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A Dual-Chaining Watermark Scheme for Data Integrity Protection in Internet of Things
Get PDFChaining watermark is an effective way to verify the integrity of streaming data in wireless network environment, especially in resource-constrained sensor networks, such as the perception layer of Internet of Things applications. However, in all existing single chaining watermark schemes, how to ensure the synchronization between the data sender and the receiver is still an unsolved problem. Once the synchronization points are attacked by the adversary, existing data integrity authentication schemes are difficult to work properly, and the false negative rate might be up to 50 percent. And the additional fixed group delimiters not only increase the data size, but are also easily detected by adversaries. In this paper, we propose an effective dual-chaining watermark scheme, called DCW, for data integrity protection in smart campus IoT applications. The proposed DCW scheme has the following three characteristics: (1) In order to authenticate the integrity of the data, fragile watermarks are generated and embedded into the data in a chaining way using dynamic grouping; (2) Instead of additional fixed group delimiters, chained watermark delimiters are proposed to synchronize the both transmission sides in case of the synchronization points are tampered; (3) To achieve lossless integrity authentication, a reversible watermarking technique is applied. The experimental results and security analysis can prove that the proposed DCW scheme is able to effectively authenticate the integrity of the data with free distortion at low cost in our smart meteorological Internet of Things system
Few-Shot Learning with Generative Adversarial Networks Based on WOA13 Data
Get PDFIn recent years, extreme weather events accompanying the global warming have occurred frequently, which brought significant impact on national economic and social development. The ocean is an important member of the climate system and plays an important role in the occurrence of climate anomalies. With continuous improvement of sensor technology, we use sensors to acquire the ocean data for the study on resource detection and disaster prevention, etc. However, the data acquired by the sensor is not enough to be used directly by researchers, so we use the Generative Adversarial Network (GAN) to enhance the ocean data. We use GAN to process WOA13 dataset and use ResNet to determine if there is a thermocline layer in a sea area. We compare the classification results of the enhanced datasets of different orders of magnitude with the classification results of the original datasets. The experimental result shows that the dataset processed by GAN has a higher accuracy. GAN has a certain enhancement effect to marine data. Gan increased the accuracy of the WOA dataset from 0.91 to 0.93. At the same time, the experimental results also show that too much data cannot continue to enhance the accuracy of WOA in ResNet
Data Based Violated Behavior Analysis of Taxi Driver in Metropolis in China
Get PDFViolation probability of taxi drivers in metropolis is far more than that of normal drivers because they are labor-intensive, overconfident of self-driving skill, and always searching potential customers, sometimes even picking up or dropping off passengers randomly. In this paper, four types of violated behavior of taxi drivers in metropolis were first summarized, based on which corresponding scale table was initial designed with social statistical method. Furthermore, with certain samples, relative item analysis, exploratory factor analysis, validity analysis and reliability analysis were conducted to verify validity of the initial scale table, based on which some improvements were made, and we can see that the modified scale table in the paper has high fitness degree, good reliability and validity to detect violated behavior of taxi driver accurately. Finally, large area survey data of taxi driver questionnaire from Shanghai was collected with the modified scale table above, the analysis results showed that among four types of violated behavior of taxi drivers in metropolis, the probability over-speed is top to 89.57%, in which probabilities of behaviors of “driving over-speed at mid-night” and “accelerating to across the intersection during the yellow signal” are top to 64.2% and 58.2% respectively, which is meaningful for the improvement of taxi drivers’ behaviors specification and traffic safety regulation
Design and development of a dual-flow bioreactor mimicking intestinal peristalsis and permeability in epithelial tissue barriers for drug transport assessment
No full textWe present a bioreactor system which combines a semi permeable membrane that simulates the osmotic
nutrients interchange in the small intestine circulation and rhythmic peristaltic movement. This custom-designed
presents a semipermeable membrane bioreactor, with peristaltic flow and compression variation that allows adjustment
of luminal flow rate. In addition, this system is also capable of achieving the drug distribution in the small intestine
model from the apical compartment to the basal compartment by the semipermeable channel. This dynamic bioreactor
can mimic the human small intestine with increased accuracy to overcome many of the limitations and accuracy with
the previously described in vitro small intestinal models, providing a more representative model of the small intestine
Alteration of ADP-ribosylation in aging rat brain astrocytes
No full textDNA damage and the enzyme poly (ADP-ribose) polymerase (PARP) associated with the pathogenesis
of numerous age-related neurodegenerative disorders. Astrocytes play crucial roles in both support metabolic
functions and cell viability of the brain. PARP regulates DNA damage and repair in the brain cells. In this study PARP
activity and DNA strand break were investigated in the astrocytes isolated from young and aged rat brain. Three and
30-month-old rats were killed by decapitation and brains were removed onto an ice cooled glass plate. Astrocytes were
isolated by sucrose density gradient centrifugation and glutamine synthetase (GS) served as a marker of the astrocytes
lineage. The specific activity of PARP was assayed in permeabilized cells by measuring the incorporation of the ADPribose moiety of [3H]NAD into the nuclear acceptor proteins. The rate of DNA strand breaks was determined using
a fluorescent dye and monitored spectrofluorimetry. An increase (about 75%) in the PARP activity was observed in
the whole homogenates of aged rats, whereas this rise was more pronounced (about 360%) when the reaction was
measured in the purified astrocyte preparations. The amount of DNA strand breaks was also higher in the astrocytes
isolated from the aged brain as compared to that of young levels. The close relationship between the level of DNA
strand breaks and PARP activity in the astrocytes suggest that these cells are susceptible to the metabolic alterations in
aging. It is concluded that the astrocytes PARP might be considered as a therapeutic target for combating age related
neurodegenerative disorders
Heat Absorption and Joule Heating Effects on Transient Free Convective Reactive Micropolar Fluid Flow Past a Vertical Porous Plate
No full textMathematical model for an unsteady, incompressible, electrically conducting micropolar fluid past a vertical plate through porous medium with constant plate velocity has been investigated in the present study. Heat absorption, Joulian dissipation, and firstorder chemical reaction is also considered. Under the assumption of low Reynolds number, the governing transport equations are rendered into non-dimensional form and the transformed first order differential equations are solved by employing an efficient finite element method. Influence of various flow parameters on linear velocity, microrotation velocity, temperature, and concentration are presented graphically. The effects of heat absorption and chemical reaction rate decelerate the flow is particularly near the wall. Skin friction and wall couple stress increases as heat absorption increases but the reverse phenomenon is observed in the case of chemical reaction rate. Wall mass transfer rate increases for chemical reaction and Sherwood number increases for heat absorption. Finite element study is very versatile in simulating unsteady micropolar rheo-materials processing transport phenomena. However, a relatively simple reaction effects restricted to first order
The antitumor effects of Newcastle disease virus on glioma
No full textGlioma is the most common primary malignant brain tumor with a poor survival rate. In recent years, no
significant progress has been made in the treatment of gliomas in contrast to the development of improved diagnosis
via molecular typing. Newcastle disease virus (NDV), a negative-stranded RNA virus that exhibits oncolytic activity,
has been investigated for its capacity to elicit antitumor activity in many types of cancers, including glioma. Therefore,
application of oncolytic viruses, such as NDV, as a new treatment strategy to specifically target aberrant signaling in
glioblastomas has brought new hope. For many years, NDV has been investigated for its in vivo and in vitro efficacy in
the treatment of various tumor cells. Based on its safety in humans, specificity for tumor cells, and immunostimulatory
properties, NDV represents a promising antitumor agent. In this review, we summarize the background of NDV and
the antitumor mechanisms of NDV-mediated oncolysis, discuss the potential value and role of NDV in gliomas, and
describe new advances and perspectives for future research
Total Phenols, Flavonoids and Antioxidant Activity in <i>Annona muricata</i> and <i>Annona purpurea</i> Callus Culture
No full textCallus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog (MS) medium supplemented with different concentrations of 1-naphthylacetic acid (NAA), 6-benzyladenine (BA) and 2,4-dichlorophenoxyacetic acid (2,4-D) utilized hypocotyls with explant. The highest percentage of callus formation was the treatment supplemented with 3 mg L-1 NAA for A. muricata (100%) while for A. purpurea in lower percentage (75%). BA stimulated the formation of shoots in all the evaluated concentrations, being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for A. muricata (23 shoots/explant) and A. purpurea (28 shoots/explant). The content of total phenols, flavonoids and antioxidant activity was measured in the callus obtained from both species. The results showed that a higher content of total phenols was quantified in callus of A. purpurea (27.8 mg g-1 dw) compared to A. muricata (23.2 mg g-1 dw). The highest content of total flavonoids was observed in the callus of A. purpurea (8.0 μg g-1 dw). Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical assay. The concentration required for 50% inhibition (IC50) of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22 μg mL-1 in methanolic extracts of callus of A. muricata, while in extracts of callus of A. purpurea was 2.86 μg mL-1, in both cases was greater than that found for leaves. Callus culture of the species studied in this work represents an alternative for the production of natural antioxidants
Instant Edit Propagation on Images Based on Bilateral Grid
No full textThe ability to quickly and intuitively edit digital content has become increasingly important in our everyday life. However, existing edit propagation methods for editing digital images are typically based on optimization with high computational cost for large inputs. Moreover, existing edit propagation methods are generally inefficient and highly time-consuming. Accordingly, to improve edit efficiency, this paper proposes a novel edit propagation method using a bilateral grid, which can achieve instant propagation of sparse image edits. Firstly, given an input image with user interactions, we resample each of its pixels into a regularly sampled bilateral grid, which facilitates efficient mapping from an image to the bilateral space. As a result, all pixels with the same feature information (color, coordinates) are clustered to the same grid, which can achieve the goal of reducing both the amount of image data processing and the cost of calculation. We then reformulate the propagation as a function of the interpolation problem in bilateral space, which is solved very efficiently using radial basis functions. Experimental results show that our method improves the efficiency of color editing, making it faster than existing edit approaches, and results in excellent edited images with high quality
Iterative Solution of a System of Nonlinear Algebraic Equations F(x) = 0, Using x<sup style='margin-left:-6.5px'>·</sup> = λ[<i>α</i>R + <i>β</i>P] or x<sup style='margin-left:-6.5px'>·</sup> = λ[<i>α</i>F + <i>β</i>P<sup>∗</sup>] R is a Normal to a Hyper-Surface Function of F, P Normal to R, and P* Normal to F
No full textTo solve an ill- (or well-) conditioned system of Nonlinear Algebraic Equations (NAEs): F(x) = 0, we define a scalar hyper-surface h(x,t) = 0 in terms of x, and a monotonically increasing scalar function Q(t) where t is a time-like variable. We define a vector R which is related to ∂h / ∂x, and a vector P which is normal to R. We define an Optimal Descent Vector (ODV): u = αR + βP where α and β are optimized for fastest convergence. Using this ODV [x· = λu], we derive an Optimal Iterative Algorithm (OIA) to solve F(x) = 0. We also propose an alternative Optimal Descent Vector [u = αF + βP*] where P* is normal to F. We demonstrate the superior performance of these two alternative OIAs with ODVs to solve NAEs arising out of the weak-solutions for several ODEs and PDEs. More importantly, we demonstrate the applicability of solving simply, most efficiently, and highly accurately, the Duffing equation, using 8 harmonics in the Harmonic Balance Method to find a weak-solution in time