Hi-Val: Iterative Learning of Hierarchical Value Functions for Policy Generation

Task decomposition is effective in manifold applications where the global complexity of a problem makes planning and decision-making too demanding. This is true, for example, in high-dimensional robotics domains, where (1) unpredictabilities and modeling limitations typically prevent the manual specification of robust behaviors, and (2) learning an action policy is challenging due to the curse of dimensionality. In this work, we borrow the concept of Hierarchical Task Networks (HTNs) to decompose the learning procedure, and we exploit Upper Confidence Tree (UCT) search to introduce HOP, a novel iterative algorithm for hierarchical optimistic planning with learned value functions. To obtain better generalization and generate policies, HOP simultaneously learns and uses action values. These are used to formalize constraints within the search space and to reduce the dimensionality of the problem. We evaluate our algorithm both on a fetching task using a simulated 7-DOF KUKA light weight arm and, on a pick and delivery task with a Pioneer robot

Oxidative Dissolution of Lithium and Manganese from Lithium Manganospinel (LiMn 2 O 4 ): Towards Climate-Smart Processes for Critical Metal Recycling

This work reports the oxidative breakdown of the LiMn2O4 structure using alkaline hypochlorite, as a method for recovering both lithium and manganese species. The heterogeneous dissolution rate for this process is monitored through the formation of the permanganate ion. It is found that reaction occurs under activation control, with a barrier that matches that for electron hopping within the spinel. Moreover, this activation barrier is smaller than those observed for typical conventional methods of recovery of lithium or manganese from LiMn2O4; accordingly, the new process is suggested to be climate-smart, despite the low, single-pass, recovery efficiency that results from slow surface kinetics

Happiness, environmental protection and market economy

The manufacturing sector is leaving the West for Asia’s low wages and good working culture. Europe would be better off keeping these manufacturing activities, slowing down wage inflation and what is more, letting a young, cheaper workforce from the East settle down within their borders. This would aid in preserving the diverse economic structure which has been characteristic for Europe.Beside the economic growth there are two more concepts which have turned into the “holy cows” of economics during the last fifty years. One is the need to constantly improve labor productivity and the other is increasing competitiveness of nations. The high labor productivity of some countries, induces severe unemployment in the globalized world. In the other hand it is high time we understood that it is not competition, but cooperation that brings more happiness to humanity.Should we still opt for “happiness” and “sanity”, it is quite obvious that we all should, in economists’ terms, define our individual welfare functions corresponding to our own set of values, staying free from the influence of media, advertisements and fashion. The cornerstone to all this is the intelligent citizen who prefers local goods and services

Can Virialization Shocks be Detected Around Galaxy Clusters Through the Sunyaev-Zel'dovich Effect?

In cosmological structure formation models, massive non-linear objects in the process of formation, such as galaxy clusters, are surrounded by large-scale shocks at or around the expected virial radius. Direct observational evidence for such virial shocks is currently lacking, but we show here that their presence can be inferred from future, high resolution, high-sensitivity observations of the Sunyaev-Zel'dovich (SZ) effect in galaxy clusters. We study the detectability of virial shocks in mock SZ maps, using simple models of cluster structure (gas density and temperature distributions) and noise (background and foreground galaxy clusters projected along the line of sight, as well as the cosmic microwave background anisotropies). We find that at an angular resolution of 2'' and sensitivity of 10 micro K, expected to be reached at ~ 100 GHz frequencies in a ~ 20 hr integration with the forthcoming ALMA instrument, virial shocks associated with massive M ~ 10^15 M_Sun clusters will stand out from the noise, and can be detected at high significance. More generally, our results imply that the projected SZ surface brightness profile in future, high-resolution experiments will provide sensitive constraints on the density profile of cluster gas.Comment: 15 pages, submitted to Ap

Synthesis and structure of novel ferrocene-containing β-carbolines including polycondensed derivatives with the elements of planar-, central- and conformational chirality

Employing tryptamine or tryptophane methylester hydrochloride and (Sp)-2-formylferrocene-1- carboxylate as precursors by means of PicteteSpengler reactions and subsequent intramolecular acylation effected by cyanuricfluoride or carbonyldiimidazole (CDI), the first representatives of ferrocenecontaining b-carboline derivatives including polycyclic ferroceno/fused lactames, were prepared. In the course of CDI-mediated tandem cyclization of a tryptophane-derived carboxyferrocenyl-substituted bcarboline, a ring enlargement simultaneously taking place with the loss of the h5-C5H5Feþ fragment of the fused ferrocene moiety, effected by the coordinating imidazole released from the reagent, led to a 4Hcyclopenta[ 7,8]azonino[5,4-b]indole as a minor product. The constitution and relative configuration of the new compounds with the elements of planar-, central- and conformational chirality were established by NMR methods including HMQC, HMBC and NOESY measurements supported by DFT modeling studies

Thermal, viscoelastic and mechanical behavior of polypropylene with synthetic boehmite alumina nanoparticles

Effects of nanofiller concentration and surface treatments on the morphology, thermal, viscoelastic and mechanical behaviors of polypropylene copolymer (PP)/boehmite alumina (BA) nanocomposites were investigated. Both untreated and treated BA particles with octylsilane (OS) and with sulphonic acid compound (OS2) were added up to 10 wt% to produce nanocomposites by melt mixing followed by film blow molding and hot pressing. Dispersion of BA was studied by scanning electron microscopy. Differential scanning calorimetry and wide-angle X-ray scattering were adopted to detect changes in the crystalline structure of PP. Thermooxidative degradation of the nanocomposites was assessed by thermogravimetrical analysis. Dynamic mechanical analysis served for studying the viscoelastic, whereas quasi-static tensile, creep and Elmendorf tear tests were used to detect changes in the mechanical performance. BA nanoparticles were finely dispersed in PP up to 10 wt%, even when they were not surface modified. The resistance to thermal degradation was markedly improved by BA nanomodification. Changes observed in the mechanical properties were attributed to BA dispersion, filler/matrix interactions and related effects because the crystalline characteristics of the PP matrix practically did not change with BA modification