1,035 research outputs found

    Experimental stand for investigation of induction hardening of steel elements

    Get PDF
    The experimental stand for investigation of induction surface hardening of gear wheels was described in the paper. In order to control parameters of the process a specialized equipment for identification of all important process parameters including registration of temperature changes in time and measurements of current intensity was installed. Exemplary results are presented. It is planned that the stand will be used as a demonstrator for a presentation of advantages of modern induction hardening technologies

    Assessing Human Error Against a Benchmark of Perfection

    Full text link
    An increasing number of domains are providing us with detailed trace data on human decisions in settings where we can evaluate the quality of these decisions via an algorithm. Motivated by this development, an emerging line of work has begun to consider whether we can characterize and predict the kinds of decisions where people are likely to make errors. To investigate what a general framework for human error prediction might look like, we focus on a model system with a rich history in the behavioral sciences: the decisions made by chess players as they select moves in a game. We carry out our analysis at a large scale, employing datasets with several million recorded games, and using chess tablebases to acquire a form of ground truth for a subset of chess positions that have been completely solved by computers but remain challenging even for the best players in the world. We organize our analysis around three categories of features that we argue are present in most settings where the analysis of human error is applicable: the skill of the decision-maker, the time available to make the decision, and the inherent difficulty of the decision. We identify rich structure in all three of these categories of features, and find strong evidence that in our domain, features describing the inherent difficulty of an instance are significantly more powerful than features based on skill or time.Comment: KDD 2016; 10 page

    Experimental stand for investigation of induction hardening of steel elements

    Get PDF
    The experimental stand for investigation of induction surface hardening of gear wheels was described in the paper. In order to control parameters of the process a specialized equipment for identification of all important process parameters including registration of temperature changes in time and measurements of current intensity was installed. Exemplary results are presented. It is planned that the stand will be used as a demonstrator for a presentation of advantages of modern induction hardening technologies

    Doxorubicin-loaded iron oxide nanoparticles for glioblastoma therapy: A combinational approach for enhanced delivery of nanoparticles

    Get PDF
    This work is licensed under a Creative Commons Attribution 4.0 International License.Although doxorubicin (DOX) is an effective anti-cancer drug with cytotoxicity in a variety of different tumors, its effectiveness in treating glioblastoma multiforme (GBM) is constrained by insufficient penetration across the blood–brain barrier (BBB). In this study, biocompatible magnetic iron oxide nanoparticles (IONPs) stabilized with trimethoxysilylpropyl-ethylenediamine triacetic acid (EDT) were developed as a carrier of DOX for GBM chemotherapy. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) released DOX within 4 days with the capability of an accelerated release in acidic microenvironments. The DOX-loaded EDT-IONPs (DOX-EDT-IONPs) demonstrated an efficient uptake in mouse brain-derived microvessel endothelial, bEnd.3, Madin–Darby canine kidney transfected with multi-drug resistant protein 1 (MDCK-MDR1), and human U251 GBM cells. The DOX-EDT-IONPs could augment DOX’s uptake in U251 cells by 2.8-fold and significantly inhibited U251 cell proliferation. Moreover, the DOX-EDT-IONPs were found to be effective in apoptotic-induced GBM cell death (over 90%) within 48 h of treatment. Gene expression studies revealed a significant downregulation of TOP II and Ku70, crucial enzymes for DNA repair and replication, as well as MiR-155 oncogene, concomitant with an upregulation of caspase 3 and tumor suppressors i.e., p53, MEG3 and GAS5, in U251 cells upon treatment with DOX-EDT-IONPs. An in vitro MDCK-MDR1-GBM co-culture model was used to assess the BBB permeability and anti-tumor activity of the DOX-EDT-IONPs and DOX treatments. While DOX-EDT-IONP showed improved permeability of DOX across MDCK-MDR1 monolayers compared to DOX alone, cytotoxicity in U251 cells was similar in both treatment groups. Using a cadherin binding peptide (ADTC5) to transiently open tight junctions, in combination with an external magnetic field, significantly enhanced both DOX-EDT-IONP permeability and cytotoxicity in the MDCK-MDR1-GBM co-culture model. Therefore, the combination of magnetic enhanced convective diffusion and the cadherin binding peptide for transiently opening the BBB tight junctions are expected to enhance the efficacy of GBM chemotherapy using the DOX-EDT-IONPs. In general, the developed approach enables the chemotherapeutic to overcome both BBB and multidrug resistance (MDR) glioma cells while providing site-specific magnetic targeting.Canadian Institutes of Health ResearchNatural Science and Engineering Research Council—CanadaNIH R01-NS075374NIH P30-AG035982NIH T32-GM00835

    First-order transitions and triple point on a random p-spin interaction model

    Full text link
    The effects of competing quadrupolar- and spin-glass orderings are investigated on a spin-1 Ising model with infinite-range random pp-spin interactions. The model is studied through the replica approach and a phase diagram is obtained in the limit pp\to\infty. The phase diagram, obtained within replica-symmetry breaking, exhibits a very unusual feature in magnetic models: three first-order transition lines meeting at a commom triple point, where all phases of the model coexist.Comment: 9 pages, 2 ps figures include

    Web-based climate information resources for malaria control in Africa

    Get PDF
    Malaria remains a major public health threat to more than 600 million Africans and its control is recognized as critical to achieving the Millennium Development Goals. The greatest burden of malaria in Africa occurs in the endemic regions where the disease pathogen is continuously present in the community. These regions are characterized by an environment that is conducive to interactions between the Anopheles mosquito, malaria parasites and human hosts, as well as housing of generally poor quality, which offers little protection from mosquito-human contact. Epidemic malaria tends to occur along the geographical margins of endemic regions, when the equilibrium between the human, parasite and mosquito vector populations is occasionally disturbed and a sharp but temporary increase in disease incidence results. When malaria control measures are inadequate, as is the case in much of sub-Saharan Africa, the disease distribution is closely linked with seasonal patterns of the climate and local environment. In the absence of good epidemiological data on malaria distribution in Africa, climate information has long been used to develop malaria risk maps that illustrate the boundaries of 'climatic suitability for endemic transmission.' The best known of these are produced by the Pan-African-based MARA Collaboration. This paper describes the development of additional malaria suitability maps which have been produced in an online, interactive format to enable temporal information (i.e., seasonality of climate conditions) to be queried and displayed along with spatial information. These maps and the seasonal information that they contain should be useful to the malaria control and health service communities for their planning and operational activities

    Corporate Culture and Its Connection with External and Internal Public Relations

    Get PDF
    The main aim of this article is to present the influence of corporate culture on company's stakeholders. This paper signalises the tendency in corporate communication with its internal and external publics. It is focused on two issues: corporate social responsibility and employer branding. Those two categories are consequences of corporate culture model.Głównym celem artykułu jest zaprezentowanie wpływu jaki wywiera charakter kultury korporacyjnej na związanych z przedsiębiorstwem interesariuszy (stakeholders). W artykule zasygnalizowane zostały główne tendencje wyznaczające charakter komunikacji między organizacją a jej wewnętrznym i zewnętrznym otoczeniem. Tekst koncentruje się na dwóch kwestiach: społecznej odpowiedzialności przedsiębiorstwa (corporate social responsibilty) i budowanie wizerunku pracodawcy (employer branding), które zaprezentowane zostały jako efekty określonego modelu kultury organizacyjnej

    Theory of a spherical quantum rotors model: low--temperature regime and finite-size scaling

    Full text link
    The quantum rotors model can be regarded as an effective model for the low-temperature behavior of the quantum Heisenberg antiferromagnets. Here, we consider a dd-dimensional model in the spherical approximation confined to a general geometry of the form Ldd×d×LτzL^{d-d'}\times\infty^{d'}\times L_{\tau}^{z} ( LL-linear space size and LτL_{\tau}-temporal size) and subjected to periodic boundary conditions. Due to the remarkable opportunity it offers for rigorous study of finite-size effects at arbitrary dimensionality this model may play the same role in quantum critical phenomena as the popular Berlin-Kac spherical model in classical critical phenomena. Close to the zero-temperature quantum critical point, the ideas of finite-size scaling are utilized to the fullest extent for studying the critical behavior of the model. For different dimensions 1<d<31<d<3 and 0dd0\leq d'\leq d a detailed analysis, in terms of the special functions of classical mathematics, for the susceptibility and the equation of state is given. Particular attention is paid to the two-dimensional case.Comment: 33pages, revtex+epsf, 3ps figures included submitted to PR

    Interaction-induced Bose Metal in 2D

    Full text link
    We show here that the regularization of the conductivity resulting from the bosonic interactions on the `insulating' (quantum disordered) side of an insulator-superconductor transition in 2D gives rise to a metal with a finite conductivity, σ=(2/π)4e2/h\sigma =(2/\pi) 4 e^2/h, as temperature tends to zero. The Bose metal is stable to weak disorder and hence represents a concrete example of an interaction-induced metallic phase. Phenomenological inclusion of dissipation reinstates the anticipated insulating behaviour in the quantum-disordered regime. Hence, we conclude that the traditionally-studied insulator-superconductor transition, which is driven solely by quantum fluctuations, corresponds to a superconductor-metal transition. The possible relationship to experiments on superconducting thin films in which a low-temperature metallic phase has been observed is discussed.Comment: A figure has been added and the physics has been clarified. To appear in PR
    corecore