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Traditional power grids have been the major source of electricity for several households and industries for a number of years. However, with that kind of supply, every member of the grid is affected whenever there is a fault on the transmission line connecting them. With that in mind, microgrids, usually powered by numerous distributed electrical sources, were introduced to curb this problem, and as such, energy users have also become producers themselves. Nonetheless, the generation of power by distributed sources brings about unpredictability on the network and, in essence, problems in energy sharing. Peer-to-peer (P2P) energy trading has several advantages and has been introduced to mitigate energy sharing problems. With networked energy trading comes the issue of trust, as several prosumers are concerned about their privacy and security in such environments. Therefore, this work leverages the advantages of blockchain in proposing a secure energy trading platform for all parties involved. Coupled with certificateless signcryption, an immutable energy trading market is designed, and its use case is applicable in smart cities. A thorough security analysis was performed, and the efficiency of our proposed solution is backed by numerical results.

As an accurate 2D/3D fabrication tool, inkjet printing technology has great potential in preparation of micro electronic devices. The morphology of droplets produced by the inkjet printer has a great impact on the accuracy of deposition. In this study, the drop-on-demand (DoD) inkjet simulation model was established, and the accuracy of the simulation model was verified by corresponding experiments. The simulation result shows that the velocity of the droplet front and tail, as well as the time to disconnect from the nozzle is mainly affected by density (ρ), viscosity (μ) and surface tension (σ) of droplets. When the liquid filament is about to disconnect from the nozzle, the filament length and filament front velocity are found to have a linear correlation with σ/ρμand ln(ρ/(μσ12)).

Cadmium (Cd) is one of the main pollutants in the water environment, exhibiting bioaccumulation and toxicological effects on fish. In this study, dongtingking crucian carp (Carassius auratus indigentiaus) were exposed to 0 (control group), 0.1, 0.5 and 1.0 mg/L Cd for 30 days. The results showed that the liver body index and spleen body index increased gradually with increases in the Cd concentration, and morphological changes were observed in the spleen and liver. The level of accumulation of Cd in the tissues was as follows: gut > middle kidney > liver > spleen > gills > heart > brain > muscles. With increases in the concentration, the Cd enrichment concentration increased gradually in the spleen and middle kidney. Pathological features were observed in the intestines, gills, spleen and liver of C. auratus indigentiausafter 1.0 mg/L Cd exposure. The Lys content and the AKP, ACP, CAT, GSH-PX and SOD activities were significantly increased in the low concentration Cd exposure group (0.1 mg/L), and dramatically decreased in the high concentration Cd exposure group (1.0 mg/L). The expression levels of the IL-6 and IL-1β genes in the intestines, gills, spleen and liver, TNF-ɑ gene expression in the gills, spleen and liver, IgM, IgZ and C3 genes expression in the liver decreased gradually with increases in the Cd concentration, while the expression of TNF-ɑ gene in intestine, IgM, IgZ and C3 genes expression in intestine and gill increased with increasing Cd concentration. The expression of IgM, IgZ and C3 genes in the spleen were significantly increased in the 0.1 mg/L Cd exposure group, but significantly decreased in the 0.5 mg/L and 1.0 mg/L Cd exposure groups. These results indicate that low concentration of Cd (0.1 mg/L) might induce toxic excitability, but higher concentration of Cd (1.0 mg/L) inhibit the antioxidant and immune systems.

As an increasingly mature additive manufacturing technology for metal materials, Selective Laser Melting (SLM) technology has become a hot topic in many application fields. However, due to the fast-moving velocity and small scale of the laser beam in the SLM process, it is very difficult to directly observe the microstructural changes in the SLM additive manufacturing process. In this study, a macro-micro coupled simulation model of Inconel 718 SLM process was established to study the solidification behavior of the molten pool. The macro temperature field is obtained by the finite difference method based on the birth and death grid algorithm. The local temperature intercepted from the macro temperature field is employed as the input condition for phase field microstructure calculation. Dendrite morphology, intercellular spacing, and microsegregation are simulated under the coupled model. The result shows that the solidification structure of IN718 alloy in the micro molten pool formed by SLM grows in the form of a non-flat interface. The primary dendrite spacing predicted by the simulation is in good agreement with Hunt model at the initial stage of solidification. The solute trapping caused by non-equilibrium solidification makes dendrites dissolve more Nb, resulting in microsegregation.

Recent investigations on pomegranate products have significantly increased and successfully drawn consumers’ attention to nutritional and medicinal values, promoting the pomegranate industry's development worldwide. However, little information on pomegranates grown in China is available. Morphological and chemical characterizations of fruits and arils from 20 pomegranate cultivars in six regions of China were investigated. Combined with overall scores by principal component analysis, ‘Yushiliu No. 1’, ‘Taishanhong No. 2’, ‘Tunisia’ and ‘Mollar’ were promising cultivars, and Chinese researchers bred the first two. It was surprising that ‘Mollar’ had bigger fruit size and more aril moisture grown in China than in Spain. Cultivars with higher anthocyanin content in arils were ‘Turkey’, ‘Moyu’ and ‘Red Angel’, which might be used as the source of natural red food colourants. While red husk ‘Hongruyi’ and ‘Hongshuangxi’ with higher vitamin C, aril moisture and lower titratable acid in arils, might also be promising cultivars for further various utilization. Furthermore, the comparison of ‘Tunisia’ fruits from four regions revealed that cultivation locations had more influence on fruit traits than genotypes. Maturity index classification was established for Chinese pomegranate cultivars. Therefore, the results would provide a valuable guide for agricultural cultivation, industrial utilization, and breeding.

Cloud servers offer data owners the opportunityto upload and store encrypted data that several data users can access. However, after outsourcing data to the cloud, data owners have limited control of their data, and external systems are incorporated to manage it. Several research-based solutions use encryption techniques to prevent unauthorized access to the data but ignore the challenge of maintaining the trace of valid changes applied to the data. Provenance data can be used to ascertain the integrity of data and, therefore, should be immutable and secured from adversaries since it contains private information. This article proposes an efficient way of securing access logs by leveraging blockchain. A generic framework is designed, tested, and evaluated, with results showing our model can effectively enhance the security of provenance data. This work considers two categories of data users and account for the distinct roles and permitted actions on the outsourced data. In summary, this work ensures that the data is trustworthy, and verification and management of the outsourced data are assured. Experimental results illustrate the efficiency and scalability of our solution.

The evolution of the Internet of Things has seen data sharing as one of its most useful applications in cloud computing. As eye-catching as this technology has been, data security remains one of the obstacles it faces since the wrongful use of data leads to several damages. In this article, we propose a proxy re-encryption approach to secure data sharing in cloud environments. Data owners can outsource their encrypted data to the cloud using identity-based encryption, while proxy re-encryption construction will grant legitimate users access to the data. With the Internet of Things devices being resource-constrained, an edge device acts as a proxy server to handle intensive computations. Also, we make use of the features of information-centric networking to deliver cached content in the proxy effectively, thus improving the quality of service and making good use of the network bandwidth. Further, our system model is based on blockchain, a disruptive technology that enables decentralization in data sharing. It mitigates the bottlenecks in centralized systems and achieves fine-grained access control to data. The security analysis and evaluation of our scheme show the promise of our approach in ensuring data confidentiality, integrity, and security.

The productivity evaluation of gas reservoirs is used to determine the optimal number of well pattern, which is an important part of the preparation of gas reservoir development plan. Using integral transformation and asymptotic analyses to solve the pseudo steady-state flow model in closed rectangular gas reservoir of constant thickness, analytic solution of pressure distribution of eccentric well can be obtained. This paper presents mathematical model of multiple wells producing from a closed gas reservoir by applying the principle of pressure superposition. The pseudo steady-state dimensionless production index is introduced to solve the multiple well mathematical models under the constant pressure, and the number of production wells and cumulative production in different production interval are obtained. The results of the calculation shows that the curve of the cumulative production and economic benefits have a maximum value when the producing time, gas price, and drilling costs are given, so it can determine the optimal number of wells and provide the basis for making gas reservoir development plan.

Career indecision is a difficult obstacle confronting adolescents. Traditional vocational assessment research measures it by means of questionnaires and diagnoses the potential sources of career indecision. Based on the diagnostic outcomes, career counselors develop treatment plans tailored to students. However, because of personal motives and the architecture of the mind, it may be difficult for students to know themselves, and the outcome of questionnaires may not fully reflect their inner states and statuses. Self-perception theory suggests that students’ behavior could be used as a clue for inference. Thus, we proposed a data-driven framework for forecasting student career choice upon graduation based on their behavior in and around the campus, thereby playing an important role in supporting career counseling and career guidance. By evaluating on 10M behavior data of over four thousand students, we show the potential of this framework for this functionality.

For long femoropopliteal occlusive lesions, the immediate technical failure (ITF) of endovascular treatment (EVT) is relatively high. Therefore, this study aims to reveal risk factors and establish a prediction model of ITF of EVT in femoropopliteal occlusive disease (FPOD) patients based on preoperative clinical date that may be helpful to the clinical procedures.

ABSTRACTThe taste of umami peptide H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA) is controversial. One possible reason for this controversy is the use of chemically synthesized LGAGGSLA to confirm its taste. To explore other ways to further confirm the flavor of LGAGGSLA, we developed a new strategy to prepare a bio-source peptide by adopting a gene engineering method to express LGAGGSLA in recombinant Escherichia coli. In our previous work, we structured the LGAGGSLA recombinant expression system and optimized the culturing conditions for preparing a fusion protein. However, the fusion protein was not cleaved by enterokinase to obtain LGAGGSLA. Because the cleavage conditions of commercial enterokinase were not specific and recombinant engineered bacteria had the potential to be used in industrial processes, in this addendum, we calculated the mass and volume yields of key processing steps in the preparation of LGAGGSLA, and established a model of cleavage conditions with the cleavage ratio of LGAGGSLA. When the LGAGGSLA was confirmed to show umami taste, it is considered as a new umami or umami enhancer. The gene information of LGAGGSLA should have a great potential in the development of new flavor product and food product containing high umami flavor.

AbstractThis study investigated the mechanism and influencing factors of herding effect in network public opinion of college students. Experiments by controlling sources of ideas and the strength of concern explore how college students process information of public opinion on the network. To explore factors that influence college students generating herding effect in the public opinion on the network, questionnaires and data test were used. The result shows that herding effect is the result of consensus heuristic and competence heuristic. On the other hand, various sources of information, which are from either the majority or experts, have equal impact on college students’ herding effect in network public opinion. Besides, college students’ knowledge structure is not significant to generate herding effect. On the contrary, gender, geography and original opinions have a significant impact on the generation of herding

AbstractIn this research, a novel dual-model system, one-dimensional stratiform cold cloud model (1DSC) coupled to Weather Research and Forecast (WRF) model (WRF-IDSC for short), was employed to investigate the effects of cloud seeding by silver iodide (Agl) on rain enhancement. Driven by changing environmental conditions extracted from the WRF model, WRF-IDSC could be used to assess the cloud seeding effects quantitatively. The employment of WRF-IDSC, in place of a one-dimensional two-moment cloud seeding model applied to a three-dimensional mesoscale cloud-resolving model, was found to result in massive reduction of computational resources. Numerical experiments with WRF-IDSC were conducted for a real stratiform precipitation event observed on 4–5 July 2004, in Northeast China. A good agreement between the observed and modeled cloud system ensured the ability of WRF-IDSC to simulate the observed precipitation process efficiently. Sensitivity tests were performed with different seeding times, locations, and amounts. Experimental results showed that the optimum seeding effect (defined as the percentage of rain enhancement or rain enhancement rate) could be achieved through proper seeding at locations of maximum cloud water content when the updraft was strong. The optimum seeding effect was found to increase by 5.61% when the cloud was seeded at 5.5 km above ground level around 2300 UTC 4 July 2004, with the maximum Agl mixing ratio (Xs) equaling 15 ng kg-1. On the other hand, for an overseeded cloud, a significant reduction occurred in the accumulated precipitation (12.42%) as Xsreached 100 ng kg-1. This study demonstrates the potential of WRFIDSC in determining the optimal Agl seeding strategy in practical operations of precipitation enhancement.

AbstractThe ice water content (IWC) distribution in a mixed-phase cloud system was investigated using CloudSat data, aircraft measurements, and the Weather Research and Forecasting (WRF) model. Simulated precipitation and IWC were in general agreement with rain gauge, satellite, and aircraft observations. The cloud case was characterized by a predominant cold layer and high IWC throughout the cloud-development and precipitation stages. The CloudSat-retrieved products suggested that the IWC was distributed from 4.0 to 8.0 km, with the maximum values (up to 0.5 g m-3) at 5.0-6.0 km at the earlymature stage of cloud development. High IWC (up to 0.8 g m-3) was also detected by airborne probes at 4.2 and 3.6 km at the late-mature stage. The WRF model simulation revealed that the predominant riming facilitated rapid accumulation of high IWC at 3.0-6.0 km.

C24H22N9NdO17, triclinic, P1̅ (no. 2), a= 7.6445(15) Å, b= 7.9378(16) Å, c= 25.741(5) Å, α= 94.51(3)°, β= 91.76(3)°, γ= 97.34(3)°, V= 1543.1(5) Å3, Z= 2, Rgt(F)= 0.0274, wRref(F2)= 0.0686, T= 290(2) K.

This paper presents a general analytical model of flexible isolation system for application to the installation of high-speed machines and lightweight structures. Piezoelectric stack actuators are employed in the model to achieve vibration control of flexible structures, and dynamic characteristics are also investigated. Mobility technique is used to derive the governing equations of the system. The power flow transmitted into the foundation is solved and considered as a cost function to achieve optimal control of vibration isolation. Some numerical simulations revealed that the analytical model is effective as piezoelectric stack actuators can achieve substantial vibration attenuation by selecting proper value of the input voltage.

This paper presents a general analytical model of flexible isolation system for application to the installation of high-speed machines and lightweight structures. Piezoelectric stack actuators are employed in the model to achieve vibration control of flexible structures, and dynamic characteristics are also investigated. Mobility technique is used to derive the governing equations of the system. The power flow transmitted into the foundation is solved and considered as a cost function to achieve optimal control of vibration isolation. Some numerical simulations revealed that the analytical model is effective as piezoelectric stack actuators can achieve substantial vibration attenuation by selecting proper value of the input voltage.

In this paper the effects of Fe–Fe bond length change on magnetic properties and magnetic entropy change have been investigated on LaFe_12.4−xSi_xCo_0.6 and LaFe_12.3−xAl_xCo_0.7 intermetallic compounds. According to the analyses of Fe–Fe bond length change, the variation of Curie temperature and the unusual magnetic phase transition which results in the large magnetic entropy change were explained. The effects of the substitution of Co and Si for Fe on magnetic entropy change and field-induced itinerant-electron metamagnetic transition in LaFe_12.4−xSi_xCo_0.6 compounds were also studied and the considerable magnetic entropy change has been achieved.

To observe the clinical efficacy of combined acupuncture and Tuina in the treatment of enuresis following occult cleft spine and seek quantified indexes for result assessment, 40 subjects were treated by above methods and B-ultrasonically examined before and after treatment to determine the capacity of bladder and the residual urine inside it. The total effective rate was 90%; there was a difference of the capacity of bladder between before and after treatment (P<0.05); 11 cases suffered from residual urine, and there was also significant difference of residual urine between before and after treatment (P<0.01). It is revealed that this method can increase the capacity of bladder and diminish residual urine.