244 research outputs found

    Pengaruh Fermentasi Kombinasi Jamur Pleurotus Ostreatus Dengan Trichoderma Viridae Terhadap Kandungan Nutrien Dan Aktivitas Enzim Selulase Bungkil Kopra

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    Copra meal is by-product of oil extraction that is produced in large quantity and relatively cheap in Indonesia. However, its high cellulose becomes obstacle for poultry diet. Two studies was conducted to optimize the utilization of copra meal by producing crude enzyme that matched with copra meal using solid state fermentation method with various doses and incubation time that mixed with Pleurotus ostreatus (PO) and Trichoderma viridae (TV). In the first study, copra meal was fermented with 4 levels of inoculum (L0 = no inoculum; L1 = 17.7 CFU/g of TV and 175.00 CFU/g of PO per kg of copra meal; L2 = 35.4 CFU/g of TV and 218.75 CFU/g of PO per kg of copra meal; L3 = 53.1 CFU/g of TV and 262.50 CFU/g of PO per kg of copra meal and 4 incubation time (W1= 4 days; W2 = 6 days; W3 = 8 days; and W4 = 10 days). Parameters measured were crude protein, crude lipid, crude fibre and gross energy. A completely randomized factorial design was used in the study. In the second study, crude enzyme was produced from the best results found in the first study. A method of Jacob and Prema (2006) was used to produce enzyme. Meanwhile, activity of cellulase was measured based on the method of Omojosola (2008). The results showed that factor of inoculum level was found significantly increased protein content and gross energy but decreased crude lipid and crude fibre of the mixed fungi-fermented copra meal. Incubation time did not affect protein content but significanly affected crude lipid, crude fibre and gross energy. Interactions between inoculum level and incubation time was found in crude lipid, crude fibre and gross energy contents of mixed fungi-fermented copra meal. Activity of cellulase was 0.71 g glucose/l

    Deteksi Objek Senjata Tajam Pada Citra X-ray Dengan Metode Pengukuran Dimensi Citra

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    Proses diawali dengan mengubah citra RGB ke YCbYr kemudian dipilih kanal Cb sebagai deteksi warna dan dilanjutkan dengan 3 proses lainnya terdiri dari : binerisasi dengan tujuan mengubah citra menjadi hitam putih, filterisasi berguna untuk menghilangkan noise, segmentasi untuk mengambangkan obyek dan hitung dimensi obyek terdiri dari nilai RV dan ∑ Piksel. Hasil proses deteksi dengan perhitungan dimensi berupa merekomendasikan bahwa obyek berjenis Pisau atau Bukan Pisau

    The AdS/QCD Correspondence: Still Undelivered

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    We consider the particle spectrum and event shapes in large N gauge theories in different regimes of the short-distance 't Hooft coupling, lambda. The mesons in the small lambda limit should have a Regge spectrum in order to agree with perturbation theory, while generically the large lambda theories with gravity duals produce spectra reminiscent of KK modes. We argue that these KK-like states are qualitatively different from QCD modes: they are deeply bound states which are sensitive to short distance interactions rather than the flux tube-like states expected in asymptotically free, confining gauge theories. In addition, we also find that the characteristic event shapes for the large lambda theories with gravity duals are close to spherical, very different from QCD-like (small lambda, small N) and Nambu-Goto-like (small lambda, large N) theories which have jets. This observation is in agreement with the conjecture of Strassler on event shapes in large 't Hooft coupling theories, which was recently proved by Hofman and Maldacena for the conformal case. This conclusion does not change even when considering soft-wall backgrounds in the gravity dual. The picture that emerges is the following: theories with small and large lambda are qualitatively different, while theories with small and large N are qualitatively similar. Thus it seems that it is the relative smallness of the 't Hooft coupling in QCD that prevents a reliable AdS/QCD correspondence from emerging, and that reproducing characteristic QCD-like behavior will require genuine stringy dynamics to be incorporated into any putative dual theory.Comment: 32 pages, 15 figures; references added, minor changes, history clarifie

    Description of LHC data in a soft interaction model

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    We show in this paper that we have found a set of parameters in our model for the soft interactions at high energy, that successfully describes all high energy experimental data, including the LHC data. This model is based on a single Pomeron with large intercept \Delta_\pom = 0.23 and slope \alpha'_\pom = 0, that describes both long and short distance processes. It also provides a natural matching with perturbative QCD. All features of our model are similar to the expectations of N=4 SYM, which at present is the only theory that is able to treat srong interactions on a theoretical basis.Comment: 11 pages with 7 figures in eps format

    Colliding AdS gravitational shock waves in various dimensions and holography

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    The formation of marginally trapped surfaces in the off-center collision of two shock waves on AdS_D (with D=4,5,6,7 and 8) is studied numerically. We focus on the case when the two waves collide with nonvanishing impact parameter while the sources are located at the same value of the holographic coordinate. In all cases a critical value of the impact parameter is found above which no trapped surface is formed. The numerical results show the existence of a simple scaling relation between the critical impact parameter and the energy of the colliding waves. Using the isometries of AdS_D we relate the solutions obtained to the ones describing the collision of two waves with a purely holographic impact parameter. This provides a gravitational dual for the head-on collision of two lumps of energy of unequal size.Comment: 25 pages, 11 figures. v2: minor changes, typos corrected. To appear in JHE

    Drag and jet quenching of heavy quarks in a strongly coupled N=2* plasma

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    The drag of a heavy quark and the jet quenching parameter are studied in the strongly coupled N=2* plasma using the AdS/CFT correspondence. Both increase in units of the spatial string tension as the theory departs from conformal invariance. The description of heavy quark dynamics using a Langevin equation is also considered. It is found that the difference between the velocity dependent factors of the transverse and longitudinal momentum broadening of the quark admit an interpretation in terms of relativistic effects, so the distribution is spherical in the quark rest frame. When conformal invariance is broken there is a broadening of the longitudinal momentum distribution. This effect may be useful in understanding the jet distribution observed in experiments.Comment: 30 pages, 5 figures, references added, minor corrections. To be published in JHE

    Back reaction effects on the dynamics of heavy probes in heavy quark cloud

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    We holographically study the effect of back reaction on the hydrodynamical properties of N=4\mathcal{N} = 4 strongly coupled super Yang-Mills (SYM) thermal plasma. The back reaction we consider arises from the presence of static heavy quarks uniformly distributed over N=4\mathcal{N} = 4 SYM plasma. In order to study the hydrodynamical properties, we use heavy quark as well as heavy quark-antiquark bound state as probes and compute the jet quenching parameter, screening length and binding energy. We also consider the rotational dynamics of heavy probe quark in the back-reacted plasma and analyse associated energy loss. We observe that the presence of back reaction enhances the energy-loss in the thermal plasma. Finally, we show that there is no effect of angular drag on the rotational motion of quark-antiquark bound state probing the back reacted thermal plasma.Comment: 29 pages, 21 figure

    Survival probability of large rapidity gaps in QCD and N=4 SYM motivated model

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    In this paper we present a self consistent theoretical approach for the calculation of the Survival Probability for central dijet production . These calculations are performed in a model of high energy soft interactions based on two ingredients:(i) the results of N=4 SYM, which at the moment is the only theory that is able to deal with a large coupling constant; and (ii) the required matching with high energy QCD. Assuming, in accordance with these prerequisites, that soft Pomeron intercept is rather large and the slope of the Pomeron trajectory is equal to zero, we derive analytical formulae that sum both enhanced and semi-enhanced diagrams for elastic and diffractive amplitudes. Using parameters obtained from a fit to the available experimental data, we calculate the Survival Probability for central dijet production at energies accessible at the LHC. The results presented here which include the contribution of semi-enhanced and net diagrams, are considerably larger than our previous estimates.Comment: 11 pages, 10 pictures in .eps file

    Early-Time Energy Loss in a Strongly-Coupled SYM Plasma

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    We carry out an analytic study of the early-time motion of a quark in a strongly-coupled maximally-supersymmetric Yang-Mills plasma, using the AdS/CFT correspondence. Our approach extracts the first thermal effects as a small perturbation of the known quark dynamics in vacuum, using a double expansion that is valid for early times and for (moderately) ultrarelativistic quark velocities. The quark is found to lose energy at a rate that differs significantly from the previously derived stationary/late-time result: it scales like T^4 instead of T^2, and is associated with a friction coefficient that is not independent of the quark momentum. Under conditions representative of the quark-gluon plasma as obtained at RHIC, the early energy loss rate is a few times smaller than its late-time counterpart. Our analysis additionally leads to thermally-corrected expressions for the intrinsic energy and momentum of the quark, in which the previously discovered limiting velocity of the quark is found to appear naturally.Comment: 39 pages, no figures. v2: Minor corrections and clarifications. References added. Version to be published in JHE
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