the theoretical basis for data communication
Tài liệu Lecture 14: The Theoretical Basis for Data Communication: pptx
Ngày tải lên :
10/12/2013, 08:15
... 2000 Lecture 14 Communication Basics Part-2
The Theoretical Basis for Data Communication:
Frequency-domain concept:
A sine wave with a frequency of 1 kHz will look like this in the frequency ...
So, for a 10 dBm signal (10 mW) the noise level has to be less than -20 dBm (10 microW).
Shanon Theorem:
Mathematical guidelines have been established to determine the maximum theoretical ... another.
The formula for calculating decibel is :
dB = 10 log P
o
/P
i
= 10 log 1000mW/10mW
= 10 log 100
= 10 x 2
=20
dB tells us the ratio of two power levels, that is it expresses the...
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Báo cáo khoa học: The structural basis for catalytic function of GMD and RMD, two closely related enzymes from the GDP-D-rhamnose biosynthesis pathway pdf
Ngày tải lên :
16/03/2014, 01:20
... was performed for 1 h, the enzyme was
removed by filtration, and then enzyme and cofactor for
the second reaction were added. To determine the optimal
pH for enzyme-catalyzed reactions, the extent ... positions of the corresponding side chain, Arg220,
the NADPH cofactor and the substrate analog hexose
in the MUR1 structure (Fig. 11). Some of the distances
between these groups are rather long for classic ... form the catalytic triad. No clear electron density is seen for the nicotinamide ring,
and even the nicotinamide ribose shows some indications of disorder; in fact, the average B-factor for the...
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Tài liệu Chapter 6 The Data Communications Interface pdf
Ngày tải lên :
16/02/2014, 08:20
... transition 1 to 0
❚
Then samples next seven intervals (char length)
❚
Then looks for next 1 to 0 for next char
❚
Simple
❚
Cheap
❚
Overhead of 2 or 3 bits per char (~20%)
❚
Good for data with large ... data
❙
Manchester encoding
❙
Carrier frequency (analog)
William Stallings
Data and Computer
Communications
Chapter 6
The Data Communications
Interface
Synchronous - Block Level
❚
Need to indicate ... carry both data and control
ISDN Electrical Specification
❚
Balanced transmission
❙
Carried on two lines, e.g. twisted pair
❙
Signals as currents down one conductor and up the other
❙
Differential...
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Tài liệu Báo cáo khoa học: Kinetic basis for linking the first two enzymes of chlorophyll biosynthesis doc
Ngày tải lên :
20/02/2014, 02:21
... methyltransferase
steps. The K
D
for the H ⁄ ID interaction was
taken from Jensen et al. 1998 [24], and the
K
D
for the association with ChlM is from
Fig. 1. The possible effects of varying the
concentration of the ... greatly influence the cata-
lytic rate of CHLM, the eukaryotic MgP methyl-
transferase. This has important implications for the
coupling between these steps and for the availability
of MgP for signalling. ... 4537
Kinetic basis for linking the first two enzymes of
chlorophyll biosynthesis
Mark Shepherd, Samantha McLean and C. Neil Hunter
Robert Hill Institute for Photosynthesis and Krebs Institute for Biomolecular...
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Đề tài " A five element basis for the uncountable linear orders " doc
Ngày tải lên :
06/03/2014, 08:21
... element basis. In fact such a basis follows from the Proper
Forcing Axiom, a strong form of the Baire Category Theorem. The elements
are X, ω
1
, ω
∗
1
, C, C
∗
where X is any suborder of the reals ... versed in set
theory and the major developments in the field in the 70s and 80s. The reader
is assumed to have proficiency in the areas of Aronszajn tree combinatorics,
forcing axioms, the combinatorics ... ∆
X
ξ
(0),X
η
(0)
are in K for all j<n.
The next lemma draws the connection between ∂H(K) and the forcing
∂(K). We will then spend the remainder of the paper analyzing ∂(K).
Lemma 5.22...
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Báo cáo khoa học: Investigations into the ability of an oblique a-helical template to provide the basis for design of an antimicrobial anionic amphiphilic peptide pot
Ngày tải lên :
07/03/2014, 12:20
... membranes, but, in the presence of the
peptide, they are positive. These results confirm that
E. coli membranes are thermodynamically less stable
in the presence of AP1, further supporting the sugges-
tion ... observed for E. coli model
membranes, indicating that, although the lipids form-
ing these monolayers are miscible, repulsive interac-
tions are established in the presence of the peptide,
thereby ... pressure (p) for lipid
mixtures that correspond to membranes of E. coli. Values for these parameters were computed either in the presence or absence of AP1
using data from compression isotherms (Fig....
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Báo cáo khoa học: Structural basis for the erythro-stereospecificity of the L-arginine oxygenase VioC in viomycin biosynthesis docx
Ngày tải lên :
16/03/2014, 02:20
... conformational control of the bound sub-
strate, which enforces a gauche(–) conformer for v
1
instead of the trans
conformers observed for the asparagine oxygenase AsnO and other mem-
bers of the ... trans to modify
the assembled peptide or to synthesize the building
blocks for the nonribosomal peptide synthesis [9,10]. In
the case of viomycin, the annotation of the biosynthesis
gene cluster ... mimic, the tartrate
is similarly bound as found before for aKG and succi-
nate in other CSL oxygenases [20,21]. The coordina-
tion of the 1-carboxylate of aKG is known to be
either trans to the...
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Báo cáo khoa học: "Theoretical Evaluation of Estimation Methods for Data-Oriented Parsing" pot
Ngày tải lên :
17/03/2014, 22:20
... reliably
recover the true weights.
The relevant test is whether for all possible
STSGs and in the limit of infinite data, the ex-
pected relative frequencies of trees given the es-
timated grammar, equal the ... com-
binations of the frequencies f
1
. . . f
4
. Observa-
tions of these frequencies therefore do not add
any extra information, and the problem of fi nd-
ing the weights of the target grammar ... TV, Amsterdam, the Netherlands.
jzuidema@science.uva.nl
Abstract
We analyze estimation methods for Data-
Oriented Parsing, as well as the theoret-
ical criteria used to evaluate them. We
show...
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Báo cáo Y học: Structural basis for the inhibitory efficacy of efavirenz (DMP-266), MSC194 and PNU142721 towards the HIV-1 RT K103N mutant doc
Ngày tải lên :
18/03/2014, 01:20
... reduced by
the s tacking of O d1 in between the plane of the thiourea
moiety and the Ca of G190.
Hence, the undefined orientation of the N103 amide Od1
and Nd2 atoms may r eflect the repulsive forces ... with the K103N
mutant revealed that the overall position of the inhibitor as
well as the r esidues lining the NNIBP corresponds to the
wild-type–Efavirenz complex (Fig. 3). C omparison between
the ... (Table 3).
The effects of the K103N mutation on the hydrophobic
interactions reveal individual differences among the t hree
compounds. Though t he electron density for the a mide part
of the residue...
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Báo cáo khoa học: Structural basis for the recognition of complex-type biantennary oligosaccharides by Pterocarpus angolensis lectin ppt
Ngày tải lên :
23/03/2014, 11:20
... NA2F. These results together with thermodynamic
binding data indicate that the complete oligosaccharide binding site of the
lectin consists of five subsites allowing the specific recognition of the ... car-
bohydrate. The electron density for four
water molecules that occupy the binding
site is shown, together with the hydrogen
bond network these waters make with the
protein. Superimposed in black are the
equivalent ... conclude that the
reason for the difference in energetics of the )1 subsite
between PAL and con A must be due to details in the
interaction between the protein and the carbohydrate
and not to the carbohydrate...
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Published quarterly by the Research Collaboratory for Structural Bioinformatics Protein Data Bank ppt
Ngày tải lên :
29/03/2014, 09:20
... award points for the
accuracy of the model and for the
addition of materials that illustrated
the function of the protein.
The team from South
Brunswick marked the beta
sheets in their model after
viewing ... generate
reports, the different options for exploring individual structures,
and many of the resources and tools available at the RCSB PDB
for research and education. The full tutorial runs for about ... options, the Molecule of the
Month can be replaced with forms to download files and search by sequence.
Other widgets that can be displayed on the home page include the RCSB PDB
Comparison Tool for...
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Báo cáo khoa học: Structural basis for the interaction between dynein light chain 1 and the glutamate channel homolog GRINL1A docx
Ngày tải lên :
29/03/2014, 09:20
... area.
Figure 4A shows the 20 lowest-energy conformers
from the selected cluster modelled using the Haddock
docking calculations. The rmsd values for the 20
lowest-energy conformers of the best cluster ... 0.11 A
˚
for the backbone and 1.11 ± 0.09 A
˚
for the heavy atoms. The mean total energy of the
ensemble is )8146 kcalÆmol
)1
, being )314 kcalÆmol
)1
the intermolecular contribution. The corresponding
values ... present in the
GRINL1A target, the interaction still occurs in
the canonical mode (Fig. 4B). The peptide lies along the
grooves at each side of the DYNLL1 dimer interface,
extending the central...
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Báo cáo khoa học: "Big Data versus the Crowd: Looking for Relationships in All the Right Places" docx
Ngày tải lên :
30/03/2014, 17:20
... Freebase and the corpus into two halves.
One database-corpus pair is used for training and the
other pair for testing. We evaluate the precision over
the 10
3
highest-probability predictions on the test
set. ... re-
call. On the other hand, the quality improvement
rate is roughly log-linear against the corpus size.
Recall that each data point in Figure 2 is the aver-
age from 30 trials. To measure the statistical ... the test
set. In Figure 5, we vary the size of the corpus in the
train pair and the number of human labels; the pre-
cision reaches a dramatic peak when we the corpus
size is above 10
5
and uses...
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Báo cáo khoa học: Structural basis for the changed substrate specificity of Drosophila melanogaster deoxyribonucleoside kinase mutant N64D docx
Ngày tải lên :
30/03/2014, 20:20
... with the substrate dT, in red,
and with AZT modeled in the substrate binding site, in blue. The
interactions with the substrate are the same in the wildtype and
the N64D mutant except for the ... and
analyzing the data by the Biosoft (Cambridge, UK) pro-
gram enzfitter for Windows.
Crystallization
The N64D mutant used for crystallization was truncated
for the 20 C-terminal amino acids. The C-terminal ... is there-
fore a particularly attractive candidate for the medical
gene therapy applications mentioned above, as well as
for industrial synthesis of d(d)NTPs and their analogs
[6,15]. To further...
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Báo cáo khoa học: "A Logical Basis for the D Combinator and Normal Form in CCG" pptx
Ngày tải lên :
31/03/2014, 00:20
... Wallace) ate)?
Finally, the unary combinator basis for CCG pro-
vides an interesting additional specification for gen-
erating CCG rules. Like the CTL basis, the unary
combinator basis can produce a ... two theorems about the
set of semantically equivalent parses that a CCG
parser will generate for a given string (see (Eisner,
1996) for proofs and discussion of the theorems):
(31) Theorem 1 : For ... Nos
cl.1p
hizo
made.3s
leer
read
El
the
Señor
Lord
de
of
los
the
Anillos.
Rings
“He made us read The Lord of the Rings.”
The aspect of the construction that is relevant here
is that the causative verb hacer...
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