scholarly journals Multi-Criteria Performance Evaluation of Gridded Precipitation and Temperature Products in Data-Sparse Regions

Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1597
Author(s):  
Ibrahim Mohammed Lawal ◽  
Douglas Bertram ◽  
Christopher John White ◽  
Ahmad Hussaini Jagaba ◽  
Ibrahim Hassan ◽  
...  
Keyword(s):  
Decision Making ◽  
Performance Metrics ◽  
Research Unit ◽  
Climate Data ◽  
Meteorological Forcing ◽  
Lake Chad ◽  
Climate Research ◽  
Princeton University ◽  
Lake Chad Basin ◽  
Precipitation And Temperature

Inadequate climate data stations often make hydrological modelling a rather challenging task in data-sparse regions. Gridded climate data can be used as an alternative; however, their accuracy in replicating the climatology of the region of interest with low levels of uncertainty is important to water resource planning. This study utilised several performance metrics and multi-criteria decision making to assess the performance of the widely used gridded precipitation and temperature data against quality-controlled observed station records in the Lake Chad basin. The study’s findings reveal that the products differ in their quality across the selected performance metrics, although they are especially promising with regards to temperature. However, there are some inherent weaknesses in replicating the observed station data. Princeton University Global Meteorological Forcing precipitation showed the worst performance, with Kling–Gupta efficiency of 0.13–0.50, a mean modified index of agreement of 0.68, and a similarity coefficient SU = 0.365, relative to other products with satisfactory performance across all stations. There were varying degrees of mismatch in unidirectional precipitation and temperature trends, although they were satisfactory in replicating the hydro-climatic information with a low level of uncertainty. Assessment based on multi-criteria decision making revealed that the Climate Research Unit, Global Precipitation Climatology Centre, and Climate Prediction Centre precipitation data and the Climate Research Unit and Princeton University Global Meteorological Forcing temperature data exhibit better performance in terms of similarity, and are recommended for application in hydrological impact studies—especially in the quantification of projected climate hazards and vulnerabilities for better water policy decision making in the Lake Chad basin.

scholarly journals Predicted and Projected Water Resources Changes in the Chari Catchment, the Lake Chad Basin, Africa

2020 ◽  
Vol 21 (1) ◽  
pp. 73-91 ◽  
Author(s):  
Rashid Mahmood ◽  
Shaofeng Jia ◽  
Tariq Mahmood ◽  
Asif Mehmood
Keyword(s):  
Water Resources ◽  
Tropical Rainfall Measuring Mission ◽  
Baseline Period ◽  
Research Unit ◽  
Low Flow ◽  
Climatic Research Unit ◽  
Climatic Data ◽  
Lake Chad ◽  
Lake Chad Basin ◽  
Almost All

AbstractThe water resources of the Chari River basin, contributing more than 90% of the water to one of the largest lakes in Africa, known as Lake Chad, are highly vulnerable to natural and anthropogenic changes. Therefore, the changes in water resources were predicted for the next 20 years (i.e., 2016–35) by using the harmonic regression model (HRM), one of the most sophisticated time series methods, and also projected under representative concentration pathways (RCPs) by using the multimodel approach for the periods 2021–50, 2051–80, and 2081–2100, with respect to the baseline period (1971–2001). The Tropical Rainfall Measuring Mission (TRMM), Climatic Research Unit (CRU), and dynamically downscaled climatic data were used in the analysis of the present study. The results showed that under MME-RCP2.6 (multimodel ensemble of RCMs), low flow (average of low-flow months, December–July), high flow (August–November), and annual flow were projected to decrease in the future. In contrast, under MME-RCP4.5 and MME-RCP8.5, high and annual flows were projected to increase in all three time horizons, while low flow will decrease except in 2021–50 under MME-RCP8.5. In the next two decades, the HRM showed decrease in all type of flows (low, high, and annual), very similar to the results under MME-RCP2.6 for the same period. In contrast, almost all flows are expected to increase under MME-RCP4.5 and MME-RCP8.5 in the next two decades. On the whole, the flows are expected to decrease under the HRM and RCP2.6 but to increase under RCP4.5 and RCP8.5.

scholarly journals Biomass Burning and Water Balance Dynamics in the Lake Chad Basin in Africa

Earth ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 340-356
Author(s):  
Forrest W. Black ◽  
Jejung Lee ◽  
Charles M. Ichoku ◽  
Luke Ellison ◽  
Charles K. Gatebe ◽  
...  
Keyword(s):  
Water Balance ◽  
Biomass Burning ◽  
Water Cycle ◽  
Potential Evapotranspiration ◽  
Southern Oscillation ◽  
Wet Season ◽  
Lake Chad ◽  
Chad Basin ◽  
Lake Chad Basin ◽  
Logone Catchment

The present study investigated the effect of biomass burning on the water cycle using a case study of the Chari–Logone Catchment of the Lake Chad Basin (LCB). The Chari–Logone catchment was selected because it supplies over 90% of the water input to the lake, which is the largest basin in central Africa. Two water balance simulations, one considering burning and one without, were compared from the years 2003 to 2011. For a more comprehensive assessment of the effects of burning, albedo change, which has been shown to have a significant impact on a number of environmental factors, was used as a model input for calculating potential evapotranspiration (ET). Analysis of the burning scenario showed that burning grassland, which comprises almost 75% of the total Chari–Logone land cover, causes increased ET and runoff during the dry season (November–March). Recent studies have demonstrated that there is an increasing trend in the LCB of converting shrubland, grassland, and wetlands to cropland. This change from grassland to cropland has the potential to decrease the amount of water available to water bodies during the winter. All vegetative classes in a burning scenario showed a decrease in ET during the wet season. Although a decrease in annual precipitation in global circulation processes such as the El Niño Southern Oscillation would cause droughts and induce wildfires in the Sahel, the present study shows that a decrease in ET by the human-induced burning would cause a severe decrease in precipitation as well.

Numerical Simulation of Heat Exchanges for a Desert House Type ADRAR

2017 ◽  
Vol 24 ◽  
pp. 63-75 ◽  
Author(s):  
A. Oudrane ◽  
B. Aour
Keyword(s):  
Ambient Temperature ◽  
Thermal Inertia ◽  
Research Unit ◽  
Meridian Plane ◽  
Algebraic Equations ◽  
Climate Data ◽  
Nodal Method ◽  
Recent Climate ◽  
Wind Exposure ◽  
Heat Exchanges

The main objective of this work is to study the thermal exchanges in a habitable enclosure located in a desert region of Algeria (Adrar). This latter is considered as an air volume of parallelepiped shape limited by horizontal and vertical flat walls. The walls are the only capacitive elements of the enclosure. They are thermally coupled by convection and radiation and are the seat of conductive flux. The external facades of the enclosure are the seat of a convective flux with the external air and radiative exchanges with the environment (ground and sky). Openings (cracks, sealing defects, infiltration orifices, renewal orifices, etc.) allow the air to circulate inside the habitable enclosure and between the inside and the outside. Thermal exchanges are studied using the balance equations established at each wall of the enclosure. These equations have been discretized by an implicit finite difference method. The systems of algebraic equations thus obtained have been solved by the Gauss algorithm using the nodal method. The effects of the outdoor ambient temperature, the density of the incident solar flux on the facades and the orientation of the habitable enclosure in the meridian plane on the temperature distributions of the internal walls and the filled air in the enclosure havec been analyzed on the basis of recent climate data measured at the ADRAR Saharan Renewable Energy Research Unit. An analysis of the evolution of the internal ambient temperature as a function of the wind exposure factor of the heated space and of the degree of leaktightness of the doors and windows was also carried out at the end of this work. An acceptable agreement was found between the numerical results and those measured by the radiometric station. Moreover, the results obtained show that the building material used in this region causes undesirable overheating due to its thermal inertia.

Employees as a vector of strategic intent: an examination of corporate, social and environmental strategic intent recognition by employees

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Pat Auger ◽  
Timothy M. Devinney ◽  
Grahame Dowling
Keyword(s):  
Decision Making ◽  
Environmental Sustainability ◽  
Corporate Strategy ◽  
Performance Metrics ◽  
Methodological Approach ◽  
Environmental Strategy ◽  
Content Type ◽  
Strategic Intent ◽  
Csr Strategy ◽  
Corporate Social

PurposeOne of the hallmarks of strategizing is having a clearly articulated vision and mission for the organization. It has been suggested that this provides a compass bearing for the organization's strategy, helps in motivation, commitment and retention of employees, serves as a guide to internal sensemaking and decision-making, has a potential performance effect, helps establish the identity of the organization and positions its desired reputation. The compass bearing role is important because it guides the selection of the goals and strategic orientation of the organization which in turn shapes its overall strategy and much of its internal decision making. The inspirational role is important because it helps to motivate and engage employees and other stakeholders.Design/methodology/approachThis study provides a more rigorous indication as to whether employees can, in the first instance, recognize and distinguish their corporate and environmental strategy from that of their competitors within their own industry and random other companies from other industries. This first issue addresses, to a degree, if and why, such strategic communiqués are effective inside a range of different organizations. Secondly, the authors examine whether there are any specific individual level effects that could explain variations in these responses. Finally, the authors examine the extent to which the recognition rates the authors observe, relate to how employees are rewarded through appraisals, promotions and salary increases. This helps in the authors’ understanding of the role of hard incentives versus soft motivations. The authors’ approach to assessing employee knowledge of their organization's strategy is unique. Rather than survey employees about their knowledge, the authors use a matching study and a discrete choice measurement model to assess if they can recognize their organization's strategy from those of their competitors and some other randomly selected organizations. This approach allows us to mitigate social desirability and common method biases and directly estimate the underlying behavioral model being used to assess their organization's strategy.FindingsOverall, the authors found that few employees could correctly identify their corporate strategy statements. In the case of corporate strategy statements, the authors find that, on average, only 29 percent of employees could correctly match their company to its publicly espoused corporate strategy. When the authors look at the environmental sustainability strategy of the firm, this is worse overall, with individuals doing no better than random on average. When the authors look at company training and communication practices across the realm of different strategies, the authors see a number of factors leading to the general results. First, most of the authors’ respondents could not recall a significant effort being given to communication and training by their employer. Indeed, most communication/training is simply related to having documentation/brochures available. Second, respondents indicated that more effort is put into communicating corporate strategy to employees in a more systematic manner than communication about environmental/corporate social responsible (CSR) strategy. Third, the authors see that individuals are evaluated more on and give more weight to, evaluations relating to their ability to meet individual/group financial and market performance metrics (targets) and work as a team than their involvement in environmental and social responsibility programs. Finally, the employees studied seemed to be more confident in understanding the corporate strategy. When asked to put their corporate strategy into words – a task the authors asked respondents to do after the matching phase of the study – 40% of participants did so for the corporate strategy but only 14% did so for the environmental strategy and seven percent for the CSR strategy.Practical implicationsThe primary implication of the study is that the values-mission-strategy logic of strategic motivation seems to have limited validity and with respect to the view that employees are a vector of corporate strategy. It is hard to argue that employees can be a vector for something they cannot recall or even distinguish between.Originality/valueThe study is unique in terms of (1) asking the very simple question of whether employees internalize their company's strategies and (2) in the methodological approach to examine employee knowledge and informativeness.

Schließen mit Erfahrungssätzen

2021 ◽  
Author(s):  
Paola Janßen
Keyword(s):  
Decision Making ◽  
Research Unit ◽  
Prima Facie ◽  
Economic Research ◽  
Court Decisions ◽  
Applied Statistics ◽  
Conditional Probabilities ◽  
Empirical Methods ◽  
Legal Decision Making ◽  
The University

When dealing with experiential sentences in court, there is a risk of committing the probabilistic inverse fallacy, the swapping of conditional probabilities. Such a fallacy can be serious in legal decision making. Using empirical methods, the dissertation shows that this fallacy can be observed in civil procedural court decisions in which prima facie evidence is used and can have a significant impact on decision making. The dissertation was written at the Research Unit "Statistics in Court" of the Chair of Empirical Economic Research and Applied Statistics at the University of Bremen.

Selection methods of lean management tools: a review

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ali Jaber Naeemah ◽  
Kuan Yew Wong
Keyword(s):  
Decision Making ◽  
Performance Metrics ◽  
Work Conditions ◽  
Lean Management ◽  
Selection Methods ◽  
Tool Selection ◽  
Content Type ◽  
Customer Complaints ◽  
Lean Tools ◽  
Selection Of

PurposeThe purpose of this paper is (1) to review, analyze and assess the existing literature on lean tools selection studies published from 2005 to 2021; (2) to identify the limitations faced by previous studies; and (3) to suggest future works that are necessary to facilitate the selection of lean tools.Design/methodology/approachA systematic approach was used in order to identify, collect and select the articles. Several keywords related to the selection of lean tools were used to collect articles from different Scopus indexed journals. Next, the study systematically reviewed and analyzed the selected papers to identify the lean tools' selection method and discussed its features and limitations.FindingsAn analysis of the results showed that previous studies have adopted two types of methods for selecting lean tools. First, there are various traditional methods being used. Second, multi-criteria decision-making (MCDM) methods were commonly used in previous studies, such as the multi-objective decision-making method (MODM), single multi-attribute decision-making (MADM) methods and hybrid (MCDM). Moreover, the study revealed that the lean tools' selection methods in previous studies were based on evaluating the relationship between either lean tools and performance metrics or lean tools and waste, or both.Research limitations/implicationsIn terms of its theoretical value, the study is considered as an extension of the previous researches performed on this topic by determining and analyzing the features of the most selection methods of lean tools. Unlike previous review papers, this review had considered discussing and analyzing the characteristics and limitations of these methods. Section 2.2 of this paper reviewed some of the categories of MCDM methods as well as some of the traditional methods used in the selected previous studies. Section 2.1 of this paper explained the concept of lean management and its application benefits. Further, only three sectors were covered by the previous studies in this review paper. This study also provided recommendations for future research. Therefore, it provided researchers with a good conception of how to conduct the studies on lean tools selection. Besides, knowing the methods used in previous studies can help researchers develop new methods to select the best set of lean tools. That is, this study provided and advanced the existing knowledge base for researchers concerning lean tools selection, especially there is limited availability of review papers on this topic. Moreover, the study showed researchers the importance of the relationship between lean tools and indicators or/and performance indicators to determine the appropriate set of lean tools so that the results of future studies will be more realistic and acceptable.Practical implicationsPractically, manufacturers face a significant challenge when selecting proper lean tools. This study may enhance managers, manufacturers and company's knowledge to identify most of the methods used to choose the best set of lean tools and what are the advantages, disadvantages and limitations of these methods as well as the latest studies that have been adopted in this topic. That means this study can direct companies to prioritize the application of lean tools depending on either the manufacturing performance metrics or/and manufacturing wastes so that they avoid incorrect application of lean tools, which will add more non-value added activities to operations. Therefore companies can decrease the time and cost losses and enhancing the quality and efficiency of the performance. Correctly implementing the best set of lean tools in companies will lead in general to correctly applying lean management in corporations. Therefore, these lean tools can boost the economic aspect of companies and society through reducing waste, improving performance indicators, preserving time and cost, achieving quality, efficiency, competitiveness, boosting employee income and improving the gross domestic product. The correct lean tool selection reduces customer complaints and employee stress and improves work conditions, health, safety and labor wellbeing. Besides, the correct lean tools selection improves materials usage, energy usage, water usage and decreases liquid wastes, solid wastes and air emissions. As a result, the right selection of lean tools will have positive effects on both the environment and society. The study may also encourage manufacturers and researchers to adopt studies on lean tools selection in small- and medium-sized companies because the study referred to the importance and participation of these kinds of companies in a large proportion of the economy of developing countries. Further, the study may encourage some countries that have not previously adopted this type of study, academically and industrially to conduct lean tools selection studies.Social implicationsAs mentioned previously, the correct lean tool selection reduces customer complaints and employee stress and improves work conditions, health, safety and labor wellbeing. The proper lean tools selection improves materials usage, energy usage, water usage and decreases liquid wastes, solid wastes and air emissions. As a result, the right choice of lean tools will positively affect both the environment and society.Originality/valueThe study expanded the efforts of previous studies concerning lean management features. It provided an accurate review of most lean tools selection studies published from 2005 to 2021 and was not limited to the manufacturing sector. It further identified and briefly described the selection methods concerning lean tools adopted in each paper.

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