Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Design Diversity for Improving Efficiency and Reducing Risk in Oil and
  Gas Well Stimulation under Uncertain Reservoir Conditions   Hydraulic fracturing stimulates fracture swarm in reservoir formation though
pressurized injection fluid. However restricted by the availability of
formation data, the variability embraced by reservoir keeps uncertain, driving
unstable gas recovery along with low resource efficiency, being responsible for
resource scarcity, contaminated water, and injection-induced earthquake.
Resource efficiency is qualified though new determined energy efficiency, a
scale of recovery and associated environmental footprint. To maximize energy
efficiency while minimize its' variation, we issue picked designs at reservoir
conditions dependent optimal probabilities, assembling high efficiency
portfolios and low risk portfolios for portfolio combination, which balance the
variation and efficiency at optimal by adjusting the proportion of each
portfolio. Relative to regular design for one well, the optimal portfolio
combination applied in multiple wells receive remarkable variation reduction
meanwhile substantial energy efficiency increase, in response to the call of
more recovery per unit investment and less environment cost per unit nature gas
extracted.

32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int