bluuebunny/crossref_metadata_2025 huggingface dataset:
Entrepreneurial Leadership and Sustainable Performance of Manufacturing SMEs in Malaysia: The Contingent Role of Entrepreneurial Bricolage
Authors: Nor-Aishah Hassan , Ahmad Noor Hazlina , Thurasamy Ramayah
Published: April 2020

The purpose of this research is to delve into the effect of entrepreneurial leadership (EL) on the economic, environmental, and social aspects of sustainable performance; the research also focuses on the contingency role of entrepreneurial bricolage (EB). The increasing concern focused on the triple bottom line (TBL) issues has triggered enthusiasm and inspiration in the field of sustainable entrepreneurship, especially amongst the small medium enterprise (SME) owners or leaders who are directly responsible for organizational sustainable performance. This research examines the relationships between EL and economically sustainable performance (ECSPF), environmentally sustainable performance (ENSPF), and social sustainable performance (SOSPF); these relationships are contingent upon EB through the lens of Upper Echelons Theory (UET) and Effectuation Theory (ET). A total of 146 responses from a cross-sectional survey from Malaysian manufacturing SMEs were investigated using Partial Least Squares-Structural Equation Modeling (PLS-SEM). The findings reveal that EL has significant effects on ENSPF and SOSPF, but has an insignificant effect on ECSPF. Meanwhile, EB does not play the contingent role in strengthening the relationships between EL and ECSPF, EL and ENSPF, and EL and SOSPF. This research highlights the importance of EL and shows that SME owners or leaders should embrace and develop their skills as a crucial step towards achieving sustainable performance for their companies. The implications and limitations of the research are discussed and recommendations for future research are also presented.
Sustainable Solar Energy in Mexican Universities. Case Study: The National School of Higher Studies Juriquilla (UNAM)
Authors: Hernandez-Escobedo Quetzalcoatl , Ramirez-Jimenez Alida , Dorador-Gonzalez Jesús Manuel , Perea-Moreno Miguel-Angel , Perea-Moreno Alberto-Jesus
Published: April 2020

Universities around the world should be at the forefront of energy-saving and efficiency processes, seeking to be at the same level or preferably higher than the rest of society, and seeking the goal of 20% renewable energy by 2020. Sustainability practices have been carried out by several universities. In Mexico, the National Autonomous University of Mexico (UNAM) is a leader in this subject; in fact, the newest National School of Higher Studies - Juriquilla (ENES-J) that belongs to UNAM, located in the city of Queretaro (Mexico), is involved in its sustainability plan, with one of its main objectives being to save electric energy. UNAM has some campuses outside of Mexico City, and one of them is the National School of Higher Studies Juriquilla (ENES-J) in the state of Queretaro, where there is the Orthotics and Prosthetics Laboratory (OPL), in which has been installed a Computer Numerical Control (CNC) machine type Haas Automation model UMC-750, which has 5-axis and is an effective means to reduce the number of setups and increase accuracy for multi-sided and complex parts. This machine will be used to design, build, and assess human prosthesis. This study aimed to contribute to sustainability policies at the ENES-J from UNAM, implementing a solar photovoltaic system (PVS) to deliver electricity to the grid and contribute to reducing the electricity load at the Orthotics and Prosthetics Laboratory (OPL), as well to propose new research lines to support the sustainability policies in universities, and also proposing a financial analysis. To achieve this, in an area of 96.7 m2, 50 solar panels type mono-Si Advance Power API-M330 with an efficiency of 17.83% and a capacity factor of 20.4% will be installed and will provide 17.25 kW of power and 345 kWh of energy. The financial analysis shows the initial costs of 46,575 USD/kW, operation and maintenance (O&M) costs (savings) of 569 USD/kW-year, a monthly electricity export rate of 0.10 USD/kWh, electricity exported to the grid of 21.5 MWh, and an electricity export revenue of 2,145 USD. To assess the environmental balance with this PVS at ENES-J, an analysis of greenhouse gases (GHG) is carried out by using the RETScreen software. In this analysis, a GHG emission factor of 0.45 tCO2/MWh was found, as well as a savings of 12,089 USD per year.
Affordable Housing vs. Urban Land Rent in Widespread Settlement Areas
Authors: Berto Raul , Cechet Giovanni , Stival Carlo Antonio , Rosato Paolo
Published: April 2020

Social housing constitutes a partial response to the demand for affordable housing. In Europe, there are different forms of social housing, which are distinguishable based on whether they employ a universal or residual approach. The latter is employed by Italian initiatives for social residential construction, the financial instrument of which is the Investment Fund for Housing, a closed-end fund managed by CDP (Cassa Depositi e Prestiti) Investment, which provides public–private partnerships. The main obstacle to the supply of low-cost houses is the high cost of building areas or, in other words, the high urban land rent. The value of building areas is particularly high in urban areas and in widespread settlement areas, for instance, in Northeastern Italy. The main objective of this paper is to identify the trade-off between urban land rent and housing affordability in a social housing intervention in Pordenone (Northeastern Italy). Four different scenarios are developed, the variables of which are: Cost of the area (urban rent), cost of construction works (quality of the buildings), and household income distribution. The results show that achieving the economic and social objectives of a social housing investment simultaneously is not possible in any of the scenarios evaluated. To allow the social groups most in need to access affordable housing would require a reduction of approximately 30% of the estimated cost of a building area.
Valuation of Wetland Ecosystem Services in National Nature Reserves in China’s Coastal Zones
Authors: Li Xiaowei , Yu Xiubo , Hou Xiyong , Liu Yubin , Li Hui , Zhou Yangming , Xia Shaoxia , Liu Yu , Duan Houlang , Wang Yuyu , Dou Yuehan , Yang Meng , Zhang Li
Published: April 2020

Wetlands provide ecosystem services for regional development, and, thus, have considerable economic value. In this study, a combination of evaluation methods was carried out to evaluate the wetland ecosystem services provided by national nature reserves in 11 coastal provinces/municipalities in China. We constructed a literature database containing 808 observations (over 170 papers) on field-scale research for wetlands in China’s coastal zones. Using this literature database, as well as land use (LU) data, net primary productivity (NPP), and statistical data, and digital elevation model (DEM) data, we established a valuation framework and database for nine important ecosystem services of the 13 wetland types in the study area. After the large-scale academic literature review, the ordinary kriging offered by Geostatistical Analyst tools was used to interpolate the physical dimensions of the unmeasured locations. The results showed that: 1) the wetland ecosystem services in 35 national nature reserves have a total value of 33.168 billion USD/year; 2) the values of wetland ecosystem services revealed considerable spatial variability along China’s coastal zones; and 3) assessments provide additional insights into the trade-offs between different ecosystem services and wetland types. The valuation framework and database established in this study can contribute to the mapping of wetland ecosystem services in coastal zones.
The Effect of Fractional Time Derivative of Bioheat Model in Skin Tissue Induced to Laser Irradiation
Authors: Hobiny Aatef , Alzahrani Faris , Abbas Ibrahim , Marin Marin
Published: April 2020

This work uses the “fractional order bio-heat model” (Fob) model of heat conduction to offer a new interpretation to study the thermal damages in a skin tissue caused by laser irradiation. The influences of fractional order and the thermal relaxation time parameters on the temperature of skin tissue and the resulting thermal damage are studied. In the Laplace domain, the analytical solutions of temperature are obtained. Using the equation of Arrhenius, the resulting thermal injury to the tissues is assessed by the denatured protein ranges. The numerical results of the thermal damages and temperature are presented graphically. A parametric analysis is dedicated to the identifications of suitable procedures for the selection of significant design variables to achieve an effective thermal in the therapy of hyperthermia.
Using Behavioral Instability to Investigate Behavioral Reaction Norms in Captive Animals: Theoretical Implications and Future Perspectives
Authors: Cathrine Linder Anne , Gottschalk Anika , Lyhne Henriette , Gade Langbak Marie , Hammer Jensen Trine , Pertoldi Cino
Published: April 2020

Behavioral instability is a concept used for indicating environmental stress based on behavioral traits. This study investigates the possibility of using behavioral instability as a tool for assessing behavioral reaction norms in captive animals. The understanding of personality in captive animals can be a useful tool in the development of enrichment programs in order to improve animal welfare. In this study, a case study examined how olfactory stimuli affected the behavior of two polar bears Ursus maritimus in captivity. Using continuous focal sampling throughout the day, it was found that for many behaviors, the individuals responded differently to stimuli, indicating that there was a difference in behavioral reaction norms. This is shown using multiple approaches. One approach used traditional methods for behavioral analyses, and the other approach used the concept of behavioral instability as a new quantitative method. This study demonstrates the utility of behavioral instability as a new quantitative method for investigating behavioral reaction norms, expanding the possibility of comparing behavioral responses between species. Moreover, it is shown that outliers—that cause asymmetric distributions—should not be removed in behavioral analysis, without careful consideration. In conclusion, the theoretical implications and future perspectives of behavioral instability are discussed.
Comparisons of Diverse Machine Learning Approaches for Wildfire Susceptibility Mapping
Authors: Gholamnia Khalil , Gudiyangada Nachappa Thimmaiah , Ghorbanzadeh Omid , Blaschke Thomas
Published: April 2020

Climate change has increased the probability of the occurrence of catastrophes like wildfires, floods, and storms across the globe in recent years. Weather conditions continue to grow more extreme, and wildfires are occurring quite frequently and are spreading with greater intensity. Wildfires ravage forest areas, as recently seen in the Amazon, the United States, and more recently in Australia. The availability of remotely sensed data has vastly improved, and enables us to precisely locate wildfires for monitoring purposes. Wildfire inventory data was created by integrating the polygons collected through field surveys using global positioning systems (GPS) and the data collected from the moderate resolution imaging spectrometer (MODIS) thermal anomalies product between 2012 and 2017 for the study area. The inventory data, along with sixteen conditioning factors selected for the study area, was used to appraise the potential of various machine learning (ML) methods for wildfire susceptibility mapping in Amol County. The ML methods chosen for this study are artificial neural network (ANN), dmine regression (DR), DM neural, least angle regression (LARS), multi-layer perceptron (MLP), random forest (RF), radial basis function (RBF), self-organizing maps (SOM), support vector machine (SVM), and decision tree (DT), along with the statistical approach of logistic regression (LR), which is very apt for wildfire susceptibility studies. The wildfire inventory data was categorized as three-fold, with 66% being used for training the models and 33% being used for accuracy assessment within three-fold cross-validation (CV). Receiver operating characteristics (ROC) was used to assess the accuracy of the ML approaches. RF had the highest accuracy of 88%, followed by SVM with an accuracy of almost 79%, and LR had the lowest accuracy of 65%. This shows that RF is better suited for wildfire susceptibility assessments in our case study area.
Fractional Levy Stable and Maximum Lyapunov Exponent for Wind Speed Prediction
Authors: Duan Shouwu , Song Wanqing , Cattani Carlo , Yasen Yakufu , Liu He
Published: April 2020

In this paper, a wind speed prediction method was proposed based on the maximum Lyapunov exponent (Le) and the fractional Levy stable motion (fLsm) iterative prediction model. First, the calculation of the maximum prediction steps was introduced based on the maximum Le. The maximum prediction steps could provide the prediction steps for subsequent prediction models. Secondly, the fLsm iterative prediction model was established by stochastic differential. Meanwhile, the parameters of the fLsm iterative prediction model were obtained by rescaled range analysis and novel characteristic function methods, thereby obtaining a wind speed prediction model. Finally, in order to reduce the error in the parameter estimation of the prediction model, we adopted the method of weighted wind speed data. The wind speed prediction model in this paper was compared with GA-BP neural network and the results of wind speed prediction proved the effectiveness of the method that is proposed in this paper. In particular, fLsm has long-range dependence (LRD) characteristics and identified LRD by estimating self-similarity index H and characteristic index α. Compared with fractional Brownian motion, fLsm can describe the LRD process more flexibly. However, the two parameters are not independent because the LRD condition relates them by αH > 1.
On the Metric Dimension of Arithmetic Graph of a Composite Number
Authors: Rehman Shahid ur , Imran Muhammad , Javaid Imran
Published: April 2020

This paper is devoted to the study of the arithmetic graph of a composite number m, denoted by A m . It has been observed that there exist different composite numbers for which the arithmetic graphs are isomorphic. It is proved that the maximum distance between any two vertices of A m is two or three. Conditions under which the vertices have the same degrees and neighborhoods have also been identified. Symmetric behavior of the vertices lead to the study of the metric dimension of A m which gives minimum cardinality of vertices to distinguish all vertices in the graph. We give exact formulae for the metric dimension of A m , when m has exactly two distinct prime divisors. Moreover, we give bounds on the metric dimension of A m , when m has at least three distinct prime divisors.
Likelihood-Based Inference for the Asymmetric Beta-Skew Alpha-Power Distribution
Authors: Martínez-Flórez Guillermo , Tovar-Falón Roger , Jimémez-Narváez Marvin
Published: April 2020

This paper introduces a new family of asymmetric distributions that allows to fit unimodal as well as bimodal and trimodal data sets. The model extends the normal model by introducing two parameters that control the shape and the asymmetry of the distribution. Basic properties of this new distribution are studied in detail. The problem of estimating parameters is addressed by considering the maximum likelihood method and Fisher information matrix is derived. A small Monte Carlo simulation study is conducted to examine the performance of the obtained estimators. Finally, two data set are considered to illustrate the developed methodology.
Analysis of Recurrent Neural Network and Predictions
Authors: Park Jieun , Yi Dokkyun , Ji Sangmin
Published: April 2020

This paper analyzes the operation principle and predicted value of the recurrent-neural-network (RNN) structure, which is the most basic and suitable for the change of time in the structure of a neural network for various types of artificial intelligence (AI). In particular, an RNN in which all connections are symmetric guarantees that it will converge. The operating principle of a RNN is based on linear data combinations and is composed through the synthesis of nonlinear activation functions. Linear combined data are similar to the autoregressive-moving average (ARMA) method of statistical processing. However, distortion due to the nonlinear activation function in RNNs causes the predicted value to be different from the predicted ARMA value. Through this, we know the limit of the predicted value of an RNN and the range of prediction that changes according to the learning data. In addition to mathematical proofs, numerical experiments confirmed our claims.
Limited Microcystin, Anatoxin and Cylindrospermopsin Production by Cyanobacteria from Microbial Mats in Cold Deserts
Authors: Khomutovska Nataliia , Sandzewicz Małgorzata , Łach Łukasz , Suska-Malawska Małgorzata , Chmielewska Monika , Mazur-Marzec Hanna , Cegłowska Marta , Niyatbekov Toirbek , Wood Susanna A. , Puddick Jonathan , Kwiatowski Jan , Jasser Iwona
Published: April 2020

Toxic metabolites are produced by many cyanobacterial species. There are limited data on toxigenic benthic, mat-forming cyanobacteria, and information on toxic cyanobacteria from Central Asia is even more scarce. In the present study, we examined cyanobacterial diversity and community structure, the presence of genes involved in toxin production and the occurrence of cyanotoxins in cyanobacterial mats from small water bodies in a cold high-mountain desert of Eastern Pamir. Diversity was explored using amplicon-based sequencing targeting the V3-V4 region of the 16S rRNA gene, toxin potential using PCR-based methods (mcy, nda, ana, sxt), and toxins by enzyme-linked immunosorbent assays (ELISAs) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Molecular identification of cyanobacteria showed a high similarity of abundant taxa to Nostoc PCC-73102, Nostoc PCC-7524, Nodularia PCC-935 and Leptolyngbya CYN68. The PCRs revealed the presence of mcyE and/or ndaF genes in 11 samples and mcyD in six. The partial sequences of the mcyE gene showed high sequence similarity to Nostoc, Planktothrix and uncultured cyanobacteria. LC-MS/MS analysis identified six microcystin congeners in two samples and unknown peptides in one. These results suggest that, in this extreme environment, cyanobacteria do not commonly produce microcystins, anatoxins and cylindrospermopsins, despite the high diversity and widespread occurrence of potentially toxic taxa.
Phylogenomic Analysis of Secondary Metabolism in the Toxic Cyanobacterial Genera Anabaena, Dolichospermum and Aphanizomenon
Authors: Österholm Julia , Popin Rafael V. , Fewer David P. , Sivonen Kaarina
Published: April 2020

Cyanobacteria produce an array of toxins that pose serious health risks to humans and animals. The closely related diazotrophic genera, Anabaena, Dolichospermum and Aphanizomenon, frequently form poisonous blooms in lakes and brackish waters around the world. These genera form a complex now termed the Anabaena, Dolichospermum and Aphanizomenon (ADA) clade and produce a greater array of toxins than any other cyanobacteria group. However, taxonomic confusion masks the distribution of toxin biosynthetic pathways in cyanobacteria. Here we obtained 11 new draft genomes to improve the understanding of toxin production in these genera. Comparison of secondary metabolite pathways in all available 31 genomes for these three genera suggests that the ability to produce microcystin, anatoxin-a, and saxitoxin is associated with specific subgroups. Each toxin gene cluster was concentrated or even limited to a certain subgroup within the ADA clade. Our results indicate that members of the ADA clade encode a variety of secondary metabolites following the phylogenetic clustering of constituent species. The newly sequenced members of the ADA clade show that phylogenetic separation of planktonic Dolichospermum and benthic Anabaena is not complete. This underscores the importance of taxonomic revision of Anabaena, Dolichospermum and Aphanizomenon genera to reflect current phylogenomic understanding.
Ochratoxin A in Beers Marketed in Portugal: Occurrence and Human Risk Assessment
Authors: Silva Liliana J. G. , Teixeira Ana C. , Pereira André M. P. T. , Pena Angelina , Lino Celeste M.
Published: April 2020

Ochratoxin A (OTA) is produced by fungi present in several agricultural products with much relevance to food safety. Since this mycotoxin is widely found in cereals, beer has a potential contamination risk. Therefore, it was deemed essential to quantify, for the first time, the levels of OTA in beer, a cereal-based product that is marketed in Portugal, as well as to calculate the human estimated weekly intake (EWI) and risk assessment. A total of 85 samples were analyzed through immunoaffinity clean-up, followed by liquid chromatography-fluorescence detection (LC-FD). This analytical methodology allowed a limit of quantification (LOQ) of 0.43 µg/L. The results showed that 10.6% were contaminated at levels ranging between <LOQ and 11.25 µg/L, with an average of 3.14 ± 4.09 µg/L. Samples of industrial production presented lower incidence and contamination levels than homemade and craft beers. On what concerns human risk, the calculated EWI was significantly lower than the tolerable weekly intake (TWI). However, in the worst case scenario, based on a high concentration, the rate EWI/TWI was 138.01%.
Revisiting the 2PN Pericenter Precession in View of Possible Future Measurements
Authors: Iorio Lorenzo
Published: April 2020

At the second post-Newtonian (2PN) order, the secular pericenter precession ω ˙ 2 PN of either a full two-body system made of well-detached non-rotating monopole masses of comparable size and a restricted two-body system composed of a point particle orbiting a fixed central mass have been analytically computed so far with a variety of approaches. We offer our contribution by analytically computing ω ˙ 2 PN in a perturbative way with the method of variation of elliptical elements by explicitly calculating both the direct contribution due to the 2PN acceleration A 2 PN , and also an indirect part arising from the self-interaction of the 1PN acceleration A 1 PN in the orbital average accounting for the instantaneous shifts induced by A 1 PN itself. Explicit formulas are straightforwardly obtained for both the point particle and full two-body cases without recurring to simplifying assumptions on the eccentricity e. Two different numerical integrations of the equations of motion confirm our analytical results for both the direct and indirect precessions. The values of the resulting effects for Mercury and some binary pulsars are confronted with the present-day level of experimental accuracies in measuring/constraining their pericenter precessions. The supermassive binary black hole in the BL Lac object OJ 287 is considered as well. A comparison with some of the results appeared in the literature is made.
Monitoring and Ecotoxicity Assessment of Emerging Contaminants in Wastewater Discharge in the City of Prague (Czech Republic)
Authors: Diaz-Sosa Veronica R. , Tapia-Salazar Mireya , Wanner Jiri , Cardenas-Chavez Diana L.
Published: April 2020

Emerging contaminants (ECs) are not monitored nor regulated consistently, but may have negative effects on human health and ecosystem balance. Although pharmaceuticals and personal care products are among the main ECs found in surface and wastewater, their toxicity and fate are currently not sufficiently studied. In this study, we analyzed for the first time a group of 46 ECs in the secondary effluent of the wastewater treatment plants (WWTP) of Prague. Thirty-seven compounds were identified in the discharge to surface water. Three compounds had no toxicology information on Artemia salina: furosemide, hydrochlorothiazide, and tramadol. We performed acute toxicity (LC50) tests and enzyme assays after 24 and 48 h at room temperature and 28 °C for these three compounds. LC50 ranged from 225.01 mg/L for furosemide, the most toxic, up to above 14,000 mg/L for tramadol. Changes in enzymatic activity for GST, GPx, AChE, and LDH when A. salina were exposed to LC25 for each contaminant were conspicuous and significant in a contaminant-, exposure time-, and temperature-dependent manner. These biochemical markers complement the toxicity profile of these contaminants in aquatic ecosystems and highlight the need for further research on other ECs and their implications, and the regulations required to protect human and ecological health.
Identifying Flow Pathways for Phosphorus Transport Using Observed Event Forensics and the CRAFT (Catchment Runoff Attenuation Flux Tool)
Authors: Adams Russell , Quinn Paul , Barber Nick , Burke Sean
Published: April 2020

Identifying key flow pathways is critical in order to understand the transport of Phosphorus (P) from agricultural headwater catchments. High frequency/resolution datasets from two such catchments in Northwest England enabled individual events to be examined to identify the flow (Q) and Total P (TP) and Total Reactive P (TRP) dynamics (forensics). Detailed analysis of multiple flow and water quality parameters is referred to here as the event forensics. Are there more flow pathways than just surface runoff (dominated by overland flow) and baseflow (mainly groundwater) contributing at the outlet of these catchments? If so, hydrograph separation alone will not be sufficient. This forensic analysis gives a classification of four storm event response types. Three classes are based on the balance of old and new water giving enrichment and dilution of TRP pattern in the subsurface flow. A fourth type was observed where a plume of nutrient is lost to the channel when there is no observed flow. Modelling is also essential when used in combination with the event forensics as this additional tool can identify distinct flow pathways in a robust form. A case study will apply the Catchment Runoff Attenuation Flux Tool (CRAFT) to two contrasting small headwater catchments in Northwest England, which formed part of the Demonstration Test Catchments (DTC) Programme. The model will use data collected during a series of events observed in the two catchments between the period 2012 and 2014. It has the ability to simulate fast near surface (that can represent flow in the upper soil horizons and field drains) and event subsurface soil flow, plus slower groundwater discharge. The model can capture P enrichment, dilution and the role that displacement of “old” P rich water has during events by mixing these flows. CRAFT captures the dominant flow and P fluxes as seen in the forensic analysis and can create outputs including smart export coefficients (based on flow pathways) that can be conveyed to policy makers to better underpin decision making.
Impact of Cruise Activity on Freshwater Use in the Port of Palma (Mallorca, Spain)
Authors: Garcia Celso , Mestre-Runge Christian , Morán-Tejeda Enrique , Lorenzo-Lacruz Jorge , Tirado Dolores
Published: April 2020

Lack of knowledge about freshwater use in ports of tourist destinations hinders accurate assessment of water availability and water planning. In this study, freshwater use in the Port of Palma (Spain) is analyzed by sector (commercial, mixed, navy and recreational) for the period 2007–2018. This study shows the dynamics of consumption and evaluates the effects of increased cruise tourism from 2007 to 2018 in the port. Water data supplied by the Port Authority of the Balearic Islands for each sector, together with water volumes recharged by ships, allow a detailed analysis of the water used by merchants and cruise lines. Results reveal a significant increase in freshwater withdrawals by cruise ships in the Port of Palma in the last ten years, closely related to the boom of cruise activity. Water use and recharge by cruise ships increased in both the high and low tourist seasons. Homeport cruises have a significant effect on the increase of freshwater withdrawals, as each homeport cruise ship recharged a mean volume of 628 m3 per mooring. This paper proposes a water withdrawal indicator of liters loaded per passenger at the port. Given the current lack of restriction on the number of cruise ships per day docking in the Port of Palma, cruise activity may well become a threat to water availability during drought episodes and another environmental cost to add to the already questioned cruise tourism activity of the island.
Risk Assessment of Agricultural Drought Disaster on the Huaibei Plain of China Based on the Improved Connection Number and Entropy Information Diffusion Method
Authors: Chen Menglu , Ning Shaowei , Jin Juliang , Cui Yi , Wu Chengguo , Zhou Yuliang
Published: April 2020

In recent years, drought disaster has occurred frequently in China, causing significant agricultural losses. It is increasingly important to assess the risk of agricultural drought disaster (ADD) and to develop a targeted risk management approach. In this study, an ADD risk assessment model was established. First, an improved fuzzy analytic hierarchy process based on an accelerated genetic algorithm (AGA-FAHP) was used to build an evaluation indicator system. Then, based on the indicators, the ADD assessment connection numbers were established using the improved connection number method. Finally, the entropy information diffusion method was used to form an ADD risk assessment model. The model was applied to the Huaibei Plain in Anhui Province (China), with the assessment showing that, in the period from 2008 to 2017, the plain was threatened continuously by ADD, especially during 2011–2013. The risk assessment showed that southern cities of the study area were nearly twice as likely to be struck by ADD as northern cities. Meanwhile, the eastern region had a higher frequency of severe and above-grade ADD events (once every 21 years) than the western region (once every 25.3 years). Therefore, Huainan was identified as a high-risk city and Huaibei as a low-risk city, with Suzhou and Bengbu more vulnerable to ADD than Fuyang and Bozhou. Understanding the spatial dynamics of risk in the study area can improve agricultural system resilience by optimizing planting structures and by enhancing irrigation water efficiency. This model could be used to provide support for increasing agricultural drought disaster resilience and risk management efficiency.
Dam Breach Size Comparison for Flood Simulations. A HEC-RAS Based, GIS Approach for Drăcșani Lake, Sitna River, Romania
Authors: Albu Liviu-Marian , Enea Andrei , Iosub Marina , Breabăn Iuliana-Gabriela
Published: April 2020

Floods are the most destructive natural phenomenon, by the total number of casualties, and value of property damage, compared to any other type of natural disaster. However, some of the most destructive flash floods are related to dam breaches or complete collapses, that release the large amounts of water, affecting inhabited areas. Worldwide, numerous dams have almost reached or surpassed the estimated construction life span, and pose an increasing risk to structure stability. Considering their continuous degrading state, increasing rainfall aggressiveness, due to climatic changes, technical error, or even human error, there are numerous, potential causes, for which dams could develop breaches and completely fail. This study aims to portray a comparative perspective of flood impact, with real-life consequences, measured by quantifiable parameters, generated from computer simulations of different breach sizes. These parameters include the total flooded surface, water velocity, maximum water depth, number of affected buildings, etc. The analysis was undergone by means of HEC-RAS based 2D hydraulic modeling and GIS, depending on high-accuracy Lidar terrain data and historical hydrological data. As a case study, Drăcșani Lake with the associated Sulița earthfill embankment dam was chosen, being one of the largest and oldest artificial lakes in Romania.
Water Uptake Patterns of Alfalfa under Winter Irrigation in Cold and Arid Grassland
Authors: Wu Jiabin , Li Heping , Niu Jianming , Liu Tiejun , Zheng Hexiang , Xu Xiangtian , Miao Shu
Published: April 2020

Crop reduction caused by cryogenesis and drought is a serious and global problem. The environmental stress caused by low temperature and drought during the overwintering stage of forage is the key factor leading to this low yield. In cold and arid grassland, winter irrigation can effectively alleviate the stress of alfalfa during overwintering, improve the survival rate of alfalfa, and significantly increase the yield. However, the water uptake patterns of alfalfa under winter irrigation are not clear, which are important to explore the mechanism of alleviating environmental stress by winter irrigation. In this research, the stable isotope compositions of all probable water sources and alfalfa xylem water were measured after winter irrigation. A graphical method was applied to identify the main soil layers with water uptake by the alfalfa roots. The contribution rate of available water sources to alfalfa xylem water was quantified by the MixSIAR (Bayesian isotope analysis mixing model in R) model. The results indicated that alfalfa absorbed soil water when the soil water content was high enough in the root layer when under high water volume freezing irrigation (irrigation in early winter when soil is freezing) but not under low and medium water volume freezing irrigation. Alfalfa gradually began to absorb soil water on the third day after thawing irrigation (irrigation in late winter when the soil is thawing) and showed different water uptake characteristics under low, medium, and high water volume. Thawing irrigation also accelerated the regeneration of alfalfa.
Insights into the Photocatalytic Bacterial Inactivation by Flower-Like Bi2WO6 under Solar or Visible Light, Through in Situ Monitoring and Determination of Reactive Oxygen Species (ROS)
Authors: Karbasi Minoo , Karimzadeh Fathallah , Raeissi Keyvan , Rtimi Sami , Kiwi John , Giannakis Stefanos , Pulgarin Cesar
Published: April 2020

This study addresses the visible light-induced bacterial inactivation kinetics over a Bi2WO6 synthesized catalyst. The systematic investigation was undertaken with Bi2WO6 prepared by the complexation of Bi with acetic acid (carboxylate) leading to a flower-like morphology. The characterization of the as-prepared Bi2WO6 was carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), specific surface area (SSA), and photoluminescence (PL). Under low intensity solar light (<48 mW/cm2), complete bacterial inactivation was achieved within two hours in the presence of the flower-like Bi2WO6, while under visible light, the synthesized catalyst performed better than commercial TiO2. The in situ interfacial charge transfer and local pH changes between Bi2WO6 and bacteria were monitored during the bacterial inactivation. Furthermore, the reactive oxygen species (ROS) were identified during Escherichia coli inactivation mediated by appropriate scavengers. The ROS tests alongside the morphological characteristics allowed the proposition of the mechanism for bacterial inactivation. Finally, recycling of the catalyst confirmed the stable nature of the catalyst presented in this study.
Drought Trends and the Extreme Drought Frequency and Characteristics under Climate Change Based on SPI and HI in the Upper and Middle Reaches of the Huai River Basin, China
Authors: Lin Hui , Wang Jingcai , Li Fan , Xie Yangyang , Jiang Chenjuan , Sun Lipin
Published: April 2020

The Huai River Basin (HRB) is an important grain and industrial production area in eastern China with frequent droughts. Under the background of current climate change, the hydrological and meteorological characteristics of the basin may be changed, which may lead to the changes of regional drought characteristics. It should be paid more attention on the drought research under climate change and the difference between different drought indices. Coupled Model Intercomparison Project phase 5 (CMIP5) as an important tool for climate change research has been used in the study and the study chosen three global circulation models (GCMs)—such as CNRM-CM5 (CNR), HadGEM2-ES (Had), and MIROC5 (MIR)—to gather an ensemble model (EnM) for providing the future climate information. The Standardized Precipitation Index (SPI) and Humidity Index (HI) were used to evaluate and compare the drought situations in the past and the future periods with two representative concentration path scenarios (RCP4.5 & RCP8.5). Some sequence statistics methods, such as Mann–Kendall test and run theory, were carried out to analyze the trend and the changes of extreme drought frequency and characteristics values. The research showed that the simulation accuracy of the EnM would better. SPI and HI take different factors into count and thus lead to differences in describing drought trend, extreme drought frequency, and characteristic values, such as drought severity, drought duration, mean drought severity, and max drought intensity. The research showed that both SPI and HI showed the same wetting or drying trend in the same timescales (except winter) as in the historical data. However, the future annual and seasonal drought trend reflected by SPI shows a wetting trend while HI shows a drying trend. Both in the past and the future, extreme drought frequency and characteristic values reflected by HI are higher than SPI. The drought trend is greater, and the extreme drought frequency and characteristics tend to be strengthened under RCP8.5. Low precipitation and high potential evapotranspiration (PET), especially the PET caused by temperature rise, are the main influencing factors of drought in the future. Therefore, the influence of the PET should not be ignored in drought analysis and we should strengthen the comparative study of different drought indices in future drought analysis under climate change.
The Joint Optimal Allocation Study of Regional Total Water Consumption and Pollutant Carrying Capacity of Water Function Areas Based on Emergy Theory
Authors: Guo Xi , Wu Zening , Wang Xinling , Lv Cuimei , Gu Changkuan , Li Yang , Gao Meiyan
Published: April 2020

How to allocate the limited water consumption and pollutant carrying capacity of water function areas to sub-areas and water sectors is key for the practice of the most stringent water resource management decision-making. In response to the joint optimal allocation mechanism of water consumption and pollutant-carrying capacity, joint optimal allocation and the unified quantification problem of multiform benefits, the whole process of joint optimal distribution is refined into the links “water supply—water use and consumption—drainage—pollutant carrying” and the unified quantification method based on the emergy theory to achieve various economic, social, and ecological benefits in different links is proposed. Then the joint optimal allocation joint optimal allocation model of regional water consumption and pollutant carrying capacity is constructed, which realizes the reverse constraint relationship between water quantity and pollution carrying capacity in the water quality and quantity conversion processes. Using Zhengzhou city as an example, the models and methods were applied and researched. Countermeasures and suggestions for the rational allocation of available water resources and water pollution capacity were put forward accordingly.
Assessment of the Dnieper Alluvial Riverbed Stability Affected by Intervention Discharge Downstream of Kaniv Dam
Authors: Obodovskyi Oleksandr , Habel Michał , Szatten Dawid , Rozlach Zakhar , Babiński Zygmunt , Maerker Michael
Published: April 2020

Along the middle reaches of the Dnieper River in central Ukraine, braided riverbeds with many islands have developed in alluvial valleys. In the 1970s, six dams were commissioned, and respective monitoring infrastructure was installed. Riverbanks and valley floors composed of unconsolidated material have much lower bank strengths and are susceptible to fluvial erosion and bank collapse, particularly during the release of high flow volumes from hydropower dams. The regulation of the Dnieper River along a cascade of storage reservoirs caused significant changes in its active river channel and hydrological regime. In order to estimate channel stability downstream of the Kaniv reservoir, we conducted an analysis of the hydraulic conditions in terms of changes in flow velocity and propagation of waves caused by intervention water discharges from the Kaniv Hydroelectric Power Plant (HPP). In this paper, we assess the hydromorphological parameters of the studied river reach as well as the characteristics of the related erosion and deposition zones. Therefore, a monitoring framework for channel processes (MCP) downstream of the Kaniv HPP was installed. The analysis of the intervention discharge parameters was conducted based on measurements from July 2015. Channel stability was expressed by the following factors: Lohtin’s number (L), Makkaveev’s (Kc) factor of stability, and a complex index of stability (Mx) by Grishanin. This study shows that the velocity of artificial wave propagation may reach a speed of up to 74.4 km·h−1. The wave propagates for a distance of approx. 45 km within 65 min at a mean velocity of 37.4 km·h−1. The L, Kc, and Mx indicators used in this work showed that when water discharge increased (e.g., during typical peak-capacity operation), the channel becomes unstable and sediments are subject to erosion processes. The riverbed stability indicators clearly illustrate that an increase in parameter values is not dependent on the distance to the dam. The results are valuable for sustainable sediment management at catchment scale and hence, directly applicable in water management.
Indicadores y sistemas de cuentas ambientales y económicas integrados. Grado de instrumentación: el estado actual
Authors: Cano Orellana Antonio , Rodríguez Morilla Carmen
Published: April 2020

Los sistemas de cuentas nacionales e indicadores estándares no miden adecuadamente la calidad ambiental y el bienestar de la población. A finales de los años ochenta del pasado siglo se iniciaron reformas e iniciativas destinadas a su mejora: extensión del marco central del Sistema de Cuentas Nacionales (Naciones Unidas 1993), integración de la economía y el medio ambiente a través de un sistema de cuentas conocido como el Sistema de Contabilidad Ambiental y Económica Integrada (SCAEI) (Naciones Unidas-2003) y generación de indicadores estructurales. Cómo han evolucionado sendos aspectos y la relación entre ellos, cuál es el alcance de los cambios realizados y su aplicación en los países, es el propósito de este artículo.
Evaluación del sistema de gestión: el caso del programa Opciones Productivas en su vertiente de cofinanciamiento en la región III de Yucatán, México
Authors: Leyva Morales Carlos , Moo Novelo Carlos , Magaña Magaña Miguel
Published: April 2020

Se evaluó la gestión y el impacto de los proyectos productivos financiados a través del programa Opciones productivas en su vertiente de cofinanciamiento en la región III de Yucatán con énfasis en la generación de empleos y mejora de las condiciones generales de bienestar de las familias. Se encontró que el programa ha tenido un éxito parcial en esta región de la entidad en la generación de empleos. Que la permanencia de los proyectos contribuyó con el 80% del autoempleo generado entre los integrantes de los grupos apoyados. Que el programa solo está mejorando el nivel de ingreso de unos pocos de los beneficiarios del mismo en los municipios de esta región y en general no está contribuyendo a mejorar la calidad de vida, esto último ha sido resultado de otros apoyos otorgados por el gobierno federal o estatal. Y que la problemática que existe en su gestión se circunscribe a: excesiva demanda de solicitudes de apoyo en la Secretaria de Política Comunitaria y Social, asignación de recursos no siempre objetiva, retraso en la respuesta a los beneficiarios, el seguimiento de proyectos no es adecuado y existen conflictos de coordinación que no permiten la firma de acuerdos de colaboración entre la Secretaria de Desarrollo Social y la Secretaria de Política Comunitaria y Social.
Articulación estructural en el Distrito Federal
Authors: Jiménez Reyes Alonso , Márquez Mendoza Marco Antonio
Published: April 2020

La articulación estructural se refiere a la forma en que los agentes económicos interactúan en la compra y venta de bienes y servicios. Desde la estructura productiva, las industrias son oferentes y demandantes de insumos y productos, cuyas interrelaciones forman redes, en las que cada industria juega un papel distinto. A partir de las redes económicas es posible identificar el papel articulador de cada industria, es decir, si emite o recibe influencia de los miembros de la red, o si tiene vínculos fuertes con otros, así estas características se refieren a la centralidad que tiene un agente en la estructura. Este trabajo utiliza la estimación de una tabla de insumo producto para la economía del Distrito Federal del 2008 cuyo interés es identificar los llamados Coeficientes Importantes que determinan el nivel de integración y por medio de los cuales se generan grafos dirigidos y a partir de estos resultados se identifica la forma de articulación mediante las medidas de centralidad propuestas por las redes sociales pero medidas desde la teoría de grafos.
Ley de energía para el campo: análisis de incentivos y propuestas de reforma
Authors: Andere Jorge L.
Published: April 2020

Se presenta un análisis económico de la Ley de energía para el campo, (LEC) que examina cómo su diseño afecta los mercados y crea una estructura de información que favorece la extracción de rentas. Mediante modelos sencillos de equilibrio parcial y de agente-principal se muestra que las tarifas de estímulo para bombeo agrícola distorsionan las relaciones de producción en el campo mexicano y que, lejos de favorecer la productividad, incrementan artificialmente la demanda de energía y la sobreexplotación de acuíferos. Se proponen tres opciones de reforma que mejorarían la eficiencia y disminuirían la extracción de rentas.
Rotación de personal en los Call Center de Mérida, Yucatán, México
Authors: Leyva Morales Carlos , Vela Manzanilla Raúl , Brangel Xool Karén
Published: April 2020

Se plantea como objetivo analizar la rotación del personal en los Call Center de Mérida, Yucatán para identificar los factores que determinan en los trabajadores la intención de permanecer en sus puestos laborales. La investigación se desarrolló a través de un diseño transversal descriptivo y para la recolección de datos se aplicó una cédula de entrevista semiestructurada a 120 empleados y una guía de entrevista a los gerentes de operaciones de tres empresas. Los resultados evidencian que en el ramo estudiado los trabajadores devengan un salario alto y justo, mas no satisfactorio; que la gran mayoría de ellos alcanzan los indicadores de productividad de la empresa, la cual está determinada por el salario y el logro de objetivos y que el trabajo en los Call Center es funcional dando lugar a una alta tasa de rotación del personal. Se concluye que el salario, la dirección, los estímulos morales y materiales y la motivación del personal en estas empresas son los factores principales que se relacionan con la rotación de personal observada.