MISFIRE DETECTION IN A MULTI-CYLINDER DIESEL ENGINE: A MACHINE LEARNING APPROACH

Misfire is another type of abnormal combustion. When engine misfires, cylinder (or cylinders) is not producing its normal amount of power. Engine misfire also has negative effects on engine exhaust emissions such as HC, CO, and NOx. Engine misfire should be detected and eliminated. Normal combustion and misfire in the cylinder (if any) generates vibrations in the engine block. The vibration characters due to misfire are unique for a particular cylinder. This can be diagnosed by processing the vibration signals acquired from the engine cylinder block using a piezoelectric accelerometer. The obtained signals were decoded using statistical parameters, like, Kurtosis, standard deviation, mean, median, etc. Misfire identification algorithms such as AdaBoost, LogitBoost, MultiClass Classifier, and J48 were used as tools for feature selection and classification. The signals were trained and tested by the selected classifiers. The classification accuracy of selected classifiers were compared and presented in this paper. MultiClass Classifier was found to be performing better with selected statistical features compared to other classifiers

Review on free cooling of buildings using phase change materials

The concept of Green building is gaining importance in the present energy scenario and related environmental issues. Free cooling or ventilation cooling is truly a green concept since even 1 g of carbon is not burnt for the purpose of cooling. Also it ensures that a good indoor air quality is maintained in the building. In this paper a detailed review of work carried out by various researchers on free cooling or ventilation cooling is presented. In addition the major challenges and facts posed in the use of phase change material for free cooling system design such as thermal resistance of air and phase change materials, geometry of encapsulation are discussed in detail. Also the method of energy efficient charging and discharging, effect of phase change temperature, insulation and geographical location are also discussed in this paper. This paper also provides lists the PCM candidates used for free cooling.Free cooling Green building PCM LHTES Natural ventilation

Indoors ventilation in times of confinement by SARS-CoV-2 epidemic: A comparative approach between Spain and Italy

With the arrival of the SARS-CoV-2 coronavirus, the scientific academia, as well as policymakers, are striving to conceive solutions as an attempt to contain the spreading of contagion. Among the adopted measures, severe lockdown restrictions were issued to avoid the diffusion of the virus in an uncontrolled way through public spaces. It can be deduced from recent literature that the primary route of transmission is via aerosols, produced mainly in poorly ventilated interior areas where infected people spend a lot of time with other people. Concerning contagion rates, accumulated incidence or number of hospitalizations due to COVID-19, Spain, and Italy have reached very high levels. In this framework, a regression analysis to assess the feasibility of the indoor ventilation measures established in Spain and Italy, with respect to the European framework, is here presented. To this aim, ten cases of housing typology were and analyzed. The results show that the measures established in the applicable regulations to prevent and control the risk of contagion by aerosols are not adequate to guarantee a healthy environment indoors. The current Italian guidelines are more restrictive than in Spain, yet the ventilation levels are still insufficient in times of pandemic