447 research outputs found

    Simulation of water drops on a surface

    Get PDF
    We have designed and implemented a model for rendering and animating water drops moving on a surface under physical effects such as gravity, surface affinity and wind. For improved rendering, the output of the simulation (i.e. the animation sequence of the drops) is recorded for later offline image generation. ©2008 IEEE

    Exchange networks, markets and trust

    Get PDF
    Network-based transactions are attractive as a system for economic exchange because they give network members greater protection against opportunism and exchange hazards compared to more anonymous market transactions. At the same time, net- works restrict the possibilities to exploit economies of scale and other efficiency enhancing properties of markets. When the problem-solving capacity of networks do not make up for the losses generated by not trading with outsiders, trust is important to promote transactions among strangers in the anonymously market. This paper offers an economic analysis of this idea. With the help of a social evolutionary model, it is also demonstrated that mutual trust relations can survive in the anonymous market, even when there is a clear danger of opportunism, and the conventional mechanisms like repetitions and contracts are ruled out

    Terahertz Detection by the Entire Channel of High Electron Mobility Transistors

    Get PDF
    high electron mobility transistors were used as detectors of THz electromagnetic radiation at liquid helium temperatures. Application of high magnetic fields led to the Shubnikov-de Haas oscillations of the detection signal. Measurements carried out with a simultaneous modulation of the intensity of the incident THz beam and the transistor gate voltage showed that the detection signal is determined by the electron plasma both in the gated and ungated parts of the transistor channel. This result is of importance for understanding the physical mechanism of the detection in high electron mobility transistors and for development of a proper theoretical description of this process

    Surgical perspectives from a prospective, nonrandomized, multicenter study of breast conserving surgery and adjuvant electronic brachytherapy for the treatment of breast cancer

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Accelerated partial breast irradiation (APBI) may be used to deliver radiation to the tumor bed post-lumpectomy in eligible patients with breast cancer. Patient and tumor characteristics as well as the lumpectomy technique can influence patient eligibility for APBI. This report describes a lumpectomy procedure and examines patient, tumor, and surgical characteristics from a prospective, multicenter study of electronic brachytherapy.</p> <p>Methods</p> <p>The study enrolled 65 patients of age 45-84 years with ductal carcinoma or ductal carcinoma in situ, and 44 patients, who met the inclusion and exclusion criteria, were treated with APBI using the Axxent<sup>® </sup>electronic brachytherapy system following lumpectomy. The prescription dose was 34 Gy in 10 fractions over 5 days.</p> <p>Results</p> <p>The lumpectomy technique as described herein varied by site and patient characteristics. The balloon applicator was implanted by the surgeon (91%) or a radiation oncologist (9%) during or up to 61 days post-lumpectomy (mean 22 days). A lateral approach was most commonly used (59%) for insertion of the applicator followed by an incision site approach in 27% of cases, a medial approach in 5%, and an inferior approach in 7%. A trocar was used during applicator insertion in 27% of cases. Local anesthetic, sedation, both or neither were administered in 45%, 2%, 41% and 11% of cases, respectively, during applicator placement. The prescription dose was delivered in 42 of 44 treated patients.</p> <p>Conclusions</p> <p>Early stage breast cancer can be treated with breast conserving surgery and APBI using electronic brachytherapy. Treatment was well tolerated, and these early outcomes were similar to the early outcomes with iridium-based balloon brachytherapy.</p

    Effects of mineral amendments on trace elements leaching from pre-treated marine sediment after simulated rainfall events

    Get PDF
    Bauxite extraction by-products (red mud) were used to evaluate their potential ability to stabilize trace elements from dredged and aerated/humidified marine sediment. The investigated by-products were: bauxaline®(BX) that is a press-filtered red mud; bauxsol™(BS) that is a press-filtered red mud previously washed with excess of seawater, and gypsum neutralized bauxaline® (GBX). These materials were separately mixed to dredged composted sediment sample considering 5% and 20% sediment: stabilizer ratios. For pilot experiments, rainfall events were regularly simulated for 3 months. Concentrations of As, Mo, Cd, Cr, Zn, Cu, and Ni were analyzed in collected leachates as well as toxicity. Results showed that Cd, Mo, Zn, and Cu were efficiently stabilized in the solid matrix when 20% of BX, BS, and GBX was applied. Consequently, toxicity of leachates was lower than for the untreated sediment, meaning that contaminants mobility was reduced. A 5% GBX was also efficient for Mo, Zn and Cu stabilization. In all scenarios, As stabilization was not improved. Compared to all other monitored elements, Mo mobility seemed to depend upon temperature-humidity conditions during pilot experiments suggesting the need of further investigations
    corecore