On the locus formed by the maximum heights of projectile motion with air resistance

We present an analysis on the geometrical place formed by the set of maxima of the trajectories of a projectile launched in a media with linear drag. Such a place, the locus of apexes, is written in term of the Lambert $W$ function in polar coordinates, confirming the special role played by this function in the problem. In order to characterize the locus, a study of its curvature is presented in two parameterizations, in terms of the launch angle and in the polar one. The angles of maximum curvature are compared with other important angles in the projectile problem. As an addendum, we find that the synchronous curve in this problem is a circle as in the drag-free case.Comment: 7 pages, 6 color eps figures. Synchronous curve added. Typos and style corrected

Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity

Sekolah Luar Biasa Bagian B Di Manado ”Arsitektur Bagi Penyandang Cacat Tunarungu, Mata Yang Mendengar”

Karakteristik yang dimiliki oleh seorang penyandang cacat tunarungu berbeda dengan orang normal. Kekurangan mereka dalam indera pendengaran menyebabkan mereka kesulitan dalam bersekolah dan kesulitan dalam mencari pekerjaan. Di Kota Manado, para penyandang cacat tunarungu hanya bersekolah dengan menumpang di sekolah-sekolah luar biasa yang lain. Hal ini dapat menyebabkan kurang efektifnya sistem pembelajaran bagi anak-anak penyandang cacat tunarungu. Untuk itulah sangat dibutuhkan sarana dan prasarana yang memadai guna untuk mencerdaskan anak-anak penyandang cacat tunarungu. Perancangan Sekolah Luar Biasa bagian B di Manado sangat dibutuhkan oleh anak-anak tunarungu dengan memakai tema ”arsitektur bagi penyandang cacat tunarungu, mata yang mendengar” bertujuan untuk merancang Sekolah Luar Biasa bagian B yang didalamnya mereka tidak saja menuntut ilmu, tapi juga dapat melatih diri mereka sendiri agar ketika berada di dunia luar, mereka tidak dianggap rendah oleh orang-orang normal

Differences among African American Junior High School Students: The Effects of Skin Tone on Ethnic Identity, Self-Esteem and Cross-Cultural Behavior

This article explains the results of a study conducted to assess differences among African American adolescents based on skin tone. It was hypothesized that students would demonstrate differences in self-esteem, ethnic identity and cross-cultural coping strategies based on their skin tones. 144 African American adolescents completed research packets. Results of ANOVA did not suggest any differences among the students on selfesteem, ethnic identity, or cross cultural interaction behaviors. However, significant correlations were found between self-esteem and ethnic identity and between self-esteem and cross cultural interaction behaviors. Implications for counseling and education are discussed

Personal and sub-personal: a defence of Dennett's early distinction

Since 1969, when Dennett introduced a distinction between personal and sub‐personal levels of explanation, many philosophers have used ‘sub‐personal’ very loosely, and Dennett himself has abandoned a view of the personal level as genuinely autonomous. I recommend a position in which Dennett's original distinction is crucial, by arguing that the phenomenon called mental causation is on view only at the properly personal level. If one retains the commit‐’ ments incurred by Dennett's early distinction, then one has a satisfactory anti‐physicalistic, anti‐dualist philosophy of mind. It neither interferes with the projects of sub‐personal psychology, nor encourages ; instrumentalism at the personal level. People lose sight of Dennett’s personal/sub-personal distinction because they free it from its philosophical moorings. A distinction that serves a philosophical purpose is typically rooted in doctrine; it cannot be lifted out of context and continue to do its work. So I shall start from Dennett’s distinction as I read it in its original context. And when I speak of ‘the distinction’, I mean to point not only towards the terms that Dennett first used to define it but also towards the philosophical setting within which its work was cut out

(G)hosting television: Ghostwatch and its medium

This article’s subject is Ghostwatch (BBC, 1992), a drama broadcast on Halloween night of 1992 which adopted the rhetoric of live non-fiction programming, and attracted controversy and ultimately censure from the Broadcasting Standards Council. In what follows, we argue that Ghostwatch must be understood as a televisually-specific artwork and artefact. We discuss the programme’s ludic relationship with some key features of television during what Ellis (2000) has termed its era of ‘availability’, principally liveness, mass simultaneous viewing, and the flow of the television super-text. We trace the programme’s television-specific historicity whilst acknowledging its allusions and debts to other media (most notably film and radio). We explore the sophisticated ways in which Ghostwatch’s visual grammar and vocabulary and deployment of ‘broadcast talk’ (Scannell 1991) variously ape, comment upon and subvert the rhetoric of factual programming, and the ends to which these strategies are put. We hope that these arguments collectively demonstrate the aesthetic and historical significance of Ghostwatch and identify its relationship to its medium and that medium’s history. We offer the programme as an historically-reflexive artefact, and as an exemplary instance of the work of art in television’s age of broadcasting, liveness and co-presence

Magnetic field inversions at 1 AU: comparisons between mapping predictions and observations

Large-scale magnetic field configurations are important for the transport of solar wind strahl electrons, which are suprathermal and directed along the field outward from the Sun. Strahl electrons are routinely used to infer not only the field configurations between the Sun and Earth but also local field structures, i.e., field inversions, where the magnetic field is locally folded back or inverted. Using solar wind data from ACE observations and a 2-D data-driven solar wind model with nonzero azimuthal magnetic field at the solar wind source surface, magnetic field lines are mapped between the Sun and Earth and beyond, in the solar equatorial plane. Standard verification metrics are used to assess, for five solar rotations at different phases of solar cycle 23, the performance of the mapping predictions for observed inversions, which are inferred from solar wind suprathermal electrons and magnetic fields measured by ACE. The probability of detection is consistently ≈0.70 across the different phases. The success ratio, the Hanssen-Kuipers skill score, and the Heidke skill score are ≈0.55–0.70 for the four rotations in the rising, solar maximum, and declining phases, but ≈0.35–0.60 for the rotation near solar minimum, during which almost half of the samples have undetermined field configurations. Our analyses confirm the persistence of inversions throughout solar cycle 23, suggest for most observed inversions a solar/coronal origin at the wind's source surface or below, and predict that inversions should be less common for larger heliocentric distance r ∼> 3 AU than for smaller r