244 research outputs found
Pengaruh Fermentasi Kombinasi Jamur Pleurotus Ostreatus Dengan Trichoderma Viridae Terhadap Kandungan Nutrien Dan Aktivitas Enzim Selulase Bungkil Kopra
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
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 â Piksel. Hasil proses deteksi dengan perhitungan dimensi berupa merekomendasikan bahwa obyek berjenis Pisau atau Bukan Pisau
The AdS/QCD Correspondence: Still Undelivered
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
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
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
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
We holographically study the effect of back reaction on the hydrodynamical
properties of strongly coupled super Yang-Mills (SYM) thermal
plasma. The back reaction we consider arises from the presence of static heavy
quarks uniformly distributed over 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
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
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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