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Bioinformatic analysis of fruit-specific expressed sequence tag libraries of Diospyros kaki Thunb.: view at the transcriptome at different developmental stages
No full textWe present here a systematic analysis of the Diospyros kaki expressed sequence tags (ESTs) generated from development stage-specific libraries. A total of 2,529 putative tentative unigenes were identified in the MF library whereas the OYF library displayed 3,775 tentative unigenes. Among the two cDNA libraries, 325 EST-Simple sequence repeats (SSRs) in 296 putative unigenes were detected in the MF library showing an occurrence of 11.7% with a frequency of 1 SSR/3.16 kb whereas the OYF library had an EST-SSRs occurrence of 10.8% with 407 EST-SSRs in the 352 putative unigenes with a frequency of 1 SSR/2.92 kb. We observed a higher frequency of SNPs and indels in the OYF library (20.94 SNPs/indels per 100 bp) in comparison to MF library showed a relatively lower frequency (0.74 SNPs/indels per 100 bp). A combined homology and secondary structure analysis approach identified a potential miRNA precursor, an ortholog of miR159, and potential miR159 targets, in the development-specific ESTs of D. kak
Acquiring volatile operating system data tools and techniques
No full textThe current approach to forensic examination during search and seizure has predominantly been to pull the plug on the suspect machine and subsequently perform a post mortem examination on the storage medium. However, with the advent of larger capacities of memory, drive encryption and anti-forensics, this procedure may result in the loss of valuable evidence. Volatile data may be vital in determining criminal activity; it may contain passwords used for encryption, indications of anti-forensic techniques, memory resident malware which would otherwise go unnoticed by the investigator. This paper emphasizes the importance of understanding the potential value of volatile data and how best to collate forensic artifacts to the benefit of the investigation, ensuring the preservation and integrity of the evidence. The paper will review current methods for volatile data collection, assessing the capabilities, limitations and liabilities of current tools and techniques available to the forensic investigator
The record producer as nexus: creative inspiration, technology and the recording industry
No full textWhat is a record producer? There is a degree of mystery and uncertainty about just what goes on behind the studio door. Some producers are seen as Svengali-like figures manipulating artists into mass consumer product. Producers are sometimes seen as mere technicians whose job is simply to set up a few microphones and press the record button. Close examination of the recording process will show how far this is from a complete picture. Artists are special—they come with an inspiration, and a talent, but also with a variety of complications, and in many ways a recording studio can seem the least likely place for creative expression and for an affective performance to happen. The task of the record producer is to engage with these artists and their songs and turn these potentials into form through the technology of the recording studio. The purpose of the exercise is to disseminate this fixed form to an imagined audience—generally in the hope that this audience will prove to be real. Finding an audience is the role of the record company. A record producer must also engage with the commercial expectations of the interests that underwrite a recording.This dissertation considers three fields of interest in the recording process: the performer and the song; the technology of the recording context; and the commercial ambitions of the record company—and positions the record producer as a nexus at the interface of all three. The author reports his structured recollection of five recordings, with three different artists, that all achieved substantial commercial success. The processes are considered from the author‘s perspective as the record producer, and from inception of the project to completion of the recorded work. What were the processes of engagement? Do the actions reported conform to the template of nexus? This dissertation proposes that in all recordings the function of producer/nexus is present and necessary—it exists in the interaction of the artistry and the technology.ivThe art of record production is to engage with these artists and the songs they bring and turn these potentials into form
On the (un-)decidability of model-checking resource-bounded agents
No full textThe verification and modelling of multi-agent systems is an important topic that has attracted much attention in recent years. Resources, however, have only recently been studied as simple extensions to well-known logics. Trying to find a set of useful features while retaining essential properties for practical use, we explore the question: Where are the limits of what can be verified about resource-bounded agents? We try to answer this question by considering several natural logic-based settings that may arise and prove that verification is usually undecidable apart from bounded or otherwise restrictive settings. Most interestingly, we identify various factors that influence the (un-)decidability and provide grounds for future research on more promising constraints leading to decidable fragments
Discrete event calculus using Semantic Web technologies
Get PDFThis thesis provides a detailed description of the research undertaken into the creation of a framework that uses Semantic Web languages to implement a recently developed commonsense reasoning formalism called Discrete Event Calculus (DEC). It aims to show to what extent DEC reasoning can be applied to Semantic Web data, using the Semantic Web standards and supporting development environments available for the purpose in 2008, when the research programme commenced.The research aims to provide an accurate and reusable DEC ontology using the languages defined in Semantic Web Standards. To this end, an ontology describing the DEC entities and axioms is defined in OWL and SWRL; this represents the core elements of the DEC formalism, namely its set of logical types and predicates and the relations between them. The ontology is used together with a proof-of-concept DEC resolver software that applies the ontology to an existing rules engine, so that new inferences can be created from a DEC domain. The design and implementation of the combined ontology and software framework are described in detail.
The methodological issues involved in reconciling a software model with an ontology model are also discussed and the capabilities of the framework are validated by a series of tests modelled on established AI benchmark scenarios that can be resolved correctly using DEC. The results confirm that the framework will create the appropriate inferences with reference to the benchmark problems, though they also highlight some of current limitations in the framework, notably to do with how it represents changing fluent values.A detailed sample domain ontology is provided, which is based on the domain of turn-based multiplayer online games; this illustrates how the DEC ontology defined in this research could be extended for use with other domains. A further extension of the DEC ontology is proposed, which enables the resolver to represent real-world time values independently of the timepoints defined as part of the formalism.Finally, the strengths and extant boundaries of the chosen approach are discussed and suggestions are provided for improvements that could form the basis of future work
Applications of perfect difference codes in fiber-optics and wireless optical code-division multiplexing/multiple-access systems
Get PDFAfter establishing itself in the radio domain, Spread spectrum code-division
multiplexing/multiple-access (CDMA) has seen a recent upsurge in optical
domain as well. Due to its fairness, flexibility, service differentiation and
increased inherent security, CDMA is proved to be more suitable for the bursty
nature of local area networks than synchronous multiplexing techniques like
Frequency/Wavelength Division Multiplexing (F/WDM) and Time Division
Multiplexing (TDM). In optical domain, CDMA techniques are commonly known
as Optical-CDMA (O-CDMA). All optical CDMA systems are plagued with the
problem of multiple-access interference (MAI). Spectral amplitude coding (SAC)
is one of the techniques used in the literature to deal with the problem of MAI.
The choice of spreading code in any CDMA system is another way to ensure the
successful recovery of data at the receiving end by minimizing the effect of MAI
and it also dictates the hardware design of the encoder and decoder.
This thesis focuses on the efficient design of encoding and decoding hardware.
Perfect difference codes (PDC) are chosen as spreading sequences due to their
good correlation properties. In most of the literature, evaluation of error
probability is based on the assumptions of ideal conditions. Such assumptions
ignore major physical impairments such as power splitting losses at the
multiplexers of transmitters and receivers, and gain losses at the receivers, which
may in practice be an overestimate or underestimate of the actual probability of
error.
This thesis aims to investigate thoroughly with the consideration of practical
impairments the applications of PDCs and other spreading sequences in optical
communications systems based on spectral-amplitude coding and utilizing codedivision
as multiplexing/multiple-access technique. This work begins with a
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general review of optical CDMA systems. An open-ended practical approach has
been used to evaluate the actual error probabilities of OCDM/A systems under
study. It has been concluded from results that mismatches in the gains of
photodetectors, namely avalanche photodiode (APDs), used at the receiver side
and uniformity loss in the optical splitters results in the inaccurate calculation of
threshold level used to detect the data and can seriously degrade the system bit
error rate (BER) performance. This variation in the threshold level can be
compensated by employing techniques which maintain a constant interference
level so that the decoding architecture does not have to estimate MAI every time
to make a data bit decision or by the use of balanced sequences.
In this thesis, as a solution to the above problem, a novel encoding and decoding
architecture is presented for perfect difference codes based on common zero code
technique which maintains a constant interference level at all instants in CDM
system and thus relieves the need of estimating interference. The proposed
architecture only uses single multiplexer at the transmitters for all users in the
system and a simple correlation based receiver for each user. The proposed
configuration not only preserves the ability of MAI in Spectral-Amplitude Coding
SAC-OCDM system, but also results in a low cost system with reduced
complexity. The results show that by using PDCs in such system, the influence of
MAI caused by other users can be reduced, and the number of active users can be
increased significantly.
Also a family of novel spreading sequences are constructed called Manchestercoded
Modified Legendre codes (MCMLCs) suitable for SAC based OCDM
systems. MCMLCs are designed to be used for both single-rate and Multirate
systems. First the construction of MCMLCs is presented and then the bit error rate
performance is analyzed.
Finally the proposed encoding/decoding architecture utilizing perfect difference
codes is applied in wireless infrared environment and the performance is found to
be superior to other codes
A blended learning model in higher education: a comparative study of blended learning in UK and Malaysia
Get PDFBlended learning, involves the combination of two fields of concern: technology and education; or two groups of people: technologists and educationists. However, current literature shows less consideration on the potential disciplinary gap in the blended learning experience, as a result there is a paucity of evidence from cross-country/institutional/disciplinary investigations. This study aimed to explore, analyse and compare the blended learning experience in higher education. The research is reflected in 3 questions: (1) What are the current blended learning experiences in the selected higher educational institutions? (2) How such experience varies in different disciplines? (3) What are the reflections on the comparative experiences in (1) and (2)? The qualitative case study with comparative methods was used to obtain in-depth findings for these research questions. I visited 4 universities in two countries and sampled 51 research participants’ voices from contrasting disciplines. With these voices, I thoroughly discussed individual case studies, followed by a cross-case and cross-discipline comparison. These findings enabled insights to be drawn on a major argument: blended learning did enable and enhance learning experiences in all case studies but disciplinary differences remain a major challenge. The analysis shows that academics from science-based disciplines have an advantage at the instrumental level of technological usage without transforming learning experience; social science-based academics, due to their disciplinary nature, have embedded technology in wider trans-technical aspects that would enhance and transform learning and teaching. In the context of blended learning, I would argue that learning has not been enhanced (1) if the technology is the sole focus; (2) if the research effort of “technology enhanced learning” does not gain ground in educational theories and (3) does not recognise the disciplinary differences. Arising out of these findings, I proposed a blended learning model that indicates the boundary of the current literature and research findings, and a blended learning definition - an educational-focused process to enhance and transform f2f learning with the blend of technology in a symbiotic relationship. It is necessary for educationists and technologists to establish such a symbiotic relationship and the inter-disciplinary integration and discourse, that may impact on the individuals’ practice beyond their own disciplinary territory
3D imaging in forensic odontology
No full textThis work describes the investigation of a new 3D capture method for acquisition and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras, errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded in a 2D space. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors.
The proposed solutions in this work are: conducting a review of the current 2D and three 3D capture methods, also a series of benchmarks for system assessment. Followed by a series of performance evaluations of the existing current 2D and two 3D methods. Further proposed solutions include, the design of a system specification for the practical reproducible acquisition of bite mark injuries. Finally a review of the validation process for forensic evidence presented to the courts.
The results of the work are as follows: A 3D system is required to produce the correct 3D data of a bite mark and suspect dentition for forensic analysis. Such a system should be practical and consistent, if it is to replace the current de facto 2D systems. The MAVIS hardware can be considered a practical and consistent solution for producing the required 3D image of a bite mark for analysis; however, the MAVIS hardware cannot produce a satisfactory 3D image of a dental cast. At present a laser scanner is required to produce satisfactory results of a dental cast. Angular distortion and errors created by the user in 2D image capture can hinder the digital measurement process. 3D capture therefore introduces less operator error in the form of angular distortion
Undead radio: zombies and the living dead on 1930s to 1940s US radio
No full textThe zombie is ubiquitous in popular culture: from comic books to video games, to internet applications and homemade films, zombies are all around us. Investigating the zombie from an interdisciplinary perspective, with an emphasis on deep analytical engagement with diverse kinds of texts, Better Off Dead addresses some of the more unlikely venues where zombies are found while providing the reader with a classic overview of the zombie's folkloric and cinematic history.What has the zombie metaphor meant in the past? Why does it continue to be so prevalent in our culture? Where others have looked at the zombie as an allegory for humanity's inner machinations or claimed the zombie as capitalist critique, this collection seeks to provide an archaeology of the zombie-tracing its lineage from Haiti, mapping its various cultural transformations, and suggesting the post-humanist direction in which the zombie is ultimately heading.Approaching the zombie from many different points of view, the contributors look across history and across media. Though they represent various theoretical perspectives, the whole makes a cohesive argument: The zombie has not just evolved within narratives; it has evolved in a way that transforms narrative. Hand’s chapter looks at radio zombies
Near real-time threat assessment using intrusion detection system's data
No full textThe concept of Intrusion Detection (ID) and the development of such systems
have been a major concern for scientists since the late sixties. In recent computer
networks, the use of different types of Intrusion Detection Systems (IDS) is
considered essential and in most cases mandatory. Major improvements have been
achieved over the years and a large number of different approaches have been
developed and applied in the way these systems perform Intrusion Detection.
The purpose of the research is to introduce a novel approach that will enable us to
take advantage of the vast amounts of information generated by the large number of
different IDSs, in order to identify suspicious traffic, malicious intentions and
network attacks in an automated manner. In order to achieve this, the research focuses
upon a system capable of identifying malicious activity in near real-time, that is
capable of identifying attacks while they are progressing. The thesis addresses the
near real-time threat assessment by researching into current state of the art solutions.
Based on the literature review, current Intrusion Detection technologies lean towards event correlation systems using different types of detections techniques. Instead of
using linear event signatures or rule sets, the thesis suggests a structured description
of network attacks based on the abstracted form of the attacker’s activity. For that
reason, the design focuses upon the description of network attacks using the
development of footprints. Despite the level of knowledge, capabilities and resources
of the attacker, the system compares occurring network events against predefined
footprints in order to identify potential malicious activity. Furthermore, based on the
implementation of the footprints, the research also focuses upon the design of the
Threat Assessment Engine (TAE) which is capable of performing detection in near
real-time by the use of the above described footprints. The outcome of the research proves that it is possible to have an automated
process performing threat assessment despite the number of different ongoing attacks
taking place simultaneously. The threat assessment process, taking into consideration
the system’s architecture, is capable of acting as the human analyst would do when
investigating such network activity. This automation speeds up the time-consuming
process of manually analysing and comparing data logs deriving from heterogeneous sources, as it performs the task in near real-time. Effectively, by performing the this
task in near real-time, the proposed system is capable of detecting complicated
malicious activity which in other cases, as currently performed, it would be difficult,
maybe impossible or results would be generated too late