No description available.

While today's   police forces are decreasing in number and their resources are limited,   population is at the same time increasing. This means that other types of   efforts and strategies are needed to fight crime. There are different   strategies to do this, one of which is called community policing that   involves proactive cooperation between citizens and the police to deal with   the problems. Traditionally, community policing meant that a local police in   the neighbourhood called for physical meetings, where citizens and police   together raised problems and discussed solutions to these. With today's   limited resources, there is little possibilities for the police to execute   this kind of physical collaboration and meetings. On the other hand, another   meeting place has been added (the one online) and an alternative way to   implement community policing may be online. With digital channels for this   purpose, there may also be an opportunity to reach groups of citizens that   the police have not reached before, but in order to do so, it requires work   and a use of these digital channels in the right way according to community   policing. The purpose of   this paper is to investigate what challenges and requirements that needs to   be taken into consideration when implementing community policing with the   support of digital communication channels. For this purpose, qualitative   research in the form of literature studies and semi-structured interviews   were conducted. Findings show   there are a lot of challenges and requirements to consider and there are   guidelines in the analysis and discussion section, to help begin to implement   this way of working. The practical   implications for this thesis may help police improving their relationships   with citizens in vulnerable areas to be able to cooperate according to   community policing to make these areas a better and safer place to live.

通訊產業在本世紀快速成長，吸引眾多廠商投入，但是基於激烈的變化，讓經營生態產生劇烈震盪，在這種背景下，本研究決定選擇通訊通路作為研究的標的，針對國內一家通訊通路企業的現有經營策略及策略規劃進行深入分析。因為策略不但要適應環境的變化，也要符合被規劃者本身的條件與目標，故本研究以個案研究的方式，選擇其做為研究。期待透過深入的訪談與分析，找出在這個競爭激烈的產業中，何者為得以脫穎而出的原因。 歸結來說，本研究透過個案研究法，以國內通訊通路業者作為研究個案，歷時七個多月的調查與分析，獲得以下主要結論： 1.國內通訊通路業的關鍵成功因素為: 上下游關係、規模經濟以及增加本身之附加價值。 2.從內外在環境分析及條件前提來看，個案公司最適合採行產品發展策略，本研究依據營業收入、獲利率、風險程度及市場佔有率的評估準則，分別給予不同權重，建議個案公司先發展PHS行動配件包。 3.個案公司的未來成長策略可選擇產品多角化與市場擴充策略，最能發揮個案公司的核心能力，並能繼續累積未來的競爭武器。在產品多角化的競爭策略為採取產品差異化集中路線，針對明確的網路發展架構為基礎發展新產品，持續增加競爭優勢，以提高營業收入、市場佔有率以及獲利率，並降低風險。在市場擴充上，勢必得朝大陸發展，以期另創新局。

In recent years, the security of networked control systems (NCSs) has been an important challenge for many researchers. Although the security schemes for networked control systems have advanced in the past several years, there have been many acknowledged cyber attacks. As a result, this dissertation proposes the use of a novel time-delay switch (TDS) attack by introducing time delays into the dynamics of NCSs. Such an attack has devastating effects on NCSs if prevention techniques and countermeasures are not considered in the design of these systems. To overcome the stability issue caused by TDS attacks, this dissertation proposes a new detector to track TDS attacks in real time. This method relies on an estimator that will estimate and track time delays introduced by a hacker. Once a detector obtains the maximum tolerable time delay of a plant’s optimal controller (for which the plant remains secure and stable), it issues an alarm signal and directs the system to its alarm state. In the alarm state, the plant operates under the control of an emergency controller that can be local or networked to the plant and remains in this stable mode until the networked control system state is restored. In another effort, this dissertation evaluates different control methods to find out which one is more stable when under a TDS attack than others. Also, a novel, simple and effective controller is proposed to thwart TDS attacks on the sensing loop (SL). The modified controller controls the system under a TDS attack. Also, the time-delay estimator will track time delays introduced by a hacker using a modified model reference-based control with an indirect supervisor and a modified least mean square (LMS) minimization technique. Furthermore, here, the demonstration proves that the cryptographic solutions are ineffective in the recovery from TDS attacks. A cryptography-free TDS recovery (CF-TDSR) communication protocol enhancement is introduced to leverage the adaptive channel redundancy techniques, along with a novel state estimator to detect and assist in the recovery of the destabilizing effects of TDS attacks. The conclusion shows how the CF-TDSR ensures the control stability of linear time invariant systems.

Actualmente, hay una tendencia de aumento de uso de canales de Comunicación Interna en las empresas para asegurar una comunicación efectiva y aumentar el desempeño de sus colaboradores. Esta investigación tiene como objetivo identificar la preferencia en canales de comunicación interna (CI) de los colaboradores operativos de una empresa industrial, en el Perú, para sentirse comprometidos con la misma. Para lograr el objetivo, se planea dividir los canales usados por la organización en dos grupos: digitales y humanos, para detallar las dimensiones de CI valoradas por los participantes según cada canal y describir la relación de cada uno con los distintos componentes de engagement valorados por los colaboradores. La metodología de la investigación se desarrollará bajo el enfoque cualitativo, con un diseño de teoría fundamentada; la técnica de recolección de datos será la entrevista semiestructurada. / Currently, there is an increasing trend in the use of Internal Communication channels in companies to ensure effective communication and increase the performance of their employees. This study aims to identify relationship between the blue collar workers preference of internal communication channel and the level of engagement with the company in Peru. To develop this study, the channels used by the organization will be divided into two groups: digital channels and human channels, to analyze the internal communication dimensions. This study classified the opinions of the participants according to each channel and describe the relationship of each one with the different components of engagement valued by collaborators. Following the approach of grounded theory methodology design, semi-structured interviews were conducted for data collection. / Trabajo de investigación

Optical Transport Network is a set of Optical Network Elements (NE) connected by optical fiber links able to provide support for optical networking using Wavelength-Division Multiplexing (WDM). In order to be able to introduce link-level applications that require NE-to-NE communication in a packet-optical network, an embedded communication channel is needed. Examples of such applications are dual-ended protection, remote configurationand path trace. By implementing a NE-to-NE communication channel, the exchange of commands and information will allow for implementation of applications that will increase the data link stability in the network. The purpose of this work has been to prove the feasibility of such a channel. This thesis discusses the possibilities of implementing such a channel adjusted to Transmode's layer 1 products without causing disturbance inthe regular traffic or affecting any existing embedded communication. It also proves the channels function in a proof-of-concept manner by demonstrating a simple Path trace application run upon an implementation of the channel on hardware. The chosen solution is an Embedded Communication Channel driver intended to provide termination points for an Embedded Communication Channel (ECC), supervising the connectivity of the channel and relay messages to applications. This thesis project has been carried out at Infinera Corporation (earlier Transmode Systems AB) during summer/autumn 2015.

Dans cette thèse nous nous sommes principalement concentrés sur les transmissions impulsion radio Ultra Large Bande (UWB-IR) qui a plusieurs avantages grâce à la nature de sa bande très large (entre 3.1GHZ et 10.6GHz) qui permet un débit élevé et une très bonne résolution temporelle. Ainsi, la très courte durée des impulsions émises assure une transmission robuste dans un canal multi-trajets dense. Enfin la faible densité spectrale de puissance du signal permet au système UWB de coexister avec les applications existantes. En raison de toutes ces caractéristiques, la technologie UWB a été considérée comme une technologie prometteuse pour les applications WSN. Cependant, il existe plusieurs défis technologiques pour l'implémentation des systèmes UWB. A savoir, une distorsion différente de la forme d'onde du signal reçu pour chaque trajet, la conception d'antennes très larges bandes de petites dimensions et non coûteuses, la synchronisation d'un signal impulsionnel, l'utilisation de modulation d'onde d'ordre élevé pour améliorer le débit etc. Dans ce travail, Nous allons nous intéresser à l'étude et l'amélioration de la synchronisation temporelle dans les systèmes ULB. / The basic concept of Impulse-Radio UWB (IR-UWB) technology is to transmit and receive baseband impulse waveform streams of very low power density and ultra-short duration pulses (typically at nanosecond scale). These properties of UWB give rise to fine time-domain resolution, rich multipath diversity, low power and low cost on-chip implementation facility, high secure and safety, enhanced penetration capability, high user capacity, and potential spectrum compatibility with existing narrowband systems. Due to all these features, UWB technology has been considered as a feasible technology for WSN applications. While UWB has many reasons to make it a useful and exciting technology for wireless sensor networks and many other applications, it also has some challenges which must be overcome for it to become a popular approach, such as interference from other UWB users, accurate modelling of the UWB channel in various environments, wideband RF component (antennas, low noise amplifiers) designs, accurate synchronization, high sampling rate for digital implementations, and so on. In this thesis, we will focus only on one of the most critical issues in ultra wideband systems: Timing Synchronization.

A modelagem computacional tem se tornado uma poderosa ferramenta utilizada mundialmente em pesquisas sobre sistemas de comunicação móvel. Em tais sistemas, a modelagem do canal é fator indispensável, pois as características de mobilidade e propagação presentes nesse tipo de sistema são responsáveis por distorções ocorridas sobre o sinal transmitido. O presente trabalho reúne os principais modelos matemáticos e computacionais de canal de comunicação móvel. Realiza-se uma abordagem histórica sobre o assunto, apresentado a natureza do problema do desvanecimento e a forma como foi modelado inicialmente. Por outro lado, apresentam-se modelos recentes, considerados eficazes do ponto de vista matemático e eficientes do ponto de vista computacional. O trabalho traz como contribuição a proposta de um novo modelo de canal com desvanecimento. Os modelos apresentados foram analisados do ponto de vista matemático por meio de suas propriedades estatísticas. Do ponto de vista numérico e computacional a análise se deu por meio de simulações. A principal conclusão obtida mostra que dois modelos com filtragem no domínio da freqüência, sendo um deles o novo modelo proposto, são os mais indicados para simular formas de onda que representem um canal com desvanecimento Rayleigh. Este trabalho tem a pretensão de ser útil para pesquisadores atuantes na área de modelagem e simulação de sistemas atuais de comunicação móvel. / Computational modelling is a powerful and widely used tool for research in mobile communication systems. In such systems, the communication channel modelling is an indispensable factor, because its mobility and propagation characteristics can cause distortion over the transmitted waveform. This work contains the main mathematical and computing communication channel models. A historical cover is provided, which presents the nature of the problem and the initial modelling of the fading phenomenon. On the other hand, recent models are presented, which are mathematically effective and computationally efficient. One contribution of this work is the proposal of a new fading channel computational model, which was suitably tested and validated. The presented models were mathematically analyzed through its statistical properties. From numerical and computational point of view, the models were analyzed through several simulations. The main conclusion, from analytical and simulated results, shows that two models using frequency filtering are the best choice for the generation of multiple uncorrelated Rayleigh fading waveforms, where one of them is the new proposed model. This work can help mobile communications researchers to suitably model the communication channel in a computer simulation.

A modelagem computacional tem se tornado uma poderosa ferramenta utilizada mundialmente em pesquisas sobre sistemas de comunicação móvel. Em tais sistemas, a modelagem do canal é fator indispensável, pois as características de mobilidade e propagação presentes nesse tipo de sistema são responsáveis por distorções ocorridas sobre o sinal transmitido. O presente trabalho reúne os principais modelos matemáticos e computacionais de canal de comunicação móvel. Realiza-se uma abordagem histórica sobre o assunto, apresentado a natureza do problema do desvanecimento e a forma como foi modelado inicialmente. Por outro lado, apresentam-se modelos recentes, considerados eficazes do ponto de vista matemático e eficientes do ponto de vista computacional. O trabalho traz como contribuição a proposta de um novo modelo de canal com desvanecimento. Os modelos apresentados foram analisados do ponto de vista matemático por meio de suas propriedades estatísticas. Do ponto de vista numérico e computacional a análise se deu por meio de simulações. A principal conclusão obtida mostra que dois modelos com filtragem no domínio da freqüência, sendo um deles o novo modelo proposto, são os mais indicados para simular formas de onda que representem um canal com desvanecimento Rayleigh. Este trabalho tem a pretensão de ser útil para pesquisadores atuantes na área de modelagem e simulação de sistemas atuais de comunicação móvel. / Computational modelling is a powerful and widely used tool for research in mobile communication systems. In such systems, the communication channel modelling is an indispensable factor, because its mobility and propagation characteristics can cause distortion over the transmitted waveform. This work contains the main mathematical and computing communication channel models. A historical cover is provided, which presents the nature of the problem and the initial modelling of the fading phenomenon. On the other hand, recent models are presented, which are mathematically effective and computationally efficient. One contribution of this work is the proposal of a new fading channel computational model, which was suitably tested and validated. The presented models were mathematically analyzed through its statistical properties. From numerical and computational point of view, the models were analyzed through several simulations. The main conclusion, from analytical and simulated results, shows that two models using frequency filtering are the best choice for the generation of multiple uncorrelated Rayleigh fading waveforms, where one of them is the new proposed model. This work can help mobile communications researchers to suitably model the communication channel in a computer simulation.

Made available in DSpace on 2010-04-20T20:14:43Z (GMT). No. of bitstreams: 1 61080100031.PDF: 7443816 bytes, checksum: a82ca7f98a374b3f75cdb221b7fb942b (MD5) Previous issue date: 2010-02-22T00:00:00Z / O impacto do boca a boca na Imagem da Marca e no julgamento de produtos (bens e serviços) tem sido estudado há tempos na disciplina de comportamento do consumidor. Com o crescimento da internet como mídia social e meio de comunicação entre consumidores e empresas, o boca a boca ganhou força junto a profissionais e pesquisadores de Marketing. Uma revisão da literatura permitiu traçar um paralelo entre o boca a boca tradicional e o eletrônico. É preciso compreender cientificamente a influência do boca a boca eletrônico no comportamento do consumidor. Para isto, foram realizados dois estudos nesta dissertação, sendo o primeiro um estudo exploratório a partir da realização de entrevistas e aplicação de questionários a consumidores, profissionais de Marketing e especialistas do assunto com o intuito de levantar percepções gerais sobre o tema. Para avaliar estatisticamente as hipóteses propostas nesta dissertação, o segundo estudo foi a realização de um experimento com 168 estudantes, contando com cinco cenários e três tipos de produtos (Vestuário, Cosméticos e Lojas Online). A variável independente foi o Comentário Postado pelo consumidor. Duas foram as variáveis dependentes: Imagem da Marca e Intenção de Compra dela. Para a mensuração da Imagem da Marca se utilizou a escala de Personalidade de Marca de Aaker (1997). No tocante à Intenção de Compra, um concurso foi elaborado para os sujeitos. No início e no final da coleta de dados, os participantes escolhiam as empresas das quais ganhariam um prêmio (vale compra), caso fossem os vencedores. Mediu-se a Intenção de Compra em função da escolha dos consumidores antes e depois do estímulo, sendo comparados, ainda, os resultados dos diferentes cenários. Constatou-se que os comentários negativos e positivos que os consumidores postam na internet têm um impacto significante na Imagem da Marca para outros consumidores nos produtos Vestuário e Loja Online. Mas não foram percebidos impactos destes comentários na Imagem da Marca no produto Cosmético e na Intenção de Compra dos outros consumidores nos três tipos de produtos testados. O Gerenciamento dos Comentários negativos (resposta da empresa a comentário postado pelo consumidor) apresentou uma redução no impacto do comentário na Imagem da Marca para os outros consumidores no produto Loja Online. Contudo, os tons alinhados com Foco Regulatório do consumidor nas respostas das empresas não provocaram diferenças significativas, contra indicando essa concepção teórica como meio de aprimorar os resultados do Gerenciamento dos Comentários. Várias implicações científicas e profissionais interessantes decorrem da pesquisa. Para o praticante, se viu que a internet 2.0 é uma mídia a ser considerada no esforço de comunicação da empresa e que ela deve ser considerada como um canal de comunicação bidirecional. / The impact of Word of Mouth Communication on Brand Image and the evaluation of products (goods and services) has been studied for some time in the discipline of consumer behavior. With the growth of the Internet as a social media and as a means of communication between consumers and enterprises, Word of Mouth has gained strength with Marketing professionals and researchers. A review of the literature draws a parallel between traditional Word of Mouth and its electronic version. It is essential to understand scientifically the influence of Electronic Word of Mouth on consumer behavior. In order to do this, two main studies were made: the first one was an exploratory stage conducted with interviews and questionnaires applied to consumers, marketers, and experts on the subject in order to raise general perceptions on the issue. The second study aims to evaluate statistically the hypotheses proposed in this work and involves an experiment applied to 168 students, considering five scenarios and three types of products (clothing, cosmetics and Online Stores). The independent variable was the Comment Posted by the consumer on the internet. Two were the dependent variables: Brand Image and Purchase Intention. To measure Brand Image, the scale "The Brand Personality" by Aaker (1997) was used. To measure Purchase Intention subjects participated in a contest where they chose, at the beginning and end of data collection, the companies from which they would gain a gift certificate, if they won the contest. Purchase Intention was measured depending on the choice of consumers before and after the stimulus, and compared also the results of different scenarios. It was found that the positive and negative comments that consumers posted on the internet have a significant impact on Brand Image for other consumers of products in Clothing and Online stores. However, there was no perceived impact based on these comments regarding Cosmetic products. No impact was found on other consumers' Purchase Intention. Management of Negative Comments (company's response to comments posted by the consumer on the internet) decreased the negative impact of comments on other consumer's Brand Image on product Online Store and the use of Regulatory Focus Theory on companies' responses did not cause significant differences, counter indicating this theoretical concept as a mean to improve the results of managing the comments posted by the consumer on the internet. Several implications of scientific and professional interest arise from this research. For a Marketing professional, it is evident that internet 2.0 should be considered in the media plan of a company and that it should be treated as a two-way communication channel with consumers.