Journal of Computer and System Sciences最新文献_第3页

AdapBlinker: Robust adaptive median filter approach to detect subtle eye blinks AdapBlinker：鲁棒自适应中值滤波方法检测细微眨眼

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-11 DOI: 10.1016/j.jcss.2025.103746

Hafsa Sidaq , Lei Wang , Jiancheng Chi , Hussain Haider

Nowadays, eye blink detection is gaining significant attention in human-computer interaction systems. Users are increasingly favoring interactions with their phones and computers through non-manual methods, underscoring the constraints of conventional touch interfaces. Wearable technology, such as electrooculography (EOG)-based approaches and infrared sensors (IR), can accurately detect eye blinks; nevertheless, they can be inconvenient after prolonged use. Despite this, the drawbacks of camera-based eye blink recognition techniques are blind spots and the lighting effect. Thus, this study proposes an acoustic signal-based eye blink detection system to overcome these constraints. Acoustic signals can perform fine-grained detection within localized range due to their high attenuation in the air medium. The main benefit of acoustic sensing over conventional methods is that it senses signals directly, so the user does not need to wear any sensors. The prevalence of speakers and microphones in devices is another advancement that supports acoustic sensing. In this research, we present AdapBlinker, which employs the HP ProBook 440 G5 laptop to generate acoustic signals, retrieve data, process acquired signals, and plot Fast Fourier transform (FFT) to extract eye blink signals. AdapBlinker uses an adaptive median filter that adapts to surroundings, eliminates intrusions, and detects subtle blinks. We tested AdapBlinker with thirty-four participants across three settings for five months, achieving an average eye blink detection accuracy of 97.2%.

目前，眨眼检测在人机交互系统中受到越来越多的关注。用户越来越喜欢通过非手动方式与手机和电脑进行交互，这凸显了传统触摸界面的局限性。可穿戴技术，如基于眼电图（EOG）的方法和红外传感器（IR），可以准确地检测眨眼；然而，长时间使用可能会带来不便。尽管如此，基于摄像头的眨眼识别技术的缺点是盲点和灯光效果。因此，本研究提出了一种基于声信号的眨眼检测系统来克服这些限制。由于声信号在空气介质中的高衰减，可以在局部范围内进行细粒度检测。与传统方法相比，声传感的主要优点是它直接感知信号，因此用户不需要佩戴任何传感器。扬声器和麦克风在设备中的普及是支持声传感的另一个进步。在这项研究中，我们提出了AdapBlinker，它使用HP ProBook 440 G5笔记本电脑来产生声信号，检索数据，处理采集的信号，并绘制快速傅里叶变换（FFT）来提取眨眼信号。AdapBlinker使用自适应中值滤波器来适应周围环境，消除干扰，并检测细微的眨眼。我们对34名参与者进行了为期5个月的三种设置测试，达到了97.2%的平均眨眼检测准确率。

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引用次数: 0

On solution discovery via reconfiguration 通过重新配置发现解决方案

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-11 DOI: 10.1016/j.jcss.2025.103747

Michael R. Fellows , Mario Grobler , Nicole Megow , Amer E. Mouawad , Vijayaragunathan Ramamoorthi , Frances A. Rosamond , Daniel Schmand , Sebastian Siebertz

The dynamics of real-world applications and systems require efficient methods for improving infeasible solutions or restoring corrupted ones by making modifications to the current state of a system in a restricted way. We propose a new framework of solution discovery via reconfiguration for constructing a feasible solution for a given problem by executing a sequence of small modifications starting from a given state or configuration. Our framework integrates and formalizes different aspects of classical local search, reoptimization, and combinatorial reconfiguration. We exemplify our framework on a multitude of fundamental combinatorial problems, namely Vertex Cover, Independent Set, Dominating Set, and Coloring. We study the classical as well as the parameterized complexity of the solution discovery variants of those problems and explore the boundary between tractable and intractable instances.

现实世界应用程序和系统的动态需要有效的方法来改进不可行的解决方案或通过以有限的方式修改系统的当前状态来恢复损坏的解决方案。我们提出了一个新的解决方案发现框架，该框架通过从给定状态或配置开始执行一系列小修改来构造给定问题的可行解决方案。我们的框架集成并形式化了经典局部搜索、再优化和组合重构的不同方面。我们在许多基本的组合问题上举例说明我们的框架，即顶点覆盖、独立集、支配集和着色。我们研究了这些问题的解发现变体的经典复杂度和参数化复杂度，并探索了易处理和难处理实例之间的边界。

引用次数: 0

A divide and conquer algorithm for deciding group cellular automata dynamics 决定群体元胞自动机动态的分治算法

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-09 DOI: 10.1016/j.jcss.2025.103749

Niccolò Castronuovo , Alberto Dennunzio , Luciano Margara

We prove that many dynamical properties of group cellular automata (GCA) can be decided by decomposing them into a set of much simpler GCA, provided those properties are decidable for such simpler GCA. Specifically, we provide a novel algorithmic technique that decomposes the GCA under investigation into a finite number of GCA, some defined on abelian groups, while others, if any, on products of simple non-abelian isomorphic groups. Importantly, the groups resulting from the decomposition depend only on the original group and are therefore completely independent of both the automaton and the considered property. Consequently, they do not inherit any aspect of the complexity of the automaton under investigation. We study the inheritance of the dynamical properties in the original GCA versus the same properties in the GCA obtained through decomposition. The latter turn out to be significantly easier to analyze than in the original GCA. Then, we show that injectivity, surjectivity, and equicontinuity/sensitivity to initial conditions can be decided by testing them in the smaller GCA produced by the decomposition. Moreover, we prove that the topological entropy of a GCA can be computed, provided one knows how to compute it for GCA defined on products of simple non-abelian isomorphic groups – for which we explicitly prove how to compute it in the surjective case – and on abelian groups. Finally, we prove that no strongly transitive, and therefore no positively expansive, GCA defined on non-abelian groups exist.

我们证明了群元胞自动机（GCA）的许多动力学性质可以通过分解成一组更简单的GCA来确定，只要这些性质对于这种更简单的GCA是可确定的。具体来说，我们提供了一种新的算法技术，将所研究的GCA分解为有限数量的GCA，其中一些定义在阿贝尔群上，而另一些（如果有的话）定义在简单非阿贝尔同构群的乘积上。重要的是，分解产生的组仅依赖于原始组，因此完全独立于自动机和考虑的属性。因此，它们不继承所研究的自动机复杂性的任何方面。我们研究了原始GCA中动态特性的继承性与通过分解得到的GCA中相同特性的继承性。后者比原来的GCA更容易分析。然后，我们证明了注入性、满射性和对初始条件的等连续性/灵敏度可以通过在分解产生的较小GCA中测试来确定。此外，我们证明了一个GCA的拓扑熵是可以计算的，只要我们知道如何计算定义在简单非阿贝尔同构群的乘积上的GCA（我们明确地证明了如何在满射情况下计算它）和阿贝尔群上的GCA。最后，我们证明了在非阿贝尔群上不存在强传递因而不存在正可扩张的GCA。

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引用次数: 0

Core stability in additively separable hedonic games of low treewidth 低树宽的可加可分享乐对策的核心稳定性

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-09 DOI: 10.1016/j.jcss.2025.103748

Tesshu Hanaka , Noleen Köhler , Michael Lampis

Additively Separable Hedonic Games (ASHGs) are coalition-formation games where we are given a directed graph whose vertices represent n selfish agents and the weight of each arc uv denotes the preferences of u for v. We revisit the computational complexity of the well-known notion of core stability of symmetric ASHGs, where the goal is to construct a partition of the agents into coalitions such that no group of agents would prefer to diverge from the given partition and form a new coalition. For Core Stability Verification (CSV), we first show the following hardness results: CSV remains coNP-complete on graphs of vertex cover 2; CSV is coW[1]-hard parameterized by vertex integrity when edge weights are encoded in unary; and CSV is coW[1]-hard parameterized by tree-depth even if all weights are from

{- 1, 1}

. We complement these results with essentially matching algorithms and an FPT algorithm parameterized by the treewidth tw plus the maximum degree Δ (improving a previous algorithm's dependence from

2^{O (tw Δ^{2})}

to

2^{O (tw Δ)}

). We then move on to study Core Stability (CS), which one would naturally expect to be even harder than CSV. We confirm this intuition by showing that CS is

Σ_{2}^{p}

-complete even on graphs of bounded vertex cover number. On the positive side, we present a

2^{2^{O (Δ tw)}} n^{O (1)}

-time algorithm parameterized by

tw + Δ

, which is essentially optimal assuming the Exponential Time Hypothesis (ETH). Finally, we consider the notion of k-core stability: k denotes the maximum size of the allowed blocking (diverging) coalitions. We show that k-CSV is coW[1]-hard parameterized by k (even on unweighted graphs), while k-CS is NP-complete for all

k \geq 3

(even on graphs of bounded degree with bounded edge weights).

加法分离变量享乐游戏(ASHGs)结盟是游戏,我们给出了一个有向图的顶点代表n自私的代理和每个电弧紫外的重量表示偏好的u v .我们重温著名的计算复杂度的概念核心稳定对称ASHGs,目标是构造一个分区的代理商等联盟,没有群宁愿偏离给定的分区和组建一个新的联合政府。对于核心稳定性验证（CSV），我们首先证明了以下硬度结果：CSV在顶点覆盖2的图上保持conp完全；当边权为一元编码时，CSV是顶点完整性的coW[1]-hard参数化；即使所有权值都来自{−1,1}，CSV仍然是由树深度参数化的coW[1]-hard。我们用基本匹配的算法和由树宽tw加上最大程度Δ参数化的FPT算法来补充这些结果（将先前算法的依赖性从2O（twΔ2）提高到2O（twΔ））。然后我们继续学习核心稳定性（CS），人们自然会认为它比CSV更难。我们通过证明CS即使在有界顶点覆盖数的图上也是Σ2p-complete来证实这个直觉。在积极的方面，我们提出了一个由tw+Δ参数化的22O（Δtw）nO(1)时间算法，该算法本质上是最优的，假设指数时间假设（ETH）。最后，我们考虑了k核稳定性的概念：k表示允许的阻塞（发散）联盟的最大大小。我们证明k- csv是由k（即使在无权图上）硬参数化的，而k- cs对于所有k≥3（即使在边权有界的有界度图上）是np完全的。

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引用次数: 0

The power of knowledge in linear search for an escaping target 知识在线性搜索逃跑目标中的力量

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-08 DOI: 10.1016/j.jcss.2025.103737

Jared Coleman , Dmitry Ivanov , Evangelos Kranakis , Danny Krizanc , Oscar Morales-Ponce

We consider linear search for an escaping target whose speed and/or initial distance from the origin may be unknown to the searcher. The searcher (an autonomous mobile agent) is initially placed at the origin of the real line and can move with maximum speed 1 in either direction along the line. The oblivious mobile target that is moving away from the origin with a constant speed

v < 1

is initially placed by an adversary on the infinite line at distance d from the origin in an unknown direction. We consider four cases, depending on whether v and/or d is known to the searcher. The main contributions of this paper are new lower bounds as well as algorithms leading to new upper bounds for search in these settings. We present tight bounds for the cases when v is known. For the cases where v is unknown, we prove an optimal (up to lower order terms in the exponent) competitive ratio in the case where d is known and improved upper and lower bounds for the case where d is unknown. These results solve an open problem proposed in Coleman et al. (2022) [11].

我们考虑对逃逸目标的线性搜索，该目标的速度和/或到原点的初始距离对于搜索者来说可能是未知的。搜索器（一个自主移动代理）最初被放置在真实线路的原点，可以沿着线路以最大速度向任何方向移动。以恒定速度v<；1远离原点的遗忘移动目标最初被对手放置在距离原点d处的无限大线上，方向未知。我们考虑四种情况，取决于搜索者是否知道v和/或d。本文的主要贡献是新的下界以及在这些设置中导致新的上界搜索的算法。对于已知v的情况，我们给出了严格的边界。对于v未知的情况，我们证明了d已知情况下的最优竞争比（指数中的低阶项），并改进了d未知情况下的上界和下界。这些结果解决了Coleman等人（2022）提出的一个开放性问题。

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引用次数: 0

Induced minor models. I. Structural properties and algorithmic consequences 诱导小模型。1 .结构性质和算法后果

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-12-02 DOI: 10.1016/j.jcss.2025.103738

Nicolas Bousquet , Clément Dallard , Maël Dumas , Claire Hilaire , Martin Milanič , Anthony Perez , Nicolas Trotignon

A graph H is an induced minor of G if there exists an induced minor model of H in G, that is, a collection of pairwise disjoint subsets of vertices of G labeled by the vertices of H, each inducing a connected subgraph in G, such that two vertices of H are adjacent if and only if there is an edge in G between the corresponding subsets. In this paper, we investigate structural properties of induced minor models, including bounds on treewidth and chromatic number of the subgraphs induced by minimal induced minor models. As algorithmic applications of our structural results, we make use of recent developments regarding tree-independence number to show that if H is the 4-wheel, the 5-vertex complete graph minus an edge, or a complete bipartite graph

K_{2, q}

, then there is a polynomial-time algorithm to find in a given graph G an induced minor model of H in G, if there is one. We also develop an alternative polynomial-time algorithm for recognizing graphs that do not contain

K_{2, 3}

as an induced minor, which revolves around the idea of detecting the induced subgraphs whose presence is forced when the input graph contains

K_{2, 3}

as an induced minor. It turns out that all these induced subgraphs are Truemper configurations.

如果在G中存在H的诱导子模型，则图H是G的诱导子模型，即由H的顶点标记的G的顶点的成对不相交子集的集合，每个集合在G中诱导一个连通子图，使得H的两个顶点相邻当且仅当在G中对应的子集之间存在一条边。本文研究了诱导次要模型的结构性质，包括由最小诱导次要模型诱导的子图的树宽界和色数界。作为我们的结构结果的算法应用，我们利用最近关于树无关数的发展来表明，如果H是4轮，5顶点完全图减去一条边，或完全二部图K2，q，那么在给定的图G中有一个多项式时间算法来找到H在G中的诱导小模型，如果有的话。我们还开发了一种替代的多项式时间算法，用于识别不包含K2,3作为诱导子图的图，它围绕着检测当输入图包含K2,3作为诱导子图时强制存在的诱导子图的思想。所有这些诱导子图都是Truemper构型。

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引用次数: 0

Finding and counting patterns in sparse graphs 稀疏图中模式的发现和计数

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-11-19 DOI: 10.1016/j.jcss.2025.103728

Balagopal Komarath , Anant Kumar , Suchismita Mishra , Aditi Sethia

We consider algorithms for finding and counting small, fixed graphs in sparse host graphs. In the non-sparse setting, the parameters treedepth and treewidth play a crucial role in fast, constant-space and polynomial-space algorithms respectively. We discover two new parameters that we call matched treedepth and matched treewidth. We show that, for many patterns, finding and counting patterns with low matched treedepth and low matched treewidth can be done asymptotically faster than the existing algorithms when the host graphs are sparse. As an application to finding and counting fixed-size patterns, we discover

\tilde{O} (m^{3})

-time.¹ constant-space algorithms for graphs on at most 11 edges and

\tilde{O} (m^{2})

-time, polynomial-space algorithms for graphs on at most 9 edges.²

我们考虑在稀疏主图中寻找和计数小的固定图的算法。在非稀疏设置下，参数树深和树宽分别在快速、常数空间和多项式空间算法中起着至关重要的作用。我们发现了两个新参数，分别称为matched treedepth和matched treewidth。我们证明，对于许多模式，当主图是稀疏时，低匹配树深和低匹配树宽的模式查找和计数可以比现有算法渐进地更快地完成。作为查找和计数固定大小模式的应用，我们发现O ~ （m3）时间。1个最多11条边图的常数空间算法和O ~ （m2）时间，最多9条边图的多项式空间算法

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引用次数: 0

Maximizing the number of integer pairs summing to powers of 2 via graph labeling and solving restricted systems of linear (in)equations 通过图形标记和求解线性（in）方程的限制系统，最大化求和为2的整数对的数量

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-11-17 DOI: 10.1016/j.jcss.2025.103735

Max A. Alekseyev

We address the problem of finding sets of integers of a given size with a maximum number of pairs summing to powers of 2. By fixing particular pairs, this problem reduces to finding a labeling of the vertices of a given graph with pairwise distinct integers such that the endpoint labels for each edge sum up to a power of 2. We propose an efficient algorithm for this problem, which at its core relies on another algorithm that, given two sets of linear homogeneous polynomials with integer coefficients, computes all variable assignments to powers of 2 that nullify polynomials from the first set but not from the second. With the proposed algorithms, we determine the maximum size of graphs of order n that admit such a labeling for all

n \leq 21

, and construct the maximum admissible graphs for

n \leq 20

. We also identify the minimal forbidden subgraphs of order ≤11, whose presence prevents the graphs from having such a labeling.

我们解决的问题是找到给定大小的整数集，其中最大数目的整数对和为2的幂。通过固定特定的对，这个问题简化为找到给定图中具有成对不同整数的顶点的标记，使得每个边的端点标记之和为2的幂。我们为这个问题提出了一个有效的算法，其核心依赖于另一个算法，给定两组整数系数的线性齐次多项式，计算所有变量的2次方赋值，使第一组多项式无效，但不会使第二组多项式无效。利用所提出的算法，我们确定了所有n≤21的n阶图中允许这种标记的最大大小，并构造了n≤20的n阶图的最大允许大小。我们还确定了阶≤11的最小禁止子图，它的存在阻止了图具有这样的标记。

引用次数: 0

Gap preserving reductions between reconfiguration problems 重新配置问题之间的缺口保留减少

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-11-14 DOI: 10.1016/j.jcss.2025.103733

Naoto Ohsaka

Combinatorial reconfiguration is a brand-new field studying algorithmic problems relating to the structure of the solution space. In this paper, we study the hardness of approximate versions of reconfiguration problems. For example, in the Maxmin SAT Reconfiguration problem, we are given a satisfiable Boolean formula and a pair of its satisfying assignments. The objective is to transform one satisfying assignment into the other by repeatedly flipping the value of a single variable, while maximizing the minimum fraction of satisfied clauses throughout the transformation. We prove a series of gap-preserving reductions to give evidence that several reconfiguration problems are

PSPACE

-hard to approximate. Our starting point is a new working hypothesis called the Reconfiguration Inapproximability Hypothesis (RIH), which asserts that a gap version of Maxmin CSP Reconfiguration is

PSPACE

-hard. Our main result is

PSPACE

-hardness of approximating Maxmin 3-SAT Reconfiguration of bounded occurrence under RIH. The crux of its proof is a gap-preserving reduction from Maxmin 2-CSP Reconfiguration to itself of bounded degree. As an application of the main result, we demonstrate that under RIH, approximate versions of reconfiguration problems are

PSPACE

-hard to approximate, including Nondeterministic Constraint Logic, Independent Set Reconfiguration, Clique Reconfiguration, Vertex Cover Reconfiguration, and 2-SAT Reconfiguration. We highlight that RIH has recently been proven by Hirahara and Ohsaka (STOC 2024) and Karthik C.S. and Manurangsi (2023).

组合重构是研究与解空间结构有关的算法问题的一个崭新领域。本文研究了重构问题近似版本的硬度。例如，在Maxmin SAT重构问题中，我们给出了一个可满足的布尔公式及其一对可满足的赋值。目标是通过反复翻转单个变量的值，将一个令人满意的赋值转换为另一个赋值，同时在整个转换过程中最大化满足子句的最小比例。我们证明了一系列保持间隙的约简，以证明一些重构问题是难以近似的。我们的出发点是一个新的工作假设，称为重构不可近似性假设（RIH），它断言Maxmin CSP重构的间隙版本是PSPACE-hard的。我们的主要结果是在RIH条件下近似Maxmin 3-SAT重构的pspace -硬度。其证明的关键是从Maxmin 2-CSP重构到有界度自身的保间隙化简。作为主要结果的应用，我们证明了在RIH下，重构问题的近似版本是pspace难以近似的，包括不确定性约束逻辑、独立集重构、团重构、顶点覆盖重构和2-SAT重构。我们强调，最近Hirahara和Ohsaka （STOC 2024）以及Karthik C.S.和Manurangsi（2023）证明了RIH。

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引用次数: 0

A comparative study of the smallest probability intervals for which a binary sequence is random 对二值序列为随机的最小概率区间的比较研究

IF 0.9 3区计算机科学 Q1 BUSINESS, FINANCE

Journal of Computer and System Sciences

Pub Date : 2025-11-13 DOI: 10.1016/j.jcss.2025.103734

Floris Persiau, Gert de Cooman, Jasper De Bock

There are many randomness notions. Classically, many of them are about whether a given infinite binary sequence is random for some given probability, meaning that it is random for the i.i.d. process that assigns this probability to the outcome 1. In that case, if a sequence is random according to several randomness notions, then the probability for which it is random is the same for all these notions. Comparing randomness notions then amounts to finding out according to which of them a given sequence is random. This changes dramatically when we consider randomness for probability intervals, because here, a sequence is always random for at least one such interval, so the question is not if, but rather for which intervals, a sequence is random. We show that for many randomness notions thus generalised, every sequence has a smallest interval for which it is (almost) random. We study such smallest intervals and then use them as a way to compare the corresponding randomness notions. We establish conditions under which such smallest intervals coincide, and provide examples where they do not.

随机性概念有很多。经典地，它们中的许多都是关于给定的无限二进制序列对于某个给定的概率是否是随机的，这意味着对于将该概率分配给结果1的i.i.d.过程来说，它是随机的。在这种情况下，如果一个序列根据几个随机性概念是随机的，那么对于所有这些概念，它是随机的概率是相同的。比较随机性概念就等于找出给定序列中哪一个是随机的。当我们考虑概率区间的随机性时，这就发生了巨大的变化，因为在这里，一个序列至少在一个这样的区间内总是随机的，所以问题不是序列是否随机，而是对于哪个区间，序列是随机的。我们证明了对于许多这样推广的随机性概念，每个序列都有一个（几乎）随机的最小区间。我们研究这样的最小区间，然后用它们来比较相应的随机性概念。我们建立了这些最小间隔重合的条件，并提供了它们不重合的例子。

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引用次数: 0