Soliton and periodic wave solutions to the osmosis K(2, 2) equation

In this paper, two types of traveling wave solutions to the osmosis K(2, 2) equation are investigated. They are characterized by two parameters. The expresssions for the soliton and periodic wave solutions are obtained.Comment: 14 pages, 16 figure

NFC Secure Payment and Verification Scheme with CS E-Ticket

As one of the most important techniques in IoT, NFC (Near Field Communication) is more interesting than ever. NFC is a short-range, high-frequency communication technology well suited for electronic tickets, micropayment, and access control function, which is widely used in the financial industry, traffic transport, road ban control, and other fields. However, NFC is becoming increasingly popular in the relevant field, but its secure problems, such as man-in-the-middle-attack and brute force attack, have hindered its further development. To address the security problems and specific application scenarios, we propose a NFC mobile electronic ticket secure payment and verification scheme in the paper. The proposed scheme uses a CS E-Ticket and offline session key generation and distribution technology to prevent major attacks and increase the security of NFC. As a result, the proposed scheme can not only be a good alternative to mobile e-ticket system but also be used in many NFC fields. Furthermore, compared with other existing schemes, the proposed scheme provides a higher security

Nondimensional Wind and Temperature Profiles in the Atmospheric Surface Layer over the Hinterland of the Taklimakan Desert in China

Observed turbulent fluxes, wind, and temperature profiles at Tazhong station over the hinterland of the Taklimakan Desert in China have been analyzed to evaluate empirical parameters used in the profile functions of desert surface layer. The von Kármán constant derived from our observations is about 0.396 in near-neutral stratification, which is in good agreement with many other studies for different underlying surface. In our analysis, the turbulent Prandtl number is about 0.75 in near-neutral conditions. For unstable range, the nondimensional wind and temperature profile functions are best fitted by the exponents of −1/4 and −1/2, respectively. The linear relations still hold for stable stratification in this extremely arid desert. However, the parameters used in their profile functions need to be revised to be applicable for desert surfaces

Soliton, kink and antikink solutions of a 2-component of the Degasperis-Procesi equation

In this paper, we employ the bifurcation theory of planar dynamical systems to investigate the traveling wave solutions of a 2-component of the Degasperis-Procesi equation. The expressions for smooth soliton, kink and antikink solutions are obtained.Comment: 16 pages, 18 figure

Occurrence of legacy and replacement plasticizers, bisphenols, and flame retardants in potable water in Montreal and South Africa

The occurrence of thirty-nine contaminants including plasticizers, bisphenols, and flame retardants in potable water from Montreal and South Africa was analyzed to determine their presence and concentrations in different water sources. In Montreal, five bottled water (BW) brands and three drinking water treatment plants (DWTP) were included. In South Africa, water was sampled from one urban DWTP located in Pretoria, Gauteng, and one rural DWTP located in Vhembe, along with water from the same rural DWTP which had been stored in small and large plastic containers. A combination of legacy compounds, typically with proven toxic effects, and replacement compounds was investigated. Bisphenols, Dechlorane-602, Dechlorane-603, and s-dechlorane plus (s-DP) were not detected in any water samples, and a-dechlorane plus (a-DP) was only detected in one sample from Pretoria at a concentration of 1.09 ng/L. Lower brominated polybrominated diphenyl ethers (PBDE)s were detected more frequently than higher brominated PBDEs, always at low concentrations of <2 ng/L, and total PBDE levels were statistically higher in South Africa than in Montreal. Replacement flame retardants, organophosphate esters (OPEs), were detected at statistically higher concentrations in Montreal's BW (68.56 ng/L), drinking water (DW) (421.45 ng/L) and Vhembe (198.33 ng/L) than legacy PBDEs. Total OPE concentrations did not demonstrate any geographical trend; however, levels were statistically higher in Montreal's DW than Montreal's BW. Plasticizers were frequently detected in all samples, with legacy compounds DEHP, DBP, and replacement DINCH being detected in 100 % of samples with average concentrations ranging from 6.89 ng/L for DEHP in Pretoria to 175.04 ng/L for DINCH in Montreal's DW. Total plasticizer concentrations were higher in Montreal than in South Africa. The replacement plasticizers (DINCH, DINP, DIDA, and DEHA) were detected at similar frequencies and concentrations as legacy plasticizers (DEHP, DEP, DBP, MEHP). For the compounds reported in earlier studies, the concentrations detected in the present study were similar to other locations. These compounds are not currently regulated in drinking water but their frequent detection, especially OPEs and plasticizers, and the presence of replacement compounds at similar or higher levels than their legacy compounds demonstrate the importance of further investigating the prevalence and the ecological or human health effects of these compounds.The Canadian Institutes of Health Research (CIHR) and the Canadian Foundation for Innovation through the John R. Evans Leaders Fund grant,http://www.elsevier.com/locate/scitotenvhj2023School of Health Systems and Public Health (SHSPH