Four nucleon pickup studies on medium-weight and heavy nuclei with the (d, 6Li) reaction

This thsis summarizes several years of experimental work performed at the "Kernfysisch Versneller Instituut" in Groningen. Medium-weight and heavy nuclei were studied with the (d,6Li) reaction at a bombarding energy of MeV. The present study will focus on nuclei with mass A > 70 with an emphasis on nuclei in the A = 100 mass region. ... Zie: Summar

Towards simultaneous electrical and optical investigation of BLMS using a novel microfluidic device

We firstly describe the influence of the phospholipid (PL) composition of bilayer lipid membrane on their electrical properties: (i) the more unsaturations in the tail, the earlier the BLM breakdown and (ii) the bulkier the head group, the less stable the membrane. Secondly, we design and fabricate novel devices that couple such electri-cal characterization to optical investigation and that enable the preparation of asym-metrical membranes: a “macro” device including a drilled PMMA plate as well as microfluidic device consisting of a glass-teflon foil-glass sandwich

How high schools teach quantum physics – a cross-national analysis of curricula in secondary education

Quantum physics (QP) changed our worldview, it brought us modern electronic devices, and its almost mythical image fascinates. Although QP is relatively new in secondary education, it is now part of the national curricula of many countries. To understand the current state of QP content in high schools, we scrutinised upper secondary school physics curriculum documents in 15 countries. In these countries, we identified a similar core curriculum of QP which contains the following seven main categories: discrete atomic energy levels, interactions between light and matter, wave-particle duality, de Broglie wavelength, technical applications, Heisenberg's uncertainty principle, and the probabilistic nature of QP. We also found differences in the focus of the listed topics of individual countries, which indicate different views on teaching QP. The thematic focus of QP items is related to the underlying goal of science education and to the way students' knowledge is tested. This overview shows which QP content is generally feasible at a secondary level and which pedagogical perspectives are possible. Therefore this study might lead to reflections on existing QP curricula, and inspire countries that do not have QP in their curriculum yet

Performance analysis of a dynamic query processing scheme

Traditional query optimizers produce a fixed query evaluation plan based on assumptions about data distribution and processor workloads. However, these assumptions may not hold at query execution time. In this paper, we propose a dynamic query processing scheme and we present the performance results obtained by simulation of a queueing network model of the proposed software architecture

A key role for stimulus-specific updating of the sensory cortices in the learning of stimulus-reward associations

Successful adaptive behavior requires the learning of associations between stimulus-specific choices and rewarding outcomes. Most research on the mechanisms underlying such processes has focused on subcortical reward-processing regions, in conjunction with frontal circuits. Given the extensive stimulus-specific coding in the sensory cortices, we hypothesized they would play a key role in the learning of stimulus-specific reward associations. We recorded electrical brain activity (EEG) during a learning-based, decision-making, gambling task where, on each trial, participants chose between a face and a house and then received feedback (gain or loss). Within each 20-trial set, either faces or houses were more likely to predict a gain. Results showed that early feedback processing (~200-1200ms) was independent of the choice made. In contrast, later feedback processing (~1400-1800ms) was stimulus-specific, reflected by decreased alpha power (reflecting increased cortical activity) over face-selective regions. For winning-versus-losing after a face choice, but not after a house choice. Finally, as the reward association was learned in a set, there was increasingly stronger attentional bias towards the more likely winning stimulus, reflected by increasing attentional-orienting-related brain activity and increasing likelihood of choosing that stimulus. These results delineate the processes underlying the updating of stimulus-reward associations during feedback-guided learning, which then guides future attentional allocation and decision making

Повышение эффективности контекстной рекламы в Интернете

Рассмотрены пути повышения эффективности рекламной кампании на площадках поисковых систем. Предложен подход к формированию рабочей группы ключевых слов, используемых в рекламных предложениях, разработан механизм изменения состава группы. Выработаны рекомендации по формированию и коррекции цены предложения на рекламном аукционе Google. Выполнена проверка предложенных решений на основе практических данных коммерческой фирмы, занимающейся контекстной рекламой на площадке поисковой системы.Розглянуто шляхи підвищення ефективності рекламної кампанії на площадках пошукових систем. Запропоновано підхід до формування робочої групи ключових слів, використовуваних у рекламних пропозиціях, розроблений механізм зміни складу групи. Вироблено рекомендації з формування й корекції ціни пропозиції на рекламному аукціоні Google. Виконано перевірку запропонованих рішень на основі практичних даних комерційної фірми, що займається контекстною рекламою на площадці пошукової системи.During article were examined new ways of Internet search system advertising efficiency increasing. Have been suggested method of creation optimal keywords workgroup(which are used in advertising sentences) approach. Have been worked out recommendations for bid fixing and correction. on Google advertising auction. Suggested conceptions were tested and implemented on real busyness information of internet-advertising company, which is mostly concentrated on context advertisin