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Berry-Phase and Symmetry of the Ground State in Dynamical Jahn-Teller Systems [article]

Paolo De Los Rios, Nicola Manini
1997 arXiv   pre-print
Moreover, we introduce a new class of Jahn-Teller systems with no Berry phase, as a generalization of the basic icosahedral H ⊗ h case.  ...  We show through selected examples, relevant to the physics of fullerene ions, that the presence of a Berry phase in dynamical Jahn-Teller systems does not guarantee the degeneracy of the ground state,  ...  A particularly new and surprising one has been demonstrated recently: the possibility of a change in symmetry of the ground state.  ... 
arXiv:cond-mat/9709094v1 fatcat:ybmomed7nvg4xhraitxm62fyh4

Joint Optimization of Tree-based Index and Deep Model for Recommender Systems [article]

Han Zhu, Daqing Chang, Ziru Xu, Pengye Zhang, Xiang Li, Jie He, Han Li, Jian Xu, Kun Gai
2019 arXiv   pre-print
Besides, we come up with a novel hierarchical user preference representation utilizing the tree index hierarchy.  ...  Online A/B test results at a display advertising platform also demonstrate the effectiveness of the proposed method in production environments.  ...  Thank Huimin Yi, Yang Zheng and Xianteng Wu for implementing the key components of the training and inference platform.  ... 
arXiv:1902.07565v2 fatcat:ras3hhsvancynkhis4uysyq64i

Learning Tree-based Deep Model for Recommender Systems

Han Zhu, Xiang Li, Pengye Zhang, Guozheng Li, Jie He, Han Li, Kun Gai
2018 Proceedings of the 24th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining - KDD '18  
Online A/B test results in Taobao display advertising platform also demonstrate the effectiveness of the proposed method in production environments.  ...  ., interactions through deep neural networks, because of the calculation cost.  ...  Thank Huimin Yi, Yang Zheng and Xianteng Wu for implementing the key components of the training and inference platform.  ... 
doi:10.1145/3219819.3219826 dblp:conf/kdd/ZhuLZLHLG18 fatcat:zp7goqjacrgvbglzq2tv2gmapi

Berry Phase and the Symmetry of the Vibronic Ground State in Dynamical Jahn-Teller Systems [article]

Nicola Manini, Paolo De Los Rios
1999 arXiv   pre-print
However, the H x h icosahedral case, relevant for the physics of fullerene ions, provides a first example of linear coupling leading, at strong coupling, to a change in symmetry of the ground state to  ...  Due to the frequent presence of a Berry phase, in most cases of dynamical Jahn-Teller systems the symmetry of the ground state is the same as that of the electronic state.  ...  of new systems which call for a revision of a number of commonly accepted beliefs.  ... 
arXiv:cond-mat/9901097v1 fatcat:7lzv55yghng4pb2nb56adj4jc4

The rôle of the Berry phase in dynamical Jahn-Teller systems

Nicola Manini, Paolo De Los Rios
1998 Journal of Physics: Condensed Matter  
The presence/absence of a Berry phase depends on the topology of the manifold of dynamical Jahn-Teller potential minima.  ...  Its absence can, but does not necessarily, lead to a nondegenerate ground state.  ...  by the realization of new systems which call for a revision of a number of commonly accepted beliefs.  ... 
doi:10.1088/0953-8984/10/38/009 fatcat:beel42vixrcktmipomyxbyx5sy

Identifying Rare and Subtle Behaviors: A Weakly Supervised Joint Topic Model

Timothy M. Hospedales, Jian Li, Shaogang Gong, Tao Xiang
2011 IEEE Transactions on Pattern Analysis and Machine Intelligence  
We extensively validate our approach on two standard public-space datasets where it clearly outperforms a batch of contemporary alternatives.  ...  One of the most interesting and desired capabilities for automated video behaviour analysis is the identification of rarely occurring and subtle behaviours.  ...  We next show how to learn a WS-JTM model (training) and use the learned model to classify new data (testing).  ... 
doi:10.1109/tpami.2011.81 pmid:21519099 fatcat:tcnngkr4qra2jpfzjbz6kotmba

Simulation of one-dimensional quantum systems with a global SU(2) symmetry

Sukhwinder Singh, Huan-Qiang Zhou, Guifre Vidal
2010 New Journal of Physics  
We propose a refined matrix product state representation for many-body quantum states that are invariant under SU(2) transformations, and indicate how to extend the time-evolving block decimation (TEBD  ...  The resulting algorithm is tested in a critical quantum spin chain and shown to be significantly more efficient than the standard TEBD.  ...  A total spin basis (TSB) | [V ] jtm ∈ V satisfies the eigenvalue relations S 2 | [V ] jtm = j(j + 1)| [V ] jtm , S z | [V ] jtm = m| [V ] jtm , (1) and is associated with the direct sum decomposition  ... 
doi:10.1088/1367-2630/12/3/033029 fatcat:i6odoszsuvdllawzksbigjlzxe

Co-Optimized Analysis and Design of Electric and Natural Gas Infrastructures

Santiago Lemos-Cano, James McCalley
2019 Energies  
Results show that the model provides an accurate operational representation of the integrated system, and, therefore, enhances the expansion planning process.  ...  A 26 node integrated gas-electric system for the Eastern Region of the United States is used to demonstrate the model's capabilities.  ...  This design proposes a robust electric transmission grid configured as a ring between MISO and PJM to move the large amounts of electricity produced in the new wind farms.  ... 
doi:10.3390/en12102012 fatcat:7lfd4x555jbmphajb623udypce

Forest-based Deep Recommender

Chao Feng, Defu Lian, Zheng Liu, Xing Xie, Le Wu, Enhong Chen
2022 Proceedings of the 45th International ACM SIGIR Conference on Research and Development in Information Retrieval  
When learning node representation of each tree, we have to satisfy the max-heap assumption as much as possible and mimic beam search behavior over the tree in the training stage.  ...  The recently proposed tree-based deep recommendation models alleviate the problem by directly learning tree structure and representations under the guidance of recommendation objectives.  ...  ACKNOWLEDGMENTS The work was supported by grants from the National Key R&D Program of China under Grant No. 2020AAA0103800, the National Natural Science Foundation of China (No. 61976198 and 62022077).  ... 
doi:10.1145/3477495.3531980 fatcat:2zgex3lmqrczpissfnf24lsqdq

Dynamical Jahn-Teller effect and Berry phase in positively charged fullerenes: Basic considerations

Paolo De Los Rios, Nicola Manini, Erio Tosatti
1996 Physical Review B (Condensed Matter)  
We study in particular the special equal-coupling case (g_2=g_4), which is reduced to the motion of a particle on a 5-dimensional sphere.  ...  In the icosahedral molecule, the final outcome assesses the presence/absence of a Berry phase of π for the h_u hole coupled to G_g/H_h vibrations.  ...  Therefore, a general representation of O(3) decomposes into a finite number of representations of I h [21] .  ... 
doi:10.1103/physrevb.54.7157 pmid:9984337 fatcat:h5ykaqfi5ncvrgbn36ddaytdlm

Multi-Dimensional Separation of Concerns and the Hyperspace Approach [chapter]

Harold Ossher, Peri Tarr
2002 Software Architectures and Component Technology  
This paper discusses multi-dimensional separation of concerns in general, our particular approach to providing it, called hyperspaces, and our support for hyperspaces in Java™, called Hyper/J™.  ...  A key reason is that one needs different decompositions according to different concerns at different times, but most languages and modularization approaches support only one "dominant" kind of modularization  ...  It contains a set of tools that share a common representation of expressions.  ... 
doi:10.1007/978-1-4615-0883-0_10 fatcat:s5sesx7gdvednp6lv67nblmahy

Workflow automation based on OSI job transfer and manipulation

Marten J. van Sinderen, Stef M.M. Joosten, Cléver R. Guareis de Farias
1999 Computer Standards & Interfaces  
This paper shows that Workflow Management Systems (WFMS) and a data communication standard called Job Transfer and Manipulation (JTM) are built on the same concepts, even though different words are used  ...  The paper analyses the correspondence of workflow concepts and JTM concepts. Besides, the correspondence of relationships between those concepts is analysed as well.  ...  Acknowledgements We wish to thank Mark de Weger and Duane Truex for their useful comments on earlier versions of this paper. Cléver Ricardo Guareis de Farias is supported by CNPq -Brazil.  ... 
doi:10.1016/s0920-5489(99)00019-7 fatcat:3wez3skxbbd7hm3szqf2zrcppa

The Truth, the Whole Truth, and Nothing But the Truth

João P. Martins
1991 The AI Magazine  
the Queen said in a pitying tone. 'Try again: draw a long breadth, and shut your eyes.' Alice laughed. 'There's no use trying,' she said: 'one can't believe i m p o s s i b l e things.'  ...  'When I was your age, I always did it for half-an-hour a day. Why, sometimes I've believed as many as six impossible things before breakfast.' Lewis Carroll, Through the Looking Glass  ...  Cravo for her help and fruitful discussions during compilation of this bibliography.  ... 
doi:10.1609/aimag.v11i4.866 dblp:journals/aim/Martins91 fatcat:23c7bhdz3jhdxhfnkjwugn6qme

Page 1579 of Mathematical Reviews Vol. 45, Issue 6 [page]

1973 Mathematical Reviews  
In a sense, this generalization improves the linear version as it presents UQE(J™) by a finite number of generators and relations.  ...  compound linear envelope UCE(J™).  ... 

Page 997 of None Vol. 105, Issue 3 [page]

1957 None  
If the calculation is first done in the cases of a single 7’ neutron, the transformation is simpler, the 9—J symbol being replaced by a Racah coefficient® 4 (j™aJ)7'J ge m+) j™(ay’J1')7'J) ey GBI) ji hima  ...  New York, to be published). 997 When we perform this transformation together with a similar transformation on the wave function to the right of Vin, min in (5), we obtain expression (5) in the form mn  ... 
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