The purpose of this research was to determine what type of correlations existed between student and parent attitudes towards using smartphones in school and the resulting impact on achievement, specifically for low-achieving students. Participants in the study were third-grade students and their parents from a primary school in Singapore. The study employed a quantitative analysis to understand the correlations among the different participant groups. The instruments used were Likert-based surveys, along with scores from mid-year and end-of-year achievement exams in English and science. The three most relevant major findings showed that (a) low-achieving students show a positive attitude toward completing science activities, which correlates with an increase in science achievement; (b) the parents of low-achieving students appear to provide their children with autonomy in using their smartphones, which correlates with an increase in science achievement; and (c) having a smartphone and using the smartphone to complete school work is important to low-achieving students and their parents.

ABSTRACT This thesis conducts profile analysis on the mobile application security using peer-review articles that were published from 2010 to 2018. From the analysis, we will identify prolific authors, intuitions, and geographic regions as well as the topics addressed by the articles. The profile analysis will reveal most frequently used research methods, research approaches (quantitative, qualitative and mixed), and theories used to study the field. This thesis reveals that none of the researchers have made significant contributions to the field, and researches are not collaborating to solve their research problems. The profile analysis shows that surveys and experiments are the most utilized research methods, and most researchers studied the field at a higher level, i.e., security was the focus of the research but did not go deeper into various aspects of security such as privacy, security vulnerabilities, and mobile application security best practices.

書是社會文明的載體，是人類進步的階梯。電腦、網路的飛速發展，使得電子書引發了新一輪的書籍革命。隨著智慧型手機的出現，用手機閱讀電子書以前方便靈活，充分利用零散時間，因此受到年輕人的追捧。但是，電子書本身也存在各樣的問題，諸如不符合人們的閱讀習慣，以及產業鏈的不成熟等。因此，調查使用者的行為模式和對於電子書的喜好，以瞭解使用者對電子書的看法及接受度是本文研究的重點，本研究透過UTAUT模式探討績效期望、付出期望、社會影響、輔助條件等自變數對於使用意圖與使用行為的影響力和預測力。本研究採取問卷調查的方式，在多個網路論壇上發放，共收回問卷352份，其中剔除無效問卷後得到有效樣本計232份，有效的樣本回收率達65.9%。究結果顯示，受試者大多擁有智慧型手機（77%），使用時多以娛樂為目的（55%），僅以工作為目的者最少（4%），大多偶爾閱讀（47%），多數人未曾花錢下載付費電子書（86%）。在電子書使用經驗方面，多數受試者使用電子書不到1年（42%），在使用智慧型手機方面，同樣是使用不到1年時間者居多（60%），而使用智慧型手機閱讀電子書方面，同樣是不足1年最多（68%）。 受試者使用智慧型手機閱讀電子書之績效期望、輔助條件、付出期望等各構面對使用意圖及使用行為的預測達到顯著水準，而社會影響構面與使用經驗干擾變數則影響力未達顯著。 / Books are the vehicle for social civilization and the ladder of human progress. Due to the rapid development of computers and the Internet, electronic books (ebooks) have triggered a new round of the book revolution. With the emergence of smartphones, using mobile phones to read ebooks has become convenient, flexible, and a way to make full use of scattered bits of time. Therefore, the use of smartphones for such purposes has been pursued by young people. However, ebooks present various problems of their own, such as incompatibility with individual reading habits and the immaturity of the industrial chain. Thus, the focus of this study was to survey user behavioral models and affinity for ebooks to understand users views on and degree of acceptance of ebooks. This study used the Unified Theory of Acceptance and Use of Technology (UTAUT) to investigate the influence and predictive power of the following independent variables on usage intention and usage behavior: performance expectancy, effort expectancy, social influence, and facilitating conditions. Research results showed that a majority of respondents had smartphones (77 %). Respondents who used their phones mostly for entertainment purposes composed the largest category (55 %), while those who used their phones only for work purposes formed the smallest category (4 %). A large percentage occasionally read ebooks (47 %), but most respondents had never spent money on downloading payable ebooks (86 %). Regarding experience using ebooks, most respondents had used ebooks for under one year (42 %). Regarding experience using smart phones, the group that had used smart phones for less than one year was also the largest (60 %); a high percentage of users (68 %) had been using smart phones to read ebooks for less than one year. The predictive power of performance expectancy, facilitating conditions and effort expectancy on usage intention and usage behavior with regard to using smartphones to read ebooks achieved a level of significance. As for social influence and moderator experience, the predictive power didn’t reach a level of significance.

Syfte: Syftet med den här uppsatsen är att öka förståelsen för hur samhällets och teknikens senaste utveckling har bidragit med nya marknadsföringskanaler och vad detta innebär för företags marknadsföringsstrategier. Med detta syfte som utgångspunkt har tre forskningsfrågor formulerats för att avgränsa forskningen än mer: Hur kan smartphones som marknadsföringskanal hjälpa företag att precisera sin marknadsföring till kunden? På vilket sätt har den nya mobila tekniken, i form av smartphones, påverkat företags segmenteringsmöjligheter? Hur kan ett företag använda sig av smartphones, som ett verktyg för att hantera kundrelationer? Metod: Uppsatsen är resultatet av en kvalitativ studie med en huvudsaklig induktiv inriktning. Primärdatainsamlingen har skett genom kvalitativa semistrukturerade intervjuer. Slutsats: Efter att ha undersökt detta ämne har vi dragit slutsatsen att valet av smartphones som kanal kan hjälpa företag att precisera sin marknadsföring genom att telefonen är tillgänglig och personlig för kunden. Därför menar vi att kunders integritet och acceptans kommer att vara avgörande faktorer och viktiga att beakta. Timing är en väsentlig del av precisionsmarknadsföringen och vi har därför presenterat två nya begrepp; företagsstyrd timing och kundstyrd timing. Smartphones har även bidragit med nya möjligheter för företag att segmentera marknaden där vi framhållit slutsatsen att plats och kontext torde vara nya segmenteringsvariabler för företag att beakta. Vår slutsats är även att smartphones är en fördelaktig kanal när det kommer till byggande och hantering av kundrelationer och vi har sett tendenser till att kunden umgås med varumärket på ett sätt som tidigare inte varit möjligt. Vi introducerar ett nytt begrepp, interaktionsintensiva kommunikationsenheter, där smartphones ses som den ledande enhetstypen idag. Nyckelord: Mobilmarknadsföring, smartphones, precisionsmarknadsföring, kundstyrd timing[1], segmentering, kontext, relevans, integritet, kundrelationer, interaktionsintensiva kommunikationsenheter[2] [1]Begreppet är av oss introducerat och utgör en del av en egengjord modell. Se s 58, kapitel 5.1.1 [2]Vi har valt att introducera detta begrepp som ett samlingsnamn för en ny typ av marknadsföringskanal. Se s. 63, kapitel 5.1.3 / Purpose: The purpose of this study is to gain understanding of how the development of the society, as well as the technology, has increased the numbers of marketing channels and how they affect companies’ marketing strategies. In order to investigate this subject we have formulated three main questions: How can smartphones as a marketing channel help companies pinpoint their communication to the customer? How do smartphones affect companies' ability to segment the market? How can a company use smartphones, as a tool to manage customer relationships? Approach: We have done a qualitative study with an inductive approach. Primary data has been collected through seven qualitative semi-structured interviews with persons from different companies. Conclusions: After investigating this subject we have come to the conclusion that using smartphones as a marketing channel can help companies to pinpoint their marketing because of the device’s availability and because that the phone is personal to the customer. We mean that customers’ acceptance and integrity is very important to take into consideration and will be of great importance in how well companies will succeed in its use of smartphones as a marketing channel. Timing is another important question and we have therefore presented two new concepts; business-driven timing and customer-driven timing. Smartphones has also contributed with new strategies when it comes to market segmentation. We suggest place and context as new market segmentation variables so that companies could be able to find their customer in right place and in right time. We have also come to the conclusion that smartphones as a marketing channel is advantageous when it comes to building relationship to the customer and we have also seen tendencies that the customer socialize with the brand in a way that they has not been done before. We have also introduced a new concept, interactive communication devices, which is a name for a new type of marketing channels and where smartphones is the leading device today. Keywords: Mobile marketing, precision marketing, customer driven timing[3], market segmentation, context, relevance, integrity, brand, customer relationship, high interactive communication devices[4] [3]This is a new concept that we have introduced and is a part of a model that we have created. See page 58, chapter 5.1.1 [4]This is a new concept that we have introduced and is a concept for a new type of marketing channel, see page 63, chapter 5.1.3.

The topic of this thesis is the institutional ecology surrounding mobile wireless telecommunication services in Canada. The primary focus is the disconnect between policy pronouncements promoting universal adoption of mobile services, on the one hand, and the fact that mobile adoption remains stubbornly low in both absolute terms and by international comparison. Key concepts in the theory of communication regulation and the historical development of telecommunication policy are laid out, which are used to inform an examination of the development of national mobile communication policy since the 1980s. The thesis then presents two case studies. The first is focused on recent developments in federal mobile policy, directed toward taking greater steps to ensure broad adoption of mobile services. The second examines the changing role of mobile services, from instruments of interpersonal communication to a broader form of information media, and the challenges that this shift has created for policymakers. / October 2015

This thesis aims to examine the role that non-instrumental aspects such as aesthetic and emotion play in elderly user interaction with mobile phones. It presents an analysis of the results from in-depth interviews with a selected group of Swedish elderly users, and discusses how the aesthetic experience which they yield in interacting with mobile phones could impact their preference, and their perceived usability of the devices.  A set of mobile phones, different in usability and aesthetic levels were presented to the group of elderly user in order to investigate how they perceive phones attributes, including appearance and general features, and different facets of their user experience, including their motivations of use, the involved emotions, desires, and concerns. The analyses revealed a possible existing correlation between non-instrumental aspects of elderly users’ interaction with mobile phones, and their preference to use those devices. While negative aesthetic experience as a result of social concerns had a strong negative influence on elderly’s perceived usability, and could consequently alter their preference, certain symbolic meanings in interaction such as the tendency to be modern, contributed to perceived ease-of-use & perceived usefulness of the mobile phones. Elderly user’s familiarity or earlier experience with a device or with the technology was found to be a confounding variable. However, in the presence of usability concerns, traditional factors of aesthetic went into the shadow, and therefore had no direct impact on users’ perceived usability of the device. A set of design solutions that would address elderly user’ both instrumental and non-instrumental concern, were proposed.

Στην παρούσα διδακτορική διατριβή εξετάζονται οι δυνατότητες που προσφέρουν τα έξυπνα κινητά τηλέφωνα (smartphones) στην παροχή υπηρεσιών φροντίδας σε άτομα με χρόνιες παθήσεις, μέσω των τεχνολογιών τηλεματικής. Για το σκοπό αυτό μελετήθηκε, σχεδιάστηκε και αναπτύχθηκε ένα δίκτυο φορετών ασύρματων αισθητήρων για την αναγνώριση της φυσικής δραστηριότητας, το οποίο καταγράφει δεδομένα της κίνησης και βιολογικά σήματα, τα οποία στη συνέχεια επεξεργάζονται για την αναγνώριση της δραστηριότητας που εκτελείται, σε πραγματικό χρόνο. Σε σχέση με τις μέχρι σήμερα προσεγγίσεις, στην παρούσα εργασία γίνεται συγκριτική μελέτη πολλαπλών τεχνικών αναγνώρισης προτύπων καθώς και τεχνικών που δεν έχουν χρησιμοποιηθεί μέχρι σήμερα, ενώ γίνεται εξέταση των αποτελεσμάτων που προκύπτουν κάνοντας χρήση του συνδυασμού μικρότερου αριθμού δεδομένων. Η πληροφορία της αναγνώρισης της φυσικής δραστηριότητας συνδυάζεται στη συνέχεια με περιβαλλοντικά δεδομένα, ώστε να μελετηθούν τα μοτίβα της καθημερινής δραστηριότητας υγειών ατόμων και ατόμων με χρόνιες παθήσεις. Με την αναζήτηση Emerging Patterns στα αποθηκευμένα δεδομένα, εξετάζεται ο βαθμός συμμόρφωσης στις ιατρικές οδηγίες, αλλά οι δυνατότητες πρόβλεψης των βραχυπρόθεσμων και μακροπρόθεσμων επιπλοκών των χρόνιων παθήσεων. / The present PhD thesis examines the potentials of the usage of the smartphones in order to offer health services to patients with chronic diseases. A wearable wireless sensor network designed and developed in order to record body movement and biosignal data. Physical activity recognition techniques are applied to the recorded data, so that to extract the actual activities performed, in real time. In contrast to the research that has been carried out till today, an extensive comparison between different pattern recognition techniques is performed using all the recorded data and a reduced number of them, applying newly proposed pattern recognition. Furthermore, the recognized physical activities are combined with environmental data, in order to study the daily activity patterns of healthy persons and persons with chronic diseases. Searching for Emerging Patterns in the data, patient conformance to the medical advices, along with short and long term complications of chronic diseases are examined.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T20:48:08Z No. of bitstreams: 1 MarceloDamascenoDeMelo_TESE.pdf: 2910788 bytes, checksum: 7a6cf94738a8f5339537bc4eca9e187f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-14T00:30:34Z (GMT) No. of bitstreams: 1 MarceloDamascenoDeMelo_TESE.pdf: 2910788 bytes, checksum: 7a6cf94738a8f5339537bc4eca9e187f (MD5) / Made available in DSpace on 2016-10-14T00:30:34Z (GMT). No. of bitstreams: 1 MarceloDamascenoDeMelo_TESE.pdf: 2910788 bytes, checksum: 7a6cf94738a8f5339537bc4eca9e187f (MD5) Previous issue date: 2016-03-07 / Verificar a identidade de usu?rios ? um problema enfrentado diariamente por pessoas e sistemas que autorizam o acesso de pessoas levando em conta caracter?sticas f?sicas e documentos apresentados. Entretanto, esfor?os ainda precisam ser aplicados na resolu??o de quest?es relacionadas a precis?o do sistema verificador e na falsifica??o de objetos e informa??es pessoais.Assim, o uso de biometria pode minimizar ou resolver estas dificuldades. Infelizmente, a substitui??o de tra?os biom?tricos em caso de comprometimento na seguran?a de sistemas biom?tricos ? dificultoso. Deste modo, o uso de fun??es n?o invers?veis ? proposto com o objetivo de distorcer os tra?os biom?tricos, adicionando assim a caracter?stica cancel?vel aos dados biom?tricos. Esta tese analisa algumas solu??es para verifica??o de usu?rios atrav?s do uso de biometrias comportamentais cancel?veis. Especificamente, as solu??es s?o baseadas no TouchAlytics, uma base de dados com tra?os realizados por usu?rios em uma tela touchscreen presente em smartphones. As solu??es analisadas contituem no uso de classificadores e comit? de classificadores para resolu??o do problema de verifica??o de usu?rios. Al?m das solu??es descritas, esta tese analisa o uso de m?ltiplos template biom?trico cancel?veis utilizando um comit? de classificadores (Esquemas de Prote??o de Privacidade M?ltipla). Esta tese tamb?m apresenta uma discuss?o facetada do impacto da chave em uma fun??o cancel?vel. Para isso, apresentamos um estudo emp?rico na qual utiliza chave ?nica ou chaves diferentes para prote??o dos templates biom?tricos dos usu?rios. Al?m disso, um estudo do impacto do tamanho da chave na precis?o de um sistema de verifica??o biom?trico ? discutido. A partir dos resultados encontrados, a gerac?o e armazenamento da chave cancel?vel em telefones m?veis ? analisado. N?s demostramos que o uso de fun??es de tranforma??o geralmente fornece performance similar ou superior a performance dos templates sem prote??o (dados Original), exceto usando a func?o BioHashing. O uso de m?ltiplos templates protegidos processados por comit?s de maquina superaram os resultados do uso de classificadores e comit?s de m?quina. Al?m do mais, n?s mostramos que os sistemas biom?tricos que utilizam templates cancel?veis preservam a privacidade do usu?rio, ou seja, fornecem baixa Taxa de Falsa Aceita??o e Falsa Rejei??o em ataques de chave desconhecida e performance similar a templates desprotegidos em ataques com chave conhecida. Baseado nos experimentos de comprimento de chave, n?s observamos uma melhora cont?nua quando o comprimento da chave aumenta nas fun??es Interpola??o e BioHashing em ambos os ataques de chave. A fun??o Soma Dupla teve melhora inferior mas o importante ? que a performance n?o diminui com o aumento do comprimento da chave. Concluindo, baseado em nossos resultados, n?s propomos o uso de uma chave de usu?rio ?nica gerada por sistema para autentica??o de usu?rio em dispositivos m?veis usando m?ltiplos templates biom?tricos cancel?veis. / The verification of user identity is a faced daily problem to people or system that authorize the acess of people taking account the physical and document characteristics.However, efforts need to be spend to resolve related questions to accuracy of verification system and in the falsification of objects and personal information.Thus, biometrics proposes minimize and resolve these difficulties.Unfortunately, the substitution of biometric traces in the case of compromise is difficult.Hence, the use of non-invertible functions is proposed to distort the biometric traces.Consequently, this procedures allows that biometric templates becomes cancelable or revocable.This thesis analysis some solution to user verification using cancelable behavioural biometrics.The analysed solutions are based on the use of single classifiers and ensemble system to resolve the user verification problem.In addition, this thesis analysis the use of multiple cancelable templates using ensemble system (Multiple-Privacy Protection Schemes).This thesis also presents a discussion of key impact in a cancelable function.Thus, we show a empiric study of use of single or different key values to enrolled users.Moreover, a study of the impact of key length is discussed based on the accuracy of biometric system.Based on the results, it is discussed the generation and storage of cancelable keys in mobile devices. In summary, we have demonstrated that the use of a transformation function usually provides similar or better performance than Original biometric data, except in BioHashing function.In addition, the use of multiple protected templates processed by ensemble system outperformed the previous results in single classifiers and ensemble system.Moreover, we showed that biometric system with cancelable templates preserves the user privacy, i.e, it provides lower False Acceptance and False Rejection Errors in Unknown Key attacks and similar performance to unprotected biometric samples in Known Key Attacks.Based on key length experiments, we observe a perceptible continuous improvement when the key increases in Interpolation and BioHashing method in both key knowledge attacks.In contrast, Double Sum have minor improvements but the most important is the performance does not decrease when the key increases.In conclusion, based on our findings, we proposes the use of a key generated by system to authenticate users in mobile devices using cancelable biometric templates.

Submitted by PATTRISCE RAYMUNDO DE VASCONCELOS (pattrisce@gmail.com) on 2015-01-14T23:43:42Z No. of bitstreams: 1 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2644908 bytes, checksum: b75abbaae8763627d3bf6f1af952eaf4 (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2015-01-19T12:39:54Z (GMT) No. of bitstreams: 1 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2644908 bytes, checksum: b75abbaae8763627d3bf6f1af952eaf4 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-01-30T12:16:25Z (GMT) No. of bitstreams: 1 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2644908 bytes, checksum: b75abbaae8763627d3bf6f1af952eaf4 (MD5) / Made available in DSpace on 2015-01-30T12:16:40Z (GMT). No. of bitstreams: 1 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2644908 bytes, checksum: b75abbaae8763627d3bf6f1af952eaf4 (MD5) Previous issue date: 2014-10-29 / Item withdrawn by Marcia Bacha (marcia.bacha@fgv.br) on 2015-04-29T17:17:17Z Item was in collections: EBAPE - Dissertações, Mestrado Acadêmico em Administração (ID: 48) No. of bitstreams: 3 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf.jpg: 1515 bytes, checksum: 9703fe1c65437f3c11a3a2b2b6ab6a16 (MD5) Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf.txt: 192822 bytes, checksum: 9fb03a13d8396b9cba232b8acf919886 (MD5) Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2601075 bytes, checksum: e04837e975c5750351ed1fa46736e2be (MD5) / Item reinstated by Marcia Bacha (marcia.bacha@fgv.br) on 2015-04-29T17:18:11Z Item was in collections: EBAPE - Dissertações, Mestrado Acadêmico em Administração (ID: 48) No. of bitstreams: 3 Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf.jpg: 1515 bytes, checksum: 9703fe1c65437f3c11a3a2b2b6ab6a16 (MD5) Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf.txt: 192822 bytes, checksum: 9fb03a13d8396b9cba232b8acf919886 (MD5) Dissertação de Pattrisce Vasconcelos - Aplicativos Móveis de Taxi_ULTIMA VERSAO.pdf: 2601075 bytes, checksum: e04837e975c5750351ed1fa46736e2be (MD5) / The research aims to investigate the key success factors in the adoption of mobile taxi applications (AMTs) by taxi drivers. Based on the Technology Acceptance model (DAVIS, BAGOZZI, WARSHAW, 1989), Diffusion of Innovation (ROGERS, 1995) and Trust (CARTER; BÉLANGER, 2005), the paper also proposes a review of the literature applied to the Mobile Application context of AMTs (VAN BILJON; Kotze, 2007). For the purpose of the research, the AMTs are defined as mobile service advanced applications which enable, through Internet and geolocation, a taxi transportation request in mobile devices, by means of information systems and phone calls, also monitoring the service provision and payment. Based on semi-structured interviews and questionnaires applications in field research, the study proposes a triangulation of the methods Lexical Analysis (BOTTA,2010; GEERAERTS,2010), Content Analysis (BARDIN, 2006), and Average Ranking (OLIVEIRA, 2005) for the investigation of the identified factors in the literature. The results indicate that the success factors influencing the adoption of AMTs by taxi drivers, are Simplicity and Perceived Usefulness, while moderators are Security and Financial Gains. It is believed that the research can contribute to the discussion of a topic still few explored in the literature in Brazil, Mobile Applications, and provide managerial implications for innovation in applications development companies. / A pesquisa tem como objetivo investigar os fatores-chave de sucesso na adoção de aplicativos móveis de táxi (AMTs) por taxistas. Baseando-se nos modelos de Aceitação Tecnológica (DAVIS; BAGOZZI; WARSHAW, 1989), Difusão da Inovação (ROGERS, 1995) e de Confiança (CARTER; BÉLANGER, 2005), o trabalho propõe também uma revisão da literatura de Aplicações Móveis aplicada ao contexto dos AMTs (VAN BILJON; KOTZÉ, 2007). Para o propósito dessa pesquisa, os AMTs são definidos como aplicativos de serviço móvel avançado que viabilizam, por meio de Internet e geolocalização, a solicitação de transporte de táxi em dispositivos móveis, mediante sistemas de informação e chamadas telefônicas, e o acompanhamento da prestação do serviço e seu pagamento. A partir de entrevistas semiestruturadas em profundidade e aplicações de questionários em pesquisa de campo, o estudo propõe uma triangulação de métodos de Análise Lexical (BOTTA,2010; GEERAERTS,2010), Conteúdo (BARDIN,2006) e Ranking Médio (OLIVEIRA,2005) para a investigação dos fatores identificados na literatura. Os resultados apontam que os fatores influenciadores do sucesso dos AMTs, na perspectiva de uso pelos motoristas de táxi, são Simplicidade e Utilidade Percebida, enquanto os moderadores são Segurança e Ganhos Financeiros. Acredita-se que a pesquisa poderá contribuir para a discussão de um tema ainda pouco explorado na literatura no Brasil, os Aplicativos Móveis, além de proporcionar implicações gerenciais no âmbito da inovação em empresas desenvolvedoras.

Submitted by Milena Rubi (milenarubi@ufscar.br) on 2017-06-01T17:49:19Z No. of bitstreams: 1 SILVA_Tiago_2016.pdf: 13631569 bytes, checksum: 7774c3913aa556cc48c0669f686cd3b5 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-06-01T17:49:26Z (GMT) No. of bitstreams: 1 SILVA_Tiago_2016.pdf: 13631569 bytes, checksum: 7774c3913aa556cc48c0669f686cd3b5 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-06-01T17:49:32Z (GMT) No. of bitstreams: 1 SILVA_Tiago_2016.pdf: 13631569 bytes, checksum: 7774c3913aa556cc48c0669f686cd3b5 (MD5) / Made available in DSpace on 2017-06-01T17:49:38Z (GMT). No. of bitstreams: 1 SILVA_Tiago_2016.pdf: 13631569 bytes, checksum: 7774c3913aa556cc48c0669f686cd3b5 (MD5) Previous issue date: 2016-07-01 / Não recebi financiamento / The rapid popularization of smartphones has contributed to the growth of SMS usage as an alternative way of communication. The increasing number of users, along with the trust they inherently have in their devices, makes SMS messages a propitious environment for spammers. In fact, reports clearly indicate that volume of mobile phone spam is dramatically increasing year by year. SMS spam represents a challenging problem for traditional filtering methods nowadays, since such messages are usually fairly short and normally rife with slangs, idioms, symbols and acronyms that make even tokenization a difficult task. In this scenario, this thesis proposes and then evaluates a method to normalize and expand original short and messy SMS text messages in order to acquire better attributes and enhance the classification performance. The proposed text processing approach is based on lexicography and semantic dictionaries along with the state-of-the-art techniques for semantic analysis and context detection. This technique is used to normalize terms and create new attributes in order to change and expand original text samples aiming to alleviate factors that can degrade the algorithms performance, such as redundancies and inconsistencies. The approach was validated with a public, real and non-encoded dataset along with several established machine learning methods. The experiments were diligently designed to ensure statistically sound results which indicate that the proposed text processing techniques can in fact enhance SMS spam filtering. / A popularização dos smartphones contribuiu para o crescimento do uso de mensagens SMS como forma alternativa de comunicação. O crescente número de usuários, aliado à confiança que eles possuem nos seus dispositivos tornam as mensagem SMS um ambiente propício aos spammers. Relatórios recentes indicam que o volume de spam enviados via SMS está aumentando vertiginosamente nos últimos anos. SMS spam representa um problema desafiador para os métodos tradicionais de detecção de spam, uma vez que essas mensagens são curtas e geralmente repletas de gírias, símbolos, abreviações e emoticons, que torna até mesmo a tokenização uma tarefa difícil. Diante desse cenário, esta dissertação propõe e avalia um método para normalizar e expandir amostras curtas e ruidosas de mensagens SMS de forma a obter atributos mais representativos e, com isso, melhorar o desempenho geral na tarefa de classificação. O método proposto é baseado em dicionários lexicográficos e semânticos e utiliza técnicas modernas de análise semântica e detecção de contexto. Ele é empregado para normalizar os termos que compõem as mensagens e criar novos atributos para alterar e expandir as amostras originais de texto com o objetivo de mitigar fatores que podem degradar o desempenho dos métodos de classificação, tais como redundâncias e inconsistências. A proposta foi avaliada usando uma base de dados real, pública e não codificada, além de vários métodos consagrados de aprendizado de máquina. Os experimentos foram conduzidos para garantir resultados estatisticamente corretos e indicaram que o método proposto pode de fato melhorar a detecção de spam em SMS.