Theory of free surface flow over rough seeping beds

A new theory is developed for the steady free surface flow over a horizontal rough bed with uniform upward seepage normal to the bed. The theory is based on the Reynolds averaged Navier-Stokes (RANS) equations applied to the flow domain that is divided into a fully turbulent outer layer and an inner layer (viscous sublayer plus buffer layer), which is a transition zone from viscous to turbulent regime. In the outer layer, the Reynolds stress far exceeds viscous shear stress, varying gradually with vertical distance. Near the free surface, the velocity gradient in vertical direction becomes lesser giving rise to wake flow. On the other hand, in the composite inner layer close to the bed, the viscous shear stress exists together with the turbulent stress. Thus, for the outer layer, a logarithmic law having modified coefficients from the traditional logarithmic law is obtained for the streamwise velocity, whereas for the inner layer, a fifth-degree polynomial including effective height of protrusions holds. The exact velocity expressions for inner and outer layer, which contain principal terms in addition to infinitesimally small terms, are in agreement with the experimental data obtained from laboratory measurements through an acoustic Doppler velocimeter. The experiments were run on two conditions of no seepage and a low upward seepage. Expressions for the Reynolds stress are also derived and computed for validation by the experimental data

A Reynolds Averaged Theory of Turbulent Shear Flows over Stable Sinusoidal Beds and Formation of Sand Waves

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Optimal Vehicle Charging in Bilevel Power-Traffic Networks via Charging Demand Function

Electric vehicle (EV) charging couples the operation of power and traffic networks. Specifically, the power network determines the charging price at various locations, while EVs on the traffic network optimize the charging power given the price, acting as price-takers. We model such decision-making processes by a bilevel program, with the power network at the upper-level and the traffic network at the lower-level. However, since the two networks are managed by separate entities and the charging expense term, calculated as the product of charging price and charging demand, is nonlinear. Solving the bilevel program is nontrivial. To overcome these challenges, we derive the charging demand function using multiparametric programming theory. This function establishes a piecewise linear relationship between the charging price and the optimal charging power, enabling the power network operator to manage EV charging power independently while accounting for the coupling between the two networks. With the derived function, we are also able to replace the nonlinear charging expense term with a piecewise quadratic one, thus guaranteeing solution optimality. Our numerical studies demonstrate that different traffic demands can have an impact on charging patterns and the power network can effectively incentivize charging at low-price nodes through price setting.Comment: submitted to IEEE Transactions on Smart Gri

Turbulence in mobile-bed streams

This study is devoted to quantify the near-bed turbulence parameters in mobile-bed flows with bed-load transport. A reduction in near-bed velocity fluctuations due to the decrease of flow velocity relative to particle velocity of the transporting particles results in an excessive near-bed damping in Reynolds shear stress (RSS) distributions. The bed particles are associated with the momentum provided from the flow to maintain their motion overcoming the bed resistance. It leads to a reduction in RSS magnitude over the entire flow depth. In the logarithmic law, the von Kármán coefficient decreases in presence of bed-load transport. The turbulent kinetic energy budget reveals that for the bed-load transport, the pressure energy diffusion rate near the bed changes sharply to a negative magnitude, implying a gain in turbulence production. According to the quadrant analysis, sweep events in mobile-bed flows are the principal mechanism of bed-load transport. The universal probability density functions for turbulence parameters given by Bose and Dey have been successfully applied in mobile-bed flows

Plant-Derived SAC domain of PAR-4 (Prostate Apoptosis Response 4) Exhibits Growth Inhibitory Effects in Prostate Cancer Cells

The gene Par-4 (Prostate Apoptosis Response 4) was originally identified in prostate cancer cells undergoing apoptosis and its product Par-4 showed cancer specific pro-apoptotic activity. Particularly, the SAC domain of Par-4 (SAC-Par-4) selectively kills cancer cells leaving normal cells unaffected. The therapeutic significance of bioactive SAC-Par-4 is enormous in cancer biology; however, its large scale production is still a matter of concern. Here we report the production of SAC-Par-4-GFP fusion protein coupled to translational enhancer sequence (5′ AMV) and apoplast signal peptide (aTP) in transgenic Nicotiana tabacum cv. Samsun NN plants under the control of a unique recombinant promoter M24. Transgene integration was confirmed by genomic DNA PCR, Southern and Northern blotting, Real-time PCR, and Nuclear run-on assays. Results of Western blot analysis and ELISA confirmed expression of recombinant SAC-Par-4-GFP protein and it was as high as 0.15% of total soluble protein. In addition, we found that targeting of plant recombinant SAC-Par-4-GFP to the apoplast and endoplasmic reticulum (ER) was essential for the stability of plant recombinant protein in comparison to the bacterial derived SAC-Par-4. Deglycosylation analysis demonstrated that ER-targeted SAC-Par-4-GFP-SEKDEL undergoes O-linked glycosylation unlike apoplast-targeted SAC-Par-4-GFP. Furthermore, various in vitro studies like mammalian cells proliferation assay (MTT), apoptosis induction assays, and NF-κB suppression suggested the cytotoxic and apoptotic properties of plant-derived SAC-Par-4-GFP against multiple prostate cancer cell lines. Additionally, pre-treatment of MAT-LyLu prostate cancer cells with purified SAC-Par-4-GFP significantly delayed the onset of tumor in a syngeneic rat prostate cancer model. Taken altogether, we proclaim that plant made SAC-Par-4 may become a useful alternate therapy for effectively alleviating cancer in the new era

Addressing Response Time and Video Quality in Remote Server Based Internet Mobile Gaming

Abstract—A new remote server based gaming approach, where the responsibility of executing the gaming engines is put on remote servers instead of the mobile devices, has the potential for enabling mobile users to play the same rich Internet games available to PC users. However, the mobile gaming user experience may be limited by risks of unacceptably high response time, and low gaming video quality, as gaming control commands, and the resulting gaming video, have to travel through wireless networks characterized by high bandwidth fluctuations, latency and packet loss. In this paper, we propose a set of application layer optimization techniques to ensure acceptable gaming response time and video quality in the remote server based approach. The techniques include downlink gaming video rate adaptation, uplink delay optimization, and client play-out delay adaptation. Experiments conducted on a commercial HSDPA network demonstrate that the proposed optimization techniques can make the remote server based approach feasible, allowing rich Internet games to be played on mobile devices, while ensuring acceptable user experience. devices, as it will eliminate the need for mobile devices to download and execute the memory and computation intensive gaming engines. The Remote Server Based Mobile Gaming (RSBMG) approach, including the associated control and data flows, is shown in Figure 1. It extends the traditional game content server with two additional components: game engine servers and game streaming servers. The mobile user issues a game command on the mobile device, which is delivered to the remote gaming server using the wireless uplink channel, and accepted by the game content server. The game engine server then loads the client’s account information and game data from the content server, and starts to process the game logic and user data to render the raw game video. The generated raw game video is encoded by the game streaming server, and finally sent to the mobile client via the downlink wireless connection. I

Comminution features in an impact hammer mill

A systematic study on the comminution of a soft (coal) and a hard (iron ore) material is carried out to inves-tigate the bulk comminution features of the hammer mill. The effect of the feed rate and the rotor speed on the mill efficiency in terms of reduction ratio, energy expendit-ure, fines produced and median size is investigated. High reduction ratios are obtained under all conditions. The hammer mill products are observed to exhibit Rosin–Rammler type size distribution and are invariably self preserving. A high rotor speed with a low to moderate feed rate is found to give better performance of the mill. An exponential dependence of the median size on the quantity of fines generated is established for the mill product. The data indicated that the reduction ratio and the specific energy expenditure are linearly related, the slope of which is inversely related to the Bond Index of the material. The energy expenditure goes into creating new surfaces and overcoming the elastic strain energy of the cracked surface. The quantity of fines generated in the mill can reflect the degree of attrition in the millwhich is an indirect measure of the millwear. It is established that good performance of the mill can be achieved even for the hard materials by keeping the wear at a low level. It is suggested that an impact hammer mill can be used for the comminution of harder materials under controlled conditions

Modeling and Characterizing User Experience in a Cloud Server Based Mobile Gaming Approach

Abstract—With the evolution of mobile devices and networks, and the growing trend of mobile Internet access, rich, multi-player gaming using mobile devices, similar to PC-based Internet games, has tremendous potential and interest. However, the current client-server architecture for PC-based Internet games, where most of the storage and computational burden of the game lies with the client device, does not work with mobile devices, constraining mobile gaming to either downloadable, single player games, or very light non-interactive versions of the rich multi-player Internet games. In this paper, we study a cloud server based approach, termed Cloud Mobile Gaming (CMG), where the burden of executing the gaming engines is put on cloud servers, and the mobile devices just communicate the users ’ gaming commands to the servers. We analyze the factors affecting the quality of user experience using the CMG approach, including the game genres, video encoding factors, and the conditions of the wireless network. Based on the above analysis, we develop a model for Mobile Gaming User Experience (MGUE), and develop a prototype for real-time measurement of MGUE that can be used in real networks. We validate MGUE model using controlled subjective testing, and then use it to characterize user experience achievable using the CMG approach in wireless networks. I

Optimizing Resource Utilization and Testability Using Hot Potato Techniques

This paper introduces hot potato high level synthesis transformation techniques. These techniques add deflection operations in a computation in such a way that a specific goal is optimized. We demonstrate how the requirements for two important components of the final implementation cost, registers and interconnects, are significantly reduced using new technique. It is also demonstrated how hot potato techniques can be effectively used during high level synthesis to minimize the partial scan overhead to make the synthesized design testable