DI System Research Articles

Evaluation of three irrigation application systems for watermelon production in the Texas High Plains

AbstractAbout 90% of the Texas High Plains area depends on the water supply from the Ogallala aquifer. The decline of the Ogallala water table raises a concern for the sustainability of producing the traditional irrigated field crops due to their high water demand. Thus, diversifying cropping systems may be a solution. However, about 70% of the irrigated cropland uses center pivots that may negatively impact specialty crop quality. Thus, a 3‐year experiment was conducted to assess the potential of using mobile drip irrigation (MDI) to produce fresh watermelon compared to center pivot sprinkler irrigation using low‐elevation spray application (LESA), and surface drip irrigation with plastic mulch (DI). The study evaluated the effects of irrigation systems on crop yield, fruit quality, physiological responses, water use efficiency (WUE), and irrigation use efficiency (IUE). On average, plants under MDI had higher yields (106 Mg ha−1) than those under DI (70 Mg ha−1) and LESA (68 Mg ha−1). Plants under MDI and DI also had more fruits per plant (1.9) than those under LESA (1.4). The higher yield was associated with higher biomass and photosynthetic function. In general, fruit quality was not affected by irrigation system. In addition, plants under MDI system showed a higher WUE and IUE, and less water stress than those under LESA and DI systems. Results of this study suggest that irrigating under an MDI system is a good alternative for growers in the Texas High Plains that aim to diversify their cropping system with high‐value vegetable crops such as watermelon (Citrullus lanatus).

Deep Learning Based Blood Abnormalities Detection As a Tool for Vexas Syndrome Screening

Introduction The VEXAS syndrome (vacuoles, E1 enzyme, X-linked, auto-inflammatory, somatic) described in 2020 caused by mutations of the UBA1 gene, displayed a large pleomorphic array of clinical and biological features. Nevertheless, these criteria do not allow to discriminate VEXAS from other myeloid malignancies on complete blood count + differential, notably due to the absence of peripheral blood characterization of the disease. This study aimed at singling out dysplastic features indicative of VEXAS among peripheral blood (PB) polymorphonuclears (PMN) from VEXAS patients compared to healthy patients and myelodysplastic (MDS) patients. As such task is tedious and subject to operator bias, a multicentric dataset has been used to design a deep learning algorithm for automatic detection of these features, finally tested on an external validation cohort. Patient, material and methods Patients written consents were obtained and five academic centers (number from 1 to 5) were involved in this 3 steps study. Firstly, 3 academic centers (number 1 to 3) enrolled 20 patients distributed as follow: 9 patients with UBA1 mut and 6 patients UBA1 wt with no other genetic mutation as well as 5 samples from MDS patients. A total of 25 PB smears and especially PMN images were gathered and screened for various abnormalities. Two independent morphologists blindly quantified PMN predefined characteristics. This dataset of 2,824 multilabelled PMN was evaluated and tested by a two-sample Wilcoxon Rank Sum test for statistical significance between UBA1 mut and the others. Secondly, in order to automate the detection of these significant features on PMN images, a convolutional neural network (CNN) was trained using a multicentric image dataset gathered from 4 academic centers (number 2 to 5). Patients were selected based on clinical and biological symptoms suggesting VEXAS syndrome, namely fever, skin lesions, chondrites, vasculitis and/or anemia. After evaluation of the UBA1 mutation status, this multicentric cohort was separated into confirmed VEXAS (n = 19) and UBA1 WT (n=20). A total of 6,615 annotated PMN images were collected from DI systems (Cellavision ®, Lund, Sweden) with 1 to 12 PB smears per patient, yielding a 48 UBA1 mut and 33 UBA1 wt smears. All patients were males, the median age was 74 year-old (IQR 67-77) and that of control patients 72 year- old (61-79). Finally, the CNN was evaluated on an external cohort from another academic hospital (center 1), including inflammatory patients, and patients screened for VEXAS syndrome for a total cohort of 15 patients and 1,887 images. Results Four specific abnomalities were observed in PMNs from VEXAS patients as compared with healthy or myelodysplastic controls. The automatic recognition of anomalies was then cast in a multilabel classification task, where each PMN image could be assigned to one or more labels during interference. In order to take into account this specificity, a CNN was trained, composed of different layers of convolutions and pooling (Figure1). The model was set-up to output an independent binary prediction for the presence or absence of each of the four anomalies of interest. Automatic detection of these 4 anomalies by the proposed model yielded area under the curve (AUC) of 0.827; 0.837; 0.927 and 0.947 (Figure 2). Regarding the general performance on the external validation cohort, the CNN achieved a Hamming loss of 0.141, and macro and micro F1 scores of 0.588 and 0.668 respectively. Discussion This study suggests that computer-assisted analysis of PB smears, focusing on suspected VEXAS cases, could provide valuable insights to determine which patients should undergo molecular testing. A deep-learning approach leveraging previously identified peripheral blood indicators and automatic analyzers is thus presented, which can help hematologists orient their suspicion before initiating further analysis.

Varietal Differences in the Root Systems of Rice (Oryza sativa L.) under Drip Irrigation with Plastic Film Mulch

With the escalating water scarcity in agriculture, a novel water-saving technique has emerged: drip irrigation with plastic film mulch (DI). Root function is crucial for sustaining rice production, and understanding its response to DI is essential. However, few studies have evaluated root systems in rice varietals and examined which kind of root system contributes to improving rice grain yield and water productivity in DI. If varietal differences of root reactions for water regimes were made clear, it might be more effective to find suitable varieties for DI and to improve grain yield in the DI system. To fill this knowledge gap, we conducted a two-year field experiment comparing two irrigation systems: continuous flooding (CF) and DI. We analyzed their effectiveness with four rice cultivars, including upland, F1 lowland, animal feed lowland, and lowland cultivars. Vertical root distribution, root bleeding rate, photosynthetic-associated parameters, water productivity, and yield performance were analyzed. In our study, the average grain yield of cultivars in the DI system (6.4 t/ha) was equivalent to those in the CF system (6.6 t/ha). The average water productivity under DI (0.34–0.75 kg m−3) demonstrated significant water-saving potential, saving approximately 35% of the total water supplied, resulting in higher water productivity compared to CF (0.27–0.51 kg m−3). Among the cultivars, the deep root weight of the upland cultivar significantly increased by 51% under DI compared to CF. The deep root ratio was positively correlated with the transpiration rate, grain yield, and water productivity, suggesting its contribution to high transpiration, thus maintaining a high carbon assimilation rate that results in high yield and water productivity. Therefore, deep roots are a notable trait corresponding to high yield under DI, and should be considered for the development of rice growth models for DI and the breeding of aerobic-adapted cultivars.

Effects of Varying Excess Air Ratios on a Hydrogen-fueled Spark Ignition Engine with PFI and DI Systems under Low-load Conditions

Effects of Varying Excess Air Ratios on a Hydrogen-fueled Spark Ignition Engine with PFI and DI Systems under Low-load Conditions

(Invited) MEA Technologies for PEM Electrolyzers: Overview and Perspectives

Hydrogen has gained increasing attention recently as an alternative energy carrier leading towards a sustainable hydrogen economy [1]. Green hydrogen has less pollution (water as the only byproduct) and higher energy density than its counterpart fossil fuels. Additionally, it has much higher refueling speed than lithium-ion batteries, which makes it’s more suitable for mobility applications.Proton exchange membrane (PEM) water electrolysis is one of the most popular approaches for green hydrogen generation due to its high efficiency and high differential pressure operation capability [2]. The membrane electrode assembly (MEA) is the core of a PEM electrolyzer in which water molecules are spilt into hydrogen and oxygen molecules. In this overview, the challenges and paths regarding the MEA materials, operation/diagnosis/maintenance, and final recycling will be discussed.An electrolyzer MEA contains an anode and cathode made of platinum group metal (PGM) catalysts, a perfluorosulfonic acid (PFSA) membrane, and other gasketing materials. PGM catalysts are a major source of the cost of the PEM electrolyzer stack. Ir black based catalysts have been used for decades in the PEM electrolyzer industry. Due to the high cost and scarcity of Ir, efforts have been dedicated to reducing the catalyst loading and developing highly active catalysts [3]. The membrane is another major component of a PEM electrolyzer. 5 mil and 7 mil thick membranes have been used in electrolyzer industries. However, the ionic resistive losses of these relatively thick PEMs significantly reduce the efficiency of the MEA. Hence, reducing membrane thickness has been a central topic for PEM electrolyzer membrane development. With the progressive thinning of the PEM, the hydrogen gas crossover will become significant, which will compromise the safe operation of a PEM electrolyzer system. An effective gas recombination layer in the PEM is therefore urgently needed to mitigate the resulting higher hydrogen crossover. Additionally, the mechanical stresses imposed due to operation at high differential pressure operation (up to 40 bar) increases the attractiveness of a reinforcement layer.The unique properties of the membrane and catalysts in an MEA also require ultra-pure feed water. However, this cannot always be guaranteed. Metal ions will leach out from system plumbing and the DI system can’t always effectively remove all ions from tap water. The contamination will also poison the catalysts in an MEA. It is therefore critical to establish a universal method to efficiently identify the issue and recover the MEA performance.It is expected that the MEA can last 60k to 90k hours [4]. Though functionality may be compromised at the this point, the value in the PGM catalysts, and to a lesser extent membrane, and other carbon-based materials [5] remains. MEA recycling thus needs to be considered at the very early stage of the large-scale PEM electrolyzer application. Tradition calcination approaches for catalyst refinery is not optimized for PEM MEAs due to the presence of the PFSA membrane. The burning of MEAs will not only waste costly PFSA material but also poses a threat to the environment due to carbon and fluoride emissions. Current research efforts have focused on catalyst recycling and reuse/repurpose of PFSA based materials.[1] Oliveira, A. M., Beswick, R. R. & Yan, Y. A green hydrogen economy for a renewable energy society. Current Opinion in Chemical Engineering 33, 100701 (2021).[2] Ayers, K. et al. Perspectives on low-temperature electrolysis and potential for renewable hydrogen at scale. Annual review of chemical and biomolecular engineering 10 (2019).[3] Mittelsteadt, C. (Invited) Ir Strangelove: Or How I Learned to Stop Worrying and Embrace the PEM. ECS Meeting s MA2022-01, 1335-1335 (2022).[4] Schmidt, O., Future cost and performance of water electrolysis: an expert elicitation study. International journal of hydrogen energy 42 (2017), 30470-30492.[5] Sverdrup, H. U. & Ragnarsdottir, K. V. A system dynamics model for platinum group metal supply, market price, depletion of extractable amounts, ore grade, recycling and stocks-in-use. Resources, Conservation and Recycling 114, 130-152 (2016)

Effect of planting and irrigation management strategies on growth, yield and water productivity of indica rice in Iran

Abstract One of the most important problems for rice production is the high water need of this plant. Therefore, the use of modern technologies to increase water-saving in paddy fields is critical to global food security. Hence, the present study aimed to evaluate the effects of different planting methods and irrigation systems on growth, yield and water productivity in rice. The experiment was arranged as a split-plot in a randomized complete block design with three replications. The experimental treatments included the main plot assigned to three planting methods (transplanting at puddled bed [TPB], transplanting at non-puddled bed [TNPB], and direct-seeded rice [DSR]) and the sub-plot assigned to three irrigation systems (continuous flooding irrigation (CFI), alternate wetting and drying [AWD], and drip irrigation [DI]). The results showed that the highest grain yield (3962.7 kg.ha−1) and more-water-saving (17.3%) was achieved in the TPB treatment. Total water productivity for TPB, TNPB, and DSR methods were calculated to be 0.56, 0.43, and 0.34 kg.m−3, respectively. Grain yield in CFI (3457.6 kg.ha−1) and AWD (3410.3 kg.ha−1) systems was significantly higher than DI treatment (3150.7 kg.ha−1), while no significant difference was observed between CFI and AWD treatments in terms of rice production. However, the AWD system increased water-saving by 24.8% compared with CFI. Our results highlight that combined application of AWD system and TPB method has a great potential to reduce total water input without negatively affecting yield.

Fundamentally Reforming the Di System: Evidence from German Notch Cohorts

Fundamentally Reforming the Di System: Evidence from German Notch Cohorts

A SWOT analysis of artificial intelligence in diagnostic imaging in the developing world: making a case for a paradigm shift

Abstract Diagnostic imaging (DI) refers to techniques and methods of creating images of the body’s internal parts and organs with or without the use of ionizing radiation, for purposes of diagnosing, monitoring and characterizing diseases. By default, DI equipment are technology based and in recent times, there has been widespread automation of DI operations in high-income countries while low and middle-income countries (LMICs) are yet to gain traction in automated DI. Advanced DI techniques employ artificial intelligence (AI) protocols to enable imaging equipment perceive data more accurately than humans do, and yet automatically or under expert evaluation, make clinical decisions such as diagnosis and characterization of diseases. In this narrative review, SWOT analysis is used to examine the strengths, weaknesses, opportunities and threats associated with the deployment of AI-based DI protocols in LMICs. Drawing from this analysis, a case is then made to justify the need for widespread AI applications in DI in resource-poor settings. Among other strengths discussed, AI-based DI systems could enhance accuracies in diagnosis, monitoring, characterization of diseases and offer efficient image acquisition, processing, segmentation and analysis procedures, but may have weaknesses regarding the need for big data, huge initial and maintenance costs, and inadequate technical expertise of professionals. They present opportunities for synthetic modality transfer, increased access to imaging services, and protocol optimization; and threats of input training data biases, lack of regulatory frameworks and perceived fear of job losses among DI professionals. The analysis showed that successful integration of AI in DI procedures could position LMICs towards achievement of universal health coverage by 2030/2035. LMICs will however have to learn from the experiences of advanced settings, train critical staff in relevant areas of AI and proceed to develop in-house AI systems with all relevant stakeholders onboard.

Irrigation Scheduling and Production of Wheat with Different Water Quantities in Surface and Drip Irrigation: Field Experiments and Modelling Using CROPWAT and SALTMED

Water is a key factor in global food security, which is critical to agriculture. The use of mathematical models is a strategy for managing water use in agriculture, and it is an effective way to predict the effect of irrigation management on crop yields if the accuracy of these models is demonstrated. The CROPWAT and SALTMED models were tested in this study, with water quantities applied to surface and drip irrigation (SI and DI) systems to estimate irrigation scheduling and wheat yield. For this purpose, field experiments were conducted for two consecutive years to study the effects of irrigation water levels of 80%, 100%, and 120% crop evapotranspiration (I80, I100, and I120) on the yield and water productivity (WP) of wheat in SI and DI systems. Irrigation treatments affected yield components such as plant height, number of spikes, spike length, and 1000-kernel weight, though they were not statistically different in some cases. In the I80 treatment, the biological yield was 12.8% and 8.5% lower than in the I100 and I120 treatments, respectively. I100 treatment under DI resulted in the highest grain yield of a wheat crop. When DI was applied, there was a maximum (22.78%) decrease in grain yield in the I80 treatment. The SI system was more water-consuming than the DI system was, which was reflected in the WP. When compared with the WP of the I80 and I100 treatments, the WP was significantly lower (p < 0.05) in the I120 treatment in the SI or DI system. To evaluate irrigation scheduling and estimate wheat yield response, the CROPWAT model was used. Since the CROPWAT model showed that increasing irrigation water levels under SI for water stress coefficient (Ks) values less than one increased deep percolation (DP), the I120 treatment had the highest DP value (556.15 mm on average), followed by the I100 and I80 treatments. In DI, I100 and I120 treatments had Ks values equal to one throughout the growing seasons, whereas the I80 treatment had Ks values less than one during wheat’s mid- and late-season stages. The I100 and I80 treatments with DI gave lower DP values of 93.4% and 74.3% compared with that of the I120 treatment (on average, 97.05 mm). The I120 treatment had the lowest irrigation schedule efficiency in both irrigation systems, followed by the I100 and I80 treatments. In both seasons, irrigation schedule deficiencies were highest in the I80 treatment with DI (on average, 12.35%). The I80 treatment with DI had a significant yield reduction (on average, 21.9%) in both seasons, while the irrigation level treatments with SI had nearly the same reductions. The SALTMED model is an integrated model that considers irrigation systems, soil types, crops, and water application strategies to simulate soil water content (SWC) and crop yield. The SALTMED model was calibrated and validated based on the experimental data under irrigation levels across irrigation systems. The accuracy of the model was assessed by the coefficients of correlation (R), root mean square errors (RMSE), mean absolute errors (MAE), and mean absolute relative error (MARE). When simulating SWC, the SALTMED models’ R values, on average, were 0.89 and 0.84, RMSE values were 0.018 and 0.019, MAE values were 0.015 and 0.016, and MARE values were 8.917 and 9.133%, respectively, during the calibration and validation periods. When simulating crop yield, relative errors (RE) for the SALTMED model varied between −0.11 and 24.37% for biological yield and 0.1 and 19.18% for grain yield during the calibration period, while in the validation period, RE was in the range of 3.8–29.81% and 2.02–25.41%, respectively. The SALTMED model performed well when simulating wheat yield with different water irrigation levels under SI or DI.

Insurance of Bank Deposits: Some Issues

Bank deposit insurance is different from other insurance business. Apart from protecting individual’s asset it has a broader perspective, i.e., ensuring country’s financial stability. International authorities strongly advocate for installing DI system in each and every country. It has some features which are unique to this type of insurance and has made its design a complicated task. IMF has developed some basic guidelines which need to be followed before installing a DI system. India has a DI system but its function has been limited so far as majority of the banks enjoy implicit guarantee. In the emerging privatised era the DICs will have to play a more significant role.

Molecular blood group screening in Omani blood donors.

Blood group genotyping has been used in different populations. This study aims at evaluating the genotypes of common blood group antigens in the Omani blood donors and to assess the concordance rate with obtained phenotypes. Blood samples from 180 Omani donors were evaluated. Samples were typed by serological methods for the five blood group systems MNS, RH (RHD/RHCE), KEL, FY and JK. Samples were genotyped using RBC-FluoGene vERYfy eXtend kit (inno-train©). Predicted phenotypic variants for 70 red blood cell antigens among the MNS, RH (RHD/RHCE), KEL, FY, JK, DO, LU, YT, DI, VEL, CO and KN blood group systems were assessed. Simultaneous phenotype and genotype results were available in 130 subjects. Concordance rate was >95% in all blood group systems with exception of Fy(b+) (87%). Homozygous GATA-1 mutation leading to erythroid silencing FY*02N.01 (resulting in the Fy(b-)ES phenotype) was detected in 81/112 (72%) of genotyped samples. In addition, discrepant Fyb phenotype/genotype result was obtained in 14/112 samples; 13 of which has a heterozygous GATA-1 mutation and one sample with a wild GATA genotype. D and partial e c.733C>G variants expressing the V+VS+ phenotype were found in 22/121 (18.2%) and 14/120 (11.7%) of the samples, respectively. Di(a-b+), Js(a-b+), Yt(a+b-) and Kn(a+b-) genotype frequencies were 99.4%, 95.8%, 91.9% and 97.7%, respectively. In conclusion, we report a high frequency of FY*02N.01 allele due to homozygous c.-67T>C GATA-1 single-nucleotide variation. This is the first study reporting the detailed distribution of common and rare red cell genotypes in Omani blood donors.

Comparison of aerobic rice cultivation using drip systems with conventional flooding

AbstractIn this study, yield and water productivity response of rice to various irrigation levels applied with subsurface and surface drip systems in 2019 and 2020 in the Mediterranean Region of Turkey was evaluated in comparison with conventional flooding (CF). The treatments consisted of two irrigation methods namely surface drip (DI) and subsurface drip systems (SDI), three irrigation levels designated as plant pan coefficients (I1.00: Evaporation from Class A pan (Ep) × 1.00; I1.25: Ep × 1.25 and I1.50: Ep × 1.50) and CF as control. The effects of drip systems and coefficients on yield and yield components were statistically significant (P < 0.01). DI produced higher yield than SDI. CF produced significantly greater yield than both DI and SDI systems. With two drip systems, average water savings of 60.5% in I1.00, 54.5% in I1.25 and 49% in I1.50 were achieved as compared to CF. However, yield reductions of 15% in I1.50, 20% in I1.25, 29% in I1.00 were observed for DI; corresponding values for SDI were 20, 28 and 44%, respectively. Drip irrigation in aerobic rice production system had almost twice the water productivity based on total irrigation water applied (WPI) or total water input (irrigation + rainfall) (WPI+P) compared with CF. During the study years, the highest WPI and WPI+P values were found in DI-I1.00 (0.81–0.73 kg/m3) and (0.85 and 0.74 kg/m3), respectively. In conclusion, DI-I1.50 treatment is recommended for sustainable aerobic rice production since DI-I1.50 resulted in water saving of 49% but yield decrease of 15% as compared to CF.

A Comparative Analysis of Root Growth Modules in HYDRUS for SWC of Rice under Deficit Drip Irrigation

Root distribution during rice cultivation is a governing factor that considerably affects soil water content (SWC) and root water uptake (RWU). In this study, the effects of activating root growth (using growth function) and assigning a constant average root depth (no growth during simulation) on SWC and RWU for rice cultivation under four deficit drip irrigation treatments (T90, T80, T70, and T60) were compared in the HYDRUS-2D/3D model version 3.03. A secondary objective was to investigate the effect of applied deficit irrigation treatments on grain yield, irrigation water use efficiency (IWUE), and growth traits of rice. The simulated DI system was designed to reflect a representative field experiment implemented in El-Fayoum Governorate, Egypt, during two successive seasons during 2017 and 2018. The deficit treatments (T90, T80, T70, and T60) used in the current study represent scenarios at which the first irrigation event was applied when the pre-irrigation average SWC within the upper 60 cm of soil depth was equal to 90%, 80%, 70%, and 60% of plant-available water, respectively. Simulation results showed that as water deficiency increased, SWC in the simulation domain decreased, and thereby, RWU decreased. The average SWC within the root zone during rice-growing season under different deficit treatments was slightly higher when activating root growth function than when considering constant average root depth. Cumulative RWU fluxes for the case of no growth were slightly higher than for the case of root growth function for T90, T80, and T70 accounting for 1289.50, 1179.30, and 1073.10 cm2, respectively. Average SWC during the growth season (24 h after the first irrigation event, mid-season, and 24 h after the last irrigation event) between the two cases of root growth was strongly correlated for T90, T80, T70, and T60, where r2 equaled 0.918, 0.902, 0.892, and 0.876, respectively. ANOVA test showed that there was no significant difference for SWC between treatments for the case of assigning root growth function while the difference in SWC among treatments was significant for the case of the constant average root depth, where p-values equaled 0.0893 and 0.0433, respectively. Experimental results showed that as water deficiency decreased, IWUE increased. IWUE equaled 1.65, 1.58, 1.31, and 1.21 kg m−3 for T90, T80, T70, and T60, respectively. Moreover, higher grain yield and growth traits of rice (plant height, tillers number plant−1, panicles length, panicle weight, and grain number panicles−1) were obtained corresponding to T90 as compared with other treatments. Activating the root growth module in HYDRUS simulations can lead to more precise simulation results for specific dates within different growth stages. Therefore, the root growth module is a powerful tool for accurately investigating the change in SWC during simulation. Users of older versions of HYDRUS-2D/3D (version 2.05 and earlier) should consider the limitations of these versions for irrigation scheduling.

Life-cycle assessment of two sewage sludge-to-energy systems based on different sewage sludge characteristics: Energy balance and greenhouse gas-emission footprint analysis

Anaerobic digestion and incineration are widely used sewage sludge (SS) treatment and disposal approaches to recovering energy from SS, but it is difficult to select a suitable technical process from the various technologies. In this study, life-cycle assessments were adopted to compare the energy- and greenhouse gas- (GHG) emission footprints of two sludge-to-energy systems. One system uses a combination of AD with incineration (the AI system), whereas the other was simplified by direct incineration (the DI system). Comparison between three SS feedstocks (VS/TS: 57.61 -73.1 ds.%) revealed that the AI system consistently outperformed the DI system. The results of sensitivity analyses showed that the energy and GHG emission performances were mainly affected by VS content of the SS, AD conversion efficiency, and the energy consumption of sludge drying. Furthermore, the energy and GHG emission credit of the two systems increased remarkably with the increase in the VS content of the SS. For the high-organic-content sludge (VS/TS: 55%–80%), the energy and GHG emission credit of the AI system increase with the increase of AD conversion efficiency. However, for the low organic content sludge (VS/TS: 30%–55%), it has the opposite effect. In terms of energy efficiency and GHG performance, the AI system is a good choice for the treatment of high-organic-content sludge (VS/TS>55%), but DI shows superiority over AI when dealing with low organic content sludge (VS/TS<55%).

Effects of different surface and subsurface drip irrigation levels on growth traits, tuber yield, and irrigation water use efficiency of potato crop

Increased water demands and climate change have reduced agricultural water resources in areas that experience water shortages. Therefore, a field experiment was conducted in an arid region of Saudi Arabia to evaluate the effects of two drip irrigation systems [surface (DI) and subsurface (SDI)] and three irrigation levels [100%, 70%, and 50% of crop evapotranspiration (I100, I70, and I50, respectively)] on the growth traits, tuber yield, and irrigation water use efficiency (IWUE) of potato (Solanum tuberosum L.) during the 2017 and 2018 growing seasons. θv was 13.74 and 23.85% lower under the DI system and 11.90 and 24.14% lower under the SDI system with the I70 and I50 treatments, respectively, than with the I100 treatment, and was also lower under the DI system than under the SDI system. The fresh and dry vegetative parts of the plants were heavier with the I100 treatment under the SDI system than with the I70 and I50 treatments under the DI system, and the leaf area indexes were also significantly lower with I70 and I50 than with I100 but were not affected by the irrigation system. The fresh and dry tuber yields were lowest with the I50 treatment (23.97 and 3.93 Mg ha−1, respectively), followed by I70 (28.61 and 4.98 Mg ha−1, respectively), and I100 (34.43 and 6.67 Mg ha−1, respectively) and were higher under the SDI system than under the DI system. By contrast, IWUE was highest with the I50 treatment (6.49 and 7.02 kg m−3) and lowest with the I100 treatment (5.62 and 5.85 kg m−3) under the DI and SDI systems, respectively. These findings indicate that full irrigation (I100) with the SDI system maximizes potato yield but decreases IWUE, whereas integration of the SDI system with deficit irrigation is effective in improving water productivity due to less water being consumed, allowing these practices to be used under scarce water conditions.

How Does Risk-based Deposit Insurance Premium Affect Bank Risk Taking? Islamic Bank vis a vis Conventional Bank

Central banks across the world implemented deposit insurance system as a major risk management practice in the post Global Financial Crisis (2007/2008) period. This study provides insights on the efficacy of deposit insurance policy in the Malaysian market where Islamic and conventional banking co-exist. Given that Islamic banking principles inherently limitsbank risk taking ability, the study findings clearly identify the pertinent role of risk-based deposit insurance premium on mitigating potential increase bank risk in the post-financial crisis period. Using Malaysian banks data for the period 2002-2010, this study findsthat Islamic banks have lower risk appetite than conventional banks. Most importantly, after the introduction of deposit insurance system, insolvency and operational risk increasemainly for conventional banks owing to inadequate premium. This calls for policymakers to carefully consider design features for an effective risk-based DI system that is risk-premium sensitive to ensure financial stability. Other policy implications include that the risk-based deposit insurance premium would prevent regulatory arbitrage,while Shariahcomplianceprinciples preventthe Islamic banks from adjusting their risk after the introduction of a deposit insurance system. Worth mentioning is the institution of an early warning mechanism policy as well as formal cooperation in information sharing protocols among policy makers, regulators and deposit insurance organisations to minimiseoperational risk in banks.

Effect of equivalence ratio on diesel direct injection spark ignition combustion

Aviation heavy-fuel spark ignition (SI) piston engines have been paid more and more attention in the area of small aviation. Aviation heavy-fuel refers to aviation kerosene or light diesel fuel, which is safer to use and store compared to gasoline fuel. And diesel fuel is more suitable for small aviation application on land. In this study, numerical simulation was performed to evaluate the possibility of switching from gasoline direct injection spark ignition (DISI) to diesel DISI combustion. Diesel was injected into the cylinder by original DI system and ignited by spark. In the simulation, computational models were calibrated by test data from a DI engine. Based on the calibrated models, furthermore, the behavior of diesel DISI combustion was investigated. The results indicate that diesel DISI combustion is slower compared to gasoline, and the knock tendency of diesel in SI combustion is higher. For a diesel/air mixture with an equivalence ratio of 0.6 to 1.4, higher combustion pressure and faster burning rate occur when the equivalence ratios are 1.2 and 1.0, but the latter has a higher possibility of knock. In summary, the SI combustion of diesel fuel with a rich mixture can achieve better combustion performance in the engine.

Soot particles in piston-top pool fires and exhaust at 5 and 15 MPa injection pressure in a gasoline direct-injection engine

This study shows the structure of soot particles sampled directly from wall wetting-induced pool fires formed on the piston top in a spark-ignition direct-injection (SIDI) engine. Of particular interest is its variation with injection pressure considering the current trend of high-pressure DI system development to reduce engine-out particulate emissions. Thermophoretic particle sampling was performed for transmission electron microscope (TEM) imaging, which was post-processed for statistical analysis of key morphology and internal structure parameters. These include the size distribution of soot aggregates and primary particles as well as carbon-layer fringe-to-fringe gap and concentricity. With the fixed engine speed and load conditions, in-flame soot particles are compared to the exhaust particles sampled simultaneously at selected 5 and 15 MPa injection pressures corresponding to low-speed/low-load and high-speed/high-load in practical engine operation. From the TEM images and statistical analysis, it was found that more concentrated and taller pool fire developed for 5-MPa injection leads to smaller soot aggregates composed of smaller soot primary particles due to suppressed soot growth in fuel-rich flames. However, the soot particles formed in 15-MPa injection-induced pool fires are at a more reactive status evidenced by less defined core-shell boundaries and higher fringe separation. The higher soot reactivity results in enhanced soot oxidation, which explains smaller soot aggregates and primary particles found for the 15-MPa injection in the exhaust sample.

Effects of three irrigation systems on ‘Piel de sapo’ melon yield and quality under salinity conditions

The melon crop is moderately sensitive to soil salinity and, as a consequence, its yield decreases under saline conditions. Nevertheless, the exposure to moderate salinity also influences the melon quality by improving it, which offers compensation to the farmer. As a consequence, in moderately salt-affected lands, like the traditional irrigation area of the ‘Vega Baja del Segura’ (Alicante, Spain), melons are being grown. In this area the modernization of the secular irrigation system through the replacement of flood by drip systems, is currently being fostered. This fact, however, is generating some controversy, due to the known salt leaching effect that flood irrigation followed by drainage makes in the soil. In this study, the effects of three irrigation systems, namely, drip (DI), subsurface drip (SDI) and flood (FI), on soil salinity and thus, on the yield and quality of the melon, were compared. According to the results, the FI system kept the soil salt levels during the growth period at 4.1 ± 0.3 dS/m, that is, significantly lower than the 4.7 ± 0.2 dS/m attained with the DI and SDI systems. Nevertheless, the DI and, overall, SDI, provided higher and more homogenous soil moisture completely counteracting the effect of salinity as revealed by the soil water potential calculations. As a result, the SDI gave 27 ± 5 Mg/ha of total yield in comparison to 23 ± 2 Mg/ha (DI) and 20 ± 6 Mg/ha (FI). Besides, the SDI system reduced the number of damaged melons, thus additionally contributing to the significant higher marketable yield of the SDI (25 ± 4 Mg/ha) in comparison to the DI (20 ± 1 Mg/ha) and the FI (19 ± 7 Mg/ha). On the contrary, in the SDI treatment the fruit soluble solids content, tritatable acidity and pulp firmness decreased a bit, however, in the sensory evaluation no differences among irrigation treatments were observed.

Research on a chip scale atomic clock driven GNSS/SINS deeply coupled navigation system for augmented performance

Chip scale atomic clock (CSAC) is a recently developed low-profile atomic frequency reference device. Researchers have demonstrated CSAC was able to improve the accuracy of Global navigation satellite system (GNSS) receiver positioning results. However, the work was conducted using scalar tracking loops (STL). It is meaningful to investigate CSAC augmented vector tracking loop (VTL), since the VTL has different architecture with STL. Thus, in this paper, the authors investigated a CSAC driven VTL_DI system for exploring CASC impact on VTL. Firstly, the authors explored 1) whether VTL_DI could operate without regarding clock offset and drifts as VTL_DI integration filter state variables, and 2) whether VTL_DI could provide reliable position with only three satellites in view. Secondly, side-by-side comparative field tests were conducted to evaluate performance improvement: by solution A: VTL_DI supported by CSAC and solution B: a temperature compensated crystal oscillator (TXCO) with more than four satellites and three satellites in view scenarios. It was discovered that the CSAC could enhance the position performance, even if amount of satellites were fewer than four in view. However, VTL_DI system could not guarantee its positioning accuracy without clock offset as state variable, which was different from STL_DI system.