292 research outputs found

    Current-mode Biquadratic Universal Filter Design with Two Terminal Unity Gain Cells

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    A grounded parallel lossy active inductor and two current-mode (CM) universal filters are presented in this paper. All the circuits use two voltage followers (VFs) and a current follower (CF). The parallel lossy active inductor includes a grounded capacitor which is attractive in integrated circuit (IC) technology. The CM universal filters have one input and standard three outputs such as band-pass (BP), low-pass (LP) and high-pass (HP) responses. All-pass and notch outputs can be obtained by adding extra one CF. Suggested structures in this paper can be constructed with commercially available active devices such as AD844s. Non-ideal gain and intrinsic X-terminal parasitic resistor effects are examined. Several computer simulations with SPICE program and experimental results by employing AD844s are drawn to verify theoretical ones

    Application of Differential Transform Method for El Nino Southern Oscillation (ENSO) Model with compared Adomian Decomposition and Variational Iteration Methods

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    We consider two nonlinear El Nino Southern Oscillation (ENSO) model to obtain approximate solutions with differential transform method for the first time. Efficiency, accuracy and error rates of solutions are compared with analytic solution, variational iteration and adomian decomposition solutions on the given tables and figures.Comment: 12 pages, 10 figure

    Aftercare to chemically addicted adolescents: An exploration of their needs

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    Treatment of chemical addiction includes preparation for treatment, formal treatment and aftercare. The latter appears to be a neglected area in service delivery to chemically addicted adolescents, contributing to the high relapse potential following treatment. The current qualitative study aimed at both exploring and describing the aftercare needs of chemically addicted adolescents. The chemically addicted adolescents included in this study received in-patient treatment as well as aftercare, but nonetheless experienced a relapse; necessitating further in-patient treatment. Purposive sampling was implemented to recruit 31 participants between the ages of 14 and 20 years. The sample size was determined by data saturation. Data for this exploratory, descriptive and contextual study were collected by means of narrative inquiry. Tesch’s framework for qualitative data analysis was employed and data verification was conducted through Guba’s model. The findings illustrated a need to attend to adolescents intrapersonal and interpersonal as well as environmental needs following treatment. The results can provide service providers with focus areas to be included in aftercare services to these adolescents.Department of HE and Training approved lis

    Genotypic variation in phosphorus efficiency between wheat cultivars grown under greenhouse and field conditions

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    Phosphorus (P) efficiency (relative growth), which is described as the ratio of shoot dry matter or grain yield at deficient P supply to that obtained under adequate P supply, was compared in 25 winter wheat cultivars grown under greenhouse and field conditions with low and adequate P levels in a P-deficient calcareous soil. Adequate P supply resulted in significant increases in shoot dry weight and grain yield under both experimental conditions. In the greenhouse experiment, the increases in shoot dry weight under adequate P supply (80 mg kg(-1)) were from 0% (cv: C-1252) to 34% (cv: Dagdas). Under field conditions, the cultivars showed much greater variation in their response to adequate P supply (60 kg ha(-1)): the increases in shoot dry weight and grain yield with adequate P supply were between -2% (cv: Sivas-111/33) and 25% (cv: Kirac-66) for shoot dry matter production at the heading stage and between 0% (cv: Kirkpinar-79) and 76% (cv: Kate A-1) for grain yield at maturity. Almost all cultivars behaved totally different in their response to P deficiency under greenhouse and field conditions. Phosphorus efficiency ratios (relative growth) under greenhouse conditions did not correlate with the P efficiency ratios under field conditions. In general, durum wheat cultivars were found to be more P efficient compared with bread wheat cultivars. The results of this study indicated that there is wide variation in tolerance to P deficiency among wheat cultivars that can be exploited in breeding new wheat cultivars for high P deficiency tolerance. The results also demonstrated that P efficiency was expressed differently among the wheat cultivars when grown under greenhouse and field conditions and, therefore, special attention should be paid to growth conditions in screening wheat for P efficiency

    Efektivitas Implementasi Permainan Aung-carbon-card Pada Materi Pelajaran Senyawa Karbon

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    Tujuan dalam penelitian adalah mengetahui keefektifan, tingkat kemudahan dan tingkat ketertarikan siswa penggunaan media permainan Aung-Carbon-Card (ACC) dalam pembelajaran struktur senyawa karbon. Penelitian ini menggunakan jenis penelitian eksperimen. Sampel yang digunakan yakni siswa kelas X IPA-1dianggap sebagai kelompok konrol (KC), kelas X IPA-2 (E1), kelas X IPA-3 (E2) dan kelas IPA-4 (E3) dijadikan kelompok eksperimen. Sumber data penelitian ini diperoleh dari tes, angket dan observasi. Instrumen yang digunakan sebelumnya dilakukan uji instrumen untuk mengetahui validitas dan reliabilitas. Data yangdiperoleh dilakukan uji normalitas data. Uji hipotesis dilakukan dengan perhitungan uji statistik uji T two sampel independent menggunakan SPSS 17. Hasil penelitian diperoleh: 1). Pembelajaran senyawa hidrokarbon menggunakan media permainan kartu ACC lebih efektif dibuktikan pada hasil tes dengan uji T, nilai Thitung > Ttabel. 2) Kartu ACC menarik perhatian siswa dalam mempelajari pokok bahasan senyawa karbon dibuktikan dengan hasil angket persentase siswa yang menyatakan permainan kartu ACC hal yang menarik. Hasil persentase E1 88%, E2 85% dan E3 74%. Hasil perhitungan terhadap respon siswa masing-masing kelas eksperimen terhadap KC Thitung > Ttabel. 3). Media permainan kartu ACC dapat membantu mempermudah siswa dalam mempelajari pokok bahasan senyawa dengan hasil angket persentase siswa yang menyatakan bahwa lebih mudah memahami materi dengan menggunakan ACC E1= 76%, E2 = 85% dan E3 = 81%. 4). Media permainan kartu ACC sesuai dan tepat jika digunakan dibuktikan dengan observasi dengan nilai Thitung > Ttabel

    ‘Fair’ welfare comparisons with heterogeneous tastes: subjective versus revealed preferences

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    Multidimensional welfare analysis has recently been revived by money-metric measures based on explicit fairness principles and the respect of individual preferences. To operationalize this approach, preference heterogeneity can be inferred from the observation of individual choices (revealed preferences) or from self-declared satisfaction following these choices (subjective well-being). We question whether using one or the other method makes a difference for welfare analysis based on income-leisure preferences. We estimate ordinal preferences that are either consistent with actual labor supply decisions or with income-leisure satisfaction. For ethical priors based on the compensation principle, we compare the welfare rankings obtained with both methods. The correlation in welfare ranks is high in general and reranking is insignificant for 77% of the individuals. The remaining discrepancies possibly pertain to a variety of factors including constraints (health issues, labor market rationing), irrational behavior and alternative life choices to the pursuit of well-being. We discuss the implications of using one or the other preference elicitation method for welfare analysis

    Assessment of modulated hot wire method for thermophysical characterization of fluid and solid matrices charged with (nano)particle inclusions

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    Recently we reported on simultaneous thermal conductivity k and thermal diffusivity a measurement of liquids and in particular of nanofluids in a configuration using an ac excited hot wire combined with lock-in detection of the third harmonic (3ω method) [1]. The conductive wire is used as both heater and sensor. The requirements for the asymptotic validity of the line heat source model are fulfilled at low modulation frequencies below a few Hz. The study of the relative sensitivity of signal amplitude and phase to changes in k and a indicates that there is an optimum frequency range for accurate and stable results. We extend by up to two decades the feasible frequency range for 3ω measurements by considering various more elaborate models for the heat transfer between the wire and the fluid. Finally we show that the same ac hot wire method can be applied to soft solid, composite materials. We measured the k enhancement of a poly(ethylene vinyl acetate) EVA polymer matrix charged with various fractions of graphite

    Galaxy And Mass Assembly (GAMA): the 0.013 < z < 0.1 cosmic spectral energy distribution from 0.1 m to 1 mm

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    We use the Galaxy And Mass Assembly survey (GAMA) I data set combined with GALEX, Sloan Digital Sky Survey (SDSS) and UKIRT Infrared Deep Sky Survey (UKIDSS) imaging to construct the low-redshift (z < 0.1) galaxy luminosity functions in FUV, NUV, ugriz and YJHK bands from within a single well-constrained volume of 3.4 × 105 (Mpc h−1)3. The derived luminosity distributions are normalized to the SDSS data release 7 (DR7) main survey to reduce the estimated cosmic variance to the 5 per cent level. The data are used to construct the cosmic spectral energy distribution (CSED) from 0.1 to 2.1 μm free from any wavelength-dependent cosmic variance for both the elliptical and non-elliptical populations. The two populations exhibit dramatically different CSEDs as expected for a predominantly old and young population, respectively. Using the Driver et al. prescription for the azimuthally averaged photon escape fraction, the non-ellipticals are corrected for the impact of dust attenuation and the combined CSED constructed. The final results show that the Universe is currently generating (1.8 ± 0.3) × 1035 h W Mpc−3 of which (1.2 ± 0.1) × 1035 h W Mpc−3 is directly released into the inter-galactic medium and (0.6 ± 0.1) × 1035 h W Mpc−3 is reprocessed and reradiated by dust in the far-IR. Using the GAMA data and our dust model we predict the mid- and far-IR emission which agrees remarkably well with available data. We therefore provide a robust description of the pre- and post-dust attenuated energy output of the nearby Universe from 0.1 μm to 0.6 mm. The largest uncertainty in this measurement lies in the mid- and far-IR bands stemming from the dust attenuation correction and its currently poorly constrained dependence on environment, stellar mass and morphology

    Galaxy And Mass Assembly (GAMA): curation and reanalysis of 16.6k redshifts in the G10/COSMOS region

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    We discuss the construction of the Galaxy And Mass Assembly (GAMA) 10h region (G10) using publicly available data in the Cosmic Evolution Survey region (COSMOS) in order to extend the GAMA survey to z ∼ 1 in a single deg2 field. In order to obtain the maximum number of high precision spectroscopic redshifts we re-reduce all archival zCOSMOS-bright data and use the GAMA automatic cross-correlation redshift fitting code autoz. We use all available redshift information (autoz, zCOSMOS-bright 10k, PRIMUS, VVDS, SDSS and photometric redshifts) to calculate robust best-fitting redshifts for all galaxies and visually inspect all 1D and 2D spectra to obtain 16 583 robust redshifts in the full COSMOS region. We then define the G10 region to be the central ∼1 deg2 of COSMOS, which has relatively high spectroscopic completeness, and encompasses the CHILES VLA region. We define a combined r < 23.0 mag and i < 22.0 mag G10 sample (selected to have the highest bijective overlap) with which to perform future analysis, containing 9861 sources with reliable high-precision VLT-VIMOS spectra. All tables, spectra and imaging are available at http://ict.icrar.org/cutout/G10
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