VERTICAL AND SLOPED BANK EFFECTS ON DIFFERENT SHIP TYPES

This study employed computer design software to completely draft 3D ship models; then, computational fluid dynamics were used to establish numeric navigation channels and simulate fluid hydrodynamic analysis of ships navigating along shore banks. The parameters considered comprised bank type (vertical and sloped), ship model (two types), velocity, ship-to-bank distance, and navigation time. Figures and tables were used to present the distribution of ship stern eddy current, flow field pressure, and velocity, and the comparison of center of mass deviation, sway force, and yaw moment. Results showed that ships navigating along embankments and channels produced asymmetric flows, which draw the bow away from the shore. Larger ships are substantially more influenced by bank effects than smaller ships. Large sway forces and yaw moments are produced in large ships, drifting the bow away from the bank and the stern towards the bank, increasing the risk of collision with the embankment. From the study results, the characteristics of bank effects are understood and can be used for assisting the safe navigation of ships in restricted waters.

Convergence of City Relational Network, Production Sector Structure, and Regional Development

There is a strong correlation between government intervention and urban production structure in China. Particularly, the outputs of the cities partly come from the economic rent of city relational network (CRN), which is a unique regional policy and administrative hierarchy. In order to analyze the gravity flows of CRN under the nonmarket mechanism, we attempt to build a new gravity model that adopts the production sector. The new gravity produces relational data with direction, which makes it possible to use social network analysis (SNA) and overcome the endogeneity of the linear model. The empirical results show that (1) modified new gravity model can effectively capture the distribution of CRN gravity flows and the convergence of regional development in China, (2) the CRN, which especially stems from the government financial intervention, increases the share of nontradable sectors in cities, and (3) adjustment of the production sector leads to the difference of CRN gravity flows, so asymmetric flows distribution leads to the heterogeneity of regional economic performance. Cities with higher share of nontradables have relatively slower productivity growth in long-term.

Reversing the Industrial Revolution

This chapter argues that energy technologies should be understood in terms of asymmetric global resource transfers and environmental load displacements. The fossil fuel technologies inaugurated during the Industrial Revolution and the renewable energy technologies designed to replace them are similarly entangled with such societal asymmetries. Both represent social strategies of time-space appropriation within a highly unequal world-system generated by the polarizing logic of all-purpose money. The dependence of modern technology on asymmetric flows of embodied labour time, land, matter, and energy is effectively obscured in mainstream economics by the exclusive focus on prices and market mechanisms. Given the land-saving logic of the turn to fossil energy, it is pertinent to ask whether a turn to renewables would imply a return of land constraints. To perceive modern technologies simply as politically neutral instruments for harnessing natural forces, disregarding their demands on land and other resources beyond the technological infrastructure itself, is an example of fetishism.

Viscoelastic nanofluid motion for Homann stagnation-region with thermal radiation characteristics

The problem of Jeffrey’s nanofluid for a modification of Homann’s exterior potential flow in the stagnation region is modeled over a cylindrical disk. The characteristic of electrically conducting nanofluid flow with a time-independent free stream is noted as well. Due to this, a new family of asymmetric flows is created, which mainly depends on the viscoelastic parameter [Formula: see text] magnetic parameter [Formula: see text] and the stress-to strain rate ratio, i.e., [Formula: see text] By deploying Buongiorno’s model and Rosseland’s approximation, the outcomes of the Brownian diffusion, thermophoresis, and solar radiation on the mass and thermal boundary layer are also scrutinized. The conservation laws are remodeled by a similarity transformation, and the governing equations are solved by a builtin program bvp4c in Matlab. Furthermore, a comparison is made between the numerical outcomes and their large- γ asymptotics for wall stresses and displacement thicknesses. It is discovered that due to the impact of Jeffrey’s material parameters and magnetic field, when [Formula: see text] reaches infinity, along the x-axis the two-dimensional displacement thickness and the coefficient of skin friction are closer to their asymptotic values; however, along the y-axis, they exhibit opposite trend. Moreover, the thermal and mass transport is enhanced due to significant contributions of nanofluid conductivity.

A Heuristic Simulation–Optimization Approach to Information Sharing in Supply Chains

The sustainability of the supply chain is possible only if the profitability of all the tiers participating in that supply chain is guaranteed. The profitability of each of these tiers is ensured if information sharing as well as an effective and seamless coordination system are realized between the tiers. This process reduces the influence of an important risk factor known as the bullwhip effect. The purpose of the current study is to determine the necessary information sharing level to optimize the supply chain that has asymmetric flows of input and output values and to examine the effects of information sharing on the order fill rate (OFR) and total inventory cost (TIC) of the supply chain through analysis of variance (ANOVA) testing. In this work, the supply chain was optimized by using the particle swarm optimization (PSO) technique, with an objective function that assumes the maximization of OFR and minimization of TIC. The proposed method showed excellent results in comparing the mean, variance, and coefficient of variation. In addition, the method used the ANOVA test with a 5% significance level to verify the impact of the information sharing level.

Intensity Change of Typhoon Nancy (1961) during Landfall in a Moist Environment over Japan: A Numerical Simulation with Spectral Nudging

Intensity change of tropical cyclones (TCs) as they make landfall is closely linked to sustained periods of high surface winds and heavy precipitation. Few studies have investigated the intensity change of intense TCs that make landfall in middle latitudes such as Japan because few intense typhoons make landfall in middle latitudes. In this study, a numerical simulation of intense Typhoon Nancy (1961) was used to understand the intensity change that occurred when Nancy made landfall in Japan. A spectral nudging technique was introduced to reduce track errors in the simulation. During landfall, the simulated storm exhibited the salient asymmetric structure and rapid eyewall contraction. A tangential wind budget indicated that the maximum wind speed decreased concurrent with an increase in surface friction and advection associated with low-level asymmetric flows. Detailed evolution of the storm’s warm core was analyzed with a potential temperature budget. In the upper part of the warm core centered at a 12-km height, cooling due to ventilation by asymmetric flows and longwave radiation overcame heating due to condensation and shortwave radiation during the contraction of eyewall clouds. In the lower part of the warm core, adiabatic cooling more than offset warm-air intrusions associated with asymmetric flows and condensational heating. The condensation was supplied by an abundance of moisture due to evaporation from the ocean in the well-developed typhoon based on a moisture budget. Sensitivity experiments revealed that environmental baroclinicity in the midlatitudes, orography, and radiative processes made minor contributions to the weakening. The weakening was instead controlled by inner-core dynamics and interactions with land surfaces.

Particle-In-Cell simulations of magnetic reconnection in the presence of a cold shear flow

<p>Our group has done extensive research on the fluid and kinetic effect of cold ion populations on the reconnection process, in an effort to identify factors that can lead to the onset or stopping of magnetic reconnection. Recent fully kinetic studies involving cold protons or oxygen have shown that flows of cold particles significantly modify the reconnection process, and that the nature of this modification is dependent on the configuration of these flows and the constituent ions of the flows. In this study we want to investigate how the reconnection process is affected by a shear flow of cold protons outside of the current sheet, using a 2.5D Particle-In-Cell simulation. The effect of shear flows on magnetic reconnection has investigated earlier, indicating a signifficant modification of the reconnection process. However, it is not clear how these effects will be influenced by the additional scale lengths introduced into the system by a cold ion flow. In particular we want to investigate how the current sheet and diffusion regions are altered by a cold shear flow on a kinetic level, and how the reconnection process is altered on ion scales and beyond. Preliminary results indicate that the shear flow introduces a tilt of the current sheet, which appears to be consistent with earlier studies. Results will be compared to our group’s earlier results involving symmetric and asymmetric flows of cold particles in the inflow regions, as well as existing simulations and observations of magnetic reconnection including warm shear flows.</p>

TIME-VARYING WAVE EFFECTS ON FLOWS AND DYNAMICS AT AN UNSTRATIFIED INLET

Surface gravity waves alter discharge and circulation near and within coastal inlets, affecting the exchange and transport of water masses, nutrients, sediments, and pollutants between inland waters and the ocean. Field observations and numerical simulations suggest that, during storms, wave forcing (radiation-stress gradients) owing to wave dissipation across the ebb shoal can enhance fluxes into the inlet (Bertin et al. 2009; Wargula et al. 2014). As a result, water levels may increase inside the bay (Olabarrieta et al. 2011; Dodet et al. 2013), creating an offshore-directed pressure gradient that may balance onshore fluxes during energetic waves, and may enhance offshore fluxes after the waves decrease. Spatial and tidal variability in water depths on the ebb shoal lead to complex wave breaking patterns that drive spatially and tidally asymmetric flows. Here, field observations and numerical simulations are used to evaluate the effects of waves on discharge and circulation, and the relative importance of wave radiation-stress and pressure gradients at an unstratified inlet during and following energetic waves.