Using Insider Swapping of Time Intervals to Perform Highly Invisible Network Flow Watermarking

Network flow watermarking (NFW) is an emerging flow correlation technique to deanonymize an anonymous communication system or detect stepping stones, in which a watermark is encoded into a network flow by manipulating some flow characteristics, predominantly by altering timing information. Although interval-based NFWs that employ time intervals as carrier have proven to be capable of resisting moderate network interference, they are vulnerable to some statistic-based attacks, which may expose the very existence of watermark and enable attackers to damage or remove watermark from the observed flow. In this study, using insider swapping of time intervals and an adaptive centroid quantization framework, we design a highly invisible NFW scheme, which is undetectable by multi-flow attacks (MFA), Kullback-Leibler divergence (KLD) test, Kolmogorov-Smirnov (K-S) test, and spread spectrum flow watermark (SSFW) detection. Experimental results using real traffic and public dataset show that the proposed NFW scheme can outperform three typical NFW schemes on invisibility while maintaining a strong interference-resistance capability of network jitter, packet loss, and dummy packet insertion.

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Experimental Investigation of Water-Sand Mixed Fluid Initiation and Migration in Filling Fracture Network during Water Inrush

Advances in Civil Engineering ◽

10.1155/2021/6618504 ◽

2021 ◽

Vol 2021 ◽

pp. 1-20

Author(s):

Bin Yang ◽

Tianhong Yang

Keyword(s):

Particle Size ◽

Critical Velocity ◽

Network Flow ◽

Water Inrush ◽

Functional Relation ◽

Flow Characteristics ◽

Fracture Network ◽

Nonlinear Flow ◽

Two Phase ◽

And Migration

For water inrush induced by fracture network flow, the critical velocity of the incipient motion of sand particles was obtained, and the functional relation between critical velocity and particle size was established through a series of tests on the nonlinear flow characteristics of a filling fracture network. The influence of the particle size distribution, hydrodynamic force, and geometric features of the fracture network on the characteristics of particle loss; distribution laws; and water-sand, two-phase migration was also explored. Moreover, the interactions amongst water, movable particles, the surface of the skeleton, and fracture walls, and the formation mechanism of the flow channel were qualitatively analyzed. In addition, the change rules of the mass loss characteristics and porosity of the samples with time were tested successfully. The calculation methods of the permeability and non-Darcy factor of the filling fracture network were also determined.

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PENGARUH KOMBINASI EKSTRAK JERUK BRASTAGI DAN WORTEL PER ORAL SEBELUM AKTIVITAS FISIK TERHADAP PENURUNAN KADAR MDA PLASMA MENCIT SETELAH AKTIVITAS FISIK

JURNAL ILMU FAAL OLAHRAGA INDONESIA ◽

10.51671/jifo.v1i1.23 ◽

2017 ◽

Vol 1 (1) ◽

pp. 41

Author(s):

Nurvidya Rachma Dewi ◽

Ambrosius Purba ◽

Beltasar Tarigan

Keyword(s):

Physical Activity ◽

Free Radicals ◽

Cellular Level ◽

Not Given ◽

Time Intervals ◽

Kolmogorov Smirnov ◽

Group A ◽

The Difference ◽

Group B ◽

Per Oral

Aerobic metabolism in the cellular level generates free radicals. Under normal condition,theres balance between free radicals and endogenous antioxidants. Excessive amount of freeradicals impair DNA, protein, fat, etc. The level of free radicals can be known by measuringplasma malondialdehyde level. Combination of Brastagis oranges and carrots juice asexogenous antioxidants supplementation expected to decrease free radicals level . The aim of thisstudy is to investigate the difference of plasma MDA level during several time intervals on micewhich is given and not given combination of Brastagis oranges and carrots juice before physicalactivity using mices treadmill for 20 minutes. The research method used in this study is anexperimental laboratory study. The objects of this study are 40 mice (mus musculus), whitecolored, male, weighting 25-30 grams, which is randomly chosen. The objects are divided into 2groups, Group A : 20 mice (given combination of Brastagis oranges and carrots juice beforephysical activity using mices treadmill) and group B : 20 mice (not given combination ofBrastagis oranges and carrots juice before physical activity using mices treadmill). Group Aare divided into 5 subgroups: A1 (measurement of plasma MDA level at 0 minute after treadmill),A2 (measurement of plasma MDA level at 15 minutes after treadmill), and A3 (measurement ofplasma MDA level at 30 minutes after treadmill), A4 (measurement of plasma MDA level at 60minutes after treadmill), and A5 (measurement of plasma MDA level at 240 minutes aftertreadmill). The same procedures are employed for the group B. Plasma MDA level measuredafter doing physical activity using mice treadmill. The homogenity of the result then was testedusing Levenes test and the normality of the result was tested using Kolmogorov-smirnov test (p>0.05). Further, the data was analyzed using independent t-test (p?0.05), one-way ANOVA(p?0.05) then Duncans test were used. The results reveal significant lowering plasma MDAconcentration in mice receiving combination of Brastagis oranges and carrots juice beforephysical activity, which is measured during several time intervals : 0,15,30,60, and 240 minutesafter physical activity than in mice not receiving combination of Brastagis oranges and carrotsjuice before physical activity. The MDA level differences between groups which is given and notgiven combination of Brastagis orange and carrots juice before physical activity measuredduring several intervals are 11,44% (0,8920 vs 1,0071) measured 0 minute after physical activity,15,47% (0,7902 vs 0,9348) measured 15 minutes after physical activity, 14,42% (0,7473 vs0,8732) measured 30 minutes after physical activity, 11,35% (0,6696 vs 0,7554) measured 60minutes after physical activity, and 13,60% (0,5786 vs 0,6696) measured 240 minutes afterphysical activity.The conclusion of the study suggested that combination of Brastagis orange andcarrots juice supplementation has lowering effect toward plasma MDA level measured duringseveral time intervals.

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Using the Kullback-Leibler Divergence and Kolmogorov-Smirnov Test to Select Input Sizes to the Fault Diagnosis Problem Based on a CNN Model

Learning and Nonlinear Models ◽

10.21528/lnlm-vol18-no2-art2 ◽

2021 ◽

Vol 18 (2) ◽

pp. 16-26

Author(s):

Rodrigo Paula Monteiro ◽

◽

Carmelo Jose Albanez Bastos-Filho ◽

Mariela Cerrada ◽

Diego Cabrera ◽

...

Keyword(s):

Fault Diagnosis ◽

Classification Model ◽

Data Sets ◽

Frequency Spectra ◽

Signal Representations ◽

Input Size ◽

Leibler Divergence ◽

Classifier Performance ◽

Kolmogorov Smirnov ◽

Smirnov Test

Choosing a suitable size for signal representations, e.g., frequency spectra, in a given machine learning problem is not a trivial task. It may strongly affect the performance of the trained models. Many solutions have been proposed to solve this problem. Most of them rely on designing an optimized input or selecting the most suitable input according to an exhaustive search. In this work, we used the Kullback-Leibler Divergence and the Kolmogorov-Smirnov Test to measure the dissimilarity among signal representations belonging to equal and different classes, i.e., we measured the intraclass and interclass dissimilarities. Moreover, we analyzed how this information relates to the classifier performance. The results suggested that both the interclass and intraclass dissimilarities were related to the model accuracy since they indicate how easy a model can learn discriminative information from the input data. The highest ratios between the average interclass and intraclass dissimilarities were related to the most accurate classifiers. We can use this information to select a suitable input size to train the classification model. The approach was tested on two data sets related to the fault diagnosis of reciprocating compressors.

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A Sequence-Based Damage Identification Method for Composite Rotors by Applying the Kullback–Leibler Divergence, a Two-Sample Kolmogorov–Smirnov Test and a Statistical Hidden Markov Model

Entropy ◽

10.3390/e21070690 ◽

2019 ◽

Vol 21 (7) ◽

pp. 690 ◽

Cited By ~ 1

Author(s):

Angelos Filippatos ◽

Albert Langkamp ◽

Pawel Kostka ◽

Maik Gude

Keyword(s):

Markov Model ◽

Hidden Markov Model ◽

Composite Structures ◽

Damage Identification ◽

Hidden Markov ◽

Structural Dynamic ◽

Identification Method ◽

Leibler Divergence ◽

Kolmogorov Smirnov ◽

Smirnov Test

Composite structures undergo a gradual damage evolution from initial inter-fibre cracks to extended damage up to failure. However, most composites could remain in service despite the existence of damage. Prerequisite for a service extension is a reliable and component-specific damage identification. Therefore, a vibration-based damage identification method is presented that takes into consideration the gradual damage behaviour and the resulting changes of the structural dynamic behaviour of composite rotors. These changes are transformed into a sequence of distinct states and used as an input database for three diagnostic models, based on the Kullback–Leibler divergence, the two-sample Kolmogorov–Smirnov test and a statistical hidden Markov model. To identify the present damage state based on the damage-dependent modal properties, a sequence-based diagnostic system has been developed, which estimates the similarity between the present unclassified sequence and obtained sequences of damage-dependent vibration responses. The diagnostic performance evaluation delivers promising results for the further development of the proposed diagnostic method.

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PaleoJump database for research on rapid climate transitions

10.5194/egusphere-egu21-9968 ◽

2021 ◽

Author(s):

Witold Bagniewski ◽

Denis-Didier Rousseau ◽

Michael Ghil

Keyword(s):

Time Intervals ◽

Origin Time ◽

Essential Information ◽

The Earth ◽

Dating Methods ◽

Long Time ◽

Kolmogorov Smirnov ◽

Paleoclimate Records ◽

Smirnov Test ◽

Climate Transitions

Tipping points (TPs) in the Earth system have been studied with growing interest and concern in recent years due to the potential risk of anthropogenic forcing causing abrupt, and possibly irreversible, climate transitions. Paleoclimate records are essential for identifying TPs in the Earth&#8217;s past and to properly understand the climate system&#8217;s underlying bifurcation mechanisms. Due to their varying quality, resolution, and dating methods, it is often necessary to select the records that give the best representation of past climate. Furthermore, as paleoclimate records vary in their origin, time spans, and periodicities, an objective, automated methodology is crucial for identifying and comparing TPs. To reach this goal, here we present the PaleoJump database of carefully selected, high-resolution records originating in ice, marine sediments, speleothems, loess, and lake sediments. These records, which include tipping elements, cover long time intervals and represent a global distribution from all continents and ocean basins. For every record, a transition detection methodology based on an augmented Kolmogorov-Smirnov test is applied to identify abrupt transitions. The PaleoJump database highlights these automatically detected transitions for every record together with other essential information, including location, temporal scale and resolution, as well as temporal plots; it therefore represents a valuable resource for researchers investigating TPs in past climates. This study is supported by the H2020-funded TiPES project.

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An Assessment of Six Dissimilarity Metrics for Climate Analogs

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-12-0170.1 ◽

2013 ◽

Vol 52 (4) ◽

pp. 733-752 ◽

Cited By ~ 20

Author(s):

Patrick Grenier ◽

Annie-Claude Parent ◽

David Huard ◽

François Anctil ◽

Diane Chaumont

Keyword(s):

Large Scale ◽

Nearest Neighbor ◽

Climate Model ◽

Regional Climate ◽

A Priori ◽

Degree Days ◽

Leibler Divergence ◽

Cooling Degree Days ◽

Kolmogorov Smirnov ◽

Heating Degree Days

AbstractSpatial analog techniques consist in identifying locations whose historical climate is similar to the anticipated future climate at a reference location. In the process of identifying analogs, one key step is the quantification of the dissimilarity between two climates separated in time and space, which involves the choice of a metric. In this study, six a priori suitable metrics are described (the standardized Euclidean distance, the Kolmogorov–Smirnov statistic, the nearest-neighbor distance, the Zech–Aslan energy statistic, the Friedman–Rafsky runs statistic, and the Kullback–Leibler divergence) and criteria are proposed and investigated in an attempt to identify the best metric for selecting spatial analogs. The case study involves the use of numerical simulations performed with the Canadian Regional Climate Model (CRCM, version 4.2.3), from which three annual indicators (total precipitation, heating degree-days, and cooling degree-days) are calculated over 30-yr periods (1971–2000 and 2041–70). It is found that the six metrics identify comparable analog regions at a relatively large scale but that best analogs may differ substantially. For best analogs, it is shown that the uncertainty stemming from the metric choice does not generally exceed that stemming from the simulation or model choice. On the basis of the set of criteria considered in this study, the Zech–Aslan energy statistic stands out as the most recommended metric for analog studies, whereas the Friedman–Rafsky runs statistic is the least recommended.

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Role Recognition Method Based on Network Flow Characteristics

DEStech Transactions on Computer Science and Engineering ◽

10.12783/dtcse/cscme2019/32547 ◽

2019 ◽

Author(s):

Tao YU ◽

Rui-qi YUE

Keyword(s):

Network Flow ◽

Flow Characteristics ◽

Recognition Method

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Minimizing the Embedding Impact Using Network Flow Algorithms

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.341-342.478 ◽

2011 ◽

Vol 341-342 ◽

pp. 478-483

Author(s):

Wan Qi Li ◽

Heng Wang ◽

Che Nian ◽

Huang Wei ◽

Hong Yao You

Keyword(s):

Network Flow ◽

Optimization Problems ◽

Computational Cost ◽

Distortion Function ◽

Cover Image ◽

Leibler Divergence ◽

Novel Method ◽

Low Computational Cost

A novel method of minimizing the embedding impact is proposed in this paper. Optimal embedding is achieved using network flow algorithms by considering the modifications on the cover image as flows of pixels among different states. This method is not an independent steganographic scheme, but rather it minimizes the embedding impact after the embedding process and it’s compatible with the majority of embedding techniques. Due to its dependence on the embedding process, many optimization problems, such as the minimization of a globally interactive distortion function, that are intractable during the embedding process can be solved with relatively low computational cost by rectifying the modifications on the cover image after the embedding process. A distortion function based on Kullback-Leibler divergence is provided as a concrete example to illustrate the basic idea of this method.

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PENGARUH KOMBINASI EKSTRAK JERUK BRASTAGI DAN WORTEL PER ORAL SEBELUM AKTIVITAS FISIK TERHADAP PENURUNAN KADAR MDA PLASMA MENCIT SETELAH AKTIVITAS FISIK

JURNAL ILMU FAAL OLAHRAGA INDONESIA ◽

10.51671/jifo.v1i2.87 ◽

2021 ◽

Vol 1 (2) ◽

pp. 64

Author(s):

Nurvidya Rachma Dewi ◽

Ambrosius Purba ◽

Beltasar Tarigan

Keyword(s):

Physical Activity ◽

Free Radicals ◽

Cellular Level ◽

Not Given ◽

Time Intervals ◽

Experimental Laboratory ◽

Kolmogorov Smirnov ◽

Group A ◽

The Difference ◽

Group B

Aerobic metabolism at the cellular level generates free radicals. Under normal conditions, there’s a balance between free radicals and endogenous antioxidants. An excessive amount of free radicals impair DNA, protein, fat, etc. The level of free radicals can be known by measuring plasma malondialdehyde level. Combination of Brastagi’s oranges and carrots juice as exogenous antioxidants supplementation expected to decrease free radicals level. The aim of this study is to investigate the difference of plasma MDA level during several time intervals on mice which are given and not given a combination of Brastagi’s oranges and carrots juice before physical activity using mice’s treadmill for 20 minutes. The research method used in this study is an experimental laboratory study. The objects of this study are 40 mice (mus musculus), white-colored, male, weighting 25-30 grams, which is randomly chosen. The objects are divided into 2 groups, Group A: 20 mice (given a combination of Brastagi’s oranges and carrots juice before physical activity using mice’s treadmill) and group B: 20 mice (not given a combination of Brastagi’s oranges and carrots juice before physical activity using mice’s treadmill). Group A is divided into 5 subgroups: A1 (measurement of plasma MDA level at 0 minutes after treadmill), A2 (measurement of plasma MDA level at 15 minutes after treadmill), and A3 (measurement of plasma MDA level at 30 minutes after treadmill), A4 (measurement of plasma MDA level at 60 minutes after treadmill), and A5 (measurement of plasma MDA level at 240 minutes after treadmill). The same procedures are employed for group B. Plasma MDA level measured after doing a physical activity using mice treadmill. The homogeneity of the result then was tested using Levene’s test and the normality of the result was tested using the Kolmogorov-Smirnov test (p>0.05). Further, the data were analyzed using an independent t-test (p≤0.05), one-way ANOVA (p≤0.05) then Duncan’s test were used. The results reveal significant lowering plasma MDA concentration in mice receiving a combination of Brastagi’s oranges and carrots juice before physical activity, which is measured during several time intervals: 0,15,30,60, and 240 minutes after physical activity than in mice not receiving a combination of Brastagi’s oranges and carrots juice before physical activity. The MDA level differences between groups that are given and not given combination of Brastagi’s orange and carrots juice before physical activity measured during several intervals are 11,44% (0,8920 vs 1,0071) measured 0 minutes after physical activity, 15,47% (0,7902 vs 0,9348) measured 15 minutes after physical activity, 14,42% (0,7473 vs 0,8732) measured 30 minutes after physical activity, 11,35% (0,6696 vs 0,7554) measured 60 minutes after physical activity, and 13,60% (0,5786 vs 0,6696) measured 240 minutes after physical activity.The conclusion of the study suggested that a combination of Brastagi’s orange and carrots juice supplementation has a lowering effect toward plasma MDA level measured during several time intervals.

Download Full-text