Multivariable Nonlinear Model Predictive Control for a Petroleum Refinery: Multivariable Nonlinear Model Predictive Control for a Petroleum Refinery

This paper presents a detailed procedure to develop a mathematical modelling and simulation of a distillation column for a real feedstock from a condensate processing plant as an initial step of a project feasibility study. The mathematical model of overall dynamics is established on the dynamic continuity equations of the mass and the energy for each unit operation where the mass and the energy can accumulate. The paper provides a case study tutorial for a typical petroleum refinery engineering design. The dynamic analysis and controller for the distillation systems are extremely complicated due to their nonlinearity and multivariable. A nonlinear model predictive control (NMPC) computational scheme for with soften constraints is developed to verify the applicable ability of a direct NMPC controller for a distillation column dealing with the disturbance and the model-plant mismatch as the influence of the plant feed disturbances

A new routing protocol for ad hoc wireless networks design, implementation and performance evaluation

A collection of mobile nodes can form a multi-hop radio network with a dynamic topology and without the need for any infrastructure such as base stations or wired network. Such a Mobile Ad Hoc Networks (MANETs) maintain their structure and connectivity in a decentralised and distributed fashion. Each mobile node acts as both a router for other nodes traffic, as well as a source of traffic of its own In this thesis we develop and present a new hybrid routing protocol called Multipath Distance Vector Zone Routing Protocol, which is referred to as MDVZRP. In MDVZRP we assume that all the routes in the routing table are active and usable at any time, unless the node received or discovered a broken link. There is no need to periodically update the routing tables, therefore reducing the periodic update messages and hence reducing the control traffic in the entire network. The protocol guarantees loop freedom and alternative disjoint paths. Routes are immediately available within each routing zone. For destinations outside the zone, MDVZRP employs a route discovery technique known as routing information on demand. Once the node is informed by either the MAC layer or itself that it should discover the non- reachable nodes, MDVZRP adopts a new technique. First, we discuss the Ad Hoc networks and routing in general, then the motivation of MDVZRP regarding the nodes‟ flat view, and the selection and acquisition of multipath getting and selection. Furthermore, we describe the stages of MDVZRP and the protocol routing process with examples. The performance of MDVZRP is then evaluated to determine its operating parameters, and also to investigate its performance in a range of different scenarios. Finally, MDVZRP is compared with DSDV and AODV ordinary routing protocols (standard) delivering CBR traffic. Simulation results show that MDVZRP gives a better performance than DSDV in all circumstances, it is also better than AODV in most of the scenarios, especially at low mobility

STUDI EKSPERIMENTAL PENGARUH PENGGUNAAN SEMEN PCC DAN OPC TIPE I TERHADAP KUAT TEKAN BETON

STUDI  EKSPERIMENTAL  PENGARUH  PENGGUNAAN SEMEN PCC DAN OPC TIPE I TERHADAP  KUAT TEKAN  BETO

The Relationship Between Cohesion and the Students' Written English Quality

This study aimed to find out the relationship between cohesion and the quality of the students' written English at the third level of Sudanese secondary schools. The study subjects were two hundred (200) students from Rufa’a city secondary schools. The study assumed some factors that underlie ignorance of cohesion such as L1 interference, overgeneralization, misuse of communicative learning strategies, inadequacy of practical English classes, students' negative attitudes towards English writing and insufficiency of qualified teachers. a test was the elicitation technique to obtain data in this respect. The analytical method was adopted to analyse the test to demonstrate the problem. However, results and findings revealed that students ignore cohesive devices and sentence boundaries. This ignorance is due to MT and overgeneralization sources, teachers' misuse of learning and communication strategies, inadequacy of practical English writing classes, students developed negative attitudes towards English writing, then neither teachers nor students are enthusiastic about writing courses. Accordingly, recommendations are submitted to develop writing standard, beside a prerequisite to qualify teachers for better linguistic performance in order to achieve coherent effective writing Keywords: cohesion, EFL students, writing, attitude

Firms’ Specific Characteristics and Stock Market Returns (Evidence from Listed Food and beverages Firms in Nigeria)

Because of the mix of opinion in the literature, the mix of empirical findings, and the limited empirical works on the relationship between firms’ specific characteristics and Stock Market Returns particularly with reference to listed food and beverages firms in Nigeria, it is not out of place to conduct further research on this area to ascertain position. Hence, the study investigated the impact of certain firms’ attributes namely: Market Capitalization, Debt-to-Equity Financing and Earnings per Share on Stock Market Returns of listed food and beverages firms in Nigeria for the period 2007-2013. The population comprises all the twenty-one (21) food and beverages firms listed on the Nigerian Stock Exchange (NSE) December, 2013. Out of which nine (9) firms constitute the sample of the study. The study adopted both correlation and ex-post facto research design. The data for the study was purely from secondary sources obtained from the annual reports of the sampled firms as well as NSE fact book. Data was analyzed using several options of multiple panel data regression. But the most robust of all is OLS regression as suggested by ‘Breusch and Pagan Lagrangian Multiplier Test for Random Effect’. The findings revealed that Market Capitalization has a significant negative impact on Stock Market Returns of listed food and beverages firms in Nigeria; while the impact of Debt-to-Equity Financing and Earnings per Share on Stock Market Returns are found to be positive and statistically significant. Based on these findings the study recommend as follows: that government and policy maker (Security and Exchange Commission) should design and implement more stringent rule where firms will be compelled and monitored on providing high quality financial reporting, so as to be reporting earnings that reflect their actual performance. This would prevent investors from falling on to the trap of earnings manipulation (as it happened to shareholders of Cadbury Nigeria plc.). In addition, prospective investors should not only focus on huge returns for investing in smaller capitalized or high levered firms; rather, further analysis need to be carried out to tradeoff between risk and returns. Keywords: market capitalization, debt-to-equity financing, earnings per share, stock market returns and stock marke

PEMANAATAN ABU TERBANG BATU BARA SEBAGAI PENGGANTI SEBAGIAN SEMEN UNTUK CAMPURAN BETON

PEMANAATAN ABU TERBANG BATU BARA SEBAGAI PENGGANTI SEBAGIAN SEMENUNTUK CAMPURAN BETO

Choice of specialization among female clinical medical students of Bayero University Kano, Nigeria

Background: The field of medicine is very wide; female medical students also have their choice of specialization which many develop in medical schools due to different factors.Methodology: It was a cross sectional study that was conducted among female clinical medical students of Bayero University Kano. Ethical approval was obtained from the hospital Ethical Committee. Questionnaire was administered to all consenting female students. Data were analysed by SPSS Electronic Software Version 18 (SPSS Inc, IL, Chicago, USA). A P value of less than 0.05 was considered statistically significant.Results: Eighty five female medical students participated in the study. Mean (SD) age was 23.09 ± 1.8 years. Seventy two (84.70%) chose clinical medicine to be their future career while 13 (15.30%) were undecided. Only 15 (22.70%) decided to specialize in their career of choice. Obstetrics and Gynaecology was the most interested speciality of choice (30.80%). Most students were interested in the reward in working in the speciality 54 (68.40%) followed by interest in the clinical work 52 (65.80%). Many of the respondents 41 (49.4%) considered their career development as a priority in future career plans in practice location, and educational environment for children 40 (51.90%). Only 15 (18.00%) were keenly motivated to work in rural areas regardless of the duration of time.Conclusion: Female medical students preferred to be clinicians in their future career with obstetrics and gynaecology as the most interested speciality of choice. Their career development and educational environment for children were the priority in future career plans in practice location.Keywords: Choice of specialization; Female medical students; Kano; Nigeri

Landholders’ Awareness of Compulsory Acquisition of Land and Compensation Process in Bauchi, Nigeria

This study aims to assess landholder’s awareness of compulsory acquisition of land on their satisfaction with the compensation process in Bauchi, Nigeria, to identify areas of weakness in the process and propose areas of improvement. The study adopted the use of a quantitative approach and data were collected through a questionnaire survey from 327 landholders affected by the compulsory acquisition and compensation exercise by the Bauchi State Government. The data collected were subjected to descriptive with mean ranking, frequency distribution. The study revealed that the respondents are aware of the process before the compulsory acquisition and during the process of compulsory acquisition they were also aware of. This means that the respondents agreed that they were aware of the process/procedures involved in compulsory land acquisition, laws, and procedures guiding compulsory land acquisition and compensation process. It recommended that Landholders should be made more aware of the process involved in compulsory acquisition and compensation not only at inception but up to the end of the exercise

Public Infrastructure Provision in Bauchi Metropolis, Nigeria

This study aims to assess the Public infrastructure provision in Bauchi Metropolis, Nigeria, to propose areas of improvement. The study adopted the use of a quantitative approach and data were collected through a questionnaire survey from 382 house head holds proportionate selected from the target population in Bauchi metropolis. The data collected were subjected to descriptive with mean ranking, frequency distribution. The study revealed that communication facilities were the most provided facility provision, followed by market facilities and water facilities provision. Solid waste disposal facilities and fire protection services were the least facilities provided in the study area. It recommended that public infrastructural facilities provided in the area should be based on the resident’s preference and need