Showing papers by "University of Waterloo published in 2004"
TL;DR: In the presence of salt the bacterium increased the water use efficiency (WUE), which may suggest that the bacteriod act to alleviate the salt suppression of photosynthesis, however, the detailed mechanism was not elucidated.
1,119 citations
TL;DR: Developments from the understanding of the complex protein translocation machinery of Gram-positive bacteria should allow the resolution of current secretion challenges and make Bacillus species preeminent hosts for heterologous protein production.
Abstract: Bacillus species continue to be dominant bacterial workhorses in microbial fermentations. Bacillus subtilis (natto) is the key microbial participant in the ongoing production of the soya-based trad...
1,100 citations
TL;DR: The demonstration of non-carbonaceous-network grain-boundary conduction to be the first in these materials, and that it holds promise for other insulating phosphates.
Abstract: The provision of efficient electron and ion transport is a critical issue in an exciting new group of materials based on lithium metal phosphates that are important as cathodes for lithium-ion batteries. Much interest centres on olivine-type LiFePO(4), the most prominent member of this family. Whereas the one-dimensional lithium-ion mobility in this framework is high, the electronically insulating phosphate groups that benefit the voltage also isolate the redox centres within the lattice. The pristine compound is a very poor conductor (sigma approximately 10(-9) S cm(-1)), thus limiting its electrochemical response. One approach to overcome this is to include conductive phases, increasing its capacity to near-theoretical values. There have also been attempts to alter the inherent conductivity of the lattice by doping it with a supervalent ion. Compositions were reported to be black p-type semiconductors with conductivities of approximately 10(-2) S cm(-1) arising from minority Fe(3+) hole carriers. Our results for doped (and undoped) LiMPO(4) (M = Fe, Ni) show that a percolating nano-network of metal-rich phosphides are responsible for the enhanced conductivity. We believe our demonstration of non-carbonaceous-network grain-boundary conduction to be the first in these materials, and that it holds promise for other insulating phosphates.
1,008 citations
TL;DR: In this paper, the authors proposed a new normalized information distance based on the non-computable notion of Kolmogorov complexity, which minorizes every computable distance in the class (that is, it is universal in that it discovers all computable similarities).
Abstract: A new class of distances appropriate for measuring similarity relations between sequences, say one type of similarity per distance, is studied. We propose a new "normalized information distance," based on the noncomputable notion of Kolmogorov complexity, and show that it is in this class and it minorizes every computable distance in the class (that is, it is universal in that it discovers all computable similarities). We demonstrate that it is a metric and call it the similarity metric . This theory forms the foundation for a new practical tool. To evidence generality and robustness, we give two distinctive applications in widely divergent areas using standard compression programs like gzip and GenCompress. First, we compare whole mitochondrial genomes and infer their evolutionary history. This results in a first completely automatic computed whole mitochondrial phylogeny tree. Secondly, we fully automatically compute the language tree of 52 different languages.
1,002 citations
TL;DR: In this article, the authors introduce a survey of this revolutionary approach of DGs, which will change the way electric power systems operate along with their types and operating technologies, and survey the operational and economical benefits of implementing DGs in the distribution network.
966 citations
TL;DR: The progress to date in using PGPR in a variety of applications with different plants is summarized and discussed here.
Abstract: Free-living plant growth-promoting rhizobacteria (PGPR) can be used in a variety of ways when plant growth enhancements are required. The most intensively researched use of PGPR has been in agriculture and horticulture. Several PGPR formulations are currently available as commercial products for agricultural production. Recently developing areas of PGPR usage include forest regeneration and phytoremediation of contaminated soils. As the mechanisms of plant growth promotion by these bacteria are unravelled, the possibility of more efficient plant-bacteria pairings for novel and practical uses will follow. The progress to date in using PGPR in a variety of applications with different plants is summarized and discussed here.
958 citations
TL;DR: Based on the results of the experiments reported herein, the use of plant growth-promoting bacteria such as A. piechaudii ARV8 may provide a means of facilitating plant growth in arid environments.
834 citations
31 Aug 2004
TL;DR: A new distance function, which is a marriage of L1- norm and the edit distance, ERP, which can support local time shifting, and is a metric, and dominates all existing strategies.
Abstract: Existing studies on time series are based on two categories of distance functions. The first category consists of the Lp-norms. They are metric distance functions but cannot support local time shifting. The second category consists of distance functions which are capable of handling local time shifting but are nonmetric. The first contribution of this paper is the proposal of a new distance function, which we call ERP ("Edit distance with Real Penalty"). Representing a marriage of L1- norm and the edit distance, ERP can support local time shifting, and is a metric.
The second contribution of the paper is the development of pruning strategies for large time series databases. Given that ERP is a metric, one way to prune is to apply the triangle inequality. Another way to prune is to develop a lower bound on the ERP distance. We propose such a lower bound, which has the nice computational property that it can be efficiently indexed with a standard B+- tree. Moreover, we show that these two ways of pruning can be used simultaneously for ERP distances. Specifically, the false positives obtained from the B+-tree can be further minimized by applying the triangle inequality. Based on extensive experimentation with existing benchmarks and techniques, we show that this combination delivers superb pruning power and search time performance, and dominates all existing strategies.
790 citations
TL;DR: In this article, the color distribution of 24,346 galaxies drawn from the Sloan Digital Sky Survey first data release, as a function of luminosity and environment, was analyzed and a weakly significant (3 σ) detection of a trend for colors to become redder by 0.1-0.14 was made, with a factor of ~100 increase in local density, as characterized by the surface density of galaxies within a ±1000 km s-1 redshift slice.
Abstract: We analyze the u - r color distribution of 24,346 galaxies with Mr ≤ -18 and z < 0.08, drawn from the Sloan Digital Sky Survey first data release, as a function of luminosity and environment. The color distribution is well fitted with two Gaussian distributions, which we use to divide the sample into a blue and red population. At fixed luminosity, the mean color of the blue (red) distribution is nearly independent of environment, with a weakly significant (~3 σ) detection of a trend for colors to become redder by 0.1-0.14 (0.03-0.06) mag with a factor of ~100 increase in local density, as characterized by the surface density of galaxies within a ±1000 km s-1 redshift slice. In contrast, at fixed luminosity the fraction of galaxies in the red distribution is a strong function of local density, increasing from ~10%-30% of the population in the lowest density environments to ~70% at the highest densities. The strength of this trend is similar for both the brightest (-23 < Mr < -22) and faintest (-19 < Mr < -18) galaxies in our sample. The fraction of red galaxies within the virialized regions of clusters shows no significant dependence on velocity dispersion. Even at the lowest densities explored, a substantial population of red galaxies exists, which might be fossil groups. We propose that most star-forming galaxies today evolve at a rate that is determined primarily by their intrinsic properties and independent of their environment. Any environmentally triggered transformations from blue to red colors must occur either on a short timescale or preferentially at high redshift to preserve the simple Gaussian nature of the color distribution. The mechanism must be effective for both bright and faint galaxies.
669 citations
TL;DR: Meta-analytic findings indicate that Neuroticism, Extraversion, Agreeableness, and Conscientiousness are related to both various domain satisfactions and life satisfaction; however, consistent with a bottom-up approach, domain satisf actions are strongly linked to life satisfaction but only weakly linked to each other.
Abstract: Two main theoretical approaches have been put forward to explain individual differences in life satisfaction: top-down (i.e., personological) and bottom-up (i.e., situational). The authors examine the relative merit of these 2 approaches and the psychological processes underlying top-down models. Consistent with a top-down approach, meta-analytic findings indicate that Neuroticism, Extraversion, Agreeableness, and Conscientiousness are related to both various domain satisfactions and life satisfaction; however, consistent with a bottom-up approach, domain satisfactions are strongly linked to life satisfaction but only weakly linked to each other. Path analyses based on meta-analytic estimates did not support a simple "direct-effects" top-down model but supported both (a) a temperament-based top-down model and (b) an integrative model that incorporates the direct influence of domain satisfactions on life satisfaction.
TL;DR: In this article, a holographic version of the Vafa-Witten theorem was shown to hold for non-supersymmetric, four-dimensional QCDs with N c colours and N f 0, obeying the Gell-Mann-Oakes-Renner relation.
Abstract: We study N f D6-brane probes in the supergravity background dual to N c D4-branes compactified on a circle with supersymmetry-breaking boundary conditions. In the limit in which the resulting Kaluza-Klein modes decouple, the gauge theory reduces to non-supersymmetric, four-dimensional QCD with N c colours and N f 0, obeying the Gell-Mann-Oakes-Renner relation: M π 2 = −m q ψ/fπ2 . In the case 1$> N f>1 we provide a holographic version of the Vafa-Witten theorem, which states that the U(N f) flavour symmetry cannot be spontaneously broken. Further, we find N f 2−1 unexpectedly light pseudo-scalar mesons in the spectrum. We argue that these are not (pseudo-)Goldstone bosons and speculate on the string mechanism responsible for their lightness. We then study the theory at finite temperature and exhibit a phase transition associated with a discontinuity in ψ(T). D6/ pairs are also briefly discussed.
26 Feb 2004
TL;DR: This chapter discusses the nature of resistance in Persuasion, the role of belief and meta-Beliefs, and strategies for overcoming resistance.
Abstract: Contents: Foreword. Part I: Introduction. E.S. Knowles, J.A. Linn, The Importance of Resistance to Persuasion. Part II: Nature of Resistance in Persuasion. D.T. Wegener, R.E. Petty, N.D. Smoak, L.R. Fabrigar, Multiple Routes to Resisting Attitude Change. K. Fuegen, J.W. Brehm, The Intensity of Affect and Resistance to Social Influence. Z.L. Tormala, R.E. Petty, Resisting Persuasion and Attitude Certainty: A Meta-Cognitive Analysis. P. Brinol, D.D. Rucker, Z.L. Tormala, R.E. Petty, Individual Differences in Resistance to Persuasion: The Role of Beliefs and Meta-Beliefs. R.J. Shakarchi, C.P. Haugtvedt, Differentiating Individual Differences in Resistance to Persuasion. Part III: Strategies for Overcoming Resistance. E.S. Knowles, J.A. Linn, Approach-Avoidance Model of Persuasion: Alpha and Omega Strategies for Change. S.J. Sherman, M.T. Crawford, A.R. McConnell, Looking Ahead as a Technique to Reduce Resistance to Persuasive Attempts. S. Dal Cin, M.P. Zanna, G.T. Fong, Narrative Persuasion and Overcoming Resistance. J.M. Quinn, W. Wood, Forewarnings of Influence Appeals: Inducing Resistance and Acceptance. B.T. Johnson, A. Smith-McLallen, L.A. Killeya, K.D. Levin, Truth or Consequences: Overcoming Resistance to Persuasion With Positive Thinking. J.Z. Jacks, M.E. O'Brien, Decreasing Resistance by Affirming the Self. B.J. Sagarin, R.B. Cialdini, Creating Critical Consumers: Motivating Receptivity by Teaching Resistance. C.P. Haugtvedt, R.J. Shakarchi, B.M. Samuelsen, K. Liu, Consumer Psychology and Attitude Change. Part IV: Conclusion. E.S. Knowles, J.A. Linn, The Promise and Future of Resistance and Persuasion.
TL;DR: In this article, a new heuristic approach for distributed generation (DG) capacity investment planning from the perspective of a distribution company (disco) is obtained through a cost-benefit analysis approach based on a new optimization model.
Abstract: This paper proposes a new heuristic approach for distributed generation (DG) capacity investment planning from the perspective of a distribution company (disco). Optimal sizing and siting decisions for DG capacity is obtained through a cost-benefit analysis approach based on a new optimization model. The model aims to minimize the disco's investment and operating costs as well as payment toward loss compensation. Bus-wise cost-benefit analysis is carried out on an hourly basis for different forecasted peak demand and market price scenarios. This approach arrives at the optimal feasible DG capacity investment plan under competitive electricity market auction as well as fixed bilateral contract scenarios. The proposed heuristic method helps alleviate the use of binary variables in the optimization model thus easing the computational burden substantially.
TL;DR: A tractable gamma-process model incorporating a random effect is constructed fitted to some data on crack growth and corresponding goodness-of-fit tests are carried out and prediction calculations for failure times defined in terms of degradation level passages are developed and illustrated.
Abstract: The gamma process is a natural model for degradation processes in which deterioration is supposed to take place gradually over time in a sequence of tiny increments. When units or individuals are observed over time it is often apparent that they degrade at different rates, even though no differences in treatment or environment are present. Thus, in applying gamma-process models to such data, it is necessary to allow for such unexplained differences. In the present paper this is accomplished by constructing a tractable gamma-process model incorporating a random effect. The model is fitted to some data on crack growth and corresponding goodness-of-fit tests are carried out. Prediction calculations for failure times defined in terms of degradation level passages are developed and illustrated.
Proceedings Article•
01 Dec 2004TL;DR: A new method for clustering based on finding maximum margin hyperplanes through data that leads naturally to a semi-supervised training method for support vector machines by maximizing the margin simultaneously on labeled and unlabeled training data.
Abstract: We propose a new method for clustering based on finding maximum margin hyperplanes through data. By reformulating the problem in terms of the implied equivalence relation matrix, we can pose the problem as a convex integer program. Although this still yields a difficult computational problem, the hard-clustering constraints can be relaxed to a soft-clustering formulation which can be feasibly solved with a semidefinite program. Since our clustering technique only depends on the data through the kernel matrix, we can easily achieve nonlinear clusterings in the same manner as spectral clustering. Experimental results show that our maximum margin clustering technique often obtains more accurate results than conventional clustering methods. The real benefit of our approach, however, is that it leads naturally to a semi-supervised training method for support vector machines. By maximizing the margin simultaneously on labeled and unlabeled training data, we achieve state of the art performance by using a single, integrated learning principle.
TL;DR: In this article, the conditions under which metastable strings can exist were investigated, and it was shown that such strings are present in many models, including a network of (p, q) strings.
Abstract: Macroscopic fundamental and Dirichlet strings have several potential instabilities: breakage, tachyon decays, and confinement by axion domain walls. We investigate the conditions under which metastable strings can exist, and we find that such strings are present in many models. There are various possibilities, the most notable being a network of (p,q) strings. Cosmic strings give a potentially large window into string physics.
30 Aug 2004
TL;DR: In this paper, the authors propose a cardinality-based notation for feature modeling, which integrates a number of existing extensions of previous approaches, and then introduce and motivate the novel concept of staged configuration.
Abstract: Feature modeling is an important approach to capturing commonalities and variabilities in system families and product lines. In this paper, we propose a cardinality-based notation for feature modeling, which integrates a number of existing extensions of previous approaches. We then introduce and motivate the novel concept of staged configuration. Staged configuration can be achieved by the stepwise specialization of feature models. This is important because in a realistic development process, different groups and different people eliminate product variability in different stages. We also indicate how cardinality-based feature models and their specialization can be given a precise formal semantics.
TL;DR: Genes encoding dual-function plant antifreeze proteins are excellent models for use in evolutionary studies to determine how genes acquire new expression patterns and how proteins acquire new activities.
Book•
25 Jun 2004TL;DR: This book discusses how to develop a Work Domain Model for EID and some of the techniques used to develop such a model include:.
Abstract: Introduction and Overview Scope of this Book Types of Design Problems The Ecological Part of EID Outline Motivation for EID History Work Domain Analysis Defining the System of Interest What Is an Abstraction Hierarchy? Level by Level, Working through an Abstraction Hierarchy Part-Whole Hierarchies Models with Social Constraints Techniques for Managing Large Models Models of Multiple Domains Testing Your Model for Completeness Summary: Double-Checking Your Work Domain Model - Rules to Use as You Actually Build It The Language of Interface Design Interface Description Forms of Reference A Visual Thesaurus for Data Relationships How to Develop a New Visual Form Summary: Visual Thesaurus Review Sheet Using a Work Domain Model in Design Information Requirements Information Availability Analysis: What to Do if You Can't Measure It Using Information Requirements in Design Example Design Process Functional Information Profiles: Working with Existing Designs Summary: From Information and Constraints to Design Transportation Systems Challenges with Transportation Systems Analysis for Command and Control of a Frigate Analysis for Command and Control of a Destroyer A Display for an Aircraft A Display for Balancing Fuel in an Aircraft Handling the Challenges Process Control Systems Challenges with Process Control Systems Design for Thermal Power Generation System Design for a Nuclear Power Simulation Design for a Pasteurizer Design for an Acetylene Hydrogenation Reactor Design for a Large Refinery Handling the Challenges Telecommunications Systems Challenges with Telecommunications Systems Analysis for Network Management An Alternative Design: Design for Scalability Analysis for Radio Communications Handling the Challenges Medical Systems Challenges Design for Oxygenation Monitoring in the Neonatal Intensive Care Unit Patient Monitoring in the Operating Room Analysis for Diabetes Management Handling the Challenges Social Systems Challenges Casino Gambling Handling the Challenges Using EID with Other Methods A Design Framework: Defining Opportunities to Use EID with Other Methods EID and Other Methods Summary Conclusion References Index
TL;DR: In this paper, the authors describe two recent cases from British Columbia, Canada, where rockslides entrained substrate on a very large scale, influencing the character of the events.
Abstract: Many rock avalanches entrain and liquefy saturated soil from their paths. Evidence for this includes mud displaced from the margins of rock avalanche deposits, substrate material smeared along the base of deposits, extrusion of liquefied soil upward through the deposits, and increases of volume. A hypothesis first suggested in 1881 and since reinforced by several authors suggests that entrainment of substrate material increases mobility. Although the process has been discussed in the literature for more than 100 years, few detailed and quantitative descriptions exist. The main purpose of this paper is to describe two recent cases from British Columbia, Canada, where rockslides entrained substrate on a very large scale, influencing the character of the events. Estimated volume balance curves, based on detailed field mapping, are provided for both cases. Dynamic analyses are carried out using a numerical model and using the same set of rheological parameters. The mechanism of material entrainment and displacement is discussed. The data suggest that rapid rock failures entraining very large quantities of saturated substrate material represent a special type of landslide, transitional between rock avalanche and debris avalanche. Many rock avalanches can thus be seen as end members of a continuum of phenomena involving rock failure followed by interaction with saturated substrate.
TL;DR: A new and simple empirical method was used to relate fluxes obtained from minipiezometer data to streambed temperatures and a conceptual model for ground water/surface water interactions consisting of five different behaviors was developed based on the magnitude and direction of flux across the surface of the streambed.
Abstract: Streambed temperature mapping, hydraulic testing using minipiezometers, and geochemical analyses of interstitial water of the streambed were used to delineate the pattern of ground water discharge in a sandy streambed and to develop a flux-based conceptual model for ground water/surface water interactions. A new and simple empirical method was used to relate fluxes obtained from minipiezometer data to streambed temperatures. The relationship allowed flux to be calculated at locations where only streambed temperature measurements were made. Slug testing and potentiomanometer measurements at 34 piezometers indicated ground water discharge ranged from 0.03 to 446 L/m2/day (and possibly as high as 7060 L/m2/day) along a 60 m long by 11 to 14 m wide reach of river. Complex but similar plan-view patterns of flux were calculated for both summer and winter using hundreds of streambed temperatures measured on a 1 by 2 m grid. The reach was dominated by ground water discharge and 5% to 7% of the area accounted for ∼20% to 24% of the total discharge. < 12% of the total area consisted of recharge zones or no-discharge zones. A conceptual model for ground water/surface water interactions consisting of five different behaviors was developed based on the magnitude and direction of flux across the surface of the streambed. The behaviors include short-circuit discharge (e.g., high-flow springs), high discharge (e.g., preferential flowpaths), low to moderate discharge, no discharge (e.g., horizontal hyporheic or ground water flow), and recharge. Geological variations at depth played a key role in determining which type of flow behavior occurred in the streambed.
01 Sep 2004
TL;DR: A new rank-join algorithm that makes use of the individual orders of its inputs to produce join results ordered on a user-specified scoring function is introduced and implemented inside a prototype database engine based on PREDATOR.
Abstract: Ranking queries, also known as top-k queries, produce results that are ordered on some computed score. Typically, these queries involve joins, where users are usually interested only in the top-k join results. Top-k queries are dominant in many emerging applications, e.g., multimedia retrieval by content, Web databases, data mining, middlewares, and most information retrieval applications. Current relational query processors do not handle ranking queries efficiently, especially when joins are involved. In this paper, we address supporting top-k join queries in relational query processors. We introduce a new rank-join algorithm that makes use of the individual orders of its inputs to produce join results ordered on a user-specified scoring function. The idea is to rank the join results progressively during the join operation. We introduce two physical query operators based on variants of ripple join that implement the rank-join algorithm. The operators are nonblocking and can be integrated into pipelined execution plans. We also propose an efficient heuristic designed to optimize a top-k join query by choosing the best join order. We address several practical issues and optimization heuristics to integrate the new join operators in practical query processors. We implement the new operators inside a prototype database engine based on PREDATOR. The experimental evaluation of our approach compares recent algorithms for joining ranked inputs and shows superior performance.
TL;DR: The use of plant species that have the ability to proliferate in the presence of high levels of contaminants and strains of PGPR that increase plant tolerance to contaminants and accelerate plant growth in heavily contaminated soils resulted in rapid and massive biomass accumulation of plant tissue in contaminated soil.
TL;DR: Despite the recent proliferation of leisure involvement and loyalty research, very little attention has been given to systematically conceptualize and examine the nature of the leisure involvement's re-engagement.
Abstract: Despite the recent proliferation of leisure involvement and loyalty research, very little attention has been given to systematically conceptualize and examine the nature of leisure involvement's re...
TL;DR: This article proposed a phrase-based document index model, the document index graph, which allows for incremental construction of a phrasebased index of the document set with an emphasis on efficiency, rather than relying on single-term indexes only.
Abstract: Document clustering techniques mostly rely on single term analysis of the document data set, such as the vector space model. To achieve more accurate document clustering, more informative features including phrases and their weights are particularly important in such scenarios. Document clustering is particularly useful in many applications such as automatic categorization of documents, grouping search engine results, building a taxonomy of documents, and others. This article presents two key parts of successful document clustering. The first part is a novel phrase-based document index model, the document index graph, which allows for incremental construction of a phrase-based index of the document set with an emphasis on efficiency, rather than relying on single-term indexes only. It provides efficient phrase matching that is used to judge the similarity between documents. The model is flexible in that it could revert to a compact representation of the vector space model if we choose not to index phrases. The second part is an incremental document clustering algorithm based on maximizing the tightness of clusters by carefully watching the pair-wise document similarity distribution inside clusters. The combination of these two components creates an underlying model for robust and accurate document similarity calculation that leads to much improved results in Web document clustering over traditional methods.
TL;DR: In this paper, the performance of recurrent neural networks (RNNs) and neuro-fuzzy (NF) predictors is evaluated using two benchmark data sets and it is found that if an NF system is properly trained, it performs better than RNNs in both forecasting accuracy and training efficiency.
TL;DR: The data support and extend the use of an inverted pendulum model to represent quiet standing postural control and how well the individual segments and lower limb angles temporally and spatially synchronize with the total body center of mass.
TL;DR: The FSP is a practical intervention that elicits an immediate and profound change in walking behaviour that is an important ‘first step’ towards increasing the volume and/or intensity of PA necessary to improve long-term health outcomes in this largely sedentary and overweight or obese population.
Abstract: OBJECTIVE: To conduct a randomised trial of a physical activity (PA) intervention, The First Step Program (FSP) for adults with type II diabetes. DESIGN: A 16-week intervention study and 24-week follow-up assessment. PARTICIPANTS: A total of 47 overweight/obese, sedentary individuals (age=52.7±5.2 y; BMI=33.3±5.6 kg/m2) recruited through a diabetes education centre. MEASUREMENTS: Primary outcome: daily PA assessed by pedometer (steps/day). Secondary outcomes: anthropometric measures (weight, BMI, waist girth, hip girth); indicators of cardiovascular health (resting heart rate and blood pressure); glycemic control (fasting glucose, insulin, HbA1c, glucose concentration 120 min postglucose load); plasma lipid status (total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides). RESULTS: Relative to the CONTROL group, FSP participants increased their PA >3000 steps/day (approximately 30 min/day) during the intervention (P<0.0001). Waist and hip girth decreased (approximately 2–3 cm), but did not differ significantly between groups. Significant changes did not emerge for any of the other variables. CONCLUSIONS: The FSP is a practical intervention that elicits an immediate and profound change in walking behaviour. Such change is an important ‘first step’ towards increasing the volume and/or intensity of PA necessary to improve long-term health outcomes in this largely sedentary and overweight or obese population. Relapse by 24 weeks indicates that other strategies such as booster sessions are needed to maintain lifestyle change. Further research must determine realistic and responsive health outcomes for this population that are achievable through practical, real-world programming.
TL;DR: The authors argue that the word counterurbanization is too broad to cover its depth of meaning and propose adoption of three concepts to describe the changing spatial redistribution of population: counterurban, counterurbanizing, and counterurbanisation.