A
bstract
The anomalies in the measurements of observables involving
b
→
sμμ
decays, namely
R
K
,
R
K
*
,
P
5
′
, and
B
s
ϕ
, may be addressed by adding lepton-universality-violating new physics ...contributions to the effective operators
O
9
,
O
10
,
O
9
′
,
O
10
′
. We analyze all the scenarios where the new physics contributes to a pair of these operators at a time. We perform a global fit to all relevant data in the
b
→
s
sector to estimate the corresponding new Wilson coefficients,
O
9
N
P
,
O
10
N
P
,
O
9
′
,
O
10
′
. In the light of the new data on
R
K
, and
R
K
*
, presented in Moriond 2019, we find that the scenarios with new physics contributions to the
O
9
N
P
O
9
′
or
O
9
N
P
O
10
′
pair remain the most favored ones. On the other hand, though the competing scenario
O
9
N
P
O
10
N
P
remains attractive, its advantage above the SM reduces significantly due to the tension that emerges between the
R
K
and
R
K
*
measurements with the new data. The movement of the
R
K
measurement towards unity would also result in the re-emergence of the one-parameter scenario
C
9
NP
= −
C
9
′
.
This work proposes an energy-efficient resource provisioning and allocation framework to meet dynamic demands of the future applications. The frequent variations in a cloud user’s resource demand ...leads to the problem of an excess power consumption, resource wastage, performance and Quality-of-Service (QoS) degradation. The proposed framework addresses these challenges by matching the application’s predicted resource requirement with resource capacity of VMs precisely and thereby consolidating entire load on the minimum number of energy-efficient physical machines (PMs). The three consecutive contributions of the proposed work are: (1) Online Multi-Resource Feed-forward Neural Network (OM-FNN) to forecast the multiple resource demands concurrently for the future applications, (2) autoscaling of VMs based on the clustering of the predicted resource requirements, (3) allocation of the scaled VMs on the energy-efficient PMs. The integrated approach successively optimizes resource utilization, saves energy and automatically adapts to the changes in future application resource demand. The proposed framework is evaluated by using real workload traces of the benchmark Google Cluster Dataset and compared against different scenarios including energy-efficient VM placement (VMP) with resource prediction only, VMP without resource prediction and autoscaling, and optimal VMP with autoscaling based on actual resource utilization. The observed results demonstrate that the proposed integrated approach achieves near-optimal performance against optimal VMP and outperforms rest of the VMPs in terms of power saving and resource utilization up to 88.5% and 21.12% respectively. In addition, OM-FNN predictor shows better accuracy, lesser time and space complexity over a traditional single-input and single-output feed-forward neural network (SISO-FNN) predictor.
In spite of various gains, cloud computing has got few challenges and issues including dynamic resource scaling and power consumption. Such affairs cause a cloud system to be fragile and expensive. ...In this paper we address both issues in cloud datacenter through workload prediction. The workload prediction model is developed using long short term memory (LSTM) networks. The proposed model is tested on three benchmark datasets of web server logs. The empirical results show that the proposed method achieved high accuracy in predictions by reducing the mean squared error up to 3.17 x 10-3.
The ability of the TiO2–based photocatalysis process to mineralize organic pollutants has attracted attention worldwide for the degradation of recalcitrant pharmaceuticals and personal care products ...(PPCPs). Nevertheless, (1) the limited exploitation of the solar spectrum, i.e., activation under UV light (only 2–3% of solar spectrum), and (2) the high recombination rate of photo-generated charge carriers, i.e., electrons and holes, have limited its application which can, however, be improved by developing a TiO2–based heterojunction. The objective of this critical review paper is to discuss the recent developments (2009–2019) in visible–light–driven (VLD) TiO2–based heterojunctions for PPCP degradation and their degradation mechanisms. Compared to the conventional heterojunctions, Schottky and Z–scheme heterojunctions, which are non-conventional heterojunctions, are found to be more effective for PPCP degradation due to their more efficient separation of charge carriers and the occurrence of redox reactions at a relatively higher redox potential. Furthermore, the enhancement strategies for the development of a VLD TiO2–based heterojunction are also explored which can be achieved by selecting the (1) highly photocatalytically active {001} facet of anatase TiO2, (2) synthesis methods governing the structural changes at the junction interface, and (3) heterojunction components which can efficiently generate the powerful •OH radicals. The challenges in practical applications are also discussed which include factors, viz., cost reduction, recycling, stability, byproducts analysis, evaluation of the environmental effectiveness, and reactor design and scale-up of the VLD TiO2–based heterojunctions. Accordingly, the prospects of VLD TiO2–based heterojunctions for PPCP degradation in real environmental applications are discussed.
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•Visible–light–driven TiO2–based heterojunctions for PPCP degradation are reviewed.•Mechanisms of conventional and non-conventional heterojunctions are discussed.•Efficiency enhancement strategies for TiO2–based heterojunctions are investigated.•Challenges in practical application of TiO2–based heterojunctions are discussed.•Future prospects in real environmental applications are summarized.
New physics solutions for RD and RD Alok, Ashutosh Kumar; Kumar, Dinesh; Kumar, Jacky ...
The journal of high energy physics,
09/2018, Letnik:
2018, Številka:
9
Journal Article
Recenzirano
Odprti dostop
A
bstract
Recent measurements of
R
D
∗
have reduced tension with the Standard Model prediction. Taking all the present data into account, we obtain the values of the Wilson coefficients of each new ...physics four-fermion operator of a given Lorentz structure. We find that the combined data rule out most of the solutions based on scalar/pseudoscalar operators. By studying the inter-relations between different solutions, we find that there are only four allowed solutions, which are based on operators with (
V
−
A
), linear combination of (
V
−
A
) and (
V
+
A
), tensor and linear combination of scalar/pseudoscalar and tensor structure. We demonstrate that the need for new physics is driven by those measurement of
R
D
and
R
D
∗
where the τ lepton is not studied. Further, we show that new physics only in
b
→
c
μ
ν
¯
is not compatible with the full set of observables in the decays
B
→
D
l
ν
¯
and
B
→
D
∗
l
ν
¯
.
Earlier this year, the Belle collaboration presented their new measurements of RD and RD⁎ using a new method. These measurements are consistent with the Standard Model predictions, whereas the global ...averages of the earlier measurements had a 4.1σ discrepancy. With the inclusion of the new data in the global averages, the discrepancy comes down to 3.1σ. In this work, we study the new physics solutions to the RD-RD⁎ anomaly allowed by the reduction in the discrepancy. Among the four fermion operators, which arise through a single particle exchange, only the (V−A) operator solution survives. We found three additional solutions with two dis-similar operators. The branching ratio of Bc→τν¯ is powerful discriminant between these four allowed solutions.
The measurements of the ratios
R
K
(
∗
)
along with
R
D
(
∗
)
hint towards lepton flavor non universality which is in disagreement with the standard model. In this work, we reanalyze the four new ...physics models, which are widely studied in the literature as a candidates for the simultaneous explanations of these measurements. These are, standard model like vector boson (VB),
S
U
(
2
)
L
-singlet vector leptoquark (
U
1
),
S
U
(
2
)
L
-triplet scalar leptoquark (
S
3
) and
S
U
(
2
)
L
triplet vector leptoquark (
U
3
) models. We assume a coupling only to the third generation in the weak basis, so that the
b
→
s
μ
+
μ
-
transition is generated only via mixing effects. Preforming a global fit to all relevant data, we show that the vector boson model violates the current upper bound on
Br
(
τ
→
3
μ
)
and hence is
inconsistent
with the present data. Further, we show that within this framework, the
U
1
leptoquark model
cannot
simultaneously accommodate
R
K
(
∗
)
and
R
D
(
∗
)
measurements. We emphasize that this conclusion is independent of the additional constraints coming from renormaliztion group running effects and high-
p
T
searches. In addition, we show that the
S
3
and
U
3
models are highly disfavored by the constraints coming from
b
→
s
ν
ν
¯
data. Finally, we find a that hypothesis of two LQ particles is also challenged by
b
→
s
ν
¯
ν
data.
Composite materials can be promising to decouple electron and phonon transport for improved thermoelectric properties. Herein, the synergistic effect of the particle size of the dispersed phase and ...the interface thermal resistance (Rint) between the phases on the phonon thermal conductivity (κph) of the (1-x)La0.95Sr0.05Co0.95Mn0.05O3/(x)WC thermoelectric composite is demonstrated. The embedded WC, owing to its high electrical conductivity (σ), does improve σ of the composite. A high acoustic impedance mismatch between the phases results in a large Rint and lowers κph. Change in κph is further explained using theoretical analysis of Bruggeman asymmetrical model. The correlation between Rint and Kapitza radius is discussed to analyze the reduced κph. Synergistic effect of improved σ and lowered κph result in improved thermoelectric figure of merit (zT) of 0.20 at 463 K for (1-x)La0.95Sr0.05Co0.95Mn0.05O3/(x)WC composite. This study shows promise to design thermoelectric composites with the desired κph considering the elastic properties between the phases.
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Nanoscience and nanotechnology have seen an exponential growth over the past decade largely due to the unique properties of engineered nanoparticles (ENPs), advances in ENP synthesis, and imaging or ...analysis tools. The unique properties such as high surface area to volume ratio, abundant reactive sites on the surface, large fraction of atoms located on the exterior face have made these novel materials the most sought after for consumer and industrial applications. This significant increase in the ENP containing consumer products has also enhanced the chances of human and environmental exposure. Humans get exposed to ENPs at various steps of its synthesis (laboratory), manufacture (industry), use (consumer products, devices, medicines, etc.) and through the environment (contaminated water, aerosolized particles, and disposal). Such exposures to ENPs are known to induce genotoxicity, cytotoxicity, and carcinogenicity in biological system. This is attributed to several factors, such as direct interaction of ENPs with the genetic material, indirect damage due to reactive oxygen species generation, release of toxic ions from soluble ENPs, interaction with cytoplasmic/nuclear proteins, binding with mitotic spindle or its components, increased oxidative stress, disturbance of cell cycle checkpoint functions, inhibition of antioxidant defense, and many others. The present review describes an overview of in vitro and in vivo genotoxicity studies with ENPs, advantages and potential problems associated with the methods used in genotoxicity assessment, and the need for appropriate method and approach for risk assessment of ENPs.
This paper explores the folklore of indentured Indians and endeavors to understand the elements of Indian folk culture in the sugar colonies in the age of the empires. While examining the content and ...context of the folklore, it finds that the indentured folktales were very much influenced by the Indian socio-cultural life, however, these folktales got transformed and modified due to the contact with host countries’ languages, places and space. On the other hand, the content of the indentured folksongs not only depicted the culture and pain of separation from homeland and familial ties, but also became an instrument to resist against the plantation hardship.
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