Coding Problem Research Articles

Tight Exponential Strong Converse for Source Coding Problem with Encoded Side Information

Tight Exponential Strong Converse for Source Coding Problem with Encoded Side Information

On the elastic instability of a simple truss structure subjected to a tensile dead load

There are a significant number of examples of structures that fail due to elastic instability of elements subjected to compressive forces. There are also examples of elastic instability caused by tensile forces, but they are less well known. This paper presents an interesting example of the latter type, whose main feature is its counterintuitive post-critical behavior. In fact, the applied dead load does negative work in the movement from the critical to the post-critical equilibrium configuration. The example admits a complete analytical solution, which makes it ideal for teaching use and as a benchmark problem for testing computational codes.

Decoding quantum color codes with MaxSAT

In classical computing, error-correcting codes are well established and are ubiquitous both in theory and practical applications. For quantum computing, error-correction is essential as well, but harder to realize, coming along with substantial resource overheads and being concomitant with needs for substantial classical computing. Quantum error-correcting codes play a central role on the avenue towards fault-tolerant quantum computation beyond presumed near-term applications. Among those, color codes constitute a particularly important class of quantum codes that have gained interest in recent years due to favourable properties over other codes. As in classical computing, decoding is the problem of inferring an operation to restore an uncorrupted state from a corrupted one and is central in the development of fault-tolerant quantum devices. In this work, we show how the decoding problem for color codes can be reduced to a slight variation of the well-known LightsOut puzzle. We propose a novel decoder for quantum color codes using a formulation as a MaxSAT problem based on this analogy. Furthermore, we optimize the MaxSAT construction and show numerically that the decoding performance of the proposed decoder achieves state-of-the-art decoding performance on color codes. The implementation of the decoder as well as tools to automatically conduct numerical experiments are publicly available as part of the Munich Quantum Toolkit (MQT) on GitHub.

Lifted Codes with Construction of Echelon-Ferrers for Constant Dimension Codes

Finding the highest possible cardinality, Aq(n,d;k), of the set of k-dimensional subspaces in Fqn, also known as codewords, is a fundamental problem in constant dimension codes (CDCs). CDCs find applications in a number of domains, including distributed storage, cryptography, and random linear network coding. The goal of recent research papers has been to establish Aq(n,d;k). We further improved the echelon-Ferrers construction with an algorithm, and enhanced the inserting construction by swapping specified columns of the generator matrix to obtain new lower bounds.

Conditional Residual Coding: A Remedy for Bottleneck Problems in Conditional Inter Frame Coding

Conditional Residual Coding: A Remedy for Bottleneck Problems in Conditional Inter Frame Coding

Multi-Bottleneck progressive propulsion network for medical image semantic segmentation with integrated macro-micro dual-stage feature enhancement and refinement

Semantic segmentation can assist doctors to locate key lesion areas intelligently, rapidly and with high precision in medical imaging, which is of great clinical significance for the diagnosis and rehabilitation of patients in various medical fields such as oncology and neurology. Existing segmentation networks face accuracy bottlenecks because enriched information at the decoding end can’t disperse over multiple layers of semantic depth. This is compounded by challenges like complex anatomical structures and varying imaging modalities. In this study, we propose a Multi-Bottleneck Progressive Semantic Segmentation Network (MBP-SSNet), which is essentially a new Baseline based on our proposal: Multi-Bottleneck based Progressive Propulsion Feature Guidance Network (MB-PPFG Net). Its Multi-Bottleneck solves the problem of coding and decoding multiplexed transmission of enriched information, and the propulsive transmission alleviates the problem of insufficient semantic fusion. In addition, under the macro–micro processing idea, MacroFocus Pre-Bottleneck Feature Enhancer (MPBFE) is proposed at the codec intersection in order to better enhance the image contextual semantic dependency association; while MicroDetail Post- Decoding Feature Refiner (MPDFR) is proposed at the tail of the network for fine-grained polishing. In the experiment, the MBP-SSNet was compared with 17 other models across 7 datasets, including diverse medical imaging scenarios, involving metric exploration, image comparison, process validation, and statistical analysis. Concurrently, 22 types of ablation analyses were conducted on it, along with detailed discussions on two critical issues. The experimental results demonstrate that MBP-SSNet achieves an average performance improvement of 0.6809 % in medical image segmentation compared to the optimal benchmark model. The official web address of MBP-SSNet is at: https://github.com/YF-W/MBP-SSNet.

Pengaruh Kompetensi PMIK Terhadap Kinerja Petugas Rekam Medis Di Rumah Sakit Angkatan Udara Dr. Esnawan Antariksa

This research was conducted with the aim of determining the influence of PMIK (Medical Recorder and Health Information) professional competence on the performance of medical record officers at the Dr. Air Force Hospital. Esnawan Antariksa. The research method used is quantitative with inferential analysis. The data collection techniques used were observation, interviews and questionnaires. The sampling technique used a total saturated sampling technique of 14 people. Obtained from 7 PMIK competency standard indicators (Noble Professionalism, Ethics and Legal, Introspection and Personal Development, Effective Communication, Health Data and Information Management, Clinical classification skills, Disease coding and other Health Problems as well as Clinical Procedures, Health Statistics Applications, Basic Epidemiology, and Biomedicine, Management of Medical Records Services and Health Information, there are still 2 indicators in the percentage that are not good, and in the 5 performance indicators of medical record officers (Quality of Work, Quantity of Work, Supervision, Attendance, Conservation) there are still 2 indicators in the percentage not good. It was found that 3 officers had a D-III RMIK education and 11 officers still had a high school education. Based on the results of the T test, it was found that the Sig. value was 275. It could be concluded that there was no influence of PMIK competency on the performance of medical records officers.

Irreversibility analysis of Darcy-Forchheimer flow of a Williamson hybrid nanofluids near a stagnation-point across a vertical plate with buoyancy force

PurposeA novel type of heat transfer fluid known as hybrid nanofluids is used to improve the efficiency of heat exchangers. It is observed from literature evidence that hybrid nanofluids outperform single nanofluids in terms of thermal performance. This study aims to address the stagnation point flow induced by Williamson hybrid nanofluids across a vertical plate. This fluid is drenched under the influence of mixed convection in a Darcy–Forchheimer porous medium with heat source/sink and entropy generation.Design/methodology/approachBy applying the proper similarity transformation, the partial differential equations that represent the leading model of the flow problem are reduced to ordinary differential equations. For the boundary value problem of the fourth-order code (bvp4c), a built-in MATLAB finite difference code is used to tackle the flow problem and carry out the dual numerical solutions.FindingsThe shear stress decreases, but the rate of heat transfer increases because of their greater influence on the permeability parameter and Weissenberg number for both solutions. The ability of hybrid nanofluids to strengthen heat transfer with the incorporation of a porous medium is demonstrated in this study.Practical implicationsThe findings may be highly beneficial in raising the energy efficiency of thermal systems.Originality/valueThe originality of the research lies in the investigation of the Darcy–Forchheimer stagnation point flow of a Williamson hybrid nanofluid across a vertical plate, considering buoyancy forces, which introduces another layer of complexity to the flow problem. This aspect has not been extensively studied before. The results are verified and offer a very favorable balance with the acknowledged papers.

A provably masked implementation of BIKE Key Encapsulation Mechanism

BIKE is a post-quantum key encapsulation mechanism (KEM) selected for the 4th round of the NIST's standardization campaign. It relies on the hardness of the syndrome decoding problem for quasi-cyclic codes and on the indistinguishability of the public key from a random element, and provides the most competitive performance among round 4 candidates, which makes it relevant for future real-world use cases. Analyzing its side-channel resistance has been highly encouraged by the community and several works have already outlined various side-channel weaknesses and proposed ad-hoc countermeasures. However, in contrast to the well-documented research line on masking lattice-based algorithms, the possibility of generically protecting code-based algorithms by masking has only been marginally studied in a 2016 paper by Chen et al. in SAC 2015. At this stage of the standardization campaign, it is important to assess the possibility of fully masking BIKE scheme and the resulting cost in terms of performances. In this work, we provide the first high-order masked implementation of a code-based algorithm. We had to tackle many issues such as finding proper ways to handle large sparse polynomials, masking the key-generation algorithm or keeping the benefit of the bitslicing. In this paper, we present all the gadgets necessary to provide a fully masked implementation of BIKE, we discuss our different implementation choices and we propose a full proof of masking in the Ishai Sahai and Wagner (Crypto 2003) model. More practically, we also provide an open C-code masked implementation of the key-generation, encapsulation and decapsulation algorithms with extensive benchmarks. While the obtained performance is slower than existing masked lattice-based algorithms, we show that masking at order 1, 2, 3, 4 and 5 implies a performance penalty of x5.8, x14.2, x24.4, x38 and x55.6 compared to order 0 (unmasked and unoptimized BIKE). This scaling is encouraging and no Boolean to Arithmetic conversion has been used.

“Will I be replaced?” Assessing ChatGPT's effect on software development and programmer perceptions of AI tools

ChatGPT is a language model with artificial intelligence (AI) capabilities that has found utility across various sectors. Given its impact, we conducted two empirical studies to assess the potential and limitations of ChatGPT and other AI tools in software development. In the first study, we evaluated ChatGPT 3.5′s effectiveness in generating code for 180 coding problems from LeetCode, an online coding interview preparation platform. Our findings suggest that ChatGPT 3.5 is more effective in solving easy and medium coding problems but less reliable for harder problems. Further, ChatGPT 3.5 is somewhat more effective at coding problems with higher popularity scores. In the second study, we administered a questionnaire (N = 99) to programmers to gain insights into their views on ChatGPT and other AI tools. Our findings indicate that programmers use AI tools for various tasks, such as generating boilerplate code, explaining complex code, and conducting research. AI tools also help programmers to become more productive by creating better-performing, shorter, and more readable code, among other benefits. However, AI tools can sometimes misunderstand requirements and generate erroneous code. While most programmers are not currently concerned about AI tools replacing them, they are apprehensive about what the future may hold. Our research has also revealed associations between AI tool usage, trust, perceived productivity, and job security threats caused by the tools.

Equivalences among Some Information Measures for Individual Sequences and Their Applications for Fixed-Length Coding Problems

Equivalences among Some Information Measures for Individual Sequences and Their Applications for Fixed-Length Coding Problems

Saturating linear sets of minimal rank

Saturating sets are combinatorial objects in projective spaces over finite fields that have been intensively investigated in the last three decades. They are related to the so-called covering problem of codes in the Hamming metric. In this paper, we consider the recently introduced linear version of such sets, which is, in turn, related to the covering problem in the rank metric. The main questions in this context are how small the rank of a saturating linear set can be and how to construct saturating linear sets of small rank. Recently, Bonini, Borello, and Byrne provided a lower bound on the rank of saturating linear sets in a given projective space, which is shown to be tight in some cases. In this paper, we provide construction of saturating linear sets meeting the lower bound and we develop a link between the saturating property and the scatteredness of linear sets. The last part of the paper is devoted to show some parameters for which the bound is not tight.

Semantic Communication: A Survey of Its Theoretical Development.

In recent years, semantic communication has received significant attention from both academia and industry, driven by the growing demands for ultra-low latency and high-throughput capabilities in emerging intelligent services. Nonetheless, a comprehensive and effective theoretical framework for semantic communication has yet to be established. In particular, finding the fundamental limits of semantic communication, exploring the capabilities of semantic-aware networks, or utilizing theoretical guidance for deep learning in semantic communication are very important yet still unresolved issues. In general, the mathematical theory of semantic communication and the mathematical representation of semantics are referred to as semantic information theory. In this paper, we introduce the pertinent advancements in semantic information theory. Grounded in the foundational work of Claude Shannon, we present the latest developments in semantic entropy, semantic rate-distortion, and semantic channel capacity. Additionally, we analyze some open problems in semantic information measurement and semantic coding, providing a theoretical basis for the design of a semantic communication system. Furthermore, we carefully review several mathematical theories and tools and evaluate their applicability in the context of semantic communication. Finally, we shed light on the challenges encountered in both semantic communication and semantic information theory.

In search of maximum non-overlapping codes

AbstractNon-overlapping codes are block codes that have arisen in diverse contexts of computer science and biology. Applications typically require finding non-overlapping codes with large cardinalities, but the maximum size of non-overlapping codes has been determined only for cases where the codeword length divides the size of the alphabet, and for codes with codewords of length two or three. For all other alphabet sizes and codeword lengths no computationally feasible way to identify non-overlapping codes that attain the maximum size has been found to date. Herein we characterize maximal non-overlapping codes. We formulate the maximum non-overlapping code problem as an integer optimization problem and determine necessary conditions for optimality of a non-overlapping code. Moreover, we solve several instances of the optimization problem to show that the hitherto known constructions do not generate the optimal codes for many alphabet sizes and codeword lengths. We also evaluate the number of distinct maximum non-overlapping codes.

New constant dimension subspace codes from multilevel linkage construction

<p style='text-indent:20px;'>One of the main problems in subspace coding is to determine the maximal possible size of a constant dimension subspace code with given parameters. In this paper, we introduce a family of new codes, named rank-restricted Ferrers diagram rank-metric codes, to give an improved construction of constant dimension subspace codes. Our method constructs many new CDCs with larger sizes than previously best-known codes.</p>

On the rank decoding problem over finite principal ideal rings

The rank decoding problem has been the subject of much attention in this last decade. This problem, which is at the base of the security of public-key cryptosystems based on rank metric codes, is traditionally studied over finite fields. But the recent generalizations of certain classes of rank-metric codes from finite fields to finite rings have naturally created the interest to tackle the rank decoding problem in the case of finite rings.In this paper, we show that solving the rank decoding problem over finite principal ideal rings is at least as hard as the rank decoding problem over finite fields. We also show that computing the minimum rank distance for linear codes over finite principal ideal rings is equivalent to the same problem for linear codes over finite fields. Finally, we provide combinatorial type algorithms for solving the rank decoding problem over finite chain rings together with their average complexities.

Learning the sparse prior: Modern approaches

AbstractThe sparse prior has been widely adopted to establish data models for numerous applications. In this context, most of them are based on one of three foundational paradigms: the conventional sparse representation, the convolutional sparse representation, and the multi‐layer convolutional sparse representation. When the data morphology has been adequately addressed, a sparse representation can be obtained by solving the sparse coding problem specified by the data model. This article presents a comprehensive overview of these three models and their corresponding sparse coding problems and demonstrates that they can be solved using convex and non‐convex optimization approaches. When the data morphology is not known or cannot be analyzed, it must be learned from training data, thereby formulating dictionary learning problems. This article addresses two different dictionary learning paradigms. In an unsupervised scenario, dictionary learning involves the alternating or joint resolution of sparse coding and dictionary updating. Another option is to create a recurrent neural network by unrolling algorithms designed to solve sparse coding problems. These networks can then be used in a supervised learning setting to facilitate the training of dictionaries via forward‐backward optimization. This article lists numerous applications in various domains and outlines several directions for future research related to the sparse prior.This article is categorized under: Statistical Learning and Exploratory Methods of the Data Sciences > Modeling Methods Statistical and Graphical Methods of Data Analysis > Modeling Methods and Algorithms Statistical Models > Nonlinear Models

Культурные и лингвокультурные коды: теоретический обзор

The review paper aims to summarize scientific theoretical knowledge on the problem of codes presented in its humanitarian aspect. The paper provides various points of view on the essence, composition, structure and functioning of codes in general, culture and linguoculture codes in particular. The interaction of verbal and non-verbal codes is discussed. Special attention is paid to such a variety of linguoculture codes as figurative codes. The scientific novelty lies in the fact that the authors of this review paper attempt to provide insight into the concept of culture and linguoculture codes, to demonstrate scholars’ diverse opinions, coinciding views and their disagreements on this issue, which gives a detailed idea of the current state of the issue. As a result of studying various points of view of Russian linguists, semiologists and scholars in culture studies on the essence, composition, structure and functioning of codes, the review demonstrates the high importance attached to the notion of code within the entire spectrum of the humanities and the great effectiveness of the theory of codes, which acts as a general scientific epistemology that makes it possible to consider society, culture and language in a single system of categories. In addition, by extracting and bringing together the disparate features presented in the works on the subject under consideration, the review paper presented a list of essential (categorical) features collectively forming the notion of ‘culture code’.

Heat and mass transfer phenomenon and aligned entropy generation with simultaneous effect for magnetized ternary nanoparticles induced by ferro and nano-layer fluid flow of porous disk subject to motile microorganisms

This articles focus the dynamics of fluid conveying ternary solid particles, nano-layer, and magnetic field effects subject to porous disks. The magnetized ternary nanoparticles induced by Ferro and nano-layer are considered due to their unusual characteristics like extraordinary thermal conductivity, which are significant in advanced nanotechnology, heat exchangers, material sciences, and electronics. To avoid possible sedimentation of tiny particles, the motile microorganisms are also considered in the elaborated fluid problem. The main objective of this comprehensive study is the enhancement of heat transportation. In this study, we also investigate the physical dynamics of entropy generation, particularly emphasizing viscous dissipation related to joule heating effects. The mass transfer equation was employed to monitor the chemical interaction with diverse nanoparticles. The results of comparative and numerical validation agree well. The approach of stable and accurate numerical boundary value problem of fourth order code (bvp4c) is applied to solve the nonlinear system of ordinary differential equations. Many useful engineering results are summarized here, including the skin friction coefficient ( C f ) , Nusselt number (Nu), Sherwood number (Sh), and motile number (Nn). For both porous disks, several non-dimensional parameter effects are depicted graphically and tabulated. The results show that the increasing the number of nanolayer particles slows the rate of the temperature profile in both porous disks, associated with the expansion ratio, Reynolds number, and magnetic field number. Moreover, increasing the values of the density ratio number results in an increase in the flow of microorganisms profile in both porous disks. Increasing the values of the diffusivity parameters and the temperature difference enhances the flow of entropy generation.

Experimental and numerical research on the lateral behaviour of glued timber frame structures with and without X-type diagonal bracing

The advanced processing technology of glued wood can provide strong support for the construction and application of the modern timber structures. The modern timber structure can meet the requirements of low-carbon development goals and natural living standards, but there still exist some technical difficulties to research, such as seismic performance and design code problems. Hence, this paper presents the lateral behaviour of glued timber frame structures with and without X-type diagonal bracing by experimental and numerical research methods based on these problems. Two single-layer single-span bare glued-laminated timber (GLT) frame specimens and two GLT frames infilled with X-type diagonal bracing specimens with a 1:1.5 scale were designed to investigate the lateral behaviours under the cyclic loading tests. Three types of beam-column joint connectors (the exposed type with infilled steel plate, the coated type with infilled steel plate and the extended coated type with infilled steel plate) were designed to guarantee the effective connection between components. The failure mode, hysteretic characteristics, lateral load-bearing capacity, stiffness degradation, deformation and the lateral load resistance cooperative working mechanism between X-type diagonal bracing and GLT frame of specimens were analyzed. The test results present that the lateral behaviour of the GLT frame is significantly improved after being infilled with the X-shaped diagonal bracing, and the yield lateral load-bearing capacity and the elastic stiffness of the coated type beam-column joint connection in the GLT frame were 1.876 and 1.36 times than that of the specimen with exposed type beam-column joint connection, respectively. The beam-column joint of the bare GLT frame specimen is failure before the column-base joint. The diagonal bracing joints of the GLT frame specimen infilled with the X-shaped bracing were failures first, and then the beam-column and the column-base joints of the GLT frame were damaged. For the specimen infilled with the X-type diagonal bracing, the lateral resistance load was borne by the GLT frame and diagonal bracing, in which the percentage of the lateral load borne by the diagonal brace gradually decreases, while the percentage of the lateral load borne by the GLT frame gradually increases. In addition, the load-deformation relationships of the specimen joints were derived. Based on these relationships, the numerical analysis of the specimen was carried out to study the influences of GLT frame span-depth ratio, the slenderness ratio of GLT diagonal bracing and the wall thickness of steel tube diagonal bracing on the lateral resistance of this structural system.