A secure and lightweight drones-access protocol for smart city surveillance

The rising popularity of ICT and the Internet has enabled Unmanned Aerial Vehicle (UAV) to offer advantageous assistance to Vehicular Ad-hoc Network (VANET), realizing a relay node's role among the disconnected segments in the road. In this scenario, the communication is done between Vehicles to UAVs (V2U), subsequently transforming into a UAV-assisted VANET. UAV-assisted VANET allows users to access real-time data, especially the monitoring data in smart cities using current mobile networks. Nevertheless, due to the open nature of communication infrastructure, the high mobility of vehicles along with the security and privacy constraints are the significant concerns of UAV-assisted VANET. In these scenarios, Deep Learning Algorithms (DLA) could play an effective role in the security, privacy, and routing issues of UAV-assisted VANET. Keeping this in mind, we have devised a DLA-based key-exchange protocol for UAV-assisted VANET. The proposed protocol extends the scalability and uses secure bitwise XOR operations, one-way hash functions, including user's biometric verification when users and drones are mutually authenticated. The proposed protocol can resist many well-known security attacks and provides formal and informal security under the Random Oracle Model (ROM). The security comparison shows that the proposed protocol outperforms the security performance in terms of running time cost and communication cost and has effective security features compared to other related protocols

Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

Investigation of major factors that cause diesel NOx formation and assessment of energy and exergy parameters using e-diesel blends

The study investigated the key factors that influence the formation of diesel nitrogen oxides (NOx) ethanol–diesel (e-diesel) blends. In the first phase of this investigation, a thermodynamic model was developed to simulate and analyse the different parameters that affect the NOx formation. GT-Power was used to develop the model. ANSYS was also used to compare the results of GT-Power. The simulated (GT-Power and ANSYS) data of cylinder pressure was validated with experimental in-cylinder pressure data. For the 1-D model development, a 4-cylinder diesel engine with a compression ratio of 22.6 was chosen. The engine speed was differed from 1400 rpm to 2400 rpm; the injection timing was varied from 30° before top dead centre (BTDC) to 20° after top dead centre (ATDC), the inlet air temperature were changed from 293 K to 393 K, and the injected masses were ranged from 32 mg to 92 mg. Also, the energetic and exergetic parameters with respect to oxygen ratio and equivalence ratio were investigated. For this investigation, three ethanol blends and neat diesel fuel were used. The first blend was prepared with 10% ethanol and 90% diesel (E10), Similarly, the E20, E30 were made. The simulated data indicated that higher in-cylinder combustion temperature, inlet temperature, injected mass, and advanced injection timing were the principal causes for higher NOx formation. Interesting to note that among the four fuels, all three blends showed less NOx relative to neat diesel. The energy and exergy parameters with oxygen ratio show insignificant variations among the four fuels