Optimization of Process Parameters of Continuous Microwave Drying Raspberry Puree Based on RSM and ANN-GA

To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexes(average temperature,average moisture content,average retention rate of the total anthocyanin content,temperature contrast value,and moisture dispersion value)were investigated via the response surface method(RSM)and the artificial neural network(ANN)with genetic algorithm(GA).The results showed that the microwave intensity and drying time dominated the changes of evaluation indexes.Overall,the ANN model was superior to the RSM model with better estimation ability,and higher drying uniformity and anthocyanin retention rate were achieved for the ANN-GA model compared with RSM.The optimal parameters were microwave intensity of 5.53 W•g^(-1),air velocity of 1.22 m·s^(-1),and drying time of 5.85 min.This study might provide guidance for process optimization of microwave drying berry fruits.

Optimization of Intermittent Variable Power Microwave Heating Process for Blueberry Pulp

To improve heating uniformity and anthocyanin content of the blueberry pulp under microwave heating,the intermittent variable power microwave heating technology was introduced in the study.The effects of technology parameters in terms of high microwave intensity heating time,intermittent time,low microwave intensity and low microwave intensity heating time on the blueberry pulp quality parameters(heating uniformity,average moisture content,the highest temperature and anthocyanin content)were investigated by using the response surface method.The results showed that the longer heating time under different microwave intensities resulted in the poorer heating uniformity.The intermittent stage promoted heat and mass transfer within the pulp and reduced the temperature difference and moisture gradient within the pulp,which enhanced desired uniformity of temperature and moisture distribution before entering the low microwave intensity heating stage.Therefore,the longer the intermittent time,the greater the heating uniformity.The optimal parameters were developed as high microwave intensity of 4 W·g^(-1),high microwave intensity heating time of 9.86 min,intermittent time of 10 min,low microwave intensity of 2.2 W·g^(-1)and low microwave intensity heating time of 6 min.This research might provide guidance for microwave heating berry fruits.

Kinetic Mechanisms for Preparing Silymarin via Microwave-assisted Extraction

The kinetic mechanism for the preparation of silymarin from milk thistle seeds was studied during the microwave-assisted extraction （MAE） process. The results showed that the transfer rate of silymarin from milk thistle seeds increased with the microwave output power and temperature during MAE processing. The apparent extraction rate constant k （s-1） was 1.2028×10-2 , 1.2248×10-2 , and 1.2485×10-2 , and diffusion coefficient D （m2·s-1 ） was 4.21×10-10, 4.29×10-10 , and 4.37×10-10 at the microwave temperatures of 383, 393, and 403 K, respectively, in the silymarin MAE process. With the help of scanning electron microscopy （SEM）, the microstructures of the samples extracted by MAE were observed. The results revealed that the increased efficiency and rate of MAE of silymarin could be attributed mainly to the subsequent cell change resulting from superheating effects during MAE.

Rapid Non-destructive Detection for Molds Colony of Paddy Rice Based on Near Infrared Spectroscopy

Near infrared spectrometer technology under a wavelength range of 918-1045 nm was used to rapidly detect paddy rice that was stored at 5℃, 15℃ and 25℃. A total of 121 paddy rice samples were collected from artificial infection with moulds to build the calibration models to calculate the total number colony of moulds based on the principal component regression method and multiple linear regression method. The results of statistical analysis indicated that multiple linear regression method was applicable to the detection of the total number colony of moulds. The correlation of calibration data set was 0.943. The correlation of prediction data set was 0.897. Therefore, the result showed that near infrared spectroscopy could be a useful instrumental method for determining the total number colony of moulds in paddy rice. The near infrared spectroscopy methodology could be applied for monitoring mould contamination in postharvest paddy rice during storage and might become a powerful tool for monitoring the safety of the grain.

Improvement of Temperature Uniformity of Instant Rice Inside Plastic Rectangular Container Under Microwave Reheating

To improve the temperature uniformity of instant rice in a plastic rectangular container, during microwave reheating, the changes of temperature distribution were analyzed by using experiment and simulation method. A three-dimensional finite element model was established to describe microwave reheating of instant rice to predict the temperature. The results showed that the highest temperature occurred at the corners and bottom layer. The cold spots were located in the sample interior center. The simulation results in the model matched relatively with the experimental results. A method of intermittent microwave reheating was proposed to improve the temperature uniformity of convenient rice, and the optimal combination was the time of microwave reheating was 180 s, and the intermittent ratio was 1 : 3.

Temperature Simulation of Berry Slices Under Microwave Vacuum Puffing Conditions

In order to study the temperature simulation of berry slices in microwave vacuum puffing process, numerical simulation method was used to simulate the temperature in different time according to theoretical calculation result and the deviation had been verificated throughout the experiment. The better uniform of temperature between experiment and simulation could be concluded except in the period of rapid temperature increase. The temperature reached the high point of 130.25℃ in the middle point of slices at 100 s, while the temperature was over 50℃ in external parts of slices for the reason of thermal diffusion. Conclusions could be drawn that the model was effective and numerical analysis could simulate the temperature simulation for berry leather in microwave vacuum puffing process.

Process Parameter Study on Microwave-assisted Foam-mat Drying Properties of Corn Soaking Water

In order to study the microwave-assisted foam-mat drying properties of corn soaking water and optimize process parameters, a quadratic regression orthogonal rotary method was used to analyze the influence of microwave power, material weight, material thickness and drying time on moisture content（dry basis）, color value and protein content. Results showed that the primary and secondary sequence of parameters with regard to moisture content（d. b.） was drying time, microwave power, material weight and material thickness; the primary and secondary sequence of parameters with regard to color value was material weight, drying time, microwave power and material thickness; the primary and secondary sequence of parameters with regard to protein content was drying time, material weight, microwave power and material thickness. Optimum conditions were obtained as microwave power of 560 W, material weight of 46.88 g, material thickness of 6.20 mm and drying time of 8.01 min. The results might provide the theoretical basis and technical support for the microwave-assisted foam-mat drying of corn soaking water to produce yeast protein power.

一种基于多尺度滑动窗口图像检测行人的新方法

针对行人检测领域的相关现实问题,传统机器学习算法通常采用对整幅图片以滑动窗口逐步检测的方法解决,这样会因检测非必要背景窗口过多而大大降低计算效率,针对上述问题提出一种基于多尺度滑动窗口图像检测行人的新方法。首先以滑动窗口遍历图像,对整幅图片进行显著性检测,然后通过二值化处理的方式,将显著性物体分割出来,最后过滤非必要窗口,继而提高检测效率。实验中采用HOG方法提取行人特征,运用线性SVM进行检测,最后验证新方法的有效性。实验中,使用大小为300×451Dpi、261×400Dpi的图像,检测窗口数量分别减少了44.21%、34.96%,检测速率分别提高了9.30%、12.73%。实验结果表明,相比于传统检测方法,新方法提高了检测效率。

Effect of Grain Particle Size on Quality of Multi-grain Chips Under Screw Extrusion Processing

Multi-grain chips processed by screw extrusion processing have high nutrition and production value with a low glycemic index.To analyze the effects of particle sizes on the qualities of multi-grain chips extrusion processing by using a single screw extruder,mesh numbers were selected as 80,100 and 120 to describe different grain particle sizes.It was found that the particle sizes of the raw materials had effects on the basic components,sensory properties,texture properties,antioxidant activities and in vitro digestibilities of extruded chips.The results showed that with the decrease of particle sizes,the moisture contents,starch contents of the chips decreased,and fat contents,dietary fiber contents increased.The edible qualities of the chips increased with the decrease of the grain sizes of raw materials.The antioxidant capacities and estimated glycemic indexes of the three kinds of chips showed a trend of decreasing first,and then increasing with the decrease of particle sizes.Correlation analysis showed that the total antioxidant capacities of chips were negatively correlated with the estimated glycemic indexes.The research results provided valuable guidance for the quality processing of multi-grain chips under extrusion processing.

Analysis of Process of Microwave Puffing Blueberry Snacks

In order to reveal the mechanism of microwave puffing berry snack, a center combination experiment method was employed to explore the puffing process of blueberry snacks. Blueberry as the raw material, the microwave power, initial moisture content, puffing time and mass were employed as experimental factors. The pressure, temperature, amount of water vapor and puffing properties in terms of the volume, hardness and brittleness were employed as target parameters. The higher microwave intensity and initial moisture content resulted in the more amount of water vapor in the snacks and more holes in the appropriate puffing time. The shape and structure of the snacks tended to be stable with the removal of moisture.

Drying Characteristics of Microwave-assisted Foam Drying of Corn Soaking Water

To improve the industrial utilization of corn soaking water, the yeast protein powder was produced by microwave-assisted foam drying. Firstly, preparation experiments were carded out, which included the foaming characteristic experiments of fermentation broth and that about the effects of carbon and nitrogen ratio on solid content in the fermentation broth. Secondly, the drying characteristics experiment of corn soaking water was studied, which selected the microwave power, material amount and thickness as the influencing factors for the single experiment. The results showed that the final moisture content （d.b.） and drying rate were significantly affected by those factors.

Effect of Drying Methods on Moisture Distribution of Paddy Rice

Variation during IR and heated-air drying process and effect on milling quality with moisture differenoe of paddy floe were investigated. The results indicate that the moisture SD （Standard Deviation） decreases during IR （Infrared RadiationS） and heated-alr （HA） drying process, and moisture uniform level for the paddy rice dried by IR treatment is higher than that by heated-air treatment. No matter IR or HA, the higher initial SD of MCs is, the bigger of the variable of the SDR value will be at the beginning stage of dried paddy storage.

高校劳动教育融入新工科人才培养的路径探析

以东北农业大学为样本进行调研,发现劳动教育融入新工科人才培养存在“教育教学受到重视,但整体设计和远期规划不够到位”“培养内容基本明确,但教育教学资源不够丰富”“教学方式趋于成熟,但对实战实践平台建设不够重视”“教育工作初见成效,但人才培养效果评价不够系统”等问题。为充分发挥劳动教育实践育人优势、有效提升新工科人才培养质量,高校要加强思政引领,系统培养劳动能力;严选教学内容,提升学生学习兴趣;发挥学校优势,整合教师资源;加强实训力度,融合创新人才培养方法;完善考核方式,完善人才培养评价体系。