Enhanced dynamic source routing for verifying trust in mobile ad hoc network for secure routing

Secure data transfer in mobile ad hoc network (MANET) against malicious attacks is of immense importance. In this paper, we propose a new enhanced trust model for securing the MANET using trust-based scheme that uses both blind trust and referential trust. In order to do this, the trust relationship function has to be integrated with the dynamic source routing (DSR) protocol for making the protocol more secure. We thoroughly analyze the DSR protocol and generate the performance matrices for the data pertaining to packets sent, packets received, packets loss, and throughput. We also analyze the outcome attained from the improvised trust establishment scheme by using the three algorithm implementations in NS2 simulator for detecting and preventing various types of attacks.

SOURCE PARAMETERS of CRIMEAN-BLACK SEA EARTHQUAKES in 2015

The spectral and dynamic source parameters (М0, r0, , , ησ, , u, Eu and Mw) of 16 Crimean earthquakes with КП=6.5–10.8, restored by amplitude spectra of compression and shear seismic waves recorded by digital regional seismic stations are analyzed. Approximation of the spectra and source parameters calculation is performed in the framework of the Brune dislocation model. The highest values of dynamic parameters (М0, r0, , , ησ, u, EU и Mw) are obtained for the earthquakes on June 13 and August 16 with h=11 km, h=7 km respectively and КП=10.8, which occurred in the Azov-Kuban and Kerch-Anapa areas. The radiation friction r for all earthquakes had a negative value, pointing to a complex slide of the rupture in the source. Within the whole energy range, the average value of the released stress did not exceed Δσ=8∙105 PA (8 bar) and apparent stress ησ <11∙105 PA (11 bar). For most 2015 earthquakes, the average M0 и r0 values were within the confidence intervals of long-term dependencies M0(КП), r0(КП). The values of r0 were evenly distributed concerning the regression r0(КП) and М0 is mostly located below the average according to М0 (КП). The maximum deviations of M0 from the long-term М0(КП) dependence were obtained for the most strong earthquakes on June 13 and August 16 with КП=10.8. These deviations can be associated with participation in average M0 of the "Sevastopol" station data which give low values of М0 and possible errors in determining the focal depths influencing the choice of environment velocity models to calculate М0. For the most strong earthquake of August 16 with Мw=3.8, which occurred in the Kerch-Anapa region, a solution of focal mechanism was obtained. The earthquake occurred under the action of horizontal latitudinal tensile forces. The type of movement in the source is an oblique normal fault. Both nodal planes have near-meridional (STKNP1=167°) and near-diagonal (STKNP2=336°) strike.

Evaluation of the VOC pollution pattern and emission characteristics during the Beijing resurgence of COVID-19 in summer 2020 based on the measurement of PTR-ToF-MS

A second wave of coronavirus disease 2019 (COVID-19) infections have emerged in summer Beijing, 2020, which provided an opportunity to explore the response of air pollution to reduced human activity. Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) coupled with Positive Matrix Factorization (PMF) source apportionment were applied to evaluate the pollution pattern and capture the detailed dynamic emission characteristics of volatile organic compounds (VOCs) during the representative period with the occurrence of O3 pollution episodes and the Beijing resurgence of COVID-19. The level of anthropogenic VOC was lower than the same period of previous years due to the pandemic and emission reduction measures. More than two-thirds of the observation period were identified as high-O3 days and VOCs exhibited higher mixing ratios and faster consumption rates in the daytime under high-O3 days. The identified VOC emission sources and the corresponding contributions during the whole observation period included: vehicle + fuel (12.41 ± 9.43%), industrial process (9.40 ± 8.65%), solvent usage (19.58 ± 13.46%), biogenic (6.03 ± 5.40%), background + long-lived (5.62 ± 11.37%), and two groups of oxygenated VOC (OVOC) factors (primary emission and secondary formation, 26.14 ± 15.20% and 20.84 ± 14.0%, respectively). Refined dynamic source apportionment results show that the “stay at home” tendency led to decreased emission (- 34.47 ± 1.90 %) and weakened morning peak of vehicle + fuel during the Beijing resurgence. However, growing emission of primary OVOCs (+ 51.10 ± 8.28%) with similar diurnal variation was observed in the new outbreak and afterwards, which might be related to the enhanced usage of pandemic products. The present study illustrated that more stringent VOC reduction measures towards pandemic products should be carried out to achieve the balanced emission abatement of NOx and VOC when adhering to regular epidemic prevention and control measures.

Industry 4.0 whithin Innovation: Bibliometric Analysis

Introduction: the purpose of this research is to analyze the relationships and growth trends of Industry 4.0 within the global universe of current literature on innovation, limited to the subject area of business, administration, and accounting by means of a bibliometric analysis. Method: Scopus is used as a database for the analysis of 513 documents for the period from 1998 to 2021. VOS viewer was used for processing Scopus database and elaboration of figures representing the relationships between samples. Results: the number of documents is exponentially growing, starting with a trend in 2017 and increasing ever since. The most dynamic source is Technological Forecasting And Social Change. The author with most documents is Voight, K. L. with 10, and the most distinguished institution is the University of Johannesburg with 14 documents. The country with more documents is Italy, with 69. According to the database 69 % of the total documents are articles and 23,4 % are conference papers. The number of documents in the area of Business, Management and Accounting, with 513 documents, exceeds by far any other area, representing 42 % of all documents. The funding sponsor with more documents is the National Natural Science Foundations of China with 13 documents. Some of the most updated organizations are Department of Mechanical & Industrial Engineering, The center for digital labor markets. The country with more documents is United Kingdom with 50 documents and 584 citations, followed by United States with 1110 citations. United States has mainly bonds with China, Australia, United Kingdom, Germany and Italy. United Kingdom has mainly bonds with France, Italy, Germany and United States. China’s main relations are Australia, United States, Pakistan, Taiwan, Turkey, Brazil and South Korea. Italy’s main bonds are France, Spain, Brazil, Russian Federation, United Kingdom, Austria and Portugal. It could be determined that countries are mostly grouped in 6 clusters. Conclusion: Although there are not many publications yet, it can be inferred that the term industry 4.0 within the available literature of innovation will keep increasing exponentially over time reinforcing relations between authors, institutions and countries. Based on the current state of literature, the subject area of business, management, and accounting will keep on being the one that encompasses most of the available documents.

Understanding Micropolar Theory in the Earth Sciences II: The Seismic Moment Tensor

Seismic events produced by block rotations about vertical axis occur in many geodynamic contexts. In this study, we show that these rotations can be accounted for using the proper theory, namely micropolar theory, and a new asymmetric moment tensor can be derived. We then apply this new theory to the Kaikōura earthquake (2016/11/14), Mw 7.8, one of the most complex earthquakes ever recorded with modern instrumental techniques. Using advanced numerical techniques, we compute synthetic seismograms including a full asymmetric moment tensor and we show that it induces measurable differences in the waveforms proving that seismic data can record the effects of the block rotations observed in the field. Therefore, the theory developed in this work provides a full framework for future dynamic source inversions of asymmetric moment tensors.

Hygroscopicity of Fresh and Aged Salt Mixtures from Saline Lakes

The high hygroscopicity of salt aerosol particles makes the particles active in aerosol and cloud formations. Inland saline lakes are an important and dynamic source of salt aerosol. The salt particles can be mixed with mineral dust and transported over long distances. During transportation, these particles participate in atmospheric heterogeneous chemistry and further impact the climate and air quality on a global scale. Despite their importance and potential, relatively little research has been done on saline lake salt mixtures from atmospheric perspectives. In this study, we use experimental and model methods to evaluate the hygroscopic properties of saline lake brines, fresh salt aerosol particles, and aged salt aerosol particles. Both original samples and literature data are investigated. The original brine samples are collected from six salt lakes in Shanxi and Qinghai provinces in China. The ionic compositions of the brines are determined and the hygroscopicity measurements are performed on crystallized brines. The experimental results agree well with theoretical deliquescence relative humidity (DRH) values estimated by a thermodynamic model. The correlations between DRHs of different salt components and the correlations between DRHs and ionic concentrations are presented and discussed. Positive matrix factorization (PMF) analysis is performed on the ionic concentrations data and the hygroscopicity results, and the solutions are interpreted and discussed. The fresh and aged salt aerosol particles are analyzed in the same way as the brines, and the comparison shows that the aged salt aerosol particles completely alter their hygroscopic property, i.e., transferring from MgCl2− governed to NH4NO3− governed.

Nutrient Pollution and Its Dynamic Source-Sink Pattern in the Pearl River Estuary (South China)

Nutrient enrichment and its quantitative cause-effect chains of the biogeochemical processes have scarcely been documented in the Pearl River Estuary (South China). Field investigations of nutrient samples taken between 1996 and 2018 showed significant differences in nitrogen and phosphorus with times and sites. The concentrations of DIN and DIP gradually increased over the past two decades, with good fitted linear curves (R2 = 0.31 for DIN, R2 = 0.92 for DIP); while the temporal variation in DSi was non-significant. Higher levels of nitrogen and silicate mainly appeared in the upper estuary because of the riverine influence. The phosphorus pollution was accumulated in the northeast (e.g., Shenzhen bay). The aquatic environment was highly sensitive to nutrient pollution and eutrophication risk, which accordingly corresponded to high phytoplankton production and biodiversity. Phosphorus was the limiting factor of phytoplankton growth in this estuary, and more frequently caused the eutrophication risks and blooms. The nutrient pollution was largely influenced by riverine inputs, quantified by PCA-generation, and the contributions of coastal emission and atmospheric deposition were followed. The two-end member mixing model differentiated the physical alterations from the biological activity and identified the dynamic source-sink patterns of nutrient species. Nitrogen and silicate had relatively conservative behaviors in the estuary and phosphate showed an active pattern.