Biosynthesis of silver nanoparticles was achieved by novel simple green chemistry procedure using Achyranthes aspera leaf extract as a reducing and a capping agent. The present study focuses on larvicidal activity of synthesized silver nanoparticles (AgNPs) against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi. Range of concentrations of synthesized AgNPs (2, 4, 6, 8 and 10 mg/ml) and the aqueous extract (100, 50, 25, 12.5 and 6.25 mg/ml) were tested against the fourth instar larvae for 24 h exposure. The maximum efficacy was observed in the synthesized AgNPs against Cx. quinquefasciatus (LC₅₀ 2.48; LC₉₀ 8.14 mg/ml) and Ae. aegypti (LC50 3.68; LC90 8.92 mg/ml) whereas aqueous extract found to be effective against Cx. quinquefasciatus at a higher concentration. The synthesized AgNPs from A. aspera were highly potent than aqueous extract against all the three tested vectors. The synthesized AgNPs were characterized by UV-visible spectrophotometer, SEM, TEM, FTIR and XRD. This revealed a peak at 452 nm in leaf extract of A. aspera, indicating the production of AgNPs. The synthesized AgNPs were clearly distinguishable with the respective nanometers and the XRD spectrum confirmed the presence of silver ion and it was compared with the standard spectrum peaks. The FTIR spectra of AgNPs exhibited prominent peaks of organic molecules.

View full abstract

The objectives of this study were applying environmental control technologies for comparing the reproductive capacity, the reproductive period and the adjusted period of the breading geese among three production types. A total of 7136 White Roman geese (5947 female geese and 1189 male geese) at 68 weeks of age were randomly divided into period adjustment with a water pad windowless building set (set A), natal period adjustment with traditional open building set (set B) and natural period with traditional open building set (set C). The experimental results indicated that the laying period of the set A, set B and set C are 177, 94 and 147 days respectively. The average laying rate, hatchability and fertilization rate of set A were the highest, but there were not significantly different among three sets (p > 0.05). The average egg production number per female goose for set A was 55 eggs which was the highest. The average product gosling number per female goose of the set A was 41 birds which was more than that of set B (19 birds) and that of set C (26 birds). Therefore, the laying period of goose could be successful adjusted to the non-breeding season and extended it with the water pad environment of control building for reducing summer temperature and short light time.

View full abstract

Jatropha curcas L. is considered a promising next-generation biomass fuel source. Unfortunately, Jatropha seeds contain toxic phorbol esters (PEs) that must be removed from the extracted oil cake for safe use. We used Jatropha oil cake, a byproduct of biodiesel production, and heat-press equipment to evaluate optimum parameters for PE removal while producing a solid fuel with a high energy density. The PE concentration was measured by high-performance liquid chromatography (HPLC), and results showed that the heat-press treatment was effective for PE removal from Jatropha oil cake. Treatment for 15 min at 195 °C under 19.1 MPa pressure produced a solid fuel with PE concentration below the lower detection limit. Our results suggest both treatment temperature and pressure are important factors for PE removal.

View full abstract

The objective of this research was to develop an unmanned surface vehicle (USV) using global positioning system (GPS) compass for autonomous navigation in a paddy field. The surface vehicle used in the research was a radio-controlled air propeller vessel modified into an unmanned surface vehicle platform. The GPS compass was attached to the top of the USV platform as the navigation sensor to provide the position and heading angle. The USV platform can navigate automatically on predefined pathways. From the trajectory data of line-following navigation measured by a total station, the root mean square (RMS) lateral error from the target path was 0.25 m in a no-wind day. The ultimate goal of the research is to realize autonomous herbicide application and paddy growth monitoring based on the USV platform.

View full abstract

Objective of this research was to evaluate the performance of single and multi-GNSS receivers and investigate the different capability under different modes of the multi-GNSS receiver for positioning assessment under stationary and moving conditions in typical Korean agricultural sites such as open field, orchard, and mountainous area. During stationary tests of the single-GNSS receiver (Model: R100, Hemisphere DGPS) with differential correction, the Twice the Distance Root Mean Square values (2DRMS) values were found as 0.162 m, 0.196 m, and 1.720 m in open field, orchard, and mountainous area, respectively. For multi-GNSS receiver (Model: SIGMA-G3T, JAVAD GNSS Inc.) with Precise Point Positioning (PPP) mode, the 2DRMS values were found as 0.077 m, 0.162 m, and 0.929 m for carrier phase differential (RTK) with fixed ambiguities (pd) with QZSS (Quasi-Zenith Satellite System) signal in open field, orchard, and mountainous area, respectively. During the moving tests of the single-GNSS receiver, the Root Mean Square Error (RMSE) values were found as 0.168 m, 0.221 m, and 1.372 m in open field, orchard, and mountainous area, respectively. For multi-GNSS receiver with PPP mode, the RMSE values were found as 0.152 m, 0.182 m, and 1.13 m for pd with QZSS signal in open field, orchard, and mountainous area, respectively. Number of satellites tracked by the multi-GNSS receiver was greater than the single-GNSS receiver in all cases. This research provides capability and accuracy of a multi-GNSS receiver and comparison with a single-GNSS, which would be helpful for selecting appropriate receivers and methods in various agricultural conditions.

View full abstract

The hysteresis test was performed to measure the hysteresis properties of Fuji, Golden and Red Delicious apples. Loading speed of the texture analyzer was 2.5 mm/min and loading deformation set 1.0 mm. Hysteresis parameters were compared with the viscoelastic parameters presented by the oscillatory test. Correlation coefficients between viscoelastic parameters and hysteresis parameters was significantly high for Golden Delicious apple, but low for Fuji and Red Delicious apples. For Golden Delicious apple, correlation coefficients were −0.85, −0.81 and −0.80 for hysteresis loss and 0.84, 0.85 and 0.86 for degree of elasticity, with phase lag, loss modulus and dissipated energy, respectively. Multiple linear regression analysis results for three apple varieties that phase angle, loss modulus, complex modulus and dissipated energy had the adjusted R-square values of 0.532–0.687 for calibration model with statistical significances at p < 0.001 and the validation correlation coefficients of 0.704–0.780, when independent variables measured by the oscillatory test were energy loss, hysteresis loss or hysteresis modulus. It should be noted that the hysteresis and the oscillatory tests take quite different approaches to characterize hysteresis phenomenon of apples.

View full abstract

This paper presents a selective ditcher for sugar cane plantings. The proposed scheme is based on a mechanical driller, which is used to make a ditch where a seed can be planted. An infrared electronic beam is used to detect sugar cane plants, which are remained from the previous crop. The main objective of the proposed implement is to prepare the field to re-populate the current crop and to preserve the existing strain. The driller is based on a commercial and customized mechanical transmission, which is coupled to a tractor's motor using metal chains and gears. The proposed ditcher was mounted in a metallic base, which can be elevated and pulled by a tractor. Infrared beam circuit sends visual and audible warnings to a human operator when a sugar cane plant is detected. Different visual and audible warnings are send to the operator when a sugar cane plants are not detected within a pre-established time window. This circuit uses a 38 kHz carrier signal to reduce a possible false triggering caused by daylight, also the optical detector can discriminates small objects like dead branches and leaves. Diagrams of mechanical parts are shown, and an explanation of the infrared beam operation is presented.

View full abstract

In chickpeas, the seed size is a critical phenotype that needs to be evaluated carefully during variety development. The sieve analysis used for determining seed size distribution in legumes is labor intensive and time consuming method. An image-based method for sizing chickpeas seeds was developed in this study. Samples from a total of 72 plots from two different locations were harvested and seed size was analyzed. The results show that seed size calculated from image-based method was highly correlated to the ground-truth data, with a correlation coefficient of 0.90. The image processing technique provides rapid evaluation of seed size for phenotyping chickpeas and the method also can be adapted for similar seed types.

View full abstract

In this study, power demand leveling technologies were evaluated through the adjustment of electrical equipment operating times based on the results of a measurement survey on livestock feeding management system electricity usage. The results showed peak power demand at two specific times. One was during milking time, when a pipeline milker, a bulk cooler and other milking equipment were used. In the other case, power demand peaked early in the morning and at night, when electric water heaters were in operation, due to the large number of milking cows and the time-consuming milking method used. In either case, it was found that ventilation fans and other incidental facilities used over extended periods were major consumers and accounted for the base of power demand, and that power consumption would definitely be reduced by peak power demand leveling through adjustment of operational methods for this equipment. It was found that operational control involving the introduction of inverters and the operation of ventilation fans only in parlors and holding areas during milking reduced daily power consumption by utmost 40% on farms with milking parlors and by approximately 30% on farms without. The use of an ice builder to pre-cool raw milk on large-scale farms could reduce daily power consumption by approximately 13%. When combined with the reduced power consumption from operational control of ventilation fans, power consumption could be reduced by over 50%.

View full abstract

Ultraviolet–visible (UV-VIS) spectral properties of eye fluid were used to classify Japanese dace fish into fresh or spoiled groups by support vector machine (SVM), linear discriminant analysis (LDA) based on principal component analysis (PCA) scores and using a soft independent modeling of class analogy (SIMCA) classification technique. These models were then evaluated in terms of their sensitivity, specificity and overall accuracy. The UV-VIS absorbance spectra (250–600 nm) of eye fluid from 168 fishes and the K value of fish flesh were measured at 3 h intervals for 36 h. In the SVM model, the sensitivity and specificity for fresh fish was 100%, whereas in the LDA and SIMCA models it was 100% and 90%, and 80% and 90% respectively. For the spoiled group fish the sensitivity and specificity result was 100% for the SVM model, while in the LDA and SIMCA models it was 90% and 100%, and 90% and 80% respectively. The overall classification accuracy was 100%, 93% and 87% for the SVM, LDA and SIMCA models respectively. These results, particularly for the SVM model, indicate that the spectral absorbance of fish eye fluid in the UV-VIS region can accurately classify fish into fresh and spoiled groups.

View full abstract

The use of machine vision technology for nondestructive online measurements of cucumber parameters was investigated. This technology was first used to capture images of a cucumber canopy. Next, a segmentation algorithm (excess green minus excess red (ExG-ExR)) was used to extract the cucumber canopy area and image parameters (i.e., coverage ratio, canopy length and canopy width). These parameters were combined with those obtained by manual measurements (i.e., stem height, stem diameter, leaf number, and fruit number) to generate five inversion models for four cucumber growth parameters. The results showed that the ExG-ExR segmentation method yielded a 99.5% contact ratio and a 98.2% recognition rate in the extraction of the cucumber canopy region. The inversion models were validated with new images using the following three different cultivation modes: 4 × 2, 4 × 3 and 4 × 4. The inversion results showed that the coefficients of determination (R²) between the measured values and inversion values of stem height, stem diameter, leaf number, and fruit number exceeded 0.921, 0.899, 0.95 and 0.908, respectively. Thus, the inversion method can provide nondestructive online measurements of cucumber parameters.

View full abstract

Black soil and brown soil are special soil group containing clay and sandy loam respectively in the P. R. of China. As one of the main corn (maize) and peanut belts in the world respectively, the areas suffer from continuous cropping injury due to continuous planting. To improve conditions, it is recommended that the top soil and subsoil should be displaced and crop residue on the soil surface should be buried into the subsoil to retain the rainwater. These can be accomplished with a special plough which we designed and built. The results show that after operation, about 70% of the dark top soil fell down to the 700 mm depth. The crop residue was buried at a depth of 300–400 mm. A total draught of this plough was measured at 39.5 kN on the black soil field and 29.8 kN on the brown soil field including the tractor running resistance.

View full abstract

In this paper, the thin layer potato drying process by a laboratory scale infrared-convective dryer is investigated. The experiments were accomplished in three levels of slice thickness; 3, 5 and 7 mm, and three levels of infrared power; 500, 700 and 900 W. Drying took place entirely in the falling rate period. The results show that increasing the infrared power leads to a decrease in the moisture content, and drying time of samples, but increased the drying rate, shrinkage, and effective moisture diffusivity. The results also indicated that by increasing the thickness, the effective moisture diffusivity and drying time increased while the drying rate and shrinkage decreased. Eight thin-layer drying models were fitted on the experimental data. The models were compared according to three statistical parameters of the correlation coefficient (R²), root mean square error (RMSE), and reduced chi-square (χ²). The obtained results indicated that the page model could satisfactorily describe the drying curve of potato slices with R² = 0.9991–0.9997, RMSE = 0.0050–0.0095, and χ² = 1.3E-05–9.6E-05 under different operational conditions.

View full abstract

An important aspect of research in electrostatic force field applications to liquid sprays involves pesticide spraying, painting, printing, thin film coating, medical, Nano biotechnology, transportation etc. The desired attributes of such spraying are uniform deposition onto both directly exposed (adaxial) and obscured (abaxial) crop surfaces which minimizes the off-target losses of active ingredients to soil, water, atmosphere and provides economic pest control. This paper presents an overview of electrostatic spraying technologies in the field of agriculture and perishable fruits/food products emphasizing the key role of advanced electrostatic spraying instrumentation and chronicles the scientific innovations in the parlance of providing cost effective and reliable commercial systems along with an insight on the needs of future research perspectives and directives.

View full abstract

Sea buckthorn (SBT) is an ideal plant for ecological management and thus planted widely in western China. Its fruit is of high nutritional and medicinal values. However, its economic value is far from development because of high cost for harvesting SBT fruits. Mechanical vibration is one of feasible way to make fruit separation. To design proper vibratory harvesters for tree crops, the vibration harvesting mechanism of SBT was simulated and analyzed by the finite element method. First, a three-dimensional solid model of SBT tree was built by Pro/E and imported into ANSYS. Next, modal analysis was performed to determine the natural vibration properties of SBT tree such as the natural frequency and vibration mode. Finally, harmonic response analysis was applied to determine the steady-state response when a sine load was added to the SBT tree. The modal analysis results indicated that the first twenty order natural frequencies of SBT tree varied from 6.6 Hz (the first order frequency) to 31.8 Hz (the twentieth order frequency). Results of harmonic response analysis showed that the application of vibration force to the side branches is effective than to the trunk, with a slight damage to the tree. Moreover, the vibration force applied to the side branches was 58–78 N with a frequencies range of from 20 to 30 Hz, which ensured that the majority of SBT fruits were harvested from the tree. The simulation analysis results obtained in this study could provide a basis for the design and development of SBT vibration harvesters.

View full abstract

This study presents the biohydrogen production from rice mill wastewater using mutated Enterobacter aerogenes obtained from random mutagenesis of wild E. aerogenes using UV and ethidium bromide (EtBr). The mutants obtained were screened based on sugar utilization efficiency and the best mutant was selected for further studies. Maximum hydrogen production of 1.92 mol H₂/mol sugar was observed with EtBr mutant, whereas 1.72 mol H₂/mol sugar was observed with UV mutant. Mutant strains showed 25–35% enhanced hydrogen production than wild strain and the optimum initial pH was found to be 7.0. An efficient mutant strain, E. aerogenes RM08, showed improved growth and enzyme production compared to wild strain. The production hydrogenase was confirmed by SDS-PAGE and enzyme sequencing using MALDI-TOF MS. The hydrogen production and growth data obtained were fitted with Modified Gompertz and Logistic equation. The chemical oxygen demand (COD) reduction of 81% was obtained at the end of 60 h of fermentation.

View full abstract

Certainly people who are working in various agricultural affairs exposed to a lot of noise sources and it has not fully specified all the risks for people who have long been exposed to the noise, yet. In this study, some factors affecting the noise generated by a model PO15538LT Poulan lawn tractor were evaluated. Research factors were including operation type and gear ratio for lawn tractor. Accordingly, factorial experiments in completely randomized design with three replicates were performed. The results of this study indicate that psychoacoustic annoyance correlated strongly with A-weighted sound pressure level analysis (R² = 0.957). The results also show that lawn route caused the lowest mean of A-weighted sound pressure level (80.3 dBA) and mowing operation caused the highest mean of A-weighted sound pressure level (87.9 dBA) for right ear. Also, results indicated that the lowest mean of psychoacoustic annoyance occurred in the case of lawn route (13.1). The highest mean of psychoacoustic annoyance occurred in the case of mowing operation (20.1).

View full abstract

This paper describes the methods for estimating a vehicle's dynamic parameters using a Global Positioning System implementing a Real Time Kinematic scheme (RTK-GPS) and an Inertial Measurement Unit (IMU). An RTK-GPS system and an IMU are used to estimate the vehicle's body sideslip angle and then obtain the relation between the tire's lateral forces and slip angles, and also the tire's cornering stiffness. In order to compare the experimental results two vehicle models are described; the bicycle geometric model and the bicycle dynamic model. The method of least squares was applied to the experimental data in order to obtain mathematical expressions that account for the nonlinearities of the system. It is shown that the measurements performed can be used to estimate the tire sideslip and the tire cornering stiffness. The experimental results are consistent to the predictions made by the models, which verifies the potential of this method to determine a nonlinear mathematical model.

View full abstract