Design of Experiment Analysis of an Electronics Package Lid Using Finite Element Analysis

A design of experiment analysis is reported on data from warpage simulations using finite element analysis of a lidded electronics package. Warpage in a lid of an optical electronics package can detrimentally affect the reliability of the package as well as its optical performance. The present study focuses on the variety of materials and designs of lids relevant to recent technologies in electronics packaging. The finite element analysis (FEA) formulation in this study accurately predicts deformation and warpage in the elastic region with optimal computational time achieved through a choice of boundary conditions and mesh sensitivity studies. The results from FEA are compared to analytical calculations made using the classical laminate plate theory (CLPT) as well as the modified Suhir’s theory. It is observed that FEA results are more accurate as they account for the performance of die attach/ underfill materials regardless of the small thickness of the layer. The FEA data are finally used to conduct a design of experiments (DOE) analysis to investigate the influence of 3 distinct designs and 6 material choices on warpage of a lid. The analysis indicates that there is no significant interaction between the two parameters expected to affect the warpage in the lid. Material properties of the lid are found to have a greater effect on the warpage of the lid as compared to variabilities introduced in lid designs in this study. The FEA simulations performed consider only material behavior within the elastic limit and, in some situations, plastic deformation may occur which is more permanent and as such requires a more comprehensive analysis in the plastic region to enhance the data set for DOE studies

An Experimental Investigation on Interference of Piled Rafts in Soft Soil

By using small scale model tests, the interference effect on the vertical load-deformation behavior of a number of equally spaced rafts and piled rafts, placed in the artificially consolidated soft clay was investigated. The effect of spacing (s) among foundations on the results was explored. A new experimental setup was proposed in which uniform load was applied by using steel beam of adequate flexural strength and ball bearings to transfer the vertical load equally on both the foundations. The bearing capacity decreases continuously with decrease in spacing among the foundations. The interference effect becomes further prominent with piled raft foundation. In contrast to decrease in the bearing capacity, with decrease in spacing of foundations, an increase in the foundations settlement associated with the ultimate state of shear failure was observed. The present experimental observations were compared to the results obtained by using PLAXIS. The results of this laboratory investigation will be helpful in finding the minimum spacing between the rafts and piled raft foundation for better performance. Keywords: Piled raft; Model test; soft clay; Interference effect; spacing; PLAXI

ASSESSMENT OF CEMENT CONTENT IN CURED CONCRETE BY CHEMICAL STUDY OF MATERIALS SCIENCE AND SUSTAINABLE MANUFACTURING TECHNOLOGY

An effort was made in this investigation to determine the cement content in cured concrete. A test procedure used to determine calcium oxide which further leads to the assessment of cement in concrete that has been hardened was applied to the laboratory test. The content of cement of three different concrete samples that have been hardened of known proportions was precisely determined by applying the simplified California Test 403 procedure. The California Test 403 method originally used in order to determine the calcium oxide concentration in hardened concrete has been simplified by modifying several steps. The test results are verified by parameter determination of the composition in concrete by X-ray diffraction (XRD) using the JCP (Joint Committee of powder diffraction standards file) database. Good agreement between the results obtained by the titration and analytical methods of the instrument and the actual results is observed

The cross-sectional analytical study of COVID and post COVID mucormycosis in diabetic and non-diabetic patients and their outcomes

Background: Mucormycosis, a rare but serious fungal infection, has shown a concerning rise in incidence among COVID and post-COVID patients, with males constituting majority of cases. This study aimed to investigate the impact of diabetes mellitus (DM) on outcomes in patients with COVID and post-COVID mucormycosis. Given the known association between DM and increased susceptibility to infections, particularly fungal ones, understanding the role of DM in exacerbating mucormycosis outcomes is crucial for clinical management. Methods: A cross-sectional analytical study was conducted, involving a cohort of 50 patients with mucormycosis, equally divided into diabetic and non-diabetic groups. Data on morbidity, complications, hospitalization rates, and mortality were collected and compared between the two groups. Additionally, glycemic control status was assessed among diabetic patients to evaluate its impact on outcomes. Results: Among the 50 patients analyzed, diabetic individuals displayed significantly poorer outcomes compared to their non-diabetic counterparts. This included increased morbidity, complications, hospitalization rates, and mortality. Moreover, patients with uncontrolled DM exhibited the worst outcomes, highlighting the critical importance of managing glycemic control during mucormycosis treatment. Conclusions: The study underscores the necessity of vigilant monitoring and targeted interventions, particularly in diabetic individuals, to mitigate the adverse effects of mucormycosis in the context of COVID-19. Effective management of diabetes, especially glycemic control, is crucial for improving overall patient outcomes and reducing the burden of mucormycosis-related complications and mortality in both COVID and post-COVID scenarios. Further research is warranted to refine treatment protocols and optimize outcomes for this vulnerable population

Study Response of Fixed Base and Isolation Base

ABSTRACT:-A natural calamity like an earthquake has taken the tolls of millions of lives through out in past. The nature of induced forces due to earthquake is reckless and last only for short duration of time. The base isolation system separates the structure from its foundation and primarily moves the natural frequency of the structure away from the excitation frequency range through its low stiffness relative to that of the upper structure. Hence base isolation allows a design for smaller seismic forces and higher levels of safety compared with the design of fixed-base structures. Instead, a well-designed isolated building will not suffer any important damages even under strong earthquakes and so no repairing works will be needed. In this study, the response of fixed base and isolated base building is to be studied with different techniques and it is to be studied with the suitable software. In this paper the (G+25) storied frame structure is taken to compared with the seismic effect of fixed bas structure with respect isolated structure .the (G+25) storied RCC frame structure is design is design with base isolation by using ETAB software by the lead rubber bearing (LRB) is used as an isolator which having efficient result for RCC frame structure over the fixed base structure the report show that the values for lateral loads come very less by using lead rubber bearing

Utility of chest ultrasound in the diagnosis of ventilator-associated pneumonia in the critical care unit of a tertiary care center: a prospective observational study

Ventilator-associated pneumonia (VAP) is a type of nosocomial pneumonia developing in patients who are mechanically ventilated for ≥48 hours. Lung ultrasound (LUS) has been shown to be useful in evaluating various pathologic pulmonary conditions. We aimed to study the utility of chest ultrasound in the diagnosis of VAP in a critical care unit. This was a monocentric, prospective observational study carried out in the intensive care unit (ICU) of our institution. On clinical suspicion of VAP, patients were subjected to ultrasound chest (lung) examination, which was done in a supine position in six areas of each hemithorax on the same day, and endotracheal aspirate (ETA) for gram stain and aerobic culture was sent within 6 hours. The final diagnosis of VAP was made when ETA culture was positive (>105 CFU/mL). Days of mechanical ventilation, ICU stay, hospital stay, and mortality were separately recorded for monitoring outcomes. Diagnostic performance of risk factors for VAP was analyzed by parameters like sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio (positive and negative). Concerning LUS signs, subpleural consolidations >2 had a sensitivity of 96% and specificity of 63% with an odds ratio of 51.43 in predicting VAP. Dynamic air bronchogram within consolidation was seen in 45% of patients with a sensitivity and specificity of 29% and 73%, respectively. A clinical LUS score >2 had a sensitivity of 100% in predicting VAP. LUS is a robust diagnostic tool with high sensitivity for diagnosing VAP. Clinical trials are needed to study whether LUS can be used as a tool for early diagnosis of VAP, which will help in the timely introduction of antibiotics

Ammonium Toxicity and Potassium Limitation in Yeast

DNA microarray analysis of gene expression in steady-state chemostat cultures limited for potassium revealed a surprising connection between potassium and ammonium: potassium limits growth only when ammonium is the nitrogen source. Under potassium limitation, ammonium appears to be toxic for Saccharomyces cerevisiae. This ammonium toxicity, which appears to occur by leakage of ammonium through potassium channels, is recapitulated under high-potassium conditions by over-expression of ammonium transporters. Although ammonium toxicity is well established in metazoans, it has never been reported for yeast. To characterize the response to ammonium toxicity, we examined the filtrates of these cultures for compounds whose excretion might serve to detoxify the ammonium (such as urea in mammals). Using liquid chromatography–tandem mass spectrometry to assay for a wide array of metabolites, we detected excreted amino acids. The amounts of amino acids excreted increased in relation to the severity of growth impairment by ammonium, suggesting that amino acid excretion is used by yeast for ammonium detoxification