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Edge computing has gained widespread usage in intelligent applications due to its benefits, including low latency, high bandwidth, and cost-effectiveness.However, it also faces many security challenges due to its distributed, real-time, multi-source and heterogeneous data characteristics.Identity authentication serves as the initial step for terminal to access to the network and acts as the first line of defense for edge computing.To address the security issues in the edge computing environment, a terminal cross-domain authentication protocol suitable for the edge computing environment was proposed based on the ＆quot;cloud-edge-end＆quot; three-level network authentication architecture.Access authentication was implemented between terminals and local edge nodes based on the SM9 algorithm, and session keys were negotiated.The secret key was combined with symmetric encryption technology and hash function to achieve cross-domain authentication for the terminal.The pseudonym mechanism was used in the authentication process to protect the privacy of end users.The terminal only needs to register once, and it can roam randomly between different security domains.BAN logic was used to prove the correctness of the protocol and analyze its security.The results show that this protocol is capable of resisting common attacks in IoT scenarios, and it features characteristics such as single sign-on and user anonymity.The performance of the cross-domain authentication protocol was evaluated based on computational and communication costs, and compared with existing schemes.The experimental results show that this protocol outperforms other schemes in terms of computational and communication costs, making it suitable for resource-constrained terminal devices.Overall, the proposed protocol offers lightweight and secure identity authentication within edge computing environments.

Conducting supply-demand prediction and structural adjustment of planting and breeding industries based on changes in food consumption is crucial for ensuring food security of China. This study analyzes the characteristics of food consumption structure and the development trends of planting and breeding industries in China and estimates the demand and supply data of staple grains, feed grains, and forage crops closely related to the planting and breeding industries. The analysis results of supplydemand balance are obtained. Targeted adjustment directions are proposed, including expanding the planting of protein feed crops, oil-bearing crops, and high-quality forage crops; stabilizing the production of livestock and poultry; vigorously developing grassbased animal husbandry; promoting an all-encompassing approach to food; and exploring multiple sources of food. The study also elaborates on the implementation paths: optimizing planting structure by adjusting regional layout, developing circular agriculture that integrates crop farming and animal husbandry, constructing a diversified food supply system, and comprehensively enhancing innovation capabilities regarding agricultural technologies. To better ensure national food security, we proposes to improve the policy and technological support systems, allocate agricultural resources toward roduction areas, establish a regional collaboration mechanism, and adjust policies and statistical standards for staple grain, feed grain, and forage crop production.

【Objective】 Climate change will increase the frequency of extreme weathers such as drought and flooding. The aim of this paper is to analyze the seasonal droughts occurring from 1961 to 2016 in the six main basins across Yunnan province. 【Method】 The analysis was based on monthly precipitation measured from 124 meteorological stations across the province from 1961 to 2016. The basin rainfall was calculated using the corrected Thiessen polygon method, and the CSPI (corrected SPI) method was used to calculate the drought index by dividing droughts into moderate drought, severe drought and special droughts. Seasonal drought intensity, occurring time of the droughts at the meteorological stations in different basins were used to analyze the spatiotemporal variation in the drought across the province. 【Result】 There are 6 spring drought type meteorological stations, 69 winter drought type meteorological stations and 49 strong winter drought type meteorological stations across the province. The drought in all basins occurred mainly in winter and spring. Spatially, Jinsha basin saw the severest droughts in in winter and spring, followed by Honghe and Lancang basins. Temporally, there have been a decrease in winter and spring droughts in all six basins over the 65 years. 【Conclusion】 The corrected Thiessen polygon method and CSPI method are adequate to calculate spatiotemporal variation in droughts at basin scale. There were local seasonal droughts occurring in the middle reaches of Jinsha basin (Kunming and Chuxiong) and the middle reaches of Honghe basin and the lower reaches of Lancang basin (Jinghong and Pu’er).

LiV3O8 with nanorod structure was prepared by hydrothermal-solid method. In this work, the structure and morphology of LiV3O8 were characterized by XRD, FTIR, SEM, XPS, etc., and the electrochemically switched ion exchange (ESIX) performance of LiV3O8 synthesized at different calcination temperatures was investigated. The experiment results show that LiV3O8 calcined at 500 ℃ had evenly nanorod morphological structure and the best electrochemical performance. The lithium ion adsorption capacity of LiV3O8 film reached 36.36 mg/g at 100 mg/L Li+ solution by ESIX technology. Moreover, LiV3O8 exhibited high selectivity and stability towards Li+. The selectivity factors of Li+/K+ and Li+/Mg2+ reached 38.43 and 4.75, respectively, when the initial molar ratios of Li+/K+/Mg2+ is 1∶1∶1. The lithium ion adsorption capacity of LiV3O8 film still maintained 98.3% of the initial value after 5 cycles.

As the second-largest economy in the world, China has extremely rich coal resources, but the coal resources available for direct mining and utilization are relatively limited and need to rely heavily on imports. To ensure the quality and safety of imported coal, it is urgent to establish a set of effective origin traceability methods to trace the origin and identify the adulteration of imported coal. In this study, coal samples from five importing countries were analysed by gas chromatography-mass spectrometry (GC-MS), and representative biological fingerprint compounds in the organic matter were analysed qualitatively and quantitatively to provide enlightenment for new methods and technologies of coal origin traceability. According to the relationship between Ph/nC18 and Pr/nC17, the coal samples of these five countries are considered to be in the low maturity stage. The coal of Australia, Russia, Malaysia and the Philippines is mainly type Ⅲ organic matter in a terrestrial oxidation environment. Except for the C56 sample from Indonesia, the distribution of n-alkanes in other coal samples from Indonesia and all coal samples from the Philippines mainly have medium and high molecular weight, suggesting that the source of parent material may be terrestrial higher plants. Different samples from different sedimentary environments have different types of organic matter input, and the application of specific indicators of organic matters is an effective method for geographical origin traceability of imported coal to a certain extent.

The Maogaitu Sn ore spot in Hexigten Banner, Inner Mongolia is a newly discovered ore spot in the south section of Greater Khingan Range by Beijing Institute of Geology for Mineral Resources. It is tectonically located in the polymetallic metallogenic belt in the south centralsection of Greater Khingan Range, and the mineralization is characterized by cassiterite-quartz veins. Ore minerals of the ores are dominated by cassiterite with trace amounts of sphalerite, galena, chalcopyrite and silver minerals, while gangue minerals are mainly quartz and fluorite. As discovered recently without detailed studies, the genesis and age of the Maogaitu Sn ore spot are not clearly addressed. A number of tin polymetallic deposits are documented to develop in the polymetallic metallogenic belt in the south central section of Greater Khingan Range. The ages of these tin polymetallic deposits are constrained to be mostly around the Early Cretaceous, and to be genetically related to the Early Cretaceous granite. In order to address the relationship of the Maogaitu Sn ore spot with regional metallogeny, we obtained the age of the Maogaitu Sn ore spot by using LA-ICPMS U-Pb isotopic dating of cassiterite from a quartz vein-type tin ore sample. The results show that the sample yields a 207Pb/206Pb-238U/206Pb concordant age of (130.2±3.4) Ma (MSWD=2.9), similar to the timing of the major tin mineralization event in the region. The new findings imply that the middle and south sections of Greater Khingan Range could be good targets for Sn polymetallic exploration.

[Purpose/Significance] Based on the investigation of scientific data literacy ability of domestic graduate students, this paper constructs the scientific data literacy ability training system of university libraries, so as to provide targeted suggestions for university libraries to carry out scientific data literacy education. [Method/Process] Based on the data literacy evaluation research, a questionnaire was designed, and graduate students s of Jiangnan University were taken as the sample. [Results/Conclusions] The research shows that the data consciousness and data ethics of postgraduates in domestic universities are showing an optimistic trend. But students' ability of data collection, data organization and management, data utilization and preservation need to be improved, especially the data analysis capabilities need to be urgently strengthened. Based on this, this paper constructs a training system in accordance with the current situation of scientific data literacy of university graduates from four aspects of training objectives, contents, methods and evaluation.

ObjectiveTo explore the effect of flipped classroom mode in the clinical probation teaching for undergraduate mental health students， so as to expand the new mode of clinical teaching in psychiatry department.MethodsA total of 85 undergraduate psychiatric students from Xinxiang Medical University in 2016 were selected. All participants were divided into experimental group （n=43） and control group （n=42） according to the random number table method. The flipped classroom clinical teaching mode was adopted to experimental group， and the traditional practice mode for control group. The probation lasted for 12 weeks. Theoretical knowledge of symptomology， psychiatric clinical skills （OSCE）， doctor-patient communication ability（SEGUE） and clinical thinking ability were assessed at the end of probation.ResultsAfter the probation， students in experimental group obtained higher scores in theoretical knowledge， clinical skills， doctor-patient communication ability and clinical thinking ability compared with control group. The differences were statistically significant ［（33.08±1.72） vs. （32.06±2.33）， （51.61±2.12） vs. （48.32±2.86）， （18.14±1.98） vs. （14.62±2.15）， （91.26±14.13） vs. （82.40±10.89）， t=2.307， 6.034， 3.230， 7.846， P

Objective To provide the basis scientific evidence for the timely response of this kind of poisoning incident by field epidemiological investigation and the identification of poisonous mushroom of two poisoning incidents in Shaowu, Fujian Province. Methods Case data, field epidemiological investigation data and suspected poisonous mushroom samples were collected for morphological and internal transcribed spacer molecular biological identification, and the event was analyzed and managed. Results On September 1 and 2, 2018, two mushroom poisoning incidents occurred in Dafugang town and Xiaojiafang town, Shaowu City, 3 villagers ate wild mushrooms and suffered from nausea, vomiting, dizziness, excessive sweating, abdominal pain, diarrhea and other symptoms within 0.5 to 1.5 hours after meals. They were sent to the hospital for treatment and diagnosed as mushroom poisoning. Gastroenteritis and choline poisoning were the main poisoning manifestations. After admission, patients were given symptomatic support treatment and discharged from the hospital at 3-4 d. The sample of poisonous mushroom was identified as Entoloma omiense by morphology and molecular biology. Conclusion Two poisoning incidents were caused by eating Entoloma omiense by mistake. The research on this kind of mushroom should be strengthened to prevent the occurrence of this kind of poisoning.

Objective The epidemiological characteristics and patterns of foodborne disease events in Nanping City were analyzed to provide a basis for formulating prevention and control strategies of foodborne disease. Methods Foodborne disease incidents reported from all over Nanping City during 1998 and 2017 were collected, and a retrospective descriptive analysis was conducted. Results A total of 184 foodborne disease incidents were reported in Nanping, with 2 871 cases and 40 deaths, with an annual average incidence of 5.12/100 000 and a case fatality rate of 1.39%. The peak season for foodborne illness was the third quarter, with the highest number of incidents and deaths in August. The number of incidents and patients with the largest number were pathogenic microbial events, accounting for 43.48% (80/184) and 64.86% (1 862/2 871) respectively. Toxic plant accounted for 35.87% (66/184) and 10.80% (310/2 871). The most common pathogenic factor was the accidental eating of poisonous mushrooms, accounting for 29.89% (55/184). Vibrio parahaemolyticus was the second factor, accounting for 12.50% (23/184). The most fatal cases were from mushroom, accounting for 87.50% (35/40). Family were the most occurred site, accounted for 39.13% (72/184), and 66.67% (48/72) were caused by toxic plants. Hotels and restaurants accounted for 22.28% (41/184) and 80.49% (33/41) were pathogenic microorganisms. Conclusion The control strategy of foodborne disease events in Nanping should focus on reducing wild mushroom poisoning and changing bad eating habits, carrying out a wide range of food safety education in vulnerable seasons, months and regions, establishing an effective early warning, monitoring and government supervision mechanism, and reducing the occurrence of foodborne disease.

The paper analyzes the advantages and disadvantages of two different energy management strategies which are the management strategy based on the dynamic system running state and the management strategy based on the driving cycle. The paper focuses on the study of the strategy based on the driving cycle, and points out that though the operation process of the global optimization strategy based on the driving cycle takes long and large amount of calculation so that it can hardly be used in the real vehicle. The strategy can be taken as the reference for the ideal optimization control target. In order to achieve the real-time optimal control, there are mainly the method based on the driving cycle of recognition control strategy and the method based on model predictive control, etc. It makes the exploration to predict the real-time optimal control strategy based on the driving cycle become real, and the effects of the control results get close to the offline global optimization. The proposed strategy is a new research hotspot and research trend of energy management strategy.

[Objective] This study aimed to elucidate the tissue-specific expression profiles of the Pd-PapMYC2 gene in the 'Shanxin' hybrid poplar (Populus davidiana X P. alba var. pyramidlis, cv' Shanxin') under biotic stress, abiotic stress and hormone induction. [Method] The PdPapMYC2 gene was cloned and its coded protein was analyzed by bioinformatic tools. Quantitative reverse transcription poly-merase chain reaction (qRT-PCR) assays were performed to analyze the expression profiles of PdPapMYC2 in different compartments (referred to as tissues hereafter) of poplar including shoot tip, different compartments of stem, leaves and roots. The changes of the tissue-specific expression levels of PdPap-MYC2 were also studied under three abiotic treatments of salt stress (NaCl), alkali stress (Na2CO3) and high osmotic stress (PEG6000), five biotic stress treatments of Sclerotinia sclerotiorum, Rhizoctonia sola-ni, Fusarium oxysporum, Alternaria alternata and Cytospora chrysosperma infection, and induction of three phytohormones including abscisic acid (ABA), jasmonic acid (JA) and salicylic acid (SA). [Result] The PdPapMYC2 gene was 1 944 bp in length and encoded a 647-amino-acid protein containing a conserved bHLH-MYC_N superfamily domain and a conserved bHLH_SF superfamily domain. The subcellu-lar localization of the PdPapMYC2 protein was predicted to be in the nucleus. The secondary structures mainly consisted of crhelices and random coils. Tertiary structure analysis suggested the highest structural consistency between PdPapMYC2 and 4rru. 1 of Arabidopsis. Phylogenetic analysis showed that PtMYC2 in P. tomentosa was the most closely related to PdPapMYC2. The qRT-PCR assays showed that PdPap-MYC2 was constitutively expressed in shoot tips, stems, leaves and roots. Under NaCl, Na2CO3 and PEG6000 stress, the relative expression of PdPapMYC2 in shoot tip was significantly down-regulated (P<0.05). In mature leaves, PdPapMYC2 expression was significantly up-regulated under NaCl stress (P<0.05) and down-regulated under alkali and high osmotic stresses. In roots, PdPapMYC2 expression was down-regulated under all three abiotic treatments without significant differences. After 48 hours of infection by five soil-borne pathogenic fungi, PdPapMYC2 expression was down-regulated in shoot tips and it was slightly up-regulated when induced by Alternaria alternata. In roots, PdPapMYC2 expression was up-regulated under the induction of Fusarium oxysporum, Cytospora chrysosperma, Alternaria alternata and Sclerotinia sclerotiorum. PdPapMYC2 expression was significantly up-regulated under JA induction (P<0.05) and down-regulated under ABA or SA induction in all tissues. [Conclusion] PdPapMYC2 gene expressed in multiple tissues and involved in regulating resistance of plants to various stresses and responding to stress-related hormones. [ABSTRACT FROM AUTHOR]

In order to solve the current problems about environmental pollution of agricultural waste and explore the technology of producing organic fertilizer by composting with pig manure and edible fungi residue, an experiment was conducted to study dynamic changes of several parameters including heat, pH value, organic carbon (C), germination index (GI), nutrient nitrogen (N), phosphorus (P) and potassium (K) during the natural fermentation. The experiment was based on the four ratios of 9:1, 8:2, 7:3 and 6:4 of pig manure and edible fungi residue in high-temperature composting experiment. The results showed as followed. The temperatures of all disposals were over 50 degrees centigrade at about the 3rd day. It maintained a high temperature for from 25 to 32 d, and then began to decrease. Duration of the high-temperature composting was longer while the ratio of the mushroom residue got more. From the experiment, we could see that the high-temperature duration of the disposal with the ratio of 6:4 was 7 d longer than the disposal with the ratio of 9:1. The pH values of all disposals, ranging from 6.83 to 8.62, increased rapidly and then decreased smoothly in the 22 d. Total N of the nutrient decreased with the loss of ammonia in the early, and then the relative quality of the total N began to rise while the total mass was reducing along with the loss of C content. At the end of the composting, the total N contents of the disposals A and B decreased by 2.9 and 1.0 g/kg, respectively, but the disposals C and D increased by 1.6 and 1.9 g/kg, respectively. The total P and total K contents have been on a slow upward trend, until the end of the composting they increased by 14.2%-36.4% and 28.1%-34.7% respectively. The organic C content decreased in general. At the end of the composting, the organic C contents of all disposals respectively decreased by 16.3%, 14.5%, 13.6% and 11.9%. Due to the rich source of N in the early time, microbes multiplied and let out large-scale ammonia N, which resulted in the rapid increase in the C/N ratio, and then the average ratio declined; and the 4 disposals decreased by 0.67, 2.08, 4.48 and 4.49 respectively in the end. Except the disposal with the ratio of 6:4, the GI of all disposals respectively reached 80% on the 23rd, 33rd, 47th day. At the same time, the toxicity of the piles extract liquid increased on plants due to the accretion of the ratio of fungi residue. The total nutrient contents of N, P and K were in a flat or a small decline and then continued to rise in the early period (in about 19 d), which were respectively 5.93%, 5.57%, 5.64% and 5.13% for all disposals at the end of the composting. In addition, the disposal with the ratio of 6:4 was less than 5% in the most period of the composting (within 45 d), but the rest disposals were more than 5% after about 21-25 d. Considering the factors of the compost quality and production cycle comprehensively, the appropriate ratio of manure to mushroom residue is 8:2 for making scale production of organic fertilizer. Furthermore, on account of the low C/N ratio of manure and mushroom residue, it is better to add some annexing agent with high C/N ratio such as rice bran for improving the efficiency of composting. [ABSTRACT FROM AUTHOR]

In view of the requirements of the special structural features of a series-parallel hybrid electric bus on its control strategy, an optimization simulation on its energy management strategy, which determines the power distribution between engine and battery, is conducted by using Pontryagin's minimum principle and based on the solution flow chart designed and the simulation model built, with battery power as control variable and minimizing fuel consumption as objective. The results demonstrate the marked effects of optimization on energy management strategy based on Pontryagin's minimum principle with the fuel consumption per 100km 18. 33% lower than that with rule-based control strategy. [ABSTRACT FROM AUTHOR]

Aiming at the effects of many factors such as uncertain driving environment and different driver's styles on the fuel economy of novel series-parallel hybrid electric bus (SPHEB) in real world driving conditions, a Markov model for driver's required power is built based on statistical data of several city driving cycles, and an energy management strategy based on stochastic dynamic programming (SDP) algorithm is proposed and the control rules for power distribution between engine and battery are obtained. Both the results of simulation on the forward model for novel SPHEB and hardware-in-the-loop test demonstrate that the proposed strategy enables the battery SOC to keep balance within its preset range and makes the engine operate in high efficiency region. In addition the fuel consumption per 100km of novel SPHEB reduces by 30.17% and 11. 29% respectively compared with original bus and that with rule-based strategy. [ABSTRACT FROM AUTHOR]

A three-dimensional heat dissipation model is built for the lithium-ion battery pack in an electric vehicle. Both simulation and test are conducted on the temperature field of lithium-ion battery pack in a condition of cruise driving and natural air cooling with a result showing their consistency in temperature variation trend, meaning the rationality of the model built. On this basis an optimization scheme for the heat dissipation structure of lithium-ion battery pack is proposed and a simulation is performed. The results indicate that after optimization, lithium-ion battery pack has a good cooling effects: the highest temperature of battery pack lowers from 46°C to 33°C and the temperature difference among the batteries is less than 6°C. [ABSTRACT FROM AUTHOR]