An operational system for subject switching between controlled vocabularies: A computational linguistics approach

The NASA Lexical Dictionary (NLD), a system that automatically translates input subject terms to those of NASA, was developed in four phases. Phase One provided Phrase Matching, a context sensitive word-matching process that matches input phrase words with any NASA Thesaurus posting (i.e., index) term or Use reference. Other Use references have been added to enable the matching of synonyms, variant spellings, and some words with the same root. Phase Two provided the capability of translating any individual DTIC term to one or more NASA terms having the same meaning. Phase Three provided NASA terms having equivalent concepts for two or more DTIC terms, i.e., coordinations of DTIC terms. Phase Four was concerned with indexer feedback and maintenance. Although the original NLD construction involved much manual data entry, ways were found to automate nearly all but the intellectual decision-making processes. In addition to finding improved ways to construct a lexical dictionary, applications for the NLD have been found and are being developed

Half-life of the electron-capture decay of 97Ru: Precision measurement shows no temperature dependence

We have measured the half-life of the electron-capture (ec) decay of 97Ru in a metallic environment, both at low temperature (19K), and also at room temperature. We find the half-lives at both temperatures to be the same within 0.1%. This demonstrates that a recent claim that the ec decay half-life for 7Be changes by $0.9% +/- 0.2% under similar circumstances certainly cannot be generalized to other ec decays. Our results for the half-life of 97Ru, 2.8370(14)d at room temperature and 2.8382(14)d at 19K, are consistent with, but much more precise than, previous room-temperature measurements. In addition, we have also measured the half-lives of the beta-emitters 103Ru and 105Rh at both temperatures, and found them also to be unchanged.Comment: 6 pages, 6 figure

Locus of control, attributions and impression management in the selection interview

Surprisingly little is known about the ways in which candidates create positive impressions during employment interviews. Three studies are presented which investigate how candidate and interviewer locus of control influence preferences for three categories of explanations proffered by candidates during graduate recruitment interviews. In Study 1, we asked 139 undergraduate students and 37 personnel managers to rate internal-controllable, internal-uncontrollable and externaluncontrollable candidate attributions for hypothetical past events according to the likelihood of each producing a positive impression during a selection interview. Students also completed Rotter's Locus of Control questionnaire and the Interview Behaviour Scales. Students and personnel managers rated internal-controllable attributions most likely to create a positive impression. However, students with an external LoC rated external-uncontrollable explanations and internal-controllable explanations as being equally likely to convey a positive impression. In Study 2 a group of 62 candidates applying for actual positions with a company completed the same attribution questionnaire prior to first-stage interviews. Interviewer ratings of candidate performance correlated positively with ratings of internal-controllable explanations (r =.36, p< .001). In Study 3, a sample of 103 experienced interviewers completed the attribution questionnaire and the WLOC. All interviewers rated internal-controllable attributions most likely to convey a positive impression of a candidate. However, locus of control mediated preference for candidate attributions such that ‘External’ interviewers rated external-uncontrollable attributions significantly more likely to convey a positive impression than ‘Internal’ interviewers. The implications of these findings for impression management and interview selection decisions are discussed

Revisiting the Rigidly Rotating Magnetosphere model for σ\sigma Ori E - II. Magnetic Doppler imaging, arbitrary field RRM, and light variability

The initial success of the Rigidly Rotating Magnetosphere (RRM) model application to the B2Vp star sigma OriE by Townsend, Owocki & Groote (2005) triggered a renewed era of observational monitoring of this archetypal object. We utilize high-resolution spectropolarimetry and the magnetic Doppler imaging (MDI) technique to simultaneously determine the magnetic configuration, which is predominately dipolar, with a polar strength Bd = 7.3-7.8 kG and a smaller non-axisymmetric quadrupolar contribution, as well as the surface distribution of abundance of He, Fe, C, and Si. We describe a revised RRM model that now accepts an arbitrary surface magnetic field configuration, with the field topology from the MDI models used as input. The resulting synthetic Ha emission and broadband photometric observations generally agree with observations, however, several features are poorly fit. To explore the possibility of a photospheric contribution to the observed photometric variability, the MDI abundance maps were used to compute a synthetic photospheric light curve to determine the effect of the surface inhomogeneities. Including the computed photospheric brightness modulation fails to improve the agreement between the observed and computed photometry. We conclude that the discrepancies cannot be explained as an effect of inhomogeneous surface abundance. Analysis of the UV light variability shows good agreement between observed variability and computed light curves, supporting the accuracy of the photospheric light variation calculation. We thus conclude that significant additional physics is necessary for the RRM model to acceptably reproduce observations of not only sigma Ori E, but also other similar stars with significant stellar wind-magnetic field interactions.Comment: 16 pages, 17 figures, accepted for publication in MNRA

Chronoamperometric response at nanoscale liquid–liquid interface arrays

In this work, potential step chronoamperometry (PSCA) was used to study the behaviour of arrays of nanoscale interfaces between two immiscible electrolyte solutions (nanoITIES). The nanoITIES arrays were formed at nanoporous silicon nitride membranes containing 400 nanopores in a hexagonal close-packed arrangement. Three membrane designs, with nanopore radii of 75, 50 and 17 nm, were studied by ion-transfer of tetrapropylammonium cations across the nanopore array-supported water|1,6-dichlorohexane interface. The cell time constants and charging times were determined prior to experimental PSCA. The three membrane designs studied exhibited charging times in the range of 0.08–0.46 s, with the smallest pore configuration (17 nm radius) exhibiting the longest charging time. The experimental steady-state currents were 30–50% lower than of the calculated inlaid disc model currents, due to diffusion zone overlap at adjacent interfaces. The three nano-interface arrays studied also showed response times of 6 ± 1 s, being the time required to reach 95% of the steady-state current

Colloquium: The transport properties of graphene: An introduction

An introduction to the transport properties of graphene combining experimental results and theoretical analysis is presented. In the theoretical description simple intuitive models are used to illustrate important points on the transport properties of graphene. The concept of chirality, stemming from the massless Dirac nature of the low energy physics of the material, is shown to be instrumental in understanding its transport properties: the conductivity minimum, the electronic mobility, the effect of strain, the weak (anti-)localization, and the optical conductivity.Comment: As publishe

Electrochemical Oxidation and Sensing of Methylamine Gas in Room Temperature Ionic Liquids

The electrochemical behaviour of methylamine gas in several room temperature ionic liquids (RTILs), [C2mim][NTf2], [C4mim][NTf2], [C6mim][FAP], [C4mpyrr][NTf2], [C4mim][BF4], and [C4mim][PF6] has been investigated on a Pt microelectrode using cyclic voltammetry. A broad oxidation wave at approximately 3 V, two reduction peaks and another oxidation peak was observed. A complicated mechanism is predicted based on the voltammetry obtained, with ammonia gas as a likely by-product. The currents obtained suggest that methylamine has a high solubility in RTILs, which is important for gas sensing applications. The analytical utility of methylamine was then studied in [C4mpyrr][NTf2] and [C2mim][NTf2]. A linear calibration graph with an R2 value of 0.99 and limits of detection of 33 and 34 ppm were obtained respectively, suggesting that RTILs are favourable non-volatile solvents for the electrochemical detection of highly toxic methylamine gas

Marine Debris Composition On Tasik Ria Beach, Tombariri, Minahasa Regency

Indonesia disebut sebagai kontributor sampah plastik ke laut terbesar kedua di dunia setelah Tiongkok, dengan estimasi 0,48-1,29 juta metrik ton per tahun (Jambeck et al, 2015). Masalah utama dewasa ini adalah kurangnya informasi mengenai pencemaran sampah laut di pantai, khususnya di Sulawesi Utara. Penelitian ini bertujuan untuk mengidentifikasi jenis sampah laut di Pantai Tasik Ria dengan menggunakan metode pengamatan garis transek. Pengamatan sampah laut dilakukan sebanyak 5 kali dengan total 10 transek antara bulan Februari hingga April 2019. Analisis data dilakukan dengan menggunakan perangkat lunak yaitu Microsoft Excel, Statgraphics, dan JMP. Adapun tehnik analisis yang digunakan adalah EDA (Exploratory Data Analysis) dengan pendekatan utama yaitu, GDA (Graphical Data Analysis). Dari berbagai semua jenis sampah yang didapatkan, sampah plastik merupakan yang paling banyak ditemukan yaitu sebanyak 189 item, diikuti kaca 97 item, kayu dan turunannya 11 item, karet 5 item dan terakhir pakaian 2 item. Berdasarkan hasil penelitian, jenis sampah makro merupakan ukuran sampah yang paling banyak ditemukan di lokasi penelitian. Jumlah total makro-debris yang dikumpulkan di sepuluh transek pengamatan adalah sebanyak 316 item dengan bobot total 118,62 gr/m2, sedangkan meso-debris hanya terdapat 6 item dengan bobot total 7,18 gr/m2. Persentase komposisi makro-debris yang terdapat di pantai Tasik Ria adalah plastik (58,15%), kaca (29,85%), logam (6,52%), kayu dan turunannya (3,42%), karet (1,55%) dan pakaian (0,62%). Hasil ini dapat menggambarkan potensi kejadian dimana plastik menjadi komponen sampah laut dominan di pantai, secara khusus di Kecamatan Tombariri, Kabupaten Minahasa

The magnetic field of the B3V star 16 Pegasi

The Slowly Pulsating B3V star 16 Pegasi was discovered by Hubrig (2006) to be magnetic, based on low-resolution spectropolarimetric observations with FORS1 at the VLT. We have confirmed the presence of a magnetic field with new measurements with the spectropolarimeters Narval at TBL, France and Espadons at CFHT, Hawaii during 2007. The most likely period is about 1.44 d for the modulation of the field, but this could not be firmly established with the available data set. No variability has been found in the UV stellar wind lines. Although the star was reported once to show H alpha in emission, there exists at present no confirmation that the star is a Be star.Comment: 2 pages, 4 figures, contrubuted poster at IAU Symposium 259 "Cosmic Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain, November 3-7, 200