Pressure Cycle Induced Fatigue Failure of Wrinkled Energy Pipelines

The development of a small wrinkle in a buried pipeline can be a challenging issue for pipeline operators to approach. Although a vast majority of research has been conducted, to evaluate the integrity of a pipeline showing signs of irregularities such as corrosion, pipe wall buckling and/or rippling; there is limited research data or guideline(s) available as to how to assess the severity of a small wrinkle defect. If not dealt with appropriately, these small wrinkle defects can lead to further damage of the pipe wall as a result of fatigue damage caused by internal pressure cycling. This research program was designed to investigate the behaviour and structural integrity of wrinkled pipelines subjected to severe pressure cyclic loading. This research program comprises of both lab-based experimental work, followed by a finite element analysis (FEA) based numerical approach. This study shows that a pipe with a wrinkle defect may lead to fatigue failure resulting in circumferential cracking at the wrinkle apex, due to localized stress concentration. Additionally, it was also found that the magnitude of the stress concentration is highly dependent on the geometry of the wrinkle profile. Analysis based on experimental and numerical results was undertaken to evaluate stress concentration factors, which could be used to establish the remaining fatigue life of a wrinkled pipe subjected to typical pressure fluctuations arising in oil and gas pipelines

The Information Content of Directors’ Trades: Empirical Analysis of the Australian Market

We examine the trading activities of directors in shares of their own companies on the Australian Stock Exchange during the July-December 2005 period. We find that directors of small companies in particular earn abnormal return after both their ‘Purchase’ and as well as their ‘Sale’ trade. Directors of these companies have an uncanny ability to time the market by trading when mispricing is greatest, and are able to predict the future performance of their firms in short run. For directors of medium and large companies, we find evidence that ‘Sale’ trades are the ones which work as loss avoiders. Outsiders recognise to some extent that directors’ trades are informative, however they are slow to incorporate the new information into prices, refuting much of the market efficiency literature.

A Framework for Strategic Cloud Migration

This paper presents a novel framework for organisations to carry out a structured feasibility study on Cloud migration and to decide Cloud Migration Strategy. Following the framework helps an organisation to decide whether Cloud migration is a feasible option for them, and if so, the best strategic approach towards Cloud migration. It is a crucial and sensitive part for any organisation to decide whether they should move to Cloud Computing platform. The decision requires strategic approach with proper feasibility study. Several technological, human, security and financial factors are involved in decision making process to move to the Cloud. The proposed framework helps an organisation to carry out a feasibility study to decide whether to move to the Cloud, and if so, what would be the best approach towards Cloud migration. The proposed framework addresses the factors that an organisation must explore to decide on Cloud migration. Cloud Computing has its own pros and cons. A whimsical decision to move to the Cloud may be disastrous for an organisation. Following the proposed framework will help organisations to carry out a structured and integrated feasibility study deal with the decision on Cloud migration

High Isolation Single-Pole Four-Throw RF MEMS Switch Based on Series-Shunt Configuration

This paper presents a novel design of single-pole four-throw (SP4T) RF-MEMS switch employing both capacitive and ohmic switches. It is designed on high-resistivity silicon substrate and has a compact area of 1.06 mm2. The series or ohmic switches have been designed to provide low insertion loss with good ohmic contact. The pull-in voltage for ohmic switches is calculated to be 7.19 V. Shunt or capacitive switches have been used in each port to improve the isolation for higher frequencies. The proposed SP4T switch provides excellent RF performances with isolation better than 70.64 dB and insertion loss less than 0.72 dB for X-band between the input port and each output port

Prediction of Corporate Bankruptcy using Financial Ratios and News

A corporate’s insolvency can have catastrophic effects on not only the corporate but also on the returns of its lenders and investors. Predicting bankruptcy has been one of the most sought-after areas for researchers for many decades. This study involves predicting the bankruptcy of the United States corporates using financial ratios and news data. The financial ratios of the companies were extracted from yearly financial reports of the companies, and the news data of the companies was scrapped from online newspapers, reports and articles using Google News. The news data was analyzed for negative and positive sentiments. The sentiment scores, along with the financial ratios of the companies, were given as features to the machine learning models. Various models were analyzed for their results such as Random Forest, Logistic Regression and Support Vector Machines (SVM). The study finds the best results from the random forest model with an accuracy of 90%. Moreover, the significant feature importance of the sentiment score given by the model proves that unstructured data, such as news, can play a crucial part in predicting bankruptcy in conjunction with the structured data, such as financial ratios

Performance and Economic Analysis of Multi-Rotor Wind Turbine

Power production of a wind turbine is dependent upon its rotor size and at present wind turbines with large rotor diameter (>175 m) are available in the market. However major problems associated with such large size conventional turbines are their cost & noise pollution. Due to these reason researchers have diverted their attention towards lower sized equivalent multi-rotor wind turbines. These turbines are found to be cheaper and good performers. Keeping it in view, in this paper an effort has been made to compare the energy yield and economics of two types of wind turbines i.e. single rotor & multi rotor wind turbine. Power, energy and cost models as proposed are used to determine the annual energy yield and economics of multi-rotor turbines. Simulation results as presented in this paper justify the suitability of multi-rotor wind turbine in place of single rotor configuration. Such turbines deliver more energy yield with low installation cost in contrast to single rotor turbines

May-Thurner syndrome : an uncommon and incidental finding in a postpartum female

May-Thurner syndrome or Cockett syndrome is a pathological condition that arises due to extrinsic compression on iliocaval venous territory, leading to venous outflow obstruction. Here, author presents an incidental finding of left common iliac vein extrinsic compression by right common iliac artery with collateral vessels in the pelvis in a postpartum female