Results 61 to 70 of about 71,699 (272)

Foreign labor, peer‐networking and agricultural efficiency in the Italian dairy sector

Agribusiness, EarlyView.
Abstract While the presence of immigrants in the agricultural sector is widely acknowledged, the empirical evidence on its economic consequences is lacking, especially from a microeconomic perspective. Using the Farm Accountancy Data Network panel data for Italian dairy farms in the period 2008–2018, the present study investigates the relationship ...
Federico Antonioli, Simone Severini, Mauro Vigani   +2 more
wiley   +1 more source

Interpretability and Representability of Commutative Algebra, Algebraic Topology, and Topological Spectral Theory for Real‐World Data

Advanced Intelligent Discovery, EarlyView.
This article investigates how persistent homology, persistent Laplacians, and persistent commutative algebra reveal complementary geometric, topological, and algebraic invariants or signatures of real‐world data. By analyzing shapes, synthetic complexes, fullerenes, and biomolecules, the article shows how these mathematical frameworks enhance ...
Yiming Ren, Guo‐Wei Wei
wiley   +1 more source

Alternating Least-Squares for Low-Rank Matrix Reconstruction [PDF]

, 2011
For reconstruction of low-rank matrices from undersampled measurements, we develop an iterative algorithm based on least-squares estimation. While the algorithm can be used for any low-rank matrix, it is also capable of exploiting a-priori knowledge of ...
Chatterjee, Saikat, Jansson, Magnus, Sundin, Martin, Zachariah, Dave   +3 more
core   +1 more source

Remarks on some norm inequalities for positive semidefinite matrices and questions of Bourin

, 2017
Let A and B be positive semidefinite matrices. It is shown that ∥∥AsBp +BqAt∥∥2 ∥∥AsBp +AtBq∥∥2 for all positive real numbers s,t, p,q for which ∣∣∣ s s+ t − 1 2 ∣∣∣+ ∣∣∣ p p+q − 1 2 ∣∣∣ 1 2 .
M. Hayajneh, Saja Hayajneh, F. Kıttaneh
semanticscholar   +1 more source

Planning and Control Framework for a Quadruped Robot With Changeable Configuration

Advanced Intelligent Systems, EarlyView.
Multiconfiguration quadruped robots enhance adaptability by switching between mammal‐like and reptile‐like morphologies. This study presents a nonlinear constraint‐based motion planner integrated with a hierarchical whole‐body controller, enabling robust configuration switching and locomotion on complex terrains. Experiments on slopes, irregular bricks,
Guanglin Lu, Yifan Zhang, Teng Chen, Xuewen Rong, Guoteng Zhang, Yibin Li   +5 more
wiley   +1 more source

Bounds of the logarithmic mean [PDF]

, 2013
We give tight bounds for logarithmic mean. We also give new Frobenius norm inequalities for two positive semidefinite matrices. In addition, we give some matrix inequalities on matrix power mean.Comment: The second assertion in (i) of Proposition 5.2 was
Furuichi, Shigeru, Yanagi, Kenjiro
core   +2 more sources

A norm inequality for pairs of commuting positive semidefinite matrices [PDF]

, 2014
For $k=1,\ldots,K$, let $A_k$ and $B_k$ be positive semidefinite matrices such that, for each $k$, $A_k$ commutes with $B_k$. We show that, for any unitarily invariant norm, \[ |||\sum_{k=1}^K A_kB_k||| \le ||| (\sum_{k=1}^K A_k)\;(\sum_{k=1}^K B_k)|||. \
K. Audenaert
semanticscholar   +1 more source

Quantum Carnot Bound from Petz Recovery Maps

Advanced Physics Research, EarlyView.
A quantum bound (ηP$\eta_P$, the Petz Limit) is derived for the efficiency (η$\eta$) of a heat engine utilizing two‐level quantum systems (qubits) as the working substance. This limit, based on Petz recovery maps, is stricter than the classical Carnot limit (ηC$\eta_C$) for irreversible cycles.
Douglas Mundarain, Kevin Araya‐Sossa, Mario Miranda‐Rojas   +2 more
wiley   +1 more source

A Parallel Approximation Algorithm for Positive Semidefinite Programming

, 2011
Positive semidefinite programs are an important subclass of semidefinite programs in which all matrices involved in the specification of the problem are positive semidefinite and all scalars involved are non-negative.
Jain, Rahul, Yao, Penghui
core   +1 more source

A class of positive semidefinite matrices

Linear Algebra and its Applications, 1987
It is a known fact that, given a positive definite matrix \(y_{ij}\), the ``standardized'' matrix \(y_{ij}(y_{ii}y_{jj})^{-}\) is again positive definite. The authors investigate more general standardization methods of the form \(a_{ij}(\alpha)y_{ij}\) where \(\alpha\) is a positive number and \(a_{ij}(\alpha)=(\phi (x_ i,\alpha)+\phi (x_ j,\alpha))^{-}
Russell, A.M., Upton, C.J.F.
openaire   +2 more sources