factors were related to the building’s life cycle in terms of design, construction, operation and maintenance phase; relevant attributes were construction teams, building users and maintenance teams. The study also addressed the approaches to minimise the negative impacts of those factors. Their negative impacts mainly contributed to increased building defects that increase maintenance costs, affect users’ safety and health, reduce buildings’ lifespan and cause environmental impact due to resource extraction.

The existing studies have not adequately addressed the significant factors that affect the number of building defects. Also, emerging technologies and environmental sustainability considerations related to building defects have not been linked in previous related work. Therefore, the present study has contributed to filling this gap.