bluuebunny/crossref_metadata_2025 huggingface dataset:
Is Anoxic Operation Effective to Control Nitrate Build-Up and Sludge Loss for the Combined Partial Nitritation and Anammox (CPNA) Process?
Authors: Wang Hongyan , Wang Yuanyue , Zhang Junya , Sui Qianwen , Hu Dazhou , Zuo Fumin , Wei Yuansong
Published: August 2020

There were three main issues of long start-up period, nitrate build-up and sludge loss during the operation of combined partial-nitritation anammox (CPNA). To fully start up the CPNA reactor, the fast achievement of partial-nitritation (PN) was the first step. Firstly, the PN process was successfully achieved within 22 days by 2 mg·L−1 hydroxylamine (NH2OH) addition and online intermittent aeration control at 0.2~0.3 mg·L−1 dissolved oxygen (DO). Then, a novel strategy of adding anoxic stirring phase between feeding and aeration period during CPNA operation was applied. It was shown effective to control nitrate build-up since the mole ratio of NO3−-N production and NH4+-N removed (MNRR) was mostly below 15%. Also, the procedure adjustment was proven useful to alleviate sludge loss by sustaining filamentous bacteria that could act as biomass framework and reduce nitrate substrate. The filamentous denitrifying bacteria could cause sludge bulking. The total nitrogen removal rate (TNRR) varied from 0.20 to 0.45 kg·m−3·d−1 during CPNA operation. In Stage III, after adding anoxic stirring phase, the abundance of nitrogen transformation functional microorganism’s nitrite oxidizing bacteria (NOB) was below 1.6%, which was one order of magnitude lower than Anammox and ammonia oxidizing bacteria (AOB).
A Note on Simulation Pricing of π-Options
Authors: Palmowski Zbigniew , Serafin Tomasz
Published: August 2020

In this work, we adapt a Monte Carlo algorithm introduced by Broadie and Glasserman in 1997 to price a π-option. This method is based on the simulated price tree that comes from discretization and replication of possible trajectories of the underlying asset’s price. As a result, this algorithm produces the lower and the upper bounds that converge to the true price with the increasing depth of the tree. Under specific parametrization, this π-option is related to relative maximum drawdown and can be used in the real market environment to protect a portfolio against volatile and unexpected price drops. We also provide some numerical analysis.
Automated Channel Selection in High-Density sEMG for Improved Force Estimation
Authors: Hajian Gelareh , Etemad Ali , Morin Evelyn
Published: August 2020

Accurate and real-time estimation of force from surface electromyogram (EMG) signals enables a variety of applications. We developed and validated new approaches for selecting subsets of high-density (HD) EMG channels for improved and lower-dimensionality force estimation. First, a large dataset was recorded from a number of participants performing isometric contractions in different postures, while simultaneously recording HD-EMG channels and ground-truth force. The EMG signals were acquired from three linear surface electrode arrays, each with eight monopolar channels, and were placed on the long head and short head of the biceps brachii and brachioradialis. After data collection and pre-processing, fast orthogonal search (FOS) was employed for force estimation. To select a subset of channels, principal component analysis (PCA) in the frequency domain and a novel index called the power-correlation ratio (PCR), which maximizes the spectral power while minimizing similarity to other channels, were used. These approaches were compared to channel selection using time-domain PCA. We selected one, two, and three channels per muscle from the original seven differential channels to reduce the redundancy and correlation in the dataset. In the best case, we achieved an approximate improvement of 30% for force estimation while reducing the dimensionality by 57% for a subset of three channels.
Local Positioning System Analysis of Physical Demands during Official Matches in the Spanish Futsal League
Authors: Serrano Carlos , Felipe Jose Luis , Garcia-Unanue Jorge , Ibañez Enrique , Hernando Enrique , Gallardo Leonor , Sanchez-Sanchez Javier
Published: August 2020

The aim of this study was to analyze the influence of the match half and the playing position on physical requirements in the Spanish Professional Futsal League players during official games. The external load from distance, speed, acceleration and deceleration variables were obtained from fourteen elite futsal players during 10 official matches of the 2019–2020 season using a Local Positioning System with ultra-wideband technology installed on the futsal pitch. The results revealed similar results from physical requirements between first and second half (p > 0.05). Wingers demonstrated greater high-speed running distance (+4.04 m·min−1; CI95%: 0.35 to 7.72; ES: 0.87) than pivots (p > 0.05). There were a high number of accelerations (7.42–9.41 n·min−1) and decelerations (7.37–9.12 n·min−1) per minute in all player positions. The principal finding of the current manuscript did not evidence differences in the physical performance of players between the first and second half. The physical requirements varied among pivots and wingers regarding high-intensity actions. These outcomes add new contributions to the understanding of futsal physical demands.
Development of an Acoustic System for UAV Detection
Authors: Dumitrescu Cătălin , Minea Marius , Costea Ilona Mădălina , Cosmin Chiva Ionut , Semenescu Augustin
Published: August 2020

The purpose of this paper is to investigate the possibility of developing and using an intelligent, flexible, and reliable acoustic system, designed to discover, locate, and transmit the position of unmanned aerial vehicles (UAVs). Such an application is very useful for monitoring sensitive areas and land territories subject to privacy. The software functional components of the proposed detection and location algorithm were developed employing acoustic signal analysis and concurrent neural networks (CoNNs). An analysis of the detection and tracking performance for remotely piloted aircraft systems (RPASs), measured with a dedicated spiral microphone array with MEMS microphones, was also performed. The detection and tracking algorithms were implemented based on spectrograms decomposition and adaptive filters. In this research, spectrograms with Cohen class decomposition, log-Mel spectrograms, harmonic-percussive source separation and raw audio waveforms of the audio sample, collected from the spiral microphone array—as an input to the Concurrent Neural Networks were used, in order to determine and classify the number of detected drones in the perimeter of interest.
Enhancement of PVDF Sensing Characteristics by Retooling the Near-Field Direct-Write Electrospinning System
Authors: Hoe Zheng-Yu , Chang Chun-Chieh , Chen Jia-Jin Jason , Yen Chung-Kun , Wang Shao-Yu , Kao Yu-Hsuan , Li Wei-Ming , Chen Wen-Fan , Pan Cheng-Tang
Published: August 2020

This research aimed to develop a direct-write near-field electrospinning system (DW-NFES) with three-axis positioning of controllable speed, torque and position to produce sizable and high-quality piezoelectric fibers for sensing purposes. Sensor devices with high electrical response signals were developed and tested. To achieve DW-NFES purpose, a servo motor controller was designed to develop a high response rate, accurate positioning, and stable mobile device through the calculation of bandwidth and system time delay. With this retooled system of DW-NFES, controllable and uniform size fibers in terms of diameters, stretching force, and interspaces can be obtained. Sensor devices can be made selectively without a complicated lithography process. The characteristics of this DW-NFES platform were featured by high response rate, accurate positioning, and stable movement to make fibers with high piezoelectric property. In this study, polyvinylidene fluoride (PVDF) was used to explore and enhance their sensing quality through the platform. The parametric study of the process factors on piezoelectric sensing signals mainly included the concentration of electrospinning PVDF solution, high voltage electric field, and collection speed. Finally, the surface morphology and piezoelectric properties of the as-electrospun PVDF fibers were examined by scanning electron microscopy (SEM) and characterized by electrical response measurement techniques. The results showed that the fiber spinning speed of the DW-NFES system could be increased to ~125 from ~20 mm/s and the accuracy precision was improved to ~1 from ~50 μm, compared to conventional step motor system. The fiber diameter reached ~10 μm, and the electrospinning pitch reached to as small as ~10 μm. The piezoelectric output voltage of the electrospun fibers was increased ~28.6% from ~97.2 to ~125 mV; the current was increased ~27.6% from ~163 to ~208 nA, suggesting that the piezoelectric signals can be enhanced significantly by using this retooled system. Finally, an external control module (Arduino-MAGE) was introduced to control the PVDF piezoelectric fiber sensors integrated as a sensing array. The behavior of long-term sedentary patients can be successfully detected by this module system to prevent the patients from the bedsores.
The Rio Olympic Games: A Look into City Dynamics through the Lens of Twitter Data
Authors: Condeço-Melhorado Ana , Mohino Inmaculada , Moya-Gómez Borja , García-Palomares Juan Carlos
Published: August 2020

The Olympic Games have a huge impact on the cities where they are held, both during the actual celebration of the event, and before and after it. This study presents a new approach based on spatial analysis, GIS, and data coming from Location-Based Social Networks to model the spatiotemporal dimension of impacts associated with the Rio 2016 Olympic Games. Geolocalized data from Twitter are used to analyze the activity pattern of users from two different viewpoints. The first monitors the activity of Twitter users during the event—The arrival of visitors, where they came from, and the use which residents and tourists made of different areas of the city. The second assesses the spatiotemporal use of the city by Twitter users before the event, compared to the use during and after the event. The results not only reveal which spaces were the most used while the Games were being held but also changes in the urban dynamics after the Games. Both approaches can be used to assess the impacts of mega-events and to improve the management and allocation of urban resources such as transport and public services infrastructure.
Consumer Preferences for Sustainability in Food and Non-Food Horticulture Production
Authors: Isaak Marike , Lentz Wolfgang
Published: August 2020

Although a large number of studies describe sustainability in horticulture for individual crops or use individual sustainability characteristics as examples, there is still a lack of information on what consumers regard as being the relevant criteria for sustainability in horticultural production in the German market. The aim of this paper is to provide a broad overview of the relevance of different sustainability characteristics for flowers and ornamental plants as well as for fruit and vegetables from a consumer perspective. First, the sustainability characteristics from the literature were grouped according to the four sustainability dimensions of ecology, economy, and social and corporate responsibility. Second, an exploratory online consumer survey was conducted for both non-food horticulture (ornamental plants and nursery products) and food horticulture (open field fruit and vegetables) with the aim of determining the initial significant indicators for various sustainability characteristics for consumers. A confirmatory factor analysis confirmed the four dimensions of the literature research. According to the survey results, the characteristics of ecology were highly relevant to the respondents, followed by the characteristics of social sustainability. However, some characteristics of social sustainability and corporate responsibility could not be confirmed by the model.
Evoking Agriculture Entrepreneurship: How Younger and Older Farmers Differ
Authors: Chen Chao-Chien , Liang Chaoyun
Published: August 2020

This study examined the agriculture entrepreneurial intentions (AEIs) of current farmers (n = 1183) in Taiwan and distinguished differences between ≤45- and >45-year-old farmers by applying the theory of planned behaviour with the extension of personality traits. The results determined that the entrepreneurial commitment and communication aspects of entrepreneurial self-efficacy (ESE) considerably affected the conviction dimension of AEI, whereas entrepreneurial commitment, communication ESE, entrepreneurial attitude, planning ESE, and neuroticism notably influenced the preparation dimension of AEI. Furthermore, the effects of neuroticism on entrepreneurial conviction were weaker in younger farmers than in older farmers, and the effects of entrepreneurial commitment, entrepreneurial attitude, neuroticism, and planning ESE on entrepreneurial preparation in younger farmers were different from those in older farmers. Moreover, length of agricultural engagement exhibited an inverted U-shaped curvilinear relationship with AEIs. The present study contributes to the understanding of how younger farmers’ AEIs can be shaped and how they may cope with the differences they may have compared with older family members.
International Forest Governance and Policy: Institutional Architecture and Pathways of Influence in Global Sustainability
Authors: Sotirov Metodi , Pokorny Benno , Kleinschmit Daniela , Kanowski Peter
Published: August 2020

This paper reviews the design of the international forest governance and policy, and analyses its impacts in addressing deforestation and forest degradation as global sustainability issues. Informed by literatures on international relations, regulatory governance of global commodity production, and international pathways of domestic influence, key arrangements are aggregated into six types, and mapped in terms of their main aims, instruments, and implementation mechanisms. Key analytical dimensions, such as the actors involved (state–private–mixed), the character of legal authority (legally binding–non-legally binding), and the geopolitical scope (global–transnational) helped to identify the potential and limitations of arrangements. They were assessed and compared in terms of their main pathways of influence such as international hard-law rules, cross-sectoral policy integration, non-legally binding norms and discourses, global market mechanisms, and direct access through capacity building. Our results reveal important challenges in the design and implementation, and in the pathways of influence, of the forest governance arrangements, including major inconsistencies with forest-adverse economic sectors. We conclude about the need for coherent international forest-related policy cooperation and integrative actions in agriculture, bioenergy, and mining to enhance the prospects of achieving the UN 2030 Sustainable Development Goals.
Scenarios for the Development of Multimodal Transport in the TRITIA Cross-Border Area
Authors: Kramarz Marzena , Dohn Katarzyna , Przybylska Edyta , Knop Lilla
Published: August 2020

As the demand for transport is growing, more and more attention is being paid to its quality aspects. These include, among other things, efficiency, safety, and a continuous effort to reduce external costs. That is why the transport policies of the EU countries and individual regions are increasingly addressing the issue of sustainable transport development. Multimodal transport, which is seen as a key element to effectively counterbalance the dominant role of vehicle transport in the economic progress of the European Community, plays an important role in these programmes. For consistency and continuity of freight flows, cooperation between neighbouring countries and regions is essential. The future of multimodal freight transport within the cross-border area of Poland, Czech Republic and Slovakia is not as evident as the transport policies imply. Therefore, the purpose of the paper is to identify a set of factors determining the development of multimodal transport within the cross-border area of TRITIA (The European Grouping of Territorial Cooperation of the four regional governments of Moravian-Silesian Region (CZ), Opole Voivodeship (PL), Silesian Voivodeship (PL) and Žilina Self-governing Region (SK)) and to develop four scenarios, the execution of which in the 2030 perspective depends on the implementation of cross-border infrastructure and organisational projects and the increasing level of cooperation in the field of multimodal transport. The article contains the methodology for developing scenarios of multimodal freight transport development. The research showed that initiating activities targeted at the development of multimodal transport within the cross-border area requires the involvement of all participants in the process, i.e., all countries (Poland, Czech Republic and Slovakia), along with many different stakeholders. The future development of multimodal transport as provided for in the scenarios is not linearly correlated with the increase in cooperation and the number of implemented infrastructure and organisational projects. It is vital for future research to define the role of stakeholders both in terms of cooperation and collaboration development.
Transferring COVID-19 Challenges into Learning Potentials: Online Workshops in Architectural Education
Authors: Milovanović Aleksandra , Kostić Miloš , Zorić Ana , Đorđević Aleksandra , Pešić Mladen , Bugarski Jovana , Todorović Dejan , Sokolović Neda , Josifovski Andrej
Published: August 2020

The paper addresses the shift in architectural education regarding the need to develop new approaches in teaching methodology, improve curricula, and make advancements in new learning arenas and digital environments. The research is based on the assumption that online workshops could offer a unique learning experience for students in higher education. Accordingly, workshops are considered an essential element in teaching emergency design. As a result, this can produce broader and more innovative solutions to COVID-19 challenges regarding social distancing, limited movements, regulated use of public space, and suspended daily activities. The theoretical notions of emergency design and education for sustainable design enabled the identification of research perspectives and spatial levels to be taken as a starting point of the workshop “COVID-19 Challenges: Architecture of Pandemic” that was conducted by the University of Belgrade—Faculty of Architecture in April 2020. The critical review of the workshop’s procedural and substantial aspects led to identifying four main COVID-19 design challenges perceived in performance, innovation, alteration, and inclusion. Additionally, the paper’s findings concern the identification of learning potentials and limitations arising from a current topic affecting global society, for which neither solutions nor adequate answers in the field of architecture and urbanism have been found.
Erratum: Ly, H.-B., et al. Computational Hybrid Machine Learning Based Prediction of Shear Capacity for Steel Fiber Reinforced Concrete Beams. Sustainability 2020, 12, 2709
Authors: Ly Hai-Bang , Le Tien-Thinh , Vu Huong-Lan Thi , Tran Van Quan , Le Lu Minh , Pham Binh Thai
Published: August 2020

The authors would like to make the following corrections to the published paper [...]
A Refinement of the Conjecture on the Pseudo Component Transformation of the Lattice Points in the Simplex
Authors: Kim Bara , Kim Jeongsim
Published: August 2020

We consider mixture experiments in which the proportions of the components must be non-negative and their sum must equal one. Thus, the experimental region for a mixture of components is a simplex. Li and Zhang (2017) made the conjecture that the pseudo component transformation of the lattice points in the simplex has a special property. In this paper, we show that this conjecture is not true in general. Furthermore, we refine this conjecture and prove the refined conjecture.
Time Series Effect on Surface Deformation above Goaf Area with Multiple-Seam Mining
Authors: Shi Zhenyue , Wang Qingbiao , Wang Pu , He Donglin , Bai Yun , You Hongyue
Published: August 2020

The surface subsidence caused by coal mining is a large area, and computer simulation is a fast and intuitive method, which can help us understand the macroscopic subsidence law. The mined-out area left over by coal mining is not disposed of appropriately for a long time. Thus, it can easily cause ground subsidence, collapse, or spot cracking, especially when mining multiple coal seams, which seriously restricts the construction and safety of the near-surface rock and soil layers. Based on the engineering background of five-layer coal mining in the Beibu Coal Mine of Laiwu City, a “Fast Lagrangian Analysis of Continua in 3D” numerical calculation model was established. The model was used to analyze the surface deformation indexes of four groups with different mining sequences in multiple coal seams, revealing the sequence effects of mining time on the surface deformation law in the goaf collapse areas, hence obtaining optimal mining sequences. The results showed that the four groups of mining sequences (including vertical settlement and horizontal deformation) have stable surface deformation centers, but the deformation ranges and amounts are quite different. The settlement deformation is the main difference. Mining sequence I has the largest deformation of 62.7 cm, followed by mining sequence III. Mining sequences II and IV are basically the same, at only 22% of the value of mining sequence 1. A multi-index analysis of the surface deformation curve including the inflection point, stagnation point, and slope showed that the larger the surface deformation, the more evident the change of the curve (concave or convex) and slope, the more uneven the foundation stress, the more severe the damage to the surface structures, and the less suitable the surface construction. Finally, upon analyzing the indicators of surface stability and adaptability, mining sequence IV was indicated as the optimal scheme. It is suggested that an optimal mining sequence should be appropriately selected before the mining of multiple coal seams. The research results can provide effective guidance for addressing surface deformations under similar geological conditions, and can provide scientific evaluations for the safety and stability of surface buildings and structures, leading to considerable economic and social benefits.
Balancing User Comfort and Energy Efficiency in Public Buildings through Social Interaction by ICT Systems
Authors: Franco Alessandro
Published: August 2020

Energy efficiency, indoor environmental quality, and comfort in public buildings has received increasing attention in recent years as it can contribute to maintaining safety conditions and to the reduction of conventional fuels consumption, energy costs for building owners, and greenhouse gas emissions. People are an integral part of any building energetic ecosystem as, according to some estimates, they spend a great part of their life in indoor spaces. On one side, occupants are responsible for the energy consumption of the building and for this reason the “psychology of energy saving” has received attention since the 70s up to recent results. On the other hand, strategies for energy efficiency should not jeopardize occupants’ health and quality of life. While general awareness of the value of environmental variables has increased in the last few years, this interest has recently been further exacerbated by the spreading of the well-known COVID-19 pandemic. In fact, as most countries have started planning post-lock-down activities, there is a growing concern regarding how social distancing measures can be enforced in shared buildings and strict indoor air quality control can prevent airborne virus transmission in crowded spaces. The paper discusses the perspectives of increasing the level of social interaction of building users through the systematic use of Information and Communication Technologies (ICT), and in particular, some specific platforms. The ICT system, taking information from the occupants in a concerted way, can be an important instrument to collect data, coming both from physical sensors and from people to develop a multi-objective control strategy for the Heating, Ventilation, and Air Cooling (HVAC) systems in order to obtain energy savings whilst balancing user comfort and healthy conditions.
Demographic Performance of Helicoverpa zea Populations on Dual and Triple-Gene Bt Cotton
Authors: Rabelo Marcelo M. , Paula-Moraes Silvana V. , Pereira Eliseu Jose G. , Siegfried Blair D.
Published: August 2020

Insecticidal toxins from Bacillus thuringiensis (Bt) are valuable tools for pest management worldwide, contributing to the management of human disease insect vectors and phytophagous insect pests of agriculture and forestry. Here, we report the effects of dual and triple Bt toxins expressed in transgenic cotton cultivars on the fitness and demographic performance of Helicoverpa zea (Boddie)—a noctuid pest, known as cotton bollworm and corn earworm. Life-history traits were determined for individuals of three field populations from a region where H. zea overwintering is likely. Triple-gene Bt cotton cultivars that express Cry and Vip3Aa toxins killed 100% of the larvae in all populations tested. In contrast, dual-gene Bt cotton that express Cry1Ac+Cry1F and Cry1Ac+Cry2Ab allowed population growth with the intrinsic rate of population growth (rm) 38% lower than on non-Bt cotton. The insects feeding on Bt cotton plants that express Cry1Ac+Cry2Ab, Cry1Ac+Cry1F, or Cry1Ab+Cry2Ae exhibited reduced larval weight, survival rate, and increased development time. Additionally, fitness parameters varied significantly among the insect populations, even on non-Bt cotton plants, likely because of their different genetic background and/or previous Bt toxin exposure. This is the first report of the comparative fitness of H. zea field populations on dual-gene Bt cotton after the recent reports of field resistance to certain Bt toxins. These results document the population growth rates of H. zea from an agricultural landscape with 100% Bt cotton cultivars. Our results will contribute to the development and validation of resistance management recommendations.
The Role of Microglia during West Nile Virus Infection of the Central Nervous System
Authors: Stonedahl Sarah , Clarke Penny , Tyler Kenneth L.
Published: August 2020

Encephalitis resulting from viral infections is a major cause of hospitalization and death worldwide. West Nile Virus (WNV) is a substantial health concern as it is one of the leading causes of viral encephalitis in the United States today. WNV infiltrates the central nervous system (CNS), where it directly infects neurons and induces neuronal cell death, in part, via activation of caspase 3-mediated apoptosis. WNV infection also induces neuroinflammation characterized by activation of innate immune cells, including microglia and astrocytes, production of inflammatory cytokines, breakdown of the blood-brain barrier, and infiltration of peripheral leukocytes. Microglia are the resident immune cells of the brain and monitor the CNS for signs of injury or pathogens. Following infection with WNV, microglia exhibit a change in morphology consistent with activation and are associated with increased expression of proinflammatory cytokines. Recent research has focused on deciphering the role of microglia during WNV encephalitis. Microglia play a protective role during infections by limiting viral growth and reducing mortality in mice. However, it also appears that activated microglia are triggered by T cells to mediate synaptic elimination at late times during infection, which may contribute to long-term neurological deficits following a neuroinvasive WNV infection. This review will discuss the important role of microglia in the pathogenesis of a neuroinvasive WNV infection. Knowledge of the precise role of microglia during a WNV infection may lead to a greater ability to treat and manage WNV encephalitis.
Clustering of Time Series Water Quality Data Using Dynamic Time Warping: A Case Study from the Bukhan River Water Quality Monitoring Network
Authors: Lee Seulbi , Kim Jaehoon , Hwang Jongyeon , Lee EunJi , Lee Kyoung-Jin , Oh Jeongkyu , Park Jungsu , Heo Tae-Young
Published: August 2020

It is essential to monitor water quality for river water management because river water is used for various purposes and is directly related to the health and safety of a population. Proper network installation and removal is an important part of water quality monitoring and network operation efficiency. To do this, cluster analysis based on calculated similarity between measuring stations can be used. In this study, we measured the similarities between 12 water quality monitoring stations of the Bukhan River. River water quality data always have a station-dependent time lag because water flows from upstream to downstream; therefore, we proposed a Dynamic Time Warping (DTW) algorithm that searches for the minimum distance by changing and comparing time-points, rather than using the Euclidean algorithm, which compares the same time-point. Both Euclidean and DTW algorithms were applied to nine water quality variables to identify similarities between stations, and K-medoids cluster analysis were performed based on the similarity. The Clustering Validation Index (CVI) was used to select the optimal number of clusters. Our results show that the Euclidean algorithm formed clusters by mixing mainstream and tributary stations; the mainstream stations were largely divided into three different clusters. In contrast, the DTW algorithm formed clear clusters by reflecting the characteristics of water quality and watershed. Furthermore, because the Euclidean algorithm requires the lengths of the time series to be the same, data loss was inevitable. As a result, even where clusters were the same as those obtained by DTW, the characteristics of the water quality variables in the cluster differed. The DTW analysis in this study provides useful information for understanding the similarity or difference in water parameter values between different locations. Thus, the number and location of required monitoring stations can be adjusted to improve the efficiency of field monitoring network management.
Isotope Composition of Precipitation, Groundwater, and Surface and Lake Waters from the Plitvice Lakes, Croatia
Authors: Krajcar Bronić Ines , Barešić Jadranka , Sironić Andreja , Lovrenčić Mikelić Ivanka , Borković Damir , Horvatinčić Nada , Kovač Zoran
Published: August 2020

The application of tritium, 2H, and 18O in the characterization of the precipitation, groundwater, and surface and lake water of the Plitvice Lakes (PL), Croatia, over the 1979–2019 period is presented. An increase in the mean annual air temperature of 0.06 °C/year and in the annual precipitation amount of 10 mm/year is observed. The good correlation of the tritium activity concentration in the PL and Zagreb precipitation implies that the tritium data for Zagreb are applicable for the study of the PL area. The best local meteoric water line at PL was obtained by the reduced major axis regression (RMA) and precipitation-weighted ordinary least squares regression (PWLSR) approaches: δ2HPWLSR = (7.97 ± 0.12) δ18O + (13.8 ± 1.3). The higher deuterium excess at PL (14.0 ± 2.2 ‰) than that at Zagreb reflects the higher altitude and influence of the Mediterranean precipitation. The δ2H in precipitation ranges from −132.4‰ to −22.3‰ and δ18O from −18.3 ‰ to −4.1‰. The much narrower ranges in the groundwater (<1‰ in δ18O, <10‰ in δ2H) indicate the good mixing of waters in aquifers and short mean residence times. The higher average δ2H in all three karst springs observed after 2003 can be attributed to the increase in the mean air temperature. The mean δ2H and δ18O values in the surface and lake water increase downstream due to the evaporation of surface waters. There is no significant difference between the surface water line and the lake water line (2011–2014). The stable isotope composition of the surface and lake waters reacts to extreme hydrological conditions.
Solving Inverse Problems of Unknown Contaminant Source in Groundwater-River Integrated Systems Using a Surrogate Transport Model Based Optimization
Authors: Jamshidi Azade , Samani Jamal Mohammad Vali , Samani Hossein Mohammad Vali , Zanini Andrea , Tanda Maria Giovanna , Mazaheri Mehdi
Published: August 2020

The paper presents a new approach to identify the unknown characteristics (release history and location) of contaminant sources in groundwater, starting from a few concentration observations at monitoring points. An inverse method that combines the forward model and an optimization algorithm is presented. To speed up the computation, the transfer function theory is applied to create a surrogate transport forward model. The performance of the developed approach is evaluated on two case studies (literature and a new one) under different scenarios and measurement error conditions. The literature case study regards a heterogeneous confined aquifer, while the proposed case study was never investigated before, it involves an aquifer-river integrated flow and transport system. In this case, the groundwater contaminant originated from a damaged tank, migrates to a river through the aquifer. The approach, starting from few concentration observations monitored at a downstream river cross-section, accurately estimates the release history at a groundwater contaminant source, even in presence of noise on observations. Moreover, the results show that the methodology is very fast, and can solve the inverse problem in much less computation time in comparison with other existing approaches.
Internal Erosion Failure of Uniform Sands under Confinement and Constricted Seepage Exit
Authors: Chang Kuang-Tsung , Lee Kevin Zeh-Zon , Wu Han-Yu
Published: August 2020

Seepage water may move soil particles and cause internal erosion of soils, leading to sinkholes and the collapse of embankments and slopes. To account for the effects of confinement and constricted seepage exit, a test apparatus was developed to study the internal erosion of granular soils under various confining pressures, particle sizes, and sizes of the seepage exit opening. As indicated in the literature, the behavior of internal erosion has been largely studied by laboratory experiments and field investigations, and mechanical models that help describe the failure mechanism of internal erosion are less prevalent. A hydro-mechanical model that incorporates the fluid drag force and the shear strength of soil was therefore developed for quantifying the internal erosion experiments conducted in this study. The experimental results showed that the greater the confining pressure or the particle size, the greater the critical velocity; the greater the seepage exit opening, the smaller the critical velocity. The critical velocity predicted by the proposed hydro-mechanic model compares reasonably well with the experimental data. In addition to the confining pressure, particle size, and size of the seepage exit opening, the proposed model also showed that the friction angle and porosity of the soil are factors influencing the critical velocity, which is consistent with the experimental findings of this study.
Simulation of a Hydrostatic Pressure Machine with Caffa3d Solver: Numerical Model Characterization and Evaluation
Authors: Pienika Rodolfo , Usera Gabriel , Ramos Helena
Published: August 2020

The Hydrostatic Pressure Machine (HPM) is a novel energy converter for micro and pico hydropower that becomes very suitable for installation in channels with very low head, where conventional hydraulic turbines are inadequate or too expensive. Although this technology has been studied through several experimental tests and also by numerical simulations, open source flow solvers have not been used yet. The research team on Computational Fluid Mechanics of IMFIA- Universidad de la República (Uruguay) has been developing a CFD open source solver named caffa3d, which has obtained great results in a few international challenges, although it has not been used yet for free surface flows or turbomachinery simulations. The present work shows the contributions made within caffa3d in order to enable its use for simulating a HPM. The Large Eddy Simulation (LES) method is used to model the turbulence structures of the flow. Sliding Mesh (SM) and Volume of Fluid (VOF) methods were chosen respectively to resolve the rotation of the wheel and the position of the free surface. The SM module was already validated in the past, but the VOF module needed to be validated in the present work through the simulation of free surface over a semicylindrical dam. Finally, the performance of a small 12-straight-blade HPM was simulated with caffa3d, with quite satisfactory results. Some issues of the solver yet need to be solved before other HPM with more complex designs could be studied.
Numerical Modeling of Beach Well Intake as Pre-Treatment for a Desalination Plant
Authors: Alagha Omar , Abuhajar Osama
Published: August 2020

Pre-treatment of seawater plays a critical role in removing colloidal particles, algae, sediment, and microbes, which could adversely affect the desalination process. This study focused on the utilization of the natural process of infiltration by beach wells to pre-treat the intake water for the desalination process. The scope of the study was achieved by drilling two beach wells at Al-Khobar and Jubail sites at the Arabian Gulf of Saudi Arabia at 50 m depth each. In addition to that, a total of eight monitoring wells were drilled for pump testing. Numerical modeling was conducted using SEEP/W to investigate the properties of well water flux at the beach wells. The comprehensive physio-chemical parameters such as cation, silt density index (SDI), total dissolved solids (TDS), total suspended solids (TSS), chemical oxygen demand (COD), total organic carbon (TOC), salinity, and alkalinity were analyzed for a quality assessment concerning the actual seawater. Preliminary experimental results show a reduction of the targeted parameters and indicate that beach well sand filtration in the Eastern Province would be a valuable pre-filtration step in reverse osmosis (RO)-based drinking water production systems. The water flux values for both sites were 0.0197 and 0.0208 m3/s/m2, respectively, which corresponds to 72 m3/h/m2 and 1356.48 m3/h/m2. In terms of the rate of pumping flow, the model suggests production can be increased by 20 and 53 times the measured production of the Jubail and Al-Khobar sites, respectively. The experimental results of water parameters, such as cation, SDI, TDS, TSS, etc., indicate that beach well sand filtration in the Eastern Province would be a valuable pre-filtration step in reverse osmosis drinking water production systems.
Quantification of Neonicotinoid Pesticides in Six Cultivable Fish Species from the River Owena in Nigeria and a Template for Food Safety Assessment
Authors: Adegun Ayodeji O. , Akinnifesi Thompson A. , Ololade Isaac A. , Busquets Rosa , Hooda Peter S. , Cheung Philip C.W. , Aseperi Adeniyi K. , Barker James
Published: August 2020

The Owena River Basin in Nigeria is an area of agricultural importance for the production of cocoa. To optimise crop yield, the cocoa trees require spraying with neonicotinoid insecticides (Imidacloprid, Thiacloprid Acetamiprid and Thiamethoxam). It is proposed that rainwater runoff from the treated area may pollute the Owena River and that these pesticides may thereby enter the human food chain via six species of fish (Clariasgariepinus, Clariasanguillaris, Sarotherodongalilaeus, Parachannaobscura, Oreochromisniloticus and Gymnarchusniloticus) which are cultured in the river mostly for local consumption. This work aims to establish a working method to quantify the likely levels of the insecticides in the six species of fish, firstly by undertaking a laboratory-based study employing the QuEChERS method to extract the four neonicotinoids from fish purchased in marketplace in the UK, spiked with known quantities of the pesticide and using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) as the detection method; secondly, by using these samples to optimise the detection method for very low levels of pesticides, then applying the optimised techniques to the analysis of three of each six species of fish taken from the Owena River. A significant benefit of this combined technique is that only small samples of fish are required. Success with this part of the study showed that very low concentrations of the insecticides could be detected in fish muscle. The third aim is to apply a simple quantitative risk assessment model using the data sets obtained, together with information about daily diet, human body weight and recommended safety limits of pesticides in food to illustrate how human health may be affected by the consumption of these fish. The multiple determinations of neonicotinoids in edible fishes in Nigeria are pioneer research and fill a gap in addressing the relationship between waterborne pesticides and food quality in the country. Fundamentally, this work is an exercise to demonstrate the applicability of the aforementioned instrumental method of analysis to fish muscle, which requires only a small sample size of fish; a large number of fish is not required for a proof of concept, in this case. Although not a monitoring programme for the whole Owena River Basin ecosystem per se, this work successfully demonstrates the technical feasibility of a system of chemical analysis and establishes the foundation for ecological surveys in the immediate future. Parameters involving exposures to xenobiotics in ecotoxicological modelling can now be expressed in terms of both mass and molar concentrations of a chemical in animal tissues if so desired.
Management aspects of accounting for biological assets and agricultural products
Authors: Alborov Rolan , Khoruzhy Lyudmila , Kontsevaya Stanislava , Kontsevoy Gregory
Published: August 2020

Agricultural activity is a strategic direction of the work of agricultural organizations, ensuring food independence and security of the country. In this regard, in modern conditions there is an objective need to improve the management of biotransformation of biological assets and its accounting and control functions. The work defines the objects of management and accounting of agricultural activity: biological assets; agricultural products; income, expenses and financial results from biotransformation of biological assets; government grant related to a biological asset measured at fair value less costs to sell. Recommendations are proposed on the determination and analysis of changes in the fair value of biological assets less costs to sell due to changes in unit prices and the amount of these assets. In addition, methodological aspects of monitoring the effectiveness of the use of biological assets and the production of agricultural products collected from them are identified. Each of these indicators provides indicative indicators, methods of calculation and comparison with similar indicators of the base period or planning. The following are methods for determining individual indicators from the proposed system that allow organization managers at all levels of internal management to make scientifically sound economic decisions to improve the efficiency of the processes of biological transformation of biological assets and agricultural production in agricultural organizations.
The main directions of internal audit when checking the accounting of export transactions
Authors: Safonova Margarita , Gribushenkova Valentine
Published: August 2020

Internal audit of foreign economic activity, in particular export operations, is one of the most difficult and time-consuming areas of audit. This is justified by a whole set of normative and legislative acts that regulate the accounting and support of export operations, as well as the absence of clearly regulated accounting rules for a number of business processes. The main goal of the study is to develop a methodology for internal audit of foreign trade operations. The article highlights the information base for auditing export operations, proposes an audit program, which defines the main areas of audit, including areas of increased risk of corruption of credentials. In the conclusion, it is concluded that the application of the proposed recommendations in practice will allow obtaining better audit results and will increase the reliability of the issued reporting.
Methodical approaches to analysis of owned and loan capital of agricultural organizations
Authors: Bondina Natalia , Bondin Igor
Published: August 2020

In the article, the authors note that the main sources of capital formation are own funds. The authors examined in detail the movement of equity and borrowed capital. Factors have been established where the indicator of profitability of sales had a negative impact. The authors analyzed their own and borrowed capital using the method of coefficients. As a result, the financial independence ratio indicates that the organization will cover all liabilities at its own expense. The organization is financially independent of borrowed funds and it has enough own funds to finance current activities. A low value of the financial leverage ratio indicates a missed opportunity to increase the return on equity by attracting borrowed funds into its activities.
A Review of the Associations between Dietary Fiber Intake and Cancer Prevention or Prognosis
Authors: Xie Ying , Ren Yu Wei , Li Xiao Ling , Li Zeng Ning
Published: August 2020

The increase in tumor incidence is closely related to dietary factors. In recent years, many researchers have carried out in-depth research to investigate whether increasing the intake of dietary fiber can prevent tumors and improve the prognosis, but the results have been unclear. We herein searched the literature in common academic databases and incorporated and summarized the relevant articles. The literature clearly indicates that dietary fiber can protect against the following cancers: colorectal cancer, breast cancer, pancreatic cancer, ovarian cancer, and head and neck cancer. There is also evidence that dietary fiber intake can exert protective effects against cancers of the liver, lung, stomach, small bowel, kidney, and esophagus, as well as lymphoma, but the data have so far been relatively limited. The effects on endometrial cancer and prostate cancer still remain uncertain. In terms of the effects on the cancer prognosis, dietary fiber does not appear to have an impact on colorectal cancer or breast cancer. Although more research is needed for some kinds of cancer, it is clear that increasing the intake of dietary fiber is beneficial for preventing the occurrence and development of several major types of cancer, with no major adverse effects. We therefore recommend that most of individuals increase their intake of dietary fiber.