Top-view Area Research Articles

Experimental study on the stable and dynamic characteristics during silicone oil spreading process on saline water sublayer with different salinities under various temperature conditions

This study investigated the influence of salinity on the spreading behavior of oil at varying temperatures on a calm sea surface through a series of experiments involving the spreading of silicone oil on saline water sublayers with salinities of 0, 5, 10, and 20 ppt (parts per thousand, equivalent to 1‰) across a range of temperatures from 5 to 35 °C. Real-time observations were made of the oil's morphology from both top and side perspectives. The top-view area of the oil slick was not only recorded, but also the side-view morphology of the oil slick was tracked and photographed during the whole process, and the dynamic process of the angle and thickness was measured. The results indicate that higher temperatures and salinity levels increase spreading area. The stable angle was determined by considering three-phase surface tension and Neumann’s rule. The stabilized thickness based on the angle is derived by combining capillary pressure analysis and the Young-Laplace equation. A dynamic thickness model was developed based on force analysis, primarily relying on differential pressure force and surface tension. This study offers valuable theoretical insights to aid in predicting the oil spread thickness of oil spills in various sea regions.

Modelling of demolition waste generation: Application to Greek residential buildings.

The construction sector in Europe is among the biggest waste generators, producing 370 million tonnes of construction and demolition waste (CDW) every year, which contain important secondary materials. Quantification of CDW is important from their circular management and environmental impact point of view. Thus, the overall objective of this study was to develop a modelling methodology for estimating demolition waste (DW) generation. The volumes (m3) of individual construction materials contained in 45 residential buildings in Greece were accurately estimated using computer-aided design (CAD) software and the materials were classified according to European List of Waste. These materials will become waste upon demolition, with a total estimated generation rate of 1590 kg m-2 of top view area and with concrete and bricks representing 74.5% of total. Linear regression models were developed to predict the total and individual amounts of 12 different building materials based on structural building characteristics. To test the accuracy of the models, the materials of two residential buildings were quantified and classified and the results were compared with the model predictions. Depending on the model used, the % differences between models' predictions and CAD estimates for total DW averaged 11.1% ± 7.4% for the first case study and 2.5% ± 1.5% for the second. The models can be used for accurate quantification of total and individual DW and their management within the framework of circular economy.

A New Design of the 3D Deployable Solar Array in the Aerospace Field and Kinematic Analysis during Deployment

The paper focuses on a new design of the 3D deployable solar array for spacecraft and landers. Compared with existing solar array designs, the main advantage of this new design is the further increase in the area of the solar array. The principles of spatial rings and domes are used for this new design. This design consists of a large dome and four smaller rings. The model is constructed using Solidworks, and different configurations during the deployment are shown. The kinematic analysis shows that the length ratios of elements are independent of the input angle θ. It proves that this deployable structure has only one mobility. The configuration can be determined by a specific input angle. When the input angle θ increases, the top-view area of the structure increases, while the maximum height of the structure decreases. The volume of the increases and then decreases with the increasing θ. The maximum volume occurs at θ = 110°. In addition, the shape of the top-view geometry for a particular design is determined by two design parameters. It is found that the length ratios of elements increase with the increasing value of two design parameters.

Multi-trait association study identifies loci associated with tolerance of low phosphorus in Oryza sativa and its wild relatives

We studied variation in adaptive traits and genetic association to understand the low P responses, including the symbiotic association of arbuscular mycorrhizal (AM) fungal colonization in Oryza species (O. sativa, O. nivara, and O. rufipogon). In the present experiment, we performed the phenotypic variability of the morphometric and geometric traits for P deficiency tolerance and conducted the association studies in GLM and MLM methods. A positive association between the geometric trait of the top-view area and root traits suggested the possibility of exploring a non-destructive approach in screening genotypes under low P. The AMOVA revealed a higher proportion of variation among the individuals as they belonged to different species of Oryza and the NM value was 2.0, indicating possible gene flow between populations. A sub-cluster with superior-performing accessions had a higher proportion of landraces (42.85%), and O. rufipogon (33.3%) was differentiated by four Pup1-specific markers. Association mapping identified seven notable markers (RM259, RM297, RM30, RM6966, RM242, RM184, and PAP1) and six potential genotypes (IC459373, Chakhao Aumbi, AC100219, AC100062, Sekri, and Kumbhi Phou), which will be helpful in the marker-assisted breeding to improve rice for P-deprived condition. In addition, total root surface area becomes a single major trait that helps in P uptake under deficit P up to 33% than mycorrhizal colonization. Further, the phenotypic analysis of the morphometric and geometric trait variations and their interactions provides excellent potential for selecting donors for improving P-use efficiency. The identified potential candidate genes and markers offered new insights into our understanding of the molecular and physiological mechanisms driving PUE and improving grain yield under low-P conditions.

Estimation of Grapevine Crop Coefficient Using a Multispectral Camera on an Unmanned Aerial Vehicle

Crop water status and irrigation requirements are of great importance to the horticultural industry due to changing climatic conditions leading to high evaporative demands, drought and water scarcity in semi-arid and arid regions worldwide. Irrigation scheduling strategies based on evapotranspiration (ET), such as regulated deficit irrigation, requires the estimation of seasonal crop coefficients (kc). The ET-driven irrigation decisions for grapevines rely on the sampling of several kc values from each irrigation zone. Here, we present an unmanned aerial vehicle (UAV)-based technique to estimate kc at the single vine level in order to capture the spatial variability of water requirements in a commercial vineyard located in South Australia. A UAV carrying a multispectral sensor is used to extract the spectral, as well as the structural, information of Cabernet Sauvignon grapevines. The spectral and structural information, acquired at the various phenological stages of the vine through two seasons, is used to model kc using univariate (simple linear), multivariate (generalised linear and additive) and machine learning (convolution neural network and random forest) model frameworks. The structural information (e.g., canopy top view area) had the strongest correlation with kc throughout the season (p ≤ 0.001; Pearson R = 0.56), while the spectral indices (e.g., normalised indices) turned less-sensitive post véraison—the onset of ripening in grapes. Combining structural and spectral information improved the model’s performance. Among the investigated predictive models, the random forest predicted kc with the highest accuracy (R2: 0.675, root mean square error: 0.062, and mean absolute error: 0.047). This UAV-based approach improves the precision of irrigation by capturing the spatial variability of kc within a vineyard. Combined with an energy balance model, the water needs of a vineyard can be computed on a weekly or sub-weekly basis for precision irrigation. The UAV-based characterisation of kc can further enhance the water management and irrigation zoning by matching the infrastructure with the spatial variability of the irrigation demand.

Non-destructive phenotyping for early seedling vigor in direct-seeded rice

BackgroundEarly seedling vigor is an essential trait of direct-seeded rice. It helps the seedlings to compete with weeds for water and nutrient availability, and contributes to better seedling establishment during the initial phase of crop growth. Seedling vigor is a complex trait, and phenotyping by a destructive method limits the improvement of this trait through traditional breeding. Hence, a non-invasive, rapid, and precise image-based phenotyping technique is developed to increase the possibility to improve early seedling vigor through breeding in rice and other field crops.ResultsTo establish and assess the methodology using free-source software, early seedling vigor was estimated from images captured with a digital SLR camera in a non-destructive way. Here, the legitimacy and strength of the method have been proved through screening seven diverse rice cultivars varying for early seedling vigor. In the regression analysis, whole-plant area (WPA) estimated by destructive-flatbed scanner (WPAs) and non-destructive imaging (WPAi) approaches was strongly related (R2 > 83%) and suggested that WPAi can be adapted in place of destructive methods to estimate seedling vigor. In addition, this study has identified a set of new geometric traits (convex hull and top view area) for screening breeding lines for early seedling vigor in rice, which decreased the time by 80% and halved the cost of labor in data observation.ConclusionsThe method demonstrated here is affordable and easy to establish as a phenotypic platform. It is suitable for most glasshouses/net houses for characterizing genotypes to understand the plasticity of shoots under a given environment at the seedling stage. The methodology explained in this experiment has been proven to be practical and suggested as a technique for researchers involved in direct-seeded rice. Consequently, it will help in the simultaneous screening of genotypes in large numbers, the identification of donors, and in gaining information on the genetic basis of the trait to design a breeding program for direct-seeded rice.

A Robust Automated Image-Based Phenotyping Method for Rapid Vegetative Screening of Wheat Germplasm for Nitrogen Use Efficiency.

Nitrogen use efficiency (NUE) in crops is generally low, with more than 60% of applied nitrogen (N) being lost to the environment, which increases production costs and affects ecosystems and human habitats. To overcome these issues, the breeding of crop varieties with improved NUE is needed, requiring efficient phenotyping methods along with molecular and genetic approaches. To develop an effective phenotypic screening method, experiments on wheat varieties under various N levels were conducted in the automated phenotyping platform at Plant Phenomics Victoria, Horsham. The results from the initial experiment showed that two relative N levels—5 mM and 20 mM, designated as low and optimum N, respectively—were ideal to screen a diverse range of wheat germplasm for NUE on the automated imaging phenotyping platform. In the second experiment, estimated plant parameters such as shoot biomass and top-view area, derived from digital images, showed high correlations with phenotypic traits such as shoot biomass and leaf area seven weeks after sowing, indicating that they could be used as surrogate measures of the latter. Plant growth analysis confirmed that the estimated plant parameters from the vegetative linear growth phase determined by the “broken-stick” model could effectively differentiate the performance of wheat varieties for NUE. Based on this study, vegetative phenotypic screens should focus on selecting wheat varieties under low N conditions, which were highly correlated with biomass and grain yield at harvest. Analysis indicated a relationship between controlled and field conditions for the same varieties, suggesting that greenhouse screens could be used to prioritise a higher value germplasm for subsequent field studies. Overall, our results showed that this phenotypic screening method is highly applicable and can be applied for the identification of N-efficient wheat germplasm at the vegetative growth phase.

Automated phenotyping for early vigour of field pea seedlings in controlled environment by colour imaging technology.

Early vigour of seedlings is a beneficial trait of field pea (Pisum sativum L.) that contributes to weed control, water use efficiency and is likely to contribute to yield under certain environments. Although breeding is considered the most effective approach to improve early vigour of field pea, the absence of a robust and high-throughput phenotyping tool to dissect this complex trait is currently a major obstacle of genetic improvement programs to address this issue. To develop this tool, separate trials on 44 genetically diverse field pea genotypes were conducted in the automated plant phenotyping platform of Plant Phenomics Victoria, Horsham and in the field, respectively. High correlation between estimated plant parameters derived from the automated phenotyping platform and important early vigour traits such as shoot biomass, leaf area and plant height indicated that the derived plant parameters can be used to predict vigour traits in field pea seedlings. Plant growth analysis demonstrated that the “broken-stick” model fitted well with the growth pattern of all field pea genotypes and can be used to determine the linear growth phase. Further analysis suggested that the estimated plant parameters collected at the linear growth phase can effectively differentiate early vigour across field pea genotypes. High correlation between normalised difference vegetation indices captured from the field trial and estimated shoot biomass and top-view area confirmed the consistent performance of early vigour field pea genotypes under controlled and field environments. Overall, our results demonstrated that this robust screening tool is highly applicable and will enable breeding programs to rapidly identify early vigour traits and utilise germplasm to contribute to the genetic improvement of field peas.

Two dynamic energy budget models for the harpacticoid copepod Nitocra spinipes

The harpacticoid copepod Nitocra spinipes is a commonly used test species in ecotoxicological studies and subject of multiple international testing guidelines. While we strive for a better understanding of toxicant-induced effects in this species, physiological models rooted in the Dynamic Energy Budget (DEB) theory can help to explain such effects on the level of energy allocations within the organism. In previous works that aimed to capture the copepod life history in a DEB model, diverging assumptions on the growth pattern of copepods were made. While some authors presumed von Bertalanffy growth, others presumed an upcurving in length versus time due to metabolic acceleration. In this study we parametrized the two typified DEB models “abp” (metabolic acceleration from birth to puberty) and “sbp” (standard von Bertalanffy growth from birth to puberty) on life history data of N. spinipes. Besides using data from literature, we also measured additional length-at-time data to aid the parameter estimation. As the body proportions of N. spinipes changed continuously throughout its development, we used the square root of the top view area as a length measure to scale with the cube root of structural volume in length-to-volume conversions. Experimental data were predicted well with both models according to goodness of fit criteria. Despite a slightly better data fit in abp, we cannot rule out sbp as implausible. Overall, we expect both models to perform equally well in future applications. More detailed data on N. spinipes and closely related species are needed to support or reject the presumption of metabolic acceleration in the life history of copepods.

Effect of Light Illumination on Leaves Movement of <i>Mimosa pudica</i>

A study on the effect of light illumination introduced to the leaves of Mimosa pudica was carried out using different light intensities. The leaves will open gradually from the closed condition after the light was illuminated. Plant of M. pudica was placed in the dark box during measurement meanwhile the Petiole (part of the stem) of the plant was at normal position (hanging up). The camera was fixed to the box to monitor the leaves’ movement continuous and real time. By using this method the change of the top view area of the leaves could be observed. A crossed line was drawn on the image recorded and was measured its length. The calculation of the length gives the percentage of leaves at open during the observation time. Ultrasonic apparatus was also used to monitor the change of leaves. From the results, at an illumination intensity of 200 Lux, the percentage of leaves to open completely with respects to the observation time was found to increase nonlinearly by taking the time of 25 minutes. For intensities of 400 Lux, the trend of curve was also similar but increase rapidly. The ultrasonic signals show much stable at 200 Lux comparing to 400 Lux that was fluctuating. That may be due to the relatively faster movement of the leaves to open. This natural phenomenon is interesting and may introduce any change of natural indication that could be explored for further applications.

Estimation of Whole Volume of Green Shelled Mussels using their Geometrical Attributes Obtained from Image Analysis

Aquacultured green shelled mussels are an important export product of New Zealand. Using image analysis, several geometrical attributes of live mussels were measured. The volume of individual live mussels was estimated by several methods. When the cubic splines method was applied to top and side view images, volume was estimated with a coefficient of determination of R2 = 0.97. When only the top view area was used, the R2 decreased to 0.94. When the side view area was also included and empirical equations were fitted to estimate whole volume, the R2 was 0.97. When measured length, width, and thickness were used to estimate volume, the R2 was 0.95. There was a wide variation of the measured density of live mussels (1.05–1.27 g/cm3). Also, the condition index of the live mussels varied between 48 and 95. There was no correlation between the size of the mussel and its condition index. The mass of the mussel meat could not be accurately predicted by using the whole mass of the live mussel.

Sediment yield from irregularly shaped gullies located on the Fortuna lithologic formation in semi-arid area of Tunisia

The Fortuna geological formation dated from the late Oligocene to early Miocene is mainly composed of friable sandstone. Gully erosion on this substratum is developing complex shaped gullies where bank processes are as important as head advance by cutting and bed deepening by vertical incision. For irregularly shaped gullies quantitative information on gully erosion rates as related to gully head extension are scarce because bank active sides take many forms presumably depending on topography, climate and lithology. Our field cross section measurements of 4 gullies developed in the Fortuna Formation, (2 located on a steep slope area (> 15%) and the other two on a gentle slope (< 9%)), have shown that the geometry of these gullies is far from a conical gully shape. These field measurements were used to calculate gully reaches geometry and volume variation. No direct relationships between gully volume and length could be established for these gullies in the Fortuna formation. Nevertheless, since both gully top view area and maximum top width are increasing, as the gully reach length increases, relationships could be established between maximum top width and their equivalent width defined as the ratio between gully reach top view area and its length. Then, gully volume–length relationships could be established for each of the 5 maximum bank-full widths studied on the two gentle and two steep slope gullies. For any maximum top width, the gully volume–length relationship was found to be not unique but the volume is increasing linearly up to the 15 m and 45 m distance from the gully head and then logarithmically for steep and gentle slope gullies, respectively. The linear and logarithmic equations' coefficients were also found to be a function of gully maximum top width. These equations were then used to quantify gully sediment yields related to gully shape evolution for eight gullies tributaries of As Sahsafa wadis. For this purpose the top view areas and lengths of these eight gullies were digitized and monitored on rectified air photographs of 1962, 1974 and 2000 using a Geographic Information System (Arc View). Half of these gullies were located in an area with a gentle slope gradient and the other half with steep slope gradient. The average gullies length variation for the whole study period (1962–2000) were 11.74% and 10.32% whereas the average top view areas variation was 23.57% and 29.4% for gentle and steep slope gullies, respectively. Gullies volume changes during the periods 1962–1974 and 1974–2000 were then derived from the variation of gullies length and top view areas photo-measurements on these 8 tributaries using the relationships established from the four measured gullies. On gentle slopes, the average gully sediment yields during 1962–1974 and 1974–2000 periods were 3.98 and 2.28 m3 ha− 1 year− 1, respectively. On steep slopes, these values are 4.82 and 2.47 m3 ha− 1 year− 1.

Application of Image Processing to Analyze Shrinkage and Shape Changes of Shrimp Batch during Drying

In this article, variations in the top-view area and lateral-view area, average area, perimeter, Feret diameter, roundness, elongation, shape of the edge, and diameters of the shrimp in the batch parallel and perpendicular to the drying medium flow were investigated in defined intervals during drying. For this purpose, a thin-layer dryer based on machine vision was fabricated and image analysis techniques were used. Drying experiments were conducted in triplicate at five drying temperatures of 50, 70, 90, 110, and 120°C and three drying medium velocities of 1, 1.5, and 2 m/s. Purely near-atmospheric superheated steam drying (SSD) was used for the temperatures above the boiling point of water (110 and 120°C). Drying at the other temperatures was done using a hot air convective method. Analysis of batch area shrinkage, average area shrinkage, normalized Feret diameter, dimensionless perimeter, and diameters parallel and perpendicular to the drying medium flow showed that there are almost linear relations with moisture content. Drying medium temperature and velocity had a significant effect on all measured morphological parameters (P < 0.01). There was a significant difference between shrinkage of diameters parallel and perpendicular to the drying medium flow in all studied drying conditions, which implies that shrinkage of shrimp samples was nonisotropic. Moreover, comparing the top- and lateral-view areas of the shrimp batch showed that there was nonisotropic shrinkage in the shrimp samples during drying process. More regular and irregular edges of shrimp were obtained at low and high temperatures, respectively. Drying took place entirely in the falling rate period. Drying medium velocity had no significant effect on drying time. No regular trend regarding the effect of the studied drying medium velocities on the roundness and elongation of shrimp samples was found. More porous shrimp samples with a lower degree of shrinkage were obtained in superheated steam drying in comparison to hot air drying at high temperatures.

Flow boiling in constructal tree-shaped minichannel network

Flow boiling in constructal tree-shaped minichannel network with an inlet diameter of 4 mm is numerically investigated using a one-dimensional model, taking into consideration the minor losses at junctions. The pumping power requirement, pressure drop, temperature uniformity and coefficient of performance of the constructal tree-shaped minichannel network are all evaluated and compared with those of the corresponding traditional serpentine channel, and the fluid stream undergoes a phase change from saturated liquid to saturated vapor. The effects of the length dimension and top view area (i.e. the path length) on saturated gas–liquid two-phase flow boiling heat transfer in tree-shaped minichannel networks are all analyzed and discussed. The results indicated that, the tree-shaped network configured with length dimension of two is able to maximum flow access; the path length plays a significant role in the determination of flow boiling in tree-shaped minichannel networks. In particular, compared to the traditional serpentine channel, flow boiling in constructal tree-shaped minichannnel network possesses less pressure drop, lower pumping power requirement, better temperature uniformity and higher coefficient of performance ( COP).