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Electromagnetic waves propagation through the ionosphere is subject to several effects including refraction, absorption, signal delay, or Faraday rotation. A ray tracer propagator that simulates these effects is an important tool for all satellite missions relying on trans-ionospheric communications and Earth observation. This study presents an update to the 1975 Jones & Stephenson IONORT's code by implementing the use of up-to-date ionospheric, atmospheric, and geomagnetic models (IRI or NeQuick, NRLMSISE-00, IGRF), and a new 3-D model for equatorial plasma bubbles (EPBs). The developed code is part of the Ionosphere Modular Software Package (IMSP) in the context of the European Space Agency (ESA) project SIMIONO. HF radar sounders, Synthetic Aperture Radars (SAR), and GNSS Reflectometry (GNSS-R) missions constitute the main application of this software. The ray tracer has been validated with respect to the original software and by comparing real vs. simulated vertical ionograms in different locations and dates., This work was supported in part by the grant GENESIS PID2021-126436OB-C21 from the Programa Estatal para Impulsar la Investigación Científico-Técnica y su Transferencia, del Plan Estatal de Investigación Científica, Técnica y de Innovación 2021-2023 (Spain) and in part by the European Social Fund (ESF), Grant RYC-2016-2018 financed by MCIN/AEI /10.13039/501100011033., Peer Reviewed, Postprint (published version)

Teaching outdoors is an obligatory part of physical education (PE) in most countries; therefore, PE holds great potential to contribute to learning about nature, the environment and environmental sustainability (ES). This paper reports the investigation of whether Swedish PE teachers perceive ES as part of their subject, and if so, how do they implement it? Drawing on 60 PE teachers' answers to five opened questions (53 written answers and 7 oral interviews), and using British sociologist Basil Bernstein's concepts of classification and codes, this study have asked the following research questions: 1. What influences the position and legitimisation of ES in PE? 2. How does the subject culture of Swedish PE influence the introduction of ES? The result from the study shows a complexity regarding the strength of the boundaries that surround ES in PE and what this complexity might offer in terms of enablers and constraints. The result also displays a strong connection between outdoor education and its potential for teaching ES. Various options are discussed with regard to where (in what content areas in PE) and how to implement ES.

The construction of self-dual codes with large minimum distances has been an active topic in coding theory. The construction and classification of extremal self-dual codes over small fields are related to other fields of mathematics, such as lattices and invariant theory as well as combinatorial t-designs. It is well-known that q-ary self-dual cyclic codes exist only when q is an even prime power and q-ary self-dual negacyclic codes exist for any odd prime power q. In 2009 a family of binary self-dual cyclic codes with lengths ni and minimum distances di ≥ 1/2√ni, where ni goes to the infinity if i goes to the infinity, was constructed. In this paper, we construct several families of q-ary self-dual negacyclic codes of lengths n with their minimum distances larger than or equal to n1/2 for various lengths n and any given odd prime power q. When q ∈ {3, 5} and the length is small, the minimum distances of the constructed self-dual negacyclic codes are comparable with these self-dual codes with largest known minimum distances in the literature. IEEE

Data augmentation algorithms, such as back translation, have shown to be effective in various deep-learning tasks. Despite their remarkable success, there has been a hurdle to applying data augmentation algorithms to code-related tasks since code consists of discrete tokens with uniqueness and certainty. In this work, we propose FeaMix, a novel yet simple data augmentation approach designed for the feature mix with memory batch based on self-consistency learning. FeaMix has a couple of uniqueness. First, it specially selects the samples to be mixed by memory batch to guarantee that the generated features are in the same spatial distribution as the mixed features. Second, it extends the self-consistency learning technique to optimize the language model for code-related tasks. With extensive experiments, we empirically validate that our method outperforms several baseline models and traditional data augmentation methods on code generation and code translation. It is noteworthy that we achieve state-of-the-art results in the CoNaLa and CodeTrans benchmarks, with a significant improvement of 1.9% in the Exact Match accuracy metric for code translation tasks. IEEE

Geometry- and appearance-controlled full-body human image generation is an interesting but challenging task. Existing solutions are either unconditional or dependent on coarse conditions (e.g., pose, text), thus lacking explicit geometry and appearance control of body and garment. Sketching offers such editing ability and has been adopted in various sketch-based face generation and editing solutions. However, directly adapting sketch-based face generation to full-body generation often fails to produce high-fidelity and diverse results due to the high complexity and diversity in the pose, body shape, and garment shape and texture. Recent geometrically controllable diffusion-based methods mainly rely on prompts to generate appearance. It is hard to balance the realism and the faithfulness of their results to the sketch when the input is coarse. This work presents Sketch2Human, the first system for controllable full-body human image generation guided by a semantic sketch (for geometry control) and a reference image (for appearance control). Our solution is based on the latent space of StyleGAN-Human with inverted geometry and appearance latent codes as input. Specifically, we present a sketch encoder trained with a large synthetic dataset sampled from StyleGAN-Human's latent space and directly supervised by sketches rather than real images. Considering the entangled information of partial geometry and texture in StyleGAN-Human and the absence of disentangled datasets, we design a novel training scheme that creates geometry-preserved and appearance-transferred training data to tune a generator to achieve disentangled geometry and appearance control. Although our method is trained with synthetic data, it can also handle hand-drawn sketches. Qualitative and quantitative evaluations demonstrate the superior performance of our method to state-of-the-art methods. IEEE

The engineering of complex software systems is often the result of a highly collaborative effort. However, collaboration within a multinational enterprise has an overlooked legal implication when developers collaborate across national borders: It is taxable. In this article, we discuss the unsolved problem of taxing collaborative software engineering across borders.

This paper presents SOBO, a bot we designed to automatically provide feedback on code quality to undergraduate students. SOBO has been deployed in a course at the KTH Royal Institute of Technology in Sweden with more than 130 students., QC 20240701

Power-electronic-based grid emulators are emerging as a promising way to test the grid-code compliance of renewable energy resources. Yet, the ever-increasing power and voltage levels of device under test (DUT) pose new requirements and challenges to power-electronic-based grid emulators. This article first gives an overview of testing capability requirements based on the recent grid codes and standards and then discusses the resulted dynamic interactions and solutions for power-electronic-based grid emulators. Perspectives on the open issues and emerging trends of grid emulators are finally shared., QC 20240626

Cross-modal hashing plays a pivotal role in large-scale remote sensing (RS) ship image retrieval. RS ship images often exhibit similar overall appearance with subtle differences. Existing hashing methods typically employ feature non-interaction strategies to generate common hash codes, which may not effectively capture the correlations between cross-modal ship images to reduce intermodality discrepancies. To address this issue, we propose a novel cross-modal hashing approach based on feature semi-interaction and semantic ranking (FSISR) for RS ship image retrieval. Our FSISR approach not only captures intricate correlations between different ship image modalities, but also enables the construction of hash tables for large-scale retrieval. FSISR comprises a feature semi-interaction module and a semantic ranking objective function. The semi-interaction module utilizes clustering centers from one modality to learn the correlations between two modalities and generate robust shared representations. The objective function optimizes these representations in a common Hamming space, consisting of a shared semantic alignment loss and a margin-free ranking loss. The alignment loss employs a shared semantic layer to preserve label-level similarity, while the ranking loss incorporates hard examples to establish a margin-free loss that captures similarity ranking relationships. We evaluate the performance of our method on benchmark datasets and demonstrate its effectiveness for cross-modal RS ship image retrieval. https://github.com/sunyuxi/FSISR., QC 20240408

Multiple brain imaging modalities can provide complementary pathologic information for clinical diagnosis. However, it is huge challenge to acquire enough modalities in clinical practice. In this work, a cross-modality reconstruction model, called fine-grain aware generative adversarial network (FA-GAN), is proposed to reconstruct the target modality images of brain from the 2D source modality images with a dual-stages manner. The FA-GAN is able to mine the multi-level shared latent representations from the source modality images and then reconstruct the target modality image from coarse to fine progressively. Specifically, in the coarse stage, the Multi-Grain Extractor firstly extracts and disentangles the shared latent features from the source modality images, and synthesizes the coarse target modality images with a pyramidal network. The Feature-Joint Encoder then encodes the latent features and frequency features jointly. In the fine stage, the Fine-Texture Generator is fed with the joint codes to fine tune the reconstruction of the fine-grained target modality. The wavelet transformation module is employed to extract the frequency codes and guide the Fine-Texture Generator to synthesize finer textures. Comprehensive experiments from MR to PET images on ADNI datasets demonstrate that the proposed model achieves finer structure recovery and outperforms the competing methods quantitatively and qualitatively.

The notion of polyglot software development refers to the fact that most software projects nowadays rely on multiple languages to deal with widely different concerns, from core business concerns to user interface, security, and deployment concerns among many others. Many different wordings around this notion have been proposed in the literature, with little understanding of their differences. In this article, we propose a concise and unambiguous definition of polyglot software development including a conceptual model and its illustration on a well-known, open-source project. We further characterize the techniques used for the specification and operationalization of polyglot software development with a feature model, concentrating on polyglot programming. We conclude the article outlining the many challenges and perspectives raised by polyglot software development.

Constacyclic codes contain cyclic codes as a subclass and have nice algebraic structures. Constacyclic codes have theoretical importance, as they are connected to a number of areas of mathematics and outperform cyclic codes in several aspects. Negacyclic codes are a subclass of constacyclic codes and are distance-optimal in many cases. However, compared with the extensive study of cyclic codes, negacyclic codes are much less studied. In this paper, several families of ternary negacyclic codes and their duals are constructed and analysed. These families of negacyclic codes and their duals contain distance-optimal codes and have very good parameters in general. The duals of three families of ternary negacyclic codes presented in this paper are distance-optimal. IEEE

The concept of anagrams as a form of cryptic communication has not gained much currency of usage in our contemporary world, particularly in the global South. Apart from its usage as a pastime in leisure and entertainment activities in games and puzzles, its usage has not transcended these pedantic forms and formats into more professional communicative utilities. This study is interested in investigating the communicative forms and formats inherent in the use of anagrams, especially in cryptic communication. It also hopes to emphasise the historical use of such cryptic systems as anagrams, secret codes, and underground symbolic and literary forms of communication, deliberate misinformation, disinformation and propaganda in our contemporary world. The study is nestled within the “Diffusion of Innovations theory” of mass media, which traces how people adopt a new idea or practice based on the available information. The study avers that much utility is inherent in the adoption of a cryptic communication system that can be derived from anagrams and other forms and systems of discreet, secret or crypto-communication, both for deific, ritualistic, medical, psycho-therapeutic, civilian and militaristic uses.

Constacyclic codes over finite fields are a family of linear codes and contain cyclic codes as a subclass. Constacyclic codes are related to many areas of mathematics and outperform cyclic codes in several aspects. Hence, constacyclic codes are of theoretical importance. On the other hand, constacyclic codes are important in practice, as they have rich algebraic structures and may have efficient decoding algorithms. In this paper, two classes of constacyclic codes are constructed using a general construction of constacyclic codes with cyclic codes. The first class of constacyclic codes is motivated by the punctured Dilix cyclic codes and the second class is motivated by the punctured generalised Reed-Muller codes. The two classes of constacyclic codes contain optimal linear codes. The parameters of the two classes of constacyclic codes are analysed and some open problems are presented in this paper. IEEE

Binary cyclic codes with parameters [n, (n + 1)/2, d ≥ √n] are very interesting, as their minimum distances have a square-root bound. The binary quadratic residue codes and the punctured binary Reed-Muller codes of order (m-1)/2 for odd m are two infinite families of binary cyclic codes with such parameters. The objective of this paper is to present and analyse an infinite family of binary BCH codes C(m) with parameters [2m -1, 2m-1, d] whose minimum distance d much exceeds the square-root bound when m ≥ 11 is a prime. The binary BCH code C(3) is the binary Hamming code and distance-optimal. The binary BCH code C(5) has parameters [31, 16, 7] and is distance-almost-optimal. The binary BCH code C(7) has parameters [127, 64, 21] and has the best known parameters. In addition, there is no known [2m - 1, 2m-1] binary cyclic code whose minimum distance is better than the minimum distance of this binary BCH code C(m) with parameters 2m - 1, 2m-1] for any odd prime m. IEEE

Cyclic codes are important in theory, as they are closely related to a number of areas of mathematics. Cyclic codes are also important in practice, as they have efficient encoding and decoding algorithms. An infinite family of cyclic codes over GF(q) is said to have linearly-best-known parameters if for any [n,k,d] code C in this family, there is no known [n, k, d′] linear code over GF(q) such that d′ > d. An infinite family of cyclic codes over GF(q) is said to have cyclicly-best-known parameters if for any [n, k, d] code C in this family, there is no known [n, k, d′] cyclic code over GF(q) such that d′ > d. It is very rare to see an infinite family of binary cyclic codes with cyclicly-best-known parameters whose duals codes have also cyclicly-best-known parameters. The objective of this paper is to study such family of binary cyclic codes of length 2m – 1 and dimension 2m – 1 – m(m – 1)/2, denoted by C (2,m,2), and their dual codes C⊥ (2,m,2). The weight distribution of C⊥ (2,m,2) is settled and the parameters of C(2,m,2) are investigated in this paper. A larger family of binary cyclic codes C(2,m,r) and their duals are also constructed and studied in this paper, where 0 ≤ r ≤ m – 1. IEEE

One of the most common channel errors in molecular communication systems is a single adjacent transposition (SAT) error. It happens both due to molecular noise and due to the diffusive movement of molecules when some of them reach the receiver faster than others. In this paper, we propose a simple solution to this problem based on integer codes that can correct SAT errors. The proposed codes are less complex and more rate-efficient than existing codes of similar properties. In addition, the proposed codes use integer and lookup table operations, which makes them suitable for implementation on nano-controllers that will be embedded in future nano-implants.

In recent years, query-based static application security testing (Q-SAST) tools such as CodeQL have gained popularity due to their ability to codify vulnerability knowledge into SQL-like queries and search for vulnerabilities in the database derived from the software. The industry has made considerable progress in building Q-SAST tools, facilitating their integration into the continuous integration (CI) pipeline, and sustaining an active community. However, we do not have a systematic understanding of their vulnerability detection capability in comparison to conventional SAST tools. We conduct the first in-depth study of Q-SAST to demystify their C/C++ vulnerability detectability. Our study is conducted from three complementary aspects. We first use a synthetic CWE test suite and a real-world CVE test suite, totaling almost 30K programs with known CWE/CVE, to assess popular (commercial) Q-SAST and industry-leading SAST (requiring no queries). Then, we gather defect-fixing pull requests (PRs) since the release dates of three popular Q-SAST tools, characterizing historically-fixed defects and comparing them to pitfalls exposed in our CWE/CVE study. To enhance vulnerability detection, we design SAST-MT, a metamorphic testing framework to detect false positives (FPs) and false negatives (FNs) of Q-SAST. Findings of SAST-MT can be used to easily expose the root causes of Q-SAST's FPs and FNs. We summarize lessons from our study that can benefit both users and developers of Q-SAST. IEEE

We show that for a wide range of channels and code ensembles with pairwise-independent codewords, with probability tending to 1 with the code length, expurgating an arbitrarily small fraction of codewords from a randomly selected code results in a code attaining the expurgated exponent., This work was supported in part by the Ramon y Cajal fellowship program (grant RYC2021-033908-I) funded by the Spanish Government and the European Union “NextGenerationEU” Recovery Plan, the European Research Council under ERC Agreement 725411 and by the Spanish Ministry of Economy and Competitiveness under Grant PID2020-116683GB-C22., Peer Reviewed, Postprint (published version)

Twenty years ago, in 2003, a European project was started to increase the sustainability of existing railway bridges. This paper summarises what was achieved and looks ahead. Nine Working Packages were organized: (1) Background material; (2) Guidance by stakeholders; (3) Condition Assessment and Inspection Guidelines; (4) Loads, Capacity and Resistance Guidelines; (5) Monitoring Guidelines; (6) Repair and Strengthening Guidelines; (7) Demonstration with Field testing of Bridges; (8) Demonstration on Monitoring on Bridges; and (9) Training and Dissemination. Some of the main results (from 4 Guidelines and 47 Background documents) are highlighted and some experiences, conclusions and thoughts about the future are given. Hidden strengths and weaknesses are discussed, analyses and codes for assessment can be improved, new monitoring and strengthening methods are available and life length can be prolonged., ISBN for host publication: 978-3-85748-200-7, Sustainable Bridges

Editor ’s notes: The author in this article advocates for Processing in NoC (PiN) as a means to actively engage a Network-on-Chip (NoC) in computation. The article highlights the benefits of utilizing the communication network for system-level performance enhancement, with a case study demonstrating its advantages over conventional passive NoC approaches. —Mahdi Nikdast, Colorado State University, USA —Miquel Moreto, Barcelona Supercomputing Center, Spain —Masoumeh (Azin) Ebrahimi, KTH Royal Institute of Technology, Sweden —Sujay Deb, IIIT Delhi, India, QC 20231211

Programming education should aim to provide students with a broad range of skills that they will later use while developing software. An important aspect in this is their ability to write code that is not only correct but also of high quality. Unfortunately, this is difficult to control in the setting of a massive open online course. In this paper, we carry out an analysis of the code quality of submissions from JetBrains Academy — a platform for studying programming in an industry-like project-based setting with an embedded code quality assessment tool called Hyperstyle. We analyzed more than a million Java submissions and more than 1.3 million Python submissions, studied the most prevalent types of code quality issues and the dynamics of how students fix them. We provide several case studies of different issues, as well as an analysis of why certain issues remain unfixed even after several attempts. Also, we studied abnormally long sequences of submissions, in which students attempted to fix code quality issues after passing the task. Our results point the way towards the improvement of online courses, such as making sure that the task itself does not incentivize students to write code poorly.

This article discusses open source software supply chain attacks and proposes a general taxonomy describing how attackers conduct them. We then provide a list of safeguards to mitigate such attacks. We present our tool "Risk Explorer for Software Supply Chains" to explore such information, and we discuss its industrial use-cases., Peer Reviewed, Postprint (author's final draft)

The development of deep generative models has inspired various facial image editing methods, but many of them are difficult to be directly applied to video editing due to various challenges ranging from imposing 3D constraints, preserving identity consistency, ensuring temporal coherence, etc. To address these challenges, we propose a new framework operating on the StyleGAN2 latent space for identity-aware and shape-aware edit propagation on face videos. In order to reduce the difficulties of maintaining the identity, keeping the original 3D motion, and avoiding shape distortions, we disentangle the StyleGAN2 latent vectors of human face video frames to decouple the appearance, shape, expression, and motion from identity. An edit encoding module is used to map a sequence of image frames to continuous latent codes with 3D parametric control and is trained in a self-supervised manner with identity loss and triple shape losses. Our model supports propagation of edits in various forms: I. direct appearance editing on a specific keyframe, II. implicit editing of face shape via a given reference image, and III. existing latent-based semantic edits. Experiments show that our method works well for various forms of videos in the wild and outperforms an animation-based approach and the recent deep generative techniques.

Securing IoT devices is gaining attention as the security risks associated with these devices increase rapidly. TrustZone-M, a Trusted Execution Environment (TEE) for Cortex-M processors, ensures stronger security within an IoT device by allowing isolated execution of security-critical operations, without trusting the entire software stack. However, TrustZone-M does not guarantee secure cross-world communication between applications in the Normal and Secure worlds. The cryptographic protection of the communication channel is an obvious solution; however, within a low-power IoT device, it incurs high overhead if applied to each cross-world message exchange. We present ShieLD, a framework that enables a secure communication channel between the two TrustZone-M worlds by leveraging the Memory Protection Unit (MPU). ShieLD guarantees confidentiality, integrity and authentication services without requiring any cryptographic operations. We implement and evaluate ShieLD using a Musca-A test chip board with Cortex-M33 that supports TrustZone-M. Our empirical evaluation shows, among other gains, the cross-zone communication protected with ShieLD is 5 times faster than the conventional crypto-based communication.

A finite classical polar space of rank \(n\) consists of the totally isotropic subspaces of a finite vector space equipped with a nondegenerate form such that \(n\) is the maximal dimension of such a subspace. A \(t\)-Steiner system in a finite classical polar space of rank \(n\) is a collection \(Y\) of totally isotropic \(n\)-spaces such that each totally isotropic \(t\)-space is contained in exactly one member of \(Y\). Nontrivial examples are known only for \(t=1\) and \(t=n-1\). We give an almost complete classification of such \(t\)-Steiner systems, showing that such objects can only exist in some corner cases. This classification result arises from a more general result on packings in polar spaces.Mathematics Subject Classifications: 51E23, 05E30, 33C80Keywords: Association schemes, codes, polar spaces, Steiner systems

Co-simulation is a key step in the development of today’s complex cyber-physical systems (CPS), specially in the integration and validation activities. However, performing a co-simulation involving models developed in different environments and possibly deployed in different platforms with mixed real-time and non real-time constraints is a challenging engineering task. A promising technology that could help overcome communication and synchronisation difficulties is the non-proprietary standard Distributed Co-simulation Protocol (DCP). This standard defines an application-level communication protocol, independent of the platform and the communication medium, that regulates the exchange of information between the co-simulation entities. This paper presents a co-simulation interface based on the DCP standard. It offers a novel approach to apply the DCP standard. Instead of using it as a model encapsulation mechanism, having to develop an specific DCP slave for each application, it is proposed to use it as a generic co-simulation interface. To this end, a Simulink library has been developed, allowing to connect models developed in Simulink with the outside world in an standardised way. Moreover, by exploiting the code generation potential of Simulink, a wide variety of devices become accessible, thus enabling x-in-the-loop simulations, which are commonly used tests in the verification and validation process of CPSs. This library has been tested in a soft real-time co-simulation application between a Simulink instance and an application running on a Xilinx Zynq Ultrascale+ System-on-Chip. As an additional contribution, an analysis of DCP synchronisation problems when simulating closed-loop systems composed of two slaves is performed. Finding that the main causes are the occurrence of random delays and that the simulations of the two slaves start at an arbitrary time. A possible solution to this problem is also presented.

In this paper, we address the problem of automatic repair of software vulnerabilities with deep learning. The major problem with data-driven vulnerability repair is that the few existing datasets of known confirmed vulnerabilities consist of only a few thousand examples. However, training a deep learning model often requires hundreds of thousands of examples. In this work, we leverage the intuition that the bug fixing task and the vulnerability fixing task are related and that the knowledge learned from bug fixes can be transferred to fixing vulnerabilities. In the machine learning community, this technique is called transfer learning. In this paper, we propose an approach for repairing security vulnerabilities named VRepair which is based on transfer learning. VRepair is first trained on a large bug fix corpus and is then tuned on a vulnerability fix dataset, which is an order of magnitude smaller. In our experiments, we show that a model trained only on a bug fix corpus can already fix some vulnerabilities. Then, we demonstrate that transfer learning improves the ability to repair vulnerable C functions. We also show that the transfer learning model performs better than a model trained with a denoising task and fine-tuned on the vulnerability fixing task. To sum up, this paper shows that transfer learning works well for repairing security vulnerabilities in C compared to learning on a small dataset., QC 20231117

Recently, the proliferation of commercial ML-based services has given rise to new job roles, such as ML engineers. Despite being highly sought-after in the job market, ML engineers are difficult to recruit, possibly due to the lack of specialized academic curricula for this position at universities. To address this gap, in the past two years, we have supplemented traditional Computer Science and Data Science university courses with a project-based course on MLOps focused on the fundamental skills required of ML engineers. In this paper, we present an overview of the course by showcasing a couple of sample projects developed by our students. Additionally, we share the lessons learned from offering the course at two different institutions., This work is partially supported by the NRRP Initiative – Next Generation EU ("FAIR - Future Artificial Intelligence Research", code PE00000013, CUP H97G22000210007); the Complementary National Plan PNC-I.1 ("DARE - DigitAl lifelong pRevEntion initiative", code PNC0000002, CUP B53C22006420001), and the project TED2021- 130923B-I00, funded by MCIN/AEI/10.13039/50110001 1033 and the European Union Next Generation EU/PRTR., Peer Reviewed, Postprint (author's final draft)

© 2009 Optical Society of America. This work has been supported by Center for Innovation in Transport (CENIT) project “Tecnologías avanzadas para los equipos y procesos de fabricación de 2015: e-eficiente, e-cológica, e-máquina (eEe)” of the Ministerio de Industria, Turismo y Comercio of Spain and by the Madrid Autonomous Community-University of Alcalá de Henares (CAM-UAH) project CCG08-UAH/TIC-3941., Two-grating measurement systems are routinely employed for high-resolution measurements of angular and linear displacement. Usually, these systems incorporate zero reference codes (ZRCs) to obtain a zero reference signal (ZRS), which is used as a stage-homing signal. This signal provides absolute information of the position to the otherwise relative information provided by the two-grating incremental subsystems. A zero reference signal is commonly obtained illuminating the superposition of two identical pseudorandom codes and registering the transmitted light by means of a photodiode. To increase the resolution of the system, a reduction of the grating period and the ZRC widths is required. Due to this reduction, the diffractive effects produce a widening of the ZRS and, in turn, a loss of the measuring accuracy. In this work, we propose a method to narrow the distorted signal obtained with a Lau-based encoder, reinstating the accuracy of the ZRS. The method consists of the inclusion of a correlation mask on the detector. A theoretical model to design the mask has been developed, and experimental results have been obtained that validate the proposed technique., Centro de Innovación del Transporte (CENIT), España, Ministerio de Industria, Turismo y Comercio, España, Comunidad Autónoma de Madrid (CAM), Universidad Autónoma de Madrid (UAM), Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

Several software tools are available in the literature for the design and embedded implementation of linear model predictive control (MPC), both in its implicit and explicit (either exact or approximate) forms. Most of them generate C code for easy implementation on a microcontroller, and the others can convert the C code into hardware description language code for implementation on a field programmable gate array (FPGA). However, a unified tool allowing one to generate efficient embedded MPC for an FPGA, starting from the definition of the plant and its constraints, was still missing. The MOBY-DIC2 toolbox described in this brief bridges this gap. To illustrate its functionalities, the tool is exploited to embed the controller and observer for a real buck power converter in an FPGA. This implementation achieves a latency of about 30 $\mu $ s with the implicit controller and 240 ns with the approximate explicit controller.

We consider the problem of error control in a coded, multicast network, focusing on the scenario where the errors can occur only on a proper subset of the network edges. We model this problem via an adversarial noise, presenting a formal framework and a series of techniques to obtain upper and lower bounds on the network’s (1-shot) capacity, improving on the best currently known results. In particular, we show that traditional cut-set bounds are not tight in general in the presence of a restricted adversary, and that the non-tightness of these is caused precisely by the restrictions imposed on the noise (and not, as one may expect, by the alphabet size). We also show that, in sharp contrast with the typical situation within network coding, capacity cannot be achieved in general by combining linear network coding with end-to-end channel coding, not even when the underlying network has a single source and a single terminal. We finally illustrate how network decoding techniques are necessary to achieve capacity in the scenarios we examine, exhibiting capacity-achieving schemes and lower bounds for various classes of networks.

Over the past decade, significant progress in quantum technologies has been made, and hence, engineering of these systems has become an important research area. Many researchers have become interested in studying ways in which classical integrated circuits can be used to complement quantum mechanical systems, enabling more compact, performant, and/or extensible systems than would be otherwise feasible. In this article - written by a consortium of early contributors to the field - we provide a review of some of the early integrated circuits for the quantum information sciences. Complementary metal - oxide semiconductor (CMOS) and bipolar CMOS (BiCMOS) integrated circuits for nuclear magnetic resonance, nitrogen-vacancy-based magnetometry, trapped-ion-based quantum computing, superconductor-based quantum computing, and quantum-dot-based quantum computing are described. In each case, the basic technological requirements are presented before describing proof-of-concept integrated circuits. We conclude by summarizing some of the many open research areas in the quantum information sciences for CMOS designers., Electronics, Quantum Circuit Architectures and Technology

OpenMP is the de-facto standard for shared memory systems in High-Performance Computing (HPC). It includes a tasking model that offers a high-level of abstraction to effectively exploit structured (loop-based) and highly dynamic unstructured (task-based) parallelism in an easy and flexible way. Unfortunately, the run-time overheads introduced to manage tasks are (very) high in most common OpenMP frameworks (e.g., GCC, LLVM), which defeats the potential benefits of the tasking model, and makes it suitable for coarse-grained tasks only. This paper presents taskgraph , a framework that uses a task dependency graph (TDG) to represent a region of code implemented with OpenMP tasks in order to reduce the run-time overheads associated with the management of tasks, i.e., contention and parallel orchestration, including task creation and synchronization. The TDG avoids the overheads related to the resolution of task dependencies and greatly reduces those deriving from accesses to shared resources. Moreover, the taskgraph framework introduces in OpenMP the record-and-replay execution model that accelerates the taskgraph region from its second execution. Overall, the multiple optimizations presented in this paper allow exploiting fine-grained OpenMP tasks to cope with the trend in current applications pointing to leverage massive on-node parallelism, fine-grained and dynamic scheduling paradigms. The framework is implemented on LLVM 15.0. Results show that the taskgraph implementation outperforms the vanilla OpenMP system in terms of performance and scalability, for all structured and unstructured parallelism, and considering coarse and fine grained tasks. Furthermore, the proposed framework makes the tasking model a competitive alternative to the OpenMP thread model in most cases., This work was supported in part by the Generalitat de Catalunya project RESPECT under Grant 2021 PROD 00179 and in part by the EU H2020 project AMPERE under Grant 871669, Peer Reviewed, Postprint (author's final draft)

We present and analyze a new construction of bipolar balanced codes where each codeword contains equally many -1's and +1's. The new code is minimally modified as the number of symbol changes made to the source word for translating it into a balanced codeword is as small as possible. The balanced codes feature low redundancy and time complexity. Large look-up tables are avoided., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Discrete Mathematics and Optimization

One of the Round 3 Finalists in the NIST post-quantum cryptography call is the Classic McEliece cryptosystem. Although it is one of the most secure cryptosystems, the large size of its public key remains a practical limitation. In this work, we propose a McEliece-type cryptosystem using large minimum distance error-correcting codes derived from self-dual codes. To the best of our knowledge, such codes have not been implemented in a code-based cryptosystem until now. Moreover, we modify the decryption step of the system by introducing a decryption algorithm based on two private keys. We determine the parameters of binary codes with large minimum distance, which, if implemented into a McEliece-type cryptosystem, would provide a security level respectively of 80, 128, and 256 bits. For the 80-bit security case, we construct a large minimum distance self-dual code of length 1064, and use it to derive a random punctured code to be used in the corresponding McEliece-type cryptosystem. Compared to the original McEliece cryptosystem, the key size is reduced by about 38.5%, although an optimal decoding set is yet to be constructed to make the new system fully defined and usable., Cyber Security

This letter addresses the problem of remote state estimation subject to packet dropouts, focusing on the use of an event-triggered sensor scheduler to conserve communication resources. However, packet dropouts introduce significant challenges, as the remote estimator cannot distinguish between packet loss caused by poor channel conditions and the event trigger. To overcome this issue, we propose a novel formulation that incorporates error-detecting codes. We prove that the Gaussian property of the system state, commonly utilized in the literature, does not hold in this scenario. Instead, the system state follows an extended Gaussian mixture model (GMM). We present an exact minimum mean-squared error (MMSE) estimator and an approximate estimator, which significantly reduces algorithm complexity without sacrificing performance. Our simulation results show that the approximate estimator achieves nearly the same performance as the exact estimator while requiring much less computation time. Moreover, the proposed event trigger outperforms existing schedulers in terms of estimation accuracy.

The hardware description of circuits usually contains many loops. Register Transfer Level (RTL) simulation is a critical step to verify the correctness of circuits and is time-consuming. Thus, it is necessary to speed up its process. However, the speedup of existing RTL simulation acceleration techniques is usually small. Although the speedup of hardware acceleration is large, the hardware cost is high. Some methods utilize performance models without performing RTL simulation to obtain rough simulation performance and have large speedup. However, they do not support functional verification. In order to address the problems, we propose a loop-oriented RTL simulation acceleration approach based on code instrumentation for designs synthesized by High-Level Synthesis. Our approach reduces the RTL simulation time by skipping a large number of repeated loop iterations, and maintains high accuracy for the prediction of the number of cycles by reserving some loop iterations. We establish a performance prediction model and an interval value formula for skipping loop iterations. We conduct experiments on the MachSuite benchmark. The results show that for the RTL simulation of single data processing and batch data processing, the average speedup of our approach can reach 7.49× and 43.3×, respectively, and the average prediction errors of the number of cycles are 1.71% and 1.06%, respectively. It also reveals that the interval value obtained by our approach for skipping loop iterations can quickly and effectively balance between the accuracy of prediction of the number of cycles and speedup. Compared to the state-of-the-art approach ESSENT, the speedup of our approach is better and the accuracy of prediction of the number of cycles remains at the same level as that of performance models.

Low-density lattice codes (LDLCs) achieve near-capacity performance on additive white Gaussian noise (AWGN) channels. The M-Gaussian decoder is the state-of-the-art message passing decoder for LDLCs in terms of the error performance. However, this decoder has complexity O(Md-1) with messages represented by Gaussian mixtures, where d is the degree of an LDLC and M is the number of Gaussian functions for approximating each check node message. In this paper, we establish the correspondence between Gaussian functions for approximating a variable node message and points of a certain lattice. Based on this lattice viewpoint, the problem of approximating a variable node message is formulated as a lattice point enumeration (LPE) problem. Then, an LPE decoder with linear complexity O(d) is proposed. Our simulation results validate that the LPE decoder achieves almost the same error performance as the M-Gaussian decoder.

We introduce the class of rank-metric geometric lattices and initiate the study of their structural properties. Rank-metric lattices can be seen as the q-analogues of higher-weight Dowling lattices, defined by Dowling himself in 1971. We fully characterize the supersolvable rank-metric lattices and compute their characteristic polynomials. We then concentrate on small rank-metric lattices whose characteristic polynomial we cannot compute, and provide a formula for them under a polyno-miality assumption on their Whitney numbers of the first kind. The proof relies on computational results and on the theory of vector rank-metric codes, which we review in this paper from the perspective of rank-metric lattices. More precisely, we introduce the notion of lattice-rank weights of a rank-metric code and inves-tigate their properties as combinatorial invariants and as code distinguishers for inequivalent codes.Mathematics Subject Classifications: 05A15, 06C10, 94B99

Secure processors with hardware-enforced isolation are crucial for secure cloud computation. However, commercial secure processors have underestimated the capabilities of attackers and failed to provide secure execution environments capable of protecting sensitive information against side-channel attacks. Remote Attestation protocols based on traditional signature schemes are not secure under side-channel attacks anymore since their secret keys can be leaked. Previously, Key-Insulated Schemes (KIS) have been introduced to mitigate the damage caused by secret key exposure in cryptosystems by breaking the lifetime of secret keys into independent sessions. KIS protect the security of all other sessions if any session keys are compromised, however, provide no security guarantees for a compromised session. We introduce a new cryptographic primitive called One-Time Signature with Secret Key Exposure (OTS-SKE), which ensures no one can forge a valid signature of a new message or nonce even if all secret session keys are leaked. OTS-SKE enables us to sign attestation reports securely under a powerful adversary who can observe all digital states in secure enclaves through side-channel attacks. We also minimize the trusted computing base by introducing a secure co-processor that is only responsible for key generation into the system. Our experiments show that the signing of OTS-SKE is faster than KIS as well as Elliptic Curve Digital Signature Algorithm (ECDSA) used in Intel SGX.

In this article we revisit smoothing bounds in parallel between lattices and codes. Initially introduced by Micciancio and Regev, these bounds were instantiated with Gaussian distributions and were crucial for arguing the security of many lattice-based cryptosystems. Unencumbered by direct application concerns, we provide a systematic study of how these bounds are obtained for both lattices and codes, transferring techniques between both areas. We also consider multiple choices of spherically symmetric noise distributions. We found that the best strategy for a worst-case bound combines Parseval’s Identity, the Cauchy-Schwarz inequality, and the second linear programming bound, and this holds for both codes and lattices and all noise distributions at hand. For an average-case analysis, the linear programming bound can be replaced by an expected value computation. This alone gives optimal results for spherically uniform noise over random codes and random lattices. This also improves prior Gaussian smoothing bounds for worst-case lattices, but surprisingly this provides even better results with uniform ball noise than for Gaussian (or Bernoulli noise for codes). This counterintuitive situation can be resolved by adequate decomposition and truncation of Gaussian and Bernoulli distributions into a superposition of uniform noise, giving further improvement for those cases, and putting them on par with the uniform cases.

We study two problems of private matrix multiplication, over a distributed computing system consisting of a master node, and multiple servers that collectively store a family of public matrices using Maximum-Distance-Separable (MDS) codes. In the first problem of Private and Secure Matrix Multiplication (PSMM) from colluding servers, the master intends to compute the product of its confidential matrix $\textbackslash{}mathbf {A}$ with a target matrix stored on the servers, without revealing any information about $\textbackslash{}mathbf {A}$ and the index of target matrix to some colluding servers. In the second problem of Fully Private Matrix Multiplication (FPMM) from colluding servers, the matrix $\textbackslash{}mathbf {A}$ is also selected from another family of public matrices stored at the servers in MDS form. In this case, the indices of the two target matrices should both be kept private from colluding servers. We develop novel strategies for the two PSMM and FPMM problems, which simultaneously guarantee information-theoretic data/index privacy and computation correctness. We compare the proposed PSMM strategy with a previous PSMM strategy with a weaker privacy guarantee (non-colluding servers), and demonstrate substantial improvements over the previous strategy in terms of communication and computation overheads. Moreover, compared with a baseline FPMM strategy that uses the idea of Private Information Retrieval (PIR) to directly retrieve the desired matrix multiplication, the proposed FPMM strategy significantly reduces storage overhead, but slightly incurs large communication and computation overheads.

In order to schedule resources efficiently or maintain applications' continuity for mobile customers, edge platforms often need to adaptively migrate the applications on them. However, our measurement shows that existing migration solutions cannot solve the issue of migrating video analytics applications in edge computing because the memory states of video analytics applications have different characteristics from other applications. We conduct a breakdown analysis of the memory states of video analytics applications, and propose to treat three types of states separately with three different techniques, i.e. , warm-up, sync, and replay, to minimize the negative influence of migrations on application performance. Based on this idea, we implement a prototype system in which two new components, i.e. , state store and sidecar , are designed to achieve near-transparent live migration with minimal application code modifications. Evaluation experiments demonstrate that the time of application interruption caused by migrating a video analytics application with our solution is less than 405ms, and our solution does not consume much resources.

Khushal Khan Khattak is a prolific writer, poet, politician, and community leader of Pashtun nation. He, as a leader, understood the spirit and soul of the Pashtuns at that time. So, his poems have all the cultural codes of the Pashtun nation. For example: Challenge, honor, masculinity, hospitality, shame, modesty, honesty, unity and love. A few hundred years ago, the cultural codes, which described in his poems, are almost still present in the Pashtun community. The main reason being the backwardness of the Pashtun nation and their society, is because the cultural codes change as society changes. The society of Pashtun nation does not chance until today. It has its old shape as two or three hundred year ago. There are a lot of codes that we can find in both, also in the poems of Khushal Khan Khatak and in the space of Pashtun nation. There are not the most of the codes in Western societies nowadays, because these codes that are often considered in Islamic countries.