Class-based Rough Approximation with Dominance Principle

Dominance-based Rough Set Approach (DRSA), as the extension of Pawlak's Rough Set theory, is effective and fundamentally important in Multiple Criteria Decision Analysis (MCDA). In previous DRSA models, the definitions of the upper and lower approximations are preserving the class unions rather than the singleton class. In this paper, we propose a new Class-based Rough Approximation with respect to a series of previous DRSA models, including Classical DRSA model, VC-DRSA model and VP-DRSA model. In addition, the new class-based reducts are investigated.Comment: Submitted to IEEE-GrC201

The role of criticality on the horizontal and vertical scales of extratropical eddies in a dry GCM

This paper discusses the sensitivity of the horizontal and vertical scales of extratropical eddies when criticality is varied in a dry, primitive-equation, general circulation model. Criticality is a measure of extratropical isentropic slope and when defined appropriately its value is often close to 1 for Earth's climate. The model is forced by a Newtonian relaxation of temperature to a prescribed temperature profile, and criticality is increased by increasing the thermal relaxation rate on the mean flow. When criticality varies near 1, it is shown that there exists a weakly nonlinear regime in which the eddy scale increases with criticality without involving an inverse cascade, while at the same time the Rossby radius may in fact decrease. The quasigeostrophic instability of the Charney problem is revisited. It is demonstrated that both the horizontal and vertical scales of the most unstable wave depend on criticality, and simple estimates for the two scales are obtained. The authors reconcile the opposite trends of the eddy scale and Rossby radius and obtain an estimate for the eddy scale in terms of the Rossby radius and criticality that is broadly consistent with simulations.NSFNOA

Equilibration of a baroclinic planetary atmosphere toward the limit of vanishing bottom friction

This is the author accepted manuscript. The final version is available from the American Meteorological Society via the DOI in this record.This paper discusses whether and how a baroclinic atmosphere can equilibrate with very small bottom friction in a dry, primitive equation, general circulation model. The model is forced by a Newtonian relaxation of temperature to a prescribed temperature profile, and it is damped by a linear friction near the lower boundary. When friction is decreased by four orders of magnitude, kinetic energy dissipation by friction gradually becomes negligible,while “energy recycling” becomes dominant. In this limit kinetic energy is converted back into potential energy at the largest scales, thus closing the energy cycle without significant frictional dissipation. The momentum fluxes are of opposite sign in the upper and lower atmosphere: in the upper atmosphere, eddies converge momentum into the westerly jets, however, in the lower atmosphere, the eddies diverge momentum out of the westerly jets. The secondary circulation driven by the meridional eddy momentum fluxes thus acts to increase the baroclinicity of the westerly jet. This regime may be relevant for the Jovian atmosphere, where the frictional time scale may be much larger than the radiative damping time scale.This work was funded by the NSF under grant 656 AGS-1144302 and the NOAA under grant NA08OAR4320752

Towards a Reliable Framework of Uncertainty-Based Group Decision Support System

This study proposes a framework of Uncertainty-based Group Decision Support System (UGDSS). It provides a platform for multiple criteria decision analysis in six aspects including (1) decision environment, (2) decision problem, (3) decision group, (4) decision conflict, (5) decision schemes and (6) group negotiation. Based on multiple artificial intelligent technologies, this framework provides reliable support for the comprehensive manipulation of applications and advanced decision approaches through the design of an integrated multi-agents architecture.Comment: Accepted paper in IEEE-ICDM2010; Print ISBN: 978-1-4244-9244-

Experimental study on loss-prevention performance of oil-based drilling fluids

Compared to the water-based drilling fluids, lost circulation is more prone to occur when drilling with oil-based drilling fluids and it is difficult to deal with this problem on the drilling site for lack of high-efficiency lost circulation materials. In order to solve this technical problem, the principles of pressure resistance plugging technology of oil-based drilling fluids was firstly investigated according to the force-chain principle of granular matter mechanics, and rigid bridging particles, elastic packing particles and micro fibers could synergistically form fracture tight sealing zones with strong force-chain network to strengthen the lost circulation prevention ability of oil-based drilling fluids. Based on the principle above, novel loss-prevention materials were finally developed for oil-based drilling fluids by optimizing different plugging agents. Experimental results show that novel loss-prevention materials could be compatible with other components of oil-based drilling fluids. The oil-based drilling fluids with high sealing capacity could be optimized by adding novel loss-prevention materials, and it exhibits good rheological behavior with a low PPT filtration of 11.4 mL and excellent lost circulation prevention ability to strengthen the wellbore while drilling

FAST: Improving Controllability for Text Generation with Feedback Aware Self-Training

Controllable text generation systems often leverage control codes to direct various properties of the output like style and length. Inspired by recent work on causal inference for NLP, this paper reveals a previously overlooked flaw in these control code-based conditional text generation algorithms. Spurious correlations in the training data can lead models to incorrectly rely on parts of the input other than the control code for attribute selection, significantly undermining downstream generation quality and controllability. We demonstrate the severity of this issue with a series of case studies and then propose two simple techniques to reduce these correlations in training sets. The first technique is based on resampling the data according to an example's propensity towards each linguistic attribute (IPS). The second produces multiple counterfactual versions of each example and then uses an additional feedback mechanism to remove noisy examples (feedback aware self-training, FAST). We evaluate on 3 tasks -- news headline, meta review, and search ads generation -- and demonstrate that FAST can significantly improve the controllability and language quality of generated outputs when compared to state-of-the-art controllable text generation approaches

Deep-sea coral evidence for lower Southern Ocean surface nitrate concentrations during the last ice age

The Southern Ocean regulates the ocean’s biological sequestration of CO_2 and is widely suspected to underpin much of the ice age decline in atmospheric CO_2 concentration, but the specific changes in the region are debated. Although more complete drawdown of surface nutrients by phytoplankton during the ice ages is supported by some sediment core-based measurements, the use of different proxies in different regions has precluded a unified view of Southern Ocean biogeochemical change. Here, we report measurements of the ^(15)N/^(14)N of fossil-bound organic matter in the stony deep-sea coral Desmophyllum dianthus, a tool for reconstructing surface ocean nutrient conditions. The central robust observation is of higher ^(15)N/^(14)N across the Southern Ocean during the Last Glacial Maximum (LGM), 18–25 thousand years ago. These data suggest a reduced summer surface nitrate concentration in both the Antarctic and Subantarctic Zones during the LGM, with little surface nitrate transport between them. After the ice age, the increase in Antarctic surface nitrate occurred through the deglaciation and continued in the Holocene. The rise in Subantarctic surface nitrate appears to have had both early deglacial and late deglacial/Holocene components, preliminarily attributed to the end of Subantarctic iron fertilization and increasing nitrate input from the surface Antarctic Zone, respectively

A Behavioral Foundation of Satiation and Habituation

Tastes change over time. People’s tastes are distorted through two channels: satiation formation and habit formation. In this paper, we develop a theoretical foundation of satiation and habituation by an axiomatic approach. Our theory is based on a hierarchy of preference conditions called compensation independence. The behavioral assumption underlying the preference conditions are the psychological compensation of human beings. I flesh out an axiomatic system for general models of satiation and habit formation, which contains many functional forms in the literature as special cases. Moreover, I advance the axiomatization to accommodate the linear representations of satiation and habit formation that are prevailing in the literature. This paper contributes to the birth of a new generation of the behavioral foundation for modeling satiation and habit formation, which might improve on the current state of the art in understanding people’s tastes over time and preferences. Theoretically, this study contributes to the vein of time-nonseparable preferences