Torsion free instanton sheaves on the blow-up of P3\mathbb{P}^{3} at a point

We consider an extension of the instanton bundles definition, given by Casnati-Coskun-Genk-Malaspina, for Fano threefolds, in order to include non locally-free ones on the blow-up $\widetilde{\mathbb{P}^{3}},$ of the projective $3-$space at a point. With the proposed definition, we prove that any reflexive instanton sheaf must be locally free, and that the strictly torsion free instanton sheaves have singularities of pure dimension $1.$ We construct examples and study their $\mu-$stability. Furthermore, these sheaves will play a role in (partially) compactifying the t'Hooft component of the moduli space of instantons, on $\widetilde{\mathbb{P}^{3}}.$ Finally, examples of these are shown to be smooth and smoothable.Comment: 22page

Stylistic Analysis of Roald Dahl’s Cinderella

The paper presents a stylistic analysis of a rhyme, Cinderella, taken from Dahl’s rhyme collection, Revolting Rhymes. Roald Dahl is famous for his ability in creating extraordinary stories, in which linguistic elements, such as sounds and words, are manipulated to create an amusing story that has an unpredictable plot. The discussion covers an analysis of the narrative structure and the linguistic style applied in the rhyme, together with the discussion of the author’s purpose of applying such style. From the analysis it is found out that the style Dahl applies in the rhyme is especially useful for foregrounding

S-wave and p-wave scattering in a cold gas of Na and Rb atoms

Using improved experimentally based $X{}^1\Sigma^+$ and $a{}^3\Sigma^+$ molecular potentials of NaRb, we apply the variable phase method to compute new data for low energy scattering of $^{23}$Na atoms by $^{85}$Rb atoms and $^{87}$Rb atoms. These are the scattering lengths and volumes, numbers of bound states and effective ranges, which we use to obtain the low energy spin-change cross section as functions of the system temperature and the isotope masses. From an analysis of the contributions of s-wave and p-wave scatterings to the elastic cross section we estimate temperatures below which only s-wave scattering is dominant. We compare our quantal results to data obtained from the semiclassical approximation. We supply evidence for the existence of a near zero energy p-wave bound state supported by the singlet molecular potential.Comment: The article contains additional material and data (see abstract

Penerapan Konsep Exchanging Experience Untuk Menghapus Pelabelan Terhadap Difabel

Lebih dari satu milyar manusia di dunia hidup dengan keterbatasan fisik atau mental yang menghambatnya untuk beraktivitas, atau yang disebut dengan difabel. Difabel di Indonesia belum memiliki kesempatan untuk mengembangkan diri, terbukti dengan rendahnya tingkat pendidikan, kemampuan ekonomi, dan partisipasi sosial difabel. Salah satu faktor penyebabnya adalah stigma yang berkembang di masyarakat yang cenderung meremehkan difabel. Respon secara arsitektural untuk menghapus pelabelan pada difabel adalah dengan menghadirkan arsitektur berkonsep pertukaran pengalaman (exchanging experience), khususnya pengalaman indra, antara difabel dan non-difabel. Permasalahan desain yang muncul adalah bagaimana penerapan konsep tersebut dalam arsitektur, baik pada program ruang, interior, fasad, hingga ruang luar. Untuk menghadirkan konsep tersebut digunakan metode Rationalist Approaches yang membutuhkan pengetahuan di bidang lain sebagai dasar, dalam hal ini terkait indra dan psikologi pengguna. Dengan metode tersebut, arsitektur yang hadir mengundang penggunanya lebih peka dalam mengeksplorasi indra. Elemen-elemen arsitektur seperti dinding, lantai, hingga ramp memberikan pengalaman pada indra manusia melalui pemilihan dan pengaplikasian material dengan karakteristik tertentu

Continuity and boundary conditions in thermodynamics: From Carnot's efficiency to efficiencies at maximum power

[...] By the beginning of the 20th century, the principles of thermodynamics were summarized into the so-called four laws, which were, as it turns out, definitive negative answers to the doomed quests for perpetual motion machines. As a matter of fact, one result of Sadi Carnot's work was precisely that the heat-to-work conversion process is fundamentally limited; as such, it is considered as a first version of the second law of thermodynamics. Although it was derived from Carnot's unrealistic model, the upper bound on the thermodynamic conversion efficiency, known as the Carnot efficiency, became a paradigm as the next target after the failure of the perpetual motion ideal. In the 1950's, Jacques Yvon published a conference paper containing the necessary ingredients for a new class of models, and even a formula, not so different from that of Carnot's efficiency, which later would become the new efficiency reference. Yvon's first analysis [...] went fairly unnoticed for twenty years, until Frank Curzon and Boye Ahlborn published their pedagogical paper about the effect of finite heat transfer on output power limitation and their derivation of the efficiency at maximum power, now known as the Curzon-Ahlborn (CA) efficiency. The notion of finite rate explicitly introduced time in thermodynamics, and its significance cannot be overlooked as shown by the wealth of works devoted to what is now known as finite-time thermodynamics since the end of the 1970's. [...] The object of the article is thus to cover some of the milestones of thermodynamics, and show through the illustrative case of thermoelectric generators, our model heat engine, that the shift from Carnot's efficiency to efficiencies at maximum power explains itself naturally as one considers continuity and boundary conditions carefully [...]