Nonlinear analysis and prediction of soybean futures

We use chaotic artificial neural network (CANN) technology to predict the price of the most widely traded agricultural futures – soybean futures. The nonlinear existence test results show that the time series of soybean futures have multifractal dynamics, long-range dependence, self similarity, and chaos characteristics. This also provides a basis for the construction of a CANN model. Compared with the artificial neural network (ANN) structure as our benchmark system, the predictability of CANN is much higher. The ANN is based on Gaussian kernel function and is only suitable for local approximation of nonstationary signals, so it cannot approach the global nonlinear chaotical hidden pattern. Improving the prediction accuracy of soybean futures prices is of great significance for investors, soybean producers, and decision makers.

The Existence test of Salmonella thypii and Eschericia coli of Corn Ice at Padang Bulan’s Traditional Market, Medan

Food hygiene is an important factor to protect ourselves from the contamination of germs and bacteria that enter through these food intermediaries. Food contaminated by bacteria will cause disease and can cause death if not treated immediately. Common bacteria that contaminate food are Salmonella thypii and Eschericia coli. Both types of bacteria are a group of gram-negative bacteria in the form of bacilli. This study aims to analyze and identify the bacteria S. thypii and E. coli found in corn ice samples. The study was conducted with a descriptive method by conducting a bacteriological examination to determine the quality of sample cleanliness. There are 3 stages in this study, the first stage is calculation of amount of total bacteria (total plate count), analysis of S. thypii and E. coli bacteria and identification with Gram staining. The results showed 40% of samples tested is positive for S. thypii and 60% for E. coli. The largest amount of total bacteria was shown by samples 1 and 3, which were 78 cfu and 52 cfu, respectively. The presence of S. thypii and E. coli bacteria in the sample is thought to be due to poor hygiene factors in the processing of the drink