Factoring Higher-Dimensional Shifts Of Finite Type Onto The Full Shift

A one-dimensional shift of finite type with entropy at least log factors onto the full -shift. The factor map is constructed by exploiting the fact that , or a subshift of , is conjugate to a shift of finite type in which every symbol can be followed by at least symbols. We will investigate analogous statements for higher-dimensional shifts of finite type. We will also show that for a certain class of mixing higher-dimensional shifts of finite type, sufficient entropy implies that is finitely equivalent to a shift of finite type that maps onto the full -shift

Deductive Optimization of Relational Data Storage

Optimizing the physical data storage and retrieval of data are two key database management problems. In this paper, we propose a language that can express a wide range of physical database layouts, going well beyond the row- and column-based methods that are widely used in database management systems. We use deductive synthesis to turn a high-level relational representation of a database query into a highly optimized low-level implementation which operates on a specialized layout of the dataset. We build a compiler for this language and conduct experiments using a popular database benchmark, which shows that the performance of these specialized queries is competitive with a state-of-the-art in memory compiled database system

The Symbolic Dynamics Of Multidimensional Tiling Systems

We prove a multidimensional version of the theorem that every shift of finite type has a power that can be realized as the same power of a tiling system. We also show that the set of entropies of tiling systems equals the set of entropies of shifts of finite type

Very low loss reactively ion etched Tellurium Dioxide planar rib waveguides for linear and non-linear optics

We report on the fabrication and optical properties of the first very low loss nonlinear Tellurite planar rib waveguides ever demonstrated. A new reactive ion etch process based on Hydrogen as the active species was developed to accomplish the low propagation losses. Optical losses below ~0.05dB/cm in most of the NIR spectrum and ~0.10dB/cm at 1550nm have been achieved - the lowest ever reported by more than an order of magnitude and clearly suitable for planar integrated devices. We demonstrate strong spectral broadening of 0.6ps pulses in waveguides fabricated from pure TeO2, in good agreement with simulations

Smoking as an early risk factor for problematic parenting practices

Parenting among those who use non-illicit and more common drugs such as cigarettes remains an understudied area for investigation. Secondary data analyses were performed in 2015 on a prospective study with parent and twin data available on n=3,009 individual members of female twin pairs born between July 1975 and June 1985 identified from Missouri-state birth records. Maternal smoking when the twins were 3+ years of age remained a significant predictor of offspring report of childhood sexual abuse (OR, 1.40; 95% CI, 1.02-1.92) after controlling for key covariates. Given limited public health resources, mothers who smoke during child's preschool years may be targeted for tailored parenting intervention

What Stories Do YP Tell about Their Experience of the Selective Education Process

Very little has been researched about the experiences of young people who undertake selective education tests in the UK. An explorative narrative research design was used to gain a better understanding of the six (age 10- 11) participants’ experiences of sitting the 11+ test and not gaining a place at a grammar school. Questions from the Little Box of Big Questions 2 were used as a tool in semi-structured interviews, in addition to questions devised by the researcher. Each of the participant’s narratives were storied using Clandinin and Connelly’s (2000) notion of human experience that is defined in terms interaction, continuity and situation. The resulting narratives were written in the ‘third-person-omniscient’. This phase of the study was followed by a ‘commentary phase’ that aimed to describe the connectedness between the young people’s stories. Young people discussed aspects of their lives that enabled them to learn at school, and spoke about their future hopes, dreams and aspirations. The research used Positive Psychology, taking a strengths based approach to explore the skills young people thought they brought to their education, skills they would like to develop, and their plans for the future. The research highlighted the impact and importance of parents in young people’s life and how vigilant young people are to ability grouping in schools. The study also sheds a new perspective on the divisive grammar school debate in UK education

Reactive ion etching of tellurite and chalcogenide waveguides using hydrogen, methane, and argon

The authors report in detail on the reactive plasma etching properties of tellurium and demonstrate a high quality etching process using hydrogen, methane, and argon. Very low loss planar ridge waveguides are demonstrated. Optical losses in tellurium dioxide waveguides below 0.1 dB/cm in most of the near infrared region of the electromagnetic spectrum and at 1550 nm have been achieved—the lowest ever reported by more than an order of magnitude and clearly suitable for planar integrated devices. The etch process is also shown to be suitable for chalcogenide glasses which may be of importance in applications such as phase change memory devices and nonlinear integrated optics.The support of the Australian Research Council through its Discovery Grant Program is gratefully acknowledged Grant No. DP070333