Engineering in Agriculture, Environment and Food最新文献

To optimize sorbitol production through solid state fermentation (SSF) process using response surface methodology (RSM), the central composite design (CCD) was employed in this study in order to minimize the number of experiments needed for the determination of the best combination of parameters for the process optimization. The raw material used in this study was Meranti wood sawdust (MWS) obtained from Gambang Sawmill (M) Sdn Bhd, Gambang Kuantan, Pahang. The type of bacteria used for the study was Lactobacillus plantarum (BAA 793; NCIMB 8826), purchased from the America Type Culture Collection (ATCC). The physical and chemical pretreatment methods were used in the study to recover cellulose from the MSW, followed by the enzymatic hydrolysis process to produce glucose. The last phase of this work was the fermentation process using SSF to convert the produced glucose to sorbitol; this is the section of the study where the parameters were optimized using the RSM. The result of the RSM studies showed that the interactions between moisture content and temperature had a very significant effect with an F value of <0.0001. The highest yield of sorbitol (29.0625 g/L) was obtained when using 50% of moisture content, at a temperature of 35 °C for 10 h of fermentation time. The RSM helped in the optimization of the effective parameters as well as to analyze the interaction between the parameters.

Fourier transform near infrared spectroscopy (FT-NIR) in diffuse reflectance mode was used for the rapid estimation of curcumin, starch and moisture contents in turmeric samples. Thirty samples each of fingers and bulbs from varieties ‘Erode local’ and ‘Salem local’ (n = 120) were used for the study. Calibration models were developed and evaluated to describe the relationship between the three quality attributes with the NIR spectra of the turmeric powder. NIR reflectance spectra were acquired for each turmeric sample at a resolution of 8 cm⁻¹ over a wave number range of 12,500 to 3600 cm⁻¹. Vector normalization, first derivative and first derivative plus vector normalization were used as spectral pre-processing options. The relationship between the acquired spectra of turmeric samples and the quality attributes was examined through partial least square (PLS) regression algorithm. First derivative plus vector normalization technique predicted curcumin content with best accuracy with lowest root mean square error of cross validation (RMSECV) of 0.178% and maximum correlation coefficient for validation plots (R² = 91.9). Vector normalization technique predicted the starch and moisture content with RMSECV and R² value of 0.076%, 96.8 and 0.032%, 81.1 respectively. The results demonstrated that FT-NIR could be used as a rapid technique for quantification of curcumin, starch and moisture content in turmeric rhizomes for online grading in spice processing.

This paper is devoted to determine the concentration of two types of food additives using continuous injection technique supported by a new software designed by the authors. This methodology was developed to determine the tartrazine and sodium benzoate in some locally traded juices and the results obtained were compared with those obtained using traditional methods in the literature. The data is then received by a signal detector and a developed software spectrometer where a spectral scan was used to obtain the maximum wavelength for the two substances, a calibration curve was constructed and measurements obtained to find the actual concentrations of the two substances in the selected juices. It was found that the detection limit and the quantitative limit are 0.229, 0.694 and 0.221, 0.666 ppm for tartrazine and sodium benzoate respectively. This method is simple, fast, accurate, economical and versatile, which makes it a preferred routine method.

In this study, we report the long term operation results of analyses of characteristics of the Rakuno Gakuen University Biogas generation plant (BGP), which has been in operation since March 2000. We evaluated using data for the 11-year period between April 2000 (FY2000), when BGP was built, and March 2011 (FY2010). The average biogas production per unit showed substantial fluctuations during this period, increasing from 20 m³ during the trial operation period in FY2000 to 30–40 m³ in FY2001–FY2006, and then decreasing to 15–25 m³ in FY2007–FY2010. The optimal methane fermentation facility temperature for steady methane gas production was approximately 40 °C. In FY2007, this BGP experienced its first localized functionality decline in energy use, including methane fermentation and power generation facilities. This resulted from changes in the substrate characteristics, inputs, and methane fermentation facility temperature, indicating that operations need to accommodate such changes in the long term.

The change of received signal strength index and packet loss rate under 2.4 GHz radio communication in a persimmon orchard in flowering phase was investigated. Texas CC2530 RF chip and the TinyOS system based WSN nodes were selected as instruments to conduct interwoven tests along a column of persimmon trees and different rows and columns of the orchard, and measure the receiving signal strength and packet loss rate which were in the three different heights from 0.80 m at the bottom of the canopy to 2.80 m at the top. In the tests, distance of each three trees was set as a tested distance, and there were eight tested distances in each row or column totally. Afterwards, all the obtained data underwent regression analysis. The results showed that when the transmitter and receiver were maintained at a fixed height, the received signal strength decreased, while the packet loss rate increased with the augment of tested distance. Furthermore, under the two situations where receiver was at the fringe of persimmon orchard and both transmitter and receiver were in the orchard, the models of signal strength attenuation affected by different factors along a row of persimmon tree were established and evaluated. Additionally, the curved surface graphs of different transceiver heights and different ranks of trees which were drawn by MATLAB software was able to reflect wireless signal transmission characteristics in persimmon orchard straightly.

Appropriate residue management is a key factor underlying successful crop establishment in no-tillage systems. Satisfactory opening and closing of furrows, and uniform seeding depth and seed-spacing are achieved when the design of the residue management unit of the seeder, and machinery settings are correctly selected for the soil type, soil condition, and soil surface residue characteristics. Improper selection of such units or settings can result in blockage of tine furrow openers, with accumulated residues and hairpinning when disc openers are used. This can affect seed-soil contact and result in uneven seedling emergence or sub-optimal plant stand, and reduce crop yield potential. This article critically examines the effectiveness of residue management units of no-tillage sowing equipment in maintaining appropriate levels (e.g., ≥30%) of residue cover on sown rows, preventing the interference of such residue with opening and closing of furrows (blockage), enabling the seed to be correctly placed (depth control, seed-spacing), and by discussing the influence of unit's design on fuel consumption and power (draft) requirements. This review confirmed that smooth disc coulters, finger row cleaners, and their combinations can retain more than the minimum residue cover recommended for no-tillage systems. Power-assisted units can operate with surface residue up to about 9000 kg ha⁻¹ without blockage, but their adoption in developing countries is restricted by relatively high fuel consumption. Future evaluations of residue management units need to be conducted under controlled conditions. Such work will enable parametrization of suitable models (DEM) and will advance the understanding of soil-machine-residue interactions to further assist the design of no-tillage equipment. Priority research areas are presented and discussed.

The enhancement in efficiency of water distribution system can provide water to farmers equally by controlling water loses. The main objective of this study was to quantify canal water distribution and its impact on income of the farmers in selected watercourses of 3-R distributary before and after the remodeling of outlets in district Bahawalnagar, Pakistan. The result showed that the water supply to the farmers at the tail reach was less than those at head and middle reaches of the watercourses. The tail end farmers had to spend more money to pump groundwater and the net income of the farmers decreased with increase in distance from the outlets before and after remodeling of the outlets. The net income of head, middle and tail reach farmers along the watercourses decreased from 20 to 25 percent and yield of wheat reduced approximately 30–40% after remodeling of the outlets. It was concluded that newly designed outlets did not show any improvement in distribution of canal water and this inequity of canal water distribution reduced the income of the farmers.

A single-acting (3 × 3) 510 mm powered disc harrow was developed to achieve timeliness in operation in the extensively followed rice-wheat cropping system by reducing tillage passes with the proper incorporation of residues left after rice cultivation. Experiments were carried out at forward speeds of 3.69, 4.67 and 6.55 km h⁻¹ corresponding to speed ratios of 4.74, 3.75 and 2.67, respectively and at 90, 120 and 140 mm operating depths in sandy clay loam soil having an average moisture content of 12 ± 0.75% (db) and cone index of 930 ± 40 kPa. Its comparison was also made with conventional free rolling disc tilling which generally requires more passes. Optimum performance in terms of tillage performance index was achieved at speed ratio of 3.75 with a reduction in draft, slip, and clod size by 30–36%, 53.47–72.25% and 39.20–60.73%, respectively at the cost of 14.28–18.40% increase in fuel consumption (l ha⁻¹) when operated at depth of 120 mm as compared to free rolling mode indicating better energy utilization. Effect of multiple passes of tilling on soil compaction beneath the tillage depth (100–200 mm) was also studied from separate experiments. Soil compaction was observed to be 4.71–7.17% and 5.21–6.86% lesser as compared to that obtained with rotavator after first and second passes of tillage, respectively. However, it was about 0.38–3.00% and 3.00–5.32% more compared to free rolling disc tilling after first and second passes, respectively. Reduced number of passes required for preparing seedbed with powered disc justifies its use for carrying out the tillage.

Volume is an important parameter in determining the density of aquatic products. However, due to the distended variation in shape and size of these products, it is difficult to precisely estimate their volume in water. In this study, we proposed a technique known as Helmholtz resonance for estimating the volume of fish in water. In order to do this, a closed cavity resonator was designed and utilised as an underwater prototype to demonstrate the potential for fish volume measurement. However, such a closed cavity resonator is thwarted by the need to open, insert the fish samples and close for measurement to be done. As a potentially more viable alternative, an open cavity resonator, which would allow fish to be measured without the need to close or lock the cavity was developed. Furthermore, this has the potential for automatic fish volume estimation where fish can pass through such an opening on the side of the resonator's cavity for measurement. Similar to the closed cavity resonator, as the volume of sampled fish increased, resonance frequency decreased in the open cavity resonator. The damping of the resonance frequency was caused by the viscous fish flesh and the elastic swim bladder in the anterior chamber of the model fish, a teleostean fish. By use of empirical equations, a linear regression model (R-squared) with an accuracy of 0.99 in the open cavity resonator was obtained. An underwater open cavity Helmholtz resonator has the potential for fish volume measurement.

Unmanned ground vehicles (UGVs) are becoming popular for use in agricultural environments. These unmanned systems are implemented in order to address human labor shortages throughout the agricultural industry, and improve food safety throughout the production cycle of produce crop. Common uses of UGVs in agriculture include: detection of animal fecal matter, surveys of crop growth, detection of crop damage from storms or floods, and detection of unwanted pests or molds. Navigation of crop rows is typically accomplished using vision-based cameras and global positioning system (GPS) units. Machine vision strategies are implemented to detect crop row contours and edges to ensure proper navigation of rows without damaging crops. A number of other control and navigation strategies exist for autonomous movements of UGVs. This paper provides a survey and overview of autonomous navigation strategies for UGVs with applications to agricultural environments.