Analytic Description of the Motion of a Trapped Ion in an Even or Odd Squeezed State

A completely analytic description is given of the motion of a trapped ion which is in either an even or an odd squeezed state. Comparison is made to recent results on the even or odd coherent states, and possible experimental work is discussed.Comment: LaTeX. 9 pages plus 7 figures, include

Higher-Power Coherent and Squeezed States

A closed form expression for the higher-power coherent states (eigenstates of $a^{j}$) is given. The cases j=3,4 are discussed in detail, including the time-evolution of the probability densities. These are compared to the case j=2, the even- and odd-coherent states. We give the extensions to the "effective" displacement-operator, higher-power squeezed states and to the ladder-operator/minimum-uncertainty, higher-power squeezed states. The properties of all these states are discussed.Comment: 23 pages including 9 figures. To be published in Optics Communication

Mapping Change: An Examination of Curricular Shifts and Collection Impact

Whether adding a new course or ending a program, curricular changes represent a formal notification from the university to the library that it must support. At American University, all curriculum changes require, as part of the approval process, a library review. While these reviews are shared with collection managers, there has never been a systematic review of the effect the changes have had on purchasing and use. One of the most prohibitive factors in undertaking such as review is that curricular changes are often difficult to map to collections because they reflect interdisciplinary adjustments or courses that push the boundary of what one might associate with a subject, such as cooking with chemistry. In this paper, we demonstrate a method of how to use Library of Congress (LOC) subclass terms to index curricular changes and how to map those LOC subclasses to our integrated library system and electronic resource holdings

The effect of subscription video-on-demand on piracy: evidence from a household-level randomized experiment

We partner with a major multinational telecommunications provider to analyze the effect of subscription video-on-demand (SVoD) services on digital piracy. For a period of 45 consecutive days, a group of randomly selected households who used BitTorrent in the past were gifted with a bundle of TV channels with movies and TV shows that could be streamed as in SVoD. We find that, on average, households that received the gift increased overall TV consumption by 4.6% and reduced Internet downloads and uploads by 4.2% and 4.5%, respectively. However, and also on average, treated households did not change their likelihood of using BitTorrent during the experiment. Our findings are heterogeneous across households and are mediated by the fit between the preferences of households in our sample for movies and the content available as part of the gifted channels. Households with preferences aligned with the gifted content reduced their probability of using BitTorrent during the experiment by 18% and decreased their amount of upload traffic by 45%. We also show using simulation that the size of the SVoD catalog and licensing window restrictions limit significantly the ability of content providers to match SVoD offerings to the preferences of BitTorrent users. Finally, we estimate that households in our sample are willing to pay at most $3.25 USD per month to access a SVoD catalog as large as Netflix's in the United States. Together, our results show that, as a stand-alone strategy, using legal SVoD to curtail piracy will require, at the minimum, offering content much earlier and at much lower prices than those currently offered in the marketplace, changes that are likely to reduce industry revenue and that may damage overall incentives to produce new content while, at the same time, curbing only a small share of piracy.info:eu-repo/semantics/acceptedVersio

Influence of Density of Large Stems on the Blocking Probability at Spillways

Dam safety is strongly linked to the probability of occurrence of large floods. Floods can transport large wood (LW) into reservoirs and towards water release structures as spillways. Due to blocking and clogging, LW may significantly influence the discharge capacity of spillways and thus result in a dangerous rise of the water level in the reservoir. For a better assessment of the related risk, the behaviour of LW in contact with hydraulic structures has to be known. Thus the understanding of LW blockage processes at the spillway and the resulting water level rise in the reservoir is important for the safety evaluation of a dam. The aim of the present study is to describe how LW characteristics can influence blocking probabilities at a spillway inlet equipped with piers. By investigating the parameters linked to LW blockage like slenderness and density, or different hydraulic conditions and transport scenarios, it becomes possible to quantify the behaviour and consequences of LW interactions with spillways. Through systematic laboratory experiments, the influence of LW density on blocking probabilities of individual stems is analysed. Experiments were conducted for reservoir approach flow type, implying small magnitudes of reservoir flow velocity. The results were considered statistically as Bernoulli experiments and the methodology applied was a logistic regression. For the combinations explored, a relation between blocking probability and density, among other parameters, is studied

Ensino de Astronomia com aprendizagem baseada em game: o caso Bendegó

In order to innovate the teaching-learning in physics in schools, the current work uses a digital game developed by the author called "The Bendegó Case" which has a playful approach, for the purpose of facilitating the students’ understanding and commitment in relation to the object of knowledge of Basic Level Astronomy, Kepler’s Laws and the Universal Gravitation in two classes of Junior High School in PalmasTO. It were used two methodologies founded on game-based learning, as the flipped classroom and the Toulmin’s argumentation theory in two different moments to acquire, respectively, Digital Culture and Communication, Competences of Base Nacional Comum Curricular (BNCC). The results revealed the students’ commitment in a certain way, very positive because it facilitated the learning of basic concepts of physics when working on the skill to acquire the competences. So the students became more active, because they did not spend most of their time listening only to the teacher, but interacting themselves, that is, playing a leading role in the class.Com o intuito de inovar o ensino-aprendizagem em Física nas escolas, este trabalho utiliza-se de um jogo digital desenvolvido pelo autor chamado "O caso Bendegó" que tem uma abordagem lúdica, com a finalidade de facilitar a compreensão e o engajamento dos estudantes em relação ao Objeto de Conhecimento da Astronomia Básica, Leis de Kepler e Gravitação Universal em duas turmas da 3ª série do Ensino Médio na cidade de Palmas-TO. Foram utilizadas duas metodologias fundamentadas na Aprendizagem Baseada em Games sendo: a Sala de Aula Invertida e a Teoria da Argumentação de Toulmin, em dois momentos diferentes para adquirir, respectivamente, a Cultura Digital e a Comunicação, Competências da Base Nacional Comum Curricular (BNCC). Os resultados revelaram um engajamento, de certa forma muito positivo, pois facilitou o aprendizado de conceitos básicos da física quando trabalhado a habilidade para adquirir as competências. Assim, os estudantes tornaram mais ativos em razão de não passar a maior parte do tempo ouvindo apenas o professor, mas interagindo, ou seja, assumindo o papel de protagonistas na classe