The Harvesting Effect on a Fish Population

2016 ◽  
Vol 11 (2) ◽  
pp. 191-204 ◽  
Author(s):  
А.И. Абакумов ◽  
A.I. Abakumov
Keyword(s):  
Fish Population ◽  
Dimensional Structure ◽  
Population Stability ◽  
Criterion Function ◽  
Factors Affecting ◽  
Time Period ◽  
Fishery Impact ◽  
Dimensional Distribution ◽  
Environmental Variations ◽  
The Impact

Fishery is one of the main environmental factors affecting fish population. In this paper we study the dynamics of population’s dimensional distribution under the influence of environmental variations with and without a fishery impact. The characteristics of population under consideration correspond to pelagic or semi-pelagic population, such as the populations of pollack (Theragra chalcogramma) inhabiting the northern seas of Pacific Ocean. To study the effect of fishery upon a population the problem of harvesting optimization with the amount of profit for a given time period as a criterion function is solved. The impact of population replenishment on the population and catch dynamics was studied and the smoothing influence of dimensional structure on the changes of environment and fishery was revealed. The seasonal changes of environment only increase the population stability.

scholarly journals Key factors affecting people’s unwillingness to be confined during the COVID-19 pandemic in Spain: a large-scale population study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marina Martinez-Garcia ◽  
Alejandro Rabasa ◽  
Xavier Barber ◽  
Kristina Polotskaya ◽  
Kristof Roomp ◽  
...  
Keyword(s):  
Large Scale ◽  
Psychological Impact ◽  
Important Variable ◽  
Policy Makers ◽  
Factors Affecting ◽  
Time Period ◽  
Economic Support ◽  
Gender And Age ◽  
Scale Population ◽  
The Impact

AbstractPopulation confinements have been one of the most widely adopted non-pharmaceutical interventions (NPIs) implemented by governments across the globe to help contain the spread of the SARS-CoV-2 virus. While confinement measures have been proven to be effective to reduce the number of infections, they entail significant economic and social costs. Thus, different policy makers and social groups have exhibited varying levels of acceptance of this type of measures. In this context, understanding the factors that determine the willingness of individuals to be confined during a pandemic is of paramount importance, particularly, to policy and decision-makers. In this paper, we study the factors that influence the unwillingness to be confined during the COVID-19 pandemic by the means of a large-scale, online population survey deployed in Spain. We perform two types of analyses (logistic regression and automatic pattern discovery) and consider socio-demographic, economic and psychological factors, together with the 14-day cumulative incidence per 100,000 inhabitants. Our analysis of 109,515 answers to the survey covers data spanning over a 5-month time period to shed light on the impact of the passage of time. We find evidence of pandemic fatigue as the percentage of those who report an unwillingness to be in confinement increases over time; we identify significant gender differences, with women being generally less likely than men to be able to sustain long-term confinement of at least 6 months; we uncover that the psychological impact was the most important factor to determine the willingness to be in confinement at the beginning of the pandemic, to be replaced by the economic impact as the most important variable towards the end of our period of study. Our results highlight the need to design gender and age specific public policies, to implement psychological and economic support programs and to address the evident pandemic fatigue as the success of potential future confinements will depend on the population’s willingness to comply with them.

Impact of Saudi's Membership in Global and Arab Economic Blocs on its Agricultural Foreign Trade

2021 ◽  
Vol 9 (4) ◽  
pp. 230-245
Author(s):  
Rehab Said Ibrahem ◽  
Eman Aish Al brahim
Keyword(s):  
Foreign Trade ◽  
Secondary Data ◽  
Economic Stability ◽  
Kingdom Of Saudi Arabia ◽  
Factors Affecting ◽  
Economic Relations ◽  
Agricultural Exports ◽  
Time Period ◽  
International Economic Relations ◽  
The Impact

In recent years, the world has witnessed many changes in international economic relations, and the global system has crystallized into major economic blocs aimed at strengthening the position of these blocs in the framework of global international trade and economic stability. Accordingly, the research aims to study the impact of the accession of the Kingdom of Saudi Arabia to the membership of some economic blocs on Saudi agricultural foreign trade during the time period (1995-2019). By depend on both descriptive and quantitative statistical analysis. To study the evolution of the value of agricultural exports and imports and the most important factors affecting each of them, used of some indicators of export competitiveness such as a measure of geographical and commodity concentration. Also used the simultaneous equations method to build an econometric model to analyze the structure of agricultural foreign trade and its estimation by Two-Stage least squares (2SLS) method, the paper predicts the future of Saudi agricultural foreign trade. The research relied on secondary data. The results of the study expect that the average per capita share of agricultural exports, imports and agricultural Balance Deficit will reach about 600, 3.600 and 2.900 thousand riyals, respectively, during the year 2026.

Liquidity creation or de‐creation: evidence from US property and liability insurance industry

2013 ◽  
Vol 39 (10) ◽  
pp. 938-962 ◽  
Author(s):  
Byeongyong Paul Choi ◽  
Jin Park ◽  
Chia‐Ling Ho
Keyword(s):  
Insurance Industry ◽  
Content Type ◽  
Factors Affecting ◽  
Depository Institutions ◽  
Time Period ◽  
The Us ◽  
Financial Characteristics ◽  
Property And Liability Insurance ◽  
The Impact ◽  
The Relationship

PurposeThe purpose of this study is two‐fold. The first purpose is to properly measure the level of US property and liability (P/L) insurers liquidity creation, applying the liquidity creation measure developed by Berger and Bouwman. The second purpose is to identify factors affecting P/L insurers' liquidity creation using a regression. Particularly, this paper tests two competing hypotheses regarding the relationship between the level of capital and liquidity creation.Design/methodology/approachThe paper calculates liquidity creation for the US P/L insurers. First, the paper categorizes all items in assets, liabilities and surplus into liquid, semi‐liquid, or illiquid. This process is based on the ease, cost, and time for insurers to meet their contractual obligation to obtain liquid funds or to pay off their liability. The paper also constructs the regression model to test the impact of insurers' surplus level on liquidity creation while controlling for the firm‐specific variables. The paper examines this relationship for the time period between 1998 and 2007.FindingsContrary to the study of depository institutions, the paper reports that P/L insurers are liquidity destroyers than liquidity creators. This paper also provides that liquidity destruction varies over time and differs among insurers in different size. The total amount of liquidity destruction ranges from 47 to 58 percent of insurer total asset. In addition, the results of a regression show that insurer capital is negatively related to the level of liquidity creation. This provides implications that insurers with lower level of capital face more regulatory requirements and are forced to meet liquidity demand more.Practical implicationsThe level of liquidity creation and the trend of liquidity creation of P/L insurers are of particular interest to regulators and consumers because the level of liquidity creation as shown during the financial crisis has a significant adverse impact on the financial intermediaries.Originality/valueThe paper do not aware of any study that attempts to measure liquidity creation by insurers and its relationship with both organizational and financial characteristics. The paper reports that P/L insurers are, unlike depository institutions, liquidity destroyers. Whether or not P/L insurers create/destroy liquidity is an interesting economic question to shed light on the roles of P/L insurers as a financial intermediary.

Factors Affecting School Quality In Florida

2014 ◽  
Vol 7 (2) ◽  
pp. 69
Author(s):  
Barry Thornton ◽  
Gordon Arbogast
Keyword(s):  
No Child Left Behind ◽  
School Quality ◽  
High School Graduates ◽  
State University ◽  
Social Variables ◽  
State University System ◽  
Factors Affecting ◽  
Left Behind ◽  
Time Period ◽  
The Impact

This paper examines the factors that are theorized to be determinants of school quality in the 67 counties of Florida from 2000 to 2011. The model constructed for this purpose is comprised of a mix of independent variables that include county educational attainment (number of high school graduates and State University System enrollees) and economic factors (median household income, unemployment rate, number of housing starts, and property tax revenue per student). Furthermore, the model also considers 4 demographic/social variables (percent of population from 5 to 17 years old, percent white, percent female, and crime rate), as well as a variable for trend. The trend variable allows inferences to be made about the impact of the No Child Left Behind Act of 2001. It is hypothesized that these 11 variables will explain the variation in school quality by county over the observed time period.

scholarly journals Impact of Sustainable Development and Environmental Protection on the Volume of Domestic Hard Coal Sales in Poland

Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 443
Author(s):  
Aurelia Rybak ◽  
Ewelina Włodarczyk
Keyword(s):  
Arima Model ◽  
Hard Coal ◽  
Upward Trend ◽  
Factors Affecting ◽  
Explanatory Variables ◽  
Time Period ◽  
World Markets ◽  
Armax Model ◽  
The Impact ◽  
Significant Factors

The paper presents the results of an analysis of the impact of activities related to the implementation of Poland’s climate policy on the level of demand for hard coal. The authors used sets of indicators built by Eurostat during the analysis. The analysis was based on a set of indicators that had not previously been used for this purpose. The applied ARAMAX model made it possible to study the impact of the presented indicators on the volume of demand for hard coal in Poland. They were introduced to the ARMAX model as explanatory variables. The demand for hard coal in Poland was the dependent variable. The set of indicators was verified, and finally only statistically significant factors were used to build the model. The forecast of the demand for hard coal was made until 2022. It showed that the volume of coal sales would systematically fall as long as factors affecting demand remain constant. However, an additional factor was taken into account in the analysis, namely the increase in demand and prices for hard coal on world markets. The ARIMA model was used to forecast price levels for the next 12 months. The forecast indicates that the time series of prices should maintain an upward trend within the examined time period. Building an accurate and reliable forecast is the basis for effective planning of coal production and is adjusted to the demand for this fuel.

DAMPAK KEBIJAKAN FISKAL TERHADAP KINERJA SEKTOR PERTANIAN DI SULAWESI TENGGARA

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
La Ode Jabuddin ◽  
Ayub M Padangaran ◽  
Azhar Bafadal Bafadal
Keyword(s):  
Fiscal Policy ◽  
Interest Rates ◽  
Agricultural Sector ◽  
Simultaneous Equations ◽  
Poor People ◽  
Land Area ◽  
Factors Affecting ◽  
Historical Simulation ◽  
The Impact ◽  
Direct Expenditure

This study aims to: (1) Knowing the dynamics of fiscal policy and the performance of the agricultural sector, (2) Analyze the factors that influence fiscal policy and the performance                   of the agricultural sector, and (3) Analyzing the impact of fiscal policy on the performance of the agricultural sector. The data used in this study were pooled 2005-2013 data in the aggregate. Econometric model the impact of fiscal policy on the performance of the agricultural sector is built in the form of simultaneous equations, consisting of 7 equations with 25 total variables in the model, 7 endogenous variables, 12 exogenous variables, and 6 variables lag. The model is estimated by 2SLS method SYSLIN procedures and historical simulation with SIMNLIN procedure.The results showed that: (1) The development of fiscal policy in Southeast Sulawesi from year to year tends to increase, (2) The performance of the agricultural sector from the aspect of GDP has decreased, from the aspect of labor is still consistent, in terms of investment to grow positively, and assign roles which means to decrease the number of poor people, (3) factors affecting fiscal policy is local revenues, equalization funds, other revenues, as well as the lag fiscal policy, (4) the factors that affect the performance of the agricultural sector from the aspect GDP is labor, direct expenditure and GDP lag; from the aspect of labor is the total labor force, investment, land area, direct expenditure, as well as the lag of labor; from the aspect of investment is influenced by GDP per capita, land area, interest rates and investment lag; as well as from the aspect of poor people, are affected by population, investments, direct expenditure and poverty lag, (5). Fiscal policy impact on the agricultural sector GDP increase, a decrease in the number of poor, declining agricultural laborers, and a decrease in the amount of investment in the agricultural sector.Keywords: Fiscal policy, the performance of the agricultural sector, the simultaneous equations

Structural Model of Service Quality Factors Affecting Loyalty Sustainability

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Eman Al-erqi ◽  
◽  
Mohd Lizam Mohd Diah ◽  
Najmaddin Abo Mosali ◽  
◽  
...  
Keyword(s):  
International Students ◽  
Service Quality ◽  
Goodness Of Fit ◽  
Structural Model ◽  
Quality Factors ◽  
Factors Affecting ◽  
Measurement Models ◽  
Confirmatory Factor ◽  
The University ◽  
The Impact

This study seeks to address the impact of service quality affecting international student's satisfaction towards loyalty tothe Universiti Tun Hussein Onn Malaysia(UTHM). The aim of thestudy is to develop relationship between service quality factor and loyalty to the university from the international students’ perspectives. The study adopted quantitative approach where data was collected through questionnaire survey and analysed statistically. A total of 246 responses were received and found to be valid. The model was developed and analysed using AMOS-SEM software. Confirmatory factor analysis (CFA) function of the software was to assessed the measurement models and found that all the models achieved goodness of fit. Then path analysis function was used to assessed structural model and found that service qualityfactors have a significant effect on the students’ satisfaction and thus affecting the loyaltyto the university. Hopefully the outcome form this study will benefit the university in providing services especially to the international students.

Epigenetic Studies in Psychotherapy: A Systematic Review

2020 ◽  
Vol 16 (2) ◽  
pp. 86-92
Author(s):  
Rafael Penadés ◽  
Bárbara Arias ◽  
Mar Fatjó-Vilas ◽  
Laura González-Vallespí ◽  
Clemente García-Rizo ◽  
...  
Keyword(s):  
Systematic Review ◽  
Dna Methylation ◽  
Mental Disorders ◽  
Epigenetic Modifications ◽  
Symptom Improvement ◽  
Epigenetic Changes ◽  
Main Hypothesis ◽  
Psychological Treatments ◽  
Time Period ◽  
The Impact

Background: Epigenetic modifications appear to be dynamic and they might be affected by environmental factors. The possibility of influencing these processes through psychotherapy has been suggested. Objective: To analyse the impact of psychotherapy on epigenetics when applied to mental disorders. The main hypothesis is that psychological treatments will produce epigenetic modifications related to the improvement of treated symptoms. Methods: A computerised and systematic search was completed throughout the time period from 1990 to 2019 on the PubMed, ScienceDirect and Scopus databases. Results: In total, 11 studies were selected. The studies were evaluated for the theoretical framework, genes involved, type of psychotherapy and clinical challenges and perspectives. All studies showed detectable changes at the epigenetic level, like DNA methylation changes, associated with symptom improvement after psychotherapy. Conclusion: Methylation profiles could be moderating treatment effects of psychotherapy. Beyond the detected epigenetic changes after psychotherapy, the epigenetic status before the implementation could act as an effective predictor of response.

Influence of the ICCPR in Asia

2018 ◽  
Author(s):  
Yogesh Tyagi
Keyword(s):  
Human Rights ◽  
Political Rights ◽  
International Human Rights ◽  
Factors Affecting ◽  
Judicial Discourse ◽  
International Human ◽  
Golden Jubilee ◽  
Civil And Political Rights ◽  
The Impact

The golden jubilee of the International Covenant on Civil and Political Rights (ICCPR) coincides with the emergence of Asia as a centre of global attention. However, greater attention to Asia has been accompanied by some scepticism over its attitude towards human rights. The chapter provides an overall assessment of the impact of the ICCPR on the major Asian States, with an analysis of the factors affecting such influence. The chapter considers the involvement in, observance of, and compliance with the provisions of the ICCPR by these States. It further delves into the academic and judicial discourse on the ICCPR within these States, recording the domestic disposition towards judgments of foreign courts, the output of the Human Rights Committee, and the work of other international human rights bodies. It makes suggestions for developing mechanisms to improve the effectiveness of the ICCPR and for creating databases to perform further research in the area.

scholarly journals Assessing the Impact of Bank Concentration and Liquidity of Refah Bank Branches on Profitability during the Period1383-190

2014 ◽  
Vol 4 (1) ◽  
pp. 248
Author(s):  
Hossin Ostadi ◽  
Nastran Monsef
Keyword(s):  
Commercial Banks ◽  
Bank Capital ◽  
Factors Affecting ◽  
Bank Branches ◽  
Independent Variables ◽  
Bank Deposits ◽  
The Impact ◽  
Bank Concentration ◽  
Research Period

Profitability is an important factor to show this articledoeswhat is the role of the intermediary bank to collect your savings and allocation of loans.  Given the importance of profitability indicators in this study, the factors affecting the profitability of commercial banks in Iranare analyzedwith emphasis on the degree of centralization and bank deposits. Dependent variable is indicators of profitability (ROE, ROA) and bank deposits, bank size, bank capital, focus on liquidity and banking requirements are independent variables. Correlation analysis and OLS regression are used and the research period is 1381 to 1390 that the country's territory where bank branches.Our results indicate that the effect of bank size on profitability is positive and the increase in bank size on profitability is increased. Impact on the profitability of bank deposits is positive, ie increasing the profitability of bank deposits increased. Finally, the impact of bank concentration on profitability is positive. Increasing the bank's focus profitability increases. Moreover, the results adversely affect the liquidity of the index is profit. 

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