Dissertations / Theses on the topic 'Open throat'

The technique of 'open throat' is a pedagogical concept transmitted through the oral tradition of singing. This thesis explored the pedagogical perceptions and practices of 'open throat' using empirical methodologies to assess technical skill and associated vocal quality. In the first study (Mitchell, Kenny, Ryan, & Davis, 2003), we assessed the degree of consensus amongst singing pedagogues regarding the definition of, and use in the singing studio of the technique called 'open throat.' Results indicated that all fifteen pedagogues described 'open throat' technique as fundamental to singing training and were positive about the sound quality it achieved, especially in classical singing. It was described as a way of maximising pharyngeal space or abducting the false vocal folds. Hypotheses generated from pedagogical beliefs expressed in this first study were then tested acoustically (Mitchell & Kenny, 2004a, 2004b). Six advanced singing students sang in two conditions: 'optimal' (O), using maximal open throat, 'sub-optimal' (SO), using reduced open throat and loud sub-optimal (LSO) to control for the effect of loudness. From these recordings, acoustic characteristics of vibrato (Mitchell & Kenny, 2004b) and energy distribution (Mitchell & Kenny, 2004a) were examined. Subsequent investigations of the vibrato parameters of rate, extent and onset, revealed that extent was significantly reduced and onset increased when singers did not use the technique. As inconsistent vibrato is considered indicative of poor singing, it was hypothesized that testing the energy distribution in these singers' voices in each condition would identify the timbral changes associated with open throat. Visual inspection of long term average spectra (LTAS) confirmed differences between O and SO, but conventional measures applied to long term average spectra (LTAS), comparing energy peak height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were not sensitive to the changes identified through visual inspection of the LTAS. These results were not consistent with the vibrato findings and suggest that conventional measures of SPR and ER are not sufficiently sensitive to evaluate LTAS. In the fourth study, fifteen expert listeners consistently and reliably identified the presence of open throat technique with 87% accuracy (Mitchell & Kenny, in press). In the fifth study, LTAS measurements were examined with respect to the perceptual ratings of singers. There was no relationship between perceptual rankings of vocal beauty and acoustic rankings of vocal quality (Kenny & Mitchell, 2004, in press). There is a vast literature of spectral energy definitions of good voice but the studies in this thesis have indicated that current acoustic methods are limited in defining vocal quality. They also suggest that current work in singing has not sufficiently incorporated perceptual ratings and descriptions of sound quality or the relationship between acoustic and perceptual factors with pedagogical practices.

The technique of �open throat� is a pedagogical concept transmitted through the oral tradition of singing. This thesis explored the pedagogical perceptions and practices of �open throat� using empirical methodologies to assess technical skill and associated vocal quality. In the first study (Mitchell, Kenny, Ryan, & Davis, 2003), we assessed the degree of consensus amongst singing pedagogues regarding the definition of, and use in the singing studio of the technique called �open throat.� Results indicated that all fifteen pedagogues described �open throat� technique as fundamental to singing training and were positive about the sound quality it achieved, especially in classical singing. It was described as a way of maximising pharyngeal space or abducting the false vocal folds. Hypotheses generated from pedagogical beliefs expressed in this first study were then tested acoustically (Mitchell & Kenny, 2004a, 2004b). Six advanced singing students sang in two conditions: �optimal� (O), using maximal open throat, �sub-optimal� (SO), using reduced open throat and loud sub-optimal (LSO) to control for the effect of loudness. From these recordings, acoustic characteristics of vibrato (Mitchell & Kenny, 2004b) and energy distribution (Mitchell & Kenny, 2004a) were examined. Subsequent investigations of the vibrato parameters of rate, extent and onset, revealed that extent was significantly reduced and onset increased when singers did not use the technique. As inconsistent vibrato is considered indicative of poor singing, it was hypothesized that testing the energy distribution in these singers� voices in each condition would identify the timbral changes associated with open throat. Visual inspection of long term average spectra (LTAS) confirmed differences between O and SO, but conventional measures applied to long term average spectra (LTAS), comparing energy peak height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were not sensitive to the changes identified through visual inspection of the LTAS. These results were not consistent with the vibrato findings and suggest that conventional measures of SPR and ER are not sufficiently sensitive to evaluate LTAS. In the fourth study, fifteen expert listeners consistently and reliably identified the presence of open throat technique with 87% accuracy (Mitchell & Kenny, in press). In the fifth study, LTAS measurements were examined with respect to the perceptual ratings of singers. There was no relationship between perceptual rankings of vocal beauty and acoustic rankings of vocal quality (Kenny & Mitchell, 2004, in press). There is a vast literature of spectral energy definitions of good voice but the studies in this thesis have indicated that current acoustic methods are limited in defining vocal quality. They also suggest that current work in singing has not sufficiently incorporated perceptual ratings and descriptions of sound quality or the relationship between acoustic and perceptual factors with pedagogical practices.

Phishing is an internet security issue whose shape is still changing and size is still increasing. This thesis shows the possibility of a phishing attack on open, private Wireless LANs. Private WLANs which use a login page to authenticate users in hotels, airports and academic campuses are all vulnerable to this attack. Virginia Tech's WLAN is used as an example to show that the attack is possible. The attack combines two very well known attacks: one is to deceptively guide a user into logging into a fake website, which shows similar log-in page to the page of the website the user intends to go to, and the second attack is to show users a valid certificate, which does not show a warning. The rogue server takes the user to a log-in page which is similar to Virginia Tech's log-in page and shows him a valid security certificate. We present a solution to the proposed problem. Software is implemented that runs on Windows Vista. The software warns the user if there are servers with more than one type of security certificates, claiming to be from the same network. We contrast our method to already existing methods, and show in what respects our solution is better. The biggest advantage of this method is that it involves no change on the server side. It is not necessary for the users to have any prior knowledge of the network, which is very helpful when the users access WLAN at airports and hotels. Also, when using this method, the user does not need to connect to any network, and is still able to get a warning. It however, requires the user to be able to differentiate between the real and fake networks after the user has been warned.
Master of Science

Reverse thrust operations of a model scale Contra-Rotating Open Rotor design were numerically modelled to produce individual rotor thrust and torque results comparable to experimental measurements. The aims of this research were to develop an understanding of the performance and aerodynamics of open rotors during thrust reversal operations and to establish whether numerical modelling with a CFD code can be used as a prediction tool given the highly complex flowfield. A methodology was developed from single rotor simulations initially before building a 3D‘frozen rotor’ steady-state approach to model contra-rotating blade rows in reverse thrust settings. Two different blade pitch combinations were investigated (β1,2 =+30°,- 10° and β1,2 =-10°,-20°). Thrust and torque results compared well to the experimental data and the effects of varying operating parameters, such as rpm and Mach number, were reproduced and in good agreement with the observed experimental behaviour. The main flow feature seen in all the reverse thrust cases modelled, both single rotor and CROR, is a large area of recirculation immediately downstream of the negative pitch rotor(s).This is a result of a large relative pressure drop region generated by the suction surfaces of the negative pitch blades. An initial 3D unsteady sliding-mesh calculation was performed for one CROR reverse thrust case. The thrust and torque values were in poor agreement with experimental values and the disadvantages relating to time costs and required computational resources for this technique were illustrated. However, the results did yield a nominal unsteady variation of thrust and torque due to rotor phase position. Overall the work shows that it may be possible to develop a CROR reverse thrust prediction tool of beneficial quality using CFD models. The research also shows that the frozen rotor approach can be adopted without undermining the fidelity of the results.

In this thesis we develop, evaluate and implement a security solution for Open Controllers wireless sensor network platform. A scenario is used to describe an exemplar application showing how our system is supposed to function. The security of the platform is analyzed using a well-established threat modeling process and attack trees which result in the identification of a number of risks, which could be security weaknesses. These attack trees visualize the security weaknesses in an easy to access way even for individuals without special security expertise. We develop a security solution to counter these identified risks. The developed security solution consists of three different security levels together with a number of new security policies. Each additional level applies different security mechanisms to provide increasingly improved security for the platform. The new security policies ensure that the security solution is continuously secure during its operating time. We implement part of the security solution in the Contiki operating system to assess its function in practice. Finally we evaluate the developed security solution by looking back to the previously identified weaknesses and the implementation proving that the security solution mitigates the risks.

Quality and security of software are key factors in the software development. This thesis deals with the quality of open source software (OSS for short) and different questions that are related with open source and close source software has discussed in the thesis proposal. Open source software is a process by which we can produce cheap and qualitative software and its source could be re-use in the development of the software. Close source software is more expensive than open source software and we can not re-use its source code, so there should be a way by which cheap and qualitative software should be produced. This thesis describes that how the quality of the open source software can be evaluated and increased. There are different factors which are helpful to increase the software quality these factors are low cycle time, low cost and small size of software. These factors are also helpful for the development of software product according to the requirement of clients and the users of that software. This thesis also describes the security and performance of close and open source software and it also analyze different software development processes. The quality of OSS can be increased by use of best evaluation techniques, best quality measurement, best development tools and best development process. There are also many challenges for OSS, which it has to face for improvement of the quality of OSS. Initially there were many drawbacks in open source software but with the passage of time improvement has produced in it. This thesis also describes the compression, advantages and disadvantages of the close source and open source software.
0046-737218653 , 0046-739131829

Artifact-based research provides a mechanism whereby researchers may study the creation of software yet avoid many of the difficulties of direct observation and experimentation. Open source software forges are of great value to the software researcher, because they expose many of the artifacts of software development. However, many challenges affect the quality of artifact-based studies, especially those studies examining software evolution. This thesis addresses one of these threats: the presence of very large commits, which we refer to as "Cliff Walls." Cliff walls are a threat to studies of software evolution because they do not appear to represent incremental development. In this thesis we demonstrate the existence of cliff walls in open source software projects and discuss the threats they present. We also seek to identify key causes of these monolithic commits, and begin to explore ways that researchers can mitigate the threats of cliff walls.

Purpose: The objective of this study is to illustrate how participants in leaderless based projects communicate with each other. Several studies have focused on technology-supported projects, such as open source projects, with an established project manager and goal. There is a lack, to the best of our knowledge, in studies that deal with the communication pattern in a leaderless computer supported collaborative project.

Method: We have chosen to use a quantitative method where we systematically group several messages according to their content. This method was used in a similar study to illustrate the communication between participants involved in an open source project. We have taken the same Kripendorff based method and adapted it to our study by adding more descriptive variables.

Theoretical perspectives: Manuel Castell discusses the aspects of a new communication power that is rooted in the individual as part of a larger creative audience. The collaborative works we have studies are prime examples of how the creative audience works together and of mass self‐communication. In order to analyze the potential motivations behind the participant’s involvement in these collaborative works, we have adopted the ideas of Preece and Shneidermans frame theory. They have identified 4 major roles in most onlinebased co‐operations and refer to them as reader, contributor, collaborator and leader.

Result: Our results show that the communication in computer supported collaborative works is characterized by positive and energetic communication. The participants are all involved by their own will; they contribute because they want to. We believe this to be the major factor influencing the flow and form of communication between the participants. The majority of posts are comments to other participants or contributing posts that add to the progression of the discourse. We also have reason to believe that the use of smileys and embedded pictures is related to the tools available to the participants; the quicker and easier it is to add a picture the more likely the participants will use these tools.

The existance of spam email has gone from a fairly small amounts of afew hundred in the late 1970’s to several billions per day in 2010. Thiscontinually growing problem is of great concern to both businesses andusers alike.One attempt to combat this problem comes with a spam filtering toolcalled TRAP. The primary design goal of TRAP is to enable tracking ofthe reputation of mail senders in a decentralized and distributed fashion.In order for the tool to be useful, it is important that it does not haveany security issues that will let a spammer bypass the protocol or gain areputation that it should not have.As a piece of this puzzle, this thesis makes an analysis of TRAP’s protocoland design in order to find threats and vulnerabilies capable of bypassingthe protocol safeguards. Based on these threats we also evaluate possiblemitigations both by analysis and simulation. We have found that althoughthe protocol was not designed with regards to certain attacks on the systemitself most of the attacks can be fairly easily stopped.The analysis shows that by adding cryptographic defenses to the protocola lot of the threats would be mitigated. In those cases where cryptographywould not suffice it is generally down to sane design choices in the implementationas well as not always trusting that a node is being truthful andfollowing protocol.

In the course of studying the effects of programming in multiple languages, we unearthed troubling trends in SourceForge artifacts. Our initial studies suggest that programming in multiple languages concurrently negatively affects developer productivity. While addressing our initial question of interest, we discovered a pattern of monolithic commits in the SourceForge community. Consequently, we also report on the effects that this pattern of commits can have when using SourceForge as a data-source for temporal analysis of open source projects or for studies of individual developers.

The notion of space being eroded by time underpins the dominant formulations of globalisation premised on time-space compression. The consequences have included the announcement of the ‘end of geography’. More recently, a spatial turn has repositioned the concept of space at the forefront of Human Geography. The aim of this thesis is to contribute to the ongoing theoretical reconceptualisation of space with an empirical study of the contested port city of Fremantle. Set within the broader metropolitan area of Western Australia’s capital city, Perth, Fremantle is simultaneously constructed by local and external actors as a ‘city under threat’ and as a ‘city in decline’. It is the dominant port city of Western Australia and differs in many ways, historically, physically, culturally and economically from its modern, suburban surrounds. Using the question ‘whose city’ in my interactions and observations within Fremantle, I began to see contestations for space emerging.This thesis explores four controversies pertinent to the ongoing battles to define (the meaning of spaces within) Fremantle. The forces of change impacting on Fremantle include de-industrialisation, gentrification, urban entrepreneurialism and heritage construction; however these challenges have served as contingencies which have enabled the opening up of these controversies to other voices. My participant observations, overlayed with a discourse analysis of content from the local Fremantle Herald newspaper across the decade 2000 to 2010, have allowed me to critically engage with these local political controversies. What I found is that, if space is reconceptualised not as a fixed surface but as relational, contested and always in process, then no one group or individual can ever truly claim ownership of or an identity for Fremantle. Consequently what is at issue are the local terms by which competing groups and individuals stake their claims to the ownership or the meaning of the city.Drawing on the work of Doreen Massey, Nigel Thrift and Matthew Rofe, this thesis aims to contribute to the ongoing reconceptualisation of space occurring in contemporary post structuralist scholarship.

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A simulation model was specified. It examines United States Navy Antisubmarine Warfare Screen alternative dispositions for Carrier Battlegroups. The scenario posed is open ocean transit under the threat of an attack from foreign submarine hulls built in the 1990s. The investigation raises the issue of the appropriateness of current Navy practices and suggests that new tactics be developed. The author's thoughts are that there will be ever newer, more lethal, unpredictable threats to United States' maritime independence than current doctrine addresses. The full implementation of the simulation program has not been accomplished. A segment of verification output is shown for expository purposes only. A discussion is given on the adequacy of the model's abstractions along with the possible impact on potential results of experiments.

Oral Biology
M.S.
Objectives: To investigate differences in the modulus of elasticity, tensile strength, and load at breakage for elastic thread alone and elastic thread with gold chain in combination used in force application of palatally impacted and exposed maxillary canines. Methods: Two groups with n=6 in each were tested. A circular portion of elastic thread was cut, tied and measured to the nearest hundredth of a millimeter and recorded. Five links of a gold chain were cut and an elastic thread was tied to the fifth link opposite the bondable eyelet. The length of the elastic thread and the total apparatus was measured to the hundredth of a millimeter and recorded. An Instron with a ramp speed of 100 mm/min was used for all testing. Results: The addition of the gold chain, as compared to the elastic thread alone, increased the modulus from 8.8 MPa (SD 3.7) to 17.0 MPa (SD 5.03), (p< 0.04) and significantly decreased the maximum tensile stress at breakage from 92.1N (SD 5.0) to 84.1N (SD 1.6), (p<0.004) and the tensile stress at maximum load from 107.8 N (SD 6.7) to 93.8N (SD 4.8), (p<0.002). The stress-strain curve for both groups demonstrated an initial linear behavior followed by non-linear behavior, partially obeying Hooke’s Law, due to the inherent nature of the elastic thread. The addition of the gold chain introduced a rigid element by reducing the of length of the elastic thread by one-half, altering the properties of the assembly. Conclusions: The modulus of elasticity (stiffness) increases and the toughness and resiliency decreases when a gold chain is added to the assembly and compared to elastic thread alone. This could indicate that in the gold chain group, more initial force/strain is delivered to the tooth and there is less stress relaxation over time due to the decrease in the amount of elastic thread. Therefore, the elastic thread alone delivers a more constant and continuous force to the tooth. The use of elastic thread alone may provide a biomechanically more efficient approach to orthodontic movement of impacted and open exposed teeth.
Temple University--Theses

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This thesis addresses the problem that there is no coherent, unifying paradigm for understanding the origins of homeland security threats. In addition, the thesis asks if the concept of disorder as understood in the dynamics of open, dissipative systems can provide a way of understanding real-world homeland security threats. Ideas from approaches to complex systems based on the idea of dissipative systems were synthesized to create a scalable model of a living social system that imports and exports disorder (entropy) via the transfer of matter, energy, and information. Then, the idea of a dissipative system that exports disorder to its surroundings as it self-organizes was meta-theoretically applied to the processes of self-organization occurring in the world, such as technological advance, population growth, economic growth, and globalization, and can be causally linked to real-world homeland security threats. One conclusion is that, on a descriptive level, the causes of homeland security threats can be modeled as a complex, dissipative system. Another conclusion is that causes of homeland security threats and the means to counter them often lie in complex social, economic, and environmental processes that are well outside the jurisdiction of Department of Homeland Security and the homeland security enterprise, meaning that we should reconsider our approach to homeland security.

Over the past decade, the Advanced Persistent Threat (APT) has risen to forefront of cybersecurity threats. APTs are a major contributor to the billions of dollars lost by corporations around the world annually. The threat is significant enough that the Navy Cyber Power 2020 plan identified them as a “must mitigate” threat in order to ensure the security of its warfighting network.

Reports, white papers, and various other open source materials offer a plethora of information to cybersecurity professionals regarding these APT attacks and the organizations behind them but mining and correlating information out of these various sources needs the support of standardized language and a common understand of terms that comes from an accepted APT ontology.

This paper and its related research applies the science of Natural Language Processing Open Source Intelligence in order to build an open source Ontology in the APT domain with the goal of building a dictionary and taxonomy for this complex domain.

IoT industry is growing at a rapid pace since everyone wants to connect everything to internet in order to use various services and applications using shared data. Openness is observed as an emerging trend in IoT industry. Security & privacy of the data are very important aspects in the design and deployment of the connected devices or Internet of Things. Fast growth in number of connected devices, heterogeneity, constrained resources, privacy, software upgrades and operational environment create important security related challenges in this domain. It is difficult to address challenges even with the considerable amount of existing work that has been done for decades in the area of security & privacy. In this research, a semi-systematic literature survey of the state of the art is conducted related to security & privacy aspects within the IoT area. The results were validated by conducting qualitative survey with IoT practitioners. The efforts have resulted towards identifying several security trends & challenges and security design aspects that can be considered by IoT practitioners in order to design an open and secure IoT system.It can be concluded from the study that security is not only needed but is a mandatory characteristic for IoT. However, there are no general guidelines that can be proposed to address security issues since security is not only a technical problem but is more of an awareness, mindset, people and process issue. In this thesis, a novel model is proposed with openness and security characteristics. This model is grounded based on the theoretical findings and empirical data obtained from IoT practitioners. Each of the characteristics has its own design aspects that needs to be considered by IoT practitioners to design a more secure IoT system.

This report describes the governing equation and boundary conditions for a marine propeller operating in a uniform flow field of inviscid and irrotational fluid. A method is presented by which the velocity and pressure on the blade surface of the propeller can be numerically simulated, using hyperboloidal, constant strength source and doublet panels. Accuracy of the numerical method is verified through comparison with analytically known results and the ability of the numerical simulation to predict the thrust and torque on a propeller in open water is assessed through comparison with published experimental results. The thrust and torque results for the propeller are near the experimental measurements but do not converge to a common value as the panel size decreases.

The events of 9-11 resulted in a slew of policy, procedural, and organizational changes within many government departments as the U.S. government took many steps to enhance security to prevent future terrorist attacks. The emphasis on high threat targets by the Department of Homeland Security (DHS) and other government agencies, such as the White House, the Capitol and Congressional office buildings, major infrastructure and facilities within US cities, airline travel, ports and economic supply chains has generated a great deal of debate and attention. There are however, targets that are considered low risk situated in high threat areas that also provide open access to the public for which security professionals are responsible that should not be overlooked during the War on Terror. The question is how low risk targets in high threat areas should be protected? What resource distribution makes sense? What practices should be applied to achieve security? The purpose of this research is to look at one of these targets, the Smithsonian Institution and how the Smithsonian Institution's Office of Protection Services (SI OPS) responded to the terror attacks of 9-11 and the ongoing threat. Four factors will be examined: (1) the screening process, (2) the budget, (3) the security policy formulation process, and (4) training. The study focus is based on data derived from semi-structured interviews and a review of SI documents. Examining post 9-11 security changes allows one to see how SI OPS has evolved in its attempt to meet both internal security demands and expectations against an external security concern. The findings reveal SI OPS initially underwent significant changes within the four factors in the three years following the attacks of 9-11. However, limited resources and manpower strains have played major roles in the subsequent decline in some of the factors after their initial increases. Although a return to the security levels immediately following 9-11 may not be imminent, it is recommended that OPS management make stronger efforts to communicate with non-security managers and return to more stringent visitor screening procedures.
Ph. D.

Dissertação para obtenção do Grau de Mestre em Engenharia Informática
Domain Specific Modeling (DSM) is a methodology to provide programs or system’s specification at higher level of abstraction, making use of domain concepts instead of low level programming details. To support this approach, we need to have enough expressive power in terms of those domain concepts, which means that we need to develop new languages , usually termed Domain Specific Languages (DSLs). An approach to execute specifications developed using DSLs goes by applying a model transformation technique to produce a specification in another language. These transformation techniques are applied sucessively until the specification reaches a language with an implemented run-time. The language named Concurrent Object-Oriented Petri Nets (CO-OPN) is being used successfully as a target language for such model transformation techniques. CO-OPN is an object-oriented formal language for specifying concurrent systems, that separates coordination from computational tasks. CO-OPN offers mechanisms to define the system structure and behavior, and like DSLs, relieves the developer from stipulate how that structure and behavior are attained by the underlying system. The currently available code generator for CO-OPN only produces sequential code, despite of this language potential of expressing specifications rich in concurrent behavior. The generated sequential code can be executed either in a Sequential Run-Time or in the step simulator, which is part of CO-OPN Builder IDE. The generation of sequential code turns out to be an adversity to CO-OPN application since concurrent specifications cannot be executed in parallel and therefore this languages potential is not fully exploited. This dissertation aims at filling this CO-OPN’s execution gap, through the development of a Parallel Run-Time. The new Run-Time is achieved through the adaptation of the sequential code generator and actual execution support mechanisms. In this manner, all concurrent specifications that target CO-OPN benefit from thread safe code, ready for execution in parallel and distributed environments, relieving the developer from delving into parallel programming details.By guaranteeing a safe execution environment, CO-OPN becomes an alternative to the way parallel software is nowadays developed.

Identification of a person suspected of a heinous crime before being charged risks prejudicing a fair trial. Present laws place this type of publicity outside the reach of sub judice contempt. This thesis argues there should be a change in the law of sub judice contempt making it an offence for the media to publish the fact that a person is under investigation until the person has been charged.

Identification of a person suspected of a heinous crime before being charged risks prejudicing a fair trial. Present laws place this type of publicity outside the reach of sub judice contempt. This thesis argues there should be a change in the law of sub judice contempt making it an offence for the media to publish the fact that a person is under investigation until the person has been charged.

Secure web gateways aim to protect end user systems against web based threats. Many proprietary commercial systems exist. However, their mechanisms of operation are not generally publicly known. This project undertook development and evaluation of an open source and standards based secure web gateway. The proof of concept system developed uses a combination of open source software (including the Greasyspoon ICAP Server, Squid HTTP proxy, and Clam Antivirus) and Java modules installed on the ICAP server to perform various security tasks that range from simple (such as passive content insertion) to more advanced (such as active content alteration). The makeup of the proof of concept system and the evaluation methodology for both effectiveness and performance are discussed. The effectiveness was tested using comparative analysis of groups of self-browsing high interaction client honey pots (employing a variety of security measures) and recording different system alteration rates. Performance was tested across a wide range of variables to determine the failure conditions and optimal set up for the components used. The system developed met the majority of the goals set, and results from testing indicate that there was an improvement in infection rates over unprotected systems. Performance levels attained were suitable for small scale deployments, but optimization is necessary for larger scale deployments.

Advances in medical technology have altered the need for certain types of surgery to be performed in traditional inpatient hospital settings. Less invasive surgical procedures allow a growing number of medical treatments to take place on an outpatient basis. Hospitals face growing competition from ambulatory surgery centers (ASCs). The competitive threats posed by ASCs are important, given that inpatient surgery has been the cornerstone of hospital services for over a century. Additional research is needed to understand how surgical volume shifts between and within acute care general hospitals (ACGHs) and ASCs. This study investigates how medical technology within the hospital industry is changing medical services delivery. The main purposes of this study are to (1) test Clayton M. Christensen’s theory of disruptive innovation in health care, and (2) examine the effects of disruptive innovation on appendectomy, cholecystectomy, and bariatric surgery (ACBS) utilization. Disruptive innovation theory contends that advanced technology combined with innovative business models—located outside of traditional product markets or delivery systems—will produce simplified, quality products and services at lower costs with broader accessibility. Consequently, new markets will emerge, and conventional industry leaders will experience a loss of market share to “non-traditional” new entrants into the marketplace. The underlying assumption of this work is that ASCs (innovative business models) have adopted laparoscopy (innovative technology) and their unification has initiated disruptive innovation within the hospital industry. The disruptive effects have spawned shifts in surgical volumes from open to laparoscopic procedures, from inpatient to ambulatory settings, and from hospitals to ASCs. The research hypothesizes that: (1) there will be larger increases in the percentage of laparoscopic ACBS performed than open ACBS procedures; (2) ambulatory ACBS will experience larger percent increases than inpatient ACBS procedures; and (3) ASCs will experience larger percent increases than ACGHs. The study tracks the utilization of open, laparoscopic, inpatient and ambulatory ACBS. The research questions that guide the inquiry are: 1. How has ACBS utilization changed over this time? 2. Do ACGHs and ASCs differ in the utilization of ACBS? 3. How do states differ in the utilization of ACBS? 4. Do study findings support disruptive innovation theory in the hospital industry? The quantitative study employs a panel design using hospital discharge data from 2004 and 2009. The unit of analysis is the facility. The sampling frame is comprised of ACGHs and ASCs in Florida and Wisconsin. The study employs exploratory and confirmatory data analysis. This work finds that disruptive innovation theory is an effective model for assessing the hospital industry. The model provides a useful framework for analyzing the interplay between ACGHs and ASCs. While study findings did not support the stated hypotheses, the impact of government interventions into the competitive marketplace supports the claims of disruptive innovation theory. Regulations that intervened in the hospital industry facilitated interactions between ASCs and ACGHs, reducing the number of ASCs performing ACBS and altering the trajectory of ACBS volume by shifting surgeries from ASCs to ACGHs.

碩士
國立成功大學
工程科學系碩博士班
95
Home networks are becoming increasingly popular. Open Service Gateway initiative (OSGi) platforms are a solution for integrating heterogeneous devices and e-services in home networks. In this thesis, it was found out that e-services running on an OSGi platform can not be fully protected, so a method to solve this problem is proposed. Based on Java security mechanisms, OSGi does not have its own intrusion detection system, resulting in weak protection from potential threats. Three types of threats, including shared object attacks, denial of service attacks, and abuse of legitimate e-service attacks, were simulated. All of these attacks are likely for commercial products and can successfully crash the system or steal information. To improve the security of OSGi, an Advanced OSGi Security Layer (AOSL) with detectors is proposed to solve the problems identified on OSGi platforms. The performance results show that AOSL can provide a more stable and secure execution environment for e-services, although it makes the execution time 14% to 135% slower than an unmodified OSGi platform.

碩士
輔仁大學
經濟學研究所
97
This paper makes extension of Shieh et al. (2007) to a small open economy and examines the impact of foreign military threat on domestic economic growth rate under the assumptions concerning perfect and imperfect world capital market. The findings are: under the perfect world capital market assumption, foreign military threat has no effect on domestic economic growth rate. This result greatly contrasts with the result in Shieh et al. (2007); however, under the imperfect world capital market assumption, the impact of foreign military threat depends on whether the coefficient of relative risk aversion is greater than 1. Precisely speaking, when the coefficient of relative risk aversion is greater (smaller) than 1, a rise in foreign military threat would raise (reduce) domestic economic growth rate. This result is compatible with the result in Shieh et al. (2007).

Tese de mestrado em Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2020
As ameaças cibernéticas atuais utilizam múltiplos meios de propagação, tais como a engenharia social, vulnerabilidades de e-mail e aplicações e, muitas vezes, operam em diferentes fases, tais como o comprometimento de um único dispositivo, o movimento lateral na rede e a exfiltração de dados. Estas ameaças são complexas e dependem de táticas bem avançadas, por forma a passarem despercebidas nas defesas de segurança tradicionais, como por exemplo firewalls. Um tipo de ameaças que tem tido um impacto significativo na ascensão do cibercrime são as ameaças persistentes avançadas (APTs), as quais têm objetivos claros, são altamente organizadas, têm acesso a recursos praticamente ilimitados e tendem a realizar ataques ocultos por longos períodos e com múltiplas tentativas. À medida que as organizações têm tido consciência que os ciberataques estão a aumentar em quantidade e complexidade, a utilização de informação sobre ciberameaças está a ganhar popularidade para combater tais ataques. Esta tendência tem acompanhado a evolução das APTs, uma vez que estas exigem um nível de resposta diferente e mais específico a cada organização. A informação sobre ciberameaças pode ser obtida de diversas fontes e em diferentes formatos, sendo a informação de fonte aberta (OSINT) uma das mais comuns. Também pode ser obtida por plataformas especificas de ameaças (TIPs) que ajudam a consumir, produzir e partilhar informações sobre ciberameaças. As TIPs têm múltiplas vantagens que permitem às organizações explorar facilmente os principais processos de recolha, enriquecimento e partilha de informações relacionadas com ameaças. No entanto, devido ao elevado volume de informação OSINT recebido por dia e às diversas taxonomias existentes para classificação de ciberameaças provenientes do OSINT, as TIPs atuais apresentam limitações de processamento desta, capaz de produzir informação inteligente (threat intelligence, TI) de qualidade que seja útil no combate de ciberataques, impedido assim a sua adoção em massa. Por sua vez, os analistas de segurança desperdiçam um tempo considerável em analisar o OSINT e a classificá-lo com diferentes taxonomias, por vezes, correspondentes a ameaças da mesma categoria. Esta dissertação propõe uma solução, denominada Automated Event Classification and Correlation Platform (AECCP), para algumas das limitações das TIPs mencionadas anteriormente e relacionadas com a gestão do conhecimento de ameaças, a triagem de ameaças, o elevado volume de informação partilhada, a qualidade dos dados, as capacidades de análise avançadas e a automatização de tarefas. Esta solução procura aumentar a qualidade da TI produzidas por TIPs, classificando-a em conformidade com um sistema de classificação comum, removendo a informação irrelevante, ou seja, com baixo valor, enriquecendo-a com dados importantes e relevantes de fontes OSINT, e agregando-a em eventos com informação semelhante. O sistema de classificação comum, denominado de Unified Taxonomy, foi definido no âmbito desta dissertação e teve como base uma análise de outras taxonomias públicas conhecidas e utilizadas na partilha de TI. O AECCP é uma plataforma composta por componentes que podem trabalhar em conjunto ou individualmente. O AECCP compreende um classificador (Classifier), um redutor de informação irrelevante (Trimmer), um enriquecedor de informação baseado em OSINT (Enricher) e um agregador de agregador de eventos sobre a mesma ameaça, ou seja, que contêm informação semelhante (Clusterer). O Classifier analisa eventos e, com base na sua informação, classifica-os na Unified Taxonomy, por forma a catalogar eventos ainda não classificados e a eliminar a duplicação de taxonomias com o mesmo significado de eventos previamente classificados. O Trimmer elimina a informação menos pertinente dos eventos baseando-se na classificação do mesmo. O Enricher enriquece os eventos com dados externos e provenientes de OSINT, os quais poderão conter informação importante e relacionada com a informação já presente no evento, mas não contida no mesmo. Por último, o Clusterer agrega eventos que partilham o mesmo contexto associado à classificação de cada um e à informação que estes contêm, produzindo aglomerados de eventos que serão combinados num único evento. Esta nova informação garantirá aos analistas de segurança o acesso e fácil visibilidade a informação relativa a eventos semelhantes aos que estes analisam. O desenho da arquitetura do AECCP, foi fundamentado numa realizada sobre três fontes públicas de informação que continham mais de 1100 eventos de ameaças de cibersegurança partilhados por 24 entidades externas e colecradas entre os anos de 2016 e 2019. A Unified Taxonomy utilizada pelo Classifier, foi produzida com base na análise detalhada das taxonomias utilizadas por estes eventos e nas taxonomias mais utilizadas na comunidade de partilha de TI sobre ciberameaças. No decorrer desta análise foram também identificados os atributos mais pertinentes e relevantes para cada categoria da Unified Taxonomy, através da agregação da informação em grupos com contexto semelhante e de uma análise minuciosa da informação contida em cada um dos mais de 1100 eventos. A dissertação, também, apresenta os algoritmos utilizados na implementação de cada um dos componentes que compõem o AECCP, bem como a avaliação destes e da plataforma. Na avaliação foram utilizadas as mesmas três fontes de OSINT utilizadas na análise inicial, no entanto, com 64 eventos criados e partilhados mais recentemente que os utilizados nessa análise. Dos resultados, foi possível verificar um aumento de 72% na classificação dos eventos, um aumento médio de 54 atributos por evento, com uma redução nos atributos com pouco valor e aumento superior de atributos com maior valor, após os eventos serem processados pelo AECCP. Foi também possível produzir 24 eventos agregados, enriquecidos e classificados pelos outros componentes do AECCP. Por último, foram processados pelo AECCP 6 eventos com grande volume de informação produzidos por uma plataforma externa, denominada de PURE, onde foi possível verificar que o AECCP é capaz de processar eventos oriundos de outras plataformas e de tamanho elevando. Em suma, a dissertação apresenta quatro contribuições, nomeadamente, um sistema de classificação comum, a Unified Taxonomy, os atributos mais pertinentes para cada uma das categorias da Unified Taxonomy, o desenho da arquitetura do AECCP composto por 4 módulos (Classifier, Trimmer, Enricher e Clusterer) que procura resolver 5 das limitações das atuais TIPs (gestão do conhecimento de ameaças, a triagem de ameaças, o elevado volume de informação partilhada, a qualidade dos dados e as capacidades de análise avançadas e a automatização de tarefas) e a sua implementação e avaliação.
Today’s threats use multiple means of propagation, such as social engineering, email, and application vulnerabilities, and often operate in different phases, such as single device compromise, network lateral movement and data exfiltration. These complex threats rely on well-advanced tactics for appearing unknown to traditional security defences. One type that had a major impact in the rise of cybercrime are the advanced persistent threats (APTs), which have clear objectives, are highly organized and well-resourced and tend to perform long term stealthy campaigns with repeated attempts. As organizations realize that attacks are increasing in size and complexity, threat intelligence (TI) is growing in popularity and use amongst them. This trend followed the evolution of the APTs as they require a different level of response that is more specific to the organization. TI can be obtained via many formats, being open source intelligence (OSINT) one of the most common; and using threat intelligence platforms (TIPs) that aid organization consuming, producing and sharing TI. TIPs have multiple advantages that enable organisations to easily bootstrap the core processes of collecting, normalising, enriching, correlating, analysing, disseminating and sharing of threat related information. However, current TIPs have some limitations that prevents theirs mass adoption. This dissertation proposes a solution to some of these limitations related with threat knowledge management, limited technology enablement in threat triage, high volume of shared threat information, data quality and limited advanced analytics capabilities and tasks automation. Overall, our solution improves the quality of TI by classifying it accordingly a common taxonomy, removing the information with low value, enriching it with valuable information from OSINT sources, and aggregating it into clusters of events with similar information. This dissertation offers a complete data analysis of three OSINT feeds and the results that made us to design our solution, a detailed description of the architecture of our solution, its implementations and its validation, including the processing of events from other academic solutions.

Tese de mestrado, Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2019
The Impact of cyber-attacks and its cost has become a top priority for most organizations. To more aptly protect themselves, organizations are moving from reactive to proactive defensive measures, investing in cyber threat intelligence (CTI) to provide them forewarning about the risks they face, as well as to accelerate their response times in the detection of attacks. One means to obtain CTI is the collection of open source intelligence (OSINT) feeds via threat intelligence platforms and their representation as indicators of compromise (IoC). However, most of these platforms are providing threat information with little to no processing. This Situation increases the pressure on security analysts who, already faced with the arduous task of sorting through the multitude of alerts originating from their networks must also sort this additional flow of data to find relevant intelligence.This dissertation proposes an architecture to generate threat intelligence of quality in the form of new intelligence is obtained by correlating IoCs coming from different OSINT feeds that contain information on the same threat, aggregation them into clusters, and then representing the threat information contained within those clusters in a single enriched IoC. This dissertation first offers an overview of the use of CTI, methodologies, and technologies used, before proposing an architecture focused on a clustering approach, for which two methods are introduced, the naïve and the n-level aggregation. It then describes the implementation of this architecture and its validation. The proposal was implemented in a prototype confirmed with 34 OSINT feeds, which allowed the creation of enriched IoCs that may enable the identification of cyber-attacks not previously possible by analyzing the received IoCs individually.

Dissertação de Mestrado em Engenharia Electrotécnica e de Computadores
Durante o decorrer da sua história, o Homem demonstrou sempre um enorme desejo de informação. Desde o surgimento do primeiro sistema de informação, a «Fala», passando pela «Escrita», pelo «Livro», pela «Imprensa», até ao surgimento do mais revolucionário de todos, a «Internet», o ser humano procurou sempre uma partilha global da informação. As sucessivas (r)evoluções da informação mostraram ser capazes de mudar e moldar toda uma sociedade. A «Internet» não foi excepção. O aparecimento desta provou que a partilha global da informação é possível e desencadeou uma revolução de tal ordem, que apenas pode ser comparável com a grande «Revolução Industrial», trazendo até nós a denominada «Sociedade da Informação e do conhecimento». Percebendo que através de sistemas computacionais conseguiriam apresentar uma maior produtividade, as empresas começaram a aderir às redes informáticas. Actualmente é muito difícil encontrarmos empresas que não possuam infra-estruturas informáticas para suprir as suas necessidades. Esta informatização das organizações fez surgir novos conceitos, tais como o de «empresa virtual», «e-business», «home office», «e-commerce», entre outros. A informação tornou-se, cada vez mais, um activo importantíssimo das organizações capaz de gerar valor, lucros e benefícios. Porém, os computadores e a maneira como se comunicam, não servem apenas para auxiliar as empresas nos seus processos. Com os conhecimentos adequados é possível alguém aproveitar o poder computacional para executar os denominados «ataques informáticos», com os mais variados objectivos, colocando a informação em risco. Provado o enorme valor da informação para as empresas é de grande necessidade criar medidas e soluções de protecção. Esta Dissertação de Mestrado tratará do estudo de uma dessas soluções: o software de auditoria de segurança, Babel Enterprise.
During the course of history, man has always shown a great desire for information. Since the emergence of the first information system, the «speech», followed by «writing», the «book», the «press» to the emergence of the most revolutionary of all, the «Internet», man has always sought a share of the global information. Successive (r)evolutions of the information proved to be able to change and shape the whole society. The «Internet» was no exception. The emergence of this proved that the global sharing of information is possible, sparking a revolution of such order, which can only be comparable with the phenomenon of large «Industrial Revolution», bringing us up today’s society, the so-called «information society and knowledge». Realizing that through computer systems will be able to provide greater productivity, companies began to join the computer network. Today it is very difficult to find companies that lack IT infrastructure to meet their needs. This informatization of organizations gave rise to new concepts, such as «virtual enterprise», «home office», «e-business», «E-commerce», among others. The information has become an important asset of organizations to generate value, profits and benefits. However, the computers and how they communicate, exist not only to help companies in their workflow. With the appropriate knowledge somebody harness the computing power to perform the so-called «cyber attacks» with the most varied objectives, putting information at risk. Proved the huge value of the business information is of great need to create measures and protective solutions. This Master Thesis will address the study of one of these solutions. The audit networks tool, Babel Enterprise.

Conventionally the size of the back clearance played a great importance on reducing the axial clearance by utilizing the concept that the decreased axial clearance results in lower axial force acting on the impeller. However, from the previous works on the effect of the back clearance on the hydrodynamic forces upon the semi-open impeller showed the opposite trend: increasing the back clearance results in the reduced axial loading. In this work, the CFD simulation of an entire pump and detailed analysis on the back clearance flow are performed. By utilizing the commercially available software, meshing and CFD simulations are performed. LDA data, unsteady pressure data, and pressure distributions on the housing are used to validate the CFD model. The flow field prediction of the back clearance flow is then compared with other researcher’s works of the gap flow analysis between the rotating and stationary disks. The flow field inside the impeller passage, which is very sensitive to the back clearance size, is also studied. The empirical equation for the leakage loss through the balance holes is produced using the CFD predictions.

University of Technology, Sydney. Faculty of Science.
The Antarctic marine ecosystem is unique and dynamic, changing seasonally and forming specialised niche habitats including open ocean, sea ice and meltwater environments. Phytoplankton are key species in the structure and function of the Antarctic ecosystem, instrumental in the regions biogeochemistry, fundamental to the food web and strong contributors to global primary production and carbon sequestration. Understanding the photosynthetic plasticity of Antarctic phytoplankton is essential to understanding the effects global change is likely to have on primary production in the region. Through a series of experiments, this thesis explores the processes of light acclimation, photoprotection and photoinhibition in Antarctic microalgae under different environmental stressors, comparing photophysiological responses of species known to inhabit the sea-ice, meltwater and pelagic regions of Antarctic waters. The photosynthetic properties of three Antarctic diatoms (Fragilariopsis cylindrus, Pseudo-nitzschia subcurvata and Chaetoceros sp.) to changes in salinity, temperature and light were compared. Large heterogeneities in the photoprotective capacity of the three species and several distinct physiological strategies in response to the rapid changes in the ambient environment were observed (Publication I). Similarly, photosynthesis and net primary productivity was species-specific with large differences between environmental conditions (Publication II). Fast induction kinetics and pulse amplitude modulated fluorometry were used to demonstrate high levels of flexibility in light acclimation capabilities of sea ice algae from the east Antarctic. Inhibitors and pigment analyses identified xanthophyll cycling as the critical mechanism for photoprotection and preferred means by which sea ice diatoms regulated energy flow to PS1 (Publication III). While immunoblot analyses of natural communities measured minimal D1 protein breakdown in algae exposed to irradiances up to 200 µmol photons m⁻² s⁻¹. These data showed that sea ice diatoms had low intrinsic susceptibility to PSII photoinactivation and strong irradiance-dependent induction of non-photochemical quenching that was independent of protein resynthesis (Publication IV). The remaining chapters investigated photoprotective strategies and photosynthetic plasticity of phytoplankton under nutrient limitation. Nitrogen depletion in F. cylindrus had a strong influence on non-photochemical quenching capacity and resulted in the impairment of photosynthetic electron transport resulting in the formation of Qʙ non-reducing PSII centres within the photosystem (Publication V). The influence of iron-limitation and high light stress on the growth and physiology of Southern Ocean phytoplankton revealed a community-based response of measurable changes in pigment ratios, photosynthetic capacity and community composition (Publication VI). Iron-limited phytoplankton altered the allocation of photosynthetically derived energy, increasing photoprotective pigment pools and down-regulating photochemistry, at the expense of photosynthetic plasticity.

碩士
國立東華大學
體育與運動科學系
105
The purpose of this study was to discuss the accuracy and shooting average of a basketball shot; through shooting with open and closed-eyes from the free-throw-line. Subjects of the study include 10 players from each the level 1 and level 3 of Dong-Hua University who participated in the “Academic Year 99’s College League Games”. In addition, 10 players from Hualien High School who participated in the “Academic Year 99’s High-school League Games” were also measured objects. The experiment came in two stages: The subjects began shooting from the free-throw-line. Stage one starts off with 10 open-eye shots; followed by another 10 of closed-eye shots. Stage two starts off with 15 open-eye shots; followed by another 15 of closed-eye shots. There were 50 shots in total. After each shot, the researchers immediately recorded the scores and shooting average. Finally, an independent two-way ANOVA was used to analyze the accuracy of the shooting tests; while a one-way ANOVA analysis of variance was carried out to investigate the shooting average of free-throw shots. The study results showed that all three groups of subjects performed better in both accuracy and shooting average; and that the level 1 group were better than those of level 3 group and High-school group. A comparison of all three groups on their first and second closed-eye shots, we saw that the level 1 group performed better on their second try; while there were no significant distinctions between the two trials for the level 3 group and the High-school teams. On this basis, we can thus inferred that the level 1 group possesses better adaptability in the closed-eye shots test.

Introduction: Une respiration buccale est souvent associée à une faible musculature oro-faciale et à une position basse de la langue, pouvant mener aux malocclusions et au potentiel de développer des problèmes de respiration pendant le sommeil chez les enfants. Objectifs: Évaluer l’efficacité de la thérapie oro-faciale myofonctionnelle sur le rétablissement d’une déglutition physiologique et d’une respiration nasale en développant une posture linguale et labiale normale au repos. Méthodes: Cette étude contrôlée randomisée prospective à simple aveugle a évalué 37 patients (six à quatorze ans) divisés en deux groupes où un groupe a reçu une thérapie complète (7 séances), comprenant des exercices pour la correction du patron de déglutition et de la posture linguale, et l’autre groupe a reçu une thérapie sommaire, corrigeant seulement la posture linguale (3 séances). Des suivis à trois mois et à un an post-traitement ont été effectués pour les deux groupes. Résultats: Les résultats des deux traitements, soient la thérapie complète et la thérapie sommaire, sont similaires (p = 0.59) et également efficaces pour la correction de la déglutition atypique et le rétablissement d’une respiration nasale, avec une différence significative entre les évaluations avant et après traitement (p = 0.001), qui demeure stable après un an post-traitement. Conclusion: Le traitement avec des exercices spécifiques pour une correction d’une propulsion linguale ne serait pas une composante absolue d’une thérapie oro-faciale myofonctionnelle afin de rétablir une posture linguale adéquate au repos et un patron de respiration nasale chez les enfants n’ayant pas d’autre problème fonctionnel connu.
Introduction: Mouth breathing is often associated with a weak orofacial musculature and a low resting tongue position, leading to malocclusion and potentially sleep-disordered breathing in children. Objective: To evaluate the effect of orofacial myofunctional therapy on the reestablishment of a mature pattern of swallowing and nasal breathing by stabilizing a proper position of the tongue and lips at rest. Methods: This prospective randomized single-blind controlled study evaluated 37 patients (age six to fourteen years) divided into two groups who received either a complete orofacial myofunctional therapy (7 sessions) including swallowing pattern and tongue posture, or a simplified therapy modifying their tongue posture (3 sessions). Both groups were seen at three months and one year following treatment completion. Results: Results suggested that treatment outcomes were similar when treating tongue-lip posture at rest along with tongue thrust, and treating without addressing tongue thrust (p = 0.59). Both treatments were efficacious as there was a significant difference between the pre- and post- evaluations for both groups (p < 0.001), and these differences remained stable at the one year follow-up. Conclusion: Treating a tongue thrust habit with specific related exercises, may not be a necessary component of an orofacial myofunctional therapy to reestablish tongue posture at rest and nasal breathing in children with no other functional problems.