Power equipment vibration visualization using intelligent sensing method based on event-sensing principle

Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault identification.Event-sensing technology can sense the change in surface light intensity caused by object vibration and provide a visual description of vibration behavior.Based on the analysis of the principle underlying the transformation of vibration behavior into event flow data by an event sensor,this paper proposes an algorithm to reconstruct event flow data into a relationship correlating vibration displacement and time to extract the amplitude-frequency characteristics of the vibration signal.A vibration measurement test platform is constructed,and feasibility and effectiveness tests are performed for the vibration motor and other power equipment.The results show that event-sensing technology can effectively perceive the surface vibration behavior of power and provide a wide dynamic range.Furthermore,the vibration measurement and visualization algorithm for power equipment constructed using this technology offers high measurement accuracy and efficiency.The results of this study provide a new noncontact and visual method for locating vibrations and performing amplitude-frequency analysis on power equipment.

Meso-mechanical model of concrete under a penetration load

The influence of concrete components on projectile penetration is significant.To study the relationship between the equivalent mechanical properties and components of concrete under a penetration load,concrete is simplified as a two-phase composite of coarse aggregate and mortar,and a meso-mechanical model is established,including the equivalent equation of state model,the equivalent confining pressure strength model and the equivalent dynamic tensile strength model,considering shear stress,large deformation and pore compression.Tests of the mechanical properties of mortar,concrete and limestone were conducted;the results show that the equivalent mechanical properties of concrete calculated by the meso-mechanical model are consistent with the test results,and the equivalent mechanical properties of concrete with different volume fractions of coarse aggregate are obtained.Meso-scale and macro-scale numerical simulations of a projectile penetrating into concrete are carried out,the penetration depths obtained by meso-scale and macro-scale numerical simulations are consistent for different volume fractions of coarse aggregate and different velocities of the projectile,which verifies the rationality of the meso-mechanical model.

Expression of human yrdC gene promotes proliferation of gastric carcinoma cells

Objective： The aim of the research was to study the function of human yrdC gene in the gastric carcinoma cells. Methods： Human yrdC gene was isolated from human spleen tissue by RT-PCR. Anti-human yrdC monoclonal antibody was prepared by hybridoma cell technique. Recombinant adenovirus Ad.yrdC carrying yrdC gene was constructed by using the AdEasy adenoviral vector system. Recombinant adenovirus Ad.yrdCshRNA mediated yrdCshRNA was prepared by RNA interference technology. Gastric adenocarcinoma BGC-823 cells of moderate differentiation were transfected and absorbance of the transfected cells was calculated at 490 nm by methyl thiazolyl tetrazolium （MTT） method. Results： A value of the transfected Ad.yrdC group was significantly greater than that of the non-transfected and transfected Ad.Null groups, and A value of Ad.yrdCshRNA group was significantly lower than that of the non-transfected and transfected Ad.Null groups. Conclusion： Expression of yrdC gene has a function of promoting the proliferation of gastric carcinoma cells.

Selectively transform lignin into value-added chemicals

Lignin is one of the most important biomass resources. With the increasing consumption of petroleum resource, lignin transformation is of strategic significance and has attracted widely interest. As lignin is a random construction of aromatic monomers, the degradation products are usually very complex, which limits the scaling application of lignin as feedstock for valuable chemicals. Thus, it is desperately desired to develop highly selective approach to lignin conversion. This review first gives a brief introduction to the structure of lignin, and then summarized the methods for selective transformation of lignin into phenols, aldehydes, carboxylic acids, alkanes and arenes. Finally, the challenges and opportunities of lignin selective transformation are discussed.

Response of spatial structure of cotton root to soil-wetting patterns under mulched drip irrigation

The matching relationship between the spatial structure of cotton cluster root systems and soil-wetting patterns under mulched drip irrigation forms the theoretical basis for the technical design of mulched drip irrigation.A 2-year field experiment was conducted,in which different soil-wetting patterns were produced by setting different emitter discharge rates.The envelopes of cotton cluster root length densities were derived using the topological methodology and used to examine the effects of different soil-wetting patterns on the spatial structure of root systems and water uptake capacity within row spaces.The results showed that the root systems in rows of cotton grown under narrower and deeper soil-wetting patterns exhibited a single-peak distribution,while those under wider and shallower soil-wetting patterns exhibited a two-peak distribution.Furthermore,cotton rows grown near mulch edges experienced lower moisture stress,and wider and shallower soil-wetting patterns contributed to greater root growth rates in the vertical direction and resulted in more even potential water uptake capacities.The findings of this study revealed that wider and shallower soil-wetting patterns were more desirable for mulched drip irrigation of cotton and should be considered in the technical design of drip irrigation systems.

Rearrangeability of 7-stage 16 × 16 shuffle exchange networks

It has long been an outstanding conjecture that any(2^(n)×2^(n))-stage shuffle exchange network(Omega net-work)is rearrangeable for 2n 62n.Many researchers have failed to prove this conjecture,including a recent one established by Hasan.However,nobody has pointed out its fallacy.Therefore,as one of the objectives,this paper shall clarify this fact.Since the case of n 53 has been proven by many researchers[1,2],this paper uses a con-structive approach to prove that when n 54,the 7-stage 16616 shuffle exchange network is also rearrangeable.The paper also presents the model of a balanced tree to avoid internal conflict,the representation of permutations using a connection graph and loop graph,and the con-cepts of symmetry graph and identical transform.Based on graphic composition and bipartition,the permutations 16×16 are divided into five classes,with five assignment algorithms proposed.These algorithms are simpler,clearer and easier to program.The techniques used for n=4 may provide hints for the general case of n>4.