scholarly journals ON THE TECHNIQUE OF MODELING ONTOGENETIC CHANGES IN FISH AND INSECTS LIFECYCLE

2017 ◽  
pp. 12-23 ◽  
Author(s):  
A. Yu. Perevaryukha
Keyword(s):  
Nonlinear Effects ◽  
Individual Development ◽  
Ontogenetic Changes ◽  
The Caspian Sea ◽  
Stage Of Development ◽  
Proposed Model ◽  
Long Term Trends ◽  
The Impact ◽  
Computing Structure

The article discusses the approach to modeling of metamorphoses in the development of a number of species in the context of their influence on the success of long-term trends of population dynamics. Changes in survival during early ontogenesis, controlled by important factor – the rate of individual development in a competing group of individuals, can cause unexpected degradation of population with a small excess fishing impact. The theory of nonlinear efficiency of reproduction leads us to the hypothesis that two different nonlinear effects are controlled by similar mechanisms. For insects such fluctuations in survival during metamorphosis can start another process - the rapid outbreak of pests, where actual formalization of the impact of parasites on the first stage of development, depending on the initial concentration of clutches, but limited resources is taken into account at a finishing. The method has been for submission to decline of generations on the basis of dynamic overriding differential equations with discrete-continuous structure of time. To extend the previously proposed model for the formation of generations is formed computing structure for the account mortality depending on the level of competition, complete with trigger functional and a new scheme describing the changes the growth rate for the example of the Caspian Sea sturgeon in three ecological and physiological stages of development. The new model has a non-trivial possibilities parametrically modification of behavior regimes. The coexistence of alternative cycles is explained by the increase in adaptive interspecies differences.

The impact of non-ideality on reconstructing spatial and temporal variations of aerosol acidity with multiphase buffer theory

2021 ◽  
Author(s):  
Yafang Cheng ◽  
Guangjie Zheng ◽  
Hang Su ◽  
Siwen Wang ◽  
Andrea Pozzer
Keyword(s):  
Molar Fraction ◽  
Temporal Variations ◽  
Spatial Variations ◽  
Acid Dissociation ◽  
Acid Dissociation Constant ◽  
Aerosol Acidity ◽  
Long Term Trends ◽  
Factor C ◽  
The Impact

<p>Aerosol acidity is a key parameter in atmospheric aqueous chemistry and strongly influence the interactions of air pollutants and ecosystem. The recently proposed multiphase buffer theory provides a framework to reconstruct long-term trends and spatial variations of aerosol pH based on the effective acid dissociation constant of ammonia (K<sub>a,NH3</sub><sup>*</sup>). However, non-ideality in aerosol droplets is a major challenge limiting its broad applications. Here, we introduced a non-ideality correction factor (c<sub>ni</sub>) and investigated its governing factors. We found that besides relative humidity (RH) and temperature, c<sub>ni</sub> is mainly determined by the molar fraction of NO<sub>3</sub><sup>-</sup> in aqueous-phase anions, due to different NH<sub>4</sub><sup>+</sup> activity coefficients between (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>- and NH<sub>4</sub>NO<sub>3</sub>-dominated aerosols. A parameterization method is thus proposed to estimate c<sub>ni</sub> at given RH, temperature and NO<sub>3</sub><sup>-</sup> fraction, and is validated against long-term observations and global simulations. In the ammonia-buffered regime, with c<sub>ni</sub> correction the buffer theory can well reproduce the K<sub>a,NH3</sub><sup>*</sup> predicted by comprehensive thermodynamic models, with root-mean-square deviation ~0.1 and correlation coefficient ~1. Note that, while c<sub>ni</sub> is needed to predict K<sub>a,NH3</sub><sup>*</sup> levels, it is usually not the dominant contributor to its variations, as ~90% of the temporal or spatial variations in K<sub>a,NH3</sub><sup>*</sup> is due to variations in aerosol water and temperature.</p>

Competition intensity as moderator for NPD success

2019 ◽  
Vol 11 (4) ◽  
pp. 618-647
Author(s):  
Tor Guimaraes ◽  
Ketan Paranjape
Keyword(s):  
New Product Development ◽  
Success Factors ◽  
Multivariate Regression Analysis ◽  
Manufacturing Companies ◽  
Competition Intensity ◽  
Content Type ◽  
Intense Competition ◽  
Proposed Model ◽  
The Impact

Purpose This study aims to test the moderating impact of competition intensity on the relationships between the new product development (NPD) success factors and company success in NPD. Design/methodology/approach A mailed questionnaire collected information from 311 manufacturing companies to test the proposed model with moderated multivariate regression analysis. Findings The results corroborate the impact of competition intensity on the relationships between the success factors individually and company success performing NPD. Research limitations/implications Despite the relatively broad scope of the proposed model, other success factors and/or moderating and mediating variables may also be important. As such, these variables should be identified and tested in future studies. Practical implications In practice, competition is viewed as an unavoidable factor beyond the control of managers within a company. Undeniably, competition is a great stimulant for business innovation. Thus, it is important for managers to understand the need, to focus attention managing the success factors most important to increase the likelihood of long-term success for NPD projects, particularly in markets under intense competition. Originality/value While the study is grounded on well-established literature, its major constructs originated from relatively isolated areas of knowledge. The major contribution is empirically testing an integrated model for variables considered important for success in NPD and the moderating effect of intense competition.

Evaluating the impact of ballast undercutting on the roughness of track geometry over different subgrade conditions

2017 ◽  
Vol 232 (5) ◽  
pp. 1266-1276
Author(s):  
Kirk M Scanlan ◽  
Michael T Hendry ◽  
C Derek Martin
Keyword(s):  
Surface Roughness ◽  
Organic Soils ◽  
Western Canada ◽  
Railway Ballast ◽  
Track Geometry ◽  
Track Maintenance ◽  
Heavy Haul ◽  
Long Term Trends ◽  
The Impact

The progressive degradation of railway ballast is often cited as a primary factor that contributes to the development of track roughness, while ballast renewal (undercutting) attempts to manage its long-term development. Soft subgrades have been shown to strongly influence track geometry and are a contributing factor that has not been considered during conventional track maintenance. This study evaluated the impact of undercutting on long-term trends in track geometry roughness, and what impact softer subgrades had on the effectiveness of undercutting. A combined 6.90 km of Class II–IV heavy-haul track in Western Canada (undercut in 2010 and 2011) formed the basis for this analysis. Annual traffic on these sections typically totals 50 million gross tonnes. Long-term trends in the track crosslevel, alignment, and surface roughness after ballast renewal were derived from 50 track geometry surveys carried out over a five-year period (2010–2015). The results showed that undercutting significantly reduced track roughness over sand, silt, clay, or till subgrades; however, it was often ineffective when used over soft organic subgrades. Thus, while ballast degradation is the primary cause of track roughness in segments constructed on mineral subgrades, it is not a mechanism that results in track geometry roughness over soft organic soils.

scholarly journals The Impact of Improved Thermistor Calibration on the Expendable Bathythermograph Profile Data

2017 ◽  
Vol 34 (9) ◽  
pp. 1947-1961 ◽  
Author(s):  
Marlos Goes ◽  
Elizabeth Babcock ◽  
Francis Bringas ◽  
Peter Ortner ◽  
Gustavo Goni
Keyword(s):  
Small Sample Size ◽  
Heat Content ◽  
Small Sample ◽  
Profile Data ◽  
Expendable Bathythermograph ◽  
Different Types ◽  
Long Term Trends ◽  
The Mean ◽  
The Impact

AbstractExpendable bathythermograph (XBT) data provide one of the longest available records of upper-ocean temperature. However, temperature and depth biases in XBT data adversely affect estimates of long-term trends of ocean heat content and, to a lesser extent, estimates of volume and heat transport in the ocean. Several corrections have been proposed to overcome historical biases in XBT data, which rely on constantly monitoring these biases. This paper provides an analysis of data collected during three recent hydrographic cruises that utilized different types of probes, and examines methods to reduce temperature and depth biases by improving the thermistor calibration and reducing the mass variability of the XBT probes.The results obtained show that the use of individual thermistor calibration in XBT probes is the most effective calibration to decrease the thermal bias, improving the mean thermal bias to less than 0.02°C and its tolerance from 0.1° to 0.03°C. The temperature variance of probes with screened thermistors is significantly reduced by approximately 60% in comparison to standard probes. On the other hand, probes with a tighter weight tolerance did not show statistically significant reductions in the spread of depth biases, possibly because of the small sample size or the sensitivity of the depth accuracy to other causes affecting the analysis.

scholarly journals The Impact of Non-uniform Sampling on Stratospheric Ozone Trends Derived from Occultation Instruments

2017 ◽  
Author(s):  
Robert P. Damadeo ◽  
Joseph M. Zawodny ◽  
Ellis E. Remsberg ◽  
Kaley A. Walker
Keyword(s):  
Stratospheric Ozone ◽  
Primary Source ◽  
Data Sets ◽  
Sampled Data ◽  
Uniform Sampling ◽  
Ozone Trends ◽  
Long Term Trends ◽  
Non Uniform Sampling ◽  
The Impact

Abstract. This paper applies a recently developed technique for deriving long-term trends in ozone from sparsely sampled data sets to multiple occultation instruments simultaneously without the need for homogenization. The technique can compensate for the non-uniform temporal, spatial, and diurnal sampling of the different instruments and can also be used to account for biases and drifts between instruments. These problems have been noted in recent international assessments as being a primary source of uncertainty that clouds the significance of derived trends. Results show potential recovery trends of ~ 2–3 %/decade in the upper stratosphere at mid-latitudes, which are similar to other studies, and also how sampling biases present in these data sets can create differences in derived "recovery" trends of up to ~ 1 %/decade if not properly accounted for. Limitations inherent to all techniques (e.g., relative instrument drifts) and their impacts (e.g., trend differences up to ~ 2 %/decade) are also described and a potential path forward towards resolution is presented.

scholarly journals Investigation of the impact of the project office on the socio-economic development of the municipality

2021 ◽  
Vol 12 (1) ◽  
pp. 157-172
Author(s):  
Alla Yu. Trusova ◽  
Vladimir I. Aksenov
Keyword(s):  
Economic Development ◽  
Development Strategy ◽  
Scientific Article ◽  
Management Tools ◽  
Project Approach ◽  
Regional Development Strategy ◽  
Socio Economic Development ◽  
Long Term Trends ◽  
The Impact

The complexity of the socio-economic situation at all levels requires a detailed study of the regional development strategy issues and monitoring the implementation of presidential and government decrees. Various approaches to management were considered, for example, the national projects development implementation issues. National projecting, as a new tool for implementing state concepts, is an effective management method. The set of the project office functions provides control over the implementation of national projects at the level of development of municipalities of the Russian Federation. Historically, the level of socio-economic development of the territory has been measured and is measured using the identification of long-term trends in the development of key socio-economic indicators. The article presents a methodology that allows you to evaluate the effectiveness of project management tools since based on the results of its assessment, you can make informed management decisions and judge the effectiveness of the work of local authorities. Therefore, the aim of the scientific article was to develop an effective methodology that allows us to evaluate the effectiveness of the project office functions implemented in the management of the socio-economic development of the municipality. As a result of the study, systemic relationships were revealed of the impact of the project office on the indicators of the socio-economic development of the municipality, which was presented in the work as an important aspect of the study, the significance of which is due to the priorities of sustainable, balanced, competitive, integrated development of the Russian regions. In connection with the socio-economic policy pursued by the state, which requires speedy acceleration of the socio-economic development of municipalities, the effectiveness of the result of the application of the project approach in the municipal authorities was studied in detail.

The Supreme Court as a Countermajoritarian Institution? The Impact of Public Opinion on Supreme Court Decisions

1993 ◽  
Vol 87 (1) ◽  
pp. 87-101 ◽  
Author(s):  
William Mishler ◽  
Reginald S. Sheehan
Keyword(s):  
Public Opinion ◽  
Supreme Court ◽  
Membership Change ◽  
Collective Decisions ◽  
The Supreme Court ◽  
Long Term Trends ◽  
Time Series Analyses ◽  
The Impact

Although normative questions about the role of the Supreme Court as a countermajoritarian institution have long excited controversy in democratic theory, empirical questions about how far the Court acts contrary to majoritarian opinion have received less attention. Time series analyses for the period 1956–89 indicate the existence of a reciprocal and positive relationship between long-term trends in aggregate public opinion and the Court's collective decisions. The Court's ideological composition changes in response to previous shifts in the partisan and ideological orientation of the president and Congress. The Court also responds to public opinion at the margins even in the absence of membership change. Since 1981, the relationship has vanished or turned negative in direction. The Court's ideological balance has been upset by an unbroken string of conservative-to-moderate appointments, thereby undermining the dynamics that promote judicial responsiveness and raising questions about the majoritarianism of the contemporary and future Court.

scholarly journals Spatial patterns of linear and nonparametric long-term trends in Baltic sea-level variability

2012 ◽  
Vol 19 (1) ◽  
pp. 95-111 ◽  
Author(s):  
R. V. Donner ◽  
R. Ehrcke ◽  
S. M. Barbosa ◽  
J. Wagner ◽  
J. F. Donges ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Spatial Patterns ◽  
Tide Gauge ◽  
Sufficient Information ◽  
Sea Level Variability ◽  
Advantages And Disadvantages ◽  
Long Term Trends ◽  
The Impact

Abstract. The study of long-term trends in tide gauge data is important for understanding the present and future risk of changes in sea-level variability for coastal zones, particularly with respect to the ongoing debate on climate change impacts. Traditionally, most corresponding analyses have exclusively focused on trends in mean sea-level. However, such studies are not able to provide sufficient information about changes in the full probability distribution (especially in the more extreme quantiles). As an alternative, in this paper we apply quantile regression (QR) for studying changes in arbitrary quantiles of sea-level variability. For this purpose, we chose two different QR approaches and discuss the advantages and disadvantages of different settings. In particular, traditional linear QR poses very restrictive assumptions that are often not met in reality. For monthly data from 47 tide gauges from along the Baltic Sea coast, the spatial patterns of quantile trends obtained in linear and nonparametric (spline-based) frameworks display marked differences, which need to be understood in order to fully assess the impact of future changes in sea-level variability on coastal areas. In general, QR demonstrates that the general variability of Baltic sea-level has increased over the last decades. Linear quantile trends estimated for sliding windows in time reveal a wide-spread acceleration of trends in the median, but only localised changes in the rates of changes in the lower and upper quantiles.

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