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The 3D integrated circuit (3D-IC) is garnering significant attention from academia and industry as a key technology leading the post-Moore era, offering new levels of efficiency, power, performance, and form-factor advantages to the semiconductor industry. However, thermal management in 3D-ICs presents a critical challenge that must be overcome to ensure prosperity for this technology. Unlike traditional thermal management solutions that perceive heat generation in 3D-ICs negatively and aim to eliminate it, this paper proposes, for the first time, a thermal management method that positively utilizes heat to achieve low-power operation in 3D-ICs. This approach is based on a novel discovery that circuits can reduce power consumption at higher temperatures by leveraging the temperature effect inversion (TEI) phenomenon in ultralow-voltage (ULV) operating circuits, a characteristic of low-power techniques (TEI-LP techniques). Along with a detailed explanation of this discovery, this paper introduces new thermal management technologies for practical application in 3D-ICs. Furthermore, to achieve optimal energy efficiency with the proposed technology, we develop a temperature controller essential for this purpose. The developed controller is a deep learning-based PID autotuner. This paper proves the theoretical validity of the AI control algorithm designed for this purpose and demonstrates the functional correctness and power-saving effectiveness of the developed controller through intensively conducted simulations. [ABSTRACT FROM AUTHOR]

Almost Moore mixed graphs appear in the context of the degree/diameter problem as a class of extremal mixed graphs, in the sense that their order is one unit less than the Moore bound for such graphs. The problem of their existence has been considered just for diameter 2. In this paper, we give a complete characterization of these extremal mixed graphs for diameters 2 and 3. We also derive some optimal constructions for other diameters. [ABSTRACT FROM AUTHOR]

A digraph G $G$ is k $k$‐geodetic if for any (not necessarily distinct) vertices u,v $u,v$ there is at most one directed walk from u $u$ to v $v$ with length not exceeding k $k$. The order of a k $k$‐geodetic digraph with minimum out‐degree d $d$ is bounded below by the directed Moore bound M(d,k)=1+d+d2+⋯+dk $M(d,k)=1+d+{d}^{2}+\cdots +{d}^{k}$. The Moore bound can be met only in the trivial cases d=1 $d=1$ and k=1 $k=1$, so it is of interest to look for k $k$‐geodetic digraphs with out‐degree d $d$ and smallest possible order M(d,k)+ϵ $M(d,k)+{\epsilon }$, where ϵ ${\epsilon }$ is the excess of the digraph. Miller, Miret and Sillasen recently ruled out the existence of digraphs with excess one for k=3,4 $k=3,4$ and d≥2 $d\ge 2$ and for k=2 $k=2$ and d≥8 $d\ge 8$. We conjecture that there are no digraphs with excess one for d,k≥2 $d,k\ge 2$ and in this paper we investigate the structure of minimal counterexamples to this conjecture. We severely constrain the possible structures of the outlier function and prove the nonexistence of certain digraphs with degree three and excess one, as well closing the open cases k=2 $k=2$ and d=3,4,5,6,7 $d=3,4,5,6,7$ left by the analysis of Miller et al. We further show that there are no involutary digraphs with excess one, that is, the outlier function of any such digraph must contain a cycle of length ≥3 $\ge 3$. [ABSTRACT FROM AUTHOR]

Based on an extension of Riemann sums, Moore and Yang have defined an integral notion for the context of continuous inclusion monotonic interval functions in which the limits of integration are real numbers. This integral notion generalizes the usual one for real-valued functions based on Riemann sums. In this paper we extend this approach by considering intervals as limits of integration and abolishing the inclusion monotonic restriction of the integrable interval functions. Also, such a new integration notion is used to define interval probability density functions and use it in interval probability distribution functions. [ABSTRACT FROM AUTHOR]

The complexity of chip design has consistently grown, adhering to Moore's law. In this paper, we examine a crucial step in integrated circuit design called chip macro placement. Traditionally, human experts are consulted to optimize placement for reduced power consumption, but this requires significant effort. Recently, machine learning-based methods have emerged to address this task, showing promising results. Our work aims to tackle key bottlenecks in current reinforcement learning (RL) based methods, which often suffer from sparse rewards, large state–action search spaces, and unstable training, resulting in suboptimal solutions. To address these issues, we propose a novel approach called Hierarchical Reinforcement Learning for Placement (HRLP). This method distinguishes itself in two ways. First, we introduce a hierarchical RL framework that learns human expert design patterns by assigning agent-specific placement sub-tasks (referred to as options in reinforcement learning) instead of primitive actions at each time step within an episode. Second, we generate dense rewards for each episode by calculating the difference in local wirelength and congestion. We conducted experiments on eight public chip design benchmarks, adaptec and bigblue series. Our model has an average improvement of 9.29 % and 14.25 % on Half Perimeter Wire Length (HPWL), the huge improvement shows that our method is capable of converging to a better sub-optimal than DeepPlace and providing a promising future for AI to aid the design of circuit placement. • Hierarchical reinforcement learning architecture addresses problems of sparse reward and large search space. • Design of dense reward stabilizes the convergence of training. • Design of two options significantly reduces the search space for state–action pairs. • Experiments on eight chip placement benchmarks demonstrate the effectiveness of our model. [ABSTRACT FROM AUTHOR]

Recently, it was stipulated in a publication that a missing elementary active-device termed "trancitor" by its designer could be made and could greatly simplify electronic circuits. This elementary device has been presented as a CCVS (Current Control Voltage Source), unlike a bipolar transistor which is a CCCS (Current Control Current Source). In the present paper, the electrical behavior of the CCVS-type trancitor in Silicon (Si), Germanium (Ge), Gallium arsenide (GaAs), Silicon Carbide (3C-SiC and 6H-SiC), Indium Nitride (InN) and Indium Phosphide (InP) technologies have been studied. The input-output transfer characteristics (Ix-Vy) of the p-type and n-type CCVS trancitors have been investigated. In addition, the effect of doping concentration on the n-type CCVS trancitor in Si technology has been studied. This study is based on TCAD (Technology Computer Aided Design) simulation. The results show that the Hall voltage of the CCVS trancitor depends on the electrical properties of the semiconductor material, such as carrier mobility (µ), band gap (Eg) and hole/electron effective mass (m). Moreover, these trancitors are compatible with the model proposed for the first time. The CCVS trancitor proved its worth in semiconductor technologies as well as being a missing active device that satisfies Moore's law. [ABSTRACT FROM AUTHOR]

Thermally induced stresses can build up in rigid pavements without pressure relief joints. The pressure created becomes a problem for adjacent structures such as bridges. The pressure can cause the pavement to push on the bridge and close the bridge expansion joints. This sets the stage for additional distress if not repaired quickly. This paper presents a case study where excessive pavement pressure damaged a two-span conventional bridge spanning Interstate 35 in Moore, Oklahoma. The bridge was instrumented with vibrating wire sensors to gather information on the behavior of the bridge before and after the repairs. There is a dearth of sensor verified observations of excessive pavement pressure acting on conventional bridges. The sensor data provided in-depth information on the response of the distressed bridge before and after repairs to thermal loading. Prior to the repairs the approach pavement was pushing on the bridge deck and causing the abutment backwalls to tilt toward the bridge. Following the repairs, the approach pavement is no longer pushing on the bridge deck. However, the abutment backwall is now moving in response to thermal changes in the bridge deck, likely due to excessive friction between the deck and the abutment backwall. U-shaped shaped cracking and spalling, previously observed in integral abutment bridges, was observed at this conventional abutment bridge, and the mechanisms causing these cracks and spalling are discussed. Through this study it was found that placement of pavement pressure relief joints relative to the bridge is crucial for reducing the magnitude of stress acting on the bridge. It was also found that the pavement stress acting on a bridge deck can be estimated with vibrating wire strain gauges given a baseline strain response for the approach pavement. [ABSTRACT FROM AUTHOR]

P.M. Pu and Y.M. Liu extended Moore-Smith's convergence of nets to fuzzy topology and Y.M. Liu provided analogous results to J. Kelley's classical characterization theorem of net convergence by introducing the notion of fuzzy convergence classes. In a previous paper, the authors of this study provided modified versions of this characterization by using an alternative notion of convergence of fuzzy nets, introduced by B.M.U. Afsan, named fuzzy net ideal convergence. Our main scope here is to generalize and simplify the preceding results. Specifically, we insert the concept of a fuzzy function ideal convergence class, L , on a non-empty set, X, consisting of triads (f , e , I) , where f is a function from a non-empty set, D, to the set FP (X) of fuzzy points in X, which we call fuzzy function, e ∈ FP (X) , and I is a proper ideal on D, and we provide necessary and sufficient conditions to establish the existence of a unique fuzzy topology, δ , on X, such that (f , e , I) ∈ L iff f I -converges to e, relative to the fuzzy topology δ. [ABSTRACT FROM AUTHOR]

Many decision problems concerning cellular automata are known to be decidable in the case of algebraic cellular automata, that is, when the state set has an algebraic structure and the automaton acts as a morphism. The most studied cases include finite fields, finite commutative rings and finite commutative groups. In this paper, we provide methods to generalize these results to the broader case of group cellular automata, that is, the case where the state set is a finite (possibly non-commutative) finite group. The configuration space is not even necessarily the full shift but a subshift — called a group shift — that is a subgroup of the full shift on ℤ d , for any number d of dimensions. We show, in particular, that injectivity, surjectivity, equicontinuity, sensitivity and nilpotency are decidable for group cellular automata, and non-transitivity is semi-decidable. Injectivity always implies surjectivity, and jointly periodic points are dense in the limit set. The Moore direction of the Garden-of-Eden theorem holds for all group cellular automata, while the Myhill direction fails in some cases. The proofs are based on effective projection operations on group shifts that are, in particular, applied on the set of valid space-time diagrams of group cellular automata. This allows one to effectively construct the traces and the limit sets of group cellular automata. A preliminary version of this work was presented at the conference Mathematical Foundations of Computer Science 2020. [ABSTRACT FROM AUTHOR]

Matrix factorizations in dual number algebra, a hypercomplex number system, have been applied to kinematics, spatial mechanisms, and other fields recently. We develop an approach to identify spatiotemporal patterns in the brain such as traveling waves using the singular value decomposition (SVD) of dual matrices in this paper. Theoretically, we propose the compact dual singular value decomposition (CDSVD) of dual complex matrices with explicit expressions as well as a necessary and sufficient condition for its existence. Furthermore, based on the CDSVD, we report on the optimal solution to the best rank-k approximation under a newly defined quasi-metric in the dual complex number system. The CDSVD is also related to the dual Moore--Penrose generalized inverse. Numerically, comparisons with other available algorithms are conducted, which indicate less computational costs of our proposed CDSVD. In addition, the infinitesimal part of the CDSVD can identify the true rank of the original matrix from the noise-added matrix, but the classical SVD cannot. Next, we employ experiments on simulated time-series data and a road monitoring video to demonstrate the beneficial effect of the infinitesimal parts of dual matrices in spatiotemporal pattern identification. Finally, we apply this approach to the large-scale brain functional magnetic resonance imaging data, identify three kinds of traveling waves, and further validate the consistency between our analytical results and the current knowledge of cerebral cortex function. [ABSTRACT FROM AUTHOR]

The purpose of this research work is to characterize and inform the design of (mechanical) property-graded bulk structures made from a single metallic alloy via a laser powder bed fusion (LPBF) process, with an end goal of creating repeatable/reproducible functionally-graded additively manufactured (FGAM) parts. This paper specifically investigates the manufacture of stainless steel (SS) 316L structures via a pulsed selective laser melting (SLM) process, and the underlying causes of property variations (within a functionally-acceptable range) through various material characterization techniques. For this, a design of experiments spanning the volumetric energy density (VED) based process parameter design space was utilized to investigate the range of functionally-acceptable physical/mechanical properties achievable in SS 316L. Five sample conditions (made via different process parameter combinations) were down-selected for in-depth microstructure analysis and mechanical/physical property characterization; these were suitably selected to impart a wide and controllable property range (209-318 HV hardness, 90-99.9% relative density, and 154-211 GPa modulus). It was observed that property variations resulted from combinations of porosity types/amounts, martensitic phase fractions, and grain sizes. Based on these findings, property-graded standard test specimens were designed and manufactured for further investigation-tensile specimens having a monotonic hardness change along its gauge length, four-point bending specimens with varying elastic moduli as a function of the distance from the neutral axis, and Moore's rotating beam fatigue specimens with moduli variations based on the distance from the center. Altogether, this work lays the foundation for understanding and designing the local and global mechanical performance of FGAM bulk structures. [ABSTRACT FROM AUTHOR]

This paper reports on two domains of a survey to map the religious literacy of Estonian basic school graduates undertaken in 2022 to understand how well the respondents distinguish religion as a discursive category and how much they know about basic concepts of world religions and the Estonian religious landscape. The sample consisted of 392 respondents from schools all over Estonia, both from large urban and small rural schools. The survey was conducted with an original instrument designed according to the Estonian religious landscape, the content of the National Curriculum for basic schools, the educational model of religious literacy according to Francis and Dinham, and the characterization of religious literacy by Moore, Prothero, Francis and Dinham. The results reflect the reality of the Estonian situation. Being one of the least religious countries in the world and with almost no education about religions and worldviews in public education, the students do not have enough competencies in the examined areas to operate well in a religiously diverse world. [ABSTRACT FROM AUTHOR]

The variational method for vortex flow (VF) analyses, called VF-Var (formulated in Part I), is applied to the 20 May 2013 Newcastle–Moore tornadic mesocyclone observed from the operational KTLX radar and an experimental phased-array radar. The dual-Doppler-analyzed VF field reveals the following features: The axisymmetric part of the VF is a well-defined slantwise two-cell vortex in which the maximum tangential velocity is nearly 40 m s−1 at the edge of the vortex core (0.6 km from the vortex center), the central downdraft velocity reaches −35 m s−1 at 3-km height, and the surrounding-updraft velocity reaches 26 m s−1 at 5-km height. The total VF field is a loosely defined slantwise two-cell vortex consisting of a nearly axisymmetric vortex core (in which the ground-relative surface wind speed reaches 50 m s−1 on the southeast edge), a strong nonaxisymmetric slantwise downdraft in the vortex core, and a main updraft in a banana-shaped area southeast of the vortex core, which extends slantwise upward and spirals cyclonically around the vortex core. The single-Doppler analysis with observations from the KTLX radar only exhibits roughly the same features as the dual-Doppler analysis but contains spurious vertical-motion structures in and around the vortex core. Analysis errors are assessed by leveraging the findings from Parts II and III, which indicate that the dual-Doppler-analyzed VF is accurate enough to represent the true VF but the single-Doppler-analyzed VF is not (especially for nonaxisymmetric vertical motions in and around the vortex core), so the dual-Doppler-analyzed VF should be useful for initializing/verifying high-resolution tornado simulations. Significance Statement: After the variational method for vortex flow (VF) analyses, called VF-Var (formulated in Part I of this paper series), was tested successfully with simulated radar observations in Part II and its sensitivity to vortex center location error was examined in Part III, the method is now applied to the 20 May 2013 Newcastle–Moore tornadic mesocyclone observed from the operational KTLX radar and an experimental phased-array radar. Analysis errors are assessed by leveraging the findings from Parts II and III. The results indicate that the dual-Doppler-analyzed VF is accurate enough to represent the true VF (although the single-Doppler-analyzed VF is not especially for nonaxisymmetric vertical motions in and around the vortex core) and thus should be useful for initializing/verifying high-resolution tornado simulations. [ABSTRACT FROM AUTHOR]

Conventional FETs, although serving as the backbone of modern electronics, have encountered fundamental limits in power efficiency due to the Boltzmann limit. Negative Capacitance (NC) FETs, leveraging the intriguing phenomenon of NC in certain ferroelectric materials, provide a ground-breaking solution by effectively amplifying the internal potential and enabling sub-60mV/dec switching. In this review paper, we explore the motivations behind the semiconductor industry's transition to NCFETs, including their potential to revolutionize low-power electronic devices. The concept of NC here is combined with all the transistors structures such as traditional MOSFETs, FinFETs, GAAFETs, and 2D material-based FETs. A unique insight into NCFETs is presented starting from general questions that concern regarding an NCFET. Physical concepts related to Ferroelectric NC, Transient NC, and Stabilized NC is discussed and modelling of MFS, MFIS, MFMIS structures is presented. A complete overview of NC devices pertaining to both experimental and simulation results are discussed. Several design considerations such as channel length scaling, thickness and gate stack optimization, hysteresis, material engineering, channel engineering, reliability (Self heating, Variability, Interface traps, Bias Temperature Instability, Radiation), annealing effects etc are discussed in detail. A future outlook that needs further developments to NCFET technology is also addressed which we believe will open the door to the advancements for low power electronic devices. [Display omitted] • Critically reviews the motivations behind the semiconductor industry's transition to NCFETs, including their potential to revolutionize low-power electronic devices. • A complete overview of NC devices pertaining to both experimental and simulation results are discussed. • Highlights the integration of NC concept into state of art devices such as MOSFETs, FinFET, NWFET, NSFET, and 2D material FETs. • Several design considerations such as channel length scaling, thickness and gate stack optimization, hysteresis, material engineering, channel engineering, reliability (Self heating, Variability, Interface traps, Bias Temperature Instability, Radiation), annealing effects etc are discussed in detail. • A future outlook that needs further developments to NCFET technology is also addressed. [ABSTRACT FROM AUTHOR]

The non-volatile memory devices based on traditional materials are unable to adapt to the background of the post-Moore era due to high energy consumption and low transmission speed. Therefore, the two-dimensional (2D) materials receive extensive attention on account of their excellent electrical and optical properties. The floating-gate transistors based on MoS 2 /h-BN/graphene heterojunction possess excellent storage functions. In this paper, the characteristics of MoS 2 /h-BN/graphene floating-gate transistors are investigated by manufacturing and comparing multiple devices. And the influences of the thickness of the h-BN tunneling layer on the storage functions are also explored. The device with the thickness of h-BN exceed 10 nm obtain the optimal non-volatile and photoelectric storage characteristics. Ultimately, the chosen floating-gate transistor can achieve switching ratio as high as ∼105 at working voltages below 10 V, and also achieve multi-level storage by applying pulses of different amplitudes. And the device has very excellent durability and retention after 1000 cycles working. At the same time, the device also has perfect performance in the process of alternately applying electrical pulses and optical pulses, and finally achieves storage functions of electrical writing and optical erasing. These results prove that the outstanding non-volatile and photoelectric storage characteristics can be effectively achieved in 2D materials heterojunction floating-gate transistors. Therefore, the 2D materials floating-gate transistors will be potential candidate for post-Moore non-volatile memory chip. • This research designed a MoS 2 /h-BN/graphene floating gate device with different thicknesses of tunneling layer. • The device with appropriate thickness of tunneling layer shows the excellent non-volatile storage characteristics. • The tunneling layer with appropriate thickness makes the device obtain outstanding multilevel memory function and endurance. • The hybrid photoelectric storage can be achieved by simultaneously applying electrical and optical pulses. [ABSTRACT FROM AUTHOR]

Cellular automaton (CA) models have been used to study pedestrian evacuation for many years. The time step and pedestrian evacuation neighbourhood rules are core elements of the CA models for the study of pedestrian dynamics, which have different consequences under different conditions and, therefore, need to be taken seriously. In this paper, we combine pedestrian aggressiveness with the individual's environment and consider the pros and cons of each of their choices to optimise aggressiveness, and we discuss the impact of time step and neighbourhood rules on pedestrian dynamics under competitive conditions. Multi-velocity two-dimensional floor field cellular automaton (FFCA) is used to consider the impact of aggressiveness on speed and spatial competitiveness. After we optimise aggressiveness, the total evacuation time differs greatly from before in the multi-step method model (MSMM) when pedestrian evacuation follows Moore's neighbourhood rule. When pedestrian evacuation follows von Neumann's neighbourhood rule, in the velocity ratio method model (VRMM) and the MSMM, the total evacuation time changes with aggressiveness in the same trend, first showing the phenomenon of 'faster is faster' and then 'faster is slower', but the greater aggressiveness is, the greater the difference in evacuation time is between the two models. When pedestrian evacuation follows Moore's neighbourhood rule, the total evacuation time has opposite trends to aggressiveness under the VRMM and the MSMM. In addition, in the VRMM, the total evacuation time of pedestrians following von Neumann's neighbourhood rule is always much greater, almost twice as long, than when following Moore's neighbourhood rule. In the MSMM, the difference in the total pedestrian evacuation time following different neighbourhood rules is much more complicated. • Pedestrian aggressiveness is optimised, considering the pedestrian's environment and the pros and cons of the choices, and compared to when it is unoptimised. • A multi-step method model for pedestrian evacuation is proposed and compared with the speed ratio method model, and how to deal with the conflicts caused by the multi-step method is explained. • Highlight the impact of the coupling effects of different neighbourhood rules and time step methods on pedestrian evacuation when considering aggressiveness. [ABSTRACT FROM AUTHOR]

This paper examines the effects of four significant tornadoes on housing prices in Moore, Oklahoma. We use a hedonic difference-in-difference approach by considering transactions made preceding and following major tornadic events in Moore (occurring in 1999, 2003, 2010, and 2013). Our dataset spans nearly 30,000 housing transactions between 1990 and 2020. The length of tornado impacts is evaluated using a set of time indicators for the years leading up to (and after) the tornadoes. We find a 2-5% decrease in housing prices during the first year after a tornado for houses in the destructive path. However, no such impacts exist in years 2-7. We also employ three different specifications (OLS, spatial lag, and spatial error) to find the most appropriate model for considering the potential spatial processes at work. The results are largely similar across specifications. [ABSTRACT FROM AUTHOR]

Place attachment has gained considerable attention in disaster studies, though there is little consensus on how to conceptualize or measure this construct in post-disaster environments. Many of the place attachment scales used in disaster studies come from studies of recreational or high-amenity areas, and we do not know whether or to what extent these measures translate to disaster contexts. This paper addresses gaps in our understanding of place attachment in disaster contexts by reviewing the measurement of place attachment in the literature and by presenting findings from an empirical study of place attachment in a post-disaster environment, namely a survey study of survivors (n = 675) of the 2013 Moore, Oklahoma, USA, tornado. Through this study, we identified four dimensions of place attachment: place identity, place dependence, neighborhood quality, and detachment. We also identified several factors that were related to dimensions of place attachment after the disaster, including social participation, exposure, and risk perception. We close by suggesting avenues for future research. [ABSTRACT FROM AUTHOR]