Partition Components Research Articles

Mass-air-mass resonance for multiple leaf partition using perforated plate

In an exchange counter, a taxi cabin, and so on, there is a partition between the user and the staff to secure safety. In contrast, the partition prevents speech communication between them. Thus, it is necessary to decline the sound insulation performance of the partition for their comfortable communication. Therefore, we have proposed producing mass-air-mass resonances by applying multiple leaf partitions to decrease the performance. The partition needs to be comprised of very thin sheets and very thin air layers to cause resonances in the frequency range of approximately 500 to 2000 Hz, which is included in voice frequency. In this study, we have realized the sound insulation decline using perforated plates instead of very thin sheets. The formulae of the resonance frequencies were derived for triple or quadruple leaf partitions when using perforated plates as partition components. Moreover, we have verified experimentally that the resonances can occur in the frequencies calculated from the formulae.

Connected graph partitioning with aggregated and non‐aggregated gap objective functions

AbstractThis article deals with the problem of partitioning a graph into connected components by optimizing some balancing objective functions related to the vertex weights. Objective functions based on the gap or range of the partition's components, that is, the difference between the maximum and minimum weight of a vertex in the component, have been already introduced in the literature. Here we introduce the notion of aggregated gap, defined as the sum of the differences between the weights of the vertices and the minimum weight of a vertex in the component. We study new connected ‐partitioning problems whose objective is a function of the components' aggregated gap, and give NP‐hardness results for these problems on general graphs. Mathematical programming formulations are proposed for these problems adopting flow‐based constraints for modeling connectivity in a partition. Even if they are introduced for the new aggregated gap problems, such formulations are rather general and apply also to the classical non‐aggregated gap problems. Extensive computational tests, both for aggregated and non‐aggregated gap problems, are performed on a set of squared grids and randomly generated graphs with up to 120 vertices, and a number of components ranging from 2 to 9. In our experiments, we test several alternative formulations for our problems providing a comparative analysis of their performance.

Distinct element modeling of the in-plane and out-of-plane response of ordinary and innovative masonry infill walls

Masonry infill walls (MIWs) are essential partition components that are often damaged during earthquakes because of their brittle nature. As a result, innovative solutions are attractive to improve performance of MIWs by reducing damage during in-plane drift or increasing damping. Examples of innovative solutions have been investigated experimentally, but mesoscale or microscale numerical modelling techniques could also be useful to evaluate performance and investigate the principal failure mechanisms of both ordinary and innovative MIWs, and subsequently optimize their design. This paper employs the Distinct Element Method (DEM) to predict the in-plane (IP) and out-of-plane (OOP) response of ordinary and innovative MIWs within RC frames. The DEM methodology used in this study account for the crushing of concrete and masonry, the shear-compression behavior of mortar and the shear behavior of a novel damping layer joint (DLJ) inserted in the MIW (named damped masonry infilled wall (DMIW)). DEM results are compared against experimental results for both MIWs and DMIWs. Two IP and four OOP experimental tests were simulated in total. The DEM simulation methodology is capable of predicting the IP and OOP load–displacement response as well as the damage patterns of the ordinary MIWs and DMIWs, although the local displacement mechanism at the DLJ locations of the DMIW varied for the OOP tests. Local stress distribution differences, as well as modeling modifications for simulating the damage pattern of DMIWs, are further discussed. Overall, the effectiveness of the DEM simulation provides confidence that it could be used to improve upon the DMIW design in the simulation environment.

Response of dry matter partition and yield components to waterlogging and sunlight shortage in different growth stages of wheat

Response of dry matter partition and yield components to waterlogging and sunlight shortage in different growth stages of wheat

Patterns of environmental variance across environments and traits in domestic cattle.

The variance in phenotypic trait values is a product of environmental and genetic variation. The sensitivity of traits to environmental variation has a genetic component and is likely to be under selection. However, there are few studies investigating the evolution of this sensitivity, in part due to the challenges of estimating the environmental variance. The livestock literature provides a wealth of studies that accurately partition components of phenotypic variance, including the environmental variance, in well‐defined environments. These studies involve breeds that have been under strong selection on mean phenotype in optimal environments for many generations, and therefore represent an opportunity to study the potential evolution of trait sensitivity to environmental conditions. Here, we use literature on domestic cattle to examine the evolution of micro‐environmental variance (CVR—the coefficient of residual variance) by testing for differences in expression of CVR in animals from the same breed reared in different environments. Traits that have been under strong selection did not follow a null expectation of an increase in CVR in heterogenous environments (e.g., grazing), a pattern that may reflect evolution of increased uniformity in heterogeneous environments. When comparing CVR across environments of different levels of optimality, here measured by trait mean, we found a reduction in CVR in the more optimal environments for both life history and growth traits. Selection aimed at increasing trait means in livestock breeds typically occurs in the more optimal environments, and we therefore suspect that the decreased CVR is a consequence of evolution of the expression of micro‐environmental variance in this environment. Our results highlight the heterogeneity in micro‐environmental variance across environments and point to possible connections to the intensity of selection on trait means.

A compact mixed integer linear formulation for safe set problems

The Safe Set Problem is a type of partitioning problem with particular constraints on the weight of adjacent partition components. Several theoretical results exist in the literature along with a mixed integer linear formulation. We propose a new, more compact, Mixed Integer Linear Program for the (Weighted) Safe Set Problem and Connected Safe Set Problem with a polynomial number of variables and constraints, based on a flow from an additional fictitious node. The model is enriched by symmetry-breaking considerations and a variable reduction subproblem. We test the model on a benchmark of small instances which underline the difficulty of solving the Safe Set Problem through mathematical programming approaches. We also compare it with the only existing formulation in the literature and find that our approach is usually more efficient on a set of benchmark instances.

Geometry of Graph Partitions via Optimal Transport

We define a distance metric between partitions of a graph using machinery from optimal transport. Our metric is built from a linear assignment problem that matches partition components, with assign...

A minimal surface criterion for graph partitioning

We consider a geometric approach to graph partitioning based on the graph Beltrami energy, a discrete version of a functional that appears in classical minimal surface problems. More specifically, the optimality criterion is given by the sum of the minimal Beltrami energies of the partition components. Since the Beltrami energy interpolates between the Total Variation and Dirichlet energies, various results for optimal partitions for these two energies can be recovered. We adapt primal-dual convex optimization methods to solve for the minimal Beltrami energy for each component of a given partition. A rearrangement algorithm is proposed to find the graph partition to minimize a relaxed version of the objective. The method is applied to several clustering problems on graphs constructed from manifold discretizations, synthetic data, the MNIST handwritten digit dataset, and image segmentation. The model has a semisupervised extension and provides a natural representative for the clusters as well.

Resolution of Adsorption and Partition Components of Organic Compounds on Black Carbons.

Black carbons (BCs) may sequester non-ionic organic compounds by adsorption and/or partition to varying extents. Up to now, no experimental method has been developed to accurately resolve the combined adsorption and partition capacity of a compound on a BC. In this study, a unique "adsorptive displacement method" is introduced to reliably resolve the adsorption and partition components for a solute-BC system. It estimates the solute adsorption on a BC by the use of an adsorptive displacer to displace the adsorbed target solute into the solution phase. The method is validated by tests with uses of activated carbon as the model carbonaceous adsorbent, soil organic matter as the model carbonaceous partition phase, o-xylene and 1,2,3-trichlorobenzene as the reference solutes, and p-nitrophenol as the adsorptive displacer. Thereafter, the adsorption-partition resolution was completed for the two solutes on selected model BCs: four biochars and two National Institute of Standards and Technology (NIST) standard soots (SRM-2975 and SRM-1650b). The adsorption and partition components resolved for selected solutes with given BCs and their dependences upon solute properties enable one to cross-check the sorption data of other solutes on the same BCs. The resolved components also provide a theoretical basis for exploring the potential modes and extents of different solute uptakes by given BCs in natural systems.

Minimal Dirichlet Energy Partitions for Graphs

Motivated by a geometric problem, we introduce a new non-convex graph partitioning objective where the optimality criterion is given by the sum of the Dirichlet eigenvalues of the partition components. A relaxed formulation is identified and a novel rearrangement algorithm is proposed, which we show is strictly decreasing and converges in a finite number of iterations to a local minimum of the relaxed objective function. Our method is applied to several clustering problems on graphs constructed from synthetic data, MNIST handwritten digits, and manifold discretizations. The model has a semi-supervised extension and provides a natural representative for the clusters as well.

Variance component analysis of body mass in a wild population of deer (Odocoileus virginianus): results from two decades of research

Context Long-term studies of large, vertebrate mammals using capture–recapture data are scarce, even though long-term ecological studies are requisite to understanding quantitative genetics and evolutionary processes that can be applied as part of management programs. Aims Objectives were to (1) partition components of variation in body mass to understand the differential effects of environmental variation on the sexes during ontogeny, to better prescribe habitat-improvement projects, and (2) estimate repeatability to assess potential for selection on body mass. Methods We used a 23-year dataset (1983–2005) of capture–recapture records of wild white-tailed deer (Odocoileus virginianus) to estimate components of variance and repeatability of body mass. We used an animal-model approach that employed the use of general linear mixed models and restricted maximum likelihood to adjust for the effects of age (i.e. fixed effect), and to partition the total phenotypic variance into among-individual (i.e. the deer), permanent environmental (i.e. year of birth) and temporary environmental (i.e. year of measurement and residual) effects (all modelled as random effects). Key results We found that body mass increased with age in both sexes, repeatability of body mass was 0.595 for females and 0.716 for males, and among-individual variation was more influential on body mass than were permanent and temporary environmental effects combined. Year of birth was more important in males than females, but changed during the course of ontogeny for both sexes. Year of measurement did not influence post-rut body mass in males, but did contribute to variation in body mass of females. Conclusions These long-term data offer insights into the sources of variation that influence body mass of deer, which can be used to understand how environmental sources of variation influence phenotypic traits, and for developing management plans and making selection decisions. Implications Knowledge of repeatability (as an upper limit to heritability) can be used to make management decisions related to selection, culling and breeding, whereas understanding environmental effects can lead to better management recommendations (e.g. habitat-improvement projects).

Bacterial plasmid partition machinery: a minimalist approach to survival

The accurate segregation or partition of replicated DNA is essential for ensuring stable genome transmission. Partition of bacterial plasmids requires only three elements: a centromere-like DNA site and two proteins, a partition NTPase, and a centromere-binding protein (CBP). Because of this simplicity, partition systems have served as tractable model systems to study the fundamental molecular mechanisms required for DNA segregation at an atomic level. In the last few years, great progress has been made in this endeavor. Surprisingly, these studies have revealed that although the basic partition components are functionally conserved between three types of plasmid partition systems, these systems employ distinct mechanisms of DNA segregation. This review summarizes the molecular insights into plasmid segregation that have been achieved through these recent structural studies.

Applications of graph theory to an English rhyming corpus

Abstract How much can we infer about the pronunciation of a language – past or present – by observing which words its speakers rhyme? This paper explores the connection between pronunciation and network structure in sets of rhymes. We consider the rhyme graphs corresponding to rhyming corpora, where nodes are words and edges are observed rhymes. We describe the graph G corresponding to a corpus of ∼ 12000 rhymes from English poetry written c. 1900, and find a close correspondence between graph structure and pronunciation: most connected components show community structure that reflects the distinction between full and half rhymes. We build classifiers for predicting which components correspond to full rhymes, using a set of spectral and non-spectral features. Feature selection gives a small number (1–5) of spectral features, with accuracy and F-measure of ∼90%, reflecting that positive components are essentially those without any good partition. We partition components of G via maximum modularity, giving a new graph, G′, in which the “quality” of components, by several measures, is much higher than in G. We discuss how rhyme graphs could be used for historical pronunciation reconstruction.

New modeling paradigms for the sorption of hydrophobic organic chemicals to heterogeneous carbonaceous matter in soils, sediments, and rocks

Heterogeneity in naturally occurring carbonaceous materials (CMs) causes sorbed hydrophobic organic compound (HOC) concentrations in soils, sediments, and rocks to occur as a combination of surface adsorption and phase partitioning, with the latter typically more linearly dependent on aqueous concentration. In this manuscript, we describe a model to simulate HOC sorption as the combined effect of adsorption to thermally altered CM and a more linear solvation-driven absorption into gel-like CM (organic matter). We describe different forms of thermally altered CM (such as soots, chars, coals, and kerogen), the manner in which these materials can serve as especially strong adsorbents, and the conditions under which they can control solid–aqueous distribution. Specific examples of model fits to soil, sediment and rock samples with identified thermally altered CM components provide a linkage between sorption components and sorbent material properties. Because both the adsorption and partition components are scalable by compound solubility, it may often be possible to estimate nonlinear isotherms for a wide range of chemicals based on comparatively few experimental measurements. Thermally altered CM is widespread in the environment and can serve as an important sorbent even when present in small quantities (especially at low concentrations of adsorbates). In this context, the sorption modeling refinements described in this work are expected to have wide applicability. Given that solid/water distribution is a central process affecting contaminant fate, such refined models are an essential element for better estimates of risk and improved remediation design.

Modular neural networks for MAP classification of time series and the partition algorithm

We apply the partition algorithm to the problem of time-series classification. We assume that the source that generates the time series belongs to a finite set of candidate sources. Classification is based on the computation of posterior probabilities. Prediction error is used to adaptively update the posterior probability of each source. The algorithm is implemented by a hierarchical, modular, recurrent network. The bottom (partition) level of the network consists of neural modules, each one trained to predict the output of one candidate source. The top (decision) level consists of a decision module, which computes posterior probabilities and classifies the time series to the source of maximum posterior probability. The classifier network is formed from the composition of the partition and decision levels. This method applies to deterministic as well as probabilistic time series. Source switching can also be accommodated. We give some examples of application to problems of signal detection, phoneme, and enzyme classification. In conclusion, the algorithm presented here gives a systematic method for the design of modular classification networks. The method can be extended by various choices of the partition and decision components.

Use of an integrated transient flow and water budget procedure to predict and partition components of local recharge.

Use of an integrated transient flow and water budget procedure to predict and partition components of local recharge.

Min-cut replication in partitioned networks

Logic replication has been shown empirically to reduce pin count and partition size in partitioned networks. This paper presents the first theoretical treatment of the min-cut replication problem, which is to determine replicated logic that minimizes cut size. A polynomial time algorithm for determining min-cut replication sets for k-partitioned graphs is derived by reducing replication to the problem of finding a maximum flow. The algorithm is extended to hypergraphs and replication heuristics are proposed for the NP-hard problem with size constraints on partition components. These heuristics, which reduce the worst-case running time by a factor of O(k/sup 2/) over previous methods, are applied to designs that have been partitioned into multiple FPGA's. Experimental results demonstrate that min-cut replication provides substantial reductions in the numbers of FPGA's and pins required.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Use of an integrated transient flow and water budget procedure to predict and partition components of local recharge

A combined transient flow and water budget (TFWB) method and accounting procedure was developed and used to measure and partition the components of recharge to a sand and gravel aquifer underlying about 6.0 m of glacial till overlain by a nearly level land surface. The TFWB procedure was used to evaluate and quantify the dynamic interaction between surface recharge, till water level (at 2–4 m), and water cycling within the soil and vadose zone. Site-specific recharge activity was highly dependent upon surface microtopography. However, the homogenizing effect of the water table, measured by capillary movement of water through the vadose and soil zone, substantially offset the effects of surface and soil spatial variability and allowed relatively uniform estimates of local recharge at individual measurement sites. Substantial internal cycling of water within the soil and vadose zone was caused by the interaction of surface infiltration variability and water redistribution at the water table, even for measurement sites having little direct surface recharge activity. Through internal cycling, a single volume of water originating at the surface frequently passed through more than one soil and vadose profile during the recharge process. By applying TFWB procedures for the full soil and vadose zone between the surface to the water table, good estimates of local recharge to the Carrington aquifer could be made for the experimental area using few measurement sites.

Multilevel analysis of variance used to partition components of optical imprecision in an analyser system with disposable cuvettes

Multilevel analysis of variance used to partition components of optical imprecision in an analyser system with disposable cuvettes

Partition components of flicker noise

The flicker noise fluctuations in the space current of a thermionic valve are reduced by operating the valve under space charge limited conditions. In a pentode, this ?smoothing? is less effective due to the division of the current between the anode and the screen grid; consequently, a partition component of flicker noise may be said to occur. Experiments are described which confirm the presence of this phenomenon and which give useful evidence on the origin of the flicker noise. When making measurements on standard valves, there were encountered a number of defects which lead to the generation of excess noise at low frequencies.