Binary Sensors-Based Privacy-Preserved Activity Recognition of Elderly Living Alone Using an RNN.

The recent growth of the elderly population has led to the requirement for constant home monitoring as solitary living becomes popular. This protects older people who live alone from unwanted instances such as falling or deterioration caused by some diseases. However, although wearable devices and camera-based systems can provide relatively precise information about human motion, they invade the privacy of the elderly. One way to detect the abnormal behavior of elderly residents under the condition of maintaining privacy is to equip the resident's house with an Internet of Things system based on a non-invasive binary motion sensor array. We propose to concatenate external features (previous activity and begin time-stamp) along with extracted features with a bi-directional long short-term memory (Bi-LSTM) neural network to recognize the activities of daily living with a higher accuracy. The concatenated features are classified by a fully connected neural network (FCNN). The proposed model was evaluated on open dataset from the Center for Advanced Studies in Adaptive Systems (CASAS) at Washington State University. The experimental results show that the proposed method outperformed state-of-the-art models with a margin of more than 6.25% of the F1 score on the same dataset.

[Extract berberine hydrochloride by aqueous two-phase system].

OBJECTIVE: To study the aqueous two-phase system which could be used for extraction of berberine hydrochloride. METHODS: Three aqueous two-phase systems were used for extraction experiment firstly, the best one was chosen from that, and then the single factor experiment and orthogonal experiment were carried out. RESULTS: 10 mL 95% ethanol with 10 mL 2.2 mol/L ammonium sulfate could make a aqueous two-phase system, added 600 mg berberine hydrochloride whose purity was 53.22% into it, regulated its pH to 4, then the system was put into water-bath heater (70 degrees C) for 30 min, the extraction rate could reach 99.29%; Collected the extraction liquid, dried it under 40 degrees C, the purity of berberine hydrochloride was 88.43%. CONCLUSION: This system is a suitable aqueous two-phase system for extraction of berberine hydrochloride.