457 research outputs found

    Aplikasi Market Expert Advisor Pada Currency Market

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    Aktivitas trading membutuhkan tingkat konsistensi pengambilan keputusan yang tinggi dari seorang trader. Namun dalam hal trading, sering kali trader dipengaruhi oleh berbagai macam faktor psikologis, seperti rasa takut, rasa terlalu percaya diri, tidak sabar, emosi, dan sebagainya. Oleh karena itu dibutuhkan suatu aplikasi yang dapat membantu trader untuk mengambil keputusan secara konsiten dalam aktivitas trading tanpa dipengaruhi oleh faktor-faktor psikologis. Aplikasi ini akan dapat memberikan saran kapan untuk melakukan posisi membeli ataupun menjual valas. Selain itu, aplikasi dapat melakukan aktivitas trading secara otomatis sehingga dapat meringankan beban pekerjaan dari seorang trader. Aplikasi ini diuji dengan cara live testing dan back testing terhadap pasar, dan terbukti bahwa telah mampu menghasilkan keuntungan bagi trader. Metode yang digunakan adalah metode Harmonic Pattern, yang mana didalamnya dapat meng-generate beberapa macam pattern seperti Butterfly, BAMM, Gartley dan sebagainya. Dari pengujian didapat bukti bahwa semua pattern yang dihasilkan memiliki tingkat keberhasilan lebih dari 50%, dimana yang tertinggi adalah pattern Butterfly sebesar 62.33%. Sementara ini untuk pengaturan pada Market Expert Advisor, sistem Risk and Reward yang dikombinasi dengan Trailing Stop akan menghasilkan total profit paling banyak. Namun sistem Martingale akan menghasilkan bentuk grafik yang relatif stabil dan terus menerus meningkatkan modal

    Raman scattering in a two-dimensional electron gas: Boltzmann equation approach

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    The inelastic light scattering in a 2-d electron gas is studied theoretically using the Boltzmann equation techniques. Electron-hole excitations produce the Raman spectrum essentially different from the one predicted for the 3-d case. In the clean limit it has the form of a strong non-symmetric resonance due to the square root singularity at the electron-hole frequency ω=vk\omega = vk while in the opposite dirty limit the usual Lorentzian shape of the cross section is reestablished. The effects of electromagnetic field are considered self-consistently and the contribution from collective plasmon modes is found. It is shown that unlike 3-d metals where plasmon excitations are unobservable (because of very large required transfered frequencies), the two-dimensional electron system gives rise to a low-frequency (ωk1/2\omega \propto k^{1/2}) plasmon peak. A measurement of the width of this peak can provide data on the magnitude of the electron scattering rate.Comment: 4 pages, 3 figures. to appear in Phys. Rev. B 59 (1999

    Inelastic light scattering and the excited states of many-electron quantum dots

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    A consistent calculation of resonant inelastic (Raman) scattering amplitudes for relatively large quantum dots, which takes account of valence-band mixing, discrete character of the spectrum in intermediate and final states, and interference effects, is presented. Raman peaks in charge and spin channels are compared with multipole strengths and with the density of energy levels in final states. A qualitative comparison with the available experimental results is given.Comment: 5 pages, accepted in J. Phys.: Condens. Matte

    First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe

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    We perform a first principles calculation of the anomalous Hall effect in ferromagnetic bcc Fe. Our theory identifies an intrinsic contribution to the anomalous Hall conductivity and relates it to the k-space Berry phase of occupied Bloch states. The theory is able to account for both dc and magneto-optical Hall conductivities with no adjustable parameters.Comment: 4 pages, 6 figures, author list correcte

    Semiquantitative theory of electronic Raman scattering from medium-size quantum dots

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    A consistent semiquantitative theoretical analysis of electronic Raman scattering from many-electron quantum dots under resonance excitation conditions has been performed. The theory is based on random-phase-approximation-like wave functions, with the Coulomb interactions treated exactly, and hole valence-band mixing accounted for within the Kohn-Luttinger Hamiltonian framework. The widths of intermediate and final states in the scattering process, although treated phenomenologically, play a significant role in the calculations, particularly for well above band gap excitation. The calculated polarized and unpolarized Raman spectra reveal a great complexity of features and details when the incident light energy is swept from below, through, and above the quantum dot band gap. Incoming and outgoing resonances dramatically modify the Raman intensities of the single particle, charge density, and spin density excitations. The theoretical results are presented in detail and discussed with regard to experimental observations.Comment: Submitted to Phys. Rev.

    Smart subtitles for vocabulary learning

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    Language learners often use subtitled videos to help them learn. However, standard subtitles are geared more towards comprehension than vocabulary learning, as translations are nonliteral and are provided only for phrases, not vocabulary. This paper presents Smart Subtitles, which are interactive subtitles tailored towards vocabulary learning. Smart Subtitles can be automatically generated from common video sources such as subtitled DVDs. They provide features such as vocabulary definitions on hover, and dialog-based video navigation. In our pilot study with intermediate learners studying Chinese, participants correctly defined over twice as many new words in a post-viewing vocabulary test when they used Smart Subtitles, compared to dual Chinese-English subtitles. Learners spent the same amount of time watching clips with each tool, and enjoyed viewing videos with Smart Subtitles as much as with dual subtitles. Learners understood videos equally well using either tool, as indicated by self-assessments and independent evaluations of their summaries

    First-Principles Dynamical Coherent-Potential Approximation Approach to the Ferromagnetism of Fe, Co, and Ni

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    Magnetic properties of Fe, Co, and Ni at finite temperatures have been investigated on the basis of the first-principles dynamical CPA (Coherent Potential Approximation) combined with the LDA (Local Density Approximation) + UU Hamiltonian in the Tight-Binding Linear Muffintin Orbital (TB-LMTO) representation. The Hamiltonian includes the transverse spin fluctuation terms. Numerical calculations have been performed within the harmonic approximation with 4th-order dynamical corrections. Calculated single-particle densities of states in the ferromagnetic state indicate that the dynamical effects reduce the exchange splitting, suppress the band width of the quasi-particle state, and causes incoherent excitations corresponding the 6 eV satellites. Results of the magnetization vs temperature curves, paramagnetic spin susceptibilities, and the amplitudes of local moments are presented. Calculated Curie temperatures (TCT_{\rm C}) are reported to be 1930K for Fe, 2550K for Co, and 620K for Ni; TCT_{\rm C} for Fe and Co are overestimated by a factor of 1.8, while TCT_{\rm C} in Ni agrees with the experimental result. Effective Bohr magneton numbers calculated from the inverse susceptibilities are 3.0 μB\mu_{\rm B} (Fe), 3.0 μB\mu_{\rm B} (Co), and 1.6 μB\mu_{\rm B} (Ni), being in agreement with the experimental ones. Overestimate of TCT_{\rm C} in Fe and Co is attributed to the neglects of the higher-order dynamical effects as well as the magnetic short range order.Comment: 10 pages, 13 figure

    Severe cholestatic jaundice after a single administration of ajmaline; a case report and review of the literature.

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    BACKGROUND: Ajmaline is a pharmaceutical agent now administered globally for a variety of indications, particularly investigation of suspected Brugada syndrome. There have been previous reports suggesting that repetitive use of this agent may cause severe liver injury, but little evidence exists demonstrating the same effect after only a single administration. CASE PRESENTATION: A 33-year-old man of Libyan origin with no significant past medical history underwent an ajmaline provocation test for investigation of suspected Brugada syndrome. Three weeks later, he presented with painless cholestatic jaundice which peaked in severity at eleven weeks after the test. Blood tests confirmed no evidence of autoimmune or viral liver disease, whilst imaging confirmed the absence of biliary tract obstruction. A liver biopsy demonstrated centrilobular cholestasis and focal rosetting of hepatocytes, consistent with a cholestatic drug reaction. Over the course of the next few months, he began to improve clinically and biochemically, with complete resolution by one year post-exposure. CONCLUSION: Whilst ajmaline-related hepatotoxicity was well-recognised in the era in which the drug was administered as a regular medication, clinicians should be aware that ajmaline may induce severe cholestatic jaundice even after a single dose administration

    Temporary Trans-gastric Stent Deployment Over a 20 French Gastrostomy for Single-Stage Endoscopic Retrograde Cholangiopancreatography After Gastric Bypass

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    Introduction: Treatment of pancreato-biliary disorders after gastric bypass is challenging due to altered anatomy. Several techniques have been proposed to overcome this condition; however, none has emerged as the gold standard treatment. Furthermore, a decision-making algorithm evaluating when and why apply one technique over another is still lacking. Objectives: To describe a novel trans-gastric approach to allow endoscopic retrograde cholangiopancreatography (ERCP) in Roux-en-Y gastric bypass (RYGB) anatomy soon after prior laparoscopic cholecystectomy (LC) and to propose a decision-making algorithm for selection of the most suitable technique according a tailored approach. Setting: Private hospital. Methods: Between January and March 2020, patients with Roux-en-Y gastric bypass anatomy referred to our tertiary center to undergo ERCP after recent laparoscopic cholecystectomy were retrospectively evaluated. A 20 french (Fr) gastrostomy was performed during cholecystectomy. A single-stage ERCP was carried out by means of temporary trans-gastric stent deployment over a 20 Fr gastrostomy. Results: A total of 5 patients (mean age 41; mean body mass index 48.3) were enrolled. ERCP was performed after an average of 2 days from surgery. Technical and clinical success was achieved in 100%. No adverse events occurred. Spontaneous closure of the gastrostomy after its bedside removal was observed in all cases. Conclusions: Our approach allows to perform a single-stage ERCP in RYGB patients, early after LC, with no need of any other re-interventions. Any surgeon facing unexpected biliary disorders, during LC, can easily perform a 20 Fr gastrostomy thus allowing the patient to undergo early ERCP without any delay
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