Comparative study of different approaches to solve batch process scheduling and optimisation problems

Effective approaches are important to batch process scheduling problems, especially those with complex constraints. However, most research focus on improving optimisation techniques, and those concentrate on comparing their difference are inadequate. This study develops an optimisation model of batch process scheduling problems with complex constraints and investigates the performance of different optimisation techniques, such as Genetic Algorithm (GA) and Constraint Programming (CP). It finds that CP has a better capacity to handle batch process problems with complex constraints but it costs longer time

Efficacy and Safety of Clearing Heat and Detoxifying Injection in the Treatment of Influenza: A Randomized, Double-Blinded, Placebo-Controlled Trial

Objective. To evaluate the efficacy and safety of CHDI in the treatment of influenza infection. Method. A randomized double-blind, double dummy trial was conducted. Influenza patients with a positive influenza A rapid test diagnosis were randomized to receive CHDI or oseltamivir. Primary outcome was assessed by the median fever alleviation time and clearance time, and secondary outcome was total scores of influenza symptoms. Results. One hundred thirty-nine participants were screened and 34 had a RT-PCR laboratory confirmation of influenza virus infection. Fever alleviation time was 2.5 and 5 hours in CHDI and oseltamivir, respectively, and fever clearance time was 32.5 and 49 hours. The HR of fever alleviation and clearance time shows no significant difference between two groups. Total scores of influenza symptoms descended significantly in both groups after treatment and descended more in CHDI than oseltamivir on day 2. Similar to total symptoms severity score, fever severity score descend more significantly in CHDI than oseltamivir on day 2, and there were no differences on other symptoms. Conclusions. CHDI have a similar effect to oseltamivir in reducing the duration of influenza illness. CHDI was well tolerated, with no serious adverse events noted during the study period

Recovery-based rescheduling and optimisation of batch production processes

A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Master of Science by researchBatch production processes are widely used in the process industries, applied to produce high-value added products with great varieties but in small volumes. The dynamic features of batch production processes contribute to the flexibility of the processes, but also pose big challenges to process scheduling problems. Moreover, disturbances in such a dynamic environment intensify its complexity. In this work, scheduling and rescheduling models on batch production processes are proposed, considering parallel machines allocation, storage capacity and waiting. The rescheduling model addresses process disturbances, such as machine breakdown and rush orders, in a recovery-based approach, which uses the original schedules as a guide to diminish the deviations between new and original schedules. Genetic Algorithms (GA) and Constraint Programming (CP) are applied to solve the models, but the rescheduling model built by CP can be applied to original schedules created by any techniques. According to case studies and experiments on the proposed scheduling and rescheduling approaches, it is found that CP has a better performance for scheduling and rescheduling problems with complex constraints although it cost longer time than GA. It is also found that rush orders exerted bigger influences on the batch production process than machine breakdowns, especially when the breakdowns do not happen on the ‘bottleneck’ machines

Application of Ultrafiltration and Ion Exchange Separation Technology for Lysozyme Separation and Extraction

In this study, the fermentation broth of the recombinant Pichia pastoris strain ncy-2 was studied. After pretreatment, separation, and purification, lysozyme was optimized using biofilm and ion exchange separation. Finally, lysozyme dry enzyme powder was prepared by concentrating and vacuum drying. The removal rate of bacterial cells was 99.99% when the fermentation broth was centrifuged at low temperature. The optimum conditions were: transmembrane pressure of 0.20 MPa, pH 6.5, 96.6% yield of lysozyme, enzyme activity of 2612.1 u/mg, which was 1.78 times higher than that of the original enzyme; D152 resin was used for adsorption and elution. Process conditions were optimized: the volume ratio of resin to liquid was 15%; the adsorption time was 4 h; the concentration of NaCl was 1.0 mol/L; the recovery rate of lysozyme activity was 95.67%; the enzyme activity was 3879.6 u/mL; and the purification multiple was 0.5, 3.1 times of the original enzyme activity. The enzyme activity of lysozyme dry enzyme powder was 12,573.6 u/mg, which had an inhibitory effect on microsphere lysozyme. Its enzymatic properties were almost the same as those of natural lysozyme, which demonstrated good application prospects and production potential

Application of Ultrafiltration and Ion Exchange Separation Technology for Lysozyme Separation and Extraction

In this study, the fermentation broth of the recombinant Pichia pastoris strain ncy-2 was studied. After pretreatment, separation, and purification, lysozyme was optimized using biofilm and ion exchange separation. Finally, lysozyme dry enzyme powder was prepared by concentrating and vacuum drying. The removal rate of bacterial cells was 99.99% when the fermentation broth was centrifuged at low temperature. The optimum conditions were: transmembrane pressure of 0.20 MPa, pH 6.5, 96.6% yield of lysozyme, enzyme activity of 2612.1 u/mg, which was 1.78 times higher than that of the original enzyme; D152 resin was used for adsorption and elution. Process conditions were optimized: the volume ratio of resin to liquid was 15%; the adsorption time was 4 h; the concentration of NaCl was 1.0 mol/L; the recovery rate of lysozyme activity was 95.67%; the enzyme activity was 3879.6 u/mL; and the purification multiple was 0.5, 3.1 times of the original enzyme activity. The enzyme activity of lysozyme dry enzyme powder was 12,573.6 u/mg, which had an inhibitory effect on microsphere lysozyme. Its enzymatic properties were almost the same as those of natural lysozyme, which demonstrated good application prospects and production potential

Scheduling and optimisation of batch plants: model development and comparison of approaches

The application of parallel machines and storage facilities provides flexibility but raises challenges for batch plants. This research proposes a scheduling model in batch plants, considering complex real-world constraints that were seldom addressed together. Two optimisation approaches, genetic algorithm (GA) and constraint programming (CP), are applied to solve the complex batch plant scheduling problem. A case study and scalability tests are conducted to investigate different performance of GA and CP in the problem to prepare for further research application. It is found that the CP approach has a better performance in solving batch plant scheduling problems with complex constraints although it needs longer time. The ‘restart’ search strategy is better than two other search strategies for the CP approach

Real-Time Finger-Writing Character Recognition via ToF Sensors on Edge Deep Learning

Human–computer interaction is demanded for natural and convenient approaches, in which finger-writing recognition has aroused more and more attention. In this paper, a device-free finger-writing character recognition system based on an array of time-of-flight (ToF) distance sensors is presented. The ToF sensors acquire distance values between sensors to a writing finger within a 9.5 × 15 cm square on a surface at specific time intervals and send distance data to a low-power microcontroller STM32F401, equipped with deep learning algorithms for real-time inference and recognition tasks. The proposed method enables one to distinguish 26 English lower-case letters by users writing with their fingers and does not require one to wear additional devices. All data used in this work were collected from 21 subjects (12 males and 9 females) to evaluate the proposed system in a real scenario. In this work, the performance of different deep learning algorithms, such as long short-term memory (LSTM), convolutional neural networks (CNNs) and bidirectional LSTM (BiLSTM), was evaluated. Thus, these algorithms provide high accuracy, where the best result is extracted from the LSTM, with 98.31% accuracy and 50 ms of maximum latency

Influence of Environmental Factors During Ice-Melting Period

The sea cucumber (Apostichopus japonicus) has high economic value and is one of the important mariculture species in northern China. With the continuous development of aquaculture industry, closed or semiclosed pond aquaculture has become the main sea cucumber culture method. The ice-melting period is a special period when the ice on the pond surface melts due to the temperature rise in early spring in northern China. During this period, the ice-melting layer gradually changes the water environment of pond aquaculture from a closed state to external exchange state, resulting in the formation of thermocline and halocline areas and dissolved oxygen stratification in pond aquaculture waters. Some investigations have shown that the thermocline of pond water caused by ice-melting will cause the deterioration of water quality at the bottom of the pond and the outbreak of pathogenic bacteria, which will endanger the health of cultured organisms. Microorganisms are an important part of the pond aquaculture ecosystem. They play an important role in the ecosystem´s material circulation and energy flow and are significant to maintaining its balance. As an important part of the pond aquaculture ecosystem, sediment bacteria not only play a great role in the material circulation and energy flow processes but correlate with the growth, digestion, immunity, and diseases of aquaculture organisms. However, external physical and chemical factors easily affect the pond aquaculture ecosystem´s bacterial structure. Seasonal changes and nutrient input can modulate the species and abundance of bacteria in the pond aquaculture environment, and indirectly affect the growth and health of aquaculture organisms. In recent years, investigations have been carried out on the bacterial community structure in ponds water and sediment. Nonetheless, only few reports comprise the structure and function of the bacterial community during the ice-melting period. Therefore, it is of great theoretical and practical significance to study the structural and functional characteristics of the sea cucumber sediment bacterial community in the pond aquaculture during the ice-melting period. Therefore, this study used the typical shore-based semi-open sea cucumber pond culture in northern China as its research object. A 16S rRNA sequencing library was constructed based on the sediment bacterial community during the icebound, melting, and ablation periods and analyzed using high-throughput sequencing technology. These sequences were used to evaluate the structural characteristics of these bacterial communities and identify the dominant environmental factors affecting them. The results showed that the abundance and diversity of sediment bacterial communities showed an overall downward trend in the ice melting period, fluctuating significantly in the early stage of ice-melting (P < 0.05). Compared with the icebound period, the appearance of thermocline and halocline caused drastic changes in the environmental factors of the bottom water layer. The temperature increase provides a suitable habitat for more microorganisms, accelerating enzymatic reactions and promoting microbial metabolism, which results in the up-regulation of bacteria abundance and diversity in the early melting period. As an important environmental factor in mariculture, salinity can interfere with the metabolism of microorganisms in the water and affect its diversity in sediments. This investigation showed that the bacterial community abundance and diversity in high-salinity conditions were significantly higher than those in low salinity. The substantial changes in the environmental factors destroyed the original sediment bacterial structure during the icebound period, resulting in microbial abundance and diversity fluctuation during the ice-melting period. With the gradual disappearance of the thermocline and salt layers, the pond aquaculture´s environmental factors and bacterial structure tended to be stable. In the ice-melting period, there were significant differences in the structure of sediment bacteria. The differential bacterial communities in the icebound, melting, and ablation periods were Firmicutes, Acidobacteria, and Tenericutes, respectively. Although the relative abundance ratio of microorganisms in different stages is distinct, the first dominant bacteria belong to Proteobacteria, and the relative abundance is higher than 49.04%. The secondary dominant bacteria included Bacteroides in the icebound period, Chloroflexi and Actinobacteria in the melting period, and Planctomycetes in the ablation period. The environmental factors and bacterial community structure showed significant correlation in the sea cucumber culture pond during the ice-melting period (P < 0.05). Temperature, salinity, total nitrogen, and total organic carbon were the dominant environmental factors affecting sediment bacteria. This study will provide a theoretical basis for effectively managing sea cucumber pond aquaculture

Sh3rf2 Haploinsufficiency Leads to Unilateral Neuronal Development Deficits and Autistic-Like Behaviors in Mice

Summary: Autism spectrum disorders (ASDs) include a variety of developmental brain disorders with clinical findings implicating the dysfunction of the left hemisphere. Here, we generate mice lacking one copy of Sh3rf2, which was detected in ASD patients, to determine whether Sh3rf2 is involved in brain development and whether mutation of SH3RF2 is causative for ASD and the mechanisms linking it to ASD traits. We find that mice with Sh3rf2 haploinsufficiency display significant deficits in social interaction and communication, as well as stereotyped or repetitive behaviors and hyperactivity and seizures. Disturbances in hippocampal dendritic spine development, aberrant composition of glutamatergic receptor subunits, and abnormal excitatory synaptic transmission were detected in heterozygous mutants. Remarkably, these defects are selectively unilateral. Our results support a notion that Sh3rf2 haploinsufficiency is a highly penetrant risk factor for ASD, with disease pathogenesis most likely resulting from deficits in synaptic function in the left hemisphere of the brain. : Wang et al. find that Sh3rf2 is important for neuron development and that Sh3rf2 haploinsufficiency in mice results in typical ASD-like behaviors, as well as selective unilateral disturbances in hippocampal dendritic spine development, composition of glutamatergic receptor subunits, and excitatory synaptic transmission. Keywords: autism spectrum disorders, Sh3rf2/POSHER, brain development, synaptic functio