Wireless network security status in Oulu:war-driving

Abstract. Wireless networks have improvement not only in the timeliness, frequency, convenience and flexibility of connecting to the Internet, but also in economic cost and expansion of the number and location of access points that a user can connect to the internet. They have gained popularity especially after Wireless Local Area Network second evolvement about changing initial secure algorithm Wired Equivalent Privacy (WEP) to Wi-Fi Protected Access (WPA) and WPA2. WEP has been found to have vulnerabilities in cryptographic techniques and can’t defend against brute force attacks for more than a few minutes and is considered broken nowadays. WPA, a stronger encryption algorithm than WEP, made Wi-Fi a reliable network connection method. Wi-Fi security issues have been found probably since the first wireless network was deployed, but it is widely known by people because of Peter Shipley’s wardriving experimentation and the statistic report which has been published in hacker conference in 2001. Several experiments have been carried out to reveal Wi-Fi security issues and to improve users’ awareness of Wi-Fi security. Wardriving is not a new concept, but only lately wardriving was becoming easier for wardrivers because of continued evolution of technology. The updated software and hardware that are utilized in wardriving have given this activity more economic value and attracted interest from other researchers too. But this method has not yet been used in Oulu, at least in academic research. No studies have reported about wireless network security status with wardriving method by flying a drone to discover wireless APs and most of wardriving has been done by car, walking, or biking. Furthermore, Oulu, as a technology hub with many ICT companies and citywide panOULU public Wi-Fi infrastructure, makes it an ideal location for this experiment. What is Wi-Fi performance and security status in Oulu? Author will scan wireless networks in Oulu center area with a tool kit setting up with Raspberry Pi, Wi-Fi adaptor, GPS receiver and drone using a method called wardriving. Wardriving is the act of discovering and mapping wireless networks in a certain area and restoring access points’ data, such as an encryption standard, network name and location. The fundamental purpose is to find general information about Wi-Fi networks performance and security in Oulu center area and report the issues to raise the awareness of Wi-Fi security. Mobile devices do not need to be connected to wireless networks to be tracked. The Wi-Fi signal is transmitted continuously while a phone device tries to search for available networks. Whether discovered wireless devices quantification is indicative of local personnel density is another research question to be answered. About 65.22% wireless APs have WPA-CCMP encryption standard and 4.2% Wi-Fi have unknown authentication in Oulu. The data showed that the majority of wireless networks in Oulu are secure. Less than 1% networks deployed WEP which has been found severe flaws in authentication method and 10% wireless access points had WPA-TKIP deployed which employed the same underlying mechanism as WEP, therefore it is vulnerable to similar attacks. The amount of insecure networks brings some concerns to the wireless network security state in Oulu. Wardriving by drone turned out to be a more efficient method to discover wireless networks compared to wardriving on ground by walking or biking. The result also found that wireless device quantification is indicative of local personnel density, as almost everyone nowadays has a smartphone. This finding makes the Pi setup more practically usage, such as searching for lost people in forest. Thus, it becomes one future research direction, to build a real time indicator to show the direction and distance between the Pi setup and a specific wireless network device, based on the detected strength of signal

Primary Lung Intravascular Large B-Cell Lymphoma Clinically Mimicking Sarcoidosis: A Rare Case Report and Review of Literature

We present a case of a 73-year-old male who initially presented with night sweats, intermittent fever, worsening dry cough and shortness of breath. CT scans revealed atelectasis and calcified mediastinal lymphadenopathy, raising a suspicion for sarcoidosis. Multiple lung biopsies were performed. Microscopically, atypical lymphocytes were identified within capillaries, small arteries and veins. These lymphocytes were large with prominent nucleoli. Immunohistochemical staining demonstrated tumor cells positive for CD20, CD79a, Pax-5, CD10 and Mum-1, while negative for CD3, cytokeratin, S100, and CD34. LDH serum level was increased (480 IU/L). Extra pulmonary lymphoma was not detected elsewhere in the patient. These findings support the diagnosis of primary lung intravascular large B cell lymphoma (IVLBCL). Literature review of 52 cases demonstrated occurrence of primary lung IVBCL in patients between the ages (35–85) with a slight male predominance (1.167:1). The most common clinical presentation was fever associated with dyspnea

A new framework for consensus for discrete-time directed networks of multi-agents with distributed delays

Copyright @ 2012 Taylor & FrancisIn this article, the distributed consensus problem is considered for discrete-time delayed networks of dynamic agents with fixed topologies, where the networks under investigation are directed and the time-delays involved are distributed time delays including a single or multiple time delay(s) as special cases. By using the invariance principle of delay difference systems, a new unified framework is established to deal with the consensus for the discrete-time delayed multi-agent system. It is shown that the addressed discrete-time network with arbitrary distributed time delays reaches consensus provided that it is strongly connected. A numerical example is presented to illustrate the proposed methods.This work was supported in part by City University of Hong Kong under Grant 7008114, the Royal Society of the UK, the National Natural Science Foundation of China under Grants 60774073 and 61074129, and the Natural Science Foundation of Jiangsu Province of China under Grant BK2010313

State estimation for discrete-time neural networks with Markov-mode-dependent lower and upper bounds on the distributed delays

Copyright @ 2012 Springer VerlagThis paper is concerned with the state estimation problem for a new class of discrete-time neural networks with Markovian jumping parameters and mixed time-delays. The parameters of the neural networks under consideration switch over time subject to a Markov chain. The networks involve both the discrete-time-varying delay and the mode-dependent distributed time-delay characterized by the upper and lower boundaries dependent on the Markov chain. By constructing novel Lyapunov-Krasovskii functionals, sufficient conditions are firstly established to guarantee the exponential stability in mean square for the addressed discrete-time neural networks with Markovian jumping parameters and mixed time-delays. Then, the state estimation problem is coped with for the same neural network where the goal is to design a desired state estimator such that the estimation error approaches zero exponentially in mean square. The derived conditions for both the stability and the existence of desired estimators are expressed in the form of matrix inequalities that can be solved by the semi-definite programme method. A numerical simulation example is exploited to demonstrate the usefulness of the main results obtained.This work was supported in part by the Royal Society of the U.K., the National Natural Science Foundation of China under Grants 60774073 and 61074129, and the Natural Science Foundation of Jiangsu Province of China under Grant BK2010313

Transferability of N-terminal mutations of pyrrolysyl-tRNA synthetase in one species to that in another species on unnatural amino acid incorporation efficiency

Genetic code expansion is a powerful technique for site-specific incorporation of an unnatural amino acid into a protein of interest. This technique relies on an orthogonal aminoacyl-tRNA synthetase/tRNA pair and has enabled incorporation of over 100 different unnatural amino acids into ribosomally synthesized proteins in cells. Pyrrolysyl-tRNA synthetase (PylRS) and its cognate tRNA from Methanosarcina species are arguably the most widely used orthogonal pair. Here, we investigated whether beneficial effect in unnatural amino acid incorporation caused by N-terminal mutations in PylRS of one species is transferable to PylRS of another species. It was shown that conserved mutations on the N-terminal domain of MmPylRS improved the unnatural amino acid incorporation efficiency up to five folds. As MbPylRS shares high sequence identity to MmPylRS, and the two homologs are often used interchangeably, we examined incorporation of five unnatural amino acids by four MbPylRS variants at two temperatures. Our results indicate that the beneficial N-terminal mutations in MmPylRS did not improve unnatural amino acid incorporation efficiency by MbPylRS. Knowledge from this work contributes to our understanding of PylRS homologs which are needed to improve the technique of genetic code expansion in the future

Lattice Boltzmann simulation of alumina-water nanofluid in a square cavity

A lattice Boltzmann model is developed by coupling the density (D2Q9) and the temperature distribution functions with 9-speed to simulate the convection heat transfer utilizing Al2O3-water nanofluids in a square cavity. This model is validated by comparing numerical simulation and experimental results over a wide range of Rayleigh numbers. Numerical results show a satisfactory agreement between them. The effects of Rayleigh number and nanoparticle volume fraction on natural convection heat transfer of nanofluid are investigated in this study. Numerical results indicate that the flow and heat transfer characteristics of Al2O3-water nanofluid in the square cavity are more sensitive to viscosity than to thermal conductivity

Genome-Wide Divergence of DNA Methylation Marks in Cerebral and Cerebellar Cortices

Emerging evidence suggests that DNA methylation plays an expansive role in the central nervous system (CNS). Large-scale whole genome DNA methylation profiling of the normal human brain offers tremendous potential in understanding the role of DNA methylation in brain development and function.Using methylation-sensitive SNP chip analysis (MSNP), we performed whole genome DNA methylation profiling of the prefrontal, occipital, and temporal regions of cerebral cortex, as well as cerebellum. These data provide an unbiased representation of CpG sites comprising 377,509 CpG dinucleotides within both the genic and intergenic euchromatic region of the genome. Our large-scale genome DNA methylation profiling reveals that the prefrontal, occipital, and temporal regions of the cerebral cortex compared to cerebellum have markedly different DNA methylation signatures, with the cerebral cortex being hypermethylated and cerebellum being hypomethylated. Such differences were observed in distinct genomic regions, including genes involved in CNS function. The MSNP data were validated for a subset of these genes, by performing bisulfite cloning and sequencing and confirming that prefrontal, occipital, and temporal cortices are significantly more methylated as compared to the cerebellum.These findings are consistent with known developmental differences in nucleosome repeat lengths in cerebral and cerebellar cortices, with cerebrum exhibiting shorter repeat lengths than cerebellum. Our observed differences in DNA methylation profiles in these regions underscores the potential role of DNA methylation in chromatin structure and organization in CNS, reflecting functional specialization within cortical regions