Effect of Organic Color and Turbidity of Secchi Disk Transparency

1978 ◽  
Vol 35 (11) ◽  
pp. 1410-1416 ◽  
Author(s):  
Patrick L. Brezonik
Keyword(s):  
Regression Analysis ◽  
Linear Relationship ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Chlorophyll A ◽  
Light Attenuation ◽  
Secchi Disk ◽  
Concentrated Solutions ◽  
Secchi Disk Transparency ◽  
Statistical Relationships

Secchi disk transparency in lakes is a function not only of the turbidity caused primarily by plankton, but also of the organic color level in the water. Multiple regression analysis of data from 55 Florida lakes yielded a close-fitting equation of the type (SD)−1 = a(Color) + b(Turbidity) + c. The statistical relationships between inverse transparency and chlorophyll a and between log transparency and log chlorophyll a exhibited greater scatter. Experiments in which concentrated solutions of humic substances were added to a large plastic "limno-bag" verified the linear relationship between (SD)−1 and color content but yielded a different slope than that obtained by regression analysis. The maximum possible transparency (assuming zero turbidity) was similar for both the experimental and regression relationships at color levels above 50 platinum (Pt) units, but increasingly divergent results were predicted by the two approaches at lower color levels. At a color of 100 Pt units, the maximum Secchi disk transparency is about 2.4–2.8 m. Because of the crudeness of transparency measurements, use of the above regression equation to compute transparencies from measured turbidities appears to be more reliable than use of the experimentally derived equation. Key words: Secchi disk, transparency, color, turbidity, trophic indicator, chlorophyll a, light attenuation

Cladoceran body length and Secchi disk transparency in northeastern U.S. lakes

2003 ◽  
Vol 60 (12) ◽  
pp. 1477-1486 ◽  
Author(s):  
Richard S Stemberger ◽  
Eric K Miller
Keyword(s):  
Chlorophyll A ◽  
Body Length ◽  
Nutrient Loading ◽  
Size Structure ◽  
Light Attenuation ◽  
Water Clarity ◽  
Secchi Disk ◽  
Particulate Carbon ◽  
Secchi Disk Transparency ◽  
Organic Particles

Mean cladoceran body length of 59 northeastern U.S. lakes was estimated from functional groups that broadly define taxonomic, body size, and grazing potential. Multiple regression of body length, color, and chlorophyll a or total phosphorus against Secchi disk transparency explained 72% and 83% of the variation across lakes, respectively. Analysis that included body length, color, and particulate carbon, a proxy for light backscattering and absorption by suspended organic particles, explained 85% of the variance in transparency. Body length was as important a predictor of water clarity as chemical factors. Furthermore, body length was significantly correlated to temporal variation in transparency within lakes. Because cladocerans primarily filter organic particles in size ranges having high light attenuation efficiencies, body length was consistently more strongly correlated to transparency than to chlorophyll a. Monitoring cladoceran body length should help to distinguish changes in lake transparency due to nutrient loading from changes that reflect fish population size structure and predation intensity on zooplankton. This simple size index can greatly increase the interpretative value of Secchi transparency observations to lake managers.

scholarly journals Mencari Variabel-variabel Yang Mempengaruhi Sikap Mental Entrepreneural (Wirausaha)Pada Pemerintah Kabupaten Serdang Bedagai

2006 ◽  
Vol 6 (2) ◽  
pp. 155
Author(s):  
Arfan Ikhsan
Keyword(s):  
Regression Analysis ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Mental Attitude ◽  
Independent Variables ◽  
Independent Variable

<p class="Style1">This research try to find some variables that influence entrepreneurial mental attitude at government of Serdang Bedagai Regency. independent variable which considered in this research is hierarchy, formalizes, trust, mission, ethics and regulation barriers level. Those independent variables will be able to improve society satisfaction, reduc­tion of level of bureaucracy and improvement of risking tendency. The data of this research collected from organization chart of Serdang Bedagai Regency. Amount of 68 responders participated in this research. Hereinafter this data processed by using multiple regression analysis. The result shows that formalizes, trust, mission, ethics and regulation barriers level have an effect significantly toward society satisfaction and also bureaucracy. Meanwhile risking tendency is significantly influenced by hierarchy, formalizes, mission and ethics.</p><p class="Style1" align="center">Key Words: hierarchy, formalizes, trust, mission, ethics and regulation barriers level</p>

scholarly journals Pola Asuh Demokratis, Kepercayaan Diri dan Kemandirian Mahasiswa Baru

2013 ◽  
Vol 2 (2) ◽  
Author(s):  
Nur Asiyah
Keyword(s):  
Regression Analysis ◽  
Data Analysis ◽  
College Student ◽  
Correlation Analysis ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Significant Relation ◽  
Self Confidence ◽  
The Subject

Abstract. The purpose of this research was to examine the relation between democratic-parenting and self confidence with independent new college student. The subject of the study were 131 new  college student of faculty preaching the state islamic institute sunan ampel surabaya. Data were collected by scale of democratic-parenting, self confidence and independent scale. The data analysis used multiple regression analysis showed that the democratic-parenting anda self confidence have a significant relation with independent new  college student. The result of correlation analysis between either democratic-parenting or self confidence with independent showed a positive correlation signifycantly. Variables of democratic parenting and self confidence give effecttive contribution toward independent new college student about 51,3%.Key words : Democratic-Parenting, Self Confidence, Independent New College Student.

SEASONAL VARIATION IN CAMBIAL ELECTRICAL RESISTANCE AND ITS RELATION TO GROWTH IN TWO CULTIVARS OF PEACH

1985 ◽  
Vol 65 (2) ◽  
pp. 345-349 ◽  
Author(s):  
M. WISNIEWSKI ◽  
A. LINN BOGLE ◽  
C. L. WILSON
Keyword(s):  
Regression Analysis ◽  
Seasonal Variation ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Electrical Resistance ◽  
Prunus Persica ◽  
Main Trunk ◽  
Increment Core ◽  
Peach Trees

Seasonal trends in cambial electrical resistance (CER) of Loring and Redhaven peach trees (Prunus persica (L.) Batsch) were monitored with the use of a Shigometer. Three readings were taken on the main trunk of each tree periodically from early June 1981 through early December 1982. Individual records were maintained for each tree. One increment core was also taken from the trunk of each tree in late November 1982. The data suggested a relationship between CER and the onset of dormancy and a multiple regression analysis demonstrated a significant correlation between CER and growth, cultivar, and a growth-cultivar interaction (R2 = 0.61).Key words: Prunus persica, dormancy, growth, electrical resistance, peach

scholarly journals A method for geospatial modeling and mapping of climatic characteristics from meteostation observation data

2011 ◽  
pp. 245-253
Author(s):  
A. Mkrtchian ◽  
P. Shuber
Keyword(s):  
Regression Analysis ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Land Surface ◽  
Observation Data ◽  
Geospatial Modeling ◽  
Geostatistical Interpolation ◽  
Mapping Techniques ◽  
Land Surface Parameters ◽  
Climatic Characteristics

In the paper the fundamentals of the method of geospatial modeling of climatic fields based on multiple regression analysis and geostatistics are given. This method is promising as a tool for the optimization and formalization of the climatic mapping techniques and the improvement of the precision and reliability of climatic maps. Key words: geospatial modeling, climatic characteristics, land-surface parameters, geostatistical interpolation.

scholarly journals Crustacean zooplankton species richness in Chilean lakes and ponds (23º-51ºS)

2017 ◽  
Vol 41 (3) ◽  
pp. 600-605
Author(s):  
Patricio De los Ríos-Escalante
Keyword(s):  
Regression Analysis ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Chlorophyll A ◽  
Crustacean Zooplankton ◽  
Species Number ◽  
Factors Affecting ◽  
Chlorophyll A Concentration ◽  
Potential Factors ◽  
Water Ecosystems

Chilean inland-water ecosystems are characterized by their low species-level biodiversity. This study analyses available data on surface area, maximum depth, conductivity, chlorophyll-a concentration, and zooplankton crustacean species number in lakes and ponds between 23º and 51ºS. The study uses multiple regression analysis to identify the potential factors affecting the species number. The partial correlation analysis indicated a direct significant correlation between chlorophyll-a concentration and species number, whereas the multiple regression analysis indicated a direct significant response of species number to latitude and chlorophyll-a concentration. These results agree with findings from comparable ecosystems in Argentina and New Zealand.

scholarly journals Pengaruh Persepsi Konsumen Terhadap Atribut Produk pada Sikap Terhadap Produk dan Niat Pembelian Ulang : Studi Empirik Pengambilan Keputusan pada Kategori Produk Daging Olahan Beku (The Effect of Consumer Perception on Product Attributes to Attitude Towar

2012 ◽  
Vol 34 (2) ◽  
pp. 131
Author(s):  
Antofany Yusticia Ahmadi ◽  
Suci Paramitasari Syahlani ◽  
F. Trisakti Haryadi
Keyword(s):  
Regression Analysis ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Purchase Intention ◽  
Sampling Method ◽  
Consumer Perception ◽  
Product Attribute ◽  
Repeat Purchase ◽  
Relationship Of ◽  
Product Study

<p>The objectives of the study were to measure the influence of product attribute perception to attitude toward product, the effect of attitude toward product to repeat purchase intention and to confirm that attitude toward product is<br />a mediating variable between effect in relationship of product attribute perception to repeat purchase intention. One hundred (100) housewives determined by judgmental sampling method were used in the study. The criterion of<br />respondent selected was that he/she has a role as food buying decision maker. Data were analyzed by simple and multiple regression analysis. The results indicated that perception on product attribute had significant effect on<br />attitudes toward product and attitude toward product influenced repeat purchase intention. The study showed that 36.5% attitude toward product can be explained by consumer product attribute perception, while 61.6% repeat purchase intention can be explained by attitude toward product. Study also confirmed that attitude toward product attribute was a fully mediating variable relationship of attitude and purchase intention.</p><p>(Key words: Perception, Attitude, Repeat purchase intention)<br /><br /></p>

scholarly journals Association between peripheral lymphocyte count and the mortality risk of COVID-19 inpatients

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Saibin Wang ◽  
Yijun Sheng ◽  
Junwei Tu ◽  
Lanlan Zhang
Keyword(s):  
Regression Analysis ◽  
Linear Relationship ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Mortality Risk ◽  
Area Under The Curve ◽  
Peripheral Lymphocyte ◽  
Hospitalized Patients ◽  
Non Linear ◽  
The Relationship

Abstract Background To explore the relationship between peripheral lymphocyte counts (PLCs) and the mortality risk of coronavirus disease 2019 (COVID-19), as well as the potential of PLC for predicting COVID-19 hospitalized patients death. Methods Baseline characteristics, laboratory tests, imaging examinations, and outcomes of 134 consecutive COVID-19 hospitalized patients were collected from a tertiary hospital in Wuhan city from January 25 to February 24, 2020. Multiple regression analysis was used to analyze the relationship between the PLC at admission and mortality risk in COVID-19 patients and to establish a model for predicting death in COVID-19 hospitalized patients based on PLC. Results After adjusting for potential confounding factors, we found a non-linear relationship and threshold saturation effect between PLC and mortality risk in COVID-19 patients (infection point of PLC: 0.95 × 109/L). Multiple regression analysis showed that when PLCs of COVID-19 patients were lower than 0.95 × 109/L, the patients had a significantly higher mortality risk as compared to COVID-19 patient with PLCs > 0.95 × 109/L (OR 7.27; 95% CI 1.10–48.25). The predictive power of PLC for death in COVID-19 patients (presented as area under the curve) was 0.78. The decision curve analysis showed that PLC had clinical utility for the prediction of death in COVID-19 inpatients. Conclusions PLC had a non-linear relationship with mortality risk in COVID-19 inpatients. Reduced PLCs (< 0.95 × 109/L) were associated with an increased mortality risk in COVID-19 inpatients. PLCs also had a potential predictive value for the death of COVID-19 inpatients.

scholarly journals Kecerderdasan Emosi, Kecerdasan Spiritual dan Perilaku Prososial Santri Pondok Pesantren Nasyrul Ulum Pamekasan

2012 ◽  
Vol 1 (2) ◽  
Author(s):  
Zamzami Sabiq
Keyword(s):  
Emotional Intelligence ◽  
Regression Analysis ◽  
Data Analysis ◽  
Social Behavior ◽  
Prosocial Behavior ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Significant Relation ◽  
Pro Social Behavior

Abstract. The purpose of this research was to examine the relations between emotional intelligent and spiritual intelligent with pro-social behavior. The subjects of the study were 175 students of Pondok Pesantren Nasyrul Ulum Pamekasan, consist of 96 boys and 79 girls. Data were collected by scales of emotional intelligent, spiritual intelligent, and pro-social behavior. The data analysis used  multiple regression analysis and then correlations. Results of multiple regression analysis showed that the emotional intelligent and spiri-tual intelligent have a significant relation with prosocial behavior. The result of correlation analyses between either emotional intelligence or spiri-tual intelligence with prosocial behavior showed a positive correlation signify-cantly. Variables of emotional intelligent and spiritual intelligent give effect-tive contribution toward prosocial behavior about 55,1%. Key words: pro-social behavior, emotional intelligent, spiritual intelligent

scholarly journals Pengaruh Motivasi Kerja, Kepemimpinan dan Budaya Organisasi Terhadap Kepuasan Kerja (Studi Pada Djari-Djari Art of Refelexologi Banjarmasin)

2017 ◽  
Vol 1 (2) ◽  
Author(s):  
Muhammad Rudiansyah
Keyword(s):  
Job Satisfaction ◽  
Organizational Culture ◽  
Regression Analysis ◽  
Key Words ◽  
Multiple Regression Analysis ◽  
Empirical Evidence ◽  
Work Motivation ◽  
Testing Hypothesis ◽  
Dominant Effect ◽  
Employee Job Satisfaction

This study aims to obtain an empirical evidence about the effect of work motivation, leadership and organizational culture on job satisfaction and also to identity which variable has a dominant effect on employee job satisfaction at Djari-djari Art Of Refelexologi Banjarmasin. Population of this study were 36 people who were all employees. This study used a quantitative exploratory descriptive design . Analyzing data used the multiple regression Analysis. In testing hypothesis simultaneonsly, F test was used and T test was used in testing hypothesis patially. The result of this study showed that work motivation, leadership, and organizational culture simultaneonsly have an effect on employee job satisfaction . Whilepartially. Leadership has a dominant effect on employee job satispaction at Djari-djari Art Of Refeloxologi Banjarmasin. Key words : Work Motivation, Leadership, Organizational Culture. Job satisfaction.

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