Paper Surveys Recent Progress Research Articles

Video Unsupervised Domain Adaptation with Deep Learning: A Comprehensive Survey

Video analysis tasks such as action recognition have received increasing research interest with growing applications in fields such as smart healthcare, thanks to the introduction of large-scale datasets and deep learning-based representations. However, video models trained on existing datasets suffer from significant performance degradation when deployed directly to real-world applications due to domain shifts between the training public video datasets (source video domains) and real-world videos (target video domains). Further, with the high cost of video annotation, it is more practical to use unlabeled videos for training. To tackle performance degradation and address concerns in high video annotation cost uniformly, the video unsupervised domain adaptation (VUDA) is introduced to adapt video models from the labeled source domain to the unlabeled target domain by alleviating video domain shift, improving the generalizability and portability of video models. This paper surveys recent progress in VUDA with deep learning. We begin with the motivation of VUDA, followed by its definition, and recent progress of methods for both closed-set VUDA and VUDA under different scenarios, and current benchmark datasets for VUDA research. Eventually, future directions are provided to promote further VUDA research. The repository of this survey is provided at https://github.com/xuyu0010/awesome-video-domain-adaptation.

Large simplicial complexes: universality, randomness, and ampleness

The paper surveys recent progress in understanding geometric, topological and combinatorial properties of large simplicial complexes, focusing mainly on ampleness, connectivity and universality (Even-Zohar et al. in Eur J Math 8(1):1–32, 2022; Farber and Mead in Topol Appl 272(22):107065, 2020; Farber et al. in J Appl Comput Topol 5(2):339–356, 2021). In the first part of the paper we concentrate on r-ample simplicial complexes which are high dimensional analogues of the r-e.c. graphs introduced originally by Erdős and Rényi (Acta Math Acad Sci Hungar 14:295–315, 1963), see also Bonato (Contrib Discrete Math 4(1):40–53, 2009). The class of r-ample complexes is useful for applications since these complexes allow extensions of subcomplexes of certain type in all possible ways; besides, r-ample complexes exhibit remarkable robustness properties. We discuss results about the existence of r-ample complexes and describe their probabilistic and deterministic constructions. The properties of random simplicial complexes in medial regime (Farber and Mead 2020) are important for this discussion since these complexes are ample, in certain range. We prove that the topological complexity of a random simplicial complex in the medial regime satisfies TC(X)≤4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ extsf{TC}(X)\\le 4$$\\end{document}, with probability tending to 1 as n→∞\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$n\\rightarrow \\infty $$\\end{document}. There exists a unique (up to isomorphism) ∞\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\infty $$\\end{document}-ample complex on countable set of vertexes (the Rado complex), and the second part of the paper surveys the results about universality, homogeneity, indestructibility and other important properties of this complex. The Appendix written by J.A. Barmak discusses connectivity of conic and ample complexes.

Octonion Internal Space Algebra for the Standard Model

This paper surveys recent progress in our search for an appropriate internal space algebra for the standard model (SM) of particle physics. After a brief review of the existing approaches, we start with the Clifford algebras involving operators of left multiplication by octonions. A central role is played by a distinguished complex structure that implements the splitting of the octonions O=C⊕C3, which reflect the lepton-quark symmetry. Such a complex structure on the 32-dimensional space S of Cℓ10 Majorana spinors is generated by the Cℓ6(⊂Cℓ10) volume form, ω6=γ1⋯γ6, and is left invariant by the Pati–Salam subgroup of Spin(10), GPS=Spin(4)×Spin(6)/Z2. While the Spin(10) invariant volume form ω10=γ1…γ10 of Cℓ10 is known to split S on a complex basis into left and right chiral (semi)spinors, P=12(1−iω6) is interpreted as the projector on the 16-dimensional particle subspace (which annihilates the antiparticles).The standard model gauge group appears as the subgroup of GPS that preserves the sterile neutrino (which is identified with the Fock vacuum). The Z2-graded internal space algebra A is then included in the projected tensor product A⊂PCℓ10P=Cℓ4⊗Cℓ60. The Higgs field appears as the scalar term of a superconnection, an element of the odd part Cℓ41 of the first factor. The fact that the projection of Cℓ10 only involves the even part Cℓ60 of the second factor guarantees that the color symmetry remains unbroken. As an application, we express the ratio mHmW of the Higgs to the W boson masses in terms of the cosine of the theoretical Weinberg angle.

Semi-algebraic sets method in PDE and mathematical physics

This paper surveys recent progress in the analysis of nonlinear partial differential equations using Anderson localization and semi-algebraic sets method. We discuss the application of these tools from linear analysis to nonlinear equations such as the nonlinear Schrödinger equations, the nonlinear Klein–Gordon equations (nonlinear wave equations), and the nonlinear random Schrödinger equations on the lattice. We also review the related linear time-dependent problems.

Electrochromics for energy efficient buildings: Towards long-term durability and materials rejuvenation

Electrochromic devices such as “smart windows” for energy efficient windows must be durable enough for many years of practical use. Typical devices employ films based on W oxide and Ni oxide, and this paper surveys recent progress on durability-related issues for these materials. In the case of W oxide, we discuss the beneficial effects of Ti addition, and we describe recent and unexpected progress concerning galvanostatic rejuvenation of aged W oxide films. For Ni oxide, we report how charge exchange declination during extended voltammetric cycling can be modeled in terms of a power law.

Electrochromics for energy efficient buildings: Towards long-term durability and materials rejuvenation

Electrochromic devices such as “smart windows” for energy efficient windows must be durable enough for many years of practical use. Typical devices employ films based on W oxide and Ni oxide, and this paper surveys recent progress on durability-related issues for these materials. In the case of W oxide, we discuss the beneficial effects of Ti addition, and we describe recent and unexpected progress concerning galvanostatic rejuvenation of aged W oxide films. For Ni oxide, we report how charge exchange declination during extended voltammetric cycling can be modeled in terms of a power law.

Survey: Discovery in Wireless Sensor Networks

Neighbor discovery is a component of communication and access protocols for ad hoc networks. Wireless sensor networks often must operate under a more severe low-power regimen than do traditional ad hoc networks, notably by turning off radio for extended periods. Turning off a radio is problematic for neighbor discovery, and a balance is needed between adequate open communication for discovery and silence to conserve power. This paper surveys recent progress on the problems of neighbor discovery for wireless sensor networks. The basic ideas behind these protocols are explained, which include deterministic schedules of waking and sleeping, randomized schedules, and combinatorial methods to ensure discovery.

Heat Generation and Transport in SOI and GOI Devices

This paper surveys recent progress in our understanding of heat generation and transport in nanoscale transistors. Monte Carlo simulations show that under quasi-ballistic transport conditions, most Joule heat is generated in the device drain. Measurements and modeling find the device thermal resistance scales inversely with device size, reaching well over 100 K/mW for sub-100 nm transistors. This trend is partly also driven by decreased thermal conductivity of ultra-thin films, as well as the increased role of boundary thermal resistance. Somewhat surprisingly, the analysis shows that well-behaved GOI transistors ought to outperform SOI from a thermal viewpoint as well, highlighting the importance of electro-thermal co-design at device length scales approaching 10 nm.

On assertion-based encapsulation for object invariants and simulations

Abstract In object-oriented programming, reentrant method invocations and shared references make it difficult to achieve adequate encapsulation for sound modular reasoning. This tutorial paper surveys recent progress using auxiliary state (ghost fields) to describe and achieve encapsulation. It also compares this technique with encapsulation in the forms provided by separation logic. Encapsulation is assessed in terms of modular reasoning about invariants and simulations.

Multidimensional symmetric stable processes

This paper surveys recent remarkable progress in the study of potential theory for symmetric stable processes. It also contains new results on the two-sided estimates for Green functions, Poisson kernels and Martin kernels of discontinuous symmetric α-stable process in boundedC1,1 open sets. The new results give explicit information on how the comparing constants depend on parameter α and consequently recover the Green function and Poisson kernel estimates for Brownian motion by passing α ↑ 2. In addition to these new estimates, this paper surveys recent progress in the study of notions of harmonicity, integral representation of harmonic functions, boundary Harnack inequality, conditional gauge and intrinsic ultracontractivity for symmetric stable processes. Here is a table of contents. 1. Introduction 2. Green function and Poisson kernel estimates 2.1. Estimates on balls 2.2. Estimates on boundedC1,1 domains 2.3. Estimates on boundedC1,1 open sets 3. Harmonic functions and integral representation 3.1. Two notions of harmonicity 3.2. Martin kernel and Martin boundary 3.3. Integral representation and uniqueness 3.4. Boundary Harnack principle 3.5. Conditional process and its limiting behavior 4. Conditional gauge and intrinsic ultracontractivity

Parallel Algorithms for Sparse Linear Systems

This paper surveys recent progress in the development of parallel algorithms for solving sparse linear systems on computer architectures having multiple processors. Attention is focused on direct methods for solving sparse symmetric positive definite systems, specifically by Cholesky factorization. Recent progress on parallel algorithms is surveyed for all phases of the solution process, including ordering, symbolic factorization, numeric factorization, and triangular solution.

Automatic Robot Programming

Industrial robots require more and more advanced programming tools. After “teaching by showing” techniques, manipulator-level programming languages for describing tasks by sequences of robot operations have emerged, and they to-day become widespread in industry. However, writting manipulatorlevel programs is not easy. This difficulty arises the need for higher level languages, called task-level languages, for describing assembly tasks as sequences of goal spatial relationships between objects. Translating such a description into a manipulator-level program requires to solve three main problems: grasp planning, path planning, and fine notion planning. This paper surveys recent progress toward solving these problems. Task-level languages may deeply transform the way we will program robots in the future, and they contribute to better CAD/CAM integration.

Overview of digital facsimile coding techniques in Japan

This paper surveys recent progress in digital facsimile coding techniques in Japan. First, the digital facsimile coding techniques are classified into two major categories: information-preserving coding and non-information-preserving coding. Second, various two-dimensional coding algorithms which fall into the category of information-preserving coding are selected and discussed. Two-dimensional coding is divided into two categories: simultaneous coding of n lines and line-by-line sequential coding. Third, the READ coding scheme, which was proposed by Japan to CCITT SG XIV as the standard of two-dimensional coding, is explained in detail. Fourth, recent developments concerning non-information-preserving coding are explained. Finally, related coding techniques and applications of digital facsimile coding are briefly described.

ANGLE-RESOLVED PHOTOEMISSION FROM SURFACES AND ADSORBATES

In the application of angle-resolved photoemission spectroscopy to the study of surface systems, two basic kinds of information are sought : (1) the positions of atoms in the surface and in adsorbed species ; (2) the nature of the electronic states characteristic of free surfaces and those involved in the chemical binding of adsorbates. This paper surveys recent progress in both of these atomic and electronic aspects of the field. An example of an atomic-structure investigation using angle-resolved photoemission is the determination of the orientation of CO molecules adsorbed on Ni. In many studies in the valence band region, the atomic and electronic information is not readily separable, since a complete description of the electronic structure (and therefore the valence band spectra) requires a knowledge of the atomic positions. The role here of semiempirical calculations of two-dimensional band structures (E(k||) dispersion relations) using the Linear-Combination of Atomic Orbitals (LCAO) or pseudopotential methods is emphasized. As examples, angle-resolved photoemission measurements of the E(k||) relations for surface states on GaAs(110) and Cl-induced states on Si(111) are compared with model calculations. Parity considerations and also anisotropies in core level photoemission from two-dimensional systems are discussed.

On the Application of Systems Methodology to Economic and Organizational Management of Integrated Industrial Complexes

The combined use of interpretive structural modeling and decision analysis within an appropriate methodological framework offers much promise for the economic and organizational management of large integrated industrial complexes. A symbiotic blending of technical, administrative, political and societal concerns is necessary for the determination and incorporation of direct and indirect benefits and costs and nonquantifiable societal impacts into a hoped for standard normative procedure for assessing the worth of policies for technological innovations in industrial complexes. This paper surveys recent progress relative to these issues and discusses possible directions for future efforts directed at this needed synthesis.

Recent progress and problems on the Bartnik quasi-local mass

This paper surveys recent progress on issues related to the Bartnik quasi-local mass $m_B$. In addition, we formulate a number of new problems and conjectures regarding foundational properties of the mass $m_B$. This work is dedicated with pleasure to Robert Bartnik in honor of his 60th birthday.