Model reduction for discrete-time switched linear time-delayed systems with finite-frequency specifications

The paper focusses on the model reduction of discrete-time switched linear systems with finite-frequency specifications. First, we propose a performance index that can estimate systematic performance over finite frequency. And then, we use GKYP (generalized Kalman–Yakubovich–Popov lemma) and introduce some relaxation matrices with variable parameters to analyse the problem in different situations. Based on the above conditions, sufficient conditions can be obtained for meeting the index of finite frequency. Finally, we illustrate two numerical examples. The results show that the proposed method can improve approximation performance.

Basalt Fibers in Modified Whisker Reinforced Cementitious Composites

The calcium carbonate whisker (CW) and basalt fiber are gaining popularity due to its enhanced mechanical properties in composites. Also, the short and long fibers provide bridging role and resistance against cracking from micro- to macro-scale, respectively. The usage of long and short hybrid basalt fiber along with addition of CW in cement-based composites is still a research gap. In this work, experimental behavior of CW basalt hybrid fiber reinforced mortar is considered with various content and length (3 mm, 6 mm, 12 mm, and 20 mm) of hybrid basalt fibers. In addition to this, synergy performance index is determined to quantitatively evaluate the positive interaction of hybrid basalt fiber in cementitious materials. The strengthening effect of whiskers and basalt fibers are also studied using scanning electron microscopy. The CW with various basalt fiber contents having different length of hybrid basalt fiber is used. It was found that the four various length of hybrid basalt fiber together with CW in cement mortar exhibited enhanced compressive, flexural, and split tensile strength than that of pure mortar and single length basalt fiber reinforced cementitious mortar. The results of synergy performance index showed similar trend with the experimental results. The strengthening effect caused by step by step crack arresting mechanism was also observed in cementitious material.

Exploratory study explicating value addition of emerging technologies in the infrastructure component of Logistics Performance Index (LPI)

India had undertaken several logistics development agendas.Initiatives were aligned to improve the logistics infrastructure in India. Advancement in technology had also benefited the logistics sector. Logistics Performance Index (LPI) has been a multi-dimensional evaluation criterion developed by the World Bank to assess logistics capabilities of countries. The LPI score of India had been low. Regarding this, present research study aimed to analyse the poor performance of India in LPI and how the deployment of emerging technologies could help improve it. The findings were based on a questionnaire shared with five experts. Delphi technique was applied for this study. The prioritization was identified through Analytical Hierarchy Process. The key findings in this study were prioritization of application of emerging technologies for various sub-dimensions of infrastructure like roadways, railways, ports, airports, warehouse, and institution. Emerging technologies like cloud computing, blockchain, internet of things were emphasized by experts to improve the infrastructure of India.