Type Boundary Research Articles

Spectral Properties of The Finite System of Klein-Gordon S-Wave Equations with Condition Depends on Spectral Parameter

The spectral characteristics of the operator L is studied where L is defined within the Hilbert space L2(R+,CV ) given by a finite system of Klein-Gordon type differential equations and boundary condition depends on spectral parameter. The research of the Klein-Gordon type operator continues to be an important topic for researchers due to the range of applicability of them in numerous branches of mathematics and quantum physics. Contrary to the previous works, we take the potential as complex valued and generalize the problem to the matrix Klein-Gordon operator case. The spectrum is derived by determining the Jost function and resolvent operator of the prescribed operator. Further, we provide the conditions that must be met for the certain quantitative properties of the spectrum.

Spatial Morphology and Geographic Adaptability of Traditional Villages in the Hehuang Region, China

Understanding the spatial morphology and geographic adaptability of traditional settlements is crucial for their preservation and management. Accordingly, this study employs Hehuang region, China, as a case study, adopting an integrated approach that combines morphological type analysis and boundary shape index. This comprehensive methodology systematically investigates the spatial morphological features and reveals the geographic adaptability of the two types of traditional villages, which are river valley and mountain types. Specifically, the results demonstrate that: (1) The boundary morphology of river valley-type traditional villages is primarily composite, with a regular and compact overall tendency, creating a spatial pattern consisting of mountains and water bodies surrounding farmland and villages, which conveniently supports agricultural production. Their streets and alleys are mainly fishbone-shaped, dendritic, and grid-shaped. (2) Mountain-type traditional villages also exhibit composite boundary morphology but with lower compactness, higher fragmentation, and more pronounced belt-shape characteristics. Their spatial pattern facilitates agriculture and animal husbandry, with streets and alleys being predominantly grid-shaped, S-shaped, and Z-shaped. (3) The spatial morphology of both types of villages is well-adapted to local terrain and climate conditions, as well as to the resident’s requirements for water use and disaster prevention, which reflects the wisdom of the Hehuang region’s ancestors regarding settlement construction. This study contributes to comprehending the spatial characteristics and geographic adaptability of traditional villages in a multicultural area and provides a significant reference for advancing analogous traditional settlement protections and rural revitalization initiatives.

Physics-based and data-driven prediction method for features and type boundaries of oblique detonation wave systems in hydrogen-air mixtures

Physics-based and data-driven prediction method for features and type boundaries of oblique detonation wave systems in hydrogen-air mixtures

ON A SPECTRAL PROBLEM FOR THE LAPLACE OPERATOR WITH MORE GENERAL BOUNDARY CONDITIONS

In this paper, we consider a spectral problem for the Laplace operator with more general boundary conditions in a unit disk B1. In the special cases, the boundary conditions inlude periodic and Samarskii-Ionkin type boundary conditions. The main important property of our problem is its non-self-adjointness, which causes number of difficulties in their analytical and numerical solutions. For example, the Fourier method of separation of variables cannot be applied directly to our problem. Therefore, the possibility of separation of variables is justified in this paper. Namely, we present a method that reduces solution of the problem to a sequential solution of two classical local boundary value problems. By using this method, we construct all eigenfunctions and eigenvalues of the problem in explicit forms. Moreover, completeness of the system of the eigenfunctions is proved in L2 (B1). Notably, our result generalises the special case of the result on the two-dimensional periodic boundary value problem for the Laplace operator obtained in [1–2].

The mechanism for the self-accommodation microstructure of α variants during phase transformation of the Zr–2.5Nb Alloy

Although variant selection during the phase transformation of zirconium (Zr) alloys has been studied extensively, studies on the formation mechanism of microstructural characteristics related to α variant selection remain limited. The formation mechanisms of the self-accommodation morphology and inter-variant boundary characteristics of α variants in homogenized Zr–2.5Nb alloy cooled by water quenching (WQ), furnace cooling (FC), and air cooling (AC) were systematically investigated from the perspective of local strain during phase transformation. The α variants exhibited triangular morphologies in both the WQ and AC samples, and a colony morphology in the FC sample. Further, there were five types of inter-variant boundaries: Type I <0 0 0 1>/10.53°, Type II 〈112¯0〉/60°, Type III 〈1.377‾1¯2.3770.359〉/60.83°, Type IV 〈10‾553¯〉/63.26°, and Type V 〈12.38‾1.380〉/90°. The proportion of Type II is up to 98% in the AC sample and 57.9% in the WQ sample; the Type I was very low in all three samples; and a high proportion of the Type V was observed in the FC sample (23.6%). The self-accommodation morphology of α variants is closely related to the equivalent strain (εVM) during the variant selection. Theoretical calculations indicated that, for a specific 2-variant combinations, there were always one or more 3-variant combinations with a lower εVM than the 2-variant combinations. A lower εVM contributes to the presence of 3-variant combinations, which forms a triangle morphology. The formation of inter-variant boundaries is determined by the type and frequency of variants as well as the εVM of the 2-variant combinations. The order of the mean values of εVM for the five types of boundaries was Type II (0.0757), Type III (0.0859), Type IV (0.1012), Type V (0.1112), and Type I (0.1307). That is, Type II is the easiest and Type I is the most difficult, which resulted in a very high fraction of Type II and a very low fraction of Type I in the WQ, AC, and FC samples. The presence of a high fraction of Type V in the FC sample was related to the type and fraction of each variant.

Detachment of the Subducting Slab in Ancient Subduction Zones Discerned Using Machine Learning

AbstractIdentification of complex geochemical signatures of basalts from various tectonic settings using trace elements contents is still challenging due to uncertainties in existing classification diagrams and machine‐learning attempts. To address this, we trained a machine‐learning model using a random forest classifier on trace element concentrations of a global basalt‐dataset, categorized by types of tectonic plate boundary—destructive or constructive—at which they formed. Achieving an accuracy exceeding 98%, the model efficiently extracts the distinctive characteristics from each basalt type. When applied to the Bangong‐Nujiang suture zone in central Tibet, the model reveals that the basalts exhibited features of both boundary types prior to 108–107 Ma before transitioning to solely destructive characteristics. This transition is likely to be caused by the detachment of a descending oceanic slab, aligning with existing geological evidence. This case study highlights the promising potential of machine learning models, trained on simplified basalt types, in more accurately tracing lithospheric evolution.

XRD and EBSD evaluation on deposition behavior and microstructure characteristic of HVOF sprayed 304SS coating on aluminum substrate

304 stainless steel (304SS) coating was deposited on 6061-T6 aluminum alloy substrate using High Velocity Oxygen Fuel Spraying (HVOF) for the purpose of heavy-load coatings on lightweight structural designing. The deposition behavior, phase composition and microstructure of such a 304SS coating were studied by means of SEM, EDS, XRD and EBSD to reveal the deposition mechanism and microstructure evolution. The bonding strength and microhardness of the coating were consequently characterized. Results revealed that the deposition morphology of sprayed 304SS particles on the surface of aluminum alloy substrate mainly exhibits embedded and adhered character, with interlayer adhered type. The HVOF sprayed 304SS coating consisted of austenite, ferrite and martensite phases, martensitic transformation occurred in the thermal spraying process, and was characterized by a fine grain and dominated by high angle grain boundaries (HAGB), because of the phase distribution, grain size, stress, and grain boundary type were directly associated with the molten state of sprayed particles in the coating as EBSD analyzed. The HVOF sprayed 304SS coating presented high bond strength above 52.6 MPa, and microhardness (345.4 HV0.1), was about 1.6 times higher than the original 304SS feedstock powders and 3.6 times to the substrate, that was of a combination factors of grain refinement and martensitic strengthening in the coating.

Deep Learning Analysis of Solid Electrolyte Interface Microstructures in Lithium-Ion Batteries

Understanding the structure of the solid-electrolyte interface (SEI) in lithium-ion batteries (LIBs) is crucial for improving battery performance and safety. This study introduces a novel deep learning (DL) framework to analyze transmission electron microscopy (TEM) images of SEI, specifically focusing on identifying different types of grains and grain boundaries. Utilizing advanced machine learning (ML) algorithms, including deep convolutional neural networks, our approach enables the accurate segmentation and classification of complex microstructural features in SEI layers based on the experimental high-resolution TEM images.The DL model was trained on a comprehensive dataset of simulated SEI TEM images, generated through density functional theory (DFT) calculations and cryogenic high-resolution TEM (cryo-HRTEM) imaging. These simulations provided a diverse range of SEI microstructures, reflecting the polycrystalline nature of real battery interfaces. The model's ability to discern between various grains and grain boundaries in the SEI was fine-tuned through this training process, ensuring high accuracy and reliability in subsequent experimental image analyses.Experimental validation was performed using cryo-HRTEM images of lithium-based batteries' SEI layers. The results demonstrated the model's proficiency in identifying and classifying different grain and grain boundary types, with significant accuracy. Particularly, the model successfully mapped the distribution of Li2O, LiF, and Li2CO3 components within the SEI, as well as adeptly identified the crystallographic orientations of grains, such as the LiF(111)/Li2CO3(200) and Li2O(111)/Li2CO3(111) boundaries, unraveling the complex structure of the SEI at a nanoscopic level. Consequently, these structural features were correlated with ion diffusion pathways and potential sites for lithium dendrite formation – a detrimental phenomenon in LIBs leading to thermal runaway.This DL-based analysis provides new insights into the microscopic mechanisms governing ion transport and degradation in battery SEI layers. By offering a detailed characterization of grain and grain boundary structures, our method sets the groundwork for targeted improvements in battery design and materials selection. The study underscores the potential of integrating ML with advanced microscopy techniques to unravel the complex interplays within battery materials, propelling the field towards more resilient and efficient energy storage solutions.VY and TAK gratefully acknowledge financial support from the Department of Defense (DoD) Office of Naval Research (ONR) through the Defense Established Program to Stimulate Competitive Research (DEPSCoR).

Single-crystal structure formation in laser directed energy deposited Inconel 718 through process parameter optimization and substrate orientation tuning

A transverse grain boundary perpendicular to the applied loading direction is normally considered a main reason for the deterioration of the mechanical properties of nickel-based superalloys at high temperatures. Therefore, reducing or even eliminating these types of grain boundaries can effectively delay failure and improve high-temperature mechanical properties. In this study, the feasibility of process parameter optimization and substrate rotation was explored for fabricating single-crystal Inconel 718 specimens during laser directed energy deposition (LDED). The study determined that optimizing the process parameters was dependent on the ability to enlarge the [001] region at the bottom of the melt pool as much as possible. Simultaneously, ensuring that the remelting depth exceeded the stray grain region height at the top of the melt pool was necessary. Therefore, that the stray grains can be fully erased during the subsequent deposition process. Accordingly, an Inconel 718 single-walled specimen (height: 20 mm) with a full single-crystal structure was successfully fabricated using LDED for the first time. However, this approach remains insufficient for fabricating a block with a single-crystal structure, as SGs appear readily in the overlapping regions. Substrate rotation was further considered, where ensuring that one side of the melt pool was in the [001]-grain region was critical. Although the other side of the melt pool featured SGs, they were eliminated through the following overlapping process, as the SG region in the current melt pool corresponded to the [001]-grain region in the next melt pool. Through these two approaches, a small-format single-crystal block with dimensions of 27 × 8.3 × 1.3 mm (length × width × height) was successfully fabricated. Because the Inconel 718 superalloy is not specifically designed for single-crystal structure generation, a large-format block with a single-crystal structure still cannot be fabricated using these approaches. Nevertheless, the findings remain insightful because they demonstrate a wider range of variable microstructures achievable with additive manufacturing processes than with traditional forming processes such as casting or forging and may provide more opportunities for improving the mechanical properties. In addition, the preparation of a small-format single-crystal structure has significant applications in repairing damaged components such as aeroengine blades.

Revealing Different Types of Grain Boundaries in Perovskite Films by Intensity-dependent Fluorescence Lifetime Imaging Microscopy

Revealing Different Types of Grain Boundaries in Perovskite Films by Intensity-dependent Fluorescence Lifetime Imaging Microscopy

Controls of sedimentary-diagenetic evolution on rock physics properties in Precambrian-Lower Paleozoic ancient carbonate reservoirs

The Precambrian-Lower Paleozoic ancient carbonate reservoirs are pivotal for onshore hydrocarbon exploration in China. Nevertheless, their intricate diagenetic history leads to apparent inter- and intra-reservoir heterogeneity, strongly impacting the physical responses. Deciphering the rock physical characteristics compatible with geological processes is imperative for interpreting the geophysical responses of these reservoirs. To address this, rock physical experiments under reservoir conditions were conducted for carbonate rocks formed in different sedimentary systems from a geological perspective. The results illustrated that sedimentary-diagenetic evolution determines the material composition, dolomite genesis, and pore evolution, ultimately defining the two most critical parameters, load-bearing frame, and pore structure, controlling the physical properties of ancient carbonate rocks. Reservoir properties (porosity and permeability) are enhanced by strong hydrodynamic conditions that facilitate primary pore development, penecontemporaneous dissolution leading to secondary dissolved pores, early-stage dolomitization preserving pre-existing pores, and multi-stage tectonic movement forming microcracks (at the plug scale) with superior transport capacity. Concerning seismic properties, the slight decrease in P-wave velocity reflects that dissolution shapes the pores into a larger but stiffer shape. The significant decrease in P-wave velocity could be attributed to two factors, including weaker crystal contact boundary types formed due to different provenance, strong evaporation and silicification, and microcracks developed in regions with intense tectonic activities. Furthermore, these crystal contact boundary and pore structure types can be effectively identified by the difference in VP/VS ratio. This study enhances the understanding of rock physics in ancient carbonate reservoirs, which is relevant to the exploration of such reservoirs.

Stress-driven nonlocal integral model with discontinuities for transverse vibration of multi-cracked non-uniform Timoshenko beams with general boundary conditions

We present a formulation for the size-affected vibration study of multi-cracked non-uniform Timoshenko beams based on the well-posed stress-driven nonlocal elastic theory with discontinuities. The beam ends are assumed to be constrained by elastic springs with translational and rotational stiffness to simulate general boundary conditions. The presence of cracks divides the beam into segments connected by translational and rotational springs, and compatibility conditions are established to address the geometric discontinuities introduced by these cracks. The stress-driven constitutive equations are integrated into an equivalent differential form, equipped with a set of constitutive boundary conditions at the two ends of the entire structure and multi-sets of constitutive continuity conditions at the junctions of the sub-structures. To solve the equations of motion, the constraint conditions and the integrals involved, we employ the differential quadrature method (DQM) alongside an interpolation quadrature formula, which allows us to efficiently compute the frequencies of the cracked beams across various boundary types. After validating our approach against results in the existing literature, we present numerical studies that examine the effects of the nonlocal parameter, the slope of the beam’s thickness variation, crack location, severity, number, and the stiffness of the springs on the vibrational behavior of the beams.

On the atomistic origin of internal length scale in strain-gradient plasticity models: The case of grain boundary structures and energies

The mechanical behavior of polycrystalline materials is controlled by microstructural size effects such as grain size or precipitate size. Various models of strain gradient plasticity have been proposed to capture such size effects, many of which have incorporated geometrically-necessary dislocation (GND) densities to introduce characteristic internal lengths. Recent developments have focused on models that incorporate a GND density into the internal energy functional. In such models, one needs to physically justify the functional form chosen and quantify the inherent internal length parameter. Our present study aims at probing relevant forms and internal length values in the case of grain boundary (GB) atomistic structures and core energies. We use an atomistic-to-continuum crossover approach that predicts an atomistic structure dependent GB energy by molecular static simulations, which is then recovered at the continuum-level by using a strain gradient, atomistically informed, field dislocation mechanics fast Fourier transform model. This allows (i) delineating the atomistic structure of GBs using an equivalent Nye GND density, and (ii) capturing the associated continuous elastic fields in the GB core area. We probe (i) a generalized non-quadratic GND density dependent energy functional to account for the core energy of defects, and (ii) elucidate the contributions of core versus elastic energy to the overall GB excess energy. We investigate and discuss the possible relevant choices for the energy functional form, as well as the physical origin of the inherent internal length parameter and its dependence to the types of grain boundaries, atomistic structures, and spatial resolution.

Inhibitory effect of low-angle grain boundaries on the creep behavior of gradient nano-grained Cu: A molecular dynamics study

Gradient nano-grained (GNG) structures are renowned for their superior strength-toughness synergy. Within GNGs, low-angle grain boundaries (LAGBs), a type of low-energy grain boundary, have been identified and contribute to the mechanical and thermal stability of materials. This study uses molecular dynamics simulations to examine the impact of varying LAGB ratios on the creep behavior of GNG Cu at temperatures ranging from 720 K to 1080 K and stresses from 0.3 GPa to 0.7 GPa. The results show that LAGBs significantly enhance creep resistance, particularly at higher concentrations, temperatures, and stresses. LAGBs inhibit grain growth and influence mechanisms like diffusion and sliding. They suppress intragranular sliding and rotation, thus inhibiting creep. Furthermore, LAGBs prevent phase transformation from HCP to FCC and increase twin concentration, promoting deformation twinning. These findings, supported by changes in grain boundary morphology, atomic structure analysis, and statistical data, underline the critical role of LAGBs in enhancing the creep resistance of GNG metals.

Multiple environmental regulations and green technology innovation: a boundary theory perspective

Purpose Based on boundary theory, the authors try to clarify the boundaries of multiple environmental regulations. This paper aims to explore the strategic choices of multiple environmental regulations, analyze their spatial impact on green technology innovation and clarify the implementation priorities of multiple environmental regulations in various regions. Design/methodology/approach The authors construct an asymmetric response model based on the boundary theory perspective to analyze the strategic choices of different environmental regulations. In addition, dynamic spatial econometric methods are used to empirically analyze the differentiated regulatory boundaries of command-control type, market-incentive and voluntary-participation in environmental regulations and their spatial effects on green technology innovation. Findings Strict compulsory boundaries are formed in China when the command-control and market-incentive types are selected in a dynamic spatial and competitive game environment. When voluntary participation is selected, strict compulsory or loose basic boundaries are formed in each region. The command-control type is highly dependent on geographical distance, the market-incentive type is more dependent on an economic connection and the voluntary-participation type has obvious spatial spillover effects under the spatial weight matrix of geographical distance and economic connection. When Eastern China chooses voluntary participation in environmental regulation, the incentive effect on green technology innovation is the strongest. Middle China is the market-incentive type, and Western China is the command-control type. Command-control type and market-incentive type form strong complementary effects in dynamic spatial environments. Originality/value From the boundary theory perspective, this study analyzes the differentiated dynamic spatial boundaries of command-control, market-incentive and voluntary-participation in environmental regulations. Analyze the spatial impact of multiple environmental regulations on green technology innovation and clarify the implementation priorities of multiple environmental regulations in various regions.

On the Laplace equation on bounded subanalytic manifolds

We prove a trace formula for integration by parts on subanalytic bounded submanifolds of Rn\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb {R}}^n$$\\end{document}, possibly non closed. We also establish density results for W∇1,p(M)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\ extbf{W}}^{1,p}_\ abla (M)$$\\end{document}, M bounded subanalytic manifold, which is the space of the Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L^p$$\\end{document} tangent vector fields v on M for which ∇v\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ abla v$$\\end{document} is Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L^p$$\\end{document}, where ∇\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ abla $$\\end{document} is the divergence operator. We derive from these results some theorems of existence and uniqueness of solutions of the Laplace equation with Dirichlet and Neumann boundary type conditions. We then study the p-Laplace equation, for p∈[1,∞)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p\\in [1,\\infty )$$\\end{document} large.

Effect of grain size and grain boundary type on intergranular stress corrosion cracking of austenitic stainless steel: A phase-field study

A phase-field model coupled with polycrystalline microstructure is utilized to investigate the effect of grain size and grain boundary types on intergranular stress corrosion cracking in austenitic stainless steels. Considering the dilute solution environment, the free energy density of the two phases is hypothesized to be in parabolic form. The slower corrosion crack propagation rate in coarse-grained microstructures can be attributed to a higher frequency of transgranular cracking. Low-angle grain boundaries can effectively deflect intergranular corrosion cracks into grains with lower corrosion susceptibility, thereby impeding crack propagation. Twin boundaries mitigate corrosion crack propagation by reducing potential initiation sites.

Evidence of repeated zoonotic pathogen spillover events at ecological boundaries.

Anthropogenic modifications to the landscape have altered several ecological processes worldwide, creating new ecological boundaries at the human/wildlife interface. Outbreaks of zoonotic pathogens often occur at these ecological boundaries, but the mechanisms behind new emergences remain drastically understudied. Here, we test for the influence of two types of ecosystem boundaries on spillover risk: (1) biotic transition zones such as species range edges and transitions between ecoregions and (2) land use transition zones where wild landscapes occur in close proximity to heavily impacted areas of high human population density. Using ebolavirus as a model system and an ensemble machine learning modeling framework, we investigated the role of likely reservoir (bats) and accidental host (primates) range edges and patterns of land use (defined using SEDAC categories) on past spillover events. Our results show that overlapping species range edges and heightened habitat diversity increase ebolavirus outbreaks risk. Moreover, we show that gradual transition zones, represent by high proportion of rangelands, acts as a buffer to reduces outbreak risks. With increasing landscape changes worldwide, we provide novel ecological and evolutionary insights into our understanding of zoonotic pathogen emergence and highlight the risk of aggressively developing ecological boundaries.

Goal Shifts Structure Memories and Prioritize Event-defining Information in Memory.

Every day, we encounter far more information than we could possibly remember. Thus, our memory systems must organize and prioritize the details from an experience that can adaptively guide the storage and retrieval of specific episodic events. Prior work has shown that shifts in internal goal states can function as event boundaries, chunking experiences into distinct and memorable episodes. In addition, at short delays, memory for contextual information at boundaries has been shown to be enhanced compared with items within each event. However, it remains unclear if these memory enhancements are limited to features that signal a meaningful transition between events. To determine how changes in dynamic goal states influence the organization and content of long-term memory, we designed a 2-day experiment in which participants viewed a series of black-and-white objects surrounded by a color border on a two-by-two grid. The location of the object on the grid determined which of two tasks participants performed on a given trial. To examine if distinct types of goal shifts modulate the effects of event segmentation, we changed the border color, the task, or both after every four items in a sequence. We found that goal shifts influenced temporal memory in a manner consistent with the formation of distinct events. However, for subjective memory representations in particular, these effects differed by the type of event boundary. Furthermore, to examine if goal shifts lead to the prioritization of goal-relevant features in longer lasting memories, we tested source memory for each object's color and grid location both immediately and after a 24-hr delay. On the immediate test, boundaries enhanced the memory for all concurrent source features compared with nonboundary items, but only if those boundaries involved a goal shift. In contrast, after a delay, the source memory was selectively enhanced for the feature relevant to the goal shift. These findings suggest that goals can adaptively structure memories by prioritizing contextual features that define a unique episode in memory.

Non-inertia wave model approximation with stage-discharge relationship imposed at the downstream end and a space- and time-dependent lateral inflow

An analytical solution for the non-inertia wave model is presented for a lateral inflow that is uniformly distributed between any two locations. The model is solved by using the Laplace transform. A stage-discharge relation is taken at downstream boundary, and the upstream boundary is either water-depth based or flow rate based. The flow rate responses for the positions between the lateral inflow boundaries are found to be dependent on the location of observation, which is not the case for the positions downstream and upstream of the lateral inflow boundaries. The backwater effect induced by the lateral inflow is observed in the flow rate as well as the water depth, irrespective of the type of upstream boundary. For a flow rate hydrograph imposed at the upstream section, the flow rate and water-depth responses for the locations downstream to the location of lateral inflow are independent to the location of lateral inflow in contrast to the case of a water-depth hydrograph at the upstream section.