Speculative design is widely used in research contexts across multiple disciplines, emphasising problem-finding over problem-solving, and involves methods for exploring possibilities that challenge ingrained assumptions. This systematic literature review analyses speculative design methods used in 52 studies within disciplines such as human–computer interaction, fashion, urban planning, and healthcare, among other fields. It presents results about the common phases and methods of speculative design that are utilised in these studies. It identifies and characterises four core phases that appear to be common within speculative design processes, namely select, explore, transform, and provoke. It shares examples of how these phases are used to achieve the goals of speculative design. The discussion section considers the process of speculative design, leading to the synthesis of a framework that visually and conceptually organises these findings to facilitate their comprehension and application. This paper contributes to the understanding of speculative design by providing a clear process that addresses gaps in its theoretical and methodological foundations.

This article explores biophilic (nature-centred) instrument design and its intersection with architecture and music. While the connection between these disciplines is often discussed figuratively, they are less often combined in practice. The Biophilic Instrument Pavilion (BIP), a site-responsive sound and light installation, serves as a model for such a collaboration using biophilic design as a unifying principle. This multidisciplinary project demonstrates spatialisation in ecological, sonic, visual and social contexts, offering insights into environmental instrument practices and collaborative creative processes.

This study synthesized 65 (quasi-)experimental studies published between 2010 and 2024 that examined the use of mobile applications to develop language learners’ vocabulary learning. Bayesian meta-analysis was adopted to assess (1) overall effect size; (2) subgroup analyses (i.e. education level, vocabulary knowledge, aspects of vocabulary learning, learning environment, sample size, mobile application type, gender, and cultural background); and (3) publication bias. A large effect size of 1.28 was found for the overall effectiveness of using mobile applications for vocabulary learning when we restricted the studies to long-term treatment duration of 10 weeks or above. Each moderator was analyzed and discussed, and implications for language teaching and research were provided.

This paper considers two supercritical branching processes with immigration in different random environments, denoted by $\{Z_{1,n}\}$ and $\{Z_{2,m}\}$, with criticality parameters µ1 and µ2, respectively. Under certain conditions, it is known that $\frac{1}{n} \log Z_{1,n} \to \mu_1$ and $\frac{1}{m} \log Z_{2,m} \to \mu_2$ converge in probability as $m, n \to \infty$. We present basic properties about a central limit theorem, a non-uniform Berry–Esseen’s bound, and Cramér’s moderate deviations for $\frac{1}{n} \log Z_{1,n} - \frac{1}{m} \log Z_{2,m}$ as $m, n \to \infty$. To this end, applications to construction of confidence intervals and simulations are also given.

Let $K^r_n$ be the complete $r$-uniform hypergraph on $n$ vertices, that is, the hypergraph whose vertex set is $[n] \, :\! = \{1,2,\ldots ,n\}$ and whose edge set is $\binom {[n]}{r}$. We form $G^r(n,p)$ by retaining each edge of $K^r_n$ independently with probability $p$. An $r$-uniform hypergraph $H\subseteq G$ is $F$-saturated if $H$ does not contain any copy of $F$, but any missing edge of $H$ in $G$ creates a copy of $F$. Furthermore, we say that $H$ is weakly $F$-saturated in $G$ if $H$ does not contain any copy of $F$, but the missing edges of $H$ in $G$ can be added back one-by-one, in some order, such that every edge creates a new copy of $F$. The smallest number of edges in an $F$-saturated hypergraph in $G$ is denoted by ${\textit {sat}}(G,F)$, and in a weakly $F$-saturated hypergraph in $G$ by $\mathop {\mbox{$w$-${sat}$}}\! (G,F)$. In 2017, Korándi and Sudakov initiated the study of saturation in random graphs, showing that for constant $p$, with high probability ${\textit {sat}}(G(n,p),K_s)=(1+o(1))n\log _{\frac {1}{1-p}}n$, and $\mathop {\mbox{$w$-${sat}$}}\! (G(n,p),K_s)=\mathop {\mbox{$w$-${sat}$}}\! (K_n,K_s)$. Generalising their results, in this paper, we solve the saturation problem for random hypergraphs $G^r(n,p)$ for cliques $K_s^r$, for every $2\le r \lt s$ and constant $p$.

Based on the characteristics of the variable pivot gait during the human load-carrying, this paper proposes a double-leg coordination assistance principle for load-carrying: assisting support of the guiding leg at the heel-pivot stage by the spring to reduce the collision, which can reduce the ankle moment of the following leg that is performing the push-off at the toe-pivot stage. A novel unpowered load-carrying exoskeleton (ULE) with a double-support closed-chain configuration is designed, and the theoretical verification is carried out. Five subjects participate in the load-carrying and metabolic cost experiments for assisting and energy-saving effect evaluation, and the angle and moment of human joints, plantar pressure, spring compression and human net metabolic rate are analyzed. Compared with carrying load by the human alone, wearing the novel ULE with spring reduces the human peak ankle moment performing the push-off by up to 11.9 ± 1.6% (Mean±SE, 10 kg), average ankle moment over the support phase by up to 36.8 ± 9.1% (Mean±SE, 5 kg) and the average vertical plantar pressure by up to 8.1 ± 1%% (Mean±SE, 15 kg). Meanwhile, wearing the novel ULE reduces the human net metabolic rate by 5.6 ± 0.5% (Mean±SE, 10 kg), 4.1 ± 0.7% (Mean±SE, 15 kg) and 5.9 ± 1.6% (Mean±SE, 20 kg). The results show that the novel ULE can provide support and joint moment assistance over the whole support phase while reducing human net metabolic rate. This study can also be applied to the powered load-carrying exoskeleton, providing a new avenue.

Neural network (NN)-based control policies have proven their advantages in cyber-physical systems (CPS). When an NN-based policy fails to fulfill a formal specification, engineers leverage NN repair algorithms to fix its behaviors. However, such repair techniques risk breaking the existing correct behaviors, losing not only correctness but also verifiability of initial state subsets. That is, the repair may introduce new risks, previously unaccounted for. In response, we formalize the problem of Repair with Preservation (RwP) and develop Incremental Simulated Annealing Repair (ISAR). ISAR is an NN repair algorithm that aims to preserve correctness and verifiability — while repairing as many failures as possible. Our algorithm leverages simulated annealing on a barriered energy function to safeguard the already-correct initial states while repairing as many additional ones as possible. Moreover, formal verification is utilized to guarantee the repair results. ISAR is compared to a reviewed set of state-of-the-art algorithms, including (1) reinforcement learning based techniques (STLGym and F-MDP), (2) supervised learning-based techniques (MIQP and minimally deviating repair), and (3) online shielding techniques (tube MPC shielding). Upon evaluation on two standard benchmarks, OpenAI Gym mountain car and an unmanned underwater vehicle, ISAR not only preserves correct behaviors from previously verified initial state regions, but also repairs 81.4% and 23.5% of broken state spaces in the two benchmarks. Moreover, the signal temporal logic (STL) robustness of the ISAR-repaired policies is higher than the baselines.

This research examines whether a machine, specifically artificial intelligence (AI), can be creative by comparing design solutions for a practical competition – a light fixture for a pediatric waiting room – among AI, collaboration efforts and a human designer. Amazon Mechanical Turk and Prolific workers observed the design solutions throughout the design process, from sketches ($ S $) to three-dimensional renderings ($ 3D $) to fully developed models in virtual waiting rooms ($ VR $). Using the well-established Creative Product Semantic Scale (CPSS), the workers rated each design solution in three distinctive stages – $ S $, $ 3D $ and $ VR $ – on three criteria – novelty (freshness or newness), resolution (relevance and logic) and style (craftsmanship and desirability). Despite some demographic discrepancies, the workers expressed general senses of happiness and calmness, resonating with the competition’s requirements. Statistical results of CPSS ratings revealed that while AI excelled in style for $ 3D $, the human designer outperformed in novelty for both $ S $ and $ VR $. Collaboration efforts surprisingly finished last. Such findings challenge current assumptions of AI’s creative ability in design research and highlight the need to be agile in the age of disruptive technologies. This research also offers guidance for product and interior designers and educators on thoughtfully integrating AI into the design process.

While the relationship between space and openness has been explored in electroacoustic music since the 1960s, and contemporary composers have shown increasing interest in contingency, recent advancements in ambisonics, sound diffusion, and VR have granted composers greater control over the spatial image presented to the listener. This article revisits the discussion of space and openness through the lens of the author’s artistic practice and compositional experience, framed by new materialism, object-oriented philosophy and relational space theory. Through case studies from the author’s work, it examines spatialisation strategies that emphasise openness and the agency of sound materials. These strategies include sound source localisation, networks of family resemblances and parametric spatialisation, aiming to create an open sound experience that maintains identity while allowing agency for the sound material, the listener and the composer. In light of current global crises, partly driven by total control and exploitation, this article advocates for rethinking compositional practices to foster open sound experiences that reflect dynamic interactions between composer, material and listener.