The effects of salinity, turbidity and flow on fish biomass estimated acoustically in two tidal rivers

2014 ◽  
Vol 65 (3) ◽  
pp. 267 ◽  
Author(s):  
V. F. Matveev ◽  
A. D. L. Steven
Keyword(s):  
Large Scale ◽  
River System ◽  
Fish Abundance ◽  
Practical Significance ◽  
Small Scale ◽  
Fish Biomass ◽  
Strongly Correlated ◽  
Commercial Catch ◽  
Four Seasons ◽  
Annual Means

Establishing drivers of fish abundance in estuaries is an important task of both theoretical and practical significance. Commercial catch data help explain large-scale variation in fish productivity; however, there is insufficient understanding of small-scale changes. We analysed correlations between acoustically estimated fish biomass (FB) and environmental variables, which included indices of primary productivity and physio-chemistry in a coastal river system during four seasons. Spatial series of FB were obtained for the Logan River (main estuary) and the Albert River (tributary) located in South East Queensland, Australia. Most of the year, FB was significantly higher in the Albert River. Annual means for discharge, salinity and pH were significantly lower, whereas phosphorus concentrations were higher in the Albert River. Out of 15 hydrological variables tested, FB was strongly correlated only with salinity, conductivity and turbidity. In the Albert River, where fish were larger, as indicated by greater target strengths, FB was positively correlated with river discharge. Our results suggest that salinity and turbidity can be important seasonal drivers of fish abundance in communities dominated by Mugil spp. and Nematalosa erebi and that the flow-biomass relationship may appear independent of the effects of primary production.

Empirical Studies on Demand Pull in Photovoltaic Sector of Twenty Countries

2013 ◽  
Vol 827 ◽  
pp. 451-456
Author(s):  
Mo Lin Huo ◽  
Bao Guo Shan
Keyword(s):  
Large Scale ◽  
Empirical Studies ◽  
Technical Innovation ◽  
Practical Significance ◽  
Small Scale ◽  
Market Growth ◽  
Demand Pull ◽  
Initial Stage ◽  
Acceleration Period ◽  
Diffusion Rates

High cost impedes large-scale deployment of photovoltaics (PV), and the technical innovation is one of most important factors of cost reduction, so how to accelerate the market pull for innovation has practical significance and theoretical value. This paper aims to analyze PV demand pull mechanism based on empirical evidence. According to the features of PV industry and technical innovation theories, make hypotheses of PV market pull and the relationship between diffusion rates and the market pull. Then propose testing method of the market pull and the coefficients assessing diffusion rates, and use historical data of twenty countries to conduct empirical studies. The testing results show that 70% of PV market in the twenty countries pulled technical innovation; at the initial stage of PV diffusion, the market pull was insignificant when the market kept at small scale and the diffusion rate can be indicated by the innovation coefficient; in the acceleration period, the market pull was insignificant when the market grew steeply and the rate can be indicated by the imitating coefficient. So in order to encourage demand pull, policy making is suggested to lead the market growth stable and sustained.

The large-scale Control of the Cotton Jassid in the Gezira and White Nile Areas of the Sudan

1952 ◽  
Vol 43 (3) ◽  
pp. 479-502 ◽  
Author(s):  
O. W. Snow ◽  
J. Taylor
Keyword(s):  
Chemical Control ◽  
Large Scale ◽  
Small Scale ◽  
Crop Season ◽  
Four Seasons ◽  
White Nile ◽  
Scale Control

The damage caused by the Cotton Jassid to the Egyptian-type cottons in the Gezira and White Nile areas of the Sudan is very considerable. Realisation of this fact has been greatly aided by chemical control of the pest in small-scale experiments, followed by large-scale work with tractor-drawn sprayers and with helicopters fitted with spraying equipment. This paper deals primarily with examination of available records pertaining to the cotton crops in the four seasons from 1946/47 to 1949/50, preceded firstly by an introduction which emphasises the importance of yield records in the appraisal and interpretation of losses from pests, and secondly by an account of certain aspects of the pest in the Gezira Scheme.Large-scale spraying to control the pest started in the Gezira in the crop season 1945/46; yield increases from about 1,250 feddans (acres) sprayed with 0·1 per cent. DDT emulsion were very satisfactory. In succeeding seasons increasing areas were sprayed; in 1947/48 spraying was extended to the cotton farms along the White Nile between Khartoum and Kosti; in 1949/50 the total area sprayed in the Sudan was over 150,000 feddans. Material and also methods and dates of application varied considerably.

scholarly journals Large-scale spatial heterogeneity of macrozooplankton in Lake of Geneva

1999 ◽  
Vol 56 (8) ◽  
pp. 1437-1451 ◽  
Author(s):  
Bernadette Pinel-Alloul ◽  
Catherine Guay ◽  
Nadine Angeli ◽  
Pierre Legendre ◽  
Pierre Dutilleul ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Water Temperature ◽  
Chlorophyll A ◽  
Large Scale ◽  
Abiotic Factors ◽  
Distribution Patterns ◽  
Small Scale ◽  
Lake Basin ◽  
Fish Biomass ◽  
Trophic Groups

Spatial distribution of macrozooplankton was studied during spring in Lake of Geneva to evaluate the influence of abiotic (water temperature and stability, nutrients) and biotic (bacteria, chlorophyll a, fish biomass) factors on macrozooplankton distribution. Mapping and spatial analyses revealed that abiotic factors, as well as crustacean abundances, were structured along a gradient in the great lake basin. Chlorophyll a biomass, bacteria density, cyclopoid abundance, and fish biomass showed more patchy or inshore-offshore distribution patterns. Using canonical analyses, we determined the relative contribution of the spatial and environmental factors to the distribution of macrozooplankton species and of trophic groups based on herbivory and omnivory/carnivory. The distribution of macrozooplankton can be explained by small-scale variations and lake gradients in abiotic and biotic factors, with a dominant contribution of the abiotic factors. Water temperature and stability, as well as ammonium, are the main factors related to macrozooplankton distribution in Lake of Geneva during spring. Chlorophyll a biomass was also related to the distribution of cyclopoids. The canonical models explained 35-72% of the variance in the distribution of total crustaceans, species, and trophic groups. However, 28-65% of the macrozooplankton variance remained unexplained, which may be due to fine-scale variations in other environmental factors.

scholarly journals Strongly Correlated Electronic States in Aqueous Micellar Surfactant

2021 ◽  
Author(s):  
Yuri Mirgorod
Keyword(s):  
Large Scale ◽  
Electronic States ◽  
Micelle Formation ◽  
Thermal Fluctuations ◽  
Small Scale ◽  
Strongly Correlated ◽  
Micellar Solutions ◽  
X Ray ◽  
Cooperative Effects ◽  
White Spots

Abstract Strongly correlated electronic states (SCES), that determine the anomalies of physicochemical properties, are well-known for solid materials at low temperatures. According to the mechanism of manifestation their existence can be assumed in biological cells with white spots, which makes us look into this challenging problem in detail. The paper presents its solution through a study of simple models of micellar solutions of ionic surfactants. The process of micelle formation with accompanying liquid-liquid phase transition makes us pay attention to possible anomalies of properties. Therefore the SCES of water micellar solution has been tested by compenstion and cooperative effects; and by small-angle, wide-angle X-ray, dynamic and chiral scattering of electromagnetic radiation. The solution water is represented by ensembles of small nano systems. Therefore, thermal (cavities for micelles 2-6 nm) and quantum (0.2-0.3 nm) fluctuations of water appear in the zone of concentration of micelle formation. Their energy is approximately equal to the H-bond. Contraction (expansion) of water H-bonds network of due to quantum fluctuations on a small scale correlates with the expansion (contraction) of the in the cavities in the micelles H-bonds network due to thermal fluctuations on a large scale. This phenomenon is caused by SСES.

scholarly journals Drivers of the accuracy of developers’ early stage cost estimates in residential construction

2016 ◽  
Vol 21 (1) ◽  
pp. 4-20 ◽  
Author(s):  
Brendon Lim ◽  
Madhav P. Nepal ◽  
Martin Skitmore ◽  
Bo Xiong
Keyword(s):  
Construction Projects ◽  
Large Scale ◽  
Early Stage ◽  
Practical Significance ◽  
Small Scale ◽  
Residential Construction ◽  
Specific Information ◽  
Cost Estimates ◽  
Content Type ◽  
Cost Drivers

Purpose – Preliminary cost estimates for construction projects are often the basis of financial feasibility and budgeting decisions in the early stages of planning and for effective project control, monitoring and execution. The purpose of this paper is to identify and better understand the cost drivers and factors that contribute to the accuracy of estimates in residential construction projects from the developers’ perspective. Design/methodology/approach – The paper uses a literature review to determine the drivers that affect the accuracy of developers’ early stage cost estimates and the factors influencing the construction costs of residential construction projects. It used cost variance data and other supporting documentation collected from two case study projects in South East Queensland, Australia, along with semi-structured interviews conducted with the practitioners involved. Findings – It is found that many cost drivers or factors of cost uncertainty identified in the literature for large-scale projects are not as apparent and relevant for developers’ small-scale residential construction projects. Specifically, the certainty and completeness of project-specific information, suitability of historical cost data, contingency allowances, methods of estimating and the estimator’s level of experience significantly affect the accuracy of cost estimates. Developers of small-scale residential projects use pre-established and suitably priced bills of quantities as the prime estimating method, which is considered to be the most efficient and accurate method for standard house designs. However, this method needs to be backed with the expertise and experience of the estimator. Originality/value – There is a lack of research on the accuracy of developers’ early stage cost estimates and the relevance and applicability of cost drivers and factors in the residential construction projects. This research has practical significance for improving the accuracy of such preliminary cost estimates.

scholarly journals Significance of trends in gait dynamics

2019 ◽  
Author(s):  
Klaudia Kozlowska ◽  
Miroslaw Latka ◽  
Bruce J. West
Keyword(s):  
Large Scale ◽  
Stride Length ◽  
Human Gait ◽  
Small Scale ◽  
Strongly Correlated ◽  
Scaling Exponents ◽  
Treadmill Speed ◽  
Gait Parameters ◽  
Instantaneous Values ◽  
Spatio Temporal

AbstractTrends in time series generated by physiological control systems are ubiquitous. Determining whether trends arise from intrinsic system dynamics or originate outside of the system is a fundamental problem of fractal series analysis. In the latter case, it is necessary to filter out the trends before attempting to quantify correlations in the noise (residuals). For over two decades, detrended fluctuation analysis (DFA) has been used to calculate scaling exponents of stride time (ST), stride length (SL), and stride speed (SS) of human gait. Herein, rather than relying on the very specific form of detrending characteristic of DFA, we adopt Multivariate Adaptive Regression Splines (MARS) to explicitly determine trends in spatio-temporal gait parameters during treadmill walking. Then, we use the madogram estimator to calculate the scaling exponent of the corresponding MARS residuals. The durations of ST and SL trends are determined to be independent of treadmill speed and have distributions with exponential tails. At all speeds considered, the trends of ST and SL are strongly correlated and are statistically independent of their corresponding residuals. The group-averaged values of scaling exponents of ST and ST MARS residuals are slightly smaller than 0.5, indicating weak anti-persistence. Thus, contrary to the interpretation prevalent in the literature, the statistical properties of ST and SL time series originate from the superposition of large scale trends and small scale fluctuations. We show that trends serve as the control manifolds about which ST and SL fluctuate. Moreover, the trend speed, defined as the ratio of instantaneous values of SL and ST trends, is tightly controlled about the treadmill speed. The strong coupling between the ST and SL trends ensures that the concomitant changes of their values correspond to movement along the constant speed goal equivalent manifold as postulated by Dingwell et al. doi:10.1371/journal.pcbi.1000856.Author summaryDuring treadmill walking, the subject’s stride time (ST) and stride length (SL) must yield a stride speed which can fluctuate over a narrow range centered on the treadmill belt’s speed. The fact that both ST and SL are persistent is an intriguing property of human gait. For persistent fluctuations any deviation from the mean value is likely to be followed by a deviation in the same direction. To trace the origin of such persistence, we used a novel approach to determine trends in spatio-temporal gait parameters. We find that the trends of ST and SL of a subject are strongly correlated and are statistically independent of their corresponding residuals. Moreover, the trend speed, defined as the ratio of instantaneous values of SL and ST trends, is tightly controlled about the treadmill speed. The persistence of gait parameters stems from superposition of large scale trends and small scale fluctuations.

scholarly journals A Fast Multiscale Clustering Approach Based on DBSCAN

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Runzi Chen ◽  
Shuliang Zhao ◽  
Meishe Liang
Keyword(s):  
Large Scale ◽  
Computational Cost ◽  
Scaling Up ◽  
Practical Significance ◽  
Small Scale ◽  
Large Scale Data ◽  
Traditional Algorithm ◽  
Multiscale Clustering ◽  
Clustering Approach ◽  
Scale Data

Multiscale brings great benefits for people to observe objects or problems from different perspectives. It has practical significance for clustering on multiscale data. At present, there is a lack of research on the clustering of large-scale data under the premise that clustering results of small-scale datasets have been obtained. If one does cluster on large-scale datasets by using traditional methods, two disadvantages are as follows: (1) Clustering results of small-scale datasets are not utilized. (2) Traditional method will cause more running overhead. Aims at these shortcomings, this paper proposes a multiscale clustering framework based on DBSCAN. This framework uses DBSCAN for clustering small-scale datasets, then introduces algorithm Scaling-Up Cluster Centers (SUCC) generating cluster centers of large-scale datasets by merging clustering results of small-scale datasets, not mining raw large-scale datasets. We show experimentally that, compared to traditional algorithm DBACAN and leading algorithms DBSCAN++ and HDBSCAN, SUCC can provide not only competitive performance but reduce computational cost. In addition, under the guidance of experts, the performance of SUCC is more competitive in accuracy.

Small-Scale Science to Large-Scale Profession

2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  
Large Scale ◽  
Small Scale

Development of Physics Learning Module Based on Guided Inquiry with Light Wave Material in Class XI of Senior High School

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati
Keyword(s):  
Large Scale ◽  
Learning Strategy ◽  
Student Response ◽  
Average Score ◽  
Small Scale ◽  
Design Development ◽  
Teacher Response ◽  
Student Responses ◽  
Analysis Design ◽  
Scientific Skills

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.

Intelligent Lighting Control System in Large-Scale Sports Competition Venues

2018 ◽  
pp. 172-182 ◽  
Author(s):  
Shengmin CAO
Keyword(s):  
Control System ◽  
Large Scale ◽  
Comprehensive Evaluation ◽  
Evaluation Model ◽  
Fuzzy Comprehensive Evaluation ◽  
Practical Significance ◽  
Lighting Control ◽  
Sports Events ◽  
Planning And Design ◽  
Comprehensive Evaluation Model

This paper mainly studies the application of intelligent lighting control system in different sports events in large sports competition venues. We take the Xiantao Stadium, a large­scale sports competition venue in Zaozhuang City, Shandong Province as an example, to study its intelligent lighting control system. In this paper, the PID (proportion – integral – derivative) incremental control model and the Karatsuba multiplication model are used, and the intelligent lighting control system is designed and implemented by multi­level fuzzy comprehensive evaluation model. Finally, the paper evaluates the actual effect of the intelligent lighting control system. The research shows that the intelligent lighting control system designed in this paper can accurately control the lighting of different sports in large stadiums. The research in this paper has important practical significance for the planning and design of large­scale sports competition venues.

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