A new approach to malware detection

Malware is a type of malicious programs, and is one of the most common and serious types of attacks on the Internet. Obfuscating transformations have been widely applied by attackers to malware, which makes malware detection become a more challenging issue. There has been extensive research to detect obfuscated malware. A promising research direction uses both control-flow graph and instruction classes of basic blocks as the signature of malware. This research direction is robust against certain obfuscation, such as variable substitution, instruction reordering. But only using instruction classes to detect obfuscated basic blocks will cause high false positives and false negatives. In this thesis, based on the same research direction, we proposed an improved approach to detect obfuscated malware. In addition to using CFG, our approach also uses functionalities of basic block as the signature of malware. Specifically, our contributions are presented as follows: 1) we design "signature calculation algorithm" to extract the signature of a malicious code fragment. "Signature calculation algorithm" is based on compiler optimization algorithm, but add and integrate memory sub-variable optimization, expression formalization and cross basic block propagation into it. 2) we formalize the expressions of assignment statements to facilitate comparing the functionalities of two expressions. 3) we design a detection algorithm to detect whether a program is an obfuscated malware instance. Our detection algorithm compares two aspects: CFG and the functionalities of basic blocks. 4) we implement the proposed approach, and perform experiments to compare our approach and the previous approach

Eigenvalue problem for p-Laplacian three-point boundary value problems on time scales

AbstractLet T be a time scale such that 0,T∈T, β,γ⩾0 and 0<η<ρ(T). We consider the following p-Laplacian three-point boundary problem on time scales(φp(uΔ(t)))∇+λh(t)f(u(t))=0,t∈(0,T),u(0)−βuΔ(0)=γuΔ(η),uΔ(T)=0, where p>1, λ>0, h∈Cld((0,T),[0,∞)) and f∈C([0,∞),(0,∞)). Some sufficient conditions for the nonexistence and existence of at least one or two positive solutions for the boundary value problem are established. In doing so the usual restriction that f0=limu→0+f(u)φp(u) and f∞=limu→∞f(u)φp(u) exist is removed. An example is also given to illustrate the main results

PREPARATION OF MACROPOROUS TIO2 BY STARCH MICROSPHERES TEMPLATE WITH ASSISTANCE OF SUPERCRITICAL CO2

In this work a green route is reported to prepare a TiO2 macroporous network using corn starch microspheres flake as a bio-template. The starch microspheres prepared by emulsion technology were used as a template into which precursor tetrabutyl titanate (TBOT) was permeated using supercritical carbon dioxide (scCO2) as a forceful carrier or infiltration media, resulting in the formation of an organic/inorganic hybrid material; then the coated template was gelled and dried during the scCO2-coating and the depressurization processes, followed by removal of the template by calcination at 700°C; finally, TiO2 inverse-opals-like material reversely replicating the starch microspheres template was obtained. Scanning electron microscopy (SEM), nitrogen sorption measurements, and X-ray diffraction (XRD) indicated that the products were the inverse replicas from their templates. The obtained TiO2 inverse opals-like material showed a wide dispersion of pore sizes from mesopores to macropores – a few nanometers to several micrometers –with the BET surface area up to 103 m2/g, and a predominantly anatase crystalline phase. In addition, the wall thickness of the macropores varied with tunable pressure for closed cells or open-cell foams. So this facile and environmentally friendly process for the preparation of high-surface area, thermally-stable, metal-oxide catalysts and supports by a starch microsphere templating approach may have widespread potential applications in catalysis, absorbents, photoelectric materials, and so on

Eucommia ulmoides

Cortex Eucommiae (Du-zhong) is the dried bark of the Eucommia ulmoides Oliv. The natural products identified from Du-zhong include lignans, iridoids, flavonoids, polysaccharides, terpenes, and proteins, Liu et al. (2012). Lignans, the main bioactive components, were protective against hypertensive renal injury in spontaneous hypertensive rats in our previous study, Li et al. (2012). Moreover, Eucommia lignans also diminished aldose reductase (AR) overexpression in the kidney, Li et al. (2012). However, the pathological mechanism underlying the protective effects of Eucommia lignans remains unknown. Cellular proliferation was reported to contribute to important pathological changes in hypertensive renal injuries, and increased angiotensin II (Ang II) expression was reported to be essential for target-organ damage during hypertension. Ang II is the main effective peptide in the renin-angiotensin system and is considered to be a key mediator in the development of hypertensive nephropathy, Rüster and Wolf (2011). Our preliminary results showed that Eucommia lignans had inhibitory effects on Ang II-induced proliferation of rat mesangial cells. In the present study, we investigated the effects of Eucommia ulmoides on Ang II-induced proliferation and apoptosis of rat mesangial cells. Cell cycle-related genes P21 and P27, and cell apoptosis-related genes Bax and Bcl-2, were determined

Design and Performance Evaluation of a Biometric Iris Verification System

This paper describes an iris verification project focused on design and performance evaluation under both matched and mismatched training and testing conditions. Training is always performed on clean iris images. Testing is performed on both clean and noisy iris images. This project is part of a senior undergraduate course on biometric systems. In implementing an iris recognition system, students go through each step, namely, preprocessing, feature extraction, classification (training and use in rendering a decision) and performance evaluation. The Chinese Academy of Sciences - Institute of Automation(CASIA) eye image database known as the CASIA-Iris-Interval-v3 database is used to show students that robustness to mismatched training and testing conditions is a significant practical issue

Planning and Assessment of a Workshop on Undergraduate Education in Biometric Systems

Biometrics is the science of recognizing and authenticating people using their physiological features. Border and immigration control, restricted access to facilities and information systems, cybersecurity, crime investigations and forensic analysis are just a few of the primary application areas of biometrics used by commercial, government and law enforcement agencies. The global biometrics market has a compound annual growth rate of 21.3 percent. There is much research interest in different biometric systems and this has led to increasing efforts in ensuring that biometrics is taught at the undergraduate level. The authors are in the final year of an NSF TUES Type 2 grant that is based on the theme of vertically integrating biometrics experiments throughout the undergraduate curriculum. Three universities have joined together in this effort. This paper is about the planning and assessment of a 3 day workshop that is based on the NSF funded effort. Fifteen faculty from across the country participated in this workshop. Undergraduate and graduate students also attended. The key points of the workshop included invited lectures and hands-on laboratory activities. The invited lectures included a tutorial on biometrics, detailed lectures on speaker recognition and a lecture on how to assess an educational intervention. The hands-on activities were presented such that the attending faculty could take them back to their respective universities. They were based on the following learning outcomes: • Enhanced application of math skills • Enhanced software implementation skills • Enhanced interest in biometrics • Enhanced ability to analyze experimental results • Enhanced communication skills • Comprehension of the importance of vertical integration, in that students realize that their experiences are part of a flow that contributes to a unified knowledge base. The workshop assessment results are very positive with respect to organization, quality of the invited lectures, quality of the hands-on activities and the social program