The theoretical study on intermittency and propagation of geodesic acoustic mode in L-mode discharge near tokamak edge

Through a systematically developed theory, we demonstrate that the motion of Instanton identified in Zhang et al(2017 Phys. Plasmas 24 122304) is highly correlated to the intermittent excitation and propagation of geodesic acoustic mode(GAM) that is observed in tokamaks.While many numerical simulations have observed the phenomena, it is the first theory that reveals the physical mechanism behind GAM intermittent excitation and propagation. The preceding work is based on the micro-turbulence associated with toroidal ion temperature gradient mode, and slab-based phenomenological model of zonal flow. When full toroidal effect is introduced into the system, two branches of zonal flow emerge: the torus-modified low frequency zonal flow(TLFZF), and GAM, necessitating a unified exploration of GAM and TLFZF. Indeed, we observe that the transition from the Caviton to Instanton is triggered by a rapid zero-crossing of radial group velocity of drift wave and is found to be strongly correlated with the GAM onset. Many features peculiar to intermittent GAMs, observed in real machines,are thus identified in the numerical experiment. The results will be displayed in figures and in a movie; first for single central rational surface, and then with coupled multiple central rational surfaces. The periodic bursting first shown disappears as being replaced by irregular one, more similar to the intermittent characteristics observed in GAM experiments.     

How Cryptosystems Get Broken

<正>It's all us pleasure to come to China, a great deal of cheerful times already. I hope that we have additional opportunity to meet, talk about cryptography and other components. Today I am going to give a general talk which is not designed for special lists, about how could the systems get     

Convergent and discriminant validity of three measures of stage of change.

The University of Rhode Island Change Assessment (E. A. McConnaughy, J. O. Prochaska, & W. F. Velicer, 1983), the Stages of Change Readiness and Treatment Eagerness Scale (W. R. Miller & J. S. Tonigan, 1996), and the Readiness to Change Questionnaire (S. Rollnick, N. Heather, R. Gold, & W. Hall, 1992) are commonly used multidimensional measures of stage of change. The authors examined the convergent and discriminant validity of drug-use versions of these 3 measures through multitrait-multimethod analysis in a population of indigent, out-of-treatment drug users (N = 377). Agreement in stage-of-change assignment and the relationship between stage of change and drug-use behaviors were also examined. Confirmatory factor analysis suggests that the Stages of Change Readiness and Treatment Eagerness Scale may have questionable convergent validity with the University of Rhode Island Change Assessment and Readiness to Change Questionnaire. There was moderate agreement in stage assignment. Analysis of behavior did provide some support for the construct validity of the measures. The results suggest that these drug-use stage-of-change measures may not be equivalent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Signal amelioration of electrophoretically deposited whole-cell biosensors using external electric fields

This paper presents an integrated whole-cell biochip system where functioning cells are deposited on the solid micro-machined surfaces while specially designed indium tin oxide electrodes that can be used to apply controllable electric fields during various stages; for example during cell deposition. The electrodes can be used also for sensing currents associated with the sensing mechanisms of electrochemical whole-cell biosensors. In this work a new approach integrating live bacterial cells on a biochip using electrophoretic deposition is presented. The biomaterial deposition technique was characterized under various driving potentials and chamber configurations. An analytical model of the electrophoretic deposition kinetics was developed and presented here. The deposited biomass included genetically engineered bacterial cells that may respond to toxic material exposure by expressing proteins that react with specific analytes generating electrochemically active byproducts. In this study the effect of external electric fields on the whole-cell biochips has been successfully developed and tested. The research hypothesis was that by applying electric fields on bacterial whole-cells, their permeability to the penetration of external analytes can be increased. This effect was tested and the results are shown here. The effect of prolonged and short external electric fields on the bioelectrochemical signal generated by sessile bacterial whole-cells in response to the presence of toxins was studied. It was demonstrated that relatively short 10 ms external DC electric pulse improves the performance of bacterial biosensors by 15% relative to un-biased biosensors. The application of prolonged 1 h external alternating electric fields deteriorated the whole-cell performance in the presence of toxins. In this paper we present the electrode apparatus and methods, as well as the characterization results, e.g. signal vs. time and induction factor, of such chips and discussing the highlight and problems of this new concept.     

Enhanced removal of humic acid from water by micelle-montmorillonite composites: Comparison to granulated activated carbon

Removal of humic acid (HA) from water by octadecyltrimethyl-ammonium (ODTMA) micelle–montmorillonite (MMT) composites and by granulated activated carbon (GAC) was studied in dispersion and by filtration. FTIR measurements emphasized that the ODTMA micelle–clay-mineral composite differs from the ODTMA monomer-clay-mineral one. HA adsorption by GAC in dispersion was moderately reduced from 100% initially to 75% with an increase in HA concentrations. In contrast, the fractions adsorbed by the composite increased monotonically with HA concentrations from very low adsorption up to 80%. This effect was explained by the presence of a small concentration of ODTMA monomers in dispersion, which adsorbed on the negatively charged HA and partially neutralized it, or caused charge reversal, which in turn inhibited HA adsorption by the positively charged composite. This effect was verified by mobility measurements and was found to be more pronounced at low HA concentrations. This trend of increase in HA removal with an increase in HA concentration (3 and 10 ppm) was also observed in filtration (50% and 85% removal, respectively), when employing columns of the composite mixed with sand (to improve flow). Throughout the experiment the removal of high HA concentration (10 ppm) by the composite filter remained ~ 80% whereas, the removal by the GAC filter decreased from an initial 80% removal to a complete recovery of the HA (no removal) after the passage of 20 L (200 pore volumes). Upon applying sand of higher quality in the columns the removal of low HA concentrations was nearly complete by the composite column while the GAC only slightly contributed to its removal (for a passage of 100 L (1000 pore volumes)).     

Cooperative TSP

In this paper we introduce and study cooperative variants of the Traveling Salesperson Problem. In these problems a salesperson has to make deliveries to customers who are willing to help in the process. Customer cooperativeness may be manifested in several modes: they may assist by approaching the salesperson, by reselling the goods they purchased to other customers, or by doing both.Several objectives are of interest: minimizing the total distance traveled by all of the participants, minimizing the maximal distance traveled by a participant and minimizing the total time until all of the deliveries are made.All of the combinations of cooperation modes and objective functions are considered, both in weighted undirected graphs and in Euclidean space. We show that most of the problems have a constant approximation algorithm, many of the others admit a PTAS, and a few are solvable in polynomial time. On the intractability side we provide NP-hardness proofs and inapproximability factors, some of which are tight.     

Fuel blend fraction estimation for fuel-flexible combustion control: Uncertainty analysis

“Fuel-flexible combustion control” strategies require accurate fuel composition information. A physics-based fuel blend fraction estimator for lean-burn combustion is used to assess the impact of uncertain variables on the estimator accuracy. For biodiesel blends in a diesel engine, the strategy is shown to be minimally affected by biodiesel feedstock variations, and expected fuel flow and oxygen sensor errors. However, observed airflow estimate errors are expected to lead to large estimator errors. When applied to ethanol blends, the estimator error is lower due to a higher stoichiometric mixture fraction for ethanol, and inherent differences in typical lean-burn gasoline engine operating conditions.     

A review of different pinch techniques

Individuals often pinch with preferred pinch techniques based on their experience and familiarity. However, researchers believe that pinch force exertions are not comparable across different pinch techniques. Hence, it is possible to pinch objects with incompatible pinch techniques during manual handling. This increases risks of developing musculoskeletal disorders. The preceding problem substantiates the need for a comprehensive understanding of definitions, categorisations and capacities of different pinch techniques. Nevertheless, the knowledge on pinch techniques appears to be highly dispersed and not compiled to a level systematic enough for further research. Thus, this review aims to develop a consolidated theoretical groundwork on pinch techniques. It presents an anthology of terminologies, previous findings and concepts underpinning different pinch techniques. While much research is still required, it is believed that an improved understanding on pinch techniques is now within sight, due to, in part, a structured review of their definitions, classifications and capacities.