A survey of parameterized algorithms and the complexity of edge modification

The survey is a comprehensive overview of the developing area of parameterized algorithms for graph modification problems. It describes state of the art in kernelization, subexponential algorithms, and parameterized complexity of graph modification. The main focus is on edge modification problems, where the task is to change some adjacencies in a graph to satisfy some required properties. To facilitate further research, we list many open problems in the area.publishedVersio

Identifying users using Keystroke Dynamics and contextual information

Biometric identification systems based on Keystroke Dynamics have been around for almost forty years now. There has always been a lot of interest in identifying individuals using their physiological or behavioral traits. Keystroke Dynamics focuses on the particular way a person types on a keyboard. The objective of the proposed research is to determine how well the identity of users can be established when using this biometric trait and when contextual information is also taken into account. The proposed research focuses on free text. Users were never told what to type, how or when. This particular field of Keystroke Dynamics has not been as thoroughly studied as the fixed text alternative where a plethora of methods have been tried. The proposed methods focus on the hypothesis that the position of a particular letter, or combination of letters, in a word is of high importance. Other studies have not taken into account if these letter combinations had occurred at the beginning, the middle, or the end of a word. A template of the user will be built using the context of the written words and the latency between successive keystrokes. Other features, like word length, minimum number of needed words to consider a session valid, frequency of words, model building parameters, as well as age group and gender have also been studied to determine those that better help ascertain the identity of an individual. The results of the proposed research should help determine if using Keystroke Dynamics and the proposed methodology are enough to identify users from the content they type with a good enough level of certainty. From this moment, it could be used as a method to ensure that a user is not supplanted, in authentication schemes, or even to help determine the authorship of different parts of a document written by more than one user.Els sistemes d’identificació biomètrica basades en la cadència de tecleig fa gairebé quaranta anys que s’estudien. Hi ha hagut molt interès en identificar les persones a partir de les seves característiques fisiològiques o de comportament. La cadència de tecleig és la manera en la que una persona escriu en un teclat. L’objectiu de la recerca proposada és determinar com de bé es pot arribar a identificar un individu mitjançant aquesta característica biomètrica i quan també es prenen en consideració dades contextuals. Aquesta recerca es basa en text lliure. Als usuaris mai se’ls va dir què, quan o com havien d’escriure. Aquest camp de la cadència de tecleig no ha estat tan estudiat com l’alternativa de text fix on un gran ventall de mètodes s’han provat. Els mètodes d’identificació proposats es basen en la hipòtesi que la posició d’una lletra, o combinació de lletres teclejades, en una paraula és de gran importància. Altres estudis no prenen en consideració aquesta informació, és a dir, si la combinació de lletres s’ha produït al principi, al mig o al final de la paraula. Es crearà una empremta de l’usuari tenint en compte el context de les lletres en les paraules escrites i les latències entre pulsacions successives. Altres característiques com la mida de les paraules, el nombre mínim de paraules necessari per considerar una sessió vàlida, la freqüència de mots, els paràmetres de construcció dels models, així com el grup d’edat i el gènere també s’han estudiat per determinar quines són les que millor ajuden a identificar un individu. Els resultats de la recerca proposada haurien de permetre determinar si l’ús de la cadència de tecleig i els mètodes proposats són suficients per identificar els usuaris a partir del contingut que generen, sempre amb un cert marge d’error. En cas afirmatiu es podria introduir la tècnica proposada com un mètode més per assegurar que un usuari no és suplantat, en sistemes d’autenticació, o fins i tot per ajudar a determinar l’autoria de diferents parts d’un document que ha estat escrit per més d’un usuari

Strategic frameworks for managing lean construction on megaprojects; towards global integrated delivery and corporate governance

Built environment encounters substantial risk and challenges in its evolution towards sustainable development. International businesses and multinational engineering organisations face global connectivity challenges between business units, especially during the outbreak of novel coronavirus pandemic (COVID-19), which has profoundly disrupted the construction industry throughout the world. That raises the need to manage global connectivity as a main strategic goal of multinational organisations. Therefore, the research aim is to develop strategic frameworks for managing risk, challenges, and integration of lean construction (LC) and integrated project delivery (IPD) on construction megaprojects (CMPs) towards the global integrated delivery (GID) transformative initiatives and corporate governance in multinational organisations. The scope of the study mainly focuses on CMPs and multinational architecture, engineering and construction (AEC) organisations. The following research objectives (ROs) was set out in fulfilling the study’s aim: (1) To appraise influence of partnering agreements associated with BIM adoption on stakeholder’s behaviour. (2) To critically assess critical success factors (CSFs) for adoption BIM and LC practices. (3) To critically assess barriers to integrating BIM and LC practices. (4) To critically analyse and develop frameworks for the interactions between BIM and LC. (5) To critically appraise barriers to integrating LC and IPD towards the GID global initiatives. (6) To develop a competency framework that integrate LC and IPD, and critically appraise key drivers (KDs) to integrating LC and IPD towards FOW global initiatives. (7) To develop frameworks for managing risk and challenges of integrating LC and IPD towards the GID transformative initiatives and corporate governance. Research objectives were achieved via adoption of ‘mixed research methods’ involving a two-stage quantitative and qualitative research approach. This included the adoption of an in-depth review of extant literature, pilot studies, Delphi surveys, questionnaires surveys, semi-structured interviews and focus group techniques, and the use of several statistical analysis tools such as descriptive and inferential statistics and structural equation modelling (SEM). The qualitative research methodology consists of a literature review to assess challenges to integrate LeanIPD&GID on CMPs. In addition, there is an assessment of conceptualisation of LeanIPD&GID and GID strategy placements, development of LeanIPD&GID integration framework, and future of work (FOW) global initiatives with multiple validations. The thesis is presented in manuscript format. The analysis involved semi-structured interviews and focus group techniques. Stage two consisted of questionnaire survey that shaped the foundation of analysis and findings of 190 respondents from 23 countries with an extensive cosmopolitan experience of megaprojects in construction. The survey examined a set of 20 challenges to integrate LeanIPD&GID on CMPs resulting from a detailed analysis of extant literature after validation. Descriptive and inferential statistical tests were exploited for data analysis and percentage score analysis. The research findings involved conceptualisation of LeanIPD&GID principles, proposed GID strategy placements, frameworks for managing challenges of LeanIPD&GID transformative initiatives and corporate governance, FOW global initiatives and key performance indicators (KPIs). It concluded that the most significant challenges to integrate of LeanIPD&GID on CMPs are ‘lack of governmental incentives, policies, regulations or legal frameworks,’ ‘lack of client’s awareness and IPD experience amongst key stakeholders,’ ‘lack of organisation’s senior-management and client’s commitment to IPD approaches,’ ‘resistance of industry to change from traditional procurement to IPD,’ and ‘lack of integrated synergies between LC, IPD working towards LeanIPD&GID.’ Awareness of building BIM in the MENA region is higher than LC, and LC awareness is higher than IPD knowledge. While BIM adoption in the MENA region is higher than LC, LC is still taking its first steps, and IPD has little implementation. LeanBIM is slightly integrated, while LeanIPD integration is almost not present. The research findings, conclusions and recommendations provide proposed frameworks for implementation, KPIs, and GID strategy placements for LeanIPD&GID transformative initiatives and corporate governance to integrate LeanIPD&GID on CMPs and FOW global initiatives. This will allow project key stakeholders to place emphasis on managing LeanIPD&GID challenges identified in this research and commence GID strategies. The study has provided effective practical strategies for enhancing integration of LeanIPD&GID transformative initiatives on CMPs and corporate governance

Culture, People and Technology: The Driving Forces for Tourism Cities Proceedings of 8th ITSA Biennial Conference 2020

This is the proceedings of the 8th Biennial Conference of the International Tourism Studies Association, held in Jakarta and Singapore, 2nd December 202

Proceedings of 8th ITSA Biennial Conference 2020

Over the past few decades, hotel guests’ service expectations grew from services such as check-in and check-out (Cobanoglu, Corbaci, Moreo & Ekinci, 2003) to expecting hotels to, amongst others, provide services relating to tourist attractions (Adler & Gordon, 2013; Yeh, Leong, Blecher & Hu, 2005). Despite these developments, South Africa (SA) is amongst the countries confronted by the minimal utilisation of tourist attractions (National Department of Tourism, 2012) and the tourists’ lack of awareness of tourist attractions within major destinations, such as Cape Town (City of Cape Town, 2013) and Durban (eThekwini Municipality, 2014). By providing tourists with services relating to tourist attractions, hotels are likely to contribute towards addressing the minimal utilisation and lack of awareness of tourist attractions. Guest orientation (Lee, 2014), self-efficacy (Jaiswal & Dhar, 2015), motivation (Hon & Leung, 2011) and effort (Marić, Marinković, Marić & Dimitrovski, 2016) are constructs that impact on the service performance of hotel staff. However, studies have not been conducted to determine the impact of these constructs on the performance of hotel staff relating to tourist attractions. This paper forms part of a PhD study in progress which explores the constructs (Guest orientation, Self-efficacy, Motivation and Effort) that impact on hotel staff’s performance of services relating to tourist attractions. The PhD adopted a qual-QUANT research method to, in phase 1, qualitatively identify emerging themes from each construct, which will be quantitatively investigated in phase 2. This paper stems from phase 1 and aims to identify via qualitative research the key themes that emerge in each of the four constructs that are associated with hotel staff’s performance of services relating to tourist attractions. Semi-structured interviews were conducted with four certified hotel concierges belonging to Les Clefs d’ Or in SA. Thematic coding was used to identify the themes emerging from the qualitative data. Eight themes emerged from Guest orientation, five from Self-efficacy, seven from Motivation and ten from Effort