Mutually Consistent Research Articles

Consistency of the average flux of solar energetic particles over timescales of years to megayears

Aims. Solar energetic particles (SEPs) have been measured directly in space over the past decades. Rare extreme SEP events are studied based on terrestrial cosmogenic proxy data for the past ten millennia. Lunar rocks record the average SEP fluxes on the megayear timescale. The question of whether the SEP fluxes averaged over different timescales are mutually consistent is still open. Here we analyze these different datasets for mutual consistency. Methods. Using the data from directly measured SEPs over the past decades and reconstructions of extreme SEP events in the past, we built a distribution function of the occurrence of annual SEP fluences for SEPs with energies above 30, 60, 100, and 200 MeV. The distribution function was fit with the Weibull and other types of distributions, and the long-term average SEP flux was computed and compared with the megayear SEP flux estimated from lunar data. Results. In contrast to the current paradigm, the direct space-era data are not representative of the long-term averaged SEP flux because they are only 20–55% of it, while the major fraction was formed by rare extreme SEP events in the past. The combined statistics of direct and proxy data are fully consistent with megayear lunar data, implying that our knowledge of the whole range of the SEP fluxes, from frequent weak to rare extreme events, is now consistent.

CULTURE, POWER AND STRUCTURE OF ORGANIZATION: AN INTEGRATIVE RESEARCH FRAMEWORK

The aim of the paper is to develop an integrative research framework for analyzing the relationships between organizational culture, power, and structure. Organization is observed as a configuration of mutually consistent components, so the main research question emerges: How organizational components impact each other? In this paper, the answer to this question is given through the analysis of the interrelationships between organizational culture, power and structure by applying the metaphor of the hologram. We started from the position that an organization must be understood as a state arising from the processes at both individual and organizational levels. The organization members’ needs for affiliation, power and achievement generate psychosocial, political and functional actions at the individual level, as well as the same processes at the organizational level. These processes generate organizational culture, power and structure as elements of the organization. However, the key idea is that culture, power and structure are derived from the wholeness of organizational processes and therefore contain each other as a kind of hologram. As a result, culture legitimizes power and structure, power instrumentalizes culture and structure, while structure institutionalizes culture and power. The paper shows practical implications of an integrative research framework both through defining further directions for research into relationships between culture, power and structure, as well as through showing to the management of organizations why it is necessary to understand and take into account the mutual consistency between culture, power, and structure.

Note on the dominance rules in the exact algorithm for the container pre-marshalling problem by Tanaka & Tierney (2018)

In this note, we identify an over-pruning issue that occurs in the iterative deepening branch-and-bound algorithm by Tanaka and Tierney (2018). We show that this over-pruning issue is caused by an inconsistency between two dominance rules, namely, the transitive move rule and the empty stack rule, and it will in turn cause the exact algorithm to produce incorrect optimal solutions. To address this issue, we propose a new concept termed the lexicographic dominance principle, and prove that all dominance rules under the lexicographic dominance principle are mutually consistent. Finally, we re-examine all the dominance rules described in the referred paper, and present a compatible set of dominance rules to guarantee mutual consistency.

Testing the mutual consistency of different supernovae surveys

It is now common practice to constrain cosmological parameters using supernovae (SNe) catalogues constructed from several different surveys. Before performing such a joint analysis, however, one should check that parameter constraints derived from the individual SNe surveys that make up the catalogue are mutually consistent. We describe a statistically-robust mutual consistency test, which we calibrate using simulations, and apply it to each pairwise combination of the surveys making up, respectively, the UNION2 catalogue and the very recent JLA compilation by Betoule et al. We find no inconsistencies in the latter case, but conclusive evidence for inconsistency between some survey pairs in the UNION2 catalogue.

Testing the mutual consistency of different supernovae surveys

AbstractIt is now common practice to constrain cosmological parameters using supernovae (SNe) catalogues constructed from several different surveys. Before performing such a joint analysis, however, one should check that parameter constraints derived from the individual SNe surveys that make up the catalogue are mutually consistent. We describe a statistically-robust mutual consistency test, which we calibrate using simulations, and apply it to each pairwise combination of the surveys making up, respectively, the UNION2 catalogue and the very recent JLA compilation by Betoule et al. We find no inconsistencies in the latter case, but conclusive evidence for inconsistency between some survey pairs in the UNION2 catalogue.

Mutually consistent thermodynamic potentials for fluid water, ice and seawater: a new standard for oceanography

Abstract. A new seawater standard for oceanographic and engineering applications has been developed that consists of three independent thermodynamic potential functions, derived from extensive distinct sets of very accurate experimental data. The results have been formulated as Releases of the International Association for the Properties of Water and Steam, IAPWS (1996, 2006, 2008) and are expected to be adopted internationally by other organizations in subsequent years. In order to successfully perform computations such as phase equilibria from combinations of these potential functions, mutual compatibility and consistency of these independent mathematical functions must be ensured. In this article, a brief review of their separate development and ranges of validity is given. We analyse background details on the conditions specified at their reference states, the triple point and the standard ocean state, to ensure the mutual consistency of the different formulations, and the necessity and possibility of numerically evaluating metastable states of liquid water. Computed from this formulation in quadruple precision (128-bit floating point numbers), tables of numerical reference values are provided as anchor points for the consistent incorporation of additional potential functions in the future, and as unambiguous benchmarks to be used in the determination of numerical uncertainty estimates of double-precision implementations on different platforms that may be customized for special purposes.

Observed Inconsistencies between Snow Extent and Snow Depth Variability at Regional/Continental Scales

Abstract Snow extent and snow depth are two related characteristics of a snowpack, but they do not need to be mutually consistent. Differences between these two variables at local scales are readily apparent. However, at larger scales, which interact with atmospheric circulation and climate, snow extent is the primary variable considered, owing largely to the scarcity of snow depth data. In this study, three regional-/continental-scale gridded snow depth/snow water equivalent (SWE) datasets, derived from station observations or passive microwave satellite sensors, are utilized to quantitatively evaluate the relationship between snow extent and snow depth/SWE over North America. Various statistical methods are used to ensure the robustness of the results, including correlations, composites, and singular value decomposition analyses. Results indicate that continental-scale snow depth variations are substantial in their own right and that depth and extent anomalies are largely unrelated over broad high-latitude regions north of the snow line. Snow extent and snow depth vary more consistently in the vicinity of the snow line, especially in autumn and spring, during which precipitation and ablation can affect both variables. It is also found that deeper (shallower) winter snow translates into larger (smaller) snow-covered areas in the following spring/summer season, and also a longer (shorter) snow season, but only in specific regions. These results suggest a possible influence of snow depth on spring and summer climate. Overall, the observed lack of mutual consistency between these two snowpack variables at continental/regional scales suggests that snow depth variations may be of sufficiently large magnitude, spatial scope, and temporal duration to interact with regional–hemispheric climate, in a manner unrelated to the more extensively studied snow extent variations.

Genetic algorithm solution for the stochastic equilibrium transportation networks under congestion

A bi-level and mutually consistent (MC) programming techniques have previously been proposed, in which an area traffic control problem (ATC) is dealt with as upper-level problem whilst the users' equilibrium traffic assignment is dealt with as lower-level problem. In this study, genetic algorithm (GA) approach has been proposed to solve upper-level problem for a signalized road network under congestion. Stochastic user equilibrium (SUE) traffic assignment is applied at the lower-level. At the upper-level, GA provides a feasible set of signal timings within specified lower and upper bounds on signal timing variables and feeds into lower-level problem. The SUE assignment is solved by way of Path Flow Estimator (PFE) and TRANSYT traffic model is applied at upper-level to obtain network performance index (PI) and hence fitness index. Network performance index is defined as the sum of a weighted linear combination of delay and number of stops per unit time under various levels of traffic loads. For this purpose, the genetic optimizer, referred to as GATRANSPFE, combines the TRANSYT model, used to estimate performance, with the PFE logit assignment tool, used to predict traffic reassignment, is developed. The GATRANSPFE that can solve the ATC and SUE traffic assignment problem has been applied to the signalized road networks under congestion. The effectiveness of the GATRANSPFE over the MC method has been investigated in terms of good values of network performance index and convergence. Comparisons of the performance index resulting from the GATRANSPFE and that of mutually consistent TRANSYT-optimal signal settings and SUE traffic flows are made.

Traffic signal timing optimisation based on genetic algorithm approach, including drivers’ routing

The genetic algorithm approach to solve traffic signal control and traffic assignment problem is used to tackle the optimisation of signal timings with stochastic user equilibrium link flows. Signal timing is defined by the common network cycle time, the green time for each signal stage, and the offsets between the junctions. The system performance index is defined as the sum of a weighted linear combination of delay and number of stops per unit time for all traffic streams, which is evaluated by the traffic model of TRANSYT [User guide to TRANSYT, version 8, TRRL Report LR888, Transport and Road Research Laboratory, Crowthorne, 1980]. Stochastic user equilibrium assignment is formulated as an equivalent minimisation problem and solved by way of the Path Flow Estimator (PFE). The objective function adopted is the network performance index (PI) and its use for the Genetic Algorithm (GA) is the inversion of the network PI, called the fitness function. By integrating the genetic algorithms, traffic assignment and traffic control, the GATRANSPFE (Genetic Algorithm, TRANSYT and the PFE), solves the equilibrium network design problem. The performance of the GATRANSPFE is illustrated and compared with mutually consistent (MC) solution using numerical example. The computation results show that the GA approach is efficient and much simpler than previous heuristic algorithm. Furthermore, results from the test road network have shown that the values of the performance index were significantly improved relative to the MC.

GUARANTEED MUTUALLY CONSISTENT CHECKPOINTING IN DISTRIBUTED COMPUTATIONS

In this paper, we explore the isomorphism between vector time and causality to characterize consistency of a set of checkpoints in a distributed computing. A necessary and sufficient condition, to determine if a set of local checkpoints can form a consistent global checkpoint, is presented and proved using the isomorphic power of vector time and causality. To the best of our knowledge, this is the first attempt to use the isomorphism for this purpose. This condition leads to a simple and straightforward algorithm for a guaranteed mutually consistent global checkpointing. In our approach, a process can take a checkpoint whenever and wherever it wants while other related process may be asked to take an additional checkpoint for ensuring the mutual consistency. We also show how this condition and the resulting algorithm can be used to obtain a maximum and minimum global checkpoints, another important paradigm for distributed applications.

Efficient concurrency control for broadcast environments

A crucial consideration in environments where data is broadcast to clients is the low bandwidth available for clients to communicate with servers. Advanced applications in such environments do need to read data that is mutually consistent as well as current. However, given the asymmetric communication capabilities and the needs of clients in mobile environments, traditional serializability-based approaches are too restrictive, unnecessary, and impractical. We thus propose the use of a weaker correctness criterion called update consistency and outline mechanisms based on this criterion that ensure (1) the mutual consistency of data maintained by the server and read by clients, and (2) the currency of data read by clients. Using these mechanisms, clients can obtain data that is current and mutually consistent “off the air”, i.e., without contacting the server to, say, obtain locks. Experimental results show a substantial reduction in response times as compared to existing (serializability-based) approaches. A further attractive feature of the approach is that if caching is possible at a client, weaker forms of currency can be obtained while still satisfying the mutual consistency of data.

Infrared radiation models for atmospheric methane

Mutually consistent line‐by‐line, narrow‐band and broad‐band infrared radiation models are presented for methane, a potentially important anthropogenic trace gas within the atmosphere. Comparisons of the modeled band absorptances with existing laboratory data produce the best agreement when, within the band models, spurious band intensities are used which are consistent with the respective laboratory data sets, but which are not consistent with current knowledge concerning the intensity of the infrared fundamental band of methane. This emphasizes the need for improved laboratory band absorptance measurements. Since, when applied to atmospheric radiation calculations, the line‐by‐line model does not require the use of scaling approximations, the mutual consistency of the band models provides a means of appraising the accuracy of scaling procedures. It is shown that Curtis‐Godson narrow‐band and Chan‐Tien broad‐band scaling provide accurate means of accounting for atmospheric temperature and pressure variations.

A method of interpolating magnetic data under conditions of mutual consistency

Because of the discreteness of the data obtained in magnetic surveys, it is necessary to interpolate between measured points before charts can be drawn. Rigorous relations connecting surface variations of different elements are herein introduced into the interpolation formulas, so that the resulting charts are mutually consistent. Related elements are continued by a power series in which the unknown coefficients are computed under the conditions for consistency.

Note on the adjustment of isomagnetic charts to mutual consistency

Precise aeromagnetic measurements of total magnetic intensity permit the construction of isomagnetic charts which are mutually consistent in the horizontal and vertical components of the geomagnetic fields. Equations incorporating this new result are provided.