Comparative Study of Underground Pit Grain Storage System through Use of Different Lining Materials

Sorghum occupies highest area of cultivation in East and West Hararghe of Ethiopia. Farmers in the area are poor and do not afford an advanced storage systems. Hence, storage is done mainly in underground pit storage with different lining materials. This study was therefore aimed at evaluating those different lining materials in maintaining the sorghum quality. Four different lining materials which are commonly used by the farmers (mud/straw/cow dung mixture (3:3:1 ratio), plastic (thick rubberized canvas), chaff and cement) were used. Ten pits (duplicated), flask shaped with 1 m depth and 1 m diameter with a capacity of about two quintals (200 kg) were constructed. The finding in this comparative study is that, among all underlining materials, underground pit with plastic lining material was good barrier compared to all linings. Moisture migration to the grain increased in each month in all lining materials and the least was recorded in plastic lining. Germination capacity and thousand grain weight were reduced significantly in each material except plastic lining which showed the least change compared to the others. Fungi infestation was also increased in all underground pits with different lining materials. However, lower infestation was found in plastic and cement linings. Based on the quality measurements, plastic lining showed the least change in grain quality compared to the others. It can be concluded that, since the farmers can’t afford advanced storage system, it can be recommended to use plastic lining material among the existing lining materials

Adversarial Attacks on Deep Neural Networks for Time Series Classification

Time Series Classification (TSC) problems are encountered in many real life data mining tasks ranging from medicine and security to human activity recognition and food safety. With the recent success of deep neural networks in various domains such as computer vision and natural language processing, researchers started adopting these techniques for solving time series data mining problems. However, to the best of our knowledge, no previous work has considered the vulnerability of deep learning models to adversarial time series examples, which could potentially make them unreliable in situations where the decision taken by the classifier is crucial such as in medicine and security. For computer vision problems, such attacks have been shown to be very easy to perform by altering the image and adding an imperceptible amount of noise to trick the network into wrongly classifying the input image. Following this line of work, we propose to leverage existing adversarial attack mechanisms to add a special noise to the input time series in order to decrease the network's confidence when classifying instances at test time. Our results reveal that current state-of-the-art deep learning time series classifiers are vulnerable to adversarial attacks which can have major consequences in multiple domains such as food safety and quality assurance.Comment: Accepted at IJCNN 201

Modifying the Symbolic Aggregate Approximation Method to Capture Segment Trend Information

The Symbolic Aggregate approXimation (SAX) is a very popular symbolic dimensionality reduction technique of time series data, as it has several advantages over other dimensionality reduction techniques. One of its major advantages is its efficiency, as it uses precomputed distances. The other main advantage is that in SAX the distance measure defined on the reduced space lower bounds the distance measure defined on the original space. This enables SAX to return exact results in query-by-content tasks. Yet SAX has an inherent drawback, which is its inability to capture segment trend information. Several researchers have attempted to enhance SAX by proposing modifications to include trend information. However, this comes at the expense of giving up on one or more of the advantages of SAX. In this paper we investigate three modifications of SAX to add trend capturing ability to it. These modifications retain the same features of SAX in terms of simplicity, efficiency, as well as the exact results it returns. They are simple procedures based on a different segmentation of the time series than that used in classic-SAX. We test the performance of these three modifications on 45 time series datasets of different sizes, dimensions, and nature, on a classification task and we compare it to that of classic-SAX. The results we obtained show that one of these modifications manages to outperform classic-SAX and that another one slightly gives better results than classic-SAX.Comment: International Conference on Modeling Decisions for Artificial Intelligence - MDAI 2020: Modeling Decisions for Artificial Intelligence pp 230-23

Post-Harvest Challenges of Marketers of Selected Neglected Crops in South-East and South-South, Nigeria

Research works on neglected crops have been based on production improvement with little or no attention on other key value chains such as marketing. This study examined the challenges of marketers of selected neglected food crops (Bambara nut: Vigna subterranean; Breadfruit: Artocarpus altilis and Bush-mango: Irvingia gabonensis) in Southern Nigeria. A multistage random sampling technique was used to select 144 respondents from 6 major markets and structured questionnaire administered, while descriptive analysis was used to analyze the data. The results revealed the mean age of the marketers as 40 years, 86.8% females and 83.3% literate. The mean number of house-holds was seven (7) persons and marketing experience of 10.1 years. The average quantities of purchase for each crop were 5131.1250kg (Bambara nut), 77.4288kg (Breadfruit) and 246.7600kg (Bush-mango). The average lengths of storage of these crops before selling were 102, 30 and 77days for Bambara nuts, Breadfruits and Bush-mango respectively. Causes of losses were attributed to the following; 27.7% insect and pest, 42.4% mold, and 29.9% rodents. About 2.8% of the neglected crop marketers used sniper for the preservation of their crops, while 27.8% out of the other 97.2% used bio-insecticide.  Constraints militating against the sale of these neglected food crops in the study area were; lack of organized market, lack of financial support, high cost of transportation, strenuous market purchase, and susceptibility to pests, and lack of storage facility. The study therefore, recommends that marketers be encouraged to form or belong to trade associations or cooperative societies to enhance access to loan, and research into Post-harvest technology related to the selected food crops (such as storage structures and processing equipment) should be developed and disseminated appropriately

Comparison of dry matter losses and aflatoxin B1 contamination of paddy and brown rice stored naturally or after inoculation with Aspergillus flavus at different environmental conditions

The objective of this study was to compare the effect of different storage moisture conditions (0.70, 0.85, 0.90 and 0.95 water activity, aw) and temperatures (20, 25, 30 °C) on (a) respiration rates (R) and dry matter loss (DML) of paddy and brown rice and (b) quantify aflatoxin B1 (AFB1) production by isolates of Aspergillus flavus from the rice samples and (c) inoculation of both rice types with A. flavus under these storage conditions on R, DML and AFB1 contamination. There was an increase in temporal CO2 production with wetter and warmer conditions in naturally contaminated rice. Higher R and consequently, % DML, were generally found in the brown rice (21%) while in paddy rice this was only up to 3.5% DML. From both rice types, 15 (83.3%) of 18 A. flavus isolates produced detectable levels of AFB1 in a range 2.5–1979.6 μg/kg. There was an increase in DML in both rice types inoculated with A. flavus as temperature and aw were increased. Interestingly very little AFB1 was detected in paddy rice, but significant contamination occurred in the brown rice. The %DML in the control and A. flavus inoculated rice increased with temperature and aw at both 25 and 30 °C from 1-2% to 15–20% DML at 30 °C and 0.95 aw. All the inoculated rice samples had AFB1 levels above the EU legislative limits for contamination in other temperate cereals and products derived from cereals (=2 μg/kg). Even samples with % DML as low as 0.2% had AFB1 contamination levels twice the limits for other cereals. These results suggest that the mycotoxin contamination risk in staple commodities like rice, is influenced by whether the rice is processed or not, and that measurement of R rates can be used to predict the relative risk of AFB1 contamination in such staple commodities

Influence of type and shelf-life on two brands complementary food in color, vitamins, and sensory evaluation

The aim of our study was to measure the color by system CIELAB, sensory analysis, and determination of vitamins in children vegetable complementary feeding (carrot, vegetable mix) with the option to extend shelf life from eighteen to twenty-one months. Complementary children food was obtained from private factory in the Czech Republic. In this research there were used only carrot and vegetable mix samples. To determine the color changes by system CIELAB and determination of vitamins, samples of mash were analyzed before filling into jars and sterilization, and then immediately after sterilization. Further analyzes were performed for twenty-one months, with run of every three months (p <0.05). The comparison of color CIELAB parameter L* (lightness) for two process steps: raw mash and sterilized mash; there were significant differences when processing (p <0.0001, r2 = 0.9983). Mainly, the parameter L* (Lightness) showed statistically significant differences in carrot and garden mix (p <0.05). β-carotenes such as provitamin A, is in food of plant origin stable substance in the absence of air. Storing time had significant influence on contain of β-carotenes, the mean content during twenty-one months was 0.862 mg.100g-1 (p <0.05, r2 = 0.2300). There were no significant differences in dark storing (p >0.05, r2 = 0.1097). The sensory evaluation showed statistical differences in all descriptors (color saturation, uniformity of color, consistency and homogeneity) (p <0.05) in course of months of storage time and storage conditions (daylight-dark). The results can be recommended to manufacturers, extending the period of minimum shelf life of the required three months to twenty-one months due to instability as characteristics of color and textural properties which were obtained

Karakterisasi Serat Dari Tanaman Biduri (Calotropis Gigantea) Dan Identifikasi Kemungkinan Pemanfaatannya Sebagai Serat Tekstil

Calotropis gigantea atau yang dikenal dengan nama Biduri merupakan tanaman perdu/ilalang yang dapat tumbuh liar di pesisir pantai, dataran tinggi bahkan di lokasi tanah keras dan berkapur. Di bagian dalam buahnya terdapat serat halus yang berpotensi untuk dijadikan bahan baku serat tekstil. Untuk mengetahui karakteristik dan potensi pemanfaatannya, pada penelitian ini dilakukan karakterisasi berdasarkan morfologi, sifat kimia, fisika dan mekanik serta uji pemintalan. Sampel Calotropis gigantea yang digunakan diambil dari Semarang, Pangandaran, Ciamis, Cilacap dan Yogyakarta. Untuk pembanding, dilakukan pula pengamatan pada serat kapas dan kapok. Berdasarkan pengamatan diketahui bahwa morfologi serat Calotropis gigantea berbentuk hollow (berongga) dengan volume hollow 92,3 – 94,7 % dan rendemen serat 8,9 % dari berat buah. Kandungan selulosa 66,52 – 71,62 %; lignin 13,45 - 14,08 %; kadar air (MC 7,3 %; MR 7,9 %); rasio daya serap minyak : air 60,89 kali (g/g) dan 57,06 kali (g/cm3). Sifat fisika Calotropis gigantea : panjang ± 1,25 inchi; kerataan panjang 84,0; kekuatan per berkas 37,8 g/tex; efek kilau tinggi (+b 19,6); indeks serat pendek 7,8; mulur rendah (3,9 %); ringan dan halus (2,02 m); kaku; permukaan licin; mengapung di air dan minyak (buoyant). Hasil uji pemintalan 100 % Calotropis gigantea menunjukkan bahwa kualitas benang masih di bawah standar mutu benang ring tenun (carded) kapas 100 % (SNI 08-0033-2006). Berdasarkan hasil pengamatan dan penelitian, serat dari buah Calotropis gigantea memiliki karakteristik potensial sebagai bahan tekstil seperti filler untuk material pengapung dan penyerap tumpahan minyak