Research on the Individuation of Client-Centered Ecommerce

Many enterprises all over the world plunge into developing ecommerce in recent two or three years, but don’t attain their expectant goals. Taking Chinese enterprises as the example, through analyzing the individuating trend of consumption and the operating status of ecommerce, this paper emphasizes that only the enterprises develop client-centered ecommerce considering their practice conditions can they fit the individuating trend of consumption and ecommerce, and puts forward some proposals for the individuation of this client-centered ecommerce for enterprises in new century

Engineered Diffraction Gratings for Acoustic Cloaking

We show that engineered diffraction gratings can considerably simplify the design of acoustic ground cloaking devices. Acoustic reflecting gratings are designed in such a way that all the incident energy is channeled toward the diffracted mode traveling in the direction opposite the direction of the incident field (retroreflection effect), and this effect is used to cloak an object placed over an acoustically rigid surface. Axisymmetric gratings consisting of rigid surfaces with just one groove per unit cell are used to design thin acoustic carpet cloaks. Finally, full-wave numerical simulations are performed and a conical carpet cloak is experimentally tested, showing an excellent scattering-cancellation effect

Reliability analysis of aged natural gas pipelines based on utility theory

Pipelines are of major importance for transport of natural gas, but a lot of the current in-service pipelines are in wear-out phase. Safe and reliable operations of these pipelines are related to economic development and social stability. It is of great importance and practical significance to study when the corroded pipelines will be retired and how to guarantee that these pipelines will be operating under safe and reliable conditions. The paper proposes a model for assessing risk in natural gas pipelines, and for classifying sections of pipeline into risk categories with utility theory. It aims to help transmission and distribution companies when engaged in risk integrated assessment and decision making consider multiple dimensions of risk from pipeline leakage accidents. Firstly, we analyze the corrosion leakage probability of pipeline remaining life using the exponential distribution; secondly, we evaluate the economic loss, loss of life and damage to the environment in terms of the utility function to get the corresponding risk value of external loss. Finally, we calculate the internal economic loss when in-service pipelines are replaced ahead of scheduled time and then schedule a most optimal date to exchange the aging pipelines containing corrosion. To verify the effectiveness of the proposed methods, a numerical application based on a real case study is presented