Analysis of Hand Segmentation in the Wild

A large number of works in egocentric vision have concentrated on action and object recognition. Detection and segmentation of hands in first-person videos, however, has less been explored. For many applications in this domain, it is necessary to accurately segment not only hands of the camera wearer but also the hands of others with whom he is interacting. Here, we take an in-depth look at the hand segmentation problem. In the quest for robust hand segmentation methods, we evaluated the performance of the state of the art semantic segmentation methods, off the shelf and fine-tuned, on existing datasets. We fine-tune RefineNet, a leading semantic segmentation method, for hand segmentation and find that it does much better than the best contenders. Existing hand segmentation datasets are collected in the laboratory settings. To overcome this limitation, we contribute by collecting two new datasets: a) EgoYouTubeHands including egocentric videos containing hands in the wild, and b) HandOverFace to analyze the performance of our models in presence of similar appearance occlusions. We further explore whether conditional random fields can help refine generated hand segmentations. To demonstrate the benefit of accurate hand maps, we train a CNN for hand-based activity recognition and achieve higher accuracy when a CNN was trained using hand maps produced by the fine-tuned RefineNet. Finally, we annotate a subset of the EgoHands dataset for fine-grained action recognition and show that an accuracy of 58.6% can be achieved by just looking at a single hand pose which is much better than the chance level (12.5%).Comment: Accepted at CVPR 201

An Error Analysis of the Use of Lexical Collocations in the Academic Writing of Libyan EFL University Students

The main aim of this paper is to explore the difficulties Libyan undergraduate university English major students have in the use of verb-noun and adjective-noun collocations by looking at their performance in free production. Furthermore, twelve verbs and twelve adjectives[1] identified in this research were investigated in depth as part of their combinations. To achieve the main aim, a 250-word academic writing task was used to collect data from fourth-year university students at Tripoli University (the Department of English). The data was analysed using AntConc 3.2.1w (Anthony, 2007). After extracting the learners’ collocations, four methods were used to determine and judge the acceptability of learners’ collocations in terms of conforming to native-like use. They are: (1) the OCD (2009), (2) the online British National Corpus (3) consultations with two native speakers, and (4) the acceptability-of-collocations survey was used to triangulate the above three methods Findings from the academic writing data reveal that: (1) three broad categories of errors were identified in the erroneously produced verb-noun and adjective-noun collocations in the LLC: (i) grammatical errors, (ii) lexical errors and (iii) errors related to usage; and (2)  Furthermore, these categories were classified into sixteen and twelve error types in verb-noun and adjective-noun collocations respectively such as wrong choice of verb, wrong choice of adjective, wrong choice of noun, determiner errors, preposition errors, number errors, wrong word order errors, word form errors, usage category errors, intensifier errors and wrong register errors. [1] The twelve verbs are do, provide, acquire, gain, enhance, make, offer, take, give, get, have and require. The twelve adjectives are good, academic, high, higher, modern, current, practical, specific, basic, general, great and special

Synthesis and characterisation of imprinted polymeric receptor mimics

Molecularly imprinted polymers (MIPs) are crosslinked polymers containing bespoke functionalised cavities arising from the inclusion of template molecules in the polymerisation mixture and their later extraction. When the polymers are prepared functional polymerisable monomers are included which become part of the polymer matrix and serve to decorate the cavities with functionality appropriate to the template molecules. Overall, binding sites are created which have a memory for the template both in terms of shape and matching functionality. Fluorescent molecularly imprinted polymers have the benefit of a fluorophore in their cavities that may respond to the presence of bound test compound by a change in their fluorescence output. The work presented falls into three main areas. A series of fluorescent MIPs was prepared with a view to generating material capable of mimicking the binding characteristics of the metabolically important cytochrome isoform CYP2D6. The MIPs re-bound their templates and various cross-reactivities were encountered for test compound/drug recognition. One MIP in particular exhibited a rational discrimination amongst the related synthetic templates and was reasonably successful in recognising CYP2D6 substrates from the drug set tested. In order to give some insights into binding modes in MIPs, attempts were made to produce functional monomers containing two or more fluorophores that could be interrogated independently. A model compound was prepared which fitted the dual-fluorophore criteria and which will be the basis for future incorporation into MIPs. A further strand to this thesis is the deliberate incorporation of hydrophobic moieties into fluorescent functional monomers so that the resulting imprinted cavities might be biomimetic in their impersonation of enzyme active sites. Thus the imprinted cavities had specific hydrophobic regions as well as the usual polar functionality with which to interact with binding test compounds

Assessing Collocational Competence: Insights Derived from Libyan Learners of English in an EFL Context

This paper aims to investigate the difficulties Libyan undergraduate university English major students have in the use of verb-noun and adjective-noun collocations by looking at their performance in free production. Furthermore, twelve verbs and twelve adjectives identified in this research were investigated in depth as part of their combinations. To achieve this aim, a 250-word academic writing task was used to collect data from fourth-year university students at Tripoli University. The data were analysed using AntConc 3.2.1w (Anthony, 2007). After extracting the learners’ collocations, four methods were used to determine the acceptability of learners’ collocations in terms of conforming to native-like use. They were: (1) the Oxford Collocations Dictionary (2009), (2) the online British National Corpus (3) consultations with two native speakers[1], and (4) the acceptability-of-collocations survey, which was used to triangulate the above three methods. Overall, the results from the academic writing data revealed that (1) verb-noun collocations were more difficult for the participants than adjective-noun collocations; and (2) the participants’ use of the twelve adjectives in adjective-noun collocations showed significantly more accuracy ratings compared to their use of the twelve verbs in verb-noun collocations. [1] According to Crystal (1997), the term native-speaker is used in the linguistic field to refer to “someone for whom a particular LANGUAGE is a ‘native language’ (also called ‘first language’, ‘mother-tongue’)”. The implication is the acquisition of this language has taken place since childhood. Therefore, it can be safely asserted that a native speaker possesses the most reliable intuition and for that reason has the best judgement of how the language is used, making him/her the most trusted kind of informant.

Volatile Memory Message Carving: A per process basis Approach

The pace at which data and information transfer and storage has shifted from PCs to mobile devices is of great concern to the digital forensics community. Android is fast becoming the operating system of choice for these hand-held devices, hence the need to develop better forensic techniques for data recovery cannot be over-emphasized. This thesis analyzes the volatile memory for Motorola Android devices with a shift from traditional physical memory extraction to carving residues of data on a “per process basis”. Each Android application runs in a separate process within its own Dalvik Virtual Machine (JVM) instance, thus, the proposed “per process basis” approach. To extract messages, we first extract the runtime memory of the MotoBlur application, then carve and reconstruct both deleted and undeleted messages (emails and chat messages). An experimental study covering two Android phones is also presented

Negotiating Sexual Harassment: Experiences of Women Academic Leaders in Pakistan

This paper endeavors to explore sexual harassment encountered by women leaders in Pakistani academia. An in-depth interview method was used to gain insight from women academic administrators working in coeducational universities in two cities of Pakistan. The interviews were analyzed using Foucauldian discourse analysis. The findings highlight that women leaders were sexually harassed by men at positions of power as well as co-workers and subordinates. The acts of harassment were expressed mostly through the use of inappropriate language such as jokes, demeaning comments and sexual remarks, undue offers of promotion for exchange of favors, and use of traditional words instead of their official titles as in the case of men. The subordinates often took advantage of their old age to defy women’s positions of power. Young and single women were more likely to experience sexual harassment and were considered ‘available.’ The participants perceived such acts as a means of control through which men strengthen the gender-based power relations in the academia. The fact that women are discouraged to report acts of harassment shows that the dominant masculine discourses legitimize and defend the acts of male harassment at the workplace. Since women are aware of this normalization of harassment, they engaged in culturally appropriate strategies to cope with the violence such as keeping their distance, and through loud and harsh tones in response. The paper recommends the need for non-hierarchical, consultative, and gender-sensitive approaches in universities to combat sexual harassment and increase the representation of women at top leadership positions

Malware Analysis and Privacy Policy Enforcement Techniques for Android Applications

The rapid increase in mobile malware and deployment of over-privileged applications over the years has been of great concern to the security community. Encroaching on user’s privacy, mobile applications (apps) increasingly exploit various sensitive data on mobile devices. The information gathered by these applications is sufficient to uniquely and accurately profile users and can cause tremendous personal and financial damage. On Android specifically, the security and privacy holes in the operating system and framework code has created a whole new dynamic for malware and privacy exploitation. This research work seeks to develop novel analysis techniques that monitor Android applications for possible unwanted behaviors and then suggest various ways to deal with the privacy leaks associated with them. Current state-of-the-art static malware analysis techniques on Android-focused mainly on detecting known variants without factoring any kind of software obfuscation. The dynamic analysis systems, on the other hand, are heavily dependent on extending the Android OS and/or runtime virtual machine. These methodologies often tied the system to a single Android version and/or kernel making it very difficult to port to a new device. In privacy, accesses to the database system’s objects are not controlled by any security check beyond overly-broad read/write permissions. This flawed model exposes the database contents to abuse by privacy-agnostic apps and malware. This research addresses the problems above in three ways. First, we developed a novel static analysis technique that fingerprints known malware based on three-level similarity matching. It scores similarity as a function of normalized opcode sequences found in sensitive functional modules and application permission requests. Our system has an improved detection ratio over current research tools and top COTS anti-virus products while maintaining a high level of resiliency to both simple and complex obfuscation. Next, we augment the signature-related weaknesses of our static classifier with a hybrid analysis system which incorporates bytecode instrumentation and dynamic runtime monitoring to examine unknown malware samples. Using the concept of Aspect-oriented programming, this technique involves recompiling security checking code into an unknown binary for data flow analysis, resource abuse tracing, and analytics of other suspicious behaviors. Our system logs all the intercepted activities dynamically at runtime without the need for building custom kernels. Finally, we designed a user-level privacy policy enforcement system that gives users more control over their personal data saved in the SQLite database. Using bytecode weaving for query re-writing and enforcing access control, our system forces new policies at the schema, column, and entity levels of databases without rooting or voiding device warranty

Ab INITIO CALCULATION OF ELECTRONIC AND OPTICAL PROPERTIES OF BERYLLIUM CHALCOGENIDES (BeS, BeSe, AND BeTe) UNDER THE EFFECT OF PRESSURE

There are several methods for materials simulation. Ab initio or first principles methods are used to solve the quantum mechanical equation which govern the behavior of a system. Ab initio calculation of the optical and electronic properties of solids is fundamental in solid state physics. APW+lo is used to examine different properties of BeS, BeSe and BeTe. Beryllium compounds show different features in structure under different pressures, and they also show a phase transition from Zinc blende to Hexagonal transitions in II-VI semiconductors. Little is known about the ground state properties of Beryllium Chalcogenides. The aim of this work is to examine the electronical and optical properties of these materials, with the emphasis on their dependence on hydrostatic pressure. First, we calculated the electronic properties such as band structure, charge density, density of state, and the contours of these materials, second we examined their optical properties such as refractive index, the dielectric function (both real and imaginary), and the coefficient of absorption under normal and transient pressure. Two packages: the Wien97 and the Wien2k, are used in our simulation

Diagnostic Accuracy of Magnetic Resonance Imaging (MRI) in Detecting Parametrial Invasion in Carcinoma of Cervix

Objective: To evaluate the diagnostic accuracy of MRI in the evaluation of parametrical invasion in carcinoma of the cervix using histopathological findings as gold standard.Methodology: This Cross-sectional study was conducted at diagnostic radiology department of KIRAN hospital Karachi; study duration was 12 months from December 2012 to November 2013. All the patients having carcinoma of cervix proven by the biopsy were included in the study. MRI scan was performed using MRI system (Toshiba aport, 0.35 Tesla) with the pelvic array coil for the scan of the pelvis. After MRI the patients are referred to a gynecologist for hysterectomy and then surgical specimen was reviewed by two experienced histopathologists and reported the positive/negative parametrium invasion on surgical specimen.Results: The average age of the patients was 49.42 ± 8.92 years.  Sensitivity and specificity was 81.7% and 82.2% respectively. Positive and negative predictive values were 86% and 77.1%, while the accuracy of MRI in detecting parametrial invasion was 81.9%.Conclusion: It is concluded that MRI is a best diagnostic tool with high sensitivity, specificity, and accuracy in detecting parametrial invasion of cervix carcinoma and its exact staging, size and location