Forecasting Gas Compressibility Factor Using Artificial Neural Network Tool for Niger-Delta Gas Reservoir

Accurate prediction of gas compressibility factor is important in engineering applications such as gas metering, pipeline design, reserves estimation, gas flow rate, and material balance calculations. This factor also is important in calculating gas properties such as gas formation volume factor, gas isothermal compressibility, viscosity and density. Compressibility factor value shows how much the real gas deviates from the ideal gas at a given pressure and temperature. Most often, compressibility factor values can be determined experimentally from collected laboratory samples but frequently this measurement is not always available. In such cases, the natural gas property can be determined using empirical correlations or iteratively using equation of state (EOS). Therefore, the aim of this work is to develop ANN model to accurately predict the gas compressibility factor; as well to compare its performance with existing empirical gas compressibility factor correlations. The new model was developed using 513 PVT data points obtained from Niger-Delta region of Nigeria. The data used wasrandomly divided into three parts, of which 60% was used for training, 20% for validation, and 20% for testing. Both quantitative and qualitative assessments were employed to evaluate the accuracy of the new model to the existing empirical correlations. The ANN model performed better than the existing empirical correlations by the statistical parameters used having the lowest rank of 1.37 and better performance plot

Efficient Online Timed Pattern Matching by Automata-Based Skipping

The timed pattern matching problem is an actively studied topic because of its relevance in monitoring of real-time systems. There one is given a log $w$ and a specification $\mathcal{A}$ (given by a timed word and a timed automaton in this paper), and one wishes to return the set of intervals for which the log $w$, when restricted to the interval, satisfies the specification $\mathcal{A}$. In our previous work we presented an efficient timed pattern matching algorithm: it adopts a skipping mechanism inspired by the classic Boyer--Moore (BM) string matching algorithm. In this work we tackle the problem of online timed pattern matching, towards embedded applications where it is vital to process a vast amount of incoming data in a timely manner. Specifically, we start with the Franek-Jennings-Smyth (FJS) string matching algorithm---a recent variant of the BM algorithm---and extend it to timed pattern matching. Our experiments indicate the efficiency of our FJS-type algorithm in online and offline timed pattern matching

The rise of policy coherence for development: a multi-causal approach

In recent years policy coherence for development (PCD) has become a key principle in international development debates, and it is likely to become even more relevant in the discussions on the post-2015 sustainable development goals. This article addresses the rise of PCD on the Western donors’ aid agenda. While the concept already appeared in the work of Organisation for Economic Co-operation and Development (OECD) in the early 1990s, it took until 2007 before PCD became one of the Organisation’s key priorities. We adopt a complexity-sensitive perspective, involving a process-tracing analysis and a multi-causal explanatory framework. We argue that the rise of PCD is not as contingent as it looks. While actors such as the EU, the DAC and OECD Secretariat were the ‘active causes’ of the rise of PCD, it is equally important to look at the underlying ‘constitutive causes’ which enabled policy coherence to thrive well

Widespread range expansions shape latitudinal variation in insect thermal limits

I thank the authors of previous studies on global variation in insect thermal tolerances who have generously provided open access use of their data sets.Peer reviewedPostprin

A COMPARATIVE STUDY ON THE PERFORMANCE OF THE DOMESTIC REFRIGERATOR USINGR600A AND LPG WITH VARYING REFRIGERANT CHARGE AND CAPILLARY TUBE LENGTH

A comparative experimental study on the performance of a domestic refrigerator using R600A and LPG with a varying refrigerant charge (wr) and capillary tube length (L) was carried out. The enthalpy of the refrigerants R600A and LPG for each data set for the experimental conditions were obtained by using REFPROP soft ware (version 9.0). The results show that the design temperature and pull-down time set by ISO for a small refrigerator are achieved earlier using refrigerant charge 60 g of LPG with a 1.5 m capillary tube length. The highest COP (4.8) was obtained using 60-g charge of LPG with L of 1.5-m. The average COP obtained using LPG was 1.14% higher than that of R600A. Based on the result of electric power consumption, R600A off ered lowest power consumption. The compressor consumed 20% less power compared to LPG in the system. The system performed best with LPG in terms of COP and cooling capacity, while in terms of power consumption R600A performed best

The University, Prevent and Cultures of Compliance

As Ben Martin argues, recent years have witnessed a decisive move toward centralised, hier- archal, managerialist decision-making structures in UK universities. Likewise, he identifies a central paradox at the heart of these changes. Centralisation, bureaucratisation and the ever greater top-down managerial control of academic life have been paralleled, and legitimated, by the language of decentralisation and freedom. This reflects the ‘fundamental paradox of neoliberalism [where the] use of government intervention to establish and regulate markets’ is masked by the rhetoric of the free hand of the market (Letizia, 2015, p.33; see also Harvey, 2005; Klein, 2007). Likewise, the privatisation of universities, resulting from the wholesale reduction of government funding, is paralleled by an increase of government regulation of what universities do (Docherty, 2015, p.42). Such paradoxes are echoed in the specific focus of this article. As part of the 2015 Counterterrorism and Security Act, passed in April 2015, the current UK government has placed a statutory duty, now enforceable by criminal law, upon a broad range of institu- tional authorities, including departments of social work, hospitals, schools and of course colleges and universities, that in their policies and practices they have ‘due regard to the need to prevent people from being drawn into terrorism’. This is the latest in the tranche of ‘anti-terror’ legislation introduced since 2000 and of the Prevent stream of Contest, the government’s overall counter-terrorism strategy. This paper seeks to explore the likely impact of the ‘Prevent duty’ on the life of the contemporary neoliberal university and the manner in which it enmeshes and deepens further a culture of compliance, restricting inquiry and speech in the name of academic freedom and promoting distrust, inequality and alienation in the name of protection and duty of care. To do so, the paper will therefore examine the two distinct but potentially complimentary threats posed by encroaching cultures of com- pliance within universities evident in and relevant to the Prevent duty. In the first place, I want to argue against the stated purpose of the Prevent policy, that in fact the statutory duty and much of the broader field of government measures of which it forms part, has little or nothing to do with preventing people being ‘drawn into terror- ism’. Rather, they are means to institute a bureaucratised technology of surveillance and compliance directed primarily at a ‘suspect community’ of British Muslims, predicated on a rejection of multiculturalism and the promotion of an integrationist agenda