scholarly journals The possible negative consequences of underground dam and reservoir construction and operation in coastal karst areas: an example of the HEPP Ombla near Dubrovnik (Croatia)

2013 ◽  
Vol 1 (2) ◽  
pp. 1409-1443
Author(s):  
T. Roje-Bonacci ◽  
O. Bonacci
Keyword(s):  
Karst Aquifer ◽  
Grout Curtain ◽  
Negative Consequences ◽  
Karst Spring ◽  
Environmental Consequences ◽  
Coastal Karst ◽  
Underground Dam ◽  
Reservoir Construction ◽  
The Mean ◽  
Annual Discharge

Abstract. The Ombla Spring represents a typical abundant coastal karst spring located in the vicinity of town of the Dubrovnik (Croatia). Its outlet is at an altitude of 2.5 m above sea level (m a.s.l.) and the water from it immediately flows into the Adriatic Sea. The minimum and maximum measured discharges are 3.96 m3 s−1 and 117 m3 s−1, respectively. The Trebišnjica River traverses through its catchment. The mean annual discharge, after the canalization of over 60 km of its watercourse with spray concrete (in the time span 1981–2011), is 24.05 m3 s−1. Before massive civil engineering work which took place during 1968–1980, the mean annual discharge was 28.35 m3 s−1. There is a project for construction of the hydro electric power plant (HEPP) Ombla, which will exclusively use groundwater from the Ombla Spring karst aquifer. The underground dam will be constructed about 200 m behind the existing karst spring outflow in the karst massif, by injecting a grout curtain. Top of the grout curtain is planned to be at an altitude of 130, m a.s.l. This karst system is complex, sensitive, vulnerable and ecologically extremely valuable. The grout curtain planned to be realized, as well as the HEPP Ombla development, could lead to extremely dangerous technical and environmental consequences. In this paper some potential, but very probable, negative consequences of the HEPP Ombla construction and development are explained.

scholarly journals The possible negative consequences of underground dam and reservoir construction and operation in coastal karst areas: an example of the hydro-electric power plant (HEPP) Ombla near Dubrovnik (Croatia)

2013 ◽  
Vol 13 (8) ◽  
pp. 2041-2052 ◽  
Author(s):  
T. Roje-Bonacci ◽  
O. Bonacci
Keyword(s):  
Power Plant ◽  
Electric Power ◽  
Karst Aquifer ◽  
Grout Curtain ◽  
Negative Consequences ◽  
Karst Spring ◽  
Coastal Karst ◽  
Underground Dam ◽  
The Mean ◽  
Annual Discharge

Abstract. The Ombla Spring represents a typical abundant coastal karst spring located in the vicinity of the town of Dubrovnik (Croatia). Its outlet is at an altitude of 2.5 m above sea level (m a.s.l.) and the water from it immediately flows into the Adriatic Sea. The minimum and maximum measured discharges are 3.96 m3 s−1 and 117 m3 s−1, respectively. The Trebišnjica River traverses through its catchment. The mean annual discharge, after the canalization of over 60 km of its watercourse with spray concrete (in the time span 1981–2011), is 24.05 m3 s−1. Before massive civil engineering work which took place during 1968–1980, the mean annual discharge was 28.35 m3 s−1. There is a project for construction of the hydro-electric power plant (HEPP) Ombla, which will exclusively use groundwater from the Ombla Spring karst aquifer. The underground dam will be constructed about 200 m behind the existing karst spring outflow in the karst massif, by injecting a grout curtain. The top of the grout curtain is planned to be at an altitude of 130 m a.s.l. This karst system is complex, sensitive, vulnerable and ecologically extremely valuable. The grout curtain, as well as the HEPP Ombla development, could lead to extremely dangerous technical and environmental consequences. In this paper some probable, negative consequences of the HEPP Ombla construction and development are explained. The HEPP Ombla could result in many large and hard-to-predict negative consequences which are specific for this particular HEPP, for example (1) severe spring discharge change; (2) unpredictable regional groundwater redistribution; (3) threatening of endemic fauna; (4) induced seismicity; (5) induced sinkholes; (6) occurrence of landslides; (7) conflict regarding internationally shared karst aquifers; (8) intensification of karst flash floods; (9) sea water intrusion in coastal karst aquifer; etc.

Mines in the End Zone: Are there Downsides to Team Performance?

2020 ◽  
Vol 23 ◽  
Author(s):  
Troy V. Mumford ◽  
M. Travis Maynard
Keyword(s):  
Team Performance ◽  
Role Overload ◽  
Future Research ◽  
Negative Consequences ◽  
Regression To The Mean ◽  
Occupational Psychology ◽  
Team Success ◽  
The Mean ◽  
Overconfidence Bias

Abstract Research on teams in organizations tends to focus on understanding the causes of team performance with a focus on how to enjoy the benefits of team success and avoid the negative consequences of team failure. This paper instead asks the question, ‘what are some of the negative consequences of team success?’ A review of the literature on teams is augmented with research from cognitive science, sociology, occupational psychology, and psychology to explore the potential negative long-term consequences of teamwork success. The general topics of groupthink, overconfidence bias, regression to the mean, role overload, and strategy calcification are reviewed while discussing the implications for future research streams and practical team management.

scholarly journals A qualitative exploration of the factors associated with initiation to crystal use in Iran.

2020 ◽  
Author(s):  
Shirin Shahbazi Sighaldeh ◽  
Fatemeh Zarghami ◽  
Ali Shahryari ◽  
Ali Mohammadinia ◽  
Mohsen Ebrahimi ◽  
...  
Keyword(s):  
Public Health ◽  
Addiction Treatment ◽  
Easy Access ◽  
Negative Consequences ◽  
Snowball Sampling ◽  
Crystal Methamphetamine ◽  
Golestan Province ◽  
The Mean ◽  
The Government ◽  
Qualitative Exploration

Abstract Background: Crystal (methamphetamine) is a strong stimulant of addictive substances that affects the central nervous system. The consumption of this substance is increasing among teenagers and adult young people in the country. In this matter, one of the practical and important ways to its control is to identify the factors leading to its first use. Thus this paper, explores the factors related to the first crystal use in Golestan province, Iran.Methods: In a qualitative study, 19 crystal users were recruited in the study conducted in Golestan province by snowball sampling from DIC (Drop-In Center) in addiction treatment centers. The interviews were mostly carried out individually with the participants; only one interview was conducted in an addiction treatment camp in the form of a group-focused discussion. Data analysis was implemented through content analysis in MAXQDA 10 software.Results: The mean age of the participants was 35.05± 6.06 years with a range of 23-46 years. Meanwhile, the mean of crystal use period was 7.42 (SD:3.61) and a range of 1-14 years. Based on the obtained data, the reasons for first crystal use could be categorized in six; 1: "crystal use to other drugs rehabilitation"; 2: "Lack of awareness of the addictive nature of crystal"; 3: “stimulating curiosity in public with crystal-use friends” , 4: affordable and convenient use”, 5: "anti-sleeping effects and increasing work efficiency", and 6: "therapeutic and other misconceptions”".Conclusions: The results indicated that crystal is mostly abused to opium rehabilitation. The lack of awareness and misconceptions about this substance can lead people to crystal use. Therefore, designing public health interventions to increase awareness about negative consequences of crystal use is fundamental to prevent people from abusing it. We suggest designing public health program to promote awareness about health risks of crystal and modifying related misconceptions. Finally, the government can establish policies to mandate sale tax for crystal producers and reduce easy access to crystal especially among youth.

scholarly journals Analyses of Monthly Discharges in Slovakia Using Hydrological Exploratory Methods

Proceedings ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 18
Author(s):  
Mária Ďurigová ◽  
Dominika Ballová ◽  
Kamila Hlavčová
Keyword(s):  
Change Points ◽  
Hydrological Data ◽  
Pettitt Test ◽  
The Mean ◽  
Monthly Discharge ◽  
Meteorological Elements ◽  
The Relationship ◽  
Annual Discharge ◽  
Hydrological Regimes

Detailed analyses of hydrological data are necessary in order to prove changes in their character. This article focuses on an analysis of the average monthly discharges of 14 stage-discharge gauging stations in Slovakia. The measured period is from 1931 to 2016. The approaches used are hydrological exploration methods, which were created by hydrologists to describe the behavior of hydrological time series. The methods are used to identify a change-point using an analysis of any residuals, the Pettitt test, and an analysis of the relationship between the mean annual discharge deviations from the long-term annual discharge and the deviations of the average monthly discharge from the long-term average monthly discharge. A considerable number of change-points were identified in the 1970s and 1980s. The results of the analyses show changes in the hydrological regimes, but to confirm the accuracy of the outcomes, it is also necessary to examine other hydrological and meteorological elements such as, e.g., precipitation and the air temperature.

scholarly journals Performance indicators in higher education with learning analytics

2017 ◽  
Vol 3 (2) ◽  
pp. 12
Author(s):  
Carlos Morais ◽  
Paulo Alexandre Alves ◽  
Luisa Miranda
Keyword(s):  
Virtual Environment ◽  
Learning Process ◽  
Learning Analytics ◽  
Teaching And Learning ◽  
Virtual Learning ◽  
Virtual Learning Environment ◽  
Negative Consequences ◽  
Access Frequency ◽  
The Mean ◽  
Academic Information

The regular use of virtual learning environments by educational institutions and the availability of large quantities of data regarding the teaching and learning process both challenge teachers, institutions and researchers to explore such data within the perspective of learning analytics in order to obtain indicators which might contribute to the improvement of the teaching and learning process. Consequently, such improvement may lead to students’ better learning outcomes as well as a better relationship with the institution they attend. Taking into account that student retention and dropout from degree courses before their completion have highly negative consequences for a high number of students, the aim of this research is to look into indicators associated with such problems through a mixed methodology, both qualitative and quantitative, and through procedures of analysis and research of data from databases containing academic information provided by a sample of 1,588 undergraduates. The focus of the study lies upon the relation and analysis of the following variables: students’ frequency of access per course unit to the virtual environment of the institution they attend; quantity of course units passed; and mean of the marks obtained in the course units passed. Among the results obtained, we highlight the existence of a positive degree of association with moderate correlation between the variables frequency of access per course unit to the virtual environment and the mean of the number of course units passed. Following the division of the sample into four different groups, each group corresponding to one quartile, resulting from the data regarding the frequency of accesses per course unit to the institution’s virtual environment, significant differences were found concerning the mean of the course units passed between the groups showing a higher frequency of access to the virtual learning environment and those with a lower access frequency, to the advantage of the groups showing a higher frequency of access to the virtual environment. Therefore, considering the way the groups were constituted, there is proof that the higher the frequency of access to the virtual environment is, the higher the probability of students succeeding in the course units they attend will be.

scholarly journals Impact of Cognitive Dysfunction in the Middle East Depressed Patients: The ICMED Study

2018 ◽  
Vol 14 (1) ◽  
pp. 270-283 ◽  
Author(s):  
Abdulqader Al Jarad ◽  
Ahmad Al Hadi ◽  
Ali Al Garatli ◽  
Aly Akram ◽  
Dakhil Alsaeidi ◽  
...  
Keyword(s):  
Cognitive Dysfunction ◽  
United Arab Emirates ◽  
Rating Scale ◽  
Common Factor ◽  
High Rate ◽  
Negative Consequences ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
The Mean ◽  
The Impact

Background:Major depressive disorder is a common condition with a high rate of recurrence, chronicity, and affecting economic burden, including disability in the workplace, which leads to negative consequences on both individuals and society.Objectives:This study aimed to estimate the impact of cognitive dysfunction, as declared by the patient, on performing daily tasks/activities among patients with major depression disorder (MDD).Methods:This investigation is based on multinational cross-sectional survey of 499 workers recruited from the Kingdom of Saudi Arabia (KSA) and United Arab Emirates (UAE). We assessed the severity of depression by Hamilton Depression Rating Scale (HDRS). Impact of Depression in the Workplace in Europe Audit (IDEA) survey and trial making test (TMT) parts A and B were used to assess the impact of cognitive dysfunction on performing daily tasks/activities in adult patients presented with MDD.Results:A total of 499 persons were included in this study, aged 18–66 years, current workers and managers. Of them, 17.8% were normal (remitted), 22.4% were mildly depressed, 23.4% were moderately depressed, 8.6% were severely depressed, and 27.7% were very severely depressed at the time of the study according to HDRS. Common symptoms attributable to depression were low mode or sadness (89.8%), followed by insomnia (75.2%) and crying (70.9%). Of them, low mode or sadness was the most common factor affecting the work performance (90.2%). About 66.3% of participants diagnosed with depression by a doctor/medical professional. Awareness of the disease was recognizable by patients’ managers in only 31.9% of the cases. Furthermore, 45.3% of cases had taken off work due to depression with mean duration of 38.7 (95% CI 37.7 to 39.7) days. The mean TMT parts A and B score were 69.2 (95% CI 66.3 to 72.2) and 126.6 (95% CI 121 to 132), respectively. Lastly, a significant positive correlation between the mean score for HDRS and TMT-A and B scores was observed.Conclusion:Depression affects work productivity and work environment with negative consequences to countries’ economy. Awareness of depression in the workplace in KSA and UAE is still suboptimal. The personal and societal burden of this issue cannot be neglected when we become aware of the proportion of affected people.

scholarly journals Calibration of a semi-distributed lumped karst system model and analysis of its sensitivity to climate conditions: the example of the Qachqouch karst spring (Lebanon)

2020 ◽  
Author(s):  
Emmanuel Dubois ◽  
Joanna Doummar ◽  
Séverin Pistre ◽  
Marie Larocque
Keyword(s):  
Time Series ◽  
Karst Aquifer ◽  
Regulatory Function ◽  
Karst Aquifers ◽  
Karst Spring ◽  
Flow Rates ◽  
Lumped Model ◽  
Climate Conditions ◽  
Time Series Analyses ◽  
Spring Flow

Abstract. Flow in complex karst aquifers is challenging to conceptualize, therefore to model for better management practices, especially in poorly investigated areas, in semi-arid climates, and under changing climatic conditions. The objective of this work is to propose a calibration approach based on time-series analyses for a karst aquifer and to assess the impact of changing climate conditions on the spring discharge. Based on more than three years of high-resolution continuous monitoring, a semi-distributed lumped model was calibrated and validated for the Qachqouch karst spring, north of Beirut (Lebanon). Time-series analyses and decomposition of spring hydrographs revealed that the system has a high regulatory function, with considerable storage capacity providing stable flow (minimum flow of 0.2 m3/s) during the dry season, and with flow rates exceeding 10 m3/s during the wet season, similar to other karst aquifers in the region. Based on this detailed understanding of the hydrodynamics of the system, the model geometry and parameters were validated. Three linear reservoirs were implemented to reproduce the combined contribution of the different flow components of the system. A satisfactory simulation (Nash–Sutcliffe coefficient = 0.72) of measured spring flow rates was obtained after calibration. Climate change conditions (+1 to +3 °C warming, −10 to −30 % less precipitation annually, and intensification of rain events) were added to a baseline climatic year to produce scenarios of expected spring flow responses. Results show that the Qachqouch karst aquifer is sensitive to decreasing rainfall, which is associated with more pronounced recessions, with flow rates decreasing by 34 % and 1-month longer dry periods. Because of the limited influence of snow on the spring flow rate, a warming climate has less impact on spring flow conditions than a reduction in precipitation. Although the model shows that increasing rainfall intensity induces larger floods, recessions and shorter low flow periods, the real impact of high-intensity precipitation events remains uncertain, since the model does not account for complex unsaturated and epikarst processes. This work shows that calibrating a semi-distributed lumped model using time series analysis can be an efficient approach to improve simulations of complex karst aquifers, thus providing useful models for long-term sustainable water management.

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