Hasil untuk "Irrigation engineering. Reclamation of wasteland. Drainage"

Willem F. Vlotman

ABSTRACT A sunset industry is an industry in decline, one that has passed its peak or boom periods. The irrigation industry shows, on a small scale, to be in decline, but most of the irrigation schemes in the industry seem to be doing well. Typically, the irrigation schemes that have adequate drainage, either natural or artificial are not in a sunset phase. A drainage system market research report of 2024, which considered business opportunities, growth and trends of crucial drainage market segments based on product type (channel/trench drains, French drain systems, catch basins, dry well drainage systems, drain emitters, etc.), shows substantial growth of the drainage industry worldwide. Investigation of both irrigation and drainage, including schemes, materials, products, companies, professional organisations (ASABE, ASCE and ICID), journal publications (recent: 2020–2024) and books (1999 and 2020), resulted in a plethora of materials and information that overall show that neither the irrigation nor the drainage industry is in a sunset phase or is likely to be in the future.

Nasir U. Eisty, Jeffrey C. Carver, Johanna Cohoon et al.

In the evolving landscape of scientific and scholarly research, effective collaboration between Research Software Engineers (RSEs) and Software Engineering Researchers (SERs) is pivotal for advancing innovation and ensuring the integrity of computational methodologies. This paper presents ten strategic guidelines aimed at fostering productive partnerships between these two distinct yet complementary communities. The guidelines emphasize the importance of recognizing and respecting the cultural and operational differences between RSEs and SERs, proactively initiating and nurturing collaborations, and engaging within each other's professional environments. They advocate for identifying shared challenges, maintaining openness to emerging problems, ensuring mutual benefits, and serving as advocates for one another. Additionally, the guidelines highlight the necessity of vigilance in monitoring collaboration dynamics, securing institutional support, and defining clear, shared objectives. By adhering to these principles, RSEs and SERs can build synergistic relationships that enhance the quality and impact of research outcomes.

Ramin Fazloula, Shadi Saraf, Javad Vejahat et al.

Today, the optimal use of water in various sections to increase productivity and reduce losses is one of the basic assumptions in consumption management. Therefore, in the present research, the concept of productivity in different water consumption sections, including groundwater, drinking water, and special attention to chemical properties in the sewage treatment plant in Sari City has been investigated. In each section, using the appropriate algorithm, the available data has been evaluated to measure productivity.  In the sewage treatment section, the analysis of effective parameters in Sari City sewage treatment was performed in two methods Artificial Neural Network and Wavelet. The output results of these models showed that due to the high value of the R2 statistic, there is an acceptable and direct relationship between the measured and estimated characteristics. In the groundwater sector, according to the results obtained, the wavelet network performed better in estimating the desired variables than the ANN method. In the water distribution network section, the results of wavelet analysis and the outputs of the WaterGems software revealed that the deterioration of the studied water distribution network plays a significant role in losses and reduced productivity, in such a way that about 47 percent of the water entering the network is out of reach and wasted in different ways.

علیرضا زارعی قورخودی, علی شاهنظری

هدف از این مطالعه اثرات تشکیل بازارهای آب بر ارتقای بهره‌وری آب در حوضه آبریز تجن می‌باشد. در این پژوهش از یک سیستم مدل‌سازی، مدل برنامه‌ریزی ریاضی و تابع هدف حداکثرسازی سود در محیط زبان برنامه‌نویسی متلب استفاده شد. پس از شبیه‌سازی تشکیل بازار آب، تأثیر آن بر شاخص‌های بهره‌وری فیزیکی و اقتصادی آب در دو گروه شامل مزارع بدون محدودیت آب (گروه A) و مزارع با محدودیت آب (گروه B) موردارزیابی قرار گرفت. براساس نتایج، تشکیل بازار آب منجر به افزایش 13 درصد سود در گروه (A) و 30 درصد سود در گروه (B) می‌شود. با توجه به نتایج، تشکیل بازار آب میزان مصرف آب در مزارع نماینده (A) و (B) را به‌ترتیب کاهش و افزایش می‌دهد. نتایج ارزیابی شاخص‌های بهره‌وری آب حاکی از آن است که در گروه (A) در دسترس‌بودن آب و در نتیجه افزایش سطح زیر کشت و در گروه (B) جبران کمبود آب و افزایش سطح زیر کشت منجر به افزایش بهره‌وری فیزیکی شده است. در مزارع گروه (A) فروش آب و در مزارع گروه (B) تخصیص آب به محصولات با ارزش اقتصادی بالاتر افزایش بهره‌وری اقتصادی آب را در پی داشته است. به‌طورکلی، می‌توان بیان نمود که تشکیل بازار آب موجب افزایش بهره‌وری می‎گردد، اما تنهایی منجر به‌دستدست‌یابی به کشاورزی پایدار و کاهش مصرف آب در سطح حوضه آبریز نمی‌شود. بنابراین اجرای سیاست‌های دیگر نظیر کنترل برداشت از منابع آب سطحی و زیرزمینی، تحویل حجمی آب براساس الگوی کشت بهینه و تخصیص آب به محصولات با ارزش اقتصادی بالاتر همراه با رویکرد بازار آب می‌تواند علاوه‌ بر کاهش مصرف آب، بهره‌وری آب را نیز ارتقا دهد.

Regie Porras Binayao, Paul Vincent Lagapa Mantua, Holy Rose May Pardillo Namocatcat et al.

This study intends to build smart water irrigation for rice farming using IoT and microcontroller devices with solar panel support. The system demonstrates the capabilities of automated irrigation by reducing physical labor through smart monitoring of the temperature, soil moisture, and humidity using multiple sensors. This study uses an agile methodology as it is suitable for reiterative operation for the development of the prototype. The mean result for the interpretation of data gathered for the systems' adaptability and flexibility is 4.32. The researchers were able to develop smart water irrigation for rice farming using IoT and microcontroller devices with solar panel support and the respondents also agreed that Smart water irrigation for rice farming using IoT and microcontroller devices with solar panel support is practical and valuable. A decision support system is recommended that can analyze data collected from IoT sensors and provide further recommendations. Based on the results, it is also suggested that future researchers use drip irrigation, instead of flood irrigation. Smart water irrigation has the potential to revolutionize agriculture, enhance environmental sustainability, and address pressing global challenges related to water resources and food security. These implications highlight the importance of continued research and innovation in this field.

Adrian Bajraktari, Michelle Binder, Andreas Vogelsang

Modern science is relying on software more than ever. The behavior and outcomes of this software shape the scientific and public discourse on important topics like climate change, economic growth, or the spread of infections. Most researchers creating software for scientific purposes are not trained in Software Engineering. As a consequence, research software is often developed ad hoc without following stringent processes. With this paper, we want to characterize research software as a new application domain that needs attention from the Requirements Engineering community. We conducted an exploratory study based on 8 interviews with 12 researchers who develop software. We describe how researchers elicit, document, and analyze requirements for research software and what processes they follow. From this, we derive specific challenges and describe a vision of Requirements Engineering for research software.

Orestis Lagkas Nikolos, Chloe Alverti, Stratos Psomadakis et al.

Resource elasticity is one of the key defining characteristics of the Function-as-a-Service (FaaS) serverless computing paradigm. While compute resources assigned to VM-sandboxed functions can be seamlessly adjusted on the fly, memory elasticity remains challenging. Hot(un)plugging memory resources suffers from long reclamation latencies and occupies valuable CPU resources. We identify the obliviousness of the OS memory manager to the hotplugged memory as the key issue hindering hot-unplug performance, and design Squeezy, a novel approach for fast and efficient VM memory hot(un)plug, targeting VM-sandboxed serverless functions. Our key insight is that by segregating hotplugged memory regions from regular VM memory, we are able to bound the lifetime of allocations within these regions thus enabling their fast and efficient reclamation. We implement Squeezy in Linux v6.6 as an extension to the OS memory manager. Our evaluation reveals that Squeezy is an order-of-magnitude faster than state-of-the-art, keeping tail latency bounded, when reclaiming VM memory, achieving sub-second reclamation of multiple GiBs of memory while serving realistic FaaS load.

Sh. Shahmansouri, M.R. Mosaddeghi, H. Shariatmadari

IntroductionMonitoring the changes in physical and hydraulic properties and stability of growth media due to root growth effects and wetting and drying cycles is important. Wetting and drying cycles can probably change physical characteristics, availability of water, air and nutrients for the plant and, as a result, might affect the growth and yield of the greenhouse plants. The growth period greatly affects the physical characteristics of the growth substrates; therefore, the watering of growth substrates should be managed according to these changes to avoid improper irrigation.Materials and MethodsIn this study, 14 growth media were prepared from individual substrates with different volumetric ratios. In order to evaluate the changes of growth media over the time (i.e., during consecutive irrigation events) in the greenhouse, 10 wetting and drying cycles were applied on the growth media in the lab. Several physical indicators including easily available water (EAW), air after irrigation (AIR), water buffering capacity (WBC) and water holding capacity (WHC) of the growth media were determined before and after the wetting and drying cycles. Besides, the subsidence, decrease of mass and decomposition of the growth media were determined over the time. Total porosity (TP), bulk density (BD), particle density (PD), pH and electrical conductivity of the mixtures were measured as well.Results and DiscussionThe pH values in the growth media varied from 5.72 to 6.94. The maximum pH value was related to sawdust- sugarcane bagasse biochar produced at 300◦C vermiculite-zeolite, and wheat straw-vermiculite substrates, and the minimum value was related to the cocopeat-perlite substrate. The values of EC in the growth media varied from 0.21 to 1.43 dS m-1. The highest and lowest EC values among the growth substrates were related to date palm bunches-vermiculite-rockwool and rockwool (0.2)-perlite substrates, respectively. The bulk density (BD) values of the growth media varied in the range of 0.163-0.401 Mg m-3. The values ​​of total porosity (TP) of the growth media varied in the range of 64.8-82.8%v/v. The highest TP was related to the cocopeat-perlite substrate. The TP values ​​of most of the substrates were greater than 70%v/v. The average values of EAW in the growth substrates ranged from 0.123 to 0.272 cm3 cm-3. The highest EAW was related to the sawdust-sawdust biochar produced at 500 ◦C vermiculite-zeolite substrate. The application of wetting and drying cycles increased EAW in most of the growth media. Therefore, it can be stated that the time had a positive effect on the EAW in most of the growth media. The average values of AIR before and after the application of wetting and drying cycles for the growth media varied in the range of 0.063-0.240 cm-3 cm3. The highest value of this indicator was observed in the sawdust-date palm bunches biochar produced at 300◦C vermiculite substrate. In all substrates (with the exception of the sawdust-sawdust biochar produced at 500◦C vermiculite-zeolite), the AIR increased after wetting and drying cycles. The range of WHC values before and after applying wetting and drying cycles was 0.453-0.699 cm3 cm-3. The highest WHC belonged to the wheat straw-vermiculite substrate. The WHC values of five growth media, including cocopeat-perlite, decreased due to the application of wetting and drying cycles, and the WHC values of nine growth media decreased. The most stable substrate after the wetting and drying cycles was rockwool-sawdust-vermiculite. The effect of time on the quantity of WBC was positive, so that with the application of wetting and drying cycles, the WBC values of most of the substrates increased. In all substrates, subsidence and dry weight reduction were observed after the wetting and drying cycles. These changes were low for the substrates with a high volumetric ratio of inorganic materials. The least change among the growth substrates in terms of decomposition (dry weight reduction) was related to the completely inorganic substrate rockwool (0.1)-perlite (%0.17). The most stable substrate in terms of subsidence after wetting and drying cycles was the rockwool-sawdust-vermiculite, which has a large volumetric ratio of individual inorganic substrates. The highest subsidence was observed in the substrates containing wheat straw (wheat straw-vermiculite and date palm bunches biochar produced at 300◦C wheat straw-vermiculite). The organic matter content in all the growth substrates decreased over time (after wetting and drying cycles). The decrease of organic matter in the substrates can be related to the decomposition of organic materials as a result of wetting and drying cycles.ConclusionThe BD, TP, EAW and WHC of the majority of growth media were in the optimal ranges and for some mixtures even better than cocopeat-perlite. Wetting and drying cycles could affect the growth media through several processes such as decomposition of organic compounds, displacement and rearrangement of particles, fragmentation of particles, shrinkage, hardening and subsidence. The growth media with a high percent of organic substrates were unstable as compared with those containing a high proportion of inorganic substrates. In general, the wetting and drying cycles increased the frequency of micropores in the growth media. The wetting and drying cycles positively affected EAW, WHC, AIR and WBC of most growth media. These findings imply that wetting and drying cycles may improve the growth media according to the studied extensive variables. However, it is necessary to study the intensive variables such as hydraulic conductivity, oxygen diffusion and pore tortuosity in the growth media for better evaluation of the impact of wetting and drying cycles as well.

DUAN Guoxiu, JIA Xiaoxu, BAI Xiao et al.

【Objective】 Crop growth and ecological functions in arid and semi-arid loess regions in northwestern China are limited not only by topsoil water directly available to crop but by deep soil water which functions as a reservoir. Slopes and lands formed by artificial retaining are two typical geographical units in small watersheds in the loess plateau. This paper presents a method to estimate soil water distribution in them up to 12.5 m deep. 【Method】 The method was based on electrical resistivity tomography (ERT). We measured electrical resistivity of the soil in typical slope and retained land in the small Liudaogou watershed in northern Shaanxi province. Using the measured soil volumetric water content, a power function relating the resistivity to soil water content was established, from which we calculated water distribution and water storage in the 0~12.5 m profile in both the slope and the retained land. 【Result】 The distribution of electrical resistivity over the slope was significantly affected by slope position, with the resistivity decreasing gradually from the slope top to the slope toe. Such changes were associated with vegetation consumption of the topsoil water and redistribution of the infiltrated precipitation over the slope. The vertical distribution of the resistivity in the retained land showed a high-low-high variation; this was also related to root water uptake from the topsoil and precipitation recharge to the subsoil. ERT inversion showed co-existence of a saturated zone and an unsaturated zone in the retained land, while the slope was partly saturated. In a 1.8×104 m2 of retained land, there was 1.49×104 m3 of water in the 0~6.5 m unsaturated layer, and 5.10×104 m3 of water in the saturated layer. In a same area but on the slope, there was only 2.59×104 m3 of water in the 0~12.5 m soil layer. 【Conclusion】 Retained land contains more water than slope, and the deep soil in it functions as a reservoir banking infiltration water in wet seasons. ERT is suitable for measuring spatiotemporal variation in soil moisture in both slopes and flatten plains in the loess plateau.

A.H. Jalali, H. Salemi

IntroductionCumin (Cuminum cyminum L.) is an annual and herbaceous plant, with a vertical, round, narrow and branched stem, with a height of approximately 30-60 cm. This plant belongs to the Apiaceae family. This family is known for having plants with aromatic taste. Iran and some countries along the Mediterranean Sea are known as the primary origin for the cumin plant. In addition to Iran, cumin is cultivated in many countries such as Uzbekistan, Tajikistan, Turkey, Morocco, India, Syria, Mexico and Chile. About 300,000 tons of cumin seeds are produced in the world annually, of which China and Asian countries produce 70% and consume 90%. Short growing season (100 to 120 days), low water requirement and the possibility of rained cultivation, non-interference between cultivation and harvesting with other crops and no price fluctuation and proper economic justification are among the factors that interest farmers in cultivating this plant. In different regions, yields of 350 to more than 1000 kg of seeds are obtained from this plant, and 3350 cubic meters of pure water are needed for production. Materials and MethodsThis research was conducted in 2015 to 2017. The first year of the study included the collection and analysis of long-term climatic data of the region, and the second year included the implementation phase of the research. Analyzing meteorological data on the scale of decades and the cases of temperature, precipitation, wind speed, sunshine hours, relative humidity and evaporation from the pan were considered as criteria and by preparing the gradient equations, the rate of reference evaporation and transpiration was calculated. The required statistical information was obtained from 28 synoptic meteorological and climatology stations in Isfahan and some neighboring provinces. In the studies related to soil, apparent specific gravity and volumetric moisture content (field capacity and wilting point), soil salinity, soil texture and agricultural ability class of land in cultivation areas were considered. Soil-related information was used to calculate the soil evaporation coefficient (Ke), which describes the evaporation component in the trait (ETc). In fact, Ke is the basis for calculating the coefficient of reduction of evaporation from the surface layer (Kr) and the fraction of soil wet and exposed to air (few), and for its calculation, the presence of information related to soil characteristics is necessary. To calculate the soil characteristics, in addition to sampling from the fields in the research, the database of 1600 soil profiles in the soil and water research department of Isfahan province was also used. Results and DiscussionThe results showed that 18 cities in Isfahan province had cumin cultivation potential, which had a significant difference in terms of pure water requirement per hectare (5% level) and water consumption at different phenological stages (1% statistical level). In terms of water requirement per hectare, the cities of Isfahan province can be divided into three groups. Average water requirement per hectare in the first group (the cities of Golpayegan, Lenjan, Tiran and Karvan, Shahin and Shahr and Mime), the second group (the cities of Isfahan, Khomeini Shahr, Falavarjan, Shahreza, Kashan, Najaf Abad, Natanz), Mobarake, Dehaghan and Borkhar), and the third group (Aran and Bidgol, Ardestan, Khoor and Biabanak and Nain) were equal to 3000, 3240 and 3770 m-3 ha-1, respectively. The water requirement of the growth development stage in the cities of the third group was equal to 2029 m-3 ha-1, which was significantly different from the cities of the first and second groups (p < 1% level). According to the results, cumin might be a suitable plant for crop rotations in Isfahan province due to its low water requirement and tolerance to moisture stress. ConclusionThe water requirement for cultivating cumin in various regions of the province is notably lower compared to many common crops, such as wheat, barley, and safflower. In 10 out of the 18 cities included in the study, significant water savings of up to 3,240 cubic meters per hectare can be achieved by optimizing water transfer efficiency. For cumin cultivation, this water conservation can even reach 3,000 cubic meters in cities with cooler climates. Surprisingly, in the hot areas of Isfahan province, including Ardestan, Nain, Khoor, Biabanak, Aran, and Bidgol, it is feasible to grow cumin with a water consumption of just 3,770 cubic meters per hectare.

M. Babaei, M.T. Sattari

IntroductionDevelopment of reservoirs helps to meet food and energy needs by supplying water for agriculture and hydropower plants. Efficient management of water resources is important and vital to overcome the problems of water leakage and meet agricultural, industrial and drinking needs. Each of these requirements creates limitations in the way the reservoir is operated, which requires accurate information on the changes in the reservoir storage and other influential components during the operation period. In order to manage and plan water resources at country scale, using reservoir simulation models as a suitable tool in simulating processes related to dams, such as the operation of water reservoirs, will be very effective. Reservoir simulation models such as the HEC-ResSim model provide the opportunity to simulate the natural and hydrological processes related to the water resources system and the relationships between the supply and demand sectors by implementing a schematic structure of a real reservoir. Two scenarios of water savings of 20 and 30 percent were used in the current investigation.  Additionally, using this method, the objectives of water resource management can be assessed.Materials and MethodsIn the present study, the use of the Latian reservoir in real conditions was simulated using the HEC-ResSim model. The simulation was carried out according to the river's inflow from 1968 to 2018, downstream water needs, energy production capacity by turbines, physical characteristics and reservoir building. The implementation of the HEC-ResSim model is summarized in three steps. The Watershed Setup module is used to introduce the general outline of the watershed. In this module, the shape and geographical location of the basin and related elements such as rivers, reservoirs, hydrometric stations and other projects in it should be specified. The Reservoir Network module is used to introduce the desired reservoir network and to enter the physical characteristics and how to use them. The Simulation module is designed to introduce the simulation period and display the model outputs.  In this module, the simulation time and period and the operation pattern should be determined.Results and DiscussionAccording to the results obtained from the reservoir simulation model, the average storage capacity of Latian dam for the simulation period was estimated to be 41 million cubic meters, which shows a significant drop of 49% compared to the normal level (83 million cubic meters). Additionally, for the same period, it was estimated that the average discharge was equivalent to 5.4 cubic meters per second and the average inflow to the reservoir of the Latian dam was equal to 5.7 cubic meters per second. This is in contrast to the period's average demand, which for the area downstream of the Latian Dam is 12.1 cubic meters. The findings indicate that the reservoir of the dam frequently, and particularly at the conclusion of the simulation period, is unable to satisfy the needs of the downstream. Additionally, according to the findings of the current study, the Latian dam power plant's (Kalan) average annual hydro-electric energy production was projected to be 68,000 MWh, and the results show that in accordance with the policy of operating the Latian dam in the majority ofthe years, the Kalan power plant is able to supply the electricity required in the study area. According to the results, the average reservoir volume of Latian dam for the entire period in the first and second scenario was estimated to be 49 and 63 million cubic meters, respectively. Also, by applying the first and second water saving scenarios, the Latian dam reservoir will be able to generate 66,000 and 63,000 MWh of energy annually.ConclusionIn this study, the functioning and operation of the Latian dam reservoir was used by applying the Hec-ResSim reservoir simulation model. After entering data such as the elevation and length of the dam, surface-volume-elevation curve, evaporation from the surface of the reservoir, elevation and uncontrolled outlet coefficient, dam storage areas, rule curve, were simulated by the model. In the present study, the values of inactive volume and conservation volume of Latian Dam were estimated as 28 and 83 million cubic meters, respectively. The average water release of Latian dam for the first and second 25 years of operation was equal to 6.1 and 3.7 cubic meters per second, respectively, which met 50 and 32% of the downstream demand on average. The results indicate that the success rate of Latian dam in supplying drinking, industry and downstream environment for the period of operation is 42%. Also, 16 years out of 50 years of operation, Kalan hydropower plant has fully met 100% of the needs. On average, the large power plant is able to provide 80% of the energy needs of the study area for the entire simulation period.

Xianzhong Ding, Wan Du

Agricultural irrigation is a significant contributor to freshwater consumption. However, the current irrigation systems used in the field are not efficient. They rely mainly on soil moisture sensors and the experience of growers, but do not account for future soil moisture loss. Predicting soil moisture loss is challenging because it is influenced by numerous factors, including soil texture, weather conditions, and plant characteristics. This paper proposes a solution to improve irrigation efficiency, which is called DRLIC. DRLIC is a sophisticated irrigation system that uses deep reinforcement learning (DRL) to optimize its performance. The system employs a neural network, known as the DRL control agent, which learns an optimal control policy that considers both the current soil moisture measurement and the future soil moisture loss. We introduce an irrigation reward function that enables our control agent to learn from previous experiences. However, there may be instances where the output of our DRL control agent is unsafe, such as irrigating too much or too little water. To avoid damaging the health of the plants, we implement a safety mechanism that employs a soil moisture predictor to estimate the performance of each action. If the predicted outcome is deemed unsafe, we perform a relatively-conservative action instead. To demonstrate the real-world application of our approach, we developed an irrigation system that comprises sprinklers, sensing and control nodes, and a wireless network. We evaluate the performance of DRLIC by deploying it in a testbed consisting of six almond trees. During a 15-day in-field experiment, we compared the water consumption of DRLIC with a widely-used irrigation scheme. Our results indicate that DRLIC outperformed the traditional irrigation method by achieving a water savings of up to 9.52%.

Jan Heine, Herbert Palm

The increasing pressure within VUCA (volatility, uncertainty, complexity and ambiguity) driven environments causes traditional, plan-driven Systems Engineering approaches to no longer suffice. Agility is then changing from a "nice-to-have" to a "must-have" capability for successful system developing organisations. The current state of the art, however, does not provide clear answers on how to map this need in terms of processes, methods, tools and competencies (PMTC) and how to successfully manage the transition within established industries. In this paper, we propose an agile Systems Engineering (SE) Framework for the automotive industry to meet the new agility demand. In addition to the methodological background, we present results of a pilot project in the chassis development department of a German automotive manufacturer and demonstrate the effectiveness of the newly proposed framework. By adopting the described agile SE Framework, companies can foster innovation and collaboration based on a learning, continuous improvement and self-reinforcing base.

Muhammad Zubair Khan, Oleg E. Peil, Apoorva Sharma et al.

In the rapidly expanding field of two-dimensional materials, magnetic monolayers show great promise for the future applications in nanoelectronics, data storage, and sensing. The research in intrinsically magnetic two-dimensional materials mainly focuses on synthetic iodide and telluride based compounds, which inherently suffer from the lack of ambient stability. So far, naturally occurring layered magnetic materials have been vastly overlooked. These minerals offer a unique opportunity to explore air-stable complex layered systems with high concentration of local moment bearing ions. We demonstrate magnetic ordering in iron-rich two-dimensional phyllosilicates, focusing on mineral species of minnesotaite, annite, and biotite. These are naturally occurring van der Waals magnetic materials which integrate local moment baring ions of iron via magnesium/aluminium substitution in their octahedral sites. Due to self-inherent capping by silicate/aluminate tetrahedral groups, ultra-thin layers are air-stable. Chemical characterization, quantitative elemental analysis, and iron oxidation states were determined via Raman spectroscopy, wavelength disperse X-ray spectroscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. Superconducting quantum interference device magnetometry measurements were performed to examine the magnetic ordering. These layered materials exhibit paramagnetic or superparamagnetic characteristics at room temperature. At low temperature ferrimagnetic or antiferromagnetic ordering occurs, with the critical ordering temperature of 38.7 K for minnesotaite, 36.1 K for annite, and 4.9 K for biotite. In-field magnetic force microscopy on iron bearing phyllosilicates confirmed the paramagnetic response at room temperature, present down to monolayers.

XUE Ping, LIU Ling, WANG Yangren et al.

【Objective】 The Jensen formula is a nonlinear model for calculating the response of crop yield to water and nutrient applications. It contains a number of parameters which need calibration against experimental data. The aim of this paper is to present a method to inversely estimate these parameters using experimental data. 【Method】 The method is based on the tuna swarm optimization algorithm (TSO). A distribution estimation (ITSO) was used to form the tuna swarm optimization algorithm (TSO), and the performance of the proposed tuna swarm optimization algorithm was verified against other algorithms based on the CEC2017 test. The accuracy and efficiency of the method were compared with other methods based on experimental data obtained from the Xiaohe Irrigation Experimental Station in Shanxi province. 【Result】 Comparing the performance of ITSO, TSO, GWO, WOA, SSA and BOA methods shows that the proposed algorithm is the best. Comparing ITSO with the nonlinear regression analysis in the SPSS software and TSO shows that the relative error of the proposed method is 7.79%, 8.13% and 7.79%, respectively. The TSO algorithm converged in 50 iterations, while the ITSO algorithm found the optimal solution in just 35 iterations. 【Conclusion】 The tuna swarm optimization algorithm combined with the distribution estimation (ITSO) is efficient for estimating the parameters in the Jensen model. It is highly accurate and converges fast.

WANG Kun, CHEN Lin, PANG Danbo et al.

【Objective】 Precipitation and evapotranspiration are two important parameters required in hydrological modelling and water resource management. In this paper, we analyzed their temporal variation in the arid area in central Ningxia province. 【Method】 The analysis was based on precipitation and monthly average temperature measured from 1969 to 2020 from six meteorological stations across the area. Spatiotemporal variation in the precipitation and net precipitation (the difference between precipitation and evapotranspiration) was calculated using the Koichiro Takahashi's evapotranspiration formula, climate trend method, Mann-Kendall mutation test and the wavelet cycle analysis. 【Result】 ① The precipitation in northwest and southeast of the area differed considerably, with the precipitation in the former and the latter being 188.0 mm and 304.1 mm, and their associated net precipitation being 17.8 mm and 58.9 mm, respectively. ② Rainfall in the area falls mainly in summer, accounting for 57% of the annual precipitation, while precipitation in the winter is the least, accounting for only 3% of annual precipitation. The net precipitation in spring and winter is lower than that in other seasons. ③ Interannual variation in net precipitation has been in a transition from fluctuations to continued drying in the studied period. The extreme rainfalls were mainly in the southeast, and the net precipitation in the northwest was more abundant before 2013 than after 2013. ④ Trend analysis shows that the annual precipitation and net precipitation in the southeast have increased significantly at 1.539 mm/a and 0.467 mm/a, respectively. In contrast, the precipitation in the northwest had increased at 0.647 mm/a, while the net precipitation had been decreasing at 0.073 mm/a though not at a significant level. Mutation analysis showed an abrupt precipitation change in 2010. ⑤ Precipitation and net precipitation in the studied area showed periodicities of 9, 12~13, 40 a, with their associated oscillating periods being 6, 9 and 25 a, respectively. The net precipitation varied largely, having a greater impact on agriculture and animal husbandry. 【Conclusion】 Precipitation and net precipitation in the southeast is more abundant than in the northwest of the studied area. The magnitude of seasonal annual precipitation and net precipitation are ranked in the order of summer>autumn>spring>winter. Precipitation and net precipitation in the studied area have been increasing over the studied period.

YUAN Jingjing, QI Xuebin, ZHAO Jing et al.

【Background and objective】 Biogas slurry and biochar have been increasingly used to amend soils for different purposes ranging from as soil conditioner to fertilizer. While their influence on soil properties has been well documented, their impact on soil aggregation and the consequence for soil organic distribution was poorly understood. The purpose of this paper is to fill this knowledge gap. 【Method】 The experiment was conducted in the field with no biochar amendment taken as the control (CK). For each biochar amendment (B), there were three slurry (originated from pig manure) applications at volumetric ratios (water∶slurry): 1∶6 (BS1), 1∶4 (BS2) and 1∶2 (BS3), respectively. Soil samples were taken from each treatment at the end of the experiment, and the proportions of aggregates of different sizes in the range of >5 mm, 2~5, 1~2, 0.25~1 mm and <0.25 mm were determined by wet sieving method. Organic carbon in each group of aggregates was measured using standard method. 【Result】 Amending the soil with biochar in combination with biogas slurry irrigation improved the proportion of >0.25 mm aggregates significantly by 13.0%～36.3%, compared with the CK. The mean weight diameter (MWD) and geometric diameter (GMD) of the aggregates in all treatments were both higher than that in the CK, increasing by 9.8%～39.3% (MWD) and 10.0%～37.5% (GMD), respectively. Both MWD and GMD peaked when the slurry application was 1∶4. All treatments also increased soil organic carbon in aggregates of different sizes significantly, beneficial to soil quality. Significant positive correlations were found among organic carbon content in different aggregates, macro-aggregates (>0.25 mm), MWD and GMD (P<0.01). The treatments reduced soil bulk density significantly, with the highest decrease being 6.7% in B+BS3. All these showed that applying biochar and pig manure biogas slurry to soil has a significantly positive effect on soil aggregation, improving soil structure and carbon sequestration. 【Conclusion】 Biochar amendment and biogas slurry irrigation improved soil quality. For all treatments we compared, the optimal application of biochar and the slurry was 12 t/hm2 and 1∶4, respectively.

Shaiban Ahmed, David Le, Taeyoon Son et al.

Chromatic dispersion is a common problem to degrade the system resolution in optical coherence tomography (OCT). This study is to develop a deep learning network for automated dispersion compensation (ADC-Net) in OCT. The ADC-Net is based on a redesigned UNet architecture which employs an encoder-decoder pipeline. The input section encompasses partially compensated OCT B-scans with individual retinal layers optimized. Corresponding output is a fully compensated OCT B-scans with all retinal layers optimized. Two numeric parameters, i.e., peak signal to noise ratio (PSNR) and structural similarity index metric computed at multiple scales (MS-SSIM), were used for objective assessment of the ADC-Net performance. Comparative analysis of training models, including single, three, five, seven and nine input channels were implemented. The five-input channels implementation was observed as the optimal mode for ADC-Net training to achieve robust dispersion compensation in OCT

F. Cigna, D. Tapete

This work provides Synthetic Aperture Radar (SAR) big data investigations based on ESA's Geohazards Exploitation Platform (GEP) and the Parallel Small BAseline Subset (P-SBAS) Interferometric SAR (InSAR) on-demand service. Six Sentinel-1 IW SAR stacks for a total of 981 scenes acquired in 2014–2020 were processed to generate advanced ground deformation products providing key geo-information on natural and anthropogenic processes affecting 4 study areas in the Mediterranean: Tunis (Tunisia), the town of Gela (Italy), Methana volcano (Greece), and Crotone and the Capo Colonna promontory (Italy). The identified geohazards comprise subsidence due to land drainage, reclamation and compaction, soil consolidation and infrastructure settlement following engineering works, groundwater pumping for irrigation and industrial use, hydrocarbon extraction, slow-moving landslides and erosion landforms.