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Multi-level intake structures are used to take the surface water of reservoirs. The changed boundary conditions will certainly make the water hammer phenomenon more complicated. This paper aims to find out the influence and law of the water hammer pressure after setting the stop log gates.

The authors use the computational fluid dynamics method with the adaptive grid technology to stimulate the water hammer phenomenon of the multi-level intake hydropower station. In the analysis, we set several different heights of stop log gates and two representative times in the starting up and shutdown processes to reflect the impact of multi-level intake structures.

The authors find that the setting of the stop log gates will reduce the pressure during the normal operation and will increase the period and amplitude of the water hammer wave, but will not necessarily increase the maximum water hammer pressure during the shutdown process. The relationship between the height of the stop log gates and the amplitude of the water hammer wave is affected by the shutdown time. After setting stop log gates, the depression depth and wave height of the water level in front of the dam increase when the load changes.

The authors study in this paper the water pressure of the multi-level intake hydropower station that has never been studied before and obtain some laws.

Ponders on whether Abraham Flexner was responsible for the change in medical education in North America in the early 20th century, owing to his report of 1910. Tries to demonstrate that medical education in the USA was part of a greater whole of major changes at that time. Concludes, though there was a philanthropic influence, Flexner (who refused to accept credit for change) was not the father of the medical reform plan.

This paper aims to present a design and simulation of electrostatic nanoelectromechanical system (NEMS)-based logic gates using laterally actuated cantilever with double-electrode structure that can implement logic functions, similar to logic devices that are made of solid-state transistors which operates at 5 V.

The analytical modeling of NEMS switch is carried out for finding the pull-in and pull-out voltage based on Euler-Bernoulli’s beam theory, and its numerical simulation is performed using finite element method computer-aided design tool COVENTORWARE.

This paper reports analytical and numerical simulation of basic NEMS switch to realize the logic gates. The proposed logic gate operates on 5 V which suits well with conventional complementary metal oxide semiconductor (CMOS) logic which in turn reduces the power consumption of the device.

The proposed logic gates use a single bit NEMS switch per logic instead of using 6-14 individual transistors as in CMOS. One exclusive feature of this proposed logic gates is that the basic NEMS switch is structurally modified to function as specific logic gates depending upon the given inputs.

The purpose of this paper is to design an out-of-plane micro electro-thermal-compliant actuator based logic gates which work analogously to complementary metal oxide semiconductor (CMOS) based logic gates. The proposed logic gates used a single-bit mechanical micro ETC actuator per logic instead of using 6-14 individual transistors as in CMOS.

A complete analytical modelling is performed on a single ETC vertical actuator, and a relation between the applied voltage and the out-of-plane deflection is derived. Its coupled electro-thermo-mechanical analysis is carried out using micro electro mechanical system (MEMS) CAD tool CoventorWare to illustrate its performance.

This paper reports analytical and numerical simulation of basic MEMS ETC actuator-based logic gates. The proposed logic gate operates on 5 V, which suits well with conventional CMOS logic, which in turn reduces the power consumption of the device.

The proposed logic gates uses a single-bit MEMS ETC actuator per logic instead of using more transistors as in CMOS. The unique feature of this proposed logic gates is that the basic mechanical ETC actuator is customized in its structure to function as specific logic gates depending upon the given inputs.

Truck appointment systems have been applied in critical container ports in the United States due to their potential to improve handling operations. This paper aims to develop a truck appointment system to optimise the total cost experiencing at the entrance of container terminals by managing truck arrivals and the number of service gates satisfying a given level of service.

The approximation of M_t/G/n_t queuing model is applied and integrated into a cost optimisation model to identify (1) the number of arrival trucks allowed at each time slot and (2) the number of service gates operating at each time slot that ensure the average waiting time is less than a designated time threshold. The optimisation model is solved by the Genetic Algorithm and tested with a case study. Its effectiveness is identified by comparing the model's outcomes with observed data and other recent studies.

The results indicate that the developed truck appointment system can provide more than threefold and twofold reductions of the total cost experiencing at the terminal entrance compared to the actual data and results from previous research, respectively.

The proposed approach provides applicably coordinated truck plans and operating service gates efficiently to decrease congestion, emission and expenses.

This study aims to investigate the price effects, if any, of various types of residential developments' security mechanisms.

Previous literature suggests home buyers pay a premium for homes located within gated communities, but no prior study investigates the various levels of community security features often associated with gated communities. This study extends this literature by examining the presence of gates, guards and patrols (individually and in combination) within residential communities. The findings indicate that home prices are significantly higher in communities that have gates, guards, or guards and patrols. In the presence of guards and patrols, however, the premium associated with gates disappears. These results suggest that the previously identified premium for homes in gated communities may be more appropriately interpreted as a premium for enhanced security provided by guards and patrols within the communities.

Prices of homes in communities exhibit premiums for security gates, security guards and security patrols, but the premium associated with security gates is less impactful than security guards and security patrols.

Developers, home buyers, appraisers and other parties should carefully consider neighborhood security features when evaluating home prices in communities.

The presence of security guards and security patrols implies higher home prices in residential communities and are more impactful than security gates alone.

Prior research reports a price premium for homes in gated communities. This study contributes to that literature and finds that the premium associated with security guards and security patrols dominates the mere presence of security gates.

Alley gating schemes have been given impetus by government funding. A simple causal relationship is assumed by the presence of the gates and a reduction in crime and disorder. The post‐implementation research discussed in this article shows that implementation and installation decisions may have unintended consequences for the displacement of problems and the creation of new signal crimes in areas subject to alley gating.

The purpose of this paper is to experimentally and numerically investigate the interference characteristics between two ski-jump jets on the flip bucket in a large dam spillway when two floodgates are running.

The volume of fluid (VOF) method together with the Realizable k-ε turbulence model were used to predict the flow in two ski-jump jets and the free surface motion in a large dam spillway. The movements of the two gates were simulated using a dynamic mesh controlled by a User Defined Function (UDF). The simulations were run using the prototype dam as the field test to minimize errors due to scale effects. The simulation results are compared with field test observations.

The transient flow calculations, accurately predict the two gate discharges compared to field data with the predicted ski-jump jet interference flow pattern similar to the observed shapes. The transient simulations indicate that the main reason for the deflected nappe is the larger opening difference between the two gates as the buttress side gate closes. When both gates are running, the two ski-jump jets interfere in the flip bucket and raise the jet nappe to near the buttress to form a secondary flow on this jet nappe surface. As the gate continues to close, the nappe surface continues to rise and the surface secondary flow become stronger, which deflects the nappe over the side buttress.

A dynamic mesh is used to simulate the transient flow behavior of two prototype running gates. The transient flow simulation clarifies the hydraulics mechanism for how the two ski-jump jets interfere and deflect the nappe.

This paper aims to propose the reversible Feynman and double Feynman gates using quantum-dot cellular automata (QCA) nanotechnology with minimum QCA cells and latency which minimizes the circuit area with the more energy efficiency.

The core aim of the QCA nanotechnology is to build the high-speed, energy efficient and as much smaller devices as possible. This brings a challenge for the designers to construct the designs that fulfill the requirements as demanded. This paper proposed a new exclusive-OR (XOR) gate which is then used to implement the logical operations of the reversible Feynman and double Feynman gates using QCA nanotechnology.

QCA designer-E has been used for the QCA designs and the simulation results. The proposed QCA designs have less latency, occupy less area and have lesser cell count as compared to the existing ones.

The latencies of the proposed gates are 0.25 which are improved by 50% as compared to the best available design as reported in the literature. The cell count in the proposed XOR gate is 11, while it is 14 in Feynman gate and 27 in double Feynman gate. The cell count for the proposed designs is minimum as compared to the best available designs.

The purpose of this work is to visualize the flow behaviour in critical sections of a pressurized gating system.

The investigation was carried out using water models of gating system that were designed, invoking the principles of similitude. Water was used as the filling medium, and the manner of flow through various sections of the gating system and the cavity was recorded with a high-speed camera capable of capturing images up to 10,000 frames per second. This was followed by an analysis of the results obtained from each phase. Finally, computer simulations of flow were carried out using commercial software. The manner of filling as observed during experiments and that during simulation were compared so as to draw some useful conclusions on the utility of flow visualization using water models and the capability of software to predict the filling pattern during casting process. It was understood that water models are powerful aids for understanding the intricacies of flow through critical sections of the gating systems.

It was observed that water models are a reliable indicator of the mould-filling process. Further, substantial differences in the filling pattern were observed between water model experiments and filling simulation using commercial software.

The findings are limited to horizontal plate-type castings. Also, the influence of surface roughness in the flow through the runner is not considered.

This work facilitates understanding of the importance of flow visualization on the quality and reliability of castings.