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List-Decodable Mean Estimation in Nearly-PCA Time [article]

Ilias Diakonikolas, Daniel M. Kane, Daniel Kongsgaard, Jerry Li, Kevin Tian
2020 arXiv   pre-print
Daniel Kane is supported by NSF CAREER Award ID 1553288 and a Sloan fellowship. Kevin Tian is supported by NSF CAREER Award CCF-1844855 and NSF Grant CCF-1955039.  ... 
arXiv:2011.09973v1 fatcat:bfvpsfxse5f6lfkuwd4kahlhku

Inverse scattering transform for the integrable nonlocal Lakshmanan-Porsezian-Daniel equation [article]

Wei-Kang Xun, Shou-Fu Tian
2020 arXiv   pre-print
In this work, a generalized nonlocal Lakshmanan-Porsezian-Daniel (LPD) equation is introduced, and its integrability as an infinite dimensional Hamilton dynamic system is established.  ...  In this work, we consider IST for the integrable nonlocal Lakshmanan-Porsezian-Daniel (LPD) equation q t (x, t) + 1 2 iq xx (x, t) − iγq 2 (x, t)q * (−x, t) − δH[q(x, t)] = 0, (1.1) where H[q(x, t)] =  ... 
arXiv:2005.04011v1 fatcat:vcnc7gakz5dizduxf3nc4dbzc4

Nanoscale movements of cellulose microfibrils in primary cell walls

Tian Zhang, Dimitrios Vavylonis, Daniel M. Durachko, Daniel J. Cosgrove
2017 Nature Plants  
The growing plant cell wall is commonly considered a fiber-reinforced structure whose strength, extensibility and anisotropy depend on the orientation of crystalline cellulose microfibrils, their bonding to the polysaccharide matrix, and matrix viscoelasticity 1-4 . Structural reinforcement of the wall by stiff cellulose microfibrils is central to contemporary models of plant growth, mechanics, and meristem dynamics 4-12 . Although passive microfibril reorientation during wall extension has
more » ... inferred from theory and from bulk measurements 13-15 , nm-scale movements of individual microfibrils have not been directly observed. Here we combined nm-scale imaging of wet cell walls by atomic force microscopy (AFM) with a stretching device and endoglucanase treatment that induces wall stress relaxation and creep, mimicking wall behaviors during cell growth. Microfibril movements during forced mechanical extensions differ from those during creep of the enzymatically-loosened wall. In addition to passive angular reorientation, we observed a diverse repertoire of microfibril movements that reveal the spatial scale of molecular connections between microfibrils. Our results show that wall loosening alters microfibril connectivity, enabling microfibril dynamics not seen during mechanical stretch. These insights into microfibril movements and connectivities need to be incorporated into refined models of plant cell wall structure, growth and morphogenesis. To visualize microfibril movements, we prepared cell-free strips of the outer epidermal wall of onion (Figure 1a ) because this material is suitable for both tensile tests 14,16,17 and highresolution AFM imaging of individual microfibrils at the inner (newly deposited) cell wall surface 18 . AFM also let us assess the wall surface by nanomechanical methods. To modulate Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: http://www.nature.
doi:10.1038/nplants.2017.56 pmid:28452988 pmcid:PMC5478883 fatcat:uggjyz6ybbbe5pjzpvjmwa7rty

Do Unions Affect Innovation?

Daniel Bradley, Incheol Kim, Xuan Tian
2017 Management science  
Tian and Wang (2015) show that labor unions deter takeover bids. Several papers directly examine the impact of labor unions on investment.  ...  However, He and Tian (2013) show that analysts stifle innovation because analysts impose short-term pressure on managers to meet earnings targets.  ... 
doi:10.1287/mnsc.2015.2414 fatcat:bc7uej2nabd7fm2q2ygpg55lhq

A Search for the Underlying Equation Governing Similar Systems [article]

Changwei Loh, Daniel Schneegass, Pengwei Tian
2019 arXiv   pre-print
We show a data-driven approach to discover the underlying structural form of the mathematical equation governing the dynamics of multiple but similar systems induced by the same mechanisms. This approach hinges on theories that we lay out involving arguments based on the nature of physical systems. In the same vein, we also introduce a metric to search for the best candidate equation using the datasets generated from the systems. This approach involves symbolic regression by means of genetic
more » ... gramming and regressions to compute the strength of the interplay between the extrinsic parameters in a candidate equation. We relate these extrinsic parameters to the hidden properties of the data-generating systems. The behavior of a new similar system can be predicted easily by utilizing the discovered structural form of the general equation. As illustrations, we apply the approach to identify candidate structural forms of the underlying equation governing two cases: the changes in a sensor measurement of degrading engines; and the search for the governing equation of systems with known variations of an intrinsic parameter.
arXiv:1908.10673v1 fatcat:kqickewrf5ekdi3gbwou5kg6oy

Rainbow Ramsey problems for the Boolean lattice [article]

Fei-Huang Chang, Dániel Gerbner, Wei-Tian Li, Abhishek Methuku, Dániel Nagy, Balázs Patkós, Máté Vizer
2020 arXiv   pre-print
We address the following rainbow Ramsey problem: For posets P,Q what is the smallest number n such that any coloring of the elements of the Boolean lattice B_n either admits a monochromatic copy of P or a rainbow copy of Q. We consider both weak and strong (non-induced and induced) versions of this problem. We also investigate related problems on (partial) k-colorings of B_n that do not admit rainbow antichains of size k.
arXiv:1809.08629v2 fatcat:nbzgukvjrjdehovqbixtrlm3vu

Author Correction: Nanoscale movements of cellulose microfibrils in primary cell walls

Tian Zhang, Dimitrios Vavylonis, Daniel M. Durachko, Daniel J. Cosgrove
2020 Nature Plants  
A Correction to this paper has been published: https://doi.org/10.1038/nplants.2017.56.
doi:10.1038/s41477-020-00821-w pmid:33244172 fatcat:o2jesrsbajfmza7nrzi6fn22ku

Predicting the Number of Future Events

Qinglong Tian, Fanqi Meng, Daniel J. Nordman, William Q. Meeker
2020 figshare.com  
This paper describes prediction methods for the number of future events from a population of units associated with an on-going time-to-event process. Examples include the prediction of warranty returns and the prediction of the number of future product failures that could cause serious threats to property or life. Important decisions such as whether a product recall should be mandated are often based on such predictions. Data, generally right-censored (and sometimes left truncated and
more » ... ored), are used to estimate the parameters of a time-to-event distribution. This distribution can then be used to predict the number of events over future periods of time. Such predictions are sometimes called within-sample predictions and differ from other prediction problems considered in most of the prediction literature. This paper shows that the plug-in (also known as estimative or naive) prediction method is not asymptotically correct (i.e., for large amounts of data, the coverage probability always fails to converge to the nominal confidence level). However, a commonly used prediction calibration method is shown to be asymptotically correct for within-sample predictions, and two alternative predictive-distribution-based methods that perform better than the calibration method are presented and justified.
doi:10.6084/m9.figshare.13242447.v1 fatcat:ffalylxevzb2ldotfev3jiuosm

Density Effects on the Post-shock Turbulence Structure and Dynamics [article]

Yifeng Tian, Farhad A. Jaberi, Daniel Livescu
2019 arXiv   pre-print
Our earlier numerical studies of variable density STI have revealed some important new features of velocity and scalar statistics in this setup (Tian et al., 2017b (Tian et al., , 2018 .  ...  To ensure that all the turbulence length scales are well resolved, a grid convergence test was conducted in Tian et al. (2017a) .  ... 
arXiv:1908.05327v1 fatcat:evjjehf5tbcg3p2z6yabw2e5hu

A Review on Laser Powder Bed Fusion of Inconel 625 Nickel-Based Alloy

Zhihua Tian, Chaoqun Zhang, Dayong Wang, Wen Liu, Xiaoying Fang, Daniel Wellmann, Yongtao Zhao, Yingtao Tian
2019 Applied Sciences  
The Inconel 625 (IN625) superalloy has a high strength, excellent fatigue, and creep resistance under high-temperature and high-pressure conditions, and is one of the critical materials used for manufacturing high-temperature bearing parts of aeroengines. However, the poor workability of IN625 alloy prevents IN625 superalloy to be used in wider applications, especially in applications requiring high geometrical complexity. Laser powder bed fusion (LPBF) is a powerful additive manufacturing
more » ... ss which can produce metal parts with high geometrical complexity and freedom. This paper reviews the studies that have been done on LPBF of IN625 focusing on the microstructure, mechanical properties, the development of residual stresses, and the mechanism of defect formation. Mechanical properties such as microhardness, tensile properties, and fatigue properties reported by different researchers are systematically summarized and analyzed. Finally, the remaining issues and suggestions on future research on LPBF of IN625 alloy parts are put forward.
doi:10.3390/app10010081 fatcat:feehwmuy45cingcegfkrbggjpq

Regression-based projection for learning Mori–Zwanzig operators [article]

Yen Ting Lin, Yifeng Tian, Daniel Livescu
2022 arXiv   pre-print
We propose to adopt statistical regression as the projection operator to enable data-driven learning of the operators in the Mori--Zwanzig formalism. We present a principled algorithm to extract the Markov and memory operators for any regression models. We show that the choice of linear regression results in a recently proposed data-driven learning algorithm based on Mori's projection operator, which can be considered as a higher-order approximate Koopman learning method. We show that more
more » ... ssive, potentially nonlinear regression models naturally fill in the gap between the highly idealized and computationally efficient Mori's projection operator and the most optimal yet computationally infeasible Zwanzig projection operator. We performed numerical experiments and extracted the operators for an array of regression-based projections, including linear, polynomial, spline, and neural-network-based regression, showing a progressive improvement as the complexity of the regression model increased. Our proposition provides a general framework to extract memory-dependent corrections and can be readily applied to an array of data-driven learning methods for stationary dynamical systems in the literature.
arXiv:2205.05135v1 fatcat:m7nfvg2qsnhypnvtkfnwcmet2a

DMF - A New Biofuel Candidate [chapter]

Guohong Tian, Ritchie Daniel, Hongming Xu
2011 Biofuel Production-Recent Developments and Prospects  
How to reference In order to correctly reference this scholarly work, feel free to copy and paste the following: Guohong Tian, Ritchie Daniel and Hongming Xu (2011).  ... 
doi:10.5772/21738 fatcat:34du5x4panbgxmgx3bj2wenw4i

Method Proxy-Based AOP in Scala

Daniel Spiewak, Tian Zhao
2009 Journal of Object Technology  
VOL 8, NO. 7 JOURNAL OF OBJECT TECHNOLOGY 169 setX(int x) { 1 The source code is available at: http://www.codecommit.com/scala-aop.zip Cite this article as follows: Daniel Spiewak and Tian Zhao: Method  ...  Tian Zhao is an associate professor of Computer Science at the University of Wisconsin -Milwaukee.  ... 
doi:10.5381/jot.2009.8.7.a5 fatcat:5unrokqhanfz5lcum7xvvnl6uq

ScalaQL: Language-Integrated Database Queries for Scala [chapter]

Daniel Spiewak, Tian Zhao
2010 Lecture Notes in Computer Science  
One of the most ubiquitous elements of modern computing is the relational database. Very few modern applications are created without some sort of database backend. Unfortunately, relational database concepts are fundamentally very different from those used in generalpurpose programming languages. This creates an impedance mismatch between the the application and the database layers. One solution to this problem which has been gaining traction in the .NET family of languages is
more » ... d Queries (LINQ). That is, the embedding of database queries within application code in a way that is statically checked and type safe. Unfortunately, certain language changes or core design elements were necessary to make this embedding possible. We present a framework which implements this concept of type safe embedded queries in Scala without any modifications to the language itself. The entire framework is implemented by leveraging existing language features (particularly for-comprehensions).
doi:10.1007/978-3-642-12107-4_12 fatcat:mqpkishbzzewvl2grxjwbl45uy

Identifiability and numerical algebraic geometry

Daniel J. Bates, Jonathan D. Hauenstein, Nicolette Meshkat, Fang-Bao Tian
2019 PLoS ONE  
Writing -original draft: Daniel J. Bates, Jonathan D. Hauenstein, Nicolette Meshkat. Writing -review & editing: Daniel J. Bates, Jonathan D.  ...  Software: Daniel J. Bates, Jonathan D. Hauenstein, Nicolette Meshkat. Supervision: Nicolette Meshkat. Validation: Daniel J. Bates, Jonathan D. Hauenstein, Nicolette Meshkat.  ... 
doi:10.1371/journal.pone.0226299 pmid:31834904 pmcid:PMC6910699 fatcat:3pr3lz4mr5aj7az77v3wa4rf7q
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