<![CDATA[Current Chinese Engineering Science (Volume 2 - Issue 1)]]> https://benthamscience.com/journal/187 RSS Feed for Journals | BenthamScience EurekaSelect (+https://benthamscience.com) 2022-11-28 <![CDATA[Current Chinese Engineering Science (Volume 2 - Issue 1)]]> https://benthamscience.com/journal/187 <![CDATA[Meet the Associate Editor-in-Chief]]>https://benthamscience.com/article/1278802022-11-28 <![CDATA[Current Research Developments of Electromagnetic Joining Technology in China-A Review]]>https://benthamscience.com/article/1159072022-11-28 <![CDATA[Disinfection of Electrical Hand Dryer Using Plasma and Ozone]]>https://benthamscience.com/article/1205362022-11-28 <![CDATA[Challenges, Trends and Solutions for Communication Networks and Cyber-Security in Smart Grid]]>https://benthamscience.com/article/1201842022-11-28 <![CDATA[Study on the Fire Resistance of Concrete-filled Steel Tubular Column to Composite Beam Joints after Earthquake Damage]]>https://benthamscience.com/article/1177272022-11-28Background: Post-earthquake fire is one of the secondary disasters caused by the earthquake; many earthquakes around the world have brought about severe fires and led to enormous losses. It is of great significance to study the fire resistance of structures after earthquake to improve the level of urban disaster prevention and reduce the fire loss.

Methods: A nonlinear finite element model of composite joints subjected to post-earthquake fires is established based on ABAQUS software. The state after the earthquake damage is imported into the thermal-stress analysis model through the restart request in ABAQUS, and considered as the initial state of the thermal-stress analysis model.

Results: It is noticed that when the damage index is less than 0.517, the damage level shows significant effect on the fire resistance, but the influence is no longer significant when the damage index reaches 0.781. When only the column is exposed to fire, the column showed obvious local buckling and overall bending deformation. Meanwhile, when the joint area below the concrete slab is exposed to fire, the joint shows a mixed failure mode of the excessive vertical displacement of beam end and column instability.

Conclusion: The fire resistance of the composite joint decreases gradually with the increase of seismic damage level. The fire condition has a significant effect on the fire resistance of the composite joints; with the increase of fire area, the fire resistance of composite joints with same damage degrees decreases gradually.

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<![CDATA[Output Power Modeling of Wind Turbine Based on State Curve Analysis]]>https://benthamscience.com/article/1192412022-11-28Background: In wind power generation, the power curve can reflect the overall power generation performance of a wind turbine. How to make the power curve have high precision and be easy to interpret is a hot research topic.

Objective: Because the current power curve modeling method is not comprehensive in feature selection, the simplified model and state curve of a wind turbine are introduced to avoid feature selection and make the model interpret easily.

Methods: A power modeling method based on different working conditions is proposed. The wind turbine system is simplified into three physical models of blades, mechanical transmission and generator, and the energy transfer is expressed by mathematical expressions. The operation process of the wind turbine is divided into three phases: Constant Power (CP), Constant Speed (CS), and Maximum Power Point Tracking (MPPT), and the power expression of each phase is given after the analysis of state curves.

Results: The effectiveness of the proposed method is verified by the Supervisory Control and Data Acquisition (SCADA) data of a 2MW wind turbine. The experimental results show that the Mean Absolute Percentage Error (MAPE) index of the proposed power modeling method based on state curve analysis is 11.56%, which indicates that the power prediction result of this method is better than that of the sixth-order polynomial regression method, whose MAPE is 13.88%.

Conclusion: The results show that the proposed method is feasible with high transparency and is interpreted easily.

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<![CDATA[Computational Study of Treated and Untreated Corn Husk Powder and Polycaprolactone for Microwave Shielding Using Finite Element Method]]>https://benthamscience.com/article/1231072022-11-28Introduction: Microwave devices and communication devices produce electric fields, which may be dangerous to nearby applications. These fields can be shielded using conductive shells that are closed on all sides. These close conductive shells are often designed using thin metal foils. However, for many applications, these enclosures can add significantly high cost and weight to a product, and a minute gap in the enclosure can completely damage the benefits of the enclosure. Moreso, the metal foil is not flexible to complex geometry. The solution to the gap identified is to use a light, flexible and durable material that can shield unwanted electromagnetic (EM) waves. For this work, treated and untreated corn husk powder (CHP) was produced from agricultural waste residues by grinding into powder form, while polycaprolactone (PCL) was commercially obtained.

Methods: The composites of the materials were synthesized using the melt blending technique. The dielectric property of the produced materials was investigated using the open-ended coaxial probe technique. Moreover, the dielectric constant values were used in the composites' computational study using the finite element method.

Results: Results indicate that the treated dielectric property was greater than the untreated composites. The alkali treatment affected the value of the dielectric constant, shielding effectiveness, and transmission coefficients of the composites. The highest dielectric property obtained was 3.42 for the 30 % filler with a loss factor of 0.47. The filler played a significant role in the values of shielding effectiveness (SE) obtained, where the highest filler was able to shield radiation by up to -4.21 dB at the frequency range measured.

Conclusion: The electric field intensity observed that the highest filler had a minimum transmitted intensity of 2185.87 v/m. The high loss factor of 0.47 obtained for the 30% filler content can produce waveguide terminators and other microwave components from this composite.

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