12,363 research outputs found

    Model Fisik Canal Blocking Bentuk Tabung

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    Canal blocking is closure or insulation of trenches, rivers, or canals permanent or non-permanent that serve to keep the water system and elevation water level stable. With the canal blocking it will affect the flow profile in the channel. The purpose of this research is to investigate the effect of debit coefficient on canal blocking and the influence of bolt and shear force on the stability of canal blocking so as to produce optimal design. The study was conducted in the laboratory by testing the physical model of the blocking canal door. Canal blocking model is made in such a way resembles canal blocking in the field with a scale of 1: 7. Test method is done by variation of the discharge, permeable or unpermeable flow properties, tube arrangement, material weight, and canal blocking of one unit or not a single unit. The results showed that blocking canals have good stability, high efficiency, and economical influenced by several factors, there are type of material, the arrangement and the weight of the material content, the strength of the coefficient of friction (locking / recognition of canal blocking), and the design of permeable or unpermeable

    Lie group analysis of a generalized Krichever-Novikov differential-difference equation

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    The symmetry algebra of the differential--difference equation u˙n=[P(un)un+1un1+Q(un)(un+1+un1)+R(un)]/(un+1un1),\dot u_n = [P(u_n)u_{n+1}u_{n-1} + Q(u_n)(u_{n+1}+u_{n-1})+ R(u_n)]/(u_{n+1}-u_{n-1}), where PP, QQ and RR are arbitrary analytic functions is shown to have the dimension 1 \le \mbox{dim}L \le 5. When PP, QQ and RR are specific second order polynomials in unu_n (depending on 6 constants) this is the integrable discretization of the Krichever--Novikov equation. We find 3 cases when the arbitrary functions are not polynomials and the symmetry algebra satisfies \mbox{dim}L=2. These cases are shown not to be integrable. The symmetry algebras are used to reduce the equations to purely difference ones. The symmetry group is also used to impose periodicity un+N=unu_{n+N}=u_n and thus to reduce the differential--difference equation to a system of NN coupled ordinary three points difference equations

    The Estimation of the Effective Centre of Mass Energy in q-qbar-gamma Events from DELPHI

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    The photon radiation in the initial state lowers the energy available for the e+^+e^- collisions; this effect is particularly important at LEP2 energies (above the mass of the Z boson). Being aligned to the beam direction, such initial state radiation is mostly undetected. This article describes the procedure used by the DELPHI experiment at LEP to estimate the effective centre-of-mass energy in hadronic events collected at energies above the Z peak. Typical resolutions ranging from 2 to 3 GeV on the effective center-of-mass energy are achieved, depending on the event topology.Comment: 12 pages, 6 figure

    Perbedaan Kompetensi Sosial Anak Berdasarkan Tipe Pendidikan Prasekolah

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    Penelitian ini bertujuan untuk mengetahui peran tipe pendidikan prasekolah dalam kompetensi sosial anak. Dua hipotesis diajukan untuk menguji perbedaan kompetensi sosial anak dengan tipe pendidikan prasekolah penuh waktu dan paruh waktu. Subjek penelitian ini adalah 209 orang anak usia lima sampai dengan enam tahun yang mengikuti salah satu tipe pendidikan prasekolah (paruh waktu atau penuh waktu) yang berasal dari enam Taman Kanak-kanak di Yogyakarta (Budi Mulia I Kaliurang, Primagama Kaliurang, ABA Purwodiningratan, Nurul Islam Ringroad Barat, BIAS Kaliurang, dan Budi Mulia Dua Seturan). Data penelitian diperoleh dengan menggunaka skala kompetensi sosial, kuesioner keluarga dan dokumentasi sekolah. Skala kompetensi sosial dinilai oleh guru kelas dengan menggunakan teknik interrater. Jumlah item pada skala kompetensi sosial adalah 30 item. Setelah uji coba terdapat 4 item yang gugur. Daya beda item berkisar dari 0,303-0,581 dengan angka reliabilitas 0,890. Sedangkan nilai reliabilitas antar rater berkisar antara 0,867-0,998. Hasil ANCOVA, diperoleh kesimpulan hasil penelitian bahwa: (1) ada perbedaan kompetensi sosial anak dengan tipe pendidikan prasekolah paruh waktu dan penuh waktu. Kompetensi sosial anak dengan tipe pendidikan prasekolah penuh waktu lebih tinggi daripada kompetensi sosial anak dengan tipe pendidikan prasekolah paruh waktu (F = 21,612; p = 0,000). (2) tidak ada korelasi antara kompetensi sosial anak yang berusia lima tahun sampai dengan enam tahun (F = 1,781; p = 0,184)

    Performance of a Tungsten-Cerium Fluoride Sampling Calorimeter in High-Energy Electron Beam Tests

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    A prototype for a sampling calorimeter made out of cerium fluoride crystals interleaved with tungsten plates, and read out by wavelength-shifting fibres, has been exposed to beams of electrons with energies between 20 and 150 GeV, produced by the CERN Super Proton Synchrotron accelerator complex. The performance of the prototype is presented and compared to that of a Geant4 simulation of the apparatus. Particular emphasis is given to the response uniformity across the channel front face, and to the prototype's energy resolution.Comment: 6 pages, 6 figures, Submitted to NIM

    Algorithms for Stable Matching and Clustering in a Grid

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    We study a discrete version of a geometric stable marriage problem originally proposed in a continuous setting by Hoffman, Holroyd, and Peres, in which points in the plane are stably matched to cluster centers, as prioritized by their distances, so that each cluster center is apportioned a set of points of equal area. We show that, for a discretization of the problem to an n×nn\times n grid of pixels with kk centers, the problem can be solved in time O(n2log5n)O(n^2 \log^5 n), and we experiment with two slower but more practical algorithms and a hybrid method that switches from one of these algorithms to the other to gain greater efficiency than either algorithm alone. We also show how to combine geometric stable matchings with a kk-means clustering algorithm, so as to provide a geometric political-districting algorithm that views distance in economic terms, and we experiment with weighted versions of stable kk-means in order to improve the connectivity of the resulting clusters.Comment: 23 pages, 12 figures. To appear (without the appendices) at the 18th International Workshop on Combinatorial Image Analysis, June 19-21, 2017, Plovdiv, Bulgari

    Archaeometric approach for the study of mortars from the underwater archaeological site of Baia (Naples) Italy: Preliminary results

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    This work was aimed to evaluate the features of mortar samples taken from the underwater archaeological area of Baia (Naples, Italy), an important site, where the remains of the ancient Roman city of Baiae and Portus Iulius are submerged after bradyseism events, started from 4th century AD. Several architectural structures are still preserved into the submerged environment, such as: luxurious maritime villas, imperial buildings, private houses, thermae, tabernae and warehouses. In particular, some samples were collected from the masonry walls belonging to a building of the underwater area called Villa a Protiro. A first archaeometric approach has been applied to analyse twelve archaeological mortars samples in order to define: textural features, chemical composition and raw materials used for their production. For this purpose different analytical methods were used, such as, polarizing optical microscope (POM) and scanning electron microscopy (SEM-EDS).This work was financially supported by national national research project “COMAS” (Planned COnservation, “in situ”, of underwater archaeological artifacts), funded by the Italian Ministry of Education, Universities and Research (MIUR).Peer reviewe

    Constraints on anomalous Higgs boson couplings using production and decay information in the four-lepton final state

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    A search is performed for anomalous interactions of the recently discovered Higgs boson using matrix element techniques with the information from its decay to four leptons and from associated Higgs boson production with two quark jets in either vector boson fusion or associated production with a vector boson. The data were recorded by the CMS experiment at the LHC at a center-of-mass energy of and correspond to an integrated luminosity of . They are combined with the data collected at center-of-mass energies of 7 and , corresponding to integrated luminosities of 5.1 and , respectively. All observations are consistent with the expectations for the standard model Higgs boson

    Localized induction equation and pseudospherical surfaces

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    We describe a close connection between the localized induction equation hierarchy of integrable evolution equations on space curves, and surfaces of constant negative Gauss curvature.Comment: 21 pages, AMSTeX file. To appear in Journal of Physics A: Mathematical and Genera

    Gradient catastrophe and flutter in vortex filament dynamics

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    Gradient catastrophe and flutter instability in the motion of vortex filament within the localized induction approximation are analyzed. It is shown that the origin if this phenomenon is in the gradient catastrophe for the dispersionless Da Rios system which describes motion of filament with slow varying curvature and torsion. Geometrically this catastrophe manifests as a rapid oscillation of a filament curve in a point that resembles the flutter of airfoils. Analytically it is the elliptic umbilic singularity in the terminology of the catastrophe theory. It is demonstrated that its double scaling regularization is governed by the Painlev\'e-I equation.Comment: 11 pages, 3 figures, typos corrected, references adde
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